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Fulltext A case of two common culprits causing pulmonary embolism

Timothy, C.T.J., Mansor, A., Wengvei, C.T.K.

JUMMEC, 2017;20(1):1-3.
MyJurnal

Pulmonary embolism is the obstruction of the pulmonary artery or its branches, commonly by thrombus or
fat. We report an unusual case of double pathology - both pulmonary thromboembolism and fat embolism
syndrome in a patient with bilateral femur and bilateral tibia fractures. This highlights the importance of a high
index of suspicion of these conditions while managing patients with multiple long bone fractures. Morbidity
and mortality can be significantly reduced with prompt and appropriate prevention strategies.
Fulltext A preliminary study of biodegradable waste as sorbent material for oil-spill cleanup

Idris J, Eyu GD, Mansor AM, Ahmad Z, Chukwuekezie CS

ScientificWorldJournal, 2014;2014:638687.
PMID: 24693241 DOI: 10.1155/2014/638687

Oil spill constitutes a major source of fresh and seawater pollution as a result of accidental discharge from tankers, marine engines, and underwater pipes. Therefore, the need for cost-effective and environmental friendly sorbent materials for oil spill cleanup cannot be overemphasized. The present work focuses on the preliminary study of empty palm fruit bunch fibre as a promising sorbent material. The morphology of the unmodified empty palm fruit bunch, EPFB fibre, was examined using an optical microcopy, scanning electron microcopy coupled with EDX and X-ray diffraction. The effects of oil volume, fibre weight, and time on oil absorption of EPFB fibre were evaluated with new engine oil from the model oil. The results show that EPFB fibre consists of numerous micro pores, hydrophobic, and partially crystalline and amorphous with approximately 13.5% carbon. The oil absorbency of the fibre increased with the increase in oil volume, immersion time, and fibre weight. However, sorption capacity decreased beyond 3 g in 100 mL. Additionally unmodified EPFB fibre showed optimum oil sorption efficiency of approximately 2.8 g/g within three days of immersion time.
A retrospective study on annual evaluation of radiation processing for frozen bone allografts complying to quality system requirements

Ramalingam S, Mohd S, Samsuddin SM, Min NG, Yusof N, Mansor A

Cell Tissue Bank, 2015 Dec;16(4):545-52.
PMID: 25687771 DOI: 10.1007/s10561-015-9501-1

Bone allografts have been used widely to fill up essential void in orthopaedic surgeries. The benefit of using allografts to replace and reconstruct musculoskeletal injuries, fractures or disease has obtained overwhelming acceptance from orthopaedic surgeons worldwide. However, bacterial infection and disease transmission through bone allograft transplantation have always been a significant issue. Sterilization by radiation is an effective method to eliminate unwanted microorganisms thus assist in preventing life threatening allograft associated infections. Femoral heads procured from living donors and long bones (femur and tibia) procured from cadaveric donors were sterilized at 25 kGy in compliance with international standard ISO 11137. According to quality requirements, all records of bone banking were evaluated annually. This retrospective study was carried out on annual evaluation of radiation records from 1998 until 2012. The minimum doses absorbed by the bones were ranging from 25.3 to 38.2 kGy while the absorbed maximum doses were from 25.4 to 42.3 kGy. All the bones supplied by our UMMC Bone Bank were sterile at the required minimum dose of 25 kGy. Our analysis on dose variation showed that the dose uniformity ratios in 37 irradiated boxes of 31 radiation batches were in the range of 1.003-1.251, which indicated the doses were well distributed.
Fulltext Acute haematogenous community-acquired methicillin-resistant Staphylococcus aureus osteomyelitis in an adult: case report and review of literature

Dhanoa A, Singh VA, Mansor A, Yusof MY, Lim KT, Thong KL

BMC Infect Dis, 2012;12:270.
PMID: 23098162 DOI: 10.1186/1471-2334-12-270

Methicillin-resistant Staphylococcus aureus (MRSA) has of late emerged as a cause of community-acquired infections among immunocompetent adults without risk factors. Skin and soft tissue infections represent the majority of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) clinical presentations, whilst invasive and life-threatening illness like necrotizing pneumonia, necrotizing fasciitis, pyomyositis, osteomyelitis and sepsis syndrome are less common. Although more widely described in the pediatric age group, the occurrence of CA-MRSA osteomyelitis in adults is an uncommonly reported entity.
Fulltext An estimate of the number of tropical tree species

Slik JW, Arroyo-Rodríguez V, Aiba S, Alvarez-Loayza P, Alves LF, Ashton P, et al.

