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A viable secondary intra-abdominal pregnancy resulting from rupture of uterine scar: role of MRI

Teng HC, Kumar G, Ramli NM

Br J Radiol, 2007 Jul;80(955):e134-6.
PMID: 17704308

Pre-natal diagnosis of intra-abdominal pregnancy is difficult. Ultrasound has been the frontline modality to date; however, it gives a diagnostic error of 50-90% and its use is disappointing. In recent years, MRI has emerged as an appealing imaging modality. With its good soft tissue contrast and non-ionizing property, it acts as a means of definitive non-invasive assessment before surgical intervention when ultrasound is inconclusive.
Unilateral moyamoya disease with co-existing arteriovenous malformation

Nawawi O, Sinnasamy M, Ramli N

Br J Radiol, 2006 Jul;79(943):e12-5.
PMID: 16823046

A case of an intracerebral bleed in a young man with a rare combination of arteriovenous malformation (AVM) and unilateral moyamoya disease is presented. The location of the bleed in the left basal ganglia corresponded to the area supplied by the basal moyamoya vessels. The AVM which received supply from collateral moyamoya vessels as well as normal cerebral arteries was located in the ipsilateral parieto-occipital region posterior to the basal ganglia bleed. This is the first reported cerebral AVM co-existing with a unilateral moyamoya disease in the English literature. Unusual features of the case such as the unilaterality of the angiographic abnormalities, their coexistence and hypotheses as to their development are discussed.
Fulltext Quantitative magnetic resonance imaging and radiogenomic biomarkers for glioma characterisation: a systematic review

Seow P, Wong JHD, Ahmad-Annuar A, Mahajan A, Abdullah NA, Ramli N

Br J Radiol, 2018 Dec;91(1092):20170930.
PMID: 29902076 DOI: 10.1259/bjr.20170930

OBJECTIVE:: The diversity of tumour characteristics among glioma patients, even within same tumour grade, is a big challenge for disease outcome prediction. A possible approach for improved radiological imaging could come from combining information obtained at the molecular level. This review assembles recent evidence highlighting the value of using radiogenomic biomarkers to infer the underlying biology of gliomas and its correlation with imaging features.
METHODS:: A literature search was done for articles published between 2002 and 2017 on Medline electronic databases. Of 249 titles identified, 38 fulfilled the inclusion criteria, with 14 articles related to quantifiable imaging parameters (heterogeneity, vascularity, diffusion, cell density, infiltrations, perfusion, and metabolite changes) and 24 articles relevant to molecular biomarkers linked to imaging.
RESULTS:: Genes found to correlate with various imaging phenotypes were EGFR, MGMT, IDH1, VEGF, PDGF, TP53, and Ki-67. EGFR is the most studied gene related to imaging characteristics in the studies reviewed (41.7%), followed by MGMT (20.8%) and IDH1 (16.7%). A summary of the relationship amongst glioma morphology, gene expressions, imaging characteristics, prognosis and therapeutic response are presented.
CONCLUSION:: The use of radiogenomics can provide insights to understanding tumour biology and the underlying molecular pathways. Certain MRI characteristics that show strong correlations with EGFR, MGMT and IDH1 could be used as imaging biomarkers. Knowing the pathways involved in tumour progression and their associated imaging patterns may assist in diagnosis, prognosis and treatment management, while facilitating personalised medicine.
ADVANCES IN KNOWLEDGE:: Radiogenomics can offer clinicians better insight into diagnosis, prognosis, and prediction of therapeutic responses of glioma.
Fulltext Herpes zoster keratouveitis with hypopyon and hyphema

Katherine SBH, Ngim YS, Juliana J, Ramli N

Taiwan J Ophthalmol, 2020 03 04;10(1):54-57.
PMID: 32309125 DOI: 10.4103/tjo.tjo_20_18

This study aims to report two cases with an uncommon, early manifestation of herpes zoster ophthalmicus which is keratouveitis. The first patient is a 61-year-old female who had presented with painful facial skin eruption and right eye redness without impairment of vision. She was treated initially as herpes zoster blepharoconjunctivitis; however, the disease had progressed to neurotrophic keratitis with severe anterior chamber reaction manifested by a mixture of hypopyon and hyphema. The second patient is a 74-year-old female who had presented after 2 weeks of facial skin eruption with blurring of vision and similar keratouveitic manifestations. Both patients had poor visual outcome due to severe ocular inflammation.
Fulltext Venipuncture versus heel prick for blood glucose monitoring in neonates

Saththasivam P, Umadevan D, Ramli N, Voralu K, Naing NN, Ilias MI, et al.

