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1.
Reprod Domest Anim ; 53(4): 947-954, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29740884

RESUMEN

Foetal sex determination using polymerase chain reaction (PCR) in mammals is based on the amplification of gender-specific foetal DNA sequences circulating in maternal blood. The bovine synepitheliochorial placenta does not allow a direct contact between the trophoblast and the maternal blood, resulting in difficult passage of foetal DNA and, consequently, its very small amounts in maternal bloodstream. Circulating cell-free foetal DNA (ccffDNA) encompasses short nucleotide fragments (300-600 bp) in maternal circulation. The aim of this study was to assess this non-invasive method in accurate prenatal sexing in early and late gestational periods in comparison with ultrasound diagnostics. As various DNA isolation and amplification methods were tested, their success in obtaining reliable results was evaluated. Two groups were tested, each consisting of 20 pregnant cows. Blood of a bull and a non-pregnant heifer was the controls. Extraction of foetal DNA was accomplished by three different methods: using tubes with silicone membranes, a single-tube extraction without silicone membranes and phenol-chloroform extraction. Following each extraction method, foetal DNA was amplified using PCR and real-time PCR with both bAML and TSPY primers in a separate reaction. Positive results were obtained only after amplification of foetal DNA extracted with a single-tube extraction kit. In comparison with ultrasound examination results and foetal gender recorded at birth, the sensitivity of the PCR test was 90% in Group I, but the technique failed to detect male foetuses in Group II. The real-time PCR test sensitivity in Group I was 90% and in Group II 91.6%.


Asunto(s)
ADN/genética , Reacción en Cadena de la Polimerasa/veterinaria , Análisis para Determinación del Sexo/veterinaria , Animales , Bovinos , Femenino , Masculino , Reacción en Cadena de la Polimerasa/métodos , Embarazo , Reproducción , Ultrasonografía Prenatal/veterinaria
2.
Opt Express ; 25(9): 10090-10102, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28468384

RESUMEN

The self-structuring of laser light in an artificial optical medium composed of a colloidal suspension of nanoparticles is demonstrated using variational and numerical methods extended to dissipative systems. In such engineered materials, competing nonlinear susceptibilities are enhanced by the light induced migration of nanoparticles. The compensation of diffraction by competing focusing and defocusing nonlinearities, together with a balance between loss and gain, allow for self-organization of light and the formation of stable dissipative breathing vortex solitons. Due to their robustness, the breathers may be used for selective dynamic photonic tweezing of nanoparticles in colloidal nanosuspensions.

3.
Vasa ; 40(6): 474-81, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22090181

RESUMEN

BACKGROUND: To evaluate safety, short and long-term graft patency, clinical success rates, and factors associated with patency, limb salvage and mortality after surgical reconstruction in patients younger than 50 years of age who had undergone unilateral iliac artery bypass surgery. PATIENTS AND METHODS: From January 2000 to January 2010, 65 consecutive reconstructive vascular operations were performed in 22 women and 43 men of age < 50 years with unilateral iliac atherosclerotic lesions and claudication or chronic limb ischemia. All patients were followed at 1, 3, 6, and 12 months after surgery and every 6 months thereafter. RESULTS: There was in-hospital vascular graft thrombosis in four (6.1 %) patients. No in-hospital deaths occurred. Median follow-up was 49.6 ± 33 months. Primary patency rates at 1-, 3-, 5-, and 10-year were 92.2 %, 85.6 %, 73.6 %, and 56.5 %, respectively. Seven patients passed away during follow-up of which four patients due to coronary artery disease, two patients due to cerebrovascular disease and one patient due to malignancy. Limb salvage rate after 1-, 3-, 5-, and 10-year follow-up was 100 %, 100 %, 96.3 %, and 91.2 %, respectively. Cox regression analysis including age, sex, risk factors for vascular disease, indication for treatment, preoperative ABI, lesion length, graft diameter and type of pre-procedural lesion (stenosis/occlusion), showed that only age (beta - 0.281, expected beta 0.755, p = 0.007) and presence of diabetes mellitus during index surgery (beta - 1.292, expected beta 0.275, p = 0.026) were found to be significant predictors of diminishing graft patency during the follow-up. Presence of diabetes mellitus during index surgery (beta - 1.246, expected beta 0.291, p = 0.034) was the only variable predicting mortality. CONCLUSIONS: Surgical treatment for unilateral iliac lesions in patients with premature atherosclerosis is a safe procedure with a low operative risk and acceptable long-term results. Diabetes mellitus and age at index surgery are predictive for low graft patency. Presence of diabetes is associated with decreased long-term survival.


