Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
JAMA Netw Open ; 3(7): e2011444, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32706382

RESUMEN

Importance: Several studies have reported that the progression of coronary atherosclerosis, as measured by serial coronary computed tomographic (CT) angiography, is associated with the risk of future cardiovascular events. However, the cumulative consequences of multiple risk factors for plaque progression and the development of adverse plaque characteristics have not been well characterized. Objectives: To examine the association of cardiovascular risk factor burden, as assessed by atherosclerotic cardiovascular disease (ASCVD) risk score, with the progression of coronary atherosclerosis and the development of adverse plaque characteristics. Design, Setting, and Participants: This cohort study is a subgroup analysis of participant data from the prospective observational Progression of Atherosclerotic Plaque Determined by Computed Tomographic Angiography Imaging (PARADIGM) study, which evaluated the association between serial coronary CT angiography findings and clinical presentation. The PARADIGM international multicenter registry, which includes 13 centers in 7 countries (Brazil, Canada, Germany, Italy, Portugal, South Korea, and the US), was used to identify 1005 adult patients without known coronary artery disease who underwent serial coronary CT angiography scans (median interscan interval, 3.3 years; interquartile range [IQR], 2.6-4.8 years) between December 24, 2003, and December 16, 2015. Based on the 10-year ASCVD risk score, the cardiovascular risk factor burden was classified as low (<7.5%), intermediate (7.5%-20.0%), or high (>20.0%). Data were analyzed from February 8, 2019, to April 17, 2020. Exposures: Association of baseline ASCVD risk burden with plaque progression. Main Outcomes and Measures: Noncalcified plaque, calcified plaque, and total plaque volumes (mm3) were measured. Noncalcified plaque was subclassified using predefined Hounsfield unit thresholds for fibrous, fibrofatty, and low-attenuation plaque. The percent atheroma volume (PAV) was defined as plaque volume divided by vessel volume. Adverse plaque characteristics were defined as the presence of positive remodeling, low-attenuation plaque, or spotty calcification. Results: In total, 1005 patients (mean [SD] age, 60 [8] years; 575 men [57.2%]) were included in the analysis. Of those, 463 patients (46.1%) had a low 10-year ASCVD risk score (low-risk group), 373 patients (37.1%) had an intermediate ASCVD risk score (intermediate-risk group), and 169 patients (16.8%) had a high ASCVD risk score (high-risk group). The annualized progression rate of PAV for total plaque, calcified plaque, and noncalcified plaque was associated with increasing ASCVD risk (r = 0.26 for total plaque, r = 0.23 for calcified plaque, and r = 0.11 for noncalcified plaque; P < .001). The annualized PAV progression of total plaque, calcified plaque, and noncalcified plaque was significantly greater in the high-risk group compared with the low-risk and intermediate-risk groups (for total plaque, 0.99% vs 0.45% and 0.58%, respectively; P < .001; for calcified plaque, 0.61% vs 0.23% and 0.36%; P < .001; and for noncalcified plaque, 0.38%vs 0.22% and 0.23%; P = .01). When further subclassified by noncalcified plaque type, the annualized PAV progression of fibrofatty and low-attenuation plaque was greater in the high-risk group (0.09% and 0.02%, respectively) compared with the low- to intermediate-risk group (n = 836; 0.02% [P = .02] and 0.001% [P = .008], respectively). The interval development of adverse plaque characteristics was greater in the high-risk group compared with the low-risk and intermediate-risk groups (for new positive remodeling, 73 patients [43.2%] vs 151 patients [32.6%] and 133 patients [35.7%], respectively; P = .02; for new low-attenuation plaque, 26 patients [15.4%] vs 44 patients [9.5%] and 35 patients [9.4%]; P = .02; and for new spotty calcification, 37 patients [21.9%] vs 52 patients [11.2%] and 54 patients [14.5%]; P = .002). The progression of noncalcified plaque subclasses and the interval development of adverse plaque characteristics did not significantly differ between the low-risk and intermediate-risk groups. Conclusions and Relevance: Progression of coronary atherosclerosis occurred across all ASCVD risk groups and was associated with an increase in 10-year ASCVD risk. The progression of fibrofatty and low-attenuation plaques and the development of adverse plaque characteristics was greater in patients with a high risk of ASCVD.


