MyMedR

Displaying all 15 publications

Abstract:

Sort:

Smartic: A smart tool for Big Data analytics and IoT

Sayeed S, Ahmad AF, Peng TC

F1000Res, 2022;11:17.
PMID: 38269303 DOI: 10.12688/f1000research.73613.1

The Internet of Things (IoT) is leading the physical and digital world of technology to converge. Real-time and massive scale connections produce a large amount of versatile data, where Big Data comes into the picture. Big Data refers to large, diverse sets of information with dimensions that go beyond the capabilities of widely used database management systems, or standard data processing software tools to manage within a given limit. Almost every big dataset is dirty and may contain missing data, mistyping, inaccuracies, and many more issues that impact Big Data analytics performances. One of the biggest challenges in Big Data analytics is to discover and repair dirty data; failure to do this can lead to inaccurate analytics results and unpredictable conclusions. We experimented with different missing value imputation techniques and compared machine learning (ML) model performances with different imputation methods. We propose a hybrid model for missing value imputation combining ML and sample-based statistical techniques. Furthermore, we continued with the best missing value inputted dataset, chosen based on ML model performance for feature engineering and hyperparameter tuning. We used k-means clustering and principal component analysis. Accuracy, the evaluated outcome, improved dramatically and proved that the XGBoost model gives very high accuracy at around 0.125 root mean squared logarithmic error (RMSLE). To overcome overfitting, we used K-fold cross-validation.
The in vitro efficacy of antimicrobial agents against the pathogenic free-living amoeba Balamuthia mandrillaris

Ahmad AF, Heaselgrave W, Andrew PW, Kilvington S

J. Eukaryot. Microbiol., 2013 Sep-Oct;60(5):539-43.
PMID: 23869955 DOI: 10.1111/jeu.12062

The free-living amoeba Balamuthia mandrillaris causes usually fatal encephalitis in humans and animals. Only limited studies have investigated the efficacy of antimicrobial agents against the organism. Assay methods were developed to assess antimicrobial efficacy against both the trophozoite and cyst stage of B. mandrillaris (ATCC 50209). Amphotericin B, ciclopirox olamine, miltefosine, natamycin, paromomycin, pentamidine isethionate, protriptyline, spiramycin, sulconazole and telithromycin had limited activity with amoebacidal levels of > 135-500 μM. However, diminazene aceturate (Berenil(®) ) was amoebacidal at 7.8 μM and 31.3-61.5 μM for trophozoites and cysts, respectively. Assays for antimicrobial testing may improve the prognosis for infection and aid in the development of primary selective culture isolation media.
Serological and molecular detection of Strongyloides stercoralis infection among an Orang Asli community in Malaysia

Ahmad AF, Hadip F, Ngui R, Lim YA, Mahmud R

Parasitol Res, 2013 Aug;112(8):2811-6.
PMID: 23666229 DOI: 10.1007/s00436-013-3450-z

Detection of Strongyloides stercoralis infection particularly in asymptomatic individuals is often hampered due to the lack of standard diagnostic tools. In this study, the use of serological and molecular approaches were investigated for the detection of S. stercoralis infection among an Orang Asli (indigenous) community following a preliminary detection by microscopic examination of faecal samples. Out of 54 individuals studied, 17/54 (31.5%) were detected to be positive for S. stercoralis infection by enzyme-linked immunosorbent assay (ELISA), compared to 0/54 (0%) by faecal examination. Further confirmation performed by a nested polymerase chain reaction (PCR) using DNA extracted from faecal samples of these 17 individuals yielded 3/17 (17.6%) positives for S. stercoralis DNA amplification. No amplification was seen with the other 37 faecal samples, which were negative by microscopy and ELISA. As the high ELISA positive results were suspected to be false-positives, ELISA is not recommended for use as a detection tool but may be beneficial for evaluating the effectiveness of anti-Strongyloides drugs. The present finding indicated that PCR should be considered as an alternative diagnostic tool for the detection of S. stercoralis infection.
Fulltext Current status of parasitic infections among Pangkor Island community in Peninsular Malaysia

