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It has been established that secretion of gonadotropin (GtH) and growth hormone (GH) release in goldfish are both stimulated
by GtH-releasing hormone (GnRH); in addition GtH secretion is inhibited by dopamine D2 mechanisms. In the present study, depletion of protein kinase C (PKC) in goldfish pituitary cells reduced the GtH and GH
responses to GnRH and an activator of PKC in static culture. In perifusion studies, GtH released in response to sGnRH analog
was greatly attenuated in PKC-depleted cells, however, hormone responses to forskolin were enhanced. Stimulation of dopamine
D2 receptors reduced the GtH, but not the GH, responses elicited by PKC activators. These results indicate that PKC participates
in the GtH and GH responses to natural neuroendocrine regulators in the goldfish.
Résumé Il a été établi que chez le poisson rouge, les sécrétions de gonadotropine (GtH) et d'hormone de croissance (GH) sont toutes les deux stimulées par la gonadolibérine (GnRH); de plus, la sécrétion de GtH est inhibée par des mécanismes dopaminergiques de type D2. Dans le présent travail, la déplétion de la teneur en protéine kinase C (PKC) dans des cellules hypophysaires de poisson rouge réduit les résponses en GtH et GH au GnRH et à un activateur de la PKC de cellules maintenues en incubation statique. Dans des cellules maintenues en périfusion et soumises à une déplétion en PKC, la GtH libérée en réponse à un analogue du sGnRH est fortement diminuée, cependent les réponses hormonales à la forskoline sont augmentées. La stimulation des récepteurs dopaminergiques D2 réduit, dans le cas d'action d'activateur de la PKC, la réponse en GtH mais pas en GH. Ces résultats indiquent que la PKC est impliquée dans les mécanismes de régulation de GtH et GH par des facteurs neuroendocriniens naturels.相似文献
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Abi-Rached L Jobin MJ Kulkarni S McWhinnie A Dalva K Gragert L Babrzadeh F Gharizadeh B Luo M Plummer FA Kimani J Carrington M Middleton D Rajalingam R Beksac M Marsh SG Maiers M Guethlein LA Tavoularis S Little AM Green RE Norman PJ Parham P 《Science (New York, N.Y.)》2011,334(6052):89-94
Whole genome comparisons identified introgression from archaic to modern humans. Our analysis of highly polymorphic human leukocyte antigen (HLA) class I, vital immune system components subject to strong balancing selection, shows how modern humans acquired the HLA-B*73 allele in west Asia through admixture with archaic humans called Denisovans, a likely sister group to the Neandertals. Virtual genotyping of Denisovan and Neandertal genomes identified archaic HLA haplotypes carrying functionally distinctive alleles that have introgressed into modern Eurasian and Oceanian populations. These alleles, of which several encode unique or strong ligands for natural killer cell receptors, now represent more than half the HLA alleles of modern Eurasians and also appear to have been later introduced into Africans. Thus, adaptive introgression of archaic alleles has significantly shaped modern human immune systems. 相似文献
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We have evaluated the acetylcholine esterase and malate dehydrogenase activity in the muscle, epinephrine, norepinephrine, insulin and T3 content in the serum of epileptic rats. Acetylcholine esterase and malate dehydrogenase activity increased in the muscle and decreased in the heart of the epileptic rats compared to control. Insulin and T3 content were increased significantly in the serum of the epileptic rats. Our results suggest that repetitive seizures resulted in increased metabolism and excitability in epileptic rats. Bacopa monnieri and Bacoside-A treatment prevents the occurrence of seizures there by reducing the impairment on peripheral nervous system. 相似文献
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John P. Chang Richard M. Jobin Anderson O. L. Wong 《Fish physiology and biochemistry》1993,11(1-6):25-33
Evidence for the involvement of Ca2+, protein kinase C, cAMP, and arachidonic acid metabolism in mediating gonadotropin (GTH) and growth hormone (GH) release
in the goldfish is reviewed. Models for the signal transduction pathways mediating GTH-releasing hormone (GnRH) and dopamine
actions on GTH and GH secretion are postulated. A novel hypothesis that two GnRHs which bind to the same receptor type activate
different transduction cascade in two different cell types (GTH vs. GH) as well as within the same cell type (GTH) is presented.
Résumé Cette revue présente les données expérimentales démontrant l'implication de Ca++, de la protéine kinase C et du métabolismes de l'acide arachidonique dans les mécanismes régulant la sécrétion des hormones gonadotrope (GTH) et de croissance (GH). Des modèles de signaux de transduction de l'action de la gonadolibérine (GnRH) et de la dopamine sur la sécrétion de GTH et de GH sont proposés. Les deux GnRHs existant chez le poisson rouge pourraient se lier au même type de récepteur et activer différentes voies de transduction dans deux différents types cellulaires (GTH vs. GH) ou dans un seul type (GTH).相似文献
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Jobin Jose Kattoor Sharad Saurabh Shubhankar Sircar Kuldeep Dhama Souvik Ghosh 《The Veterinary quarterly》2017,37(1):252-261
Background: Rotavirus C (RVC), a known etiological agent of diarrheal outbreaks, mainly inflicts swine population globally with sporadic incidence in human, cattle, ferret, mink and dog.
