Novelty exposure overcomes foot shock-induced spatial-memory impairment by processes of synaptic-tagging in rats

Novelty processing can transform short-term into long-term memory. We propose that this memory-reinforcing effect of novelty could be explained by mechanisms outlined in the "synaptic tagging hypothesis." Initial short-term memory is sustained by a transient plasticity change at activated synapses and sets synaptic tags. These tags are later able to capture and process the plasticity-related proteins (PRPs), which are required to transform a short-term synaptic change into a long-term one. Novelty is involved in inducing the synthesis of PRPs [Moncada D, et al. (2011) Proc Natl Acad Sci USA 108:12937-12936], which are then captured by the tagged synapses, consolidating memory. In contrast to novelty, stress can impair learning, memory, and synaptic plasticity. Here, we address questions as to whether novelty-induced PRPs are able to prevent the loss of memory caused by stress and if the latter would not interact with the tag-setting process. We used water-maze (WM) training as a spatial learning paradigm to test our hypothesis. Stress was induced by a strong foot shock (FS; 5 × 1 mA, 2 s) applied 5 min after WM training. Our data show that FS reduced long-term but not short-term memory in the WM paradigm. This negative effect on memory consolidation was time- and training-dependent. Interestingly, novelty exposure prevented the stress-induced memory loss of the spatial task and increased BDNF and Arc expression. This rescuing effect was blocked by anisomycin, suggesting that WM-tagged synapses were not reset by FS and were thus able to capture the novelty-induced PRPs, re-establishing FS-impaired long-term memory.     

American indians with substance use disorders: treatment needs and comorbid conditions

Background: American Indians and Alaska Natives (AI/ANs) experience significant disparities in health status and access to care. Furthermore, only limited data are available on substance use, mental health disorders, and treatment needs for this population. Addressing such disparities and developing culturally relevant, effective interventions for AI/AN communities require participatory research. Objectives and Methods: The Western States Node of the National Institute on Drug Abuse Clinical Trials Network partnered with two American Indian substance abuse treatment programs: an urban health center and a reservation-based program to assess client characteristics, drug use patterns, and treatment needs. Data collected by staff members at the respective programs from urban (n = 74) and reservation (n = 121) clients were compared. Additional sub-analysis examined patients reporting regular opioid use and mood disorders. Results: Findings indicate that urban clients were more likely to report employment problems, polysubstance use, and a history of abuse. Reservation-based clients reported having more severe medical problems and a greater prevalence of psychiatric problems. Clients who were regular opioid users were more likely to report having a chronic medical condition, suicidal thoughts, suicide attempts, polysubstance abuse, and IV drug use. Clients who reported a history of depression had twice as many lifetime hospitalizations and more than five times as many days with medical problems. Conclusions: Findings from this project provide information about the patterns of substance abuse and the importance of comprehensive assessments of trauma and comorbid conditions. Results point to the need for integrative coordinated care and auxiliary services for AI/AN clients seeking treatment for substance use disorders.     

Staphylococcus aureus infections after liver transplantation

Background

More data on the risk factors and outcomes after Staphylococcus aureus infections in liver transplantation are needed.

Methods

Liver recipients with S. aureus infections (cases) were retrospectively identified and compared to gender-, age-, and transplant type-matched (1:2) non-S. aureus-infected controls. Risk factors associated with S. aureus infections were identified by conditional logistic regression analysis.

Results

We evaluated 51 patients (median age 52?years). First S. aureus infections developed at a median time of 29?days after transplantation, with 52.94% of them in the first month; 88.24% were nosocomial, 41.18% were polymicrobial, and 47.06% were caused by methicillin-resistant S. aureus (MRSA). Surgical site infections represented 58.82% and bacteremia 23.53%. By univariate analysis, patients with S. aureus infections were intubated more frequently (odds ratio [OR] 26.92, 95% confidence interval [CI] 3.23?C3,504.15, p?=?0.0006), had a central line (OR 11.69, 95% CI 1.42?C95.9, p?=?0.02), or recent surgery (OR 26.92, 95% CI 3.23?C3,504.15, p?=?0.0006) compared with controls. By multivariate analysis, subjects who underwent surgery within 2?weeks prior to infection had a 26.9 times higher risk of developing S. aureus infection (95% CI 3.23?C3,504.15, p?=?0.0006); these results were adjusted for matched criteria. S. aureus infections did not affect graft or patient survival, but the study was not powered for such outcomes.

Conclusion

Only recent surgical procedure was found to be a significant independent risk factor for S. aureus infections after liver transplantation.     

