Fixatives Increase the Efficacy of Gel Formulations containing Piper aduncum Linnaeus (Piperales: Piperaceae) Essential Oil as Repellent / Jurnal Sains Kesihatan Malaysia

@#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.

Cytogenetic Analysis Of Buccal Cells From Farmers In Tanjung Karang And Kelantan Who Were Exposed To Pesticides / Jurnal Sains Kesihatan Malaysia

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.

Comparative fly species composition on indoor and outdoor forensic cases in Malaysia.

Forensic entomology refers to the science of collection and analysis of insect evidence in order to determine the minimum time period since death. This study aimed to investigate the occurrence of forensically important flies on 34 human remains referred to Universiti Kebangsaan Malaysia Medical Centre over a period of three years. Entomological specimens were collected at the death scenes and/or during autopsies. Live specimens were reared into adults while preserved specimens were processed for species identification. Five families, seven genera and nine species of flies were identified from human remains. The results of the study showed Chrysomya megacephala (Calliphoridae) maggots occurred on corpses with the highest frequency (70.6%), followed by Ch. rufifacies (Calliphoridae) (44.1%), sarcophagid fly (Sarcophagidae) (38.2%), Synthesiomya nudiseta (Muscidae) (20.6%), Megaselia scalaris (Phoridae) (14.7%), Lucilia cuprina (Calliphoridae) (5.9%), Ch. nigripes (Calliphoridae) (5.9%), Eristalis spp. (Syrphidae) (5.9%) and Hydrotaea spinigera (Muscidae) (2.9%). The greatest fly diversity occurred on remains recovered indoors (eight species) compared to outdoors (three species). Whilst, single and double infestations were common for both indoor and outdoor cases, multiple infestation of up to six species was observed in one of the indoor cases. Although large numbers of fly species were found on human remains, the predominant species were still those of Chrysomya, while S. nudiseta was found only on human remains recovered from indoors. The present study provides additional knowledge in the context of Malaysian forensic entomology and the distribution of forensically important flies which is of relevance to forensic science.

The Effectiveness of Diphenyltin(IV) and Triphenyltin(IV) Alkylphenyldithiocarbamate Compounds as Insecticide Against Aedes aegypti LINN.(Diptera: Culicidae) in Laboratory / Jurnal Sains Kesihatan Malaysia

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

Selenium, Zinc and Chromium Level Among Paddy Farmers Exposed to Pesticide in MADA, Perlis and Fisherman Community in Mersing, Johor / Jurnal Sains Kesihatan Malaysia

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

The COMBI Approach in Managing Dengue Cases in an Urban Residential Area, Nilai, Malaysia

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.

Acute and subacute oral toxicity of Litsea elliptica Blume essential oil in rats.

Litsea elliptica Blume has been traditionally used to treat headache, fever, and stomach ulcer, and has also been used as an insect repellent. The acute and subacute toxicities of L. elliptica essential oil were evaluated orally by gavage in female Sprague-Dawley rats. For the acute toxicity study, L. elliptica essential oil was administered in doses from 500 to 4000 mg/kg (single dose), and in the subacute toxicity test, the following doses were used: 125, 250, and 500 mg/kg, for 28 consecutive days. In the acute toxicity study, L. elliptica essential oil caused dose-dependent adverse behaviours and mortality. The median lethal dose value was 3488.86 mg/kg and the acute non-observed-adversed-effect level value was found to be 500 mg/kg. The subacute toxicity study of L. elliptica essential oil did not reveal alterations in body weight, and food and water consumptions. The haematological and biochemical analyses did not show significant differences between control and treated groups in most of the parameters examined, except for the hemoglobin, mean cell hemoglobin concentration, mean cell volume, mean cell hemoglobin, serum albumin, and serum sodium. However, these differences were still within the normal range. No abnormalities or histopathological changes were observed in the liver, pancreatic islet of Langerhans, and renal glomerulous and tubular cells of all treated groups. In conclusion, L. elliptica essential oil can be classified in the U group, which is defined as a group unlikely to present an acute hazard according to World Health Organization (WHO) classification.

The effect of Piper aduncum Linn. (Family: Piperaceae) essential oil as aerosol spray against Aedes aegypti (L.) and Aedes albopictus Skuse

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.

Toxic effects of Litsea elliptica Blume essential oil on red blood cells of Sprague-Dawley rats.

Litsea elliptica Blume leaves have been traditionally used as medicinal herbs because of its antimutagenicity, chemopreventative and insecticidal properties. In this study, the toxic effects of L. elliptica essential oil against Sprague-Dawley rat's red blood cells (RBCs) were evaluated. L. elliptica essential oil was given by oral gavage 5 times per week for 3 treated groups in the doses of 125, 250, and 500 mg/(kg body weight), respectively, and the control group received distilled water. Full blood count, RBC osmotic fragility, RBC morphological changes, and RBC membrane lipid were analyzed 28 d after the treatment. Although L. elliptica essential oil administration had significantly different effects on hemoglobin (Hb), mean cell hemoglobin concentration (MCHC), mean cell volume (MCV), and mean cell hemoglobin (MCH) in the experimental groups as compared to the control group (P<0.05), the values were still within the normal range. L. elliptica induced morphological changes of RBC into the form of echinocyte. The percentage of echinocyte increased significantly among the treated groups in a dose-response manner (P<0.001). The concentrations of RBC membrane phospholipids and cholesterol of all treated groups were significantly lower than those of control group (P<0.001). However, the RBC membrane osmotic fragility and total proteins of RBC membrane findings did not differ significantly between control and treated groups (P>0.05). It is concluded that structural changes in the RBC membrane due to L. elliptica essential oil administration did not cause severe membrane damage.

A Preliminary Study of Blastocystis hominis in Some Development Areas in Alor Gajah District Melaka / Jurnal Sains Kesihatan Malaysia

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%.