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21.
In vitro antiviral activity of plant extracts on goatpox virus replication   总被引:2,自引:0,他引:2  
Four plants having known medicinal properties were screened for inhibition of goatpox virus (GTPV) replication in vitro. Of the 4 plants, extract of Acacia arabica (Babul) and Eugenia jambolana (Jamun) leaves had inhibition (%) 99.70 and 99.92 at their maximum non toxic concentrations, 99.93 +/- 0.38 and 1999.73 +/- 0.50 microg/ml, respectively in all cytopathic effect (CPE) inhibition assays. Inhibition of GTPV virus replication was further confirmed by PCR and SYBR Green based quantitative real-time QPCR assays specific for GTPV. Results indicated that the extract of Acacia arabica and Eugenia jambolana leaves inhibited GTPV replication in vitro.  相似文献   
22.
The cytosol of hepatopancreas was prepared from the freshwater prawn Macrobrachium malcolmsonii, and optimal assay conditions, i.e., concentration of substrate, pH, and temperature, were determined to measure basal activities and kinetic constants of catalase activity. The properties of catalase were examined in M. macolmsonii, because quantitative data on catalase are limited in crustacean species. The optimal pH for catalase was 7.0. The activation energy was 3.55 Kcal/mol and energy inhibition value was 5.16 Kcal/mol. The value of energy inhibition is higher than that of energy activation. This may be due to inhibition of catalase by some substrate other than H2O2. A Km of 66.6 mM was also determined from various concentrations of substrate.  相似文献   
23.
Horsegram [Macrotyloma uniflorum (Lam.) Verdc.) is an important grain legume and fodder crop in India. Information on root nodule endosymbionts of this legume in India is limited. In the present study, 69 isolates from naturally occurring root nodules of horsegram collected from two agro-eco-climatic regions of South India was analyzed by generation rate, acid/alkali reaction on YMA medium, restriction fragment length polymorphism analysis of 16S-23S rDNA intergenic spacer region (IGS), and sequence analyses of IGS and housekeeping genes glnII and recA. Based on the rDNA IGS RFLP by means of three restriction enzymes rhizobia were grouped in five clusters (I–V). By sequence analysis of 16S-23S rDNA IGS identified genotypes of horsegram rhizobia were distributed into five divergent lineages of Bradyrhizobium genus which comprised (I) the IGS type IV rhizobia and valid species B. yuanmingense, (II) the strains of IGS type I and Bradyrhizobium sp. ORS 3257 isolated from Vigna sp., (III) the strains of the IGS type II and Bradyrhizobium sp. CIRADAc12 from Acacia sp., (IV) the IGS type V strains and Bradyrhizobium sp. genospecies IV, and (V) comprising genetically distinct IGS type III strains which probably represent an uncharacterized new genomic species. Nearly, 87% of indigenous horsegram isolates (IGS types I, II, III, and V) could not be related to any other species within the genus Bradyrhizobium. Phylogeny based on housekeeping glnII and recA genes confirmed those results found by the analysis of the IGS sequence. All the isolated rhizobia nodulated Macrotyloma sp. and Vigna spp., and only some of them formed nodules on Arachis hypogeae. The isolates within each IGS type varied in their ability to fix nitrogen. Selection for high symbiotic effective strains could reward horsegram production in poor soils of South India where this legume is largely cultivated.  相似文献   
24.
Across several cohorts, human immunodeficiency virus type 1 (HIV-1) Gag- and Env-specific CD8(+) T lymphocyte (CTL) responses have demonstrated inverse and positive correlations, respectively, to viremia. The mechanism has been proposed to be superior antiviral activity of Gag-specific CTLs in general. Addressing this hypothesis, we created two HIV-1 constructs with an epitope translocated from Gag (SLYNTVATL, SL9) to Env, thereby switching the protein source of the epitope. A virus expressing SL9 in Env was similar to the original virus in susceptibility to SL9-specific CTLS. This finding suggests that Env targeting is not intrinsically inferior to Gag targeting for CTL antiviral activity.  相似文献   
25.
26.

