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91.
92.
The aim of our study was to evaluate whether corrected QT dispersion (QTc dispersion), an electrocardiographic marker, is a good predictor of the development of acute heart failure after high-dose chemotherapy followed by autologous or allogeneic hematopoietic stem cell transplantation. We enrolled 50 consecutive patients, from age 15 to 63 years, with hematopoietic diseases scheduled to undergo autologous or allogeneic hematopoietic stem cell transplantation, and compared QTc dispersion with other markers before transplantation conditioning. In univariate logistic analysis, QTc dispersion was a significant factor for acute heart failure after hematopoietic stem cell transplantation (odds ratio, 3.7 per 10 msec; confidence interval, 1.6-8.5; P = 0.002). There were no significant differences as age, sex, systolic or diastolic echocardiographic function markers, cumulative anthracycline dose, or QTc before transplantation between patients with and without acute heart failure. After multiple adjustments for left ventricular ejection fraction, cumulative anthracycline dose, cyclophosphamide conditioning dose, QTc dispersion was a significant and independent factor for acute heart failure after hematopoietic stem cell transplantation (odds ratio, 48.0 per 10 msec; confidence interval, 1.4-1666.3; P = 0.03). This study demonstrated that QTc dispersion could be used as a powerful noninvasive predictor of the development of acute heart failure after hematopoietic stem cell transplantation.  相似文献   
93.

Aims/hypothesis

The aim of this multicohort study was to examine whether employees exposed to social stressors at work, such as workplace bullying and violence, have an increased risk of type 2 diabetes.

Methods

The study included 45,905 men and women (40–65 years of age and free of diabetes at baseline) from four studies in Sweden, Denmark and Finland. Workplace bullying and violence were self-reported at baseline. Incident diabetes was ascertained through national health and medication records and death registers. Marginal structural Cox models adjusted for age, sex, country of birth, marital status and educational level were used for the analyses.

Results

Nine per cent of the population reported being bullied at work and 12% were exposed to workplace violence or threats of violence. Bullied participants had a 1.46 (95% CI 1.23, 1.74) times higher risk of developing diabetes compared with non-bullied participants. Exposure to violence or threats of violence was also associated with a higher risk of diabetes (HR 1.26 [95% CI 1.02, 1.56]). The risk estimates attenuated slightly when taking BMI into account, especially for bullying. The results were similar for men and women, and were consistent across cohorts.

Conclusions/interpretation

We found a higher risk of incident type 2 diabetes among employees exposed to bullying or violence in the workplace. Further research is needed to determine whether policies to reduce bullying and violence at work may reduce the incidence of type 2 diabetes in working populations. Research on the mechanisms is also highly warranted.
  相似文献   
94.

Aims/hypothesis

The progressive loss of beta cell function is part of the natural history of type 2 diabetes. Autopsy studies suggest that this is, in part, due to loss of beta cell mass (BCM), but this has not been confirmed in vivo. Non-invasive methods to quantify BCM may contribute to a better understanding of type 2 diabetes pathophysiology and the development of therapeutic strategies. In humans, the localisation of vesicular monoamine transporter type 2 (VMAT2) in beta cells and pancreatic polypeptide cells, with minimal expression in other exocrine or endocrine pancreatic cells, has led to its development as a measure of BCM. We used the VMAT2 tracer [18F]fluoropropyl-(+)-dihydrotetrabenazine to quantify BCM in humans with impaired glucose tolerance (prediabetes) or type 2 diabetes, and in healthy obese volunteers (HOV).

Methods

Dynamic positron emission tomography (PET) data were obtained for 4 h with metabolite-corrected arterial blood measurement in 16 HOV, five prediabetic and 17 type 2 diabetic participants. Eleven participants (six HOV and five with type 2 diabetes) underwent two abdominal PET/computed tomography (CT) scans for the assessment of test–retest variability. Standardised uptake value ratio (SUVR) was calculated in pancreatic subregions (head, body and tail), with the spleen as a reference region to determine non-specific tracer uptake at 3–4 h. The outcome measure SUVR minus 1 (SUVR-1) accounts for non-specific tracer uptake. Functional beta cell capacity was assessed by C-peptide release following standard (arginine stimulus test [AST]) and acute insulin response to the glucose-enhanced AST (AIRargMAX). Pearson correlation analysis was performed between the binding variables and the C-peptide AUC post-AST and post-AIRargMAX.

