Browse publications by year: 2019

Fulltext Effects of annexin A1 on apoptosis and cell cycle arrest in human leukemic cell lines

Sabran A, Kumolosasi E, Jantan I

Acta Pharm, 2019 Mar 01;69(1):75-86.
PMID: 31259717 DOI: 10.2478/acph-2019-0005

Recent studies suggest that annexin A1 (ANXA1) promotes apoptosis in cancerous cells. This study aims to investigate the effects of ANXA1 on apoptosis and cell cycle arrest in K562, Jurkat and U937 cells and peripheral blood mononu-clear cells (PBMC). Cells were treated with ANXA1 and cyclophosphamide prior to flow cytometry analysis for apoptosis and cell cycle arrest induction. At 2.5µM, ANXA1 induced significant apoptosis in K562 (p ≤ 0.001) and U937 (p ≤ 0.05) cells, with EC50 values of 3.6 and 3.8 µM, respectively. In Jurkat cells, induction was not significant (EC50, 17.0 µM). No significant apoptosis induction was observed in PBMC. ANXA1 caused cycle arrest in the G0/G1 phase in K562 and U937 cells with p ≤ 0.001 for both, and (p ≤ 0.01) for Jurkat cells. ANXA1 induced apoptosis and cycle arrest in the G0/G1 phase in K562 and U937 cells, causing only cell cycle arrest in Jurkat cells.

MeSH terms: Adolescent; Adult; Cell Line; Female; Humans; Leukocytes, Mononuclear/metabolism*; Leukocytes, Mononuclear/physiology*; Male; Middle Aged; G0 Phase/physiology; G1 Phase/physiology; Apoptosis/physiology*; Annexin A1/metabolism*; Jurkat Cells; K562 Cells; U937 Cells; Cell Line, Tumor; Young Adult; Cell Cycle Checkpoints/physiology*
Fulltext Measurement of exclusive Υ photoproduction from protons in p Pb collisions at s NN = 5.02 TeV

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.

Eur Phys J C Part Fields, 2019;79(3):277.
PMID: 31007586 DOI: 10.1140/epjc/s10052-019-6774-8

The exclusive photoproduction of Υ ( nS ) meson states from protons, γ p → Υ ( nS ) p (with n = 1 , 2 , 3 ), is studied in ultraperipheral p Pb collisions at a centre-of-mass energy per nucleon pair of s NN = 5.02 TeV . The measurement is performed using the Υ ( nS ) → μ + μ - decay mode, with data collected by the CMS experiment corresponding to an integrated luminosity of 32.6 nb - 1 . Differential cross sections as functions of the Υ ( nS ) transverse momentum squared p T 2 , and rapidity y, are presented. The Υ ( 1 S ) photoproduction cross section is extracted in the rapidity range | y | < 2.2 , which corresponds to photon-proton centre-of-mass energies in the range 91 < W γ p < 826 GeV . The data are compared to theoretical predictions based on perturbative quantum chromodynamics and to previous measurements.
Fulltext Measurement of the t t ¯ production cross section, the top quark mass, and the strong coupling constant using dilepton events in pp collisions at s = 13 Te

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.

Eur Phys J C Part Fields, 2019;79(5):368.
PMID: 31148943 DOI: 10.1140/epjc/s10052-019-6863-8

A measurement of the top quark-antiquark pair production cross section σ t t ¯ in proton-proton collisions at a centre-of-mass energy of 13 Te is presented. The data correspond to an integrated luminosity of 35.9 fb - 1 , recorded by the CMS experiment at the CERN LHC in 2016. Dilepton events ( e ± μ ∓ , μ + μ - , e + e - ) are selected and the cross section is measured from a likelihood fit. For a top quark mass parameter in the simulation of m t MC = 172.5 Ge the fit yields a measured cross section σ t t ¯ = 803 ± 2 (stat) ± 25 (syst) ± 20 (lumi) pb , in agreement with the expectation from the standard model calculation at next-to-next-to-leading order. A simultaneous fit of the cross section and the top quark mass parameter in the powheg simulation is performed. The measured value of m t MC = 172.33 ± 0.14 (stat) - 0.72 + 0.66 (syst) Ge is in good agreement with previous measurements. The resulting cross section is used, together with the theoretical prediction, to determine the top quark mass and to extract a value of the strong coupling constant with different sets of parton distribution functions.
Fulltext Measurement of exclusive ρ 770 0 photoproduction in ultraperipheral pPb collisions at s NN = 5.02 Te

Sirunyan AM, Tumasyan A, Adam W, Ambrogi F, Asilar E, Bergauer T, et al.

