Browse publications by year: 2023

  1. Fulltext A new species of pit-viper from the Ayeyarwady and Yangon regions in Myanmar (Viperidae, Trimeresurus)
    Chan KO, Anuar S, Sankar A, Law IT, Law IS, Shivaram R, et al.
    Zookeys, 2023;1186:221-234.
    PMID: 38312859 DOI: 10.3897/zookeys.1186.110422
    In a genomic study by Chan and colleagues, pit-vipers of the Trimeresuruserythrurus-purpureomaculatus complex from the Ayeyarwady and Yangon regions in Myanmar were demonstrated to be a distinct species based on robust population genetic and species delimitation analyses. Here, we provide morphological characterizations and a formal description of those populations as a new species. The new species, Trimeresurusayeyarwadyensissp. nov., is most closely related to T.erythrurus and T.purpureomaculatus and shares morphological characteristics with both of those species. Some specimens of T.ayeyarwadyensissp. nov. have green dorsal coloration and no distinct dorsal blotches (a trait shared with T.erythrurus but not T.purpureomaculatus), while others have dark dorsal blotches (a trait shared with T.purpureomaculatus but not T.erythrurus). The distinct evolutionary trajectory of the new species, coupled with the lack of obvious morphological differentiation, represents a classic example of the cryptic nature of species commonly found in the Trimeresurus group of Asian pit-vipers and underscores the need for data-rich analyses to verify species' boundaries more broadly within this genus.
  2. Fulltext Invisibility in global health: A case for disturbing bioethical frameworks
    Alenichev A, Suwalowska H, Faure MC, Ng SH, Modlin C, Ambrogi I, et al.
    Wellcome Open Res, 2023;8:191.
    PMID: 38313470 DOI: 10.12688/wellcomeopenres.19346.2
    In recent years, the global health community has increasingly reported the problem of 'invisibility': aspects of health and wellbeing, particularly amongst the world's most marginalized and impoverished people, that are systematically overlooked and ignored by people and institutions in relative positions of power. It is unclear how to realistically manage global health invisibility within bioethics and other social science disciplines and move forward. In this letter, we reflect on several case studies of invisibility experienced by people in Brazil, Malaysia, West Africa and other transnational contexts. Highlighting the complex nature of invisibility and its interconnectedness with social, political and economic issues and trends, we argue that while local and targeted interventions might provide relief and comfort locally, they will not be able to solve the underlying causes of invisibility. Building from the shared lessons of case study presentations at an Oxford-Johns Hopkins Global Infectious Disease Ethics Collaborative (GLIDE), we argue that in dealing with an intersectional issue such as invisibility, twenty-first century global health bioethics could pursue a more 'disturbing' framework, challenging the narrow comforting solutions which take as a given the sociomaterial inequalities of the status quo. We highlight that comforting and disturbing bioethical frameworks should not be considered as opposing sides, but as two approaches working in tandem in order to achieve the internationally set global health milestones of providing better health and wellbeing for everyone. Insights from sociology, anthropology, postcolonial studies, history, feminist studies and other styles of critical reasoning have long been disturbing to grand narratives of people and their conditions. To rediscover the ethos of the WHO Alma Ata Declaration-a vision of "health for all by the year 2000"-these thinking tools will be necessary aids in developing cooperation and support beyond the narrow market logic that dominates the landscape of contemporary global health.
  3. Bovine anaplasmosis: A systematic review with meta-analysis on the global prevalence
    Trop Biomed, 2023 Dec 01;40(4):375-382.
    PMID: 38308823 DOI: 10.47665/tb.40.4.001
    Bovine anaplasmosis, caused by Anaplasma marginale, is a significant infectious disease affecting cattle populations globally. However, the prevalence and distribution of bovine anaplasmosis vary across regions, making it crucial to assess its global burden systematically. This study aims to provide a comprehensive understanding of the global prevalence of bovine anaplasmosis and synthesized data from diverse geographic regions. A literature search was conducted to identify all relevant published articles reporting the prevalence of bovine anaplasmosis and a total of 164 studies were found eligible for final systematic review and meta-analysis. Meta-analysis was conducted using meta package of R software and summary estimates of the prevalence were calculated. Meta-analysis of 129,851 samples from 42 countries was conducted and the overall estimated prevalence of bovine anaplasmosis was found to be 38% (100% CI = 33% - 42%). The prevalence was found to be higher in cattle (39.9%) in comparison to yaks (6.4%). Diagnosis using serology (40.2%) yielded a higher prevalence compared to molecular testing (38.3%) and blood smears (22.4%) methods. Additionally, there were significant differences in the prevalence of bovine anaplasmosis between different countries (p<0.05). This study will inform evidence-based strategies for control and prevention of bovine anaplasmosis on a global scale by discovering the true extent of the disease and identifying high-prevalence areas.
