Browse publications by year: 2024

  1. Septicaemia due to Vibrio vulnificus: A tropical infection not to be taken lightly
    Ding CH, Wahab WA, Saaid MS, Mokhtar MN, Abdullah FA, Azaharuddin I
    Trop Biomed, 2024 Jun 01;41(2):157-159.
    PMID: 39154267 DOI: 10.47665/tb.41.2.004
    Vibrio vulnificus is a halophilic gram-negative bacillus that can cause fulminant septicaemia in immunocompromised patients. A 67-year-old man who was immunosuppressed as a result of cytotoxic chemotherapy presented with a brief history of fever, lethargy, myalgia, and reduced oral intake. He had recently travelled to the beach to consume seafood. His blood pressure was 81/47 mm Hg, necessitating fluid resuscitation followed by inotropic support and admission to the intensive care unit. His blood culture was positive for curved gram-negative bacilli. The isolate was oxidase-positive and produced an acid butt with an alkaline slant in triple sugar iron agar. Matrix-assisted laser desorption ionization-time of flight mass spectrometry conclusively identified the isolate as V. vulnificus. Intravenous ceftazidime plus ciprofloxacin were administered, and by the fifth day of admission, he was successfully transferred out to the general ward. In total, the patient completed a 14-day course of antibiotic therapy.
    MeSH terms: Aged; Ceftazidime/therapeutic use; Ciprofloxacin/therapeutic use; Humans; Male; Vibrio Infections*; Immunocompromised Host; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  2. Preliminary studies on the effect of excretory secretory (ES) Ascaris lumbricoides antigens on colorectal cell line viability
    Ab Talib NN, Nisha M, Ramasamy R, Pang JC
    Trop Biomed, 2024 Jun 01;41(2):160-165.
    PMID: 39154268 DOI: 10.47665/tb.41.2.005
    Helminth parasites are a group of complex metazoans from various taxonomic families. Excretory secretory (ES) by-products, secreted by living parasites from the surface, appeared to modulate the host immunological response towards helminth infection. This study aims to investigate the effect of ES antigen from helminth parasite on colorectal cell viability. Worm were cultured in phosphate-buffered saline (PBS x1) at 37°C for 24 hours after being rinsed in sterile PBS. Using a mortar and pestle, the worm was crushed vigorously using PBS. The obtained excretory secretory (ES) antigens were extracted and filtered using a 0.22 µM filter and stored at -20°C for further assay. For LCMS, 100 µl of the extract was analysed using Agilent ZORBAX Eclipse Plus C18 Rapid Resolution HT. The extraction of ES antigen (10 µg/ml and 20 µg/ml) was used for cell viability studies using CRC cell line HCT 116. Cell viability and MTT assay were conducted as per the protocol mentioned in the MTT kit. The liquid chromatography and mass spectrometry (LCMS) data indicated that the ES antigen contained metabolic compounds, namely fatty acid, amino alcohol, indoles, sterols, glycosides, and sphingoids. For the Ascaris lumbricoides LCMS analyses, around 405 metabolic peaks were detected. Out of which, 58 were detected via the database were identified, while several compounds detected have anticancer properties. The MTT assay indicated that after 24 hours and 48 hours of exposure, all treated cells showed a decrease in cell viability compared to the control group. The preliminary studies demonstrated that the ES antigen from Ascaris lumbricoides has some ability to decrease the cell viability of the HCT116 CRC cell line. Further studies are needed to examine the cell cycle arrest and apoptosis effect of the ES antigen towards the CRC cell line.
    MeSH terms: Animals; Cell Survival*; Chromatography, Liquid; Humans; Mass Spectrometry; Ascaris lumbricoides*; HCT116 Cells
  3. Identification of potential SARS-CoV-2 Nsp1 inhibitors from Piper sarmentosum Roxb. using molecular docking
    Saw KC, Ahmad Mokhtar AM, Ismail NI
    Trop Biomed, 2024 Jun 01;41(2):166-175.