Proc Natl Acad Sci U S A, 2015 Jun 16;112(24):7472-7.
PMID: 26034279 DOI: 10.1073/pnas.1423147112

The high species richness of tropical forests has long been recognized, yet there remains substantial uncertainty regarding the actual number of tropical tree species. Using a pantropical tree inventory database from closed canopy forests, consisting of 657,630 trees belonging to 11,371 species, we use a fitted value of Fisher's alpha and an approximate pantropical stem total to estimate the minimum number of tropical forest tree species to fall between ∼ 40,000 and ∼ 53,000, i.e., at the high end of previous estimates. Contrary to common assumption, the Indo-Pacific region was found to be as species-rich as the Neotropics, with both regions having a minimum of ∼ 19,000-25,000 tree species. Continental Africa is relatively depauperate with a minimum of ∼ 4,500-6,000 tree species. Very few species are shared among the African, American, and the Indo-Pacific regions. We provide a methodological framework for estimating species richness in trees that may help refine species richness estimates of tree-dependent taxa.
Assessing bone banking activities at University of Malaya medical centre

Mohd S, Samsuddin SM, Ramalingam S, Min NW, Yusof N, Zaman TK, et al.

Cell Tissue Bank, 2015 Dec;16(4):523-30.
PMID: 25656787 DOI: 10.1007/s10561-015-9499-4

The main advantage of establishing in-house bone banks is its ability to readily provide allograft bones for local surgeries. Bone procurement activities of our university bone bank during the 10 years of operation were reviewed. Socio-demographic data of donors, types of bone procured, cases of rejected bones and types of allograft bones transplanted are presented. From 179 potential donors, 73 % were accepted with 213 procured bones. Femoral head was the common bone transplanted (45 %), as it was also the most common procured (82 %). Bones were rejected mainly due to non-technical reasons (83 %) rather than positive results of microbiological (13 %) and serological (4 %) tests. Comprehensive data could not be obtained for further analysis due to difficulties in retrieving information. Therefore, quality assurance system was improved to establish more systematic documentations, as the basis of good banking practice with process control hence allowing traceability.
Fulltext Avoiding diagnostic pitfalls in mimics of neoplasia: the importance of a comprehensive diagnostic approach

Samsudin EZ, Kamarul T, Mansor A

Singapore Med J, 2015 May;56(5):e92-5.
PMID: 26034328 DOI: 10.11622/smedj.2015082

Any medical diagnosis should take a multimodal approach, especially those involving tumour-like conditions, as entities that mimic neoplasms have overlapping features and may present detrimental outcomes if they are underdiagnosed. These case reports present diagnostic pitfalls resulting from overdependence on a single diagnostic parameter for three musculoskeletal neoplasm mimics: brown tumour (BT) that was mistaken for giant cell tumour (GCT), methicillin-resistant Staphylococcus aureus osteomyelitis mistaken for osteosarcoma and a pseudoaneurysm mistaken for a soft tissue sarcoma. Literature reviews revealed five reports of BT simulating GCT, four reports of osteomyelitis mimicking osteosarcoma and five reports of a pseudoaneurysm imitating a soft tissue sarcoma. Our findings highlight the therapeutic dilemmas that arise with musculoskeletal mimics, as well as the importance of thorough investigation to distinguish mimickers from true neoplasms.
Fulltext Cadaveric Bone Donation amid COVID-19 Pandemic: An Unstoppable Chronicle in Uncharted Waters

Mansor A, Ramalingam S, Yusof N

Malays Orthop J, 2021 Nov;15(3):155-156.
PMID: 34966515 DOI: 10.5704/MOJ.2111.028
Fulltext Consistent patterns of common species across tropical tree communities

Cooper DLM, Lewis SL, Sullivan MJP, Prado PI, Ter Steege H, Barbier N, et al.

