What causes individual tree death in tropical forests remains a major gap in our understanding of the biology of tropical trees and leads to significant uncertainty in predicting global carbon cycle dynamics. We measured individual characteristics (diameter at breast height, wood density, growth rate, crown illumination and crown form) and environmental conditions (soil fertility and habitat suitability) for 26 425 trees ≥ 10 cm diameter at breast height belonging to 416 species in a 52-ha plot in Lambir Hills National Park, Malaysia. We used structural equation models to investigate the relationships among the different factors and tree mortality. Crown form (a proxy for mechanical damage and other stresses) and prior growth were the two most important factors related to mortality. The effect of all variables on mortality (except habitat suitability) was substantially greater than expected by chance. Tree death is the result of interactions between factors, including direct and indirect effects. Crown form/damage and prior growth mediated most of the effect of tree size, wood density, fertility and habitat suitability on mortality. Large-scale assessment of crown form or status may result in improved prediction of individual tree death at the landscape scale.
Arbuscular mycorrhizal fungi (AMF) and ectomycorrhizal fungi (EMF) produce contrasting plant-soil feedbacks, but how these feedbacks are constrained by lithology is poorly understood. We investigated the hypothesis that lithological drivers of soil fertility filter plant resource economic strategies in ways that influence the relative fitness of trees with AMF or EMF symbioses in a Bornean rain forest containing species with both mycorrhizal strategies. Using forest inventory data on 1245 tree species, we found that although AMF-hosting trees had greater relative dominance on all soil types, with declining lithological soil fertility EMF-hosting trees became more dominant. Data on 13 leaf traits and wood density for a total of 150 species showed that variation was almost always associated with soil type, whereas for six leaf traits (structural properties; carbon, nitrogen, phosphorus ratios, nitrogen isotopes), variation was also associated with mycorrhizal strategy. EMF-hosting species had slower leaf economics than AMF-hosts, demonstrating the central role of mycorrhizal symbiosis in plant resource economies. At the global scale, climate has been shown to shape forest mycorrhizal composition, but here we show that in communities it depends on soil lithology, suggesting scale-dependent abiotic factors influence feedbacks underlying the relative fitness of different mycorrhizal strategies.
INTRODUCTION: Carotid intima media thickness (CIMT) being a cost effective and easily performed technique is useful in the detection of subclinical atherosclerosis and has been shown to be a prognosticator of cardiovascular events. The primary objective of this study was to obtain the distribution of CIMT measurements, highly sensitive C reactive protein (hs-CRP) and assessing health awareness and attitudes of the Malaysian population at cardiovascular disease (CVD) risk and not receiving lipid lowering agents. Secondarily the study sought to assess the significance of the relationship between these measurements against various patient characteristics.
METHODS: Measurements of CIMT are obtained by ultrasonography of 12 sites within the common carotid artery was recorded for 123 subjects from a single centre tertiary hospital of Malaysia who had two or more CVD risk factors but were not receiving lipid lowering therapy. CVD risk factors and lipid and glucose profiles were analyzed with respect to distribution of CIMT and high-sensitivity Creactive protein (hs-CRP) values.
RESULTS: The mean-max CIMT was 0.916±0.129mm (minimum 0.630mm, maximum 1.28mm) and the mean-mean CIMT was 0.743±0.110mm (minimum 0.482mm, maximum 1.050mm) and mean hs-CRP was 0.191mg/dL (minimum 0.030mg/dL, maximum 5.440mg/dL). Multivariate analyses confirmed a significant association between increasing CIMT and increasing age, total and low density lipoprotein cholesterol while log-transformed hs-CRP levels showed significant association with increasing body mass index, waist circumference, high blood glucose and triglyceride levels. Our patients had good health awareness on CVD.
CONCLUSION: Newly defined CIMT measurements and hs-CRP levels may be useful adjunctive tools to screen for atherosclerosis in the Malaysian population. It may help in refining risk stratification on top of traditional clinical assessment.
A late preterm newborn baby presented with respiratory distress and increasing cyanosis within 2 hours of birth. Bedside transthroracic echocardiography showed a critically obstructed vertical vein in a supracardiac total anomalous pulmonary venous drainage (TAPVd). Emergency stenting of the vertical vein was successfully performed at 24 hours of life.
CT angiography (CTA) is a fast examination performed with a time-optimised contrast injection to enhance the cerebral arteries. Being a new imaging modality in our hospital, evaluation of the effectiveness of 64-row multislice CTA in detecting intracranial aneurysms in ruptured subarachnoid haemorrhage (SAH) cases is necessary. We conducted a descriptive prospective study by recruiting 30 consecutively operated SAH cases from May 2005 until November 2006. CTA findings were studied by radiologist and neurosurgeon and these were compared with operative findings. The sensitivity and specificity of CTA were 94.4% and 97.2% respectively. Approximately half of the patients were scanned within four hours and operated within 24 hours. In conclusion, CTA proves to be highly sensitive and specific in the diagnosis of intracranial aneurysms in our study.
