Larvicidal potential of plant-based extracts against dengue vector: A short review.

INTRODUCTION: Dengue fever, a vector borne disease transmitted primarily by Aedes albopictus and Aedes aegypti mosquitoes, has triggered a significant global resurgence. While many vector control programs depend on the use of chemical insecticides to curb outbreaks, its heavy reliance raises environmental concerns and the risk of insecticide resistance. Alternatively, botanically derived insecticidal agents with larvicidal properties offer an ecofriendlier option. This review aims to analyze scientific reports that described the effectiveness of plant-derived extracts for vector control. MATERIALS AND METHODS: A literature search was performed to analyze studies that focused on plant-based extracts used for larvicidal purposes using databases such as Science Direct. Springer, PubMed, and Scopus. The inclusion criteria for publications were larvicidal effects, published in English from the year 2017 and availability of full-text articles. The available literature was further characterized by the value of larvicidal activities of LC50 and LC90 (< 50 ppm), of 22 different parts of plant species from 7 plant families namely Apiaceae, Asteraceae, Lauraceae, Magnoliaceae, Myrtaceae, Piperaceae and Rubiaceae. RESULTS: When comparing the values of LC50, 12 plants species (Artemisia vulgaris, Crassocephalum crepidioides, Echinops grijsii, Melaleuca leucadendra, Neolitsea ellipsoidea, Pavetta tomentosa, Piper betle, Piper caninum, Piper Montium, Piper muntabile, Piper ovatum, Tarenna asiatica) showed promising larvicidal efficacies with LC50 < 10 ppm. CONCLUSION: This review emphasizes the effective alternatives of plant extracts for the potential production of larvicides. Piper betle extract and chloroform extract of Tarenna asiatica reported the most significant larvicidal activity (LC50 < 1 ppm) against mosquito vectors. Further reviews focusing on the mode of actions of its phytochemically constituents are essential for the future development of potentially significant plant-based larvicides.

Human brucellosis: Six years retrospective study on seropositivity in Malaysia.

INTRODUCTION: Human brucellosis is a zoonotic disease in Malaysia. This study analysed six-year retrospective seropositivity trends of human brucellosis cases from 2014 to 2019. METHODS AND MATERIALS: A total of 1,281 serum samples were obtained from suspected brucellosis patients were included. The sera were tested using an enzyme-linked immunosorbent assay for IgM and IgG antibodies for Brucella spp. Samples with equivocal or positive antibody index were confirmed with an immunocapture agglutination. RESULTS: During the study period, 5.8% (n=74) of suspected cases showed seropositivity for human brucellosis. The central region has the highest seropositivity cases of human brucellosis. Consumption of unpasteurised milk was significantly associated with human brucellosis in this study with adjusted odds ratio ((AOR) = 4.56, 95% CI = 2.6, 8.02, p-value < 0.001). The age group of less than 15 years old was more likely to contract brucellosis ((AOR) = 2.81, 95% CI = 1.01, 7.84 p-value < 0.048). CONCLUSION: Serological tests have been widely used for the diagnosis of human brucellosis. However, diagnosis using serology is often challenging without the presence of a convalescent sample. In conclusion, even though human brucellosis has a low prevalence rate, the disease has serious public health implications. The usage of effective diagnostic tools as well as implementation of 'One Health' approach are the way forward to prevent and control of brucellosis in the country.

The need of a system phantom for quantitative hybrid nuclear imaging of PET/CT: A systematic review.

INTRODUCTION: There has already been a rising demand in utilising phantom for hybrid Positron Emission Tomography/ Computed Tomography (PET/CT) scanner of nuclear imaging. This review further clarifies this topic and investigates how the previous research phantoms operated with the need for quantitative hybrid nuclear imaging of PET/CT while providing a relatively high image quality when it was performed. In this article, the necessity of previous and current phantom studies in hybrid nuclear imaging of PET/CT scanners is reviewed. METHODS: PubMed and Google Scholar were systematically searched for the relevant studies by following the PRISMA 2009 checklist. A past decade literature search was conducted from 2010 until November 2020 to secure the relevance of the phantom study. Databases were recruited using keywords such as phantom, quantification, standardisation, harmonisation, image quality, standardised uptake value and multicentre study. However, all keywords were related to PET/CT. All abstracts and eligible full-text articles were screened independently, and finally, the quality assessments of this review were performed. RESULTS: From the 200 retrieved articles, 80 were rejected after the screening of the abstracts and 35 after reading the full-text. The 20 accepted articles addressed the distribution of phantom types used in selected articles studies which were NEMA (67%), ACR (8%) and others (25%). The articles showed the various experimental studies, either phantom studies (35%) or phantom plus clinical studies (65%). For clinical studies (n = 829), the distribution of prospective studies was (n = 674) and retrospective studies was (n =155). The distribution of phantom pathway application showed the studies focused on 40% of reconstruction protocol studies, 30% of the multicentre and standardisation of accreditation program studies, and 30% of the quantification of uptake values studies. CONCLUSIONS: According to this review, the phantom study have a pivotal role in hybrid nuclear imaging of PET/CT either in technical aspects of the scanners (such as data acquisition and reconstruction protocol) or clinical characteristics of patients. In addition to this, the necessity to identify the suitable system phantoms to use within PET/CT scans by considering the continuous development of new phantom studies are needed. Researchers are encouraged to adopt efforts on phantom quantitative validation, including verification with clinical data of patients.

