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1.
Malays J Pathol ; 45(2): 195-204, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37658529

RESUMEN

INTRODUCTION: Extracellular vesicles (exosome-like vesicles) are small membrane vesicles ranging from 20-200nm in size that are released by various cells into the extracellular space. These extracellular vesicles play a major role in cell-to-cell communication and contain materials, such as proteins, mRNAs, microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). The effect of exosomes derived from an invasive colon cancer cell line on angiogenesis is unclear. Hence, the aim of this study is to investigate the effect of exosomes derived from an invasive colon cancer cell line on angiogenesis of endothelial cells. MATERIALS AND METHODS: In the present study, the exosomes from the cell culture supernatants of an invasive colon cancer cell line SW480-7 were characterised. The effect on tube formation and expression of angiogenic genes in a microvascular endothelial cell, telomerase-immortalised microvascular endothelial cell (TIME) was examined after co-cultured with exosomes secreted from SW480-7. RESULTS: Zetasizer result showed average diameter of exosomes derived from SW480-7 was 246.2 nm and morphological analysis showed the size of majority of exosomes were less than 200 nm. Results showed that exosomes derived from SW480-7 increased tube formation and up-regulated FGFR3 mRNA expression in TIME. CONCLUSION: Our findings suggest that exosomes derived from SW480-7 increased tube formation and up-regulated expression of FGFR3 mRNA in TIME.

2.
Clin Oncol (R Coll Radiol) ; 35(2): e182-e188, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36535850

RESUMEN

AIMS: To assess the risk of cardiac toxicity following radical radiotherapy in advanced lung cancer patients. MATERIALS AND METHODS: Patients with a diagnosis of stage III non-small cell lung cancer (NSCLC) receiving chemoradiotherapy were extracted from a population-based cohort in Ontario, Canada. The primary outcome of cardiac toxicity, defined as cardiac events or congestive heart failure, was assessed at 1 and 5 years following chemoradiotherapy. Secondary outcomes included overall survival, survival in relationship to post-treatment cardiac events and the effect of radiotherapy technique on cardiac toxicity. RESULTS: In total, 2031 NSCLC patients were included. The cumulative incidence of cardiac toxicity at 5 years was 20.3% (18.4-22.3). The median survival was 13.7 months in NSCLC patients who had a cardiac event post-chemoradiotherapy compared with 23.4 months in those who did not (P = 0.012). There was a trend towards increased cumulative cardiac toxicity (hazard ratio 3.37, P = 0.14) with three-dimensional conformal radiotherapy compared with intensity-modulated or volumetric arc radiotherapy techniques. CONCLUSION: The risk of cardiac events and congestive heart failure 5 years after radical thoracic radiotherapy appears high and survival is inferior at 1 year in those patients who experience a cardiac event post-treatment. More conformal radiotherapy techniques may help reduce cardiac toxicity. Further studies should investigate adaptive treatment planning and close monitoring and intervention in this high-risk group after chemoradiotherapy.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Insuficiencia Cardíaca , Neoplasias Pulmonares , Radioterapia de Intensidad Modulada , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/radioterapia , Estudios de Cohortes , Cardiotoxicidad/etiología , Radioterapia de Intensidad Modulada/métodos , Quimioradioterapia/efectos adversos , Quimioradioterapia/métodos , Morbilidad , Insuficiencia Cardíaca/etiología , Ontario/epidemiología , Estudios Retrospectivos , Estadificación de Neoplasias
3.
Malays J Pathol ; 44(2): 187-201, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36043582

RESUMEN

BACKGROUND: Worldwide, diabetic kidney disease (DKD) remains the leading cause of chronic kidney disease (CKD) and its successor, the end stage renal disease, both of which constitute major morbidity and mortality concerns. CONTENT: The residual risk of disease progression remains despite the advert of newer therapeutic modalities and current biomarkers. Meanwhile, microRNAs (miRNAs) are small non-coding RNAs, which regulate gene expression post-translationally by binding to specific mRNAs. Circulating miRNAs are increasingly recognised as novel biomarker or therapeutic targets, owing to their unique characteristics, such as their resilience to degradation by endogenous RNases, multiple downstream targets, involvement in biological processes, some degree of tissue specificity, relatively easy access and quantification. Unlike proteins, there are far less miRNAs and mature miRNAs are highly stable, structurally less complex without post-translational modification with high degree of conservation across species. Aberrant expression of miRNAs has been established in both in vitro and in vivo models of DKD. An up-to-date compilation of previous studies involving selected circulating miRNAs in blood and urine samples of DKD patients is discussed herein. SUMMARY: This review highlights the unmet clinical challenges and dysregulation of miRNAs in the pathogenesis of DKD.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , MicroARNs , Insuficiencia Renal Crónica , Biomarcadores , Nefropatías Diabéticas/genética , Nefropatías Diabéticas/metabolismo , Progresión de la Enfermedad , Humanos , MicroARNs/genética , MicroARNs/metabolismo
4.
Malays J Pathol ; 44(1): 67-74, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35484888

