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Background:After the decades of Dichlorodiphenyltrichloroethane (DDT) use, Phlebotomus argentipesreportedly developed resistance against it affecting every aspect of vector control at grass-root level. Although DDT based Indoor Residual Spray (IRS) has been replaced with Alphacypermethrine-a Synthetic Pyrethroid (SP) based insecticide, since 2016 butits successful implementation at the Visceral Leishmaniasis (VL) endemic regime of Bihar doesn’t cause much effect upon VL vector density. Furthermore, the outcomes of existing operational research works, it Original ResearchArticle had been observed that VL vectors are continuously changing its behavior under the pressure of insecticides. Methods: For validating the hypothesis, present study has been carried out at Vaishali and Patna being highly and semi-endemic sites respectively for quantifying the oriental behavior among VL vectors persuaded by the IRS and enforce them to remain alive and get trapped in light trap even after changed chemical composition of IRS i.e., SP-IRS from routine DDT-IRS. Results:Following results, a significant reduction in sand fly density (i.e., 33.09% and 29.16%) was observed for outdoor and indoor caught sand flies, collected with light trap and aspirator respectively. Significant higher no. of sand fly collection in terms of per light traps per night was recorded from the outdoor sites than thosefrom indoor habitat for each village of Vaishali and Saran district of Bihar. Higher no. of male sand flies than to that of female ones were collected from outdoor sites and only unfed female sand flies (i.e., 100%) were caught following SP-IRS from each study villages of Vaishali and Saran districts of Bihar.Conclusions:The results of higher no. of sand flies collection from the outdoor sites as compared with the indoor habitat validate the hypothesis of gradual shifting of habitat of VL vectors from endophilic to exophilic which is undoubtedly followed due to the fact of developed resistance among them against chemical constituent of IRS. Results provide very useful information about the sand fly dynamics under the impact of IRS and accordingly, advocates the combined approach of IRS along with insecticidal fogging together at a same time that could be an effective dividend for maximum VL vector control along for negotiating VL cases at par for longer duration during the maintenance phase at the VL foci.
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ABSTRACT Contact with the pesticide dichlorodiphenyltrichloroethane (p,p′-DDT) can be the cause of various harmful effects in humans, wildlife, and the environment. This pesticide is known to be persistent, lipophilic, resistant to degradation, and bioaccumulive in the environment and to be slowly released into bloodstream. Growing evidence shows that exposure to DDT is linked to type 2 diabetes mellitus. Individuals exposed to elevated levels of DDT and its metabolite have an increased prevalence of diabetes and insulin resistance. To evaluate these possible relationships, experiments were performed on eight-week-old female mice, divided into three groups (n = 10 per group): Group 1 received a vehicle-control intraperitoneal (i.p.) injection of sesame oil; Groups 2 and 3 received an i.p. dose of 50 and 100 µg/g p,p′-DDT respectively, dissolved in sesame oil. All groups were treated once daily for four days. Real-time PCR analysis of several genes was undertaken. Additionally, biochemical parameters and histopathological changes were measured. NQO1, HMOX1, NR1I3 and NR3C1 were up-regulated in DDT-exposed animals compared to the vehicle control group, while only SREBP1 was down-regulated in the 100 µg/g group. MTTP and FABP5, not previously reported for DDT exposure, but involved in regulation of fatty acid fluxes, could also function as biomarkers cross-talking between these signaling pathways. These results suggest that beyond epidemiological data, there is increasing molecular evidence that DDT may mimic different processes involved in diabetes and insulin resistance pathways.