    PMID: 39154269 DOI: 10.47665/tb.41.2.006
    Nsp1 in SARS-CoV-2 is a key protein that increases the virus's pathogenicity and virulence by binding to the host ribosome and blocks the 40S ribosomal subunit channel, which effectively impedes the mRNA translation as well as crippling the host immune system. Previous studies revealed that the N-terminal in Nsp1 is part and parcel of Nsp1 efficiency, and mutations in its core residues have weakened the protein's. This knowledge persuades us to carry out the in silico screening on plant compounds of Piper sarmentosum Roxb. against the five target residues which are Glu36, Glu37, Arg99, Arg124 and Lys125. Potential compounds were tested for their druggability. As a result, we identified five out of 112 compounds including stigmasterol, N-feruloyltyramine, beta-Sitosterol, 13-(1,3-benzodioxol-5-yl)- N-(2methylpropyl) trideca-2,4,12-trienamide and N-(2-methylpropyl) octadeca-2-4dienamide in Piper sarmentosum Roxb. as potential inhibitors for Nsp1. These compounds formed at least a hydrophobic, hydrogen bonding or π-cation interactions with the protein. Furthermore, SwissADME analysis and the number of bindings to the target residues suggest that N-feruloyltyramine is the ideal inhibitor candidate against SARS-CoV-2 at its N-terminal of Nsp1. Lastly, the interaction with N-feruloyltyramine increased flexibility in the loop regions of N-terminal Nsp1, especially residues 54 to 70, with residue 59 showing the highest fluctuation, potentially affecting the protein's stability and function due to the correlation between RMSF and protein function.
    MeSH terms: Antiviral Agents/pharmacology; Antiviral Agents/chemistry; Humans; Molecular Docking Simulation*
  4. Tick-borne pathogens isolated from ticks, rodents, and a shrew in Gangwon and Gyeonggi provinces in the Republic of Korea
    Choi YJ, Kim JY, Kang TU, Park HJ, Kim HC, Lee IY, et al.
    Trop Biomed, 2024 Jun 01;41(2):176-182.
    PMID: 39154270 DOI: 10.47665/tb.41.2.007
    The prevalence of tick-borne pathogens (TBP), Orientia tsutsugamushi, Rickettsia and Borrelia spp. in wild small animals, namely wild rodents, is now widely investigated. This study is to present the prevalence and distribution of O. tsutsugamushi, Rickettsia and Borrelia spp. in wild small animals and ticks collected from Gyeonggi and Gangwon provinces, Republic of Korea (ROK) in 2014. A total of 131 wild small animals, rodents and shrews, and 2,954 ticks were collected from Gyeonggi and Gangwon provinces from May to November 2014. The wild small animals (KR1-9) and ticks (K1-17) were grouped in accordance with capture dates and locations. Among the wild small animals, a total of 393 tissues and blood samples were extracted from six selected small animal series (KR1-3, KR6-8). Also, each date and location-grouped ticks were identified for its species and pooled according to the stage of development. Molecular identification for Rickettsia, Orientia, and Borrelia species was performed using polymerase chain reaction (PCR). To detect TBPs among wild small animals and ticks, primer sets targeting the 56 kDa protein encoding gene of Orientia spp., outer membrane protein B gene (OmpB) of Rickettsia spp., and 5S-23S intergenic spacer region (IGS) gene of Borrelia spp. were used. Of the 393 wild small animals' blood and tissue samples, 199 (50.6%) were positive for Orientia spp., 158 (40.2%) were positive for Borrelia spp., and 55 (14.0%) were positive for Rickettsia spp. Moreover, a total of 14 tick pools (n = 377) was positive for Rickettsia spp. (n=128, 34.0%) and Borrelia spp. (n=33, 8.8%). High prevalence of Orientia spp. and Rickettsia spp. in rodents and shrews were observed. This study presents significant insights by presenting data collected in 2014 that the prevalence of TBP was already high in mid 2010s. This study highlights the sustainable routine surveillance model for TBP.
    MeSH terms: Animals; Animals, Wild/microbiology; Animals, Wild/parasitology; Scrub Typhus/microbiology; Scrub Typhus/epidemiology; Scrub Typhus/veterinary; Polymerase Chain Reaction; Tick-Borne Diseases/microbiology; Tick-Borne Diseases/epidemiology; Tick-Borne Diseases/veterinary; Republic of Korea/epidemiology
  5. Sequence analysis and molecular characterization of low pathogenic avian influenza H9N2 virus isolated from chickens in Sabah
    Shohaimi SA, Leow BL, Mohd Yusop FF, Sidik MR, Barker Z, Mohd Saeid FH
    Trop Biomed, 2024 Jun 01;41(2):183-189.
