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Biomedical subjects

A K Upadhyay

Publications and source records attributed to A K Upadhyay.

10 recordsLinked to original sources
PubMed2006

Wash resistance and bioefficacy of Olyset net--a long-lasting insecticide-treated mosquito net against malaria vectors and nontarget household pests.

During recent years, long-lasting insecticide-treated nets (LLINs) have been developed to overcome the problems of low retreatment rates, washing, and erratic dose of the insecticide resulting in the dilution of efficacy of the conventional insecticide-treated mosquito nets. These nets are treated at factory level with insecticide either incorporated into or coated around fibers. Olyset net, a polyethylene net with 2% permethrin incorporated within fibers, is one type of LLIN. Therefore, these nets were evaluated for their wash resistance and bioefficacy against malaria vectors Anopheles culicifacies Giles and Anopheles fluviatilis James (Diptera: Culicidae) and other nontarget species. Cone bioassay tests produced 100% mortality in these two vector species with 3-min exposure. Results of the bioassays on washed nets showed 100% mortality in An. fluviatilis even after 20 washings, whereas in An. culicifacies 100% mortality up to 11 washings and 80% mortality up to 20 washings were observed. Cone bioassay tests also were performed on nontarget mosquito species Culex quinquefasciatus Say; house fly, Musca domestica L.; American cockroach, Periplaneta americana (L.); head louse, Pediculus humanus capitis De Geer; and bed bug, Cimex lectularius L. with 30-min exposure. Except for bed bugs, 100% mortality was observed in these nontarget species after 24-h recovery period. In bed bugs, only 25% mortality was observed. The density of An. culicifacies and An. fluviatilis was significantly reduced in houses with Olyset nets compared with those with untreated nets or no nets. Thus, it may be concluded that Olyset nets are highly effective against malaria vectors and moderately against other nontarget household insects.

Animals↗
PubMed2006

Effectiveness of mosquito nets treated with a tablet formulation of deltamethrin for malaria control in a hyperendemic tribal area of Sundargarh District, Orissa, India.

A village-scale trial on the efficacy of mosquito nets treated with a tablet formulation of deltamethrin (K-OTAB) against malaria in comparison to untreated nets or no net was conducted in Sundargarh District of Orissa, India, which is characterized by perennial transmission with Plasmodium falciparum accounting for more than 80% of malaria cases. Three villages with similar topographical and epidemiological situations were selected and randomly assigned to 3 arms of the study: treated net, untreated net, and no net. Distribution of nets, based on a sleeping pattern survey, was carried out to cover 100% of the population in treated-net and untreated-net villages. Longitudinal and cross-sectional surveys were conducted to measure malaria incidence, prevalence, and splenomegaly. Malaria incidence was reduced by 64.3% in the village with treated nets, 45.2% in the village with plain nets, and 21.4% in the control village without nets. Comparison of malaria incidence data after 1 year of intervention showed significant difference between villages with treated net vs. untreated net (P < 0.05) and treated net vs. no net (P < 0.005). The incidence of clinical attack rate due to P. falciparum was significantly lower in the population using treated nets than in those using untreated nets and no nets. However, no age-specific protective efficacy of treated nets or untreated nets was observed. A significant reduction occurred in spleen rate and parasite rate in children aged 2-9 years using treated nets or untreated nets. An overall significant reduction was found in parasite rate in the total population using treated and untreated nets as compared to nonusers.

Adolescent↗
PubMed2005

Village-scale evaluation of mosquito nets treated with a tablet formulation of deltamethrin against malaria vectors.

A field trial was carried out in the Sundargarh district of Orissa, India on the efficacy of mosquito nets treated with a tablet formulation of deltamethrin (K-O TAB) against malaria vectors. Treated nets were used in one village, and in the two control villages, one used untreated nets and the other used indoor spraying with DDT, without nets. In this area the primary malaria vectors are Anopheles culicifacies Giles sensu lato (Diptera: Culicidae) and An. fluviatilis James s.l., which are both endophagic and endophilic, and fully susceptible to deltamethrin. Treatment of a 10-m(2) mosquito net with one of the tablets gave a deltamethrin deposit of 25 mg/m(2). Bioassays repeated on domestically used nets over 7 months showed persistence of almost 100% mortality of An. fluviatilis, whereas An. culicifacies showed a decline from 100% to 71% mortality over this period, after which the nets were re-treated and bioassays were not continued. The sum of collections of mosquitoes resting in village houses and those in exit traps and dead on floor sheets showed a reduction in the numbers of the two vector species due to the treated nets, compared with untreated or no nets, but no reduction in other anophelines or Culex species. Large proportions of the collections of the vector and non-vector anophelines were dead on the floor sheets, but among Culex, mortality was delayed. Treated and untreated nets reduced the proportion of anophelines that had blood-fed; the treated nets did so more effectively than the untreated in the case of An. culicifacies and of Culex mosquitoes. In rooms with treated nets a larger proportion of the total collections [dead + live] were in the exit traps, which can be attributed to the excito-repellent effect of deltamethrin. It is easier to pack and handle tablets of insecticide than liquid concentrate and the use of one tablet per net may be preferable to making up a large volume of diluted insecticide and dipping many nets at a time.

