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1.
K K Vaswani 《Life sciences》1985,37(12):1107-1115
Effects of neonatal thiamine deficiency and vitamin A deficiency on total and fractions of gangliosides (GT1, GD1a, GD1b and GM1) were studied in Charles Foster rat brain at 21 days of age. GT1, GD1b+GD1a and GM1 are being presented here as poly-, di- and mono-sialo gangliosides. Thiamine and vitamin A deficiencies were induced by feeding mothers essentially thiamine and vitamin A free diets respectively. A normal control (G+L+) and weight matched undernourished groups (G+L- for thiamine and LL for vitamin A experiments) were used for comparison. At 21 days, the concentration of total gangliosides in thiamine deficient and G+L- rat brains were 49.0% and 45.7%; in vitamin A deficient and LL group were 66.6% and 88.0% of the G+L+ group, respectively. The percent contribution of poly-, di- and mono-sialo gangliosides in G+L+/thiamine deficient/G+L- were; 17.2/46.8/73.5, 54.4/51.7/14.2, and 6.6/8.7/5.8, respectively. The percent contribution of poly-, di- and mono-sialo gangliosides in G+L+/vitamin A deficient/LL were; 19.3/39.9/43.7, 57.0/37.6/35.1, and 8.4/11.6/19.7 respectively. The changes observed in these experiments suggest an underlying possibility of metabolic defect in undernourished animals.  相似文献   
2.
This study was designed to explore the hormonal regulation of CNS opioid peptide levels in female Sprague Dawley rats. Forty-eight animals were divided into 2 equal groups for acute and chronic studies. Each group was further divided into 4 subgroups, each containing 6 animals. Each rat in the control group received an inert pill (in 0.25 ml corn oil daily by gavage); the second group, 15 micrograms norethindrone (NE, a potent progestin present in the oral contraceptive Micronor); the third group, 15 micrograms NE and 1 microgram ethinyl estradiol, EE2 (present in the oral contraceptive Modicon) and the fourth group, 10 times the dose of the third group. Rats were treated either acutely for 5 days or chronically for 7 weeks. Opioid peptides were estimated by radioimmunoassay. Acute administration of 150 micrograms NE + 10 micrograms EE2 decreased the levels of methionine-enkephalin (ME), leucine-enkephalin (LE), dynorphin (DYN) and beta-endorphin like immunoreactivity (beta-EI) by about 50% in the pituitary. The same dose on chronic administration also decreased DYN, but increased the levels of ME and LE in the pituitary by 331 and 69%, respectively. In the hypothalamus, chronic administration of NE + EE2 increased the level of ME (155%) and LE (87%) as well as of DYN (97%). In the striatum, the levels of LE (33%) and DYN (115%) were elevated during chronic administration. It is concluded that the acute administration of NE + EE2, in general, reduces the levels of ME, LE, DYN and beta-EI.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
It is of interest to evaluate the frequency of premolar extractions during orthodontic treatment in patients reporting to the Saveetha dental hospital in Chennai from 2019-2020. We used the records from 987 patients who underwent orthodontic treatment from June 2019 to March 2020 in a dental hospital for this analysis. Digital case records of patients who underwent therapeutic extractions of premolars were isolated. A sample dataset of 340 case records were selected for this study. Data shows that 34.4% of subjects underwent premolar extractions amongst a total of 987 subjects who underwent orthodontic treatment. 89.4% of patients were Angle''s Class I malocclusion patients, and the rest were Class II patients. However, no premolar extractions were done in Class III patients. Data also shows that 67.1% of subjects underwent all 4 first premolar extractions and 13.2% underwent only upper first premolar extractions. Thus, a significant association was found between Type of Malocclusion and the Type of premolar extractions with p < 0.05. Moreover, only 34.4% of patients underwent premolar extractions and the majority of them underwent all 4 first premolar extractions.  相似文献   
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5.
Biological Trace Element Research - This study was conducted to investigate the effect of vanadium (V) supplementation on growth, metabolism, antioxidant, and immunological and endocrine variables...  相似文献   
6.
Previous cross-sectional studies using delayed gamma neutron activation analysis and whole body counting suggested that the relationship of total body calcium (TBCa) to total body potassium (TBK) (muscle mass, body cell mass) remained constant with age. This led to the hypothesis that the muscle mass and skeletal mass compartments are integrated in their response to aging. It had also been hypothesized that loss of skeletal and muscle mass was similar between races. In the current study, delayed gamma neutron activation analysis and whole body counting were performed on 90 black and 143 white women 20-69 yr of age. Black women had higher TBCa and TBK values than white women, even when the data were adjusted for age, height, and weight. TBCa was correlated with height and TBK with weight. The estimated decline of skeletal mass (TBCa) from 20 to 70 yr was 18% in black women and 19% in white women. However, the lifetime decline of TBK was only 8% for black women, compared with 22% for white women. Black women may lose TBK more slowly than TBCa with aging, compared with white women. In particular, correlation of TBCa and age was similar for blacks and whites (r = -0.44 and r = -0.54, respectively). However, for TBK these correlations were r = -0.14 and r = -0.42. These data confirm a higher musculoskeletal mass in black women and suggest that the loss of muscle mass with age may be lower in black than in white women. These ethnic differences do not support the hypothesis of an integrated musculoskeletal system, so that these two components should be considered separately. A prospective study is needed to confirm these findings.  相似文献   
7.

