214 research outputs found
Sensible heat transfer in the Gemini and Apollo pressure suits
Sensible heat transfer effects in Gemini and Apollo pressure suit
25-hydroxyvitamin D3 and 1,25-dihydroxyvitamin D3 exert distinct effects on human skeletal muscle function and gene expression
Age-associated decline in muscle function represents a significant public health burden. Vitamin D-deficiency is also prevalent in aging subjects, and has been linked to loss of muscle mass and strength (sarcopenia), but the precise role of specific vitamin D metabolites in determining muscle phenotype and function is still unclear. To address this we quantified serum concentrations of multiple vitamin D metabolites, and assessed the impact of these metabolites on body composition/muscle function parameters, and muscle biopsy gene expression in a retrospective study of a cohort of healthy volunteers. Active serum 1,25-dihydroxyvitamin D3 (1α,25(OH)2D3), but not inactive 25-hydroxyvitamin D3 (25OHD3), correlated positively with measures of lower limb strength including power (rho = 0.42, p = 0.02), velocity (Vmax, rho = 0.40, p = 0.02) and jump height (rho = 0.36, p = 0.04). Lean mass correlated positively with 1α,25(OH)2D3 (rho = 0.47, p = 0.02), in women. Serum 25OHD3 and inactive 24,25-dihydroxyvitamin D3 (24,25(OH)2D3) had an inverse relationship with body fat (rho = -0.30, p = 0.02 and rho = -0.33, p = 0.01, respectively). Serum 25OHD3 and 24,25(OH)2D3 were also correlated with urinary steroid metabolites, suggesting a link with glucocorticoid metabolism. PCR array analysis of 92 muscle genes identified vitamin D receptor (VDR) mRNA in all muscle biopsies, with this expression being negatively correlated with serum 25OHD3, and Vmax, and positively correlated with fat mass. Of the other 91 muscle genes analysed by PCR array, 24 were positively correlated with 25OHD3, but only 4 were correlated with active 1α,25(OH)2D3. These data show that although 25OHD3 has potent actions on muscle gene expression, the circulating concentrations of this metabolite are more closely linked to body fat mass, suggesting that 25OHD3 can influence muscle function via indirect effects on adipose tissue. By contrast, serum 1α,25(OH)2D3 has limited effects on muscle gene expression, but is associated with increased muscle strength and lean mass in women. These pleiotropic effects of the vitamin D ‘metabolome’ on muscle function indicate that future supplementation studies should not be restricted to conventional analysis of the major circulating form of vitamin D, 25OHD3
Cancer Treatment and Bone Health
Considerable advances in oncology over recent decades have led to improved survival, while raising concerns about long-term consequences of anticancer treatments. In patients with breast or prostate malignancies, bone health is a major issue due to the high risk of bone metastases and the frequent prolonged use of hormone therapies that alter physiological bone turnover, leading to increased fracture risk. Thus, the onset of cancer treatment-induced bone loss (CTIBL) should be considered by clinicians and recent guidelines should be routinely applied to these patients. In particular, baseline and periodic follow-up evaluations of bone health parameters enable the identification of patients at high risk of osteoporosis and fractures, which can be prevented by the use of bone-targeting agents (BTAs), calcium and vitamin D supplementation and modifications of lifestyle. This review will focus upon the pathophysiology of breast and prostate cancer treatment-induced bone loss and the most recent evidence about effective preventive and therapeutic strategies
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U.S. Fossil Fuel Technologies for Thailand
The US Department of Energy has been encouraging other countries to consider US coal and coal technologies in meeting their future energy needs. Thailand is one of three developing countries determined to be a potentially favorable market for such exports. This report briefly profiles Thailand with respect to population, employment, energy infrastructure and policies, as well as financial, economic, and trade issues. Thailand is shifting from a traditionally agrarian economy to one based more strongly on light manufacturing and will therefore require increased energy resources that are reliable and flexible in responding to anticipated growth. Thailand has extensive lignite deposits that could fuel a variety of coal-based technologies. Atmospheric fluidized-bed combustors could utilize this resource and still permit Thailand to meet emission standards for sulfur dioxide. This option also lends itself to small-scale applications suitable for private-sector power generation. Slagging combustors and coal-water mixtures also appear to have potential. Both new construction and refurbishment of existing plants are planned. 18 refs., 3 figs., 7 tabs
