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21.

Introduction

The relationship between hyperoxemia and outcome in patients with traumatic brain injury (TBI) is controversial. We sought to investigate the independent relationship between hyperoxemia and long-term mortality in patients with moderate-to-severe traumatic brain injury.

Methods

The Finnish Intensive Care Consortium database was screened for mechanically ventilated patients with a moderate-to-severe TBI. Patients were categorized, according to the highest measured alveolar-arterial O2 gradient or the lowest measured PaO2 value during the first 24 hours of ICU admission, to hypoxemia (<10.0 kPa), normoxemia (10.0 to 13.3 kPa) and hyperoxemia (>13.3 kPa). We adjusted for markers of illness severity to evaluate the independent relationship between hyperoxemia and 6-month mortality.

Results

A total of 1,116 patients were included in the study, of which 16% (n = 174) were hypoxemic, 51% (n = 567) normoxemic and 33% (n = 375) hyperoxemic. The total 6-month mortality was 39% (n = 435). A significant association between hyperoxemia and a decreased risk of mortality was found in univariate analysis (P = 0.012). However, after adjusting for markers of illness severity in a multivariate logistic regression model hyperoxemia showed no independent relationship with 6-month mortality (hyperoxemia vs. normoxemia OR 0.88, 95% CI 0. 63 to 1.22, P = 0.43; hyperoxemia vs. hypoxemia OR 0.97, 95% CI 0.63 to 1.50, P = 0.90).

Conclusion

Hyperoxemia in the first 24 hours of ICU admission after a moderate-to-severe TBI is not predictive of 6-month mortality.  相似文献   
22.
Germline mutations in the fumarate hydratase (FH) gene at 1q43 predispose to dominantly inherited cutaneous and uterine leiomyomas, uterine leiomyosarcoma, and papillary renal cell cancer (HLRCC syndrome). To evaluate the role of FH inactivation in sporadic tumorigenesis, we analyzed a series of 299 malignant tumors representing 10 different malignant tumor types for FH mutations. Additionally, 153 uterine leiomyomas from 46 unselected individuals were subjected to and informative in loss of heterozygosity analysis at the FH locus, and the five (3.3%) tumors displaying loss of heterozygosity were subjected to FH mutation analysis. Although mutation search in the 299 malignant tumors was negative, somatic FH mutations were found in two nonsyndromic leiomyomas; a splice site change IVS4 + 3A>G, leading to deletion of exon four, and a missense mutation Ala196Thr. The occurrence of somatic mutations strongly suggests that FH is a true target of the 1q43 deletions. Although uterine leiomyomas are the most common tumors of women, specific inactivating somatic mutations contributing to the formation of nonsyndromic leiomyomas have not been reported previously. Taking into account the apparent risk of uterine leiomyosarcoma associated with FH germline mutations, the finding raises the possibility that also some nonsyndromic leiomyomas may have a genetic profile that is more prone to malignant degeneration. Our data also indicate that somatic FH mutations appear to be limited to tumor types observed in hereditary leiomyomatosis and renal cell cancer.  相似文献   
23.
A key question in precision medicine is how functional heterogeneity in solid tumours informs therapeutic sensitivity. We demonstrate that spatial characteristics of oncogenic signalling and therapy response can be modelled in precision‐cut slices from Kras‐driven non‐small‐cell lung cancer with varying histopathologies. Unexpectedly, profiling of in situ tumours demonstrated that signalling stratifies mostly according to histopathology, showing enhanced AKT and SRC activity in adenosquamous carcinoma, and mitogen‐activated protein kinase (MAPK) activity in adenocarcinoma. In addition, high intertumour and intratumour variability was detected, particularly of MAPK and mammalian target of rapamycin (mTOR) complex 1 activity. Using short‐term treatment of slice explants, we showed that cytotoxic responses to combination MAPK and phosphoinositide 3‐kinase–mTOR inhibition correlate with the spatially defined activities of both pathways. Thus, whereas genetic drivers determine histopathology spectra, histopathology‐associated and spatially variable signalling activities determine drug sensitivity. Our study is in support of spatial aspects of signalling heterogeneity being considered in clinical diagnostic settings, particularly to guide the selection of drug combinations. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.  相似文献   
24.
Data on neurobiological differences between major depression (MD) and double depression (DD) are scarce. We examined the striatum dopamine (DAT) and midbrain serotonin transporter (SERT) binding of [123I] nor-β-CIT in DD patients (n = 8) and compared it to that in MD patients (n = 11) and healthy controls (n = 19). Drug-naïve patients and controls were imaged by single-photon emission computed tomography at baseline, and the patients also after one year of psychodynamic psychotherapy. Both DD and MD groups had lower midbrain [123I] nor-β-CIT binding compared with the controls. Baseline 17-item Hamilton Depression Rating Scale (HAM-D-17) scores significantly decreased in both groups after one year of psychotherapy (DD: t = 3.55, p = 0.009; MD: t = 5.86, p < 0.001). No differences between the DD and MD groups were observed in age-adjusted baseline striatum or midbrain [123I] nor-β-CIT binding or its change during psychotherapy. Age-adjusted baseline striatum [123I] nor-β-CIT binding correlated inversely with the duration of both dysthymia (rho = −0.76, p = 0.03) and MD (rho = −0.83, p = 0.01) in the DD group. No such finding was observed in the MD group (rho = 0.26, p = 0.44). Baseline HAM-D-17 did not correlate with the change in striatum or midbrain [123I] nor-β-CIT binding in either group. In conclusion, our findings suggest that when using midbrain [123I] nor-β-CIT binding as a marker of SERT binding, no differences are detectable between patients with DD and MD. However, low striatum [123I] nor-β-CIT binding, a marker of DAT binding, may be associated with a longer illness duration in dysthymia.  相似文献   
25.
BackgroundVulvovaginal candidiasis (VVC) is the second most common infection of the genital tract affecting millions of women worldwide. Data concerning the distribution and antifungal resistance of Candida species responsible of VVC vary among countries and population studied. Objectives: The aim of this work was to determine the prevalence, species distribution and antifungal susceptibility patterns of Candida species among symptomatic women over a 20-year period.MethodsA total of 5,820 unique samples were retrospectively identified. Out of them, 1,046 (18%) were diagnosed with VVC.ResultsWomen between 18 and 30 years had the highest prevalence rate of VVC (21%). Women aged less than 18 years and greater than 51 years had the highest prevalence rates of vaginal bacterial infections. Thirty-five (3.3%) women presented recurrent VVC. The most common yeast isolated was C. albicans, followed by C. glabrata, C. krusei, and C. parapsilosis. Non-Candida albicans species (NAC) were more significantly isolated among women aged 51 or above, than in women included in other groups (p < 0.01). Resistance to fluconazole and amphotericin B was infrequent in C. albicans strains. Resistance to fluconazole and amphotericin B was infrequent in C. albicans strains. NAC species presented higher resistance rates against fluconazole (30%) and voriconazole (25%). C. krusei and C. glabrata isolates showed lower MICs than most of the strains against amphotericin B (1 mg/L) and flucytosine (1 mg/L).ConclusionsOur findings indicated that continued surveillance on Candida species distribution and non-susceptibility rates to antifungals should be routinely reported to help the selection of the most appropriate drug, to avoid the emergence of resistant strains, and to improve the patient's outcomes.  相似文献   
26.
The aim of this study was to develop a rapid and simple flow cytometric bacterial infection marker. In this prospective comparative study, quantitative flow cytometric analysis of CD10, CD35, CD66b, CD282, and MHC Class I molecules on human neutrophils, monocytes, and B-lymphocytes from 141 hospitalized febrile patients with suspected infection and from 50 healthy controls was performed. We developed a flow cytometric marker of local and systemic bacterial infections, designated “bacterial infection (BI)-INDEX”, incorporating the quantitative analysis of CD10, CD35, MHCI, CD66b, and CD282 on neutrophils, monocytes, and B-lymphocytes, which displayed 90% sensitivity and 96% specificity in distinguishing between microbiologically confirmed bacterial (n = 31) and viral infections (n = 27) within a 1-h time-frame. We propose that our novel rapid BI-INDEX test will be useful in assisting physicians to ascertain whether antibiotic treatment is required, thus limiting unnecessary antimicrobial usage.  相似文献   
27.
28.