RESUMEN

INTRODUCTION: Colorectal cancer (CRC) is the third most common cancer worldwide and the second leading cancer in Malaysia. Despite advanced therapies, many cases of recurrence and resistance have been reported. Aberrant DNA methylation of HER3 has been implicated in carcinogenesis of CRC mainly through the regulation of gene expression. Hence, the objective of this study was to determine the status of HER3 DNA methylation and its effects on gene expression in CRC. MATERIALS AND METHODS: Fifty-nine of archival formalin-fixed, paraffin-embedded CRC cases with the adjacent normal colon tissues were retrieved. Manual micro-dissection was performed prior to RNA and DNA extraction. HER3 gene expression and DNA methylation status was evaluated by qPCR and methylation-specific PCR (MSP) techniques respectively. RESULTS: Upregulation of HER3 mRNA was found in CRC tissue compared to its adjacent normal colon tissue (8.04-fold). Of 59 CRC samples, 8.5% were methylated and 91.5% were unmethylated (hypomethylation). In the adjacent normal colon tissues, methylated and unmethylated tissue were observed in 6.8%and 93.2% respectively. DNA methylation of HER3 showed a significant association with tumour differentiation and tumour location. CONCLUSION: This study showed upregulation and hypomethylation of the HER3 gene in CRC cases. Epigenetic alterations were also found in the adjacent normal colon tissues. Thus, upregulation and hypomethylation of HER3 may play a key role in carcinogenesis of CRC. Hypomethylation of CpG islands might be associated with early steps during carcinogenesis. The findings of this biomarker serve a powerful approach to improve the current diagnostic and therapeutic measures.


Asunto(s)
Adenocarcinoma , Neoplasias Colorrectales , Adenocarcinoma/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinogénesis , Neoplasias Colorrectales/patología , Metilación de ADN , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Humanos
5.
Curr Oncol ; 27(1): e1-e8, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32218662

RESUMEN

Background: Pancreatic cancer (pcc) is one of the most lethal types of cancer, and surgery remains the optimal treatment modality for patients with resectable tumours. The objective of the present study was to examine and compare trends in the survival rate based on treatment modality in patients with pcc. Methods: This population-based retrospective analysis included all patients with known-stage pcc in Ontario between 2007 and 2015. Flexible parametric models were used to conduct the survival analysis. Survival rates were calculated based on treatment modality, while adjusting for patient- and tumour-specific covariates. Results: The study included 6437 patients. We found no noticeable improvement in survival for patients with stage iii or iv tumours; however, for stage i disease, the 1-, 2-, and 5-year survival rates increased over time to 81% from 51%, to 71% from 35%, and to 61% from 22% respectively. Most improvements were seen for surgical modalities, with 2-year survivals increasing to 89% from 65% for distal pancreatectomy (dp) without radiation (rt) or chemotherapy (ctx), to 65% from 37% for dp plus rt or ctx, to 60% from 44% for Whipple-only, and to 50% from 36% for Whipple plus rt or ctx. Lastly, 5-year survival improved to 81% from 52% for dp only, to 41% from 12% for dp plus rt or ctx, to 49% from 25% for Whipple-only, and to 26% from 12% for Whipple plus rt or ctx. Conclusions: Most cases of pcc continue to be diagnosed at a late stage, with poor short-term and long-term prognoses. After adjustment for patient age, sex, and year of diagnosis, the survival for stage i tumours and for surgical modalities increased over time. Further research is needed to identify the reasons for improvement in survival during the study period.


