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1
Gilfeather, Maryellyn, and E. Roberts. "Pulmonary MRA and Venous MRV." Seminars in Interventional Radiology 15, no. 02 (June 1998): 205–14. http://dx.doi.org/10.1055/s-2008-1057047.
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Roner, Michael R., and Bradley G. Steele. "Features of the mammalian orthoreovirus 3 Dearing l1 single-stranded RNA that direct packaging and serotype restriction." Journal of General Virology 88, no. 12 (December 1, 2007): 3401–12. http://dx.doi.org/10.1099/vir.0.83209-0.
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A series of recombinant mammalian orthoreoviruses (mammalian orthoreovirus 3 Dearing, MRV-3De) were generated that express an MRV-3De λ3–CAT fusion protein. Individual viruses contain L1CAT double-stranded (ds) RNAs that range in length from a minimum of 1020 bp to 4616 bp. The engineered dsRNAs were generated from in vitro-transcribed single-stranded (ss) RNAs and incorporated into infectious virus particles by using reverse genetics. In addition to defining the sequences required for these ssRNAs to be ‘identified’ as l1 ssRNAs, the individual nucleotides in these regions that ‘mark’ each ssRNA as originating from mammalian orthoreovirus 1 Lang (MRV-1La), mammalian orthoreovirus 2 D5/Jones (MRV-2Jo) or MRV-3De have been identified. A C at position 81 in the MRV-1La 5′ 129 nt sequence was able to be replaced with a U, as normally present in MRV-3De; this toggled the activity of the MRV-1La ssRNA to that of an MRV-3De 5′ l1. RNA secondary-structure predictions for the 5′ 129 nt of both the biologically active MRV-3De l1 ssRNA and the U81-MRV-3De-restored MRV-1La 5′ ssRNA predicted a common structure.
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Harima, Hayato, Michihito Sasaki, Masahiro Kajihara, Gabriel Gonzalez, Edgar Simulundu, Eugene C. Bwalya, Yongjin Qiu, et al. "Characterization of mammalian orthoreoviruses isolated from faeces of pigs in Zambia." Journal of General Virology 101, no. 10 (October 1, 2020): 1027–36. http://dx.doi.org/10.1099/jgv.0.001476.
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Mammalian orthoreovirus (MRV) has been identified in humans, livestock and wild animals; this wide host range allows individual MRV to transmit into multiple species. Although several interspecies transmission and genetic reassortment events of MRVs among humans, livestock and wildlife have been reported, the genetic diversity and geographic distribution of MRVs in Africa are poorly understood. In this study, we report the first isolation and characterization of MRVs circulating in a pig population in Zambia. In our screening, MRV genomes were detected in 19.7 % (29/147) of faecal samples collected from pigs by reverse transcription PCR. Three infectious MRV strains (MRV-85, MRV-96 and MRV-117) were successfully isolated, and their complete genomes were sequenced. Recombination analyses based on the complete genome sequences of the isolated MRVs demonstrated that MRV-96 shared the S3 segment with a different MRV isolated from bats, and that the L1 and M3 segments of MRV-117 originated from bat and human MRVs, respectively. Our results suggest that the isolated MRVs emerged through genetic reassortment events with interspecies transmission. Given the lack of information regarding MRVs in Africa, further surveillance of MRVs circulating among humans, domestic animals and wildlife is required to assess potential risk for humans and animals.
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Shajdakov, E. V., A. B. Sannikov, V. M. Emelyanenko, L. N. Kryukova, A. E. Baranova, and M. A. Rachkov. "MRI- and CT-venography in the diagnosis of hemodynamic disorders in patients suffering from lower extremities chronic venous disorders. Part II. Possibilities of MRI in diagnostics of the deep vein thrombosis." Medical Visualization 25, no. 1 (March 24, 2021): 117–39. http://dx.doi.org/10.24835/1607-0763-901.
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In this literature review, the analysis of the studies of venous blood flow pathology in the inferior Vena cava system using magnetic resonance imaging (MRI) is carried out. Special attention is paid to the attempts made to use this method in the diagnosis of chronic lower limb vein disorders (CVD) through magnetic resonance venography (MRV). Historically and methodically, the gradual introduction of MRV methods in the diagnosis of lower limb vein thrombosis (LEDVT) and venous thromboembolism (VTE) has been shown.Methods of non-contrast MRV based on the effect of blood flow, as in the case of MR-Angiography, are divided into two principal groups: methods based on the amplitude effects of Time-of-Flight (TOF) and methods based on Phase Contrast effects (PC). Techniques for conducting contrast-free MRV are described in detail. Attention is paid to pulse sequences used in the world for visualization of veins in contrast-free MRV in TOF and PC mode (FR-FBI, SPADE, SSFP) and post-processing methods: 2D-TOF MRV FLASH, 2D-TOF MRV CRASS, FIPS, VED, VENS.Contrast-enhanced MRV (CE MRV) is based on the use of “blood pool” contrast agents, which feature the ability to form stable compounds with blood plasma proteins. Worldwidesubstances with magnetic and supermagnetic properties based on gadolinium or iron oxide are used as contrast agents for CE MRV. The result of using these contrast agents is an increase in the quality of visualization due to a better signal to noise ratio (SNR) using 3D image processing (3D CE MRV) using fast sequences: GRE, TFLAS, VESPA, CAT, in conditions of direct and indirect CE MRV.It is noted that in recent years, certain restrictions have been imposed on certain linear contrast agents containing gadolinium in their further use. Therefore, for the purpose of CE MRV, it is efficientl to use only cyclic contrast agents to avoid unnecessary risks.Contrast-free MRV has again received intensive development in recent years, due to the restrictions imposed, one of these methods is direct thrombus imaging (Direct Thrombus Imaging – DTI or Magnetic Resonance Direct Thrombus Imaging - MRDTI) using fast pulse sequences: bSSFP, BBTI, DANTE. The latest research on this LEDVT diagnostic method was published in 2019 and has shown high diagnostic value.For all the most commonly used methods of MRV, specificity and sensitivity are shown.Further MRV in patients with CVD and DVT is a promising diagnostic task in modern phlebology. MRV should be introduced into clinical practice more actively than it is today.
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Qin, Qingsong, Craig Hastings, and Cathy L. Miller. "Mammalian Orthoreovirus Particles Induce and Are Recruited into Stress Granules at Early Times Postinfection." Journal of Virology 83, no. 21 (August 26, 2009): 11090–101. http://dx.doi.org/10.1128/jvi.01239-09.
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ABSTRACT Infection with many mammalian orthoreovirus (MRV) strains results in shutoff of host, but not viral, protein synthesis via protein kinase R (PKR) activation and phosphorylation of translation initiation factor eIF2α. Following inhibition of protein synthesis, cellular mRNAs localize to discrete structures in the cytoplasm called stress granules (SGs), where they are held in a translationally inactive state. We examined MRV-infected cells to characterize SG formation in response to MRV infection. We found that SGs formed at early times following infection (2 to 6 h postinfection) in a manner dependent on phosphorylation of eIF2α. MRV induced SG formation in all four eIF2α kinase knockout cell lines, suggesting that at least two kinases are involved in induction of SGs. Inhibitors of MRV disassembly prevented MRV-induced SG formation, indicating that viral uncoating is a required step for SG formation. Neither inactivation of MRV virions by UV light nor treatment of MRV-infected cells with the translational inhibitor puromycin prevented SG formation, suggesting that viral transcription and translation are not required for SG formation. Viral cores were found to colocalize with SGs; however, cores from UV-inactivated virions did not associate with SGs, suggesting that viral core particles are recruited into SGs in a process that requires the synthesis of viral mRNA. These results demonstrate that MRV particles induce SGs in a step following viral disassembly but preceding viral mRNA transcription and that core particles are themselves recruited to SGs, suggesting that the cellular stress response may play a role in the MRV replication cycle.
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Liu, Chun Mei, Xiao Hua Wang, and Mao Sheng Duan. "Research on MRV Establishing in Future Emissions Trading Scheme in China - Based on Analysis on MRV of Overseas Representative Ets." Advanced Materials Research 524-527 (May 2012): 2641–45. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.2641.
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This paper focused on the monitoring, reporting and verification (MRV) establish in China’s future emissions trading scheme (ETs) through the experience from overseas MRV of emissions trading scheme. First, introduced what is ETs and theory of emissions trading scheme. Then, analyzed the key elements in ETs and the effect of MRV in establishing ETs. Third, using comparison analysis summarized the general requirements from MRV of EU ETS, JVETS and RGGI. Finally, summarized the experiences in the aspects: identification of boundary, emission resource, monitoring methodologies, reporting and verification. And proposed some suggestions for MRV establishing in China’s future ETs.
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Rathnayake, Udara, Matt Folley, S. D. G. S. P. Gunawardane, and Carwyn Frost. "Investigation of the Error of Mean Representative Current Velocity Based on the Method of Bins for Tidal Turbines Using ADP Data." Journal of Marine Science and Engineering 8, no. 6 (May 29, 2020): 390. http://dx.doi.org/10.3390/jmse8060390.
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Representing the velocity at a tidal energy extraction site in a standardized manner is essential for the development of the tidal energy sector. The International Electrotechnical Commission (IEC) have issued a technical specification to determine the mean representative current velocity (MRV) relative to a tidal energy converter (TEC). This method determines the MRV using an acoustic Doppler profiler (ADP). This is used to evaluate the power performance of a TEC and so can have a significant influence on the power performance uncertainties, due to the cubed relationship of the MRV and power. This paper investigates these uncertainties in the MRV by considering four sources of uncertainty in the ADP. These are turbulence intensity, tilt, Doppler noise and beam misalignment of an ADP. A synthetically generated dataset is used to define current velocity and profile using the characteristics of currents and ADP. The generated synthetic dataset is processed to calculate the MRV based on the standard IEC method. An alternative method to calculate the MRV, called the temporal-spatial method (TSM), is proposed and the two methodologies are used to assess the error of the MRV. A sensitivity analysis shows that the errors of the MRV based on the standard IEC method are always higher than the TSM. The biases in the MRV based on the different combinations of the uncertainty are investigated and it is found that the bias for the MRVs based on the TSM method is generally less than that of the IEC method.