Background

In Bangladesh, increases in cholera epidemics are being documented with a greater incidence and severity. The aim of this prospective study was to identify the prevalence and importance of V. cholerae O1 and enterotoxigenic Escherichia coli (ETEC) as causal agents of severe diarrhea in a high diarrhea prone urban area in Dhaka city.

Methodology

Systematic surveillance was carried out on all diarrheal patients admitted from Mirpur between March 2008 to February 2010 at the ICDDR, B hospital. Stool or rectal swabs were collected from every third diarrheal patient for microbiological evaluation.

Principal Findings

Of diarrheal patients attending the hospital from Mirpur, 41% suffered from severe dehydration with 39% requiring intravenous rehydration therapy. More diarrheal patients were above five years of age (64%) than those below five years of age (36%). About 60% of the patients above five years of age had severe dehydration compared with only 9% of patients under five years of age. The most prevalent pathogen isolated was Vibrio cholerae O1 (23%) followed by ETEC (11%). About 8% of cholera infection was seen in infants with the youngest children being one month of age while in the case of ETEC the rate was 11%. Of the isolated ETEC strains, the enterotoxin type were almost equally distributed; ST accounted for 31% of strains; LT/ST for 38% and LT for 31%.

Conclusion

V. cholerae O1 is the major bacterial pathogen and a cause of severe cholera disease in 23% of patients from Mirpur. This represents a socioeconomic group that best reflects the major areas of high cholera burden in the country. Vaccines that can target such high risk groups in the country and the region will hopefully be able to reduce the disease morbidity and the transmission of pathogens that impact the life and health of people.  相似文献   
8.
9.
Heat shock proteins (HSPs) are chaperones that are known to have important roles in facilitating protein synthesis, protein assembly and cellular protection. While HSPs are known to be induced by damaging exercise, little is known about how HSPs actually mediate skeletal muscle adaption to exercise. The purpose of this study was to determine the effects of a heat shock pretreatment and the ensuing increase in HSP expression on early remodeling and signaling (2 and 48 h) events of the soleus (Sol) muscle following a bout of downhill running. Male Wistar rats (10 weeks old) were randomly assigned to control, eccentric exercise (EE; downhill running) or heat shock + eccentric exercise (HS; 41°C for 20 min, 48 h prior to exercise) groups. Markers of muscle damage, muscle regeneration and intracellular signaling were assessed. The phosphorylation (p) of HSP25, Akt, p70s6k, ERK1/2 and JNK proteins was also performed. As expected, following exercise the EE group had increased creatine kinase (CK; 2 h) and mononuclear cell infiltration (48 h) compared to controls. The EE group had an increase in p-HSP25, but there was no change in HSP72 expression, total protein concentration, or neonatal MHC content. Additionally, the EE group had increased p-p70s6k, p-ERK1/2, and p-JNK (2 h) compared to controls; however no changes in p-Akt were seen. In contrast, the HS group had reduced CK (2 h) and mononuclear cell infiltration (48 h) compared to EE. Moreover, the HS group had increased HSP72 content (2 and 48 h), total protein concentration (48 h), neonatal MHC content (2 and 48 h), p-HSP25 and p-p70s6k (2 h). Lastly, the HS group had reduced p-Akt (48 h) and p-ERK1/2 (2 h). These data suggest that heat shock pretreatment and/or the ensuing HSP72 response may protect against muscle damage, and enhance increases in total protein and neonatal MHC content following exercise. These changes appear to be independent of Akt and MAPK signaling pathways.  相似文献   
10.
Sediment samples were collected from different estuarine and marine areas along the West coast of India. Eighteen actinomycete cultures were isolated using starch casein agar and were screened for polygalacturonase activity by growing them on pectin-agar plates. Clear zones were visualized using 1% cetrimide. Out of the 18 strains screened ten cultures could effect hydrolysis of pectin. The above cultures were subjected to secondary screening under submerged fermentation. The actinomycete strain of Streptomyces lydicus was found to be a potent producer of polygalacturonase. Different growth media were screened for enzyme production and the best medium was selected for further studies. The crude enzyme was used for the treatment of raw banana fibers.  相似文献   
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