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1
Yan, Xin, and Yang Sheng Ye. "Research on Test of Reducing Deformation of Soft Rock Tunnel with High Stress Level by Pilot Heading." Applied Mechanics and Materials 170-173 (May 2012): 1565–68. http://dx.doi.org/10.4028/www.scientific.net/amm.170-173.1565.
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Generally speaking, the pilot heading is aways used for geological exploration，speeding up the construction，improving the draining and Ventilation condition, promoting efficiency of residue transporting. When tunneling on high ground stress soft rock region，the pilot heading will play a more important role. Lan yu line Mu Zhai ling tunnel main passes through the region of carbonaceous slate. Due to the high ground stresses, the primary reinforcement system underwent large deformation, evenmore the lining is cracked. Through excaving the pilot heading, can relief the stress. Then enlarg the pilot heading to main tunnel, the deformation of primary support will be reduced, and the tunnel will be stable. Compare the "pilot and enlarging" excavation method with bench excavation method on surrounding rock deformation. As the result, the "pilot and enlarging" excavation method is effective for control of the deformation of the tunnel.
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Mu, Qing, Jun Liang, Xiaoxin Zhou, Gen Li, and Xing Zhang. "A node splitting interface algorithm for multi-rate parallel simulation of DC grids." CSEE Journal of Power and Energy Systems 4, no. 3 (September 24, 2018): 388–97. http://dx.doi.org/10.17775/cseejpes.2017.01170.
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Myers, P., S. Stathakis, C. Buckey, and N. Papanikolaou. "VMAT monthly QA using two techniques: 2D ion chamber array with an isocentric gantry mount and an in vivo dosimetric device attached to gantry." Journal of Radiotherapy in Practice 13, no. 2 (April 22, 2013): 240–46. http://dx.doi.org/10.1017/s1460396912000556.
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AbstractPurposeVarian RapidArc is a volumetric modulated arc therapy (VMAT) that obtains a conformal dose around the desired structure by employing variable gantry speed, dose rate and dynamic multileaf collimator (DMLC) speed as the gantry rotates about machine isocenter. This study is meant to build upon previous research by Ling et al. by completing the tests with an in vivo dosimetric device attached to the linac gantry and a 2D ionisation chamber array with an isocentric gantry mount.Materials and methodsTwo PTW detectors, seven29 array with gantry mount and DAVID, were attached to the linear accelerator gantry, allowing each device to remain perpendicular to the beam at all gantry angles. Three tests for RapidArc evaluation were performed on these devices including: dose rate and gantry speed variation, DMLC speed and dose rate variation and DMLC position accuracy. The reproducibility of the arc data was also reported.ResultsA picket fence plan varying dose rates (111 to 600 MU/minute) and gantry speeds (5·5 to 4·3°/second) was delivered consisting of seven sections of different combinations. These measurements were compared with static gantry, open field measurements and found to be within 2·39% for the DAVID device and 0·84% for the seven29. A four-section picket fence of varying DMLC speeds (0·46, 0·92, 1·84 and 2·76 cm/second) was similarly evaluated and found to be within 1·99% and 3·66% for the DAVID and seven29, respectively. For DMLC position accuracy, a picket fence arc plan was compared with a static picket fence and found to agree within 0.38% and 2.91%. Reproducibility for these three RapidArc plans was found to be within 0·30% and 2·70% for the DAVID and seven29.ConclusionThe DAVID and seven29 detectors were able to perform the RapidArc quality assurance tests efficiently and accurately and the results were reproducible. Periodic verification of DMLC movement, dose rate variation and gantry speed variation relating to RapidArc delivery can be completed in a timelier manner using this equipment.
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Robertson, Donald S. "GENETIC STUDIES ON THE LOSS OF Mu MUTATOR ACTIVITY IN MAIZE." Genetics 113, no. 3 (July 1, 1986): 765–73. http://dx.doi.org/10.1093/genetics/113.3.765.
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ABSTRACT Mutator activity of the Mu mutator system of maize can be lost by either outcrossing or inbreeding Mu stocks. The nature of these two kinds of Mu-loss phenomena was analyzed by testing the results of crossing Mu-loss stocks by active Mu lines. Outcross-Mu-loss stocks are capable of supporting Mu activity if crossed by an active mutator line. Inbred-Mu-loss stocks, however, inactivate the active Mu system contributed by a Mu line. Also, inbred-Mu-loss lines do not regain Mu activity after at least three generations of outcrossing to non-Mu stocks. These results suggest that, once the Mu system is inactivated by inbreeding, it remains inactivated for at least three generations of outcrossing. Further, once the system responsible for inactivation is established, it will, in turn, inactivate an active Mu system contributed by crossing with Mu plants. The outcross-Mu-loss does not seem to involve such an inactivation system. These results are interpreted in the light of recent evidence that Mu inactivation results from the modification of Mu 1 transposable elements involved in the Mu phenotype.
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Baker, M. D., and L. R. Read. "Ectopic recombination within homologous immunoglobulin mu gene constant regions in a mouse hybridoma cell line." Molecular and Cellular Biology 12, no. 10 (October 1992): 4422–32. http://dx.doi.org/10.1128/mcb.12.10.4422.
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We have transferred a pSV2neo vector containing the wild-type constant region of the immunoglobulin mu gene (C mu) into the mutant hybridoma igm482, which bears a 2-bp deletion in the third constant-region exon of its haploid chromosomal mu gene (C mu 3). Independent igm482 transformants contain the wild-type immunoglobulin C mu region stably integrated in ectopic chromosomal positions. We report here that the wild-type immunoglobulin C mu region can function as the donor sequence in a gene conversion event which corrects the 2-bp deletion in the mutant igm482 chromosomal C mu 3 exon. The homologous recombination event restores normal immunoglobulin M production in the mutant cell.
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Baker, M. D., and L. R. Read. "Ectopic recombination within homologous immunoglobulin mu gene constant regions in a mouse hybridoma cell line." Molecular and Cellular Biology 12, no. 10 (October 1992): 4422–32. http://dx.doi.org/10.1128/mcb.12.10.4422-4432.1992.
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We have transferred a pSV2neo vector containing the wild-type constant region of the immunoglobulin mu gene (C mu) into the mutant hybridoma igm482, which bears a 2-bp deletion in the third constant-region exon of its haploid chromosomal mu gene (C mu 3). Independent igm482 transformants contain the wild-type immunoglobulin C mu region stably integrated in ectopic chromosomal positions. We report here that the wild-type immunoglobulin C mu region can function as the donor sequence in a gene conversion event which corrects the 2-bp deletion in the mutant igm482 chromosomal C mu 3 exon. The homologous recombination event restores normal immunoglobulin M production in the mutant cell.
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Richings, Alexander J., Claude-André Faucher-Giguère, and Jonathan Stern. "Unravelling the physics of multiphase AGN winds through emission line tracers." Monthly Notices of the Royal Astronomical Society 503, no. 2 (February 27, 2021): 1568–85. http://dx.doi.org/10.1093/mnras/stab556.
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ABSTRACT Observations of emission lines in active galactic nuclei (AGNs) often find fast (∼1000 km s−1) outflows extending to kiloparsec scales, seen in ionized, neutral atomic and molecular gas. In this work we present radiative transfer calculations of emission lines in hydrodynamic simulations of AGN outflows driven by a hot wind bubble, including non-equilibrium chemistry, to explore how these lines trace the physical properties of the multiphase outflow. We find that the hot bubble compresses the line-emitting gas, resulting in higher pressures than in the ambient interstellar medium or that would be produced by the AGN radiation pressure. This implies that observed emission line ratios such as [O iv]$_{25 \, \rm {\mu m}}$ / [Ne ii]$_{12 \, \rm {\mu m}}$, [Ne v]$_{14 \, \rm {\mu m}}$ / [Ne ii]$_{12 \, \rm {\mu m}}$, and [N iii]$_{57 \, \rm {\mu m}}$ / [N ii]$_{122 \, \rm {\mu m}}$ constrain the presence of the bubble and hence the outflow driving mechanism. However, the line-emitting gas is under-pressurized compared to the hot bubble itself, and much of the line emission arises from gas that is out of pressure, thermal and/or chemical equilibrium. Our results thus suggest that assuming equilibrium conditions, as commonly done in AGN line emission models, is not justified if a hot wind bubble is present. We also find that ≳50 per cent of the mass outflow rate, momentum flux, and kinetic energy flux of the outflow are traced by lines such as [N ii]$_{122 \, \rm {\mu m}}$ and [Ne iii]$_{15 \, \rm {\mu m}}$ (produced in the 10$^{4} \, \rm {K}$ phase) and [C ii]$_{158 \, \rm {\mu m}}$ (produced in the transition from 10$^{4} \, \rm {K}$ to 100 K).
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Shapiro, A. M., M. S. Schlissel, D. Baltimore, and A. L. DeFranco. "Stimulation of kappa light-chain gene rearrangement by the immunoglobulin mu heavy chain in a pre-B-cell line." Molecular and Cellular Biology 13, no. 9 (September 1993): 5679–90. http://dx.doi.org/10.1128/mcb.13.9.5679.
