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Biomedical subjects

M A Ansari

Publications and source records attributed to M A Ansari.

At least 19 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

Bioefficacy of Olyset nets against mosquitoes in India.

Olyset nets are highly effective in killing anopheline mosquitoes within 3 min of exposure, as evidenced in cone bioassay tests. These nets also showed their efficacy on other vector mosquitoes (Aedes aegypti and Cx. quinquefasciatus) at higher exposure periods. The efficacy remained at approximately 90% even after 20 washings at an interval of 24 h against Anopheles culicifacies and Cx. quinquefasciatus. Use of the nets inside the house also resulted in drastic reduction of daytime resting density of mosquitoes because of high repellency, excitorepellency, and killing action of the nets. Pilot studies are indicated to evaluate the impact of use of Olyset nets on vector-borne diseases, particularly malaria, and its cost-effectiveness in comparison to conventional indoor residual spraying.

Aedes↗
PubMed2005

Therapeutic efficacy of antimalarial drugs along the eastern Indo-Nepal border: a cross-border collaborative study.

This collaborative cross-border study was performed to determine the therapeutic efficacy of antimalarial drugs used by the National Programmes for falciparum malaria along the eastern Indo-Nepal border where there is unregulated population movement across the border. The study was conducted at sites in Jhapa District, Nepal and Darjeeling District, India. The study was conducted from August 2003 to February 2004, following the WHO 28 day treatment protocol. The efficacy of chloroquine was tested in India among 91 subjects and of sulfadoxine-pyrimethamine in Nepal among 107 subjects with laboratory-confirmed Plasmodium falciparum malaria. Of the 102 subjects who completed the study in Nepal, there were 21 (20.6%) treatment failures comprising 7 (6.9%) early treatment failures (ETF) and 14 (14.7%) late treatment failures (LTF) (5 late clinical failures [LCF] and 9 late parasitological failures [LPF]). Of the 89 subjects who completed the study in India, there were 46 (51.7%) treatment failures comprising 7 (7.9%) ETFs and 39 (43.8%) LTFs (13 LCFs and 26 LPFs). Based on WHO guidelines both countries need to review their drug policy urgently and make appropriate changes, taking into account aspects of cross-border collaboration in the control of drug-resistant malaria.

Adolescent↗
PubMed2005

Foot infections.

Infections of the foot are very variable, some being complex in nature, causing pain, morbidity, and even mortality. In patients with diabetes mellitus, foot infections are common, ranging from chronic bacterial or fungal infections to serious limb-threatening ones. To manage infections, a sound knowledge of anatomy is essential. This article reviews the problems with respect to recent evidence and provides pathways to management and suggestions of changes with potential to wound healing.

Acute Disease↗
PubMed2005

Laboratory and field evaluation of Hilmilin against mosquitoes.

Hilmilin (diflubenzuron), an insect growth regulator, was tested for efficacy against Anopheles stephensi, Anopheles culicifacies, Aedes aegypti, and Culex quinquefasciatus in the laboratory and in field conditions. Fifty percent and 90% lethal concentrations (LC50 and LC90) of Hilmilin formulations were determined by exposing early 4th-stage larvae to serial dilutions of the formulation, and data were subjected to log probit analysis. Two doses (0.004 and 0.008 g/m2) were applied in different breeding habitats of mosquitoes with the help of stirrup pumps. Percent inhibition of adult emergence was compared according to a previously described procedure. Laboratory results revealed that both 25WP (wettable powder) and 22SL (semiliquid) formulations showed more or less the same degree of efficacy against tested mosquito species (P < 0.05). Of 4 species tested, An. stephensi was more susceptible, followed by An. culicifacies, Ae. aegypti, and Cx. quinquefasciatus. One hundred percent inhibition of adult emergence was observed at a dose of 0.0125 ppm (25WP and 22SL) against all mosquitoes tested in the laboratory. Both formulations showed almost similar effect when applied in the field at doses of 0.004 and 0.008 g/m2 in their respective preferential breeding habitats. However, the effect was more pronounced at a higher concentration (0.008 g/m2) against all species of mosquitoes. Hilmilin at a dose of 0.008 g/m2 can be used to contain mosquito breeding in stone quarries, pools, cement tanks, unused wells, unused coolers, and irrigation channels.