Results

Absolute test–retest variability (aTRV) was ≤15% for all regions. Variability and overlap of SUVR-1 was measured in all groups; HOV and participants with prediabetes and with type 2 diabetes. SUVR-1 showed significant positive correlations with AIRargMAX (all groups) in all pancreas subregions (whole pancreas p?=?0.009 and pancreas head p?=?0.009; body p?=?0.019 and tail p?=?0.023). SUVR-1 inversely correlated with HbA1c (all groups) in the whole pancreas (p?=?0.033) and pancreas head (p?=?0.008). SUVR-1 also inversely correlated with years since diagnosis of type 2 diabetes in the pancreas head (p?=?0.049) and pancreas tail (p?=?0.035).

Conclusions/interpretation

The observed correlations of VMAT2 density in the pancreas and pancreas regions with years since diagnosis of type 2 diabetes, glycaemic control and beta cell function suggest that loss of BCM contributes to deficient insulin secretion in humans with type 2 diabetes.
  相似文献   
95.
Postmortem examinations of the hypothalamus of patients with autosomal dominant neurohypophyseal diabetes insipidus (adNDI), which have been reported only on persons dying between the ages of 37-87 yr, reveal the presence of the arginine vasopressin (AVP)-producing parvocellular neurons but the absence of 95% of the expected AVP-producing magnocellular neurons. To determine whether the clinical course of adNDI is compatible with the hypothesis that the neuropathologic findings are attributable to a progressive loss of magnocellular neurons beginning in early life, we performed posterior pituitary magnetic resonance imaging and water deprivation tests, including plasma ACTH measurements, on 17 affected members of a kindred with the deltaE47 neurophysin mutation whose ages ranged from 3 months to 54 yr. Nine adult nonaffected members (ages, 20-56 yr) underwent these tests as controls. All six children undergoing magnetic resonance imaging demonstrated a posterior pituitary hyperintense signal (PPHS). Eight of nine affected adults showed an absent or barely visible PPHS, whereas eight of nine age-matched nonaffected adults produced a normal size PPHS. During water deprivation tests, infants concentrated their urine normally, and a 3-month-old infant produced a high plasma AVP level of 15.7 pmol/liter. By school age, affected children were no longer able to concentrate their urine or prevent hypernatremia. Affected adults became dehydrated; their median plasma AVP level was less than 1.0 pmol/liter, but their median fasting plasma ACTH was 2-fold greater than the level of nonaffected adults (10.0 vs. 5.0 pmol/liter; P = 0.008). These results suggest that adNDI is a progressive disease associated with chronic loss of the magnocellular neurons that supply AVP to the posterior pituitary but preservation of the parvocellular neurons that supply AVP and CRH to the median eminence and stimulate ACTH production during hypernatremia.  相似文献   
96.
RATIONALE: Restricting oxygen administration to those who benefit is desirable. OBJECTIVE: To determine the impact of alternative strategies for assessing eligibility for domiciliary oxygen on funded oxygen use, quality of life, and costs. METHODS: We randomized applicants for domiciliary oxygen therapy to an assessment system that relied on data collected by oxygen providers at the time of application and judgments by Home Oxygen Program personnel (conventional assessment) or to a system of data collection by a respiratory therapist that included, in patients unstable at the time of initial assessment, a repeat assessment after 2 months of stability (alternative assessment). MEASUREMENTS AND MAIN RESULTS: A total of 276 applicants were allocated to the conventional arm and 270 to the alternative assessment. In the year after application, oxygen use was lower in the alternative arm with no between-group differences in mortality, quality of life, or resource use in the community. Although alternative assessment applicants had on average higher assessment costs by dollars Canadian 155 per applicant, these costs were more than offset by decreased Home Oxygen Program costs of dollars Canadian 596 per applicant using Canadian cost weights. The comparable U.S. dollar figures were dollars US 309 and dollars US 432, respectively, and the difference in cost between strategies was therefore smaller using U.S. cost weights. CONCLUSIONS: Reassessment of applicants for domiciliary oxygen after several months of stability identifies an appreciable portion of initially eligible patients who are no longer eligible, thus reducing program costs to public funders without adverse consequences on quality of life, mortality, or other resource use.  相似文献   
97.
During prolonged viewing of ambiguous stimuli, such as Necker cubes, sudden perceptual reversals occur from one perceptual interpretation to another. The role of attention in such reversals is not clear. We tested whether perceptual reversals depend on attentional resources by manipulating perceptual load and recording event‐related potentials (ERPs) during intermittent presentation of Necker stimuli. The results did not reveal any influence for perceptual load on the frequency of reversals. The ERPs showed that perceptual load influenced electrophysiological activity over parieto‐central areas in the P1 time window (110–140 ms), but load did not modify the early enhancements of positivity (30–140 ms), which correlated with perceptual reversals at occipito‐temporal sites. We conclude that disambiguation of ambiguous figures is based on early mechanisms that can work efficiently with only a minimal amount of attentional resources.  相似文献   
98.