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Murray, Kenneth E., and Max L. Nibert. "Guanidine Hydrochloride Inhibits Mammalian Orthoreovirus Growth by Reversibly Blocking the Synthesis of Double-Stranded RNA." Journal of Virology 81, no. 9 (February 14, 2007): 4572–84. http://dx.doi.org/10.1128/jvi.02106-06.
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ABSTRACT Millimolar concentrations of guanidine hydrochloride (GuHCl) are known to inhibit the replication of many plant and animal viruses having positive-sense RNA genomes. For example, GuHCl reversibly interacts with the nucleotide-binding region of poliovirus protein 2CATPase, resulting in a specific inhibition of viral negative-sense RNA synthesis. The use of GuHCl thereby allows for the spatiotemporal separation of poliovirus gene expression and RNA replication and provides a powerful tool to synchronize the initiation of negative-sense RNA synthesis during in vitro replication reactions. In the present study, we examined the effect of GuHCl on mammalian orthoreovirus (MRV), a double-stranded RNA (dsRNA) virus from the family Reoviridae. MRV growth in murine L929 cells was reversibly inhibited by 15 mM GuHCl. Furthermore, 15 mM GuHCl provided specific inhibition of viral dsRNA synthesis while sparing both positive-sense RNA synthesis and viral mRNA translation. By using GuHCl to provide temporal separation of MRV gene expression and genome replication, we obtained evidence that MRV primary transcripts support sufficient protein synthesis to assemble morphologically normal viral factories containing functional replicase complexes. In addition, the coordinated use of GuHCl and cycloheximide allowed us to demonstrate that MRV dsRNA synthesis can occur in the absence of ongoing protein synthesis, although to only a limited extent. Future studies utilizing the reversible inhibition of MRV dsRNA synthesis will focus on elucidating the target of GuHCl, as well as the components of the MRV replicase complexes.
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Pratami, Zita Hadiah, Sudiyono Sudiyono, and Yeti Kartikasari. "Analisis Nilai Velocity Encoding terhadap Informasi Citra Magnetic Resonance Venography pada Penderita Tumor Kepala." Jurnal Imejing Diagnostik (JImeD) 2, no. 2 (July 11, 2016): 154–59. http://dx.doi.org/10.31983/jimed.v2i2.3175.
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Background: Brain Magnetic Resonance Venography (MRV) is a MRI examination of veins without contrast media. Phase Contrast (PC) MRV sequences uses phase shift protons that flow along the magnetic gradient into needed area (Field Of View). PC MRV sequences use bipolar gradient to compensate the proton spin speed by adjusting the amplitude. The study aims to determine the Velocity encoding Value (VENC) to MRV image information on brain tumor patient and to determine the best image information through a technic to visualize the veins in brain tumor patient.Methods: This study was a quantitative study with quasi experimental approach. Data were collected in Radiology Department of Dr. Moewardi Surakarta Hospital on May to June 2016. Data was collected using questionnaire filled by three respondents. Data were analyzed statiscally using Friedman test and Wilcoxon test to determine the difference of value of Velocity Encoding (VENC) between 10 cm/sec, 15 cm/sec, 20 cm/sec, as well the mean rank test used to find out the best image information.Results: The statistical test showed that there were significant differences in image information of MRV, between VENC 10 cm/sec, 15 cm/sec and 20 cm/sec with p value was 0.032 (p˂0,05). The best result of MRV image information was when VENC value of 20 cm/sec used, indicated by the mean rank which was 2.83.Conclusion: There were significant differences of MRV image information between VENC 10 cm/sec, 15 cm/sec and 20 cm/sec. The best result of MRV image information was when VENC value of 20 cm/sec used, to visualize better anatomy of the veins, so that the presence of tumor thrombus in the veins can be ensured.
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Tsitouridis, I., P. Papapostolou, J. Rudolf, K. Natsis, L. Tarazi, F. Goutsaridou, M. Emmanouilidou, S. Chondromatidou, and C. Papastergiou. "Non-Neoplastic Dural Sinus Thrombosis." Rivista di Neuroradiologia 18, no. 5-6 (December 2005): 581–88. http://dx.doi.org/10.1177/197140090501800509.
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Magnetic Resonance Imaging (MRI) study of the brain and Magnetic Resonance Venography (MRV) offer major advantages in evaluating patients suspected of having dural sinus thrombosis. Since 2002, we have examined 49 patients in our department with definite dural sinus thrombosis. MRI and MRV revealed the thrombosis of the dural sinus, and the underlying cause in most patients. There is consensus in the literature that MRI scanning in combination with MRV is the method of choice for evaluating dural sinus thrombosis, and this is also the end result of our study. We also compared the 3D-TOF technique and 2D-PC technique for MRV examination and found that the 3D-TOF technique is clearly the method of choice.
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Stein, Barry. "Clinical Applications of MRV." Journal of Vascular and Interventional Radiology 14, no. 2 (February 2003): P202—P205. http://dx.doi.org/10.1016/s1051-0443(03)70179-1.
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Sugiyanto, Sugiyanto, Ardi Soesilo Wibowo, and I. G. Agung Brihaspaty Bhuana. "Analisis Variasi Nilai Velocity Encoding (VENC) terhadap Informasi Anatomi Citra Magnetic Resonance Venography (MRV) Brain pada Modalitas MRI 3 Tesla." Jurnal Imejing Diagnostik (JImeD) 3, no. 1 (January 9, 2017): 189–93. http://dx.doi.org/10.31983/jimed.v3i1.3183.
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Background: The imaging for vein vessels or Magnetic Resonance Venography (MRV) has own role and advantages on MRI examinations, specifically for evaluating intracranial blood vein circulation. MRV generally uses Phase Contrast (PC) method and PC-MRV imaging, there is an important parameter to be considered, its velocity encoding or VENC. VENC is selected before the examination and has to be adjusted the anticipated blood flow velocity in the examined organs. The right selection of VENC will result in optimum intracranial vessels images and accurate diagnose. The aim of this study is to figure out if there is significant effect of VENC on anatomical information of brain MRV and to find out which VENC the best intracranial veins demonstrates.Methods: This research was a quantitative study with quasi – experimental approach. Data were obtained from five healthy volunteers who were scanned by using a 3 Tesla MRI device in Radiology Department Siloam Lippo Village Hospitals. Each volunteer was scanned with five VENC variations: 10 cm/s, 15 cm/s, 20 cm/s, 25 cm/s, and 30 cm/s. The MRV images were assessed by two radiologist as the respondent. The Data were analyzed by simple linear regression test and Friedman test.Result: The results showed that there was significant effect of VENC on anatomical information of brain MRV, with significant value below 0,001 (p value 0,05). Mean rank on Friedman test showed that the best VENC to demonstrate intracranial veins was 25 cm/s.Conclution: There was a significant effect of VENC on anatomical information of brain MRV with the VENC of 25 cm/s gave the best image of intracranial veins in general.
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Maniatis, Danae, Jérôme Gaugris, Danilo Mollicone, Joel Scriven, Alexis Corblin, Cleto Ndikumagenge, André Aquino, Philippe Crete, and Maria-José Sanz-Sanchez. "Financing and current capacity for REDD+ readiness and monitoring, measurement, reporting and verification in the Congo Basin." Philosophical Transactions of the Royal Society B: Biological Sciences 368, no. 1625 (September 5, 2013): 20120310. http://dx.doi.org/10.1098/rstb.2012.0310.
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This paper provides the first critical analysis of the financing and current capacity for REDD+ readiness in the Congo Basin, with a particular focus on the REDD+ component of national forest monitoring and measurement, reporting and verification (M&MRV). We focus on three areas of analysis: (i) general financing for REDD+ readiness especially M&MRV; (ii) capacity and information for REDD+ implementation and M&MRV; (iii) prospects and challenges for REDD+ and M&MRV readiness in terms of financing and capacity. For the first area of analysis, a REDD+ and M&MRV readiness financing database was created based on the information from the REDD+ voluntary database and Internet searches. For the second area of analysis, a qualitative approach to data collection was adopted (semi-structured interviews with key stakeholders, surveys and observations). All 10 countries were visited between 2010 and 2012. We find that: (i) a significant amount of REDD+ financing flows into the Congo Basin (±US$550 million or almost half of the REDD+ financing for the African continent); (ii) across countries, there is an important disequilibrium in terms of REDD+ and M&MRV readiness financing, political engagement, comprehension and capacity, which also appears to be a key barrier to countries receiving equal resources; (iii) most financing appears to go to smaller scale (subnational) REDD+ projects; (iv) four distinct country groups in terms of REDD+ readiness and M&MRV status are identified; and (v) the Congo Basin has a distinct opportunity to have a specific REDD+ financing window for large-scale and more targeted national REDD+ programmes through a specific fund for the region.
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Jha, Bidya Nath, and Govinda Paudel. "REDD Monitoring, Reporting and Verification Systems in Nepal: Gaps, Issues and Challenges." Journal of Forest and Livelihood 9, no. 1 (September 11, 2013): 21–32. http://dx.doi.org/10.3126/jfl.v9i1.8591.
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Reducing Emission from Deforestation and Forest Degradation (REDD) is an incentive based approach for climate change mitigation that has gained global attention. Following the global discourse and trend, Nepal is preparing herself to participate in the REDD implementation process with the financing from the World Bank's Forest Carbon Partnership Facility (FCPF). Developing a measurement, reporting and verification (MRV) system of monitoring carbon emissions is one of the most important aspects of the REDD mechanism. In this article, we analyse the existing forest resource monitoring system in Nepal with reference to requirements for the REDD MRV design as suggested in the Intergovernmental Panel on Climate Change (IPCC) good practice guide. Our analytical focus revolves around understanding the current policy provisions and institutional infrastructure, as well as identifying existing gaps Similarly, we also analyse the national capacity gaps for designing and adopting the REDD MRV. Finally we have outlined possible issues and challenges for designing and implementing REDD MRV in Nepal. Based on all these aspects, we have suggested a MRV system design that would acknowledge the role of existing institutions and consider the state restructuring.DOI: http://dx.doi.org/10.3126/jfl.v9i1.8591 Journal of Forestry and Livelihood Vol.9(1) 2010 21-32
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Panagakos, George, Thiago de Sousa Pessôa, Nick Dessypris, Michael Bruhn Barfod, and Harilaos N. Psaraftis. "Monitoring the Carbon Footprint of Dry Bulk Shipping in the EU: An Early Assessment of the MRV Regulation." Sustainability 11, no. 18 (September 19, 2019): 5133. http://dx.doi.org/10.3390/su11185133.
