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Background
The factors determining peak susceptibility of the developing brain to anaesthetics are unclear. It is unknown why postnatal day 7 (P7) male rats are more vulnerable to anaesthesia-induced memory deficits than littermate females. Given the precocious development of certain regions in the female brain during the neonatal critical period, we hypothesised that females are susceptible to anaesthetic brain injury at an earlier time point than previously tested.Methods
Female rats were exposed to isoflurane (Iso) 1 minimum alveolar concentration or sham anaesthesia at P4 or P7. Starting at P35, rats underwent a series of behavioural tasks to test their spatial and recognition memory. Cell death immediately after anaesthesia was quantified by Fluoro-Jade C staining in select brain regions, and developmental expression of the chloride transporters KCC2 and NKCC1 was analysed by immunoblotting in male and female rats at P4 and P7.Results
Female rats exposed to Iso at P4 displayed impaired spatial, object-place, -context, and social recognition memory, and increased cell death in the hippocampus and laterodorsal thalamus. Female rats exposed at P7 exhibited only decreased performance in object-context compared with control. The ratio of NKCC1/KCC2 expression in cerebral cortex was higher in P4 females than in P7 females, and similar to that in P7 males.Conclusions
Female rats exposed to Iso at P4 are sensitive to anaesthetic injury historically observed in P7 males. This is consistent with a comparably immature developmental state in P4 females and P7 males. The window of anaesthetic vulnerability correlates with sex-specific cortical expression of chloride transporters NKCC1 and KCC2. These findings suggest that both sex and developmental age play important roles in determining the outcome after early anaesthesia exposure. 相似文献Study objectives
The primary objective of this study was to compare Emergency Department patients with first-time versus recurrent acute pancreatitis.Methods
This study was a retrospective chart review of patients with a diagnosis of acute pancreatitis who presented to a single academic urban emergency department from 2012 to 2016. Criteria for inclusion were clinical symptoms of pancreatitis, age greater than or equal to 18?years, ED diagnosis of acute pancreatitis, and an abdominal CT scan within 24?h of triage. Exclusion criteria were traumatic mechanism and pregnancy. Charts were reviewed by a minimum of two trained abstractors using structured data collection sheets and discrepancies were resolved by a third abstractor. Patients with first time acute pancreatitis versus recurrent acute pancreatitis were compared to determine differences in characteristics, management and disposition.Results
250 patients were included in the study. Of these, 165 patients had first-time acute pancreatitis and 85 patients had recurrent acute pancreatitis. Demographics, vital signs and initial lab values were the same in both groups. Patients with recurrent acute pancreatitis were more likely to have significant findings on CT (Modified CT Severity Index, 2.09 versus 1.43, p?<?0.05), more likely to require IV opiates (96% versus 75%, p?<?0.001) and less likely to need ICU admission (8% versus 19%, p?=?0.03).Conclusion
ED patients with recurrent acute pancreatitis demonstrated more significant findings on CT compared to patients with first-time acute pancreatitis but were less likely to require ICU admission. 相似文献Objective
To assess the impact of focality and location of positive surgical margins (PSM) on long-term outcomes after radical prostatectomy (RP) for prostate cancer (PCa), including biochemical recurrence (BCR), metastasis and overall mortality.Patients and Methods
From a total of 2796 cases of RP between 1993 and 2007 in our single hospital, 476 cases with PSMs were identified and included in this study. PSM location was categorized into apex, peripheral, and bladder neck. Survival was estimated using the Kaplan-Meier method. Cox proportional hazard regression models were used to analyze the impact of PSM focality and location status on oncologic survival.Results
Of these 476 cases with PSMs, 335 (70.4%) cases were with single focal (sF) PSMs and 141 (29.6%) cases were with multifocal (mF) PSMs. Furthermore, 406 (85.3%) cases were found to have single location (sL) PSMs, and 70 (14.7%) cases were with multilocation (mL) PSMs. The median follow-up was 12.9 years. mF-PSMs and mL-PSMs showed significant impact on increased BCR risk on univariate analysis, and mL-PSMs remained significant on multivariate analysis (P = .048). Furthermore, the combination of multifocality and multilocation showed added prognostic value on predicting BCR-free survival, but not on metastasis-free survival or overall survival.Conclusion
The presence of mF-PSMs and mL-PSMs, and especially the combination of both, demonstrated significant impact on BCR prognosis. Patients with apex sLsF-PSMs were less likely to have BCR when compared with all those with non-apex sLsF-PSMs. These results should be considered when evaluating patients for adjuvant therapy. 相似文献- KEY MESSAGES
Numerous recent publications have examined the relation between cardiovascular disease and long-term blood pressure (BP) exposure, quantified using indices such as time-averaged BP, cumulative BP, BP trajectory patterns, and age of hypertension onset.
This review summarises existing research on the association between these indices and hard cardiovascular outcomes, outlines the strengths and weaknesses of these indices, and provides an overview of how longitudinal BP changes can be measured and used to improve cardiovascular disease risk prediction.
Although longitudinal BP indices seem to predict cardiovascular outcomes better than present BP, there are considerable differences in the clinical feasibility of these indices along with a limited number of prospective data.