Hepatitis B and C Virus Infections Among Human Immunodeficiency Virus-Infected People Who Inject Drugs in Lahore, Pakistan.

Hepatitis B virus (HBV) and hepatitis C virus (HCV) are the major cause of the global burden of hepatitis. One of the main routes of transmission for both viruses is through exposure to infected blood, which includes sharing blood-contaminated syringes and needles. Human immunodeficiency virus (HIV) attacks the immune system and results in acquired immune deficiency syndrome and opportunistic infections. The objective of this study was to assess the epidemiology of HBV and HCV infections among HIV-infected people who inject drugs (PWID). The study enrolled 100 PWID from different addiction centers of the city of Lahore in Pakistan. All subjects were HIV-infected males and were above 16 years of age. Screening of HBV and HCV infections was performed through immunochromatography tests and enzyme-linked immunosorbent assays. The prevalence of HCV and HBV infections among the 100 HIV-infected PWID was 55% and 6%, respectively. HIV monoinfection was found in 37% of the subjects, while triple infection was detected in 2% of the subjects. Majority of the HIV-infected PWID were using heroin and Avil injections (65%). Half of the subjects had used injection drugs for 1-5 years, while 32% had used injection drugs for 6-10 years. HCV infection was more common than HBV infection among the enrolled subjects. Most of the PWID were practicing heroin and Avil injections.

DNA binding is essential for PprI function in response to radiation damage in Deinococcus radiodurans.

The extremely radioresistant bacterium Deinococcus radiodurans possesses a rapid and efficient but poorly known DNA damage response mechanism that mobilizes one-third of its genome to survive lethal radiation damage. Deinococcal PprI serves as a general switch to regulate the expression of dozens of proteins from different pathways after radiation, including the DNA repair proteins RecA, PprA and SSB. However, the underlying mechanism is poorly understood. In this study, we analyzed the dynamic alteration in global transcriptional profiles in wildtype and pprI mutant strains by combining microarrays and time-course sampling. We found that PprI up-regulated transcription of at least 210 genes after radiation, including 21 DNA repair and replication-related genes. We purified PprI and a helix-turn-helix (HTH) domain mutant and found that PprI specifically bound to the promoters of recA and pprA in vitro but did not bind nonspecific double-strand DNA. Chromatin immunoprecipitation (ChIP) assays confirmed that PprI specifically interacted with the promoter DNA of recA and pprA after radiation. Finally, we showed that a DNA-binding activity-deficient pprI mutant only partially restored resistance of the pprI mutant strain to γ radiation, UV radiation, and mitomycin C. Taken together, these results indicate that DNA-binding activity is essential for PprI to program the DNA repair process and cellular survival of D. radiodurans in response to radiation damage.