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1.
Experimental studies have identified a complex link between neurodegeneration, β-amyloid (Aβ) and calcium homeostasis. Here we asked whether early phase β-amyloid pathology in transgenic hAPPSL mice exaggerates the ischemic lesion and remote secondary pathology in the thalamus, and whether a non-selective calcium channel blocker reduces these pathologies. Transgenic hAPPSL (n = 33) and non-transgenic (n = 30) male mice (4–5 months) were subjected to unilateral cortical photothrombosis and treated with the non-selective calcium channel blocker bepridil (50 mg/kg, p.o., once a day) or vehicle for 28 days, starting administration 2 days after the operation. Animals were then perfused for histological analysis of infarct size, Aβ and calcium accumulation in the thalamus. Cortical photothrombosis resulted in a small infarct, which was associated with atypical Aβ and calcium accumulation in the ipsilateral thalamus. Transgenic mice had significantly smaller infarct volumes than non-transgenic littermates (P<0.05) and ischemia-induced rodent Aβ accumulation in the thalamus was lower in transgenic mice compared to non-transgenic mice (P<0.01). Bepridil decreased calcium load in the thalamus (P<0.01). The present data suggest less pronounced primary and secondary pathology in hAPPSL transgenic mice after ischemic cortical injury. Bepridil particularly decreased calcium pathology in the thalamus following ischemia.  相似文献   
2.
Lymphoid cell subclasses in rejecting renal allograft in the rat   总被引:4,自引:0,他引:4  
We have quantitated the frequency of lymphoid cell subsets in rejecting renal allografts and in the spleen of the allograft recipient during drug-unmodified rejection in the rat. The number of inflammatory (white) cells in the graft was approximately similar to the number of white cells responding to the allograft in the recipient spleen. The inflammatory population of the graft consisted of lymphoid cells and mononuclear phagocytes, with increasing numbers of macrophages toward the end of rejection. Analysis of allograft cellular dispersates with monoclonal antibodies directed to the lymphoid cell subsets demonstrated that although the majority of allograft-infiltrating lymphocytes were T cells, a sizable B-cell proliferation and immunoglobulin synthesis was associated with the inflammatory response of rejection. Within the T-cell subset, the T suppressor/killer cells predominated in the graft whereas the predominant lymphoid cell subset responding to the allograft in the recipient spleen was the T helper cell.  相似文献   
3.
Extracelluar lipase activity was detected in a culture of Pseudomonas strain Ptm+ growing on hexachlorocyclohexane. Lipase activity was associated with growth of the bacterium and reached a peak at early idiophase (22 h). Following the lipase activity, bioemulsifier was produced, with maximum activity at mid-idiophase (32 h). The extracellular lipase is probably involved in the extracellular synthesis of the bioemulsifier in the culture broth.  相似文献   
4.
Expression of Rhizobium galegae common nod clones in various backgrounds.   总被引:1,自引:0,他引:1  
The cosmid clone pRg30, carrying common nodulation genes of Rhizobium galegae HAMBI 1174, and pRg33, a subclone of pRg30 that contains a 5.7-kb ClaI insert carrying nodDABC were conjugated into various Rhizobium nod- mutant strains and into a Ti plasmid-cured Agrobacterium tumefaciens. Complementation and expression of the nodABC genes of R. galegae were studied by following microscopically the infection process and the nodulation on different test plants. The nodABC genes of R. galegae complemented the nod- strains of other Rhizobium species. The presence of extra copies of common nod genes in the homologous R. galegae nodABC- strain induced an increased nodulation on Galega orientalis. However, the inserts of R. galegae in pRg30 and pRg33 do not carry sufficient genetic information for normal nodulation of test plants in an Agrobacterium background, because the Agrobacterium transconjugants induced root hair deformation on Galega plants, but no infection threads were detected and nodulelike structures developed only at low frequency. The Agrobacterium carrying the nodDABC of R. galegae did not cause the root hairs of Medigo sativa to deform.  相似文献   
5.
