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1.
2.
The effects of daily supplemental chromium (200 μg) complexed with 1.8 mg nicotinic acid on plasma glucose and lipids, including
total cholesterol, HDL cholesterol, LDL cholesterol, and triglycerides, were assessed in 14 healthy adults and 5 adults with
noninsulin-dependent diabetes mellitus (NIDDM) using a double-blind crossover study with 8-wk experimental periods. Eight
of the 14 healthy subjects and all 5 subjects with NIDDM also underwent an oral glucose tolerance test with assessment of
90 min postprandial plasma glucose and insulin concentrations. No statistically significant effects of chromium nicotinic
acid supplementation were found on plasma insulin, glucose, or lipid concentrations, although chromium nicotinic acid supplementation
slightly lowered fasting plasma total and LDL cholesterol, triglycerides, and glucose concentrations, and 90-min postprandial
glucose concentrations in individuals with NIDDM. 相似文献
3.
Plasma molybdenum concentrations were determined in children, ages two to 12 yr, with and without phenylketonuria (PKU). Mean
plasma molybdenum concentrations did not differ significantly between the children with PKU (1.33±0.5 μg/L) and without PKU
(1.75±0.8 μg/L). Plasma molybdenum concentrations in both groups of children ranged from <1 to 3 μg/L.
When data from all children were combined and then separated based on gender, mean plasma molybdenum levels did not differ
significantly between 9 females (1.56±0.68 μg/L) and 12 males (1.58±0.76 μg/L). Data were also combined and mean (±SD) plasma
molybdenum concentrations calculated for age groups. Two children aged 1 to <4 yr had plasma molybdenum concentrations of
1.0 μg/L, and six children aged 4 to <7 yr had mean (±SD) plasma molybdenum concentrations of 1.5±0.8 μg/L. Eleven children
aged 7 to <11 yr had a mean plasma molybdenum concentration of 1.7±0.7 μg/L, and two children 11 to <14 yr had plasma molybdenum
concentrations of 1 μg/L and 2 μg/L. Plasma molybdenum concentrations did not differ significantly among children in the age
groups. 相似文献
4.
Forskolin, an adenylate cyclase activator and a cyclic AMP analogue, dibutyryl cyclic AMP have been used to examine the relationship
between intracellular levels of cyclic AMP and lipid synthesis inMycobacterium smegmatis. Total phospholipid content was found to be increased in forskolin grown cells as a result of increased cyclic AMP levels
caused by activation of adenylate cyclase. Increased phospholipid content was supported by increased [14C] acetate incorporation as well as increased activity of glycerol-3-phosphate acyltransferase. Pretreatment of cells with
dibutyryl cyclic AMP had similar effects on lipid synthesis. Taking all these observations together it is suggested that lipid
synthesis is being controlled by cyclic AMP in mycobacteria. 相似文献
5.
Allison D. Ebert Brandon C. Shelley Amanda M. Hurley Marco Onorati Valentina Castiglioni Teresa N. Patitucci Soshana P. Svendsen Virginia B. Mattis Jered V. McGivern Andrew J. Schwab Dhruv Sareen Ho Won Kim Elena Cattaneo Clive N. Svendsen 《Stem cell research》2013,10(3):417-427
We have developed a simple method to generate and expand multipotent, self-renewing pre-rosette neural stem cells from both human embryonic stem cells (hESCs) and human induced pluripotent stem cells (iPSCs) without utilizing embryoid body formation, manual selection techniques, or complex combinations of small molecules. Human ESC and iPSC colonies were lifted and placed in a neural stem cell medium containing high concentrations of EGF and FGF-2. Cell aggregates (termed EZ spheres) could be expanded for long periods using a chopping method that maintained cell–cell contact. Early passage EZ spheres rapidly down-regulated OCT4 and up-regulated SOX2 and nestin expression. They retained the potential to form neural rosettes and consistently differentiated into a range of central and peripheral neural lineages. Thus, they represent a very early neural stem cell with greater differentiation flexibility than other previously described methods. As such, they will be useful for the rapidly expanding field of neurological development and disease modeling, high-content screening, and regenerative therapies based on pluripotent stem cell technology. 相似文献
6.
Background
Honey bee (Apis mellifera) drones and workers show differences in morphology, physiology, and behavior. Because the functions of drones are more related to colony reproduction, and those of workers relate to both survival and reproduction, we hypothesize that the microclimate for worker brood is more precisely regulated than that of drone brood.Methodology/Principal Findings
We assessed temperature and relative humidity (RH) inside honey bee colonies for both drone and worker brood throughout the three-stage development period, using digital HOBO® Data Loggers. The major findings of this study are that 1) both drone and worker castes show the highest temperature for eggs, followed by larvae and then pupae; 2) temperature in drones are maintained at higher precision (smaller variance) in drone eggs and larvae, but at a lower precision in pupae than the corresponding stages of workers; 3) RH regulation showed higher variance in drone than workers across all brood stages; and 4) RH regulation seems largely due to regulation by workers, as the contribution from empty honey combs are much smaller compared to that from adult workers.Conclusions/Significance
We conclude that honey bee colonies maintain both temperature and humidity actively; that the microclimate for sealed drone brood is less precisely regulated than worker brood; and that combs with honey contribute very little to the increase of RH in honey bee colonies. These findings increase our understanding of microclimate regulation in honey bees and may have implications for beekeeping practices. 相似文献7.
