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1.
Scand J Med Sci Sports ; 28(1): 29-39, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28453899

RESUMEN

Delayed onset muscle soreness (DOMS) occurs within 1-2 days after eccentric exercise, but the mechanism mediating hypersensitivity is unclear. This study hypothesized that eccentric exercise reduces the blood flow response following muscle contractions and cuff occlusion, which may result in accumulated algesic substances being a part of the sensitization in DOMS. Twelve healthy subjects (five women) performed dorsiflexion exercise (five sets of 10 repeated eccentric contractions) in one leg, while the contralateral leg was the control. The maximal voluntary contraction (MVC) of the tibialis anterior muscle was recorded. Blood flow was assessed by ultrasound Doppler on the anterior tibialis artery (ATA) and within the anterior tibialis muscle tissue before and immediately after 1-second MVC, 5-seconds MVC, and 5-minutes thigh cuff occlusion. Pressure pain thresholds (PPTs) were recorded on the tibialis anterior muscle. All measures were done bilaterally at day 0 (pre-exercise), day 2, and day 6 (post-exercise). Subjects scored the muscle soreness on a Likert scale for 6 days. Eccentric exercise increased Likert scores at day 1 and day 2 compared with day 0 (P<.001). Compared with pre-exercise (day 0), reduced PPT (~25%, P<.002), MVC (~22%, P<.002), ATA diameter (~8%, P<.002), ATA post-contraction/occlusion blood flow (~16%, P<.04), and intramuscular peak blood flow (~23%, P<.03) were found in the DOMS leg on day 2 but not in the control leg. These results showed that eccentric contractions decreased vessel diameter, impaired the blood flow response, and promoted hyperalgesia. Thus, the results suggest that the blood flow reduction may be involved in the increased pain response after eccentric exercise.


Asunto(s)
Ejercicio Físico , Contracción Muscular , Músculo Esquelético/irrigación sanguínea , Mialgia/fisiopatología , Adulto , Femenino , Humanos , Masculino , Umbral del Dolor , Factores de Tiempo
2.
Lett Appl Microbiol ; 67(3): 235-243, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29856469

RESUMEN

Streptococcus agalactiae is among the most relevant aetiologic agent of bovine clinical and subclinical mastitis, a major problem for the dairy industry. In Brazil, clonal diversity, capsular typing and multidrug resistance profiles of S. agalactiae related to human and bovine infections need further investigation. Presently, S. agalactiae isolates of bovine subclinical mastitis, from Brazilian Northeastern region, were submitted to capsular and pulsed-field gel electrophoresis (PFGE)-typing, antimicrobial susceptibility and assays of biofilm formation at different time incubation and pH levels. Sixteen bovine isolates were characterized by polymerase chain reaction assay as S. agalactiae capsular type II (CTII) and classified by PFGE in A1/A2 (n = 06), B1/B2 (n = 06), C (n = 03) and D (n = 01) patterns. Bovine S. agalactiae CTII strains were classified as 25% multidrug-resistant (MDR) with susceptibility to penicillin, linezolid and vancomycin. Biofilm formation on abiotic surface was strain- and time-dependent with significantly higher rates at pH 6·5. In conclusion, S. agalactiae capsular type II isolates recovered from bovine subclinical mastitis produced different pH-dependent biofilm levels. Our findings suggest that biofilm production is modulated by environmental factors and provides S. agalactiae advantageous in colonizing mammary gland during mastitis development, including MDR strains. SIGNIFICANCE AND IMPACT OF THE STUDY: Streptococcus agalactiae is among the most relevant aetiologic agent of bovine clinical and subclinical mastitis, a major problem for the dairy industry. The disease may cause significant economic loss due to decreased production and milk quality and increased use of medicaments. Presently, data demonstrated that biofilm formation favours the establishment of infectious process in health mammary tissue by S. agalactiae and emphasizes that an acidic pH promotes adhesion by biofilm-forming bacterial strains. S. agalactiae strains (25%) showed resistance to tetracycline, azithromycin, erythromycin and clindamycin, and consequently were classified as multidrug-resistant strains.