    MeSH terms: Animals; Cattle; Genetic Variation; Prevalence; Anaplasma marginale*
  4. Molecular identification of Opisthorchis viverrini among the northeastern Cambodian population by internal transcribed spacer 2 based polymerase chain reaction
    La N, Leng M, Arunsan P, Pechdee P, Boonsuya A, Thanchonnang C, et al.
    Trop Biomed, 2023 Dec 01;40(4):383-391.
    PMID: 38308824 DOI: 10.47665/tb.40.4.002
    The southeast Asian fluke Opisthorchis viverrini remains endemic, particularly in Thailand, Lao PDR, Cambodia, Vietnam, and Myanmar. However, there is a lack of data on the prevalence of liver fluke infection in Kratie Province in northeastern Cambodia. The present study aimed to detect O. viverrini DNA in fecal specimens by using the internal transcribed spacer 2 (ITS2) region of ribosomal DNA (rDNA) based on polymerase chain reaction (PCR). The prevalence and percentage of O. viverrini infection were described by data analysis. Bivariate binary logistic regression analysis was used to look at the related prevalence of O. viverrini infection. A total of 6.89% from 377 fecal samples were found positive of O. viverrini DNA. The prevalence of O. viverrini infection was found to be higher in men (8.92%) than in women (5.45%), and to be associated more frequently with younger age groups (13.40%), illiteracy (8.74%), participation in other careers (non-specific occupations) (11.63%), and residence in the Trapaing Srae village (9.94%) of the Snuol district, Kratie Province. Age groups under 20 years old were significantly linked with O. viverrini infection, with ORadj=0.601, 95% CI=0.410-0.882, p=0.009 and significant value established at (P<0.05). This study demonstrates that O. viverrini infection is distributed in rural areas located near freshwater reservoirs. Therefore, active surveillance, clinical examination of association with hepatobiliary, cholangiocarcinoma, and health education are needed.
    MeSH terms: Adult; Animals; Bile Ducts, Intrahepatic; Cambodia/epidemiology; DNA; Female; Humans; Male; Thailand/epidemiology; Polymerase Chain Reaction; Young Adult
  5. Wild hosts and microscopic worlds: Investigating the morphology and surface ultrastructure of Blastocystis sp. in avian and non-human primate species
    Sanggari A, Attah AO, Yahaya ZS, Farah Haziqah MT
    Trop Biomed, 2023 Dec 01;40(4):392-399.
    PMID: 38308825 DOI: 10.47665/tb.40.4.003
    Blastocystis is a prevalent infectious agent found in the gastrointestinal tract of humans and animals. While the morphology of Blastocystis has been extensively studied, there is still a lack of comprehensive research on its ultrastructure, especially regarding surface characteristics and their correlation with pathogenic potential. Additionally, the subtyping of Blastocystis does not provide information on the isolate's pathogenicity. This study aimed to examine the morphology and the cell surface of Blastocystis in avian and non-human primates, including peafowl, pheasant, and lion-headed tamarin. By employing light microscopy and scanning electron microscopy (SEM), this study provides the first evidence of the cellular and surface features of Blastocystis in these animal species. Our findings revealed distinct variations in cell size, shape, and surface morphology among the different host species. Notably, the isolates from peafowl exhibited larger cell sizes compared to the isolates from the pheasant. However, interestingly, both animal species were found to exhibit the same Blastocystis ST6. It was also observed that the surface structure of Blastocystis from different hosts displayed a diverse range of patterns, including mesh-like appearances, deep indentations, and attachments to bacteria. Additionally, findings also revealed the presence of a rough surface structure in peafowl, a characteristic that has been previously linked to pathogenicity and symptomatic infection in animals, as indicated by earlier studies. The findings contribute to our understanding of the morphological features and the surface characteristic of Blastocystis in different host species, shedding light on the parasite's adaptations and potential implications for host health.
    MeSH terms: Animals; Feces; Humans; Microscopy, Electron, Scanning; Primates; Blastocystis*
  6. A non-toxic recombinant protein rSUMO-CPBm4 as a potential vaccine candidate against Clostridium perfringens type C beta enterotoxemia
    Goa Y, Du JG, Jirapattharasate C, Galon E, Ji SW, Ran ZG, et al.
    Trop Biomed, 2023 Dec 01;40(4):400-405.
