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OBJECTIVE: Herpes simplex virus infection through the neuronal route is the most well-studied mode of viral encephalitis that can persists in a human host for a lifetime. However, the involvement of other possible infection mechanisms by the virus remains underexplored. Therefore, this study aims to determine the temporal effects and mechanisms by which the virus breaches the human brain micro-vascular endothelial cells of the blood-brain barrier. METHOD: An electrical cell-substrate impedance-sensing tool was utilized to study the real-time cell-cell barrier or morphological changes in response to the virus infection. RESULTS: Herpes simplex virus, regardless of type (i.e., 1 or 2), reduced the cell-cell barrier resistance almost immediately after virus addition to endothelial cells, with negligible involvement of cell-matrix adhesion changes. There is no exclusivity in the infection ability of endothelial cells. From 30 h after HSV infection, there was an increase in cell membrane capacitance with a subsequent loss of cell-matrix adhesion capability, indicating a viability loss of the infected endothelial cells. CONCLUSION: This study shows for the first time that destruction of human brain micro-vascular endothelial cells as an in vitro model of the blood-brain barrier could be an alternative invasion mechanism during herpes simplex virus infection.
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Barrera Hematoencefálica/fisiología , Barrera Hematoencefálica/virología , Células Endoteliales/fisiología , Células Endoteliales/virología , Simplexvirus/crecimiento & desarrollo , Supervivencia Celular , Impedancia Eléctrica , Humanos , Modelos BiológicosRESUMEN
BACKGROUND: Burkholderia pseudomallei is the causative agent of melioidosis, which is a potentially life threatening disease endemic in Southeast Asian countries. In Malaysia, cystic fibrosis (CF) is an uncommon condition. The association between CF and B.pseudomallei infections has been reported previously. However, this is the first case report of a pediatric melioidosis relapse and co-infection with other Gram-negative bacteria in Malaysia. CASE PRESENTATION: A 14-year-old Chinese Malaysian boy presented with a history of recurrent pneumonia, poor growth and steatorrhoea since childhood, and was diagnosed with CF. B. pseudomallei was cultured from his sputum during three different admissions between 2013 and 2016. However, the patient succumbed to end stage of respiratory failure in 2017 despite antibiotics treatment against B.pseudomallei. The isolates were compared using multilocus-sequence typing and repetitive-element polymerase chain reaction (PCR), and confirmed that two of the isolates were of same sequence type, which may indicate relapse. CONCLUSIONS: CF patients should be aware of melioidosis in endemic regions, as it is an emerging infectious disease, especially when persistent or recurrent respiratory symptoms and signs of infection occur. The high prevalence rates of melioidosis in Malaysia warrants better management options to improve quality of life, and life expectancy in patients with CF. Travel activities to endemic regions should also be given more consideration, as this would be crucial to identify and initiate appropriate empiric treatment.
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Fibrosis Quística/diagnóstico , Melioidosis/diagnóstico , Adolescente , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Burkholderia pseudomallei/efectos de los fármacos , Burkholderia pseudomallei/genética , Burkholderia pseudomallei/aislamiento & purificación , Enfermedad Crónica , Fibrosis Quística/complicaciones , ADN Bacteriano/aislamiento & purificación , ADN Bacteriano/metabolismo , Humanos , Malasia , Masculino , Melioidosis/complicaciones , Melioidosis/tratamiento farmacológico , Tipificación de Secuencias Multilocus , Neumonía/complicaciones , Neumonía/diagnóstico , Recurrencia , Esputo/microbiología , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVE: To describe a prospective laboratory-based surveillance of Candida species that were collected from different anatomical sites of patients admitted to the University of Malaya Medical Centre, Malaysia, from the year 2000 to 2013. METHODS: Conventional (culture, microscopic examination and carbohydrate assimilation test) and molecular (PCR amplification and DNA sequencing) techniques were used to identify Candida species. RESULTS: A total of 16 Candida species isolated from 34 392 clinical samples were from the oral cavity (oral swabs and throat swabs), blood, respiratory tract (sputum, tracheal secretions, nasopharyngeal aspirates, bronchoalveolar lavage), high vaginal swab, pus and urine. C. albicans (66.70%, 22 941/34 392), C. glabrata (11.71%, 4029/34 392), C. parapsilopsis (10.74%, 3692/34 392), C. tropicalis (9.19%, 3162/34 392) and C. krusei (1.15%, 396/34 392) were the five predominant Candida species. C. albicans was the predominant species isolated from the oral cavity, respiratory tract and high vaginal swab; while the Candida species isolated from blood, urine and pus were predominant non-albicans Candida. Uncommon Candida species, such as C. lusitaniae, C. haemulonii, C. humicola, Pichia ohmeri and C. ciferrii, were also isolated in this study. CONCLUSION: Our study expands the current knowledge of the epidemiology of non-invasive and invasive candidiasis in Malaysia. The variability of the Candida species distribution from different anatomical sites highlights the significance of local epidemiology in disease management and selection of antifungal agents.
