Résumé
Background & objectives: the level of infant and child mortality is high among Scheduled Tribes particularly those living in rural areas. This study examines levels, trends and socio-demographic factors associated with infant and child mortality among scheduled tribes in rural areas. Methods: Data from the three rounds of the National Family Health Survey (NFHS) of India from 1992 to 2006 were analysed to assess the levels and trends of infant and child mortality. Univariate and multivariate Cox proportional hazard model were used to understand the socio-economic and demographic factors associated with mortality during 1992–2006. Results: Significant change was observed in infant and child mortality over the time period from 1992-2006 among Scheduled Tribes in rural areas. After controlling for other factors, birth interval, household wealth, and region were found to be significantly associated with infant and child mortality. Hazard of infant mortality was highest among births to mothers aged 30 yr or more (HR=1.3, 95% CI=1.1-1.7) as compared with births to the mother’s aged 20-29 yr. Hazard of under-five mortality was 42 per cent (95% CI=1.3-1.6) higher among four or more birth order compared with the first birth order. The risk of infant dying was higher among male children (HR = 1.2, 95% CI=1.1-1.4) than among female children while male children were at 30 per cent (HR=0.7, 95% CI=0.6-0.7) less hazard of child mortality than female children. Literate women were at 40 per cent (HR=0.6, 95% CI=0.50-0.76) less hazard of child death than illiterate women. Interpretation & conclusions: Mortality differentials by socio-demographic and economic factors were observed over the time period (1992-2006) among Scheduled Tribes (STs) in rural India. Findings support the need to focus on age at first birth and spacing between two births.
Résumé
A repertoire of monoclonal antibodies (mAbs) was generated against the midgut proteins of Anopheles culicifacies mosquitoes. The mAbs AC-43 and AC-29 signifi cantly inhibited Plasmodium vivax development inside the mosquito midgut. The number of oocysts that developed was reduced by 78.6% when mosquitoes ingested a combination of these two mAbs along with the blood meal. AC-43 mAb binds to the epitope common in 97, 80 and 43 kDa polypeptides from the midgut protein extract, as indicated by western blot analysis. Similarly, the mAb AC-29 recognized 52, 44, 40 and 29 kDa polypeptides. These female midgut-specifi c polypeptides are shared between An. culicifacies and An. stephensi, two major vectors of malaria in India. Deglycosylation assays revealed that O-linked carbohydrates are the major components in epitopes corresponding to AC-43 and AC-29. Gold particle labelling revealed that both these mAbs preferentially bind to glycoproteins at the apical microvilli and the microvillus-associated network present inside transverse sections of the gut epithelium. These regions are particularly known to have receptors for ookinetes, which enable them to cross this epithelial barrier and provide them with certain necessary chemicals or components for further development into oocysts. Therefore, these glycoproteins appear to be potential candidates for a vectordirected transmission-blocking vaccine (TBV).
Résumé
With a view to use mice as an experimental model for studying immune response to bovine rotavirus (BRV), the kinetics of humoral and cellular immune responses to BRV in mice were evaluated by immunizing through intraperitoneal and oral route with UK strain of BRV. Following immunization with BRV, anti-rotavirus antibodies was developed in mice. The mean log antibody titres as measured by ELISA in mice immunized by intraperitoneal route were significantly higher than those immunized by oral route. Significant cellular immune response was observed in BRV-immunized mice on stimulation with BRV antigen, as measured by lymphocyte proliferation assay. The thymidine uptake by splenic and mesenteric lymph-node cells of intraperitoneally immunized mice on stimulation with BRV was 21328 +/- 1225 and 739 +/- 55 CPM, respectively. The splenic cells showed significantly higher stimulation (stimulation index 12.98) as compared to those of mesenteric cells (stimulation index 1.57). Foot pad inoculation test showed maximum virus-specific delayed type hypersensitivity reaction at 24 hr post-challenge following primary immunization and at 18 hr post-challenge following secondary immunization. The results indicate that BRV immunization by intraperitoneal route generates more efficient immune response in mice than by oral route and this route may be used for immune response studies involving BRV infection.