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1
Lovecká, Petra, Alžběta Svobodová, Anna Macůrková, Blanka Vrchotová, Kateřina Demnerová, and Zdeněk Wimmer. "Decorative Magnolia Plants: A Comparison of the Content of Their Biologically Active Components Showing Antimicrobial Effects." Plants 9, no. 7 (2020): 879. http://dx.doi.org/10.3390/plants9070879.
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Magnolia plants are used both as food supplements and as cosmetic and medicinal products. The objectives of this work consisted of preparing extracts from leaves and flowers of eight Magnolia plants, and of determining concentrations of magnolol (1 to 100 mg·g−1), honokiol (0.11 to 250 mg·g−1), and obovatol (0.09 to 650 mg·g−1), typical neolignans for the genus Magnolia, in extracts made by using a methanol/water (80/20) mixture. The tested Magnolia plants, over sixty years old, were obtained from Průhonický Park (Prague area, Czech Republic): M. tripetala MTR 1531, M. obovata MOB 1511, and six hybrid plants Magnolia × pruhoniciana, results of a crossbreeding of M. tripetala MTR 1531 with M. obovata MOB 1511. The identification of neolignans was performed by HRMS after a reversed-phase high-performance liquid chromatography (RP-HPLC) fractionation of an extract from M. tripetala MTR 1531. The highest concentrations of neolignans were found in the flowers, most often in their reproductive parts, and obovatol was the most abundant in every tested plant. The highest concentrations of neolignans were detected in parent plants, and lower concentrations in hybrid magnolias. Flower extracts from the parent plants M. tripetala MTR 1531 and M. obovata MOB 1511, flower extracts from the hybrid plants Magnolia × pruhoniciana MPR 0271, MPR 0151, and MPR 1531, and leaf extract from the hybrid plant Magnolia × pruhoniciana MPR 0271 inhibited growth of Staphylococcus aureus.
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Tahir, Muhammad, Aamer Ali Khattak, Erum Monis, and Sana Gul. "Association of MTR A2756G Gene Polymorphism with Risk of Head and Neck Cancer." Life and Science 1, no. 3 (2020): 6. http://dx.doi.org/10.37185/lns.1.1.82.
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 Objective: To perform genotyping for MTR A2756G polymorphism and identification of risk factors associated with head and neck squamous cell carcinoma (HNSCC). Study Design: Cross section, comparative study. Place and Duration of Study: The study was carried out at the Department of Biochemistry of Quaid-i- Azam University, Islamabad from October 2014 to August 2015. Materials and Methods: In this study, 292 diagnosed patients HNSCC and 324 normal individuals without any history of cancer were enrolled. Blood samples of patients and controls were collected in ethylenediamine tetra acetic acid (EDTA) and DNA was extracted using conventional method. All samples were genotyped for the MTR A2756G polymorphism using PCR-RFLP. Frequency of polymorphism was compared between HNSCC patients andcontrols. MultipleLogisticRegression(MLR)andchi-squaretestwasperformedtoexaminetheassociation of MTR A2756G polymorphism with risk factor. Results: Chi-square test of independence showed statistically significant difference among the variables of age, smoking and MTR A2756G genotype (p-value<0.05). Multivariate analysis showed that smoking (adjusted OR, 3.7; 95% CI, 2.3 – 6.0), age groups 41 – 50 years (adjusted OR, 3.6; 95% CI, .9 – 6.7) and > 60 years (adjusted OR, 3.5; 95% CI, 1.7 – 7.3), MTR 2756 AG genotype (adjusted OR, 2.1; 95% CI, 1.3 – 3.5) is associated with increased risk of HNSCC. Conclusion: The results suggest that the genetic polymorphism MTR A2756G is associated with the occurrence of HNSCC in the Pakistani population while the individuals between 40 to 50 years of age and those who are smokers are at a greater risk of developing HNSCC.
 
 
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Quinsten, Anton S., and Dominik Heße. "Auswirkung von Künstlicher Intelligenz auf den Beruf der MTR." Radiopraxis 17, no. 02 (2024): 63–71. http://dx.doi.org/10.1055/a-2197-3616.
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Dieser Artikel befasst sich mit den Auswirkungen der Künstlichen Intelligenz (KI) auf den Beruf der Medizinischen Technologinnen und Technologen für Radiologie (MTR). Die KI könnte entlang des Patientenbehandlungspfades in sämtlichen Bereichen der Radiologie MTR unterstützen und entlasten. Durch KI könnte sich der MTR-Beruf in Tätigkeitsbereiche unterteilen, die sich in patientennahe und patientenferne Tätigkeiten gliedern. In Zukunft könnten MTR, die Expertise im Bereich von KI besitzen, supervisorische Tätigkeiten ausführen, während MTR, die sich nicht mit KI beschäftigen, patientennahe Tätigkeiten wie die Betreuung und Lagerung von Patienten durchführen. Es ist absehbar, dass KI in naher Zukunft einige Aufgaben der MTR übernehmen wird und in ferner Zukunft autonom Untersuchungen durchführen wird. Um den Beruf des MTR zukunftsfähig zu gestalten, sollten MTR eine Strategie entwickeln und aktiv an der Entwicklung mitwirken.
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Torkkeli, Tommi, Markus Rautiainen, and Juhani Nuutinen. "Ciliary Ultrastructure and Mucociliary Transport in Upper Respiratory Tract Infections." American Journal of Rhinology 8, no. 5 (1994): 211–16. http://dx.doi.org/10.2500/105065894782537307.
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The ciliary ultrastructure in transmission electron microscopy and nasal mucociliary transport rate (MTR) by a radioisotopic method were studied in 50 patients with longstanding upper respiratory tract infections. The clinical symptoms correlated well with MTR. The symptoms in patients with MTR 3 mm/min or better were mild, but the patients with poor MTR (less than 3 mm/min) suffered from recurrent or severe infections. The completely normal ultrastructural findings were found only in patients with MTR better than 3 mm/min. All the patients with poor MTR had pathological ciliary ultrastructure, with numerous tubular anomalies and disorientation of ciliary beat direction. The outer dynein arms were found to be short in 16% of cases with poor MTR.
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Cloney, Michael Brendan, Andy C. Smith, Kenneth Weber, et al. "356 Quantitative Magnetization Transfer MRI Measurements of the Anterior Spinal Cord Region are Associated with Clinical Outcomes in Cervical Spondylotic Myelopathy." Neurosurgery 64, CN_suppl_1 (2017): 281–82. http://dx.doi.org/10.1093/neuros/nyx417.356.
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Abstract INTRODUCTION Magnetization transfer ratio (MTR) is a quantitative measure that correlates with myelin loss and neural tissue destruction in a variety of neurological diseases. For example, in patients with multiple sclerosis, MTR of white matter lesions may predict clinical disability. However, the usefulness of MTR in patients with cervical spondylotic myelopathy (CSM) has not been examined. METHODS We prospectively enrolled seven CSM patients and seven age-matched controls to undergo MRI imaging of the cervical spine. Nurick, Neck Disability Index (NDI), and modified Japanese Orthopedic Association (mJOA) scores were collected for all patients. Clinical hyperreflexia was tested at the MCP joint, using a 6-axis load cell. Reflex was simulated by quickly moving the joint from maximum flexion to maximum extension (300 °/sec). Anterior, lateral, and posterior cord MTR measurements were compared to clinical outcomes. RESULTS >Compared to controls, CSM patients had lower anterior cord MTR (38.29 v. 29.97, ? = −8.314, P = 0.0022), and equivalent posterior cord (P = 0.2896) and lateral cord (P = 0.3062) MTR. Higher Nurick scores were associated with lower anterior cord MTR (P = 0.0205), but not lateral cord (P = 0.5446) or posterior cord MTR (P = 0.1222). Lower mJOA was associated with lower anterior cord MTR (P = 0.0090), but not lateral cord (P = 0.4864) or posterior cord MTR (P = 0.4819). There was no association between NDI and MTR of the anterior (P = 0.4351), lateral (P = 0.7557), or posterior cord (P = 0.9171). There was a linear relationship between hyperreflexia and anterior cord MTR (slope = −117.3, R = 0.6598, P = 0.0379), but not lateral cord (P = 0.1906, R = 0.4511) or posterior cord (P = 0.2577, R = 0.3957) MTR. CONCLUSION Anterior cord MTR correlates with clinical outcomes as measured by mJOA index, Nurick score, and quantitative hyperreflexia. Anterior cord MTR is associated with clinically relevant hyperreflexia, and could play a role in the preoperative assessment of CSM. Understanding this radiological metric may refine surgical decision-making.
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Al-Namshah, K. S., and R. M. Mohamed. "Facile Synthesis of Mesoporous Ag Doped Titania Nanocomposite as Extraordinarily Effective Photo-Catalyst Beneath Vis Light." Nanoscience and Nanotechnology Letters 12, no. 3 (2020): 296–305. http://dx.doi.org/10.1166/nnl.2020.3125.
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In this probe, mesoporous titania nanorods (MTR) were fabricated as a photo-catalyst beneath Vis light illumination. The photo-catalytic enactment of the MTR nanocomposite boosted via decoration with metallic Ag. Role of Ag in boosting various aspects (optoelectronic, optical, surface, structural and photo-catalytic performance) of fabricated Ag@MTR nanocomposite was also affirmed. Ag@MTR nanocomposite accommodating 3.0% wt. Ag possessed lower band gap (2.17 eV) compared to that of pure MTR nanocomposite (3.25 eV), and so the Ag-doped nanocomposite acquired upgraded Vis light absorption aspects. The photo-catalytic performance for the Ag doped MTR nanocomposite was tested via its capability to remediate ciprofloxacin (CIP) antibiotic from aquatic medium. 1 h was enough for complete (100%) degradation of ciprofloxacin (CIP) via utilization of 2.4 g · L–1 Ag@MTR nanocomposite accommodating 3.0% wt. Ag. The boosted photo-catalytic efficacy of fabricated Ag@MTR nanocomposite was attributed to the enlarged charge carrier's separation beside the diminished electron–hole reconsolidation, as a result of surface plasmon resonance of Ag@MTR nanocomposite. In addition, the fabricated Ag@MTR nanocomposite exhibited great stability with distinguished recyclability after application up to five cycles. This investigation recommends the operation of Ag doped titania photo-catalyst for efficient remediation of pharmaceutical pollutants from aquatic environment.
