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1.
Clin Transl Oncol ; 19(4): 477-488, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27718154

RESUMEN

BACKGROUND: The role of the interaction between tumor cells and inflammatory cells in gallbladder carcinoma (GBC) is unclear. Inflammatory cells exist in both the tumor immune microenvironment and the host peripheral blood circulatory system. In the current study, we examined the prognostic value of inflammatory cells in the tumor microenvironment and peripheral blood in patients with GBC. METHODS: 98 patients with GBC were recruited in this retrospective study. Using immunohistochemistry, we examined tumor-infiltrating CD3+ generic T-cells, CD8+ cytotoxic T-cells, CD45RO+ memory T-cells, and CD15+ neutrophils. Peripheral venous blood samples were also collected, and absolute neutrophil count (ANC), absolute lymphocyte count (ALC) and neutrophil/lymphocyte ratio (NLR) were measured. The relationships between these variables and patient outcome were evaluated. RESULTS: Survival analysis revealed that the density of CD3+ cell infiltrates in the tumor microenvironment was positively correlated with overall survival (OS) and the density of CD15+ cell infiltrates was negatively correlated with the OS. The combined analysis showed that a high density of CD3+ cell infiltrates combined with a low density of CD15+ cell infiltrates was an independent prognostic factor for GBC. In peripheral blood, survival analysis suggested that ANC and NLR were negatively correlated, while ALC was positively correlated with OS. Multivariate survival analysis showed that NLR was an independent prognostic factor for gallbladder cancer prognosis. CONCLUSIONS: The results indicate that the combination of high density of CD3+ cell infiltrates combined with a low density of CD15+ cell infiltrates in tumor samples and pretreatment peripheral blood NLR were independent prognostic factors in patients with GBC.


Asunto(s)
Carcinoma de Células Escamosas/inmunología , Neoplasias de la Vesícula Biliar/inmunología , Inflamación/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Microambiente Tumoral/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/secundario , Femenino , Estudios de Seguimiento , Neoplasias de la Vesícula Biliar/sangre , Neoplasias de la Vesícula Biliar/patología , Humanos , Técnicas para Inmunoenzimas , Inflamación/sangre , Inflamación/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Neutrófilos/inmunología , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
2.
Clin Transl Oncol ; 19(3): 332-340, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27468867

RESUMEN

PURPOSE: Changes in EGFR profiles of non small cell lung cancer (NSCLC) patients correlates to clinical outcome. Extracting quality tumor tissue remains a challenge for molecular profiling. Our study aims to ascertain the clinical relevance of urinary cell free DNA as an alternative tumor material source. METHODS: 150 patients with activating EGFR mutation and received EGFR-TKIs were recruited to participate in the serial monitoring study. Matched primary tumor samples were taken together with blood and urine specimens before the initiation of TKIs. The EGFR mutation testing was performed and quantified using ddPCR. For serial time point measurements, urine and blood samples were extracted at 1-month intervals for duration of 9 months. RESULTS: Urinary ctDNA yielded a close agreement of 88 % on EGFR mutation status when compared to primary tissue at baseline. Almost all samples detected via urine specimens were uncovered in plasma samples. Analysis of urinary cell free DNA at different time points showed a strong correlation to treatment efficacy. Interestingly, a secondary EGFR mutation T790M was detected for 53 % of the patients during monitoring. The results were corroborated with the plasma ctDNA analysis. The T790M+ group had a reduced median survival when compared to the wildtype group. CONCLUSION: Urinary cell free DNA may be a potential alternative to conventional primary tissue based EGFR mutation testing. Our findings showed that the assay sensitivity was comparable to results from blood plasma. Urinary samples being noninvasive and readily available have clinical utility for monitoring of EGFR TKI treatment.