8.
Population‐based analysis of health care contacts among suicide decedents: identifying opportunities for more targeted suicide prevention strategies 下载免费PDF全文
Ayal Schaffer Mark Sinyor Paul Kurdyak Simone Vigod Jitender Sareen Catherine Reis Diane Green James Bolton Anne Rhodes Sophie Grigoriadis John Cairney Amy Cheung 《World psychiatry》2016,15(2):135-145
The objective of this study was to detail the nature and correlates of mental health and non‐mental health care contacts prior to suicide death. We conducted a systematic extraction of data from records at the Office of the Chief Coroner of Ontario of each person who died by suicide in the city of Toronto from 1998 to 2011. Data on 2,835 suicide deaths were linked with provincial health administrative data to identify health care contacts during the 12 months prior to suicide. Sub‐populations of suicide decedents based on the presence and type of mental health care contact were described and compared across socio‐demographic, clinical and suicide‐specific variables. Time periods from last mental health contact to date of death were calculated and a Cox proportional hazards model examined covariates. Among suicide decedents, 91.7% had some type of past‐year health care contact prior to death, 66.4% had a mental health care contact, and 25.3% had only non‐mental health contacts. The most common type of mental health contact was an outpatient primary care visit (54.0%), followed by an outpatient psychiatric visit (39.8%), an emergency department visit (31.1%), and a psychiatric hospitalization (21.0%). The median time from last mental health contact to death was 18 days (interquartile range 5‐63). Mental health contact was significantly associated with female gender, age 25‐64, absence of a psychosocial stressor, diagnosis of schizophrenia or bipolar disorder, past suicide attempt, self‐poisoning method and absence of a suicide note. Significant differences between sub‐populations of suicide decedents based on the presence and nature of their health care contacts suggest the need for targeting of community and clinical‐based suicide prevention strategies. The predominance of ambulatory mental health care contacts, often close to the time of death, reinforce the importance of concentrating efforts on embedding risk assessment and care pathways into all routine primary and specialty clinical care, and not only acute care settings. 相似文献
9.
The N-carbamoyl-
-amino acid amidohydrolase (
-carbamoylase) gene (dcb) from Agrobacterium tumefaciens AM 10 was cloned by polymerase chain reaction in plasmid pET28a and was overexpressed in Escherichia coli JM109 (DE3). However, almost 80% of the enzyme remained trapped in inclusion bodies. To facilitate the expression of the properly folded active enzyme, the chaperones GroEL/ES were coexpressed in plasmid pKY206. This resulted in a 43-fold increase in active enzyme production compared to the wild-type strain. The histidyl-tagged
-carbamoylase was purified by a single step nickel-affinity chromatography to a specific activity of 9.5 U/mg protein. 相似文献
10.
Jo Ishizawa Kensuke Kojima Teresa McQueen Vivian Ruvolo Dhruv Chachad Graciela M. Nogueras-Gonzalez Xuelin Huang William E. Pierceall E. J. Dettman Michael H. Cardone Sharon Shacham Marina Konopleva Michael Andreeff 《PloS one》2015,10(9)
BH3 profiling measures the propensity of transformed cells to undergo intrinsic apoptosis and is determined by exposing cells to BH3-mimicking peptides. We hypothesized that basal levels of prosurvival BCL-2 family proteins may modulate the predictive power of BH3 profiling and termed it mitochondrial profiling. We investigated the correlation between cell sensitivity to apoptogenic agents and mitochondrial profiling, using a panel of acute myeloid leukemias induced to undergo apoptosis by exposure to cytarabine, the BH3 mimetic ABT-199, the MDM2 inhibitor Nutlin-3a, or the CRM1 inhibitor KPT-330. We found that the apoptogenic efficacies of ABT-199 and cytarabine correlated well with BH3 profiling reflecting BCL2, but not BCL-XL or MCL-1 dependence. Baseline BCL-2 protein expression analysis increased the ability of BH3 profiling to predict resistance mediated by MCL-1. By utilizing engineered cells with overexpression or knockdown of BCL-2 family proteins, Ara-C was found to be independent, while ABT-199 was dependent on BCL-XL. BCL-2 and BCL-XL overexpression mediated resistance to KPT-330 which was not reflected in the BH3 profiling assay, or in baseline BCL-2 protein levels. In conclusion, mitochondrial profiling, the combination of BH3 profiling and prosurvival BCL-2 family protein analysis, represents an improved approach to predict efficacy of diverse agents in AML and may have utility in the design of more effective drug combinations. 相似文献