Singapore Med J, 2009 Oct;50(10):1004-7.
PMID: 19907892

The aim of this study was to determine whether there was a difference in the pain indicators and effectiveness between venipuncture (VP) and heel prick (HP) for blood glucose monitoring in term neonates (recently, venipuncture was shown superior for the Guthrie test).
Fulltext Bilateral internal carotid artery hypotrophy in malignant osteopetrosis

Ramli N, Rahmat K, Tan GP

Singapore Med J, 2008 Jul;49(7):e175-7.
PMID: 18695851

Malignant osteopetrosis is associated with petrous carotid canal and internal carotid artery stenosis in the skull base. We present a four-year-old boy with malignant osteopetrosis who developed right frontal lobe infarction as a result of bilateral internal carotid artery hypotrophy.
Fulltext A child with atypical teratoid/rhabdoid tumour of the posterior cranial fossa

Rahmat K, Kua CH, Ramli N

Singapore Med J, 2008 Dec;49(12):e365-8.
PMID: 19122937

Primary central nervous system (CNS) atypical teratoid/rhabdoid tumours (ATRT) are highly malignant neoplasms which usually present in infancy or early childhood. Although ATRT may arise anywhere within the CNS, the majority (approximately two-thirds) arise in the cerebellum or posterior fossa, and the remainder in the cerebrum. We described the imaging characteristics of CNS ATRT in the posterior cranial fossa of a 14-month-old boy.
Fulltext Extrapulmonary sarcoidosis: unusual cause of epiphora

Ramlee N, Ramli N, Liza-Sharmini AT

Singapore Med J, 2007 Jun;48(6):e168-70.
PMID: 17538739

Sarcoidosis is a multisystemic granulomatous disease of unknown aetiology mainly affecting African-Americans, Scandinavians, and the Irish. However, individuals of other races and ethnicities are still not immune. The clinical presentations vary widely with most patients having some respiratory problems. Though extrapulmonary sarcoidosis is no longer rare, sarcoidosis involving the lacrimal sac is an infrequently-reported problem. We present a case of sarcoidosis involving the lacrimal sac in a 42-year-old Malay woman who presented with epiphora. She was successfully treated with steroids and dacryocystorhinostomy. There was no evidence of systemic involvement. It is suggested that in an unusual presentation of sarcoidosis, a thorough search should be made for localisation of other sites, lungs in particular, even in the absence of respiratory complaints.
Fulltext Real-Time In-Vehicle Air Quality Monitoring System Using Machine Learning Prediction Algorithm

Goh CC, Kamarudin LM, Zakaria A, Nishizaki H, Ramli N, Mao X, et al.

Sensors (Basel), 2021 Jul 21;21(15).
PMID: 34372192 DOI: 10.3390/s21154956

This paper presents the development of a real-time cloud-based in-vehicle air quality monitoring system that enables the prediction of the current and future cabin air quality. The designed system provides predictive analytics using machine learning algorithms that can measure the drivers' drowsiness and fatigue based on the air quality presented in the cabin car. It consists of five sensors that measure the level of CO2, particulate matter, vehicle speed, temperature, and humidity. Data from these sensors were collected in real-time from the vehicle cabin and stored in the cloud database. A predictive model using multilayer perceptron, support vector regression, and linear regression was developed to analyze the data and predict the future condition of in-vehicle air quality. The performance of these models was evaluated using the Root Mean Square Error, Mean Squared Error, Mean Absolute Error, and coefficient of determination (R2). The results showed that the support vector regression achieved excellent performance with the highest linearity between the predicted and actual data with an R2 of 0.9981.
Fulltext Diagnostic Efficacy of Synthesized 2D Digital Breast Tomosynthesis in Multi-ethnic Malaysian Population

Mumin NA, Rahmat K, Fadzli F, Ramli MT, Westerhout CJ, Ramli N, et al.