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Aiming at reducing CO2 emissions from shipping at the EU level, a system for monitoring, reporting, and verification (MRV) of CO2 emissions of ships was introduced in 2015 with the so-called ‘MRV Regulation’. Its stated objective was to produce accurate information on the CO2 emissions of large ships using EU ports and to incentivize energy efficiency improvements by making this information publicly available. On 1 July 2019, the European Commission published the relevant data for 10,880 ships that called at EU ports within 2018. This milestone marked the completion of the first annual cycle of the regulation’s implementation, enabling an early assessment of its effectiveness. To investigate the value of the published data, information was collected on all voyages performed within 2018 by a fleet of 1041 dry bulk carriers operated by a leading Danish shipping company. The MRV indicators were then recalculated on a global basis. The results indicate that the geographic coverage restrictions of the MRV Regulation introduce a significant bias, thus prohibiting their intended use. Nevertheless, the MRV Regulation has played a role in prompting the IMO to adopt its Data Collection System that monitors ship carbon emissions albeit on a global basis.
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Bussiere, Luke D., and Cathy L. Miller. "Reovirus and the Host Integrated Stress Response: On the Frontlines of the Battle to Survive." Viruses 13, no. 2 (January 28, 2021): 200. http://dx.doi.org/10.3390/v13020200.
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Cells are continually exposed to stressful events, which are overcome by the activation of a number of genetic pathways. The integrated stress response (ISR) is a large component of the overall cellular response to stress, which ultimately functions through the phosphorylation of the alpha subunit of eukaryotic initiation factor-2 (eIF2α) to inhibit the energy-taxing process of translation. This response is instrumental in the inhibition of viral infection and contributes to evolution in viruses. Mammalian orthoreovirus (MRV), an oncolytic virus that has shown promise in over 30 phase I–III clinical trials, has been shown to induce multiple arms within the ISR pathway, but it successfully evades, modulates, or subverts each cellular attempt to inhibit viral translation. MRV has not yet received Food and Drug Administration (FDA) approval for general use in the clinic; therefore, researchers continue to study virus interactions with host cells to identify circumstances where MRV effectiveness in tumor killing can be improved. In this review, we will discuss the ISR, MRV modulation of the ISR, and discuss ways in which MRV interaction with the ISR may increase the effectiveness of cancer therapeutics whose modes of action are altered by the ISR.
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Zetsche, Oliver Tobias. "Lernen in der Forensik." arbeitstitel | Forum für Leipziger Promovierende 6, no. 2 (February 24, 2015): 61–63. http://dx.doi.org/10.36258/aflp.v6i2.3298.
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Obwohl in den Standardwerken der forensisch-psychiatrischen Literatur auf die Bedeutung der schulischen und beruflichen Nachreifung der Maßregelvollzugs-Patienten hingewiesen wird, verläuft die Ausführung – gerade vor dem Hintergrund der Delinquenz begünstigenden Sozialisationsdefizite – jedoch meist nur beiläufig in randständigen Kapiteln. Obwohl sich für viele im Maßregelvollzug (MRV) Untergebrachte erstmals die Möglichkeit einer erfolgreichen Ausbildung eröffnet, da ein großer Teil der Patienten erst durch die Behandlung im MRV empfänglich für Bildungsmaßnahmen wird, gestalten sich die Bildungsangebote im MRV in Deutschland so dürftig, dass sie den enormen und tatsächlichen Bildungsbedarf vieler Patienten nicht annähernd decken können und eine bedarfsgerechte Weiterentwicklung dringend erforderlich ist. Aufgrund der meist nur lokal durchgeführten Studien fehlen dem überschaubaren Literaturrepertoire aussagekräftige Zahlen und Fakten. Die hier präsentierte Studie möchte daher versuchen, diese Lücke zu schließen, indem ein umfassendes Abbild des Arbeitsgebiets der pädagogischen Hilfsmaßnahmen im Rahmen der Maßregelvollzugsbehandlung skizziert, Möglichkeiten und Grenzen der Implementierung von pädagogischer Therapie aufgezeigt und die Notwendigkeit von pädagogischen Bildungsangeboten im MRV sowie die Sinnhaftigkeit dieser Behandlungsform diskutiert werden sollen.
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Hatano, Koji, Junichiro Tanaka, Yasutomo Nakai, Masashi Nakayama, Ken-ichi Kakimoto, Katsuyuki Nakanishi, and Kazuo Nishimura. "Utility of index lesion volume assessed by multiparametric MRI combined with Gleason grade for assessment of lymph node involvement in patients with high-risk prostate cancer." Japanese Journal of Clinical Oncology 50, no. 3 (December 12, 2019): 333–37. http://dx.doi.org/10.1093/jjco/hyz170.
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Abstract Purpose We examined the potential predictors of lymph node involvement and evaluated whether index lesion volume assessed using multiparametric magnetic resonance imaging is associated with lymph node involvement among patients with high-risk prostate cancer. Methods Extended pelvic lymph node dissection was used to evaluate patients with lymph node involvement. We retrospectively analyzed consecutive 102 patients with high-risk prostate cancer who underwent extended pelvic lymph node dissection at our institution between 2011 and 2017. To evaluate the index lesion volume at multiparametric magnetic resonance imaging (mrV), lesions were manually contoured on each T2-weighted axial slice in combination with diffusion-weighted and dynamic contrast-enhanced magnetic resonance imaging and integrated using image analysis software. Logistic regression analysis was performed to identify predictors of lymph node involvement. Results The median mrV was 1.4 ml (range 0–30.1 ml), and the median number of resected lymph nodes was 14 (range 7–38). Among 102 patients, 28 (28%) had lymph node involvement. Multivariate analysis identified significant predictors of lymph node involvement as follows: biopsy Gleason-grade group 5 (odds ratio = 17.2; 95% confidence interval, 2.1–299.0; P = 0.005), preoperative mrV (odds ratio = 1.14; 95% confidence interval, 1.02–1.30; P = 0.025) and percentage of positive cores with highest Gleason-grade group (odds ratio = 1.05; 95% confidence interval, 1.01–1.10; P = 0.005). Lymph node involvement was prevalent (69%) among tumors with Gleason-grade group 5 and mrV ≥3.4 ml, but was infrequently (10%) present among tumors with Gleason-grade group ≤4 and mrV <3.4 ml. Conclusions The combination of biopsy Gleason-grade and mrV may serve as a useful tool to stratify patients according to their risk of nodal metastases.
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Kim, Raehyun, Dong-hwan Kim, Seongsil Cho, Eunho Choi, Jinwoo Park, Sue Kyoung Lee, and Yowhan Son. "Assessment of REDD+ MRV Capacity in Developing Countries and Implications under the Paris Regime." Land 10, no. 9 (September 7, 2021): 943. http://dx.doi.org/10.3390/land10090943.
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The United Nations Framework Convention on Climate Change (UNFCCC) recognized the importance of forests in combating climate change and agreed upon financial support for REDD+ activities in developing countries through the Warsaw REDD+ Framework (WRF). The REDD+ activities for conserving carbon stored in forests to reduce GHG emissions and to enhance the carbon sink function of forests are expected to serve as an important means for achieving the climatic goal. In this study, a set of criteria was devised to assess the REDD+ Measuring, Reporting, and Verifying (MRV) implementation capabilities of developing countries, which was applied to analyze the REDD+ MRV levels in REDD+ countries. Based on the Forest Reference Emission Level/Forest Reference Level (FREL/FRL), National Strategy (NS), National Forest Monitoring System (NFMS) and Safeguard Information Summary (SIS) the countries submitted, 36 REDD+ countries submitted only the FREL/FRL (Group I), while 5 countries fulfilled the WRF requirements and registered REDD+ reduction results (Group II), and 6 received Results-Based Payments (RBP) (Group III). From longest to shortest, the periods for which the International Fund provided support were arranged in the order of Group III, II, and I, verifying the relative importance of international support. From highest to lowest, the overall MRV capability was also arranged in the order of Group III, II, and I, although Group I or Group II was at a higher level than the other groups in some elements. REDD+ countries in the Readiness Phase (Group I) would aim to have the MRV capabilities of Groups II and III to receive RBP, and international support for REDD+ MRV capacity building could enable them to do. However, in addition to the receipt of RBP, REDD+ should be reflected in the Nationally Determined Contribution (NDC) as consistent reduction results at the national GHG inventory level, and the advancement of REDD+ MRV is expected to be a necessary and sufficient condition for REDD+ cooperation under the Paris Agreement cooperative approach framework. For the following groups, international cooperation is essential. Countries in the Readiness Phase need to be supported with the establishment of an MRV framework, which will enable them to achieve REDD+ to receive RBP and be reflected in NDCs. For REDD+ countries that have thus far met the WRF requirements, the REDD+ scope needs to be upscaled to national levels, and the MRV system should be further advanced to establish a cooperative approach system that can achieve more ambitious reduction targets through forests.
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Vasić, Goran, Nebojša Trajković, Draženka Mačak, Tine Sattler, Peter Krustrup, Nikola Starčević, Goran Sporiš, and Špela Bogataj. "Intensity-Modified Recreational Volleyball Training Improves Health Markers and Physical Fitness in 25–55-Year-Old Men." BioMed Research International 2021 (June 18, 2021): 1–9. http://dx.doi.org/10.1155/2021/9938344.
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The present study is aimed at determining the effects of intensity-modified recreational volleyball training on health markers and physical fitness in healthy middle-aged men. Thirty-four healthy untrained men aged 25–55 years were randomized to either a modified recreational volleyball group (MRV, n = 17 ) or a recreational volleyball group (RV, n = 17 ). Both groups performed volleyball training twice a week over 12 weeks, with participants in MRV playing a modified game with higher intensity due to shorter breaks between rallies. The small to moderate improvements of both groups were observed in SBP (MRV g av = − 0.50 [-0.67, -0.33] vs. RV g av = − 0.37 [-0.55, -0.20]) to a similar extent ( p = 0.12 ). However, only the MRV significantly improved ( p < 0.001 ) the mean body weight ( g av = − 0.35 [-0.52, -0.18]) and BMI ( g av = − 0.39 [-0.56, -0.22]) to a moderate extent and the YYIR1 performance ( g av = 2.45 [2.22, 2.69]) to a large extent. Even though both groups significantly improved the rest HR, the mean change of rest HR was significantly greater in MRV as compared to the RV ( p < 0.001 , ŋ p 2 = 0.47 ). The study revealed that an intensity-modified type of recreational volleyball, involving shorter breaks between rallies, improves cardiorespiratory fitness and health markers for men aged 25–55 years.