Background

Individual depressive symptoms may contribute to the risk of chronic depression. This study aimed to explore which symptoms predict chronic dysphoria, a hallmark of depression.

Methods

1057 participants from the population-based Young Finns study were examined for four times during a 16-year period. Those with a modified Beck’s Depression Inventory score in the upper third at all four screenings were considered to have chronic dysphoria (n=135). Participants with only one high depression score formed the reference group of transient dysphoria (n=179). Individual items of the Inventory were analyzed in terms of their association with dysphoria status and chronicity, controlling for potential confounding factors, such as personality assessed using the Temperament and Character Inventory.

Results

Body-image dissatisfaction was strongly associated with chronically elevated dysphoria (Bonferroni-corrected p=0.006). The degree of body-image dissatisfaction was associated with the probability for chronic dysphoria in a dose–response manner, with the estimated probability ranging from 0.01 to 0.60 as a function of item response. The association remained after adjustments for a wide range of personality characteristics.

Limitations

The study relied on self-reports of mood and personality, and lacked information on external opinion on participants appearances. The requirement of full time-series data may have resulted in attrition-related bias.

Conclusions

Body-image dissatisfaction was a strong predictor of chronic depression characterized by dysphoria. This finding suggests that dysfunctional attitude towards oneself might represent a potentially important target for cognitive therapies and preventive interventions.  相似文献   
99.
Speech recognition (SR) speeds patient care processes by reducing report turnaround times. However, concerns have emerged about prolonged training and an added secretarial burden for radiologists. We assessed how much proofing radiologists who have years of experience with SR and radiologists new to SR must perform, and estimated how quickly the new users become as skilled as the experienced users. We studied SR log entries for 0.25 million reports from 154 radiologists and after careful exclusions, defined a group of 11 experienced radiologists and 71 radiologists new to SR (24,833 and 122,093 reports, respectively). Data were analyzed for sound file and report lengths, character-based error rates, and words unknown to the SR’s dictionary. Experienced radiologists corrected 6 characters for each report and for new users, 11. Some users presented a very unfavorable learning curve, with error rates not declining as expected. New users’ reports were longer, and data for the experienced users indicates that their reports, initially equally lengthy, shortened over a period of several years. For most radiologists, only minor corrections of dictated reports were necessary. While new users adopted SR quickly, with a subset outperforming experienced users from the start, identification of users struggling with SR will help facilitate troubleshooting and support.  相似文献   
100.
Estradiol (E2) and progesterone (P4) are steroid hormones important for the regulation of immune responses during pregnancy. Their increasing levels coincide with an improvement of T cell-mediated diseases such as multiple sclerosis (MS). Although immune-endocrine interactions are involved in this phenomenon, the relative contribution of hormones is not known. We here report a direct comparison of E2- and P4-mediated effects on human CD4+ T cells, key cells in immune regulation. T cells were stimulated to obtain different activation levels and exposed to a broad range of hormone concentrations. Activation level was assessed by CD69/CD25 expression by flow cytometry, and secreted proteins (n = 196) were measured in culture supernatants using proximity extension assay and electrochemiluminescence immunoassay. We found that in low activated cells, pregnancy-relevant E2 concentrations increased activation and the secretion of several immune- and inflammation-related proteins. P4, on the other hand, showed a biphasic pattern, where serum-related concentrations upregulated activation and protein secretion while placenta-relevant concentrations induced a prominent dampening irrespective of the initial activation level. Our results demonstrate the importance of P4 as a major hormone in the immune modulation of T cells during pregnancy and emphasize the need to further evaluate its potency in the treatment of diseases like MS.  相似文献   
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