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Fulltext Molecular genetic analysis of a supratentorial haemangioblastoma in a non-Von Hippel Lindau patient

Zamzuri I, Ghazali MM, Zainuddin N, Sulong S, Samarendra SM, Yusoff AAM, et al.

Med J Malaysia, 2005 Aug;60(3):360-3.
PMID: 16379193

We describe a rare tumor site in a 46 year old man who presented with a two week history of headache. Physical examination revealed bilateral papilloedema with no other localizing signs. Computed Tomographic Scan as well as Magnetic Resonance Imaging of the brain revealed a lesion with a dura tail located adjacent to the falx cerebri of the right frontal lobe. This lesion was not invading the inner table of the skull base. A tumor blush was seen on angiogram. There were no abnormalities on CT scan of the abdomen and fundoscopy was normal. Intraoperatively a vascular tumor not attached to the dura was noted and removed totally. Histopathological examination was typical of a hemangioblastoma. Analysis revealed no mutations of the VHL gene in 5 regions, exon 5-8 of the p53 gene, exon 1-2 of the p16 gene and exon 5,6 and 8 of the PTEN gene. This is the first case report of a supratentorial hemangioblastoma in a non-Von Hippel Lindau patient with genetic evidence.
Fulltext Monte Carlo dose calculation in dental amalgam phantom

Aziz MZ, Yusoff AL, Osman ND, Abdullah R, Rabaie NA, Salikin MS

J Med Phys, 2015 Jul-Sep;40(3):150-5.
PMID: 26500401 DOI: 10.4103/0971-6203.165080

It has become a great challenge in the modern radiation treatment to ensure the accuracy of treatment delivery in electron beam therapy. Tissue inhomogeneity has become one of the factors for accurate dose calculation, and this requires complex algorithm calculation like Monte Carlo (MC). On the other hand, computed tomography (CT) images used in treatment planning system need to be trustful as they are the input in radiotherapy treatment. However, with the presence of metal amalgam in treatment volume, the CT images input showed prominent streak artefact, thus, contributed sources of error. Hence, metal amalgam phantom often creates streak artifacts, which cause an error in the dose calculation. Thus, a streak artifact reduction technique was applied to correct the images, and as a result, better images were observed in terms of structure delineation and density assigning. Furthermore, the amalgam density data were corrected to provide amalgam voxel with accurate density value. As for the errors of dose uncertainties due to metal amalgam, they were reduced from 46% to as low as 2% at d80 (depth of the 80% dose beyond Zmax) using the presented strategies. Considering the number of vital and radiosensitive organs in the head and the neck regions, this correction strategy is suggested in reducing calculation uncertainties through MC calculation.
Association of p53 tumor suppressor gene with paraclinical and clinical modalities of gliomas patients in Malaysia

Yusoff AA, Abdullah J, Abdullah MR, Mohd Ariff AR, Isa MN

Acta Neurochir (Wien), 2004 Jun;146(6):595-601.
PMID: 15168228

Alteration of the tumor suppressor gene p53 is considered to be a critical step in the development of human cancer. Changes in this gene have been detected in a wide range of human tumours, including gliomas. In glioma, the presence of p53 gene alterations has been associated with worse prognosis.
Work-related musculoskeletal symptoms and coping strategies among dental auxiliaries at hospital universiti Sains Malaysia

Rahman NA, Adnan MM, Yusoff A, Shu JMH, Rustam K

Indian J Dent Res, 2020 4 5;31(1):61-66.
PMID: 32246684 DOI: 10.4103/ijdr.IJDR_430_18

Background: Dental personnel are vulnerable to work-related musculoskeletal symptoms (WMSS) due to the nature of their profession.
Aim: To determine WMSS experienced by dental auxiliaries and their coping strategies toward these symptoms.
Setting and Design: A cross-sectional study was conducted on 82 dental auxiliaries at a university dental hospital in Malaysia.
Materials and Methods: Nordic musculoskeletal questionnaire and the Brief COPE questionnaire were used to measure the musculoskeletal symptoms and coping strategies of the respondents, respectively. Data were analyzed using IBM SPSS version 22.0.
Results: Dental auxiliaries consisted of dental staff nurses (30.5%), dental surgery assistants (40.2%), dental technologists (18.3%), and healthcare assistants (11.0%). Their mean [standard deviation (SD)] age was 33.4 (7.60) years. Most of the respondents had been troubled with ache, pain, and discomfort at the neck, 54.9% (95% confidence interval 44.0%, 66.0%]. In addition, they were troubled mainly with distress at the low back (34.1%) and the ankle or feet (34.1%) which had prevented the respondents from doing their regular job over the past 12 months. The most common areas that had troubled the respondents over the past 7 days were the neck (36.6%), low back (36.6%), and ankle or feet (36.6%). The coping strategy most commonly practiced by the respondents was religion with a mean (SD) score of 3.70 (2.15), followed by active coping [3.13 (0.68)] and acceptance [3.13 (0.69)].
Conclusion: The prevalence of WMSS was high in the dental auxiliaries particularly in the neck region. The most common coping strategy used was religion. Awareness programs on the prevention of WMSS among the dental auxiliaries should be increased.
Significance of BRAFV600E mutation in intra-axial brain tumor in Malaysian patients: case series and literature review