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B-lymphocyte development exhibits a characteristic order of immunoglobulin gene rearrangements. Previous work has led to the hypothesis that expression of the immunoglobulin mu heavy chain induces rearrangement activity at the kappa light-chain locus. To examine this issue in more detail, we isolated five matched pairs of mu- and endogenously rearranged mu+ cell lines from the Abelson murine leukemia virus-transformed pro-B-cell line K.40. In four of the five mu+ cell lines, substantial expression of mu protein on the cell surface was observed, and this correlated with an enhanced frequency of kappa immunoglobulin gene rearrangement compared with that in the matched mu- cell lines. This increased kappa gene rearrangement frequency was not due to a general increase in the amount of V(D)J recombinase activity in the mu+ cells. Consistently, introduction of a functionally rearranged mu gene into one of the mu- pre-B-cell lines resulted in a fivefold increase in kappa gene rearrangements. In three of the four clonally matched pairs with increased kappa gene rearrangements, the increase in rearrangement frequency was not accompanied by a significant increase in germ line transcripts from the C kappa locus. However, in the fourth pair, K.40D, we observed an increase in germ line transcription of the kappa locus after expression of mu protein encoded by either an endogenously rearranged or a transfected functional heavy-chain allele. In these cells, the amount of the germ line C kappa transcript correlated with the measured frequency of rearranged kappa genes. These results support a regulated model of B-cell development in which mu protein expression in some way targets the V(D)J recombinase to the kappa gene locus.
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Shapiro, A. M., M. S. Schlissel, D. Baltimore, and A. L. DeFranco. "Stimulation of kappa light-chain gene rearrangement by the immunoglobulin mu heavy chain in a pre-B-cell line." Molecular and Cellular Biology 13, no. 9 (September 1993): 5679–90. http://dx.doi.org/10.1128/mcb.13.9.5679-5690.1993.
Full textAbstract:
B-lymphocyte development exhibits a characteristic order of immunoglobulin gene rearrangements. Previous work has led to the hypothesis that expression of the immunoglobulin mu heavy chain induces rearrangement activity at the kappa light-chain locus. To examine this issue in more detail, we isolated five matched pairs of mu- and endogenously rearranged mu+ cell lines from the Abelson murine leukemia virus-transformed pro-B-cell line K.40. In four of the five mu+ cell lines, substantial expression of mu protein on the cell surface was observed, and this correlated with an enhanced frequency of kappa immunoglobulin gene rearrangement compared with that in the matched mu- cell lines. This increased kappa gene rearrangement frequency was not due to a general increase in the amount of V(D)J recombinase activity in the mu+ cells. Consistently, introduction of a functionally rearranged mu gene into one of the mu- pre-B-cell lines resulted in a fivefold increase in kappa gene rearrangements. In three of the four clonally matched pairs with increased kappa gene rearrangements, the increase in rearrangement frequency was not accompanied by a significant increase in germ line transcripts from the C kappa locus. However, in the fourth pair, K.40D, we observed an increase in germ line transcription of the kappa locus after expression of mu protein encoded by either an endogenously rearranged or a transfected functional heavy-chain allele. In these cells, the amount of the germ line C kappa transcript correlated with the measured frequency of rearranged kappa genes. These results support a regulated model of B-cell development in which mu protein expression in some way targets the V(D)J recombinase to the kappa gene locus.
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Marks, R., and M. J. Bosma. "Truncated mu (mu') chains in murine IgM. Evidence that mu' chains lack variable regions." Journal of Experimental Medicine 162, no. 6 (December 1, 1985): 1862–77. http://dx.doi.org/10.1084/jem.162.6.1862.
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Secreted IgM was shown to contain truncated mu (mu') chains with an apparent molecular mass of approximately 55 kD. The estimated percentage of IgM heavy (H) chains in the mu' form ranged from less than or equal to 1% in the case of one tumor IgM protein (104E) to greater than or equal to 30% in normal serum IgM. Serum mu' chains lacked antigenic determinants characteristic of immunoglobulin variable regions and showed a restricted isoelectric focusing pattern compared with that of conventional mu chains. Intracellular mu' chains were readily detected in bone marrow cells but not in spleen or lymph node cells; mu' chains were also detected in IgM-producing tumor cells and in a hybridoma cell line that deleted its productive mu allele. These results predict irregularities in IgM structure and recall an old controversy concerning the valence of IgM molecules.
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Yang, Shengqi, Adam Lidz, and Gergö Popping. "The prospects for observing [O iii] 52 micron emission from galaxies during the Epoch of Reionization." Monthly Notices of the Royal Astronomical Society 504, no. 1 (April 1, 2021): 723–30. http://dx.doi.org/10.1093/mnras/stab925.
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ABSTRACT The [O iii] 88 $\mu$m fine-structure emission line has been detected into the Epoch of Reionization (EoR) from star-forming galaxies at redshifts 6 < z ≲ 9 with ALMA. These measurements provide valuable information regarding the properties of the interstellar medium (ISM) in the highest redshift galaxies discovered thus far. The [O iii] 88 $\mu$m line observations leave, however, a degeneracy between the gas density and metallicity in these systems. Here, we quantify the prospects for breaking this degeneracy using future ALMA observations of the [O iii] 52 $\mu$m line. Among the current set of 10 [O iii] 88 $\mu$m emitters at 6 < z ≲ 9, we forecast 52 $\mu$m detections (at 6σ) in SXDF-NB1006-2, B14-6566, J0217-0208, and J1211-0118 within on-source observing times of 2–10 h, provided their gas densities are larger than about nH ≳ 102–103 cm−3. Other targets generally require much longer integration times for a 6σ detection. Either successful detections of the 52 $\mu$m line or reliable upper limits will lead to significantly tighter constraints on ISM parameters. The forecasted improvements are as large as ∼3 dex in gas density and ∼1 dex in metallicity for some regions of parameter space. We suggest SXDF-NB1006-2 as a promising first target for 52 $\mu$m line measurements. We discuss how such measurements will help in understanding the mass–metallicity relationship during the EoR.
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Shen, Hu, Shaohe Lv, Xuan Dong, Junquan Deng, Xiaodong Wang, and Xingming Zhou. "Hypergraph Modeling and Approximation Algorithms for the Minimum Length Link Scheduling in Multiuser MIMO Networks." Journal of Applied Mathematics 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/982713.
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This paper investigates the problem of the minimum length link scheduling (MLLS) in multiuser MIMO (MU-MIMO) networks. Generally, in the networks with MU-MIMO capability, the number of concurrent transmissions can be as large as that of antenna elements at the receiver. As a result, link interference is no longer binary but demonstrates a strong correlation among multiple links, which cannot be captured by the conventional conflict graph interference model. Hence, we propose a novel hypergraph interference model, which can accurately and efficiently characterize the relationship of multiple interferences induced by concurrent transmissions, and provide a tractable formalization of the minimum length link scheduling in MU-MIMO networks (MU-MIMO MLLS). Afterwards, we prove that the MU-MIMO MLLS problem is NP-hard and introduce two approximation algorithms to find the near-optimal feasible schedule. Finally, extensive simulation experiments are presented.
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Bakirci Ureyen, Sibel, Rabia Oztas Kara, Zeynep Erturk, and Mahizer Yaldiz. "The microvascular and morphostructural changes of nails in psoriatic patients with nail disease; a link between ultrasound and videocapillaroscopy findings in the nailfold." Medical Ultrasonography 20, no. 2 (May 2, 2018): 185. http://dx.doi.org/10.11152/mu-1274.
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Objective: The objective of this study is to evaluate the link between nail fold vessel resistive index (NVRI) measured by ultrasound (US) and capillary loops diameters measured using nailfold videocapillarascopy (NVC), and to assess the morphological appearance of the nail bed in patients with psoriatic nail disease (PND) as compared with healthy controls (HCs).Material and methods: This study was conducted in patients with PND and HCs. General demographic data were collected and clinical assessments were performed for all subjects. The nail plate thickness (NPT) was measured on gray scale using US. The NVRI was measured using color Doppler (CD) US. The measurements of the apical, arterial, venous limb diameters and morpho-structural changes (tortuous, cross-linked capillaries) were assessed using NVC.Results: Thirty-four patients with PND and 15 HCs were enrolled in this study. The two groups were matched for age and body mass index (BMI). Patients with PND had higher NPT and NVRI in comparison with HCs [(20 (17-23) vs 14 (14-15), p<0.001), (0.55 (0.51-0.61) vs 0.43 (0.38-0.49), p<0.001), respectively]. A higher proportion of patients with PND had tortuous capillaries than HCs (62% and 20% respectively, p=0.005). The mean NVRI was higher in patients with PND who had tortuous capillaries than patients who did not have tortuous capillaries (0.58 (0.7) and 0.52 (0.09), respectively p=0.033).Conclusion: Microvascular changes can be detected easily using non-invasive methods such as US and NVC. These methods can provide an objective data to better assess PND.
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Goldring, Wushi. "The Griffiths bundle is generated by groups." Mathematische Annalen 375, no. 3-4 (September 9, 2019): 1283–305. http://dx.doi.org/10.1007/s00208-019-01899-0.