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Ernantika, Devi, Luhur Prasetiyo, and Royyan Ramdhani Djayusman. "TEACHINGS OF THE MASYARAKAT TANPA RIBA IN THE LIGHT OF THE SOCIOLOGY OF KNOWLEDGE." Muslim Heritage 7, no. 2 (2022): 306–21. http://dx.doi.org/10.21154/muslimheritage.v7i2.3916.
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AbstractThe purpose of this study is to explore the attitude background of the Society Without Usury (herein after written MTR). The MTR rejects the existence of interest and banks. MTR is a community committed to developing a business without usury, without debt, and without contracts that are not under sharia. One form of this commitment is that MTR members refuse to pay bank debts and interest. Meanwhile, the banks believe that the customer should pay the debt and interest according to the contract. This research is qualitative. Data were obtained through in-depth interviews, observations, and documentation. Key informants are administrators and members of the MTR. Based on the results of the study, it can be concluded that the MTR community has three qualification meanings in the sociology of knowledge, namely objective meaning, which can be seen from community understanding and community beliefs regarding usury, especially bank interest. The behavior of MTR residents is formed due to external factors, namely the stimulus from the family environment that has previously joined the MTR community. The expressive meaning of the MTR community is the meaning impregnated by every MTR citizen who is integrated with the behavior of avoiding usury and doing other teachings, such as improving the creed, improving relations with the social environment, still seeking knowledge, especially the science of good peace, and others. Meanwhile, the documentary meaning is a material activity manifested in religious practices and rituals. AbstrakTujuan dari penelitian ini adalah untuk mendalami latar belakang sikap kelompok Masyarakat Tanpa Riba (selanjutnya ditulis MTR) yang menolak keberadaan bunga dan bank. MTR adalah sebuah komunitas yang mempunyai komitmen mengembangkan bisnis tanpa riba, tanpa utang, tanpa akad-akad yang tidak sesuai syariah. Salah satu bentuk komitmen tersebut adalah anggota MTR menolak untuk membayar hutang bank beserta bunganya. Sedangkan pihak bank berpandangan bahwa nasabah memiliki kewajiban untuk membayar hutang beserta bunganya sesuai kesepakatan kontrak di awal. Penelitian ini bersifat kualitatif. Data diperoleh melalui wawancara mendalam, observasi, dan dokumentasi. Informan kunci adalah pengurus dan anggota MTR. Berdasarkan hasil penelitian dapat disimpulkan bahwa komunitas MTR memiliki tiga makna kualifikasi dalam sosiologi pengetahuan, yakni makna objektif yang dapat dilihat dari pemahaman komunitas dan keyakinan komunitas mengenai riba terutama bunga bank. Perilaku warga MTR terbentuk karena faktor eksternal, yakni stimulus dari lingkungan keluarga yang sudah terlebih dahulu bergabung dengan komunitas MTR. Makna ekspresif dari komunita MTR adalah makna yang diresapi oleh setiap warga MTR yang terintegrasi dalam perilaku menghindari riba dan melakukan ajaran lainnya, seperti memperbaiki akidah, memperbaiki hubungan dengan lingkungan sosial, tetap mencari ilmu terutama ilmu bermuamalah yang baik, dan lain-lainnya. Sementara, makna dokumenter, yakni sebagai kegiatan material yang terwujud dalam bentuk praktik agama dan ritualnya.
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Trip, SA, PG Schlottmann, SJ Jones, et al. "Optic nerve magnetization transfer imaging and measures of axonal loss and demyelination in optic neuritis." Multiple Sclerosis Journal 13, no. 7 (2007): 875–79. http://dx.doi.org/10.1177/1352458507076952.
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Magnetization transfer imaging is an MRI technique that provides quantitative information about in vivo tissue integrity, including myelin and axonal content, and is expressed as the magnetization transfer ratio (MTR). The optic neuritis lesion can model the MS lesion in vivo and permits use of non-invasive markers of optic nerve myelination (visual evoked potential [VEP] latency) and retinal neuroaxonal loss (optical coherence tomography [OCT]) to provide further information about the in vivo substrates of optic nerve MTR. Twenty-five patients with optic neuritis were studied using an optic nerve MTR sequence, quantitative visual function testing, VEPs and OCT, along with 15 controls. MTR was reduced in affected nerves compared to both clinically unaffected nerves from patients and control nerves ( P < 0.001). Whole-nerve MTR correlated modestly with central-field VEP latency but more strongly when lesion-only MTR was measured, when a modest correlation with whole-field VEP latency emerged. OCT-quantified retinal neuroaxonal loss also correlated with MTR. In conclusion, markers of optic nerve myelination and axonal loss both correlate with optic nerve MTR. Because axonal loss following optic neuritis also results in myelin loss, the relative contributions of the two pathological conditions to the MTR measures cannot be estimated from this study. Multiple Sclerosis 2007; 13: 875—879. http://msj.sagepub.com
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Campero, Alvaro, Pablo Ajler, Carlos Rica, and Albert Rhoton. "Cavernomas and Arteriovenous Malformations in the Mesial Temporal Region: Microsurgical Anatomy and Approaches." Operative Neurosurgery 13, no. 1 (2016): 113–23. http://dx.doi.org/10.1227/neu.0000000000001239.
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Abstract BACKGROUND: The mesial temporal region (MTR) is located deep in the temporal lobe and it is surrounded by important vascular and nervous structures that should be preserved during surgery. OBJECTIVE: To describe microsurgical anatomy and approaches to the MTR in relation to cavernomas and arteriovenous malformations (AVMs). METHODS: Five formalin-fixed and red silicone-embedded heads of adult cadavers were used for this study. Between January 2003 and June 2014, 7 patients with cavernomas and 6 patients with AVMs in the MTR underwent surgery. RESULTS: The MTR of the cadavers was divided into 3 areas: anterior, middle, and posterior. Of the 7 patients with MTR cavernomas, 4 were located anteriorly, 2 were located medially, and 1 was located posteriorly. Of the 6 patients with MTR AVMs, 3 were located in the anterior sector, 2 in the middle sector, and 1 in the posterior sector. For the anterior portion of the MTR, a transsylvian-transinsular approach was used; for the middle portion of the MTR, a transtemporal approach was used (anterior temporal lobectomy); and for the posterior portion of the MTR, a supracerebellar-transtentorial approach was used. CONCLUSION: Dividing the MTR into 3 regions allows us to adapt the approach to lesion location. Thus, the anterior sector can be approached via the sylvian fissure, the middle sector can be approached transtemporally, and the posterior sector can be approached via the supracerebellar approach.
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Németh, Gábor Árpád, and Máté István Lugosi. "MTR Model-Based Testing Framework MTR Model-Based Testing Framework MTR Model-Based Testing Framework." Infocommunications journal 16, no. 2 (2024): 11–18. http://dx.doi.org/10.36244/icj.2024.2.2.
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In this article we propose a novel, free and open- source model-based testing framework for finite state machine specifications. The various model handling and test generation options make the framework suitable for testing complex systems and provide a solid background for investigating different automated test design methodologies. The complexity and fault detection capabilities of the available algorithms are investigated through analytical analyses and simulations applying randomly injected faults.
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Hughes, Jeffrey A. "In vivo hydrolysis ofS-adenosyl-L-methionine inEscherichia coliincreases export of 5-methylthioribose." Canadian Journal of Microbiology 52, no. 6 (2006): 599–602. http://dx.doi.org/10.1139/w06-008.
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Escherichia coli can not synthesize methionine from 5-methylthioribose (MTR) but instead exports this sulfur-containing, energy-rich molecule into the surrounding medium. Transforming E. coli with plasmids that direct expression of the cloned coliphage T3 S-adenosyl-L-methionine (SAM) hydrolase (SAMase) induces the met regulon by cleaving the SAM co-repressor to form 5′-methylthioadenosine, which is then cleaved to produce MTR. To test the effect of in vivo SAMase activity on MTR production and its fate, cultures were incubated in the presence of [35S]methionine and [methyl-3H]methionine. Cells with SAMase activity produced significantly enhanced levels (up to 40-fold in some trials) of extracellular MTR — the only radiolabeled compound released in significant amounts — when compared with controls. SAM synthetase (metK) mutants transformed with SAMase expression vectors did not show this increase, verifying the path through SAM as the sole route to MTR production. SAMase expression had little or no effect on intracellular MTR pools, levels of radiolabeled macromolecules, or the transfer of methyl groups to compounds that could be precipitated by trichloroacetic acid. Thus, MTR appears to be a dead-end metabolite in E. coli, begging questions about how this has evolved, the mechanism of MTR export for the cell, and whether the release of MTR is important for some other activity.Key words: 5-methylthioribose, S-adenosyl-L-methionine, SAMase, Escherichia coli, export.
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López, Karina, Radhouene Neji, Rahul K. Mukherjee, et al. "Contrast-free high-resolution 3D magnetization transfer imaging for simultaneous myocardial scar and cardiac vein visualization." Magnetic Resonance Materials in Physics, Biology and Medicine 33, no. 5 (2020): 627–40. http://dx.doi.org/10.1007/s10334-020-00833-9.
