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981.
M K Ruohonen-Lehto M F Rothschild R G Larson M K Ruohonen-Lehto M F Rothschild R G Larson 《Animal genetics》1993,24(1):67-68
Pigs from a population consisting of eight US breeds or strains and three Chinese breeds were examined by restriction fragment length polymorphism (RFLP) analysis of the heat shock protein HSP70 gene(s). Limited polymorphisms with PstI and PvuII restriction enzymes were observed, but there were no polymorphisms with BomIII and BglI. 相似文献
982.
《Expert review of proteomics》2013,10(6):685-695
Dried blood spots (DBS) have been used as a clinical sample format for over 50 years, and have been analyzed for small molecules and metabolites by mass spectrometry (MS) since the early 1990s. In the meantime, MS has become the tool of choice in proteomics. Despite this obvious avenue of scientific investigation, the marriage of MS and DBS protein analysis has been comparatively recent. DBS are a potentially rich source of protein biomarkers that remain to be exploited. This article focuses on the progress made in the mass spectrometric analysis of proteins from DBS and discusses the benefits and challenges facing this emerging field. 相似文献
983.
Summary By means of a preembedding immuno-electronmicroscopic technique, a large number of nerve endings containing a substance related to human growth hormonereleasing factor (hGRF) have been demonstrated in the paraventricular nucleus of the guinea pig. They made synaptic contacts primarily with dendritic shafts: 80% of these contacts were symmetrical. The immunoprecipitate was located mainly in large granules and around small clear vesicles. These findings suggest that a peptide related to hGRF may play a role in neural communication in the paraventricular nucleus. 相似文献
984.
V. K. Dwivedi M. Chandra P. C. Misra Aparna Misra M. K. Misra 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):43-46
Pro-oxidant and anti-oxidant systems and their levels have significant roles in occlusive vascular diseases. In the present communication, we have measured the levels of some representative anti-oxidant enzymes in the blood of the patients of myocardial infarction after reperfusion and compared them to age and sex matched healthy persons. Our findings show that the activities of anti-oxidant enzymes (viz. SOD, catalase and glutathione reductase) are significantly decreased whereas there is significant increase in the levels of malonaldialdehyde (a marker of free radical-mediated damage) in the patients. The findings point out that ischemic myocardial disorders are associated with excessive free radical generation and free radical-mediated damage of lipids. 相似文献
985.
Elena S. Odintsova Pavel S. Dmitrenok Valentina N. Buneva Georgy A. Nevinsky 《Journal of molecular recognition : JMR》2013,26(3):121-135
HIV‐infected patients possess anti‐integrase (IN) IgGs and IgMs that, after isolation by chromatography on IN‐Sepharose, unlike canonical proteases, specifically hydrolyze only IN but not many other tested proteins. Hydrolysis of intact globular IN first leads to formation of many long fragments of protein, while its long incubation with anti‐IN antibodies, especially in the case of abzymes (Abzs) with a high proteolytic activity, results in the formation of short and very short oligopeptides (OPs). To identify all sites of IgG‐mediated proteolysis corresponding to known AGDs of integrase, we have used a combination of reverse‐phase chromatography, matrix‐assisted laser desorption/ionization spectrometry, and thin‐layer chromatography to analyze the cleavage products of two 20‐mer OPs corresponding to these AGDs. Both OPs contained 9–10 mainly clustered major, medium, and minor sites of cleavage. The main superficial cleavage sites of the AGDs in the intact IN and sites of partial or deep hydrolysis of the peptides analyzed do not coincide. The active sites of anti‐IN Abzs are localized on their light chains, whereas the heavy chains are responsible for the affinity of protein substrates. Interactions of intact globular proteins with both light and heavy chains of Abzs provide high specificity of IN hydrolysis. The affinity of anti‐IN Abzs for intact integrase was ~1000‐fold higher than for the OPs. The data suggest that both OPs interact mainly with the light chains of different monoclonal Abzs of the total pool of IgGs, which possesses lower affinity for substrates; and therefore, depending on the oligopeptide sequences, their hydrolysis may be less specific and remarkably different in comparison with the cleavage of intact globular IN. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
986.
J. Tomkova D. Friedecky P. Vyskocilova T. Adam 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):656-660
Inosine triphosphate pyrophosphohydrolase (ITPase) catalyzing the pyrophosphohydrolysis of inosine triphosphate, deoxyinosine triphosphate and xanthosine triphosphate is involved in the metabolism and tolerance of thiopurine drugs. ITPase activity plays an important role in the prediction of toxicity to thiopurine therapy. Activities in dry blood spots were compared with fresh erythrocytes. Samples were incubated with inosine triphosphate, then inosine monophosphate was determined by a capillary electrophoresis method. Calculated enzyme activities obtained from dry blood spots were in good accordance with activity in fresh erythrocytes. 相似文献
987.