Trend and pattern of melioidosis seropositivity among suspected patients in Malaysia 2015 - 2019.

Melioidosis is a disease of public health importance associated with high case-fatality rates in animals and humans caused by Burkholderia pseudomallei (B. pseudomallei ), a gram- negative bacterium that lives in tropical soil environments. This study determined the seropositivity for melioidosis among patients admitted to healthcare centres in Malaysia, from 2015 to 2019 and identified factors related to it. A total of 26,665 serum samples of suspected melioidosis patients from Malaysia hospitals were tested for IgM against B. pseudomallei. About 16.4% of total samples were seropositive and majority of them were 55 years old and above. However, younger people aged less than 15 years old were the most susceptible to the infection (AOR 3.04, p <0.001, 95% CI: 2.73, 3.39). Melioidosis infection was the highest in Sarawak (15.1%) while Perlis was the least exposed to the infection (0.9%). Further analyses showed that patients with chronic lung disease (adjusted OR: 4.03, p < 0.001, 95% CI: 2.77, 5.86) were more susceptible to melioidosis infection. In conclusion, although serology testing is not a gold standard test in diagnosing melioidosis, it has been used as a tool in treatment monitoring and disease surveillance among patients and at-risk community in the endemic hot-spots regions.

Trend and pattern of melioidosis seropositivity among suspected patients in Malaysia 2015 – 2019

@#Melioidosis is a disease of public health importance associated with high case-fatality rates in animals and humans caused by Burkholderia pseudomallei (B. pseudomallei), a gramnegative bacterium that lives in tropical soil environments. This study determined the seropositivity for melioidosis among patients admitted to healthcare centres in Malaysia, from 2015 to 2019 and identified factors related to it. A total of 26,665 serum samples of suspected melioidosis patients from Malaysia hospitals were tested for IgM against B. pseudomallei. About 16.4% of total samples were seropositive and majority of them were 55 years old and above. However, younger people aged less than 15 years old were the most susceptible to the infection (AOR 3.04, p <0.001, 95% CI: 2.73, 3.39). Melioidosis infection was the highest in Sarawak (15.1%) while Perlis was the least exposed to the infection (0.9%). Further analyses showed that patients with chronic lung disease (adjusted OR: 4.03, p < 0.001, 95% CI: 2.77, 5.86) were more susceptible to melioidosis infection. In conclusion, although serology testing is not a gold standard test in diagnosing melioidosis, it has been used as a tool in treatment monitoring and disease surveillance among patients and at-risk community in the endemic hot-spots regions.

The cytotoxic effect and glucose uptake modulation of Baeckea frutescens on breast cancer cells.

BACKGROUND: Baeckea frutescens (B. frutescens) of the family Myrtaceae is a plant that has been used in traditional medicine. It is known to have antibacterial, antipyretic and cytoprotective properties. The objective of this study is to explore the mechanism of B. frutescens leaves extracts in eliminating breast cancer cells. METHOD: B. frutescens leaves extracts were prepared using Soxhlet apparatus with solvents of different polarity. The selective cytotoxicity of these extracts at various concentrations (20 to 160 µg/ml) were tested using cell viability assay after 24, 48 and 72 h of treatment. The IC50 value in human breast cancer (MCF-7 and MDA-MB-231) and mammary breast (MCF10A) cell lines were determined. Apoptotic study using AO/PI double staining was performed using fluorescent microscope. The glucose uptake was measured using 2-NBDG, a fluorescent glucose analogue. The phytochemical screening was performed for alkaloids, flavonoids, tannins, triterpenoids, and phenols. RESULTS: B. frutescens leaves extracts showed IC50 value ranging from 10 -127µg/ml in MCF-7 cells after 72 h of treatment. Hexane extract had the lowest IC50 value (10µg/ml), indicating its potent selective cytotoxic activity. Morphology of MCF-7 cells after treatment with B. frutescens extracts exhibited evidence of apoptosis that included membrane blebbing and chromatin condensation. In the glucose uptake assay, B. frutescens extracts suppressed glucose uptake in cancer cells as early as 24 h upon treatment. The inhibition was significantly lower compared to the positive control WZB117 at their respective IC50 value after 72 h incubation. It was also shown that the glucose inhibition is selective towards cancer cells compared to normal cells. The phytochemical analysis of the extract using hexane as the solvent in particular gave similar quantities of tannin, triterpenoids, flavonoid and phenols. Presumably, these metabolites have a synergistic effect in the in vitro testing, producing the potent IC50 value and subsequently cell death. CONCLUSION: This study reports the potent selective cytotoxic effect of B. frutescens leaves hexane extract against MCF-7 cancer cells. B. frutescens extracts selectively suppressed cancer cells glucose uptake and subsequently induced cancer cell death. These findings suggest a new role of B. frutescens in cancer cell metabolism.

