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1.
Summary Glucose-6-phosphate dehydrogenase (G6PD) enzyme from cases known to be completely or mildly deficient were analyzed. The enzymes were purified from blood samples by utilizing DEAE-52 cellulose pH 7.0 column chromatography and ammonium sulphate precipitation. Biochemical and electrophoretic properties of G6PD were studied in these partially purified enzymes. In this study wer report three new variants from Çukurova, named Adana, Samanda, and Balcali. Variant I (G6PD Adana) had a high Km for G6P (210 M) and NADP (13M). Utilization of 2d-G6P was 38%. It had a slow electrophoretic mobility, a biphasic pH optimum curve, and abnormal heat stability. Variant II (G6PD Samanda) had a low Km for G6P (25M) and a high Km for NADP (18M). The rate of utilization of 2d-G6P was normal. G6PD Samanda deviated from the normal enzyme by its biphasic pH optimum curve and its slow electrophoretic mobility. Variant III (G6PD-Balcali) had a normal Km G6P, NADP and rate of utilization of 2d-G6P. However, it showed a biphasic pH optimum curve and slow electrophoretic mobility.  相似文献   

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《Microbiology》2011,80(6):893-893

In Memorium

Georgii Aleksandrovich Zavarzin, January 28, 1933–September 6, 2011  相似文献   

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Natural bond orbital (NBO), nuclear magnetic resonance (NMR) analysis and hybrid-density functional theory based method (B3LYP/Def2-TZVPP) were used to investigate the correlation between the nucleus-independent chemical shifts [NICS, as an aromaticity criterion], σ Al(1)-X2(b)σ*Al(3)-X4(b) electron delocalizations and the dissociation energies of Al2F6, Al2Cl6, Al2Br6 and Al2I6 to 2AlX3 (X?=?F, Cl, Br, I). The results obtained showed that the dissociation energies of Al2F6, Al2Cl6, Al2Br6 and Al2I6 decrease from Al2F6 to Al2I6. Like aromatic molecules, these compounds have relatively significant negative NICSiso(0) values. Clearly, based on magnetic criteria, they exhibit aromatic character and make it possible to consider them as σ-delocalized aromatic species, such as Möbius σ-aromatic species. The σ-aromatic character which is demonstrated by their NICSiso(0) values decreases from Al2F6 to Al2I6. The NICSiso values are dominated by the in-plane σ22 (i.e., σyy, the plane containing halogen atoms bridged) chemical shift components. The increase of the NICSiso values explains significantly the decrease of the corresponding dissociation energies of Al2F6, Al2Cl6, Al2Br6 and Al2I6. Importantly, the NBO results suggest that in these compounds the dissociation energies are controlled by the stabilization energies associated with σ Al(1)-X2(b)σ*Al(3)-X4(b) electron delocalizations. The decrease of the stabilization energies associated with σ Al(1)-X2(b)σ*Al(3)-X4(b) electron delocalizations is in accordance with the variation of the calculated NICSiso values. The correlations between the dissociation energies of Al2F6, Al2Cl6, Al2Br6 and Al2I6, σ Al(1)-X2(b)σ*Al(3)-X4(b) electron delocalizations, natural atomic orbitals (NAOs) and NICSiso values have been investigated.  相似文献   

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Selective acid-catalysed methanolysis of 2,3,2′,3′-tetra-O-benzyl-4,6:4′,6′-di-O-benzylidene-α,α-trehalose yielded the monobenzylidene derivative, which was converted into the 4,6-dimesylate. Selective nucleophilic displacement of the primary sulphonyloxy group then gave 2,3-di-O-benzyl-6-deoxy-6-fluoro-4-O-mesyl-α-d-glucopyranosyl 2,3-di-O-benzyl-4,6-O-benzylidene-α-d-glucopyranoside. Removal of the protecting groups then yielded 6-deoxy-6-fluoro-α,α-trehalose. In addition, 6-deoxy-6-fluoro-4-O-mesyl-α,α-trehalose and a derivative of 4-chloro-4,6-dideoxy-6-fluoro-α-d-galactopyranosyl α-d-glucopyranoside were also prepared from the same substrate. Iodide displacement of 2,3-di-O-benzyl-4,6-di-O-mesyl-α-d-glucopyranosyl 2,3-di-O-benzyl-4,6-di-O-mesyl-α-d-glucopyranoside afforded the 6-iodide and 6,6′-di-iodide in yields of 31 and 36%, respectively. Similarly, the 6-azide and 6,6′-diazide were isolated in yields of 17 and 21%, respectively.  相似文献   

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Datura meteloides; plants were fed with tiglic acid-[-14C] via the roots and after 2 days the percentage incorporation into the alkaloids 3α-tigloyloxytropane, 3α,6β-ditigloyloxytropane, meteloidine and 3α,6β-ditigloyloxytropan-7β-ol were 15·2, 1·82, 2·2 and 1·8 respectively. 3α,6β-Ditigloyloxytropane was partially hydrolysed to 6β-hydroxy-3α-tigloyloxytropane which contained 58·1% of the radioactivity of the original base, whereas 3α,6β-ditigloyloxytropan-7β-ol gave meteloidine containing only 9·2% of the original activity. The results suggest that the di- and tri-hydroxytropanes may be formed by different routes.  相似文献   