Asunto(s)
Neoplasias Pancreáticas/terapia , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/mortalidad , Estudios Retrospectivos , Análisis de Supervivencia , Neoplasias Pancreáticas
6.
Sci Rep ; 9(1): 15053, 2019 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-31636311

RESUMEN

Chronic Obstructive Pulmonary Disease (COPD) is a progressive lung disease largely caused by cigarette smoking (CS) and is characterized by lung inflammation and airflow limitation that is not fully reversible. Approximately 50% of people with COPD die of a cardiovascular comorbidity and current pharmacological strategies provide little benefit. Therefore, drugs that target the lung and the cardiovascular system concurrently may be an advantageous therapeutic strategy. The aim of this study was to see whether losartan, an angiotensin-II AT1a receptor antagonist widely used to treat hypertension associated with cardiovascular disease, protects against CS-induced lung inflammation in mice. Male BALB/c mice were exposed to CS for 8 weeks and treated with either losartan (30 mg/kg) or vehicle daily. Mice were euthanized and bronchoalveolar lavage fluid (BALF) inflammation, and whole lung cytokine, chemokine and protease mRNA expression assessed. CS caused significant increases in BALF total cells, macrophages, neutrophils and whole lung IL-6, TNF-α, CXCL-1, IL-17A and MMP12 mRNA expression compared to sham-exposed mice. However, losartan only reduced CS-induced increases in IL-6 mRNA expression. Angiotensin-II receptor expression was reduced in lung tissue from CS-exposed mice. In conclusion, losartan did not inhibit CS-induced BALF cellularity despite reducing whole lung IL-6 mRNA and Ang-II receptor expression.


Asunto(s)
Fumar Cigarrillos/efectos adversos , Losartán/farmacología , Neumonía/etiología , Animales , Líquido del Lavado Bronquioalveolar , Quimiocinas/genética , Quimiocinas/metabolismo , Conducta de Ingestión de Líquido/efectos de los fármacos , Conducta Alimentaria/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Mediadores de Inflamación/metabolismo , Pulmón/efectos de los fármacos , Pulmón/patología , Masculino , Ratones Endogámicos BALB C , Tamaño de los Órganos/efectos de los fármacos , Neumonía/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo
7.
Curr Oncol ; 23(Suppl 1): S42-51, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26985145

RESUMEN

BACKGROUND: Research has demonstrated that increases in palliative homecare nursing are associated with a reduction in the rate of subsequent hospitalizations. However, little evidence is available about the cost-savings potential of palliative nursing when accounting for both increased nursing costs and potentially reduced hospital costs. METHODS: Our retrospective cohort study included cancer decedents from British Columbia, Ontario, and Nova Scotia who received any palliative nursing in the last 6 months of life. A Poisson regression analysis was used to determine the association of increased nursing costs (in 2-week blocks) on the relative average hospital costs in the subsequent 2-week block and on the overall total cost (hospital costs plus nursing costs in the preceding 2-week block). RESULTS: The cohort included 58,022 cancer decedents. Results of the analysis for the last month of life showed an association between increased nursing costs and decreased relative hospital costs in comparisons with a reference group (>0 to 1 hour nursing in the block): the maximum decrease was 55% for Ontario, 31% for British Columbia, and 38% for Nova Scotia. Also, increased nursing costs in the last month were almost always associated with lower total costs in comparison with the reference. For example, cost savings per person-block ranged from $376 (>10 nursing hours) to $1,124 (>4 to 6 nursing hours) in British Columbia. CONCLUSIONS: In the last month of life, increased palliative nursing costs (compared with costs for >0 to 1 hour of nursing in the block) were associated with lower relative hospital costs and a lower total cost in a subsequent block. Our research suggests a cost-savings potential associated with increased community-based palliative nursing.

8.
Sci Rep ; 6: 20983, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26877172

RESUMEN

Influenza A virus (IAV) infections are a common cause of acute exacerbations of chronic obstructive pulmonary disease (AECOPD). Oxidative stress is increased in COPD, IAV-induced lung inflammation and AECOPD. Therefore, we investigated whether targeting oxidative stress with the Nox2 oxidase inhibitors and ROS scavengers, apocynin and ebselen could ameliorate lung inflammation in a mouse model of AECOPD. Male BALB/c mice were exposed to cigarette smoke (CS) generated from 9 cigarettes per day for 4 days. On day 5, mice were infected with 1 × 10(4.5) PFUs of the IAV Mem71 (H3N1). BALF inflammation, viral titers, superoxide production and whole lung cytokine, chemokine and protease mRNA expression were assessed 3 and 7 days post infection. IAV infection resulted in a greater increase in BALF inflammation in mice that had been exposed to CS compared to non-smoking mice. This increase in BALF inflammation in CS-exposed mice caused by IAV infection was associated with elevated gene expression of pro-inflammatory cytokines, chemokines and proteases, compared to CS alone mice. Apocynin and ebselen significantly reduced the exacerbated BALF inflammation and pro-inflammatory cytokine, chemokine and protease expression caused by IAV infection in CS mice. Targeting oxidative stress using apocynin and ebselen reduces IAV-induced lung inflammation in CS-exposed mice and may be therapeutically exploited to alleviate AECOPD.


