HBsAg seropositivity among multi-transfused thalassemic children.

Thalassemia major patients are transfusion dependent; they are at high risk of post transfusion viral infections including Hepatitis B virus (HBV). The present study was undertaken to find out the proportion of HBV infection among multiple transfused patients. This cross-sectional study was conducted among thalassemic children of either sex between 2 to 13 years of age, who attended the tertiary care hospital (G. G. Hospital, Jamnagar). Subjects were divided according to number of transfusions and the immunization status. HBsAg was detected by ELISA. Of 90 patients 6 (6.6%) were positive for HBsAg. Of 29 patients who had received above hundred transfusions 3 (10.34%) were sero-positive for HBV. Un-immunized patients were at double risk for acquiring HBV infection. This study suggests that the screening of blood of donors for HBV should be strictly followed and implementation of immunization against HBV is a must, especially in a high-risk group like thallasemic patients.

Chlamydia trachomatis antigen detection in pregnancy and its verification by antibody blocking assay.

PURPOSE: To detect the prevalence of genital infection caused by Chlamydia trachomatis in pregnant women and also to confirm the positive results using blocking antibody assay. METHODS: Endocervical specimens were collected from 200 symptomatic and asymptomatic pregnant women attending the ANC OPD at M P Shah Medical College, Jamnagar. The samples were tested for presence of Chlamydia trachomatis antigen using the monoclonal antibody. Blocking antibody assay was used to further verify the positive results. RESULTS: Out of 200 pregnant women, 38 (19%) were found positive for Chlamydia trachomatis antigen. Out of the 68 symptomatic patients, C. trachomatis antigen was detected in 26.4%. After verification of the positive samples 13.6% of the asymptomatic pregnant women were found to be harbouring the infection in their genital tract. Two (5.2%) out of the 38 positive samples, on verification with the blocking antibody assay, were found to be false positive by IDEIA,TM thus the specificity of the IDEIATM being 94.8%. In patients with previous history of abortions, 27.7% were tested positive for C. trachomatis infection. CONCLUSIONS: Significant number of pregnant women shad C. trachomatis antigen in their endocervical canal, which can be easily diagnosed by this simple enzyme immuno assay having a specificity of 94.8%. Verification of positive results by antibody blocking assay can further improve the specificity of this non-culture test. Asymptomatic patients should also be screened for the infection. History of previous abortions places the patient at a higher risk for C. trachomatis infection thus such patients should be definitely tested for chlamydia infection.

Anti-HIV inhibitors based on nucleic acids: emergence of aptamers as potent antivirals.

The development of resistance and the inability of currently approved antiretroviral drugs to completely eradicate HIV-1 have led to increased focus on therapies other than small molecules. Although nucleic acid-based intervention requires complex tasks involving intracellular delivery and/or stable expression in target cells, recent advances in gene therapy methods combined with continued progress in stem cell approaches have made nucleic acid-based compounds excellent candidates for effectively inhibiting intracellular targets. Consequently, multiple nucleic acid-based therapies are being developed. These include antisense nucleic acids, peptide nucleic acids and RNA decoys, which can interfere with HIV-1 replication. More recently, RNA interference, which exploits a novel cellular pathway, has been shown to effectively reduce viral titers in cell culture and promises to be a potential candidate for suppressing HIV replication in vivo. A promising candidate in the midst of these emerging approaches is the aptamer approach, which involves the use of a class of small nucleic acid molecules isolated from combinatorial libraries by an in vitro evolution protocol termed SELEX. Aptamers exhibit exquisite specificity, high affinity and the virtual lack of immunogenicity, features that make them exceptionally well-suited to combat HIV without affecting the host. The powerful nature of these specific antagonists of protein function could lead to the development of an effective anti-HIV therapy. Several highly specific, nucleic acid aptamers targeting select HIV proteins have been described. Investigations with anti-HIV RNA aptamers have shown an effective block to viral replication. This review summarizes the existing nucleic-acid based approaches to block HIV replication and attempts to chart the current progress in the development of aptamers against HIV, their use in inhibiting the virus replication, prospects for their use in the clinic and potential drawbacks.

Perinatally cotransmitted human herpesvirus 6 is activated in children born with human immunodeficiency virus infection.

OBJECTIVE: To evaluate the mother-to-child transmission profile of human immunodeficiency virus (HIV) as well as human herpesvirus 6 (HHV-6) and to examine active replication of HHV-6 in the HIV-infected mothers and their newborns. STUDY DESIGN/METHODS: This polymerase chain reaction (PCR)-based detection was done using DNA from peripheral blood mononuclear cells (PBMCs) and milk cells from the mothers, PBMC from the newborns, and DNA derived from plasma and cell-free milk fluid from mothers and plasma of the newborns. None of the mothers received antiretroviral treatment. RESULTS: HIV was transmitted to 50% newborns and, of 36 total mothers, 8 had actively replicating HHV-6 detectable in their plasma and 2 also had it in the lactosera. Among the neonates. HHV-6 was found in the PBMC DNA of seven and in the plasma fractions of five, the latter five newborns were all HIV-infected at birth. CONCLUSION: Perinatally cotransmitted HHV-6 was always activated in the neonates who were born with HIV infection. Also, HHV-6 can be detected in the milk cells and the activated virus may be present in the lactosera of some of these HlV-infected mothers.

Antibiotic sensitivity of enterobacteriaceae by disc diffusion and rapid fermentation sensitivity test methods.

A total of 400 strains of Gram negative bacilli were examined both by conventional disc diffusion (DD) and by rapid fermentation sensitivity test (RFST) methods. Various strains which were examined included Esch. coli Kleb. aerogenes, Kleb. pneumoniae, Prot. vulgaris, Prot. mirabilis, Prot. morgani, Prot. rittgeri and Providencia. The antibiotics used were streptomycin, chloramphenicol, kanamycin, gentamycin and ampicillin. The correlation between the two methods was found to vary from 75 to 98 per cent. By RFST method the results are obtained within six hours. The limitations of this method are (i) it cannot be used for Pseudomonas aeruginosa as it does not ferment glucose, (ii) it cannot be used for antibiotics active only at acidic pH like tetracycline and (iii) partial or intermediate sensitivity cannot be tested by this method. On the other hand, it is a simple, inexpensive, rapid and reliable method feasible in small laboratories also. The results are not affected by the size of inoculum or quality of medium (agar) used. Thus, it is very helpful especially when immediate antibiotic sensitivity is required.