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Abstract

Bromination of the title compound 1 with bromine in phosphate buffer has led to 8-bromo-N6, N6-dimethyl-2′,3′-0-isopropylidene-adenosine (2) and 2′,3′-0-isopropylidene-N6-methyladenosine (3). Under similar conditions, compound 2 gave 8-bromo-2′,3′-0-isopropylidene-N6-methyladenosine (4). The transformations 1 → 3 and 2 → 4 represent biomimetic models of in vivo N6-demethylation of antibiotic puromycin.  相似文献   

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6, 9-Deepoxy-6, 9-(phenylimino)-Δ 6, 8-prostaglandin I1 (U-60257) and its methyl ester (U-56467) are selective inhibitors of leukotriene C and D biosynthesis both invitro and in vivo. In this study, we demonstrated that the principal site of inhibition may be arachidonate 5-lipoxygenase, the initial enzyme of leukotriene biosynthesis. U-60257 and its methyl ester block LTB4 synthesis in human peripheral neutrophils with an ID50 of 1.8 and 0.42 μM respectively. This inhibitory action of U-60257 on neutrophil 5-lipoxygenase can be reduced or reversed by a high concentration of exogenous arachidonic acid. U-60257 at 100 μM has no apparent effect on the following enzymes. 1) cyclooxygenase of sheep vesicular gland or human platelets; 2) 12-lipoxygenase of human platelets and 3) soybean 15-lipoxygenase. Thus, we conclude that U-60257 and its methyl ester potent and selective inhibitors of arachidonate 5-lipoxygenase.  相似文献   

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Both the 5α, 6α- and 5β, 6β-dichloromethylene adducts (2a and 2b) of 3β-acetoxy-5-androsten-17-one (1) are produced when the latter is exposed to dichlorocarbene generated from chloroform and base by Phase Transfer Catalysis using ultrasound as a means of agitation. The 1H NMR substituent effects of 5α, 6α- and 5β, 6β-dichloromethylene on the angular methyl groups (Zürcher values) are given. The 13C NMR spectra for both compounds are presented and discussed.  相似文献   

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The IL-6-amplifier first was discovered as a synergistic activation mechanism for NF-κB/STAT3 in type 1 collagen(+) cells. This process is marked by the hyperinduction of chemokines and subsequent local inflammation that leads to autoimmune diseases. In this study, we show that IL-6 amplifier activation in grafts plays important roles in allogeneic graft rejection by using a tracheal heterotopic transplantation model that includes bronchiolitis obliterans, a pathological marker for chronic rejection. IL-6, epidermal growth factor, and IFN-γ all stimulate IL-6 amplifier activation, whereas CCL2, a chemotactic factor for Th1 cells, was one of the amplifier's main targets. Interestingly, IFN-γ hyperinduced CCL2 in type 1 collagen(+) cells via the IL-6 amplifier at least in vitro. In addition, we detected IL-6, CCL2, phospho-STAT3, and phospho-NF-κB in epithelial type 1 collagen(+) cells of allogeneic tracheal grafts. These results show that IL-6 amplifier activation in grafts plays a critical role for graft rejection responses after allogeneic transplantation, including chronic rejection. From these results, we consider whether the IL-6 amplifier in grafts might be a valuable therapeutic target for the prevention of transplant rejection, including chronic rejection.  相似文献   

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Abstract

This is a scanned image of the original Editorial Board page(s) for this issue  相似文献   

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Background

Little is known about the immunopathogenesis of Chikungunya virus. Circulating levels of immune mediators and growth factors were analyzed from patients infected during the first Singaporean Chikungunya fever outbreak in early 2008 to establish biomarkers associated with infection and/or disease severity.

Methods and Findings

Adult patients with laboratory-confirmed Chikungunya fever infection, who were referred to the Communicable Disease Centre/Tan Tock Seng Hospital during the period from January to February 2008, were included in this retrospective study. Plasma fractions were analyzed using a multiplex-microbead immunoassay. Among the patients, the most common clinical features were fever (100%), arthralgia (90%), rash (50%) and conjunctivitis (40%). Profiles of 30 cytokines, chemokines, and growth factors were able to discriminate the clinical forms of Chikungunya from healthy controls, with patients classified as non-severe and severe disease. Levels of 8 plasma cytokines and 4 growth factors were significantly elevated. Statistical analysis showed that an increase in IL-1β, IL-6 and a decrease in RANTES were associated with disease severity.

Conclusions

This is the first comprehensive report on the production of cytokines, chemokines, and growth factors during acute Chikungunya virus infection. Using these biomarkers, we were able to distinguish between mild disease and more severe forms of Chikungunya fever, thus enabling the identification of patients with poor prognosis and monitoring of the disease.  相似文献   

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Glucose 6-phosphate dehydrogenase (G6PD) deficiency is the most common defect of red blood cells. Although some different laboratory techniques or methods are employed for the biochemical screening, a strict relationship between biochemists, clinicians, and molecular biologists is necessary for a definitive diagnosis. This article represents an overview on the current laboratory tests finalized to the screening or to the definitive diagnosis of G6PD-deficiency, underlying the problems regarding the biochemical and molecular identification of heterozygote females other than those regarding the standardization of the clinical and laboratory diagnostic procedures. Finally, this review is aimed to give a flow-chart for the complete diagnostic approach of G6PD-deficiency.  相似文献   

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A total of 17 N,N'-dialkyl-N,N'-dimethyl-1,6-hexanediamine dioxides were tested for activity against three microorganisms. A relationship was found between the length of the alkyl substituent and antimicrobial activity.  相似文献   

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