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41.
Gambarino S Costa C Astegiano S Piasentin EA Segoloni GP Cavallo R Bergallo M 《Molecular biotechnology》2011,49(2):151-158
Polyomavirus BK latently persist in different sites, including the renourinary tract, and may reactivate causing nephropathy
in renal transplant recipients or hemorrhagic cystitis in bone marrow recipients. Based on the sequence of the VP1 gene, four
genotypes have been described, corresponding to the four serologically differentiated subtypes I–IV, with different prevalence
and geographic distribution. In this study, the development and clinical validation of four different Real-Time PCR assays
for the detection and discrimination of BKV genotypes as a substitute of DNA sequencing are described. 379 BK VP1 sequences,
belonging to the main four genotypes, were aligned and “hot spots” of mutation specific for all the strains or isolates were
identified. Specific primers and probes for the detection and discrimination of each genotype by four Real-Time PCR assays
were designed and technically validated. Subsequently, the four Real-Time PCR assays were used to test 20 BK-positive urine
specimens from renal transplant patients, and evidenced a prevalence of BK genotype I, as previously reported in Europe. Results
were confirmed by sequencing. The availability of a rapid and simple genotyping method could be useful for the evaluation
of BK genotypes prevalence and studies on the impact of the infecting genotype on viral biological behavior, pathogenic role,
and immune evasion strategies. 相似文献
42.
The methods of molecular dynamics and correlation functions of coordinates were applied to investigate molecular oscillations in water solution at a variation of the amplitude of fluctuations. It was established, that the amplitude of fluctuation exceeds the threshold value (in water of the order of 0.3-0.45 A), of the force of friction sharply increases, and the vibration mode changes to the mode of limited diffusion. The consistency of the results with the theory of M?ssbauer effect and the model of Brownian oscillator for conformational mobility in biopolymers is discussed. 相似文献
43.
Chiara V. Segré Silvia Senese Sara Loponte Stefano Santaguida Paolo Soffientini Gabriela Grigorean 《MABS-AUSTIN》2016,8(1):37-42
Histone deacetylases (HDACs) are modification enzymes that regulate a plethora of biological processes. HDAC1, a crucial epigenetic modifier, is deregulated in cancer and subjected to a variety of post-translational modifications. Here, we describe the generation of a new monoclonal antibody that specifically recognizes a novel highly dynamic prophase phosphorylation of serine 406-HDAC1, providing a powerful tool for detecting early mitotic cells. 相似文献
44.
45.
ICAMs Are Not Obligatory for Functional Immune Synapses between Naive CD4 T Cells and Lymph Node DCs
46.
Effects of adults body size and larvae diet on the fecundity and percent fertility of eggs laid by Xylotrechus arvicola (Coleoptera: Cerambycidae) females,insect pest in Spanish vineyards 下载免费PDF全文
Álvaro Rodríguez‐González Horacio J. Peláez Óscar González‐López Sara Mayo Pedro A. Casquero 《Entomological Research》2018,48(2):83-91
Xylotrechus arvicola is a pest of grape in some vine‐producing regions of the Iberian Peninsula. Biological parameters and relationships (fecundity and percent fertility of eggs in relationship to body size) of females obtained in the laboratory and captured in vineyards were studied. In laboratory conditions, the mean developmental time of larvae ranged from 384 to 392 days and pupal stage varied between 12 to 14 days. Body size (BS) of X. arvicola females was significantly bigger than males. Fecundity was greater in the laboratory (147 eggs) than in the field (50 eggs) females, but the percent fertility of the laboratory eggs was lower (16 eggs). Laboratory females showed a bigger relationship between the production of eggs and BS than females captured in vineyards. Wild females (PDO Ribera del Duero and Tierra de León) had a positive relationship between the percent fertility of eggs and the BS. No correlation between the percent fertility of eggs and the BS was displayed by females captured in PDO Toro, but these females had a higher percent fertility (53 eggs) than the others PDO's. These biological parameters and relationships studied suggest that the artificial diet may lack certain essential nutrients that vine varieties can provide that favor the fertility of eggs. This explains why wild females have the potential to become a problem pest in the Tempranillo grape variety, with bilateral cordon and bush vines training systems that have the highest incidence of this cerambycid. 相似文献
47.