Aedes↗
PubMed2005

Larvicidal and mosquito repellent activities of Pine (Pinus longifolia, family: Pinaceae) oil.

BACKGROUND AND OBJECTIVES: Various plant-based products are safe and biodegradable alternatives to synthetic chemicals for use against mosquitoes. Oil of Pinus longifolia is traditionally used for protection against mosquitoes in some rural areas but there is no documented report of its use against mosquitoes. The present study was undertaken to scientifically evaluate the activity of Pine oil against mosquitoes. METHODS: The oil was procured from the market and its contents were chemically analysed. Larvicidal activity of oil was tested in laboratory bioassays, while repellent action was studied during whole night bait collections in field by direct application on the skin and after its impregnation on mats. RESULTS: Results showed varying degree of larvicidal activity of Pine oil against mosquitoes with LC50 values ranging between 82 and 112 ppm. The Pine oil had strong repellent action against mosquitoes as it provided 100% protection against Anopheles culicifacies for 11 h and 97% protection against Culex quinquefasciatus for nine hours respectively. Electrically heated mats prepared from Pine oil provided, 94 and 88% protection against An. culicifacies and Cx. quinquefasciatus for 10 and seven hours respectively. INTERPRETAION AND CONCLUSION: Pine oil is effective against mosquito larvae at very higher doses which are not of any practical utility. However, Pine oil showed strong repellent action against An. culicifacies (malaria vector) and Cx. quinquefasciatus (pest mosquito). Thus its use could be popularised as mosquito repellent.

Animals↗
PubMed2005

Efficacy of IGR compound Starycide 480 SC (Triflumuron) against mosquito larvae in clear and polluted water.

BACKGROUND AND OBJECTIVES: An environmental friendly formulation Starycide 480 SC (Triflumuron-OMS-2015 ), a new insect growth regulator with chitin synthesis inhibitor type mode of action was evaluated against mosquito larvae in laboratory and small-scale field trials carried out in and around Delhi. METHODS: The formulation was tested in laboratory for its bio-efficacy against late III instar mosquito larvae of different species using WHO bioassay procedure. In the field formulation was sprayed at doses of 0.3, 0.5 and 1 ppm (g/m3) in the natural breeding habitats of Anopheles and Culex mosquitoes. The impact was assessed by monitoring densities of larvae by dipper and observing the reduction in larval density and inhibition of adult emergence. RESULTS: In the laboratory, formulation was more effective against larvae of Anopheles stephensi and Aedes aegypti than Culex quinquefasciatus, but it produced 100% inhibition of adult emergence for all mosquito species at a concentration of 0.02 ppm. In the field trials, formulation did not produce 100% reduction in the density of late stage larvae even at 1 ppm (g/m3), the highest dose tested, but it resulted in 100% inhibition of pupal formation of both Anopheles and Culex spp in different types of habitats for 3-7 weeks even at a lower dose of 0.5 ppm. INTERPRETATION AND CONCLUSION: Application of triflumuron in the natural breeding habitats in both clean and polluted water @ 0.5 ppm (g/m3) resulted in complete inhibition of adult emergence of both Anopheles and Culex spp for 3-7 weeks. This formulation may be tested in large-scale field trials for further use in the vector control programme.

Animals↗
PubMed2004

Selection of a highly virulent fungal isolate, Metarhizium anisopliae CLO 53, for controlling Hoplia philanthus.