Nature, 2024 Jan;625(7996):728-734.
PMID: 38200314 DOI: 10.1038/s41586-023-06820-z

Trees structure the Earth's most biodiverse ecosystem, tropical forests. The vast number of tree species presents a formidable challenge to understanding these forests, including their response to environmental change, as very little is known about most tropical tree species. A focus on the common species may circumvent this challenge. Here we investigate abundance patterns of common tree species using inventory data on 1,003,805 trees with trunk diameters of at least 10 cm across 1,568 locations1-6 in closed-canopy, structurally intact old-growth tropical forests in Africa, Amazonia and Southeast Asia. We estimate that 2.2%, 2.2% and 2.3% of species comprise 50% of the tropical trees in these regions, respectively. Extrapolating across all closed-canopy tropical forests, we estimate that just 1,053 species comprise half of Earth's 800 billion tropical trees with trunk diameters of at least 10 cm. Despite differing biogeographic, climatic and anthropogenic histories7, we find notably consistent patterns of common species and species abundance distributions across the continents. This suggests that fundamental mechanisms of tree community assembly may apply to all tropical forests. Resampling analyses show that the most common species are likely to belong to a manageable list of known species, enabling targeted efforts to understand their ecology. Although they do not detract from the importance of rare species, our results open new opportunities to understand the world's most diverse forests, including modelling their response to environmental change, by focusing on the common species that constitute the majority of their trees.
Fulltext Cryptic coloration of Macaranga bancana seedlings: A unique strategy for a pioneer species

Fadzly N, Zuharah WF, Mansor A, Zakaria R

Plant Signal Behav, 2016 07 02;11(7):e1197466.
PMID: 27315145 DOI: 10.1080/15592324.2016.1197466

Macaranga bancana is considered as a successful pioneer plant species. Usually found in disturbed and open areas, most of the current research focused on its relations with ants. One of the unique feature of the plants is that the seedling leaves are red, resembling and almost matching the background. Using a portable spectrometer, we measured the color reflectance of M. bancana seedlings (less than 20 cm in height). We also measured the leaf litter reflectance, adult M. bancana leaves and also seedlings of several other species found in the vicinity of M. bancana seedlings. The reflectances of M. bancana seedlings are very similar to that of the leaf litter background. We suggest that this cryptic coloration is crucial during the early stages of the plant when it still cannot rely on the protection of ants.
Fulltext Current Status of Mimosa pigra L. Infestation in Peninsular Malaysia

Mansor A, Crawley MJ

Trop Life Sci Res, 2011 May;22(1):37-49.
PMID: 24575208 MyJurnal

The status and distribution of Mimosa pigra L., a semi-aquatic invasive species in Peninsular Malaysia, were continuously assessed between 2004 and 2007. This assessment investigated its population stand density and related weed management activities. In total, 106 sites of 6 main habitat types i.e., construction site (CS), dam/ reservoir (DM), forest reserve (FR), plantation (PL), river bank/waterway (RB) and roadside (RD) were assessed, and 55 sites were recorded with M. pigra populations. A CS is the most likely habitat to be infested with M. pigra (16 out of 18 assessed sites have this weed), whereas none of the FR visited were found to harbour M. pigra. In terms of population stand density, 41 populations were in the low range of stand density (individual plant of ≤5 m(-2)), compared to only 9 populations in the high range of stand density (individual plant of >10 m(-2)). In general, the current impact of M. pigra infestation on natural habitats is relatively low, as its distribution is only confined to disturbed areas. However, continuous monitoring of this weed species is highly recommended, especially in the riparian zone and wetland habitats.
Fulltext Deep-Freezing Temperatures During Irradiation Preserves the Compressive Strength of Human Cortical Bone Allografts: A Cadaver Study

Yang Harmony TC, Yusof N, Ramalingam S, Baharin R, Syahrom A, Mansor A

Clin Orthop Relat Res, 2022 Feb 01;480(2):407-418.
PMID: 34491235 DOI: 10.1097/CORR.0000000000001968