Ahmad AF, Ngui R, Muhammad Aidil R, Lim YA, Rohela M

Trop Biomed, 2014 Dec;31(4):836-43.
PMID: 25776610 MyJurnal

Limited data is available on the prevalence of parasitic infections among the island communities in Malaysia with most studies performed between 1960s-1980s. This study was conducted to determine the current prevalence status of parasitic infections among communities living in Pangkor Island Peninsular Malaysia. A total of 131 stool and 298 serum samples were collected and subjected to microscopic examination for intestinal protozoa and helminths and detection of Toxoplasma gondii antibodies using commercial ELISA kits respectively. In addition, thin and thick peripheral blood films were microscopically screened for the presence of Plasmodium spp. and microfilariae respectively. The overall prevalence of intestinal parasitic infections among Pangkor Island community was 9.9% (13/131) with T. trichiura (5.3%) being the most common intestinal parasite detected. Toxoplasmosis was reported in almost 60% of the community with the seroprevalence being significantly high among females (64.7%) compared to males (52.8%) (p=0.038). None of those examined samples were infected with intestinal sarcocystosis, malaria and filariasis. This study revealed that the prevalence of intestinal parasitic infections among Pangkor Island community has been greatly reduced compared to that reported 35 years ago. Massive improvements in the socioeconomic status, personal hygiene, water facilities and sanitation may have contributed to the low prevalence of parasitic infections in this community. Nevertheless, further studies still need to be performed to determine the possible risk factors for the high prevalence of toxoplasmosis in this community.
Fulltext Genetic assemblage of Sarcocystis spp. in Malaysian snakes

Lau YL, Chang PY, Subramaniam V, Ng YH, Mahmud R, Ahmad AF, et al.

Parasit Vectors, 2013 Sep 09;6(1):257.
PMID: 24010903 DOI: 10.1186/1756-3305-6-257

BACKGROUND: Sarcocystis species are protozoan parasites with a wide host range including snakes. Although there were several reports of Sarcocytis species in snakes, their distribution and prevalence are still not fully explored.
METHODS: In this study, fecal specimens of several snake species in Malaysia were examined for the presence of Sarcocystis by PCR of 18S rDNA sequence. Microscopy examination of the fecal specimens for sporocysts was not carried as it was difficult to determine the species of the infecting Sarcocystis.
RESULTS: Of the 28 snake fecal specimens, 7 were positive by PCR. BLASTn and phylogenetic analyses of the amplified 18S rDNA sequences revealed the snakes were infected with either S. nesbitti, S. singaporensis, S. zuoi or undefined Sarcocystis species.
CONCLUSION: This study is the first to report Sarcocystis infection in a cobra, and S. nesbitti in a reticulated python.
Morphological characteristics of developmental stages of Acanthamoeba and Naegleria species before and after staining by various techniques

Ithoi I, Ahmad AF, Mak JW, Nissapatorn V, Lau YL, Mahmud R

Southeast Asian J. Trop. Med. Public Health, 2011 Nov;42(6):1327-38.
PMID: 22299400

Seven stains were studied to determine the best color and contrast for staining the developmental stages of free living pathogenic Acanthamoeba and Naegleria species. The acid-fast bacilli stain (AFB) produced a blue color without contrast; trichrome-eosin and modified Field's showed various color contrasts; Giemsa, iron-hematoxylin, modified AFB and Gram produced only one color which distinguished the nucleus, nucleolus, cytoplasm, food- and water-vacuoles. The motile organs (acanthopodia, pseudopodia, lobopodia and flagella) were also clearly differentiated but produced a similar color as the cytoplasm. These motile organelles were first induced by incubating at 37 degrees C for at least 15 minutes and then fixing with methanol in order to preserve the protruding morphology prior to staining. The trichrome-eosin and iron-hematoxylin stains showed good color contrast for detecting all three stages, the trophozoite, cyst and flagellate; Giemsa and Gram stained the trophozoite and flagellate stages; the modified Field's and modified AFB stains stained only the trophozoite stage. Depending on the purpose, all these stains (except the AFB stain) can be used to identify the developmental stages of Acanthamoeba and Naegleria for clinical, epidemiological or public health use.
Fulltext Theoretical and Numerical Approaches for Determining the Reflection and Transmission Coefficients of OPEFB-PCL Composites at X-Band Frequencies