    PMID: 39154271 DOI: 10.47665/tb.41.2.008
    Low pathogenic avian influenza (LPAI) subtype H9N2 is a causative agent that has raised increasing concern about its impact on poultry and potential public health threats. Even though H9N2 is endemic in Peninsular Malaysia, it was first reported in Sabah in August 2022, after an outbreak associated with high mortality in broiler chickens. In the present study, based on the hemagglutinin (HA) gene, we report the genetic variations and phylogenetic analysis of a H9N2 virus isolated from broiler chickens in Sabah. The sequence analysis of the HA gene revealed a 98% similarity to the H9N2 virus recently isolated from China in 2018. The amino acids in the HA cleavage site displayed a characteristic LPAI motif (PARSSR/ GLF). Notably, at position 226, the isolate had amino acid Leucine (L) demonstrating its ability to bind to the receptor of mammals, resulting in the potential risk of transmission to humans. In addition, the H9N2 isolate harboured seven potential N-glycosylation sites. The phylogenetic analysis revealed that the isolate belonged to clade h9.4.2.5 in the Y280 lineage, similar to previously reported in Malaysia. However, we observed that the isolate in this study falls in a different cluster compared with previous Malaysian isolates, suggesting different source of H9N2 introduction into the country. This prompts us to propose continuous and thorough surveillance of poultry across the country and the necessity of implementing farm biosecurity to minimize economic losses and potential threats to public health.
    MeSH terms: Animals; Chickens*; Malaysia; Phylogeny*; Genetic Variation; Hemagglutinin Glycoproteins, Influenza Virus/genetics
  6. Inhibition of Plasmodium knowlesi merozoite invasion into human erythrocytes by antibodies raised against the parasite's secreted protein with altered thrombospondin repeat (SPATR)
    Azlan UW, Cheong FW, Lau YL, Fong MY
    Trop Biomed, 2024 Jun 01;41(2):190-195.
    PMID: 39154272 DOI: 10.47665/tb.41.2.009
    The Plasmodium secreted protein with an altered thrombospondin repeat (SPATR) has been known to play an important role in the malaria parasite's invasion into host erythrocytes. This protein is immunogenic and has been considered as one of the potential vaccine candidates against malaria parasite infection. Thus far, only a handful immunological studies have been carried out on P. knowlesi SPATR (PkSPATR), and none of these studies investigated the immunoprotective properties of the protein. In the present study, the ability of anti-PkSPATR antibodies to inhibit invasion of human erythrocytes was assessed in an in vitro merozoite invasion inhibition assay. The antibodies were harvested from the serum of a rabbit which was immunised with recombinat PkSPATR. Results from the merozoite invasion inhibition assay revealed significant antibody invasion inhibitory activity in a concentration dependent manner (concentration range: 0.375 - 3.00 mg/ml) with inhibition rate ranging from 20% to 32%. Future studies, such as anti-PkSPATR antibodies inhibitory effect on sporozoite invasion of human liver cells, need to be carried out to assess the potential of PkSPATR as a knowlesi malaria vaccine candidate.
    MeSH terms: Animals; Humans; Rabbits; Malaria Vaccines/immunology; Thrombospondins/immunology
  7. Anthelmintic activity and pathophysiological effect of anthelmintic drugs against carcinogenic liver fluke, Opisthorchis viverrini
    Sangkam W, Arunsan P, Pechdee P, Boonsuya A, Thanchonnang C, Chatdumrong W, et al.
    Trop Biomed, 2024 Jun 01;41(2):196-205.
    PMID: 39154273 DOI: 10.47665/tb.41.2.010
    Human liver fluke, Opisthorchis viverrini poses a significant risk for development of cholangiocarcinoma (CCA) in Thailand, primarily attributed to consumption of undercooked cyprinoid fishes. The current use of anthelmintic drug treatment such as praziquantel (PZQ), as the main therapeutic agent against O. viverrini. There is a need to explore the efficacy of alternative anthelmintic drugs for O. viverrini treatment. This study aimed to assess the efficacy of anthelmintic drugs, which are commonly use in endemic areas of Southeast Asian countries; PZQ, albendazole (AL), niclosamide (NI), and mebendazole (ME) at concentrations of 600, 400, 500, and 500 mg/ml. The study included a negative and positive control group treated with roswell park memorial institute (RPMI) and PZQ. Reactive oxygen species (ROS) levels, indicative of oxidative stress, were quantified using 2',7'-dichlorofluorescein diacetate staining. Morphological changes were observed using scanning electron microscopy. Furthermore, motility assessments were conducted at various time points (0, 5, 30 minutes, 1, 3, 6, 12, and 24 hours), calculating relative motility (RM) and survival index (SI). The results revealed a significant increase of ROS levels with the intensity and corrected total worm fluorescence (CTWF) mostly observed in order of PZQ, followed by NI, ME, and AL, respectively. Morphological damage was presented the tegumental swelling, papillae changes, and disruption of microvilli (Mv), particularly in the group treated with the most effective anthelmintics PZQ, NI, ME, and AL, while negative control group did not exhibit such alterations. Also, the most efficacy for suppressing the motility of adult worms were displayed in PZQ treatment group, followed by NI, ME, and AL, respectively. Overall, first novel findings suggest that apart from NI, ME, and AL demonstrate potential as alternative therapeutic options for O. viverrini infection. Furthermore, animal model is needed to investigate the efficacy of NI, ME, and AL compare with standard treatment.