    PMID: 38308826 DOI: 10.47665/tb.40.4.004
    Beta toxin (CPB) is a lethal toxin and plays a key role in enterotoxemia of ruminants caused by Clostridium perfringens type C strain. The existing vaccines based on crude CPB need time-consuming detoxification and difficult quality control steps. In this study, we synthesized the rCPBm4 of C. perfringens type C strain and small ubiquitin-like modifier (SUMO)-tag CPBm4 (rSUMO-CPBm4) by introducing four amino acid substitutions: R212E, Y266A, L268G, and W275A. Compared with rCPBm4, rSUMO-CPBm4 was expressed with higher solubility in Escherichia coli BL21 (DE3). Neither rCPBm4 nor rSUMO-CPBm4 was lethal to mice. Although rCPBm4 and rSUMO-CPBm4 were reactogenic with polyclonal antibodies against crude CPB, rabbits vaccinated with rSUMO-CPBm4 developed significant levels of toxin-neutralizing antibody (TNA) titers that conferred protection against crude toxin challenge. These data suggest that genetically detoxified rSUMO-CPBm4 is a promising subunit vaccine candidate for C. perfringens type C beta enterotoxemia.
    MeSH terms: Animals; Bacterial Vaccines; Clostridium perfringens/genetics; Enterotoxemia/prevention & control; Rabbits; Recombinant Proteins/genetics; Mice
  7. Cerebrospinal fluid inflammatory cytokine profiles of patients with neurotropic parasitic infections
    John DV, Sreenivas N, Deora H, Purushottam M, Debnath M, Mahadevan A, et al.
    Trop Biomed, 2023 Dec 01;40(4):406-415.
    PMID: 38308827 DOI: 10.47665/tb.40.4.005
    The pathogenesis of chronic parasitic central nervous system (CNS) infections, including granulomatous amoebic meningoencephalitis (GAE), cerebral toxoplasmosis (CT), and neurocysticercosis (NCC), is primarily due to an inflammatory host reaction to the parasite. Inflammatory cytokines produced by invading T cells, monocytes, and CNS resident cells lead to neuroinflammation which underlie the immunopathology of these infections. Immune molecules, especially cytokines, can therefore emerge as potential biomarker(s) of CNS parasitic infections. In this study, cerebral spinal fluid (CSF) samples from suspected patients with parasitic infections were screened for pathogenic free-living amoebae by culture (n=2506) and PCR (n=275). Six proinflammatory cytokines in smear and culture-negative CSF samples from patients with GAE (n = 2), NCC (n = 7), and CT (n = 23) as well as control (n = 7) patients were measured using the Multiplex Suspension assay. None of the CSF samples tested was positive for neurotropic free-living amoebae by culture and only two samples showed Acanthamoeba 18S rRNA by PCR. Of the six cytokines measured, only IL-6 and IL-8 were significantly increased in all three infection groups compared to the control group. In addition, TNFa levels were higher in the GAE and NCC groups and IL-17 in the GAE group compared to controls. The levels of IL-1b and IFNg were very low in all the infection groups and the control group. There was a correlation between CSF cellularity and increased levels of IL-6, IL-8, and TNFa in 11 patients. Thus, quantifying inflammatory cytokine levels in CSF might help with understanding the level of neuroinflammation in patients with neurotropic parasitic diseases. Further studies with clinico-microbiological correlation in the form of reduction of cytokine levels with treatment and the correlation with neurological deficits are needed.
    MeSH terms: Humans; Inflammation; Parasitic Diseases*; Interleukin-6*; Cytokines; Interleukin-8
  8. Two new records of chewing lice (Phthiraptera: Amblycera) from the Oriental honey buzzard [Pernis ptilorhynchus (Temminck, 1821)] and house crow (Corvus splendens Viellot, 1817) in Malaysia
    Kazim AR, Houssaini J, Tappe D, Heo CC, Vellayan S
    Trop Biomed, 2023 Dec 01;40(4):416-421.
    PMID: 38308828 DOI: 10.47665/tb.40.4.006
    We report two new records of chewing lice from avian pets in Peninsular Malaysia: Colpocephalum apivorus Tendeiro, 1958 from an Oriental honey buzzard (Pernis ptilorhynchus (Temminck, 1821)), and Myrsidea splendenticola Klockenhoff, 1973 from an albino house crow (Corvus splendens Vieillot, 1817). The scarcity of louse records from avian pets and wild birds, and the lack of louse research in Malaysia are discussed.