Asunto(s)
Biomarcadores de Tumor/orina , Carcinoma de Pulmón de Células no Pequeñas/orina , ADN de Neoplasias/orina , Receptores ErbB/genética , Mutación/genética , Inhibidores de Proteínas Quinasas/uso terapéutico , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/patología , Adenocarcinoma/orina , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Estudios de Casos y Controles , ADN de Neoplasias/genética , Receptores ErbB/orina , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/orina , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Células Neoplásicas Circulantes/efectos de los fármacos , Células Neoplásicas Circulantes/metabolismo , Reacción en Cadena de la Polimerasa , Pronóstico , Tasa de Supervivencia
3.
Genet Mol Res ; 15(2)2016 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-27323013

RESUMEN

Recently genome-wide association studies on East Asian populations reported an association between diabetes and several single nucleotide polymorphisms (SNPs) in a 40-kb linkage disequilibrium block in intron 15 of KCNQ1. However, the association between KCNQ1 variants and type 2 diabetes mellitus (T2DM) in Chinese Kazakh populations is unknown. We investigated the relationship between rs2237892 and rs2237895 SNPs in KCNQ1 and susceptibility to and clinical characteristics of T2DM in 100 Chinese Kazakh T2DM subjects and 100 healthy subjects. SNPs were genotyped by polymerase chain reaction-restriction fragment length polymorphism and the main anthropometric and biochemical parameters of individuals were assessed in the genotype groups (rs2237892: CC, CT, or TT, and rs2237895: AA, AC, or CC). Genotype distribution and allele frequencies of these two SNPs were not significantly different between T2DM and control groups (P > 0.05). The frequencies of CT and TT genotypes and T allele for the rs2237892 SNP in females with T2DM were significantly higher than that in the control group (genotype: P = 0.016, allele: P = 0.004). However, there were no significant differences among individuals with different genotypes with respect to the rs2237895 SNP (P > 0.05). The main anthropometric and biochemical parameters did not correlate with the rs2237892 or rs2237895 SNPs in the T2DM group (P > 0.05). Thus, the T allele-containing genotypes of the rs2237892 SNP in KCNQ1 may increase the susceptibility to T2DM in female Chinese Kazakh individuals, whereas the rs2237895 SNP may not be associated with T2DM in the Chinese Kazakh population.


Asunto(s)
Canal de Potasio KCNQ1/genética , Adulto , Alelos , Pueblo Asiatico/genética , Estudios de Casos y Controles , China , Diabetes Mellitus Tipo 2/genética , Etnicidad/genética , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genética de Población , Humanos , Canal de Potasio KCNQ1/metabolismo , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple
4.
Genet Mol Res ; 14(4): 15177-87, 2015 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-26634481

RESUMEN

This study aimed to investigate cytosine methylation profiles in different tobacco (Nicotiana tabacum) cultivars grown in China. Methylation-sensitive amplified polymorphism was used to analyze genome-wide global methylation profiles in four tobacco cultivars (Yunyan 85, NC89, K326, and Yunyan 87). Amplicons with methylated C motifs were cloned by reamplified polymerase chain reaction, sequenced, and analyzed. The results show that geographical location had a greater effect on methylation patterns in the tobacco genome than did sampling time. Analysis of the CG dinucleotide distribution in methylation-sensitive polymorphic restriction fragments suggested that a CpG dinucleotide cluster-enriched area is a possible site of cytosine methylation in the tobacco genome. The sequence alignments of the Nia1 gene (that encodes nitrate reductase) in Yunyan 87 in different regions indicate that a C-T transition might be responsible for the tobacco phenotype. T-C nucleotide replacement might also be responsible for the tobacco phenotype and may be influenced by geographical location.


Asunto(s)
Citosina/metabolismo , Metilación de ADN/genética , Nicotiana/genética , Nicotiana/metabolismo , Polimorfismo Genético/genética , China , Islas de CpG/genética , ADN de Plantas/genética , Genes de Plantas/genética , Genoma de Planta/genética , Nitrato-Reductasa/genética , Reacción en Cadena de la Polimerasa/métodos
5.
Genet Mol Res ; 14(4): 14615-28, 2015 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-26600521

