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11.
Declining fertility rates in both human and animals is a cause for concern. While many of the infertility cases are due to known causes, idiopathic infertility is reported in 30% of the infertile couples. In such cases, 18% of the infertile males carry antisperm antibodies (ASAs). Such data are lacking in livestock, wherein 20–30% of the animals are being culled due to low fertility. In males, the blood–testis barrier (BTB) and biomolecules in the semen provide an immuno‐tolerant microenvironment for spermatozoa as they traverse the immunologic milieu of both the male and female reproductive tracts. For example, insults from environmental contaminants, infections and inflammatory conditions are likely to impact the immune privilege state of the testis and fertility. The female mucosal immune system can recognize allogenic spermatozoa‐specific proteins affecting sperm kinematics and sperm‐zona binding leading to immune infertility. Elucidating the functions and pathways of the immune regulatory molecules associated with fertilization are prerequisites for understanding their impact on fertility. An insight into biomolecules associated with spermatozoal immune tolerance may generate inputs to develop diagnostic tools and modulate fertility. High‐throughput sequencing technologies coupled with bioinformatics analyses provides a path forward to define the array of molecules influencing pregnancy outcome. This review discusses the seminal immune regulatory molecules from their origin in the testis until they traverse the uterine environment enabling fertilization and embryonic development. Well‐designed experiments and the identification of biomarkers may provide a pathway to understand the finer details of reproductive immunology that will afford personalized therapies.  相似文献   
12.
Oleuropein is one of the most abundant phenolic compounds found in olives. Epidemiological studies have indicated that an increasing intake of olive oil can significantly reduce the risk of breast cancer. However, the potential effect(s) of oleuropein on estrogen receptor (ER)-negative breast cancer is not fully understood. This study aims to understand the anticancer effects and underlying mechanism(s) of oleuropein on ER-negative breast cancer cells in vitro. The effect of oleuropein on the viability of breast cancer cell lines was examined by mitochondrial dye-uptake assay, apoptosis by flow cytometric analysis, nuclear factor-κB (NF-κB) activation by DNA binding/reporter assays and protein expression by Western blot analysis. In the present report, thiazolyl blue tetrazolium bromide assay results indicated that oleuropein inhibited the viability of breast cancer cells, and its effects were more pronounced on MDA-MB-231 as compared with MCF-7 cells. It was further found that oleuropein increased the level of reactive oxygen species and also significantly inhibited cellular migration and invasion. In addition, the activation of NF-κB was abrogated as demonstrated by Western blot analysis, NF-κB-DNA binding, and luciferase assays. Overall, the data indicates that oleuropein can induce substantial apoptosis via modulating NF-κB activation cascade in breast cancer cells.  相似文献   
13.
The leader RNA sequence of human immunodeficiency virus type 1 (HIV-1) consists of a complex series of stem loop structures that are critical for viral replication. Three-dimensional structural analysis by NMR of one of these structures, the SL1 stem loop of the packaging signal region, revealed a highly conserved purine rich loop with a structure nearly identical to the Rev-binding loop of the Rev response element. Using band-shift assays, surface plasmon resonance, and further NMR analysis, we demonstrate that this loop binds Rev. HIV-1 appears to have a second Rev-binding site close to the major splice donor site that may have an additional role in the viral life cycle.  相似文献   
14.
Acinetobacter calcoaceticus MTC 127 was able to grow on catechin and protocatechuic acid (PCA) as sole carbon source. Cells induced with catechin oxidized catechin and PCA at rates higher than cells of uninduced cultures. Two aromatic compounds, PCA and phloroglucinol carboxylic acid (PGCA) were isolated from culture filtrate of cells grown in catechin and characterized by infrared spectrometry and high performance thin-layer chromatography. Moreover, A. calcoaceticus MTC 127 produced high levels of PCA compared to PGCA in the degradation of catechin. Based upon these results, a pathway for the degradation of (+)-catechin in A. calcoaceticus MTC 127 is proposed. Enzymes extracted from catechin-induced culture showed catechin oxygenase (cox) and protocatechuate 3,4-dioxygenase (pcd) activities. Catechin oxygenase was purified by column chromatography and SDS-PAGE analysis showed a single band with an apparent molecular weight of 47 kDa.  相似文献   
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In vivo intracellular responses to auditory stimuli revealed that, in a particular population of cells of the ventral nucleus of the lateral lemniscus (VNLL) of rats, fast inhibition occurred before the first action potential. These experimental data were used to constrain a leaky integrate-and-fire (LIF) model of the neurons in this circuit. The post-synaptic potentials of the VNLL cell population were characterized using a method of triggered averaging. Analysis suggested that these inhibited VNLL cells produce action potentials in response to a particular magnitude of the rate of change of their membrane potential. The LIF model was modified to incorporate the VNLL cells’ distinctive action potential production mechanism. The model was used to explore the response of the population of VNLL cells to simple speech-like sounds. These sounds consisted of a simple tone modulated by a saw tooth with exponential decays, similar to glottal pulses that are the repeated impulses seen in vocalizations. It was found that the harmonic component of the sound was enhanced in the VNLL cell population when compared to a population of auditory nerve fibers. This was because the broadband onset noise, also termed spectral splatter, was suppressed by the fast onset inhibition. This mechanism has the potential to greatly improve the clarity of the representation of the harmonic content of certain kinds of natural sounds.  相似文献   
17.
