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1.
Excessive intake of essential elements agitates elemental homeostasis resulting in their heterogeneous distribution. Distraction of these elements in central nervous system (CNS) have been demonstrated in many neurological disorders, which are vital in generating free radicals, causing oxidative stress, and contributing to neuronal maladies. The developing CNS is highly vulnerable to environmental agents, including fluoride. Fluorosis is one such disorder ensued from excessive consumption of fluoride containing water and/or foods that poses a greater threat to the life. Present study offers perturbations caused by fluoride toxicity on the level of biometal and antioxidant homeostasis and their interactions. Pregnant Wistar rats were exposed to 100- and 200-ppm fluoride (F) in drinking water and controls with tap water. The pups born to them were used for the study. On 21st postnatal day, the concentration of fluoride, biometals, and oxidative stress markers were determined in discrete regions of CNS. The levels of fluoride, copper, and iron increased whereas manganese and zinc were decreased considerably. Among antioxidant enzymes, catalase, superoxide dismutase, and glutathione peroxidase were decreased and lipid peroxidation was increased with regional alterations. The correlation coefficient values among oxidative stress markers and biometals were either positive or negative and showed less significance during correlation. The results confirm that the fluoride provoked oxidative stress and biometal deformations are synergistic that successively governs the neuronal damage and developing CNS no longer prevents exacerbations of fluoride.  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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4.
Spermatogenesis is a complex and highly regulated process by which spermatogonial stem cells differentiate into spermatozoa. To better understand the molecular mechanisms of the process, the Cre/loxP system has been widely utilized for conditional gene knockout in mice. In this study, we generated a transgenic mouse line that expresses Cre recombinase under the control of the 2.5 kbp of the Prolactin family 3, subfamily b, member 1 (Prl3b1) gene promoter (Prl3b1‐cre). Prl3b1 was initially reported to code for placental lactogen 2 (PL‐2) protein in placenta along with increased expression toward the end of pregnancy. PL‐2 was found to be expressed in germ cells in the testis, especially in spermatocytes. To analyze the specificity and efficiency of Cre recombinase activity in Prl3b1‐cre mice, the mice were mated with reporter R26GRR mice, which express GFP ubiquitously before and tdsRed exclusively after Cre recombination. The systemic examination of Prl3b1‐cre;R26GRR mice revealed that tdsRed‐positive cells were detected only in the testis and epididymis. Fluorescence imaging of Prl3b1‐cre;R26GRR testes suggested that Cre‐mediated recombination took place in the germ cells with approximately 74% efficiency determined by in vitro fertilization. In conclusion, our results suggest that the Prl3b1cre mice line provides a unique resource to understand testicular germ‐cell development. genesis 54:389–397, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
5.
Aquaculture practices from sub-Saharan Africa are characterised by low production, owing to improper technology. Production can be increased through integrating fish farming with other existing on-farm activities, particularly livestock husbandry. We assessed the role of fish-poultry integration on all male Nile tilapia, Oreochromis niloticus growth performance, yields and economic benefits among smallholder farmers in sub-Saharan Africa, Tanzania. The study also compared phytoplankton species composition, abundance and biomass between the fish-poultry integration and non-integrated system. After 180 days of the experiment, all male O. niloticus cultured under fish-poultry integration exhibited significantly higher growth rates than those in the non-integrated system (p < 0.05). Gross fish yield (GFY), net fish yield (NFY) and net annual yields (NAY) obtained from fish-poultry integration were significantly higher than those from non-integrated system (p < 0.05). Partial enterprise budget analysis revealed that fish-poultry integration was more profitable than the non-integrated system. Moreover, fish-poultry integrated system produced significantly higher phytoplankton abundance and biomass than those from the non-integrated system. Results demonstrate that rural smallholder farmers can achieve higher growth rate, farm net yields and income by integrating all male O. niloticus with other on-farm activities than practising a stand-alone fish culture system.  相似文献   
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Methyl parathion induced alterations in the level of monoamines, viz. norepinephrine, dopamine and serotonin were studied in discrete regions of developing central nervous system of rat pups. A significant decrease in the level of monoamines noticed in methyl parathion toxicosis may be related to the altered neuronal activity and inefficiency, leading to depression and impairment in various behavioural activities. In contrast to AChE inhibition, monoamine oxidase (MAO) activity showed an increasing trend and it could cause deamination of catecholamines and accumulation of its metabolites. This suggests that an increased AChE inhibition may indirectly stimulate MAO activity in developing rat pups exposed to methyl parathion.  相似文献   
