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881.
Intramuscular long-chain fatty acids (LCFAs) play an important role in energy production and initiation of mitochondrial oxidation of lipids. Herein, we report a natural porcine placenta steroid extract (PPSE) that stimulates transdifferentiation and lipid accumulation in bovine myogenic satellite cells (MSCs). The steroids hormones in PPSE were analyzed using enzyme-linked immunosorbant assay and presence of LCFA was established using gas chromatography. At 70% confluent growth, cells were treated with PPSE, LCFAs, transdifferentiation cocktail and commercially available steroid hormones. The working concentrations of all chemicals were manipulated similar to PPSE. The cells were observed for morphological changes and subjected to quantitative analysis of lipid deposition on Days 2, 4, and 6 of treatment. PPSE-treated MSCs exclusively transformed into lipid-accumulated adipose-like cells (ALCs). However, myotubes or adipocytes were formed in cells treated with other chemicals. Expression of different genes was studied to ascertain the molecular mechanism involved in ALC formation. CD36, fatty acid binding protein 4, and peroxisome proliferator-activated receptor-gamma were up-regulated. The expression of CD36 was established through immunocyto-chemical analysis. A viability assay was used to confirm the effect of PPSE on proliferation of MSCs. Hence, a natural steroid extract from porcine was found as a nontoxic mixture, which induces lipid accumulation and transdifferentiation of MSCs to ALCs. From the gene expression studies, it was established that the extract works almost in homogenous manner with other lipid inducers.  相似文献   
882.
Impairments in attentional behaviors, including over-selectivity, under-selectivity, distractibility and difficulty in shift of attention, are widely reported in several developmental disorders, including autism. Uncharacteristic inhibitory to excitatory neuronal number ratio (IER) and abnormal synaptic strength levels in the brain are two broadly accepted neurobiological disorders observed in autistic individuals. These neurobiological findings are contrasting and their relation to the atypical attentional behaviors is not clear yet. In this paper, we take a computational approach to investigate the relation of imbalanced IER and abnormal synaptic strength to some well-documented spectrum of attentional impairments. The computational model is based on a modified version of a biologically plausible neural model of two competing minicolumns in IT cortex augmented with a simple model of top-down attention. Top-down attention is assumed to amplify (attenuates) attended (unattended) stimulus. The inhibitory synaptic strength parameter in the model is set such that typical attentional behavior is emerged. Then, according to related findings, the parameter is changed and the model's attentional behavior is considered. The simulation results show that, without any change in top-down attention, the abnormal inhibitory synaptic strength values - and IER imbalance- result in over-selectivity, under-selectivity, distractibility and difficulty in shift of attention in the model. It suggests that the modeled neurobiological abnormalities can be accounted for the attentional deficits. In addition, the atypical attentional behaviors do not necessarily point to impairments in top-down attention. Our simulations suggest that limited changes in the inhibitory synaptic strength and variations in top-down attention signal affect the model's attentional behaviors in the same way. So, limited deficits in the inhibitory strength may be alleviated by appropriate change in top-down attention biasing. Nevertheless, our model proposes that this compensation is not possible for very high and very low values of the inhibitory strength.  相似文献   
883.
A biocontrol Streptomyces isolate (C) was tested for its plant growth promoting qualities under saline conditions. Exposure to elevated osmotic strengths up to 300 mM NaCl increased dry weight and cfu/ml significantly. The isolate C produced indolyl-3-acetic acid (IAA) into the medium in the amount of 2.4 μg/ml. The amount of auxin increased after adding salt and reached to 4.7 μg/ml in 300 mM NaCl. Biosynthesis of siderophore was detectable and increased in presence of NaCl. Streptomyces isolate C showed good solubilization of tricalcium phosphate in culture medium with 92 mg/l. Solubilization decreased in presence of NaCl. Soil treatment with isolate C increased the growth and development of wheat plant in normal and saline conditions. In this treatment there were significant increases in germination rate, percentage and uniformity, shoot length and dry weight compared to the control. Applying the bacterial inocula increased the concentration of N, P, Fe and Mn in wheat shoots grown in normal and saline soil, but had non-significant effect on other micro and macronutrients concentrations. Results of this study show that Streptomyces isolate C has potential to be utilized as biofertilizer in saline soils.  相似文献   
884.
Heightened dopaminergic activity has been shown to be implicated in some major neuropsychiatric disorders such as schizophrenia. Use of dopaminergic antagonists was limited by some serious side effects related to unspecific blocking of dopamine receptors. Thus a target specific dopamine receptor gene silencing method such as using small interfering RNA (siRNA) might be useful. In this study recombinant plasmids expressing siRNA against dopamine receptors (D1-D5DRs) were produced, and their efficiency in knocking down of receptors in were assessed in rat neuroblastoma cell line (B65), using Real-time PCR method. Furthermore, D2DR siRNA expressing plasmid was injected into the rat nucleus accumbens bilaterally to investigate whether it can prevent the hyperactivity induced by apomorphine. Locomotion was measured in 10 min intervals, 50 min before and 60 min after apomorphine injection (0.5 mg/kg, S.C). Our results indicated that the mRNA level of dopamine receptors were reduced between 25 and 75% in B65 cells treated with the plasmids in vitro. In behavioral tests, locomotion was lower at least in the second 10 min after apomorphine injection in rats treated with plasmid expressing D2DR siRNA compare to control group [F (4,24) = 2.77, (P < 0.05)]. The spontaneous activity of treated rats was normal. In conclusion, dopamine receptors can be downregulated by use of siRNA expressing plasmids in nucleus accumbens. Although our work may have some possible clinical applications; the potentially therapeutic application of siRNA in knocking down of dopamine receptors needs further studies.  相似文献   
885.
886.
S Ramadhani  SR Mousavi  M Talebi 《Gene》2012,498(2):177-182
We cloned a gene, kexD, that provides a multidrug-resistant phenotype from multidrug-resistant Klebsiella pneumoniae MGH78578. The deduced amino acid sequence of KexD is similar to that of the inner membrane protein, RND-type multidrug efflux pump. Introduction of the kexD gene into Escherichia coli KAM32 resulted in a MIC that was higher for erythromycin, novobiocin, rhodamine 6G, tetraphenylphosphonium chloride, and ethidium bromide than that of the control. Intracellular ethidium bromide levels in E. coli cells carrying the kexD gene were lower than that in the control cells under energized conditions, suggesting that KexD is a component of an energy-dependent efflux pump. RND-type pumps typically consist of three components: an inner membrane protein, a periplasmic protein, and an outer membrane protein. We discovered that KexD functions with a periplasmic protein, AcrA, from E. coli and K. pneumoniae, but not with the periplasmic proteins KexA and KexG from K. pneumoniae. KexD was able to utilize either TolC of E. coli or KocC of K. pneumoniae as an outer membrane component. kexD mRNA was not detected in K. pneumoniae MGH78578 or ATCC10031. We isolated erythromycin-resistant mutants from K. pneumoniae ATCC10031, and some showed a multidrug-resistant phenotype similar to the drug resistance pattern of KexD. Two strains of multidrug-resistant mutants were investigated for kexD expression; kexD mRNA levels were increased in these strains. We conclude that changing kexD expression can contribute to the occurrence of multidrug-resistant K. pneumoniae.  相似文献   
887.
The purpose of this study was to investigate the effect of clomiphene citrate and human chorionic gonadotropin (HCG) on the structural changes, as well as the evaluation of the expression of cation channel sperm‐associated protein 1 (CatSper1), cation channel sperm‐associated protein 2 (CatSper2), luteinizing hormone/choriogonadotropin receptor (LHCGR), and steroidogenic factor 1 (SF1) genes in testicular tissue of rats. All rats divided into five groups as follows; G1 as the control group that received normal saline, G2 received olive oil, G3 received 100 IU/kg HCG, G4 received 5 mg/kg clomiphene citrate, and G5 received 5 mg/kg clomiphene citrate and 100 IU/kg HCG. At the end of the experiment period, Day 56, blood samples were taken and the serum was isolated. Then, histomorphometric analysis, hormonal assess, and real‐time polymerase chain reaction to measure the expression of CatSper1, CatSper2, LHCGR, and SF1 genes were performed. The results showed that the concentrations of testosterone, follicle‐stimulating hormone, and luteinizing hormone were decreased in the G4 group, whereas these parameters were increased in the G3 group. A comparison of the sperm quality indicated a significant reduction in the quality of sperm cells in the G4 group compared with other groups. The quality of sperm was significantly enhanced in the G3 and G5 groups in comparison with the G1 group. Also, our findings demonstrated that the expression of CatSper1, CatSper2, LHCGR, and SF1 genes were significantly elevated in the G3 group when compared with other experimental groups. According to the obtained results, it seems that clomiphene citrate reduces the process of spermatogenesis and the detrimental impacts of this compound would be neutralized by the administration of HCG.  相似文献   
888.
Abstract