Asunto(s)
Enfermedades Cardiovasculares/fisiopatología , Angiografía por Tomografía Computarizada/estadística & datos numéricos , Enfermedad de la Arteria Coronaria/clasificación , Factores de Riesgo , Anciano , Brasil/epidemiología , Enfermedades Cardiovasculares/complicaciones , Enfermedades Cardiovasculares/epidemiología , Estudios de Cohortes , Angiografía por Tomografía Computarizada/métodos , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/epidemiología , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/fisiopatología , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Portugal/epidemiología , Estudios Prospectivos , Quebec/epidemiología , Sistema de Registros/estadística & datos numéricos , República de Corea/epidemiología
2.
Circ Cardiovasc Imaging ; 11(7): e007562, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-30012825

RESUMEN

BACKGROUND: Diagnosis of coronary artery disease and management strategies have relied solely on the presence of diameter stenosis ≥50%. We assessed whether direct quantification of plaque burden (PB) and plaque characteristics assessed by coronary computed tomography angiography could provide additional value in terms of predicting rapid plaque progression. METHODS AND RESULTS: From a 13-center, 7-country prospective observational registry, 1345 patients (60.4±9.4 years old; 57.1% male) who underwent repeated coronary computed tomography angiography >2 years apart were enrolled. For conventional angiographic analysis, the presence of stenosis ≥50%, number of vessel involved, segment involvement score, and the presence of high-risk plaque feature were determined. For quantitative analyses, PB and annual change in PB (△PB/y) in the entire coronary tree were assessed. Clinical outcomes (cardiac death, nonfatal myocardial infarction, and coronary revascularization) were recorded. Rapid progressors, defined as a patient with ≥median value of △PB/y (0.33%/y), were older, more frequently male, and had more clinical risk factors than nonrapid progressors (all P<0.05). After risk adjustment, addition of baseline PB improved prediction of rapid progression to each angiographic assessment of coronary artery disease, and the presence of high-risk plaque further improved the predictive performance (all P<0.001). For prediction of adverse outcomes, adding both baseline PB and △PB/y showed best predictive performance (C statistics, 0.763; P<0.001). CONCLUSIONS: Direct quantification of atherosclerotic PB in addition to conventional angiographic assessment of coronary artery disease might be beneficial for improving risk stratification of coronary artery disease. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02803411.


Asunto(s)
Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Estenosis Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Tomografía Computarizada Multidetector/métodos , Placa Aterosclerótica , Anciano , Brasil , Enfermedad de la Arteria Coronaria/mortalidad , Enfermedad de la Arteria Coronaria/patología , Enfermedad de la Arteria Coronaria/cirugía , Estenosis Coronaria/mortalidad , Estenosis Coronaria/patología , Estenosis Coronaria/cirugía , Vasos Coronarios/patología , Vasos Coronarios/cirugía , Progresión de la Enfermedad , Europa (Continente) , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico por imagen , Revascularización Miocárdica , América del Norte , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Sistema de Registros , República de Corea , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad
3.
JACC Cardiovasc Imaging ; 11(10): 1475-1484, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29909109

RESUMEN

OBJECTIVES: This study sought to describe the impact of statins on individual coronary atherosclerotic plaques. BACKGROUND: Although statins reduce the risk of major adverse cardiovascular events, their long-term effects on coronary atherosclerosis remain unclear. METHODS: We performed a prospective, multinational study consisting of a registry of consecutive patients without history of coronary artery disease who underwent serial coronary computed tomography angiography at an interscan interval of ≥2 years. Atherosclerotic plaques were quantitatively analyzed for percent diameter stenosis (%DS), percent atheroma volume (PAV), plaque composition, and presence of high-risk plaque (HRP), defined by the presence of ≥2 features of low-attenuation plaque, positive arterial remodeling, or spotty calcifications. RESULTS: Among 1,255 patients (60 ± 9 years of age; 57% men), 1,079 coronary artery lesions were evaluated in statin-naive patients (n = 474), and 2,496 coronary artery lesions were evaluated in statin-taking patients (n = 781). Compared with lesions in statin-naive patients, those in statin-taking patients displayed a slower rate of overall PAV progression (1.76 ± 2.40% per year vs. 2.04 ± 2.37% per year, respectively; p = 0.002) but more rapid progression of calcified PAV (1.27 ± 1.54% per year vs. 0.98 ± 1.27% per year, respectively; p < 0.001). Progression of noncalcified PAV and annual incidence of new HRP features were lower in lesions in statin-taking patients (0.49 ± 2.39% per year vs. 1.06 ± 2.42% per year and 0.9% per year vs. 1.6% per year, respectively; all p < 0.001). The rates of progression to >50% DS were not different (1.0% vs. 1.4%, respectively; p > 0.05). Statins were associated with a 21% reduction in annualized total PAV progression above the median and 35% reduction in HRP development. CONCLUSIONS: Statins were associated with slower progression of overall coronary atherosclerosis volume, with increased plaque calcification and reduction of high-risk plaque features. Statins did not affect the progression of percentage of stenosis severity of coronary artery lesions but induced phenotypic plaque transformation. (Progression of AtheRosclerotic PlAque DetermIned by Computed TomoGraphic Angiography Imaging [PARADIGM]; NCT02803411).