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This case report describes a case of presumed acute myocardial infarction in a returned traveler who was later diagnosed to have severe malaria. Emergency coronary angiography was normal and subsequent peripheral blood film was positive for Plasmodium falciparum.
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Malaria Falciparum/diagnóstico , Malaria Falciparum/patología , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/patología , Plasmodium falciparum/aislamiento & purificación , Sangre/parasitología , Angiografía Coronaria , Diagnóstico Diferencial , Humanos , Masculino , Persona de Mediana EdadRESUMEN
INTRODUCTION: Approach to managing infection in the intensive care unit (ICU) often varies between institutions and not many readily adapt to available local guidelines despite it was constructed to suite local clinical scenario. Malaysia already has two published guidelines on managing infection in the ICU but data on its compliance are largely unknown. OBJECTIVES: A cross-sectional survey was carried out and sent to a total of 868 specialists working primarily in the ICU. The aim of this study was to explore knowledge, perception, and the antibiotic prescribing practice among specialists and advanced trainees in Malaysian ICU. MATERIALS AND METHODS: A cross-sectional survey was used, consisted of three sections: knowledge, perception, and antibiotic prescribing practice in ICU. Three case vignettes on hospital-acquired pneumonia (HAP), infected necrotizing pancreatitis (INP), and catheter-related bloodstream infection (CRBSI) were used to explore antibiotic prescribing practice. RESULTS: A total of 868 eligible subjects were approached with 104 responded to the survey. Three hundred eighty-nine antibiotics were chosen from seven different classes in the case vignettes. All respondents acknowledged the importance of pharmacokinetic/pharmacodynamic (PK/PD) in antibiotic optimization and majority (97.2%) perceived that current dosing is inadequate to achieve optimal PK/PD target in ICU patients. Majority (85.6%) believed that antibiotic dose should be streamlined to the organisms' minimum inhibitory concentration (MIC). In terms of knowledge, only 64.4% provided the correct correlations between antibiotics and their respective PK/PD targets. Compliance rates in terms of antibiotic choices were at 79.8%, 77.8%, and 27.9% for HAI, INP, and CRBSI, respectively. CONCLUSION: Malaysian physicians are receptive to use PK/PD approach to optimize antibiotic dosing in ICU patients. Nonetheless, there are still gaps in the knowledge of antibiotic PK/PD as well as its application in the critically ill, especially for ß-lactams.
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INTRODUCTION: Diagnosis and management of urinary tract infection (UTI) are complex, and do not always follow guidelines. The aim of this study was to determine adherence to the 2014 Malaysian Ministry of Health guidelines for managing suspected UTI in a Malaysian primary care setting. METHODOLOGY: We retrospectively reviewed computerized medical records of adults with suspected UTI between July-December 2016. Excluded were consultations misclassified by the search engine, duplicated records of the same patient, consultations for follow-up of suspected UTI, patients who were pregnant, catheterised, or who had a renal transplant. Records were reviewed by two primary care physicians and a clinical microbiologist. RESULTS: From 852 records, 366 consultations were a fresh episode of possible UTI. Most subjects were female (78.2%) with median age of 61.5 years. The major co-morbidities were hypertension (37.1%), prostatic enlargement in males (35.5%) and impaired renal function (31.1%). Symptoms were reported in 349 (95.4%) consultations. Antibiotics were prescribed in 307 (83.9%) consultations, which was appropriate in 227/307 (73.9%), where the subject had at least one symptom, and leucocytes were raised in urine full examination and microscopic examination (UFEME). In 73 (23.8%) consultations antibiotics were prescribed inappropriately, as the subjects were asymptomatic (14,4.6%), urine was clear (17,5.5%), or UFEME did not show raised leucocytes (42,13.7%). In 7 (2.3%) consultations appropriateness of antibiotics could not be determined as UFEME was not available. CONCLUSION: Several pitfalls contributed to suboptimal adherence to guidelines for diagnosis and management of suspected UTI. This illustrates the complexity of managing suspected UTI in older subjects with multiple co-morbidities.