RESUMEN

The aim of this study is to investigate the ability to prenatally diagnose phenylketonuria (PKU) by using phenylalanine hydroxylase (PAH) gene mutation analysis combined with short tandem repeat (STR) linkage analysis in 118 fetuses from 112 Chinese families. Genomic DNA was extracted from the peripheral blood from members of 112 families and the exons and exon-intron boundaries of the PAH gene were amplified by PCR. PCR products were analyzed by bi-directional Sanger sequencing and multiplex ligation-dependent probe amplification (MLPA). The three variable number of tandem repeat (VNTR) markers PAH-1, PAH-26, PAH-32 were used in the prenatal diagnosis for the PKU families. We identified a spectrum of 63 different mutations, including 61 point mutations and indels, two large exon deletion mutations, and five novel mutations. A substantial proportion of mutant alleles were accounted for by p.R243Q (15.62%), EX6-96AG (9.82%), p.V399V (7.59%), p.Y356X (6.70%), and p.R413P (5.36%). The same mutations were identified in 31 prenatally genotyped fetuses. We identified 58 fetuses that carried only one mutant allele and 29 fetuses that carried no mutations of PAH and were presumed normal. PAH gene mutation analysis combined with STR linkage analysis can provide rapid and accurate prenatal diagnosis for PKU families.


Asunto(s)
Fenilalanina Hidroxilasa/genética , Fenilcetonurias/genética , Diagnóstico Prenatal , Alelos , Pueblo Asiatico , Exones , Femenino , Ligamiento Genético , Genotipo , Humanos , Intrones/genética , Repeticiones de Microsatélite/genética , Fenilalanina Hidroxilasa/sangre , Fenilcetonurias/sangre , Mutación Puntual , Embarazo , Eliminación de Secuencia/genética
6.
Genet Mol Res ; 14(3): 8068-76, 2015 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-26214489

RESUMEN

It has been suggested that the angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism is linked to susceptibility to myocardial infarction (MI). In this study, we performed a meta-analysis to assess the relationship between ACE I/D polymorphism and MI in the Chinese Han population. Eight studies including a total of 1609 subjects were selected for inclusion in the analysis. The references were retrieved using the PubMed and China National Knowledge Infrastructure databases. The analyses were performed using the STATA 12.0 software. ORs and 95%CI were assessed after the collected data were pooled for analysis. There was a significant association between ACE I/D polymorphism and MI in the Chinese Han population (II vs DD: OR = 0.40, 95%CI = 0.31-0.53; II vs DI: OR = 0.72, 95%CI = 0.57-0.91; the dominant model: OR = 1.74, 95%CI = 1.41-2.16; the recessive model: OR = 0.47, 95%CI = 0.38-0.60). The sensitivity analysis further confirmed the result. Publication bias was not observed in this meta-analysis. The ACE I/D polymorphism may be a risk factor for MI in the Chinese Han population. However, larger studies with a stratified case-control population and biological characterization are needed to validate this finding.


Asunto(s)
Pueblo Asiatico/genética , Etnicidad/genética , Predisposición Genética a la Enfermedad , Mutación INDEL/genética , Infarto del Miocardio/enzimología , Infarto del Miocardio/genética , Peptidil-Dipeptidasa A/genética , Intervalos de Confianza , Humanos , Oportunidad Relativa , Sesgo de Publicación , Factores de Riesgo
7.
Genet Mol Res ; 14(2): 5922-9, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-26125791

RESUMEN

Numerous studies have evaluated the association between Arg389Gly polymorphism in the ß1 adrenergic receptor gene and heart failure risk. However, the specific association is still controversial. We performed a meta-analysis of all case-control studies that evaluated the association between Arg389Gly polymorphism and heart failure in humans. Studies were identified in the PubMed, Embase, and China National Knowledge Infrastructure databases. Two reviewers independently assessed the studies. Six case-control studies with a total of 1736 participants were included in the meta-analysis, including 882 cases with heart failure and 854 controls, and our results showed no association between the Arg389Gly polymorphism and heart failure [ArgArg vs GlyGly: odds ratio (OR) = 0.84, 95% confidence interval (CI) 0.59-1.20; ArgArg vs ArgGly: OR = 0.95, 95%CI 0.78-1.16; dominant model: OR = 1.08, 95%CI 0.89-1.31; recessive model: OR = 0.96, 95%CI 0.69-1.35]. No publication bias was found in the present study (all P values > 0.05). In conclusion, the ß1 adrenergic receptor gene Arg389Gly polymorphism might not be associated with heart failure risk. Further large and well-designed studies are needed to confirm this conclusion.