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Chen, Hsian-Min, Clayton Chi-Chang Chen, Fong Y. Tsai, Cherng-Gueih Shy, Chen-Hoa Wu, Wen-Shien Chen, and Hao-Chun Hung. "Cerebral Sinovenous Thrombosis." Interventional Neuroradiology 14, no. 2_suppl (November 2008): 35–40. http://dx.doi.org/10.1177/15910199080140s208.
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Cerebral sinovenous thrombosis (CSVT) is an uncommon disorder that affects the dural venous sinus and cerebral vein. In our study, thirty-four patients were examined. Pre and/or post contrast-enhanced CT was done in 28 patients. MRI studies were done in 24 patients. 2-D TOF MR venography (MRV) and contrast-enhanced MRV (CEMRV) were done in 19 cases. Digital subtraction angiography (DSA) was done in 18 patients. Sixteen patients received systemic intravenous heparinization, and 12 received endovascular thrombolytic treatment with urokinase combined with anticoagulant therapy. Neuroimages of CSVT can be acquired by direct visualization of the thrombus within the dural sinus or by parenchymal changes secondary to venous occlusion. As there are some pitfalls to MRI in the diagnosis of CSVT, the combination of MRI and MRV is now the gold standard in the diagnosis of CSVT. Usually, accuracy can be improved by applying 2-D TOF MRV and CE MRV. Furthermore, the source image of MRV is critical in differentiating between normal sinus variations and diseased ones. DSA is the best tool for demonstrating dynamic intracranial circulation in CSVT and mostly is used for endovascular treatment. Systemic intravenous anticoagulant therapy with heparin is accepted as a first line treatment. Except for clinical manifestations after systemic heparinization, abnormal MR findings of parenchymal change can be used to determine when to initiate thrombolytic treatment. Endovascular therapy can be finished at the ante-grade flow within the dural sinus and continuous anticoagulation is sufficient to facilitate clinical improvement. Clinical suspicion and excellent neuroimaging are crucial in making the diagnosis of CSVT. Proper management with anticoagulants and/or endovascular thrombolytic therapy is mandatory in preventing propagation of the thrombosis and improving the clinical outcome.
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Gonzalez, Carlos. "EU MRV Regulation - KYMA’s Solution." Marine Engineering 53, no. 5 (September 1, 2018): 646–51. http://dx.doi.org/10.5988/jime.53.646.
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Male, Christoph, Donald L. Yee, Christian Loewe, Rajesh Krishnamurthy, Elizabeth Chalmers, Jane Newburger, Luz-Margarita Ramirez, Ronald Portman, and Lesley G. Mitchell. "Comparison Of Ultrasound Versus Magnetic Resonance Venography For Diagnosis Of Catheter-Related Thrombosis In Children: A Multicenter Multinational Study." Blood 122, no. 21 (November 15, 2013): 2377. http://dx.doi.org/10.1182/blood.v122.21.2377.2377.
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Abstract Background Venous thrombotic events (VTE) in children are related to central venous catheters and occur predominantly in the upper venous system. In routine clinical practice, ultrasound (US) is the most frequently used imaging technique for diagnosis of VTE in children because of its ease of use and non-invasiveness. However, US is known to be relatively insensitive for detection of VTE in the central upper venous system. Magnetic resonance venography (MRV) is a promising alternative as MRV can comprehensively image the central venous system, is minimally invasive and does not involve radiation. However, MRV involves high technical and logistic demands, and requires sedation in young children. Objectives To compare the feasibility and diagnostic accuracy of US and MRV for diagnosis of central venous catheter related VTE in children. Methods Study Design: Cross-sectional diagnostic study. Study population: Children 0-<18 years of age with a central venous catheter in place for any reason were recruited prospectively and consisted of i) children who are asymptomatic for VTE: children who were screened for central venous catheter-related VTE within 20-60 days of catheter placement ii) children who are symptomatic for VTE: children presenting with signs and symptoms of central venous catheter related VTE within 7 days of symptom onset (all study-related imaging tests were completed within this time period). Children were excluded in case of i) systemic anticoagulant or antiplatelet therapy, and ii) inability to undergo contrast MRV. Imaging tests: Each participant had three imaging tests performed i) Doppler compression US ii) MRV without contrast iii) MRV with gadolinium contrast. All imaging studies were performed within 48 hours of each other. Data collection included clinical and demographic information on each subject, imaging and video documentation of each US and MRV. Central Adjudication Committee: All imaging studies were blinded and independently reviewed and interpreted by a central adjudication committee for the presence or absence of VTE. Outcomes: The two main study outcomes were 1) Feasibility of performing each test: assessed by a) the number of children who completed each diagnostic study and b) the number of evaluable studies; and 2) Diagnostic accuracy of each diagnostic test: assessed by the proportion of VTE identified by the respective test in relation to the total number of VTE identified by any imaging modality. Results A total of 152 children were enrolled from 24 centers in 9 countries: Argentina, Brazil, Mexico, United States, Canada, United Kingdom, Netherlands, Austria and Germany. The median age (range) for children was 11 years (2 months to 17 years). Fourteen (9.2%) children had clinical symptoms of VTE. One hundred and thirty three (88%) children had US completed, 113 (74%) had MRV without contrast and 113 (74%) had MRV with contrast. 18 subjects withdrew from the study before any test was performed for various reasons. Adjudication and analysis are ongoing, and will be completed by October 14th, 2013. Therefore, final results regarding the feasibility and diagnostic accuracy of each test will be available at the time of presentation. Conclusion We have completed the largest and most comprehensive study to date comparing the feasibility and diagnostic accuracy of currently available non-invasive imaging modalities for detecting central venous catheter related VTE in children. Ultrasound demonstrated better feasibility than MRV, however, MRV still proved feasible in nearly three-quarters of pediatric subjects and was performed without sedation in individuals as young as 2 months old. The overall feasibility and diagnostic accuracy of each test will be reported after final adjudication and analysis are complete. The study findings will be used to formulate an effective pediatric diagnostic algorithm for diagnosis of central venous catheter-related VTE. The algorithm will be used as guidance for clinical practice as well as outcome assessments for clinical trials of antithrombotic agents in children. Disclosures: Male: Bristol Myer Squibb: Consultancy. Yee:Bristol Myer Squibb: Research Funding. Loewe:Bristol Myer Squibb: Consultancy. Krishnamurthy:Koninklijke Philips NV: Research Funding; Bristol Myer Squibb: Consultancy. Chalmers:Bristol Myer Squibb: Consultancy. Newburger:Merck: Consultancy; Janssen Pharmacutical: Consultancy; Bristol Myer Squibb: Consultancy. Ramirez:Bristol Myer Squibb: Employment. Portman:Bristol Myer Squibb: Employment. Mitchell:Bristol Myer Squibb: Consultancy; Eisai: Consultancy; Boehringer Ingelheim: Consultancy.
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Manandhar, Ugan. "Forest Monitoring, Measurement, Reporting and Verification: from Principle to Practice." Journal of Forest and Livelihood 11, no. 2 (September 14, 2013): 46–54. http://dx.doi.org/10.3126/jfl.v11i2.8621.
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Under the United Nations Framework Convention on Climate Change (UNFCCC), many tropical developing countries have agreed to participate in the Reducing Emissions from Deforestation and Forest Degradation as well as conservation and enhancement of carbon stocks and sustainable management of forests (REDD+) programme so as to receive payments for their contribution in reducing emissions from forestry sector. The emission reduction is measured in terms of quantifications of carbon dioxide (CO2) equivalent, upon which payments are made. To quantify emissions in terms of CO2 equivalent, a process called measurement/monitoring, reporting and verification (MRV) has been developed, which forms the backbone of performance-based payment under the REDD+ mechanism. This paper primarily reviews the principles and methods of MRV. By taking the case of the Terai Arc Landscape (TAL) of Nepal, a sub-national level proposed project, the paper demonstrates how an institutional mechanism for MRV can be designed and practiced at national level considering national circumstances and existing institutions. Also, the cost effectiveness and transparency of the MRV process are identified as important elements. DOI: http://dx.doi.org/10.3126/jfl.v11i2.8621 Journal of Forestry and Livelihood Vol.11(2) 2013 46-54
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Arnaboldi, Sara, Francesco Righi, Virginia Filipello, Tiziana Trogu, Davide Lelli, Alessandro Bianchi, Silvia Bonardi, Enrico Pavoni, Barbara Bertasi, and Antonio Lavazza. "Mammalian Orthoreovirus (MRV) Is Widespread in Wild Ungulates of Northern Italy." Viruses 13, no. 2 (February 3, 2021): 238. http://dx.doi.org/10.3390/v13020238.
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Mammalian orthoreoviruses (MRVs) are emerging infectious agents that may affect wild animals. MRVs are usually associated with asymptomatic or mild respiratory and enteric infections. However, severe clinical manifestations have been occasionally reported in human and animal hosts. An insight into their circulation is essential to minimize the risk of diffusion to farmed animals and possibly to humans. The aim of this study was to investigate the presence of likely zoonotic MRVs in wild ungulates. Liver samples were collected from wild boar, red deer, roe deer, and chamois. Samples originated from two areas (Sondrio and Parma provinces) in Northern Italy with different environmental characteristics. MRV detection was carried out by PCR; confirmation by sequencing and typing for MRV type 3, which has been frequently associated with disease in pigs, were carried out for positive samples. MRV prevalence was as high as 45.3% in wild boars and 40.6% in red deer in the Sondrio area, with lower prevalence in the Parma area (15.4% in wild boars). Our findings shed light on MRV occurrence and distribution in some wild species and posed the issue of their possible role as reservoir.
