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@#Epigallocatechin-3-gallate (EGCG) is a naturally derived compound from green tea with high antioxidant activity and various anti-cancer properties. EGCG has been widely investigated worldwide. However, effects of EGCG on cell cycle of K562 have not been clearly stated elsewhere. This study was conducted with the aim to investigate the antiproliferative effect of EGCG on K562 human leukemic cells and its underlying mechanism of action on the cells. MTT assay was conducted to determine cytotoxicity effect of EGCG on the K562 cells. Meanwhile, cell cycle analysis and DNA damage on the cells were determined by Flow cytometry and Comet assay respectively. K562 cells were treated with EGCG at concentrations ranging from 0 to 100µg/ml for 48 hours. The results showed that EGCG effectively decreased the percentage of cell viability in a dose dependent manner. The IC10, IC25 and IC50 of EGCG on K562 cell lines were 5 ± 2.44 µg/mL, 10 ± 5.93 µg/mL and 50 ± 1.93 µg/mL, respectively. In cell cycle assay, EGCG has shown no significant effect (p>0.05) on the cell cycle of K562 cell line as compared to negative control, whereas Imatinib mesylate as the positive control showed cell cycle arrest at S phase in this cell line. Hence, EGCG can be verified as a non-cell cycle specific compound. In addition, EGCG was found to cause a significant increase (p<0.05) in tail moment value and percentage of DNA tail in K562 cell line, suggesting DNA damage as an early signal of EGCG induced cell cytotoxicity. In conclusion, by decreasing the cell viability and inducing DNA damage, EGCG showed promising potential as an alternative treatment for leukemia through non-cell cycle specific pathway and further investigation on other mechanisms of action of EGCG on the cells is recommended.
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@#Studies on the potential effect of EMF exposure on permeability of the blood-brain barrier (BBB) in humans are virtually absent. This study was conducted to study the effect of EMF exposure on pericytes in brain tissues and its effect on oxidative stress level in the blood through total protein and malondialdehyde (MDA). About 16 male rats (Wistar) were used and divided into two groups which were negative control and treatment group. In negative control group, the animals were placed in a solenoid without any EMF exposure for 3 hours daily for 5 days. In the treatment group, the animals were placed in a solenoid with 0.3 mT EMF exposure for the same time duration. On day 3 and day 5, animals were sacrificed and the brain was removed for histological examination while on day 1, day 3 and day 5, the blood was collected for biochemistry analysis. Histological observation showed the presence of morphological changes in the brain tissues of rats that exposed to EMF. Statistical analysis showed that there is no significant decrease in total protein (p>0.05) between negative control group and treatment group. Meanwhile, MDA level in blood showed a significant increase in treatment group (p<0.05) as compared to the negative control group. The result obtained in this study, suggest that the exposure to EMF can cause changes to the morphology of pericytes in brain tissues, and can increase the MDA level in blood of rats.
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Aims@#To evaluate the anti-leptospiral activity of Canarium odontophyllum leaves against Leptospira interrogans serovar Bataviae and Leptospira borgpetersenii serovar Javanica. @*Methodology and results@#The extracts (hexane, acetone, methanol and aqueous) used in this study were tested at concentration ranging from 0.049 mg/mL to 25 mg/mL using broth microdilution method. Percentage inhibition (%) was obtained through OD reading at 400 nm. Only methanol extract was incubated with Leptospira to observe population changes under dark field microscope prior to subjected for DNA damaging studies through gel electrophoresis of genomic DNA. Methanol extract showed the highest percentage inhibition of 66% against L.interrogans serovar Bataviae and 74% against L. borgpetersenii serovar Javanica. The IC50 value of methanol extract was 4.60 mg/mL and 2.25 mg/mL against serovar Bataviae and serovar Javanica, respectively. Both Leptospira culture which was treated with IC50 value of methanol extract showed drastic decrease in population compared to untreated Leptospira for both serovar. There was no DNA damage towards serovar Bataviae. However, serovar Javanica exhibited DNA damage as observed from the presence of DNA fragmentation on the gel electrophoresis. @*Conclusion, significance and impact of study@#These findings confirmed that methanol leaves extract from of Canarium odontophyllum has a potential to control leptospirosis.
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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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@#Pesticide exposure may cause genotoxic effects by inducing the formation of micronucleus (Mn). Mn are fragments of chromosomes that remains after cells division. The increase in Mn may increase the risk of cancer formation. Our study aimed to determine the effects of lifestyle and pesticide exposure on the formation of Mn in epithelial cells buccal swabs among paddy farmers in Malaysia. About 40 farmers who were exposed to pesticides were chosen as subjects and 30 personnels were possibly not directly exposed to pesticides, were chosen as the control group. Demographic and anthropometric data were obtained from questionnaires developed. Analysis of Mn formation was done using Giemsa staining (10% v/v) and the frequency of Mn formation was scored from 1000 cells per sample. Kruskal-Wallis test done between Mn frequency with age class showed a significant increase (p < 0.05) in Mn frequency as compared to the control in the age group of 30-39 , 40-49 years, and 50-59 years. Significant increased (p < 0.05) were observed between Mn frequency groups of normal BMI, preobese, and grade 1 obese as compared to control. Significant increase of Mn frequency (p < 0.01) was also seen among smokers and farmer’s group (15:39 ± 3.34) as compared to controls (4.76 ± 1.26). The maximum numbers of Mn found in farmers are 7 Mn per cell whereas for control group is only 3 Mn. However, most farmers had only 1 Mn (81.75 ± 6.42%) and 2 Mn (15:28 ± 5.14%). Mn frequency with the duration of exposure to pesticides in a month and the use of PPE revealed no significant difference (p = 0.27). In conclusion, the increased frequency of Mn was influenced by age, gender and BMI of farmers besides commonly repeated duration of exposures and the use of PPE are needed to be studied to analyze the causes of an increased in Mn among farmers.