Sci Rep, 2019 02 06;9(1):1459.
PMID: 30728394 DOI: 10.1038/s41598-018-37451-4

Synthesized 2D images can be reconstructed from tomosynthesis images in breast imaging. This study aims to investigate the diagnostic efficacy of synthesized 2D images (C-View) in comparison to full field digital mammography (FFDM) when used with digital breast tomosynthesis (DBT) in multi-ethnic Malaysian population. FFDM and C-View images (n = 380) were independently evaluated by three readers through Breast Imaging Reporting and Data System (BI-RADS) categorisation, breast density and lesion characterisation. Statistical analysis was done comparing sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of C-View + DBT with FFDM + DBT as standard of reference. Very good interreader agreement in BI-RADS category and density assessment between C-View + DBT and FFDM + DBT, with high sensitivity, specificity, PPV and NPV of C-View + DBT when compared with FFDM + DBT. There was comparable PPV between C-View + DBT and FFDM + DBT, with histopathology as gold standard. High level of interreader agreement in BI-RADS category and density assessment for FFDM + DBT and C-View + DBT. There was good agreement between FFDM + DBT and C-View + DBT in mass characterization, and almost perfect agreement in calcification and asymmetric density. 52.2% lower radiation dose incurred when using C-View + DBT. Hence, synthesized 2D images are comparable to FFDM with reduction in radiation dose within the limits of Malaysian multi-ethnic population.
Fulltext Cerebral infarction pattern in tuberculous meningitis

Tai MS, Viswanathan S, Rahmat K, Nor HM, Kadir KA, Goh KJ, et al.

Sci Rep, 2016 12 13;6:38802.
PMID: 27958312 DOI: 10.1038/srep38802

Tuberculous meningitis (TBM) causes significant morbidity and mortality. The primary objective was to re-examine the concept of "TB zone" and "ischaemic zone" in cerebral infarction in patients with tuberculous meningitis. The secondary objective was to evaluate cerebral infarction, vasculitis and vasospasm in tuberculous meningitis infections. Between 2009 and 2014, TBM patients were recruited. Neuroimaging was performed and findings of cerebral infarction, vasculitis and vasospasm were recorded. Infarcts were classified based on arterial supply and Hsieh's classification. Fifty-one TBM patients were recruited of whom 34 patients (67%) had cerebral infarction. Based on Hsieh's classification, 20 patients (59%) had infarcts in both "TB zone" and "ischaemic zones". 12 patients (35%) had infarcts in "ischaemic zone" and two (6%) patients had infarcts in "TB zone". In terms of vascular supply, almost all patients (35/36) had infarcts involving perforators and cortical branches. 25 patients (73%) and 14 patients (41%) had infarcts supplied by lateral lenticulostriate and medial lenticulostriate arteries respectively. 15 patients (37%) had vasculitis. Vasospasm was present in six patients (15%). 29 patients (85%) with cerebral infarction also had leptomeningeal enhancement (p = 0.002). In summary, infarcts involved mainly perforators and cortical branches, rather than "TB zone" versus "ischaemic zone".
Fulltext Diagnostic accuracy of tomosynthesis-guided vacuum assisted breast biopsy of ultrasound occult lesions

Bohan S, Ramli Hamid MT, Chan WY, Vijayananthan A, Ramli N, Kaur S, et al.

