Cytochrome P450 2E1 Gene Polymorphisms/Haplotypes and Anti-Tuberculosis Drug-Induced Hepatitis in a Chinese Cohort.

Cytochrome P450 2E1 Gene Polymorphisms/Haplotypes and Anti-Tuberculosis Drug-Induced Hepatitis in a Chinese Cohort.

PLoS One. 2013; 8(2): e57526
Tang S, Lv X, Zhang Y, Wu S, Yang Z, Xia Y, Tu D, Deng P, Ma Y, Chen D, Zhan S

The pathogenic mechanism of anti-tuberculosis (anti-TB) drug-induced hepatitis is associated with drug metabolizing enzymes. No tagging single-nucleotide polymorphisms (tSNPs) of cytochrome P450 2E1(CYP2E1) in the risk of anti-TB drug-induced hepatitis have been reported. The present study was aimed at exploring the role of tSNPs in gene in a population-based anti-TB treatment cohort.A nested case-control study was designed. Each hepatitis case was 14 matched with controls by age, gender, treatment history, disease severity and drug dosage. The tSNPs were selected by using Haploview 4.2 based on the HapMap database of Han Chinese in Beijing, and detected by using TaqMan allelic discrimination technology.Eighty-nine anti-TB drug-induced hepatitis cases and 356 controls were included in this study. 6 tSNPs (rs2031920, rs2070672, rs915908, rs8192775, rs2515641, rs2515644) were genotyped and minor allele frequencies of these tSNPs were 21.9%, 23.0%, 19.1%, 23.6%, 20.8% and 44.4% in the cases and 20.9%, 22.7%, 18.9%, 23.2%, 18.2% and 43.2% in the controls, respectively. No significant difference was observed in genotypes or allele frequencies of the 6 tSNPs between case group and control group, and neither of haplotypes in block 1 nor in block 2 was significantly associated with the development of hepatitis.Based on the Chinese anti-TB treatment cohort, we did not find a statistically significant association between genetic polymorphisms of and the risk of anti-TB drug-induced hepatitis. None of the haplotypes showed a significant association with the development of hepatitis in Chinese TB population. HubMed – drug

 

Caveolin-1 Regulates Endothelial Adhesion of Lung Cancer Cells via Reactive Oxygen Species-Dependent Mechanism.

PLoS One. 2013; 8(2): e57466
Chanvorachote P, Chunhacha P

The knowledge regarding the role of caveolin-1 (Cav-1) protein on endothelium adhesion of cancer cells is unclear. The present study revealed that Cav-1 plays a negative regulatory role on cancer-endothelium interaction. Endogenous Cav-1 was shown to down-regulate during cell detachment and the level of such a protein was conversely associated with tumor-endothelial adhesion. Furthermore, the ectopic overexpression of Cav-1 attenuated the ability of the cancer cells to adhere to endothelium while shRNA-mediated Cav-1 knock-down exhibited the opposite effect. We found that cell detachment increased cellular hydrogen peroxide and hydroxyl radical generation and such reactive oxygen species (ROS) were responsible for the increasing interaction between cancer cells and endothelial cells through vascular endothelial cell adhesion molecule-1 (VCAM-1). Importantly, Cav-1 was shown to suppress hydrogen peroxide and hydroxyl radical formation by sustaining the level of activated Akt which was critical for the role of Cav-1 in attenuating the cell adhesion. Together, the present study revealed the novel role of Cav-1 and underlying mechanism on tumor adhesion which explain and highlight an important role of Cav-1 on lung cancer cell metastasis. HubMed – drug

 

Preferential invasion by Plasmodium merozoites and the self-regulation of parasite burden.

PLoS One. 2013; 8(2): e57434
Kerlin DH, Gatton ML

The preferential invasion of particular red blood cell (RBC) age classes may offer a mechanism by which certain species of regulate their population growth. Asexual reproduction of the parasite within RBCs exponentially increases the number of circulating parasites; limiting this explosion in parasite density may be key to providing sufficient time for the parasite to reproduce, and for the host to develop a specific immune response. It is critical that the role of preferential invasion in infection is properly understood to model the within-host dynamics of different species. We develop a simulation model to show that limiting the range of RBC age classes available for invasion is a credible mechanism for restricting parasite density, one which is equally as important as the maximum parasite replication rate and the duration of the erythrocytic cycle. Different species of that regularly infect humans exhibit different preferences for RBC invasion, with all species except appearing to exhibit a combination of characteristics which are able to self-regulate parasite density. HubMed – drug

 

The timing of drug funding announcements relative to elections: a case study involving dementia medications.

PLoS One. 2013; 8(2): e56921
Gill SS, Gupta N, Bell CM, Rochon PA, Austin PC, Laupacis A

Following initial regulatory approval of prescription drugs, many factors may influence insurers and health systems when they decide whether to add these drugs to their formularies. The role of political pressures on drug funding announcements has received relatively little attention, and elections represent an especially powerful form of political pressure. We examined the temporal relationship between decisions to add one class of drugs to publicly funded formularies in Canada’s ten provinces and elections in these jurisdictions.Dates of provincial formulary listings for cholinesterase inhibitors, which are drugs used to treat Alzheimer’s disease and related dementias, were compared to the dates of provincial elections. Medical journal articles, media reports, and proceedings from provincial legislatures were reviewed to assemble information on the chronology of events. We tested whether there was a statistically significant increase in the probability of drug funding announcements within the 60-day intervals preceding provincial elections.Decisions to fund the cholinesterase inhibitors were made over a nine-year span from 1999 to 2007 in the ten provinces. In four of ten provinces, the drugs were added to formularies in a time period closely preceding a provincial election (?=?0.032); funding announcements in these provinces were made between 2 and 47 days prior to elections. Statements made in provincial legislatures highlight the key role of political pressures in these funding announcements.Impending elections appeared to affect the timing of drug funding announcements in this case study. Despite an established structure for evidence-based decision-making, drug funding remains a complex process open to influence from many sources. Awareness of such influences is critical to maintain effective drug policy and public health decision-making. HubMed – drug