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Abstract First the Griffiths line bundle of a $$\mathbf {Q}$$ Q -VHS $${\mathscr {V}}$$ V is generalized to a Griffiths character $${{\,\mathrm{grif}\,}}(\mathbf {G}, \mu ,r)$$ grif ( G , μ , r ) associated to any triple $$(\mathbf {G}, \mu , r)$$ ( G , μ , r ) , where $$\mathbf {G}$$ G is a connected reductive group over an arbitrary field F, $$\mu \in X_*(\mathbf {G})$$ μ ∈ X ∗ ( G ) is a cocharacter (over $$\overline{F}$$ F ¯ ) and $$r:\mathbf {G}\rightarrow GL(V)$$ r : G → G L ( V ) is an F-representation; the classical bundle studied by Griffiths is recovered by taking $$F=\mathbf {Q}$$ F = Q , $$\mathbf {G}$$ G the Mumford–Tate group of $${\mathscr {V}}$$ V , $$r:\mathbf {G}\rightarrow GL(V)$$ r : G → G L ( V ) the tautological representation afforded by a very general fiber and pulling back along the period map the line bundle associated to $${{\,\mathrm{grif}\,}}(\mathbf {G}, \mu , r)$$ grif ( G , μ , r ) . The more general setting also gives rise to the Griffiths bundle in the analogous situation in characteristic p given by a scheme mapping to a stack of $$\mathbf {G}$$ G -Zips. When $$\mathbf {G}$$ G is F-simple, we show that, up to positive multiples, the Griffiths character $${{\,\mathrm{grif}\,}}(\mathbf {G},\mu ,r)$$ grif ( G , μ , r ) (and thus also the Griffiths line bundle) is essentially independent of r with central kernel, and up to some identifications is given explicitly by $$-\mu $$ - μ . As an application, we show that the Griffiths line bundle of a projective $${{\mathbf {G}{\text{- }}{} \mathtt{Zip}}}^{\mu }$$ G - Zip μ -scheme is nef.
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Roth, P. E., B. Kurtz, D. Lo, and U. Storb. "λ 5, but not μ, is required for B cell maturation in a unique γ 2b transgenic mouse line." Journal of Experimental Medicine 181, no. 3 (March 1, 1995): 1059–70. http://dx.doi.org/10.1084/jem.181.3.1059.
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gamma 2b transgenic mice have a severe B cell defect, apparently caused by strong feedback inhibition of endogenous H-gene rearrangement coupled with an inability of gamma 2b to provide the survival/maturation functions of mu. A unique gamma 2b transgenic line, named the C line, was found to permit B cell development. When the C line is crossed with a mu-membrane knockout line, gamma 2b+ B cells develop in the homozygous knockout. In contrast, a transgenic line representative of all the other gamma 2b lines is completely B cell deficient when mu-mem is deleted. Strikingly, the C phenotype is dominant in C x other gamma 2b transgenic line crosses. There is no evidence for higher gamma 2b transgene expression or other position effects on the transgene in the C mouse. The sequences of the three gamma 2b transgene copies in the C line are identical to that of the original transgene. These results have led to the conclusion that in the C line the transgene integration constitutively induces a gene whose expression can replace mu. To more clearly delineate the stage at which the altered phenotype of the C line is expressed, C mice were crossed onto a lambda 5 knockout background. In the absence of lambda 5, the C line produces no B cells. Since it was also found that gamma 2b can associate with the surrogate light chain (sL; lambda 5/Vpre-B), the crosses between C line gamma 2b mice and lambda 5 knockout mice suggest that gamma 2b/sL is required for B cell maturation in this mouse line. Thus, gamma 2b alone is unable to replace mu for pre-B cell survival/maturation; however, in combination with an unknown factor and the sL, gamma 2b can provide these nurturing functions.
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Tisch, R., N. Kondo, and N. Hozumi. "Parameters that govern the regulation of immunoglobulin delta heavy-chain gene expression." Molecular and Cellular Biology 10, no. 10 (October 1990): 5340–48. http://dx.doi.org/10.1128/mcb.10.10.5340.
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The mu and delta immunoglobulin heavy-chain genes comprise a complex transcriptional unit in which a single mRNA precursor gives rise to mu- and delta-specific transcripts. During the immature B-cell stage, posttranscriptional processing events involving alternate splicing and cleavage-polyadenylation site selection give rise to mu- but not delta-encoding transcripts. In terminally differentiated B cells, delta mRNA is not synthesized because of a transcription termination event occurring upstream of the delta-gene locus. In an attempt to gain insight into the respective contributions of alternate splicing and cleavage-polyadenylation in the control of delta mRNA synthesis, we have constructed a set of plasmids in which membrane mu (mu m)-delta intergenic sequences containing the mu m poly(A) site but differing in splicing capacity were inserted in between a VH and delta gene. The mu m-delta insertion vectors were transfected into a B lymphoma line representative of an immature stage, and proximal mu m poly(A) site usage and delta mRNA synthesis were assessed. To determine unequivocally whether the mu m-delta intergenic region can regulate termination, the insertion vectors were also transfected into a B myeloma line, and transcription through the region was measured. In immature B-cell transfectants, splicing site selection was found to have a key role in determining poly(A) site utilization and concomitant delta mRNA expression. Mature delta mRNA synthesis was blocked by an upstream cleavage-polyadenylation event only when the proximal poly(A) site was associated with appropriate splicing signals. Furthermore, in vitro transcription assays revealed that the mu m-delta intergenic region is sufficient to regulate transcription termination within a 1,2430-base-pair region containing the mu m poly(A) site in myeloma transfectants. The mu m-delta insertion vectors provide an excellent model system for studying the regulatory aspects of this transcription termination event.
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Tisch, R., N. Kondo, and N. Hozumi. "Parameters that govern the regulation of immunoglobulin delta heavy-chain gene expression." Molecular and Cellular Biology 10, no. 10 (October 1990): 5340–48. http://dx.doi.org/10.1128/mcb.10.10.5340-5348.1990.
Full textAbstract:
The mu and delta immunoglobulin heavy-chain genes comprise a complex transcriptional unit in which a single mRNA precursor gives rise to mu- and delta-specific transcripts. During the immature B-cell stage, posttranscriptional processing events involving alternate splicing and cleavage-polyadenylation site selection give rise to mu- but not delta-encoding transcripts. In terminally differentiated B cells, delta mRNA is not synthesized because of a transcription termination event occurring upstream of the delta-gene locus. In an attempt to gain insight into the respective contributions of alternate splicing and cleavage-polyadenylation in the control of delta mRNA synthesis, we have constructed a set of plasmids in which membrane mu (mu m)-delta intergenic sequences containing the mu m poly(A) site but differing in splicing capacity were inserted in between a VH and delta gene. The mu m-delta insertion vectors were transfected into a B lymphoma line representative of an immature stage, and proximal mu m poly(A) site usage and delta mRNA synthesis were assessed. To determine unequivocally whether the mu m-delta intergenic region can regulate termination, the insertion vectors were also transfected into a B myeloma line, and transcription through the region was measured. In immature B-cell transfectants, splicing site selection was found to have a key role in determining poly(A) site utilization and concomitant delta mRNA expression. Mature delta mRNA synthesis was blocked by an upstream cleavage-polyadenylation event only when the proximal poly(A) site was associated with appropriate splicing signals. Furthermore, in vitro transcription assays revealed that the mu m-delta intergenic region is sufficient to regulate transcription termination within a 1,2430-base-pair region containing the mu m poly(A) site in myeloma transfectants. The mu m-delta insertion vectors provide an excellent model system for studying the regulatory aspects of this transcription termination event.
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Grosu, Sergio, Johannes Rübenthaler, Thomas Knösel, Matthias Trottmann, Julian Marcon, and Dirk-Andre Clevert. "Splenogonadal fusion evaluation using Contrast Enhanced Ultrasound and Elastography. A case report." Medical Ultrasonography 21, no. 3 (August 31, 2019): 356. http://dx.doi.org/10.11152/mu-1897.
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We present the case of splenogonadal fusion in a 53-year-old male patient assessed by ultrasound and MRI, confirmed by pathologic examination. In addition to B-mode and colour-coded Doppler ultrasound, shear wave elastography and CEUS were performed and are presented in detail. Splenogonadal fusion is a rare congenital anomaly presumably caused by an abnormal attachment of splenic tissue to the gonad during gestation. Diagnosis is challenging for clinicians and in unclear cases splenogonadal fusion might cause unnecessary orchiectomies with benign pathologic results. Ultrasound is the first-line imaging modality in the diagnosis of testicular pathologies. This case report summarizes all available modern ultrasound imagingtechnologies and highlights the possibilities for the diagnosis of splenogonadal fusion.
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Grupp, S. A., R. N. Mitchell, K. L. Schreiber, D. J. McKean, and A. K. Abbas. "Molecular mechanisms that control expression of the B lymphocyte antigen receptor complex." Journal of Experimental Medicine 181, no. 1 (January 1, 1995): 161–68. http://dx.doi.org/10.1084/jem.181.1.161.
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The B cell receptor for antigen (BCR) is a complex of membrane immunoglobulin (mIg) and at least two other proteins, Ig alpha (mb-1) and Ig beta (B29). This complex promotes surface expression of the BCR and acts to transduce an activation signal. We have used a system of mu heavy chain constructs transfected into murine B cell lines to probe structure-function relationships in the BCR complex. One mutant mu chain, in which two polar transmembrane residues (Tyr587, Ser588) are replaced with valine, fails to associate with Ig alpha and Ig beta and is incapable of transducing signals as a result of mIg cross-linking. This mutant is expressed on the surface at high levels when transfected into a plasmacytoma line that lacks Ig alpha, whereas wild-type mu is retained in this cell line in the endoplasmic reticulum. Pulse-chase and immunoprecipitation analyses indicate that the mutant is more rapidly released from calnexin than the wild-type mu. Further, transfection of Ig alpha into this Ig alpha-negative cell line allows release of the mu chain from calnexin and surface expression of the BCR. These results identify the transmembrane residues of mu heavy chain that control binding to calnexin and Ig alpha, and suggest that calnexin-dependent intracellular retention is an important control mechanism for expression of the BCR complex.