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Abstract Objective To develop a three-dimensional (3D) high-resolution free-breathing magnetization transfer ratio (MTR) sequence for contrast-free assessment of myocardial infarct and coronary vein anatomy. Materials and methods Two datasets with and without off-resonance magnetization transfer preparation were sequentially acquired to compute MTR. 2D image navigators enabled beat-to-beat translational and bin-to-bin non-rigid motion correction. Two different imaging sequences were explored. MTR scar localization was compared against 3D late gadolinium enhancement (LGE) in a porcine model of myocardial infarction. MTR variability across the left ventricle and vessel sharpness in the coronary veins were evaluated in healthy human subjects. Results A decrease in MTR was observed in areas with LGE in all pigs (non-infarct: 25.1 ± 1.7% vs infarct: 16.8 ± 1.9%). The average infarct volume overlap on MTR and LGE was 62.5 ± 19.2%. In humans, mean MTR in myocardium was between 37 and 40%. Spatial variability was between 15 and 20% of the mean value. 3D whole heart MT-prepared datasets enabled coronary vein visualization with up to 8% improved vessel sharpness for non-rigid compared to translational motion correction. Discussion MTR and LGE showed agreement in infarct detection and localization in a swine model. Free-breathing 3D MTR maps are feasible in humans but high spatial variability was observed. Further clinical studies are warranted.
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van den Elskamp, IJ, DL Knol, H. Vrenken, et al. "Lesional magnetization transfer ratio: a feasible outcome for remyelinating treatment trials in multiple sclerosis." Multiple Sclerosis Journal 16, no. 6 (2010): 660–69. http://dx.doi.org/10.1177/1352458510364630.
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Magnetization transfer ratio (MTR) is a sensitive parameter to quantify the integrity of myelinated white matter in patients with multiple sclerosis. Lesional MTR decreases in the acute phase due to demyelination, and subsequently shows recovery depending on the degree of remyelination in the absence of axonal loss. Recovery of average lesion MTR therefore might prove a viable outcome measure to assess the effect of remyelinating agents. Our objective was to determine the required sample size for phase II multicentre clinical trials using the recovery of average lesion MTR as primary outcome measure. With 7-monthly MRI scans, the MTR evolution of 349 new enhancing lesions before and after enhancement was assessed in 32 MS patients from 5 centres. Multilevel models were fitted to the data yielding estimates for the variance components, which were applied in power calculations. Sample sizes were determined for placebo-controlled, multicentre trials using lesional MTR recovery post-enhancement as primary outcome measure. Average lesion MTR decreased slightly in the build-up to enhancement, decreased dramatically during enhancement and showed recovery in the period after cessation. The power calculations showed that for a power of 80%, approximately 136 patients per trial (mean number of 6 lesions per patient) are required to detect a 30% increase in lesional MTR post-enhancement compared with placebo, whereas 48 subjects are required to detect a 50% increase in lesional MTR compared with placebo. Recovery of lesion MTR is a feasible outcome measure for future multicentre clinical trials measuring the effect of remyelinating agents.
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Acharjee, S., JL Do-Rego, DY Oh, et al. "Molecular cloning, pharmacological characterization, and histochemical distribution of frog vasotocin and mesotocin receptors." Journal of Molecular Endocrinology 33, no. 1 (2004): 293–313. http://dx.doi.org/10.1677/jme.0.0330293.
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The neurohypophysial nonapeptides vasotocin (VT) and mesotocin (MT) are the amphibian counterparts of arginine vasopressin (AVP) and oxytocin (OT). We have here reported the cloning and functional characterization of the receptors for vasotocin (VTR) and mesotocin (MTR) in two species of frog, Rana catesbeiana and Rana esculenta. The frog VTR and MTR cDNAs encode proteins of 419 and 384 amino acids respectively. Frog VTR exhibits a high degree of sequence identity with the mammalian AVP-1a (V1a) receptor while the frog MTR possesses a high degree of sequence identity with the mammalian OT receptor. Activation of VTR induced both c-fos promoter- and cAMP-responsive element (CRE)-driven transcriptional activities, while activation of MTR induced c-fos promoter-driven transcriptional activity but failed to evoke CRE-driven transcriptional activity, suggesting differential G protein coupling between VTR and MTR. The VTR exhibited the highest sensitivity for VT followed by OT>AVP approximately MT, whereas the MTR showed preferential ligand sensitivity for MT>OT>VT>AVP. A V1a agonist but not V2 and OT agonists substantially activated both VTR and MTR with a similar sensitivity. V1a, V2 and OT antagonists inhibited MT-induced MTR activation but not VT-induced VTR activation. In the frog brain, VTR and MTR mRNAs were found to be widely expressed in the telencephalon, diencephalon and mesencephalon, and exhibited very similar regional distribution. In the pituitary, VTR and MTR were expressed in the distal and intermediate lobes but were virtually absent in the neural lobe. Taken together, these data indicated that, although the distribution of VTR and MTR largely overlaps in the frog brain and pituitary, VT and MT may play distinct activities owing to the ligand selectivity and different signaling pathways activated by their receptors.
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Alam, Suhyla, Chengyu Li, Kathryn H. Bradburn, Kai Zhao, and Thomas S. Lee. "Impact of Middle Turbinectomy on Airflow to the Olfactory Cleft: A Computational Fluid Dynamics Study." American Journal of Rhinology & Allergy 33, no. 3 (2018): 263–68. http://dx.doi.org/10.1177/1945892418816841.
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Background The impact of middle turbinate resection (MTR) on olfaction remains a point of debate in the current literature. Few studies have objectively evaluated olfactory cleft airflow following MTR; thus, the mechanism by which MTR may impact olfaction is poorly understood. It is not known whether the postsurgical changes in airway volume, flow, and resistance increase odorant transport or disrupt the patterns of normal airflow. Computational fluid dynamics can be used to study the nasal airway and predict responses to surgical intervention. Objective To evaluate the functional impact of MTR on nasal airflow, resistance, and olfaction. Methods Five maxillofacial computed tomography scans of patients without signs of significant sinusitis or nasal polyposis were used. Control models for each patient were compared to their corresponding model after virtual total MTR. For each model, nasal airway volume, nasal resistance, and air flow rate were determined. Odorant transport of 3 different odorants in the nasal cavity was simulated based on the computed steady airflow field. Results Total airflow significantly increased following bilateral MTR in all patient models ( P < .05). Consistent with our airflow results, we found a decrease in nasal resistance following MTR. MTR significantly increased area averaged flux to the olfactory cleft when compared to controls for phenylethyl alcohol (high-sorptive odorant). Results for carvone (medium sorptive) were similarly elevated. MTR impact on limonene, a low flux odorant, was equivocal. Conclusion MTR increases nasal airflow while decreasing the nasal resistance. Overall, olfactory flux increased for high sorptive (phenylethyl alcohol) and medium sorpitve (l-carvone) odorants. However, the significant variation observed in one of our models suggests that the effects of MTR on the nasal airflow and the resultant olfaction can vary between individuals based on individual anatomic differences.
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Zhang, Chao, Yuan Lin, Zhihua Han, et al. "Feasibility of T2 Mapping and Magnetic Transfer Ratio for Diagnosis of Intervertebral Disc Degeneration at the Cervicothoracic Junction: A Pilot Study." BioMed Research International 2019 (May 2, 2019): 1–9. http://dx.doi.org/10.1155/2019/6396073.
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Background. Intervertebral disc degeneration (IDD) at the cervicothoracic junction of spine is clinically relevant, however, little attention had been paid. T2 mapping and magnetic transfer ratio (MTR) are useful magnetic resonance imaging (MRI) techniques to quantitatively evaluate IDD, revealing the biochemical changes within the intervertebral disc. To compare T2 mapping with MTR imaging regarding their accuracy to quantitatively diagnose intervertebral disc degeneration at the cervicothoracic junction, influences of anatomical level, gender, age, and Pfirrmann grade of T2 relaxation time values and MTR values were evaluated. Methods. Sixty-seven patients with neck and upper back pain were included and examined with both T2 mapping and MTR imaging. The Pfirrmann grade, T2 relaxation time values, and MTR value of each disc between C7 and T3 were measured. Differences were investigated among different segmental levels, genders, age ranges, and Pfirrmann grades. The diagnostic accuracy of both MRI techniques was compared using the receiver operating characteristic (ROC) curves. Results. No significant difference was detected comparing T2 relaxation time values or MTR values among different anatomical levels, genders, and segmental levels. And we generally found that T2 relaxation time values decreased, while MTR value increased with increasing age. Importantly, we demonstrated the significant correlation between either T2 relaxation time values or MTR value and Pfirrmann grade. Conclusion. We proved the better accuracy of T2 mapping over MTR imaging to quantitatively evaluate the intervertebral disc degeneration of the cervicothoracic junction.
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Samson, Rebecca S., Manuel J. Cardoso, Nils Muhlert, et al. "Investigation of outer cortical magnetisation transfer ratio abnormalities in multiple sclerosis clinical subgroups." Multiple Sclerosis Journal 20, no. 10 (2014): 1322–30. http://dx.doi.org/10.1177/1352458514522537.
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Background: Pathological abnormalities including demyelination and neuronal loss are reported in the outer cortex in multiple sclerosis (MS). Objective: We investigated for in vivo evidence of outer cortical abnormalities by measuring the magnetisation transfer ratio (MTR) in MS patients of different subgroups. Methods: Forty-four relapsing–remitting (RR) (mean age 41.9 years, median Expanded Disability Status Scale (EDSS) 2.0), 25 secondary progressive (SP) (54.1 years, EDSS 6.5) and 19 primary progressive (PP) (53.1 years, EDSS 6.0) MS patients and 35 healthy control subjects (mean age 39.2 years) were studied. Three-dimensional (3D) 1×1×1mm3 T1-weighted images and MTR data were acquired. The cortex was segmented, then subdivided into outer and inner bands, and MTR values were calculated for each band. Results: In a pairwise analysis, mean outer cortical MTR was lower than mean inner cortical MTR in all MS groups and controls ( p<0.001). Compared with controls, outer cortical MTR was decreased in SPMS ( p<0.001) and RRMS ( p<0.01), but not PPMS. Outer cortical MTR was lower in SPMS than PPMS ( p<0.01) and RRMS ( p<0.01). Conclusions: Lower outer than inner cortical MTR in healthy controls may reflect differences in myelin content. The lowest outer cortical MTR was seen in SPMS and is consistent with more extensive outer cortical (including subpial) pathology, such as demyelination and neuronal loss, as observed in post-mortem studies of SPMS patients.