The Cytotoxic Properties of Baeckea frutescens Branches Extracts in Eliminating Breast Cancer Cells.

Breast cancer is the leading cause of cancer death in women in over 100 countries worldwide and accounts for almost 1 in 4 cancer cases among women. Baeckea frutescens of the family Myrtaceae has been used in traditional medicine and is known to possess antibacterial, antipyretic, and cytoprotective properties. In this study, we investigated the role of Baeckea frutescens branches extracts against human breast cancer cells. Baeckea frutescens branches extracts were prepared using Soxhlet apparatus with solvents of different polarity. The selective cytotoxic activity and the glucose consumption rate of Baeckea frutescens branches extracts of various concentrations (20 to 160 ug/ml) at 24-, 48-, and 72-hour time points were studied using MTT and glucose uptake assay. The IC50 values in human breast cancer (MCF-7 and MDA-MB-231) and mammary breast (MCF10A) cell lines were determined. Apoptotic study using AO/PI double staining was performed using fluorescent microscopy. The glucose uptake was measured using 2-NBDG, a fluorescent glucose analogue. The phytochemical screening of major secondary metabolites in plants was performed. This study reports that Baeckea frutescens branches extracts showed potent selective cytotoxic activity against MCF-7 cells compared to MDA-MB-231 cells after 72 hours of treatment. Evidence of early apoptosis which includes membrane blebbing and chromatin condensation was observed after 72 hours of treatment with Baeckea frutescens branches extracts. Interestingly, for the glucose uptake assay, the inhibition was observed as early as 24 hours upon treatment. All Baeckea frutescens extracts showed the presence of major secondary metabolites such as tannin, triterpenoid, flavonoid, and phenol. However, alkaloid level was unable to be determined. The identification of Baeckea frutescens and its possible role in selectively inhibiting glucose consumption in breast cancer cells defines a new role of natural product that can be utilised as an effective agent that regulates metabolic reprogramming in breast cancer.

Knowledge, attitude and health seeking practice on bats-borne diseases among residents of Tioman Island, Malaysia.

Bats are slowly gaining recognition as a potential reservoir for viruses harmful to human (Smith and Wang, 2013). Bats are reservoir to viruses causing Ebola virus diseases (EBV) (Leroy et al., 2005), Nipah Encephalitis (NiV) (Chua et al., 2002), SARS(Li et al., 2005) and MERS-CoV (Yang et al., 2015) being the latest one making headlines. About 18 years ago, a major outbreak of Nipah virus encephalitis occurred in Peninsular Malaysia resulted in the deaths of 105 persons and the slaughter of approximately 1.1 million pigs. In 2006, a novel bat orthoreovirus was found to be associated with acute respiratory syndrome in Malaysia. Following that incidents, many studies have been done on bats, particularly to determine their species, behaviour, and antibody level and there were also studies in human on antibody prevalence to batsrelated viruses e.g. Nipah and Hendra and PRV. Humans may become infected with viruses from bats through intermediate host (swine, horse) or through aerosol or direct contact with bats. Communities living adjacent to bat roosts should aware of possible risk of infection transmission from bats. An earlier study in Guatemala demonstrated that risk of exposure to bats in communities near bats roosts was common, but recognition of the potential for disease transmission from bats was low (Moran et al., 2015). Surprisingly, there is no local published data on public awareness towards bats-related infection despite potential risk of getting the infection. This study aimed to determine knowledge and awareness on bat-related infections, attitudes towards bats and practices related to health-seeking behaviours following exposure to bats.

