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931.
Subcutaneous adiposity and relative fat patterning in adult white and migrant asian males in Britain
A comparative study of subcutaneous adiposity and relative fat patterning in adult White (n=262) and migrant Indian (n=39)
and Pakistani (n=100) males living in Peterborough, Cambridgeshire revealed no significant difference in the level of generalised
adiposity (measured as body mass index) between the ethnic groups. However, Asians had significantly higher means for all
five truncal skinfolds; for all upper body: upper extremity, upper body: lower extremity, central body: upper extremity and
central body: lower extremity skinfold rations; more total subcutaneous adiposity; and significantly more subcutaneous fat
in subscapular, suprailiac and abdomen regions relative to total subcutaneous fat. However, Asian men had significantly less
subcutaneous fat in all the extremity sites relative to total subcutaneous adiposity and lower mean forearm subcutaneous adiposity.
Discriminant analysis revealed that 80.6% of all individuals were correctly classfied, with Whites being grouped more correctly
than Asians. Suprailiac/forearm and suprailiac/triceps skinfold ratios, height, weight, age, body mass index, and subscapular,
midauxillary, chest and medial calf skinfolds were among the most important discriminating variables/ratios of the three ethnic
groups. 相似文献
932.
A network of two neurons mutually coupled through inhibitory synapses that display short-term synaptic depression is considered. We show that synaptic depression expands the number of possible activity patterns that the network can display and allows for co-existence of different patterns. Specifically, the network supports different types of n-m anti-phase firing patterns, where one neuron fires n spikes followed by the other neuron firing m spikes. When maximal synaptic conductances are identical, n-n anti-phase firing patterns are obtained and there are conductance intervals over which different pairs of these solutions co-exist. The multitude of n-m anti-phase patterns and their co-existence are not found when the synapses are non-depressing. Geometric singular perturbation methods for dynamical systems are applied to the original eight-dimensional model system to derive a set of one-dimensional conditions for the existence and co-existence of different anti-phase solutions. The generality and validity of these conditions are demonstrated through numerical simulations utilizing the Hodgkin-Huxley and Morris-Lecar neuronal models. 相似文献
933.
Arpita Patel 《Soil & Sediment Contamination》2015,24(7):786-795
Chlorobenzene (CB), a dense nonaqeuous phase liquid (DNAPL), is categorized as a priority pollutant by the US EPA. It enters into ecosystems via solid and liquid waste discharge. Bioremediation is a key technique to remediate such contaminated sites. The present study aimed to isolate a chlorobenzene-degrading bacterium, determine the metabolic pathway for chlorobenzene degradation, and characterize biosurfactant production. Microbacterium sp. strain TAS1CB was isolated from contaminated sites and identified by 16S rRNA gene sequencing. Cells possessing positive chemotaxis for CB indicated their ability to degrade CB. Cells degraded CB via production of chlorobenzene dioxygenase, which converted CB to chlorocatechol. Chlorobenzene dioxygenase production was higher at 7 pH and 30°C. Intermediate metabolite analysis by UV scanning, HPLC, and GC-MS analysis revealed production of chlorocatechol and cis-cis muconate. Thus, Microbacterium was able to degrade CB via an ortho-cleavage pathway. In addition to chlorobenzene dioxygenase production, cells also produced biosurfactant which pseudosolubilized CB and increased degradation rate. Chemical characterization showed it to be a glycolipid-type biosurfactant. A phytotoxity study showed 60% of toxicity decreased after 72 hrs of degradation by isolate. 相似文献
934.
We used non‐insulin producing pancreatic carcinoma cell line, MIA PaCa‐2 and have modulated its culture conditions by using 1% matrigel as extracellular matrix, N2, B27 growth supplements and serum free conditions. Expression of markers was analyzed using qRT‐PCR, immunofluorescence and in vitro functional assay for insulin and C‐peptide release was assessed using insulin and C‐peptide ELISA, respectively. The cells grown under this altered culture conditions have exhibited a transition in the morphology from mesenchymal to epithelial with extensive piling up of cells. A reduction in doubling time from 40 to 18 h, upregulation of beta islet specific markers like pancreatic duodenal homeobox‐1 (Pdx‐1), C‐peptide, insulin, and disappearance of markers like vimentin were observed. On the functional level, the altered morphology bearing cells released high levels of insulin in response to 10 µM tolbutamide (an activator of insulin pathway) and reduced insulin secretion in response to 50 µM nifedipine (inhibitor of the pathway). On the contrary, the original cells (mesenchymal morphology) had failed to release any insulin in response to varying concentrations of glucose and also the activators and inhibitors of the insulin pathway. This investigation thus provides a basis for using this basic developmental biology phenomenon mesenchymal to epithelial transition as a strategy to generate a large number of functional islets from stem cells of mesenchymal origin. J. Cell. Biochem. 9999: XX–XX, 2013. © 2013 Wiley Periodicals, Inc. J. Cell. Biochem. 114: 1642–1652, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
935.
