Efecto del tipo y del número de lavados en la eficacia de mosquiteros tratados con deltametrina de larga duración para el control de Aedes aegypti en Girardot, Colombia / Effect of the type and number of washes in the efficacy of long lasting insecticidal nets for Aedes aegypti control in Girardot, Colombia

Resumen Introducción. El uso de mosquiteros tratados con insecticida en fórmulas de larga duración ha demostrado resultados prometedores en el control de Aedes aegypti. Objetivo. Evaluar la eficacia de mosquiteros impregnados con deltametrina en una fórmula de larga duración para el control de A. aegypti en Girardot, Colombia, después de tres lavados. Materiales y métodos. Se hicieron bioensayos de eficacia de los mosquiteros contra A. aegypti silvestres después de utilizar los siguientes tres productos de lavado, siguiendo la metodología de la Organización Mundial de la Salud: detergente en polvo, detergente en polvo y blanqueador, y jabón de barra, todos utilizados hasta en 20 lavados. Resultados. El tipo de producto de lavado y el número de lavados afectaron significativamente la eficacia de los mosquiteros impregnados con deltametrina. El lavado con jabón de barra presentó el mayor efecto, pues en tan solo seis lavados la mortalidad bajó a 50 % (25/50), en contraste con 66 % (33/50 de mortalidad después del lavado con detergente en polvo y de 84 % (42/50) después del lavado con detergente y blanqueador. En cuanto al número de lavados, el jabón en barra también causó una mayor reducción de la eficacia: a 68 % con solo tres lavados. Conclusión. La eficacia de los mosquiteros impregnados con deltametrina de larga duración en el control de A. aegypti varió con el tipo de producto de lavado y el número de lavados, siendo el jabón en barra el que redujo su eficacia en mayor medida. Se requieren nuevos estudios para establecer la disminución en la concentración del insecticida entre lavados.

Abstract Introduction: The use of long lasting insecticidal materials has shown promising results in the control of Aedes aegypti. Objective: To evaluate the efficacy of long-lasting insecticidal nets (PermaNet®) for Aedes aegypti control after three washing treatments in the city of Girardot, Colombia. Materials and methods: Standard bioassays were conducted with the nets following the World Health Organization protocols using wild A. aegypti after three washing treatments: (1) Detergent powder, (2)detergent powder and bleach, and (3) bar soap, until completing 20 washes. Results: The type and number of wash treatments had a significant effect on net efficacy. Greater effects in the insecticide bioavailability were seen for the bar soap treatment. After six washes, mortality decreased by 50% (25/50), vs 66% (33/50) for the detergent powder and 84% (42/50) for the detergent powder and bleach treatments. Regarding the number of washes, the bar soap treatment reduced the efficacy to 68% after only three washes. Conclusion: The effectiveness of long-lasting insecticidal nets (PermaNet 2.0) for A. aegypti control varied in relation to the treatment and number of washes. The bar soap treatment resulted in the greatest reduction of mortality. Further studies on insecticidal reductions are needed under local conditions.

Field evaluation of ZeroFly® - an insecticide incorporated plastic sheeting against malaria vectors & its impact on malaria transmission in tribal area of northern Orissa.

Background & objectives: Insecticide incorporated plastic sheeting is a new technology to control mosquitoes in emergency shelter places and also temporary habitations in different locations. Therefore, field studies were conducted to assess the efficacy of ZeroFly® plastic sheeting treated with deltamethrin on prevailing disease vectors Anopheles culicifacies and An. fluviatilis and its impact on malaria transmission in one of the highly endemic areas of Orissa. Methods: The study was conducted in Birkera block of Sundargarh district, Orissa state. The study area comprised 3 villages, which were randomized as ZeroFly plastic sheet, untreated plastic sheet and no sheet area. ZeroFly plastic sheets and untreated plastic sheets were fixed in study and control villages respectively covering all the rooms in each household. Longitudinal studies were conducted on the bioefficacy with the help of cone bioassays, monitoring of the mosquito density through hand catch, floor sheet and exit trap collections and fortnightly domiciliary active surveillance in all the study villages. Results: In ZeroFly plastic sheeting area, there was a significant reduction of 84.7 per cent in the entry rate of total mosquitoes in comparison to pre-intervention phase. There was 56.2 per cent immediate mortality in total mosquitoes in houses with ZeroFly sheeting. The overall feeding success rate of mosquitoes in the trial village was only 12.5 per cent in comparison to 49.7 and 51.1 per cent in villages with untreated plastic sheet and no sheet respectively. There was a significant reduction of 65.0 and 70.5 per cent in malaria incidence in ZeroFly plastic sheeting area as compared to untreated plastic sheet and no sheet area respectively. Interpretation & conclusions: Our study showed that introduction of ZeroFly plastic sheets in a community-based intervention programme is operationally feasible to contain malaria especially in the high transmission difficult areas.

Synthesis of novel tricyclic heterocycles from 2- [3-Methyl - 1,2 dihydroquinoxalin - 2 -ylidene] malononitrile

A number of pyrrolo [1.2-a]quinoxalines [3a-f], pyrimidol [1,6-a]quino-xalines [5a-c. 10.13]. pyrido[1.2-a]quinoxalines [6, 7a.b, 8a.b. 14]. [1.3] thiazino-[3,4-]quinoxalines [9, 11] and [1.3] oxazino [3,4-a]quinoxalines [12a.b] were obtained via interaction of 2-[3-methyl-1.2-dihydrquinoxalin-2-ylidene]malono-nitrile 2 with different reagents

Sintesis de 4-aminoquinolinas promovida por acidos Lewis / Lewis acids mediated synthesis of 4-aminoquinolines

Se logró la síntesis de 4-amino-2-quinolomas a partir de N-fenilcianoacetamidas y de 4-aminoquinolinas a partir de 2-aminobenzonitrilo y compuestos Beta-dicarbonílicos. En ambos casos se utilizaron ácidos Lewis como catalizadores.