《Free radical research》2013,47(1):759-760
In this study, we tried to evaluate the usefulness of Superoxide Dismutase (SOD) activity in detecting gastric cancer. SOD was determined according to M. Minami and H. Yoshikawa. a simple and inexpensive assay method. For II fibrognstroscopy and pathological proved gastric cancer cases, the average levels of SOD activity was found significantly lower than 30 patients with gastric diseases, 8 patients with atypical hyperplasia and 32 controls. 相似文献
988.
Karina D. Asensi Rodrigo S. Fortunato Danúbia S. dos Santos Thaísa S. Pacheco Danielle F. de Rezende Deivid C. Rodrigues Fernanda C. P. Mesquita Tais H. Kasai‐Brunswick Antonio C. Campos de Carvalho Denise P. Carvalho Adriana B. Carvalho Regina C. dos S. Goldenberg 《Journal of cellular and molecular medicine》2014,18(5):824-831
Properties of induced pluripotent stem cells (iPSC) have been extensively studied since their first derivation in 2006. However, the modification in reactive oxygen species (ROS) production and detoxification caused by reprogramming still needs to be further elucidated. The objective of this study was to compare the response of iPSC generated from menstrual blood–derived mesenchymal stem cells (mb‐iPSC), embryonic stem cells (H9) and adult menstrual blood–derived mesenchymal stem cells (mbMSC) to ROS exposure and investigate the effects of reprogramming on cellular oxidative stress (OS). mbMSC were extremely resistant to ROS exposure, however, mb‐iPSC were 10‐fold less resistant to H2O2, which was very similar to embryonic stem cell sensitivity. Extracellular production of ROS was also similar in mb‐iPSC and H9 and almost threefold lower than in mbMSC. Furthermore, intracellular amounts of ROS were higher in mb‐iPSC and H9 when compared with mbMSC. As the ability to metabolize ROS is related to antioxidant enzymes, we analysed enzyme activities in these cell types. Catalase and superoxide dismutase activities were reduced in mb‐iPSC and H9 when compared with mbMSC. Finally, cell adhesion under OS conditions was impaired in mb‐iPSC when compared with mbMSC, albeit similar to H9. Thus, reprogramming leads to profound modifications in extracellular ROS production accompanied by loss of the ability to handle OS. 相似文献
989.
《Animal : an international journal of animal bioscience》2014,8(5):836-843
Surgical castration in pig husbandry is criticized for welfare reasons. Thus, it is necessary to evaluate alternative ways of rearing male pigs, such as entire or immunocastrated animals. Immunocastration is a vaccination directed against gonadotropin-releasing hormone (GnRH) to suppress the production of sexual hormones. This study aimed at investigating the effects of these two methods of castration in comparison with intact male pigs on blood T-lymphocyte subsets and function, the immunoglobulin (Ig) response to an influenza vaccine and health markers during sexual development. A total of 70 animals were allocated to three experimental groups: entire (E), surgically castrated at 5 to 6 days of age (SC), and immunized against GnRH at 3 and 4 months of age (IC). Blood samples were collected at 3, 4 and 5 months. At slaughter, global health status and body and spleen weights were measured. Results showed that SC male pigs had fewer blood lymphocytes than E pigs at 4 and 5 months (P<0.05), whereas IC pigs did not differ significantly from E pigs. The percentages of CD3+, CD3+CD4+ and CD3+CD8+ lymphocytes were not altered by treatment (P>0.1). Compared with E pigs, the SC pigs had a higher percentage of CD3+CD4+CD8+ cells at 4 months, whereas the IC pigs had a higher percentage at 5 months (P<0.05). Regarding γδT cells, SC pigs had a lower percentage than E pigs at 4 and 5 months (P<0.05), whereas IC pigs did not differ significantly from E pigs at any age. However, there were no consequences on T-lymphocyte proliferation and total IgG or anti-influenza Ig. At slaughter, relative spleen weight was decreased in IC pigs, whereas pneumonia score was decreased in SC pigs relatively to E pigs. Overall, no clear functional consequences of either method on commercial pig immune abilities were demonstrated, but more investigations are required to ascertain this conclusion. 相似文献
990.
Rambouillet sheep originating from Spanish Merino have been maintained in France as a small and closed flock since their importation. After 190 years of independent evolution, the flock has markedly differentiated from its Spanish parental population. The observed differences between them were characterized by the fixation in Rambouillet of the Mb and F30 alleles, which occurred in Spanish Merino with frequencies of 0.90 and 0.80 respectively (at two distinct blood group loci M and F30) and by the absence in Rambouillet of other alleles or phenogroups (at the Tf and the A, B, C blood group loci) which were observed in Spanish Merino with frequencies ranging from 0.10 to 0.28. On the basis of their phenotypic distributions at 11 blood polymorphic loci, the two populations differed significantly from each other (total chi 2 values = 352.62, 23 df, P less than 0.001). By comparing the observed magnitude of gene frequency differences between Rambouillet and Spanish Merino with the estimate of inbreeding coefficient for Rambouillet obtained from pedigrees, it appeared that the observed genetic differences could be attributed to the evolutionary change due to random drift in the small and closed flock of Rambouillet. 相似文献