Plants can be used naturally to mitigate environmental pollution, such as air pollution; however, it is important to evaluate plant susceptibility to air pollution when considering green space creation in urban areas. In this study, we investigated the biochemical and physiological parameters, including pH, and ascorbic acid, relative water, total chlorophyl, proline, soluble sugar, protein, and free amino acid contents of two gymnosperm tree species, Cupressus arizonica Greene and Juniperus excelsa Bieb. Using these data, we computed the Air Pollution Tolerance Index (APTI) and Anticipated Performance Index (API) of the trees at five sites in Isfahan, Iran, to determine their applicability for greenbelt establishment. Our results indicated that these evergreen species are good indicators of air pollution and can be used as an early warning tool for air pollution level that is harmful to human health.  相似文献   
889.
Exposure to extremely low-frequency electromagnetic fields (ELF-EMF) is inevitable in some industries. There are concerns about the possible effects of this exposure. The present study aimed to investigate the effect of chronic exposure to extremely low-frequency electromagnetic fields on sleep quality, stress, depression and anxiety among power plant workers.

In this cross-sectional study, 132 power plant workers were included as the exposed group and 143 other workers were included as the unexposed group. The intensity of ELF-EMF at work stations was measured by using the IEEE Std C95.3.1 standard and then the time weighted average was calculated. Sleep quality, stress, depression and anxiety were measured by using the Pittsburgh Sleep Quality Index Questionnaire; and the Depression, Anxiety and Stress Scale.

The workers in the exposed group experienced significantly poorer sleep quality than the unexposed group. Depression was also more severe in the exposed group than the unexposed group (P = 0.039). Increased exposure to ELF-EMF had a direct and significant relation with increased stress, depression, and anxiety. Sleep quality in technicians with the highest exposure was significantly lower than the other groups.

This study suggests that long-term occupational exposure to ELF-EMF may lead to depression, stress, anxiety and poor sleep quality.  相似文献   

890.
Bioprocess and Biosystems Engineering - Simpler and biocompatible greener approaches for the assembly of nanoparticles (NPs) have been the focus lately which have minimum environmental damage and...  相似文献   
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