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Ruether, J. E., A. Maderious, D. Lavery, J. Logan, S. M. Fu, and S. Chen-Kiang. "Cell-type-specific synthesis of murine immunoglobulin mu RNA from an adenovirus vector." Molecular and Cellular Biology 6, no. 1 (January 1986): 123–33. http://dx.doi.org/10.1128/mcb.6.1.123.
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The mouse immunoglobulin heavy-chain mu constant region gene was cloned into the early region 1B of an adenovirus type 5 vector to allow reproducible kinetics of expression of the mu gene in the presence of continuous host protein synthesis after infection by the recombinant. The immunoglobulin-adenovirus recombinant is helper independent in infecting human fibroblastic and B- and T-cell lines and expresses mu in a cell-type-specific manner. By Northern blot analysis, correctly polyadenylated and spliced E1B-mu S and E1B-mu m mRNAs are found to be equally abundant at steady state in fibroblasts. In contrast, and appropriately, only E1B-mu S mRNAs accumulate in a lambda light-chain-secreting myeloma cell line. Analysis of nascent transcripts pulse labeled in isolated nuclei demonstrates equimolar polymerase loading throughout the mu region in all cell types infected by mu-Ad. Thus, correct polyadenylation and splicing of E1B-mu S and E1B-mu m in fibroblasts does not require transcription termination in the region separating the mu S and mu m polyadenylation sites. Furthermore, differential expression of mu transcripts in the background of myeloma cells is regulated at the level of RNA processing and does not require the presence of the immunoglobulin heavy-chain enhancer or promoter element.
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Ruether, J. E., A. Maderious, D. Lavery, J. Logan, S. M. Fu, and S. Chen-Kiang. "Cell-type-specific synthesis of murine immunoglobulin mu RNA from an adenovirus vector." Molecular and Cellular Biology 6, no. 1 (January 1986): 123–33. http://dx.doi.org/10.1128/mcb.6.1.123-133.1986.
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The mouse immunoglobulin heavy-chain mu constant region gene was cloned into the early region 1B of an adenovirus type 5 vector to allow reproducible kinetics of expression of the mu gene in the presence of continuous host protein synthesis after infection by the recombinant. The immunoglobulin-adenovirus recombinant is helper independent in infecting human fibroblastic and B- and T-cell lines and expresses mu in a cell-type-specific manner. By Northern blot analysis, correctly polyadenylated and spliced E1B-mu S and E1B-mu m mRNAs are found to be equally abundant at steady state in fibroblasts. In contrast, and appropriately, only E1B-mu S mRNAs accumulate in a lambda light-chain-secreting myeloma cell line. Analysis of nascent transcripts pulse labeled in isolated nuclei demonstrates equimolar polymerase loading throughout the mu region in all cell types infected by mu-Ad. Thus, correct polyadenylation and splicing of E1B-mu S and E1B-mu m in fibroblasts does not require transcription termination in the region separating the mu S and mu m polyadenylation sites. Furthermore, differential expression of mu transcripts in the background of myeloma cells is regulated at the level of RNA processing and does not require the presence of the immunoglobulin heavy-chain enhancer or promoter element.
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Hoffmann, Beatrice, Michael Blaivas, Jacques Abramowicz, Michael Bachmann, Radu Badea, Barbara Braden, Vito Cantisani, et al. "Medical Student Ultrasound Education, a WFUMB Position Paper, Part II. A consensus statement of ultrasound societies." Medical Ultrasonography 22, no. 2 (May 11, 2020): 220. http://dx.doi.org/10.11152/mu-2599.
Full textAbstract:
Ultrasound is becoming a fundamental first-line diagnostic tool for most medical specialties and an innovative tool to teach anatomy, physiology and pathophysiology to undergraduate and graduate students. However, availability of structured training programs during medical school is lagging behind and many physicians still acquire all their ultrasound skills during postgraduate training.There is wide variation in medical student ultrasound education worldwide. Sharing successful educational strategies from early adopter medical schools and learning from leading education programs should advance the integration of ultrasound into the university medical school curricula. In this overview, we present current approaches and suggestions by ultrasound societies concerning medical student educa-tion throughout the world. Based on these examples, we formulate a consensus statement with suggestions on how to integrate ultrasound teaching into the preclinical and clinical medical curricula.
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Galluccio, Felice, Tolga Ergonenc, Ece Yamak Altinpulluk, Maria Perez Herrero, Maria del Mar De la Torre Carpente, Marco Capassoni, Karla Espinoza, et al. "Role of point of care ultrasound in COVID-19 pandemic: what lies beyond the horizon?" Medical Ultrasonography 22, no. 4 (November 18, 2020): 461. http://dx.doi.org/10.11152/mu-2614.
Full textAbstract:
The pandemic of COVID-19 requires rapid and easy access to reliable imaging modalities for diagnosis and follow up. Considering the cost-effectiveness of the imaging used, ultrasound is a non-ionizing, portable and bedside imaging modality with a high diagnostic impact in emergencies and intensive care units in pandemics, but it is operator dependent. In our article, we provide a comprehensive review of the role of point-of-care ultrasound in the diagnosis of COVID-19 infection and its impact on the lungs, cardiovascular system, eyes and abdominal organs. Moreover, ultrasound can provide real-time diagnostic and therapeutic interventions, such as the placement of a central catheter and aspiration of pericardial effusion. Awareness of health care professionals in the front-line fighting COVID-19 infection in emergency rooms, clinics, and in intensive care units is important and will help rapid and targeted management decisions.
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Radcliffe, G., Y. C. Lin, M. Julius, K. B. Marcu, and J. Stavnezer. "Structure of germ line immunoglobulin alpha heavy-chain RNA and its location on polysomes." Molecular and Cellular Biology 10, no. 1 (January 1990): 382–86. http://dx.doi.org/10.1128/mcb.10.1.382.
Full textAbstract:
We describe the structure of the major germ line RNA transcribed from unrearranged immunoglobulin alpha heavy-chain genes in immunoglobulin M-expressing cells of the I.29 mu B-cell lymphoma, a cell line capable of switching to immunoglobulin A expression upon lipopolysaccharide treatment. This germ line alpha RNA has a small open reading frame that does not include the C alpha domain, and this RNA appears to be present on polysomes in I.29 mu cells.
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Radcliffe, G., Y. C. Lin, M. Julius, K. B. Marcu, and J. Stavnezer. "Structure of germ line immunoglobulin alpha heavy-chain RNA and its location on polysomes." Molecular and Cellular Biology 10, no. 1 (January 1990): 382–86. http://dx.doi.org/10.1128/mcb.10.1.382-386.1990.
Full textAbstract:
We describe the structure of the major germ line RNA transcribed from unrearranged immunoglobulin alpha heavy-chain genes in immunoglobulin M-expressing cells of the I.29 mu B-cell lymphoma, a cell line capable of switching to immunoglobulin A expression upon lipopolysaccharide treatment. This germ line alpha RNA has a small open reading frame that does not include the C alpha domain, and this RNA appears to be present on polysomes in I.29 mu cells.
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Prestle, J., K. Pfizenmaier, J. Brenner, and F. J. Johannes. "Protein kinase C mu is located at the Golgi compartment." Journal of Cell Biology 134, no. 6 (September 15, 1996): 1401–10. http://dx.doi.org/10.1083/jcb.134.6.1401.
Full textAbstract:
Protein kinase C mu (PKC mu) displays unusual structural features like a pleckstrin homology domain and an amino-terminal hydrophobic region with a putative leader peptide and transmembrane sequence. As a discrete location often is a direct clue to the potential biological function of a kinase, antibodies directed against unique amino- and carboxy-terminal domains of PKC mu were used to localize the protein within intracellular compartments in immunofluorescence and subcellular fractionation studies. Confocal laser scanning microscopy showed colocalization of PKC mu with the resident Golgi marker protein beta 1,4 galactosyltransferase in PKC mu transfectants and in the human hepatocellular carcinoma cell line HepG2, expressing endogenous PKC mu. Long-term treatment of cells with brefeldin A, which disintegrates the Golgi apparatus, disrupted PKC mu-specific staining. Cosegregation of PKC mu with beta 1,4 galactosyltransferase, but not with the endosomal marker rab5, upon density gradient fractionation and Western blot analysis of HepG2 cell extracts, provides independent evidence for a Golgi localization of PKC mu. Moreover, cellular sulfate uptake and Golgi-specific glycosaminoglycan sulfation was enhanced in PKC mu transfectants. Together, these data suggest that PKC mu is a resident protein kinase of the core Golgi compartment and is involved in basal transport processes.
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Sparchez, Zeno, Tudor Mocan, Pompilia Radu, Iuliana Nenu, Mihai Comsa, Nadim Al Hajjar, Emil Mois, Adrian Bartos, Gabriel Kacso, and Mihaela Sparchez. "Microwave ablation in the treatment of liver tumors. A better tool or simply more power?" Medical Ultrasonography 22, no. 4 (November 18, 2020): 451. http://dx.doi.org/10.11152/mu-2556.