Mohamed Yusoff AA, Abd Radzak SM, Mohd Khair SZN, Abdullah JM

Exp Oncol, 2021 06;43(2):159-167.
PMID: 34190524

BACKGROUND: To date, BRAF mutations in brain tumor patients have not been characterized in the Malaysian population. Based on the numerous reported studies, there are main mutations that exist in BRAF gene in various types of cancers. A missense mutation in codon 600 of the BRAF nuclear oncogene (BRAFV600E) is the most prevalent hotspot point mutation that has been identified in multiple human malignancies.
AIM: We here aimed to find out the frequency of BRAFV600E mutation in a series of Malaysian patients with brain tumors and if any association exists between BRAFV600E mutation and clinicopathological features of patients.
MATERIAL AND METHODS: Fresh frozen tumor tissue samples from 50 Malaysian brain tumor patients were analyzed for BRAFV600E mutational status, and its correlation with clinicopathological features (including age, gender, and tumor localization such as intra-axial: within the brain substance or extra-axial: outside the brain substance) was examined.
RESULTS: The overall BRAFV600E mutation frequency was determined to be 22% (in 11 of 50 patients). BRAFV600E was significantly correlated with the tumor location group, which shows BRAFV600E was more frequent in the intra-axial tumor than the extra-axial tumor group. In this study, we also observed that male patients were slightly more susceptible to BRAFV600E mutation, and this mutation was predominant in patients of the age group
Evaluation of engine performance and exhaust emission characteristics in a diesel engine using isobutanol- Calophyllum inophyllum biodiesel-diesel ternary blends

Alwi A, Zulkifli NW, Sukiman NL, Yusoff A, Zakaria Z, Jamshaid M, et al.

Environ Sci Pollut Res Int, 2019 Apr;26(12):11815-11826.
PMID: 30811022 DOI: 10.1007/s11356-019-04603-6

The availability of natural energy resources and the environmental issues are the most significant issues that are often highlighted by the world communities. With regard to these problems, isobutanol is a higher chain alcohol with four carbons which can be derived from biomass resources and it is potential to become an alternative fuel source besides the biodiesel for a diesel engine. The aim of this study is to evaluate the effect of isobutanol with Calophyllum inophyllum methyl ester and diesel as the ternary blend on physicochemical properties, engine performance, and emission characteristics. Five different fuel blends containing Calophyllum inophyllum biodiesel and isobutanol were tested on a single-cylinder direct injection diesel engine at different engine load of brake mean effective pressure. The physicochemical properties of the fuel blends were measured and then compared with neat diesel. The results indicate that the blend containing isobutanol and CIME gives a slight increase in BSEC and EGT and a minimal drop in BTE as compared to that of neat diesel. Besides that, the tested blends show a reduction of carbon monoxide and unburned hydrocarbon emissions. Meanwhile, all the fuel blends show a minimal increase in carbon dioxide and nitrogen oxides emissions, compared to that of neat diesel. Isobutanol can be proved as a preferred substitute for biodiesel and diesel fuels to achieve desired engine performance and emissions level.
Fulltext Awareness and Knowledge of Oral Cancer among Siamese Ethnic Group in Tumpat, Kelantan

Kassim NK, Adnan MM, Wern CW, Ru LZ, Hanafi MH, Yusoff A

Malays J Med Sci, 2017 Aug;24(4):47-54.
PMID: 28951689 MyJurnal DOI: 10.21315/mjms2017.24.4.6