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Wan, Gang, Jenny Yan, Yuhan Fei, Daniel J. Pagano, and Scott Kennedy. "A Conserved NRDE-2/MTR-4 Complex Mediates Nuclear RNAi in Caenorhabditis elegans." Genetics 216, no. 4 (2020): 1071–85. http://dx.doi.org/10.1534/genetics.120.303631.
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Small regulatory RNAs, such as small interfering RNAs (siRNAs) and PIWI-interacting RNAs, regulate splicing, transcription, and genome integrity in many eukaryotes. In Caenorhabditis elegans, siRNAs bind nuclear Argonautes (AGOs), which interact with homologous premessenger RNAs to recruit downstream silencing effectors, such as NRDE-2, to direct cotranscriptional gene silencing [or nuclear RNA interference (RNAi)]. To further our understanding of the mechanism of nuclear RNAi, we conducted immunoprecipitation-mass spectrometry on C. elegansNRDE-2. The major NRDE-2 interacting protein identified was the RNA helicase MTR-4. Co-immunoprecipitation analyses confirmed a physical association between NRDE-2 and MTR-4. MTR-4 colocalizes with NRDE-2 within the nuclei of most/all C. elegans somatic and germline cells. MTR-4 is required for nuclear RNAi, and interestingly, MTR-4 is recruited to premessenger RNAs undergoing nuclear RNAi via a process requiring nuclear siRNAs, the nuclear AGO HRDE-1, and NRDE-2, indicating that MTR-4 is a component of the C. elegans nuclear RNAi machinery. Finally, we confirm previous reports showing that human (Hs)NRDE2 and HsMTR4 also physically interact. Our data show that the NRDE-2/MTR-4 interactions are evolutionarily conserved, and that, in C. elegans, the NRDE-2/MTR-4 complex contributes to siRNA-directed cotranscriptional gene silencing.
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Davies, G. R., D. R. Altmann, W. Rashid, et al. "Emergence of thalamic magnetization transfer ratio abnormality in early relapsing—remitting multiple sclerosis." Multiple Sclerosis Journal 11, no. 3 (2005): 276–81. http://dx.doi.org/10.1191/1352458505ms1166oa.
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While there is now evidence for thalamic abnormality in established secondary progressive and relapsing—remitting multiple sclerosis (MS), it remains unclear when such abnormality begins. This study investigated the emergence of thalamic abnormality in relapsing—remitting MS by assessing the thalamic magnetization transfer ratio (MTR) in a cohort with clinically early disease. Twenty-three patients with early relapsing—remitting MS (mean age 37; mean disease duration 1.9 years; Expanded Disability Status Scale (EDSS) range 0-3) and 19 healthy controls (mean age 34) were imaged yearly with a magnetization transfer imaging sequence. Twenty-two MS patients and 14 controls completed two-year follow-up. Regions of interest were placed in both thalami and mean thalamic MTR calculated. At baseline, significant differences between patient and control thalamic MTR were not observed. However, at years one and two, the thalamic MTR in patients was significantly lower than control MTR. Although baseline lesion volume did not correlate with baseline thalamic MTR, at year one, an association between baseline lesion volume and year one thalamic MTR emerged. There was also a significant inverse correlation between EDSS and thalamic MTR (r= −0.47, P=0.02). The study suggests that thalamic involvement occurs within the first five years of MS onset, when most patients are still minimally disabled.
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Hanafi Majid, Syahid Anuar, and Noor Hafizah Hassan. "TPOT-MTR: A Multiple Target Regression Based on Genetic Algorithm of Automated Machine Learning Systems." Journal of Advanced Research in Applied Sciences and Engineering Technology 30, no. 3 (2023): 104–26. http://dx.doi.org/10.37934/araset.30.3.104126.
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The concept that a cross correlation might improve prediction error underpins machine learning algorithms for multi-target regression (MTR). Numerous MTR approaches have been created in recent years, however there are still uncertainties concerning how their performances are impacted by dataset properties such as linearity, number of targets, and cross correlational complexity. In order to contribute to a better understanding of the relationship between dataset properties and MTR methods, authors proposed a new model of TPOT-MTR, which its result will be compared to previously generated 33 synthetic datasets with controlled characteristics and tested their performance against other two MTR methods, Random Forest and SVM. The results demonstrated that TPOT-MTR approaches could enhance performance even in datasets with non-linearly correlated targets, although the prediction improvement varies depending on the method and regressor combinations used.
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Isabet, Baptiste, Maribel Pino, Manon Lewis, Samuel Benveniste, and Anne-Sophie Rigaud. "Social Telepresence Robots: A Narrative Review of Experiments Involving Older Adults before and during the COVID-19 Pandemic." International Journal of Environmental Research and Public Health 18, no. 7 (2021): 3597. http://dx.doi.org/10.3390/ijerph18073597.
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Social isolation is a common phenomenon among the elderly. Retirement, widowhood, and increased prevalence of chronic diseases in this age group lead to a decline in social relationships, which in turn has adverse consequences on health and well-being. The coronavirus COVID-19 crisis worsened this situation, raising interest for mobile telepresence robots (MTR) that would help create, maintain, and strengthen social relationships. MTR are tools equipped with a camera, monitor, microphone, and speaker, with a body on wheels that allows for remote-controlled and sometimes autonomous movement aiming to provide easy access to assistance and networking services. We conducted a narrative review of literature describing experimental studies of MTR involving elderly people over the last 20 years, including during the COVID-19 period. The aim of this review was to examine whether MTR use was beneficial for reducing loneliness and social isolation among older adults at home and in health and care institutions and to examine the current benefits and barriers to their use and implementation. We screened 1754 references and included 24 research papers focusing on the usability, acceptability, and effectiveness of MTR. News reports on MTR use during the COVID-19 period were also examined. A qualitative, multidimensional analysis methodology inspired by a health technology assessment model was used to identify facilitating and limiting factors and investigate if and how MTR could reduce social isolation in elderly people. Reviewed studies provide encouraging evidence that MTR have potential in this regard, as experiments report positive feedback on MTR design and core functionalities. However, our analysis also points to specific technical, ergonomic, and ethical challenges that remain to be solved, highlighting the need for further multidimensional research on the design and impact of MTR interventions for older adults and building on new insights gained during the COVID-19 pandemic.
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Cooper, Daniel B., Courtney J. Walker, and W. Jay Christian. "Maternal proximity to mountain-top removal mining and birth defects in Appalachian Kentucky, 1997–2003." PLOS ONE 17, no. 8 (2022): e0272998. http://dx.doi.org/10.1371/journal.pone.0272998.
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Extraction of coal through mountaintop removal mining (MTR) alters many dimensions of the landscape. Explosive blasts, exposed rock, and coal washing have the potential to pollute air and water. Previous research suggests that infants born to mothers living in areas with MTR have a higher prevalence of birth defects. In this cross-sectional study, we further examine the relationship between MTR activity and several types of birth defects. Maternal exposure to MTR was assessed using remote sensing data from Skytruth, which captures MTR activity in the Central Appalachian region of the United States. Active MTR area was quantified within a five-kilometer buffer surrounding geocoded maternal address captured on birth records for live births to Appalachian Kentucky mothers between 1997 and 2003 (N = 95,581). We assigned high, medium, and low exposure based on the tertile of total MTR area within 5-km, and births with no MTR within this buffer were assigned zero exposure. The presence or absence of a birth defect grouped into six major organ systems was identified using birth records alone. Finally, we applied conditional multiple imputation for variables with missing values before conducting separate multivariable log-binomial regression models for each birth defect group. Prevalence ratio (PR) estimates were adjusted for individual level covariates from birth records. The prevalence of gastro-intestinal defects was significantly higher in birth records with high and low active MTR exposure compared to records with no exposure. (High exposure: PR = 1.99, 95% CI = 1.14–3.47; low exposure PR = 1.88, 95% CI = 1.06–3.31). This study supports some of the existing findings of previous ecological studies. Research addressing the relationship between gastro-intestinal birth defects and MTR coal mining is warranted but should carefully consider temporal dimensions of exposure.
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Vrenken, H., P. J. W. Pouwels, S. Ropele, et al. "Magnetization transfer ratio measurement in multiple sclerosis normal-appearing brain tissue: limited differences with controls but relationships with clinical and MR measures of disease." Multiple Sclerosis Journal 13, no. 6 (2007): 708–16. http://dx.doi.org/10.1177/1352458506075521.
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We investigated the magnetization transfer ratio (MTR) of normal-appearing white (NAWM) and grey matter (NAGM) in a relatively large group of multiple sclerosis (MS) patients, and the relations of MTR changes with clinical disability. MTR was measured in 66 MS patients (12 PP, 35 RR, 19 SP) and 23 healthy controls, using a whole-brain 3D-FLASH technique corrected post-hoc for B1-induced variation. Histogram parameters of conservatively selected NAWM and cortical NAGM were analysed using Bonferroni-corrected ANOVA with age as covariate. Additionally, manually outlined regions of interest were analysed using a multilevel method. Lesions had low MTR (mean 22.7±6.9%), but NAWM exhibited limited changes: MTR histogram peak position was 32.8±1.0% in controls and 32.4±0.9% in MS patients, with a significant decrease compared to controls only in SPMS patients (31.9±1.1%, p=0.045). Cortical NAGM histograms did not differ significantly between patients and controls. In SPMS, regional mean MTR was significantly decreased in corpus callosum and hippocampus. MTR histogram parameters of NAGM and NAWM were correlated with EDSS and MSFC scores, with lesion volume and with normalized brain volume. We conclude that disease-induced MTR changes were small in MS NAWM and NAGM, but did correlate with clinical decline, lesion volume and overall cerebral atrophy. Multiple Sclerosis 2007; 13: 708-716. http://msj.sagepub.com
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Furby, J., T. Hayton, D. Altmann, et al. "Different white matter lesion characteristics correlate with distinct grey matter abnormalities on magnetic resonance imaging in secondary progressive multiple sclerosis." Multiple Sclerosis Journal 15, no. 6 (2009): 687–94. http://dx.doi.org/10.1177/1352458509103176.
