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In this study, the diversity of Plasmodium vivax populations circulating in Pakistan and Iran has been investigated by using circumsporozoite protein (csp) and merozoite surface proteins 1 and 3α (msp-1 and msp-3α) genes as genetic markers. Infected P. vivax blood samples were collected from Pakistan (n = 187) and Iran (n = 150) during April to October 2008, and were analyzed using nested-PCR/RFLP and sequencing methods. Genotyping pvmsp-1 (variable block 5) revealed the presence of type 1, type 2 and recombinant type 3 allelic variants, with type 1 predominant, in both study areas. The sequence analysis of 33 P. vivax isolates from Pakistan and 30 from Iran identified 16 distinct alleles each, with one allele (R-8) from Iran which was not reported previously. Genotyping pvcsp gene also showed that VK210 type is predominant in both countries. Moreover, based on the size of amplified fragment of pvmsp-3α, three major types: type A (1800 bp), type B (1500 bp) and type C (1200 bp), were distinguished among the examined isolates that type A was predominant among Pakistani (72.7%) and Iranian (77.3%) parasites. PCR/RFLP products of pvmsp-3α with HhaI and AluI have detected 40 and 39 distinct variants among Pakistani and Iranian examined isolates, respectively. Based on these three studied genes, the rate of combined multiple genotypes were 30% and 24.6% for Pakistani and Iranian P. vivax isolates, respectively. These results indicate an extensive diversity in the P. vivax populations in both studies.  相似文献   
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Stressful housing conditions like social isolation have been shown to profoundly affect the physiology and health of various organisms which is rarely addressed in fish species. In the present study, we used a shoaling species, zebrafish, to investigate the stress reactivity of grouped and individually housed fish. We also hypothesized if isolation is a stressful condition may disrupt growth performance and innate immune response of individuals. To this end, fish were housed individually (social isolated treatment) or in groups of five fish (control treatment) for 60 days. Growth indices of fish were not affected by social isolation. Sixty-day social isolation did insignificant effect on baseline cortisol levels of specimens; however, individually housed zebrafish showed lower plasma cortisol to chasing stress than the control grouped fish. On the contrary, exposure to predator caused higher cortisol levels in social isolated fish. Serum lysozyme activity of isolated individuals was significantly lower than control fish, but activity of serum complement remained unchanged. Our results represent evidences that zebrafish experienced social isolation showed broad changes in physiological and immunological functions which may affect the quality of life.  相似文献   
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Increasing evidence supports the existence of variations in the association of plant roots with symbiotic fungi that can improve plant growth and inhibit pathogens. However, it is unclear whether intraspecific variations in the symbiosis exist among plant cultivars and if they can be used to improve crop productivity. In this study, we determined genotype-specific variations in the association of chickpea roots with soil fungal communities and evaluated the effect of root mycota on crop productivity. A 2-year field experiment was conducted in southwestern Saskatchewan, the central zone of the chickpea growing region of the Canadian prairie. The effects of 13 cultivars of chickpea, comprising a wide range of phenotypes and genotypes, were tested on the structure of root-associated fungal communities based on internal transcribed spacer (ITS) and 18S rRNA gene markers using 454 amplicon pyrosequencing. Chickpea cultivar significantly influenced the structure of the root fungal community. The magnitude of the effect varied with the genotypes evaluated, and effects were consistent across years. For example, the roots of CDC Corrine, CDC Cory, and CDC Anna hosted the highest fungal diversity and CDC Alma and CDC Xena the lowest. Fusarium sp. was dominant in chickpea roots but was less abundant in CDC Corrine than the other cultivars. A bioassay showed that certain of these fungal taxa, including Fusarium species, can reduce the productivity of chickpea, whereas Trichoderma harzianum can increase chickpea productivity. The large variation in the profile of chickpea root mycota, which included growth-promoting and -inhibiting species, supports the possibility of improving the productivity of chickpea by improving its root mycota in chickpea genetic improvement programs using traditional breeding techniques.  相似文献   