INTRODUCTION: Oral cancer is a life-threatening disease. Lack of public awareness is a potent barrier for the early detection of oral cancer, especially for high-risk populations.
OBJECTIVE: This study aimed to determine the awareness and knowledge of the signs, symptoms and risk factors of oral cancer among a Siamese ethnic group in Tumpat, Kelantan.
METHODS: A cross-sectional study was conducted, using a guided questionnaire on sociodemography, habits, awareness and knowledge of the signs, symptoms and risk factors of oral cancer. Individuals under 18 years old and who had been diagnosed with oral cancer were excluded from this study.
RESULTS: A total of 195 respondents participated, 61.5% were female and the mean age was 46 (1.64). About 41% of the respondents had received secondary education and 35.4% were illiterate. Most respondents were self-employed (21.5%), followed by farmers (19.5%) and housewives (20%). The majority of them had a monthly income that fell below the poverty level of RM 830 (76.9%). Among the respondents, 22.6% had the habit of smoking, 25.6% consumed alcohol, 8.2% were betel quid chewers and 2.6% chewed tobacco. Out of 195 respondents, only 6.7% were aware of oral cancer. About 16.9% of the respondents correctly answered all of the questions regarding the signs and symptoms of oral cancer and only 4.1% knew the risk factors of oral cancer.
CONCLUSION: The awareness and knowledge of oral cancer in this targeted population were unsatisfactory. Future effective health promotion programs and education should be emphasised.
Mouse model of intracerebellar haemorrhage

Tijjani Salihu A, Muthuraju S, Aziz Mohamed Yusoff A, Ahmad F, Zulkifli Mustafa M, Jaafar H, et al.

Behav Brain Res, 2016 10 01;312:374-84.
PMID: 27327104 DOI: 10.1016/j.bbr.2016.06.034

The present study aimed to investigate the behavior and neuronal morphological changes in the perihaemorrhagic tissue of the mouse intracerebellar haemorrhage experimental model. Adult male Swiss albino mice were stereotactically infused with collagenase type VII (0.4U/μl of saline) unilaterally in to the cerebellum, following anaesthesia. Motor deficits were assessed using open field and composite score for evaluating the mouse model of cerebellar ataxia at 1, 3, 7, 14 and 21 days after collagenase infusion. The animals were sacrificed at the same time interval for evaluation of perihaematomal neuronal degeneration using haematoxylin and eosin staining and Annexin V-FITC/Propidium iodide assay. At the end of the study, it was found that infusion of 0.4U collagenase produces significant locomotor and ataxic deficit in the mice especially within the first week post surgery, and that this gradually improved within three weeks. Neuronal degeneration evident by cytoplasmic shrinkage and nuclear pyknosis was observed at the perihaematomal area after one day; especially at 3 and 7 days post haemorrhage. By 21 days, both the haematoma and degenerating neurons in the perihaematomal area were phagocytosed and the remaining neuronal cells around the scar tissue appeared normal. Moreover, Annexin-V/propidium iodide-positive cells were observed at the perihaematomal area at 3 and 7 days implying that the neurons likely die via apoptosis. It was concluded that a population of potentially salvageable neurons exist in the perihaematomal area after cerebellar haemorrhage throughout a wide time window that could be amenable to treatment.
Fulltext MabsBase: a Mycobacterium abscessus genome and annotation database

Heydari H, Wee WY, Lokanathan N, Hari R, Mohamed Yusoff A, Beh CY, et al.

PLoS One, 2013;8(4):e62443.
PMID: 23658631 DOI: 10.1371/journal.pone.0062443

Mycobacterium abscessus is a rapidly growing non-tuberculous mycobacterial species that has been associated with a wide spectrum of human infections. As the classification and biology of this organism is still not well understood, comparative genomic analysis on members of this species may provide further insights on their taxonomy, phylogeny, pathogenicity and other information that may contribute to better management of infections. The MabsBase described in this paper is a user-friendly database providing access to whole-genome sequences of newly discovered M. abscessus strains as well as resources for whole-genome annotations and computational predictions, to support the expanding scientific community interested in M. abscessus research. The MabsBase is freely available at http://mabscessus.um.edu.my.
Tackling membrane fouling in microalgae filtration using nylon 6,6 nanofiber membrane

Bilad MR, Azizo AS, Wirzal MDH, Jia Jia L, Putra ZA, Nordin NAHM, et al.

J Environ Manage, 2018 Oct 01;223:23-28.
PMID: 29885561 DOI: 10.1016/j.jenvman.2018.06.007

