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31.
The objective of this study was to look for early pathological changes in stress target organs, adrenal glands, and stomachs in captured wild African green monkeys (AGMs). Three wild-caught male AGMs and seven singly housed wild AGMs were euthanized on day 1 and day 45 post-capture, respectively, and compared with four wild males euthanized with a rifle as controls. Morphometric analyses of the adrenal cortices and the cortical zones were done using an image analyzer. By day 45, the confined animals were clinically healthy, but had lost 47% mean body weight despite ad libitum feeding. The width of zona fasciculata in the controls was significantly smaller compared with that of 45-day monkeys (P < 0.05). Numerous acidophilic, hyperplastic and hypertrophic cells were present in the zona fasciculata of the 1-day confined AGMs. In the 45-day monkeys, there was glandular hyperplasia in the zona glomerulosa and the acini were distended and vacuous; yellow, granular pigmentation was distributed in the zona fasciculata. Acute stomach lesions represented by petechiation were seen in one monkey on day 1. Deep, circular, mucosal erosions, one to five in number and measuring from 0.5 to 1 mm in diameter, were present in three monkeys on day 45 post-capture. There were no adrenal cortex or stomach lesions in the rifle-shot monkeys. In conclusion, pathological lesions in the adrenal glands, and stomachs of the wild AGMs and weight loss occurred within the initial 45-day period following capture and confinement. 相似文献
32.
McPherson JP Tamblyn L Elia A Migon E Shehabeldin A Matysiak-Zablocki E Lemmers B Salmena L Hakem A Fish J Kassam F Squire J Bruneau BG Hande MP Hakem R 《The EMBO journal》2004,23(18):3677-3688
The Drosophila melanogaster warts/lats tumour suppressor has two mammalian counterparts LATS1/Warts-1 and LATS2/Kpm. Here, we show that mammalian Lats orthologues exhibit distinct expression profiles according to germ cell layer origin. Lats2(-/-) embryos show overgrowth in restricted tissues of mesodermal lineage; however, lethality ultimately ensues on or before embryonic day 12.5 preceded by defective proliferation. Lats2(-/-) mouse embryonic fibroblasts (MEFs) acquire growth advantages and display a profound defect in contact inhibition of growth, yet exhibit defective cytokinesis. Lats2(-/-) embryos and MEFs display centrosome amplification and genomic instability. Lats2 localizes to centrosomes and overexpression of Lats2 suppresses centrosome overduplication induced in wild-type MEFs and reverses centrosome amplification inherent in Lats2(-/-) MEFs. These findings indicate an essential role of Lats2 in the integrity of processes that govern centrosome duplication, maintenance of mitotic fidelity and genomic stability. 相似文献
33.
34.
Direct comparison of antigen production and induction of apoptosis by canarypox virus- and modified vaccinia virus ankara-human immunodeficiency virus vaccine vectors 下载免费PDF全文
Zhang X Cassis-Ghavami F Eller M Currier J Slike BM Chen X Tartaglia J Marovich M Spearman P 《Journal of virology》2007,81(13):7022-7033
Recombinant poxvirus vectors are undergoing intensive evaluation as vaccine candidates for a variety of infectious pathogens. Avipoxviruses, such as canarypox virus, are replication deficient in mammalian cells by virtue of a poorly understood species-specific restriction. Highly attenuated vaccinia virus strains such as modified vaccinia virus Ankara (MVA) are similarly unable to complete replication in most mammalian cells but have an abortive-late phenotype, in that the block to replication occurs post-virus-specific DNA replication. In this study, an identical expression cassette for human immunodeficiency virus gag, pro, and env coding sequences was placed in canarypox virus and MVA vector backbones in order to directly compare vector-borne expression and to analyze differences in vector-host cell interactions. Antigen production by recombinant MVA was shown to be greater than that from recombinant canarypox virus in the mammalian cell lines and in the primary human cells tested. This observation was primarily due to a longer duration of antigen production in recombinant MVA-infected cells. Apoptosis induction was found to be more profound with the empty canarypox virus vector than with MVA. Remarkably, however, the inclusion of a gag/pro/env expression cassette altered the kinetics of apoptosis induction in recombinant MVA-infected cells to levels equal to those found in canarypox virus-infected cells. Antigen production by MVA was noted to be greater in human dendritic cells and resulted in enhanced T-cell stimulation in an in vitro antigen presentation assay. These results reveal differences in poxvirus vector-host cell interactions that should be relevant to their use as immunization vehicles. 相似文献
35.