Asunto(s)
Biopelículas , Mastitis Bovina/microbiología , Leche/microbiología , Streptococcus agalactiae/fisiología , Animales , Antibacterianos/farmacología , Biopelículas/efectos de los fármacos , Brasil , Bovinos , Farmacorresistencia Bacteriana Múltiple , Femenino , Leche/química , Streptococcus agalactiae/efectos de los fármacos , Streptococcus agalactiae/genética , Streptococcus agalactiae/aislamiento & purificación
3.
Genes Immun ; 17(1): 13-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26492519

RESUMEN

Type 1 diabetes (T1D) is a multifactorial disease that has a strong genetic component. The HLA-G is a nonclassical HLA class I locus that is associated with immunomodulatory functions, including downregulation of innate and adaptive immune responses and induction of immune tolerance. However, there is currently limited information about the involvement of HLA-G in T1D susceptibility. This case-control study aims to investigate the T1D susceptibility association of alleles and genotypes of a widely investigated 14-bp insertion/deletion polymorphism in the HLA-G and to provide further evidence of the frequency distribution of class II HLA-DR-DQ-risk genotypes in T1D children and adolescents in the Brazilian population. The deletion allele and the homozygous deletion genotype are associated with susceptibility to T1D and the insertion allele and the heterozygous deletion/insertion genotype are associated with protection from T1D. We also confirm that genetic susceptibility to T1D is associated with the DRB1*03:01-DQA1*05:01-DQB1*02:01 and DRB1*04-DQA1*03:01-DQB1*03:02 haplotypes in Brazilian northeast region. The DR3-DQ2/DR4-DQ8 genotype conferred the highest detected risk for T1D. Our results identify a novel association of the 14-bp deletion allele and the homozygous deletion genotype with T1D development and provide additional evidence of the importance of HLA class II heterozygous DR3-DQ2/DR4-DQ8 genotype in T1D susceptibility.


Asunto(s)
Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/inmunología , Predisposición Genética a la Enfermedad , Antígenos HLA-G/genética , Adolescente , Brasil , Estudios de Casos y Controles , Niño , Femenino , Antígenos HLA-D/genética , Antígenos HLA-D/inmunología , Antígenos HLA-G/inmunología , Haplotipos , Humanos , Masculino , Polimorfismo Genético
4.
Scand J Med Sci Sports ; 26(8): 967-74, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26247618

RESUMEN

The criterion of long-standing groin pain diagnoses in athletes usually relies on palpation and clinical tests. An experimental pain model was developed to examine the clinical tests under standardized conditions. Pain was induced by hypertonic saline injected into the proximal adductor longus (AL) tendon or rectus femoris (RF) tendon in 15 healthy male participants. Isotonic saline was injected contralaterally as a control. Pain intensity was assessed on a visual analog scale (VAS). Resisted hip adduction at three different angles and trunk flexion were completed before, during, and after injections. Pain provocation in the presence of experimental pain was recorded as a true positive compared with pain provocation in the non-pain conditions. Similar peak VAS scores were found after hypertonic saline injections into the AL and RF and both induced higher VAS scores than isotonic saline (P < 0.01). Adduction at 0° had the greatest positive likelihood ratio (+LR = 2.8, 95%CI: 1.09-7.32) with 45° (-LR = 0.0, 95%CI: 0.00-1.90) and 90° (-LR = 0.0, 95%CI: 0.00-0.94) having the lowest negative LR. This study indicates that the 0° hip adduction test resisted at the ankles optimizes the diagnostic procedure without compromising diagnostic capacity to identify experimental groin pain. Validation in clinical populations is warranted.


Asunto(s)
Ingle , Dolor Musculoesquelético/fisiopatología , Examen Físico/métodos , Tendones/fisiopatología , Adulto , Cadera , Humanos , Soluciones Isotónicas/farmacología , Funciones de Verosimilitud , Masculino , Contracción Muscular , Dolor Musculoesquelético/diagnóstico , Dolor Musculoesquelético/etiología , Dimensión del Dolor , Posicionamiento del Paciente , Curva ROC , Solución Salina Hipertónica/farmacología , Tendones/efectos de los fármacos , Adulto Joven
5.
Epidemiol Infect ; 143(4): 791-8, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25703400

RESUMEN

We describe microbiological, clinical and epidemiological aspects of a diphtheria outbreak that occurred in Maranhão, Brazil. The majority of the 27 confirmed cases occurred in partially (n = 16) or completely (n = 10) immunized children (n = 26). Clinical signs and characteristic symptoms of diphtheria such as cervical lymphadenopathy and pseudomembrane formation were absent in 48% and 7% of the cases, respectively. Complications such as paralysis of lower limbs were observed. Three cases resulted in death, two of them in completely immunized children. Microbiological analysis identified the isolates as Corynebacterium diphtheriae biovar intermedius with a predominant PFGE type. Most of them were toxigenic and some showed a decrease in penicillin G susceptibility. In conclusion, diphtheria remains endemic in Brazil. Health professionals need to be aware of the possibility of atypical cases of C. diphtheriae infection, including pharyngitis without pseudomembrane formation.


