Genetic analysis of foot-and-mouth disease virus serotype A of Indian origin and detection of positive selection and recombination in leader protease- and capsid-coding regions

The leader protease (Lpro) and capsid-coding sequences (P1) constitute approximately 3 kb of the foot-and-mouth disease virus (FMDV). We studied the phylogenetic relationship of 46 FMDV serotype A isolates of Indian origin collected during the period 1968-2005 and also eight vaccine strains using the neighbour-joining tree and Bayesian tree methods. The viruses were categorized under three major groups-Asian, Euro-South American and European. The Indian isolates formed a distinct genetic group among the Asian isolates. The Indian isolates were further classified into different genetic subgroups ( < 5% divergence). Post-1995 isolates were divided into two subgroups while a few isolates which originated in the year 2005 from Andhra Pradesh formed a separate group. These isolates were closely related to the isolates of the 1970s. The FMDV isolates seem to undergo reverse mutation or convergent evolution wherein sequences identical to the ancestors are present in the isolates in circulation. The eight vaccine strains included in the study were not related to each other and belonged to different genetic groups. Recombination was detected in the Lpro region in one isolate (A IND 20/82) and in the VP1 coding 1D region in another isolate (A RAJ 21/96). Positive selection was identified at aa positions 23 in the Lpro (P < 0.05; 0.046∗) and at aa 171 in the capsid protein VP1 (P < 0.01; 0.003∗∗)

Fast Dissolving Tablets of Fexofenadine HCl by Effervescent Method

In the present work, fast dissolving tablets of fexofenadine HCl were prepared by effervescent method with a view to enhance patient compliance. Three super-disintegrants viz., crospovidone, croscarmellose sodium and sodium starch glycolate along with sodium bicarbonate and anhydrous citric acid in different ratios were used and directly compressible mannitol (Pearlitol SD 200) to enhance mouth feel. The prepared batches of tablets were evaluated for hardness, friability, drug content uniformity and in vitro dispersion time. Based on the in vitro dispersion time (approximately 20 s), three formulations were tested for in vitro drug release pattern in pH 6.8 phosphate buffer, short-term stability at 40°/75% RH for 3 mo and drug-excipient interaction (IR spectroscopy). Among the three promising formulations, the formulation ECP3 containing 8% w/w of crospovidone and mixture of 24% w/w sodium bicarbonate 18% w/w of anhydrous citric acid emerged as the best (t50% 4 min) based on the in vitro drug release characteristics compared to conventional commercial tablet formulation (t50% 15 min). Short-term stability studies on the formulations indicated that there are no significant changes in drug content and in vitro dispersion time (P<0.05)

Genetic characterization of Indian type O FMD virus 3A region in context with host cell preference

The 3A region of foot-and-mouth disease virus has been implicated in host range and virulence. For example, amino acid deletions in the porcinophilic strain (O/TAW/97) at 93-102 aa of the 153 codons long 3A protein have been recognized as the determinant of species specificity. In the present study, 18 type O FMDV isolates from India were adapted in different cell culture systems and the 3A sequence was analyzed. These isolates had complete 3A coding sequence (153 aa) and did not exhibit growth restriction in cells based on species of origin. The 3A region was found to be highly conserved at N-terminal half (1-75 aa) but exhibited variability or substitutions towards C-terminal region (80-153). Moreover the amino acid substitutions were more frequent in recent Indian buffalo isolates but none of the Indian isolates showed deletion in 3A protein, which may be the reason for the absence of host specificity in vitro. Further inclusive analysis of 3A region will reveal interesting facts about the variability of FMD virus 3A region in an endemic environment

Molecular Epidemiology of Rabies Virus Isolates in India

In India, rabies is enzootic and is a serious public health and economic problem. India has a large population of stray dogs which, together with a lack of effective control strategies, might have led to the persistence of rabies virus (RV) in the canine population. Our objective was to study the molecular epidemiology of RV isolates in India based on nucleotide sequence analysis of 29 RV isolates originating from different species of animals in four states. Here we have analyzed two sets of sequence data based upon a 132-nucleotide region of the cytoplasmic domain (CD) of the G gene (G-CD) and a 549-nucleotide region (Psi-L) that combines the noncoding G-L intergenic region (Psi) and a fragment of the polymerase gene (L). Phylogenetic analysis revealed that the RV isolates belong to genotype 1 and that they were related geographically but were not related according to host species. Five different genetic clusters distributed among three geographical regions were identified. Comparison of the deduced amino acid sequences of G-CD between RV isolates revealed three amino acid changes (amino acid 462G [aa462G], aa465H, and aa468K) that distinguished the Indian RVs from RV isolates in other parts of the world. Analysis of the data indicated that the dog rabies virus variants are the major circulating viruses in India that transmit the disease to other domestic animals and humans as well

Zona pellucida-based contraceptive vaccines for human and animal utility

Contraceptive vaccines can be designed to inhibit (i) production of the gametes (sperm and oocyte), (ii) functions of gametes leading to block in fertilization, and (iii) the gamete outcome (pregnancy). The zona pellucida (ZP) glycoproteins have been proposed as candidates for developing contraceptive vaccines by virtue of their critical role in fertilization. Immunization of non-human primates with either native or recombinant ZP proteins leads to curtailment of fertility, which however is invariably associated with ovarian pathology. To avoid oophoritis, immunogens corresponding to mapped B cell epitopes of ZP proteins that are devoid of 'oophoritogenic' T cell epitopes have been proposed. However, ways to overcome the observed oophoritis associated with the ZP-based contraceptive vaccines are yet to be fully defined. This is essential if their use for control of human fertility is to be considered. Nonetheless, contraceptive vaccines based on ZP proteins have shown very promising results in controlling wildlife population such as wild horses, white-tailed deers, elephants, marsupials, grey seals and dogs, where long term infertility or even permanent sterility is desirable