Asunto(s)
Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Estenosis Coronaria/tratamiento farmacológico , Vasos Coronarios/efectos de los fármacos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Placa Aterosclerótica , Anciano , Brasil , Angiografía por Tomografía Computarizada , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/patología , Estenosis Coronaria/diagnóstico por imagen , Estenosis Coronaria/patología , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/patología , Progresión de la Enfermedad , Europa (Continente) , Femenino , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Masculino , Persona de Mediana Edad , América del Norte , Estudios Prospectivos , Sistema de Registros , República de Corea , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento , Calcificación Vascular/diagnóstico por imagen , Calcificación Vascular/patología
4.
Electron. j. biotechnol ; Electron. j. biotechnol;16(5): 11-11, Sept. 2013. ilus, tab
Artículo en Inglés | LILACS | ID: lil-690471

RESUMEN

Background: In order to evaluate the variation among different rice types, the genetic diversity in a rice collection composed by 59 breeding lines, 23 landraces, 18 weedy rice lines, and 35 introduced lines that collected from countries worldwide was analyzed using 134 simple sequence repeat markers. Results: In total, 1264 alleles were identified (average, 9.43 per locus). Rare alleles made up a large portion (58.4%) of the detected alleles, and 29 unique alleles associated with rice accessions were also discovered. A model-based structural analysis revealed the presence of three subpopulations. The genetic relationships revealed by the neighbour-joining tree method were fairly consistent with the structure-based membership assignments for most of the accessions. A total of 105 accessions (79.5%) showed a clear relationship to each cluster, while the remaining 27 accessions (20.5%) were categorized as admixtures. Linkage disequilibrium (LD) patterns and distributions are of fundamental importance for genome-wide association mapping. The mean r² value for all intrachromosomal loci pairs was 0.1286. The LD between linked markers decreased with the genetic distance between pairs of linked loci. Conclusions: These results will provide an effective aid for future allele mining, association genetics, mapping and cloning gene(s), germplasm conservation, and improvement programs.


Asunto(s)
Oryza/genética , Variación Genética , Desequilibrio de Ligamiento , Repeticiones de Microsatélite , Alelos , Genética de Población , Genotipo
5.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;45(10): 968-976, Oct. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-647749

RESUMEN

Psychological factors can be correlated with temporomandibular disorders (TMDs), but the mechanisms are unknown. In the present study, we examined the microstructural changes and expression of proinflammatory cytokines in mandibular condylar cartilage of the temporomandibular joint (TMJ) in a psychological stress animal model. Male Sprague-Dawley rats (8 weeks old, 210 ± 10 g) were randomly divided into 3 groups: psychological stress (PS, N = 48), foot shock (FS, N = 24), and control (N = 48). After inducing psychological stress using a communication box with the FS rats for 1, 3, or 5 weeks, PS rats were sacrificed and compared to their matched control littermates, which received no stress and were killed at the same times as the PS rats. Body and adrenal gland weight were measured and corticosterone and adrenocorticotropic hormone levels were determined by radioimmunoassay. After hematoxylin-eosin staining for histological observation, the ultrastructure of the TMJ was examined by scanning electron microscopy. Transcription and protein levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) were evaluated by ELISA and semi-quantitative RT-PCR. The PS group showed a significantly higher adrenal gland weight after 3 weeks of stress and higher hormone levels at weeks 1, 3, and 5. Histopathological changes and thinning cartilage were apparent at weeks 3 and 5. In the PS group, TNF-α increased at 1, 3, and 5 weeks and IL-1β increased significantly after 1 and 3 weeks of stress, and then decreased to normal levels by 5 weeks. Psychological stress increased plasma hormone levels and RT-PCR indicated increased IL-1β and TNF-α expression in the TMJ in a time-dependent manner. These results suggest that cytokine up-regulation was accompanied by stress-induced cartilage degeneration in the mandibular condyle. The proinflammatory cytokines play a potential role in initiating the cartilage destruction that eventually leads to the TMDs.