RESUMO O contato com o praguicida diclorodifeniltricloroetano (p, p'-DDT) pode ser a causa de vários efeitos nocivos sobre os seres humanos, animais silvestres e o meio ambiente. Sabe-se de sua característica de bioacumulação, ser altamente persistente no meio ambiente, lipofílico, resistente à degradação e lentamente liberado na corrente sanguínea. Existe uma evidência crescente de que a exposição ao DDT pode ser ligada a Diabetes mellitus tipo 2. Os indivíduos expostos a níveis elevados de DDT e seu metabólito apresentam maior prevalência de diabetes e resistência à insulina. A fim de obter informações sobre essas possíveis relações, camundongos fêmeas de oito semanas de idade foram divididos em três grupos (n = 10 por grupo): Grupo 1 recebeu um veículo de óleo de gergelim via i.p.; os Grupos 2 e 3 receberam, via i.p., 50 e 100 µg/g de p, p'-DDT, respectivamente, dissolvidos em óleo de gergelim. Todos os grupos foram tratados uma vez ao dia durante quatro dias. Além da análise de PCR em Tempo Real de vários genes, os parâmetros bioquímicos e alterações histopatológicas também foram medidos. A expressão gênica do mRNA dos genes NQO1, HMOX1, NR1I3 e NR3C1 foi maior nos animais expostos ao DDT, em comparação ao grupo controle, enquanto a expressão gênica do SREBP1 diminuiu na concentração de 100 µg/g. Os genes MTTP e FABP5 envolvidos na regulação do fluxo de ácidos graxos, embora não estudados quanto à exposição ao DDT, também podem funcionar como biomarcadores de resposta cruzada entre essas vias de sinalização. Esses resultados sugerem que, além de dados epidemiológicos, há cada vez mais evidências moleculares de que o DDT poderia, de fato, imitar diferentes processos que envolvem as rotas de diabetes e de resistência à insulina.
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Mice , Rats , DDT/adverse effects , Liver , Pesticides/analysis , Organic Pollutants , Diabetes Mellitus, Type 2 , InsulinABSTRACT
OBJECTIVE To investigate the effect and mechanism of low concentrations of p,p′-dichlorodiphenyltrichloroethane (p,p′-DDT) on colorectal adenocarcinoma SW620 cell proliferation and apoptosis. METHODS SW620 cells were exposed to low concentrations of p, p′-DDT ranging from 1×10-12 to 1×10-6 mol.L-1 for 48 and 96 h. MTT assay was employed to examine the effect of p,p′-DDT on SW620 cell viability. Different cell stages of cycle and apoptosis rate were determined by flow cytometry after SW620 cells were exposed to 1×10-10 , 1×10-9 and 1×10-8 mol.L-1 for 96 h. Western blotting was used to determine the protein expression of Wnt/ β-catenin signaling components 〔β-catenin, phospho-β-catenin and phospho-glycogen synthase kinase ( GSK) 3β〕, their downstream target proteins ( c-Myc and cyclin D1)and apoptosis related proteins (Bcl-2, Bax, procaspase 8 and procaspase 3). RESULTS The viability of colorectal adenocarcinoma SW620 cells was significantly increased after exposure to low concentrations of p,p′-DDT ranging from 1×10-12 to 1×10-7 mol.L-1 for 96 h. p,p′-DDT 1×10-10 , 1×10-9 and 1×10-8 mol.L-1 exposure led to a decreased percentage of SW620 cells in G1 stage(P<0.01) along with an increased percentage of cells in S stage(P<0.01). Meanwhile, the apoptosis rate was signifi-cantly decreased compared with control group ( P < 0. 01). Exposure to p, p′-DDT from 1 × 10-10 to 1×10-8 mol.L-1 induced upregulation of phospho-GSK3β ( Ser9), β-catenin, c-Myc and cyclin D1 in SW620 cells( P <0.01). Moreover, apoptosis related proteins Bcl-2, procaspase 8 and procaspase 3 were unregulated(P<0.01), and Bax level and caspase 3 activity were decreased in p,p′-DDT-stimulated cells(P < 0.01). CONCLUSION Low concentrations of p, p′-DDT exposure activates Wnt/ β-catenin signaling and affects apoptosis-related proteins, which may be involved in p,p′-DDT-induced cell prolifer-ation as well as suppression of cell apoptosis in SW620 cells.