Asunto(s)
Predisposición Genética a la Enfermedad , Insuficiencia Cardíaca/genética , Hipertensión/genética , Receptores Adrenérgicos beta 1/genética , China , Femenino , Estudios de Asociación Genética , Insuficiencia Cardíaca/patología , Humanos , Hipertensión/patología , Polimorfismo de Nucleótido Simple , Factores de Riesgo
8.
Genet Mol Res ; 14(2): 6401-12, 2015 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-26125845

RESUMEN

The effects of exogenous 5-aminolevulinic acid (ALA) on photosynthesis, plant growth, and the expression of two aquaporin genes in tomato seedlings under control and salinity conditions were investigated. Exogenous ALA application significantly improved net photosynthetic rate (Pn), total chlorophyll content, and plant biomass accumulation of tomato seedlings under salinity stress. As revealed by real-time PCR analyses, after treatment with ALA alone, expression of both LePIP1 and LePIP2 in the two tomato cultivars was up-regulated at 2 h and subsequently decreased to normal levels. Under salinity stress, transcript levels of LePIP1 in both leaves and roots of salt-sensitive cultivars (cv. Zhongza No.9) increased significantly and were considerably higher than in cultivars exposed to ALA alone. In contrast, the expression levels of LePIP1 and LePIP2 in cvs. Jinpeng No.1 cultivars were slightly lower under salinity stress than under ALA treatment. In addition, transcript levels of both LePIP1 and LePIP2 in the roots of Jinpeng No. 1 cultivars were considerably lower than those in the roots of Zhongza No. 9 cultivars under salinity stress, regardless of ALA supplementation, implying that Jinpeng No. 1 cultivars had a better capacity to maintain membrane intrinsic protein stability. Further, ALA application distinctly counteracted the up- or down-regulation of LePIP1 and LePIP2 in both cultivars under salinity stress, in accordance with the improvements instomatal conductance, transpiration rate, and Pn of tomato leaves. The results presented here indicate that ALA controls aquaporin expression, thus, presumably ALA regulates water homeostasis and enhances salt tolerance of tomato seedlings.


Asunto(s)
Fotosíntesis/efectos de los fármacos , Tolerancia a la Sal/efectos de los fármacos , Plantones/genética , Solanum lycopersicum/crecimiento & desarrollo , Ácido Aminolevulínico/farmacología , Clorofila/metabolismo , Solanum lycopersicum/efectos de los fármacos , Fotosíntesis/genética , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Salinidad , Plantones/efectos de los fármacos , Estrés Fisiológico/efectos de los fármacos
9.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;48(6): 486-492, 06/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-748219

RESUMEN

The objective of this study was to determine the expression of miR-483 and miR-483* and the relationship among them, their host gene (Igf2), and other cytokines in a murine model of renal fibrosis. The extent of renal fibrosis was visualized using Masson staining, and fibrosis was scored 3 days and 1 and 2 weeks after unilateral ureteral obstruction (UUO). Expression of miR-483, miR-483* and various cytokine mRNAs was detected by real-time polymerase chain reaction (PCR). Expression of miR-483 and miR-483* was significantly upregulated in the UUO model, particularly miR-483 expression was the greatest 2 weeks after surgery. Additionally, miR-483 and miR-483* expression negatively correlated with Bmp7 expression and positively correlated with Igf2, Tgfβ, Hgf, and Ctgf expression, as determined by Pearson's correlation analysis. Hgf expression significantly increased at 1 and 2 weeks after the surgery compared to the control group. This study showed that miR-483 and miR-483* expression was upregulated in a murine UUO model. These data suggest that miR-483 and miR-483* play a role in renal fibrosis and that miR-483* may interact with miR-483 in renal fibrosis. Thus, these miRNAs may play a role in the pathogenesis of renal fibrosis and coexpression of their host gene Igf2.