Asunto(s)
Acetofenonas/administración & dosificación , Azoles/administración & dosificación , Compuestos de Organoselenio/administración & dosificación , Neumonía/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Animales , Modelos Animales de Enfermedad , Humanos , Virus de la Influenza A/efectos de los fármacos , Virus de la Influenza A/patogenicidad , Isoindoles , Masculino , Ratones , Estrés Oxidativo/efectos de los fármacos , Neumonía/patología , Neumonía/virología , Enfermedad Pulmonar Obstructiva Crónica/patología , Enfermedad Pulmonar Obstructiva Crónica/virología , Humo/efectos adversos , Fumar/efectos adversos , Nicotiana/efectos adversos
9.
Curr Oncol ; 22(5): 341-55, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26628867

RESUMEN

BACKGROUND: The quality of data comparing care at the end of life (eol) in cancer patients across Canada is poor. This project used identical cohorts and definitions to evaluate quality indicators for eol care in British Columbia, Alberta, Ontario, and Nova Scotia. METHODS: This retrospective cohort study of cancer decedents during fiscal years 2004-2009 used administrative health care data to examine health service quality indicators commonly used and previously identified as important to quality eol care: emergency department use, hospitalizations, intensive care unit admissions, chemotherapy, physician house calls, and home care visits near the eol, as well as death in hospital. Crude and standardized rates were calculated. In each province, two separate multivariable logistic regression models examined factors associated with receiving aggressive or supportive care. RESULTS: Overall, among the identified 200,285 cancer patients who died of their disease, 54% died in a hospital, with British Columbia having the lowest standardized rate of such deaths (50.2%). Emergency department use at eol ranged from 30.7% in Nova Scotia to 47.9% in Ontario. Of all patients, 8.7% received aggressive care (similar across all provinces), and 46.3% received supportive care (range: 41.2% in Nova Scotia to 61.8% in British Columbia). Lower neighbourhood income was consistently associated with a decreased likelihood of supportive care receipt. INTERPRETATION: We successfully used administrative health care data from four Canadian provinces to create identical cohorts with commonly defined indicators. This work is an important step toward maturing the field of eol care in Canada. Future work in this arena would be facilitated by national-level data-sharing arrangements.

10.
Support Care Cancer ; 23(10): 3025-32, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25711657

RESUMEN

BACKGROUND: In 2007, the provincial cancer agency in Ontario, Canada initiated a wide-scale program to screen for symptoms in the cancer population using the Edmonton Symptom Assessment Scale (ESAS). The purpose of this study is to evaluate the impact of screening with ESAS on emergency department (ED) visit rates in women with breast cancer receiving adjuvant chemotherapy. PATIENTS AND METHODS: This retrospective cohort study used linked administrative health care data from across the province of Ontario, Canada. The cohort included all women aged ≥18 who were diagnosed with stage I-III breast cancer between January 2007 and December 2009 and received adjuvant chemotherapy within 6 months of diagnosis. Using an adjusted recurrent event model, we examined the association of screening with ESAS at a clinic visit on the ED visit rate. RESULTS: The relative rate of ED visits was 0.57 when prior ESAS screening occurred compared to when it did not. The relative rate of ED visits was 0.83 when the prior number of ESAS screens was modeled as a continuous variable. Alternatively stated, the rate of ED visits was 43 % lower among patients previously screened with ESAS compared to those not previously screened. For each additional prior ESAS assessment, there was a 17 % decreased rate of ED visits. CONCLUSIONS: Our results demonstrate that screening with ESAS is associated with decreased ED visits. To our knowledge, this is the first report on the effectiveness of routinely documenting a patient reported outcome on ED visits, in a real-world setting.