Ahmad AF, Abbas Z, Obaiys SJ, Ibrahim N, Hashim M, Khaleel H

PLoS One, 2015;10(10):e0140505.
PMID: 26474301 DOI: 10.1371/journal.pone.0140505

Bio-composites of oil palm empty fruit bunch (OPEFB) fibres and polycaprolactones (PCL) with a thickness of 1 mm were prepared and characterized. The composites produced from these materials are low in density, inexpensive, environmentally friendly, and possess good dielectric characteristics. The magnitudes of the reflection and transmission coefficients of OPEFB fibre-reinforced PCL composites with different percentages of filler were measured using a rectangular waveguide in conjunction with a microwave vector network analyzer (VNA) in the X-band frequency range. In contrast to the effective medium theory, which states that polymer-based composites with a high dielectric constant can be obtained by doping a filler with a high dielectric constant into a host material with a low dielectric constant, this paper demonstrates that the use of a low filler percentage (12.2%OPEFB) and a high matrix percentage (87.8%PCL) provides excellent results for the dielectric constant and loss factor, whereas 63.8% filler material with 36.2% host material results in lower values for both the dielectric constant and loss factor. The open-ended probe technique (OEC), connected with the Agilent vector network analyzer (VNA), is used to determine the dielectric properties of the materials under investigation. The comparative approach indicates that the mean relative error of FEM is smaller than that of NRW in terms of the corresponding S21 magnitude. The present calculation of the matrix/filler percentages endorses the exact amounts of substrate utilized in various physics applications.
Fulltext Lower ileostomy output among patients with postoperative colorectal cancer after being supplemented with partially hydrolyzed guar gum: Outcome of a pilot study

Ho CY, Majid HA, Jamhuri N, Ahmad AF, Selvarajoo TA

Nutrition, 2022 06 01;103-104:111758.
PMID: 35843037 DOI: 10.1016/j.nut.2022.111758

BACKGROUND: High stoma output is a significant complication after bowel surgery that causes dehydration, resulting in acute kidney injury, electrolyte imbalances, unintentional weight loss, and malnutrition. This study evaluates the postoperative ileostomy output among patients with colorectal cancer after being supplemented with partially hydrolyzed guar gum.
METHODS: This cross-sectional study collected sociodemographic and clinical characteristics, stoma output, and dietary intake upon discharge, hospitalization, and readmission within 30 d of discharge.
RESULTS: A total of 29 participants were recruited, with 72.4% having moderate malnutrition risk. Patients who received partially hydrolyzed guar gum (PHGG) fiber reported lower stoma output with firmer output consistency than patients who received standard care (SC) (P < 0.05 and P < 0.01). Patients who received PHGG achieved higher energy, protein, and soluble fiber intake than did the SC group (P < 0.01) upon discharge. There was a significant inverse association between soluble fiber (PHGG fiber + dietary soluble fiber) intake and ileostomy output (r, -0.494; P = 0.006).
CONCLUSIONS: Partially hydrolyzed guar gum fiber acts as an agent to hold water, reduce the speed of gastrointestinal tract transit, increase effluent viscosity, and potentially decrease water losses. Supplementation with PHGG fiber appeared to minimize ileostomy output and improve clinical outcomes among postoperative ileostomy patients. This needs to be evaluated further with a randomized controlled trial to confirm this preliminary finding.
Fulltext Detection of Naegleria species in environmental samples from Peninsular Malaysia