Eur Phys J C Part Fields, 2019;79(8):702.
PMID: 31524889 DOI: 10.1140/epjc/s10052-019-7202-9

Exclusive ρ 770 0 photoproduction is measured for the first time in ultraperipheral pPb collisions at s NN = 5.02 Te with the CMS detector. The cross section σ ( γ p → ρ 770 0 p ) is 11.0 ± 1.4 (stat) ± 1.0 (syst) μ b at ⟨ W γ p ⟩ = 92.6 Ge for photon-proton centre-of-mass energies W γ p between 29 and 213 Ge . The differential cross section d σ / d | t | is measured in the interval 0.025 < | t | < 1 Ge 2 as a function of W γ p , where t is the squared four-momentum transfer at the proton vertex. The results are compared with previous measurements and theoretical predictions. The measured cross section σ ( γ p → ρ 770 0 p ) has a power-law dependence on the photon-proton centre-of-mass, consistent with electron-proton collision measurements performed at HERA. The W γ p dependence of the exponential slope of the differential cross section d σ / d | t | is also measured.
Fulltext Factors Associated With an Interest in Practice-Based Research Among Pharmacists in Nigeria

Shitu Z, Jatau AI, Mustapha M, Gulma KA, Ado B, Sha'aban A

J Pharm Technol, 2019 Jun;35(3):98-104.
PMID: 34861029 DOI: 10.1177/8755122519831384

Background: Practice-based research (PBR) is employed in the pharmacy profession to improve the quality and efficiency of health care delivery. Although widely practiced in developed countries, it is rarely used in developing countries, including Nigeria. Objectives: To determine the factors associated with Nigerian pharmacists' interest in PBR. Methods: This is a cross-sectional study utilizing an online survey. Pharmacists currently practicing in Nigeria were invited to participate. A hyperlink to the online questionnaire was shared with members of relevant professional bodies via Facebook, WhatsApp, and Twitter. Reminders were sent to facilitate a high response rate. Factors associated with pharmacists' interest in PBR were determined using multiple logistic regression. Results: Two hundred and three completed responses were received from the survey. The majority, 94.6% (192), expressed an interest in PBR and believed that it would enhance their pharmacy practice and role in patient care. The multivariable analysis showed that pharmacists' interest in publishing their research findings in peer-reviewed journals (odds ratio = 0.004, 95% confidence interval = 0.00-0.05, P < .001) and their knowledge of the professional relevance of research pertaining to their area of practice within the health care system (odds ratio = 0.02, 95% confidence interval = 0.00-0.47, P = .015) were found to be independent predictors of pharmacists' interest in PBR. Conclusion: There is an interest in PBR among practicing pharmacists in Nigeria. The provision of evidence-based pharmaceutical services in Nigeria will be enhanced by interventions that encourage the conduct of research and publication of research findings, and by improving knowledge of the professional relevance of PBR in pharmacy practice areas.
Fulltext Validation of self-reported smoker and second hand smoke exposure by urinary cotinine within The Malaysian Cohort Project

Abdullah N, Al-Junid SH, Looi ML, Chin SF, Mohd Haniff EA, Syed Zakaria SZ, et al.

Journal of Biomedicine and Translational Research, 2019;5(1):15-22.

