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81.
A radioimmunoassay (RIA) has been developed for the determination of alpha-human atrial natriuretic polypeptide (alpha-hANP) in human plasma. Antibodies generated in rabbits recognized alpha-hANP-related peptides containing the subsequence flanked by two cysteine residues at position 7 and 23 equally. Radiolabelled tracer prepared by iodination with chloramine-T method was purified by high performance liquid chromatography. Immunoreactive (ir-) alpha-hANP was extracted from human plasma by Sep-Pak C18 column. The plasma ir-alpha-hANP concentrations in normal, healthy adults were 178 +/- 16 pg/ml in male and 182 +/- 18 pg/ml in female, respectively. Plasma ir-alpha-hANP increased significantly after acute intravenous administration of isotonic saline. Plasma levels were elevated in patients with various disease states accompanying increased body fluid volume, whereas those in patients with idiopathic edema were decreased despite excessive salt and water retention. These results suggest that alpha-hANP plays an important role in the regulation of body fluids and may have primary or secondary pathophysiological significance in various disease states.  相似文献   
82.
A patient with a rare combination of prolactinoma and aldosterone producing adrenal adenoma (APA) was reported in relation to studies concerning dopaminergic regulation of PRL and aldosterone secretion. The patient is a 38-year-old female with plasma PRL and aldosterone concentrations (PAC) of 563 ng/ml and 54 ng/dl, respectively. A bolus of 10 mg of metoclopramide significantly increased plasma PRL in 6 normal subjects and in 4 patients with APA, whereas the responses were blunted in 7 patients with prolactinoma and in our patient. The response of aldosterone to metoclopramide was less than that of PRL, but similar in all studied subjects, indicating that the dopaminergic inhibition of aldosterone secretion is less than that of PRL in normal subjects and did not change in patients with APA or prolactinoma. Oral administration of 2.5 mg of bromocriptine suppressed plasma PRL significantly in all the subjects studied, but did not produce any consistent changes in PAC. Discrepancies in the response of PRL and aldosterone to metoclopramide and to bromocriptine suggest a difference in the dopaminergic regulation of PRL and aldosterone secretion in both normal subjects and patients with prolactinoma and APA. It is unlikely that reduced dopaminergic inhibition is the basis for hypersecretion of PRL and aldosterone in our patient.  相似文献   
83.
Using a synthetic 21-residue endothelin as antigen, we have produced an antiserum for endothelin and developed a specific and sensitive radioimmunoassay (RIA) for endothelin. The minimum detection limit of the RIA was 1 pg/tube. Immunoreactive (ir-) endothelin was extracted from the culture medium by Bondelute C8 column. The ir-endothelin in the culture medium of endothelial cells (EC) from bovine pulmonary artery and carotid artery was 1.48 ng/ml and 3.31 ng/ml, respectively. Reverse-phase high performance liquid chromatography coupled with the RIA revealed that ir-endothelin in the culture medium comprised one major component corresponding to synthetic endothelin. In addition, the cultured EC of bovine pulmonary artery were specifically stained by immunohistochemical technique. These results suggest that endothelin could be produced in the EC of the pulmonary and carotid arteries besides the aorta. The RIA presented in this study could be an useful tool to investigate the pathophysiologic significance of endothelin.  相似文献   
84.
85.
Journal of Plant Research - Histone modification is an important epigenetic mechanism in eukaryotes. Histone acetyltransferase and deacetylase regulate histone acetylation levels antagonistically,...  相似文献   
86.
Pleurocope iriomotensis sp. n. and Prethura tuberculata sp. n. are described from Iriomote Island, Ryukyu Archipelago, southern Japan. These are the first records of Pleurocope from the Pacific and of Prethura from the Asian Pacific coast. Pleurocope iriomotensis differs from its congeners in having lateral spine-like processes on pereonite 4 and coxal plates of pereonite 7. Prethura tuberculata can be distinguished from its single congener in having a lateral short projection of protopod of pleopod 2.  相似文献   
87.