    MeSH terms: Animals; Bird Diseases*; Birds; Honey*; Malaysia; Crows*; Amblycera*; Ischnocera*
  9. Characterization of Campylobacter jejuni and Campylobacter coli isolates from chicken offal in Metro Manila, Philippines: Insights from virulence gene prevalence and multilocus sequence typing analysis
    Subejano MSE, Penuliar G
    Trop Biomed, 2023 Dec 01;40(4):422-429.
    PMID: 38308829 DOI: 10.47665/tb.40.4.007
    Campylobacteriosis is a human infection primarily caused by Campylobacter jejuni and Campylobacter coli. Consumption of contaminated chicken and poultry products is the main mode of transmission. These bacteria possess virulence factors, including adhesins and toxins, which contribute to their pathogenesis. Moreover, their large genomes undergo frequent genetic recombination, resulting in a high degree of genetic diversity. However, limited information is available regarding the virulence and genotypic diversity profiles of these microorganisms in the Philippines. The objective of this study was to address this knowledge gap by characterizing Campylobacter isolates obtained from chicken offal sold in wet markets in Metro Manila, Philippines. Multilocus Sequence Typing (MLST) analysis was performed to determine the sequence types, resulting in the identification of 13 unique sequence types, including nine previously unreported ones, and three clonal complexes. Notably, the widespread sequence type ST-305 was found in samples from different markets. Furthermore, six isolates deposited in the Campylobacter PubMLST database were identified as C. coli based on allele profiles. Profiling using 10 selected virulence genes revealed that more than half of the isolates carried these genes. The most prevalent virulence gene was cadF (100%), followed by flaA (95%), racR, cdtA, cdtB, and cdtC (85%). The genes dnaJ and ceuE were also present in 75% of the isolates. Despite the limited sample size, the findings of this study reveal a significant level of genotypic diversity among the Campylobacter isolates. This diversity has important implications for source attribution studies and the identification of strains involved in campylobacteriosis outbreaks. Furthermore, the investigation of virulence factors associated with colonization and invasion of the avian gut can provide insights for the development of practical applications in Campylobacter control strategies. Understanding and addressing these factors are crucial steps toward mitigating the risk of Campylobacter infections and enhancing public health efforts.
    MeSH terms: Animals; Chickens; Humans; Philippines/epidemiology; Virulence/genetics; Prevalence; Virulence Factors/genetics; Multilocus Sequence Typing
  10. Inhibition of choline kinase as an antiamoebic approach in Entamoeba histolytica infection
    Teh ZH, Lim BH, See Too WC, Few LL
    Trop Biomed, 2023 Dec 01;40(4):430-438.
    PMID: 38308830 DOI: 10.47665/tb.40.4.008
    Entamoeba histolytica is the parasite responsible for amoebiasis, which can result in amoebic colitis or amoebic liver abscess. Metronidazole has been the conventional treatment for intestinal amoebiasis, but concerns regarding resistance have emerged due to the identification of resistance pathways in E. histolytica. This study investigates a novel anti-amoebic approach targeting the CDP-choline pathway. Inhibition studies were conducted using potential choline kinase (CK) inhibitors to inhibit the EhCK enzyme, and RNA interference was employed to knock down the EhCK gene. Km and Vmax of purified EhCK and hCKa2 proteins were determined by pyruvate kinase-lactate dehydrogenase (PK-LDH) coupled assay. The IC50 values for EhCK and hCKa2 were determined with several commercial CK inhibitors. Selected inhibitors were incubated with E. histolytica trophozoites for 48 hours to determine the EC50 for each inhibitor. Silencing of gene encoding EhCK was carried out using duplex siRNA and the gene expression level was measured by real-time qPCR. Based on the IC50 values, three of the inhibitors, namely CK37, flavopiridol and H-89 were more potent against EhCK than hCKa2. Trophozoites growth inhibition showed that only HDTAB, H-89 and control drug metronidazole could penetrate and induce cell death after 48-hour incubation. siRNA concentration of 10 µg/mL was used for the transfection of positive control GAPDH, EhCK, and non-targeting GFP siRNAs. RNAi experiment concluded with positive control GAPDH downregulated by 99% while the level of EhCK mRNA was downregulated by 47%. In this study, potential inhibitors of EhCK and siRNA have been identified, paving the way for further refinement and testing to enhance their potency against EhCK while sparing hCK. The utilization of these specific inhibitors and siRNA targeting EhCK represents a novel approach to impede the growth of E. histolytica by disrupting its phospholipid synthesis pathway.