Sex dependent influence of a functional polymorphism in steroid 5‐α‐reductase type 2 (SRD5A2) on post‐traumatic stress symptoms

A non‐synonymous, single nucleotide polymorphism (SNP) in the gene coding for steroid 5‐α‐reductase type 2 (SRD5A2) is associated with reduced conversion of testosterone to dihydrotestosterone (DHT). Because SRD5A2 participates in the regulation of testosterone and cortisol metabolism, hormones shown to be dysregulated in patients with PTSD, we examined whether the V89L variant (rs523349) influences risk for post‐traumatic stress disorder (PTSD). Study participants (N = 1,443) were traumatized African‐American patients of low socioeconomic status with high rates of lifetime trauma exposure recruited from the primary care clinics of a large, urban hospital. PTSD symptoms were measured with the post‐traumatic stress symptom scale (PSS). Subjects were genotyped for the V89L variant (rs523349) of SRD5A2. We initially found a significant sex‐dependent effect of genotype in male but not female subjects on symptoms. Associations with PTSD symptoms were confirmed using a separate internal replication sample with identical methods of data analysis, followed by pooled analysis of the combined samples (N = 1,443, sex × genotype interaction P < 0.002; males: n = 536, P < 0.001). These data support the hypothesis that functional variation within SRD5A2 influences, in a sex‐specific way, the severity of post‐traumatic stress symptoms and risk for diagnosis of PTSD. © 2013 Wiley Periodicals, Inc.     

Reduction in length of stay for patients undergoing oesophageal and gastric resections with implementation of enhanced recovery packages

Introduction

The high mortality and morbidity associated with resection for oesophagogastric malignancy has resulted in a conservative approach to the postoperative management of this patient group. In August 2009 we introduced an enhanced recovery after surgery (ERAS) pathway tailored to patients undergoing resection for oesophagogastric malignancy. We aimed to assess the impact of this change in practice on standard clinical outcomes.

Methods

Two cohorts were studied of patients undergoing resection for oesophagogastric malignancy before (August 2008 – July 2009) and after (August 2009 – July 2010) the implementation of the ERAS pathway. Data were collected on demographics, interventions, length of stay, morbidity and in-hospital mortality.

Results

There were 53 and 55 oesophagogastric resections undertaken respectively for malignant disease in each of the study periods. The median length of stay for both gastric and oesophageal resection decreased from 15 to 11 days (Mann– Whitney U, p<0.001) following implementation of the ERAS pathway. There was no significant increase in morbidity (gastric resection 23.1% vs 5.3% and oesophageal resection 25.9% vs 16.7%) or mortality (gastric resection no deaths and oesophageal resection 1.8% vs 3.6%) associated with the changes. There was a significant decrease in the number of oral contrast studies used following oesophageal resection, with a reduction from 21 (77.8%) in 2008–2009 to 6 (16.7%) in 2009–2010 (chi-squared test, p<0.0001).

Conclusions

The introduction of an enhanced recovery programme following oesophagogastric surgery resulted in a significant decrease in length of median patient stay in hospital without a significant increase in associated morbidity and mortality.     

Computer-based interventions for sexual health promotion: systematic review and meta-analyses

This systematic review was conducted to determine the effects of self-help interactive computer-based interventions (ICBIs) for sexual health promotion. We searched 40 databases for randomized controlled trials (RCTs) of computer-based interventions, defining 'interactive' as programmes that require contributions from users to produce personally relevant material. We conducted searches and analysed data using Cochrane Collaboration methods. Results of RCTs were pooled using a random-effects model with standardized mean differences for continuous outcomes and odds ratios (ORs) for binary outcomes, with heterogeneity assessed using the I(2) statistic. We identified 15 RCTs of ICBIs (3917 participants). Comparing ICBIs to minimal interventions, there were significant effects on sexual health knowledge (standardized mean difference [SMD] 0.72, 95% confidence interval [CI] 0.27-1.18); safer sex self-efficacy (SMD 0.17, 95% CI 0.05-0.29); safer-sex intentions (SMD 0.16, 95% CI 0.02-0.30); and sexual behaviour (OR 1.75, 95% CI 1.18-2.59). ICBIs had a greater impact on sexual health knowledge than face-to-face interventions did (SMD 0.36, 95% CI 0.13-0.58). ICBIs are effective tools for learning about sexual health, and show promising effects on self-efficacy, intention and sexual behaviour. More data are needed to analyse biological outcomes and cost-effectiveness.