Background  

Relatively little is known about the significance of normal variation in objectively assessed sleep duration and its regularity in children's psychological well-being.  相似文献   
29.
Autosomal-inherited progressive external ophthalmoplegia (PEO) is an adult-onset disease characterized by the accumulation of multiple mitochondrial DNA (mtDNA) deletions in post-mitotic tissues. Mutations in six different genes have been described to cause the autosomal dominant form of the disease, but only mutations in the DNA polymerase gamma gene are known to cause autosomal recessive PEO (arPEO), leaving the genetic background of arPEO mostly unknown. Here we used whole-exome sequencing and identified compound heterozygous mutations, leading to two amino acid alterations R225W and a novel T230A in thymidine kinase 2 (TK2) in arPEO patients. TK2 is an enzyme of the mitochondrial nucleotide salvage pathway and its loss-of-function mutations have previously been shown to underlie the early-infantile myopathic form of mtDNA depletion syndrome (MDS). Our TK2 activity measurements of patient fibroblasts and mutant recombinant proteins show that the combination of the identified arPEO variants, R225W and T230A, leads to a significant reduction in TK2 activity, consistent with the late-onset phenotype, whereas homozygosity for R225W, previously associated with MDS, leads to near-total loss of activity. Our finding identifies a new genetic cause of arPEO with multiple mtDNA deletions. Furthermore, MDS and multiple mtDNA deletion disorders are manifestations of the same pathogenic pathways affecting mtDNA replication and repair, indicating that MDS-associated genes should be studied when searching for genetic background of PEO disorders.  相似文献   
30.

Background

Sleep duration has been shown to be associated with all-cause mortality; however, its relationship with cause-specific fatal events remains uncertain. We examined the relationship between sleep duration and risk of fatal coronary heart disease, sudden cardiac death, cancer-related death, and all-cause mortality.

Methods

Sleep duration was self-reported at baseline examinations performed between March 20, 1984, and December 5, 1989, in 2361 men aged 42-61 years from the Kuopio Ischemic Heart Disease study. Of these, 1734 (73.4%) men were free from coronary heart disease and cancer at baseline.

Results

A total of 802 all-cause deaths, 202 fatal coronary heart disease events, 141 sudden cardiac events, and 229 cancer-related deaths were reported during a median follow-up of 25.9 (interquartile range, 20.6-28.2) years. Multivariable adjusted hazard ratios comparing the top quartile (>10 hours) of sleep duration vs the bottom quartile (<8 hours) was 1.19 (95% confidence interval [CI], 1.01-1.43) for all-cause mortality, 1.27 (95% CI, 0.88-1.84) for fatal coronary heart disease, 1.20 (95% CI, 0.78-1.86) for sudden cardiac death, and 1.29 (95% CI, 0.92-1.80) for cancer death. No differences in association of sleep duration with outcomes were found in clinically relevant subgroups, including age, history of coronary heart disease, body mass index, physical activity, and C-reactive protein levels.

Conclusions

Longer duration of sleep was associated with significantly increased all-cause mortality. The mechanistic link between these findings remains to be explored further.  相似文献   
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