Microalgae technology, if managed properly, has promising roles in solving food-water-energy nexus. The Achilles' heel is, however, to lower the costs associated with cultivation and harvesting. As a favorable technique, application of membrane process is strongly limited by membrane fouling. This study evaluates performance of nylon 6,6 nanofiber membrane (NFM) to a conventional polyvinylidene fluoride phase inverted membrane (PVDF PIM) for filtration of Chlorella vulgaris. Results show that nylon 6,6 NFM is superhydrophilic, has higher size of pore opening (0.22 vs 0.18 μm) and higher surface pore density (23 vs 18 pores/μm2) leading to higher permeance (1018 vs 493 L/m2hbar) and better fouling resistant. Such advantages help to outperform the filterability of PVDF PIM by showing much higher steady-state permeance (286 vs 120 L/m2hbar), with comparable biomass retention. In addition, unlike for PVDF PIM, imposing longer relaxation cycles further enhances the performance of the NFM (i.e., 178 L/m2hbar for 0.5 min and 236 L/m2hbar for 5 min). Overall findings confirm the advantages of nylon 6,6 NFM over the PVDF PIM. Such advantages can help to reduce required membrane area and specific aeration demand by enabling higher flux and lowering aeration rate. Nevertheless, developments of nylon 6,6 NFM material with respect to its intrinsic properties, mechanical strength and operational conditions of the panel can still be explored to enhance its competitiveness as a promising fouling resistant membrane material for microalgae filtration.
Fulltext Cost analysis of facial injury treatment in two university hospitals in Malaysia: a prospective study

Saperi BS, Ramli R, Ahmed Z, Muhd Nur A, Ibrahim MI, Rashdi MF, et al.

Clinicoecon Outcomes Res, 2017;9:107-113.
PMID: 28223831 DOI: 10.2147/CEOR.S119910

OBJECTIVE: Facial injury (FI) may occur in isolation or in association with injuries to other parts of the body (facial and other injury [FOI]). The objective of this study was to determine the direct treatment costs incurred during the management of facial trauma.
MATERIALS AND METHODS: A prospective cohort study on treatment cost for FIs and FOIs due to road-traffic crashes in two university hospitals in Malaysia was conducted from July 2010 to June 2011. The patients were recruited from emergency departments and reviewed after 6 months from the date of initial treatment. Direct cost analysis, comparison of cost and length of hospital stay, and Injury Severity Score (ISS) were performed.
RESULTS: A total of 190 patients were enrolled in the study, of whom 83 (43.7%) had FI only, and 107 (56.3%) had FOI. The mean ISS was 5.4. The mean length of stay and costs for patients with FI only were 5.8 days with a total cost of US$1,261.96, whereas patients with FOI were admitted for 7.8 days with a total cost of US$1,716.47. Costs doubled if the treatment was performed under general anesthesia compared to local anesthesia.
CONCLUSION: Treatment of FI and FOI imposes a financial burden on the health care system in Malaysia.
Fulltext PGD: a pangolin genome hub for the research community

Tan TK, Tan KY, Hari R, Mohamed Yusoff A, Wong GJ, Siow CC, et al.

Database (Oxford), 2016;2016.
PMID: 27616775 DOI: 10.1093/database/baw063

Pangolins (order Pholidota) are the only mammals covered by scales. We have recently sequenced and analyzed the genomes of two critically endangered Asian pangolin species, namely the Malayan pangolin (Manis javanica) and the Chinese pangolin (Manis pentadactyla). These complete genome sequences will serve as reference sequences for future research to address issues of species conservation and to advance knowledge in mammalian biology and evolution. To further facilitate the global research effort in pangolin biology, we developed the Pangolin Genome Database (PGD), as a future hub for hosting pangolin genomic and transcriptomic data and annotations, and with useful analysis tools for the research community. Currently, the PGD provides the reference pangolin genome and transcriptome data, gene sequences and functional information, expressed transcripts, pseudogenes, genomic variations, organ-specific expression data and other useful annotations. We anticipate that the PGD will be an invaluable platform for researchers who are interested in pangolin and mammalian research. We will continue updating this hub by including more data, annotation and analysis tools particularly from our research consortium.Database URL: http://pangolin-genome.um.edu.my.
Fulltext De novo sequencing, assembly and analysis of eight different transcriptomes from the Malayan pangolin

Mohamed Yusoff A, Tan TK, Hari R, Koepfli KP, Wee WY, Antunes A, et al.

Sci Rep, 2016 09 13;6:28199.
PMID: 27618997 DOI: 10.1038/srep28199

Pangolins are scale-covered mammals, containing eight endangered species. Maintaining pangolins in captivity is a significant challenge, in part because little is known about their genetics. Here we provide the first large-scale sequencing of the critically endangered Manis javanica transcriptomes from eight different organs using Illumina HiSeq technology, yielding ~75 Giga bases and 89,754 unigenes. We found some unigenes involved in the insect hormone biosynthesis pathway and also 747 lipids metabolism-related unigenes that may be insightful to understand the lipid metabolism system in pangolins. Comparative analysis between M. javanica and other mammals revealed many pangolin-specific genes significantly over-represented in stress-related processes, cell proliferation and external stimulus, probably reflecting the traits and adaptations of the analyzed pregnant female M. javanica. Our study provides an invaluable resource for future functional works that may be highly relevant for the conservation of pangolins.

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