Asunto(s)
Atención Ambulatoria/tendencias , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Estudios de Cohortes , Detección Precoz del Cáncer , Servicio de Urgencia en Hospital , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Evaluación de Síntomas , Adulto Joven
11.
J Appl Microbiol ; 118(5): 1180-90, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25688886

RESUMEN

AIMS: This study investigates the antagonistic effects of the probiotic strains Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 against vulvovaginal candidiasis (VVC)-causing Candida glabrata. METHODS AND RESULTS: Growth inhibitory activities of Lact. rhamnosus GR-1 and Lact. reuteri RC-14 strains against C. glabrata were demonstrated using a spot overlay assay and a plate-based microtitre assay. In addition, these probiotic lactobacilli strains also exhibited potent candidacidal activity against C. glabrata, as demonstrated by a LIVE/DEAD yeast viability assay performed using confocal laser scanning microscopy. The metabolic activities of all C. glabrata strains were completely shut down in response to the challenges by the probiotic lactobacilli strains. In addition, both probiotic lactobacilli strains exhibited strong autoaggregation and coaggregation phenotypes in the presence of C. glabrata, which indicate that these lactobacilli strains may exert their probiotic effects through the formation of aggregates and, thus the consequent prevention of colonization by C. glabrata. CONCLUSIONS: Probiotic Lact. rhamnosus GR-1 and Lact. reuteri RC-14 strains exhibited potent antagonistic activities against all of the tested C. glabrata strains. These lactobacilli exhibited antifungal effects, including those attributed to their aggregation abilities, and their presence caused the cessation of growth and eventual cell death of C. glabrata. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first study to report on the antagonistic effects of these probiotic lactobacilli strains against the non-Candida albicans Candida (NCAC) species C. glabrata.


Asunto(s)
Antibiosis , Candida glabrata/crecimiento & desarrollo , Candidiasis Vulvovaginal/microbiología , Lacticaseibacillus rhamnosus/fisiología , Limosilactobacillus reuteri/fisiología , Probióticos/administración & dosificación , Candida glabrata/efectos de los fármacos , Femenino , Humanos
12.
Sci Transl Med ; 7(269): 269ra3, 2015 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-25568071

RESUMEN

New chemotherapeutic agents are urgently required to combat the global spread of multidrug-resistant tuberculosis (MDR-TB). The mycobacterial enoyl reductase InhA is one of the few clinically validated targets in tuberculosis drug discovery. We report the identification of a new class of direct InhA inhibitors, the 4-hydroxy-2-pyridones, using phenotypic high-throughput whole-cell screening. This class of orally active compounds showed potent bactericidal activity against common isoniazid-resistant TB clinical isolates. Biophysical studies revealed that 4-hydroxy-2-pyridones bound specifically to InhA in an NADH (reduced form of nicotinamide adenine dinucleotide)-dependent manner and blocked the enoyl substrate-binding pocket. The lead compound NITD-916 directly blocked InhA in a dose-dependent manner and showed in vivo efficacy in acute and established mouse models of Mycobacterium tuberculosis infection. Collectively, our structural and biochemical data open up new avenues for rational structure-guided optimization of the 4-hydroxy-2-pyridone class of compounds for the treatment of MDR-TB.


Asunto(s)
Antituberculosos/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Inhibidores Enzimáticos/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/enzimología , Oxidorreductasas/antagonistas & inhibidores , Animales , Antituberculosos/química , Proteínas Bacterianas/metabolismo , Fenómenos Biofísicos/efectos de los fármacos , Cristalografía por Rayos X , Modelos Animales de Enfermedad , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Inhibidores Enzimáticos/química , Ratones Endogámicos BALB C , Modelos Moleculares , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Oxidorreductasas/metabolismo , Piridinas/química , Piridinas/farmacología , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
13.
Sci Transl Med ; 5(214): 214ra168, 2013 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-24307692

RESUMEN

New chemotherapeutic compounds against multidrug-resistant Mycobacterium tuberculosis (Mtb) are urgently needed to combat drug resistance in tuberculosis (TB). We have identified and characterized the indolcarboxamides as a new class of antitubercular bactericidal agent. Genetic and lipid profiling studies identified the likely molecular target of indolcarboxamides as MmpL3, a transporter of trehalose monomycolate that is essential for mycobacterial cell wall biosynthesis. Two lead candidates, NITD-304 and NITD-349, showed potent activity against both drug-sensitive and multidrug-resistant clinical isolates of Mtb. Promising pharmacokinetic profiles of both compounds after oral dosing in several species enabled further evaluation for efficacy and safety. NITD-304 and NITD-349 were efficacious in treating both acute and chronic Mtb infections in mouse efficacy models. Furthermore, dosing of NITD-304 and NITD-349 for 2 weeks in exploratory rat toxicology studies revealed a promising safety margin. Finally, neither compound inhibited the activity of major cytochrome P-450 enzymes or the hERG (human ether-a-go-go related gene) channel. These results suggest that NITD-304 and NITD-349 should undergo further development as a potential treatment for multidrug-resistant TB.