    MeSH terms: Animals; Mebendazole/pharmacology; Praziquantel/pharmacology; Thailand; Oxidative Stress/drug effects
  8. Campylobacter jejuni bacteremia in a leukemic child: a nearly missed diagnosis
    Ding CH, Wahab AA, Tzar MN, Mokhtar MN, Arunasalam V
    Trop Biomed, 2024 Jun 01;41(2):206-208.
    PMID: 39154274 DOI: 10.47665/tb.41.2.011
    Globally, Campylobacter spp. are responsible for most cases of bacterial gastrointestinal infections in humans and although rare, extraintestinal Campylobacter infections have been described. A 2-yearold neutropenic girl with underlying precursor B-cell acute lymphoblastic leukemia presented with a 3-day history of diarrhea. Her stool culture yielded no enteric bacterial pathogens. However, when her blood culture was flagged as positive for bacterial growth, no colonies could be observed on routine bacteriological isolation media. Nonetheless, gram-negative bacilli with seagull and spiral morphologies were seen when the surface of the isolation media used to subculture her blood was Gram-stained. Bacterial colonies were only visible when a subculture was attempted on a Campylobacter blood-free selective agar medium. The organism was identified as Campylobacter jejuni by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Since the organism was erythromycin-resistant and the patient's age precluded the use of tetracycline and ciprofloxacin, an antibiotic regimen consisting of piperacillin-tazobactam and gentamicin was commenced. Her C. jejuni bacteremia resolved following eight days of antibiotic therapy.
    MeSH terms: Child, Preschool; Female; Humans; Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/diagnosis; Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/drug therapy; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
  9. Development and validation of a PCR-based method to differentiate human sex in blood-fed Aedes aegypti (Diptera: Culicidae)
    Rathod L, Mishra S, Samuel S, Yadav K, Sharma G, Singh S, et al.
    Trop Biomed, 2024 Jun 01;41(2):209-213.
    PMID: 39154275 DOI: 10.47665/tb.41.2.012
    Monitoring mosquito host choice to identify high-risk groups for different vector-borne diseases is important to devise vector control strategies and disease management. The present study was conducted to develop and validate a PCR-based method to identify human sex in blood-fed Aedes aegypti mosquitoes. Several human genes present in both the X and Y chromosomes were screened and diagnostic PCR primers were successfully designed and amplified for the human STS gene. The limit of detection of this PCR assay was carried out on Ae. aegypti fed with human blood up to 5 days (120 hours) post blood-meal under laboratory condition. The efficiency of this PCR assay was evaluated in field-collected Ae. aegypti mosquitoes and compared with other existing methods. The developed PCR primers can successfully amplify and distinguish human sex in mosquitoes up to 72 hours after a blood meal, with an amplified product of 627bp and 298bp for male (XY) and 627bp for female (XX) blood-fed mosquitoes. Further, validation of this assay in field-collected Ae. aegypti mosquitoes revealed that this assay could detect human sex in mosquito blood meal substantially more efficiently (c2 = 4.5, p = 0.034) than other PCR based assay. The newly developed PCR assay highly specific to human DNA and can distinguish male and female DNA for up to 72 hours. This assay can be is used for identifying highrisk groups and extended to other medically important hematophagous insects to assess their role in disease transmission and epidemic preparedness.
    MeSH terms: Animals; Blood; Feeding Behavior; Female; Humans; Male; Mosquito Vectors/genetics
  10. Comparative analysis of natural resistance-associated macrophage protein 1 gene expression and anti-PGL-1 antibodies in multibacillary leprosy and household contacts
    Srihartati E, Agusni I, Listiawan Y
    Trop Biomed, 2024 Jun 01;41(2):214-219.
    PMID: 39154276 DOI: 10.47665/tb.41.2.013
    Leprosy continues to pose a significant challenge to public health, particularly in certain global regions. Accurate diagnosis and understanding of the disease's etiology are crucial for effective management and prevention. This study aimed to explore the contribution of Natural resistance-associated macrophage protein 1 (NRAMP1) and its genetic variations, as well as the levels of anti-PGL-1 antibodies, to the pathology of multibacillary leprosy in affected individuals and their household contacts. The study included 23 multibacillary leprosy patients and 28 household contacts. NRAMP1 protein expression and anti-PGL-1 IgG and IgM levels were measured using PCR and ELISA techniques, respectively. Genotypic variants of the NRAMP1 gene were also examined. Statistical analyses, including Mann-Whitney tests and univariate logistic regression, were employed to evaluate the data. Significant differences were observed in NRAMP1 protein expression and IgG and IgM levels between the patient and household contact groups. The study also highlighted the role of the NRAMP1 gene and its D543N and 3'UTR polymorphisms in leprosy susceptibility. No significant differences were observed in the genotype variants of INT4 between the two groups. These findings emphasize the potential of integrating PCR technology with serological tests to enhance diagnostic precision in leprosy. They also suggest the need for further research to clarify the role of NRAMP1 and its polymorphisms in leprosy susceptibility and resistance.