Asunto(s)
Difteria/epidemiología , Brotes de Enfermedades , Adolescente , Adulto , Brasil/epidemiología , Niño , Corynebacterium diphtheriae/efectos de los fármacos , Difteria/tratamiento farmacológico , Difteria/microbiología , Difteria/patología , Farmacorresistencia Bacteriana , Electroforesis en Gel de Campo Pulsado , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Adulto Joven
6.
Oral Dis ; 21(3): 393-9, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25219684

RESUMEN

OBJECTIVES: We investigated the relationship between non-syndromic cleft lip/palate (NSCLP) and polymorphisms in methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR), methionine synthase reductase (MTRR), and RFC1, as well as the corresponding interactions with environmental factors. SUBJECTS AND METHODS: One hundred and forty NSCLP patients and their mothers, as well as 175 control individuals and their mothers, were recruited. Information regarding smoking and alcohol consumption was recorded. Blood samples were obtained in order to measure serum folate and cobalamin, as well as, plasma total homocysteine concentrations and to extract DNA. Polymorphisms in MTHFR(677C>T and 1298A>C), MTR(2756A>G), MTR(66A>G), and RFC1(80A>G) were analyzed by PCR-restriction fragment length polymorphism. RESULTS: Among the patients, 59.5% had cleft lip and palate, 22.0% had cleft palate, and 18.5% had cleft lip only. Maternal alcohol consumption and reduced folic acid concentrations in both children and mothers (P < 0.001 and P = 0.003, respectively) were risk factors for NSCLP. Patients and their mothers carrying the MTHFR 667T allele showed lower serum folate than CC (P = 0.011 and P = 0.030, respectively). Mothers who carried the MTHFR 1298C allele exhibited increased risk of having a child with NSCLP, after adjusting for alcohol consumption (OR: 1.75, 95% CI: 1.03-2.99, P = 0.038). CONCLUSIONS: Reduced folic acid levels, alcohol consumption, and the MTHFR 677T and 1298C alleles may have contributed to NSCLP development in this sample population from Rio Grande do Norte.


Asunto(s)
Consumo de Bebidas Alcohólicas , Encéfalo/anomalías , Labio Leporino/genética , Fisura del Paladar/genética , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Efectos Tardíos de la Exposición Prenatal/genética , 5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa/genética , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Femenino , Ferredoxina-NADP Reductasa/genética , Ácido Fólico/sangre , Interacción Gen-Ambiente , Homocisteína/sangre , Humanos , Masculino , Polimorfismo Genético , Embarazo , Proteína de Replicación C/genética , Adulto Joven
7.
Infection ; 42(5): 835-42, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24934541

RESUMEN

INTRODUCTION: Despite the recent advances in diagnosis and treatment, mortality rates due to infective endocarditis (IE) remain high if not aggressively treated with antibiotics, whether or not associated with surgery. Data on the prevalence, epidemiology and etiology of IE from developing countries remain scarce. The aim of this observational, prospective cohort study was to report a 5-year experience of IE at two teaching hospitals in Rio de Janeiro, Brazil. MATERIAL AND METHODS: Demographical, anamnestic and microbiological characteristics of 71 IE patients were evaluated during the period of January 2009 to March 2013. RESULTS: The mean age of the IE patients was 49.8 ± 2.4 years, of which 41 (57.7%) were males. The median time between the onset of symptoms and diagnosis of IE was 35.8 ± 4.8 days. A total of 31 (43.6%) cases of community-acquired infective endocarditis (CAIE) and 40 (56.3%) cases of healthcare-acquired infective endocarditis (HAIE) were observed. Staphylococcus aureus (30%) was the predominant cause of IE. Streptococcus spp. (45.1 %) was the predominant cause of the CAIE while S. aureus (32.5%) and Enterococcus spp. (27.2 %) were the main etiological agents of HAIE. For 64 (90.1 %) patients with native valve endocarditis, the mitral valve was the most commonly affected (48.3%). The main source of IE in this cohort was intravascular catheter. The tricuspid valve and renal chronic insufficiency were more frequent in patients with HAIE than CAIE (p = 0.001). The risk factors associated with in-hospital mortality rate (46.4%) in IE patients were: age over 45 (OR 3.4; 95% CI 1.03-11.24; p = 0.04) and chronic renal insufficiency (OR 38.3; 95% CI 3.2-449.4; p = 0.004). CONCLUSIONS: At two main teaching hospitals in Brazil, Streptococcus spp. was the principal pathogen of CAIE while S. aureus and Enterococcus spp. were the most frequent causes of HAIE. IE remains a serious disease associated with high in-hospital mortality rate (46.6%); especially, in individuals over 45 years of age and with renal failure. Data suggest that early surgery may improve the outcome of IE patients.