Background: Validation of self-reported questionnaire is very crucial in ensuring the quality and reliability of data collection.
Objective: The aim of this study were i) to validate the questionnaire on tobacco smoke intake and second hand smoke exposure among The Malaysian Cohort (TMC) subjects through the determination of urinary cotinine levels, ii) to determine the optimal cut-off point of urine cotinine that discriminates smokers from non-smokers and iii) to estimate misclassification rate between self-reported smoking and urinary cotinine level.
Methods: Urine samples from a total of 775 The Malaysian Cohort subjects (104 smokers, 102 former smokers and 569 non-smokers) were obtained and urinary cotinine levels were determined by high-performance liquid chromatography (HPLC). Differences between groups were compared using Kruskal Wallis and Mann-Whitney tests. The Receiver Operating Characteristic (ROC) curved was performed to define the optimal urinary cotinine cut-off point.
Results: Urinary cotinine concentration significantly (p<0.001) correlated with smoking status (r=0.46), the average number of cigarettes smoked per day (r=0.53), duration of smoking (r=0.33) and number of cigarettes packed per year (r=0.47). Smokers and second hand smokers have significantly higher median cotinine levels (978.40 and 21.31 respectively) compared to non-smokers (15.52) and non-exposed (13.60) subjects. Cotinine level at cut-off value of 1.51 ng/mg creatinine is able to distinguish smokers and non-smokers with a sensitivity of 84.62% and specificity of 81.97%.
Conclusion: The Malaysian Cohort self-reported smoking questionnaire is a reliable tool in assessing the use of tobacco and second hand smoke exposure among the subjects.
Study name: The Malaysian Cohort (TMC) project

MeSH terms: Adult; Cotinine; Cross-Sectional Studies; Humans; Malaysia; Sensitivity and Specificity; Smoking; Tobacco Smoke Pollution; Self Report
Risk factors associated with flea infestation on cats

Azrizal-Wahid N, Sofian-Azirun M, Low VL

Trop Biomed, 2019 Dec 01;36(4):810-821.
PMID: 33597453

Fleas are the common cause of skin disorders in cats. They are well-known for transmitting various pathogens to both cats and humans. Accordingly, this study was conducted to gain insights on the risk factors associated with flea infestation on cats. Flea combing conducted on 426 cats from four distinct regions in Peninsular Malaysia revealed a relatively high rate of flea infestation on 306 cats (71.83%). A total of 651 fleas were collected, all of them were identified as Ctenocephalides felis with the total intensity of 2.13 and abundance of 1.53. The sex ratio of fleas was female-biased at 2.5:1 (♀=464, ♂=187). Statistical analysis of the data revealed that flea infestation was significantly (P<0.05) associated with several risk factors including region, age, weight, status (stray, sheltered, pet), body condition, and hair length. Higher flea prevalence was also observed in female cats (77.99%), big-sized cats (91.76%), stray cats (84.94%), cats with clean body condition (73.35%), and cats with long hairs (78.38%) as compared to their contemporaries within the same comparison variables. The high infestation of fleas in this study is indicative of cats as a flea reservoir particularly C. felis. Thus the findings of this study and the knowledge gained on the risk factors can be used to develop and improve control measures and management of flea infestations.

MeSH terms: Animals; Cat Diseases/parasitology*; Cats/parasitology*; Cross-Sectional Studies; Female; Malaysia; Male; Risk Factors; Sex Ratio; Ctenocephalides; Flea Infestations/veterinary*
An ensemble model for forecasting infectious diseases in India

Shashvat K, Basu R, Bhondekar PA, Kaur A

Trop Biomed, 2019 Dec 01;36(4):822-832.
PMID: 33597454

Time series modelling and forecasting plays an important role in various domains. The objective of this paper is to construct a simple average ensemble method to forecast the number of cases for infectious diseases like dengue and typhoid and compare it by applying models for forecasting. In this paper we have also evaluated the correlation between the number of typhoid and dengue cases with the ecological variables. The monthly data of dengue and typhoid cases from 2014 to 2017 were taken from integrated diseases surveillance programme, Government of India. This data was analysed by three models namely support vector regression, neural network and linear regression. The proposed simple average ensemble model was constructed by ensemble of three applied regression models i.e. SVR, NN and LR. We combine the regression models based upon the error metrics such as Mean Square Error, Root Mean Square Error and Mean Absolute Error. It was found that proposed ensemble method performed better in terms of forecast measures. The finding demonstrates that the proposed model outperforms as compared to already available applied models on the basis of forecast accuracy.

