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101.
Androgens are important regulators of bone and prostate health in elderly men. The role of serum levels of glucuronidated androgen metabolites as predictors of BMD and prostate volume in men is unclear. We show that specific glucuronidated androgen metabolites predict BMD and prostate volume in elderly men. INTRODUCTION: Androgens are important regulators of bone and prostate health in elderly men. Local synthesis and degradation of androgens are likely to be important parameters of biological action of androgens in androgen-responsive tissues. The aim of this study was to determine the role of serum levels of glucuronidated androgen metabolites as predictors of BMD and prostate volume in elderly men. MATERIALS AND METHODS: A subsample of the population-based Swedish part of the MrOS study (n = 631, average age = 75.9 years) was investigated. Bone parameters were measured using DXA. Serum levels of total testosterone (T) and dihydrotestosterone (DHT) were measured by gas chromatography/mass spectroscopy (GC-MS); androstane-3alpha,17beta-diol-3glucuronide (3G) and androstane-3alpha,17beta-diol-17glucuronide (17G) were measured by liquid chromatography/mass spectroscopy. Prostate volume (n = 159) was measured by transrectal ultrasound. RESULTS: The general pattern is that two of the glucuronidated androgen metabolites, namely 17G and 3G, are stronger positive predictors of BMD than the bioactive androgens (T and DHT). In addition, 17G is a clear positive predictor of prostate volume, explaining 4.5% of the variance in prostate volume, whereas the bioactive androgens do not display any association with prostate volume. CONCLUSIONS: Serum levels of specific glucuronidated androgen metabolites predict BMD and prostate volume in elderly men. Future studies should determine if the glucuronidated androgen metabolites also reflect other biological correlates of androgenic activity, including prostate cancer, and if low levels might be a marker of general androgen deficiency in men.  相似文献   
102.
Background BMS-747158-02 is a novel fluorine 18-labeled pyridazinone derivative designed for cardiac imaging. The uptake and retention mechanisms of F-18 BMS-747158-02 in cardiac myocytes were studied in vitro, and the biodistribution of F-18 BMS-747158-02 was studied in vivo in mice. Methods and Results Fluorine 19 BMS-747158-01 inhibited mitochondrial complex I (MC-I) in bovine heart submitochondrial particles with an IC50 of 16.6±3 nmol/L that was comparable to the reference inhibitors of MC-1, rotenone, pyridaben, and deguelin (IC50 of 18.2±6.7 nmol/L, 19.8±2.6 nmol/L, and 23.1±1.5 nmol/L, respectively). F-18 BMS-747158-02 had high uptake in monolayers of neonatal rat cardiomyocytes (10.3%±0.7% of incubated drug at 60 minutes) that was inhibited by 200 nmol/L of rotenone (91%±2%) and deguelin (89%±3%). In contrast, an inactive pyridaben analog, P-0 (IC50 value>4 μmol/L in MC-1 assay), did not inhibit the binding of F-18 BMS-747158-02 in cardiomyocytes. Uptake and washout kinetics for F-18 BMS-747158-02 in rat cardiomyocytes indicated that the time to half-maximal (t1/2) uptake was very rapid (approximately 35 seconds), and washout t1/2 for efflux of F-18 BMS-747158-02 was greater than 120 minutes. In vivo biodistribution studies in mice showed that F-18 BMS-747158-02 had substatial myocardial uptake (9.5%±0.5% of injected dose per gram) at 60 minutes and heart-to-lung and heart-to-liver ratios of 14.1±2.5 and 8.3±0.5, respectively. Positron emission tomography imaging in the mouse allowed clear cardiac visualization and demonstrated sustained myocardial uptake through 55 minutes. Conclusions F-18 BMS-747158-02 is a novel positron emission tomography cardiac tracer targeting MC-I in cardiomyocytes with rapid uptake and slow washout. These characteristics allow fast and sustained accumulation in the heart.  相似文献   
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This commentary provides an evolutionary framework for the argument that motivation—goal striving—is central to animal and human life and governs most psychological processes, with implications for clinical practice. Neglect of clients' goals may seriously misdirect treatment; Systematic Motivational Counseling systematizes treatment of clients' motivational structure. Treatment of the consequences and determinants of clients' goals appears useful, as demonstrated in the case of alcohol abuse. The commentary then reexamines some currently popular goal-related concepts, particularly intrinsic versus extrinsic valuation and internality versus externality of goals, and argues for their reconceptualization on grounds that current conceptualizations have probably led to fallacious conclusions and may impair therapeutic effectiveness.  相似文献   
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Although the prevalence of cardiovascular complications is increased in insulin-resistant individuals, the underlying causes of this link have been elusive. Recent work suggests that several intracellular signal transduction pathways are inappropriately activated by hyperinsulinemia, hyperglycemia, increased free fatty acids, dyslipidemia, various inflammatory cytokines and adipokines--factors that are increased in insulin resistance. Once activated, substantial cross talk occurs between these pathways, especially a self-reinforcing cascade of vascular inflammation and cell dysfunction, greatly increasing the risk and severity of atherosclerosis in the insulin-resistant individual. We review several key cell-signalling pathways, describe how they are activated in they insulin-resistant state and the damage they induce, and discusses possible therapeutic approaches to limit vascular damage.  相似文献   
108.
