Hydroxyapatite, (HA; Ca1O(PO4)6(OH)2) has been successfully applied in medical and dental applications for several years due to its excellent biocompatibility. The usage of HA in Malaysia, however, is limited due to the lack of availability. Therefore the aim of this work is to produce HA materials from both pure chemicals and from Malaysian natural limestone precursors, and to compare their bulk properties. However, parts of Malaysian natural limestone deposits actually consist of a combination of Ca(OH)2 and CaCO3. In order to utilise the limestone to produce HA material, the combination of these commercially pure chemicals as HA precursors should still work. In order to test this hypothesis, two HAs were produced by wet synthesis technique utilising (a) combination of Ca(OH)2 + CaCO3 from pure commercial chemicals [WCC] and (b) a local natural limestone [WL] precursors. The HAs produced; WCC and WL, were compacted into discs and sintered at 1250 degrees C. The characterisations and evaluations conducted were XRD, SEM-EDX, FTIR and shrinkage factor. The results indicate that WL gives slightly better bulk properties compared to WCC.
The efficacy of Virkon S, a commercial disinfectant as a virucidal spray against human enterovirus 71 (HEV71), the causative agent of the fatal form of hand, foot and mouth disease was examined. At least one log10 reduction of HEV71 titer was achieved when one spray of Virkon (1% or 2%) with ten minutes of contact time was applied. The infectivity was completely lost when four sprays of 1% or 2% Virkon were applied, suggesting that at least four sprays of 1% Virkon to the surface bound HEV71 was necessary to completely inactivate the virus. These findings suggest that Virkon S at the proper concentration is suitable to be used as an effective and easy to use disinfectant against HEV71.
From July through December 1997, 11 previously healthy children in Peninsular Malaysia succumbed to an illness clinically characterised by an acute severe refractory left-ventricular failure, following a brief prodromal illness, in the midst of an outbreak of hand, foot and mouth disease (HFMD), similar to the reported experience in Sarawak and Taiwan. Retrospective reviews of the clinical features and results of laboratory, pathological and virological investigations of cases were conducted. The median age of the 11 case-patients was 31 months (range, 13 to 49 months); 6 were males. A brief prodromal illness of 3 days (range, 2 to 5 days) was characterised by fever (axillary temperature > 38 degrees C) (100%), oral ulcers (72%), extremity rashes (45%) and significant vomiting (55%). Upon hospitalisation, 7 of 11 case-patients had features suggestive of cardiogenic shock, while 4 of 11 case-patients developed shock during hospitalisation as evidenced by marked sustained tachycardia (heart rate > or = 180 beats per minute), poor peripheral pulses and peripheral perfusion, mottled extremities, pulmonary oedema (haemorrhagic pulmonary secretions in 8 of 11 cases during tracheal intubation, often precipitated by conservative crystalloid boluses, and radiographic evidence of acute pulmonary oedema in 5 of 7 cases) and markedly impaired left ventricular function on echocardiographic examination (7 of 7 cases). Three of 4 case-patients had aseptic meningitis while one case-patient also had an acute flaccid paraparesis. Despite supportive therapy, death occurred within a median of 13.4 hours following hospitalization. Post-mortem findings (all 8 specimens examined) consistently demonstrated brain-stem encephalitis with foci of neuronal necrosis and micro-abscesses. None of the 11 specimens examined revealed histological evidence of myocarditis. Enterovirus 71 (EV71) was detected in 10 of 11 case-patients, many (7) from various sterile tissue sites (5 from central nervous tissues). No other viruses were isolated or identified. Clinical features and pathological studies closely paralleled the reported experience in Sarawak and Taiwan. The uniform necropsy findings of necrotizing brain-stem encephalitis coupled with essentially normal myocardial histology, in concert with the concurrent and consistent detection of EV71 points to a primary EV71 encephalitis; as yet unclear neurogenic mechanisms may account for the cardiovascular manifestations.
The continued depletion of tropical rainforests and fragmentation of natural habitats has led to significant ecological changes which place most top carnivores under heavy pressure. Various methods have been used to determine the status of top carnivore populations in rainforest habitats, most of which are costly in terms of equipment and time. In this study we utilized, for the first time, a rigorous track classification method to estimate population size and density of clouded leopards (Neofelis nebulosa) in Tabin Wildlife Reserve in north-eastern Borneo (Sabah). Additionally, we extrapolated our local-scale results to the regional landscape level to estimate clouded leopard population size and density in all of Sabah's reserves, taking into account the reserves' conservation status (totally protected or commercial forest reserves), their size and presence or absence of clouded leopards.