MeSH terms: Communicable Diseases/epidemiology*; Dengue/epidemiology; Forecasting; Humans; India/epidemiology; Typhoid Fever/epidemiology; Models, Statistical; Linear Models; Neural Networks (Computer); Support Vector Machine
Multidisciplinary biomarkers aggrieve morbidity in schistosomiasis

Noha MA, Enas AE, Aly E, Mohamed AE

Trop Biomed, 2019 Dec 01;36(4):833-844.
PMID: 33597455

BACKGROUND: Biomarkers by definition are measurable molecules that mark the evidence of certain pathological processes. Collaboration of various biomarkers influences morbidity of schsitosomiasis in Egypt.
OBJECTIVES: To identify the biomarkers: CRP, IgE, hemoglobin, ferritin, vitamin D, and platelets in terms of relationship with active and chronic schistosomiasis; demographic data, and their interinfluence.
STUDY DESIGN: A cross-sectional study.
METHODS: Parasitological analysis of stool and urine samples, Indirect Hemagglutination Test, Enzyme linked Immunoassay, Hematology Analyzer, and Statistical Package SPSS (Statistical Package for the Social Sciences) version 25.
RESULTS: Out of 400 participants, 25% suffered of schistosomiasis: active S. mansoni infections in 7 cases (1.75%), S. haematobium infections in 6 cases (1.5%), and chronic schistosomiasis infections in 20 cases (5%). Creactive protein (CRP) likewise IgE levels were higher in active S. mansoni and S. haematobium infections when compared with chronic schistosomiasis. IgE levels appeared to affect infection intensity in S. haematobium. Inversely, hemoglobin (Hb) values were low in active schistosomiasis and upgraded in chronic infection (*p<0.05). Ferritin levels varied in active Schistosoma infection and normalized during chronicity. Vitamin D was reduced in active and chronic schistosomiais. Platelet counts were within normal ranges throughout the study groups. Distribution of ferritin, vit D, and platelets was statistically insignificant among Schistosoma infected population. Age affected only hemoglobin, CRP, and IgE biomarkers. CRP and IgE were in direct relationship together and inversely proportional with hemoglobin (*P <0.05).
CONCLUSION: Anemia increased proportionally with biomarkers of inflammatory stress (CRP and IgE) in early infections. Meanwhile, Hb and ferritin (iron stores) improved during chronicity. Hypovitaminosis-D associated the entire course of schistosomiasis while platelet counts were not affected.

MeSH terms: Age Factors; Anemia/parasitology; Cross-Sectional Studies; Egypt/epidemiology; Humans; Morbidity; Schistosomiasis haematobia/epidemiology*; Schistosomiasis mansoni/epidemiology*; Biomarkers/blood
Sudden death due to infective endocarditis caused by Streptococcus constellatus: A case report

Zamasry MS, Hilmi Z, Mohd Yusof MYP, Razali HSA, Nawawi H, Mahmood MS

Trop Biomed, 2019 Dec 01;36(4):845-849.
PMID: 33597456

Infective endocarditis (IE) is a relatively uncommon disease, but has been challenging to diagnose over the years. With the increasing incidence, variety of causative agents and the resistance of microorganisms towards antibiotics, there is still an occurrence of sudden death due to undiagnosed IE. The most common microorganism causing IE is Staphylococcus aureus. However, there is increasing prevalence of other microorganisms causing IE. This case report highlights a case of sudden death due to IE caused by a rare pathogen, Streptococcus constellatus which belongs to the Streptococcus anginosus group (Milleri group). A study noted the crude incidence of IE in 6 world regions ranged between 1.5 and 11.6 cases per 100,000 people. To date, there has been no previous report on sudden death due to IE caused by Streptococcus constellatus in Malaysia, neither in the forensic nor clinical setting. This case report underlined the characteristics and pathological features of this microorganism. The increasing incidence and variety of causative organisms in IE are important public health issues. It is vital for future studies to examine the risk factors of IE related to Streptococcus constellatus, to enhance better understanding, insight and awareness regarding the course of this disease. This in turn may facilitate preventive measures to avoid morbidity and mortality from this condition.