OBJECTIVE: Interictal spikes in intracranial EEG (iEEG) may correlate with epileptogenic cortex, but review of interictal iEEG is labor intensive. Accurate automated spike detectors are necessary for understanding the role of spikes in epileptogenesis. METHODS: The sensitivity, accuracy and reproducibility of three automated iEEG spike detectors were compared against two human EEG readers using iEEG segments from eight patients. A consensus set of detections was generated for detector calibration. Spike verification was calculated after both human EEG readers independently reviewed all detections. RESULTS: Humans and two of the three automated detectors demonstrated comparable accuracy. In four patients, automated spike detection sensitivity was >70% and accuracy was >50%. In the remaining four patients, EEG background morphology resulted in poorer performance. Blinded human verification accuracy was 76.7+/-6.6% for computer-detected spikes, and 84.5+/-4.1% for human-detected spikes. CONCLUSIONS: Automated iEEG spike detectors perform comparably to humans, but sensitivity and accuracy are patient dependent. Humans verified the majority of computer-detected spikes. SIGNIFICANCE: In some patients automated detectors may be used for mapping spike occurrences in epileptic networks. This may reveal associations between spike distribution, seizure onset, and pathology.  相似文献   
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INTRODUCTION: Elderly patients who suffer trauma have a higher mortality and use disproportionately more trauma resources than younger patients. To compare these 2 groups and determine the outcomes and characteristics of elderly patients, we reviewed patients in these 2 groups admitted and treated in our tertiary care provincial trauma centre. METHODS: From the provincial trauma registry we selected a cohort of 40 geriatric patients (group 1) (> or = 65 yr of age) with an ISS of 16 or more who were admitted to and spent time in our trauma service for more than 48 hours and compared them with a similar randomly selected cohort of 44 patients (group 2) aged 20-30 years. Family physicians were contacted for follow-up of these patients 2 years after discharge. We considered length of hospital stay, complications, disposition of the patients and use of consultation services. RESULTS: Patients in group 1 had a mean age of 72.1 years (range from 65-98 yr) and a mean ISS of 27.3 (range from 17-50). Patients in group 2 had a mean age of 26.3 years (range from 22-29 yr) and a mean ISS of 26.3 (range from 17-54). Hospital stay was significantly longer in the group 1: 34.5 days (95% confidence interval [CI]: 24-44 d) versus 21.6 days (95% CI: 15-28 d). More elderly patients experienced complications (35 v. 13, p < 0.001) and required medical consultations (35 v. 26, p < 0.001). In-hospital death rates were 8% (3 of 40) and 4% (2 of 44) respectively (p = 0.3). Fewer geriatric patients could be discharged home (35% [14 of 40] v. 27% [22 of 44], p = 0.056) or to rehabilitation facilities (28% [11 of 40] v. 34% [15 of 44], p = 0.3). Five geriatric patients were discharged to nursing homes (p = 0.007). Of the geriatric patients discharged to rehabilitation facilities or home, 75% were independent 2 years after discharge. CONCLUSIONS: Aggressive care for geriatric trauma patients is warranted, and resources should be directed toward rehabilitation. Based on our findings, we expect that creating a directed care pathway for these patients, targetting complications and earlier discharge, will further improve their outcomes.  相似文献   
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