    MeSH terms: Adolescent; Adult; Family Characteristics; Female; Genotype; Glycolipids*; Humans; Immunoglobulin G/blood; Male; Middle Aged; Mycobacterium leprae/genetics; Mycobacterium leprae/immunology; Gene Expression; Young Adult
  11. Novel Vibrio vulnificus sequence type 540 infection in a hepatitis patient
    Chua HS, Soh YH, Ibrahim S, Abdullah NH, Che Mat Seri NAA, AbuBakar S, et al.
    Trop Biomed, 2024 Jun 01;41(2):220-223.
    PMID: 39154277 DOI: 10.47665/tb.41.2.014
    Vibrio vulnificus infection is associated with high morbidity and mortality in high-risk patients. Poor prognoses could lead to >50% mortality rate. The present report describes a case of V. vulnificus bacteremia in a cirrhotic patient with underlying hepatitis C. He presented with generalised abdominal pain associated with distention and could not ambulate for one week. He also complained of fever for six days and pruritus for 10 days. Tea-coloured urine was noted in continuous bag drainage. The abdomen was distended but soft, with mild tenderness palpated over the left lumbar and iliac region. Blood investigation indicated ongoing infection and inflammation. The aerobic blood culture was identified using the matrix-assisted laser desorption/ionisation-time of flight mass spectrometry and confirmed via 16S rDNA sequencing as V. vulnificus. Multilocus sequence typing of the isolated V. vulnificus revealed a novel sequence type, ST540. The patient responded well to the intravenous cefoperazone and was then discharged with a four day-course of oral ciprofloxacin, 500 mg twice daily after completing the intravenous cefoperazone for 10 days. Clinical history and physical examination are important for early antibiotic therapy initiation and appropriate surgical intervention. Furthermore, bacterial strain typing is also essential for epidemiological surveillance and potentially anticipating the pathogen's virulence traits, which are vital in controlling and preventing the spread of infection.
    MeSH terms: Anti-Bacterial Agents/therapeutic use; Hepatitis C/complications; Humans; Liver Cirrhosis/complications; Male; RNA, Ribosomal, 16S/genetics; Bacteremia/microbiology; Multilocus Sequence Typing
  12. Seroprevalences and their associated predictors of chikungunya, dengue, Japanese encephalitis and zika among forest fringe dwellers of Peninsular Malaysia
    Khor CS, Lee HY, Abd-Majid MA, Khoo HY, Khoo JJ, AbuBakar S
    Trop Biomed, 2024 Jun 01;41(2):224-229.
    PMID: 39154278 DOI: 10.47665/tb.41.2.015
    Serological evidence has shown the presence of several mosquito-borne arbovirus infections among the inhabitants of the forest fringe areas of the tropics. Among these infections, Japanese encephalitis, dengue fever, chikungunya fever and Zika fever could be targeted for vaccination to overcome severe infection and limit the disease transmission. Seroprevalence data among this high-risk population are needed to provide an estimate of the potential cost-effectiveness of any vaccine programme targeting these infections. The present study was conducted at six indigenous people (Orang Asli) villages and FELDA (Federal Land Development Authority) settlements located at the forest fringes of Malaysia. All participants consented and provided blood samples and demographic data for the study. The blood samples were tested for the presence of antibodies against CHIKV, DENV, JEV and ZIKV individually using ELISA. Results obtained were also analysed to determine the predictors for CHIKV, DENV, JEV and ZIKV seropositivity. Among the 585 samples tested, 33.0% (N=193), 41.7% (N=244), 10.3% (N=60) and 21.0% (N=123) were positive for CHIKV IgG, DENV IgG, JEV IgG and ZIKV IgG, respectively. Approximately one-third (N=220, 37.6%) of the participants were tested negative for IgG antibodies against all four arboviruses. Age of participants and type of settlement were found to be a significant predictor for CHIKV, DENV, JEV and ZIKV seropositivity. Level of education was a significant predictor for CHIKV, DENV and ZIKV seropositivity. Gender, however, was not found to be a significant predictor for infection with any of these viruses. These findings reaffirmed the significant presence of infection involving these major arboviruses among the group of people living within the forest fringe areas of Peninsular Malaysia. Hence, any future consideration of vaccination for these infections must take into consideration the marginalized and underserved communities living at the forest fringe areas of the tropics where these infections are present.