MeSH terms: Adult; Endocarditis, Bacterial/diagnosis*; Endocarditis, Bacterial/microbiology; Humans; Male; Streptococcal Infections/diagnosis*; Fatal Outcome; Streptococcus constellatus*
Post mortem computed tomography (PMCT) guided lung biopsy: A preliminary case report

Abdul Hadi D, Mansharan Kaur CS, Effat O, Siew SF

Trop Biomed, 2019 Dec 01;36(4):850-854.
PMID: 33597457

Tuberculosis (TB) is a highly infectious disease on the rise caused by the organism Mycobacterium tuberculosis and health care workers working in emergency departments, medical wards and autopsy rooms are in danger of contacting this disease. We present a case of a 42 year old man found dead under a pedestrian bridge with no medical history available. Post mortem computed tomography showed multiple cavities involving upper lobes of both lungs and areas of consolidation in both lung fields raising the suspicion of pulmonary tuberculosis. This was followed by a computed tomography guided lung biopsy and a limited conventional autopsy done in situ in a special high risk autopsy suite with appropriate ventilation. This case highlights the importance of cross sectional imaging which can be coupled with image guided biopsy in cases of infectious disease to reduce the risk of transmission to health care workers.

MeSH terms: Adult; Biopsy; Humans; Lung; Lung Diseases/diagnosis*; Lung Diseases/pathology; Malaysia; Male; Tomography, X-Ray Computed*; Tuberculosis/diagnosis*; Tuberculosis/pathology; Forensic Pathology
A preliminary proteomic study of permethrin resistant and susceptible Aedes aegypti (L.)

Rosilawati R, Nabila R, Siti Futri Farahininajua F, Nazni WA, Lee HL

Trop Biomed, 2019 Dec 01;36(4):855-865.
PMID: 33597458

The mechanism of insecticide resistance is traditionally attributed to detoxification enzymes, target site alteration, decreased penetration of insecticides and behavioural resistance. Other form of mechanisms, such as the role of protein(s) in resistance is unknown. In the present study, the protein profiling of both IMR-PSS strain (permethrin-selected) and IMR-LS strain (laboratory-susceptible) 24 hours post exposure period to permethrin was carried out via 1D-gel electrophoresis and liquid chromatography mass spectrometry (LC-MS/ MS). The bands which appeared in the gel of 1D-electrophoresis revealed an abundance of proteins. The band pattern of both strains looked macroscopically alike and differed only in band intensity. However, LC-MS/MS analysis revealed that the IMR-PSS strain produced extra 388 peptides that were not found in the IMR-LS strain, indicating that IMR-PSS strain reacted differently from IMR-LS strain as a result of persistent exposure to permethrin. Since the complex banding patterns of 1D-gel electrophoresis were difficult to interpret the significance of the protein difference between IMR-PSS and IMR-LS strain, hence LC-MS/MS analysis is ideally suited for better protein resolution and thus will allow more in-depth comparison of the complex pattern. The findings here provide the first preliminary evidence that insecticide resistance in mosquito induces up regulation of proteins that may be protective to mosquitoes against insecticide and proteins could be another mechanism that contributes to development of resistance.

MeSH terms: Aedes/genetics*; Animals; Insecticide Resistance/genetics*; Insecticides; Insect Proteins/genetics; Permethrin*; Proteomics*
Identification and characterization of Leishmania amastigote and axenic form antigens

Abdelhaleem AA, Elamin EM, Bakheit SM, Mukhtar MM

Trop Biomed, 2019 Dec 01;36(4):866-873.
PMID: 33597459

This study was aimed to identify and characterize Leishmania amastigote, and axenic form antigens. Two in vitro techniques were used to change leishmania parasite isolates from promastigote form to amastigotes and amastigote like (axenic) forms. The main strategy relied upon in vitro infection of murine macrophages cell line J774 with leishmania promastigote, at 37°C with 5% CO2, while the second technique relied upon the culture of promastigote at 37°C with low pH (5.5), and 5-10% CO2. Proteins were extracted and fractionated utilizing 12% Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS PAGE). Antigens were recognized using both immune dot blot and western blot procedures. PCR was performed for recognition of leishmania parasites in infected J774 macrophages. L. major was quicker in infectivity of macrophages cell line than L. donovani. Shared proteins ranging from 26-116 kDa were identified by SDS PAGE in all stages. Immune Dot-blot method showed positive outcomes, while western blot identified an exceptional antigen band of 16 kDa in amastigote, this unique band could be of value in diagnosis and vaccination of leishmaniasis. PCR results confirmed presence of both isolates demonstrating that coinfection is conceivable, and no indications of hereditary recombination at kinetoplast DNA (kDNA) were identified in macrophages simultaneously infected by L. major and L. donovani.