BACKGROUND: Gamma irradiation, which minimizes the risk of infectious disease transmission when human bone allograft is used, has been found to negatively affect its biomechanical properties. However, in those studies, the deep-freezing temperature during irradiation was not necessarily maintained during transportation and sterilization, which may have affected the findings. Prior reports have also suggested that controlled deep freezing may mitigate the detrimental effects of irradiation on the mechanical properties of bone allograft.
QUESTION/PURPOSE: Does a controlled deep-freezing temperature during irradiation help preserve the compressive mechanical properties of human femoral cortical bone allografts?
METHODS: Cortical bone cube samples, each measuring 64 mm3, were cut from the mid-diaphyseal midshaft of five fresh-frozen cadaver femurs (four male donors, mean [range] age at procurement 42 years [42 to 43]) and were allocated via block randomization into one of three experimental groups (with equal numbers of samples from each donor allocated into each group). Each experimental group consisted of 20 bone cube samples. Samples irradiated in dry ice were subjected to irradiation doses ranging from 26.7 kGy to 27.1 kGy (mean 26.9 kGy) at a deep-freezing temperature below -40°C (the recommended long-term storage temperature for allografts). Samples irradiated in gel ice underwent irradiation doses ranging from 26.2 kGy and 26.4 kGy (mean 26.3 kGy) in a freezing temperature range between -40°C and 0°C. Acting as controls, samples in a third group were not subjected to gamma irradiation. The mechanical properties (0.2% offset yield stress, ultimate compression stress, toughness, and the Young modulus) of samples from each group were subsequently evaluated via axial compression loading to failure along the long axis of the bone. The investigators were blinded to sample group during compression testing.
RESULTS: The mean ultimate compression stress (84 ± 27 MPa versus 119 ± 31 MPa, mean difference 35 [95% CI 9 to 60]; p = 0.005) and toughness (3622 ± 1720 kJ/m3 versus 5854 ± 2900 kJ/m3, mean difference 2232 [95% CI 70 to 4394]; p = 0.009) of samples irradiated at a higher temperature range (-40°C to 0°C) were lower than in those irradiated at deep-freezing temperatures (below -40°C). The mean 0.2% offset yield stress (73 ± 28 MPa versus 109 ± 38 MPa, mean difference 36 [95% CI 11 to 60]; p = 0.002) and ultimate compression stress (84 ± 27 MPa versus 128 ± 40 MPa, mean difference 44 [95% CI 17 to 69]; p < 0.001) of samples irradiated at a higher temperature range (-40°C to 0°C) were lower than the nonirradiated control group samples. The mean 0.2% offset yield stress (73 ± 28 MPa versus 101 ± 28 MPa, mean difference 28 [95% CI 3 to 52]; p = 0.02; effect size = 1.0 [95% CI 0.8 to 1.2]) of samples irradiated at higher temperature range (-40°C to 0°C) were no different with the numbers available to those irradiated at deep-freezing temperature. The mean toughness (3622 ± 1720 kJ/m3 versus 6231 ± 3410 kJ/m3, mean difference 2609 [95% CI 447 to 4771]; p = 0.02; effect size = 1.0 [95% CI 0.8 to 1.2]) of samples irradiated at higher temperature range (-40°C to 0°C) were no different with the numbers available to the non-irradiated control group samples. The mean 0.2% offset yield stress, ultimate compression stress, and toughness of samples irradiated in deep-freezing temperatures (below -40°C) were not different with the numbers available to the non-irradiated control group samples. The Young modulus was not different with the numbers available among the three groups.
CONCLUSION: In this study, maintenance of a deep-freezing temperature below -40°C, using dry ice as a cooling agent, consistently mitigated the adverse effects of irradiation on the monotonic-compression mechanical properties of human cortical bone tissue. Preserving the mechanical properties of a cortical allograft, when irradiated in a deep-freezing temperature, may have resulted from attenuation of the deleterious, indirect effects of gamma radiation on its collagen architecture in a frozen state. Immobilization of water molecules in this state prevents radiolysis and the subsequent generation of free radicals. This hypothesis was supported by an apparent loss of the protective effect when a range of higher freezing temperatures was used during irradiation.
CLINICAL RELEVANCE: Deep-freezing temperatures below -40°C during gamma irradiation may be a promising approach to better retain the native mechanical properties of cortical bone allografts. A further study of the effect of deep-freezing during gamma radiation sterilization on sterility and other important biomechanical properties of cortical bone (such as, tensile strength, fracture toughness, and fatigue) is needed to confirm these findings.
Fulltext Differential protein expression between chondrogenic differentiated MSCs, undifferentiated MSCs and adult chondrocytes derived from Oryctolagus cuniculus in vitro