Background

Older patients are at an increased risk of developing adverse drug reactions (ADR). Of particular concern are the oldest old, which constitute an increasingly growing population. Having a validated clinical tool to identify those older patients at risk of developing an ADR during hospital stay would enable healthcare staff to put measures in place to reduce the risk of such an event developing. The current study aimed to (1) develop and (2) validate an ADR risk prediction model.

Methods

We used a combination of univariate analysis and multivariate binary logistic regression to identify clinical risk factors for developing an ADR in a population of older people from a UK teaching hospital. The final ADR risk model was then validated in a European population (European dataset).

Results

Six-hundred-ninety patients (median age 85 years) were enrolled in the development stage of the study. Ninety-five reports of ADR were confirmed by independent review in these patients. Five clinical variables were identified through multivariate analysis and included in our final model; each variable was attributed a score of 1. Internal validation produced an AUROC of 0.74, a sensitivity of 80%, and specificity of 55%. During the external validation stage the AUROC was 0.73, with sensitivity and specificity values of 84% and 43% respectively.

Conclusions

We have developed and successfully validated a simple model to use ADR risk score in a population of patients with a median age of 85, i.e. the oldest old. The model is based on 5 clinical variables (≥8 drugs, hyperlipidaemia, raised white cell count, use of anti-diabetic agents, length of stay ≥12 days), some of which have not been previously reported.  相似文献   
27.
Live attenuated vaccines are of great value for preventing infectious diseases. They represent a delicate compromise between sufficient colonization-mediated adaptive immunity and minimizing the risk for infection by the vaccine strain itself. Immune defects can predispose to vaccine strain infections. It has remained unclear whether vaccine safety could be improved via mutations attenuating a vaccine in immune-deficient individuals without compromising the vaccine''s performance in the normal host. We have addressed this hypothesis using a mouse model for Salmonella diarrhea and a live attenuated Salmonella Typhimurium strain (ssaV). Vaccination with this strain elicited protective immunity in wild type mice, but a fatal systemic infection in immune-deficient cybb −/− nos2 −/− animals lacking NADPH oxidase and inducible NO synthase. In cybb −/− nos2 −/− mice, we analyzed the attenuation of 35 ssaV strains carrying one additional mutation each. One strain, Z234 (ssaV SL1344_3093), was >1000-fold attenuated in cybb −/− nos2 −/− mice and ≈100 fold attenuated in tnfr1 −/− animals. However, in wt mice, Z234 was as efficient as ssaV with respect to host colonization and the elicitation of a protective, O-antigen specific mucosal secretory IgA (sIgA) response. These data suggest that it is possible to engineer live attenuated vaccines which are specifically attenuated in immuno-compromised hosts. This might help to improve vaccine safety.  相似文献   
28.
Photosynthetic microalgae are of burgeoning interest in the generation of commercial bioproducts. Microalgae accumulate high lipid content under adverse conditions, which in turn compromise their growth and hinder their commercial potential. Hence, it is necessary to engineer microalgae to mitigate elevated lipid accumulation and biomass. In this study, we identified acetyl-CoA carboxylase (ACCase) in oleaginous microalga Phaeodactylum tricornutum (PtACC2) and expressed constitutively in the chloroplast to demonstrate the potential of chloroplast engineering. Molecular characterization of transplastomic microalgae revealed that PtACC2 was integrated, transcribed and expressed successfully, and localized in the chloroplast. Enzymatic activity of ACCase was elevated by 3.3-fold, and the relative neutral lipid content increased substantially by 1.77-fold, and lipid content reached up to 40.8% of dry weight. Accordingly, the number and size of oil bodies markedly increased. Fatty acid profiling showed that the content of monounsaturated fatty acids increased, while polyunsaturated fatty acids decreased. This method provides a valuable genetic engineering toolbox for microalgal bioreactors with industrial significance.  相似文献   