Asunto(s)
Bacterias/aislamiento & purificación , Infecciones Bacterianas/mortalidad , Endocarditis/mortalidad , Mortalidad Hospitalaria , Adulto , Infecciones Bacterianas/microbiología , Brasil/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Infecciones Comunitarias Adquiridas/mortalidad , Infección Hospitalaria/microbiología , Infección Hospitalaria/mortalidad , Endocarditis/microbiología , Femenino , Hospitales de Enseñanza/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo
8.
J Biol Regul Homeost Agents ; 28(3): 449-60, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25316132

RESUMEN

We investigated the relationship of the positivity for Chlamydophila pneumoniae (Cpn) and Mycoplasma pneumonia (Mpn), inflammatory and metabolic markers, and mRNA expression and polymorphisms of the TLR2, TLR4, IL-6 and TNFA genes with acute myocardial infarction (AMI). Two hundred and eighteen individuals (98 AMI and 120 non-AMI) were selected at two Clinical Centers. Blood samples were drawn to extract DNA and RNA and to measure laboratory variables including anti-Cpn IgM and IgG. Cpn and Mpn genomic DNA as well as TLR2, TLR4, IL-6 and TNFA mRNA expression were evaluated by quantitative real-time PCR (qPCR). Gene polymorphisms were detected by PCR-HRM. AMI patients had higher positivity for Cpn-DNA (17.3%) than non-AMI group (6.7%, p=0.018). In addition, Cpn-DNA positivity was an independent predictor of risk for AMI (OR: 2.56, CI: 1.08 - 6.04, p=0.031). Positivity for anti-Cpn IgG and Mpn-DNA was similar between AMI and non-AMI (> 0.05). TLR4 mRNA expression was higher in AMI than non-AMI individuals (p=0.005). CD14 -260C> T, TNFA -308A> G, TLR2 c.2258G> A, TLR4 c.896A> G and TLR4 c.1196> T variants were not associated with increased risk for AMI (p> 0.05). In the AMI group, individuals carrying CD14 -260CC genotype had higher hsCRP levels than CT/TT carriers (p=0.041). These results are suggestive that Cpn-DNA positivity and increased TLR4 mRNA expression in blood leukocytes may be associated with AMI and could be useful markers to evaluate the severity and progression of the atherosclerotic disease in AMI patients.


Asunto(s)
Neumonía por Clamidia/metabolismo , Chlamydophila pneumoniae , Regulación de la Expresión Génica , Leucocitos/metabolismo , Infarto del Miocardio , Receptor Toll-Like 4/biosíntesis , Anciano , Neumonía por Clamidia/complicaciones , Humanos , Interleucina-6/biosíntesis , Masculino , Persona de Mediana Edad , Mycoplasma pneumoniae , Infarto del Miocardio/complicaciones , Infarto del Miocardio/metabolismo , Neumonía por Mycoplasma/complicaciones , Neumonía por Mycoplasma/metabolismo , ARN Mensajero/biosíntesis , Factores de Riesgo , Receptor Toll-Like 2/biosíntesis , Factor de Necrosis Tumoral alfa/biosíntesis
9.
Environ Monit Assess ; 186(5): 2979-99, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24590229

RESUMEN

The Toluca Valley is located on the high plains of Mexico, where there are significant industrial zones and large populations. Water needs are almost exclusively met by groundwater, which has brought about intense exploitation of the aquifer and indication of some contamination. The present study investigates the effect of urbanization, related to industrialization of the region, on groundwater in the central portion of the Toluca Valley aquifer--a zone with high population density and where the largest industrial park is located. A general decline in the groundwater level has been found over the years, at a rate of as much as 2.5 m/year. The appearance of a large drawdown cone was identified, indicating changes in the direction of groundwater flow. Also identified was the presence of several ground fissures, the location of which coincided with the drawdown cone. In hydrochemical terms, the water type is sodium-magnesium bicarbonate and this characteristic has not changed over time, although it has been possible to detect the presence of larger quantities of sulfates (up to 117 mg/L) and nitrates (up to 47 mg/L) in recent years, likely associated with contamination from industrial and urban wastewater. Factor analysis made it possible to identify ions that would characterize natural processes involving the acquisition of salts (HCO3 (-), Na(+), Mg(2+), and Si), as well as anthropic activities (SO4 (2-), NO3 (-), Cl(-), Ca(2+), and K(+)).