The June beetle, Hoplia philanthus Füessly (Coleoptera: Scarabaeidae), has become a widespread and destructive insect pest of lawns, sport turf, pastures, and horticultural crops in Belgium. The virulence of 34 entomopathogenic fungal isolates from the genera Metarhizium, Beauveria, and Paecilomyces to third-instar H. philanthus was tested in bioassays by dipping larvae in 10(7)conidia/ml suspensions. Two isolates of Metarhizium anisopliae (CLO 53 and CLO 54) caused maximally 90% mortality 10 weeks post-inoculation while other isolates only caused mortalities between 10 and 62%. The virulence of M. anisopliae CLO 53 was further tested by exposing H. philanthus larvae to conidial serial concentrations of 10(4)-10(9)conidia/g sandy soil for up to 11 weeks at 15, 20 or 25 degrees C. Mortality was dependant on the fungal concentration, exposure time, and temperature. Eleven weeks after inoculation, the LC50 values for this isolate ranged from 1.3 to 4.0 x 10(6), 1.0 to 3.2 x 10(5), and 2.5 x 10(4) to 10(5)conidia/g soil at 15, 20, and 25 degrees C, respectively. The LT50 values for this isolate ranged from 3.5 to 21.7, 2.4 to 18.7, and 2.9 to 16.1 weeks at concentrations of 10(9) and 10(4)conidia/g soil at 15, 20, and 25 degrees C, respectively. In glasshouse pot experiment with perennial ryegrass (Lolium perenne L.), the isolate CLO 53 caused mortalities of 50 and 88% of H. philanthus larvae 10 weeks after application of 10(4) and 10(6)conidia/cm(2) soil surface, respectively. The present results suggest that the Belgian isolate CLO 53 has excellent potential for biological control of H. philanthus.

Animals↗
PubMed2003

Prevalence of the K76T mutation in the pfcrt gene of Plasmodium falciparum among chloroquine responders in India.

Chloroquine-resistant Plasmodium falciparum needs to be monitored in the field for effective malaria control strategies. A point mutation K76T in the P. falciparum chloroquine resistance transporter (Pfcrt) protein has recently been proposed as a molecular marker for the faster detection of chloroquine-resistant falciparum malaria in field. We describe here the evaluation of this marker in Indian P. falciparum isolates. A total of 274 Indian P. falciparum isolates were analyzed for the K76T mutation. This mutation was detected in all the clinical isolates obtained from the in vivo chloroquine non-responders. But majority of the clinical isolates from chloroquine responders (71 of 74 patients, i.e. 96%) also harbored this mutation. The K76T mutation was indeed highly prevalent (91%) among 213 clinical isolates. There was a significant association between K76T mutation and the in vitro chloroquine response (P<0.05) but six isolates showed discordant results. In conclusion, the K76T mutation fails to differentiate majority of the chloroquine responders from that of the non-responders and thus will be of limited use in the field in India.

Adolescent↗
PubMed2001

Allelic variation in the cg2 gene does not correlate with chloroquine resistance among Indian Plasmodium falciparum isolates.

The cg2 gene of Plasmodium falciparum has been proposed to be associated with chloroquine resistance. Here we describe PCR amplification and sequencing of all the four repeat regions (kappa (kappa), gamma (gamma), psi (psi) and omega (omega)) of this gene, from Indian isolates. There were variant forms for each of these repeat regions (two for kappa and gamma, and three for psi and omega) among the 123 Indian isolates of P. falciparum. Among these isolates certain forms of psi and omega repeats were uniquely present while some of the reported forms of the kappa and omega repeats were absent. The pattern of combination of all four repeat regions of cg2 gene (genotype) was analysed from 52 isolates. A total of 11 different genotypes were observed among these cases, of which 10 were unique to Indian isolates. Certain genotypes were more common than others. The nucleotide sequencing of all the four repeat regions revealed that Indian isolates have some unique repeating units within the gamma and omega domains. Altogether, the PCR and sequencing results showed that there was an unrelatedness between cg2 repeats and chloroquine resistance.

Alleles↗
PubMed2001

Lessons to be learned: a case study approach. Paraganglioma of the urinary bladder.

Primary paraganglioma arises infrequently in the urinary bladder. We present here the clinicopathological, immunohistochemical and ultrastructural findings in a 23-year-old Saudi female. She was hospitalised because of gross haematuria over the previous seven days. The intravenous urogram revealed a filling defect in the urinary bladder. Cystoscopy disclosed a non-papillary tumour arising from the roof of the bladder neck. Transurethral resection was, accordingly, performed--but marked fluctuation in blood pressure was observed during the procedure. The histopathological findings of trabeculae and small nests of plump oval to spindle cells with a clear to acidophilic cytoplasm, forming an organoid pattern and demonstrating inconspicuous mitotic activity, were diagnostic of paraganglioma of the urinary bladder, the diagnosis was confirmed by means of immunohistochemical and ultrastructural studies. The endocrine markers chromogranin A and neuron-specific enolase were positive in chief cells; sustentacular cells at the periphery of neoplastic cell clusters were positive for S-100 protein. Neurosecretory granules were identified by electron microscopic examination. It is emphasised that, currently, there are no anatomico-pathological criteria to distinguish benign and malignant forms of the disease. Post-surgical recovery was uneventful in this case. Recurrence and metastases, though infrequent, have been reported in the literature; therefore, radiation therapy may be an important adjunct--and long-term follow-up is mandatory.

