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  1. Ramli Hamid MT, Ab Mumin N, Abdul Hamid S, Ahmad Saman MS, Rahmat K
    Clin Radiol, 2024 Jan 10.
    PMID: 38267349 DOI: 10.1016/j.crad.2023.12.016
    AIM: To compare the diagnostic performance of abbreviated breast magnetic resonance (AB-MR) imaging (MRI) and digital breast tomosynthesis (DBT) for breast cancer detection in Malaysian women with dense breasts, using histopathology as the reference standard.

    MATERIALS AND METHODS: This was a single-centre cross-sectional study of 115 women with American College of Radiology (ACR) Breast Imaging-Reporting and Data System (BIRADS) breast density C and D on DBT with breast lesions who underwent AB-MR from June 2018 to December 2021. AB-MR was performed on a 3 T MRI system with an imaging protocol consisting of three sequences: axial T1 fat-saturated unenhanced; axial first contrast-enhanced; and subtracted first contrast-enhanced with maximum intensity projection (MIP). DBT and AB-MR images were evaluated by two radiologists blinded to the histopathology and patient outcomes. Diagnostic accuracy (sensitivity, specificity, positive predictive value [PPV] and negative predictive value [NPV]) was assessed.

    RESULT: Of the 115 women, the mean age was 50.6 years. There were 48 (41.7%) Malay, 54 (47%) Chinese, and 12 (10.4%) Indian women. The majority (n=87, 75.7%) were from the diagnostic population. Sixty-one (53.1%) were premenopausal and 54 (46.9%) postmenopausal. Seventy-eight (72.4%) had an increased risk of developing breast cancer. Ninety-one (79.1%) women had density C and 24 (20.9%) had density D. There were 164 histopathology-proven lesions; 69 (42.1%) were malignant and 95 (57.9%) were benign. There were 62.8% (n=103/164) lesions detected at DBT. All the malignant lesions 100% (n=69) and 35.7% (n=34) of benign lesions were detected. Of the 61 lesions that were not detected, 46 (75.4%) were in density C, and 15 (24.6%) were in density D. The sensitivity, specificity, PPV, and NPV for DBT were 98.5%, 34.6%, 66.3%, and 94.7%, respectively. There were 65.2% (n=107/164) lesions detected on AB-MR, with 98.6% (n=68) malignant and 41.1% (39) benign lesions detected. The sensitivity, specificity, PPV, and NPV for AB-MR were 98.5%, 43.9%, 67.2%, and 96.2%, respectively. One malignant lesion (0.6%), which was a low-grade ductal carcinoma in-situ (DCIS), was missed on AB-MR.

    CONCLUSION: The present findings suggest that both DBT and AB-MR have comparable effectiveness as an imaging method for detecting breast cancer and have high NPV for low-risk lesions in women with dense breasts.

