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Fulltext A structural study of epoxidized natural rubber (ENR-50) and its cyclic dithiocarbonate derivative using NMR spectroscopy techniques

Hamzah R, Bakar MA, Khairuddean M, Mohammed IA, Adnan R

Molecules, 2012 Sep 12;17(9):10974-93.
PMID: 22971583 DOI: 10.3390/molecules170910974

A structural study of epoxidized natural rubber (ENR-50) and its cyclic dithiocarbonate derivative was carried out using NMR spectroscopy techniques. The overlapping (1)H-NMR signals of ENR-50 at δ 1.56, 1.68-1.70, 2.06, 2.15-2.17 ppm were successfully assigned. In this work, the C=S and quaternary carbon of cyclic dithiocarbonate. All other (1)H- and (13)C-NMR chemical shifts of the derivative remain unchanged with respect to the ENR-50.
Fulltext Human hemoglobin G-Makassar variant masquerading as sickle cell anemia

Mohamad AS, Hamzah R, Selvaratnam V, Yegapan S, Sathar J

Hematol Rep, 2018 Sep 05;10(3):7210.
PMID: 30344984 DOI: 10.4081/hr.2018.7210

Human hemoglobin of G-Makassar variant has been reported very rarely with Beta Thalassemia. In year 1969 Hb GMakassar was first identified in Makassar, Sulawesi (Celebes), Republic of Indonesia. The disease was first published in 1969 and 33 years later it has been reported at a family of Thailand origin. We report a 45-yearold Malay man who was investigated for anemia and thrombocytopenia then diagnosed with Hb G-Makassar. This finding describes as a new Hemoglobin GMakassar discovered in Malaysia after 14 years diagnosed in Thailand.
Distribution of radium in oil and gas industry wastes from Malaysia

Omar M, Ali HM, Abu MP, Kontol KM, Ahmad Z, Ahmad SH, et al.

Appl Radiat Isot, 2004 May;60(5):779-82.
PMID: 15082059

Radium concentrations in 470 samples of the various types of waste from oil and gas industries were analysed using gamma spectrometers. The results showed that the radium concentration varied within a wide range. The highest mean 226Ra and 228Ra concentrations of 114,300 and 130,120 Bq/kg, respectively, were measured in scales. Overall, 75% of the waste, mostly sludge and extraction residue lies within the normal range of radium concentration in soils of Malaysia. However, some platform sludge can have radium concentration up to 560 Bq/kg.
Fulltext School bag load and its effect on erector spinae muscle and low back pain among primary school children in Malaysia

Tamrin SBM, Ai LP, Hamzah R, Abdullah MY, Hanafi SS

Malaysian Journal of Medicine and Health Sciences, 2005;1(1):21-31.

Objective: A cross-sectional study was conducted to determine and evaluate the effects of schoolbag load on electromyography (EMG) activity of the erector spinae muscle.
Methods: Eighty-four primary schoolchildren were selected from two national medium primary schools in Seri Kembangan, 42 from Primary Two (P2) and 42 from Primary Five (PS), aged 8 and 11 respectively. Data were collected through interviews, anthropometries measurements, the weight of schoolbag load and surface electromyography (SEMG) of the erector spinae using Muscle Tester ME3000f'®. SurfaceAg-AgCl electrodes were used to measure: unloaded standing and walking, and loaded standing and walking.
Results: The study revealed that the erector spinae was found to be more efficient in loaded standing probably due to other trunk muscle co-activity compared to unloaded standing (p<0.05). However, the erector spinae was less efficient when loads were carried on the back while walking, compared to unloaded walking. When the schoolbag was carried over both shoulders, forces generated by the erector spinae were reduced and resulted in a more efficient use of the erector spinae compared to other asymmetrical carrying methods (p<0.05).
Conclusions: Bending slightly forward when carrying schoolbag was found to reduce the forces generated by the erector spinae compared to normal sagittal posture (p<0.05), however no significant difference was found between the different frontal postures. A significant inverse relationship (p<0.01) between the weight of schoolbag load and the average electromyography (AEMG), showed that the signifieance of the erector spinae muscle was reduced when a heavier schoolbag load was carried, owing to other trunk muscles co-activity. The study also revealed that apart from age of schoolchildren, family history of back pain, exposure to environmental tobacco smoke (ETS), weight of the schoolbag and method of carrying schoolbag also play important role as risk factors for back pain.
Keywords: Electromyography, schoolbag, primary school, back pain
Fulltext Occult Disseminated Metastatic Breast Carcinoma Presenting as Acquired Thrombotic Thrombocytopenic Purpura

Chong SL, Ahmad Asnawi AW, Hamzah R, Liew PK, Ong TC, Tan SM, et al.

Case Rep Oncol, 2021;14(3):1814-1820.
PMID: 35111014 DOI: 10.1159/000521159

Cancer-related microangiopathic hemolytic anemia (MAHA) is a rare and life-threatening condition. We present a patient who had been treated for invasive lobular breast carcinoma in clinical remission with fever and hemolytic anemia. The peripheral blood film showed MAHA and thrombocytopenia, and a functional deficiency of ADAMTS13 activity of 23% consistent with acquired thrombotic thrombocytopenic purpura. Bone marrow aspirate and trephine biopsy confirmed metastatic carcinoma. Further evaluation revealed the involvement of multiple bone sites without recurrence of the primary tumor. The patient received a daily plasma exchange with cryosupernatant and was pulsed with corticosteroids. MAHA related to breast cancer appears to be a rare occurrence.
The pyranoxanthone inophyllin A induces oxidative stress mediated-apoptosis in Jurkat T lymphoblastic leukemia cells

Chan KM, Hamzah R, Rahaman AA, Jong VY, Khong HY, Rajab NF, et al.