Full textAbstract:
It has been a long time since tumor ablation was first tested in patients with liver cancer, especially hepatocellular carcinoma. Since than it has become a first line treatment modality for hepatocellular carcinoma. Over the years, the indications of thermal ablation have expanded to colorectal cancer liver metastases and intrahepatic cholangiocarcinoma as well. Together with the new indication for ablation, new ablation devices have been developed as well. Among them microwave ablation shows potential in replacing radiofrequency ablation as the preferred method of thermal ablation in liver cancer. The debate whether radiofrequency or microwave ablation should be the preferred method of treatment in patients with liver cancer remains open. The main purpose of this review is to offer some answers to the question: Microwave ablation in liver tumors: a better tool or simply more power? Various clinical scenarios will be analyzed including small, medium, and intermediate size hepatocellular carcinoma, colorectal cancer liver metastases and intrahepatic cholangiocarcinoma. Furthermore, the advantages, limitations, and technical considerations of MWA treatment will be provided also.
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Lisch, D., P. Chomet, and M. Freeling. "Genetic characterization of the Mutator system in maize: behavior and regulation of Mu transposons in a minimal line." Genetics 139, no. 4 (April 1, 1995): 1777–96. http://dx.doi.org/10.1093/genetics/139.4.1777.
Full textAbstract:
Abstract Most Mutator lines of maize harbor several different classes of Mu transposons, each of which may be present in high copy number. The regulatory element is also often found in high copy number, and it is this element's behavior that is presumed to cause the non-Mendelian inheritance of Mutator activity. Using a very simple Mutator line, we demonstrate tha MuDR-1, a regulator of the Mutator system, can functionally replace standard non-Mendelian Mutator activity and that MuDR-1 is associated with the loss of methylation of the termini of another Mu transposon. Further, we show that Mu transposons can transpose duplicatively, that reinsertion tends to be into unlinked sites, and that MuDR-1 frequently suffers deletions. Changes in chromosomal position and the mode of sexual transmission are shown to be associated with changes in the frequency of MuDR-1 duplication and with the activity of MuDR-1 as monitored by the excision frequency of a reporter transposon of the Mu family, Mu1. Our data are derived from a Minimal Mutator Line in which there are relatively few Mu transposons, including one MuDR-1 regulator and as few as one Mu1 reporter. The seemingly enigmatic results that have been obtained using more complicated Mu genotypes are reinterpreted using simple Mendelian principles. We have borrowed a gap-repair model from Drosophila biologists to explain both duplications and deletions of MuDR-1.
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Harrington, Kevin C., A. Vishwas, A. Weiß, B. Magnelli, L. Grassitelli, M. Zajaček, E. F. Jiménez-Andrade, et al. "The ‘Red Radio Ring’: ionized and molecular gas in a starburst/active galactic nucleus at z ∼ 2.55." Monthly Notices of the Royal Astronomical Society 488, no. 2 (July 3, 2019): 1489–500. http://dx.doi.org/10.1093/mnras/stz1740.
Full textAbstract:
ABSTRACT We report the detection of the far-infrared (FIR) fine-structure line of singly ionized nitrogen, [N ii] 205 $\mu$m , within the peak epoch of galaxy assembly, from a strongly lensed galaxy, hereafter ‘The Red Radio Ring’; the RRR, at z = 2.55. We combine new observations of the ground-state and mid-J transitions of CO (Jup = 1, 5, 8), and the FIR spectral energy distribution (SED), to explore the multiphase interstellar medium (ISM) properties of the RRR. All line profiles suggest that the H ii regions, traced by [N ii] 205 $\mu$m , and the (diffuse and dense) molecular gas, traced by CO, are cospatial when averaged over kpc-sized regions. Using its mid-IR-to-millimetre (mm) SED, we derive a non-negligible dust attenuation of the [N ii] 205 $\mu$m line emission. Assuming a uniform dust screen approximation results a mean molecular gas column density >1024 cm−2, with a molecular gas-to-dust mass ratio of 100. It is clear that dust attenuation corrections should be accounted for when studying FIR fine-structure lines in such systems. The attenuation corrected ratio of $L_{\rm N\,{\small II}205} / L_{\rm IR(8\!-\!1000\, \mu m)} = 2.7 \times 10^{-4}$ is consistent with the dispersion of local and z > 4 SFGs. We find that the lower limit, [N ii] 205 $\mu$m -based star formation rate (SFR) is less than the IR-derived SFR by a factor of 4. Finally, the dust SED, CO line SED, and $L_{\rm N\,{\small II}205}$ line-to-IR luminosity ratio of the RRR is consistent with a starburst-powered ISM.
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Alleman, Mary, and Michael Freeling. "THE Mu TRANSPOSABLE ELEMENTS OF MAIZE: EVIDENCE FOR TRANSPOSITION AND COPY NUMBER REGULATION DURING DEVELOPMENT." Genetics 112, no. 1 (January 1, 1986): 107–19. http://dx.doi.org/10.1093/genetics/112.1.107.
Full textAbstract:
ABSTRACT The Mu transposon of maize exists in a highly mutagenic strain called Robertson's Mutator. Plants of this strain contain 10-50 copies of the Mu element, whereas most maize strains and other plants have none. When Mutator plants are crossed to plants of the inbred line 1S2P, which does not have copies of Mu, the progeny plants have approximately the same number of Mu sequences as did their Mutator parent. Approximately one-half of these copies have segregated from their parent and one-half have arisen by transposition and are integrated into new positions in the genome. This maintenance of copy number can be accounted for by an extremely high rate of transposition of the Mu elements (10-15 transpositions per gamete per generation). When Mutator plants are self-pollinated, the progeny double their Mu copy number in the first generation, but maintain a constant number of Mu sequences with subsequent self-pollinations. Transposition of Mu and the events that lead to copy number maintenance occur very late in the development of the germ cells but before fertilization. A larger version of the Mu element transposes but is not necessary for transposition of the Mu sequences. The progeny of crosses with a Mutator plant occasionally lack Mutator activity; these strains retain copies of the Mu element, but these elements no longer transpose.
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Mostert, W., D. I. Pullin, R. Samtaney, and V. Wheatley. "Converging cylindrical magnetohydrodynamic shock collapse onto a power-law-varying line current." Journal of Fluid Mechanics 793 (March 16, 2016): 414–43. http://dx.doi.org/10.1017/jfm.2016.138.
Full textAbstract:
We investigate the convergence behaviour of a cylindrical, fast magnetohydrodynamic (MHD) shock wave in a neutrally ionized gas collapsing onto an axial line current that generates a power law in time, azimuthal magnetic field. The analysis is done within the framework of a modified version of ideal MHD for an inviscid, non-dissipative, neutrally ionized compressible gas. The time variation of the magnetic field is tuned such that it approaches zero at the instant that the shock reaches the axis. This configuration is motivated by the desire to produce a finite magnetic field at finite shock radius but a singular gas pressure and temperature at the instant of shock impact. Our main focus is on the variation with shock radius $r$, as $r\rightarrow 0$, of the shock Mach number $M(r)$ and pressure behind the shock $p(r)$ as a function of the magnetic field power-law exponent ${\it\mu}\geqslant 0$, where ${\it\mu}=0$ gives a constant-in-time line current. The flow problem is first formulated using an extension of geometrical shock dynamics (GSD) into the time domain to take account of the time-varying conditions ahead of the converging shock, coupled with appropriate shock-jump conditions for a fast, symmetric MHD shock. This provides a pair of ordinary differential equations describing both $M(r)$ and the time evolution on the shock, as a function of $r$, constrained by a collapse condition required to achieve tuned shock convergence. Asymptotic, analytical results for $M(r)$ and $p(r)$ are obtained over a range of ${\it\mu}$ for general ${\it\gamma}$, and for both small and large $r$. In addition, numerical solutions of the GSD equations are performed over a large range of $r$, for selected parameters using ${\it\gamma}=5/3$. The accuracy of the GSD model is verified for some cases using direct numerical solution of the full, radially symmetric MHD equations using a shock-capturing method. For the GSD solutions, it is found that the physical character of the shock convergence to the axis is a strong function of ${\it\mu}$. For $0\leqslant {\it\mu}<4/13$, $M$ and $p$ both approach unity at shock impact $r=0$ owing to the dominance of the strong magnetic field over the amplifying effects of geometrical convergence. When ${\it\mu}\geqslant 0.816$ (for ${\it\gamma}=5/3$), geometrical convergence is dominant and the shock behaves similarly to a converging gas dynamic shock with singular $M(r)$ and $p(r)$, $r\rightarrow 0$. For $4/13<{\it\mu}\leqslant 0.816$ three distinct regions of $M(r)$ variation are identified. For each of these $p(r)$ is singular at the axis.
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Schneider, J., R. Grosser, K. Jayasimhulu, W. Xue, and D. Warshawsky. "Degradation of Pyrene, Benz[a]anthracene, and Benzo[a]pyrene by Mycobacterium sp. Strain RJGII-135, Isolated from a Former Coal Gasification Site." Applied and Environmental Microbiology 62, no. 4 (April 1996): 1491. http://dx.doi.org/10.1128/aem.62.4.1491-1491d.1996.
Full textAbstract:
Volume 62, no. 1, p. 14, column 1, line 20: "250 (mu)g each of yeast extract, peptone, and soluble starch ml(sup-1)" should read "250 (mu)g each of yeast extract, peptone, and soluble starch liter(sup-1)." [This corrects the article on p. 13 in vol. 62.].