Asunto(s)
Monitoreo del Ambiente , Agua Subterránea/química , Hidrodinámica , Urbanización , Contaminantes Químicos del Agua/análisis , México , Nitratos/análisis , Sales (Química)/análisis , Sulfatos/análisis
10.
Oral Dis ; 19(5): 507-12, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23130753

RESUMEN

OBJECTIVE: The aim of this study was to investigate the contribution of 6 polymorphic variants of the MSX1 gene in non-syndromic cleft lip and/or palate (NSCL/P). METHODS: Three hundred and fifty-eight individuals (158 NSCL/P cases and 200 controls) were genotyped by TaqMan allelic discrimination using predesigned SNP assays. Statistical analyses were conducted using the software spss 15.0 and the r statistical suite. Haplotype block structure and haplotype frequencies were determined using the Haploview. A P-value of 0.05 and confidence interval of 95% were used for all of statistical tests. RESULTS: The patients with non-syndromic cleft lip and/or palate were characterized by similar distribution of MSX1 genotypes and allele in comparison to subjects without oral clefts (P > 0.05). Two haplotype blocks were constructed with polymorphisms of MSX1 gene and haplotypes formed showed a similar frequency in patients with and without oral clefts. CONCLUSIONS: The present study provides no evidence that MSX1 polymorphisms (rs3775261, rs1042484, rs12532, rs6446693, rs4464513 and rs1907998) play a major role in NSCL/P.


Asunto(s)
Labio Leporino/genética , Fisura del Paladar/genética , Factor de Transcripción MSX1/genética , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Femenino , Humanos , Masculino
11.
Nat Genet ; 18(4): 325-30, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9537413

RESUMEN

Stable transduction of mammalian cells typically involves random integration of viral vectors by non-homologous recombination. Here we report that vectors based on adeno-associated virus (AAV) can efficiently modify homologous human chromosomal target sequences. Both integrated neomycin phosphotransferase genes and the hypoxanthine phosphoribosyltransferase gene were targeted by AAV vectors. Site-specific genetic modifications could be introduced into approximately 1% of cells, with the highest targeting rates occurring in normal human fibroblasts. These results suggest that AAV vectors could be used to introduce specific genetic changes into the genomic DNA of a wide variety of mammalian cells, including therapeutic gene targeting applications.


Asunto(s)
Adenoviridae/genética , Marcación de Gen , Vectores Genéticos/genética , Relación Dosis-Respuesta a Droga , Técnicas de Transferencia de Gen , Genes/genética , Genes Virales/genética , Vectores Genéticos/farmacología , Humanos , Hipoxantina Fosforribosiltransferasa/genética , Masculino , Mutación/genética , Neomicina , Fosfotransferasas (Aceptor de Grupo Alcohol)/genética , Proteínas Recombinantes/genética , Recombinación Genética/efectos de los fármacos , Transfección/genética , Transfección/métodos , Células Tumorales Cultivadas
12.
Oper Dent ; 48(1): 51-58, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36534034

RESUMEN

PURPOSE: To evaluate the effect of short curing time using a high-radiant emittance light on polymerization shrinkage vectors in different consistency bulk-fill composites (BFRCs) using micro-computed tomography. METHODS AND MATERIALS: Radiopaque zirconia fillers were homogeneously incorporated and functioned as radiopaque tracers into two regular-paste: TBFill (Tetric EvoCeram Bulk Fill) and TPFill (Tetric PowerFill), and two flowable (n=6): TBFlow (Tetric EvoFlow Bulk Fill) and TPFlow (Tetric PowerFlow) resin composites. Class I cavities (4 mm depth × 4 mm length × 4 mm width) were 3D-printed and filled in a single increment: TBFill and TBFlow were light-activated using a Bluephase Style 20i (10 seconds in high-mode); TPFill and TPFlow were light-activated using a Bluephase PowerCure (three seconds). The same adhesive system (Adhese Universal) was used for all groups. Microcomputed tomography scans were obtained before and after light-activation. Filler particle movement was identified by polymerization shrinkage vectors at five depths (from 0-4 mm): top, top-middle, middle, middle-bottom and bottom. RESULTS: TPFlow showed the lowest total vector displacement, followed by TBFlow, TBFill and TPFill, significantly different among each other (p<0.05). Generally, BFRCs showed decreased vector displacement with increased depth, and higher displacement at the top-surface (p<0.05). Qualitative analysis showed a similar pattern of vector magnitude and displacement for groups TBFill and TPFill, with displacement vectors on occlusal (top) surfaces toward the center of the restoration from the top to middle areas, and relatively limited displacement at the bottom. TBFlow and TPFlow showed more displacement on the occlusal (top). CONCLUSIONS: Short curing time with high-radiant emittance on fast-curing BFRCs was shown to be a feasible option in terms of vector displacement. Flowable BFRCs presented lower vector displacement than their regular-viscosity versions.