  2. Abdul Rashid SN, Mohamad Saini SB, Abdul Hamid S, Muhammad SJ, Mahmud R, Thali MJ, et al.
    Br J Radiol, 2014 Apr;87(1036):20130472.
    PMID: 24472728 DOI: 10.1259/bjr.20130472
    The purpose of this study was to retrospectively evaluate the sensitivity, specificity and accuracy of identifying methamphetamine (MA) internal payloads in "drug mules" by plain abdominal digital radiography (DR).
  3. Al-Shami SA, Md Rawi CS, Ahmad AH, Abdul Hamid S, Mohd Nor SA
    Ecotoxicol Environ Saf, 2011 Jul;74(5):1195-202.
    PMID: 21419486 DOI: 10.1016/j.ecoenv.2011.02.022
    Abundance and diversity of benthic macroinvertebrates as well as physico-chemical parameters were investigated in five rivers of the Juru River Basin in northern Peninsula Malaysia: Ceruk Tok Kun River (CTKR), Pasir River (PR), Permatang Rawa River (PRR), Kilang Ubi River (KUR), and Juru River (JR). The physico-chemical parameters and calculated water quality index (WQI) were significantly different among the investigated rivers (ANOVA, P<0.05). The WQI classified CTKR, PR, and JR into class III (slightly polluted). However, PRR and KUR fell into class IV (polluted). High diversity and abundance of macroinvertebrates, especially the intolerant taxa, Ephemeroptera, Plecoptera, and Trichoptera, were observed in the least polluted river, CTKR. Decreasing abundance of macroinvertebrates followed the deterioration of river water quality with the least number of the most tolerant taxa collected from PR. On the basis of composition and sensitivity of macroinvertebrates to pollutants in each river, the highest Biological Monitoring Working Party (BMWP) index score of 93 was reported in CTKR (good water quality). BMWP scores in PRR and JR were 38.7 and 20.1, respectively, classifying both of them into "moderate water quality" category. Poor water quality was reported in PR and KUR. The outcome of the multivariate analysis (CCA) was highly satisfactory, explaining 43.32% of the variance for the assemblages of macroinvertebrates as influenced by 19 physical and chemical variables. According to the CCA model, we assert that there were three levels of stresses on macroinvertebrate communities in the investigated rivers: Level 1, characterized of undisturbed or slightly polluted as in the case of CTKR; Level 2, characterized by a lower habitat quality (the JR) compared to the CTKR; and Level 3 showed severe environmental stresses (PRR, PR, and KUR) primarily contributed by agricultural, industrial, and municipal discharges.
  4. Qabbani AA, Razak NHA, Kawas SA, Sheikh Abdul Hamid S, Wahbi S, Samsudin AR
    J Craniofac Surg, 2017 Jun;28(4):e318-e325.
    PMID: 28230596 DOI: 10.1097/SCS.0000000000003569
    The aim of this study was to determine the efficacy of immediate implant placement with alveolar bone augmentation on socket preservation following atraumatic tooth extraction and comparing it with a tooth alveolar socket that was allowed to heal in a conventional way.Twenty medically fit patients (8 males and 12 females aged between 18 and 40 years) who needed noncomplicated tooth extraction of mandibular premolar teeth were divided randomly and equally into 2 groups. In Group I, the empty extraction socket was left untreated and allowed to heal in a conventional way. In Group II, the immediate implant was placed and the gap between the implant and the inner buccal plate surface of the socket wall was filled with lyophilized bovine bone granules and the wound was covered with pericardium membrane. The patients were followed up clinically and radiologically for regular reviews at 1 week, 3 months, and 9 months postoperative. Cone beam computerized tomography images of the alveolar ridge and socket were analyzed to determine the structural changes of the alveolar ridge. Resonance frequency analysis was measured at 9 months for Group II to assess the degree of secondary stability of the implants by using Osstell machine.A significant difference of bone resorption of 1.49 mm (confidence interval, CI 95%, 0.63-2.35) was observed within the control group at 3 months, and 1.84 mm (P ≤ 0.05) at 9 months intervals. No significant changes of bone resorption were observed in Group II. Comparison between groups showed a highly significant difference at 3 months; 2.56 mm (CI 95% 4.22-0.90) and at 9 months intervals; 3.2 mm (CI 95%, 4.70-1.62) P ≤ 0.001 between Group I and II. High resonance frequency analysis values were observed at 9 months postoperative in Group II.In conclusion, the insertion of immediate implants in fresh extraction sockets together with grafting the circumferential gap between the bony socket wall and the implant surface with bovine bone granules was able to preserve a greater amount of alveolar ridge volume when compared with an extraction socket that was left to heal in a conventional way.
  5. Al Qabbani A, Rani KGA, Syarif J, AlKawas S, Sheikh Abdul Hamid S, Samsudin AR, et al.
    PLoS One, 2023;18(4):e0283922.
    PMID: 37018321 DOI: 10.1371/journal.pone.0283922
    Current immunological issues in bone grafting regarding the transfer of xenogeneic donor bone cells into the recipient are challenging the industry to produce safer acellular natural matrices for bone regeneration. The aim of this study was to investigate the efficacy of a novel decellularization technique for producing bovine cancellous bone scaffold and compare its physicochemical, mechanical, and biological characteristics with demineralized cancellous bone scaffold in an in-vitro study. Cancellous bone blocks were harvested from a bovine femoral head (18-24 months old) subjected to physical cleansing and chemical defatting, and further processed in two ways. Group I was subjected to demineralization, while Group II underwent decellularization through physical, chemical, and enzymatic treatments. Both were then freeze-dried, and gamma radiated, finally producing a demineralized bovine cancellous bone (DMB) scaffold and decellularized bovine cancellous bone (DCC) scaffold. Both DMB and DCC scaffolds were subjected to histological evaluation, scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), fourier-transform infrared spectroscopy (FTIR), quantification of lipid, collagen, and residual nucleic acid content, and mechanical testing. The osteogenic potential was investigated through the recellularization of scaffolds with human osteoblast cell seeding and examined for cell attachment, proliferation, and mineralization by Alizarin staining and gene expression. DCC produced a complete acellular extracellular matrix (ECM) with the absence of nucleic acid content, wider pores with extensive interconnectivity and partially retaining collagen fibrils. DCC demonstrated a higher cell proliferation rate, upregulation of osteogenic differentiation markers, and substantial mineralized nodules production. Our findings suggest that the decellularization technique produced an acellular DCC scaffold with minimal damage to ECM and possesses osteogenic potential through the mechanisms of osteoconduction, osteoinduction, and osteogenesis in-vitro.
  6. Ab Mumin N, Ramli Hamid MT, Abdul Hamid S, Chiew SF, Ahmad Saman MS, Rahmat K
    PLoS One, 2023;18(8):e0290772.
    PMID: 37624821 DOI: 10.1371/journal.pone.0290772
    OBJECTIVE: To assess the association between breast cancer tumour stroma and magnetic resonance imaging (MRI) features.