Food Chem Toxicol, 2012 Aug;50(8):2916-22.
PMID: 22613213 DOI: 10.1016/j.fct.2012.04.048

Inophyllin A (INO-A), a pyranoxanthone isolated from the roots of Calophyllum inophyllum represents a new xanthone with potential chemotherapeutic activity. In this study, the molecular mechanism of INO-A-induced cell death was investigated in Jurkat T lymphoblastic leukemia cells. Assessment of phosphatidylserine exposure confirmed apoptosis as the primary mode of cell death in INO-A-treated Jurkat cells. INO-A treatment for only 30 min resulted in a significant increase of tail moment which suggests that DNA damage is an early apoptotic signal. Further flow cytometric assessment of the superoxide anion level confirmed that INO-A induced DNA damage was mediated with a concomitant generation of reactive oxygen species (ROS). Investigation on the thiols revealed an early decrease of free thiols in 30 min after 50 μM INO-A treatment. Using tetramethylrhodamine ethyl ester, a potentiometric dye, the loss of mitochondrial membrane potential (MPP) was observed in INO-A-treated cells as early as 30 min. The INO-A-induced apoptosis progressed with the simultaneous activation of caspases-2 and -9 which then led to the processing of caspase-3. Taken together, these data demonstrate that INO-A induced early oxidative stress, DNA damage and loss of MMP which subsequently led to the activation of an intrinsic pathway of apoptosis in Jurkat cells.
Clinical and haematological characteristics of 38 individuals with Hb G-Makassar in Malaysia

Esa E, Mohamad AS, Hamzah R, Hamid FSA, Aziz NA, Sevaratnam V, et al.

EJHaem, 2023 Nov;4(4):940-948.
PMID: 38024609 DOI: 10.1002/jha2.750

Haemoglobin (Hb) G-Makassar is a rare Hb variant. It presents a diagnostic challenge as it imitates sickle Hb (Hb S) in standard electrophoresis and high-performance liquid chromatography assays requiring DNA analysis to confirm diagnosis. Both have point mutations in codon 6, exon 1 in the β-globin (HBB) gene with different pathogenicities. This study describes the clinical phenotype, haematology and genotype of Hb G-Makassar. Clinical and laboratory data of 38 cases of Hb G-Makassar over 8 years were analysed. Hb G-Makassar was confirmed by a direct sequencing of HBB gene and co-inheritance of α-thalassaemia determined through multiplex gap-PCR and multiplex Amplification Refractory Mutation System polymerase chain reaction. All cases were Malays, predominantly from Terengganu (n = 20, 52.6%). There were 14 (36.8%) males and 24 (63.2%) females with median age of 25 years. Majority (n = 33, 86.8%) had features of thalassaemia trait with mean ± SD for Hb, mean cell volume (MCV) and mean cell haemoglobin (MCH) as 13.21 g/dL ± 1.69, 73.06 ± 4.48 fL and 24.71 ± 1.82 pg, respectively. None had evidence of haemolysis or thromboembolic complications. Six genotypes were identified; ßG-Makassar/ß,αα/αα (n = 19, 50.0%), ßG-Makassar/ßE,αα/αα (n = 4, 10.5%), ßG-Makassar/ßNewYork,αα/αα (n = 1, 2.6%), ßG-Makassar/ß,αα/-α (n = 11, 28.9%), ßG-Makassar/ß,αα/αAdanaα (n = 2, 5.3%) and ßG-Makassar/ß,αα/-SEA (n = 1, 2.6%). The ßG-Makassar/ß,αα/αα showed that features of thalassaemia trait with mean ± SD for Hb, MCV and MCH were 13.74 g/dL ± 2.40, 76.18 ± 6.02 fL and 25.79 ± 2.41 pg, respectively. This is the largest study reporting a significant number of Hb G-Makassar in Malaysia. Although the mutation is similar to Hb S, the phenotype is benign.
The Current State of Neurosurgery in Afghanistan

Ammar A, Nawabi NLA, Hamzah R, Berger C, Jaweed M, Park KB, et al.

World Neurosurg, 2023 Jan;169:110-117.e1.
PMID: 36270595 DOI: 10.1016/j.wneu.2022.10.048

BACKGROUND: Afghanistan has suffered through conflicts that have detrimentally impacted its health care systems. The countries' neurosurgeons have worked through wars and political upheavals to build solid practices and handle large caseloads with minimal supplies and almost no modern tools. Understanding the current state of neurosurgery in Afghanistan and the challenges faced by Afghan physicians and patients is critical to improving the country's healthcare capacity.
METHODS: To assess neurosurgery research in Afghanistan, searches were conducted in databases for articles originating from Afghanistan neurosurgeons and/or neurosurgery departments. We developed a 30-question English-language survey to assess the current state of neurosurgical capacity. Surveys were distributed to neurosurgeons throughout Afghanistan via email with the assistance of our English-speaking Afghan neurosurgical colleagues.
RESULTS: The neurosurgical disease burden of Afghanistan is poorly understood due to the lack of centralized and accessible databases. There are an estimated 124 neurosurgeons in the country based on modeled data. Surveys showed that government hospitals are poorly equipped, with private and military hospitals having access to slightly more modernized equipment but less accessible to the general population. The country lacks neurosurgery research with only 15 papers discovered through database searches deemed relevant to neurosurgery with Afghan affiliations.
CONCLUSIONS: Afghanistan is facing existential humanitarian threats. Developing the country's neurosurgical capacity and general health care capabilities is crucial. Emphasis on training physicians and establishing communication routes, and aid deliverance with the country and its leaders is key to overcoming the many crises it faces.