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1.
A case of systemic mycosis due to a Rhizopus sp. infection is described in a dead-stranded, 10-yr-old, male harbor porpoise (Phocoena phocoena) found on the beach of Neustadt, Schleswig-Holstein on the Baltic Sea (Germany). At necropsy, granulomatous mycotic lesions in brain, lung, kidneys, testis, and draining lymph nodes were found. In addition, a focal ulcerative gastritis of the first stomach, due to a nematode infection, was present and is suspected to be the portal of entry for the fungus.  相似文献   
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Nitric oxide (NO) plays a significant role in the development of diabetic nephropathy. We investigated the effects of an antioxidant, carnosine, on streptozotocin (STZ)-induced renal injury in diabetic rats. We used four groups of eight rats: group 1, control; group 2, carnosine treated; group 3, untreated diabetic; group 4, carnosine treated diabetic. Kidneys were removed and processed, and sections were stained with periodic acid-Schiff (PAS) and subjected to eNOS immunohistochemistry. Examination by light microscopy revealed degenerated glomeruli, thickened basement membrane and glycogen accumulation in the tubules of diabetic kidneys. Carnosine treatment prevented the renal morphological damage caused by diabetes. Moreover, administration of carnosine decreased somewhat the oxidative damage of diabetic nephropathy. Appropriate doses of carnosine might be a useful therapeutic option to reduce oxidative stress and associated renal injury in diabetes mellitus.  相似文献   
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In a seminal study, Dawson and Ehleringer used deuterium measurements on water to show that boxelder (Acer negundo) and bigtooth maple (Acer grandidentatum) trees growing directly next to a perennial stream in a mountain meadow did not use the stream water for transpiration, nor could they identify any other potential water source. Since then, similar observations of plant water isotopic signatures that do not match any available water source have been reported from a range of ecosystems worldwide. Here, we use a combination of non‐destructive in situ isotopic soil water sampling along with destructive soil sampling and cryogenic water extraction to demonstrate that isotopically distinct water pools can be identified in soils at the same site as the 1991 study during parts of the summer growing season. Water extracted from xylem tissues shows that streamside boxelder and bigtooth maple at the sites were predominantly using soil water with an isotopic composition similar to that measured by the in situ soil measurement technique. We introduce the use of water vapour probes that were directly attached to intact tree roots in situ to measure the isotopic composition of root xylem water and how it varies through the growing season and evaluate their potential and utility.  相似文献   
5.
Array-CGH     
We report on our experience with array CGH analysis on 1310 samples over the last 5?years. The number of copy number variants (CNV) rises as the resolution of the arrays increases; however, the relevance of some of these findings is difficult to evaluate. Deletion or duplication in 16p11.2 was the most frequently diagnosed pathogenic CNV. Clinically relevant findings which were not directly connected to the query were observed in about 0.2% of patients.  相似文献   
6.
It has been reported that the adjuvant-induced inflammation could affect drug metabolism in liver. Here we further investigated the effect of inflammation on drug transport in liver using taurocholate as a model drug. The hepatic disposition kinetics of [(3)H]taurocholate in perfused normal and adjuvant-treated rat livers were investigated by the multiple indicator dilution technique and data were analyzed by a previously reported hepatobiliary taurocholate transport model. Real-time RT-PCR was also performed to determine the mRNA expression of liver bile salt transporters in normal and diseased livers. The uptake and biliary excretion of taurocholate were impaired in the adjuvant-treated rats as shown by decreased influx rate constant k(in) (0.65 ± 0.09 vs. 2.12 ± 0.30) and elimination rate constant k(be) (0.09 ± 0.02 vs. 0.17 ± 0.04) compared with control rat group, whereas the efflux rate constant k(out) was greatly increased (0.07 ± 0.02 vs. 0.02 ± 0.01). The changes of mRNA expression of liver bile salt transporters were found in adjuvant-treated rats. Hepatic taurocholate extraction ratio in adjuvant-treated rats (0.86 ± 0.05, n = 6) was significantly reduced compared with 0.93 ± 0.05 (n = 6) in normal rats. Hepatic extraction was well correlated with altered hepatic ATP content (r(2) = 0.90). In conclusion, systemic inflammation greatly affects hepatic ATP content/production and associated transporter activities and causes an impairment of transporter-mediated solute trafficking and pharmacokinetics.  相似文献   
7.
High-throughput screening, based on subcellular imaging, has become a powerful tool in lead discovery. Through the generation of high-quality images, not only the specific target signal can be analyzed but also phenotypic changes of the whole cell are recorded. Yet analysis strategies for the exploration of high-content screening results, in a manner that is independent from predefined control phenotypes, are largely missing. The approach presented here is based on a well-established modeling technique, self-organizing maps (SOMs), which uses multiparametric results to group treatments that create similar morphological effects. This report describes a novel visualization of the SOM clustering by using an image of the cells from each node, with the most representative cell highlighted to deploy the phenotype described by each node. The approach has the potential to identify both expected hits and novel cellular phenotypes. Moreover, different chemotypes, which cause the same phenotypic effects, are identified, thus facilitating "scaffold hopping."  相似文献   
8.
In many retinal proteins the proton transfer from the Schiff base to the counterion represents a functionally important step of the photoreaction. In the signaling state of sensory rhodopsin II from Natronobacterium pharaonis this transfer has already occurred, but in the counterion mutant Asp75Asn it is blocked during all steps of the photocycle. Therefore, the study of the molecular changes during the photoreaction of this mutant should provide a deeper understanding of the activation mechanism, and for this, we have applied time-resolved step-scan FTIR spectroscopy. The photoreaction is drastically altered; only red-shifted intermediates are formed with a chromophore strongly twisted around the 14-15 single bond. In addition, the photocycle is shortened by 2 orders of magnitude. Nevertheless, a transition involving only protein changes similar to that of the wild type is observed, which has been correlated with the formation of the signaling state. However, whereas in the wild type this transition occurs in the millisecond range, it is shortened to 200 micros in the mutant. The results are discussed with respect to the altered electrostatic interactions, role of proton transfer, the published 3D structure, and physiological activity.  相似文献   
9.
Summary Peptidase A polymorphism was investigated in 83 mother-child pairs and in a population sample of 182 unrelated individuals from southwestern Germany. Hereby the formal hypothesis that there are two common alleles, PepA1 and PepA8, at an autosomal locus PepA, was confirmed. The frequency of the PepA8 allele was calculated to be 0.27±0.02.  相似文献   
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