29.
Vascular calcification due to elevated phosphate levels is the major contributor of cardiovascular dysfunction. The oxidative stress and gene expression events modulate the transdifferentiation of vascular smooth muscle cells into osteogenic phenotype. This present study intends to evaluate the dose-dependent effect of diosgenin, an antioxidant on high phosphate induced vascular calcification in adenine-induced chronic renal failure rats. High phosphate environment causes elevated calcium accumulation with related histological changes and alkaline phosphatase activity in aorta. Further it downregulates the activity of enzymatic antioxidants and elevates the level of lipid peroxidative markers. Moreover, the renal failure leads to reduced nitric oxide production. But, treatment with diosgenin at a dose of 10, 20, and 40 mg/kg given via oral gavages causes reversion of all the above events in a dose-dependent manner. The highest dose has shown more potential activity than other two doses, which has the ability to protect the alteration of liver markers and red blood cell antioxidant system without any adverse effects and it does not alter the kidney associated changes too. Finally, the Fourier transform infrared spectroscopy study strongly supports its ability to protect the macromolecules from oxidative stress. All the above evidences show that diosgenin has overall benefits against renal failure-induced vascular calcification-associated oxidative stress.  相似文献   
30.
The synthesis, structure and spectral and redox properties of the copper(II) complexes [Cu(pmtpm)Cl2] (1) and [Cu(pmtpm)2](ClO4)2 (6), where pmtpm is the linear tridentate ligand 2-pyridyl-N-(2′-methylthiophenyl)methyleneimine containing a thioether and two pyridine donors, are described. Also, the mixed ligand complexes [Cu(pmtpm)(diimine)](ClO4)2 (2-5), where the diimine is 2,2′-bipyridine (bpy) (2), 1,10-phenanthroline (phen) (3), 2,9-dimethyl-1,10-phenanthroline (2,9-dmp) (4) or dipyrido-[3,2-d:2′,3′-f]-quinoxaline (dpq) (5), have been isolated and studied. The X-ray crystal structures of the complexes 1, [Cu(pmtpm)(2,9-dmp)](ClO4)24 and 6 have been successfully determined. The complex 1 possesses a trigonal bipyramidal distorted square based pyramidal (TBDSBP) coordination geometry in which three corners of the square plane are occupied by two nitrogens and thioether s of pmtpm ligand and the remaining equatorial and the axial positions by two chloride ions. The complex 4 contains a CuN4S chromophore also with a TBDSBP coordination geometry in which two nitrogens and the thioether sulfur of pmtpm ligand occupy three corners of the square plane. One of the two nitrogens of 2,9-dmp ligand is equatorially coordinated and the other axially to copper. On the other hand, the complex 6 is found to possess a square based pyramidal distorted trigonal bipyramidal (SPDTBP) coordination geometry. The CuN2S trigonal plane in it is comprised of the pyridine and imine nitrogens and the thioether sulfur of the pmtpm ligand. The pyridine nitrogens of the ligand occupy the axial positions and the second thioether sulfur remains uncoordinated. On long standing in acetonitrile solution the mixed ligand complexes 2 and 3 undergo ligand disproportionation to provide the corresponding bis-complexes of bpy and phen, respectively, and 6. The electronic and EPR spectral parameters and the positive redox potential of complex 4 are consistent with the equatorial location of the thioether sulfur in the square-based coordination geometry around copper(II). On the other hand, the higher g and lower A values and lower E1/2 values for the complexes 2, 3 and 5 are consistent with the axial coordination of the thioether sulfur. Also, the Cu(II)/Cu(I) redox potentials increase with increase in number of aromatic rings of the diimine ligand. The steric and electronic effects of the bidentate diimine ligands in orienting the thioether coordination to axial or equatorial position are discussed.  相似文献   
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