Adult↗
PubMed2001

Concurrent control of mosquitoes and domestic pests by use of deltamethrin-treated curtains in the New Delhi Municipal Committee, India.

A field trial was conducted in Block F of the Moti Bagh area of New Delhi Municipal Committee to demonstrate composite control of Anopheles stephensi and Aedes aegypti by spraying deltamethrin at 100 mg/m2 on window and door curtains of habitations. Results revealed drastic reduction (87.9-93.7%, P < 0.05) of target species in the experimental area. The impact of deltamethrin-treated curtains was also evident against nontarget species (67.9-85.7%. P < 0.05). Treated curtains provided 100% kill of An. stephensi and Ae. aegypti for 3-4 months, followed by a gradual decline in successive months. Use of deltamethrin-treated curtains resulted in 92.0 reduction in slide positivity rate and 95.4% reduction in malaria cases per thousand population. The cost of deltamethrin treatment was Rs 41.15 (<$1 U.S.) per house per annum. Insecticide-treated mosquito window and door curtains, along with legislative measures, may provide cost-effective concurrent control of mosquitoes and other domestic pests.

Aedes↗
PubMed2001

Correlation between AgNOR count and subjective AgNOR pattern assessment score in cytology and histology of breast lumps.

OBJECTIVE: To find the correlation of argyrophilic nucleolar organizer region (AgNOR) count and subjective AgNOR pattern assessment (SAPA) score in cytology and histology of breast lumps. STUDY DESIGN: The study group consisted of 73 patients (46 malignant, 27 benign) with breast lumps. In all cases, fine needle aspiration cytology (FNAC) samples and histologic specimens were studied by conventional and silver staining for AgNORs. RESULTS: AgNOR count and SAPA score were helpful in differentiating benign from malignant tumors in both the cytologic smear and histologic specimen. AgNOR count was 6.94+/-2.74 in FNAC and 6.57+/-2.73 in histology of malignant tumors, while in benign tumors it was 2.75+/-0.74 in FNAC and 2.68+/-0.77 in histology. SAPA score was 9.02+/-4.60 in FNAC and 8.76+/-2.34 in histology in malignant tumors and 5.87+/-0.93 in FNAC and 5.82+/- 0.83 in histology in benign tumors. CONCLUSION: Both AgNOR count and SAPA score gave similar results, but SAPA score is a more convenient, reproducible and rapid method of AgNOR evaluation.

Biopsy, Needle↗
PubMed2001

Epidemiologic investigations of a malaria outbreak in northern Delhi area.

Epidemiologic investigations revealed a 56.7 and 13.32% slide positivity rate in febrile and afebrile malaria cases, respectively. In both cases, Plasmodium falciparum was predominant. Anopheles culicifacies resistant to dichlorodiphenyltrichloroethane and benzene hexachloride (hexachlorocyclohexane) was found breeding profusely in pools and ponds created by excavation of earth around brick kiln in the region. Furthermore, children were not found to be producing significant levels of antibodies and a large percentage of patients harbored chloroquine-resistant parasites. Also, more than 1 P. falciparum strain was present in the population. We detected 2 strains, VI and VII, of which type VI was predominant.

Adolescent↗
PubMed2000

Synthesis of arene-soluble mixed-metal Zr/Ce, Zr/Y, and related [[Zr2(OiPr)9]LnX2]n complexes using the dizirconium nonaisopropoxide ligand.

