Selective Ablation of BDNF from Microglia Reveals Novel Roles in Self-Renewal and Hippocampal Neurogenesis

Microglia, the resident immune cells of the CNS, have emerged as key regulators of neural precursor cell activity in the adult brain. However, the microglia-derived factors that mediate these effects remain largely unknown. In the present study, we investigated a role for microglial brain-derived neurotrophic factor (BDNF), a neurotrophic factor with well known effects on neuronal survival and plasticity. Surprisingly, we found that selective genetic ablation of BDNF from microglia increased the production of newborn neurons under both physiological and inflammatory conditions (e.g., LPS-induced infection and traumatic brain injury). Genetic ablation of BDNF from microglia otherwise also interfered with self-renewal/proliferation, reducing their overall density. In conclusion, we identify microglial BDNF as an important factor regulating microglia population dynamics and states, which in turn influences neurogenesis under both homeostatic and pathologic conditions.SIGNIFICANCE STATEMENT (1) Microglial BDNF contributes to self-renewal and density of microglia in the brain. (2) Selective ablation of BDNF in microglia stimulates neural precursor proliferation. (3) Loss of microglial BDNF augments working memory following traumatic brain injury. (4) Benefits of repopulating microglia on brain injury are not mediated via microglial BDNF.     

Interaction of the hepatitis C virus (HCV) core with cellular genes in the development of HCV-induced steatosis

Hepatitis C virus (HCV) has chronically infected a large number of patients, leading to the development of steatosis, cirrhosis and, ultimately, hepatocellular carcinoma. The pathogenesis of HCV has not been fully explained, although steatosis is considered to contribute greatly to liver fibrosis progression, modulating host-cell lipid metabolism. Suspected underlying molecular mechanisms include interactions between HCV proteins and intracellular lipid metabolic pathways. Recent studies have suggested that the nucleocapsid of HCV (core) acts as a pathogenic factor involved in lipid droplet accumulation, changes in lipogenic gene expression and/or the activity of lipogenic proteins in a genotype-specific manner. In this review, we have tried to summarize the current knowledge regarding HCV-induced steatosis and the regulation of expression of host genes and receptors that aid in the viral life cycle and promote liver diseases.     

Screening of antenatal depression in Pakistan: risk factors and effects on obstetric and neonatal outcomes

Introduction: To determine the frequency of probable antenatal depression (AD) in pregnant women in third trimester, assess the risk factors and its impact on obstetric and neonatal outcomes in a developing country. Methods: A prospective study conducted in a tertiary care hospital in Lahore from March 2007 to July 2007. Two hundred and thirteen pregnant women in the third trimester, attending the Gynecology Outpatient Clinic were recruited. They were assessed by a semistructured questionnaire to gather demographic details and various risk factors for AD. AD was assessed by Edinburgh Postnatal Depression Scale. All women were followed until delivery to determine their obstetric and neonatal outcomes. Results: Out of 213 women, 91 (42.7%) scored above the cut‐off for AD. More women with depression reported problems in their marriage, problems with parents/in laws, history of domestic violence, past history of psychiatric problems and history of postnatal depression. In the obstetric risk factors history of previous miscarriages, stillbirths, and complications in previous pregnancy reached statistical significance. Thirty‐seven (17.3%) women were lost to follow up. Women with AD had more obstetric complications during delivery. Babies of mothers with AD had significantly low birth weight, as well as low mean APGAR scores at 1 and 5 minutes following birth. Discussion: AD is a common problem in Pakistani Society. In view of the risk factors and adverse outcomes associated with depression during pregnancy, there is need for close liaison between Gynaecologists and Psychiatrists in managing these patients.     

Assessment of Trace Metal and Metalloid Accumulation and Human Health Risk from Vegetables Consumption through Spinach and Coriander Specimens Irrigated with Wastewater

This study focused on evaluating the metal and metalloid contamination and associated risks in the two vegetables crops, coriander (Coriandrum sativum) and spinach (Spinacia oleracea) treated with three water regimes, canal water, groundwater and municipal wastewater. These vegetables are widely consumed by people and are also used in traditional medicine for treating various disorders. Metal and metalloid accumulation (Zn, Pb, Se, Cu, As, Mo, Fe, Ni) was found higher in vegetables treated with wastewater. Wastewater treated soil had high pollution load index. Fe, Zn, As and Pb had higher values in water, soil and vegetables as compared to other studied metals. Overall, metal correlation for soil and vegetables was significant and positive except for Fe and Cu in spinach. The highest value for daily metal intake was estimated for Fe while Se had the lowest value for the same index. It was thus concluded that trace metal and metalloid accumulation was a major health concern for the public consuming these vegetables.     

Correlation and prediction of a large blood-brain distribution data set--an LFER study.

We report linear free energy relation (LFER) models of the equilibrium distribution of molecules between blood and brain, as log BB values. This method relates log BB values to fundamental molecular properties, such as hydrogen bonding capability, polarity/polarisability and size. Our best model of this form covers 148 compounds, the largest set of log BB data yet used in such a model, resulting in R(2)=0.745 and e.s.d.=0.343 after inclusion of an indicator variable for carboxylic acids. This represents rather better accuracy than a number of previously reported models based on subsets of our data. The model also reveals the factors that affect log BB: molecular size and dispersion effects increase brain uptake, while polarity/polarisability and hydrogen-bond acidity and basicity decrease it. By splitting the full data set into several randomly selected training and test sets, we conclude that such a model can predict log BB values with an accuracy of less than 0.35 log units. The method is very rapid-log BB can be calculated from structure at a rate of 700 molecules per minute on a silicon graphics O(2).     

Takayasu arteritis of subclavian artery in a Caucasian

Takayasu arteritis, an inflammatory and obliterative disease of medium and large arteries, is classified as a giant cell arteritis. It has a predilection for the aortic arch, its main branches, and coronary and pulmonary arteries. The early symptoms of Takayasu arteritis may be mainly systemic and may resemble polymyalgia rheumatica. The etiology is unknown but autoimmunity has been suggested to play a role. Diagnosis is based on symptoms, physical findings, and imaging, because tissue diagnosis is rarely feasible. Unlike atherosclerotic vascular disease, Takayasu arteritis affects primarily, but not exclusively, young women. Contrary to earlier reports, it is not limited to the women of Japanese origin but is present worldwide. The current report is of a Caucasian woman who presented with nonspecific complaints of upper back pain, weakness, malaise, and fatigue. Her physical examination revealed absent left radial pulse and a blood pressure differential, later confirmed by radiological imaging studies to be due to left subclavian artery stenosis consistent with Takayasu arteritis. The presentation and management of the patient is described, and Takayasu arteritis is succinctly reviewed.     

Dual behavior of HCV Core gene in regulation of apoptosis is important in progression of HCC

Hepatitis C virus (HCV) causes acute and chronic hepatitis which can lead to HCC (Hepatocelluar carcinoma) via oxidative stress, steatosis, insulin resistance, fibrosis and liver cirrhosis. Apoptosis is essential for the control and eradication of viral infections. In acute HCV infection, enhanced hepatocyte apoptosis is significant for elimination of viral pathogen. In case of chronic HCV, down regulation of apoptosis and enhanced cell proliferation not only causes HCV infection persistency in the majority of patients. However, the impact of apoptosis in chronic HCV infection is not well understood. It may be harmful by triggering liver fibrosis, or essential in interferon (IFN) induced HCV elimination. Regulation of apoptosis in hepatocytes by HCV Core is so important in progression of HCC. This review focuses on the dual character of HCV Core on regulation of apoptosis and progression of HCC.