Asunto(s)
Animales , Masculino , Ratas , Interleucina-1beta/inmunología , Cóndilo Mandibular/inmunología , Cóndilo Mandibular/ultraestructura , Estrés Psicológico/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Cartílago , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Interleucina-1beta/análisis , Microscopía Electrónica de Rastreo , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Necrosis Tumoral alfa/análisis
6.
Braz J Med Biol Res ; 45(10): 968-76, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22714807

RESUMEN

Psychological factors can be correlated with temporomandibular disorders (TMDs), but the mechanisms are unknown. In the present study, we examined the microstructural changes and expression of proinflammatory cytokines in mandibular condylar cartilage of the temporomandibular joint (TMJ) in a psychological stress animal model. Male Sprague-Dawley rats (8 weeks old, 210 ± 10 g) were randomly divided into 3 groups: psychological stress (PS, N = 48), foot shock (FS, N = 24), and control (N = 48). After inducing psychological stress using a communication box with the FS rats for 1, 3, or 5 weeks, PS rats were sacrificed and compared to their matched control littermates, which received no stress and were killed at the same times as the PS rats. Body and adrenal gland weight were measured and corticosterone and adrenocorticotropic hormone levels were determined by radioimmunoassay. After hematoxylin-eosin staining for histological observation, the ultrastructure of the TMJ was examined by scanning electron microscopy. Transcription and protein levels of interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α) were evaluated by ELISA and semi-quantitative RT-PCR. The PS group showed a significantly higher adrenal gland weight after 3 weeks of stress and higher hormone levels at weeks 1, 3, and 5. Histopathological changes and thinning cartilage were apparent at weeks 3 and 5. In the PS group, TNF-α increased at 1, 3, and 5 weeks and IL-1ß increased significantly after 1 and 3 weeks of stress, and then decreased to normal levels by 5 weeks. Psychological stress increased plasma hormone levels and RT-PCR indicated increased IL-1ß and TNF-α expression in the TMJ in a time-dependent manner. These results suggest that cytokine up-regulation was accompanied by stress-induced cartilage degeneration in the mandibular condyle. The proinflammatory cytokines play a potential role in initiating the cartilage destruction that eventually leads to the TMDs.


Asunto(s)
Interleucina-1beta/inmunología , Cóndilo Mandibular/inmunología , Cóndilo Mandibular/ultraestructura , Estrés Psicológico/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Animales , Cartílago , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Interleucina-1beta/análisis , Masculino , Microscopía Electrónica de Rastreo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Necrosis Tumoral alfa/análisis
7.
Electron. j. biotechnol ; Electron. j. biotechnol;15(2): 4-4, Mar. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-640539

RESUMEN

Cymbidium spp. are popular flowering plants. Assessment of the genetic diversity in cultivated Cymbidium facilitates conservation of germplasm and subsequent cultivar improvement. Thus, it is important to develop more efficient polymorphic DNA markers. Although more motifs (403) were identified and more primers (206) were designed in the genomic library compared to the cDNA library, a larger number of successful primers were obtained from the cDNA library (59.9 percent) than from genomic DNA library (51.1 percent). However, higher PIC and gene diversity were identified in genomic SSRs. The average allele number per locus was also higher in genomic SSRs (7.3) than EST-SSRs (5.2), among the 24 evaluated Cymbidium accessions. AT/TA was comparatively high in EST-SSRs, while this motif was not as common in genomic SSRs. The CTT/AAG/TCT/AGA/TTC/GAA and TGC/GCA/GCT/AGC/CTG/CAG motifs were the most abundant tri-nucleotide sequences in EST-SSRs, while GTT/AAC/TGT/ACA/TTG/CAA was the most frequent in genomic SSRs. The number of repeats ranged from 3 to 12 in EST-SSRs. Currently, 52 novel polymorphic SSR markers have been evaluated, which will be useful for germplasm assessments, core set construction, evaluation of genetic diversity, and marker assisted selection (MAS) based Cymbidium breeding.