In present studies, the new optical sensing platform based on optical planar waveguide (OPWG) for sucrose estimation was reported. An evanescent-wave biosensor was designed by using novel agarose–guar gum (AG) biopolymer composite sol–gel with entrapped enzymes (acid invertase (INV) and glucose oxidase (GOD)). Partially purified watermelon invertase isolated from Citrullus vulgaris fruit (specific activity 832 units mg−1) in combination with GOD was physically entrapped in AG sol–gel and cladded on the surface of optical planar waveguide. Na+–K+ ion-exchanged glass optical waveguides were prepared and employed for the fabrication of sucrose biosensor. By addressing the enzyme modified waveguide structure with, the optogeometric properties of adsorbed enzyme layer (12 μm) at the sensor solid–liquid interface were studied. The OPWG sensor with short response time (110 s) was characterized using the 0.2 M acetate buffer, pH 5.5. The fabricated sucrose sensor showed concentration dependent linear response in the range 1 × 10−10 to 1 × 10−6 M of sucrose. Lower limit of detection of this novel AG–INV–GOD cladded OPWG sensor was found to be 2.5 × 10−11 M sucrose, which indicates that the developed biosensor has higher sensitivity towards sucrose as compared to earlier reported sensors using various transducer systems. Biochips when stored at room temperature, showed high stability for 81 days with 80% retention of original sensitivity. These sucrose sensing biochips showed good operational efficiency for 10 cycles. The proper confinement of acid invertase and glucose oxidase in hydrogel composite was confirmed by scanning electron microscopy (SEM) images. The constructed OPWG sensor is versatile, easy to fabricate and can be used for sucrose measurements with very high sensitivity.  相似文献   
6.
At northern latitudes a rise in atmospheric humidity and precipitation is predicted as a consequence of global climate change. We studied several growth and functional traits of hybrid aspen (Populus tremula L.×P. tremuloides Michx.) in response to elevated atmospheric humidity (on average 7% over the ambient level) in a free air experimental facility during three growing seasons (2008-2010) in Estonia, which represents northern temperate climate (boreo-nemoral zone). Data were collected from three humidified (H) and three control (C) plots, and analysed using nested linear models. Elevated air humidity significantly reduced height, stem diameter and stem volume increments and transpiration of the trees whereas these effects remained highly significant also after considering the side effects from soil-related confounders within the 2.7 ha study area. Tree leaves were smaller, lighter and had lower leaf mass per area (LMA) in H plots. The magnitude and significance of the humidity treatment effect - inhibition of above-ground growth rate - was more pronounced in larger trees. The lower growth rate in the humidified plots can be partly explained by a decrease in transpiration-driven mass flow of NO(3) (-) in soil, resulting in a significant reduction in the measured uptake of N to foliage in the H plots. The results suggest that the potential growth improvement of fast-growing trees like aspens, due to increasing temperature and atmospheric CO(2) concentration, might be smaller than expected at high latitudes if a rise in atmospheric humidity simultaneously takes place.  相似文献   
7.
Abstract

Myceliophthora thermophila encodes for large number of carbohydrate-active enzymes (CAZymes) involved in lignocellulosic biomass degradation. The mould was grown on rice straw in solid state fermentation at pH 5.0 and 45?°C that produced high levels of cellulolytic and xylanolytic enzymes i.e. 2218.12, 515.23, 478.23, 13.34?U/g DMR for xylanase, CMCase, FPase and β-glucosidase, respectively. The secretome analysis of M. thermophila BJAMDU5 by mass spectroscopy, described 124 different proteins with majority of CAZymes consisting of glycosyl hydrolases (GH), lytic polysaccharide mono-oxygenases (LPMO), carbohydrate esterases (CE) and polysaccharide lyases (PL). Furthermore, the enzyme cocktail of the mould was evaluated for hydrolysis of steam treated rice straw that produced 184.59?mg/g substrate reducing sugars after 24?h, which was used for production of bioethanol by using fast fermenting yeast Saccharomyces cerevisiae resulting in high production of bioethanol.  相似文献   
8.