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Background Although MRI measures of grey matter abnormality correlate with clinical disability in multiple sclerosis, it is uncertain whether grey matter abnormality measured on MRI is entirely due to a primary grey matter process or whether it is partly related to disease in the white matter. Methods To explore potential mechanisms of grey matter damage we assessed the relationship of white matter T2 lesion volume, T1 lesion volume, and mean lesion magnetisation transfer ratio (MTR), with MRI measures of tissue atrophy and MTR in the grey matter in 117 subjects with secondary progressive multiple sclerosis. Results Grey matter fraction and mean grey matter MTR were strongly associated with lesion volumes and lesion MTR mean ( r = ±0.63–0.72). In contrast, only weak to moderate correlations existed between white matter and lesion measures. In a stepwise regression model, T1 lesion volume was the only independent lesion correlate of grey matter fraction and accounted for 52% of the variance. Lesion MTR mean and T2 lesion volume were independent correlates of mean grey matter MTR, accounting for 57% of the variance. Conclusions Axonal transection within lesions with secondary degeneration into the grey matter may explain the relationship between T1 lesions and grey matter fraction. A parallel accumulation of demyelinating lesions in white and grey matter may contribute to the association of T2 lesion volume and lesion MTR with grey matter MTR.
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Shariff, Jaffer A., and Athanasios I. Zavras. "Malignant Transformation Rate in Patients Presenting Oral Epithelial Dysplasia: Systematic Review and Meta-Analysis." Journal of Oral Diseases 2015 (November 4, 2015): 1–10. http://dx.doi.org/10.1155/2015/854636.
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Objective. To perform a systematic review and meta-analysis on studies that assess malignant transformation rates (MTR) of oral epithelial dysplasia. Materials and Methods. This review was planned and conducted in accordance with the meta-analysis of observational studies in epidemiology (MOOSE) guidelines. PubMed, EMBASE, Google Scholar, and Cochrane databases were screened to identify observational studies. Quality assessments were completed by two reviewers independently using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Pooled-malignant transformation rate (MTR) in person years, subgroup, sensitivity, and publication bias analysis were calculated using STATA 13.0 and Comprehensive Meta-Analysis software. Results. Sixteen observational cohort studies were identified with a total of 3708 participants from Asia, North America, and Europe. Analysis showed a MTR of 10.5% (pooled-MTR: 10.5, 95% CI: 3.7 to 17.3; fixed effect model, I2=0.0%; Q-value = 2.389; p>0.05) among patients with histologically confirmed oral epithelia dysplasia undergoing long-term follow-up. Higher MTR in person year were seen among the sever dysplastic cases (pooled-MTR: 14.4%, 95% CI: 5.3% to 23.5%), studies published in Europe (pooled-MTR: 12.6%, 95% CI: 8.0% to 24.3%), and retrospective studies (pooled-MTR: 11.0%, 95% CI: 2.2% to 19.9%). Conclusion. These studies show that oral epithelial dysplasia has a significant high rate of transformation to cancer.
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Silk, Michael, Slavé Petrovski, and David B. Ascher. "MTR-Viewer: identifying regions within genes under purifying selection." Nucleic Acids Research 47, W1 (2019): W121—W126. http://dx.doi.org/10.1093/nar/gkz457.
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Abstract Advances in genomic sequencing have enormous potential to revolutionize personalized medicine, however distinguishing disease-causing from benign variants remains a challenge. The increasing number of human genome and exome sequences available has revealed areas where unfavourable variation is removed through purifying selection. Here, we present the MTR-Viewer, a web-server enabling easy visualization at the gene or variant level of the Missense Tolerance Ratio (MTR), a measure of regional intolerance to missense variation calculated using variation from 240 000 exome and genome sequences. The MTR-Viewer enables exploration of MTR calculations, using different sliding windows, for over 18 000 human protein-coding genes and 85 000 alternative transcripts. Users can also view MTR scores calculated for specific ethnicities, to enable easy exploration of regions that may be under different selective pressure. The spatial distribution of population and known disease variants is also displayed on the protein's domain structure. Intolerant regions were found to be highly enriched for ClinVar pathogenic and COSMIC somatic missense variants (Mann–Whitney U test P < 2.2 × 10−16). As the MTR is not biased by known domains and protein features, it can highlight functionally important regions within genes overlooked or inaccessible by traditional methods. MTR-Viewer is freely available via a user friendly web-server at http://biosig.unimelb.edu.au/mtr-viewer/.
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Al-Hakim, Sofian, Doli Witro, and Muhamad Izazi Nurjaman. "Law of Usury (RIBA) According to Masyarakat Tanpa Riba (MTR): Perceptions, Attitudes, and Movements." Asy-Syari'ah 26, no. 1 (2024): 41–62. https://doi.org/10.15575/as.v26i1.29639.
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Abstract: After the merger, three banks under State-Owned Enterprises (BUMN), namely BNI Syariah, BRI Syariah, and Bank Syariah Mandiri, became Bank Syariah Indonesia (BSI), opening opportunities for the development of Islamic financial institutions in Indonesia. However, according to the Masyarakat Tanpa Riba (Society Without Riba) (MTR), Islamic banks are not much different from conventional banks (BK). Therefore, the focus of this article is the law of usury in the view of the MTR, which is seen in three aspects, namely, the perception, attitude, and movement of the MTR. This paper aims to determine the law of usury from the view of the MTR. This article uses a qualitative research method, which is field research. Data collection techniques used are observation, interviews, and documents. The data analysis technique in this paper uses data condensation, data presentation, and conclusion. The study results show that the MTR is an anti-usury community. MTR can be categorised as a textualist and rigid group (mutasyadidun). The rigid MTR method often implies that Islamic economic development is static and monolithic. The existence of the MTR will be productive if it is read not as a threat but as an auto-criticism against Sharia financial practices that are not yet perfect, highlighting the potential impact of the MTR's perspective on Islamic financial practices.
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Skavatsou, Eleni, Maria Semitekolou, Ioannis Morianos, et al. "Immunotherapy Combined with Metronomic Dosing: An Effective Approach for the Treatment of NSCLC." Cancers 13, no. 8 (2021): 1901. http://dx.doi.org/10.3390/cancers13081901.
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Pioneering studies on tumor and immune cell interactions have highlighted immune checkpoint inhibitors (ICIs) as revolutionizing interventions for the management of NSCLC, typically combined with traditional MTD chemotherapies, which usually lead to toxicities and resistance to treatment. Alternatively, MTR chemotherapy is based on the daily low dose administration of chemotherapeutics, preventing tumor growth indirectly by targeting the tumor microenvironment. The effects of MTR administration of an oral prodrug of gemcitabine (OralGem), alone or with anti-PD1, were evaluated. Relevant in vitro and in vivo models were developed to investigate the efficacy of MTR alone or with immunotherapy and the potential toxicities associated with each dosing scheme. MTR OralGem restricted tumor angiogenesis by regulating thrombospondin-1 (TSP-1) and vascular endothelial growth factor A (VEGFA) expression. MTR OralGem enhanced antitumor immunity by increasing T effector responses and cytokine release, concomitant with dampening regulatory T cell populations. Promising pharmacokinetic properties afforded minimized blood and thymus toxicity and favorable bioavailability upon MTR administration compared to MTD. The combination of MTR OralGem with immunotherapy was shown to be highly efficacious and tolerable, illuminating it as a strong candidate therapeutic scheme for the treatment of NSCLC.
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Afshar, Abbas, and Ehsan Najafi. "Consequence management of chemical intrusion in water distribution networks under inexact scenarios." Journal of Hydroinformatics 16, no. 1 (2013): 178–88. http://dx.doi.org/10.2166/hydro.2013.125.
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The US Environmental Protection Agency (EPA)'s Response Protocol Toolbox provides a list of recommendations on actions that may be taken to minimize the potential threats to public health following a contamination threat. This protocol comprises three steps: (1) detection of contaminant presence, (2) source identification and (3) consequence management. This paper intends to explore consequence management under source uncertainty, applying Minimize Maximum Regret (MMR) and Minimize Total Regret (MTR) approaches. An ant colony optimization algorithm is coupled with the EPANET network solver for structuring the MMR and MTR models to present a robust method for consequence management by selecting the best combination of hydrants and valves for isolation and contamination flushing out of the system. The proposed models are applied to network number 3 of EPANET to present its effectiveness and capabilities in developing effective consequence management strategies.
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HT, Hidayat, and Emi Puspita Dewi. "Analisis Pengembangan Dakwah Islam Dalam Perspektif Teori Struktural Fungsionalisme." Jurnal Intelektualita: Keislaman, Sosial dan Sains 11, no. 2 (2022): 275–83. http://dx.doi.org/10.19109/intelektualita.v11i2.14239.
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Penelitian ini bertujuan untuk mendeskripsikan Majelis Tamasya Rohani (MTR) sebagai sebuah sistem sosial atau lembaga dakwah yang melakukan pengembangan dalam beberapa aspek dakwah Islam. Metode yang digunakan dalam penelitian ini adalah metode kualitatif deskriptif. Hasil penelitian ini menunjukkan bahwa MTR tidak hanya berhasil meneguhkan eksistensinya sebagai bagian dari lembaga dakwah, namun MTR mampu mengembangkan dakwah yang berawal dari metode bil lisan menjadi bil hal sehingga dakwah menjadi makin variatif. Dakwah yang tidak hanya membangun sisi ruhiyah umat tetapi sisi pendidikan, ekonomi dan budaya. MTR melakukan gerakan nyata untuk perbaikan umat dalam berbagai aktifitas atau programnya. Beberapa program dalam pengembangan dakwah tersebut seperti Program Durasi (Dhuafa Berprestasi), Rumah Tahfizh Supporting, Program Rihlah Ruhiyah dan Wisata Religi, Panti Asuhan Supporting, Khitanan Massal Gratis dan Simpul Jaring Dakwah MTR.