    MATERIALS AND METHODS: A total of 84 patients with treatment-naïve invasive breast cancer were enrolled into this retrospective study. The tumour stroma ratio (TSR) was estimated from the amount of tumour stroma in the pathology specimen of the breast tumour. The MRI images of the patients were analysed based on Breast Imaging Reporting and Data Systems (ACR-BIRADS) for qualitative features which include T2- weighted, diffusion-weighted images (DWI) and dynamic contrast-enhanced (DCE) for kinetic features. The mean signal intensity (SI) of Short Tau Inversion Recovery (STIR), with the ratio of STIR of the lesion and pectoralis muscle (L/M ratio) and apparent diffusion coefficient (ADC) value, were measured for the quantitative features. Correlation tests were performed to assess the relationship between TSR and MRI features.

    RESULTS: There was a significant correlation between the margin of mass, enhancement pattern, and STIR signal intensity of breast cancer and TSR. There were 54.76% (n = 46) in the low stromal group and 45.24% (n = 38) in the high stromal group. A significant association were seen between the margin of the mass and TSR (p = 0.034) between the L/M ratio (p <0.001), and between STIR SI of the lesion and TSR (p<0.001). The median L/M ratio was significantly higher in the high TSR group as compared to the lower TSR group (p < 0.001).

    CONCLUSION: Breast cancer with high stroma had spiculated margins, lower STIR signal intensity, and a heterogeneous pattern of enhancement. Hence, in this preliminary study, certain MRI features showed a potential to predict TSR.