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La malaria continúa siendo un problema de salud pública mundial. Durante los siglos XX y XXI el abordaje de esta enfermedad sufrió cambios paradigmáticos muy interesantes, pero principalmente estuvo influenciado por los descubrimientos relacionados con la segunda guerra mundial, la situación económica mundial, el advenimiento de nuevas estrategias de control y el abordaje de la enfermedad por medio de la participación comunitaria y el sector de la salud. El propósito de este trabajo es presentar los cambios de paradigmas desde una óptica vertical o erradicación, a una horizontal o eliminación, y desde lo positivista cuantitativo a lo mixto, en el abordaje de la malaria en Guatemala. Se realiza una reseña histórica de la malaria y se discuten los aspectos bioéticos del uso del insecticida dicloro-difenil-tricloroetano a nivel mundial. En los países desarrollados fueron justificadas las intervenciones de erradicación con el rociamiento intradomiciliar del insecticida citado y completarlas con el diagnóstico y tratamiento de la malaria; la realidad en la mayoría de los países en vías de desarrollo, fue diferente, puesto que no pudieron mantener los programas de erradicación por problemas financieros, un ejemplo claro de iniquidad global. Guatemala en esta década trabaja en la fase de preeliminación-eliminación, con buenos resultados, lo que marca un cambio de paradigma e indica que las medidas contra la malaria deben ser horizontales y favorecer el trabajo intra e intersectorial.
Malaria remains a world health problem. During the 20th and 21st centuries, the approach to this disease underwent very interesting paradigmatic changes, but they were influenced by breakthroughs derived from the Second World Wear, the international economic situations, the advent of new monitoring strategies and the approach to the disease based on the community and the health sector involvement. The objective of this paper was to present changes in paradigms form a vertical perspective or eradication to a horizontal viewpoint or elimination, and from a quantitative positivist to a combined standpoint in addressing malaria in Guatemala. A historical account of malaria was made and the bioethical aspects of the use of dichlorodiphenyltrichloroethane worldwide were discussed. The eradicating interventions by using the insecticidal spraying of houses were backed up in the developed countries. This was supplemented with the diagnosis and treatment of malaria. However, the situation was different in most of the developing countries, since their financial restrictions did not make possible to keep the eradication programs, being a clear example of the global inequality. In the present decade, Guatemala is going through the pre-elimination-elimination phase and it works with good results, which is indicative of a change in paradigm and shows that actions against malaria should be horizontal in order to encourage the intrasectorial and the intersectorial work.
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Objective To evaluate the serum organochlorine pesticides residues levels in breast cancer pa-tients with different estrogen receptor(ER). Methods 93 patients of breast cancer from Fengnan districtand 65 pa-tients from Tanghai county in Tangshan were selected,whose ER were detected by pathology and serum organochlo-fine pesticides (DDTs and HCHs) levels were detected and compared with gas chromatography/electron capture. Results The orders of detection rate of HCH isomer in breast cancer patients in two areas were β-HCH >δ-HCH > α-HCH >γ-HCH. The orders of detection rate of DDT isomer in breast cancer patients in two areas were PP'-DDE > PP'-DDT > OP'-DDT > PP'-DDD. The serum levels of β-HCH, PP'-DDE in breast cancer patients in two are-as were positively correlated with age (r=0.272 ,0.330 , P<0.01) or BMI (r=0.312,0.187, P <0.01, <0.05). There were statistical differences in the serum β-HCH,δ-HCH,PP'-DDE levels between the estrogen receptor posi-tive breast cancer patients and the estrogen receptor negative breast cancer patients in two areas (P<0.05 for each). Conclusion The serum organochlorine pesticides residues levels in breast cancer patients with positive es-trogen receptor are higher than that with negative estrogen receptor, implicating that breast cancer is dependent on es-trogen. The cause of breast cancer is likely due to estrogen-like effect of serum organochlorine pesticides residues.
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Objective To analyze the characteristics of of organochlorine pesticides(OCPs) residues in the soil of the suburbs of Guangzhou.Methods In Baiyun,Conghua,Zengcheng,Panyu,Nansha,surface soil(0-20 cm) samples of vegetable fields,orchard and paddy soil were collected,soil profile(20-40cm,40-60cm) of Baiyun and Panyu were also collected,in Aug,2008.Gas chromatography-electron capture detector method(GC-ECD)was used to determine 17 kinds of organochlorine pesticides.Results The detection rate of 17 kinds of organochlorine pesticides was 90.59% in topsoil,the residue level was 4.19-39.89 ng/g,and the detection rate in profiles soil was 76.70 %,the residue level was 2.35-91.26 ng/g.OCPs residues were mainly HCHs and DDTs.Conclusion Detection rate of organochlorine pesticides is high in soil in the investigated soil and in the 20-40 cm profiles of Baiyun and Panyu,the level of OCPs exceeds the related standard limit,which may have adverse effects on soil environment.