MeSH terms: Animals; Antigens, Protozoan/analysis*; Cell Line; Electrophoresis, Polyacrylamide Gel; Leishmania/immunology; Leishmania/isolation & purification*; Leishmania donovani; Macrophages/parasitology*; Blotting, Western; Leishmania major; Mice
Analysis of IL-4 promoter and VNTR polymorphisms in Thai patients with pulmonary tuberculosis

Kulpraneet M, Limtrakul A, Thanomtham P, Taemaitree N, Puttikamonkul S, Pongsunk S, et al.

Trop Biomed, 2019 Dec 01;36(4):874-882.
PMID: 33597460

Tuberculosis (TB) is a leading cause of morbidity and mortality in Thailand. Cytokines play important roles in defense against Mycobacterium tuberculosis infection. Interleukin (IL)-4 is one of the anti-inflammatory cytokines and has been found to be elevated in TB patients. The common polymorphisms in IL-4 gene, including IL-4-590C/T, IL-4-33C/T, and IL-4-variable number of tandem repeats (VNTR) intron 3 have been reported to be associated with risk for some diseases. The purpose of this study was to investigate possible associations between the above mentioned three common functional polymorphisms in the IL-4 gene in patients with pulmonary tuberculosis (PTB) in a Thai population. Forty three patients with PTB and 90 healthy control subjects were studied. The three common polymorphisms of the IL-4 gene were determined using polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (PCR-RFLP). The allele and genotype frequencies of IL-4 -590 C/T, -33 C/T, VNTR intron 3 polymorphisms did not show significant differences between PTB patients and healthy controls (genotype: p=0.88, p=0.92, p=0.40; allele: p=0.38, p=0.44, p=0.53, respectively). However, the allele distribution of the IL-4 -590 C, -33 C, and VNTR R3 was higher among PTB patients (25.58%, 25.58%, 25.58%, respectively) than among control subjects (20%, 20.48%, 19.44%, respectively). This may suggest that IL-4-590C/T, -33C/T and VNTR intron 3 might play a role in susceptibility to PTB. A larger cohort may possibly help conclude our findings.

MeSH terms: Genotype; Humans; Introns; Promoter Regions, Genetic*; Polymorphism, Restriction Fragment Length; Thailand; Tuberculosis, Pulmonary/genetics*; Interleukin-4/genetics*; Case-Control Studies; Polymerase Chain Reaction; Minisatellite Repeats*; Genetic Predisposition to Disease
Cellulitis due to Shewanella algae: Crucial diagnostic clues from basic microbiological tests

Ding CH, Wahab AA, Muttaqillah NAS, Kamarudin N, Saarah WR

Trop Biomed, 2019 Dec 01;36(4):883-887.
PMID: 33597461

Shewanella spp. are infrequently implicated in human infections but they are emerging pathogens with particular significance in regions with warm climates, such as Southeast Asia. This is a case of a middle-aged diabetic and hypertensive man who presented with worsening congestive heart failure symptoms associated with fever and a painful right leg. His right leg had numerous scabs and was tender, warm and erythematous. He was provisionally diagnosed with decompensated heart failure precipitated by cellulitis and uncontrolled hypertension. His blood grew non-fermentative, oxidase-positive and motile gram-negative bacilli which produced hydrogen sulfide on triple sugar iron agar. When cultured on blood agar, mucoid and weakly β-haemolytic colonies were observed after 48 hours. API 20 NE named the isolate as Shewanella putrefaciens but 16S rRNA sequence analysis identified the organism as Shewanella algae. The patient was treated with a 10-day course of ceftazidime, which resulted in the resolution of the cellulitis.