  7. Al Qabbani A, Rani KGA, AlKawas S, Sheikh Abdul Hamid S, Yap Abdullah A, Samsudin AR, et al.
    PLoS One, 2023;18(12):e0294291.
    PMID: 38127838 DOI: 10.1371/journal.pone.0294291
    The aim of this study was to compare the ability of demineralized (DMB) and decellularized (DCC) bovine bone granules to support bone regeneration in rat calvaria critical-size defects. DMB and DCC were prepared using a previously published method. The granule size used ranged between 500 and 750 μm. A total of forty-eight Sprague-Dawley rats were divided into two groups (n = 24). A pair of 5 mm diameter defects were created on the calvaria of the rats in the right and left parietal bone in both groups. Group A animals received DMB granules and Group B received DCC granules in the right parietal defect side while the left parietal untreated defect acted as sham surgery for both groups. Four animals per group were euthanized in a CO2 chamber at day 7, 14 and 21 post-surgery and the calvaria implantation site biopsy harvested was subjected to osteogenic gene expression analysis. Another four animals per group were euthanized at days 15, 30 and 60 post surgery and the calvaria implantation site biopsy harvested was subjected to histological, immunohistochemistry, RAMAN spectroscopy and Micro-CT analysis at the mentioned time points. Statistical analysis was conducted using t-tests and ANOVA. Histomorphometry showed significantly higher new bone formation in the DCC sites (p<0.05) compared to DMB. Both DMB and DCC implantation sites showed distinct staining for osteocalcin and osteopontin proteins compared to their respective sham sites. By day 21 after implantation, DCC sites demonstrated significantly elevated mRNA levels of osteonectin (p<0.001), osteopontin (p<0.001), osteocalcin (p<0.0001), ALP (p<0.01), and BMP-2 (p<0.001) compared to DMB. However, VEGF expression showed no significant differences at this time point between the two groups. Micro-CT analysis also showed enhanced defect closure and higher bone density in DCC implanted sites while RAMAN spectra demonstrated increased abundance of collagen and bone minerals, especially, PO43- ions than DMB. In conclusion, both DMB and DCC granules demonstrated favorable osteogenic potential in critical-sized defects, with DCC exhibited superior osteoconductive, osteoinductive and osteogenesis properties.
  8. Abdul Ghani NA, Mohd Abdullah AAB, Abdul Hamid S, Yuhana MY, Ramli N
    Eur J Ophthalmol, 2020 Oct 19.
    PMID: 33070639 DOI: 10.1177/1120672120965499
    BACKGROUND: Deep cerebral venous sinus thrombosis is a reversible yet potentially serious thromboembolic event. A number of reports suggest a relationship between long-haul flights and thromboembolic events, mainly deep venous thrombosis (DVT) and pulmonary embolism (PE). It is rarely reported to cause deep cerebral venous sinus thrombosis. We report a case of a bilateral papilledema after long-haul flight secondary to deep cerebral venous sinus thrombosis with subsequent complete recovery post corticosteroid and anticoagulant therapy.

    CASE: A case of a 21-year-old woman with no known medical illness who presented with gradual painless bilateral visual loss is described. She had a history of travelling on a long-haul flight 3 weeks prior to presentation. Examination showed presence of bilateral papilloedema, no vitritis, choroiditis and retinitis. Blood investigations showed raised international normalised ratio (INR). Otherwise, workup for infectious causes of optic disc swelling, connective tissue disease screening were normal. Magnetic resonance imaging (MRI) and magnetic resonance venography (MRV) of the brain showed loss of flow signal in the right transverse sinus and the left sigmoid sinus. Blood workup for preexisting hypercoagulable state was normal. She was diagnosed with deep cerebral venous sinus thrombosis and showed complete recovery with oral corticosteroid and anticoagulant therapy.

    CONCLUSION: Deep cerebral venous sinus thrombosis is a potentially serious consequence of long-haul flights. A high index of suspicion along with radiological techniques is needed for early detection and initiation of anticoagulation for this reversible condition.

  9. Abdul Hamid S, Rahmat K, Ramli MT, Fadzli F, Jamaris S, See MH, et al.
    Medicine (Baltimore), 2018 Aug;97(31):e11412.
    PMID: 30075507 DOI: 10.1097/MD.0000000000011412
    Phyllodes tumor or cystosarcoma phyllodes is a rare fibroepithelial neoplasm which arises from the periductal stroma of the breast. They are classified as benign, borderline, and malignant based on the histologic features. However, all phyllodes tumor (PT) subtypes are regarded as having malignant potential and correct diagnosis is important for surgical management and optimal care. This study is a retrospective review of 76 women diagnosed as PT with highlights on the imaging characteristics, pathology, and surgical treatment over a 7-year period in a tertiary medical center of urban population in Malaysia. There were 45 benign, 16 borderline, and 15 malignant PT. The median age for benign PT was 43, borderline 48.5, and malignant 42 years. The Malay ethnic group constitute 52.6% of cases, with 27.6% and 18.4% in Chinese and Indian ethnic groups, respectively. On mammograms, most benign (64.3%) and 33.3% of malignant PT showed high-density lesions. Calcifications were only seen in 2 benign PT. On ultrasound, 86% of benign PT was well-circumscribed whilst 50.0% of malignant PT had irregular outline. Cystic spaces were seen in 40.0% of malignant and 9.5% of benign PT. 80% of malignant PT lesions were heterogenous. Malignant PT demonstrates tumor heterogeneity, cystic spaces, and posterior acoustic enhancement on ultrasound. Half of malignant PT showed regular borders on ultrasound and appear well circumscribed on mammogram. A total of 46 patients had wide local excision or excision biopsy whilst 30 underwent mastectomy as primary treatment. The majority of the borderline and malignant PTs in our study (75.0% and 85.7% respectively) and only 5 out of the 43 (11.6%) benign PT underwent mastectomy. There were 2 tumor recurrence in the benign PT group and 1 case in the borderline and malignant group respectively.
  10. Chainchel Singh MK, Abdul Rashid SN, Abdul Hamid S, Mahmood MS, Feng SS, Mohd Nawawi H, et al.
    Forensic Sci Int, 2020 Mar;308:110171.
    PMID: 32032870 DOI: 10.1016/j.forsciint.2020.110171
    BACKGROUND: Post-mortem Computed Tomography (PMCT) allows non-invasive or minimally invasive detection of findings that may or may not be visible during conventional autopsy, however, it does not allow the investigator to draw any conclusions regarding patency of the vessel's lumen. To address this deficiency, Post-mortem Computed Tomography Angiography (PMCTA) utilizing different contrast media and techniques have been introduced with various studies looking at the correlation between PMCTA, autopsy (gross) findings and coronary artery histology in diagnosing coronary artery disease.

