High Content Image Based Analysis Identifies Cell Cycle Inhibitors as Regulators of Ebola Virus Infection

Viruses modulate a number of host biological responses including the cell cycle to favor their replication. In this study, we developed a high-content imaging (HCI) assay to measure DNA content and identify different phases of the cell cycle. We then investigated the potential effects of cell cycle arrest on Ebola virus (EBOV) infection. Cells arrested in G1 phase by serum starvation or G1/S phase using aphidicolin or G2/M phase using nocodazole showed much reduced EBOV infection compared to the untreated control. Release of cells from serum starvation or aphidicolin block resulted in a time-dependent increase in the percentage of EBOV infected cells. The effect of EBOV infection on cell cycle progression was found to be cell-type dependent. Infection of asynchronous MCF-10A cells with EBOV resulted in a reduced number of cells in G2/M phase with concomitant increase of cells in G1 phase. However, these effects were not observed in HeLa or A549 cells. Together, our studies suggest that EBOV requires actively proliferating cells for efficient replication. Furthermore, multiplexing of HCI based assays to detect viral infection, cell cycle status and other phenotypic changes in a single cell population will provide useful information during screening campaigns using siRNA and small molecule therapeutics.     

Aortic root enlargement in patients undergoing double valve replacement for rheumatic etiology–preliminary results

Introduction  

Combined aortic and mitral valve disease is usually of rheumatic origin. In these patients we often encounter problem of small valve annuli particularly with aortic annulus. It is still debated whether a small prosthesis should be used or aortic root should be enlarged to prevent Patient Prosthesis Mismatch (PPM). This study was undertaken to review our strategy and feasibility of Aortic Root Enlargement (ARE) in patient undergo Double Valve Replacement (DVR) to avoid mismatch without increase in cost of treatment, morbidity or mortality.     

Mumbai disease in far western Nepal: HIV infection and syphilis among male migrant-returnees and non-migrants

OBJECTIVE: To measure the seroprevalence of human immunodeficiency virus (HIV) infection and syphilis, and to assess the behavioural risk factors for these infections among migrant-returnees and non-migrants in far western Nepal. METHODS: In April 2001, we recruited 97 male migrant-returnees and 40 non-migrants from five rural villages in Doti district where migration to Mumbai is common. For data collection, we conducted a serological examination for HIV and syphilis, and a perception and behaviour survey on HIV and other sexually transmitted infections. RESULTS: We found that 11 of 137 men (8%) were positive for HIV infection and 30 men (22%) for syphilis. The respondents, especially the migrant-returnees from Mumbai, were engaging in risky behaviours such as pre- or extramarital sex, and sex with multiple partners, including sex workers. CONCLUSIONS: This study revealed high HIV and syphilis prevalence among the male migrant-returnees and non-migrants in far western Nepal where migration to Mumbai is common. The prevalent behaviours, particularly among the migrant-returnees, imply urgent needs of the behavioural modification programme in this area to prevent the spread of HIV infection to general population.     

Investigations of cardiac sarcolemmal ATPase activity in rabbits with acute myocarditis produced by scorpion venom (Buthus tamulus)

Acute myocarditis is produced in rabbits with scorpion (Buthus tamulus) (a common scorpion found in South India) venom. Acute myocarditis is confirmed by changes in the ECG taken before and after venom injection. The atrial and ventricular sarcolemmal Na+-K+ ATPase, Mg++ ATPase, and Ca++ ATPase activities are assayed in control and venom injected rabbits. Atrial and ventricular sarcolemmal ATPase activities are similar in control animals. A significant reduction in atrial Ca++ ATPase activity is seen in venom treated rabbits. Animals injected with 2 mg/Kg venom exhibited significant increases in Mg++ ATPase and Ca++ ATPase activities in the ventricular sarcolemma. However, significant reductions in Na+-K+ ATPase and Ca++ ATPase activities are observed in ventricular tissue from rabbits treated with 4 mg/Kg of venom.     