Sci Rep, 2021 01 08;11(1):129.
PMID: 33420200 DOI: 10.1038/s41598-020-80124-4

This study aims to evaluate the diagnostic accuracy of digital breast tomosynthesis-guided vacuum assisted breast biopsy (DBT-VABB) of screening detected suspicious mammographic abnormalities comprising of calcifications, asymmetric densities, architectural distortions and spiculated masses. In this institutionally approved study, a total of 170 (n = 170) DBT-VABB were performed, 153 (90%) were for calcifications, 8 (4.7%) for spiculated mass, 5 (2.9%) for asymmetric density and 4 (2.4%) for architectural distortion. All these lesions were not detected on the corresponding ultrasound. Histopathology results revealed 140 (82.4%) benign, 9 (5.3%) borderline and 21 (12.4%) malignant lesions. The total upgrade rate at surgery was 40% for atypical ductal hyperplasia and 5.9% for ductal carcinoma in-situ. 3.6% discordant benign lesions showed no upgrade. DBT-VABB showed 100% specificity, 91.3% sensitivity and 100% positive predictive value (PPV) for detecting malignant lesions. The negative predictive value (NPV) was 80%. 2 (1.2%) patients had mild complications and 1 (0.6%) had severe pain. Our study showed that DBT-VABB was a safe and reliable method, with high sensitivity, specificity, PPV and NPV in the diagnosis of non-palpable benign and malignant breast lesions. Our data also confirmed the accuracy of DBT-VABB in detecting malignant lesions and we suggest further surgical excision in borderline lesions for a more accurate diagnostic evaluation.
Fulltext Quantitative and Qualitative Analysis of 18 Deep Convolutional Neural Network (CNN) Models with Transfer Learning to Diagnose COVID-19 on Chest X-Ray (CXR) Images

Chow LS, Tang GS, Solihin MI, Gowdh NM, Ramli N, Rahmat K

SN Comput Sci, 2023;4(2):141.
PMID: 36624807 DOI: 10.1007/s42979-022-01545-8

Coronavirus disease 2019 (COVID-19) is a disease caused by a novel strain of coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), severely affecting the lungs. Our study aims to combine both quantitative and qualitative analysis of the convolutional neural network (CNN) model to diagnose COVID-19 on chest X-ray (CXR) images. We investigated 18 state-of-the-art CNN models with transfer learning, which include AlexNet, DarkNet-19, DarkNet-53, DenseNet-201, GoogLeNet, Inception-ResNet-v2, Inception-v3, MobileNet-v2, NasNet-Large, NasNet-Mobile, ResNet-18, ResNet-50, ResNet-101, ShuffleNet, SqueezeNet, VGG-16, VGG-19, and Xception. Their performances were evaluated quantitatively using six assessment metrics: specificity, sensitivity, precision, negative predictive value (NPV), accuracy, and F1-score. The top four models with accuracy higher than 90% are VGG-16, ResNet-101, VGG-19, and SqueezeNet. The accuracy of these top four models is between 90.7% and 94.3%; the F1-score is between 90.8% and 94.3%. The VGG-16 scored the highest accuracy of 94.3% and F1-score of 94.3%. The majority voting with all the 18 CNN models and top 4 models produced an accuracy of 93.0% and 94.0%, respectively. The top four and bottom three models were chosen for the qualitative analysis. A gradient-weighted class activation mapping (Grad-CAM) was used to visualize the significant region of activation for the decision-making of image classification. Two certified radiologists performed blinded subjective voting on the Grad-CAM images in comparison with their diagnosis. The qualitative analysis showed that SqueezeNet is the closest model to the diagnosis of two certified radiologists. It demonstrated a competitively good accuracy of 90.7% and F1-score of 90.8% with 111 times fewer parameters and 7.7 times faster than VGG-16. Therefore, this study recommends both VGG-16 and SqueezeNet as additional tools for the diagnosis of COVID-19.
Low nocturnal ocular perfusion pressure as a risk factor for normal tension glaucoma

Ramli N, Nurull BS, Hairi NN, Mimiwati Z

Prev Med, 2013;57 Suppl:S47-9.
PMID: 23352960 DOI: 10.1016/j.ypmed.2013.01.007

In the absence of raised intraocular pressure (IOP), haemodynamic parameters have been implicated in the development of normal tension glaucoma (NTG). The purpose of this study is to compare 24-hour IOP and haemodynamic parameters in NTG patients and non-glaucoma patients.
Fulltext The Challenges and Future Perspective of Woven Kenaf Reinforcement in Thermoset Polymer Composites in Malaysia: A Review

Lee CH, Khalina A, Nurazzi NM, Norli A, Harussani MM, Rafiqah SA, et al.