Asunto(s)
Resinas Compuestas , Caries Dental , Humanos , Microtomografía por Rayos X , Polimerizacion , Ensayo de Materiales , Curación por Luz de Adhesivos Dentales
13.
Epidemiol Infect ; 140(4): 617-20, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21669023

RESUMEN

Invasive infections caused by Corynebacterium diphtheriae in vaccinated and non-vaccinated individuals have been reported increasingly. In this study we used multilocus sequence typing (MLST) to study genetic relationships between six invasive strains of this bacterium isolated solely in the urban area of Rio de Janeiro, Brazil, during a 10-year period. Of note, all the strains rendered negative results in PCR reactions for the tox gene, and four strains presented an atypical sucrose-fermenting ability. Five strains represented new sequence types. MLST results did not support the hypothesis that invasive (sucrose-positive) strains of C. diphtheriae are part of a single clonal complex. Instead, one of the main findings of the study was that such strains can be normally found in clonal complexes with strains related to non-invasive disease. Comparative analyses with C. diphtheriae isolated in different countries provided further information on the geographical circulation of some sequence types.


Asunto(s)
Corynebacterium diphtheriae/genética , Difteria/microbiología , Adolescente , Adulto , Anciano , Técnicas de Tipificación Bacteriana , Brasil/epidemiología , Niño , Difteria/epidemiología , Femenino , Humanos , Masculino , Tipificación de Secuencias Multilocus
14.
J Clin Pharm Ther ; 37(3): 356-63, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21883330

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Fluconazole is an antifungal agent that is commonly used to treat patients with serious systemic fungal infections in intensive care units. Fosfluconazole is a phosphate prodrug of fluconazole, which was developed to reduce the volume of fluid required to administer fluconazole by intravenous injection. The objective of this study was to characterize the pharmacokinetics of the antifungal fluconazole after the intravenous administration of the prodrug fosfluconazole or fluconazole in critically ill patients with serious systemic fungal infections, by population pharmacokinetic analysis using the nonmem software package. METHODS: Clinical biochemical data including serum fluconazole levels were obtained from 57 patients treated in the intensive care unit along with two naïve pooled patients gleaned from previous reports. The pharmacokinetic model of fluconazole was estimated using a one-compartment model. The probability that the area under the concentration-time curve is higher than 800 µg h/mL was determined by simulation. RESULTS: It was assumed that all the administered fosfluconazole was converted to fluconazole with an estimated fosfluconazole-fluconazole conversion rate constant of 2·05/h. The significant covariates for clearance for fluconazole (CL) and volume of distribution for fluconazole (Vd) were resulted in creatinine clearance (CLcr) and body weight (BW), respectively, in the final pharmacokinetic model equations: CL (L/h) = 0·799 × [CLcr (mL/min)/92·7](0·685) and Vd (L) = 48·1 × [BW (kg)/65](1·40) , where the interpatient variabilities in CL and Vd and the intrapatient variability were 44·8%, 79·7% and 19·8%, respectively. On the basis of the results of the Monte Carlo simulation, the probabilities of target attainment were 60%, 26% and 11% for 400 mg/day administration as fluconazole equivalent at CLcr values of 40, 70 and 100 mL/min, respectively. WHAT IS NEW AND CONCLUSION: The present population pharmacokinetic analysis strongly indicates that fosfluconazole (and fluconazole) dosage should be optimized in terms of CLcr in critically ill patients.


Asunto(s)
Antifúngicos/farmacocinética , Fluconazol/análogos & derivados , Fluconazol/farmacocinética , Micosis/tratamiento farmacológico , Organofosfatos/uso terapéutico , Profármacos/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antifúngicos/administración & dosificación , Antifúngicos/sangre , Antifúngicos/uso terapéutico , Simulación por Computador , Cuidados Críticos , Femenino , Fluconazol/administración & dosificación , Fluconazol/sangre , Fluconazol/uso terapéutico , Semivida , Humanos , Inyecciones Intravenosas , Japón , Tasa de Depuración Metabólica , Persona de Mediana Edad , Modelos Biológicos , Método de Montecarlo , Micosis/sangre , Micosis/metabolismo , Organofosfatos/administración & dosificación , Profármacos/administración & dosificación , Adulto Joven
15.
Oper Dent ; 47(1): 55-63, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-35584286