Harmonic publication and citation counting: sharing authorship credit equitably – not equally, geometrically or arithmetically
Bibliometric counting methods need to be validated against perceived notions of authorship credit allocation, and standardized by rejecting methods with poor fit or questionable ethical implications. Harmonic counting meets these concerns by exhibiting a robust fit to previously published empirical data from medicine, psychology and chemistry, and by complying with three basic ethical criteria for the equitable sharing of authorship credit. Harmonic counting can also incorporate additional byline information about equal contribution, or the elevated status of a corresponding last author. By contrast, several previously proposed counting schemes from the bibliometric literature including arithmetic, geometric and fractional counting, do not fit the empirical data as well and do not consistently meet the ethical criteria. In conclusion, harmonic counting would seem to provide unrivalled accuracy, fairness and flexibility to the long overdue task of standardizing bibliometric allocation of publication and citation credit
Statistical tools to improve assessing agreement between several observers
In the context of assessing the impact of management and environmental factors on animal health, behaviour or performance it has become increasingly important to conduct (epidemiological) studies in the field. Hence, the number of investigated farms per study is considerably high so that numerous observers are needed for investigation. In order to maintain the quality and validity of study results calibration meetings where observers are trained and the current level of agreement is assessed have to be conducted to minimise the observer effect. When study animals were rated independently by the same observers by a categorical variable the exclusion test can be performed to identify disagreeing observers. This statistical test compares for each variable and each observer the observer-specific agreement with the overall agreement among all observers based on kappa coefficients. It accounts for two major challenges, namely the absence of a gold-standard observer and different data type comprising ordinal, nominal and binary data. The presented methods are applied on a reliability study to assess the agreement among eight observers rating welfare parameters of laying hens. The degree to which the observers agreed depended on the investigated item (global weighted kappa coefficients: 0.37 to 0.94). The proposed method and graphical description served to assess the direction and degree to which an observer deviates from the others. It is suggested to further improve studies with numerous observers by conducting calibration meetings and accounting for observer bias
Cytologic features of nipple aspirate fluid using an automated non-invasive collection device: a prospective observational study
BACKGROUND: Detection of cytologic atypia in nipple aspirate fluid (NAF) has been shown to be a predictor of risk for development of breast carcinoma. Manual collection of NAF for cytologic evaluation varies widely in terms of efficacy, ease of use, and patient acceptance. We investigated a new automated device for the non-invasive collection of NAF in the office setting. METHODS: A multi-center prospective observational clinical trial involving asymptomatic women designed to assess fluid production, adequacy, safety and patient acceptance of the HALO NAF Collection System (NeoMatrix, Irvine, CA). Cytologic evaluation of all NAF samples was performed using previously described classification categories. RESULTS: 500 healthy women were successfully enrolled. Thirty-eight percent (190/500) produced fluid and 187 were available for cytologic analysis. Cytologic classification of fluid producers showed 50% (93/187) Category 0 (insufficient cellular material), 38% (71/187) Category I (benign non-hyperplastic ductal epithelial cells), 10% (18/187) Category II (benign hyperplastic ductal epithelial cells), 3% (5/187) Category III (atypical ductal epithelial cells) and none were Category IV (unequivocal malignancy). Overall, 19% of the subjects produced NAF with adequate cellularity and 1% were found to have cytologic atypia. CONCLUSION: The HALO system is a simple, safe, rapid, automated method for standardized collection of NAF which is acceptable to patients. Cytologic assessment of HALO-collected NAF showed the ability to detect benign and pre-neoplastic ductal epithelial cells from asymptomatic volunteers