    MeSH terms: Amebiasis*; Choline Kinase/metabolism; Humans; Isoquinolines*; Metronidazole/pharmacology; Sulfonamides*; RNA, Small Interfering/metabolism
  11. Investigations of clinical characteristics and inflammatory markers of febrile seizures induced by coronavirus infection
    Zhao L, Wu HY, Xie D, Mo LM, Yang FF, Gao Y, et al.
    Trop Biomed, 2023 Dec 01;40(4):439-443.
    PMID: 38308831 DOI: 10.47665/tb.40.4.009
    The study of children who experienced with febrile seizures(FS) as a result of COVID-19 infection to gain insight into the clinical characteristics and prognosis of neurological damage, with the aim of improving prevention, diagnosis, and the treatment of neurological complications. This study investigated the clinical features of 53 children with FS who were admitted to Sanya Women and Children's Hospital from December 1, 2022, to January 31, 2023. The results indicated that the duration of convulsion in the case and control group was 7.90±8.91 and 2.67±1.23 (minutes) respectively. The analysis reveals that convulsions occurred within 24 hours in 39 cases (95.12%) of the case group, and in 8 cases (66.7%) of the control group. The difference was statistically significant (P<0.05). Additionally, the case group presented lower counts of WBC and NEU compared to the control group (p<0.05). The findings indicate that convulsions manifest at earlier stages of COVID-19 in children and the last longer than in the control group. It is therefore crucial for healthcare workers to remain attentive to patients with COVID-19 who report fever within 24 hours, and act promptly to implement preventive measures, particularly in cases of prolonged fever. It is essential to integrate the clinical manifestation, particularly convulsions, and the continuous numerical changes of inflammatory factors to assess COVID-19 linked with febrile seizures. In addition, larger-scale multi-center and systematic research are necessary to aid clinicians in monitoring neuropathological signals and biological targets, enabling more equitable diagnosis and treatment plans.
    MeSH terms: Child; Female; Fever; Humans; Infant
  12. Parasitic coinfections among selected smallholder goat flocks in Malaysia
    Paul BT, Jesse FAA, Kamaludeen J, Chung ELT, Mat Isa K, Azhar NA, et al.
    Trop Biomed, 2023 Dec 01;40(4):444-452.
    PMID: 38308832 DOI: 10.47665/tb.40.4.010
    This paper describes the occurrence of multiple parasitic infection with special reference to emerging haemotropic Mycoplasma ovis. A cross-sectional survey of four selected goat flocks was conducted to collect samples and management information. Blood samples were processed using microhaematocrit centrifugation to determine the packed cell volume (PCV). Detection and morphological identification of blood protozoa and haemotropic Mycoplasma ovis from Giemsa-stained smears were done microscopically. M. ovis infection was classified mild (1-29% infected cells), moderate (30-59% infected cells), or severe (above 60% infected cells). Faecal floatation and McMaster faecal egg count were used to detect and classify strongyle infections as negative (no eggs/oocysts), light (< 500 epg), Moderate (500 - 1000 epg), or severe (>1000 epg) and coccidia infection as light (<1800 opg), moderate (1800 - 6000 opg), or severe (>6000 opg). There were 149 goats with blood protozoa (57.98%; 95% CI: 51.87 - 63.85) and 204 goats with GI parasites (79.38%; 95% CI: 74.02 - 83.87) involved in single (15.8%; 95% CI: 11.7 - 21.0) or multiple (84.2%; 95% CI: 79.0 - 88.3) infections. The risk of Strongyles increases by 2.49 (95% CI: 1.24 - 4.99) in females versus males and 6.79 (95% CI: 3.25 - 14.18, p =0.000) in adults versus young. The risk of Eimeria species increases by 7.32 (95% CI: 3.45 - 15.50, p =0.000) in adults versus young, while M. ovis coinfection risk increases by 4.51 (95% CI: 1.40 - 14.50, p =0.000) in female versus males. Thin animals had a significantly higher (p<0.05) mean burden of Strongyle (1370.37 ± 345.49) and Eimeria (1594.12 ± 695.26) than the moderate and fat goats. The PCV was negatively associated with mean faecal egg count (FEC) (p<0.05) such that a lower PCV was recorded in animals with a higher Strongyle epg output. A severe burden of M. ovis was accompanied by an increased nematode FEC and decreased haematocrit (p<0.05). Coinfections of Strongyles, or Eimeria species involving M. ovis were associated with a higher parasitaemia compared with single infections (p<0.05). This study highlights the importance of M. ovis and Strongyle or Eimeria species coinfections among goat flocks and provides valuable data for developing and implementing an integrated herd health management program for parasite control among low-input smallholder flocks.