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Tran, Quoc Toan, The Dan Pham, Thanh Duong Nguyen, Van Huyen Luu, Huu Nghi Do, Xuan Duy Le, Phi Hung Nguyen, et al. "Optimization of Murrayafoline A ethanol extraction process from the roots of Glycosmis stenocarpa, and evaluation of its Tumorigenesis inhibition activity on Hep-G2 cells." Open Chemistry 19, no. 1 (January 1, 2021): 830–42. http://dx.doi.org/10.1515/chem-2021-0067.
Full textAbstract:
Abstract Glycosmis stenocarpa is a species of shrub found in the Northern provinces of Vietnam. Its roots contain different carbazolic derivatives, mainly Murrayafoline A (Mu-A), which exhibits valuable biological activities. In this study, we performed an extraction of Mu-A from the roots of G. stenocarpa and optimized this process using response surface methodology (RSM) according to a central composite design, with three independent parameters including extraction time (min), extraction temperature (°C), and solvent/material ratio (mL/g). Two dependent variables were the Mu-A content (mg/g raw materials) and extraction efficiency (%). The optimal conditions to extract Mu-A were found to be as follows: extraction temperature, 67°C; extraction time, 165 min; and solvent/material ratio, 5:1. Under these conditions, the Mu-A content and extraction efficiency were 38.94 ± 1.31 mg/g raw materials and 34.98 ± 1.18%, respectively. Mu-A exhibited antiproliferation and antitumor-promoting activity against the HepG-2 cell line. The present optimization work of Mu-A extraction from G. stenocarpa roots contributed to the attempt of designing a large-scale extraction process for the compound and further exploitation of its potential in vivo applications.
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Brown, J., and V. Sundaresan. "Genetic study of the loss and restoration of Mutator transposon activity in maize: evidence against dominant-negative regulator associated with loss of activity." Genetics 130, no. 4 (April 1, 1992): 889–98. http://dx.doi.org/10.1093/genetics/130.4.889.
Full textAbstract:
Abstract The Mutator system of transposable elements is characterized by a family of transposons called Mu transposons that share common termini and are actively transposing in Robertson's Mutator (Mu) lines of maize. Mu lines lose transposition activity during propagation by either outcrossing or inbreeding. This loss of transposition activity, which can occur at non-Mendelian frequencies, is in the form of loss of forward transposition activity resulting in a decrease in the generation of new mutations, as well as the loss of mutability of Mu transposon induced mutations, and it has been correlated with hypermethylation of the Mu elements. Previous studies have concluded that restoration of Mutator transposon activity by crossing inactive lines back to active lines is incomplete or transient, and depends upon the sex of the inactive parent. Further, it has been proposed that the inactive system is dominant to the active system, with the dominance possibly mediated through a negative regulatory factor that is preferentially transmitted through the female. In this study, we have examined the frequencies of loss and restoration of Mu transposon activity using a Mu line carrying an insertion in the bronze 1 locus. We find that transmission of Mu transposon activity to non-Mu plants can occur at high rates through males and females, but individual cases of decreased transmission through the male were observed. We also find that in crosses between inactive-Mu and active-Mu plants, reactivation was efficient as well as heritable, regardless of the sex of the inactive parent. Similar results were obtained whether the inactivation occurred in an outcross or a self. In all cases examined, loss of Mu transposon activity was correlated with hypermethylation of Mu elements, and reactivation was correlated with their demethylation. Our results indicate that an inactive Mu system does not exhibit dominance over an active Mu system. We conclude that contrary to current models, inactivation and its maintenance is not obligatorily associated with a dominant negative regulatory factor whether nuclear or cytoplasmic, and we propose a revised model to account for these and other observations.
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Pourtaghi, Ladan Badiee, Farahnaz Bineshian, Bizhan Sadighi Moghadam, Raheb Ghorbani, and Hossein Nazari. "Anti-Proliferative and Apoptotic Activity of Rumex obtusifolius seed’s Hydroalcoholicextract on Human Colon Cancer Cell Line “SW480”." Journal of Molecular Biology Research 9, no. 1 (October 23, 2019): 111. http://dx.doi.org/10.5539/jmbr.v9n1p111.
Full textAbstract:
Cancer is considered a serious threat to human health thatcolon cancer is the third most common cancer in the world. Colon cancer has undergone significant growth worldwide in recent years, and many people die every year as a result of this disease, which its treatment is a major challenge for researchers. In this study, we investigated the effect of anti-proliferative and apoptotic activity seed’s hydroalcoholic extract of Rumex obtusifolius, “is native to Semnan's northern region” on the human colon cancer cell line, SW480.
The SW480 human colon cancer cell line were cultured in RPMI 1640 cell culture containing 10% Fetal bovine Serum and 1% Penicillin and Streptomycin antibiotics and incubated with a relative humidity of 95%, carbon dioxide 5% at 37°C. The SW480 cancer cell line was cultured in 48 and 96 well plates and treated with different concentrations of seeds hydroalcoholic extract of Rumex obtusifolius (20/40/80/160/320 micrograms/ml) for evaluation of cell viability by Trypan blue exclusion method and MTT assay. A non-treated group was used as control and a treated group with DMSO was used as solvent in solution of powdered extract as vehicle as well as positive control groups. Also, cell apoptosis assessment was performed by Propideum iodide/Annexin V test “Flowcytometry”and DNA fragmentation analysis “Agaros electrophoresis”.
Seed hydroalcoholic extract caused cell death at concentrations of 40, 80, 160 and 320μg/ml, which the anticancer effect trend to increase significantly from 80μg/ml. The effect of R. obtusifolius seed extract even has more anti-cancer effect in 160 and 320μg/ml than cells which is treated to 5FU as a positive control groups.
Seed hydroalcoholic extract reduced cell viability in proportion concentration. The effect of anticancer activity of seed extract trend to increase from 40μg/ml but it was shown effective concentrations for inhibiting of the cells growth were 160, 320μg/ml in 48 hr incubation time and 80, 160 and 320μg/ml in 72 hr incubation time. Also, the effect of this extract at concentrations of 160 and 320μg/ml with control group is not significant which have more cytotoxicity and even extract can have a significant effect on decreasing the survival of the SW480 cells. The data generated by flow cytometry are shown that colon cancer cells trend to necrosis and apoptotic pathway from 40μg/ml and increased significantly entrance to apoptotic pathway from 80μg/ml which is confirm the Trypan blue and MTT assay tests. Since the appearance of the DNA fragmentation, which precedes the bioavailability change, is characteristic to apoptosis, the extracts were considered to be apoptosis-inducers. The ability to inhibit growth and induction of apoptosis in SW480 cancer cells is a concentration- and time dependent manner. These results indicated that the induction of apoptosis at least partly mediates their cytotoxic activity which is necessary down further study for elucidation apoptotic signaling pathway.
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Kitchingman, GR, U. Rovigatti, AM Mauer, S. Melvin, SB Murphy, and S. Stass. "Rearrangement of immunoglobulin heavy chain genes in T cell acute lymphoblastic leukemia." Blood 65, no. 3 (March 1, 1985): 725–29. http://dx.doi.org/10.1182/blood.v65.3.725.725.
Full textAbstract:
Abstract We studied the arrangement of the immunoglobulin heavy chain genes by Southern blot analysis of DNA freshly obtained from marrow blast cells of 14 children with T cell acute lymphoblastic leukemia (T-ALL) using probes to the C mu and JH gene segments: At least one of the C mu-gene alleles was rearranged in three cases. In two of these, one C mu gene had the germ-line configuration and one was rearranged, whereas both alleles were rearranged in the third case. In one case, a rearranged heavy chain gene hybridized to the C mu-region probe, but not to the JH probe, indicating that the entire JH region had been deleted. These results demonstrate that immunoglobulin heavy chain gene rearrangements are not restricted to B lineage lymphoproliferative diseases in humans.
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Kitchingman, GR, U. Rovigatti, AM Mauer, S. Melvin, SB Murphy, and S. Stass. "Rearrangement of immunoglobulin heavy chain genes in T cell acute lymphoblastic leukemia." Blood 65, no. 3 (March 1, 1985): 725–29. http://dx.doi.org/10.1182/blood.v65.3.725.bloodjournal653725.
Full textAbstract:
We studied the arrangement of the immunoglobulin heavy chain genes by Southern blot analysis of DNA freshly obtained from marrow blast cells of 14 children with T cell acute lymphoblastic leukemia (T-ALL) using probes to the C mu and JH gene segments: At least one of the C mu-gene alleles was rearranged in three cases. In two of these, one C mu gene had the germ-line configuration and one was rearranged, whereas both alleles were rearranged in the third case. In one case, a rearranged heavy chain gene hybridized to the C mu-region probe, but not to the JH probe, indicating that the entire JH region had been deleted. These results demonstrate that immunoglobulin heavy chain gene rearrangements are not restricted to B lineage lymphoproliferative diseases in humans.
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Fowler, John E., Gary J. Muehlbauer, and Michael Freeling. "Mosaic Analysis of the Liguleless3 Mutant Phenotype in Maize by Coordinate Suppression of Mutator-insertion Alleles." Genetics 143, no. 1 (May 1, 1996): 489–503. http://dx.doi.org/10.1093/genetics/143.1.489.
