The CFTR gene mild variants poly-T, TG repeats and M470V detection in Indian men with congenital bilateral absence of vas deferens

The aim of the study was to detect the frequency of the CFTR gene variants poly-T, TG repeats and c.1408A>G p.Met470Val (M470V) in Indian men with congenital bilateral absence of the vas deferens (CBAVD). Men diagnosed with CBAVD (n = 76), their female partners (n = 76) and healthy men from general population (n = 50) were recruited. Genomic DNA was isolated and the polymorphic regions of IVS9- c.1210-12T [5] and M470V were amplified using specific primers followed by Sanger's DNA sequencing. A statistically significant increase in the frequency of heterozygous IVS9- c.1210-12T [5] (39.4%) was observed in CBAVD men as compared to controls (14%). The allelic distribution of c.1210-12T [5], c.1210-12T [7] and c.1210-12T [9] in CBAVD men was 21%, 64.4% and 13% and that in healthy controls was 7%, 73% and 20% respectively. Longest TG repeat c.1210-34TG [13] was found in association with c.1210-12T [5] with an allelic frequency of 5.9% in CBAVD men. We found a significant association of c.1210-34TG [12]/c.1210-34TG [13] - c.1210-12[5] -V470 allele in CBAVD men. Twelve female partners harboured a heterozygous c.1210-12T [5] allele. The study emphasises the need to screen both partners for the polymorphisms M470V, poly-T, TG tract repeats in addition to population-specific known CFTR gene mutations.

Fipronil-induced genotoxicity and DNA damage in vivo: Protective effect of vitamin E

Fipronil, an insecticide of the phenylpyrazole class has been classified as a carcinogen by United States Environmental Protection Agency, yet very limited information is available about its genotoxic effects. Adult male and female animals were gavaged with various doses of fipronil (2.5, 12.5, and 25 mg/kg body weight (bw)) to evaluate micronucleus test (mice), chromosome aberration (CA), and comet assay (rats), respectively. Cyclophosphamide (40 mg/kg bw; intraperitoneal) was used as positive control. Another group of animals were pretreated with vitamin E orally (400 mg/kg bw) for 5 days prior to administration of fipronil (12.5 mg/kg). Fipronil exposure in both male and female mice caused significant increase in the frequency of micronuclei (MN) in polychromatic erythrocytes. Similarly, structural CAs in bone marrow cells and DNA damage in the lymphocytes was found to be significantly higher in the male and female rats exposed to fipronil as compared to their respective controls. The average degree of protection (male and female animals combined together) shown by pretreatment of vitamin E against fipronil-induced genotoxicity was 63.28%: CAs; 47.91%: MN formation; and 74.70%: DNA damage. Findings of this study demonstrate genotoxic nature of fipronil regardless of gender effect and documents protective role of vitamin E.

HOXBES2: a novel epididymal HOXB2 homeoprotein and its domain-specific association with spermatozoa

The sperm from the testis acquires complete fertilizing ability and forward progressive motility following its transit through the epididymis. Acquisition of these characteristics results from the modification of the sperm proteome following interactions with epididymal secretions. In our attempts to identify epididymis-specific sperm plasma membrane proteins, a partial 2.83-kb clone was identified by immunoscreening a monkey epididymal cDNA library with an agglutinating monoclonal antibody raised against washed human spermatozoa. The sequence of the 2.83-kb clone exhibited homology to the region between 1 and 1097 bp of the homeobox gene, Hoxb2. This sequence was found to be species conserved, as revealed by RT-PCR analysis. To obtain a full-length clone of the sequence, 5' RACE-PCR (rapid amplification of cDNA ends PCR) was carried out using rat epididymal RNA as the template. It resulted in a full-length 1.657-kb cDNA encoding a 32.9-kDa putative protein. The protein designated HOXBES2 exhibited homology to the conserved 61-amino acid homeodomain region of the HOXB2 homeoprotein. However, characteristic differences were noted in its amino and carboxyl termini compared with HOXB2. A putative 30-kDa protein was detected in the tissue extracts from adult rat epididymis and caudal spermatozoa, and a 37-kDa protein was detected in the rat embryo when probed with a polyclonal antibody against HOXB2 protein. Multiple tissue Western blot and immunohistochemical analysis further indicated its expression in the cytoplasm of the principal and basal epithelial cells, with maximal expression in the distal epididymal segments. Northern blot analysis detected a single approximately 2.5-kb transcript from the adult epididymis. Indirect immunofluorescence localized the protein to the acrosome, midpiece, and equatorial segments of rat caudal and ejaculated human and monkey spermatozoa, respectively. In conclusion, we have identified and characterized a novel epididymal homeoprotein different from HOXB2 protein and hereafter referred to as HOXBES2, (HOXB2 homeodomain containing epididymis-specific sperm protein) with a probable role in fertilization.

Identification of T-helper and linear B epitope in the hypervariable region of nucleocapsid protein of PPRV and its use in the development of specific antibodies to detect viral antigen

Peste des petits ruminants is a highly contagious viral disease of small ruminants making its diagnosis difficult from the similar symptoms of Rinderpest. Computer based prediction algorithms was applied to identify antigenic determinants on the nucleocapsid (N) protein of PPRV. Specificity and antigenicity of each peptide was evaluated by solid phase ELISA. Six specific peptide sequences were evaluated in multiple antigenic peptide (MAP) form and immune response was evaluated by supplementing universal T-helper epitope human IL-1beta peptide (VQGEESNDK, amino acids 163-171). Out of the six peptides 19mer sequence corresponding to 454-472 region of N protein of PPRV was found to be highly immunogenic and specific to PPRV. Evaluation of overlapping peptides differing in length for this 452-472 region, showed minimum length of 14 amino acid residues were required for the stable affinity binding of antigen-antibody. The results of immunization and indirect ELISA indicated the presence of T-helper epitope at the N-terminal end and linear B epitope at the C-terminal region of 454-472 19mer of nucleocapsid peptide of PPRV-nucleocapsid protein. The antipeptide antibodies developed against this region showed specificity to PPRV antigen differentiating it from RPV when used in indirect ELISA and western blot analysis.

Enhanced esterase activity in salivary gland and midgut of Aedes aegypti mosquito infected with dengue-2 virus

Mosquitoes were infected by intrathoracic inoculation. About 95% head squashes were positive for dengue virus antigen on the 15th post infection day (PID). Esterase activity was determined in the homogenates prepared from the salivary glands and midguts on different PIDs of dengue virus inoculated and control mosquitoes showed that it was consistently higher in the virus-infected batches.