    MeSH terms: Animals; Cross-Sectional Studies; Feces/parasitology; Female; Goats/parasitology; Malaysia/epidemiology; Male; Mycoplasma*; Parasite Egg Count/veterinary; Parasites*; Sheep
  13. Elettaria cardamomum essential oil; immunomodulatory, antioxidant, and anti-inflammatory effects for controlling acute Toxoplasma gondii infection
    Abdullah DA, Aishah EA
    Trop Biomed, 2023 Dec 01;40(4):453-461.
    PMID: 38308833 DOI: 10.47665/tb.40.4.011
    The present study was conducted to investigate the immunomodulatory and anti-inflammatory effects of Elettaria cardamomum essential oil (ECEO) for the control of acute Toxoplasma gondii infection. The effect of ECEO on T. gondii tachyzoites was measured by the tetrazolium bromide method. Mice received ECEO orally at doses of 1-4 mg/kg/day for 14 days. Once acute toxoplasmosis was induced in mice, their mortality rate and parasite load were recorded. The level of liver antioxidant/oxidant enzymes and the level of mRNA expression of interleukin-1 beta and interferongamma were also investigated. ECEO particularly at a concentration of 150 µg/ml has promising in vitro anti-Toxoplasma effects (p<0.001). After treatment with ECEO, the mortality rate (9th day) and parasite load decreased (p<0.001) in the infected mice. ECEO markedly (p < 0.05) restored hepatic oxidant and antioxidant enzyme levels, as well as increased cytokines. These results report a significant inhibitory effect of ECEO mainly at a dose of 4 mg/mL, against the T. gondii Rh strain through strengthening the immune system and reducing inflammation and oxidative stress; however, further research is needed to verify these results.
    MeSH terms: Animals; Anti-Inflammatory Agents/pharmacology; Antioxidants/pharmacology; Toxoplasmosis*; Oxidants/pharmacology; Oxidants/therapeutic use; Elettaria*; Mice
  14. Bat coronavirus was detected positive from insectivorous bats in Krau Wildlife Reserve Forest
    Siew ZY, Lai ZJ, Ho QY, Ter HC, Ho SH, Wong ST, et al.
    Trop Biomed, 2023 Dec 01;40(4):462-470.
    PMID: 38308834 DOI: 10.47665/tb.40.4.012
    Bats are flying mammals with unique immune systems that allow them to hold many pathogens. Hence, they are recognised as the reservoir of many zoonotic pathogens. In this study, we performed molecular detection to detect coronaviruses, paramyxoviruses, pteropine orthoreoviruses and dengue viruses from samples collected from insectivorous bats in Krau Reserve Forest. One faecal sample from Rhinolophus spp. was detected positive for coronavirus. Based on BLASTN, phylogenetic analysis and pairwise alignment-based sequence identity calculation, the detected bat coronavirus is most likely to be a bat betacoronavirus lineage slightly different from coronavirus from China, Philippines, Thailand and Luxembourg. In summary, continuous surveillance of bat virome should be encouraged, as Krau Reserve Forest reported a wide spectrum of biodiversity of insectivorous and fruit bats. Moreover, the usage of primers for the broad detection of viruses should be reconsidered because geographical variations might possibly affect the sensitivity of primers in a molecular approach.
    MeSH terms: Animals; Animals, Wild; Chiroptera*; Phylogeny; Genome, Viral; Coronavirus Infections*
  15. Oral parasitic protozoan Entamoeba gingivalis in periodontal disease patients, northeastern Thailand
    Boonsuya A, Chitpitaklert P, Pechdee P, Srithongklang W, Thanchonnang C, La N, et al.
    Trop Biomed, 2023 Dec 01;40(4):471-477.
    PMID: 38308835 DOI: 10.47665/tb.40.4.013
    Entamoeba gingivalis is present in the oral cavity of humans and is associated with periodontal disease. Consequently, this study aimed to comprehensively investigate the E. gingivalis infection and the associated risk factors among individuals suffering from periodontal conditions. A cross-sectional descriptive study was carried out within a cohort of periodontal patients. Dental plaque specimens were meticulously collected and subsequently subjected to thorough examination using the polymerase chain reaction (PCR)-based technique targeting the small subunit ribosomal RNA (SrRNA) gene of the organism. The occurrence of risk factors for E. gingivalis infection was analyzed by the chi-square test and binary logistic regression. Out of the 230 participants, 60 were clinically diagnosed with periodontitis, while 170 were afflicted with gingivitis. Out of the 230 patients, 25 (10.9%) tested positive for E. gingivalis infections. An in-depth analysis unveiled that a significant majority of infections were recorded within subgroups characterized by a marital status (15.45%), manifestation of periodontitis (25.00%), and concomitant presence of underlying disease (20.83%). Furthermore, the high risk factor associated with E. gingivalis infection was the female (ORadj = 13.65, 95% CI = 1.08-173.21), followed by periodontitis (ORadj = 3.30, 95% CI = 1.21-9.00), respectively. The study employs a molecular diagnostic approach to screen for E. gingivalis enrichment within a subset of periodontal patients with advancing disease. The findings emphasize the necessity for further research to elucidate the pathogenesis of E. gingivalis and advocate for vigilant surveillance within a substantial population of periodontal patients.