    MeSH terms: Adolescent; Adult; Aged; Child; Child, Preschool; Female; Humans; Immunoglobulin G/blood; Malaysia/epidemiology; Male; Middle Aged; Seroepidemiologic Studies; Young Adult; Forests
  13. Effect of diacylglycerol on partial coalescence of aerated emulsions: Fat crystal-membrane interaction and air-liquid Interface interaction insights
    Xie P, Zheng Y, Lee YY, Zou S, Wu Y, Lai J, et al.
    Food Chem, 2024 Aug 13;461:140879.
    PMID: 39154466 DOI: 10.1016/j.foodchem.2024.140879
    Currently, the poor whipping capabilities of anhydrous milk fat (AMF) in aerated emulsion products are a major obstacle for their use in beverages like tea and coffee, as well as in cakes and desserts, presenting fresh hurdles for the food industry. In this study, the mechanism of action of diacylglycerols (DAGs) with different carbon chain lengths and degrees of saturation on the partial coalescence of aerated emulsions was systematically investigated from three fundamental perspectives: fat crystallization, air-liquid interface rheology, and fat globule interface properties. The optimized crystallization of long carbon chain length diacylglycerol (LCD) based on stearate enhances interactions between fat globules at the air-liquid interface (with an elastic modulus E' reaching 246.42 mN/m), leading to a significantly reduced interface membrane strength. This promotes fat crystal-membrane interactions during whipping, resulting in a thermally stable foam structure with excellent shaping capability due to enhanced partial coalescence of fat globules. Although Laurate based medium carbon chain length diacylglycerol (MCD) promoted fat crystallization and optimized interface properties, it showed weaker foam properties because it did not adequately encapsulate air bubbles during whipping. Conversely, oleate long carbon chain length diacylglycerol (OCD) proved to be ineffective in facilitating fat crystal-membrane interaction, causing foam to have a subpar appearance. Hence, drawing from the carefully examined fat crystal-membrane interaction findings, a proposed mechanism sheds light on how DAGs impact the whipping abilities of aerated emulsions. This mechanism serves as a blueprint for creating aerated emulsions with superior whipping capabilities and foam systems that are resistant to heat.
  14. Lack of Blinding May Affect Objective Outcomes in Trials on Neonatal Ventilation
    Bruschettini M, Schmölzer GM, Lai NM, Mitra S, Davis PG, Soll RF
    Neonatology, 2024;121(6):791-792.
    PMID: 39154644 DOI: 10.1159/000540604
  15. Electrovalent effects of sodium carboxymethyl cellulose and hydroxyethyl cellulose on regeneration of empty fruit bunch cellulose to A superabsorbent hydrogel
    Salleh KM, Zakaria S, Armir NAZ, Khairunnisa-Atiqah MK, Wang B
    Int J Biol Macromol, 2024 Aug 16.
    PMID: 39154673 DOI: 10.1016/j.ijbiomac.2024.134816
    The hydrogel regeneration process, involving various cellulose types, results in distinct chemical bonding patterns. Even minor variations in chemical interactions among polymers during regeneration significantly impact properties like hydrogel-forming ability, hydrophilicity, and swelling capacity. This study focuses on regenerating a superabsorbent hydrogel from the interplay of native empty fruit bunch cellulose (EFBC), sodium carboxymethyl cellulose (NaCMC), and hydroxyethyl cellulose (HEC) using epichlorohydrin (ECH) as a crosslinker. The hydrogel was formed from dissolved EFBC solutions in an aqueous NaOH/urea solvent, supplemented with different NaCMC and HEC weight ratios, and ECH chemically assisted the crosslinking process. EFBC provides the hydrogel's supporting skeletal structure, while NaCMC and HEC play vital roles in enhancing forming ability and its physical and mechanical properties through diverse chemical interactions based on their electrovalent properties. Notably, NaCMC imparts hydrophilicity, while HEC indirectly improves superabsorbent properties through the enhancement of the elastic network's retraction force. Hydrogels combining NaCMC and HEC show a remarkable water absorption capacity exceeding 30,000 %, surpassing those regenerated solely with EFBC and NaCMC. The highest swelling, over 130,000 %, is achieved with 0.75 % NaCMC and 0.25 % HEC. Regarding thermal stability, hydrogels with a higher NaCMC proportion outperform those with increased HEC content. The study highlights the critical role of tailored chemical interactions in successfully regenerating an improved superabsorbent hydrogel with enhanced water absorption properties.
