Prediction of Learned Resistance or Helplessness by Hippocampal-Prefrontal Cortical Network Activity during Stress

The perception of control over a stressful experience may determine its impacts and generate resistance against future stressors. Although the medial prefrontal cortex (PFC) and the hippocampus (HPC) are implicated in the encoding of stressor controllability, the neural dynamics underlying this process are unknown. Here, we recorded HPC and PFC neural activities in male rats during the exposure to controllable, uncontrollable, or no shocks and investigated electrophysiological predictors of escape performance upon exposure to subsequent uncontrollable shocks. We were able to accurately discriminate stressed from nonstressed animals and predict resistant (R) or helpless (H) individuals based on hippocampal-cortical oscillatory dynamics. Remarkably, R animals exhibited an increase in theta power during CS, while H exhibited a decrease. Furthermore, R exhibited higher HPC to PFC θ synchronization during stress. Notably, HPC-PFC θ connectivity in the initial stress exposure showed strong correlations with escape performance evaluated days later. R rats also showed stronger θ coupling to both γ oscillations and neuronal firing in the PFC. Finally, we found that these distinct features of network dynamics collectively formed a pattern that accurately predicted learned resistance and was lacking in H individuals. Our findings suggest that hippocampal-prefrontal network θ activity supports cognitive mechanisms of stress coping, whose impairment may underlie vulnerability to stress-related disorders.SIGNIFICANCE STATEMENT The appraisal of adversities as controllable or uncontrollable is key in determining resilience or risk for stress-related disorders. Here, we performed the first electrophysiological investigation during controllable or uncontrollable stress. Pharmacological studies showed that the prefrontal cortex (PFC) and the hippocampus (HPC) encode stressor controllability, and here we identified the neural activity underlying this process. This “neural signature of stressor controllability” accurately predicted resistance to future stressors and was characterized by increased HPC-PFC oscillatory activity in the θ frequency (4–10 Hz). Our findings suggest a new role of frontal θ oscillations in adaptive stress coping, integrating its emotional and cognitive functions. We also endorse the potential of this biomarker to guide neurophysiologically-informed and rhythm-based stimulation therapies for depression.     

The anatomical and radiological evaluation of the Vidian canal on cone-beam computed tomography images

European Archives of Oto-Rhino-Laryngology - The aim of this study is to explore the anatomy of the Vidian nerve to elucidate the appropriate surgical approach based on preoperative cone-beam...     

Quantitative Assessment of Anti-Gravity Reflexes to Evaluate Vestibular Dysfunction in Rats

Journal of the Association for Research in Otolaryngology - The tail-lift reflex and the air-righting reflex are anti-gravity reflexes in rats that depend on vestibular function. To obtain...     

Sonication did not provide reliability to Maki technique for catheter related bloodstream infection diagnosis

ObjectiveThe aim of our study was to analyze sonication and Maki techniques for diagnosis of catheter tip colonization and catheter-related bloodstream infection (CRBSI) on patients admitted to ICU.Material and methodsObservational and prospective study in one Intensive Care Unit. Patients with some central venous catheter (CVC) at least for 7 days and catheter-related infection (CRI) suspicion (new episode of fever or sepsis) were included. We performed Maki technique followed by sonication of catheter tip. We compared area under the curve (AUC) of Maki, sonication, and techniques combination to diagnosis catheter tip colonization and CRBSI.ResultsWe included 94 CVC from 87 CRI suspicion episodes. We found 14 cases of catheter tip colonization and 10 cases of CRBSI. Of the 14 catheter tip colonization cases, 7 (50.0%) were detected by Maki and sonication techniques, 6 (42.9%) were detected only by Maki technique, and 1 (7.1%) was detected only by sonication technique. Of the 10 CRBSI, 6 (60.0%) were detected by Maki and sonication techniques, 4 (40.0%) were detected only by Maki technique, and any only by sonication technique. We found higher AUC in Maki technique than in sonication technique to diagnosis of CRBSI (p=0.02) and to diagnosis of catheter tip colonization (p=0.03). No significant differences were found in AUC between Maki technique and combination techniques for diagnosis of catheter tip colonization (p=0.32) and of CRBSI (p=0.32).Conclusion.:Sonication did not provide reliability to Maki technique for diagnosis of catheter tip colonization and CRBSI.     

Epidemiological Review of Spinal Cord Injury due to Road Traffic Accidents in Latin America

Spinal cord injury (SCI) is a disease that affects the normal function of the spinal cord. Road traffic accidents (RTAs) represent the main cause of SCI worldwide. SCI may generate physical disability and economic dependency, which is especially significant in low- and middle-income countries such as most of the Latin American countries. The main objective of this study was to present an epidemiological review of SCI secondary to RTAs. Stronger evidence on this condition in Latin America is important for future-specific data collection and prevention strategies. A literature review was carried out using specific search strategies in databases of indexed journals from the period 2000 to 2019. Data on SCI secondary to RTAs in the Latin American region were collected and analyzed. After initial screening and removal of duplicates, 16 articles met the inclusion criteria and were chosen for analysis. Data from 7 Latin American countries were retrievable. On average, RTAs were responsible for 40.81% of SCI. Data from different studies are heterogeneous. Car accidents and moto accidents were equally responsible for SCIs (50.61% vs. 49.06%). The thoracic segments were the most commonly affected (57.87%). Males in their 30s were the most affected category (76.6%). SCI due to RTAs may represent a severe but preventable condition that affects mostly men in their productive age, generating important social and economic issues. Data about this condition in Latin America are scarce, and could limit prevention and treatment strategies. Prospective data collection about this condition is recommended.     