In recent years, zoonotic RNA viruses such as Nipah, SARS coronavirus, avian influenza (H5N1) and Chikungunya have emerged with global impact. The latest has now been designated by World Health Organization (WHO) as pandemic (H1N1) 2009 virus. It was first reported as an outbreak in Mexico in April, and has now caused the first influenza pandemic since 1968. By July 11, 2009, there were 105,304 confirmed cases and 463 deaths in 143 countries, including 627 cases in Malaysia1 . The rapid spread of the disease has been matched by the speed of dissemination of information and protocols, co-ordinated by WHO. The experiences of SARS and H5N1 have been enormously beneficial in preparing the world for a pandemic.
Koh and others have reported (in this issue of the MJM) the high prevalence of Methicillin resistant Staphylococcus aureus (MRSA) on doctors’ neckties. As they have pointed out, this is nothing new, and like other studies with similar findings. They also point out that patient’s confidence and satisfaction are not affected by doctor’s not wearing neckties. They also referred to the British Department of Health decision to ban the use of neckties, long sleeve shirts and jewellery, and the Scottish government’s intention to ban the wearing of white coats, including neckties, to stop the spread of infections. They support the call by The Malaysian Medical Association to avoid the use of neckties.
This paper presents a statistical method for the detection of lobar pneumonia when using digitized chest X-ray films. Each region of interest was represented by a vector of wavelet texture measures which is then multiplied by the orthogonal matrix Q(2). The first two elements of the transformed vectors were shown to have a bivariate normal distribution. Misclassification probabilities were estimated using probability ellipsoids and discriminant functions. The result of this study recommends the detection of pneumonia by constructing probability ellipsoids or discriminant function using maximum energy and maximum column sum energy texture measures where misclassification probabilities were less than 0.15.
Nasal obstruction in neonates is a potentially fatal condition because neonates are obligatory nasal breathers. Bilateral choanal atresia is therefore a neonatal emergency. Several approaches for corrections of choanal atresia are available including the helium laser: YAG. A 5-year-old Chinese girl born with bilateral choanal atresia, had birth asphyxia that required intubation. She underwent multiple surgeries for correction of choanal atresia at other hospitals but failed to improve. She was referred to Universiti Kebangsaan Malaysia Medical Center (UKMMC) after presenting with intermittent respiratory distress and cyanosis following an upper respiratory tract infection. A repeat computed tomography (CT) scan done preoperatively showed complete bony stenosis over the left choana and finding was confirmed by examination under general anesthesia. She underwent endoscopic transnasal removal of left bony atretic plate. There was no intra or postoperative complications. During follow up 10 years later, the airway on both sides remains patent.
Bioprospecting of plant-based insecticides for vector control has become an area of interest within the last two decades. Due to drawbacks of chemical insecticides, phytochemicals of plant origin with mosquito control potential are being utilized as alternative sources in integrated vector control. In this regard, the present study aimed to investigate oviposition deterring and oviciding potentials of Ipomoea cairica (L.) (Family: Convolvulaceae) crude leaf extract against dengue vectors, Aedes aegypti and Aedes albopictus. Ipomoea cairica is an indigenous plant that has demonstrated marked toxicity towards larvae of Ae. aegypti and Ae. albopictus. Leaves of I. cairica were extracted using Soxhlet apparatus with acetone as solvent. Oviposition deterrent activity and ovicidal assay was carried out in oviposition site choice tests with three different concentrations (50, 100, 450 ppm). Acetone extract of I. cairica leaf strongly inhibited oviposition with 100% repellence to Ae. aegypti at lower concentration of 100 ppm, while for Ae. albopictus was at 450 ppm. The oviposition activity index (OAI) values which ranged from -0.69 to -1.00 revealed that I. cairica demonstrated deterrent effect. In ovicidal assay, similar trend was observed whereby zero hatchability was recorded for Ae. aegypti and Ae. albopictus eggs at 100 and 450 ppm, respectively. It is noteworthy that I. cairica leaf extract had significantly elicited dual properties as oviposition deterrent and oviciding agent in both Aedes species. Reduction in egg number through oviposition deterring activity, reduction in hatching percentage and survival rates, suggested an additional hallmark of this plant to be integrated in Aedes mosquito control. Ipomoea cairica deserved to be considered as one of the potential alternative sources for the new development of novel plant based insecticides in future.
The ever-growing numbers of medical digital images and the need to share them among specialists and hospitals for better and more accurate diagnosis require that patients' privacy be protected. As a result of this, there is a need for medical image watermarking (MIW). However, MIW needs to be performed with special care for two reasons. Firstly, the watermarking procedure cannot compromise the quality of the image. Secondly, confidential patient information embedded within the image should be flawlessly retrievable without risk of error after image decompressing. Despite extensive research undertaken in this area, there is still no method available to fulfill all the requirements of MIW. This paper aims to provide a useful survey on watermarking and offer a clear perspective for interested researchers by analyzing the strengths and weaknesses of different existing methods.