MeSH terms: Ceftazidime/therapeutic use; Cellulitis/diagnosis; Cellulitis/microbiology*; Heart Failure; Humans; Male; Middle Aged; RNA, Ribosomal, 16S/genetics; Gram-Negative Bacterial Infections/diagnosis*; Shewanella*
Zika virus modulates blood-brain barrier of brain microvascular endothelial cells

Ismail AA, Mahboob T, Samudi Raju C, Sekaran SD

Trop Biomed, 2019 Dec 01;36(4):888-897.
PMID: 33597462

Zika virus (ZIKV) is a mosquito-borne Flaviviruses. ZIKV is known to cause birth defect in pregnant women, especially microcephaly in the fetus. Hence, more study is required to understand the infection of Zika virus towards human brain microvascular endothelial cells (MECs). In this study, brain MECs were infected with ZIKV at MOI of 1 and 5 in vitro. The changes in barrier function and membrane permeability of ZIKV-infected brain MECs were determined using electric cell-substrate impedance sensing (ECIS) system followed by gene expression of ZIKV-infected brain MECs at 24 hours post infection using one-color gene expression microarray. The ECIS results demonstrated that ZIKV infection enhances vascular leakage by increasing cell membrane permeability via alteration of brain MECs barrier function. This was further supported by high expression of proinflammatory cytokine genes (lnc-IL6-2, TNFAIP1 and TNFAIP6), adhesion molecules (CERCAM and ESAM) and growth factor (FIGF). Overall, findings of this study revealed that ZIKV infection could alter the barrier function of brain MECs by altering adhesion molecules and inflammatory response.

MeSH terms: Zika Virus Infection/pathology*; Zika Virus Infection/virology; Zika Virus; Blood-Brain Barrier/virology*; Brain/blood supply; Brain/virology; Cells, Cultured; Humans; Endothelial Cells/virology*
Global status of Toxoplasma gondii infection: systematic review and prevalence snapshots

Molan A, Nosaka K, Hunter M, Wang W

Trop Biomed, 2019 Dec 01;36(4):898-925.
PMID: 33597463

Our group sought to determine the global status of T. gondii infection and to evaluate any continental and geographical trends by systematically examining the currently available epidemiological data on the prevalence of T. gondii infection. A comprehensive literature search was conducted from 10 electronic databases (Google Scholar, Science Direct, Embase, PubMed, PLOS ONE, Web of Knowledge, SciELO, MyAIS, Free Medical Journals, and Scopus) without date or language restrictions. Specific medical subject heading terms were used to search for human T. gondii seroprevalence studies that recruited subjects from general apparently healthy populations. The data were collated and analysed for both continental and global trends. The search identified 152 published studies that examined a total of 648,010 subjects. From these, 166,255 were seropositive for T. gondii infection indicating an average global seroprevalence rate of 25.7% (95% CI: 25.6 - 25.8%). The overall range of seroprevalence was determined to be 0.5 - 87.7%. African countries had the highest average seroprevalence rate of 61.4%, followed by Oceania with 38.5%, South America with 31.2%, Europe with 29.6%, USA/Canada with 17.5%, and Asia with 16.4%. Numerous environmental and human factors affect the differences in T. gondii seroprevalence rates observed between the various countries and continents. Monitoring the source and transmission may assist public health authorities to clarify the risk factors involved, as well as focus on implementing optimal state-specific health policies targeting T. gondii transmission control.

MeSH terms: Humans; Toxoplasma; Toxoplasmosis/epidemiology*; Global Health; Prevalence; Seroepidemiologic Studies
A method for distinguishing the important malaria vectors Anopheles dirus and An. cracens (Diptera: Culicidae) based on antennal sensilla of adult females

Taai K, Harbach RE, Somboon P, Sriwichai P, Aupalee K, Srisuka W, et al.

Trop Biomed, 2019 Dec 01;36(4):926-937.
PMID: 33597464

Some species of the Anopheles dirus species complex are considered to be highly competent malaria vectors in Southeast Asia. Anopheles dirus is the primary vector of Plasmodium falciparum and P. vivax while An. cracens is the main vector of P. knowlesi. However, these two species are difficult to distinguish and identify based on morphological characters. Hence, the aim of this study was to investigate the potential use of antennal sensilla to distinguish them. Large sensilla coeloconica borne on the antennae of adult females were counted under a compound light microscope and the different types of antennal sensilla were examined in a scanning electron microscope. The antennae of both species bear five types of sensilla: ampullacea, basiconica, chaetica, coeloconica and trichodea. Observations revealed that the mean numbers of large sensilla coeloconica on antennal flagellomeres 2, 3, 7, 10 and 12 on both antennae of both species were significantly different. This study is the first to describe the types of antennal sensilla and to discover the usefulness of the large coeloconic sensilla for distinguishing the two species. The discovery provides a simple, reliable and inexpensive method for distinguishing them.

