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Wongchawalit J Yamamoto T Nakai H Kim YM Sato N Nishimoto M Okuyama M Mori H Saji O Chanchao C Wongsiri S Surarit R Svasti J Chiba S Kimura A 《Bioscience, biotechnology, and biochemistry》2006,70(12):2889-2898
alpha-Glucosidase (JHGase I) was purified from a Japanese subspecies of eastern honeybee (Apis cerana japonica) as an electrophoretically homogeneous protein. Enzyme activity of the crude extract was mainly separated into two fractions (component I and II) by salting-out chromatography. JHGase I was isolated from component I by further purification procedure using CM-Toyopearl 650M and Sephacryl S-100. JHGase I was a monomeric glycoprotein (containing 15% carbohydrate), of which the molecular weight was 82,000. Enzyme displayed the highest activity at pH 5.0, and was stable up to 40 degrees C and in a pH-range of 4.5-10.5. JHGase I showed unusual kinetic features: the negative cooperative behavior on the intrinsic reaction on cleavage of sucrose, maltose, and p-nitrophenyl alpha-glucoside, and the positive cooperative behavior on turanose. We isolated cDNA (1,930 bp) of JHGase I, of which the deduced amino-acid sequence (577 residues) confirmed that JHGase I was a member of alpha-amylase family enzymes. Western honeybees (Apis mellifera) had three alpha-glucosidase isoenzymes (WHGase I, II, and III), in which JHGase I was considered to correspond to WHGase I. 相似文献
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The movement rates of sharks are intrinsically linked to foraging ecology, predator–prey dynamics and wider ecosystem functioning in marine systems. During ram ventilation, however, shark movement rates are linked not only to ecological parameters, but also to physiology, as minimum speeds are required to provide sufficient water flow across the gills to maintain metabolism. We develop a geometric model predicting a positive scaling relationship between swim speeds in relation to body size and ultimately shark metabolism, taking into account estimates for the scaling of gill dimensions. Empirical data from 64 studies (26 species) were compiled to test our model while controlling for the influence of phylogenetic similarity between related species. Our model predictions were found to closely resemble the observed relationships from tracked sharks, providing a means to infer mobility in particularly intractable species. 相似文献
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Geometric morphometry was used to characterize 73 Apis dorsata colonies collected from 31 different localities in five major geographic regions of mainland Thailand. We measured 19 easily identified landmarks from the digitized images of the right forewing of 10 worker bees from each colony (730 bees in total); thus, avoiding the confounding variation from haploid or diploid males. After plotting the factor scores, A. dorsata from (mainland) Thailand were found to belong to a single group, which was further supported by a hierarchical cluster analysis-generated dendrogram. Multivariate analysis of variance (MANOVA, α = 0.05) demonstrated no significant differences among the five geographic groups of A. dorsata in Thailand, producing a low degree of accuracy (31.2%) in the identification of the geographic region from which any individual bee originated. Additionally, when the bee samples were classified into two groups, those north and south of the Isthmus of Kra were not significantly different (MANOVA, α = 0.05), and a low rate of correct classification in a cross-validation test (65% correct) was found. Therefore, this geometric morphometric based analysis of worker bee wing venation pattern suggests that A. dorsata populations in mainland Thailand are panmictic. 相似文献
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Poonthrigpun S Pattaragulwanit K Paengthai S Kriangkripipat T Juntongjin K Thaniyavarn S Petsom A Pinphanichakarn P 《Applied and environmental microbiology》2006,72(9):6034-6039
The acenaphthylene-degrading bacterium Rhizobium sp. strain CU-A1 was isolated from petroleum-contaminated soil in Thailand. This strain was able to degrade 600 mg/liter acenaphthylene completely within three days. To elucidate the pathway for degradation of acenaphthylene, strain CU-A1 was mutagenized by transposon Tn5 in order to obtain mutant strains deficient in acenaphthylene degradation. Metabolites produced from Tn5-induced mutant strains B1, B5, and A53 were purified by thin-layer chromatography and silica gel column chromatography and characterized by mass spectrometry. The results suggested that this strain cleaved the fused five-membered ring of acenaphthylene to form naphthalene-1,8-dicarboxylic acid via acenaphthenequinone. One carboxyl group of naphthalene-1,8-dicarboxylic acid was removed to form 1-naphthoic acid which was transformed into salicylic acid before metabolization to gentisic acid. This work is the first report of complete acenaphthylene degradation by a bacterial strain. 相似文献
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Aekplakorn W Hogan MC Chongsuvivatwong V Tatsanavivat P Chariyalertsak S Boonthum A Tiptaradol S Lim SS 《Obesity (Silver Spring, Md.)》2007,15(12):3113-3121
Objective: To measure trends in the prevalence of overweight and obesity and the relationship with urban or rural residence and education in Thailand. Research Methods and Procedures: Data were from two nationally representative surveys of 38,323 individuals ≥18 years old (19,156 were 18 to 59 years old) in 2004 and 3375 individuals 18 to 59 years old in 1997. Overweight and obesity were defined using the World Health Organization's Asian criteria. Results: Among those ≥18 years old in 2004, 17.8% of men (95% confidence interval, 16.6% to 19.0%) were overweight, 18.4% (17.3% to 19.5%) had Class I obesity, 4.8% (4.1% to 5.5%) had Class II obesity, and 15.9% (14.6% to 17.1%) had abdominal obesity. In women, 18.2% (17.1% to 19.2%) were overweight, 26.1% (24.9% to 27.3%) had Class I obesity, 9.3% (8.6% to 10.0%) had Class II obesity, and 37.3% (35.3% to 39.2%) had abdominal obesity. In those 18 to 59 years old, the prevalence of Class I obesity in men and all four categories in women significantly increased between 1997 and 2004. There was an inverse relationship in women but a positive relationship in men between education and the odds of being overweight or obese. In 2004, there were significantly lower odds of being overweight or obese in rural compared with urban men but similar odds between urban and rural women. Discussion: The prevalence of overweight and obesity in Thailand is high and increasing. Although the transition of overweight and obesity to those of lower socioeconomic status is not complete, it is well on the way. 相似文献
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We examined worker reproduction in queenless and queenright Apis cerana colonies to determine if they are parasitized by workers from other nests. The results demonstrate that 2-6% of workers in queenright colonies are from another nest (non-natal), but these workers are not statistically more likely to have activated ovaries than natal workers, and are therefore unlikely to be active parasites. However, in queenless colonies we found a significant difference between the proportion of non-natal (72.7%) and natal (36.3%) workers with activated ovaries. Non-natal workers also had significantly higher reproductive success than natal workers: 1.8% of workers were non-natal, but these laid 5.2% of the eggs and produced 5.5% of the pupae. Unlike A. florea, the proportion of non-natal workers does not increase in queenless nests. 相似文献
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Saichin Isipradit Maytinee Sirimaharaj Puwat Charukamnoetkanok Oraorn Thonginnetra Warapat Wongsawad Busaba Sathornsumetee Sudawadee Somboonthanakij Piriya Soomsawasdi Umapond Jitawatanarat Wongsiri Taweebanjongsin Eakkachai Arayangkoon Punyawee Arame Chinsuchee Kobkoonthon Pannet Pangputhipong 《PloS one》2014,9(12)