Asunto(s)
Antituberculosos/farmacología , Indoles/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Administración Oral , Animales , Antituberculosos/administración & dosificación , Antituberculosos/farmacocinética , Antituberculosos/toxicidad , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/metabolismo , Disponibilidad Biológica , Modelos Animales de Enfermedad , Perros , Relación Dosis-Respuesta a Droga , Farmacorresistencia Bacteriana Múltiple/genética , Humanos , Indoles/administración & dosificación , Indoles/farmacocinética , Indoles/toxicidad , Inyecciones Intravenosas , Proteínas de Transporte de Membrana/efectos de los fármacos , Proteínas de Transporte de Membrana/metabolismo , Ratones , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/crecimiento & desarrollo , Mycobacterium tuberculosis/metabolismo , Ratas , Ratas Wistar , Tuberculosis Resistente a Múltiples Medicamentos/diagnóstico , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
14.
Parasit Vectors ; 5: 88, 2012 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-22564445

RESUMEN

BACKGROUND: Canine hookworm infection is endemic in Southeast Asian countries with a prevalence ranging from 70% to 100%, with zoonotic transmission representing a potentially significant public health concern. However, there are limited data available on the prevalence of canine hookworms in Malaysia. This study was conducted to determine the prevalence of hookworm and Ancylostoma species among dogs in Malaysia. METHODS: Faecal samples were collected from 221 dogs living in urban areas, rural areas and animal shelters in Selangor. Faecal samples were processed using the formal-ether concentration technique followed by wet mount preparation and iodine staining for the detection of hookworm eggs. Samples positive for hookworm eggs were examined using PCR, targeting ITS2 and 28 s rRNA region, and subsequently sequenced in both directions. The sequences were phylogenetically analysed using MrBayes for Bayesian Inference. RESULTS: The overall prevalence of hookworm among dogs was 48% (95%CI; 41.41-54.95). Rural stray dogs had the highest prevalence 71.4% (95%CI; 61.13-81.49) followed by urban stray dogs, recording 48% (95%CI; 34.15-61.85) and lastly dogs in shelters with 28.7% (95%CI; 19.56-37.84). Logistic regression identified rural stray dogs as a high risk group (OR = 4.55, 95%; 2.50-8.31) and keeping dogs in shelters as a protective factor (OR = 0.24, 95%; 0.14-0.43). Molecular methods identified both Ancylostoma ceylanicum and Ancylostoma caninum with A. ceylanicum being predominant among urban stray dogs. Rural dogs had a higher prevalence of A. caninum than A. ceylanicum, while both species showed equal distribution among dogs in shelters. Phylogenetic analysis placed A. ceylanicum isolated from dogs in one group with A. ceylanicum human isolates. CONCLUSION: This study indicates that dogs have the potential to act as reservoir hosts of human hookworm infection in Malaysia. This finding necessitates the inclusion of dogs in any interventions to combat hookworm in the country.


Asunto(s)
Ancylostomatoidea , Enfermedades de los Perros/parasitología , Infecciones por Uncinaria/veterinaria , Zoonosis/transmisión , Animales , ADN Intergénico/genética , Enfermedades de los Perros/epidemiología , Perros , Heces/parasitología , Infecciones por Uncinaria/epidemiología , Infecciones por Uncinaria/parasitología , Humanos , Malasia/epidemiología , Oportunidad Relativa , Filogenia , Factores de Riesgo , Especificidad de la Especie
15.
Cell Prolif ; 45(2): 132-9, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22309282

