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951.
Vasikaran S 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2008,29(Z1):S99-S103
* Clinical laboratories should be able to offer interpretation of the results they produce. * At a minimum, contact details for interpretative advice should be available on laboratory reports.Interpretative comments may be verbal or written and printed. * Printed comments on reports should be offered judiciously, only where they would add value; no comment preferred to inappropriate or dangerous comment. * Interpretation should be based on locally agreed or nationally recognised clinical guidelines where available. * Standard tied comments ("canned" comments) can have some limited use.Individualised narrative comments may be particularly useful in the case of tests that are new, complex or unfamiliar to the requesting clinicians and where clinical details are available. * Interpretative commenting should only be provided by appropriately trained and credentialed personnel. * Audit of comments and continued professional development of personnel providing them are important for quality assurance. 相似文献
952.
Carboxylic acid transporters form a heterogeneous group of proteins, presenting diverse mechanisms of action and regulation, and belonging to several different families. Multiple physiological and genetic studies in several organisms, from yeast to mammals, have allowed the identification of various genes coding for carboxylate transporters. Detailed understanding of the metabolism and transport of these nutrients has become more important than ever, both from a fundamental and from an applied point of view. Under a biotechnological perspective, the increasing economic value of these compounds has boosted this field of research considerably. Here we review the current knowledge on yeast carboxylate transporters, at the biochemical and molecular level, focusing also on recent biotechnological developments. 相似文献
953.
CYP2E1 substrate inhibition. Mechanistic interpretation through an effector site for monocyclic compounds 总被引:1,自引:0,他引:1
Collom SL Laddusaw RM Burch AM Kuzmic P Perry MD Miller GP 《The Journal of biological chemistry》2008,283(6):3487-3496
In this study we offer a mechanistic interpretation of the previously known but unexplained substrate inhibition observed for CYP2E1. At low substrate concentrations, p-nitrophenol (pNP) was rapidly turned over (47 min(-1)) with relatively low K(m) (24 microM); nevertheless, at concentrations of >100 microM, the rate of pNP oxidation gradually decreased as a second molecule bound to CYP2E1 through an effector site (K(ss) = 260 microm), which inhibited activity at the catalytic site. 4-Methylpyrazole (4MP) was a potent inhibitor for both sites through a mixed inhibition mechanism. The K(i) for the catalytic site was 2.0 microM. Although we were unable to discriminate whether an EIS or ESI complex formed, the respective inhibition constants were far lower than K(ss). Bicyclic indazole (IND) inhibited catalysis through a single CYP2E1 site (K(i) = 0.12 microM). Similarly, 4MP and IND yielded type II binding spectra that reflected the association of either two 4MP or one IND molecule(s) to CYP2E1, respectively. Based on computational docking studies with a homology model for CYP2E1, the two sites for monocyclic molecules, pNP and 4MP, exist within a narrow channel connecting the active site to the surface of the enzyme. Because of the presence of the heme iron, one site supports catalysis, whereas the other more distal effector site binds molecules that can influence the binding orientation and egress of molecules for the catalytic site. Although IND did not bind these sites simultaneously, the presence of IND at the catalytic site blocked binding at the effector site. 相似文献
954.
Jesudason EP Masilamoni JG Ashok BS Baben B Arul V Jesudoss KS Jebaraj WC Dhandayuthapani S Vignesh S Jayakumar R 《Molecular and cellular biochemistry》2008,311(1-2):145-156
Aβ amyloid peptide is believed to induce oxidative stress leading to inflammation, which is postulated to play a significant
role in the toxicity of Alzheimer’s disease (AD). This study was designed to investigate the inhibitory effects of dl-α lipoic acid (LA), a potential free radical scavenger, on oxidative vulnerability induced by intraperitoneal injection of
Aβ25–35 amyloid fibrils in mice. Mice were divided into three groups: control, Aβ amyloid toxicity induced (AT), and LA treated (ATL).
Blood Plasma was separated, liver, spleen and brain were dissected and analysis of oxidants, antioxidants, ATPases, glial
fibrillary acidic protein (GFAP) and nuclear factor kappa-B (NFκB) were carried out. Results show biochemical parameters such
as reactive oxygen species (ROS) and lipid peroxidation (LPO) were significantly lowered (P < 0.05) and levels of antioxidants and ATPase (P < 0.05) were significantly increased (P < 0.05) in hepatocytes, splenocytes and astrocytes of the ATL group. Moreover, our histological results revealed a decreased
GFAP immunoreactivity in the neocortical region and NFκB immunoreactivity in neocortex, liver and spleen. This study reiterates
LA as a potent free radical scavenger to combat oxidative vulnerability in the treatment for Aβ amyloid toxicity. 相似文献
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958.
In this paper, we provide a stochastic ordering of the Studentized range statistics under a balanced one-way ANOVA model. Based on this result we show that, when restricted to the multiple comparisons with the best, the Newman-Keuls (NK) procedure strongly controls experimentwise error rate for a sequence of null hypotheses regarding the number of largest treatment means. In other words, the NK procedure provides an upper confidence bound for the number of best treatments. 相似文献
959.
Xie LH Sin FW Cheng SC Cheung YK Chan KT Xie Y Xie Y 《Cancer immunology, immunotherapy : CII》2008,57(7):1029-1038
Induction of anti-tumor immune responses by dendritic cells (DCs) transduced with a recombinant adeno-associated virus type
2 (rAAV2) encoding tumor antigens is considered a promising approach for cancer vaccine development. CML28, a novel antigen
with the properties of cancer/testis (CT) antigens, is an attractive target for antigen-specific immunotherapy. Here we investigated
the feasibility of inducing CML28-specific cytotoxic T lymphocyte (CTL) responses using DCs transduced with the rAAV2 vectors
containing the CML28 gene (rAAV/CML28). Using an adenovirus-free packaging system, rAAV/CML28 was generated. The transduction
efficiency of rAAV/CML28 in DCs increased in a multiplicity of infection (MOI)-dependent manner. The rAAV/CML28 transduction
did not impair DC maturation, but even enhanced the CD80 expression. The rAAV/CML28-transduced DCs induced CML28-specific
CTLs which exhibited a MHC class I-mediated antigen-specific lytic activity against CML28-bearing tumor cell lines (HepG2
and MCF-7) as well as the primary leukemia blasts. These findings suggest that rAAV/CML28-transduced DCs vaccine may serve
as a feasible approach for the treatment of CML28-associated cancers. 相似文献
960.
Mathara JM Schillinger U Kutima PM Mbugua SK Guigas C Franz C Holzapfel WH 《Current microbiology》2008,56(4):315-321
Lactobacillus plantarum was the major species among the lactic acid bacterial strains isolated from traditional fermented milk of the Maasai in Kenya.
Selected strains were characterized for their functional properties using in vitro standard procedures. All strains expressed
acid tolerance at pH 2.0 after 2-h exposure of values that ranged from 1% to 100%, while bile tolerance of acid-stressed cells
at 0.3% oxgal varied from 30% to 80%. In vitro adhesion to the mucus-secreting cell line HT 29 MTX and binding capacity to
extracellular protein matrices was demonstrated for several strains. The four strains tested in a simulated stomach duodenum
passage survived with recovery rates ranging from 17% to 100%. Strains were intrinsically resistant to several antibiotics
tested. From these in vitro studies, a number of Lb. plantarum strains isolated from the Maasai traditional fermented milk showed probiotic potential. The strains are good candidates for
multifunctional starter culture development. 相似文献