Chronic brain stimulation rewarding experience ameliorates depression-induced cognitive deficits and restores aberrant plasticity in the prefrontal cortex

Background

Major depressive disorder (MDD) is a multifactorial disease which often coexists with cognitive deficits. Depression-induced cognitive deficits are known to be associated with aberrant reward processing, neurochemical and structural alterations. Recent studies have shown that chronic electrical stimulation of brain reward areas induces a robust antidepressant effect. However, the effects of repeated electrical self-stimulation of lateral hypothalamus - medial forebrain bundle (LH-MFB) on depression-induced cognitive deficits and associated neurochemical and structural alterations in the prefrontal cortex (PFC) are unknown.

Pharmacokinetic/pharmacodynamic profiling of imipenem in patients admitted to an intensive care unit in India: A nonrandomized,cross-sectional,analytical, open-labeled study

Results:The difference in the plasma imipenem concentration between the gastrointestinal and the nongastrointestinal groups was significant at 2 h (P = 0.015) following drug dosing; while the difference was significant between the skin/cellulitis and nonskin/cellulitus groups at 2 h (P = 0.008), after drug dosing. The imipenem levels were above the MIC and 5 times the MIC for the isolated organism in 96.67% and 50% of the patients, respectively.Conclusions:The pharmacokinetic profile of imipenem does not vary according to the locus of an infection in critically ill patients. Imipenem, 3 g/day intermittent dosing, maintains a plasma concentration which is adequate to treat most infections encountered in patients admitted to an ICU. However, a change in the dosing regimen is suggested for patients infected with organisms having MIC values above 4 mg/L.     

Factors Associated With the Occurrence and Treatment of Supraventricular Tachycardia in a Pediatric Congenital Heart Disease Cohort

In patients with congenital heart disease (CHD), the association between supraventricular tachycardia (SVT), type of pathophysiology, and therapeutic interventions in a population-based cohort warrants further examination. A retrospective, longitudinal 15-year data set (1996–2010) was analyzed. Inclusion criteria included age ≤17 years, enrolled in South Carolina State Medicaid, and diagnosed as having one or more CHDs as well as SVT. SVT was diagnosed in 6.5 % of CHD patients (N = 1,169) during the 15-year epoch investigated. SVT was less likely to occur in African-American (hazard ratio [HR] = 0.76) or male patients (HR = 0.88), but it was significantly more likely to occur in patients age ≤12 months or in adolescents ≥13 years in those undergoing multiple surgeries/medical interventions for their CHD (HR = 1.14), those receiving antiarrhythmic/diuretic/preload-/afterload-reducing medications (HR = 5.46), and those with severe/cyanotic CHDs (HR = 1.52) or chromosomal abnormalities (HR = 1.64). Children who had an atrial septal defect secundum (adjusted odds ratio [aOR] = 3.03) and those treated with diuretic or antiarrhythmic medication (aOR = 1.80) were significantly more likely to undergo SVT ablation, whereas those with late-onset pulmonary hypertension (ages 6–12 years old) were significantly less likely to undergo SVT ablation. SVT recurred in only 14 of 166 patients who underwent SVT ablation. Multiple medical interventions at an early age may increase the risk of SVT occurrence in young CHD patients regardless of the severity/complexity of the CHD.     

An optimal control model for cloud seeding in a deterministic and stochastic environment

To promote artificial rain in India and other such developing countries, in this article, we have proposed and analyzed a nonlinear mathematical model for cloud seeding by considering that aerosols are introduced proportional to the density of water vapors present in the atmosphere. The model is analyzed using Lyapunov's stability theory of differential equations. To reduce the cost of cloud seeding, an optimal control strategy is designed by incorporating four control parameters. We have shown the existence and uniqueness of solution of this optimal control problem, using Pontryagins Maximum Principle. To minimize the cost in making artificial rain, the optimal control problem provides the strategy for the rate of introduction of aerosols in the atmosphere. To capture the effects of environmental noise on control strategies, the model in deterministic framework is converted into stochastic framework. In this regard, the Hamilton-Jacobi-Bellman equation for stochastic control cost function has been formed. The stochastic analysis implies that the control strategy is effective in reducing the cost and increasing rainfall.