T cell-dendritic cell immunological synapses

Dendritic cells (DCs) are myeloid lineage cells that are imprinted by their environment and that mature in response to microbial products. A crucial role of the DC is to impart this context-specific information to T cells as well as to present self and foreign MHC-peptide complexes through formation of an immunological synapse. The structure of the T cell-DC immunological synapse departs from the canonical structure formed with B cells or with supported planar bilayers in that it has multiple foci of T-cell receptor interactions rather than a central focus. Recent studies on model systems provide insight into the mechanisms and biological consequences of the unique T cell-DC synaptic patterns.     

Effect of α-Tocopherol on the Cardiac Antioxidant Defense System and Atherogenic Lipids in Cigarette Smoke-Inhaling Mice

The present study was designed to evaluate the role ofα -tocopherol (AT) on the cardiac antioxidant defense system and atherogenic lipid profile in cigarette smoke (CS)-inhaling mice. CS exposure for 10 wk resulted in an increase in the levels of lipid peroxidation (LPO) and reduction in reduced glutathione (GSH) levels in heart. Supplementation with AT reduced LPO and restored GSH levels to almost those of normals. The activities of the antioxidant enzymes catalase (CAT), glutathione peroxidase (GSH-Px), and glutathione reductase (GR) increased after CS inhalation. However, supplementation with AT resulted in reversing the increase in GSH-Px and GR. The activity of superoxide dismutase (SOD) remained unaltered in all the groups studied. Levels of total cholesterol, low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG) increased, whereas high-density lipoprotein cholesterol (HDL-C) levels decreased in serum following CS inhalation. Supplementation with AT reduced the levels of LDL-C and TG. On the other hand, AT-fed animals showed an increase in HDL-C levels on CS exposure. Based on the results it appears that AT protects the heart from CS-induced peroxidative damage and has antiatherogenic properties.     

Intraoperative floppy iris syndrome in Indian population: A prospective study on incidence,risk factors,and impact on operative performance

Purpose:

The purpose of this study was to evaluate the incidence, risk factors, and impact of intraoperative floppy iris syndrome (IFIS) on surgical performance.

Materials and Methods:

Consecutive cataract surgeries from October 2010 to Feb 2011 (1003 eyes, 980 patients; 568 males, 412 females) were analyzed prospectively. Operating surgeon, masked about medication history, noted the intraoperative details. Cases were identified as IFIS or non-IFIS. Multivariate analysis was performed to find risk factors for IFIS.

Results:

Prevalence of tamsulosin use among men undergoing cataract surgery was 7.0% (41) with incidence of IFIS 4.78% (48). On multivariate analysis, hypertension (OR: 3.2, 95% confidence interval, 95% CI: 1.39-6.57; P = 0.005), use of tamsulosin (OR: 133.32, 95% CI: 50.43-352.48; P < 0.0001), or alfuzosin (OR: 9.36, 95% CI: 2.34-37.50; P = 0.002) were the factors associated with IFIS. Among men taking tamsulosin (n = 41) and alfuzosin (n = 28), 68.3% and 16.6% developed IFIS, respectively. In subgroup analysis of men on tamsulosin, no factor added to the risk posed by tamsulosin. Seventeen of 944 eyes not exposed to any drug had IFIS (0.018%). On subgroup analysis, only risk factor for IFIS was hypertension (OR: 4.67, 95% CI: 1.63-13.35; P = 0.002). Of 48 IFIS eyes, the surgeon observed increased difficulty in 57.1% (21) and additional measures were required in 9 eyes. Mean operative time was increased in IFIS eyes (11.68 ± 3.46 vs. 10.01 ± 0.22 min; P = 0.001). Surgical outcome was good in all cases.

Conclusion:

The prevalence of tamsulosin intake and IFIS incidence is higher in India. Current tamsulosin/alfuzosin use and hypertension are important risk factors. IFIS makes the surgery more difficult, significantly prolongs the operative time, and predisposes for other intraoperative complications. However, with appropriate management, final operative outcome is not affected.     

Renal transplantation in a boy with methylmalonic acidaemia

We present the first reported case of B₁₂ non-responsive methylmalonic acidaemia due to MMAB mutation to undergo an isolated renal transplant for renal failure. At 8 years of age he was listed for a combined liver and kidney transplant following progressive renal impairment. His metabolic control deteriorated with declining renal function and he was commenced on haemodialysis, leading to marked symptomatic and biochemical improvement. He was therefore relisted for isolated cadaveric renal transplant instead. He underwent successful renal transplantation at 12 years of age and now 6 years post transplant he is enjoying a more normal lifestyle with a marked reduction in plasma methylmalonate.     

Vitamin D, parathyroid hormone, and sudden cardiac death: results from the Cardiovascular Health Study

Recent studies have demonstrated greater risks of cardiovascular events and mortality among persons who have lower 25-hydroxyvitamin D (25-OHD) and higher parathyroid hormone (PTH) levels. We sought to evaluate the association between markers of mineral metabolism and sudden cardiac death (SCD) among the 2312 participants from the Cardiovascular Health Study who were free of clinical cardiovascular disease at baseline. We estimated associations of baseline 25-OHD and PTH concentrations individually and in combination with SCD using Cox proportional hazards models after adjustment for demographics, cardiovascular risk factors, and kidney function. During a median follow-up of 14 years, there were 73 adjudicated SCD events. The annual incidence of SCD was greater among subjects who had lower 25-OHD concentrations, 2 events per 1000 for 25-OHD ≥20 ng/mL and 4 events per 1000 for 25-OHD <20 ng/mL. Similarly, SCD incidence was greater among subjects who had higher PTH concentrations, 2 events per 1000 for PTH <65 pg/mL and 4 events per 1000 for PTH ≥65 pg/mL. Multivariate adjustment attenuated associations of 25-OHD and PTH with SCD. Finally, 267 participants (11.7% of the cohort) had high PTH and low 25-OHD concentrations. This combination was associated with a >2-fold risk of SCD after adjustment (hazard ratio: 2.19 [95% CI: 1.17-4.10]; P=0.017) compared with participants with normal levels of PTH and 25-OHD. The combination of lower 25-OHD and higher PTH concentrations appears to be associated independently with SCD risk among older adults without cardiovascular disease.     

Bacopa monnieri prevents colchicine-induced dementia by anti-inflammatory action

Metabolic Brain Disease - Inflammation is considered as an early event in the development of Alzheimer’s disease (AD) that precedes the formation of Aβ plaques and neurofibrillary...