Abstract

Concentrations of heavy metals (Cd, Co, Cr, Cu and Fe) in surface sediments and their partitioning behaviour between exchangeable, reducible (Fe-Mn oxide bound) and organic/residual phases of the sediments in a typical backwater system of Kerala, viz. the southern upstream part of Cochin Estuarine System (South India), have been studied. Spatial and temporal variations of trace metals are discussed with special reference to pH, dissolved oxygen, salinity, organic carbon and texture of sediment. Metal concentrations in the tide gated part of the estuary were found to be significantly higher when compared to metal concentrations reported from the unrestricted part of the Cochin estuarine system and also those from many of the unpolluted estuaries worldwide. The higher levels of heavy metals in the study area and their characteristic distribution and partitioning behaviour in the surficial sediments were attributed to the presence of a salinity barrier across the backwater system and also by the massive use of pesticides and chemical fertilizers in the vast area of agricultural land near the backwater system.  相似文献   
9.
Food action plans in many global cities articulate interest in multiple objectives including reducing in‐ and trans‐boundary environmental impacts (water, land, greenhouse gas (GHG)). However, there exist few standardized analytical tools to compare food system characteristics and actions across cities and countries to assess trade‐offs between multiple objectives (i.e., health, equity) with environmental outcomes. This paper demonstrates a streamlined model applied for analysis of four cities with varying characteristics across the United States and India, to quantify system‐wide water, energy/GHG, and land impacts associated with multiple food system actions to address health, equity, and environment. Baseline diet analysis finds key differences between countries in terms of meat consumption (Delhi 4; Pondicherry 16; United States 59, kg/capita/year), and environmental impact of processing of the average diet (21%, 19%, <1%, <1% of community‐wide GHG‐emissions for New York, Minneapolis, Delhi, and Pondicherry). Analysis of supply chains finds city average distance (food‐miles) varies (Delhi 420; Pondicherry 200; United States average 1,640 km/t‐food) and the sensitivity of GHG emissions of food demand to spatial variability of energy intensity of irrigation is greater in Indian than US cities. Analysis also finds greater pre‐consumer waste in India versus larger post‐consumer accumulations in the United States. Despite these differences in food system characteristics, food waste management and diet change consistently emerge as key strategies. Among diet scenarios, all vegetarian diets are not found equal in terms of environmental benefit, with the US Government's recommended vegetarian diet resulting in less benefit than other more focused targeted diet changes.  相似文献   
10.
The present study provides the first detailed early embryonic development of the Shalyni barb, Pethia shalynius (Yazdani & Talukdar, 1975), a vulnerable cyprinid fish occurring in streams and lentic waters of Meghalaya, northeast India. Induced spawning by synthetic hormone injection in May 2019 was conducted to a pair of mature female and male P. shalynius under controlled conditions in a well-aerated aquarium. Fertilized eggs were spherical, 0.75–0.80 mm (approx.) in diameter, transparent, unpigmented and non-adhesive. A total of 22 developmental stages could be categorized under seven broad periods, viz. the zygote, cleavage, blastula, gastrula, segmentation, pharyngula and hatchling. The first cleavage occurred at 15 min post fertilization (mpf), followed by blastulation at 01:23 hr post-fertilization (hpf), gastrulation at 04:20 hpf, initial somite formation at 07:00 hpf, and pharyngula period at 19:20 hpf, respectively. Embryos hatched between 26–27 hpf and the newly-hatched larvae ranged 2.2–2.5 mm in total length. For naturally-declining populations of this vulnerable fish species, inferences drawn from the present study will help provide a baseline data for its conservation and management, and aid the research fields of developmental biology, biotechnology, molecular biology as well as taxonomy of this species.  相似文献   
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