Asunto(s)
ADN Complementario , Repeticiones de Microsatélite , Orchidaceae/genética , Biblioteca de Genes , Marcadores Genéticos , Variación Genética , Polimorfismo Genético
8.
Electron. j. biotechnol ; Electron. j. biotechnol;15(2): 6-6, Mar. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-640541

RESUMEN

In total, 18 simple sequence repeat (SSR) markers were used to analyze the genetic diversity and population structure of 59 accessions of cultivated strawberry (Fragaria x ananassa Duch.) from Korea, Germany, United States, United Kingdom, and Japan. In total, 101 alleles were detected with an average of 5.6 per locus and 21 specific alleles were identified. Notably, one genotype (Blonoli from Germany) possessed a maximum of 10 different unique alleles specific to each genotype. The gene diversity varied from 0.027 (EMPaEKO1B) to 0.791 (CFACT110), with an average value of 0.509. PIC values ranged from 0.026 to 0.762 (average 0.454). A model-based structure analysis revealed the presence of two populations. The accessions that were clearly assigned to a single population in which > 70 percent of their inferred ancestry was derived from one of the model-based populations. However, two accessions (3.4 percent) in the sample were categorized as having admixed ancestry. Here, we report detailed information on commercially grown strawberry accessions from five different origins using SSR markers. These results couldbe used for broadening the genetic base of commercially grown varieties.


Asunto(s)
Fragaria/genética , Variación Genética , Repeticiones de Microsatélite , Marcadores Genéticos , Genética de Población , Polimorfismo Genético
9.
Extremophiles ; 9(5): 375-83, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15965715

RESUMEN

A new group of anaerobic thermophilic bacteria was isolated from enrichment cultures obtained from deep sea sediments of Peru Margin collected during Leg 201 of the Ocean Drilling Program. A total of ten isolates were obtained from cores of 1-2 m below seafloor (mbsf) incubated at 60 degrees C: three isolates came from the sediment 426 m below sea level with a surface temperature of 9 degrees C (Site 1227), one from 252 m below sea level with a temperature of 12 degrees C (Site 1228), and six isolates under sulfate-reducing condition from the lower slope of the Peru Trench (Site 1230). Strain JW/IW-1228P from the Site 1228 and strain JW/YJL-1230-7/2 from the Site 1230 were chosen as representatives of the two identified clades. Based on the 16S rDNA sequence analysis, these isolates represent a novel group with Thermovenabulum and Caldanaerobacter as their closest relatives. The temperature range for growth was 52-76 degrees C with an optimum at around 68 degrees C for JW/IW-1228P and 43-76 degrees C with an optimum at around 64 degrees C for JW/YJL-1230-7/2. The pH(25C) range for growth was from 6.3 to 9.3 with an optimum at 7.5 for JW/IW-1228P and from 5 to 9.5 with an optimum at 7.9-8.4 for JW/YJL-1230-7/2. The salinity range for growth was from 0% to 6% (w/v) for JW/IW-1228P and from 0% to 4.5% (w/v) for JW/YJL-1230-7/2. The G+C [corrected] mol% of the genomic DNA was 46.3 +/- 0.7% (n = 4) for Thermosediminibacter oceani [corrected] JW/IW-1228PT [corrected] and 45.2 +/- 0.7 (n = 6) for Thermosediminibacter litoriperuensis [corrected] JW/YJL-1230-7/2T [corrected] DNA-DNA hybridization yielded 52% similarity between the two strains. According to 16S rRNA gene sequence analysis, the isolates are located within the family, Thermoanaerobacteriaceae. Based on their morphological and physiological properties and phylogenetic analysis, it is proposed that strain JW/IW-1228P(T) is placed into a novel taxa, Thermosediminibacter oceani, gen. nov., sp. nov. (DSM 16646(T)=ATCC BAA-1034(T)), and JW/YJL-1230-7/2(T) into Thermosediminibacter litoriperuensis sp. nov. (DSM 16647(T) =ATCC BAA-1035(T)).


Asunto(s)
Thermoanaerobacter/clasificación , Thermoanaerobacter/aislamiento & purificación , Anaerobiosis , ADN Bacteriano/genética , Transporte de Electrón , Ácidos Grasos/análisis , Ácidos Grasos/química , Microscopía Electrónica , Perú , Fosfolípidos/química , Fosfolípidos/metabolismo , Filogenia , ARN Ribosómico 16S/genética , Especificidad por Sustrato , Thermoanaerobacter/citología , Thermoanaerobacter/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA