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1.
The growth response ofCalopogonium caeruleum, a leguminous covercrop in plantation agriculture, to inoculation with two vesicular-arbuscular mycorrhizal (VAM) fungi was investigated in five phosphorus (P)-deficient soils supplied with various levels of rock phosphate. Significant shoot yield increases over the uninoculated controls were obtained in most sterilised or unsterilised soils at all applied P levels, although the inoculant VAM fungi differed in their effectiveness in the soils used. Responses in mycorrhizal root infections, P and nitrogen (N) concentrations in tops and plant nodulation varied. The results are discussed in relation to the edaphic environment of the mycorrhizal association.  相似文献   
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Summary We describe a new solid-phase strategy for the selective reduction of the C=N bond in peptide oximes using a trialkylsilane in trifluoroacetic acid. The reduction is performed directly on the resin-bound peptide, with concomitant cleavage of the peptide from the resin and deblocking of protected side chains.  相似文献   
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International Journal of Peptide Research and Therapeutics - Overexpression of ERBBB family of receptors (ERBB1, ERBB2, ERBB3 and ERBB4) has been found to be hyper-activated in a number of...  相似文献   
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Background

Giardia duodenalis infection and malnutrition are still considered as public health problems in many developing countries especially among children in rural communities. This study was carried out among Aboriginal (Orang Asli) primary schoolchildren in rural peninsular Malaysia to investigate the burden and the effects of Giardia infection on growth (weight and height) of the children.

Methods/Findings

Weight and height of 374 children aged 7–12 years were assessed before and after treatment of Giardia infection. The children were screened for Giardia parasite using trichrome staining technique. Demographic and socioeconomic data were collected via face-to-face interviews using a pre-tested questionnaire. Overall, 22.2% (83/374) of the children were found to be infected with Giardia. Nutritional status of children was assessed and the results showed that the mean weight and height were 23.9 kg (95% CI = 23.3, 24.5) and 126.6 cm (95% CI = 125.6, 127.5), respectively. Overall, the prevalence of severe underweight, stunting and wasting were 28.3%, 23.8% and 21.0%, respectively. Multiple linear regression analyses showed sex, Giardia infection and household monthly income as the significant determinants of weight while sex and level of mother''s education were the significant determinants of height. Weight and height were assessed at 3 and 6 months after treatment of Giardia infection. It was found that Giardia infection has a significant association with the weight of children but not with height.

Conclusions/Significance

This study reveals high prevalence of Giardia infection and malnutrition among Aboriginal children in rural Malaysia and clearly highlights an urgent need to identify integrated measures to control these health problems in the rural communities. Essentially, proper attention should be given to the control of Giardia infection in Aboriginal communities as this constitutes one of the strategies to improve the nutritional status of Aboriginal children.  相似文献   
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We investigated leptin effects on lymphocyte interactions with hepatic-stellate-cells (HSCs). Leptin showed pro-fibrotic effects on HSCs with oxidative status imbalance.In co-cultures, leptin activates HSCs and consequently adhered HCV-lymphocytes more than healthy ones. Leptin also increased healthy and HCV lymphocyte proliferations; increased their reactive-oxygen-species; decreased antioxidants (reduced-glutathione) levels while inhibited apoptosis only of HCV-lymphocytes. The leptin-treated HCV-lymphocytes activated HSCs, increase interleukin-4 while decreased their apoptosis.Leptin-receptor-deficient (dbdb)-HSCs did not adhere lymphocytes. db/db-lymphocytes however showed fewer adherences to HSCs when compared to WT-counterparts.This study presents immune and oxidative modulatory effects of leptin on lymphocytes and their consequent interaction with HSCs.  相似文献   
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Immunoaffinity separation of large multivalent species such as viruses is limited by the stringent elution conditions necessary to overcome their strong and highly avid interaction with immobilized affinity ligands on the capture surface. Here we present an alternate strategy that harnesses the avidity effect to overcome this limitation. Red clover necrotic mosaic virus (RCNMV), a plant virus relevant to drug delivery applications, was chosen as a model target for this study. An RCNMV binding protein (RBP) with modest binding affinity (KD ~100 nM) was generated through mutagenesis of the Sso7d protein from Sulfolobus solfataricus and used as the affinity ligand. In our separation scheme, RCNMV is captured by a highly avid interaction with RBP immobilized on a nickel surface through a hexahistidine (6xHis) tag. Subsequently, disruption of the multivalent interaction and release of RCNMV is achieved by elution of RBP from the nickel surface. Finally, RCNMV is separated from RBP by exploiting the large difference in their molecular weights (~8 MDa vs. ~10 kDa). Our strategy not only eliminates the need for harsh elution conditions, but also bypasses chemical conjugation of the affinity ligand to the capture surface. Stable non‐antibody affinity ligands to a wide spectrum of targets can be generated through mutagenesis of Sso7d and other hyperthermophilic proteins. Therefore, our approach may be broadly relevant to cases where capture of large multivalent species from complex mixtures and subsequent release without the use of harsh elution conditions is necessary. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013  相似文献   
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Background

Peripheral artery disease (PAD) is an important global health problem and contributes to notable proportion of morbidity and mortality. This particular manifestation of systemic atherosclerosis is largely under diagnosed and undertreated. For sustainable preventive strategies in a country, it is mandatory to identify country-specific risk factors. We intended to assess the risk factors of PAD among adults aged 40–74 years.

Methods

This case control study was conducted in 2012–2013 in Sri Lanka. Seventy-nine cases and 158 controls in the age group of 40–74 years were selected for the study in order to have case to control ratio 1:2. The criterion for selecting cases and control was based on Ankle brachial pressure index (ABPI). Cases were selected from those who had ABPI 0.85 or less (ABPI ≤0.85) in either lower limb. Controls were selected from those ABPI score between 1.18 and 1.28 in both lower limbs. Only newly identified individuals with PAD were selected as cases. Controls were selected from the same geographical location and within the 5 year age group as cases.

Results

The history of diabetes mellitus more than 10 years (OR 5.8, 95% CI 2.2–14.2), history of dyslipidemia for more than 10 years (OR 4.9, 95% CI 2.1–16.2), history of hypertension for more than 10 years (OR 3.8, 95% CI 1.8–12.7) and smoking (OR 2.9, 95% CI 1.2–6.9), elevated HsCRP (OR 3.7, 95% CI 1.2–12.0) and hyperhomocysteinemia (OR 3.0, 95% CI 1.1–8.1) were revealed as country specific significant risk factor of PAD.

Conclusions

Diabetes mellitus, hypertension, dyslipidemia, smoking as well as elevated homocysteine and HsCRP found as risk factors of PAD. Longer the duration or higher level exposure to these risk factors has increased the risk of PAD. These findings emphasis the need for routine screening of PAD among patients with the identified risk factors.
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