Objective: To demonstrate the presence of RVC in Indian swine population and characterization of its selected structural (VP6) and non-structural (NSP4 and NSP5) genes.
Methods: A total of 108 diarrheic samples from different regions of India were used. Isolated RNA was loaded onto polyacrylamide gel to screen for the presence of RVs through the identification of specific electrophoretic genomic migration pattern. To characterize the RVC strains, VP6 gene and NSP4 and NSP5 genes were amplified, sequenced and analyzed.
Results: Based on VP6 gene specific diagnostic RT-PCR, the presence of RVC was confirmed in 12.0% (13/108) piglet fecal specimens. The nucleotide sequence analysis of VP6 gene, encoding inner capsid protein, from selected porcine RVC (PoRVC) strains revealed more than 93% homologies to human RVC strains (HuRVC) of Eurasian origin. These strains were distant from hitherto reported PoRVCs and clustered with HuRVCs, owning I2 genotype. However, the two non-structural genes, i.e. NSP4 and NSP5, of these strains were found to be of swine type, signifying a re-assortment event that has occurred in the Indian swine population.
Conclusion: The findings indicate the presence of human-like RVC in Indian pigs and division of RVC clade with I2 genotype into further sub-clades. To the best of our knowledge, this appears to be the first report of RVC in Indian swine population. Incidence of human-like RVC VP6 gene in swine supports its subsequent zoonotic prospective. 相似文献
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Jobin Benoît Beaulieu Jason Grenier Marcelle Bélanger Luc Maisonneuve Charles Bordage Daniel Filion Bernard 《Landscape Ecology》2003,18(6):575-590
Most landscape definitions in the western world are based on soil, climatic, or physiographic features and do not integrate
humans as an integral part of the landscape. We present an approach where landscape types have been delineated in southern
Québec, Canada based on current land use where anthropogenic and agricultural activities are concentrated as a practical application
of the holistic approach in landscape definition. Landsat-TM satellite images were classified and the 27 habitat classes were
regrouped into 5 general land cover classes (cash crop, dairy farming, forest, anthropogenic, wetlands) and overlaid onto
soil landscape polygons to characterize natural boundary units. Cluster analyses were used to aggregate these polygons into
seven agricultural types of land scape forming a gradient from urban and high-intensity cash crop farming activities to landscapes
dominated by a mosaic of agriculture and forested areas. Multivariate analyses of raw data and of socio-economic and farming
practices variables were used to describe the defined types of landscape and these were projected over three established land
classification systems of southern Québec (Canadian ecoregions, North American Bird Conservation Initiative regions and Corn
Heat Unit regions) to compare their similarity in terms of land cover and for planning of future ecological studies. Because
agricultural landscapes are highly dynamic, they are bound to undergo changes in the near future. Our landscape delineation
may serve as an experimental setup where land scape dynamics and wildlife populations and community structures could be monitored.
Because the information we used to delineate and characterize agricultural landscape types is readily available in other countries,
our approach could easily be adapted to similar data sources under and a wide variety of landscape types.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Bacopa monnieri is an outstanding nervine tonic used for raising the mental performance. It helps in concentration, comprehension, recall and alertness, Brahmi is particularly beneficial as it aids in categorizing information in brain and its subsequent expression. Bacopa is also called as a natural antioxidant which may give details its neuroprotective role seen in the memory centers of the brain. Epilepsy is neuronal disorder characterized by learning, cognitive and memory impairments. The present review summarizes information concerning botany, chemistry and beneficial effect of Bacopa monnieri on epilepsy associated behavioral deficits. 相似文献
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Wallace BD Wang H Lane KT Scott JE Orans J Koo JS Venkatesh M Jobin C Yeh LA Mani S Redinbo MR 《Science (New York, N.Y.)》2010,330(6005):831-835
The dose-limiting side effect of the common colon cancer chemotherapeutic CPT-11 is severe diarrhea caused by symbiotic bacterial β-glucuronidases that reactivate the drug in the gut. We sought to target these enzymes without killing the commensal bacteria essential for human health. Potent bacterial β-glucuronidase inhibitors were identified by high-throughput screening and shown to have no effect on the orthologous mammalian enzyme. Crystal structures established that selectivity was based on a loop unique to bacterial β-glucuronidases. Inhibitors were highly effective against the enzyme target in living aerobic and anaerobic bacteria, but did not kill the bacteria or harm mammalian cells. Finally, oral administration of an inhibitor protected mice from CPT-11-induced toxicity. Thus, drugs may be designed to inhibit undesirable enzyme activities in essential microbial symbiotes to enhance chemotherapeutic efficacy. 相似文献
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