RESUMEN

BACKGROUND: Mesenchymal stem cells (MSC) have great potential in regenerative medicine, immunotherapy and gene therapy due to their unique properties of self-renewal, high plasticity, immune modulation and ease for genetic modification. However, production of MSC at sufficient clinical scale remains an issue as in vitro generation of MSC inadequately fulfils the demand with respect to patients. OBJECTIVES: This study has aimed to establish optimum conditions to generate and characterize MSC from human umbilical cord (UC-MSC). MATERIALS AND METHODS: To optimize MSC population growth, basic fibroblast growth factor (bFGF) was utilized in culture media. Effects of bFGF on expansion kinetics, cell cycle, survival of UC-MSC, cytokine secretion, expression of early stem-cell markers and immunomodulation were investigated. RESULTS: bFGF supplementation profoundly enhanced UC-MSC proliferation by reducing population doubling time without altering immunophenotype and immunomodulatory function of UC-MSC. However, cell cycle studies revealed that bFGF drove the cells into the cell cycle, as a higher proportion of cells resided in S phase and progressed into M phase. Consistent with this, bFGF was shown to promote expression of cyclin D proteins and their relevant kinases to drive UC-MSC to transverse cell cycle check points, thus, committing the cells to DNA synthesis. Furthermore, supplementation with bFGF changed the cytokine profiles of the cells and reduced their apoptotic level. CONCLUSION: Our study showed that bFGF supplementation of UC-MSC culture enhanced the cells' growth kinetics without compromising their nature.


Asunto(s)
Factor 2 de Crecimiento de Fibroblastos/farmacología , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Cordón Umbilical/citología , Apoptosis/efectos de los fármacos , Comunicación Celular/inmunología , Técnicas de Cultivo de Célula , Ciclo Celular/efectos de los fármacos , Proteínas de Ciclo Celular/biosíntesis , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Citocinas/biosíntesis , Femenino , Factor 2 de Crecimiento de Fibroblastos/administración & dosificación , Humanos , Metaloproteinasa 3 de la Matriz/metabolismo , Células Madre Mesenquimatosas/inmunología , Células Madre Mesenquimatosas/metabolismo , Embarazo , Linfocitos T/inmunología , Factor A de Crecimiento Endotelial Vascular/metabolismo
16.
Eur J Clin Microbiol Infect Dis ; 31(1): 21-31, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21544694

RESUMEN

The ubiquitous Candida spp. is an opportunistic fungal pathogen which, despite treatment with antifungal drugs, can cause fatal bloodstream infections (BSIs) in immunocompromised and immunodeficient persons. Thus far, several major C. albicans virulence factors have been relatively well studied, including morphology switching and secreted degradative enzymes. However, the exact mechanism of Candida pathogenesis and the host response to invasion are still not well elucidated. The relatively recent discovery of the quorum-sensing molecule farnesol and the existence of quorum sensing as a basic regulatory phenomenon of the C. albicans population behavior has revolutionized Candida research. Through population density regulation, the quorum-sensing mechanism also controls the cellular morphology of a C. albicans population in response to environmental factors, thereby, effectively placing morphology switching downstream of quorum sensing. Thus, the quorum-sensing phenomenon has been hailed as the 'missing piece' of the pathogenicity puzzle. Here, we review what is known about Candida spp. as the etiological agents of invasive candidiasis and address our current understanding of the quorum-sensing phenomenon in relation to virulence in the host.


Asunto(s)
Candida/patogenicidad , Candidiasis Invasiva/microbiología , Percepción de Quorum , Animales , Biopelículas , Candida/citología , Candida/enzimología , Candida/fisiología , Farnesol/metabolismo , Humanos , Factores de Virulencia/metabolismo
17.
Med J Malaysia ; 65(3): 209-14, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21939170

RESUMEN

We have previously shown that mesenchymal stem cells (MSC) inhibit tumour cell proliferation, thus promising a novel therapy for treating cancers. In this study, MSC were generated from human bone marrow samples and characterised based on standard immunophenotyping. When MSC were co-cultured with BV173 and Jurkat tumour cells, the proliferation of tumour cells were profoundly inhibited in a dose dependent manner mainly via cell to cell contact interaction. Further cell cycle analysis reveals that MSC arrest tumour cell proliferation in G0/G1 phase of cell cycle thus preventing the entry of tumour cells into S phase of cell cycle.


Asunto(s)
Ciclo Celular , Proliferación Celular , Células Madre Mesenquimatosas/fisiología , Humanos , Inmunofenotipificación , Células Jurkat/citología , Células Madre Mesenquimatosas/metabolismo
18.
Clin Exp Immunol ; 155(3): 412-22, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19220831

