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Rhynchospio glutaea (Ehlers, 1897 Ehlers, E. 1897. Polychaeten. Ergebnisse der Hamburger Magalhaensischen Sammelreise 1892/93. L. Friederichsen & Co., Hamburg, Germany. [Google Scholar]), Rhynchospio arenincola Hartman, 1936 Hartman, O. 1936. New species of Spionidae (Annelida Polychaeta) from the coast of California. University of California Publications in Zoology 41, 4552. [Google Scholar] and Rhynchospio arenincola asiatica Chlebovitsch, 1959 Chlebovitsch, V.V. 1959. Species of Polychaeta worms from the Kurile Islands, which are new or recorded for the first time in the USSR fauna. Zoologichesky Zhurnal 38, 167181. [Google Scholar], originally described from Strait of Magellan, California, and South Kurile Islands respectively, appear similar to each other in adult morphology. These species and subspecies have been considered by some authors as subjective synonyms and are here referred to as members of the R. glutaea complex. Sequence data of four gene fragments (2465 bp in total) of the mitochondrial 16S rDNA, nuclear 18S and 28S rDNA, and Histone 3 have shown that R. glutaea complex individuals from the South West Atlantic (Argentina), North East Pacific (British Columbia and Oregon) and North West Pacific (South Korea) were genetically distant and not conspecific. These data also indicate that R. arenincola from North America and R. aff. asiatica from South Korea are more closely related to each other, and both are closer to R. glutaea from South America than to R. nhatrangi from Vietnam: nhatrangi (glutaea (arenincola-aff. asiatica)). Adults of the R. glutaea complex are hermaphrodites and the arrangement of gametes is suggested to be a crucial reproductive character for distinguishing these species. Based on this character, two species of the complex are apparent in the North West Pacific: R. asiatica Chlebovitsch, 1959 Chlebovitsch, V.V. 1959. Species of Polychaeta worms from the Kurile Islands, which are new or recorded for the first time in the USSR fauna. Zoologichesky Zhurnal 38, 167181. [Google Scholar] stat. nov. from the Kurile Islands (not analysed here) and an unnamed species from the mainland coast of Asia (here referred to as R. aff. asiatica). Adult morphology of R. asiatica stat. nov. is briefly described and illustrated. The lectotype and the type locality of the species on Iturup Is. are established for the first time. An identification key is provided to the 10 currently recognized Rhynchospio species.  相似文献   
3.
Sufficient supply of NADPH is one of the most important factors affecting the productivity of biotransformation processes. In this study, construction of an efficient NADPH-regenerating system was attempted using direct phosphorylation of NADH by NADH kinase (Pos5p) from Saccharomyces cerevisiae for producing guanosine diphosphate (GDP)-l-fucose and ε-caprolactone in recombinant Escherichia coli. Expression of Pos5p in a fed-batch culture of recombinant E. coli producing GDP-l-fucose resulted in a maximum GDP-l-fucose concentration of 291.5 mg/l, which corresponded to a 51 % enhancement compared with the control strain. In a fed-batch Baeyer–Villiger (BV) oxidation of cyclohexanone using recombinant E. coli expressing Pos5p, a maximum ε-caprolactone concentration of 21.6 g/l was obtained, which corresponded to a 96 % enhancement compared with the control strain. Such an increase might be due to the enhanced availability of NADPH in recombinant E. coli expressing Pos5p. These results suggested that efficient regeneration of NADPH was possible by functional expression of Pos5p in recombinant E. coli, which can be applied to other NADPH-dependent biotransformation processes in E. coli.  相似文献   
4.

Background

The association between sarcopenia and cardiovascular disease (CVD) in elderly people has not been adequately assessed. The aim of this study was to investigate whether CVD is more prevalent in subjects with sarcopenia independent of other well-established cardiovascular risk factors in older Korean adults.

Method

This study utilized the representative Korean population data from the Korea National Health and Nutrition Examination Survey (KNHANES) which was conducted in 2009. Subjects older than 65 years of age with appendicular skeletal muscle mass (ASM) determined by dual energy X-ray absorptiometry were selected. The prevalence of sarcopenia in the older Korean adults was investigated, and it was determined whether sarcopenia is associated with CVD independent of other well-known risk factors.

Results

1,578 subjects aged 65 years and older with the data for ASM were selected, and the overall prevalence of sarcopenia was 30.3% in men and 29.3% in women. Most of the risk factors for CVD such as age, waist circumference, body mass index, fasting plasma glucose and total cholesterol showed significant negative correlations with the ratio between appendicular skeletal muscle mass and body weight. Multiple logistic regression analysis demonstrated that sarcopenia was associated with CVD independent of other well-documented risk factors, renal function and medications (OR, 1.768; 95% CI, 1.075–2.909, P = 0.025).