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Antiinfecciosos/uso terapéutico , Pruebas Diagnósticas de Rutina/métodos , Manejo de la Enfermedad , Atención Primaria de Salud/métodos , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Infecciones Relacionadas con Catéteres , Femenino , Adhesión a Directriz/estadística & datos numéricos , Humanos , Malasia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Población Urbana , Adulto JovenRESUMEN
The ST131 multilocus sequence type (MLST) of Escherichia coli is a globally successful pathogen whose dissemination is increasing rates of antibiotic resistance. Numerous global surveys have demonstrated the pervasiveness of this clone; in some regions ST131 accounts for up to 30% of all E. coli isolates. However, many regions are underrepresented in these published surveys, including Africa, South America, and Asia. We collected consecutive bloodstream E. coli isolates from three countries in Southeast Asia; ST131 was the most common MLST type. As in other studies, the C2/H30Rx clade accounted for the majority of ST131 strains. Clinical risk factors were similar to other reported studies. However, we found that nearly all of the C2 strains in this study were closely related, forming what we denote the SEA-C2 clone. The SEA-C2 clone is enriched for strains from Asia, particularly Southeast Asia and Singapore. The SEA-C2 clone accounts for all of the excess resistance and virulence of ST131 relative to non-ST131 E. coli. The SEA-C2 strains appear to be locally circulating and dominant in Southeast Asia, despite the intuition that high international connectivity and travel would enable frequent opportunities for other strains to establish themselves.
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Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple , Infecciones por Escherichia coli/epidemiología , Escherichia coli/enzimología , Virulencia/efectos de los fármacos , beta-Lactamasas/metabolismo , Asia Sudoriental/epidemiología , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/genética , Infecciones por Escherichia coli/microbiología , Genoma Bacteriano , Humanos , Tipificación de Secuencias Multilocus , Prevalencia , Factores de VirulenciaRESUMEN
Hepatitis B virus (HBV) infection is a major cause of chronic liver disease that may progress to liver cirrhosis and hepatocellular carcinoma. Host immune responses represent the key determinants of HBV clearance or persistence. Here, we investigated the role of the early activation marker, CD69 and effector cytokines, granzyme B (GrB) and IFN-γ in the exhaustion of innate-like TCR Vα7.2+CD4+T cells, in 15 individuals with chronic HBV (CHB) infection where six were HBV DNA+ and nine were HBV DNA-. The percentage of cytokine-producing T cells and MAIT cells were significantly perturbed in HBV patients relative to healthy controls (HCs). The intracellular expression of GrB and IFN-γ was significantly reduced in MAIT cells derived from HBV-infected patients as compared to HCs, and the levels correlated with the percentage and levels [mean fluorescence intensity (MFI)] of CD69 expression. The total expression of CD69 (iMFI) was lower in CHB patients as compared to HCs. The frequency of CD69+ cells correlated with the levels of cytokine expression (MFI), particularly in CHB patients as compared to HCs. In summary, the polyfunctionality of peripheral T cells was significantly reduced among CHB patients, especially in the TCR Vα7.2+CD4+T cells, and the levels of cytokine expression correlated with functional cytokine levels.