Polymers (Basel), 2021 Apr 25;13(9).
PMID: 33922885 DOI: 10.3390/polym13091390

In this review, the challenges faced by woven kenaf thermoset polymer composites in Malaysia were addressed with respect to three major aspects: woven kenaf reinforcement quality, Malaysian citizen awareness of woven kenaf thermoset composite products, and government supports. Kenaf plantations were introduced in Malaysia in the last two decades, but have generally not produced much kenaf composite product that has been widely accepted by the public. However, woven kenaf fiber enhances the thermoset composites to a similar degree or better than other natural fibers, especially with respect to impact resistance. Woven kenaf composites have been applied in automotive structural studies in Malaysia, yet they are still far from commercialization. Hence, this review discusses the kenaf fiber woven in Malaysia, thermoset and bio-based thermoset polymers, thermoset composite processing methods and, most importantly, the challenges faced in Malaysia. This review sets guidelines, provides an overview, and shares knowledge as to the potential challenges currently faced by woven kenaf reinforcements in thermoset polymer composites, allowing researchers to shift their interests and plans for conducting future studies on woven kenaf thermoset polymer composites.
Fulltext Pathogenicity of a microsporidium isolate from the diamondback moth against Noctuid moths: characterization and implications for microbiological pest management

Ghani IA, Dieng H, Abu Hassan ZA, Ramli N, Kermani N, Satho T, et al.

PLoS One, 2013;8(12):e81642.
PMID: 24349104 DOI: 10.1371/journal.pone.0081642

Due to problems with chemical control, there is increasing interest in the use of microsporidia for control of lepidopteran pests. However, there have been few studies to evaluate the susceptibility of exotic species to microsporidia from indigenous Lepidoptera.
Fulltext Pulchrin A, a New Natural Coumarin Derivative of Enicosanthellum pulchrum, Induces Apoptosis in Ovarian Cancer Cells via Intrinsic Pathway

Nordin N, Fadaeinasab M, Mohan S, Mohd Hashim N, Othman R, Karimian H, et al.

PLoS One, 2016;11(5):e0154023.
PMID: 27136097 DOI: 10.1371/journal.pone.0154023

Drug resistance presents a challenge in chemotherapy and has attracted research interest worldwide and particular attention has been given to natural compounds to overcome this difficulty. Pulchrin A, a new compound isolated from natural products has demonstrated novel potential for development as a drug. The identification of pulchrin A was conducted using several spectroscopic techniques such as nuclear magnetic resonance, liquid chromatography mass spectrometer, infrared and ultraviolet spectrometry. The cytotoxicity effects on CAOV-3 cells indicates that pulchrin A is more active than cisplatin, which has an IC50 of 22.3 μM. Significant changes in cell morphology were present, such as cell membrane blebbing and formation of apoptotic bodies. The involvement of phosphatidylserine (PS) in apoptosis was confirmed by Annexin V-FITC after a 24 h treatment. Apoptosis was activated through the intrinsic pathway by activation of procaspases 3 and 9 as well as cleaved caspases 3 and 9 and ended at the executioner pathway, with the occurrence of DNA laddering. Apoptosis was further confirmed via gene and protein expression levels, in which Bcl-2 protein was down-regulated and Bax protein was up-regulated. Furthermore, the CAOV-3 cell cycle was disrupted at the G0/G1 phase, leading to apoptosis. Molecular modeling of Bcl-2 proteins demonstrated a high- binding affinity, which inhibited the function of Bcl-2 proteins and led to cell death. Results of the current study can shed light on the development of new therapeutic agents, particularly, human ovarian cancer treatments.
Fulltext Two-Level Scheduling for Video Transmission over Downlink OFDMA Networks

Tham ML, Chow CO, Xu YH, Ramli N

PLoS One, 2016;11(2):e0148625.
PMID: 26906398 DOI: 10.1371/journal.pone.0148625

This paper presents a two-level scheduling scheme for video transmission over downlink orthogonal frequency-division multiple access (OFDMA) networks. It aims to maximize the aggregate quality of the video users subject to the playback delay and resource constraints, by exploiting the multiuser diversity and the video characteristics. The upper level schedules the transmission of video packets among multiple users based on an overall target bit-error-rate (BER), the importance level of packet and resource consumption efficiency factor. Instead, the lower level renders unequal error protection (UEP) in terms of target BER among the scheduled packets by solving a weighted sum distortion minimization problem, where each user weight reflects the total importance level of the packets that has been scheduled for that user. Frequency-selective power is then water-filled over all the assigned subcarriers in order to leverage the potential channel coding gain. Realistic simulation results demonstrate that the proposed scheme significantly outperforms the state-of-the-art scheduling scheme by up to 6.8 dB in terms of peak-signal-to-noise-ratio (PSNR). Further test evaluates the suitability of equal power allocation which is the common assumption in the literature.
Fulltext Missense Mutation of Brain Derived Neurotrophic Factor (BDNF) Alters Neurocognitive Performance in Patients with Mild Traumatic Brain Injury: A Longitudinal Study

Narayanan V, Veeramuthu V, Ahmad-Annuar A, Ramli N, Waran V, Chinna K, et al.