In 2002, severe acute respiratory syndrome (SARS)-coronavirus (CoV) appeared as a novel human virus with high similarity to bat coronaviruses. However, while SARS-CoV uses the human angiotensin-converting enzyme 2 (ACE2) receptor for cellular entry, no coronavirus isolated from bats appears to use ACE2. Here we show that signatures of recurrent positive selection in the bat ACE2 gene map almost perfectly to known SARS-CoV interaction surfaces. Our data indicate that ACE2 utilization preceded the emergence of SARS-CoV-like viruses from bats. 相似文献
48.
49.
Emilien Loeuillard Haquima El Mourabit Lin Lei Sara Lemoinne Chantal Housset Axelle Cadoret 《生物化学与生物物理学报:疾病的分子基础》2018,1864(12):3688-3696
Portal myofibroblasts (PMF) form a sub-population of highly proliferative and proangiogenic liver myofibroblasts that derive from portal mesenchymal progenitors. Endoplasmic reticulum (ER) stress was previously shown to modulate fibrogenesis, notably in the liver. Our aim was to determine if ER stress occurred in PMF and affected their functions. PMF were obtained after their expansion in vivo from bile duct-ligated (BDL) rats and referred to as BDL PMF. Compared to standard PMF obtained from normal rats, BDL PMF were more myofibroblastic, as assessed by higher alpha-smooth muscle actin expression and collagen 1 production. Their proangiogenic properties were also higher, whereas their proliferative and migratory capacities were lower. CHOP expression was detected in the liver of BDL rats, at the leading edge of portal fibrosis where PMF accumulate. BDL PMF displayed ER dilatation and an overexpression of the PERK pathway downstream targets, Chop, Gadd34 and Trb3, in comparison with standard PMF. In vitro, the induction of ER stress by tunicamycin in standard PMF, caused a decrease in their proliferative and migratory activity, and an increase in their proangiogenic activity, without affecting their myofibroblastic differentiation. Conversely, the treatment of BDL PMF with the PERK inhibitor GSK2656157 reduced ER stress, which caused a decrease in their angiogenic properties, and restored their proliferative and migratory capacity. In conclusion, PMF develop ER stress as they expand with the progression of fibrosis, which further increases their proangiogenic activity, but also inhibits their proliferation and migration. This phenotypic switch may restrict PMF expansion while they support angiogenesis. 相似文献
50.
Sara S. Tynan Niels H. Andersen Max T. Wills Laurence A. Harker Stephen R. Hanson 《Prostaglandins & other lipid mediators》1984,27(5):683-696
The ω-chain variant analogs of prostacyclin (PGI2) and PGD2 in which the n-amyl side-chain has been replaced by a cyclohexyl group have been prepared and their cardiovascular activities have been compared to those of BW-245C(Fig. 1)(1) a potent anti-aggregatory vasodilator bearing a cyclohexyl-terminated side-chain on a hydantoin skeleton. The cyclohexyl group has little effect on PGI2, but converts PGD2 to a long lasting hypotensive agent and increases the platelet anti-aggregatory potency of PGD2 by a factor of 8. The prostaglandin antagonist N-0164 selectively blocks the anti-aggregatory actions of PGD2, cyclohexyl-PGD2, and BW-245C; with essentially no effect on PGI2, cyclohexyl-PGI2 and PGE2 at comparably effective doses. The latter observation is contrary to an earlier report by MacIntyre (2,3), but supports the view that the anti-aggregatory effect of high doses of PGE2 () is mediated by the PGI2 receptor (4). The hydantoin acts at the platelet PGD2 receptor. 相似文献