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241.
Economic Botany - Swiddeners in the Bago Mountains, Myanmar collect two economically important non-timber forest products (NTFPs)—Rauvolfia serpentina (L.) Benth. ex Kurz (Apocynaceae) roots...  相似文献   
242.
Kenealy BP  Keen KL  Terasawa E 《Steroids》2011,76(9):861-866
Estrogens play a pivotal role in the control of female reproductive function. Recent studies using primate GnRH neurons derived from embryonic nasal placode indicate that 17β-estradiol (E2) causes a rapid stimulatory action. E2 (1 nM) stimulates firing activity and intracellular calcium ([Ca2+]i) oscillations of primate GnRH neurons within a few min. E2 also stimulates GnRH release within 10 min. However, the classical estrogen receptors, ERα and ERβ, do not appear to play a role in E2-induced [Ca2+]i oscillations or GnRH release, as the estrogen receptor antagonist, ICI 182,780, failed to block these responses. Rather, this rapid E2 action is, at least in part, mediated by a G-protein coupled receptor GPR30. In the present study we further investigate the role of ERα and ERβ in the rapid action of E2 by knocking down cellular ERα and ERβ by transfection of GnRH neurons with specific siRNA for rhesus monkey ERα and ERβ. Results indicate that cellular knockdown of ERα and ERβ failed to block the E2-induced changes in [Ca2+]i oscillations. It is concluded that neither ERα nor ERβ is required for the rapid action of E2 in primate GnRH neurons.  相似文献   
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The general pharmacological properties of TJ-19 extracts were orally investigated in various experimental animals. TJ-19 extracts showed no effect on general behavior and on central nervous system such as spontaneous locomotor activity, proconvulsant and anti-convulsant responses, analgesic activity, body temperature and hexobarbital sleeping time at all doses of 0.5, 1 and 2 g/kg in mice. Further, TJ-19 extracts showed no effect on contractile responses of isolated guinea pig ileum induced by acetylcholine, histamine and BaCl2 at concentrations of 10(-6), 10(-5), and 10(-4) g/ml. TJ-19 extracts, however, increased the respiratory rate, heart rate, blood pressure, systolic pressure, diastolic pressure, and decreased the blood flow in dogs at all doses of 0.5, 1 and 2 g/kg via duodenal administration. Further, TJ-19 extracts decreased the interval of PR and QT of EKG parameters in dogs at doses of 1 and 2 g/kg. TJ-19 extracts increased the intestinal transport of charcoal meal in rats at doses of 1 and 2 g/kg. TJ-19 increased the urinary Na+ excretion at all doses of 0.5, 1, and 2 g/kg, and increased the urinary K+ and Cl- excretion at 1 and 2 g/kg, although it showed no effect on urine volume output in rats. These data suggest that TJ-19 stimulates the sympathetic nervous system function at a pharmacological dose of under 0.5 g/kg, and has possibility to increase the intestinal peristalsis and urinary electrolyte excretion at higher doses.  相似文献   
247.
Summary The tyrosine phenol lyase (TPL) gene was cloned from the genomic DNA of aEscherichia intermedia strain and the nucleotide sequence of the TPL structural gene was determined. The 1801 bpHincll-Nrul DNA fragment containing the TPL gene had an open reading frame of 1368 bp and the deduced amino acid sequence was 456 residues long with a molecular weight of 51,441 daltons.  相似文献   
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The structural and enzymatic characteristics of a cutinase‐like enzyme (CLE) from Cryptococcus sp. strain S‐2, which exhibits remote homology to a lipolytic enzyme and a cutinase from the fungus Fusarium solani (FS cutinase), were compared to investigate the unique substrate specificity of CLE. The crystal structure of CLE was solved to a 1.05 Å resolution. Moreover, hydrolysis assays demonstrated the broad specificity of CLE for short and long‐chain substrates, as well as the preferred specificity of FS cutinase for short‐chain substrates. In addition, site‐directed mutagenesis was performed to increase the hydrolysis activity on long‐chain substrates, indicating that the hydrophobic aromatic residues are important for the specificity to the long‐chain substrate. These results indicate that hydrophobic residues, especially the aromatic ones exposed to solvent, are important for retaining lipase activity. Proteins 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
249.

Background  

Porphyromonas gingivalis, a periodontal pathogen, expresses a number of virulence factors, including long (FimA) and short (Mfa) fimbriae as well as gingipains comprised of arginine-specific (Rgp) and lysine-specific (Kgp) cysteine proteinases. The aim of this study was to examine the roles of these components in homotypic biofilm development by P. gingivalis, as well as in accumulation of exopolysaccharide in biofilms.  相似文献   
250.
Kim W  Jessen HM  Auger AP  Terasawa E 《Peptides》2009,30(1):103-110
The G-protein coupled receptor, GPR54, and its ligand, kisspeptin-54 (a KiSS-1 derived peptide) have been reported to be important players in control of LHRH-1 release. However, the role of the GPR54 signaling in primate reproductive senescence is still unclear. In the present study we investigated whether KiSS-1, GPR54, and LHRH-1 mRNA in the brain change after menopause in female rhesus monkeys using quantitative real-time PCR. Results indicate that KiSS-1, GPR54, and LHRH-1 mRNA levels in the medial basal hypothalamus (MBH) in postmenopausal females (28.3+/-1.1 years of age, n=5) were all significantly higher than that in eugonadal adult females (14.7+/-2.1 years of age, n=9), whereas KiSS-1, GPR54, and LHRH-1 mRNA levels in the preoptic area (POA) did not have any significant changes between the two age groups. To further determine the potential contribution by the absence of ovarian steroids, we compared the changes in KiSS-1, GPR54, and LHRH-1 mRNA levels in young adult ovarian intact vs. young ovariectomized females. Results indicate that KiSS-1 and LHRH-1 mRNA levels in the MBH, not POA, in ovariectomized females were significantly higher than those in ovarian intact females, whereas GPR54 mRNA levels in ovariectomized females had a tendency to be elevated in the MBH, although the values were not quite statistically significant. Collectively, in the primate the reduction in the negative feedback control by ovarian steroids appears to be responsible for the aging changes in kisspeptin-GPR54 signaling and the elevated state of the LHRH-1 neuronal system.  相似文献   
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