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91.

On May 3, 2016, mandatory evacuation order was declared for Fort McMurray region as wildfire threatened. Over 90,000 residents were evacuated and firefighters from Canada and abroad worked constantly to protect the municipality. Overall, fire consumed about 2400 homes and over 200,000 ha of forest, reaching into Saskatchewan. The evacuation order was lifted with residents returning to the Municipality in phases from June 1, 2016. The aim of this study is to assess likely prevalence of PTSD in residents of Fort McMurray 6 months after a wildfire and to determine the predictors of likely PTSD in the respondents. A quantitative cross-sectional survey was used to collect data through self-administered paper-based questionnaires to determine likely PTSD. The PTSD Checklist for DSM 5 Part 3 was used to assess the presence or absence of likely PTSD in respondents randomly selected from a variety of natural settings in Fort McMurray. Data were analyzed with SPSS version 20 using univariate analysis with the chi-squared test and binary logistic regression analysis. One-month prevalence rate among adult residents for likely PTSD 6 months after the disaster was 12.8% (14.9% for females and 8.7% for males). While controlling for other factors in the logistic regression model, corresponding odds ratios included 9.51 and 4.88 for those who received no or only limited support respectively from friends/family, 8.00 for those who had history of an anxiety disorder before the wildfire, and 4.01 for those who received counseling after the wildfire. Respondents who presented with likely PTSD were significantly more likely to self-report increased drug abuse, but not increased alcohol use, after the fire. Our study has established that while support from family/friends following wildfires may be protective against likely PTSD, a prior diagnosis of an anxiety disorder significantly increased risk for developing PTSD. Further studies are needed to explore whether receiving counseling after a wild fire alters the likelihood of individuals presenting with PTSD.

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Immunological parameters that distinguish solid-organ transplant (SOT) recipients at risk for life-threatening cytomegalovirus (CMV) disease are being actively pursued to aid posttransplant management. A candidate marker is programmed death (PD)-1 receptor, whose overexpression has been associated with disease progression during persistent viral infections. To determine whether levels of this negative regulator of T cell activity are altered in SOT recipients with symptoms of CMV disease, a comparative PD-1 expression analysis was done in healthy, CMV-positive individuals and in liver transplant recipients. PD-1 levels were measured among the total population of CD8(+) and CD8(+) T cells binding to CMV-specific major histocompatibility complex class I tetramers. Minimal PD-1 expression was found in the healthy, CMV-positive cohort, and symptomatic SOT recipients had significantly higher PD-1 levels. PD-1 up-regulation was significantly associated with incipient and overt CMV disease and with viremia. Our findings suggest that PD-1 could be developed as a prognostic tool to predict CMV disease and guide therapeutic interventions.  相似文献   
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Background

Contemporary reconsideration of diagnostic N-terminal pro–B-type natriuretic peptide (NT-proBNP) cutoffs for diagnosis of heart failure (HF) is needed.

Objectives

This study sought to evaluate the diagnostic performance of NT-proBNP for acute HF in patients with dyspnea in the emergency department (ED) setting.

Methods

Dyspneic patients presenting to 19 EDs in North America were enrolled and had blood drawn for subsequent NT-proBNP measurement. Primary endpoints were positive predictive values of age-stratified cutoffs (450, 900, and 1,800 pg/ml) for diagnosis of acute HF and negative predictive value of the rule-out cutoff to exclude acute HF. Secondary endpoints included sensitivity, specificity, and positive (+) and negative (?) likelihood ratios (LRs) for acute HF.

Results

Of 1,461 subjects, 277 (19%) were adjudicated as having acute HF. The area under the receiver-operating characteristic curve for diagnosis of acute HF was 0.91 (95% confidence interval [CI]: 0.90 to 0.93; p < 0.001). Sensitivity for age stratified cutoffs of 450, 900, and 1,800 pg/ml was 85.7%, 79.3%, and 75.9%, respectively; specificity was 93.9%, 84.0%, and 75.0%, respectively. Positive predictive values were 53.6%, 58.4%, and 62.0%, respectively. Overall LR+ across age-dependent cutoffs was 5.99 (95% CI: 5.05 to 6.93); individual LR+ for age-dependent cutoffs was 14.08, 4.95, and 3.03, respectively. The sensitivity and negative predictive value for the rule-out cutoff of 300 pg/ml were 93.9% and 98.0%, respectively; LR? was 0.09 (95% CI: 0.05 to 0.13).

Conclusions

In acutely dyspneic patients seen in the ED setting, age-stratified NT-proBNP cutpoints may aid in the diagnosis of acute HF. An NT-proBNP <300 pg/ml strongly excludes the presence of acute HF.  相似文献   
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Dynamics of tyrosine hydroxylase (TH) was studied in various brain regions and pituitary in relation to annual/seasonal and circadian variations in either sex of the catfish Heteropneustes fossilis. alpha-Methylparatyrosine inhibited TH activity significantly in a time-(in vivo study) and concentration-(in vitro study) dependent manner. The inhibition was higher in resting phase than preparatory phase and in females than males (time-course study). The apparent kinetic constant of inhibition (K(i)) varied both seasonally and regionally. The values were higher in resting phase and in the forebrain regions (telencephalon and hypothalamus) than medulla oblongata. No significant sex difference was noticed in the K(i) values in the same season. TH activity showed significant annual/seasonal variations with telencephalon and hypothalamus showing higher activity than medulla oblongata. The females showed significantly higher enzyme activity than males with a distinct activity peak in June (prespawning phase). Such an activity peak was apparently absent in males. TH activity showed significant circadian/diurnal variations, the highest activity was noticed at 12 h and the lowest at 24 h. The apparent Michaelis-Menten constant (K(m)) values (hypothalamic TH) for substrate (L-tyrosine) and cofactor (DMPH(4)) showed seasonal variations with the highest values in the resting phase, decreasing through preparatory and prespawning phases, to the lowest values in spawning phase. V(max) was the lowest in the resting phase and highest in the spawning phase. TH activity was low in the pituitary and could be detected in pooled samples from March (preparatory phase) to July (spawning phase). Activity showed significant variations, which could be correlated with the gonadosomatic index. The results show that TH activity could be positively correlated with the annual reproductive cycle. The enzyme activity could be also correlated with seasonal, sex, and regional variations in the apparent K(m) and V(max) values suggesting apparent differences in the affinity of the enzyme towards substrate and cofactor.  相似文献   
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