Animals↗
PubMed2005

A new flavanone, reflexin, from Cuscuta reflexa and its selective sensing of nitric oxide.

A new compound, reflexin, 5-hydroxy-7-methoxy-6-(2,3-epoxy-3-methylbutyl)-flavanone, is isolated from the stems of Cuscuta reflexa along with three other known compounds. This new compound has good potential for application especially in the photoactivity of reflexin. It was found to be sensitive to glutathione, forming a fluorescent product that is utilized for sensing nitric oxide (NO). The lowest detection limit of NO analysis was found to be 0.05 micro/M.

Biosensing Techniques↗
PubMed2001

Antioxidant property of Smilex china Linn.

Smilex china Linn. (Smilacaceae Syn Liliaceae) has special pharmacognostic feature as its root is multiseriate, with sclerenchymatic pericycle. The alcoholic extract of rhizome of S. china shows significant protection against FeSO4 induced lipid peroxidation in rat liver homogenate, but has no effect on the rate of oxidation of reduced glutathione. This fraction scavenges the superoxide and hydroxyl radicals, but the effect was more towards the removal of superoxide than that of hydroxyl radicals. Thus it could be concluded that rhizome of S. china has strong antioxidant property.

Animals↗
PubMed1997

Field trial of Bacillus sphaericus strain B-101 (serotype H5a, 5b) against filariasis and Japanese encephalitis vectors in India.

A large-scale operational field trial was conducted from June 1993 to October 1994 to evaluate the efficacy of Bacillus sphaericus (strain B-101, serotype H5a,5b) for control of the vectors of filariasis (Culex quinquefasciatus) and Japanese encephalitis (Cx. tritaeniorhynchus and Cx. vishnui) in Rourkela city. Application of B. sphaericus, when sprayed at 1 g/m2 in storm drains, wastewater pools, abandoned masonry tanks, peripheral paddy fields, ditches, and other small water collections and at 4 g/m2 in domestic septic tanks, significantly reduced larval and pupal counts (P < 0.0001) and significantly reduced the percentage of habitats containing larvae (3rd-4th instars) (P < 0.0001) as compared with routine antilarval measures. This in turn resulted in a reduction in the indoor density of disease vectors in particular and a reduction in mosquito nuisance in general. The trial demonstrated that B. sphaericus has good potential for use against disease vectors and mosquito breeding in polluted as well as clean waters.

Animals↗
PubMed1991

Lack of effect of islet amyloid polypeptide in causing insulin resistance in conscious dogs during euglycemic clamp studies.

In this study, we administered constant intravenous infusions of human islet amyloid polypeptide (hIAPP) to conscious dogs during euglycemic glucose-clamp studies. The doses of hIAPP used (5 and 50 pmol.kg-1.min-1) raised the circulating IAPP levels approximately 12- and 50-fold above basal levels, respectively. Studies were conducted at two different insulin infusion rates, resulting in steady-state plasma insulin levels of approximately 600 and 2800 pM. According to our results, the hIAPP infusions did not lead to any measurable change in the insulin-stimulated glucose disposal rate at either insulin infusion rate. Additionally, we observed no effect of IAPP on hepatic glucose production. Although we did not observe any effect of hIAPP on any of the aspects of glucose or insulin metabolism measured, we did find a consistent hypocalcemic effect of this peptide at the 50-pmol.kg-1.min-1 infusion rate. Shortly after the onset of hIAPP infusion, serum calcium levels fell by 10-15% and remained at these levels throughout the course of the hIAPP infusion. In summary, 1) infusion of hIAPP at doses of 5 or 50 pmol.kg-1.min-1 in conscious dogs raised the circulating IAPP level 12- to 50-fold above basal; 2) during these infusion studies, no effect of hIAPP was observed on any of the aspects of glucose or insulin homeostasis measured; 3) 50 pmol.kg-1.min-1 hIAPP lead to a prompt reduction in plasma calcium concentrations with intravenous administration.

Amyloid↗
PubMed1989

Cystic nephroma: an emerging entity.

Cystic nephroma is a rare lesion, but there has been an increased number of cases reported in the recent literature. Most cases have been discovered incidentally either on routine examination or during radiological investigations. There are two peaks of incidence, one in childhood and one in middle age and the condition is often wrongly presumed to be a malignant tumor. Cystic nephroma is a benign neoplasm and it can be confidently diagnosed using modern imaging techniques and tissue analysis. Classically, the treatment of cystic nephroma has been simple nephrectomy, although a few cases have been treated by enucleation. Simple nephrectomy is the treatment of choice in children as the diagnosis in the young is less exact and a cure is assured. In some adult patients it is reasonable to pursue a conservative policy with regular clinical and ultrasound examinations.

Adult↗