The metabolic syndrome: peroxisome proliferator-activated receptor gamma and its therapeutic modulation

By the end of this decade, it has been estimated that between 200 million and 300 million people worldwide will meet World Health Organization diagnostic criteria for diabetes mellitus. This epidemic of predominantly type 2 diabetes has largely been mediated by our shift toward a more sedentary lifestyle predisposing to obesity and insulin resistance. Affected individuals can also exhibit an array of associated undesirable traits such as hypertension, dyslipidemia, and hypercoagulability, leading to morbidity and mortality from atherosclerotic vascular disease. The coexistence of several of these traits with insulin resistance constitutes the metabolic syndrome. Accordingly, improving insulin sensitivity in this group, and thereby potentially ameliorating the excess vascular risk, is a primary goal of treatment. Recent interest has focused on the thiazolidinediones, a novel class of antidiabetic agents, which act as insulin sensitizers and, therefore, potentially target the underlying metabolic disturbance. These agents are high-affinity ligands for the nuclear receptor peroxisome proliferator-activated receptor gamma, and a large body of in vitro and in vivo data has evolved to support their increasing clinical use. Importantly, clinical and laboratory findings in human subjects harboring natural mutations and polymorphisms within the receptor have provided additional insights. Here, we focus on the consequences of inherited variation in the human peroxisome proliferator-activated receptor gamma gene, linking this receptor to disordered glucose homeostasis, adipogenesis, lipid metabolism, and blood pressure regulation. These studies provide further support for the future development of more selective receptor modulators, targeting specific pathways to ameliorate facets of the metabolic syndrome.     

How good is endoscopic ultrasound for TNM staging of gastric cancers？ A meta-analysis and systematic review

AIM： To evaluate the accuracy of endoscopic ultrasound （EUS） for staging of gastric cancers.
METHODS： Only EUS studies confirmed by surgery were selected. Only studies from which a 2×2 table could be constructed for true positive, false negative, false positive and true negative values were included. Articles were searched in Medline, Pubmed, Ovid journals, Cumulative index for nursing ＆ allied health literature, International pharmaceutical abstracts, old Medline, Medline nonindexed citations, and Cochrane control trial registry. Two reviewers independently searched and extracted data. The differences were resolved by mutual agreement. 2×2 tables were constructed with the data extracted from each study. Meta-analysis for the accuracy of EUS was analyzed by calculating pooled estimates of sensitivity, specificity, likelihood ratios, and diagnostic odds ratio. Pooling was conducted by both the Mantel-Haenszel method （fixed effects model） and DerSimonian Laird method （random effects model）. The heterogeneity of studies was tested using Cochran＇s Q test based upon inverse variance weights.
RESULTS： Initial search identified 1620 reference articles and of these, 376 relevant articles were selected and reviewed. Twenty-two studies （n = 1896） which met the inclusion criteria were included in this analysis. Pooled sensitivity of T1 was 88.1% （95% CI： 84.5-91.1） and T2 was 82.3% （95% CI： 78.2-86.0）. For T3, pooled sensitivity was 89.7% （95% CI： 87.1-92.0）. T4 had a pooled sensitivity of 99.2% （95% CI： 97.1-99.9）. For nodal staging, the pooled sensitivity for N1 was 58.2% （95% CI： 53.5-62.8） and N2 was 64.9% （95% CI： 60.8-68.8）. Pooled sensitivity to diagnose distant metastasis was 73.2% （95% CI： 63.2-81.7）. The P for chi-squared heterogeneity for all the pooled accuracy estimates was 〉0. 10.
CONCLUSION： EUS results are more accurate with advanced disease than early disease. If EUS diagnoses advanced disease, such as T4 disease, the patient is     

Redo mitral valve surgery using the port-access system

Redo mitral valve surgery is hazardous, hence we explored an alternative approach using a port-access system that avoids reentry. Between October 1997 and December 2000, 32 patients underwent mitral reoperation using the system. All patients had previous cardiac operations. This procedure consisted of a right anterolateral minithoracotomy and femorofemoral cannulation using special port-access instruments and endoaortic clamping in 24 patients or direct transthoracic sliding-rod aortic clamping in 8. The valve disease was of rheumatic etiology in 28 patients and degenerative in 4. The valve was replaced in 31 cases and a paravalvular leak after mitral valve replacement was closed in 1. In 2 cases, the tricuspid valve was repaired along with mitral valve replacement. Mean total operating time was 4.5 +/- 1.2 hours, cardiopulmonary bypass time 162 +/- 72 minutes, and aortic crossclamp time 62 +/- 21 minutes. There was no mortality, and mean stay in the intensive care unit was 22 +/- 7 hours and hospital stay 6.4 +/- 1.2 days. Postoperative blood transfusion was required in 12 patients. In view of the favorable results, we recommend using the port-access system as a standard approach for mitral reoperation.