Ithoi I, Ahmad AF, Nissapatorn V, Lau YL, Mahmud R, Mak JW

PLoS One, 2011;6(9):e24327.
PMID: 21915311 DOI: 10.1371/journal.pone.0024327

BACKGROUND: In Malaysia, researchers and medical practitioners are unfamiliar with Naegleria infections. Thus little is known about the existence of pathogenic Naegleria fowleri, and the resultant primary amoebic meningoencephalitis (PAM) is seldom included in the differential diagnosis of central nervous system infections. This study was conducted to detect the presence of Naegleria species in various environmental samples.
METHODS/FINDINGS: A total of 41 Naegleria-like isolates were isolated from water and dust samples. All these isolates were subjected to PCR using two primer sets designed from the ITS1-ITS2 regions. The N. fowleri species-specific primer set failed to produce the expected amplicon. The Naegleria genus-specific primers produced amplicons of 408 bp (35), 450 bp (2), 457 bp (2) or 381 bp (2) from all 41 isolates isolated from aquatic (33) and dust (8) samples. Analysis of the sequences from 10 representative isolates revealed that amplicons with fragments 408, 450 and 457 bp showed homology with non-pathogenic Naegleria species, and 381 bp showed homology with Vahlkampfia species. These results concurred with the morphological observation that all 39 isolates which exhibited flagella were Naegleria, while 2 isolates (AC7, JN034055 and AC8, JN034056) that did not exhibit flagella were Vahlkampfia species.
CONCLUSION: To date, pathogenic species of N. fowleri have not been isolated from Malaysia. All 39 isolates that produced amplicons (408, 450 and 457 bp) from the genus-specific primers were identified as being similar to nonpathogenic Naegleria. Amplicon 408 bp from 5 representative isolates showed 100% and 99.7% identity to Naegleria philippinensis isolate RJTM (AM167890) and is thus believed to be the most common species in our environment. Amplicons 450 bp and 457 bp were respectively believed to be from 2 new species of Naegleria, since representative isolates showed lower homology and had a longer base pair length when compared to the reference species in the Genbank, Naegleria schusteri (AJ566626) and Naegleria laresi (AJ566630), respectively.
Fulltext Liver cirrhosis and splenomegaly associated with Schistosoma mansoni in a Sudanese woman in Malaysia: A case report

Rajoo Y, Mahmud R, Xiang NR, Omar SF, Kumar G, Lim YA, et al.

Asian Pac J Trop Med, 2015 Apr;8(4):334-6.
PMID: 25975509 DOI: 10.1016/S1995-7645(14)60341-2

We report a case of a patient with Schistosoma mansoni infection who presented with liver cirrhosis and splenomegaly. She was diagnosed by a serological test and Kato-Katz thick smear stool examination. The patient was a 52-year-old woman from Sudan who came to Malaysia for a week to visit her sons. The patient lives in the middle of Rabak region, Sudan, a highly endemic area for schistosomiasis where her daily routine includes rearing of cows and farming. The site of toilet and sources of drinking water are canals and wells; both infested with snails. Patient had a long history of exposure and coming into contact with water from these canals and wells.
Fulltext Case Report: A Symptomatic Case of Hymenolepis diminuta Infection in an Urban-Dwelling Adult in Malaysia

Ahmad AF, Ngui R, Ong J, Sarip F, Ismail WHW, Omar H, et al.

Am J Trop Med Hyg, 2017 Jul;97(1):163-165.
PMID: 28719332 DOI: 10.4269/ajtmh.15-0877

A case of Hymenolepis diminuta infection in a 43-year-old Malaysian male with persistent abdominal colicky pain is reported. Endoscopy revealed whitish worms in the lumen of the small intestine, which were identified as H. diminuta after microscopy. Patient was successfully treated with a single dose of praziquantel (25 mg/kg).
Fulltext Chemically Reduced Graphene Oxide-Reinforced Poly(Lactic Acid)/Poly(Ethylene Glycol) Nanocomposites: Preparation, Characterization, and Applications in Electromagnetic Interference Shielding

Ahmad AF, Aziz SA, Abbas Z, Obaiys SJ, Matori KA, Zaid MHM, et al.

Polymers (Basel), 2019 Apr 11;11(4).
PMID: 30978935 DOI: 10.3390/polym11040661

In this study, a nanocomposite of reduced graphene oxide (RGO) nanofiller-reinforcement poly(lactic acid) (PLA)/poly(ethylene glycol) (PEG) matrix was prepared via the melt blending method. The flexibility of PLA was improved by blending the polymer with a PEG plasticizer as a second polymer. To enhance the electromagnetic interference shielding properties of the nanocomposite, different RGO wt % were combined with the PLA/PEG blend. Using Fourier-transform infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FE-SEM) and X-ray diffraction, the structural, microstructure, and morphological properties of the polymer and the RGO/PLA/PEG nanocomposites were examined. These studies showed that the RGO addition did not considerably affect the crystallinity of the resulting nanomaterials. Thermal analysis (TGA) reveals that the addition of RGO highly improved the thermal stability of PLA/PEG nanocomposites. The dielectric properties and electromagnetic interference shielding effectiveness of the synthesized nanocomposites were calculated and showed a higher SE total value than the target value (20 dB). On the other hand, the results showed an increased power loss by increasing the frequency and conversely decreased with an increased percentage of filler.
Gastrointestinal parasites in rural dogs and cats in Selangor and Pahang states in Peninsular Malaysia

Ngui R, Lee SC, Yap NJ, Tan TK, Aidil RM, Chua KH, et al.