Several studies of stem cell-based gene therapy have indicated that long-lasting regeneration following vessel ischemia may be stimulated through VEGFA gene therapy and/or MSC transplantation for reduction of ischemic injury in limb ischemia and heart failure. The therapeutic potential of MSC transplantation can be further improved by genetically modifying MSCs with genes which enhance angiogenesis following ischemic injury. In the present study, we aimed to develop an approach in MSC-based therapy for repair and mitigation of ischemic injury and regeneration of damaged tissues in ischemic disease. HSP70 promoter-driven VEGFA expression was induced by resveratrol (RSV) in MSCs, and in combination with known RSV biological functions, the protective effects of our approach were investigated by using ex vivo aortic ring coculture system and a 3D scaffolds in vivo model. Results of this investigation demonstrated that HSP promoter-driven VEGFA expression in MSC increased approximately 2-fold over the background VEGFA levels upon HSP70 promoter induction by RSV. Exposure of HUVEC cells to medium containing MSC in which VEGFA had been induced by cis-RSV enhanced tube formation in the treated HUVEC cells. RSV-treated MSC cells differentiated into endothelial-like phenotypes, exhibiting markedly elevated expression of endothelial cell markers. These MSCs also induced aortic ring sprouting, characteristic of neovascular formation from pre-existing vessels, and additionally promoted neovascularization at the MSC transplantation site in a mouse model. These observations support a hypothesis that VEGFA expression induced by cis-RSV acting on the HSP70 promoter in transplanted MSC augments the angiogenic effects of stem cell gene therapy. The use of an inducible system also vastly reduces possible clinical risks associated with constitutive VEGFA expression.  相似文献   
88.
A plausible explanation for many MHC-linked diseases is lacking. Sequencing of the MHC class I region (coding units or full contigs) in several human and nonhuman primate haplotypes allowed an analysis of single nucleotide variations (SNV) across this entire segment. This diversity was not evenly distributed. It was rather concentrated within two gene-rich clusters. These were each centered, but importantly not limited to, the antigen-presenting HLA-A and HLA-B/-C loci. Rapid evolution of MHC-I alleles, as evidenced by an unusually high number of haplotype-specific (hs) and hypervariable (hv) (which could not be traced to a single species or haplotype) SNVs within the classical MHC-I, seems to have not only hitchhiked alleles within nearby genes, but also hitchhiked deleterious mutations in these same unrelated loci. The overrepresentation of a fraction of these hvSNV (hv1SNV) along with hsSNV, as compared to those that appear to have been maintained throughout primate evolution (trans-species diversity; tsSNV; included within hv2SNV) tends to establish that the majority of the MHC polymorphism is de novo (species specific). This is most likely reminiscent of the fact that these hsSNV and hv1SNV have been selected in adaptation to the constantly evolving microbial antigenic repertoire.  相似文献   
89.
We isolated genes for hatching enzymes and their paralogs having two cysteine residues at their N-terminal regions in addition to four cysteines conserved in all the astacin family proteases. Genes for such six-cysteine-containing astacin proteases (C6AST) were searched out in the medaka genome database. Five genes for MC6AST1 to 5 were found in addition to embryo-specific hatching enzyme genes. RT-PCR and whole-mount in situ hybridization evidenced that MC6AST1 was expressed in embryos and epidermis of almost all adult tissues examined, while MC6AST2 and 3 were in mesenterium, intestine, and testis. MC6AST4 and 5 were specifically expressed in jaw. In addition, we cloned C6AST cDNA homologs from zebrafish, ayu, and fugu. The MC6AST1 to 5 genes were classified into three groups in the phylogenetic positions, and the expression patterns and hatching enzymes were clearly discriminated from other C6ASTs. Analysis of the exon–intron structures clarified that genes for hatching enzymes MHCE and MAHCE were intron-less, while other MC6AST genes were basically the same as the gene for another hatching enzyme MLCE. In the basal Teleost, the C6AST genes having the ancestral exon–intron structure (nine exon/eight intron structure) first appeared by duplication and chromosomal translocation. Thereafter, maintaining such ancestral exon–intron structure, the LCE gene was newly diversified in Euteleostei, and the MC6AST1 to 5 gene orthologs were duplicated and diversified independently in respective fish lineages. The HCE gene lost all introns in Euteleostei, whereas in the lineage to zebrafish, it was translocated from chromosome to chromosome and lost some of its introns.Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.The nucleotide sequence data reported in the present paper will appear in the DDBJ/EMBL/GenBank nucleotide sequence databases with accession numbers from AB256940 to AB256952.  相似文献   
90.
Coronary artery disease (CAD) is based on the atherosclerosis of coronary artery and may manifest with myocardial infarction or angina pectoris. Although it is widely accepted that genetic factors are linked to CAD and several disease-related genes have been reported, only a few could be replicated suggesting that there might be some other CAD-related genes. To identify novel susceptibility loci for CAD, we used microsatellite markers in the screening and found six different candidate CAD loci. Subsequent single nucleotide polymorphism (SNP) association studies revealed an association between CAD and megakaryoblastic leukemia factor-1 gene (MKL1). The association with a promoter SNP of MKL1, ?184C > T, was found in a Japanese population and the association was replicated in another Japanese population and a Korean population. Functional analysis of the MKL1 promoter SNP suggested that the higher MKL1 expression was associated with CAD. These findings suggest that MKL1 is involved in the pathogenesis of CAD.  相似文献   
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