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Chen, Yinglun, Pu Wang, Yulong Bai, and Yuyuan Wang. "Effects of mirror training on motor performance in healthy individuals: a systematic review and meta-analysis." BMJ Open Sport & Exercise Medicine 5, no. 1 (2019): e000590. http://dx.doi.org/10.1136/bmjsem-2019-000590.
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ObjectiveMirror training (MTr) is a rehabilitation technique for patients with neurological diseases. There is no consensus on its effects on motor function in healthy individuals. This systematic review and meta-analysis considers the effects of MTr on motor function in healthy individuals.DesignThis is a systematic review and meta-analysis.Data sourcesWe searched six databases for studies assessing the effects of MTr on motor function in healthy individuals, published between January 1995 and December 2018. The Cochrane risk of bias was used to assess the quality of the studies. A meta-analysis was conducted with narrative synthesis.Eligibility criteria for selecting studiesEnglish-language randomised controlled trials reporting the behavioural results in healthy individuals were included.ResultsFourteen randomised controlled trials involving 538 healthy individuals were eligible. Two short-term studies showed MTr was inferior to passive vision pattern (standardised mean difference 0.57 (95% CI 0.06 to 1.08), I2=0%, p=0.03). The methods varied and there is limited evidence supporting the effectiveness of MTr compared with three alternative training patterns, with insufficient evidence to support analyses of age, skill level or hand dominance.ConclusionThe limited evidence that MTr affects motor performance in healthy individuals is weak and inconsistent among studies. It is unclear whether the effects of MTr on motor performance are more pronounced than the direct vision pattern, passive vision pattern or action observation. Further studies are needed to explore the short-term and long-term benefits of MTr and its effects on motor learning in healthy individuals.PROSPERO registration numberCRD42019128881.
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Várnai, Bianka, Ferenc Zsila, Zoltán Szakács, Zsófia Garádi, Milo Malanga, and Szabolcs Béni. "Sulfobutylation of Beta-Cyclodextrin Enhances the Complex Formation with Mitragynine: An NMR and Chiroptical Study." International Journal of Molecular Sciences 23, no. 7 (2022): 3844. http://dx.doi.org/10.3390/ijms23073844.
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Mitragynine (MTR), the main indole alkaloid of the well-known plant kratom (Mitragyna speciosa), is one of the most studied natural products nowadays, due to its remarkable biological effects. It is a partial agonist on the opioid receptors, and as such relieves pain without the well-known side-effects of the opioids applied in the clinical practice. MTR and its derivatives therefore became novel candidates for drug development. The poor aqueous solubility and low bioavailability of drugs are often improved by cyclodextrins (CyDs) as excipients through host-guest type complex formation. Among the wide variety of CyDs, sulfobutylether-beta-cyclodextrin (SBEβCyD) is frequently used and official in the European and U.S. Pharmacopoeia. Herein, the host-guest complexation of MTR with βCyD and SBEβCyD was studied using chiroptical and NMR spectroscopy. It was found by NMR measurements that MTR forms a rather weak (logβ11 = 0.8) 1:1 host-guest complex with βCyD, while the co-existence of the 2MTR∙SBEβCyD and MTR∙SBEβCyD species was deducted from 1H NMR titrations in the millimolar MTR concentration range. Sulfobutylation of βCyD significantly enhanced the affinity towards MTR. The structure of the formed inclusion complex was extensively studied by circular dichroism spectroscopy and 2D ROESY NMR. The insertion of the indole moiety was confirmed by both techniques.
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Mistry, Niraj, Rasha Abdel-Fahim, Olivier Mougin, Christopher Tench, Penny Gowland, and Nikos Evangelou. "Cortical lesion load correlates with diffuse injury of multiple sclerosis normal appearing white matter." Multiple Sclerosis Journal 20, no. 2 (2013): 227–33. http://dx.doi.org/10.1177/1352458513496344.
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Background:Degeneration of central nervous system normal appearing white matter (NAWM) underlies disability and progression in multiple sclerosis (MS). Axon loss typifies NAWM degeneration.Objective:The objective of this paper is to assess correlation between cortical lesion load and magnetisation transfer ratio (MTR) of the NAWM in MS. This was in order to test the hypothesis that cortical lesions cause NAWM degeneration.Methods:Nineteen patients with MS underwent 7 Tesla magnetisation-prepared-rapid-acquisition-gradient-echo (MPRAGE), and magnetisation transfer ratio (MTR) brain magnetic resonance imaging (MRI). Cortical lesions were identified using MPRAGE and MTR images of cortical ribbons. White matter lesions (WMLs) were segmented using MPRAGE images. WML maps were subtracted from white matter volumes to produce NAWM masks. Pearson correlation was calculated for NAWM MTR vs cortical lesion load, and WML volumes.Results:Cortical lesion volumes and counts all had significant correlation with NAWM mean MTR. The strongest correlation was with cortical lesion volumes obtained using MTR images ( r = −0.6874, p = 0.0006). WML volume had no significant correlation with NAWM mean MTR ( r = −0.08706, p = 0.3615).Conclusion:Our findings are consistent with the hypothesis that cortical lesions cause NAWM degeneration. This implicates cortical lesions in the pathogenesis of NAWM axon loss, which underpins long-term disability and progression in MS.
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Combès, Benoît, Anne Kerbrat, Jean Christophe Ferré, et al. "Focal and diffuse cervical spinal cord damage in patients with early relapsing–remitting MS: A multicentre magnetisation transfer ratio study." Multiple Sclerosis Journal 25, no. 8 (2018): 1113–23. http://dx.doi.org/10.1177/1352458518781999.
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Background: Studies including patients with well-established multiple sclerosis (MS) have shown a significant and disability-related reduction in the cervical spinal cord (SC) magnetisation transfer ratio (MTR). Objectives: The objectives are to (1) assess whether MTR reduction is already measurable in the SC of patients with early relapsing–remitting multiple sclerosis (RRMS) and (2) describe its spatial distribution. Methods: We included 60 patients with RRMS <12 months and 34 age-matched controls at five centres. Axial T2*w, sagittal T2w, sagittal phase-sensitive inversion recovery (PSIR), 3DT1w, and axial magnetisation transfer (MT) images were acquired from C1 to C7. Lesions were manually labelled and mean MTR values computed both for the whole SC and for normal-appearing SC in different regions of interest. Results: Mean whole SC MTR was significantly lower in patients than controls (33.7 vs 34.9 pu, p = 0.00005), even after excluding lesions (33.9 pu, p = 0.0003). We observed a greater mean reduction in MTR for vertebral levels displaying the highest lesion loads (C2–C4). In the axial plane, we observed a greater mean MTR reduction at the SC periphery and barycentre. Conclusion: Cervical SC tissue damage measured using MTR is not restricted to macroscopic lesions in patients with early RRMS and is not homogeneously distributed.
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Wigati, Sri. "PERCEPTION OF RIBA ACCORDING TO MTR-MASYARAKAT TANPA RIBA (A COMMUNITY WITHOUT USURY)." An-Nisbah: Jurnal Ekonomi Syariah 9, no. 1 (2022): 50–75. http://dx.doi.org/10.21274/an.v9i1.4837.
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ABSTRAK
 Lahirnya komunitas Masyarakat Tanpa Riba (MTR) ini dilatarbelakangi adanya dua alasan utama yaitu: pertama, keprihatinan atas Indonesia, negeri yang penduduknya mayoritas muslim namun secara sistemik dan massif melegalkan riba melalui adanya bank konvensional. Kedua, gerakan ini dilatarbelakangi dengan adanya kesadaran atas dasar konsep pemikiran cemerlang (akidah Islam) untuk membangkitkan umat muslim Indonesia dari keterpurukan multidimensi, khususnya jebakan dan jeratan ribawi.
 Penelitianinimerupakanpenelitiankualitatif dan menggunakanpenelitianlapangan (field research).Pendekatan yang digunakanadalahfenomenologi.Dalampengamatanmelihatperubahancaraberfikirmasyarakatdalamkehidupan. Teknikpengumpulan data denganobservasipastisipatif, wawancara dan dokumentasi. Hasil penelitian menunjukkan bahwa: .Tidak ada konsistensi terhadap sejarah munculnya MTR meskipun tidak sepakat terhadap bank, baik bank syariah maupun bank konvensional. Akan tetapi MTR juga tidak menunjukkan lembaga keuangan yang menurut MTR anti riba dan tetap memakai bank di Indonesia sebagai alat untuk sarana kegiatan MTR seperti bentuk transfer peserta dll.
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Anne, C., and L. Hansel. "L'emballage TN-MTR." Revue Générale Nucléaire, no. 3 (May 1999): 26–27. http://dx.doi.org/10.1051/rgn/19993026.
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Griffin, C. M., G. JM Parker, G. J. Barker, A. J. Thompson, and D. H. Miller. "MTR and T1 provide complementary information in MS NAWM, but not in lesions." Multiple Sclerosis Journal 6, no. 5 (2000): 327–31. http://dx.doi.org/10.1177/135245850000600506.
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MTR and T1 relaxation times are abnormal in MS lesions and NAWM, and may reflect tissue damage such as demyelination and axonal loss. Their relationship and potential to provide complementary information in tissue characterisation is explored. The aim of this study was to document the relationship between magnetisation transfer ratio (MTR) and T1 relaxation time in Multiple Sclerosis (MS) lesions and normal appearing white matter (NAWM) in order to determine whether the combination provides a more comprehensive tissue characterisation than either parameter in isolation. Ten patients with relapsing remitting MS and 10 age matched healthy controls underwent imaging using a protocol which included the measurement of both MTR and T1 relaxation times. The MTR and T1 values were compared statistically using a commonly adopted correlation approach and a mixed-model regression approach. There was a strong correlation between MTR and T1 in MS lesions (r=0.74). The correlation was seen equally in T1 hypointense and isointense lesions. The relationship was much weaker in MS NAWM (r=0.24) and no correlation was found in control white matter (r=0.06). Mixed-model regression analysis confirmed that the relationship between T1 and MTR is strongly dependent upon tissue type (MS lesion, MS NAWM, or control white matter). The relationship between MTR and T1 relaxation time measurements varies markedly between pathological and normal tissue types. In MS, the complementary information obtained from MTR and T1 is most apparent in NAWM. The results emphasise the potential for combinations of MR parameters to improve tissue characterisation, which in turn should improve understanding of disease pathology and treatment monitoring.