    MeSH terms: Cross-Sectional Studies; Entamoeba*; Female; Humans; Thailand
  16. Stability of enteroviruses on toys commonly found in kindergarten
    Baharin SNAN, Tan SL, Sam IC, Chan YF
    Trop Biomed, 2023 Dec 01;40(4):478-485.
    PMID: 38308836 DOI: 10.47665/tb.40.4.014
    Hand, foot, and mouth disease (HFMD) is a contagious childhood disease caused by enteroviruses including enterovirus A71 (EV-A71), coxsackievirus A6 (CV-A6) and CV-A16 transmitted via direct and indirect contact. Different types of toy surfaces can affect the stability of viruses. Understanding the stability of enteroviruses on toys provides insightful data for effective disinfection in kindergartens or homes. Porous (ethylene-vinyl acetate mat foam, paper, pinewood, polyester fabric, and squishy polyurethane foam) and non-porous (acrylonitrile butadiene styrene plastic and stainless-steel coin) surfaces were inoculated with EV-A71 at 4, 24, and 35°C, and coxsackieviruses at 24°C. Infectious enteroviruses were recovered and titred in median tissue culture infectious dose assay (TCID50). Atomic force microscopy (AFM) images were taken from surfaces to examine association of surface roughness with virus stability. Overall, infectious enteroviruses were persistent on all non-porous and porous surfaces. Virus persistence was longest at 4°C followed by 24°C and 35°C. EV-A71 half-lives ranged between 6.4-12.8 hours at 4°C, 2.4-6.7 hours at 24°C, and 0.13-2.7 hours at 35°C. At lower virus titres exposed to 24°C, half-lives of enteroviruses ranged from 0.1-1.4 hours. Surface roughness values from AFM suggested smooth surfaces of non-porous surfaces were associated with better virus stability. Temperature, enterovirus concentration, and type of surface affected persistence and stability of enteroviruses. Our findings suggest both porous and non-porous surfaces in kindergartens allow enterovirus persistence and should be frequently disinfected to curb HFMD outbreaks in kindergartens.
    MeSH terms: Child; China/epidemiology; Disease Outbreaks; Enterovirus*; Humans; Enterovirus A, Human*
  17. New peperomin and polyketides from dichloromethane extract of Peperomia blanda Jack. (Kunth)
    Al-Madhagi WM, Sharhan O, Jadan B, Hashim NM, Awadh N, Othman R
    Trop Biomed, 2023 Dec 01;40(4):486-496.
    PMID: 38308837 DOI: 10.47665/tb.40.4.015
    Much of the new research and investigation in pharmacy sciences are concerned with developing therapeutic agents, and identifying and finding new drugs with their chemical structure to treat different human diseases such as infectious diseases from natural products. Therefore, the present findings relate to isolating five new compounds the dichloromethane extract of Peperomia blanda (Jacq.) Kunth grown on Socotra Island, Yemen. two new secolignans; which have been proposed as peperomin I & J. These compounds were isolated together with the other two polyketides presented as surinone D and dindygulerione F. The chemical structures were elucidated and confirmed with nuclear magnetic resonance (NMR) and liquid chromatography-mass spectroscopy (LCMS) analysis. These compounds were first isolated and reported from this plant. These new compounds' antimicrobial activity has been evaluated, and minimum inhibitory concentration has been recorded in the range of 125-250 µg/mL. The pharmacotherapeutic spectrum of compounds was predicated using PASS software which showed potential activity.
    MeSH terms: Biological Products*; Humans; Methylene Chloride; Plant Extracts/pharmacology
  18. Parasitic dinoflagellate Hematodinium in marine decapod crustaceans: a review on current knowledge and future perspectives
    Alimin AWF, Yusoff NAH, Kadriah IAK, Anshary H, Abdullah F, Jabir N, et al.