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There is worldwide interest in developing algal biofuel. One main reason for the lack of success so far in producing a sustainable transport fuel from microalgae is the high cost of biomass processing, especially dewatering and oil extraction. There is also a significant cost involved in the energy content of the nutrient fertilisers required for biomass production. Non-destructive oil extraction or “milking” from algae biomass has the potential to bypass all of these hurdles. Using a “milking” strategy means that there would be no need for (a) biomass dewatering, (b) breaking cells for oil extraction and (c) addition of nutrients to the culture, resulting in a significant reduction in energy and fertiliser cost involved in production of biofuel from algae. We make use of the natural tendency of Botryococcus to produce external hydrocarbon in the extracellular matrix. In current study, we showed that external hydrocarbon from Botryococcus braunii BOT-22 can be non-destructively extracted using n-heptane (optimum contact time with n-heptane?=?20 min). We were able to recover almost the entire de novo-produced external hydrocarbons at 5- and 11-day intervals when the culture was maintained with or without 1 % CO2 addition, respectively. This repeated non-destructive extraction of external hydrocarbon of B. braunii was possible for up to 70 days when 1 % CO2 was supplied to the culture. When CO2 was limited, a 70 % lower external hydrocarbon productivity was achieved using the same process. Although the productivity of external hydrocarbon of 9.33 mg L?1 day?1 of the “milked” culture is low in these un-optimised cultures, it was 1.3?±?0.2-fold higher compared with that of a conventional semicontinuous culture, showing the potential of this method.  相似文献   
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International Journal of Peptide Research and Therapeutics - Shigella spp. causes severe diarrhea and dysenteric disease, which known as shigellosis. Until now, no licensed vaccine is available for...  相似文献   
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Isomeric molecules present a challenge for analytical resolution and quantification, even with MS-based detection. The eight aminobutyric acid (ABA) isomers are of interest for their various biological activities, particularly γ-aminobutyric acid (GABA) and the d- and l-isomers of β-aminoisobutyric acid (β-AIBA; BAIBA). This study aimed to investigate LC-MS/MS-based resolution of these ABA isomers as their Marfey's (Mar) reagent derivatives. HPLC was able to separate three Mar-ABA isomers l-β-ABA (l-BABA), and l- and d-α-ABA (AABA) completely, with three isomers (GABA, and d/l-BAIBA) in one chromatographic cluster, and two isomers (α-AIBA (AAIBA) and d-BABA) in a second cluster. Partially separated cluster components were deconvoluted using Gaussian peak fitting except for GABA and d-BAIBA. MS/MS detection of Marfey's derivatized ABA isomers provided six MS/MS fragments, with substantially different intensity profiles between structural isomers. This allowed linear deconvolution of ABA isomer peaks. Combining HPLC separation with linear and Gaussian deconvolution allowed resolution of all eight ABA isomers. Application to human serum found a substantial level of l-AABA (13 μM), an intermediate level of l-BAIBA (0.8 μM), and low but detectable levels (<0.2 μM) of GABA, l-BABA, AAIBA, d-BAIBA, and d-AABA. This approach should be useful for LC-MS/MS deconvolution of other challenging groups of isomeric molecules.  相似文献   
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The low-molecular-weight compound JRC-II-191 inhibits infection of HIV-1 by blocking the binding of the HIV-1 envelope glycoprotein gp120 to the CD4 receptor and is therefore an important lead in the development of a potent viral entry inhibitor. Reported here is the use of two orthogonal screening methods, gold docking and ROCS shape-based similarity searching, to identify amine-building blocks that, when conjugated to the core scaffold, yield novel analogs that maintain similar affinity for gp120. Use of this computational approach to expand SAR produced analogs of equal inhibitory activity but with diverse capacity to enhance viral infection. The novel analogs provide additional lead scaffolds for the development of HIV-1 entry inhibitors that employ protein-ligand interactions in the vestibule of gp120 Phe 43 cavity.  相似文献   
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White adipose tissue (WAT) is the source of pro- and anti-inflammatory cytokines and we have recently shown that this tissue is a major source of the anti-inflammatory interleukin (IL)-1 receptor antagonist (IL-1Ra). We now aimed at identifying additional adipose-derived cytokines, which might serve as regulators of IL-1Ra. We demonstrate here for the first time that the antiinflammatory cytokine IL-10 is secreted by human WAT explants and that it is up-regulated by LPS and TNF-alpha in vitro, as well as in obesity in humans (2- and 6-fold increase in subcutaneous and visceral WAT, respectively) and rodents (4-fold increase).  相似文献   
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