RESUMEN

The pathological significance of the mechanisms of tumour immune-evasion and/or immunosuppression, such as loss of T cell signalling and increase in regulatory T cells (T(regs)), has not been well established in the nasopharyngeal carcinoma (NPC) microenvironment. To evaluate the T(reg) immunophenotypes in tumour-infiltrating lymphocytes (TILs), we performed a double-enzymatic immunostaining for detection of forkhead box P3 (FoxP3) and other markers including CD4, CD8, and CD25 on 64 NPC and 36 non-malignant nasopharyngeal (NP) paraffin-embedded tissues. Expression of CD3 zeta and CD3 epsilon was also determined. The prevalence of CD4(+)FoxP3(+) cells in CD4(+) T cells and the ratio of FoxP3(+)/CD8(+) were increased significantly in NPC compared with those in NP tissues (P < 0.001 and P = 0.025 respectively). Moreover, the ratio of FoxP3(+)/CD25(+)FoxP3(-) in NPC was significantly lower than that in NP tissues (P = 0.005), suggesting an imbalance favouring activated phenotype of T cells in NPC. A significant negative correlation between the abundance of FoxP3(+) and CD25(+)FoxP3(-) cells (P < 0.001) was also identified. When histological types of NPC were considered, a lower ratio of FoxP3(+)/CD25(+)FoxP3(-) was found in non-keratinizing and undifferentiated carcinomas. Increased CD4(+)FoxP3(+)/CD4(+) proportion and FoxP3(+)/CD8(+) ratio were associated with keratinizing squamous cell carcinoma. A reduced expression of CD3 zeta in TILs was found in 20.6% of the NPC tissues but none of the NP tissues. These data provide evidence for the imbalances of T(reg) and effector T cell phenotypes and down-regulation of signal-transducing molecules in TILs, supporting their role in suppression of immune response and immune evasion of NPC.


Asunto(s)
Carcinoma/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Neoplasias Nasofaríngeas/inmunología , Linfocitos T Reguladores/inmunología , Biomarcadores/análisis , Complejo CD3/análisis , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Carcinoma de Células Escamosas/inmunología , Femenino , Factores de Transcripción Forkhead/análisis , Humanos , Inmunohistoquímica , Subunidad alfa del Receptor de Interleucina-2/análisis , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Nasofaringe/inmunología , Estadísticas no Paramétricas
19.
Med J Malaysia ; 63 Suppl A: 77-8, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19024992

RESUMEN

The immune modulatory properties of mesenchymal stem cell (MSC) had brought a new insight in cell-based neotherapy. However, recent works of MSC are focused exclusively on bone marrow-derived MSC. We evaluated the immunogenicity of cord blood-derived MSC (CB-MSC) on T lymphocytes. Human peripheral blood mononuclear cells (PBMC) were prepared by density gradient separation and culture with the presence or absence of CB-MSC. PBMC were collected for activation analysis by flow cytometry at 24-, 48-, and 72- hours. The results showed that, CB-MSC does not stimulate nor inhibit T lymphocyte activation.


Asunto(s)
Médula Ósea/inmunología , Sangre Fetal/inmunología , Inmunogenética , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/inmunología , Trasplante de Células Madre de Sangre Periférica , Linfocitos T/citología , Antígenos CD , Antígenos de Diferenciación de Linfocitos T , Técnicas de Cultivo de Célula , Citometría de Flujo , Humanos , Subunidad alfa del Receptor de Interleucina-2 , Lectinas Tipo C
20.
Mycopathologia ; 159(4): 495-500, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15983734

RESUMEN

Hortaea werneckii is an environmental dematiaceous fungus found in the halophilic environment. It causes tinea nigra. We report the isolation of H. werneckii from blood and splenic abscess of two patients with acute myelomonocytic leukaemia. H. werneckii grew at room temperature but not at 37 degrees C, it was identified by biochemical tests, growth characteristics and the presence of conspicuous collarette intercalary on dividing yeast cells. The use of specific oligonucleotide primer Hor-F (5'-TGGACACCTTCA TAACTCTTG-3') and Hor-R (5'-TCACAACGCTTAGAGACGG-3') confirmed the two isolates were H. werneckii. The sequence for 281 nucleotide of HW299 and HW403 were 99% identical but differed only in one nucleotide. In vitro anti-fungal susceptibility testing showed that the isolates were resistant to amphotericin B and flucytosine.


Asunto(s)
Fungemia/microbiología , Leucemia Mielomonocítica Aguda/microbiología , Hongos Mitospóricos/genética , Hongos Mitospóricos/aislamiento & purificación , Enfermedades del Bazo/microbiología , Secuencia de Bases , ADN de Hongos/química , ADN de Hongos/genética , Femenino , Humanos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Hongos Mitospóricos/ultraestructura , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Sepsis , Alineación de Secuencia
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