Asunto(s)
Animales , Masculino , Ratones , Expresión Génica , Intrones , Factor II del Crecimiento Similar a la Insulina/genética , MicroARNs , Obstrucción Ureteral/genética , Obstrucción Ureteral/patología , Western Blotting , Citocinas/genética , Modelos Animales de Enfermedad , Fibrosis/genética , Riñón/patología , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Tiempo
10.
Braz J Med Biol Res ; 48(6): 486-92, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25831208

RESUMEN

The objective of this study was to determine the expression of miR-483 and miR-483* and the relationship among them, their host gene (Igf2), and other cytokines in a murine model of renal fibrosis. The extent of renal fibrosis was visualized using Masson staining, and fibrosis was scored 3 days and 1 and 2 weeks after unilateral ureteral obstruction (UUO). Expression of miR-483, miR-483* and various cytokine mRNAs was detected by real-time polymerase chain reaction (PCR). Expression of miR-483 and miR-483* was significantly upregulated in the UUO model, particularly miR-483 expression was the greatest 2 weeks after surgery. Additionally, miR-483 and miR-483* expression negatively correlated with Bmp7 expression and positively correlated with Igf2, Tgfß, Hgf, and Ctgf expression, as determined by Pearson's correlation analysis. Hgf expression significantly increased at 1 and 2 weeks after the surgery compared to the control group. This study showed that miR-483 and miR-483* expression was upregulated in a murine UUO model. These data suggest that miR-483 and miR-483* play a role in renal fibrosis and that miR-483* may interact with miR-483 in renal fibrosis. Thus, these miRNAs may play a role in the pathogenesis of renal fibrosis and coexpression of their host gene Igf2.


Asunto(s)
Expresión Génica , Factor II del Crecimiento Similar a la Insulina/genética , Intrones , MicroARNs , Obstrucción Ureteral/genética , Obstrucción Ureteral/patología , Animales , Western Blotting , Citocinas/genética , Modelos Animales de Enfermedad , Fibrosis/genética , Riñón/patología , Masculino , Ratones , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Tiempo
11.
Genet Mol Res ; 10(3): 1696-700, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21863563

RESUMEN

The Asiatic topmouth gudgeon, Pseudorasbora parva, is recognized as one of the most invasive fish species in many countries outside of Asia. We isolated and characterized 19 microsatellite loci from P. parva. The polymorphism of these 19 loci was tested on 40 individuals of P. parva sampled from a wild population located in Ezhou, Hubei province of China. The loci had 5 to 11 alleles, with a mean of 7.7 at each locus; 11 loci conformed to Hardy-Weinberg equilibrium. The expected and observed heterozygosities ranged from 0.237 to 0.973 and from 0.647 to 0.914, respectively. All microsatellite loci were in linkage equilibrium. These microsatellite markers are potentially useful for the assessment of population genetic structure during invasion and dispersal of P. parva in new habitats.


Asunto(s)
Cyprinidae/genética , Repeticiones de Microsatélite , Polimorfismo Genético , Alelos , Animales , Heterocigoto , Desequilibrio de Ligamiento
12.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;41(1): 26-33, Jan. 2008. ilus
Artículo en Inglés | LILACS | ID: lil-469975

RESUMEN

The proposed role of Niemann-Pick type C1 protein (NPC1) in the delivery of low-density lipoprotein (LDL) cholesterol to the sterol regulatory element binding protein (SREBP):SREBP cleavage activation protein (SCAP) complex in the endoplasmic reticulum has been largely based on indirect studies and remains contentious. The major aim of the present study was to assess whether NPC1 is involved in the delivery of LDL cholesterol to the SREBP:SCAP complex. A cell line stably expressing green fluorescence protein-SCAP was cultured in the presence of U18666A, which can induce a Niemann-Pick type C disease phenotype, in order to locate the SREBP:SCAP complex by fluorescence microscopy. Our major finding was that defective NPC1 caused a delay in the ability of LDL cholesterol to suppress SREBP processing. This was shown in a time-course experiment by the effect of LDL on green fluorescence protein-SCAP movement when cells were treated with pharmacological agents to induce a Niemann-Pick type C disease phenotype. We demonstrated directly by fluorescence microscopy that defective NPC1 causes a delay in LDL cholesterol delivery to the endoplasmic reticulum where SCAP senses cholesterol.