Farah T. van Genderen Frans K. Gorus Ilse Vermeulen Evilien M.F. Vekens Pieter E.M. De Pauw Daniel G. Pipeleers Chris Van Schravendijk 《Analytical biochemistry》2010,404(1):8-13
We present a time-resolved fluorescence immunoassay (TR-FIA) for the measurement of rat insulin in cell extracts and culture media. This assay is based on the binding of two monoclonal antibodies to different parts of the insulin molecule in a 96-well microtiter plate. For the detection, europium-labeled streptavidin that interacts with the second biotinylated antibody is used. Samples of 25 μl could be analyzed in less than 2 days with a measuring range between 5 and 1250 pg (0.2-50 μg/L or 34.4-8600 pM). The inter- and intraassay percentage coefficients of variation were less than 8.3 and 5.1, respectively. Recoveries of 0.48 to 40 μg/L rat insulin, added to culture medium, ranged between 94 and 107%. Results were significantly correlated with those of an in-house radioimmunoassay (RIA) for rodent insulin (P < 0.0001, r2 = 0.99). The TR-FIA method had a similar detection limit (0.16 μg/L), but its working range was at least 5-fold larger. Additional advantages include the lower cost, the applicability to measurements in tissue and serum, and the quantification of insulin from other species. 相似文献
36.
Lu Shi Jing Farah Fathiah Muzaffar Shah Mohd Saberi Mohamad Nur Laily Hamran Abdul Hakim Mohamed Salleh Safaai Deris Hany Alashwal 《Biotechnology and Bioprocess Engineering》2014,19(4):568-585
Metabolic network analysis has attracted much attention in the area of systems biology. It has a profound role in understanding the key features of organism metabolic networks and has been successfully applied in several fields of systems biology, including in silico gene knockouts, production yield improvement using engineered microbial strains, drug target identification, and phenotype prediction. A variety of metabolic network databases and tools have been developed in order to assist research in these fields. Databases that comprise biochemical data are normally integrated with the use of metabolic network analysis tools in order to give a more comprehensive result. This paper reviews and compares eight databases as well as twenty one recent tools. The aim of this review is to study the different types of tools in terms of the features and usability, as well as the databases in terms of the scope and data provided. These tools can be categorised into three main types: standalone tools; toolbox-based tools; and web-based tools. Furthermore, comparisons of the databases as well as the tools are also provided to help software developers and users gain a clearer insight and a better understanding of metabolic network analysis. Additionally, this review also helps to provide useful information that can be used as guidance in choosing tools and databases for a particular research interest. 相似文献
37.
Oliveira DM Nakaie CR Sousa AD Farah CS Reinach FC 《The Journal of biological chemistry》2000,275(36):27513-27519
The in vitro Ca(2+) regulation of the actomyosin Mg(2+)-ATPase at physiological ratios of actin, tropomyosin, and troponin occurs only in the presence of troponin T. We have previously demonstrated that a polypeptide corresponding to the first 191 amino acids of troponin T (TnT-(1-191)) activates the actomyosin Mg(2+)-ATPase in the presence of tropomyosin. In order to further characterize this activation domain, we constructed troponin T fragments corresponding to residues 1-157 (TnT-(1-157)), 1-76 (TnT-(1-76)), 77-157 (TnT-(77-157)), 77-191 (TnT-(77-191)), and 158-191 (TnT-(158-191)). Assays using these fragments demonstrated the following: (a) residues 1-76 do not bind to tropomyosin or actin; (b) residues 158-191 bind to actin cooperatively but not to tropomyosin; (c) the sequence 77-157 is necessary for troponin interaction with residue 263 of tropomyosin; (d) TnT-(77-191) on its own activates the actomyosin ATPase activity as described previously for TnT-(1-191). TnT-(1-157), TnT-(1-76), TnT-(77-157), TnT-(158-191), and combinations of TnT-(158-191) with TnT-(1-157) or TnT-(77-157) showed no effect on the ATPase activity. We conclude that the activation of actomyosin ATPase activity is mediated by a direct interaction between amino acids 77 and 191 of troponin T, tropomyosin, and actin. 相似文献
38.