    OBJECTIVES: The aim of this study is to investigate the sensitivity and specificity of PMCTA in diagnosing coronary artery stenosis using water-based contrast media introduced though the vessels of the neck, compared to the gold standard of diagnosis i.e. gross and histological evaluation of the coronary artery.

    METHOD: This was a cross sectional study of 158 arterial sections involving 37 subjects recruited from the National Institute of Forensic Medicine (IPFN), Hospital Kuala Lumpur (HKL). An unenhanced PMCT was performed followed by PMCTA using water-based contrast media introduced though the vessels of the neck. Coronary artery stenosis was determined using multiplanar reconstructionD while the degree of stenosis was determined by calculating the percentage of luminal diameter divided by the diameter of the vessel internal elastic.

    RESULTS: The analysis of PMCTA and histopathology examinations revealed a sensitivity of 61.5%, specificity of 91.7%; positive predictive value (PPV) of 40.0% and negative predictive value (NPV) of 96.4%.

    CONCLUSION: PMCTA utilizing water-based contrast introduced though the vessels of the neck yielded similar results as other methods and techniques of PMCTA. We would therefore conclude that PMCTA utilizing this technique could be used to assess the degree of calcification and the presence of significant stenosis.

  11. Ramli Hamid MT, Loi KS, Chan WY, Ab Mumin N, Abdul Hamid S, Izza Rozalli F, et al.
    Curr Med Imaging, 2023 Aug 29.
    PMID: 37649292 DOI: 10.2174/1573405620666230829150218
    BACKGROUND: The use of breast MRI for screening has increased over the past decade, mostly in women with a high risk of breast cancer. Abbreviated breast MRI (AB-MR) is introduced to make MRI a more accessible screening modality. AB-MR decreases scanning and reporting time and the overall cost of MRI.

    OBJECTIVE: This study aims to evaluate the diagnostic efficacy of abbreviated MRI protocol in detecting breast cancer in screening and diagnostic populations, using histopathology as the reference standard.

    MATERIALS AND METHODS: This is a single-centre retrospective cross-sectional study of 134 patients with 198 histologically proven breast lesions who underwent full diagnostic protocol contrast-enhanced breast MRI (FDP-MR) at the University Malaya Medical Centre (UMMC) from 1st January 2018 to 31st December 2019. AB-MR was pre-determined and evaluated with regard to the potential to detect and exclude malignancy from 3 readers of varying radiological experiences. The sensitivity of both AB-MR and FDP-MR were compared using the McNemar test, where both protocols' diagnostic performances were assessed via the receiver operating characteristic (ROC) curve. Inter-observer agreement was analysed using Fleiss Kappa.