Asunto(s)
Animales , Proteínas Portadoras/fisiología , LDL-Colesterol/metabolismo , Retículo Endoplásmico/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Glicoproteínas de Membrana/fisiología , Proteínas de la Membrana/metabolismo , Enfermedades de Niemann-Pick/etiología , Línea Celular , Microscopía Fluorescente , Enfermedades de Niemann-Pick/metabolismo , Fenotipo
13.
Braz J Med Biol Res ; 41(1): 26-33, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18060319

RESUMEN

The proposed role of Niemann-Pick type C1 protein (NPC1) in the delivery of low-density lipoprotein (LDL) cholesterol to the sterol regulatory element binding protein (SREBP):SREBP cleavage activation protein (SCAP) complex in the endoplasmic reticulum has been largely based on indirect studies and remains contentious. The major aim of the present study was to assess whether NPC1 is involved in the delivery of LDL cholesterol to the SREBP:SCAP complex. A cell line stably expressing green fluorescence protein-SCAP was cultured in the presence of U18666A, which can induce a Niemann-Pick type C disease phenotype, in order to locate the SREBP:SCAP complex by fluorescence microscopy. Our major finding was that defective NPC1 caused a delay in the ability of LDL cholesterol to suppress SREBP processing. This was shown in a time-course experiment by the effect of LDL on green fluorescence protein-SCAP movement when cells were treated with pharmacological agents to induce a Niemann-Pick type C disease phenotype. We demonstrated directly by fluorescence microscopy that defective NPC1 causes a delay in LDL cholesterol delivery to the endoplasmic reticulum where SCAP senses cholesterol.


Asunto(s)
Proteínas Portadoras/fisiología , LDL-Colesterol/metabolismo , Retículo Endoplásmico/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Glicoproteínas de Membrana/fisiología , Proteínas de la Membrana/metabolismo , Enfermedades de Niemann-Pick/etiología , Animales , Línea Celular , Microscopía Fluorescente , Proteína Niemann-Pick C1 , Enfermedades de Niemann-Pick/metabolismo , Fenotipo
14.
Infect Control Hosp Epidemiol ; 22(7): 443-8, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11583214

RESUMEN

OBJECTIVE: To evaluate the possible presence of vancomycin-resistant Staphylococcus aureus (VRSA) in a Brazilian hospital. DESIGN: Epidemiological and laboratory investigation of nosocomial VRSA. METHODS: 140 methicillin-resistant S aureus strains isolated between November 1998 and October 1999 were screened for susceptibility to vancomycin. The screening was carried out by using brain-heart infusion agar (BHIA) supplemented with 4, 6, and 8 microg/mL of vancomycin. The minimum inhibitory concentration (MIC) determination was carried out as standardized by the National Committee for Clinical Laboratory Standards using the broth macrodilution, agar-plate dilution, and E-test methods. PATIENTS: Hospitalized patients exposed to vancomycin. RESULTS: 5 of the 140 isolates had a vancomycin MIC of 8 microg/mL by broth macrodilution, agar plate dilution, and E-test methods. Four VRSA strains were isolated from patients in a burn unit who had been treated with vancomycin for more than 30 days, and one from an orthopedic unit patient who had received vancomycin treatment for 7 days. Pulsed-field gel electrophoresis characterized four of the VRSA strains as belonging to the Brazilian endemic clone. All five strains were negative for vanA, vanB, and vanC genes by polymerase chain reaction. Transmission electron microscopy of the five strains revealed significantly thickened cell walls. One patient died due to infection caused by the VRSA strain. CONCLUSIONS: This is the first report of isolation of VRSA in Brazil and the first report of isolation of multiple VRSA strains from one facility over a relatively short period of time. This alerts us to the possibility that VRSA may be capable of nosocomial transfer if adequate hospital infection control measures are not taken.


Asunto(s)
Infección Hospitalaria/tratamiento farmacológico , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/aislamiento & purificación , Resistencia a la Vancomicina , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Brasil , Infección Hospitalaria/prevención & control , Femenino , Hospitales Públicos , Humanos , Control de Infecciones/métodos , Masculino , Resistencia a la Meticilina , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas/prevención & control , Vancomicina/farmacología , Vancomicina/uso terapéutico
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