The utility of polydentate monoanionic [Zr2(OiPr)9]- in generating arene-soluble, unsolvated, mixed-metal Zr/Ce and Zr/Y complexes is described. The synthesis of other mixed-metal zirconium lanthanide complexes was also studied to explore the relationship of metal size to structure. Lanthanide trihalides react in THF with KZr2(OiPr)9 to form unsolvated dimers, [[Zr2(OiPr)9]LnCl2]2, with the larger metals, Ln = Ce (1), Ho (2), Y (3), and unsolvated monomers, [Zr2(OiPr)9]LnCl2, with the smaller elements, Ln = Er (4), Yb (5). The synthesis of a monomeric iodide analogue, [Zr2(OiPr)9]TmI2, 6, by reduction of Zr2(OiPr)8(iPrOH)2 with TmI2(DME)3 is also reported. In all of these complexes, the [Zr2(OiPr)9]- subunit is tetradentate. 1-6 are compared with related cyclopentadienyl halide complexes to evaluate the special features of the dizirconium nonaisopropoxide ligand versus cyclopentadienide.

Journal Article↗
PubMed2000

Effect of prenatal glucocorticoid on fetal lung ultrastructural maturation in hyt/hyt mice with primary hypothyroidism.

Glucocorticoids (GC) and thyroid hormones (TH) accelerate fetal lung maturation. Though GC are used clinically, the mechanisms of GC-induced fetal lung maturity remain unclear. Prenatal GC increase fetal TH activity in humans and in animals. Thus, it is possible that increased fetal TH activity after prenatal GC plays a role in accelerating fetal lung maturation. However, this hypothesis has remained untested due to the lack of a suitable animal model. In the hyt/hyt mouse primary hypothyroidism occurs due to a point mutation in the beta subunit of the thyroid-stimulating hormone receptor of the thyroid gland, and it is transmitted in an autosomal recessive manner. We studied the effect of maternal betamethasone on fetal lung ultrastructure in hyt/hyt (hypothyroid) and Balb-c (euthyroid) mice. Hypothyroid mice were made euthyroid by T3 supplementation and mated to carry hypothyroid pups. Vehicle (n = 6) or betamethasone (n = 6) was injected intraperitoneally twice daily into the doe on days 16 and 17 of gestation. Fetal lungs on 18 days of gestation were subjected to ultrastructural morphometric analysis. The number of lamellar bodies per type II cell increased after betamethasone in Balb-c (2.10+/-0.31 vs. 3.43+/-0.37) and hyt/hyt (0.77+/-0.28 vs. 3.85+/-0.26) mice. The alveolar-to-parenchymal ratio was less in the vehicle-treated hyt/hyt (0.082+/-0.024) as compared with the vehicle-treated Balb-c (0.30+/-0.05) mice, while prenatal betamethasone increased the alveolar-to-parenchymal ratio in the hyt/hyt (0.227+/-0.034) but not in the Balb-c (0.26+/-0.04) mice. The glycogen-to-nucleus ratio was higher in betamethasone-treated hyt/hyt mice (1.46+/-0.20) when compared to vehicle-treated hyt/hyt (0.89+/-0.14) or Balb-c (1.01+/-0.17) or betamethasone-treated Balb-c (0.81+/-0.13) mice. Though tubular myelin was readily apparent in the airspace lumen of betamethasone-treated Balb-c mice, it was absent in betamethasone-treated hyt/hyt fetal lungs. We conclude that fetal thyroid plays an important role in accelerating some aspects of fetal lung ultrastructural maturation from GC stimulation.

Animals↗
PubMed2000

Relative efficacy of insecticide treated mosquito nets (Diptera: Culicidae) under field conditions.

The relative efficacy of insecticide treated mosquito nets was evaluated under field conditions in Dehra village of Dhaulana PHC, District Ghaziabad, U.P., India, during 1996. Nylon nets were impregnated with deltamethrin, cyfluthrin, lambdacyhalothrin, and etofenprox at 25 mg/m2 by standard methods. Repellent, excito-repellency, killing, and airborne actions were monitored from dusk to dawn by hourly collection of mosquitoes that entered and rested in rooms and also females that landed on treated and untreated mosquito nets. Results revealed 15.3-22.9% repellent action, 98.3-99.3% excito-repellency action, and 100% mortality of females that landed on treated fabrics. No significant differences were observed in the efficacy of different synthetic pyrethroids against anophelines. However, against Culex quinquefasciatus Say there was a significant difference between deltamethrin and etofenprox. Control of anophelines was more pronounced than Cx. quinquefasciatus. There was no pronounced airborne action with any insecticide tested. Synthetic pyrethroids with strong airborne action may be more appropriate for impregnation of mosquito nets.

Animals↗