Full textAbstract:
Abstract Ligubless3-O (Lg3-O) transforms the leaf blade, auricle and ligule into sheath around the midrib region. We conducted a genetic mosaic analysis of the Lg3 phenotype to determine the site of Lg3 gene action. Combining the Mutator (Mu) suppressible Lg3-Or211 and al-mum2 alleles in a Mu-active background generated a stock wherein somatic loss of Mu activity resulted in anthocyanin-marked clonal sectors expressing Lg3 in the leaf. Lg3-Or211 plants appear wild type in a Mu-active line, but Mu-inactive plants express a severe Lg3 phenotype. We observed four sector classes: wild type, sheath-like with ligule displacement, sheath-like with ectopic ligule, and auricle-like. The mutation does not cause transformation to a specific cell or regional identity. Lg3-Or211 activity in the mesophyll alters wild-type epidermal cell fates; activity in epidermis seems funtionless. Lg3 mutant activity has a nonautonomous, cell-layer-specific function in the transverse dimension. In the lateral dimension, sectors of Lg3 mutant phenotype can exhibit either cell-autonomous or nonautonomous effects. Our work demonstrates that mosaic analysis by coordinate suppression of Mu-induced alleles is useful for analyzing the cell autonomy of genetically defined functions.
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Kim, Sangchoon. "Efficient Transmit Antenna Subset Selection for Multiuser Space–Time Line Code Systems." Sensors 21, no. 8 (April 11, 2021): 2690. http://dx.doi.org/10.3390/s21082690.
Full textAbstract:
We consider the problem of the efficient transmit antenna subset (TAS) selection for maximizing the signal-to-interference-plus-noise ratio (SINR) of multiuser space–time line code (MU–STLC) systems. The exhaustive search for optimal TAS selection is impractical since the total number of transmit antennas increases. We propose two efficient TAS selection schemes based on the Woodbury formula. The first is to incrementally select NS active transmit antennas among the available NT transmit antennas. To reduce the complexity of the incremental selection scheme, the Woodbury formula is employed in the optimization process. The second is to perform the decremental strategy in which the Woodbury formula is also applied to develop the low-complexity TAS selection procedure for the MU–STLC systems. Simulation results show that the proposed incremental and decremental TAS selection algorithms offer better alternatives than the existing greedy TAS selection algorithm for the MU–STLC systems. Furthermore, in terms of bit error rate, the proposed minimum mean square error decremental TAS selection algorithm turns out to outperform the existing greedy algorithm with significantly lower computational complexity. Finally, we analyze the detection SINR penalty experienced from TAS selection and the analytical quantity is shown to be well matched with simulation results.
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Kondagunta, G. V., G. R. Hudes, R. Figlin, G. Wilding, S. Hariharan, S. N. Kempin, R. Fayyad, S. Hoosen, and R. J. Motzer. "Sunitinib malate (SU) plus interferon (IFN) in first line metastatic renal cell cancer (mRCC): Results of a dose-finding study." Journal of Clinical Oncology 25, no. 18_suppl (June 20, 2007): 5101. http://dx.doi.org/10.1200/jco.2007.25.18_suppl.5101.
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5101 Background: Sunitinib malate is an oral, multitargeted tyrosine kinase inhibitor of VEGFRs and PDGFRs with anti-tumor activity in mRCC patients previously treated with cytokines (JAMA, 2006;295:2516). A phase 3 randomized trial showed superiority for SU over IFN in first-line mRCC (PROC ASCO 24,18S, 2006). Dose and safety for SU combined with IFN was investigated in this phase I trial. Methods: Patients (pts) with previously untreated clear-cell mRCC received SU in repeated 6-week cycles of 50 or 37.5 mg/day orally for 4 weeks, followed by 2 weeks off treatment. IFN was given continuously, starting at 3 MU SC 3x/week with intrapatient dose escalation weekly as tolerated, to a maximum of 9 MU. Pts not tolerating a dose combination received lower doses of SU or IFN, or had dose interruptions. Doses of SU plus IFN were considered tolerable if = 4/6 pts completed 2 cycles without dose reduction or interruption. Results: 25 pts were enrolled; 19 are evaluable for safety/response. 6 pts who started treatment at 37.5 SU and 3 MU IFN are too early. The median age of the 19 pts (16 M: 3 F) was 63 years (range 45–77). MSKCC risk group (JCO 20:289–96, 2002) was 37% good and 63% intermediate. 12 pts started treatment with SU 50 mg and dose escalated IFN to 6 or 9 MU TIW. 13 pts started treatment with SU 37.5 mg and dose escalated IFN at 3 MU or to 6 MU TIW. 4 of 19 pts tolerated two cycles. 68% of pts had dose interruptions of SU; 90% of pts had dose interruptions of IFN. 15/19 pts had grade 3 toxicity, 1 pt had grade 4 hypertension and 1 pt grade 5 toxicity (myocardial infarction). Most common grade 3 toxicities were neutropenia (26%), fatigue (26%), and hand-foot syndrome (16%). Although response was not a primary endpoint, at a median of 3 cycles, there were 2 PR, 14 SD, 2 PD and 1 pt was not evaluable. Conclusions: The adverse events seen with combination SU and IFN in mRCC, neutropenia and fatigue, were similar to those seen with single agent SU and IFN, and resulted in frequent dose modifications and interruptions. The safety and efficacy of 37.5 mg sunitinib and 3 MU IFN is being evaluated. No significant financial relationships to disclose.
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Wagg, J., M. Aravena, D. Brisbin, I. Valtchanov, C. Carilli, E. Daddi, H. Dannerbauer, et al. "Observations of [OI]63 μm line emission in main-sequence galaxies at z ∼ 1.5." Monthly Notices of the Royal Astronomical Society 499, no. 2 (September 19, 2020): 1788–94. http://dx.doi.org/10.1093/mnras/staa2884.
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ABSTRACT We present Herschel–PACS spectroscopy of four main-sequence star-forming galaxies at z ∼ 1.5. We detect [OI]63 μm line emission in BzK-21000 at z = 1.5213, and measure a line luminosity, $L_{\rm [O\, {\small I}]63\, \mu m} = (3.9\pm 0.7)\times 10^9$ L⊙. Our PDR modelling of the interstellar medium in BzK-21000 suggests a UV radiation field strength, G ∼ 320G0, and gas density, n ∼ 1800 cm−3, consistent with previous LVG modelling of the molecular CO line excitation. The other three targets in our sample are individually undetected in these data, and we perform a spectral stacking analysis which yields a detection of their average emission and an [O i]63 μm line luminosity, $L_{\rm [O\, {\small I}]63\, \mu m} = (1.1\pm 0.2)\times 10^9$ L⊙. We find that the implied luminosity ratio, $L_{\rm [O\, {\small I}]63\, \mu m}/L_{\rm IR}$, of the undetected BzK-selected star-forming galaxies broadly agrees with that of low-redshift star-forming galaxies, while BzK-21000 has a similar ratio to that of a dusty star-forming galaxy at z ∼ 6. The high [O i]63 μm line luminosities observed in BzK-21000 and the z ∼ 1−3 dusty and sub-mm luminous star-forming galaxies may be associated with extended reservoirs of low density, cool neutral gas.
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Oancea, A. E., M. Berru, and M. J. Shulman. "Expression of the (recombinant) endogenous immunoglobulin heavy-chain locus requires the intronic matrix attachment regions." Molecular and Cellular Biology 17, no. 5 (May 1997): 2658–68. http://dx.doi.org/10.1128/mcb.17.5.2658.
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The elements which regulate gene expression have traditionally been identified by their effects on reporter genes which have been transfected into cell lines or animals. It is generally assumed that these elements have a comparable role in expression of the corresponding endogenous locus. Nevertheless, several studies of immunoglobulin heavy-chain (IgH) gene expression have reported that the requirements for expressing IgH-derived transgenes differ from the requirements for expression of the endogenous IgH locus. Thus, although expression of transgenes requires multiple elements from the J(H)-C mu intron--the E mu core enhancer, the matrix attachment regions (MARs) which flank E mu, and several switch-associated elements--B-cell lines in which expression of the endogenous heavy-chain gene is maintained at the normal level in the absence of these intronic elements have occasionally been reported. Gene targeting offers an alternative method for assessing regulatory elements, one in which the role of defined segments of endogenous genes can be evaluated in situ. We have applied this approach to the IgH locus of a hybridoma cell line, generating recombinants which bear predetermined modifications in the functional, endogenous mu heavy-chain gene. Our analysis indicates the following. (i) Ninety-eight percent of the expression of the recombinant endogenous mu gene depends on elements in the MAR-E mu-MAR segment. (ii) Expression of the recombinant mu gene depends strongly on the MARs of the J(H)-C mu intron but not on the adjoining E mu core enhancer and switch regions; because our recombinant cell lines bear only a single copy of the mu gene, our results indicate that mu expression is activated by MAR elements lying within that same mu transcription unit. (iii) The MAR segment includes at least one activating element in addition to those defined previously by the binding of presumptive activating proteins in the nuclear matrix. (iv) Close association of the MARs with the E mu enhancer is not required for MAR-stimulated expression. (v) The other MARs in the IgH locus do not in their normal context provide the requisite MAR function.
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Badea, Radu, Ciprian Lucan, Mihai Suciu, Tudor Vasile, and Mirela Gersak. "Contrast enhanced harmonic ultrasonography for the evaluation of acute scrotal pathology. A pictorial essay." Medical Ultrasonography 18, no. 1 (March 1, 2016): 110. http://dx.doi.org/10.11152/mu.2013.2066.181.esy.