  16. A comprehensive review on the enantiomeric separation of chiral drugs using metal-organic frameworks
    Abbas A, Ahmad MS, Cheng YH, AlFaify S, Choi S, Irfan RM, et al.
    Chemosphere, 2024 Aug 16;364:143083.
    PMID: 39154761 DOI: 10.1016/j.chemosphere.2024.143083
    Chiral drugs play an important role in modern medicine, but obtaining pure enantiomers from racemic mixtures can pose challenges. When a drug is chiral, only one enantiomer (eutomer) typically exhibits the desired pharmacological activity, while the other (distomer) may be biologically inactive or even toxic. Racemic drug formulations introduce additional health risks, as the body must still process the inactive or detrimental enantiomer. Some distomers have also been linked to teratogenic effects and unwanted side effects. Therefore, developing efficient and scalable methods for separating chiral drugs into their pure enantiomers is critically important for improving patient safety and outcomes. Metal-organic frameworks (MOFs) show promise as novel materials for chiral separation due to their highly tunable structures and interactions. This review summarizes recent advancements in using MOFs for chromatographic and spectroscopic resolution of drug enantiomers. Both the opportunities and limitations of MOF-based separation techniques are discussed. A thorough understanding of these methods could aid the continued development of pure enantiomer formulations and help reduce health risks posed by racemic drug mixtures.
  17. Enhancing early warning: A DNA biosensor with polyaniline/graphene nanocomposite for label-free voltammetric detection of saxitoxin-producing harmful algae
    Chwan Chuong Chin JJ, Akbar MA, Mohd Yusof NY, Pike A, Goh CT, Mustapha S, et al.
    Chemosphere, 2024 Aug 20;364:143114.
    PMID: 39154772 DOI: 10.1016/j.chemosphere.2024.143114
    Yearly reports of detrimental effects resulting from harmful algal blooms (HAB) are still received in Malaysia and other countries, particularly concerning fish mortality and seafood contamination, both of which bear consequences for the fisheries industry. The underlying reason is the absence of a dependable early warning system. Hence, this research aims to develop a single DNA biosensor that can detect a group of HAB species known for producing saxitoxin (SXT), which is commonly found in Malaysian waters. The screen-printed carbon electrode (SPCE)-based DNA biosensor was fabricated by covalent grafting of the 3' aminated DNA probe of the sxtA4 conserved domain in SXT-producing dinoflagellates on the reverse-phase polymerized polyaniline/graphene (PGN) nanocomposite electrode via carbodiimide linkage. The introduction of a carboxyphenyl layer to the PGN nanotransducing element was essential to augment the carboxylic groups on the graphene (RGO), facilitating attachment with the aminated DNA. The synergistic effect of the asynthesized nanocomposite of PANI and RGO, tremendously enhanced the electron transfer rate of the ferri/ferrocyanide redox probe at the SPCE transducer surface, allowing for the label-free bioanalytical assay of complementary DNA targets. The developed DNA biosensor featuring the capacity to detect a broad range of Alexandrium minutum (A. minutum) cell concentrations, ranging from 10 to 10,000,000 cells L-1. The quantification of A. minutum cells from pure algal culture by the electrochemical DNA biosensor has been well-validated with traditional microscopic techniques. Furthermore, Alexandrium tamiyavanichii, another toxigenic HAB species, exhibited a similar electrochemical characteristic signal to those observed with A. minutum, whilst the biosensor yielded appreciably distinctive results when subjected to a non-toxigenic microalgae species as a negative control, i.e. Isochrysis galbana. A compendium DNA biosensor design and electrochemical detection strategy at laboratory scale serves as a precursor to the potential development of portable device for on-site detection, thus expanding the utility and scope of biosensor technology.
  18. Unlocking the possibilities of therapeutic potential of silymarin and silibinin against neurodegenerative Diseases-A mechanistic overview
    Ashique S, Mohanto S, Kumar N, Nag S, Mishra A, Biswas A, et al.
    Eur J Pharmacol, 2024 Oct 15;981:176906.