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Gandhoke, Gurpreet S., Paolo Frassanito, Nagesh Chandra, Bal K. Ojha, and Anoop Singh. "Role of magnetic resonance ventriculography in multiloculated hydrocephalus." Journal of Neurosurgery: Pediatrics 11, no. 6 (June 2013): 697–703. http://dx.doi.org/10.3171/2013.2.peds12456.
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Object In this paper the authors' goal was to investigate the clinical usefulness of Gd-enhanced MR ventriculography (MRV) in pediatric patients affected by multiloculated hydrocephalus. Methods Eighteen patients (11 boys and 7 girls, age range 2–14 months) with a diagnosis of multiloculated hydrocephalus were included in the study. After injection of gadodiamide (0.02–0.04 mmol) into the lateral ventricle by tapping the anterior fontanel, sagittal, coronal, and axial T1-weighted MR images were acquired. The location of the septations and the sites of obstruction of CSF flow were assessed. Postoperative MRV was obtained to confirm the results of endoscopic treatment in most complex cases. Results No adverse events were observed after injection of contrast medium into the ventricular system. Preoperative MRV accurately defined the exact morphology of septae and ventricular walls in all cases. In 1 case the diagnosis of multiloculated hydrocephalus was ruled out. Sites of obstruction of CSF flow within the ventricular system were also well established. In 4 cases the multiple compartments were proven to intercommunicate. Postoperative MRV was useful in assessing the functional status of third ventriculostomy, aqueductoplasty, and other endoscopic fenestrations. Conclusions Magnetic resonance ventriculography is a safe, effective, and reliable technique. The accurate definition of the anatomy of the ventricles and the site of obstruction in multiloculated hydrocephalus can help to plan the most appropriate treatment and minimize the number of procedures. Although MRV is also useful during postoperative follow-up to determine the results of endoscopic treatment, it should be limited to particularly complex cases, due to its invasiveness.
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Lim, Ruth P., Emma Hornsey, Dinesh Ranatunga, Huming Hao, Julie Smith, Tim Spelman, Jason Chuen, and Mark Goodwin. "Upper extremity non-contrast magnetic resonance venography (MRV) compared to contrast enhanced MRV and ultrasound." Clinical Imaging 45 (September 2017): 51–57. http://dx.doi.org/10.1016/j.clinimag.2017.05.020.
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Ozturk, Kerem, Esra Soylu, and Mufit Parlak. "Dural venous sinus thrombosis: The combination of noncontrast CT, MRI and PC-MR venography to enhance accuracy." Neuroradiology Journal 31, no. 5 (June 5, 2018): 473–81. http://dx.doi.org/10.1177/1971400918781969.
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Aim The aim of this article is to determine whether a combination of noncontrast CT (NCCT), three-dimensional-phase contrast magnetic resonance venography (3D PC-MRV), T1- and T2-weighted MRI sequences can help to identify acute and subacute dural venous sinus thrombosis (DVST) with greater accuracy. Methods A total of 147 patients with DVST ( n = 30) and a control group ( n = 117) underwent NCCT, T1- and T2-weighted MRI sequences, and 3D PC-MRV from 2012 to 2016. Two experienced observers interpreted the images retrospectively for the presence of DVST. Nonvisualization of the dural venous sinuses on 3D PC-MRV and signal changes supporting acute or subacute thrombus on T2- and T1-weighted images were considered a direct sign of DVST. Also, using circle region of interest (ROI) techniques, attenuation measurement from each sinus was obtained on NCCT. Sensitivity and specificity were computed for these modalities separately and in combination for diagnosis of DVST using digital subtraction angiography as the reference standard. Results Nonvisualization of venous sinuses on 3D PC-MRV (sensitivity 100%, specificity 71%) in combination with both applying Hounsfield unit (HU) threshold values of greater than 60 on NCCT (sensitivity 70%, specificity 94%) and acquiring signal changes supporting DVST on T2- and T1-weighted images (sensitivity 83%, specificity 96%), were found to have 100% sensitivity and 100% specificity in the identification of acute or subacute DVST. Conclusion The combination of NCCT, T1- and T2-weighted MRI and 3D PC-MRV may allow the diagnosis of acute or subacute DVST and may obviate the need for contrast usage in patients with renal impairment or contrast allergies.
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Martin, Nancy, Anthony L. Traboulsee, Lindsay Machan, Darren Klass, Tasha Ellchuk, Yinshan Zhao, Katherine B. Knox, et al. "Prevalence of Extracranial venous Narrowing on Magnetic Resonance Venography is Similar in People with Multiple Sclerosis, Their Siblings, and Unrelated Healthy Controls: A Blinded, Case-Control Study." Canadian Association of Radiologists Journal 68, no. 2 (May 2017): 202–9. http://dx.doi.org/10.1016/j.carj.2016.07.002.
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Purpose The study sought to assess and compare the prevalence of narrowing of the major extracranial veins in subjects with multiple sclerosis and controls, and to assess the sensitivity and specificity of magnetic resonance venography (MRV) for describing extracranial venous narrowing as it applies to the chronic cerebrospinal venous insufficiency theory, using catheter venography (CV) as the gold standard. Methods The jugular and azygos veins were assessed with time-of-flight MRV in this assessor-blinded, case-control study of subjects with multiple sclerosis, their unaffected siblings, and unrelated controls. The veins were evaluated by diameter and area, and compared with CV. Collateral vessels were also analyzed for maximal diameter, as a potential indicator of compensatory flow. Results A high prevalence of extracranial venous narrowing was demonstrated in all study groups, collectively up to 84% by diameter criteria and 90% by area, with no significant difference between the groups when assessed independently ( P = .34 and .63, respectively). There was high interobserver variability in the reporting of vessel narrowing (kappa = 0.32), and poor vessel per vessel correlation between narrowing on MRV and CV (kappa = 0.064). Collateral neck veins demonstrated no convincing difference in maximum size or correlation with jugular narrowing. Conclusion There is a high prevalence of narrowing of the major extracranial veins on MRV in all 3 study groups, with no significant difference between them. These findings do not support the chronic cerebrospinal venous insufficiency theory. Although MRV has shown a high sensitivity for identifying venous narrowing, time-of-flight imaging demonstrates poor interobserver agreement and poor specificity when compared with the gold standard CV.
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Brod, Staley A., Larry A. Kramer, Alan M. Cohen, Andrew D. Barreto, Thanh-Tung Bui, James R. Jemelka, Kelly Ton, et al. "Chronic cerebrospinal venous insufficiency: masked multimodal imaging assessment." Multiple Sclerosis Journal 19, no. 11 (July 4, 2013): 1499–507. http://dx.doi.org/10.1177/1352458513494493.
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Background: Chronic cerebrospinal venous insufficiency (CCSVI) was implicated in the pathophysiology of multiple sclerosis (MS). Objective: We evaluated neurosonography (NS), magnetic resonance venography (MRV), and transluminal venography (TLV) in subsets of MS patients drawn from a single-center, prospective, case-control study of 206 MS and 70 non-MS volunteers. Methods: As previously reported, findings on high-resolution B-mode NS imaging with color and spectral Doppler of the extracranial and intracranial venous drainage consistent with CCSVI were similar among MS and non-MS volunteers (3.88% vs 7.14%; p = 0.266). Ninety-nine MS participants consented to intravascular contrast-enhanced 3D MRV to assess their major systemic and intracranial venous circulation, and 40 advanced to TLV that included pressure measurements of the superior vena cava, internal jugular, brachiocephalic, and azygous veins. Results: NS findings and MRV patterns were discrepant for 26/98 evaluable subjects, including four with abnormal findings on NS that had normal venous anatomy by MRV. In no instance were TLV pressure gradients indicative of clinically significant functional stenosis encountered. The three imaging approaches provided generally consistent data with discrepancies referable to inherent technique properties. Conclusions: Our findings lend no support for altered venous outflow dynamics as common among MS patients, nor do they likely contribute to the disease process.
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Chamuleau, Steven A. J., Maria Siebes, Martijn Meuwissen, Karel T. Koch, Jos A. E. Spaan, and Jan J. Piek. "Association between coronary lesion severity and distal microvascular resistance in patients with coronary artery disease." American Journal of Physiology-Heart and Circulatory Physiology 285, no. 5 (November 2003): H2194—H2200. http://dx.doi.org/10.1152/ajpheart.01021.2002.
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Homogeneity of microvascular resistance in different perfusion areas of the same heart is generally assumed. We investigated the effect of the severity of an epicardial stenosis on microvascular resistance in 27 patients with coronary artery disease and stable angina. All patients had an angiographically normal coronary artery, an artery with an intermediate lesion, and an artery with a severe lesion; the latter was treated with angioplasty. In each patient, distal blood flow velocity and pressure were measured during baseline and maximal hyperemia (induced by intracoronary adenosine) using a Doppler and pressure guide wire, respectively. The ratio of mean distal pressure to average peak blood flow velocity was used as an index for the microvascular resistance (MRv). Within patients, the hyperemic MRv was higher in arteries with more severe stenosis ( P = 0.021). After percutaneous transluminal coronary angioplasty (PTCA), the hyperemic MRv decreased (pre-PTCA, 2.6 vs. post-PTCA, 1.9 mmHg·cm–1s–1, P < 0.01) toward the value of the reference artery (1.7 mmHg·cm–1s–1; P = 0.67). We conclude that there is a positive association between coronary lesion severity and variability of distal microvascular resistance that normalizes after angioplasty. This study challenges the concept of uniform distribution of hyperemic MRv that is relevant for the interpretation of both noninvasive and invasive diagnostic tests.
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Resorlu, Mustafa, Abdullah Sariyildirim, Berkan Resorlu, Eyup Burak Sancak, Fatma Uysal, Gurhan Adam, Alpaslan Akbas, et al. "Association of Congenital Left Renal Vein Anomalies and Unexplained Hematuria: Multidetector Computed Tomography Findings." Urologia Internationalis 94, no. 2 (August 14, 2014): 177–80. http://dx.doi.org/10.1159/000365664.