Acta Parasitol, 2014 Oct;59(4):737-44.
PMID: 25236287 DOI: 10.2478/s11686-014-0306-3

To estimate the current prevalence of gastrointestinal (GI) parasites in dogs and cats, a total of 105 fresh faecal samples were collected from rural areas in Peninsular Malaysia. Each faecal sample was examined for the presence of GI parasites by microscopic examination after formalin-ether concentration technique and for protozoa, trichrome and Ziehl-Neelsen staining were employed. The overall prevalence of GI parasitic infection was 88.6% (95% CI = 82.5-94.7) in which 88.3% of dogs and 89.3% of cats were infected with at least one parasites species, respectively. There were 14 different GI parasites species (nematodes, cestodes and protozoa) detected, including Ancylostoma spp. (62.9%), Toxocara spp. (32.4%), Trichuris vulpis (21.0%), Spirometra spp. (9.5%), Toxascaris leonina (5.7%), Dipylidium caninum (4.8%), Ascaris spp. (2.9%), Hymenolepis diminuta (1.0%) and others. General prevalence of GI parasites showed a significant difference between helminth (84.4%) and protozoa (34.3%) infections. Monoparasitism (38.1%) was less frequent than polyparasitism (46.7%). As several of these GI parasites are recognized as zoonotic agents, the results of this investigation revealed that local populations may be exposed to a broad spectrum of zoonotic agents by means of environmental contamination with dogs and cats faeces and this information should be used to mitigate public health risks. Prevention and control measures have to be taken in order to reduce the prevalence rates especially in socioeconomically disadvantaged communities where animals live in close proximity to people, poor levels of hygiene and overcrowding together with a lack in veterinary attention and zoonotic awareness.
Fulltext Effect of ethnicity and socioeconomic variation to the gut microbiota composition among pre-adolescent in Malaysia

Chong CW, Ahmad AF, Lim YA, Teh CS, Yap IK, Lee SC, et al.

Sci Rep, 2015;5:13338.
PMID: 26290472 DOI: 10.1038/srep13338

Gut microbiota plays an important role in mammalian host metabolism and physiological functions. The functions are particularly important in young children where rapid mental and physical developments are taking place. Nevertheless, little is known about the gut microbiome and the factors that contribute to microbial variation in the gut of South East Asian children. Here, we compared the gut bacterial richness and composition of pre-adolescence in Northern Malaysia. Our subjects covered three distinct ethnic groups with relatively narrow range of socioeconomic discrepancy. These included the Malays (n = 24), Chinese (n = 17) and the Orang Asli (indigenous) (n = 20). Our results suggested a strong ethnicity and socioeconomic-linked bacterial diversity. Highest bacterial diversity was detected from the economically deprived indigenous children while the lowest diversity was recorded from the relatively wealthy Chinese children. In addition, predicted functional metagenome profiling suggested an over-representation of pathways pertinent to bacterial colonisation and chemotaxis in the former while the latter exhibited enriched gene pathways related to sugar metabolism.
Fulltext Enterobius vermicularis salpingitis seen in the setting of ectopic pregnancy in a Malaysian patient

Ngui R, Ravindran S, Ong DB, Chow TK, Low KP, Nureena ZS, et al.

J Clin Microbiol, 2014 Sep;52(9):3468-70.
PMID: 24989613 DOI: 10.1128/JCM.01191-14

We report a rare and unusual case of invasive Enterobius vermicularis infection in a fallopian tube. The patient was a 23-year-old Malaysian woman who presented with suprapubic pain and vaginal bleeding. A clinical diagnosis of ruptured right ovarian ectopic pregnancy was made. She underwent a laparotomy with a right salpingo-oophorectomy. Histopathological examination of the right fallopian tube showed eggs and adult remnants of E. vermicularis, and the results were confirmed using PCR and DNA sequencing.

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links