Tay LX, Lim CK, Mansor A, Kamarul T

Int J Med Sci, 2014;11(1):24-33.
PMID: 24396283 DOI: 10.7150/ijms.7244

This preliminary study aims to determine the differentially expressed proteins from chondrogenic differentiated multipotent stromal cells (cMSCs) in comparison to undifferentiated multipotent stromal cells (MSCs) and adult chondrocytes (ACs).
Does bone marrow aspirate help enhance the integration of gamma irradiated allograft bone?

Thong FY, Mansor A, Ramalingam S, Yusof N

Cell Tissue Bank, 2020 Mar;21(1):107-117.
PMID: 31894432 DOI: 10.1007/s10561-019-09804-4

Bone allografts donated by other individuals offer a viable alternative to autograft. Risks of disease transmission are overcome by sterilizing the bone; unfortunately sterilization methods generally affect bone functional properties including osteogenic potential and biomechanical integrity. This study aimed to determine any enhancement effect when gamma sterilised allografts was impregnated with autologous bone marrow in improving the rate and quality of integration in metaphyseal-tibial defects of rabbits. Almost all subjects showed 50% of the defect being covered by new bones by the third week and smaller residual defect size in the treated group at the fifth week. Hounsfield units at the defect site showed increasing healing in all samples, with the treated group having an apparent advantage although insignificant (p > 0.05). In the histopathological score evaluating healing over cortical and cancellous bone at the fracture site showed only slight variations between the groups (p > 0.05). Therefore no enhanced healing by the autologous bone marrow was observed when added to the bone allografts in treating the unicortical defects.
Effect of differential forest management on land-use change (LUC) in a tropical hill forest of Malaysia

Masum KM, Mansor A, Sah SAM, Lim HS

J Environ Manage, 2017 Sep 15;200:468-474.
PMID: 28618318 DOI: 10.1016/j.jenvman.2017.06.009

Forest ownership is considered as a vital aspect for sustainable management of forest and its associated biodiversity. The Global Forest Resources Assessment 2015 reported that privately owned forest area are increasing on a global scale, but deforestation was found very active in privately owned hill forest areas of Malaysia. Penang State was purposively chosen as it has been experiencing rapid and radical changes due to urban expansion over the last three decades. In this study, analyses of land-use changes were done by PCI Geomatica using Landsat images from 1991 to 2015, future trends of land-use change were assessed using EXCEL forecast function, and its impact on the surrounding environment were conducted by reviewing already published articles on changing environment of the study area. This study revealed an annual deforestation rate of 1.4% in Penang Island since 1991. Trend analysis forecasted a forest area smaller than the current forest reserves by the year 2039. Impact analysis revealed a rapid biodiversity loss with increasing landslides, mudflows, water pollution, flash flood, and health hazard. An immediate ban over hill-land development is crucial for overall environmental safety.
Effects of processing and gamma radiation on mechanical properties and organic composition of frozen, freeze-dried and demineralised human cortical bone allograft

Mansor A, Ariffin AF, Yusof N, Mohd S, Ramalingam S, Md Saad AP, et al.

Cell Tissue Bank, 2023 Mar;24(1):25-35.
PMID: 35610332 DOI: 10.1007/s10561-022-10013-9

Bone processing and radiation were reported to influence mechanical properties of cortical bones due in part to structural changes and denaturation of collagen composition. This comparative study was to determine effects of bone processing on mechanical properties and organic composition, and to what extent the radiation damaging after each processing. Human femur cortical bones were processed by freezing, freeze-drying and demineralisation and then gamma irradiated at 5, 15, 20, 25 and 50 kGy. In the compression test, freeze drying significantly decreased the Young's Modulus by 15%, while demineralisation reduced further by 90% (P
Fulltext Establishing freeze drying process for cortical and cancellous bone allograft cubes

Ariffin, A.A., Chan, H.H., Yusof, N., Mohd, S., Ng, W.M., Mansor A.