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Objectives: To investigate whether congenital renal vein anomalies are involved in the etiology of hematuria by analyzing abdominal multidetector computed tomography (MDCT) results. Methods: Six hundred and eighty patients undergoing MDCT for various abdominal pathologies in whom possible causes of hematuria were excluded were retrospectively assessed in terms of left renal vein anomalies, such as circumaortic left renal vein (CLRV), retroaortic left renal vein (RLRV) and multiple renal vein (MRV). Patients with CLRV, RLRV or MRV and patients with normal left renal veins were compared in terms of the presence of hematuria. Results: Left renal vein anomalies were detected in 100 patients (14.7%). RLRV, CLRV and MRV were identified in 5.4, 2.5 and 6.8% of patients, respectively. Hematuria was determined in 8.1% of patients with an RLRV anomaly and in 10.5% of patients with no RLRV anomaly (p = 0.633). Hematuria was detected in 23.5% of patients with a CLRV anomaly and 10.1% of those without (p = 0.074), and in 21.7% of patients with an MRV anomaly and 9.6% of those without (p = 0.009). Conclusions: In addition to increasing risk of complication during retroperitoneal surgery, numeric congenital renal vein anomalies are also significant in terms of leading to clinical symptoms such as hematuria.
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Miller, Cathy L., Michelle M. Arnold, Teresa J. Broering, Craig E. Hastings, and Max L. Nibert. "Localization of Mammalian Orthoreovirus Proteins to Cytoplasmic Factory-Like Structures via Nonoverlapping Regions of μNS." Journal of Virology 84, no. 2 (November 4, 2009): 867–82. http://dx.doi.org/10.1128/jvi.01571-09.
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ABSTRACT Virally induced structures called viral factories form throughout the cytoplasm of cells infected with mammalian orthoreoviruses (MRV). When expressed alone in cells, MRV nonstructural protein μNS forms factory-like structures very similar in appearance to viral factories, suggesting that it is involved in forming the structural matrix of these structures. μNS also associates with MRV core particles; the core proteins μ2, λ1, λ2, λ3, and σ2; and the RNA-binding nonstructural protein σNS. These multiple associations result in the recruitment or retention of these viral proteins or particles at factory-like structures. In this study, we identified the regions of μNS necessary and sufficient for these associations and additionally examined the localization of viral RNA synthesis in infected cells. We found that short regions within the amino-terminal 220 residues of μNS are necessary for associations with core particles and necessary and sufficient for associations with the proteins μ2, λ1, λ2, σ2, and σNS. We also found that only the λ3 protein associates with the carboxyl-terminal one-third of μNS and that viral RNA is synthesized within viral factories. These results suggest that μNS may act as a cytoplasmic scaffolding protein involved in localizing and coordinating viral replication or assembly intermediates for the efficient production of progeny core particles during MRV infection.
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Glover, Kathleen K. M., Danica M. Sutherland, Terence S. Dermody, and Kevin M. Coombs. "A Single Point Mutation, Asn16→Lys, Dictates the Temperature-Sensitivity of the Reovirus tsG453 Mutant." Viruses 13, no. 2 (February 12, 2021): 289. http://dx.doi.org/10.3390/v13020289.
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Studies of conditionally lethal mutants can help delineate the structure-function relationships of biomolecules. Temperature-sensitive (ts) mammalian reovirus (MRV) mutants were isolated and characterized many years ago. Two of the most well-defined MRV ts mutants are tsC447, which contains mutations in the S2 gene encoding viral core protein σ2, and tsG453, which contains mutations in the S4 gene encoding major outer-capsid protein σ3. Because many MRV ts mutants, including both tsC447 and tsG453, encode multiple amino acid substitutions, the specific amino acid substitutions responsible for the ts phenotype are unknown. We used reverse genetics to recover recombinant reoviruses containing the single amino acid polymorphisms present in ts mutants tsC447 and tsG453 and assessed the recombinant viruses for temperature-sensitivity by efficiency-of-plating assays. Of the three amino acid substitutions in the tsG453 S4 gene, Asn16-Lys was solely responsible for the tsG453ts phenotype. Additionally, the mutant tsC447 Ala188-Val mutation did not induce a temperature-sensitive phenotype. This study is the first to employ reverse genetics to identify the dominant amino acid substitutions responsible for the tsC447 and tsG453 mutations and relate these substitutions to respective phenotypes. Further studies of other MRV ts mutants are warranted to define the sequence polymorphisms responsible for temperature sensitivity.
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Di Berardino, Federica, Dario Carlo Alpini, Pietro Maria Bavera, Piero Cecconi, Mario Farabola, Valentina Mattei, Umberto Ambrosetti, and Antonio Cesarani. "Chronic cerebrospinal venous insufficiency in Ménière disease." Phlebology: The Journal of Venous Disease 30, no. 4 (March 4, 2014): 274–79. http://dx.doi.org/10.1177/0268355514526871.
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Objectives The aim of this study was to focus on patients suffering from cochleo-vestibular disorder with and without Ménière disease (MD) in order to verify whether chronic cerebrospinal drainage abnormalities could play a role in the etiopathogenesis of endolymphatic hydrops. Methods Fifty-two volunteers were enrolled and subdivided into two groups: 24 definite MD and 28 not-MD. Both magnetic resonance venography imaging with contrast-enhanced imaging of the venous cerebrospinal system (MRV) and venous echo-color Doppler (ECD) were performed. Results MRV showed abnormalities in 83% of MD and 57% of not-MD subjects ( p < 0.001). Asymmetrical cervical venous flow, assessed by MRV, was confirmed by ECD in 62.5% of MD but in only 21.5% of not-MD subjects ( p<0.001). Conclusion Chronic cerebrospinal venous insufficiency might be the anatomical background, which provides a predisposing factor for the development of endolymphatic hydrops in MD patients.
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Harada, Tomohiro. "Outline and Requirements of EU MRV." Marine Engineering 53, no. 5 (September 1, 2018): 620–26. http://dx.doi.org/10.5988/jime.53.620.
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Simon-Lopez, Ramon, Elena Sukhacheva, Nina Tsvetaeva, Marina Egorova, Sergey Kolenkin, and Tatjana Achildieva. "High Sensitivity New Parameters for the Detection of Vitamin B12 and Folate Deficiencies." Blood 112, no. 11 (November 16, 2008): 5379. http://dx.doi.org/10.1182/blood.v112.11.5379.5379.
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Abstract The classical flow charts used widely for the diagnostic approach of anemia due to Vitamin B12 (B12) deficiency or Anemia due Folate deficiency includes the Mean cell Volume of the red blood cells (MCV) as one of the key tests for the suspicion of these diseases and the differential diagnosis of anemia. In our experience, only around half of the patients with B12 deficiency (B12) or Folate deficiency have high MCV, in many of the situations because the coexistence of other causes of anemia. The majority of the actual hematology analyzers provide information about Red cell size (MCV), Reticulocyte Volume (MRV) and Platelet Volume (MPV) Recent hematology instruments provide research data about the size of some of the White Blood Cells (WBC) as the LH700 Series from Beckman Coulter We designed a study to find which tests can help to improve the detection/flagging of these deficiencies. We collected blood samples from 58 individuals that came to the hospital and were considered as normals by the physicians. We collected 108 cases with anemia defined according the WHO anemia criteria (Hb<12 g/dL in women and Hb<13 g/dL in men.) from the hospital laboratory samples. The WHO criteria of anemia was the only condition considered. After this, samples were randomly selected from the anemic patients. We analyzed in both groups the CBC-Diff, the reticulocyte %, # and Reticulocyte related parameters, WBC Research Population Data, Serum Iron, Serum Ferritin, B12, Serum Folate, RBC Folate, Serum EPO, Transferrin, CRP, and Intrinsic Factor Antibody and checked the efficiency of the hematological parameters and research data (Mean Volume of Neutrophils and Monocytes) to detect the presence of B12 deficiency, Folate deficiency or both. We have compared B12 and Folate deficiencies with normals and also with the rest of anemias, looking for the different cut-off values in both situations. We also studied two patients with Serum B12 and Serum Folate deficiencies respectively, and followed over time the evolution of the previous tests listed above after a successful treatment. The study population included 82 males (49.4%) and 84 females (50.6%). We found that 5,2 % of the “normal” patients with normal Hemoglobin have B12 deficiency (B12 < 145 pg/mL) 5.2 % of the “normal” with normal Hemoglobin have intermediate values of B12 (B12 > 145 <180 pg/mL) and 3.45 % of the “normal” have low serum Folate. From the group of anemic patients, we found that the prevalence of B12 deficiency was 21/108= 19.4%, the prevalence of intermediate B12 was 3/108= 2.8%, the prevalence of serum folate deficiency was 10/108= 9.3%, and there were two cases with serum folate deficiency that also have respectively B12 deficiency (1/108= 0.9%) or B12 in intermediate values (1/108= 0.9%) B12 def vs Normals Mann Withney T-Test ROC AUC Sens Specif Cut.off signif.ROC MCV p=0.3156 p=0.9533 0.577 MPV p=0.0001 0.802 79.2 80.6 <8.3 p=0.0001 @NE Mean Volume p<0.0001 0.862 83.3 77.8 >140.3 p=0.0001 @MO Mean Volume p<0.0001 0.829 62.5 88.9 >172.3 p=0.0001 MRV p=0.0113 0.705 50 96.4 >113.3 p=0.0051 Folate def vs Normals Mann Withney T-Test ROC AUC Sens Specif Cut-off signif.ROC MCV p=0.0798 p=0.6461 0.665 MPV p<0.0001 0.832 81 80.6 <8.3 p=0.0001 @NE Mean Volume p=0.0008 0.87 95.2 69.4 >140.2 p=0.0001 @MO Mean Volume p=0.0002 0.801 66.7 83.3 >169.6 p=0.0001 MRV p=0.0054 0.731 47.6 96.4 >113.3 p=0.0019 The analytical sensitivity/sensitivity/cutoffs are specific for this study only. The @Mean Neutrophil Volume (@MNE V) and @Mean Monocyte Volume (@MMOV) may be used for the detection of megaloblastic neutrophils and monocytes. Megaloblastic Neutrophils and Megaloblastic monocytes may be seen in Megaloblastic anemias due to B12 and/or folate deficiency. MNEV and MMOV have significantly higher sensitivity than the previous information from the red cells (MCV) detecting B12 or folate deficiency because they are not affected by the presence at the same time of Iron deficiency or other reasons of anemia. @ Research use only parameters
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Chu, JY. "P.056 Intracranial hemorrhage as initial presentation of sagittal sinus thrombosis: review of 3 cases." Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques 44, S2 (June 2017): S27. http://dx.doi.org/10.1017/cjn.2017.140.