Hydrazidoy halides in heterocyclic synthesis: Synthesis of several new polyfunctional pyrazole and 1,2,4-Triazole derivatives via dipolar cycloduction reactions on the corresponding nitrile imines

The nitrile imine generated by the action of triethylamine on 2-bromo-1-benzofurylglyoxal-2-[3 phenylpyrazol 5-yl]-hydrazone reacted with some Schiff bases, -nitrostyrenes and thiocarboxamidocinnamonitrile derivatives via dipolar cycloaddition reactions to yield several new polyfunctional pyrazole and 1,2,4-triazole derivatives. Structures were confirmed by elemental analysis and spectral data studies

Hydrazidoyl halides in heterocyclic synthesis.III+: synthesis of several new pyrazole pyrrolino [3,4-c] pyrazoles and pyrazolo [3,4-d] pyridazine, derivatives via dipolar cycloaddition reactions

A variety of new pyrazole, pyrrolinopyrazole and pyrazolopyridazine derivatives were synthesised via the dipolar cycloaddition reactions of acrylonitrile, ethyl acrylate and N-arylmaleimides with the nitrile imine regenerated from 2-bromo-1- benzofurylglyoxal-2-[3-phenylpyrazol-5-yl]-hydrazone. Structure of the newly synthesized derivatives were established on the basis of elemental analysis and spectral data

Metal chelates of 3-amino-2-substituted crotononitrile

Synthetic heterocyclic organic chemistry involves specially designed reagents which are readily generated and then used to provide molecules built-in functional moieties usually utilized several applications. Important examples of such reagents are Beta-amino crotononitrile which have been proven to be valuable in the synthesis of a wide variety of unique heterocyclic systems such as pharmaceuticals, fungicides and solvatochromatic dyes [1-4]. It is known that metal complexes have greater activity than the coordinating agents themselves [5]. Synthesis and characterization of solid complexes of several transition metal cations were the primary concern of our earlier work [6-15]. However, it seems that no studies have been made on the complexes of compound [I] in the solution phase or in the solid state, which will be investigated in the present study. Conductometric, spectrophotometric measurements are used for characterization of some of these complexes as well as elemental analysis, magnetic measurements and spectral [electronic, IR] studies. The mechanism of the chelation process will also be investigated for each of the different ions used

A study of aggregation of 9-(dicyano-vinyl)julolidine.

Di(cyano vinyl)julolidine (DCVJ) is a fluorescent probe which has been used to monitor the local mobility of its binding sites on proteins. It shows a concentration dependence of its emission spectrum in water. At higher DCVJ concentrations, a longer wavelength band appears. The latter increases relative to the shorter wavelength band as a function of increased DCVJ concentration. Absorption and excitation spectra indicate that the concentration dependent emission in the longer wavelength is a consequence of association in the ground state and subsequent excimer formation. DCVJ forms two types of complexes with gamma-cyclodextrin, one of which shows the longer wavelength emission band. Analysis of stoichiometry of association also suggests that longer wavelength emission band may be a consequence of association of two molecules of DCVJ in the gamma-cyclodextrin cavity. Possible uses of such excimer formation in biological systems have also been discussed.

Synthesis and reactions of 1-cyano-2,2-diphenyl acrylic acid chloride

1 Cyano-2-,2-diphenylaciylic acid chloride [I] reacts with aromatic amines yielding the anilides [2a-d], with anthranilic acid the product 2e was converted to the benzoxazone derivative [3]. Reaction of 1 with hydrazine hydrate and benzoyl hydrazine afforded the diaroyl hydrazines [4] and [2g] which are cyclised to the oxadiazole derivatives [5] and [8] respectively. Cyclisation of 4 in acetic anhydride gave pyrazolidine derivative [6].With phenyl hydrazine 1 gave either the anilide [2f] or the pyrazolidine derivative [7]. In the presence of anhydrous aluminium chloride, 1 was converted to the inden-one [9] and/or the ketone [10 a and b]

Study of the thermal stability and mechanical properties of some styrene-acrylonitrile copolymers

Copolymers of styrene and acrylonitrile were prepared with different compositions and were identified by infrared and nuclear magnetic resonance spectroscopic techniques. The triad sequence distribution of the prepared copolymers .was determined by 13[C-]nmr. Thermogravimetric analysis showed that the thermal stability of the copolymers are increased by increasing the acrylonitrile ratio. The mechanical measureanents showed that the tensile strength increases with the introduction of acrylonitrile groups into the copolymer chains

Reaction of enaminodimidones with x-cyanocinnamonitriles and their ester analogues

The reaction of several N-Substituted enaminodimidones with alpha, B-unsaturated nitriles is described. N-Aryl-enaminodimidones were found to react differently from their N-alkyl analogues giving the quinoline B-enaminotriles [3 a-m] and their esters with the former and the arylideneamine [4 a,b] in case of the latters. Likewise, the reaction products were found to be depending on polarity and temperature. 1[H] nmr, ir and microanalysis were consistent with the chemical structure of the products