    Parasitol Res, 2023 Dec 14;123(1):49.
    PMID: 38095702 DOI: 10.1007/s00436-023-08067-z
    Parasitic dinoflagellates of the genus Hematodinium are known to infect various marine crustaceans worldwide, especially crabs and several species of shrimp and lobster. Some of these species are new host species and components of commercial fishery products. These parasitic species are predominantly found in the hemolymph of the host and cause pathological changes and functional damage to organs and tissues, leading to death. In recent years, these parasites have infected important commercially valuable species, particularly in European waters, US waters, Australian waters, and recently in Shandong Peninsula in China. These Hematodinium pathogens were also reported to affect wild shrimp in Chinese waters and in the English North Sea. These rapid spreads affect crustacean aquaculture industries, where they are indeed a significant threat to the sustainability of the aquaculture of important crustaceans. The fishery products industries are also under pressure from the invasion of this pathogen, as the crab meat produced has a bitter taste, which may reduce its marketability. In response to these threats, this review was aimed at providing a broader understanding of the development of parasite distribution and ecological aspects of Hematodinium. In addition, the interaction of these pathogens with their hosts, the environmental drivers of Hematodinium disease, and future research perspectives were discussed.
    MeSH terms: Animals; Australia; Seafood; Aquaculture
  19. Fulltext Diagnostic challenges of superficial mucoceles: An update
    Pandarathodiyil AK, Sivapathasundharam B
    J Oral Maxillofac Pathol, 2023;27(4):616-621.
    PMID: 38304527 DOI: 10.4103/jomfp.jomfp_470_23
    A superficial mucocele is a unique variant of a mucocele of the oral cavity that was described by Eveson for the first time in 1988. It occurs due to subepithelial extravasation of sialomucin at the epithelial-connective tissue interface and is related to damage of the minor salivary gland ducts. Clinically, they appear as small, asymptomatic, clear, tense vesicles with a predilection for the soft palate, retromolar pads, and posterior buccal mucosa. They are reported to occur more frequently in women than in men. Before Eveson endeavoured to describe these rather peculiar lesions, they were often misdiagnosed as vesiculobullous lesions such as bullous lichen planus, mucous membrane pemphigoid, and the like. It is incumbent on the present-day pathologist to be cognizant of the presence of these entities as it could present a formidable diagnostic challenge otherwise. This review gives an updated account on the etiology, prevalence, clinical features, differential diagnosis, and management of superficial mucoceles.
  20. Fulltext Exploring the Barriers and Expectations Towards Health Care Services Among Parents/Caretakers of People with Intellectual Disability in Kuantan, Malaysia: A Qualitative Study
    Mohd FN, Said AH, Ahmad MS, Ridzwan AN, Muhammad AI, Mat Naji AS
    J Int Soc Prev Community Dent, 2023;13(6):477-484.
    PMID: 38304533 DOI: 10.4103/jispcd.JISPCD_89_23
    BACKGROUNDS: People with intellectual disabilities (PWID) are often characterized by challenges in learning and difficulties in performing daily activities. These difficulties can have an impact not only on the individuals themselves but also on the people around them, especially their parents, caregivers, and healthcare workers. Therefore, establishing a positive relationship between parents or caregivers and individuals with disabilities is crucial as a key factor in promoting positive healthcare experiences and outcomes.

    AIM: This study aims to explore the barriers and perceptions toward healthcare services among parents or caretakers of people with intellectual disability, including the challenges and their expectations toward healthcare services.

    MATERIALS AND METHODS: This was a qualitative study using purposive sampling. Thirty participants were contacted at the initial stage and invited to participate in the study. Semi-structured in-depth interviews were done among parents and caretakers of PWID who attended Special Care Dentistry and Paediatric Dentistry clinics in Sultan Ahmad Shah Medical Centre, Kuantan, Pahang. Topic guides were generated from literature review and expert opinions, followed by pilot interviews to refine them. However, after the interviews were done for the first 13 participants, we have reached data saturation, and no new themes emerged. The interviews were recorded, verbatim transcribed, and analyzed using Braun and Clarke's guidelines for thematic analysis.

    RESULTS: The satisfaction of parents or caretakers toward healthcare services for PWID and positive experiences in receiving healthcare services were noted. However, the results revealed several barrier themes in seeking healthcare services: lack of availability of parking, longer waiting time, appointment time, crowded environment, limited information on the availability of the services, and longer travel duration. Furthermore, expectation themes emerged from this study: continuous follow-up, accessibility to healthcare services, and staff attitude.

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