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Background: Intracranial hemorrhage due to sagittal sinus thrombosis is an unusal inital clinical presentation and a series of 3 cases is presented. Methods: A retrospective study of stroke patients seen at the William Osler Health System between 2014 -2016. Results: 1: 43 y.o. female presented with headaches and right hemiparesis. CT and MRI/MRV showed L. parietal intra-cerebral hemorrhage and sagittal and transverse sinus thrombosis. She was treated with IV heparin and subsequent oral Warfarin but developed symptomatic left subdural hematoma which was successfully evacuated. Hypercoagulable workup was negative. Subsequent MRI/MRV showed resolution of her sinus thrombosis and received asparin only since. 2: 45 y.o. male presented with generalized seizure 10 days following a motor vehicle accident. Initial CT showed focal right frontal subarachnoid hemorrhage and subsequent MRI/MRV confirmed extensive sagittal sinus thrombosis. He was treated with IV heparin and subsequent Warfarin without any complications. 3: 32 y.o. male presented with generalized seizure. CT and MRI/MRV confirmed a large right temporal lobe intra-cerebral hemorrhage and extensive right transverse sinus and straight sinus thrombosis. He was successfully treated with IV heparin followed by oral Warfarin. Conclusions: Despite intracranial hemorrhage in patients with cerebral sinus venous thrombosis, they could be managed successfully with anticoagulation therapy and with careful clinical and neuro-imaging monitoring.
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Kennedy, Michael D., and Gordon J. Bell. "Development of Race Profiles for the Performance of a Simulated 2000-m Rowing Race." Canadian Journal of Applied Physiology 28, no. 4 (August 1, 2003): 536–46. http://dx.doi.org/10.1139/h03-041.
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The purpose of this study was to determine the race profile for a 2000-m simulated rowing race as well as the effect of training and gender on the race profile. Nineteen men and 19 women undertook a 2000-m simulated rowing race before and after 10 weeks of a typical off-season training program for rowing. Velocity was calculated every 200 m and the deviation in velocities from the mean race velocity (MRV) was plotted every 200 m to produce race profiles for each gender before and after training. The three fastest male rowers varied approximately 0.02 m•s−1 from the MRV after training and displayed a constant-pace model. The fastest female rowers displayed an all-out strategy after training, producing large deviations from MRV. Average squared deviations from the mean (SDM) determined that all groups except the fastest females had a reduction in MRV deviation after training. These results suggest that the optimal race profile for a simulated 2000-m rowing race may be different between genders. Training reduces SDM and influences both male and female pacing patterns such that both exhibit a pacing strategy that is more similar to that of elite athletes in other events of similar and shorter duration. Key words: maximal oxygen consumption, critical power, pacing strategy, critical velocity, accumulated oxygen deficit
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Rada Alshamari, Murdhy, and Manal Saleh Alghannam. "Marking Mirativity in Syntax: Minimalsit Mechanisms." Advances in Language and Literary Studies 12, no. 4 (August 31, 2021): 155. http://dx.doi.org/10.7575/aiac.alls.v.12n.4.p.155.
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This paper offers a generative minimalist investigation to the derivation and interpretation of mirativity information in Central Najdi Arabic (CNA), arguing that grammar of CNA morphologically marks mirativity in syntax by means of the discourse particle wara. Implementing minimalist mechanisms (Chomsky 2001), it is shown that wara instantiates a functional, discoursal projection MrvP in the left periphery of the sentence, articulating the feature [Mrv] at the PF-interface. LF-interface analyses demonstrate that [Mrv] on wara is interpretable/valued, while the counterpart on the subject DP that wara marks is uninterpretable/unvalued. Agree between wara and the subject DP creates a PF-chain wara>SubjectClitic>SubjectDP that results in the subject DP being marked with and interpreted mirativity at LF-interface. Further explorations show that movement of the subject DP across wara is only legitimised if the subject DP has a discourse, information structural feature beyond [Mrv]. Evidence for this claim comes from the fact that when wara marks the subject DP with mirativity, the subject DP remains in situ. Thus, on minimalist empirical groundings, movement is argued to be motivated by interpretive reasons beyond mirativity. Further analyses show that Agree between wara and subject is of mutual manner; wara u-[φ]-probes the subject goal, while the goal seeks valuation of u-[Mrv] on it (Alshamari 2017).
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Hua, Lei, Harry Joe, and Haijun Li. "Relations Between Hidden Regular Variation and the Tail Order of Copulas." Journal of Applied Probability 51, no. 01 (March 2014): 37–57. http://dx.doi.org/10.1017/s0021900200010068.
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We study the relations between the tail order of copulas and hidden regular variation (HRV) on subcones generated by order statistics. Multivariate regular variation (MRV) and HRV deal with extremal dependence of random vectors with Pareto-like univariate margins. Alternatively, if one uses a copula to model the dependence structure of a random vector then the upper exponent and tail order functions can be used to capture the extremal dependence structure. After defining upper exponent functions on a series of subcones, we establish the relation between the tail order of a copula and the tail indexes for MRV and HRV. We show that upper exponent functions of a copula and intensity measures of MRV/HRV can be represented by each other, and the upper exponent function on subcones can be expressed by a Pickands-type integral representation. Finally, a mixture model is given with the mixing random vector leading to the finite-directional measure in a product-measure representation of HRV intensity measures.
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Hua, Lei, Harry Joe, and Haijun Li. "Relations Between Hidden Regular Variation and the Tail Order of Copulas." Journal of Applied Probability 51, no. 1 (March 2014): 37–57. http://dx.doi.org/10.1239/jap/1395771412.
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We study the relations between the tail order of copulas and hidden regular variation (HRV) on subcones generated by order statistics. Multivariate regular variation (MRV) and HRV deal with extremal dependence of random vectors with Pareto-like univariate margins. Alternatively, if one uses a copula to model the dependence structure of a random vector then the upper exponent and tail order functions can be used to capture the extremal dependence structure. After defining upper exponent functions on a series of subcones, we establish the relation between the tail order of a copula and the tail indexes for MRV and HRV. We show that upper exponent functions of a copula and intensity measures of MRV/HRV can be represented by each other, and the upper exponent function on subcones can be expressed by a Pickands-type integral representation. Finally, a mixture model is given with the mixing random vector leading to the finite-directional measure in a product-measure representation of HRV intensity measures.
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Osgood, Marcey, Elizabeth Budman, Raphael Carandang, Richard P. Goddeau, Jr., and Nils Henninger. "Prevalence of Pelvic Vein Pathology in Patients with Cryptogenic Stroke and Patent Foramen Ovale Undergoing MRV Pelvis." Cerebrovascular Diseases 39, no. 3-4 (2015): 216–23. http://dx.doi.org/10.1159/000376613.
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Background: A substantial proportion of ischemic strokes has no any identified underlying cause. Notably, the prevalence of a patent foramen ovale (PFO) is increased in cryptogenic stroke (CS) populations, which may serve as a conduit for paradoxical emboli originating from deep vein thrombosis (DVT) including the pelvic veins. Yet, there are no published guidelines for the assessment of pelvic veins as part of the stroke workup and few studies have systematically investigated pelvic veins as a potential source for paradoxical emboli in CS patients. Further, there is a relative paucity of data regarding pelvic DVT in CS and results have been conflicting. Hence, we sought to determine the prevalence of pelvic DVT in select CS patients with PFO who underwent magnetic resonance venography (MRV). Methods: We retrospectively identified patients (n = 50) who underwent contrast-enhanced pelvic MRV at the discretion of the treating physician for the evaluation of CS in the presence of a PFO during hospitalization at a single academic stroke center between January 2011 through December 2013. Multivariable logistic regression analyses were used to assess for factors independently associated with the presence of an abnormal MRV pelvis. Results: Patients (47 ± 13 years of age) had MRV performed 4 ± 3 days after their incident stroke. Nine patients had an abnormal MRV (18%). Of these, four (8%) had pelvic vein thrombosis and 5 (10%) a May-Thurner anatomic variant. All patients with pelvic DVT were subsequently anticoagulated with warfarin (none had abnormal hypercoagulability testing). Clinical clues suggesting paradoxical embolism were present in as many as 40% of patients. On multivariable logistic regression, a history of any risk factors predisposing to DVT (OR 6.7; coefficient 1.9; BCa 95% CI 0.08-20.2; p = 0.014) as well as the number of predisposing risk factors (OR 3.9; coefficient 1.4; BCa 95% CI 0.25-4.2; p = 0.005) predicted the presence of pelvic vein pathology on MRV. Conclusion: We demonstrate a relatively high prevalence of pelvic DVT among select CS patients emphasizing the importance of considering the pelvic veins as a potential source for emboli particularly in the presence of risk factors known to predispose DVT. Because patients were included at the treating physician's discretion, our results reflect ‘real-life' practice. Our results may be of clinical importance as inclusion of pelvic vein imaging in CS patients with PFO had impactful therapeutic and nosologic implications. Further study is needed to define patients most likely to benefit from pelvic vein imaging.
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Han, Hui, Zhibin Yao, Huaqiao Wang, Xuefei Deng, Amy Hui Yu Fong, and Ming Zhang. "Dural Entrance of the Bridging Vein into the Transverse Sinus Provides a Reliable Measure for Preoperative Planning: An Anatomic Comparison between Cadavers and Neuroimages." Operative Neurosurgery 62, suppl_5 (May 1, 2008): ONS289—ONS296. http://dx.doi.org/10.1227/01.neu.0000326009.46197.ab.