RESUMEN

OBJECTIVES: To evaluate the effect of argon plasma treatment (PLA) when combined with sandblasting (SAN), silanization (SIL), and hydrophobic bonding resin (HBR) on the shear bond strength (SBS) of a two-year water-aged resin composite bonded to a newly placed composite after 24 hours and one year of water-storage. METHODS AND MATERIALS: Thirty-six light-cured composite plates (20mm x 20mm x 4mm thick) were obtained and stored at 37°C in distilled water for 2 years. These aged plates were distributed into 6 groups (n=6) according to the surface treatment: no treatment (Negative Control); SAN+SIL+HBR (Positive Control); SAN+PLA+SIL+HBR; PLA+ SIL+HBR; PLA+SIL; PLA+HBR. Fresh resin composite cylinders were built up using silicone molds (hole: 1.5 mm high x 1.5 mm diameter) positioned over the aged plates. Half of the SBS samples were stored in distilled water for 24 hours and loaded until failure, while the other half were stored for 1 year before being tested. Data were submitted to two-way analysis of variance and post-hoc Tukey Test (preset alpha of 0.05). RESULTS: Positive Control, SAN+PLA+SIL+HBR and PLA+SIL+HBR groups presented higher SBS means at the 24 hour evaluation. After 1 year of water storage, all groups demonstrated significant SBS reduction, with the SAN+PLA+SIL+HBR group presenting the highest SBS. CONCLUSIONS: Resin plasma treatment in combination with other surface treatments can improve the SBS of composite repairs after one year of water storage. The SBS of the composite repair was not stable over time regardless of the surface treatment.


Asunto(s)
Recubrimiento Dental Adhesivo , Gases em Plasma , Argón , Resinas Compuestas/química , Resinas Compuestas/uso terapéutico , Ensayo de Materiales , Gases em Plasma/uso terapéutico , Poliésteres , Cementos de Resina/química , Resistencia al Corte , Propiedades de Superficie , Agua/química
16.
Antonie Van Leeuwenhoek ; 99(3): 733-7, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20941542

RESUMEN

During the last decades, the majority of Brazilian Corynebacterium diphtheriae isolates were shown to be capable to metabolize sucrose, sometimes leading to erroneous identification as a non-diphtheric Corynebacterium species. The sequencing of the polymorphic region of the RNA polymerase beta subunit-encoding gene (rpoB) is an important taxonomic tool for identification of corynebacteria. The present study aimed to investigate the rpoB gene polymorphic features of sucrose-fermenting and non sucrose-fermenting strains. The results showed that sucrose-fermenting strains presented rpoB gene polymorphic regions with more than 98% similarity with the sequences deposited in the gene bank corresponding to non sucrose-fermenting strains. Data indicate that sucrose-fermenting isolates may act as a variant of C. diphtheriae biotype mitis. In addition we alert that sucrose-fermenting strains should not be discarded as contaminants mainly in countries where the possibility of isolation of this variant is higher.


Asunto(s)
Proteínas Bacterianas/metabolismo , Corynebacterium diphtheriae/genética , Corynebacterium diphtheriae/metabolismo , Sacarosa/metabolismo , Proteínas Bacterianas/clasificación , Proteínas Bacterianas/genética , Fermentación , Filogenia
17.
Genet Mol Res ; 10(2): 1290-4, 2011 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-21732292

RESUMEN

Despite the existence of a vaccine against diphtheria, this disease remains endemic and is reemerging in several regions due to many factors, including variations in genes coding for virulence factors. One common feature of virulence factors is their high concentration in pathogenicity islands (PAIs), very unstable regions acquired via horizontal gene transfer, which has lead to the emergence of various bacterial pathogens. The 13 putative PAIs in Corynebacterium diphtheriae NCTC 13129 and the reemergence of this disease point to the great variability in the PAIs of this species, which may reflect on bacterial life style and physiological versatility. We investigated the relationships between the large number of PAIs in C. diphtheriae and the possible implications of their plasticity in virulence. The GenoFrag software was used to design primers to analyze the genome plasticity of two pathogenicity islands of the reference strain (PiCds 3 and 8) in 11 different strains. We found that PiCd 3 was absent in only two strains, showing genes playing putative important roles in virulence and that only one strain harbored PiCd 8, due to its location in a putative "hotspot" for horizontal gene transfer events.


