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@#Piper aduncum essential oil exhibit repellency activity and has a potential to be use as an alternative for synthetic repellent such as N,N-diethyl-3- methylbenzamide, (DEET). However, the volatility properties of the essential oil decrease their persistence as a topical repellent. Study has shown that formulation of the essential oil with some fixatives may increase their effectiveness. Therefore, this study was conduct to evaluate the effectiveness of gel formulation containing P. aduncum essential oil with two fixative; vanillin and paraffin oil. Gel formulations containing P. aduncum essential oil with 5% and 10% vanillin and 6% paraffin oil was prepared and tested against Aedes aegypti in laboratory using Standards and Industrial Research Institute of Malaysia (SIRIM) bioassay method. After 240 minute post-application, formulation containing 5% and 10% vanillin was able to provide >70% repellency percentage against mosquito while formulation containing 6% paraffin oil gives <30% repellency percentage. As conclusion, P. aduncum based repellent gel containing 5% and 10% vanillin was able to prolong the effect of P. aduncum essential oil as repellent against dengue vector in laboratory.
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Pesticides and chemical fertilizers are widely used in agriculture to increase crop productivity among farmers.However, exposure to pesticides will give potential risk to human health. The aim of this study was to analyze thefrequency of micronucleus (MN) and binucleus (BNu) formation in buccal cells from farmers who were exposedto pesticides using the MN assay. Buccal swabs were collected from the farmers in Tanjung Karang (n = 32) andKelantan (n = 43) using wooden tongue depressor. A structured questionnaire was used to obtain demographic dataof the farmers. Cytogenetic analysis was carried out by Acridin Orange (AO) staining 0.0025% (w/v). The frequencyof MN and BNu as the biomarkers for cytogenetic damage was observed by using a fluorescence microscope.Comparison of frequency of MN and BNu is conducted in two areas namely Tanjung Karang, Selangor and Kelantanbecause of the agricultural activity and the type of pesticides used are different. Results showed that the frequencies of bothMN and BNu among farmers in Tanjung Karang were significantly higher (p 0.05) and the practices of PPE (Personal Protective Equipment) (p > 0.05). This may suggeststhat cytogenetic changes were not influenced by these factors. In addition, correlation study shows positive correlationbetween the frequency of MN with the pesticide exposure of farmers in Tanjung Karang (p > 0.05, r = 0.015) and Kelantan(p > 0.05, r = 0.0158). Besides, the frequency of BNu also has a positive correlation with the pesticide exposure amongfarmers in Tanjung Karang (p > 0.05, r = 0.036) and farmers in Kelantan (p > 0.05, r = 0.013). Hence, this present study demonstrated that exposure to pesticides increasedthe formation of MN and BNu among farmers and theprolonged use of pesticides may induce genotoxicity andDNA damage to human.
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The development of using insecticide of organotin(IV) compound against Aedes aegypti mosquitoes have been explored and test the effectiveness of compound to prevent resistance insecticide. The aim of this research was to examine the insecticidal effect which is larvisidal and adulticidal effect two series of diphenyltin(IV) and triphenyltin(IV) alkylphenyldithiocarbamate compounds against Ae. aegypti in laboratory. Four compounds which diphenyltin(IV) ethylphenylditiocarbamate (DFEF), triphenyltin(IV) ethylphenylditiocarbamate (TFEF), diphenyltin(IV) butylphenylditiocarbamate (DFBF) and triphenyltin(IV) butylphenylditiocarbamate(DFBF) were carried out larvicidal bioassay testing against third instar larvae of Aedes aegypti. Based on activity of larvicidal testing, further study was continued to compound WHO showed the best activity larvicidal to test adulticide effect against female mosquito adults of Aedes aegypti. The results showed that TFEF compound showed the best larvicidal effect with LC50 and LC90 values of 0.082 ppm and 0.184 ppm, respectively. Therefore, TFBF compound showed a good larvicide effect with LC50 and LC90 values of 0.108 ppm and 0.273 ppm respectively. However, both of two compounds DFEF and DFBF were not a good of larvicide effect. Based on adultisial testing, TFEF compound not showed good activity of adulticidal effect with high LC50 and LC90 values which is 31,556.03 ppm and 98,427.05 ppm respectively. TFEF compound not show the good adulticide effect but it has potential to develop as larvicide. In conclusion, further study was needed to elucidate and ensure this compound will be used safely as larvicide
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Pesticide exposure can lead to low trace elements levels in human body. Trace element plays important role in body metabolism. The aim of this study was to study the levels of selenium, zinc and chromium among paddy farmers who expose to pesticide in Wilayah I, MADA, Perlis. This cross sectional study involved 70 males paddy farmers and 57subjects living in fisherman village as control group who were aged between 21 to 80 years old. Subjects were interviewed to obtain information on their demographic data by using validated questionnaire. Subjects also were examined for their blood pressure and glucose level. Selenium, zinc and chromium levels were analyzed by using acid digestion method and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Results showed that selenium levels in hairs (5.11 ± 17.05 μg/L) and nails (4.92 ± 2.17 μg/L) were significantly (p 0.05) between all trace element levels and duration of pesticide exposures. In conclusion, levels of trace elements were lower in nails and hairs of paddy farmers than fisherman community group