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Abstract Objective: Understanding the anatomy of the transverse sinus and its associated bridging veins (BVs) is essential to approaching the posterior and middle incisural space. The venous phase of neuroimages has received increasing attention in preoperative planning. The aims of this study are to identify anatomic features of the dural entrance of the BVs into the transverse sinus on the cadaver and to correlate such features with those of digital subtraction angiography (DSA), computed tomographic venography (CTV), and magnetic resonance venography (MRV). Methods: A total of 30 adult cadavers and 76 patients were examined through anatomic dissection and DSA, CTV, and MRV, respectively. The number, diameter, and location of the BVs entering the sinus were measured, and comparisons were made between the cadavers and neuroimages. Results: We found that the way BVs entered the transverse sinus varied but was identifiable in DSA, CTV, and MRV images. Compared with the cadavers, DSA, CTV, and MRV revealed less than 50% of the BV entering the sinus because the smaller BVs were not seen on the neuroimages. However, the distribution pattern of the dural entrance of the BVs into the transverse sinus was relatively consistent between cadavers and neuroimages. Conclusion: Unique anatomic features of the dural entrance of a BV into the transverse sinus in the cadaver correspond to those evident in neuroimages; thus, identification of the dural entrance of the BVs with neuroimaging modalities provides a reliable measure for preoperative planning.
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Fang, Zheng-Hua. "Applications of the modified Rydberg–Vinet equation-of-state to the lower mantle and core." Modern Physics Letters B 30, no. 04 (February 10, 2016): 1650015. http://dx.doi.org/10.1142/s0217984916500159.
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A modified Rydberg–Vinet equation-of-state (mRV EOS) with an arbitrary nonzero-pressure reference point, as is derived strictly from the related Rydberg potential, has been applied to the mantle and the core. The tests and comparisons demonstrate that mRV EOS is superior to the reciprocal [Formula: see text]-primed equation [see F. D. Stacey and P. M. Davis, Phys. Earth Planet. Inter. 142 (2004) 137] not only because of its higher fitting accuracy but also because it has fewer fitting parameters and is easier to use.
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Yang, Joseph Yuan-Mou, Richard Beare, Marc L. Seal, A. Simon Harvey, Vicki A. Anderson, and Wirginia J. Maixner. "A systematic evaluation of intraoperative white matter tract shift in pediatric epilepsy surgery using high-field MRI and probabilistic high angular resolution diffusion imaging tractography." Journal of Neurosurgery: Pediatrics 19, no. 5 (May 2017): 592–605. http://dx.doi.org/10.3171/2016.11.peds16312.
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OBJECTIVECharacterization of intraoperative white matter tract (WMT) shift has the potential to compensate for neuronavigation inaccuracies using preoperative brain imaging. This study aimed to quantify and characterize intraoperative WMT shift from the global hemispheric to the regional tract-based scale and to investigate the impact of intraoperative factors (IOFs).METHODSHigh angular resolution diffusion imaging (HARDI) diffusion-weighted data were acquired over 5 consecutive perioperative time points (MR1 to MR5) in 16 epilepsy patients (8 male; mean age 9.8 years, range 3.8–15.8 years) using diagnostic and intraoperative 3-T MRI scanners. MR1 was the preoperative planning scan. MR2 was the first intraoperative scan acquired with the patient's head fixed in the surgical position. MR3 was the second intraoperative scan acquired following craniotomy and durotomy, prior to lesion resection. MR4 was the last intraoperative scan acquired following lesion resection, prior to wound closure. MR5 was a postoperative scan acquired at the 3-month follow-up visit. Ten association WMT/WMT segments and 1 projection WMT were generated via a probabilistic tractography algorithm from each MRI scan. Image registration was performed through pairwise MRI alignments using the skull segmentation. The MR1 and MR2 pairing represented the first surgical stage. The MR2 and MR3 pairing represented the second surgical stage. The MR3 and MR4 (or MR5) pairing represented the third surgical stage. The WMT shift was quantified by measuring displacements between a pair of WMT centerlines. Linear mixed-effects regression analyses were carried out for 6 IOFs: head rotation, craniotomy size, durotomy size, resected lesion volume, presence of brain edema, and CSF loss via ventricular penetration.RESULTSThe average WMT shift in the operative hemisphere was 2.37 mm (range 1.92–3.03 mm) during the first surgical stage, 2.19 mm (range 1.90–3.65 mm) during the second surgical stage, and 2.92 mm (range 2.19–4.32 mm) during the third surgical stage. Greater WMT shift occurred in the operative than the nonoperative hemisphere, in the WMTs adjacent to the surgical lesion rather than those remote to it, and in the superficial rather than the deep segment of the pyramidal tract. Durotomy size and resection size were significant, independent IOFs affecting WMT shift. The presence of brain edema was a marginally significant IOF. Craniotomy size, degree of head rotation, and ventricular penetration were not significant IOFs affecting WMT shift.CONCLUSIONSWMT shift occurs noticeably in tracts adjacent to the surgical lesions, and those motor tracts superficially placed in the operative hemisphere. Intraoperative probabilistic HARDI tractography following craniotomy, durotomy, and lesion resection may compensate for intraoperative WMT shift and improve neuronavigation accuracy.
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Zhang, Yaolin, Hui Wan, and Shu Yin Zhang. "Characterization of sugar maple wood-polymer composites: Monomer retention and polymer retention." Holzforschung 59, no. 3 (May 1, 2005): 322–29. http://dx.doi.org/10.1515/hf.2005.053.
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Abstract In this study, sugar maple samples were impregnated with three impregnants by a vacuum and pressure process and in situ polymerized by a catalyst-thermal procedure. The effects of polymeric monomers and their combinations on monomer retention by volume (MRV) and weight (MRW) and polymer retention (PR) were analyzed and the wood was examined by scanning electronic microscopy (SEM). The three methacrylates chosen as impregnants were methyl methacrylate (MMA), hydroxyethylene methacrylate (HEMA) and ethylene glycol dimethacrylate (EGDMA). The formulation combinations were determined by a mixture design. MRV was similar, regardless of formulation combinations, which indicated that these methacrylates show similar permeability into sugar maple. However, MRW was different between formulation combinations due to differences in monomer density. MRV was inversely related to wood density. PR was related to the combination of impregnants and inversely related to wood density. The impregnants resided in the vessel and the lumen. The morphology of polymers in the wood was different for different treatments due to the distinct molecular structures formed from each polymer.
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Winkler, Olivia, Waleed Brinjikji, Heinrich Lanfermann, Friedhelm Brassel, and Dan Meila. "Anatomy of the deep venous system in vein of Galen malformation and its changes after endovascular treatment depicted by magnetic resonance venography." Journal of NeuroInterventional Surgery 11, no. 1 (May 24, 2018): 84–89. http://dx.doi.org/10.1136/neurintsurg-2018-013789.
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Background and purposeIt is classically thought that the internal cerebral veins (ICV) do not communicate with the venous pouch of vein of Galen malformations (VGM). We report on the anatomy of the deep venous system in VGM with special emphasis on the drainage of the ICV and possible changes after endovascular treatment.Materials and methodsWe retrospectively analyzed DSA and 2D time-of-flight MR venograms of 55 children with VGM. We evaluated all pre- and post-operative images for the presence of the ICVs and determined their route of venous drainage.ResultsOf 55 children, pre-operative 2D MRV detected the ICVs in 19 cases (35%) compared with one case (2%) for pre-embolization DSA (2%) (P<0.0001). Of the cases in which the ICVs were seen preoperatively, in 15 cases (78.9%) the ICV drained directly into the VGM while in the other four cases, the ICV used alternative venous drainage routes. On post-operative MRV, the ICVs were seen in 17 cases (31%) on MRV and 10 cases (18.2%) on DSA with drainage into an adult-like vein of Galen in 13 cases (76%), respectively (P=0.08). In four cases normal ICV drainage into the vein of Galen was seen even when the venous sac was closed. In two cases there was a change in ICV drainage from the vein of Galen to the lateral mesencephalic vein.ConclusionThe communication of the ICV with the VGM is a common phenomenon. Different changes of venous drainage routes do occur after treatment and are best seen on MRV.
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Rodger, Marc, Leonard Avruch, Andre Olivier, and Mark Walker. "High Incidence of Pelvic Deep Vein Thrombosis Detected by Magnetic Resonance Venograpy Post-Caesarean Section." Blood 104, no. 11 (November 16, 2004): 2600. http://dx.doi.org/10.1182/blood.v104.11.2600.2600.
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Abstract Background Venous thromboembolism (VTE) is the leading cause of maternal mortality in the developed world. The post-partum period is the highest risk period for pregnancy associated VTE and delivery by Caesarean section further increases this risk. The true incidence of deep vein thrombosis (DVT) post- Caesarean section is unknown but felt to be low. The limited number of screening studies conducted to date have not included systematic pelvic vein imaging. Objectives To determine the incidence of DVT post-Caesarean section using Magnetic Resonance Venograpy (MRV) and bilateral compression ultrasounds. Methods Prospective cohort study of moderate to high risk women (one or more VTE risk factors) post-Caesarean section. On the day of post-partum discharge we conducted systematic bilateral proximal leg vein compression ultrasound imaging to detect proximal leg DVT and pelvic vein imaging with magnetic resonance venography (MRV). MRVs were independently and blindly interpreted by two radiologists with disagreements resolved by consensus. MRVs were interpreted as demonstrating definite, probable, possible or no thrombosis. Two rater Kappa scores were calculated from initial interpretations (prior to consensus review). Incidence of DVT and 95% confidence interval were calculated. Results Fifteen patients were recruited. At discharge, there were no proximal DVTs on bilateral leg compression ultrasounds. MRV results are shown in Table I. Conclusions The incidence of pelvic vein DVT post- Caesarean section is much higher than anticipated (46%). The clinical significance of this finding remains to be determined. However, diagnoses such as septic pelvic vein thrombophlebitis, which depend on demonstrating the presence pelvic vein thrombosis in the setting of post-partum fever may be falsely overdiagnosed. Pelvic vein thrombosis may be a common (and normal) finding post-Caesarean section. MRV may also prove to be a useful surrogate outcome measure in post-partum VTE prophylaxis studies. Table I: Pelvic Vein Imaging Results Post-C-Section MRV Consensus Result n/N (%) 95% CI Two Rater Kappa 95% CI= 95% Confidence Interval Definite Thrombosis 7/15 (46%) 21–73% 0.5 Definite or Probable Thrombosis 8/15 (53%) 27–79% 0.6 Definite, Probable or Possible Thrombosis 10/15 (66%) 38–88% 1.0 No Thrombosis 5/15 (33%) 12–62% 1.0
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Harada, Tomohiro. "ClassNK’s Activities to Comply with EU MRV." Marine Engineering 53, no. 5 (September 1, 2018): 631–34. http://dx.doi.org/10.5988/jime.53.631.
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