    PMID: 39154829 DOI: 10.1016/j.ejphar.2024.176906
    Silymarin, a bioflavonoid derived from the Silybum marianum plant, was discovered in 1960. It contains C25 and has been extensively used as a therapeutic agent against liver-related diseases caused by alcohol addiction, acute viral hepatitis, and toxins-inducing liver failure. Its efficacy stems from its role as a potent anti-oxidant and scavenger of free radicals, employed through various mechanisms. Additionally, silymarin or silybin possesses immunomodulatory characteristics, impacting immune-enhancing and immune-suppressive functions. Recently, silymarin has been recognized as a potential neuroprotective therapy for various neurological conditions, including Parkinson's and Alzheimer's diseases, along with conditions related to cerebral ischemia. Its hepatoprotective qualities, primarily due to its anti-oxidant and tissue-regenerating properties, are well-established. Silymarin also enhances health by modifying processes such as inflammation, β-amyloid accumulation, cellular estrogenic receptor mediation, and apoptotic machinery. While believed to reduce oxidative stress and support neuroprotective mechanisms, these effects represent just one aspect of the compound's multifaceted protective action. This review article further delves into the possibilities of potential therapeutic advancement of silymarin and silibinin for the management of neurodegenerative disorders via mechanics modules.
    MeSH terms: Animals; Antioxidants/pharmacology; Antioxidants/therapeutic use; Humans; Oxidative Stress/drug effects
  19. COVID-19 IgG Antibodies Detection Based on CNN-BiLSTM Algorithm Combined with Fiber-Optic Dataset
    Alathari MJA, Mashhadany YA, Bakar AAA, Mokhtar MHH, Bin Zan MSD, Arsad N
    J Virol Methods, 2024 Aug 16.
    PMID: 39154936 DOI: 10.1016/j.jviromet.2024.115011
    The urgent need for efficient and accurate automated screening tools for COVID-19 detection has led to research efforts exploring various approaches. In this study, we present pioneering research on COVID-19 detection using a hybrid model that combines convolutional neural networks (CNN) with a bi-directional long short-term memory (Bi-LSTM) network, in conjunction with fiber optic data for SARS-CoV-2 Immunoglobulin G (IgG) antibodies. Our research introduces a comprehensive data preprocessing pipeline and evaluates the performance of four different deep learning (DL) algorithms: CNN, CNN-RNN, BiLSTM, and CNN-BiLSTM, in classifying samples as positive or negative for the COVID-19 virus. Among these, the CNN-BiLSTM classifier demonstrated superior performance on the training datasets, achieving an accuracy of 89%, a recall of 88%, a precision of 90%, an F1-score of 89%, a specificity of 90%, a geometric mean (G-mean) of 89%, and a receiver operating characteristic (ROC) of 96%. In addition, the achieved classification results were compared with those reported in the literature. The findings indicate that the proposed model has promising potential for classifying COVID-19 and could serve as a valuable tool for healthcare professionals. The use of IgG antibodies to detect the virus enhances the specificity and accuracy of the diagnostic tool.
  20. Fulltext Health-related Quality of Life in Children with Vernal Keratoconjunctivitis in Malaysia
    Khairil-Ridzwan KK, Lai YS, Fiona CLM, Shatriah I
    Korean J Ophthalmol, 2024 Oct;38(5):364-374.
    PMID: 39155135 DOI: 10.3341/kjo.2024.0048
    PURPOSE: There has been a lack of data on health-related quality of life (HRQoL) in children with vernal keratoconjunctivitis (VKC) from Southeast Asia. This study evaluated the levels (mean total score and subscales score) of HRQoL, comparing the VKC and normal children groups, and within the VKC severity groups.

    METHODS: A cross-sectional study was conducted in two tertiary hospitals, specifically the pediatric ophthalmology services at Hospital Selayang and Universiti Sains Malaysia, spanning from 2019 to 2020. Participants aged between 8 and 15 years were categorized into two groups: those diagnosed with VKC and healthy children serving as the control group. Each participant completed the Quality of Life in Children with Vernal Keratoconjunctivitis (QUICK) questionnaire, consisting of 16 questions, divided into two subscales: 12 questions focusing on symptoms and four questions for daily activities.

    RESULTS: A total of 240 children took part in the study, with 120 children diagnosed with VKC and another 120 in the control group. The mean age of participants with VKC was 11.21 ± 1.91 years, with a male predominance of 4:1 compared to female. Tearing (98.4%) and itchiness (98.3%) emerged as the most prevalent symptoms affecting HRQoL, while the most challenging activities were outdoor play (36.6%) and participation in recreational water activities (34.2%). The mean total score was significantly higher in the VKC group compared to the control group. Additionally, both the mean total score and all subscale scores were significantly higher in the severe type compared to the mild-moderate type.

    CONCLUSIONS: VKC significantly reduce the HRQoL among Malaysian children, and the negative impact increases with the disease severity.

    MeSH terms: Adolescent; Child; Cross-Sectional Studies; Female; Humans; Malaysia/epidemiology; Male; Quality of Life*; Surveys and Questionnaires
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