Effects of Pollination by the Indo-Malaya Stingless Bee (Hymenoptera: Apidae) on the Quality of Greenhouse-Produced Rockmelon.

Rockmelon (Cucumis melo Linnaeus (Cucurbitales: Cucurbitaceae)) is a novel commercialized fruit in Malaysia and has great potential to become an important horticultural crop for the international market. In this study, we investigated the effects of pollination by the Indo-Malaya stingless bee Heterotrigona itama Smith (Hymenoptera: Apidae) on measures of yield and quality of rockmelon cultivated in the greenhouse, compared with hand cross-pollination and self-pollination. Results showed that rockmelon produced from plants pollinated by stingless bees and hand cross-pollination had higher fruit set, were heavier and larger, and contained higher numbers of seed per fruit compared with those produced by self-pollination. Pollination by stingless bees produced fruit with greater sweetness than either hand cross-pollination or self-pollination. This study demonstrated that stingless bee pollination produced rockmelon fruit of similar quality, but better yields compared to the other pollination treatments. We showed that stingless bees should be considered as an alternative, effective pollinator for the improved production of high quality rockmelon in commercial greenhouse cultivation.

Staphylococcus aureus carriage in selected kindergartens in Klang Valley.

INTRODUCTION: Nasal colonisation of S. aureus in healthy children was 18% to 30%. One to three percent of them were colonised by Methicillin-resistant Staphlycoccus aureus (MRSA). Although MRSA infection has become increasingly reported, population-based S. aureus and MRSA colonisation estimates are lacking. The main objective of this study was to determine the prevalence of S. aureus carriage among children. METHODS: Nasal samples for S. aureus culture were obtained from 250 children from three kindergartens in the Klang Valley, after consent was obtained from the children and their parents. Swabs were transported in Stuart medium, and inoculated on mannitol-salt agar within four hours of collection. Identification and disk diffusion test were done according to guidelines. Polymerase chain reaction was done on MRSA isolates for the presence of mecA and lukS/FPV genes. RESULTS: Overall prevalence of S. aureus and MRSA carriage were 19.2% (48/250) and 1.6% (4/250) respectively. mecA gene was present in all isolates, 50% isolates carried Panton-Valentine leucocidin (PVL) gene. Sccmec type I was found in 2 isolates and the remaining isolates has Sccmec type V. CONCLUSION: The prevalence of S. aureus and MRSA carriage were similar to other studies. However, risk of contracting severe infection might be higher due to presence of PVL gene in half of the MRSA isolates.

Personal And Professional Characteristics Of A Good Muslim Doctor: Perception Of Newly Graduated Doctors

The Medical Faculty of Universiti Sains Islam Malaysia (USIM) aims to produce good Muslim doctors (GMD) who are able to practise medicine that is integrated with Islamic values. Islamic courses and Medical Ethics are integrated into the curriculum in its effort to provide adequate Islamic knowledge and nurturing professionalism as a process of personal and professional development (PPD) within the framework of Islamic teaching. The objective of the study was to evaluate the perception of graduates and students of characteristics of a GMD. Method: A self-administered questionnaire was distributed to the participants. The respondents were asked to rate their level of agreement or disagreement on the statements that represent the characteristics of a GMD. Statistical analysis of the data was carried out using SPSS version 18.0. The mean, median and inter quartile ranges of the characteristics were determined and differences between the groups were analysed using Mann-Whitney U test. Results: Results showed significant difference between gender for the item “Conscious of professional ethics” (p=0.021). Significant differences were seen in the median scores between the graduates and the final year students in four out of six items for personal characteristic. Conclusion: Islamic input in the medical curriculum and the teaching of professionalism has an impact on graduate perception of characteristics of a GMD. Further improvement in the teaching of professionalism among undergraduates is necessary in order to promote greater impact on the understanding and internalization of characteristics of a GMD. The Islamic input in the medical curriculum can thus be regarded as the blueprint for PPD of medical undergraduates to become a GMD.

A case of mycotic aneurysm due to Burkholderia pseudomallei.

Burkholderia pseudomallei is an free-living gram-negative bacterium causing melioidosis and is endemic in Southeast Asia. A 56-year-old diabetic construction worker with a 1-month history of abdominal pain and 1-day history of high-grade fever was found to have a left non-dissecting infrarenal mycotic aortic aneurysm by abdominal computerized tomography scan. Bacteriological examination of his blood yielded Burkholderia pseudomallei. The patient was treated with right axillo-bifemoral bypass with excision of aneurysm and high-dose intravenous ceftazidime for two weeks, followed by oral trimethoprim/sulfamethoxazole and oral doxycycline for a minimum of five months.