MeSH terms: Animals; Anopheles/anatomy & histology*; Anopheles/classification; Female; Microscopy, Electron, Scanning; Sensilla/anatomy & histology*; Sensilla/ultrastructure; Mosquito Vectors/anatomy & histology*; Mosquito Vectors/classification
Genetic diversity and DNA barcoding of the black fly (Diptera: Simuliidae) vectors of parasites causing human onchocerciasis in Guatemala

Pramual P, Bunchom N, Saijuntha W, Tada I, Suganuma N, Agatsuma T

Trop Biomed, 2019 Dec 01;36(4):938-957.
PMID: 33597465

Genetic variation based on mitochondrial cytochrome c oxidase I (COI) and II (COII) sequences was investigated for three black fly nominal species, Simulium metallicum Bellardi complex, S. callidum Dyar and Shannon, and S. ochraceum Walker complex, which are vectors of human onchocerciasis from Guatemala. High levels of genetic diversity were found in S. metallicum complex and S. ochraceum complex with maximum intraspecific genetic divergences of 11.39% and 4.25%, respectively. Levels of genetic diversity of these nominal species are consistent with species status for both of them as they are cytologically complexes of species. Phylogenetic analyses revealed that the S. metallicum complex from Guatemala divided into three distinct clades, two with members of this species from several Central and South American countries and another exclusively from Mexico. The Simulium ochraceum complex from Guatemala formed a clade with members of this species from Mexico and Costa Rica while those from Ecuador and Colombia formed another distinct clade. Very low diversity in S. callidum was found for both genes with maximum intraspecific genetic divergence of 0.68% for COI and 0.88% for COII. Low genetic diversity in S. callidum might be a consequence of the result being informative of only recent population history of the species.

MeSH terms: Animals; Guatemala; Insect Vectors/genetics; Insect Vectors/parasitology; Onchocerciasis/transmission; Phylogeny*; Simuliidae/genetics*; Simuliidae/parasitology; Genetic Variation*; DNA Barcoding, Taxonomic
In vitro adhesion and invasion by Cladosporium sphaerospermum in human bronchial epithelial cells (BEAS-2B) and human pulmonary alveolar epithelial cells (HPAEpiC)

Lo SG, Wong SF, Mak JW, Choo KK, Ng KP

Trop Biomed, 2019 Dec 01;36(4):958-971.
PMID: 33597466

Cladosporium spores are ubiquitous in indoor and outdoor environment and may potentially trigger allergic responses upon inhalation. To date, there is limited investigation on the fate of Cladosporium spores after being inhaled into the respiratory tract. This study was conducted to investigate the interaction of Cladosporium sphaerospermum with Human Bronchial Epithelial Cells (BEAS-2B) and Human Pulmonary Alveolar Epithelial Cells (HPAEpiC). C. sphaerospermum conidia were harvested and co-cultured with BEAS-2B or HPAEpiC cells for 72 hours. At each time point (30 minutes, 2, 4, 24, 48 and 72 hours), adherence and invasion of the cells by C. sphaerospermum conidia (and hyphae) were investigated by immunofluorescence staining. This study demonstrated the adherence and internalization of C. sphaerospermum conidia within these epithelial cells. In addition, the conidia were able to germinate and invade the epithelial cells. The ability of the fungal conidia to adhere, internalize, germinate and invade both the bronchial and alveolar epithelial cells of the respiratory tract in vitro might contribute to the understanding of the pathogenesis of Cladosporium in respiratory infection and allergy in vivo.

MeSH terms: Bronchi/cytology; Cell Line; Cladosporium/pathogenicity*; Epithelial Cells/microbiology*; Humans; Spores, Fungal; Pneumocytes/microbiology*

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