BackgroundMosquito repellents and emanators confer protection against mosquito bites through spatial action of emanated vapours which are released into the adjoining environment. Synthetic insecticides released into the environment in ultra low volume vapour phase deter the mosquitoes from biting humans in a protected space.MethodsFormulation patches were prepared using the solvent evaporation method over a backing membrane and using Dibutylphthalate (DBT) as a plasticizer. The effect of formulation variables on the deltamethrin release from the patch matrices were studied under accelerated conditions, whereas, HPLC was used for quantitative estimation of deltamethrin. The prepared patch formulations were subjected to physicochemical studies, such as, deltamethrin content, thickness, weight variation, percent moisture content, moisture uptake, surface area and surface pH determination. Deltamethrin-polymer interaction and compatibility was ascertained using DSC and FT-IR, while surface morphology and deltamethrin distribution in the patch were studied using SEM technique. Repellent activity of the patch formulations was evaluated against Ae. albopictus mosquitoes.ResultsBlends of polymeric combinations of polyvinylpyrrolidone (PVP) and ethyl-cellulose (EC) with admixture of deltamethrin provided prolonged repellent activity against Ae. albopictus mosquitoes. Physicochemical characterisation indicated the suitability of deltamethrin patch formulation with the polymeric combinations of PVP and EC. Patches were very effective against laboratory reared Ae. albopictus mosquitoes. No significant difference was observed between the performance of test patches and commercially available repellent cream Mosqshield®.ConclusionDeltamethrin loaded patches provided effective repellency against Ae. albopictus mosquitoes. The study emphasised that deltamethrin released to the environment in low concentration could be an excellent spatial repellent against hematophagous mosquitoes.

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The loss of permethrin from impregnated uniforms due to repeated washings was studied by chromatographic estimation of the residues. The mean (± SE mean ) percentage losses of permethrin after one to five washings were 16.7 ± 2.3, 22.5 ± 3, 29.6 ± 2.9, 40.2 ± 2 and 52.2 ± 2.4, respectively. The reduction in contact toxicity against mosquitoes after each washing was studied by World Health Organization tube and cone bioassays against Aedes albopictus mosquitoes. The median knockdown time for 5-min exposure to the treated uniforms increased from 5.9 to 71.8 min after five washings. Mosquito mortality 24 h post-exposure in cone bioassays was \80 % after the fifth washing, indicating the loss of efficacy. The uniforms need to be retreated after five washings so as to ensure adequate protection against disease vectors. The washing water should be properly disposed off to prevent environmental contamination and toxicity to aquatic organisms. Methods for treatment of military uniforms, which ensure high resistance to washing, need to be adopted so as to avoid frequent re-impregnations with permethrin.

Background:  Diseases of the cervix are common in women. Detection of neoplastic lesions is of prime importance in the evaluation of cervical smears although their frequency is less than the non-neoplastic conditions. Reactive and inflammatory conditions, however, may mimic or obscure the dysplastic changes. The aim of this study was to evaluate the frequencies of various inflammatory, reactive and neoplastic   lesions in the cervical smears.Materials and Methods: This was a retrospective study of 150 cases of cervical smears collected from medical record section of the hospital and Department of Pathology at National Medical College from April 2013 to April 2015.Results: Of 150 patients who underwent cervical cytology, only 15 cases (10%) had epithelial cell abnormalities. This was followed by reactive cellular changes associated with inflammation (16.7%), infections (5.3%) and atrophy (1.3%). Low grade squamous intraepithelial lesion (6%) was the most common epithelial cell abnormality followed by high grade squamous intraepithelial lesion (2%), atypical glandular cells (1.3%) and squamous cell carcinoma (0.7%).Conclusion: Reactive changes including atrophy were the commonest finding. Squamous intraepithelial lesion was commonest finding among epithelial abnormalities. Glandular intraepithelial lesions and squamous cell carcinoma were also identified. Among infections Trichomoniasis  and candidiasis  were seen.