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Goytisolo, Fermín A., Enrique Samper, Juan Martín-Caballero, et al. "Short Telomeres Result in Organismal Hypersensitivity to Ionizing Radiation in Mammals." Journal of Experimental Medicine 192, no. 11 (2000): 1625–36. http://dx.doi.org/10.1084/jem.192.11.1625.
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Here we show a correlation between telomere length and organismal sensitivity to ionizing radiation (IR) in mammals. In particular, fifth generation (G5) mouse telomerase RNA (mTR)−/− mice, with telomeres 40% shorter than in wild-type mice, are hypersensitive to cumulative doses of gamma rays. 60% of the irradiated G5 mTR−/− mice die of acute radiation toxicity in the gastrointestinal tract, lymphoid organs, and kidney. The affected G5 mTR−/− mice show higher chromosomal damage and greater apoptosis than similarly irradiated wild-type controls. Furthermore, we show that G5 mTR−/− mice show normal frequencies of sister chromatid exchange and normal V(D)J recombination, suggesting that short telomeres do not significantly affect the efficiency of DNA double strand break repair in mammals. The IR-sensitive phenotype of G5 mTR−/− mice suggests that telomere function is one of the determinants of radiation sensitivity of whole animals.
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Xiao, Chunlin, and Mosbah M. Kushad. "Reduced 5'-Methylthioadenosine Nucleosidase and 5-Methylthioribose Activities and Ethylene Biosynthesis in Nonripening Tomato Mutants `Rin' and `Nor' Relative to Ripening Tomato `Rutgers'." HortScience 31, no. 4 (1996): 687f—688. http://dx.doi.org/10.21273/hortsci.31.4.687f.
Full textAbstract:
5'-methylthioadenosine (MTA) nucleosidase (EC.2.2.2.28) and 5-methylthioribose (MTR) kinase (EC.2.7.1.100) activities were evaluated in `rin', `nor', and `Rutgers' tomato fruit during development and ripening. Changes in the activities of these enzymes were compared to ethylene biosynthesis. MTA nucleosidase and MTR kinase activities in `rin' and `nor' were ≈30% and 22%, respectively, lower than `Rutgers' during the first 2 weeks of fruit development. In `Rutgers', activities of these enzymes declined sharply until fruit maturity. Shortly before climacteric rise in ethylene synthesis, MTA nucleosidase, and MTR kinase activities increased, reaching a maximum level before peak ethylene synthesis then declined when fruit started to approach senescence. Whereas, `rin' and `nor' mutants exhibited no climacteric rise in ethylene synthesis and no change in MTA nucleosidase or MTR kinase activities, following their decline after 2 weeks of growth. A rapid increase in ethylene synthesis was observed when mature green `rin' and `nor' fruit were wounded. This increase in ethylene was paralleled by an increase in MTA nucleosidase and MTR kinase activities. However, increase in wound ethylene, MTA nucleosidase, and MTR kinase activities in `rin' and `nor' was ≈40% less than what we had previously reported in `Rutgers'. Relationship of MTA and MTR kinase activities to fruit growth, development, ripening, and natural and wound ethylene biosynthesis will be described.
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Koo, Kenneth, and W. Dorsey Stuart. "Sequence and structure of mtr, an amino acid transport gene of Neurospora crassa." Genome 34, no. 4 (1991): 644–51. http://dx.doi.org/10.1139/g91-098.
Full textAbstract:
The gene product of the mtr locus of Neurospora crassa is required for the transport of neutral aliphatic and aromatic amino acids via the N system. We have previously cloned three cosmids containing Neurospora DNA that complement the mtr-6(r) mutant allele. The cloned DNAs were tightly linked to restriction fragment length polymorphisms that flank the mtr locus. A 2.9-kbp fragment from one cosmid was subcloned and found to complement the mtr-6(r) allele. Here we report the sequence of the fragment that hybridized to a poly(A)+ mRNA transcript of about 2300 nucleotides. We have identified an 845-bp open reading frame (ORF) having a 59-bp intron as the potential mtr ORF. S1 nuclease analysis of the transcript confirmed the transcript size and the presence of the intron. A second open reading frame was found upstream in the same reading frame as the mtr ORF and appears to be present in the mRNA transcript. The mtr ORF is predicted to encode a 261 amino acid polypeptide with a molecular mass of 28 613 Da. The proposed polypeptide exhibits six potential α-helical transmembrane domains with an average length of 23 amino acids, does not have a signal sequence, and contains amino acid sequence homologous to an RNA binding motif.Key words: sequence, membranes, ribonucleoprotein.
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Mallik, Shahrukh, Nils Muhlert, Rebecca S. Samson, et al. "Regional patterns of grey matter atrophy and magnetisation transfer ratio abnormalities in multiple sclerosis clinical subgroups: A voxel-based analysis study." Multiple Sclerosis Journal 21, no. 4 (2014): 423–32. http://dx.doi.org/10.1177/1352458514546513.
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Background: In multiple sclerosis (MS), demyelination and neuro-axonal loss occur in the brain grey matter (GM). We used magnetic resonance imaging (MRI) measures of GM magnetisation transfer ratio (MTR) and volume to assess the regional localisation of reduced MTR (reflecting demyelination) and atrophy (reflecting neuro-axonal loss) in relapsing–remitting MS (RRMS), secondary progressive MS (SPMS) and primary progressive MS (PPMS). Methods: A total of 98 people with MS (51 RRMS, 28 SPMS, 19 PPMS) and 29 controls had T1-weighted volumetric and magnetisation transfer scans. SPM8 was used to undertake voxel-based analysis (VBA) of GM tissue volumes and MTR. MS subgroups were compared with controls, adjusting for age and gender. A voxel-by-voxel basis correlation analysis between MTR and volume within each subject group was performed, using biological parametric mapping. Results: MTR reduction was more extensive than atrophy. RRMS and SPMS patients showed proportionately more atrophy in the deep GM. SPMS and PPMS patients showed proportionately greater cortical MTR reduction. RRMS patients demonstrated the most correlation of MTR reduction and atrophy in deep GM. In SPMS and PPMS patients, there was less extensive correlation. Conclusions: These results suggest that in the deep GM of RRMS patients, demyelination and neuro-axonal loss may be linked, while in SPMS and PPMS patients, neuro-axonal loss and demyelination may occur mostly independently.
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Elvey, Anne. "Homogenizing Violence, Isa 40:4 (and Luke 3:5) and MTR (Mountaintop Removal Mining)." Worldviews 19, no. 3 (2015): 226–44. http://dx.doi.org/10.1163/15685357-01903002.
Full textAbstract:
With the metaphor of leveling hills and filling valleys, Isa 40:4 presents an image of homogenizing violence toward Earth. This biblical text has been adopted by proponents of Mountaintop Removal Mining (hereafter, MTR). Justification of MTR by explicit reference to Isa 40:4 has occurred principally in response to Christian protests against MTR. The same text has been used by those resisting MTR. This article begins with ecophilosopher Val Plumwood’s critique of homogenization and draws on Paul Ricoeur’s reading of Aristotle on metaphor, to ask if, other than as a crass use as a proof-text for MTR, the application of Isa 40:4 to this destructive practice points to a deeper problem with homogenizing metaphors whose content is other-than-human. While the Isaian metaphor is problematic, it is grounded in the underlying liveliness of its subject. Attention to the liveliness of these biblical mountains and valleys allows that the text, and its metaphors, can also empower resistance to MTR. The liveliness underlying the mountains and hills of the Isaian metaphor can prompt a renewed focus on, and solidarity with, the Appalachian mountains and their communities.
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Kim, Jae-Woong, Jiye Choi, Janggeun Cho, Chulhyun Lee, Daejong Jeon, and Sung-Hong Park. "Preliminary Observations on Sensitivity and Specificity of Magnetization Transfer Asymmetry for Imaging Myelin of Rat Brain at High Field." BioMed Research International 2015 (2015): 1–10. http://dx.doi.org/10.1155/2015/565391.
Full textAbstract:
Magnetization transfer ratio (MTR) has been often used for imaging myelination. Despite its high sensitivity, the specificity of MTR to myelination is not high because tissues with no myelin such as muscle can also show high MTR. In this study, we propose a new magnetization transfer (MT) indicator, MT asymmetry (MTA), as a new method of myelin imaging. The experiments were performed on rat brain at 9.4 T. MTA revealed high signals in white matter and significantly low signals in gray matter and muscle, indicating that MTA has higher specificity than MTR. Demyelination and remyelination studies demonstrated that the sensitivity of MTA to myelination was as high as that of MTR. These experimental results indicate that MTA can be a good biomarker for imaging myelination. In addition, MTA images can be efficiently acquired with an interslice MTA method, which may accelerate clinical application of myelin imaging.
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Rausch, M., PS Tofts, P. Lervik, et al. "Characterization of white matter damage in animal models of multiple sclerosis by magnetization transfer ratio and quantitative mapping of the apparent bound proton fraction f*." Multiple Sclerosis Journal 15, no. 1 (2009): 16–27. http://dx.doi.org/10.1177/1352458508096006.