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Dengue is a disease propagated by vectors namely Aedes spp. mosquitoes. One of the effective approaches to control dengue is through integrated vector management and intervention programs. COMBI or Communication for Behavioral Impact is a strategic approach to control the Aedes population as well as dengue cases. This study was conducted at Taman Desa Kolej, Nilai, Negeri Sembilan, an suburban residential area to determine the effectiveness of COMBI, by using questionnaire and entomological survey as well as implementation of an intervention program. We carried out activities such as the establishment of COMBI promoter team, clean up events, talk shows with the residential community and distributed pamphlets containing information about dengue. Results indicated significant difference (p<0.05) on the knowledge, opinion and practices about dengue among the residents, for the pre and post intervention program. The entomological survey showed that, the primary mosquito species in this area was Aedes albopictus which comprised of 78 (31%) of the total mosquitoes examined, followed by Culex gelidus of 58 (23%), Culex quinquefasciatus of 37 (14.7%) and Aedes aegypti of 21 (8.3%). The density of Aedes population did not show any significant difference. In conclusion, COMBI intervention was effective in controlling dengue cases in Taman Desa Kolej.
Subject(s)
Dengue , Aedes , Data Collection , Urban Population , MalaysiaABSTRACT
The bioefficacy of Piper aduncum L. essential oil formulated in aerosol cans was evaluated against Aedes aegypti and Aedes albopictus in a simulated room. The aerosol spray test was based on the Malaysian test standard for aerosol (MS 1221:1991UDC 632.982.2 modified from WHO 2009 methodology) and examined the knockdown effect within 20 minutes of exposure. Mortality rate after 24 hour of holding period was also determined. A commercial aerosol spray (0.09% prallethrin 0.05% d-phenothrin) was also tested as a comparison. Our results showed that the knockdown effect of the commercial aerosol spray and P. aduncum essential oil spray (8% and 10% concentrations) was significantly higher in Ae. albopictus adult females, when compared with that of Ae. aegypti adult females (P<0.05). There was a significant difference in knockdown between commercial aerosol spray and essential oil spray for both Aedes spp. (P<0.05). The essential oil induced significantly higher mortality in Ae. aegypti (80%) than in Ae. albopictus (71.6%) (P<0.05). The commercial aerosol spray caused 97.7% and 86.5% mortality against Ae. aegypti and Ae. albopictus respectively (P<0.05). Based on these data, P. aduncum essential oil has the potential to be used as an aerosol spray against Aedes spp.
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This study investigated the repellency of Piper aduncum essential oil against Ae. aegypti under laboratory conditions, using human volunteers. Optimum repellency (ED₅₀ value 1.236 \µgcm⁻\² and ED₉₀ 0.845 \µgcm⁻\²) occurred at 90 seconds\’ exposure. Exposures of 60 and 120 seconds yielded much higher ED50 values (2.4170 \µgcm⁻\² and 1.8161 \µgcm⁻\², respectively). There was no significant difference between the ED₅₀ value of the essential oil and DEET (P \> 0.05). P. aduncum essential oil on human skin, at a concentration of 0.4 g, showed an immediate 100% reduction in Ae. aegypti mosquito bite, which reduced to 70.03% at hour 8 post-treatment. Treatment with 10% DEET yielded an immediate 100% reduction until hour 4, then reduced to 73.88% at hour 8 post-treatment. There was no significant difference between the plant essential oil and the commercial product DEET (p \> 0.05). Thus, P. aduncum essential oil is a potential repellent against dengue/dengue hemorrhagic fever vectors.
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A descriptive study was conducted to evaluate the prevalence of Blastocystis hominis in children aged between 1-12 years old from randomly selected villages in Alor Gajah district Melaka. The sampling was carried out from 1st to 7th of July of 2006. A total of 48 faecal samples were obtained from the children in those studied villages. The faecal specimens were examined by direct saline wet moun, formalin ethyl acetate concentration and trichrome staining method. It was found that 45.8% (22 out of 48) of the examined children were infected with Blastocystis hominis . Based on the results, the cumulative prevalence of three methods used showed that Blastocystis hominis infection in female children higher compared to male children. Whilst the schooling children aged of 6 to 12 years had a higher prevalence than pre school children at the age of 1-5 years. In term of diagnosis, formalin ethyl acetate concentration method showed prevalence of detection at 60.9%. It was followed by direct saline wet mount (43.5%) and trichrome staining at 34.8%.