Nipple aspiration and ductal lavage in women with a germline BRCA1 or BRCA2 mutation
INTRODUCTION: The aim of this study was to collect serial samples of nipple aspirate (NA) and ductal lavage (DL) fluid from women with germline BRCA1/2 mutations in order to create a biorepository for use in identifying biomarkers of breast cancer risk. METHODS: Between March 2003 and February 2005, 52 women with germline BRCA1 or BRCA2 mutations (median age 43 years, range 27 to 65 years) were scheduled for six-monthly NA, DL and venesection. DL was attempted for all NA fluid-yielding (FY) and any non-FY ducts that could be located at each visit. RESULTS: Twenty-seven (52%) women were postmenopausal, predominantly (19/27) from risk reducing bilateral salpingo-oophorectomy (BSO). FY ducts were identified in 60% of all women, 76% of premenopausal women versus 44% of postmenopausal (P = 0.026). Eighty-five percent of women had successful DL. Success was most likely in women with FY ducts (FY 94% versus non-FY 71% (P = 0.049). DL samples were more likely to be cellular if collected from FY ducts (FY 68% versus non-FY 43%; P = 0.037). Total cell counts were associated with FY status (FY median cell count 30,996, range 0 to >1,000,000 versus non-FY median cell count 0, range 0 to 173,577; P = 0.002). Four women (8%) had ducts with severe atypia with or without additional ducts with mild epithelial atypia; seven others had ducts with mild atypia alone (11/52 (21%) in total). Median total cell count was greater from ducts with atypia (105,870, range 1920 to >1,000,000) than those with no atypia (174, 0 to >1,000,000; P ≤ 0.001). CONCLUSION: It is feasible to collect serial NA and DL samples from women at high genetic risk of breast cancer, and we are creating a unique, prospective collection of ductal samples that have the potential to be used for discovery of biomarkers of breast cancer risk and evaluate the ongoing effects of risk reducing BSO. DL cellular atypia was not predictive of a current breast cancer and longer follow up is needed to determine whether atypia is an additional marker of future breast cancer risk in this population already at high genetic risk of breast cancer
Tolerability of breast ductal lavage in women from families at high genetic risk of breast cancer
<p>Abstract</p> <p>Background</p> <p>Ductal lavage (DL) has been proposed as a minimally-invasive, well-tolerated tool for obtaining breast epithelial cells for cytological evaluation of breast cancer risk. We report DL tolerability in <it>BRCA1/2 </it>mutation-positive and -negative women from an IRB-approved research study.</p> <p>Methods</p> <p>165 <it>BRCA1/2 </it>mutation-positive, 26 mutation-negative and 3 mutation unknown women underwent mammography, breast MRI and DL. Psychological well-being and perceptions of pain were obtained before and after DL, and compared with pain experienced during other screening procedures.</p> <p>Results</p> <p>The average <b><it>anticipated </it></b>and <b><it>experienced </it></b>discomfort rating for DL, 47 and 48 (0–100), were significantly higher (<it>p </it>< 0.01) than the <b><it>anticipated </it></b>and <b><it>experienced </it></b>discomfort of mammogram (38 and 34), MRI (36 and 25) or nipple aspiration (42 and 27). Women with greater pre-existing emotional distress experienced more DL-related discomfort than they anticipated. Women reporting DL-related pain as worse than expected were nearly three times more likely to refuse subsequent DL than those reporting it as the same or better than expected. Twenty-five percent of participants refused repeat DL at first annual follow-up.</p> <p>Conclusion</p> <p>DL was anticipated to be and experienced as <b>more </b>uncomfortable than other procedures used in breast cancer screening. Higher underlying psychological distress was associated with decreased DL tolerability.</p
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