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Antígenos CD/metabolismo , Antígenos de Diferenciación de Linfocitos T/metabolismo , Linfocitos T CD4-Positivos/inmunología , Carcinoma Hepatocelular/inmunología , Virus de la Hepatitis B/fisiología , Hepatitis B Crónica/inmunología , Lectinas Tipo C/metabolismo , Neoplasias Hepáticas/inmunología , Células T Invariantes Asociadas a Mucosa/inmunología , Adulto , Células Cultivadas , Citotoxicidad Inmunológica , Femenino , Granzimas/metabolismo , Humanos , Inmunidad Innata , Interferón gamma/metabolismo , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Carga ViralRESUMEN
Chemotherapies remain far from ideal due to drug resistance; therefore, novel chemotherapeutic agents with higher effectiveness are crucial. The extracts of four Phyllanthus species, namely Phyllanthus niruri, Phyllanthus urinaria, Phyllanthus watsonii, and Phyllanthus amarus, were shown to induce apoptosis and inhibit metastasis of breast carcinoma cells (MCF-7). The main objective of this study was to determine the pathways utilized by these four Phyllanthus species to exert anti-metastatic activities. A cancer 10-pathway reporter was used to investigate the pathways affected by the four Phyllanthus species. Results indicated that these Phyllanthus species suppressed breast carcinoma metastasis and proliferation by suppressing matrix metalloprotein 2 and 9 expression via inhibition of the extracellular signal-related kinase (ERK) pathway. Additionally, inhibition of hypoxia-inducible factor 1-α in the hypoxia pathway caused reduced vascular endothelial growth factor and inducible nitric oxide synthase expression, resulting in anti-angiogenic effects and eventually anti-metastasis. Two-dimensional gel electrophoresis identified numerous proteins suppressed by these Phyllanthus species, including invasion proteins, anti-apoptotic protein, protein-synthesis proteins, angiogenic and mobility proteins, and various glycolytic enzymes. Our results indicated that ERK and hypoxia pathways are the most likely targets of the four Phyllanthus species for the inhibition of MCF-7 metastasis.
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Neoplasias de la Mama , Hipoxia de la Célula , Humanos , Sistema de Señalización de MAP Quinasas , Células MCF-7 , Phyllanthus , Extractos Vegetales , Factor A de Crecimiento Endotelial VascularRESUMEN
Cladophialophora bantiana is a dematiaceous fungus with a predilection for causing central nervous system (CNS) infection manifesting as brain abscess in both immunocompetent and immunocompromised patients. In this paper, we report comprehensive genomic analyses of C. bantiana isolated from the brain abscess of an immunocompetent man, the first reported case in Malaysia and Southeast Asia. The identity of the fungus was determined using combined morphological analysis and multilocus phylogeny. The draft genome sequence of a neurotrophic fungus, C. bantiana UM 956 was generated using Illumina sequencing technology to dissect its genetic fundamental and basic biology. The assembled 37.1 Mb genome encodes 12,155 putative coding genes, of which, 1.01% are predicted transposable elements. Its genomic features support its saprophytic lifestyle, renowned for its versatility in decomposing hemicellulose and pectin components. The C. bantiana UM 956 was also found to carry some important putative genes that engaged in pathogenicity, iron uptake and homeostasis as well as adaptation to various stresses to enable the organism to survive in hostile microenvironment. This wealth of resource will further catalyse more downstream functional studies to provide better understanding on how this fungus can be a successful and persistent pathogen in human.
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Ascomicetos/patogenicidad , Feohifomicosis Cerebral/diagnóstico , Feohifomicosis Cerebral/microbiología , Animales , Ascomicetos/clasificación , Ascomicetos/genética , Absceso Encefálico/microbiología , Infecciones Fúngicas del Sistema Nervioso Central/microbiología , Feohifomicosis Cerebral/metabolismo , Genoma Fúngico/genética , Genómica , Humanos , Masculino , Persona de Mediana Edad , Filogenia , Virulencia/genética , Virulencia/fisiologíaRESUMEN
We report the first case of an immunocompromised adult patient presenting with cervicofacial lymphadenitis due to Mycobacterium haemophilum, confirmed using hsp65 gene sequencing and line-probe assays. In resource-limited settings, especially in developing countries, appropriate culture methods and rapid molecular diagnostic tools such as hsp65 gene sequencing for identification of this organism may not be readily available. This may cause M. haemophilum infections to go unrecognised or lead to delays in diagnosis. Lack of heightened awareness about the potential for this mycobacterial species to cause infections may also contribute to possible underestimation of M. haemophilum cases in the developing world.