Conclusions

Sarcopenia was associated with the presence of CVD independent of other cardiovascular risk factors after adjusting renal function and medications.  相似文献   
5.
Kim HC  Jhoo WK  Kim WK  Shin EJ  Cheon MA  Shin CY  Ko KH 《Life sciences》2001,69(8):915-922
We examined the effects of a non-opioid antitussive, carbetapentane (CB) on kainic acid (KA)-induced neurotoxicity in rats. KA administration (10 mg/kg, i.p.) produced robust behavioral convulsions lasting 4 to 5 h. CB (12.5 and 25 mg/kg. i.p.) pretreatment consistently and in a dose-dependent manner reduced the KA-induced seizures, mortality, and marked loss of cells in regions CA1 and CA3 of the hippocampus. Consistently, CB pretreatment also significantly attenuated the KA-induced increase in Fos-related antigen immunoreactivity in the hippocampus. In contrast, pretreatment with the sigma-1 receptor antagonist BD1047 (1 and 2 mg/kg, i.p.) blocked, in a dose-related manner, the neuroprotection afforded by CB. These results suggest that CB provides neuroprotection against KA insult via sigma-1 receptor modulation.  相似文献   
6.
Kwon KB  Kim JH  Lee YR  Lee HY  Jeong YJ  Rho HW  Ryu DG  Park JW  Park BH 《Life sciences》2003,73(2):181-191
We previously showed that Amomum xanthoides extract prevented alloxan-induced diabetes through the suppression of NF-kappaB activation. In this study, the preventive effects of A. xanthoides extract on cytokine-induced beta-cell destruction were examined. Cytokines produced by immune cells infiltrating pancreatic islets are important mediators of beta-cell destruction in insulin-dependent diabetes mellitus. A. xanthoides extract completely protected interleukin-1beta (IL-1beta) and interferon-gamma (IFN-gamma)-mediated cytotoxicity in rat insulinoma cell line (RINm5F). Incubation with A. xanthoides extract resulted in a significant reduction in IL-1beta and IFN-gamma-induced nitric oxide (NO) production, a finding that correlated well with reduced levels of the inducible form of NO synthase (iNOS) mRNA and protein. The molecular mechanism by which A. xanthoides extract inhibited iNOS gene expression appeared to involve the inhibition of NF-kappaB activation. Our results revealed the possible therapeutic value of A. xanthoides extract for the prevention of diabetes mellitus progression.  相似文献   
7.
Nordihydroguaiaretic acid (NDGA), an inhibitor of lipoxygenase, inhibits the secretion of proteins and causes the redistribution of resident Golgi proteins into the endoplasmic reticulum (ER). In this study, the effect of NDGA on lipoprotein lipase (LPL) secretion was investigated in 3T3-L1 adipocytes, and compared with those of brefeldin A (BFA), a well-known fungal metabolite that exhibits similar ER-Golgi redistribution. Both BFA and NDGA blocked secretions of LPL. In the presence of BFA, the active and dimeric LPL was accumulated in adipocytes. After endoglycosidase H (endo H) digestion, the proportion of LPL subunits with partially endo H-sensitive oligosaccharide was significantly increased with BFA. However, in the presence of NDGA, the cellular LPL became inactive, and only the endo H-sensitive fraction of the LPL subunit was observed. An increase of the aggregated forms was observed in the fractions of the sucrose-density gradient ultracentrifugation. These properties of LPL in the NDGA-treated cells were similar to those of LPL that is retained in ER, and the effects of NDGA could not be reversed by BFA. These results indicate that the inhibitory mechanism of NDGA on the LPL secretion is functionally different from the ER-Golgi redistribution that is induced by BFA.  相似文献   
8.
To investigate annual variation in soil respiration (R S) and its components [autotrophic (R A) and heterotrophic (R H)] in relation to seasonal changes in soil temperature (ST) and soil water content (SWC) in an Abies holophylla stand (stand A) and a Quercus-dominated stand (stand Q), we set up trenched plots and measured R S, ST and SWC for 2 years. The mean annual rate of R S was 436 mg CO2 m−2 h−1, ranging from 76 to 1,170 mg CO2 m−2 h−1, in stand A and 376 mg CO2 m−2 h−1, ranging from 82 to 1,133 mg CO2 m−2 h−1, in stand Q. A significant relationship between R S and its components and ST was observed over the 2 years in both stands, whereas a significant correlation between R A and SWC was detected only in stand Q. On average over the 2 years, R A accounted for approximately 34% (range 17–67%) and 31% (15–82%) of the variation in R S in stands A and Q, respectively. Our results suggested that vegetation type did not significantly affect the annual mean contributions of R A or R H, but did affect the pattern of seasonal change in the contribution of R A to R S.  相似文献   
9.
Rice bran and yeast extract were found to be the best combination of carbon and nitrogen sources for the production of carboxymethycellulase (CMCase) by Bacillus subtilis subsp. subtlis A-53. Optimal concentrations of rice bran and yeast extract for the production of CMCase were 5.0% (w/v) and 0.10% (w/v), respectively. Optimal temperature and initial pH of medium for cell growth of B. subtilus subsp. subtilis A-53 were 35 °C and 7.3, whereas those for the production of CMCase by B. subtilus subsp. subtilis A-53 were 30 °C and 6.8. Optimal agitation speed and aeration rate in a 7 L bioreactor were 300 rpm and 1.0 vvm, respectively. The optimal agitation speed and aeration rate for the production of CMCase by B. subtilus subsp. subtilis A-53 were lower than those for cell growth. The highest productions of CMCase by B. subtilus subsp. subtilis A-53 in 7 and 100 L bioreactors were 150.3 and 196.8 U mL−1, respectively.  相似文献   
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