A cross-sectional study of 212 adult (>18 years) male slum dwellers (mean age=34.6+/-14.4 years) of Midnapore town, West Bengal, India, was undertaken to study the inter-relationships of chronic energy deficiency (CED), monthly family income (MFI), self-reported morbidity and hospitalization due to severe illness. The mean height, weight and body mass index (BMI) of the subjects were 160.0 cm, 50.8 kg and 19.9 kg/m2, respectively. The overall frequencies of CED (BMI<18.5 kg/m2), morbidity and hospitalization were 38.2%, 34.4% and 13.7%, respectively. Based on the WHO classification, the prevalence of CED among this population was high (20-39%), indicating a serious situation. Overall, MFI was significantly (p<0.01) positively correlated with BMI (r=0.21). Linear regression analyses showed that MFI had a significant impact (t=3.08; p<0.002) on BMI. Overall, MFI explained 3.9% variation in BMI. Subjects belonging to the lowest family income group (FIG I) had the lowest mean BMI (19.1 kg/m2) and the highest rate of CED (46.3%) and morbidity (36.6%). Those in the highest family income group (FIG III) had the largest mean BMI (20.8 kg/m2) and lowest rate of CED (30.2%) and morbidity (30.2%). The highest rate (18.9%) of hospitalization was found in this group. There were significant family income group differences in mean BMI (F=3.134, p<0.05). The frequency of morbidity (24.6%) and hospitalization (11.9%) was lowest among normal BMI individuals. Morbidity was significantly higher (chi2=11.92, p=0.0026) among CED (48.2%) subjects compared with normal BMI individuals (OR=2.85; CI=1.49-5.46). Similarly, compared with normal BMI subjects, morbidity was higher (38.5%; OR=1.92; 95% CI=0.50-7.18) among overweight subjects. Hospitalization was more common among CED subjects (16.1%; OR=1.42; CI=0.58-3.45) compared with normal BMI subjects. Similarly, the frequency of hospitalization was more among overweight individuals (15.4%; OR=1.35; 95% CI=0.0-7.59). In conclusion, this study provides evidence that the frequency of CED among this population is high, indicating a serious situation. Moreover there exists strong inter-relationships between BMI, CED, MFI and morbidity. 相似文献
936.
Glutamine, like glucose, repressed sporulation and the synthesis of mycobacillin and dipicolinic acid by Bacillus subtilis, and these syntheses were depressed by dibutyryl cyclic GMP but not by dibutyryl cyclic AMP. Neither of these dibutyryl cyclic nucleotides affected sporulation or a number of spore-associated parameters in the strain under normal physiological conditions. Mutants insensitive to glutamine repression were indifferent to the addition of either of the dibutyryl cyclic nucleotides both in the presence and in the absence of glutamine. Sporulation resulted from the remission of repression obtained under the catabolically active state. 相似文献
937.
938.
Improvements to solid phase phosphotriester synthesis of deoxyoligonucleotides. 总被引:4,自引:7,他引:4 下载免费PDF全文
T P Patel T A Millican C C Bose R C Titmas G A Mock M A Eaton 《Nucleic acids research》1982,10(18):5605-5620
A solution of benzenesulphonic acid (3%, w/v) in a dimethylformamide and dichloromethane mixture (9:1, v/v) is shown to be a very effective reagent for the detritylation of deoxyoligonucleotides attached to a solid support. The levels of depurination with this reagent were lower than those observed with other reagents such as trichloroacetic acid. Coupling reactions are described using above ambient temperatures with no detectable increase in side products. Both procedures have been successfully incorporated into an automated system, which can compete with the rate of synthesis by the phosphite approach. 相似文献
939.
Development of Nourseothricin N-acetyl transferase (NAT) as a selection marker for mammalian cells is described. Mammalian cells are acutely susceptible to Nourseothricin, similar to the widely used drug Puromycin, and NAT allows for quick and robust selection of transfected/transduced cells in the presence of Nourseothricin. NAT is compatible with other selection markers puromycin, hygromycin, neomycin, blasticidin, and is a valuable addition to the repertoire of mammalian selection markers. 相似文献
940.
Physiological Studies of Methane- and Methanol-Oxidizing Bacteria: Comparison of a Primary Alcohol Dehydrogenase from Methylococcus capsulatus (Texas Strain) and Pseudomonas Species M27 总被引:6,自引:6,他引:6 下载免费PDF全文
A primary alcohol dehydrogenase has been purified from Methylococcus capsulatus (Texas strain). The purified enzyme catalyzes the oxidation of methanol and formaldehyde to formate; other primary alcohols are oxidized to their corresponding aldehydes. Ammonium ions are required for enzyme activity. The enzyme has a molecular weight of 120,000 daltons and consists of two 62,000 molecular-weight subunits which dissociate at acidic pH. The enzyme is similar to an alcohol dehydrogenase enzyme isolated from Pseudomonas sp. M27. 相似文献