Industrially important tannase producing fungi were isolated from tannery effluent using simple agar plate method. The isolates were screened by submerged fermentation using auto-controlled bioreactor. The colony diameter on the solid surface media shows high correlation with quantitative production of tannase. The isolate Aspergillus niger shows maximum production of both extracellular and intracellular enzyme.  相似文献   
18.
The decomposition of plant litter is one of the most important ecosystem processes in the biosphere and is particularly sensitive to climate warming. Aquatic ecosystems are well suited to studying warming effects on decomposition because the otherwise confounding influence of moisture is constant. By using a latitudinal temperature gradient in an unprecedented global experiment in streams, we found that climate warming will likely hasten microbial litter decomposition and produce an equivalent decline in detritivore-mediated decomposition rates. As a result, overall decomposition rates should remain unchanged. Nevertheless, the process would be profoundly altered, because the shift in importance from detritivores to microbes in warm climates would likely increase CO(2) production and decrease the generation and sequestration of recalcitrant organic particles. In view of recent estimates showing that inland waters are a significant component of the global carbon cycle, this implies consequences for global biogeochemistry and a possible positive climate feedback.  相似文献   
19.
Global gene expression profiling and cluster analysis in Xenopus laevis   总被引:4,自引:0,他引:4  
We have undertaken a large-scale microarray gene expression analysis using cDNAs corresponding to 21,000 Xenopus laevis ESTs. mRNAs from 37 samples, including embryos and adult organs, were profiled. Cluster analysis of embryos of different stages was carried out and revealed expected affinities between gastrulae and neurulae, as well as between advanced neurulae and tadpoles, while egg and feeding larvae were clearly separated. Cluster analysis of adult organs showed some unexpected tissue-relatedness, e.g. kidney is more related to endodermal than to mesodermal tissues and the brain is separated from other neuroectodermal derivatives. Cluster analysis of genes revealed major phases of co-ordinate gene expression between egg and adult stages. During the maternal-early embryonic phase, genes maintaining a rapidly dividing cell state are predominantly expressed (cell cycle regulators, chromatin proteins). Genes involved in protein biosynthesis are progressively induced from mid-embryogenesis onwards. The larval-adult phase is characterised by expression of genes involved in metabolism and terminal differentiation. Thirteen potential synexpression groups were identified, which encompass components of diverse molecular processes or supra-molecular structures, including chromatin, RNA processing and nucleolar function, cell cycle, respiratory chain/Krebs cycle, protein biosynthesis, endoplasmic reticulum, vesicle transport, synaptic vesicle, microtubule, intermediate filament, epithelial proteins and collagen. Data filtering identified genes with potential stage-, region- and organ-specific expression. The dataset was assembled in the iChip microarray database, , which allows user-defined queries. The study provides insights into the higher order of vertebrate gene expression, identifies synexpression groups and marker genes, and makes predictions for the biological role of numerous uncharacterized genes.  相似文献   
20.
Studies on the lipid peroxidation and antioxidant changes and their significance during myocardial injury have provided a new insight into the pathogenesis of heart disease. The heart failure subsequent to myocardial infarction may be associated with an antioxidant deficit as well as increased myocardial oxidative stress. The present study was designed to evaluate the effect of the combination of ferulic acid and ascorbic acid on antioxidant defense system and lipid peroxidation against isoproterenol (ISO)-induced myocardial infarction in rats. Induction of rats with isoproterenol (150 mg/kg body weight daily, i.p.) for 2 days resulted in a marked elevation in lipid peroxidation, serum marker enzymes (LDH, CPK, GOT, and GPT), and a significant decrease in activities of endogenous antioxidants (SOD, GPx, GST, CAT, and GSH). Pre-co-treatment with the combination of ferulic acid (20 mg/kg body weight/day) and ascorbic acid (80 mg/kg body weight/day) orally for 6 days, significantly attenuated these changes when compared to the individual treatment groups. Histopathological observations were also in correlation with the biochemical parameters. Thus, ferulic acid and ascorbic acid significantly counteracted the pronounced oxidative stress effect of ISO by the inhibition of lipid peroxidation, restoration of antioxidant status, and myocardial marker enzymes levels. In conclusion, these findings indicate the synergistic protective effect of ferulic acid and ascorbic acid on lipid peroxidation and antioxidant defense system during ISO-induced myocardial infarction and associated oxidative stress in rats.  相似文献   
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