    RESULT: There were 134 patients with 198 lesions. The average age was 50.9 years old (range 27 - 80). A total of 121 (90%) MRIs were performed for diagnostic purposes. Screening accounted for 9.4% of the cases, 55.6% (n=110) lesions were benign, and 44.4% (n=88) were malignant. The commonest benign and malignant lesions were fibrocystic change (27.3%) and invasive ductal carcinoma (78.4%). The mean sensitivity, specificity, positive predictive value, and negative predictive value for AB-MR were 0.96, 0.57, 0.68 and 0.94, respectively. Both AB-MR and FDP-MR showed excellent diagnostic performance with AUC of 0.88 and 0.96, respectively. The general inter-observer agreement of all three readers for AB-MR was substantial (k=0.69), with fair agreement demonstrated between AB-MR and FDP-MR (k=0.36).

    CONCLUSION: The study shows no evidence that the diagnostic efficacy of AB-MR is inferior to FDP-MR. AB-MR, with high sensitivity, has proven its capability in cancer detection and exclusion, especially for biologically aggressive cancers.

  12. Poli A, Abdul-Hamid S, Zaurito AE, Campagnoli F, Bevilacqua V, Sheth B, et al.
    Proc Natl Acad Sci U S A, 2021 08 03;118(31).
    PMID: 34312224 DOI: 10.1073/pnas.2010053118
    Regulatory T cells (Tregs) play fundamental roles in maintaining peripheral tolerance to prevent autoimmunity and limit legitimate immune responses, a feature hijacked in tumor microenvironments in which the recruitment of Tregs often extinguishes immune surveillance through suppression of T-effector cell signaling and tumor cell killing. The pharmacological tuning of Treg activity without impacting on T conventional (Tconv) cell activity would likely be beneficial in the treatment of various human pathologies. PIP4K2A, 2B, and 2C constitute a family of lipid kinases that phosphorylate PtdIns5P to PtdIns(4,5)P 2 They are involved in stress signaling, act as synthetic lethal targets in p53-null tumors, and in mice, the loss of PIP4K2C leads to late onset hyperinflammation. Accordingly, a human single nucleotide polymorphism (SNP) near the PIP4K2C gene is linked with susceptibility to autoimmune diseases. How PIP4Ks impact on human T cell signaling is not known. Using ex vivo human primary T cells, we found that PIP4K activity is required for Treg cell signaling and immunosuppressive activity. Genetic and pharmacological inhibition of PIP4K in Tregs reduces signaling through the PI3K, mTORC1/S6, and MAPK pathways, impairs cell proliferation, and increases activation-induced cell death while sparing Tconv. PIP4K and PI3K signaling regulate the expression of the Treg master transcriptional activator FOXP3 and the epigenetic signaling protein Ubiquitin-like containing PHD and RING finger domains 1 (UHRF1). Our studies suggest that the pharmacological inhibition of PIP4K can reprogram human Treg identity while leaving Tconv cell signaling and T-helper differentiation to largely intact potentially enhancing overall immunological activity.
  13. Dieng H, Rajasaygar S, Ahmad AH, Rawi CS, Ahmad H, Satho T, et al.
    Acta Trop, 2014 Feb;130:123-30.
    PMID: 24239749 DOI: 10.1016/j.actatropica.2013.11.001
    Despite major insecticide-based vector control programs, dengue continues to be a major threat to public health in urban areas. The reasons for this failure include the emergence of insecticide resistance and the narrowing of the spectrum of efficient products. Cigarette butts (CBs), the most commonly discarded piece of waste, also represent a major health hazard to human and animal life. CBs are impregnated with thousands of chemical compounds, many of which are highly toxic and none of which has history of resistance in mosquitoes. This study was performed to examine whether exposure to CB alters various biological parameters of parents and their progeny. We examined whether the mosquito changes its ovipositional behaviors, egg hatching, reproductive capacity, longevity and fecundity in response to CB exposure at three different concentrations. Females tended to prefer microcosms containing CBs for egg deposition than those with water only. There were equivalent rates of eclosion success among larvae from eggs that matured in CB and water environments. We also observed decreased life span among adults that survived CB exposure. Extracts of CB waste have detrimental effects on the fecundity and longevity of its offspring, while being attractive to its gravid females. These results altogether indicate that CB waste indirectly affect key adult life traits of Aedes aegypti and could conceivably be developed as a novel dengue vector control strategy, referring to previously documented direct toxicity on the larval stage. But this will require further research on CB waste effects on non-target organisms including humans.
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