Zinc Deficiency Interacts with Intestinal/Urogenital Parasites in the Pathway to Anemia in Preschool Children,Bengo–Angola

In host organisms with normal micronutrient status, nutritional immunity is a strongly regulated response aiming at decreasing the progression and severity of infections. Zinc deficiency may disturb this balance, impairing immune responses to infections, which may indirectly increase infection-related anemia. Since zinc deficiency may associate directly with anemia, the role of infections is often overlooked. Herein, we investigated the participation of infections (or inflammation) in the causal pathway between zinc deficiency and anemia. This transversal study, conducted in 2015 in Bengo-Angola, enrolled 852 under-3-year-old children. Logistic regression models were used to investigate interaction and mediation effects, and significance was confirmed by the Sobel test. In sum, 6.8% of children had zinc deficiency, 45.9% had anemia, and 15.6% had at least one intestinal/urogenital parasite. Furthermore, we found (1) no evidence that inflammation mediates or interacts with zinc deficiency to cause anemia, and (2) zinc deficiency interacts with infections, significantly increasing the odds of anemia (OR: 13.26, p = 0.022). This interaction was stronger among children with iron deficiency anemia (OR: 46.66, p = 0.003). Our results suggest that zinc deficiency may impair the immune response to infections and/or that intestinal parasites could have developed mechanisms to avoid zinc-limited environments. Further studies are needed to corroborate these suggestions.     

Benzodiazepine and Z-Drug Use and the Risk of Developing Dementia

BackgroundBenzodiazepines (BZDs) and Z-drugs (BZDRs) are among the most prescribed medications for anxiety and insomnia, especially among older adults. Our objective was to investigate the association between the use of BZDRs and the risk of dementia.MethodsA community-based retrospective cohort study was conducted based on the data available from 2002 to 2015 in Catalan Health Service. This cohort included all BZDR users (N = 83 138) and nonusers (N = 84 652) older than 45 years. A minimum 5-year lag window and an adjustment for psychiatric problems were applied for the data analysis.ResultsThe hazard ratio (HR) for the risk of incident dementia among BZDR users was 1.22 (95% CI = 1.15 to 1.31). This risk was not significant after adjusting the data confounding factors (HR = 1.01; 95% CI = 0.94 to 1.08). We observed a higher risk with short-to-intermediate half-life BZDs (HR = 1.11; 95% CI = 1.04 to 1.20) and Z-drugs (HR = 1.20; 95% CI = 1.07 to 1.33) than for intermediate-to-long half-life BZDs (HR = 1.01; 95% CI = 0.94 to 1.08). We demonstrated a higher risk of incident dementia (HR = 1.23; 95% CI = 1.07 to 1.41 and odds ratio = 1.38; 95% CI = 1.27 to 1.50, respectively) in patients who received 91 to 180 defined daily doses (DDDs) and >180 DDDs compared with patients who received <90 DDD. Regarding patient sex, the risk of dementia was higher in women than in men.ConclusionWe found that the incidence of dementia was not higher among all BZDR users. Short half-life BZDs and Z-drugs increased the risk of dementia at the highest doses, especially in female patients, showing a dose-response relationship.     

Design and characterization of a biodegradable double‐layer scaffold aimed at periodontal tissue‐engineering applications

The inefficacy of the currently used therapies in achieving the regeneration ad integrum of the periodontium stimulates the search for alternative approaches, such as tissue‐engineering strategies. Therefore, the core objective of this study was to develop a biodegradable double‐layer scaffold for periodontal tissue engineering. The design philosophy was based on a double‐layered construct obtained from a blend of starch and poly‐ε‐caprolactone (30:70 wt%; SPCL). A SPCL fibre mesh functionalized with silanol groups to promote osteogenesis was combined with a SPCL solvent casting membrane aiming at acting as a barrier against the migration of gingival epithelium into the periodontal defect. Each layer of the double‐layer scaffolds was characterized in terms of morphology, surface chemical composition, degradation behaviour and mechanical properties. Moreover, the behaviour of seeded/cultured canine adipose‐derived stem cells (cASCs) was assessed. In general, the developed double‐layered scaffolds demonstrated adequate degradation and mechanical behaviour for the target application. Furthermore, the biological assays revealed that both layers of the scaffold allow adhesion and proliferation of the seeded undifferentiated cASCs, and the incorporation of silanol groups into the fibre‐mesh layer enhance the expression of a typical osteogenic marker. This study allowed an innovative construct to be developed, combining a three‐dimensional (3D) scaffold with osteoconductive properties and with potential to assist periodontal regeneration, carrying new possible solutions to current clinical needs. Copyright © 2013 John Wiley & Sons, Ltd.