KEY WORDS: Subarachnoid haemorrhage, Intracranial aneurysm, Computed tomography (CT), CT angiography (CTA), Sarawak
Stigmatising attitudes towards mental illness may improve with clinical exposure during medical school training. Attitudes of 48 fourth year medical students in Universiti Kebangsaan Malaysia were assessed before and after their compulsory attachment in Psychiatry, using the Attitude Towards Psychiatry-30 (ATP) and the Attitude towards Mental Illness (AMI) questionnaires. ATP scores improved significantly with training (104.8 and 114.4, pre- and post-attachment respectively) as did AMI scores (63.4 and 68.1 respectively). Both improvements were statistically significant. (ATP: z = 4.55, p < 0.0005) (AMI: z = 3.75, p < 0.0005). Attitudes towards mental illness appeared to have become more favourable with clinical training in psychiatry.
In this work, nanometer HA crystals have been synthesized via wet chemical precipitation and characterized. This research studies how key synthesis parameters affect the size and phase purity of the produced HA. Characterization work was carried out using X-ray powder diffraction method and scanning electron microscopy for phase identification and particle sizing, respectively.
BACKGROUND: Co-infection by human immunodeficiency and hepatitis C viruses (HIV/HCV) is common and results in significant morbidity and mortality despite effective antiretroviral therapies (ART).
METHOD: A retrospective and prospective evaluation of the efficacy and safety of pegylated interferon alfa 2a/2b plus ribavirin (PEG-IFN/RBV) in consecutive HIV/HCV co-infected patients treated in real life clinical practice in Malaysia.
RESULTS: Forty-five HIV/HCV co-infected patients with a median age (interquartile range, IQR) of 41 years (37; 47) were assessed for treatment with PEG-IFN/RBV. All except one are of male gender and the most common risk behaviour was injecting drug use. At baseline 75.5% was on ART and the median (IQR) CD4 count was 492 cells/μl (376; 621). The HCV genotypes (GT) were 73 % GT3 and 27% GT1. Liver biopsies in forty patients showed 10% had liver cirrhosis and another 50% had significant liver fibrosis. The treatment completion rate was 79.5% with 15.9% dropped out of treatment due to adverse effects (AE) or default and 4.6% due to lack of early virological response. The AE causing premature discontinuations were neuropsychiatric and haematological. The overall sustained virological response (SVR) was 63.6% with a trend towards higher SVR in GT3 compared with GT1 (71.9% vs. 41.7%; p=0.064). In patients with bridging fibrosis plus occasional nodules or cirrhosis on liver biopsy, the SVR was significantly lower at 20% (p=0.030) compared to those with milder fibrosis.
CONCLUSION: HIV/HCV co-infected patients can be successfully and safely treated with PEG-IFN/RBV achieving high rates of SVR except in cirrhotic patients.
Study site: co-infection clinics at Sungai Buloh Hospita
BACKGROUND: Undergraduate medical students have been the most distressed group among the student population. Depression and anxiety have been found to be more prevalent in this group of students compared to others.
OBJECTIVE: This study was conducted to determine the prevalence and predictors of suicidality among undergraduate medical students in a public university.
METHODS: This was an analytical cross-sectional study, conducted in a public university in Selangor, Malaysia. Data were collected using self-administered questionnaires from January to February 2013, and analysed using the Statistical Package for Social Sciences Software (version 21).
RESULTS: Out of 625 undergraduate medical students, 537 (85.9%) participated in the study. The prevalence of the suicidality among undergraduate medical students was 7.0%. The significant predictors of suicidality based on multiple logistic regression were the respondent's lifetime suicide attempts (Adjusted Odds Ratio, AOR 10.4, 95% CI 2.7 to 40.9); depression (AOR 5.9, 95% CI 1.5 to 23.0); breaking off a steady love relationship (AOR 5.4, 95% CI 1.3 to 22.4); hopelessness (AOR 4.9, 95% CI 1.1 to 21.6); and something valued being lost or stolen (AOR 4.4, 95% CI 1.2 to 15.9).
CONCLUSION: These findings indicate that mental health care services should be strengthened at university level. The results show a need for an intervention programme to reduce suicidality among the undergraduate medical students.