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Background: Zerumbone (ZER) is a major bioactive compound of Zingiber zerumbet,a wild ginger plant that has been documented to have anti-proliferative, anti-inflammatory andanti-oxidant properties. To investigate its hepatoprotective potential, this study was designed todetermine the treatment effects of ZER on acute hepatotoxicity induced by paracetamol (PCM) inrats.Methods: The control group was administered with phosphate buffer solution (PBS) whilethe other two groups received PCM alone (1000 mg/kg) and PCM + 25 mg/kg ZER, respectively,at 0 h and 4 h after PCM injection. After 24 h, the blood and liver were collected for differentialwhite blood cell count, liver histological observation and biochemical analysis including alanineaminotransferase (ALT), aspartate aminotransferase (AST), and total protein concentration inserum and liver.Results: Treatment with ZER was found to significantly reduce ALT (P = 0.041), AST (P =0.044) and total hepatic protein (P = 0.045) in comparison to PCM-induced rats. Rats treated withZER exhibited the normal structure of hepatocytes with no vacuolisation or necrosis and showedsignificantly reduced neutrophil count (P = 0.037). This finding suggests its ability to suppress theinflammatory processes caused by PCM overdosage and decrease the hepatocytes tendency to gothrough necrotic processes.Conclusion: ZER possessed protective activity against PCM-induced acute hepatotoxicityin a rat model.
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The emergence of research about the biological effects of electromagnetic field (EMF) have growing concern among researchers. The aim of this study was to investigate the effects on the brain of rats periodically exposed to 0.1 mT EMF. Total 24 adult male Sprague Dawley rats were subdivided randomly to 4 groups: 2 control groups (C1 6 hours: 6 h/ day for 5 days; C2 20 hours: 20 h/day for 5 days) and 2 treatment groups which exposed to 0.1 mT EMF (T1 6 hours: 6 h/day for 5 days; T2 20 hours: 20 h/day for 5 days). A significant decrease in the pyramidal cell number was higher as the exposure duration to EMF was extended (T1, p<0.05; T2, p<0.001). The total numbers of pyramidal cells for T1 was 15.18 % lower than of the total found in C1; and in concurring to the pattern, the number of pyramidal cells in T2 was 33.54 % lower than the total in C2. Similarly, there was a significant decrease of the Purkinje cell number as the duration exposure to EMF, extended (T1, p<0.05; T2, p<0.001). The total numbers of Purkinje cells for T1 was 11.20 % lower than C1, in T2 was 16.19 % lower than in C2. There were significant differences between the thickness of granular layer and molecular layer in the control groups and treatment groups. We also report a significant difference in the levels of norepinephrine in T2, 10.71 % higher than C2. Cumulatively, these results suggested that exposure to EMF can exert negative effect on rats brains.
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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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Cytotoxicity of organotin (IV) compounds towards various types of cancerous cells have been extensively studied by researchers worldwide. In this study,two new organotin (IV) compounds; diphenyltin (IV) ethylphenyldithiocarbamate (DFEF) and diphenyltin (IV) butylphenyldithiocarbamate (DFBF) were used to evaluate their cytotoxic effect against erythroleukemia cells, K562. K562 cell was used as target cell whereas Chang liver and V79 fibroblast cells were used to evaluate the effects of both compounds on non-cancerous cells. The cytotoxic effects of both compounds were assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay at 24, 48 and 72 hours using different concentrations. Observations on the morphological changes were carried out with IC50 value for times of exposure similar to the MTT assay test. The cytotoxicity test showed that, DFEF and DFBF compounds were very toxic toward K562 cells with the IC50 values obtained less than 10 μM at all times of exposure. The selectivity index have proven that both compounds exhibited selective cytotoxic effect against K562 cells at 48 and 72 hours, meanwhile at 24 hours, these compounds showed general toxicity towards K562 and non-cancerous cells. We found that both compounds were toxic to non-cancerous cells, Chang liver and V79 cells where the IC50 values were less than 5 μM. Both compounds also showed selectivity to target cell at 48 and 72 hours of exposure. However for 24 hours, these compounds showed general toxicity and non-selective cytotoxic effect towards K562 cells and non-cancerous cells. The morphological changes match with characteristic of apoptosis such as cell shrinkage and formation of apoptotic bodies, also necrosis such as lysis of cells. In conclusion, diphenyltin (IV) alkylphenyldithiocarbamate showed great potential to be a good anti-leukemic agent. However, its specific mechanism of action in K562 cells should be further studied to elucidate its potential as a new anticancer drug