PLoS One, 2016;11(7):e0158838.
PMID: 27438599 DOI: 10.1371/journal.pone.0158838

The predictability of neurocognitive outcomes in patients with traumatic brain injury is not straightforward. The extent and nature of recovery in patients with mild traumatic brain injury (mTBI) are usually heterogeneous and not substantially explained by the commonly known demographic and injury-related prognostic factors despite having sustained similar injuries or injury severity. Hence, this study evaluated the effects and association of the Brain Derived Neurotrophic Factor (BDNF) missense mutations in relation to neurocognitive performance among patients with mTBI. 48 patients with mTBI were prospectively recruited and MRI scans of the brain were performed within an average 10.1 (SD 4.2) hours post trauma with assessment of their neuropsychological performance post full Glasgow Coma Scale (GCS) recovery. Neurocognitive assessments were repeated again at 6 months follow-up. The paired t-test, Cohen's d effect size and repeated measure ANOVA were performed to delineate statistically significant differences between the groups [wildtype G allele (Val homozygotes) vs. minor A allele (Met carriers)] and their neuropsychological performance across the time point (T1 = baseline/ admission vs. T2 = 6th month follow-up). Minor A allele carriers in this study generally performed more poorly on neuropsychological testing in comparison wildtype G allele group at both time points. Significant mean differences were observed among the wildtype group in the domains of memory (M = -11.44, SD = 10.0, p = .01, d = 1.22), executive function (M = -11.56, SD = 11.7, p = .02, d = 1.05) and overall performance (M = -6.89 SD = 5.3, p = .00, d = 1.39), while the minor A allele carriers showed significant mean differences in the domains of attention (M = -11.0, SD = 13.1, p = .00, d = .86) and overall cognitive performance (M = -5.25, SD = 8.1, p = .01, d = .66).The minor A allele carriers in comparison to the wildtype G allele group, showed considerably lower scores at admission and remained impaired in most domains across the timepoints, although delayed signs of recovery were noted to be significant in the domains attention and overall cognition. In conclusion, the current study has demonstrated the role of the BDNF rs6265 Val66Met polymorphism in influencing specific neurocognitive outcomes in patients with mTBI. Findings were more detrimentally profound among Met allele carriers.
Fulltext Resistance and resilience of small-scale recirculating aquaculture systems (RAS) with or without algae to pH perturbation

Mohamed Ramli N, Giatsis C, Md Yusoff F, Verreth J, Verdegem M

PLoS One, 2018;13(4):e0195862.
PMID: 29659617 DOI: 10.1371/journal.pone.0195862

The experimental set-up of this study mimicked recirculating aquaculture systems (RAS) where water quality parameters such as dissolved oxygen, pH, temperature, and turbidity were controlled and wastes produced by fish and feeding were converted to inorganic forms. A key process in the RAS was the conversion of ammonia to nitrite and nitrite to nitrate through nitrification. It was hypothesized that algae inclusion in RAS would improve the ammonia removal from the water; thereby improving RAS water quality and stability. To test this hypothesis, the stability of the microbiota community composition in a freshwater RAS with (RAS+A) or without algae (RAS-A) was challenged by introducing an acute pH drop (from pH 7 to 4 during three hours) to the system. Stigeoclonium nanum, a periphytic freshwater microalga was used in this study. No significant effect of the algae presence was found on the resistance to the acute pH drop on ammonia conversion to nitrite and nitrite conversion to nitrate. Also the resilience of the ammonia conversion to the pH drop disruption was not affected by the addition of algae. This could be due to the low biomass of algae achieved in the RAS. However, with regard to the conversion step of nitrite to nitrate, RAS+A was significantly more resilient than RAS-A. In terms of overall bacterial communities, the composition and predictive function of the bacterial communities was significantly different between RAS+A and RAS-A.

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