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Conventional ultrasonographic evaluation (grey scale and Doppler) represents the first line investigation in the acute pathology of the scrotum. Its diagnosis value in acute scrotal pathology is undoubted in regard with hypervascular lesions, but in the evaluation of isoechoic and hypo/avascular lesions i.v. contrast-enhanced harmonic ultrasonography (CEUS) is recommended in establishing a firm and certain diagnosis. Besides these, CEUS has an important role in the evaluation of the remaining viable testicular tissue in cases of testicular trauma, thus guiding a limited excision surgery. This paper aims to discuss the added diagnosis value of CEUS and to illustrate this through various ultrasonographic images suggestive for acute scrotum pathology.
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Katz, Harley, Thomas P. Galligan, Taysun Kimm, Joakim Rosdahl, Martin G. Haehnelt, Jeremy Blaizot, Julien Devriendt, Adrianne Slyz, Nicolas Laporte, and Richard Ellis. "Probing cosmic dawn with emission lines: predicting infrared and nebular line emission for ALMA and JWST." Monthly Notices of the Royal Astronomical Society 487, no. 4 (June 19, 2019): 5902–21. http://dx.doi.org/10.1093/mnras/stz1672.
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ABSTRACT Infrared and nebular lines provide some of our best probes of the physics regulating the properties of the interstellar medium (ISM) at high redshift. However, interpreting the physical conditions of high-redshift galaxies directly from emission lines remains complicated due to inhomogeneities in temperature, density, metallicity, ionization parameter, and spectral hardness. We present a new suite of cosmological, radiation-hydrodynamics simulations, each centred on a massive Lyman-break galaxy that resolves such properties in an inhomogeneous ISM. Many of the simulated systems exhibit transient but well-defined gaseous discs that appear as velocity gradients in [C ii] 157.6 $\mu$m emission. Spatial and spectral offsets between [C ii] 157.6 $\mu$m and [O iii] 88.33 $\mu$m are common, but not ubiquitous, as each line probes a different phase of the ISM. These systems fall on the local [C ii]–SFR relation, consistent with newer observations that question previously observed [C ii] 157.6 $\mu$m deficits. Our galaxies are consistent with the nebular line properties of observed z ∼ 2–3 galaxies and reproduce offsets on the BPT and mass-excitation diagrams compared to local galaxies due to higher star formation rate (SFR), excitation, and specific-SFR, as well as harder spectra from young, metal-poor binaries. We predict that local calibrations between H α and [O ii] 3727$\, \mathring{\rm A}$ luminosity and galaxy SFR apply up to z > 10, as do the local relations between certain strong line diagnostics (R23 and [O iii] 5007$\, \mathring{\rm A}$/H β) and galaxy metallicity. Our new simulations are well suited to interpret the observations of line emission from current (ALMA and HST) and upcoming facilities (JWST and ngVLA).
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Yang, C. Y., and C. L. Meng. "Regulation of PG Synthase by EGF and PDGF in Human Oral, Breast, Stomach, and Fibrosarcoma Cancer Cell Lines." Journal of Dental Research 73, no. 8 (August 1994): 1407–15. http://dx.doi.org/10.1177/00220345940730080301.
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Prostaglandins may inhibit or promote tumor cell replication, depending on the cell system that is investigated. In our laboratory, we have established and characterized four different specific human cancer cell lines. The objectives of this study were to examine and compare the prostaglandin endoperoxide synthase (PG synthase, EC 1.14.99.1) activity of these cell lines by measuring the conversion of arachidonate to 3H-PGE2 and 3H-PGF2α. We found that the oral epidermal carcinoma cell line (OEC-M1) had a moderate degree of PG synthase activity. Enzyme activity could be partially blocked (statistically significant) by the addition of epidermal growth factor (EGF) at 20 ng/mL and almost completely inhibited by platelet-derived growth factor at (PDGF) 20 mU/mL. By contrast, we discovered that the human breast adenocarcinama cell line (BC-M1) did not contain significant PG synthase, and enzyme activity could be significantly activated by the addition of epidermal growth factor at 20 ng/mL and platelet-derived growth factor at 20 mU/mL. We also found that the human stomach adenocarcinoma cell line (SCM-1) had a significant amount of PG synthase activity, and these PG synthase activities were not activated or inhibited by EGF at 20 ng/mL or PDGF at 20 mU/mL. Furthermore, the human fibrosarcoma (FS-Ml) cell line also contained a moderate degree of PG synthase activity, which could be significantly inhibited by PDGF at 20 mU/mL but was not inhibited by EGF at 20 ng/mL. The results suggest that EGF and PDGF may be involved in the regulation of the PG synthase activities of human oral, breast, stomach, and fibrosarcoma cancer cells.
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Lübke, Katrin T., Charlotte Sachse, Matthias Hoenen, and Bettina M. Pause. "Mu-Suppression as an Indicator of Empathic Processes in Lesbian, Gay, and Heterosexual Adults." Archives of Sexual Behavior 49, no. 2 (October 10, 2019): 635–44. http://dx.doi.org/10.1007/s10508-019-01491-2.
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Abstract Self-reported empathy differs with gender and sexual orientation. The current study investigated whether mu-suppression, reflecting brain activity especially related to state empathy, also is modulated by gender and sexual orientation. Pictures of painful and non-painful actions were presented to 20 lesbians, 20 gay men, 20 heterosexual men and 20 heterosexual women, while EEG was recorded. Individual peak frequencies of mu-activity (electrodes C3, C4) were detected within the 6–11 Hz band for each participant, and mu-suppression indices were calculated. Further, verbal indicators of state empathy (pain ratings) and compassion were assessed. Only heterosexual individuals showed the typical pattern of enhanced mu-suppression in response to painful relative to non-painful pictures. Lesbian women and gay men did not show a differential mu-response. Moreover, they felt less compassion compared to heterosexual individuals. In line with this finding, the more compassion the participants reported, the stronger the mu-suppression in response to painful relative to non-painful pictures was. Pain ratings did not vary with sexual orientation. The lesser compassion reported by lesbian women and gay men is discussed as a mediator of their non-differential mu-suppression response. It is hypothesized that this pattern might relate to gay men and lesbian women tending to perceive the anonymous depicted actors as outgroup members, hence showing less compassion and reduced mu-suppression. As empathy is often related to negative feelings (empathic stress), a clear distinction between individuals to empathize with versus individuals not to emphasize with may well be an adaptive feature in same-sex oriented individuals.
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Zhao, Bo, Nai-Chung Kuo, Ali M. Niknejad, and Borivoje Nikolic. "A Line-Array Technique for Wireless Power Transfer Toward a 100 $\mu$ m $\times100$ $\mu$ m Coil Antenna." IEEE Transactions on Microwave Theory and Techniques 68, no. 1 (January 2020): 353–64. http://dx.doi.org/10.1109/tmtt.2019.2940016.
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MELLOR, BLAKE. "FINITE TYPE LINK HOMOTOPY INVARIANTS II: Milnor's $\bar\mu$-Invariants." Journal of Knot Theory and Its Ramifications 09, no. 06 (September 2000): 735–58. http://dx.doi.org/10.1142/s0218216500000426.
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We define a notion of finite type invariants for links with a fixed linking matrix. We show that Milnor's link homotopy invariant [Formula: see text] is a finite type invariant, of type 1, in this sense. We also generalize this approach to Milnor's higher order [Formula: see text] invariants and show that they are also, in a sense, of finite type. Finally, we compare our approach to another approach for defining finite type invariants within linking classes.
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Gurtu, Sunil. "MU receptor-serotonin link in opioid induced hyperactivity in mice." Life Sciences 46, no. 21 (January 1990): 1539–44. http://dx.doi.org/10.1016/0024-3205(90)90427-s.
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Planckaert, F., and V. Walbot. "Molecular and genetic characterization of Mu transposable elements in Zea mays: behavior in callus culture and regenerated plants." Genetics 123, no. 3 (November 1, 1989): 567–78. http://dx.doi.org/10.1093/genetics/123.3.567.
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Abstract Active Mutator lines of maize (Zea mays L.) have a high mutation rate and contain multiple hypomethylated 1.4-kb and 1.7-kb Mu transposable elements. Correlated with the inactivation of the Mutator system, these Mu elements cease to transpose and become more methylated. To determine whether the shock of tissue culture can affect Mutator activities, F1 progenies of outcrosses between active or inactive Mutator stocks and inbred line A188 were used to initiate embryogenic callus cultures. HinfI restriction digestion of genomic DNA isolated from 3-5-month-old cultures demonstrated that there is a very good correlation between the modification state of Mu elements in the cultures and the Mutator parent. Despite the dedifferentiation and rapid proliferation characteristic of tissue culture, the Mutator activity state is relatively stable during an extended tissue culture period. Cultures established from inactive Mutator lines were not reactivated; cultures established from active lines maintained a high Mu copy number, and most Mu elements remained unmodified. In contrast, weakly active Mutator parents gave rise to cultures in which Mu element modification could switch between low and high methylation during the culture period. Evidence for transposition was investigated with EcoRI digestion of genomic DNA isolated at different times during culture. The appearance of novel Mu-hybridizing fragments and a strong background hybridization are interpreted as evidence that transposition events occur during culture. Plants regenerated from such active cultures transmitted Mutator activity to their progeny.