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Macrobrachium rosenbergii was experimentally challenged with Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus (XSV) to study the clearance of these viruses and consequent changes in various immunological parameters. The healthy animals were injected MrNV and XSV intramuscularly and various organ samples such as gill tissue, head soft tissue, pleopods and intestine were collected at different time intervals of 3, 5, 10, 15, 25, 50, 75 and 100 d post-infection (p.i.) to study the viral clearance. Tissue tropism and clearing of MrNV and XSV were confirmed by RT-PCR, nested RT-PCR and bioassay. These 2 viruses failed to cause mortality or clinical signs of disease in injected adult prawns during the experimental period of 100 days. The result of RT-PCR analysis revealed that all the organs showed positive for both viruses by single step RT-PCR on 3, 5 and 10 d p.i., positive by nested RT-PCR on 15 and 20 d p.i. and all the organs became negative at 25 d p.i. onwards. The viral inoculum prepared from the tissue of MrNV and XSV-injected M. rosenbergii at 3, 5, 10, 15 and 20 d p.i. caused 100% mortality in post-larvae of M. rosenbergii at 9, 8, 7, 10 and 10 d p.i., respectively whereas the inoculum prepared at 25, 50 and 100 d p.i. failed to cause significant mortality in post-larvae of prawn. Immunological parameters such as proPO, superoxide anion, SOD, THC, clotting time and oxyhemocyanin were determined in MrNV and XSV-injected prawns and significant differences in some of the immunological parameters were found in the early days p.i. and became insignificant in the later days p.i.  相似文献   
8.
A soil bacterium capable of utilizing methyl parathion as sole carbon and energy source was isolated by selective enrichment on minimal medium containing methyl parathion. The strain was identified as belonging to the genus Serratia based on a phylogram constructed using the complete sequence of the 16S rRNA. Serratia sp. strain DS001 utilized methyl parathion, p-nitrophenol, 4-nitrocatechol, and 1,2,4-benzenetriol as sole carbon and energy sources but could not grow using hydroquinone as a source of carbon. p-Nitrophenol and dimethylthiophosphoric acid were found to be the major degradation products of methyl parathion. Growth on p-nitrophenol led to release of stoichiometric amounts of nitrite and to the formation of 4-nitrocatechol and benzenetriol. When these catabolic intermediates of p-nitrophenol were added to resting cells of Serratia sp. strain DS001 oxygen consumption was detected whereas no oxygen consumption was apparent when hydroquinone was added to the resting cells suggesting that it is not part of the p-nitrophenol degradation pathway. Key enzymes involved in degradation of methyl parathion and in conversion of p-nitrophenol to 4-nitrocatechol, namely parathion hydrolase and p-nitrophenol hydroxylase component “A” were detected in the proteomes of the methyl parathion and p-nitrophenol grown cultures, respectively. These studies report for the first time the existence of a p-nitrophenol hydroxylase component “A”, typically found in Gram-positive bacteria, in a Gram-negative strain of the genus Serratia. Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.  相似文献   
9.
In the present investigation, we have attempted to identify the potential two epiphytic yeast strains for growth promotion and management of chilli fruit rot. Seed treatment with Pichia guilliermondii showed increased seedling vigour index (55%), fresh weight (96%) and dry weight (45%) over untreated control. Furthermore, P. guilliermondii showed higher root colonisation ability, indole-3-acetic acid (IAA) production and phosphate solubilisation ability. On the other hand, seedling dip with Hanseniaspora uvarum induced higher levels of defence-related compounds in chilli seedlings challenge-inoculated with Colletotrichum capsici under glasshouse conditions. Among the different media tested, higher biomass of P. guilliermondii and H. uvarum was obtained in pine juice broth and sugarcane juice broth, respectively. Glycerol buffer formulation showed viability (>70%) of P. guilliermondii up to 4 months and H. uvarum up to 9 months when stored at ambient conditions. Seedling dip and foliar sprays with H. uvarum showed 37– 40% reduction in chilli fruit rot incidence under field conditions. It also showed higher (cumulative) accumulation of defence-related compounds in chilli leaves and ripe fruits under field conditions. The results of current investigation indicated a clear difference among the two epiphytic yeast strains. P. guilliermondii was identified as growth promoter of chilli and H. uvarum as antagonist of chilli fruit rot pathogen, C. capsici.  相似文献   
10.
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