This study was conducted to determine the factors involved in predicting the onset of paraplegia in tuberculosis of the spine. A cross-sectional, case control review of 85 cases of spinal tuberculosis was conducted at the National Tuberculosis Centre in Kuala Lumpur. Sixty-nine of these cases were normal neurologically, whilst 16 cases experienced neural deficit. The data was analysed using backward logistic regression and Fishers exact probability test. The factors studied included symptoms and signs of spinal tuberculosis, common investigations for tuberculosis, and physical factors of the disease. Only the erythrocyte sedimentation rate (ESR) showed a significant difference between the neural deficit and neurologically normal groups. This suggests that the ESR may be a factor in predicting evolution of paraplegia in spinal tuberculosis. In addition, it was noted that a low proportion of patients had positive sputum smear results and bacterial culture growth for mycobacterium tuberculosis suggesting these tests are of limited value for tuberculosis of the spine.
A study to determine contamination of diluted disinfectants at different points in preparation and use in 6 Malaysian hospitals was done using the in-use test. A growth of > or = 250 organisms/ml was taken as an indication of contamination. A total of 342 (7.9%) of the 4316 freshly diluted samples collected from disinfectant bottles in the pharmacy were found to be contaminated. The bacterial isolates obtained were Pseudomonas spp. (42.4%), Moraxella spp. (22.0%), Flavobacterium spp. (11.6%) and Enterobacter spp. (4.2%). Three hundred and sixty seven out of 2278 ward stock were contaminated. The isolates were Pseudomonas spp. (48.6%), Moraxella spp. (17.8%), Acinetobacter spp. (8.9%) and Flavobacterium spp. (7.0%). Of the 9265 disinfectants in-use, 1519 (16.4%) were contaminated. Among the organisms isolated were Pseudomonas spp. (44.3%), Bacillus spp. (13.0%), Enterobacter spp. (9.5%) and Acinetobacter spp. (7.3%). The results indicated a high level of contamination of diluted disinfectants prepared in the pharmacy, stored and used in the wards. This gave a high index of suspicion that recommendations for cleaning of disinfectant containers before refilling, handling of diluted stock solutions and using of disinfectants were not closely adhered to. Standard disinfection procedures outlined in the disinfection and sterilization policy by the Ministry of Health should therefore be followed.
A 1 year longitudinal study of 156 Malaysian children from urban and suburban areas in the Klang Valley revealed that the incidence rate of diarrhoea was 23.6 per 100 person-year with abnormal faeces reported on 0.26% of the total days of observation. Diarrhoea cases were detected in children from all socioeconomic classes. Rotavirus was isolated from 12% of the diarrheic children and asymptomatic rotavirus infection occurred in 3.2% of the children. All rotaviruses isolated were group A rotaviruses with long electrophoretypic pattern.
Between August 1990 to November 1991, 905 of 2583 (35.4%) isolates of Staphylococcus aureus were found to be methicillin-resistant in a general hospital in Malaysia. A detailed study of 539 of these isolates showed a high prevalence of methicillin resistant Staphylococcus aureus (MRSA) in the surgical/orthopaedic wards, paediatric wards and the special care unit. The yield of MRSA was highest from wounds/ulcers/skin swabs accounting for 64.2 per cent followed by 6.9 per cent in blood cultures. Vancomycin remains the drug of choice with no resistance detected. The resistance to ciprofloxacin was 6.7 per cent, rifampicin 4.5 per cent and fusidic acid 2.0 per cent. Most isolates were resistant to aminoglycosides. In view of the high prevalence of MRSA in this hospital, the authorities must introduce more effective measures to control its spread as a nosocomial pathogen. Otherwise it may seriously disrupt the efficient delivery of health care services in the country.
We report here a case of a kidney transplant recipient in whom the ureter was initially implanted into the peritoneum. Excessive ultrafiltration volume and reversal of serum vs dialysate creatinine ratio when the patient was recommenced on continuous ambulatory peritoneal dialysis first suggested the diagnosis which was subsequently confirmed by a plain abdominal x-ray demonstrating placement of ureteric stent in the peritoneum. This rare complication was successfully corrected with surgical re-implantation of ureter into the bladder and 5 years later, the patient remains well with good graft function.
Tacrolimus, which bonds to an immunophilin, FK506 binding protein (FKBP) has emerged as one of the most widely used immunosuppressant post solid organ transplantation. It offers excellent patient survival rates post-transplantation and a lesser number of acute rejections as compared to cyclosporine. Tacrolimus has a narrow therapeutic window with overexposure leading to acute and chronic forms of nephrotoxicity. Remarkably few data have been published on the overexposure to tacrolimus following mild diarrhoea in post-transplant patients who received treatment with tacrolimus. We observed a post-liver transplant patient with increased trough level of tacrolimus during severe diarrhoea with no complications following a timely adjustment on the dose of tacrolimus.