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Quantitative magnetization transfer magnetic resonance imaging (qMT-MRI) can be used to improve detection of white matter tissue damage in multiple sclerosis (MS) and animal models thereof. To study the correlation between MT parameters and tissue damage, the magnetization transfer ratio (MTR), the parameter f* (closely related to the bound proton fraction) and the bound proton transverse relaxation time T2B of lesions in a model of focal experimental autoimmune encephalomyelitis (EAE) were measured on a 7T animal scanner and data were compared with histological markers indicative for demyelination, axonal density, and tissue damage. A clear spatial correspondence was observed between reduced values of MTR and demyelination in this animal model. We observed two different levels of MTR and f* reduction for these lesions. One was characterized by a pronounced demyelination and the other corresponded to a more severe loss of the cellular matrix. Changes in f* were generally more pronounced than those of MTR in areas of demyelination. Moreover, a reduction of f* was already observed for tissue where MTR was virtually normal. No changes in T2B were observed for the lesions. We conclude that MTR and qMT mapping are efficient and reliable readouts for studying demyelination in animal models of MS, and that the analysis of regional f* might be even superior to the analysis of MTR values. Therefore, quantitative mapping of f* from human brains might also improve the detection of white matter damage in MS.
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Maeda, Shoji, Qianhui Qu, Michael J. Robertson, Georgios Skiniotis, and Brian K. Kobilka. "Structures of the M1 and M2 muscarinic acetylcholine receptor/G-protein complexes." Science 364, no. 6440 (2019): 552–57. http://dx.doi.org/10.1126/science.aaw5188.
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Muscarinic acetylcholine receptors are G protein–coupled receptors that respond to acetylcholine and play important signaling roles in the nervous system. There are five muscarinic receptor subtypes (M1R to M5R), which, despite sharing a high degree of sequence identity in the transmembrane region, couple to different heterotrimeric GTP-binding proteins (G proteins) to transmit signals. M1R, M3R, and M5R couple to the Gq/11 family, whereas M2R and M4R couple to the Gi/o family. Here, we present and compare the cryo–electron microscopy structures of M1R in complex with G11 and M2R in complex with GoA. The M1R-G11 complex exhibits distinct features, including an extended transmembrane helix 5 and carboxyl-terminal receptor tail that interacts with G protein. Detailed analysis of these structures provides a framework for understanding the molecular determinants of G-protein coupling selectivity.
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Mesaros, S., MA Rocca, MP Sormani, et al. "Bimonthly assessment of magnetization transfer magnetic resonance imaging parameters in multiple sclerosis: a 14-month, multicentre, follow-up study." Multiple Sclerosis Journal 16, no. 3 (2010): 325–31. http://dx.doi.org/10.1177/1352458509358713.
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This study was performed to assess the temporal evolution of damage within lesions and the normal-appearing white matter, measured using frequent magnetization transfer (MT) MRI, in relapsing—remitting multiple sclerosis (RRMS). The relationship of MT ratio (MTR) changes with measures of lesion burden, and the sample sizes needed to demonstrate a treatment effect on MTR metrics in placebo-controlled MS trials were also investigated. Bimonthly brain conventional and MT MRI scans were acquired from 42 patients with RRMS enrolled in the placebo arm of a 14-month, double-blind trial. Longitudinal MRI changes were evaluated using a random effect linear model accounting for repeated measures, and adjusted for centre effects. The Expanded Disability Status Scale (EDSS) score remained stable over the study period. A weak, but not statistically significant, decrease over time was detected for normal-appearing brain tissue (NABT) average MTR (—0.02% per visit; p = 0.14), and MTR peak height (—0.15 per visit; p = 0.17), while average lesion MTR showed a significant decrease over the study period (—0.07% per visit; p = 0.03). At each visit, all MTR variables were significantly correlated with T2 lesion volume (LV) (average coefficients of correlation ranging from —0.54 to —0.28, and p-values from <0.001 to 0.02). At each visit, NABT average MTR was also significantly correlated with T1-hypointense LV (average coefficient of correlation = —0.57, p < 0.001). The estimation of the sample sizes required to demonstrate a reduction of average lesion MTR (the only parameter with a significant decrease over the follow-up) ranged from 101 to 154 patients to detect a treatment effect of 50% in a 1-year trial with a power of 90%. The steady correlation observed between conventional and MT MRI measures over time supports the hypothesis of axonal degeneration of fibres passing through focal lesions as one of the factors contributing to the overall MS burden.
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Moccia, Marcello, Steven van de Pavert, Arman Eshaghi, et al. "Pathologic correlates of the magnetization transfer ratio in multiple sclerosis." Neurology 95, no. 22 (2020): e2965-e2976. http://dx.doi.org/10.1212/wnl.0000000000010909.
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ObjectiveTo identify pathologic correlates of magnetization transfer ratio (MTR) in multiple sclerosis (MS) in an MRI–pathology study.MethodsWe acquired MTR maps at 3T from 16 fixed MS brains and 4 controls, and immunostained 100 tissue blocks for neuronal neurofilaments, myelin (SMI94), tissue macrophages (CD68), microglia (IBA1), B-lymphocytes, T-lymphocytes, cytotoxic T-lymphocytes, astrocytes (glial fibrillary acidic protein), and mitochondrial damage (COX4, VDAC). We defined regions of interest in lesions, normal-appearing white matter (NAWM), and cortical normal-appearing gray matter (NAGM). Associations between MTR and immunostaining intensities were explored using linear mixed-effects models (with cassettes nested within patients) and interaction terms (for differences between regions of interest and between cases and controls); a multivariate linear mixed-effects model identified the best pathologic correlates of MTR.ResultsMTR was the lowest in white matter (WM) lesions (23.4 ± 9.4%) and the highest in NAWM (38.1 ± 8.7%). In MS brains, lower MTR was associated with lower immunostaining intensity for myelin (coefficient 0.31; 95% confidence interval [CI] 0.07–0.55), macrophages (coefficient 0.03; 95% CI 0.01–0.07), and astrocytes (coefficient 0.51; 95% CI 0.02–1.00), and with greater mitochondrial damage (coefficient 0.31; 95% CI 0.07–0.55). Based on interaction terms, MTR was more strongly associated with myelin in WM (coefficient 1.58; 95% CI 1.09–2.08) and gray matter (GM) lesions (coefficient 0.66; 95% CI 0.13–1.20), and with macrophages (coefficient 1.40; 95% CI 0.56–2.25), astrocytes (coefficient 2.66; 95% CI 1.31–4.01), and mitochondrial damage (coefficient −12.59; 95% CI −23.16 to −2.02) in MS brains than controls. In the multivariate model, myelin immunostaining intensity was the best correlate of MTR (coefficient 0.31; 95% CI 0.09–0.52; p = 0.004).ConclusionsMyelin was the strongest correlate of MTR, especially in WM and cortical GM lesions, but additional correlates should be kept in mind when designing and interpreting MTR observational and experimental studies in MS.
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Guedes, Tarciana, Aline A. Santos, Felipe H. Vieira-Neto, Bianca Bianco, Caio P. Barbosa, and Denise M. Christofolini. "Folate metabolism abnormalities in infertile patients with endometriosis." Biomarkers in Medicine 16, no. 7 (2022): 549–57. http://dx.doi.org/10.2217/bmm-2021-0076.
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Background: Homocysteine levels can be impacted by enzymes variations. Aim: To correlate MTHFR, MTR and MTRR variants with homocysteine levels in the blood and follicular fluid and assisted reproduction results. Material & methods: MTHFR (rs2274976, rs1801131, rs1801133), MTR (rs1805087) and MTRR (rs1801394) genotyping was performed by TaqMan assays and compared with homocysteine levels, measured by ELISA, to oocytes retrieved and to the pregnancy status of women with endometriosis and controls. Results: The MTR G allele and GG genotype were more common in patients with endometriosis. They also showed lower levels of homocysteine and more clinical gestations. Epistasis analysis showed a model associated with gestational results, composed of MTHFR+MTR variants (CC+AG). Conclusion: The summation effect of variants in genes participating in folate metabolism was associated with pregnancy status in Brazilian women. MTR variants were more observed in endometriosis patients, as well as lower follicular Hcy levels and increased clinical pregnancy results.
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Patel, Y., J. Shin, P. A. Gowland, Z. Pausova, and T. Paus. "Maturation of the Human Cerebral Cortex During Adolescence: Myelin or Dendritic Arbor?" Cerebral Cortex 29, no. 8 (2018): 3351–62. http://dx.doi.org/10.1093/cercor/bhy204.
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Abstract Previous in vivo studies revealed robust age-related variations in structural properties of the human cerebral cortex during adolescence. Neurobiology underlying these maturational phenomena is largely unknown. Here we employ a virtual-histology approach to gain insights into processes associated with inter-regional variations in cortical microstructure and its maturation, as indexed by magnetization transfer ratio (MTR). Inter-regional variations in MTR correlate with inter-regional variations in expression of genes specific to pyramidal cells (CA1) and ependymal cells; enrichment analyses indicate involvement of these genes in dendritic growth. On the other hand, inter-regional variations in the change of MTR during adolescence correlate with inter-regional profiles of oligodendrocyte-specific gene expression. Complemented by a quantitative hypothetical model of the contribution of surfaces associated with dendritic arbor (1631 m2) and myelin (48 m2), these findings suggest that MTR signals are driven mainly by macromolecules associated with dendritic arbor while maturational changes in the MTR signal are associated with myelination.
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Stuart, W. Dorsey, Kenneth Koo, and Steven J. Vollmer. "Cloning of mtr, an amino acid transport gene of Neurospora crassa." Genome 30, no. 2 (1988): 198–203. http://dx.doi.org/10.1139/g88-034.
Full textAbstract:
Translocation of neutral aliphatic and aromatic amino acids across the plasma membrane of the ascomycete Neurospora crassa requires a functional gene product of the mtr locus. Mutations at this locus are defective in transport of those amino acids. We have cloned the mtr+ gene of Neurospora crassa from an ordered cosmid library of genomic DNA and produced a preliminary restriction map of 2.9 kilobases of genomic DNA that encompasses the mtr coding region. We have confirmed that the cloned DNA regions contain the mtr gene sequence by restriction fragment length polymorphism mapping and have determined that the cloned sequence codes for a messenger RNA transcript of approximately 1200 nucleotides in length.Key words: transformation, methyltryptophane resistance, Neurospora.