Asunto(s)
Corynebacterium diphtheriae/patogenicidad , Reacción en Cadena de la Polimerasa/métodos , Virulencia/genética , Secuencia de Bases , Corynebacterium diphtheriae/genética , Cartilla de ADN , Genes Bacterianos
18.
Gene Ther ; 17(3): 380-8, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19907502

RESUMEN

Several gene therapy applications require the transfer and simultaneous expression of multiple genes in the same cell. In this study, we analyzed the potential for coordinated expression of an endogenous bidirectional promoter located on chromosome X, which controls the expression of the heterogeneous nuclear ribonucleoprotein H2 (HNRNPH2) and alpha-galactosidase (GLA) genes. The promoter was cloned in both transcriptional orientations in a foamy virus (FV) vector backbone, whereas the enhanced green fluorescent protein (EGFP) and low-affinity nerve growth factor receptor (DeltaLNGFR) reporter genes were cloned in the 5'-3' and 3'-5' transcriptional orientations, respectively. In all the cell lines tested, both vectors showed high levels of transgene coexpression that reached 76% of total positive cells (range from 76 to 18%). Comparison of EGFP and DeltaNGFR levels revealed that the side of the promoter that drives the expression of the HNRNPH2 gene in the genome was stronger and in accordance to its in situ activity. When tested with CD34(+) cells, transgene coexpression reached 35.3% of all positive cells in progenitor assays and 16.8% of all positive cells after transplantation in NOD/severe combined immunodeficient mice. In summary, we show that the endogenous promoter used in this study holds bidirectional activity in the context of FV vectors and can be used in gene therapy applications requiring synchronized expression of two genes.


Asunto(s)
Terapia Genética/métodos , Vectores Genéticos/genética , Ribonucleoproteína Heterogénea-Nuclear Grupo F-H/genética , Spumavirus/genética , Transgenes , alfa-Galactosidasa/genética , Animales , Antígenos CD34/análisis , Cromosomas Humanos X/genética , Expresión Génica , Humanos , Ratones , Ratones Endogámicos NOD , Ratones SCID , Monocitos , Regiones Promotoras Genéticas
19.
Oper Dent ; 45(4): E167-E175, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32216725

RESUMEN

CLINICAL RELEVANCE: Secondary caries are the main reason for the failure of restorations, class II being the most affected. Techniques that promote less gap percentage are important. Flowable bulk fill composites used at such locations have been shown to decrease gap formation while being a faster procedure than an incremental technique.


Asunto(s)
Caries Dental , Restauración Dental Permanente , Resinas Compuestas , Adaptación Marginal Dental , Humanos , Microtomografía por Rayos X
20.
Oper Dent ; 45(5): 496-505, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32101499

RESUMEN

CLINICAL RELEVANCE: Shortened light curing does not affect volumetric polymerization shrinkage or cohesive tensile strength but negatively affects the shear bond strength of some bulk-fill resin composites. When performing shortened light curing, clinicians should be aware of the light output of their light-curing units. SUMMARY: Purpose: To evaluate volumetric polymerization shrinkage (VPS), shear bond strength (SBS) to dentin, and cohesive tensile strength (CTS) of bulk-fill resin composites (BFRCs) light activated by different modes.Methods and Materials: Six groups were evaluated: Tetric EvoCeram bulk fill + high mode (10 seconds; TEC H10), Tetric EvoFlow bulk fill + high mode (TEF H10), experimental bulk fill + high mode (TEE H10), Tetric EvoCeram bulk fill + turbo mode (five seconds; TEC T5), Tetric EvoFlow bulk fill + turbo mode (TEF T5), and experimental bulk fill + turbo mode (TEE T5). Bluephase Style 20i and Adhese Universal Vivapen were used for all groups. All BFRC samples were built up on human molar bur-prepared occlusal cavities. VPS% and location were evaluated through micro-computed tomography. SBS and CTS tests were performed 24 hours after storage or after 5000 thermal cycles; fracture mode was analyzed for SBS.Results: Both TEC H10 and TEE H10 presented lower VPS% than TEF H10. However, no significant differences were observed with the turbo-curing mode. No differences were observed for the same BFRC within curing modes. Occlusal shrinkage was mostly observed. Regarding SBS, thermal cycling (TC) affected all groups. Without TC, all groups showed higher SBS values for high mode than turbo mode, while with TC, only TEC showed decreased SBS from high mode to turbo modes; modes of fracture were predominantly adhesive. For CTS, TC affected all groups except TEE H10. In general, no differences were observed between groups when comparing the curing modes.Conclusions: Increased light output with a shortened curing time did not jeopardize the VPS and SBS properties of the BFRCs, although a decreased SBS was observed in some groups. TEE generally showed similar or improved values for the tested properties in a shortened light-curing time. The VPS was mostly affected by the materials tested, whereas the SBS was affected by the materials, curing modes, and TC. The CTS was not affected by the curing modes.


Asunto(s)
Resinas Compuestas , Luces de Curación Dental , Humanos , Curación por Luz de Adhesivos Dentales , Ensayo de Materiales , Diente Molar , Polimerizacion , Resistencia al Corte , Microtomografía por Rayos X
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