JUMMEC, 2019;22(1):66-71.
MyJurnal

Freeze drying is a dehydration method to dry bone under freezing environment, enabling removal of water
with no or minimial effects on bone strength and durability. Larger size bones obviously require longer freeze
drying time to reduce water content to the required level for long term storage at room temperature. For small
size bone cubes or chips, it is a normal practice to pool cortical and cancellous bones for freeze drying. The
study was aimed at determining if different type of bones of the same size influence the drying time. Human
bone cubes of 10 mm x 10 mm x 10 mm were prepared from cortical bone of tibiae and cancellous bone from
femoral heads. The bone cubes were freeze dried to reduce water content to less than 6%. Moisture content
was monitored using gravimetric method.Weight and density of cortical bone were significantly higher than
cancellous bone despite of having similar small size (p
Hyaluronic acid with or without bone marrow derived-mesenchymal stem cells improves osteoarthritic knee changes in rat model: a preliminary report

Suhaeb AM, Naveen S, Mansor A, Kamarul T

Indian J Exp Biol, 2012 Jun;50(6):383-90.
PMID: 22734248

Despite being a complex degenerative joint disease, studies on osteoarthritis (OA) suggest that its progression can be reduced by the use of hyaluronic acid (HA) or mesenchymal stem cells (MSC). The present study thus aims to examine the effects of MSC, HA and the combination of HA-MSC in treating OA in rat model. The histological observations using O'Driscoll score indicate that it is the use of HA and MSC independently and not their combination that delays the progression of OA. In conclusion, the preliminary study suggest that the use of either HA or MSCs effectively reduces OA progression better than their combined use.
Fulltext Improving knowledge of doctors and paramedics through effective bone procurement workshop: A cognitive approach

Mohd S, Yusof N, Lai LL, Hossain MG, Ramalingam S, Hamid SSA, et al.

BMC Med Educ, 2019 Jul 01;19(1):238.
PMID: 31262281 DOI: 10.1186/s12909-019-1685-9

BACKGROUND: Procurement of bone allograft must be performed by trained personnel. Improper handling and lack of knowledge during bone procurement will lead to contamination hence jeopardizing quality of the procured bones and expose bone recipients to risks of infection in post-operative phase. Bone procurement workshop is the fundamental training programme to enhance skill among personnel who has been or will be involved in bone procurement. This study evaluated the effectiveness of the workshop contents including teaching materials by assessing the knowledge on bone procurement among the participants before and after the workshop.
METHODS: Bone procurement workshop was held for 2 days for doctors and paramedics. The knowledge on bone procurement was evaluated in pre- and post-assessments by answering self administration questionnaire before and after the workshop, respectively.
RESULTS: A total of 50 participants comprised of doctors and paramedics attended the workshop however only 15 (55.6%) doctors and 12 (44.4%) paramedics completed the assessments. Overall, the mean total score for the post-assessment (61.4%) was significantly higher (p
Fulltext Injury Incidence, Patterns, and Risk Factors in Functional Training Athletes in an Asian Population

Cheng TTJ, Mansor A, Lim YZ, Hossain Parash MT

Orthop J Sports Med, 2020 Oct;8(10):2325967120957412.
PMID: 33195710 DOI: 10.1177/2325967120957412

Background: Functional training, also known as CrossFit, is a unique sport that combines weightlifting, gymnastics, and metabolic conditioning into a single program. There are an estimated 50 functional training centers in Malaysia.
Purpose: To analyze the injury rates, patterns, and risk factors of functional training/CrossFit.
Study Design: Descriptive epidemiology study.
Methods: Electronic questionnaires were distributed to 244 participants from 15 centers in the country. Descriptive data regarding the athletes, injury occurrence within the past 6 months, injury details, and risk factors were collected.
Results: Of the 244 athletes, 112 (46%) developed at least 1 new injury over the previous 6 months. Injury rates were significantly higher in athletes from nonaffiliate training gyms compared with CrossFit-affiliated gyms, in athletes with previous injuries, and in those who perceived themselves as having more than average fitness.
Conclusion: Coaches and athletes need to be more aware of risk factors for injury to enable safer and better training strategies.

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