This paper presents an automatic region of interest (ROI) segmentation method for application of watermarking in medical images. The advantage of using this scheme is that the proposed method is robust against different attacks such as median, Wiener, Gaussian, and sharpening filters. In other words, this technique can produce the same result for the ROI before and after these attacks. The proposed algorithm consists of three main parts; suggesting an automatic ROI detection system, evaluating the robustness of the proposed system against numerous attacks, and finally recommending an enhancement part to increase the strength of the composed system against different attacks. Results obtained from the proposed method demonstrated the promising performance of the method.
Several studies show that the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene has been associated with hypertension in various populations. The present study sought to determine the association of the I/D gene polymorphism among Malay male essential hypertensive subjects in response to ACE inhibitors (enalapril and lisinopril).
The FCGR3 locus encoding the low affinity activating receptor FcγRIII, plays a vital role in immunity triggered by cellular effector and regulatory functions. Copy number of the genes FCGR3A and FCGR3B has previously been reported to affect susceptibility to several autoimmune diseases and chronic inflammatory conditions. However, such genetic association studies often yield inconsistent results; hence require assays that are robust with low error rate. We investigated the accuracy and efficiency in estimating FCGR3 CNV by comparing Sequenom MassARRAY and paralogue ratio test-restriction enzyme digest variant ratio (PRT-REDVR). In addition, since many genetic association studies of FCGR3B CNV were carried out using real-time quantitative PCR, we have also included the evaluation of that method's performance in estimating the multi-allelic CNV of FCGR3B. The qPCR assay exhibited a considerably broader distribution of signal intensity, potentially introducing error in estimation of copy number and higher false positive rates. Both Sequenom and PRT-REDVR showed lesser systematic bias, but Sequenom skewed towards copy number normal (CN = 2). The discrepancy between Sequenom and PRT-REDVR might be attributed either to batch effects noise in individual measurements. Our study suggests that PRT-REDVR is more robust and accurate in genotyping the CNV of FCGR3, but highlights the needs of multiple independent assays for extensive validation when performing a genetic association study with multi-allelic CNVs.
Dengue is a major public health problem in many tropical and sub-tropical countries. Vascular leakage and shock are identified as the major causes of deaths in patients with severe dengue. Studies have suggested the potential role of Fc gamma receptors I (FcγRI) in the pathogenesis of dengue. We hypothesized that the circulating level of Fcγ receptor I could potentially be used as an indicator in assisting early diagnosis of severe dengue.
(18)F-Fluoromethylcholine ((18)F-FCH) has been suggested as one of the reputable imaging tracers for diagnosis of prostate tumour in PET/CT examination. Nevertheless, it has never been synthesised in Malaysia. We acknowledged the major problem with (18)F-FCH is due to its relatively low radiochemical yield at the end of synthesis (EOS). Therefore, this technical note presents improved (18)F-FCH radiochemical yields after carrying out optimisation on azeotropic drying of non-carrier-added (18)F-Fluorine.
This cross-sectional study intends to investigate the associations of musculoskeletal disorders (MSDs) among foreign labourers on a socio-economic background, occupational exposure, social lifestyle, and postures adopted during harvesting tasks. A total of 446 male respondents (263 FFB cutters; 183 FFB collectors) were studied using an interview-assisted questionnaire. OWAS was used to determine the severity of awkward posture based on videos of harvesting tasks recorded for each respondent. Analysis found that increasingly educated respondents had higher risk of developing MSDs. Shorter daily work duration and longer resting duration appear to increase the risk of neck and shoulder disorders among harvesters, which may be attributable to organizational work design. Awkward posture was a particularly significant risk factor of MSDs among FFB collectors. Among the results of the study, occupational exposure, postures and certain socio-demographic backgrounds explained some, but not all, the risk factor of MSDs among harvesters. An in-depth investigation, preferably a longitudinal study investigating the dynamic of work activities and other risk factors, such as psychosocial risk factors, are recommended.
Tick-borne encephalitis virus (TBEV) and Crimean-Congo haemorrhagic fever virus (CCHFV) are important tick-borne viruses. Despite their wide geographical distribution and ease of acquisition, the prevalence of both viruses in Malaysia is still unknown. This study was conducted to determine the seroprevalence for TBEV and CCHFV among Malaysian farm workers as a high-risk group within the population.