Harold L. Asch Robert Z. Vinci Jae Y. Chang Farah Natoli Daniel L. Stoler Garth R. Anderson Bonnie B. Asch 《Cell biology international》1993,17(10):961-968
Amplified expression of the endogenous retrotransposons, intracisternal A particles (IAPs) and murine leukemia virus-related elements (MLVEs), along with decreased expression of VL30 elements frequently occurs during mouse mammary tumorigenesis. We have now analyzed the expression of these retroelements during the normal developmental and differentiation cycle of the mammary gland as found in virgin, pregnant, lactating, and post-lactation adult female BALB/c mice. Retrotransposon expression was either unchanged or decreased during the progressive stages of the cycle compared to virgin tissue. Likewise, growth of mammary epithelial cells in primary culture had little or no effect on expression of IAPs, MLVEs and VL30 sequences. Thus, the dramatic changes involving these retrotransposons in many mouse mammary tumors appear unrelated to any normal state. 相似文献
39.
D.L. Langoi P.G. Mwethera K.S.P. Abelson I.O. Farah & H.E. Carlsson 《Journal of medical primatology》2009,38(6):404-410
Background The potential of Atipamezole (ATI) to reverse Ketamine/Xylazine (KET/XYL) anesthesia in the Olive baboon ( Papio anubis ) was studied.
Methods Anesthesia was induced with 10 mg/kg KET and 0.5 mg/kg XYL intramuscularly. Mean arousal time (MAT), heart rate (HR), systolic arterial blood pressure (SAP), rectal temperature, respiratory rate (RR), and hemoglobin oxygen saturation (SpO2 ) were monitored. Baboons were treated with: KET/XYL only, KET/XYL followed by 100 μg/kg ATI or by 200 μg/kg ATI administered 25 minutes after KET/XYL.
Results Atipamezole rapidly reversed depressed HR and SAP (10 ± 5.2 minutes), RR (5 ± 2 minutes) and SpO2 (3 ± 6 minutes) and significantly decreased MAT (13 ± 2.2 minutes) vs. KET/XYL alone (35 ± 5 minutes). Emesis was absent and salivation was observed after administration of 200 μg/kg ATI only.
Conclusions Atipamezole at 100 μg/kg is sufficient for rapid and smooth reversal of KET/XYL anesthesia in the Olive baboon with minimal side effects. 相似文献
Methods Anesthesia was induced with 10 mg/kg KET and 0.5 mg/kg XYL intramuscularly. Mean arousal time (MAT), heart rate (HR), systolic arterial blood pressure (SAP), rectal temperature, respiratory rate (RR), and hemoglobin oxygen saturation (SpO
Results Atipamezole rapidly reversed depressed HR and SAP (10 ± 5.2 minutes), RR (5 ± 2 minutes) and SpO
Conclusions Atipamezole at 100 μg/kg is sufficient for rapid and smooth reversal of KET/XYL anesthesia in the Olive baboon with minimal side effects. 相似文献
40.
Shubha Priyamvada Sara A. Khan Md.Wasim Khan Sheeba Khan Neelam Farooq Farah Khan A.N.K. Yusufi 《Prostaglandins, leukotrienes, and essential fatty acids》2010,82(1):35-44
Human and animal exposure demonstrates that uranium is nephrotoxic. However, attempts to reduce it were not found suitable for clinical use. Dietary fish oil (FO) enriched in ω-3 fatty acids reduces the severity of cardiovascular and renal diseases. Present study investigates the protective effect of FO on uranyl nitrate (UN)-induced renal damage. Rats prefed with experimental diets for 15 days, given single nephrotoxic dose of UN (0.5 mg/kg body weight) intraperitoneally. After 5 d of UN treatment, serum/urine parameters, enzymes of carbohydrate metabolism, brush border membrane (BBM), oxidative stress and phosphate transport were analyzed in rat kidney. UN nephrotoxicity was characterized by increased serum creatinine and blood urea nitrogen. UN increased the activity of lactate dehydrogenase and NADP-malic enzyme whereas decreased malate, isocitrate and glucose-6-phophate dehydrogenases; glucose-6-phophatase, fructose-1, 6-bisphosphatase and BBM enzyme activities. UN caused oxidant/antioxidant imbalances as reflected by increased lipid peroxidation, activities of superoxide dismutase, glutathione peroxidase and decreased catalase activity. Feeding FO alone increased activities of enzymes of glucose metabolism, BBM, oxidative stress and Pi transport. UN-elicited alterations were prevented by FO feeding. However, corn oil had no such effects and was not similarly effective. In conclusion, FO appears to protect against UN-induced nephrotoxicity by improving energy metabolism and antioxidant defense mechanism. 相似文献