Asunto(s)
Arteriopatías Oclusivas/cirugía , Aterosclerosis/cirugía , Implantación de Prótesis Vascular , Oclusión de Injerto Vascular/etiología , Arteria Ilíaca/cirugía , Isquemia/cirugía , Pierna/irrigación sanguínea , Recuperación del Miembro , Adulto , Arteriopatías Oclusivas/mortalidad , Aterosclerosis/mortalidad , Causas de Muerte , Femenino , Estudios de Seguimiento , Oclusión de Injerto Vascular/mortalidad , Humanos , Isquemia/mortalidad , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Factores de Riesgo , Tasa de Supervivencia
4.
Eur Rev Med Pharmacol Sci ; 25(3): 1511-1521, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33629320

RESUMEN

OBJECTIVE: Coronary artery bypass grafting (CABG) seems to present a powerful trigger of oxidative stress (OS) and acute inflammatory response. This study aimed to estimate the effects of off-pump coronary artery bypass (OPCAB) grafting on the OS that is commonly observed in patients undergoing operation under cardiopulmonary bypass (CPB). Additionally, we aimed to examine the relationship between and paraoxonase 1 (PON1) activity and the degree of stenosis, severity and complexity of the atherosclerotic lesions, estimated by SYNTAX score (SS). PATIENTS AND METHODS: Study group of 107 patients scheduled for CABG were divided into CPB and OPCAB group. Blood samples for OS markers measurement were collected at six-time intervals: before skin incision (t1), immediately after surgery (t2), 6h (t3), 24h (t4), 48h (t5) and 96h after cessation of the operation and surgical trauma (t6). SS was calculated. RESULTS: A significant decrease in lipid hydroperoxides (LOOH) and advanced oxidation protein products (AOPP) levels after both types of surgeries were observed, whereas PON1 reduction was observed higher in the CPB than in the OPCAB group. A significant inverse correlation between SS values and PON1 activity, preoperatively and during the early postoperative hours after surgery [in t2, t3 time intervals (p<0.05 for all)] was found. ROC analysis showed that for CPB patients, Model with all OS parameters showed excellent accuracy (AUC=0.957, p<0.001) for prediction postoperative complications. CONCLUSIONS: Decrease in PON1 activity during the early post-operative phases was related to higher SS. This relationship was more convincing in CPB, compared with OPCAB patients. Moreover, integrated models of OS status parameters have the capability to predict the development of postoperative complications.


Asunto(s)
Arildialquilfosfatasa/metabolismo , Puente Cardiopulmonar/efectos adversos , Puente de Arteria Coronaria/efectos adversos , Complicaciones Posoperatorias/metabolismo , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
5.
Phys Rev Lett ; 105(21): 213901, 2010 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-21231306

RESUMEN

Using a combination of the variation approximation and direct simulations, we consider the model of the light transmission in nonlinearly amplified bulk media, taking into account the localization of the gain, i.e., the linear loss shaped as a parabolic function of the transverse radius, with a minimum at the center. The balance of the transverse diffraction, self-focusing, gain, and the inhomogeneous loss provides for the hitherto elusive stabilization of vortex solitons, in a large zone of the parameter space. Adjacent to it, stability domains are found for several novel kinds of localized vortices, including spinning elliptically shaped ones, eccentric elliptic vortices which feature double rotation, spinning crescents, and breathing vortices.

6.
Biol Sex Differ ; 11(1): 36, 2020 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-32631423

RESUMEN

BACKGROUND: Studies have recently examined the role of epigenetic mechanisms in preeclampsia pathophysiology. One commonly examined epigenetic process is DNA methylation. This heritable epigenetic marker is involved in many important cellular functions. The aim of this study was to establish the association between DNA methylation and preeclampsia and to critically appraise the roles of major study characteristics that can significantly impact the association between DNA methylation and preeclampsia. MAIN BODY: A systematic review was performed by searching PubMed, Web of Science, and EMBASE for original research articles published over time, until May 31, 2019 in English. Eligible studies compared DNA methylation levels in pregnant women with vs. without preeclampsia. Ninety articles were included. Epigenome-wide studies identified hundreds of differentially methylated places/regions in preeclamptic patients. Hypomethylation was the predominant finding in studies analyzing placental tissue (14/19), while hypermethylation was detected in three studies that analyzed maternal white blood cells (3/3). In candidate gene studies, methylation alterations for a number of genes were found to be associated with preeclampsia. A greater number of differentially methylated genes was found when analyzing more severe preeclampsia (70/82), compared to studies analyzing less severe preeclampsia vs. controls (13/27). A high degree of heterogeneity existed among the studies in terms of methodological study characteristics including design (study design, definition of preeclampsia, control group, sample size, confounders), implementation (biological sample, DNA methylation method, purification of DNA extraction, and validation of methylation), analysis (analytical method, batch effect, genotyping, and gene expression), and data presentation (methylation quantification measure, measure of variability, reporting). Based on the results of this review, we provide recommendations for study design and analytical approach for further studies. CONCLUSIONS: The findings from this review support the role of DNA methylation in the pathophysiology of preeclampsia. Establishing field-wide methodological and analytical standards may increase value and reduce waste, allowing researchers to gain additional insights into the role of DNA methylation in the pathophysiology of preeclampsia.


Asunto(s)
Metilación de ADN , Epigénesis Genética , Preeclampsia/genética , Preeclampsia/fisiopatología , Femenino , Predisposición Genética a la Enfermedad , Humanos , Embarazo
7.
Opt Express ; 17(14): 11698-709, 2009 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-19582084

RESUMEN

Dynamical and steady-state behavior of beams propagating in nematic liquid crystals (NLCs) is analyzed. A well-known model for the beam propagation and the director reorientation angle in a NLC cell is treated numerically in space and time. The formation of steady-state soliton breathers in a threshold region of beam intensities is displayed. Below the region the beams diffract, above the region spatiotemporal instabilities develop, as the input intensity and the material parameters are varied. Curiously, the only kind of solitons we could demonstrate in our numerical studies was the breathers. Despite repeated efforts, we could not find the solitons with a steady profile propagating in the NLC model at hand.

8.
Cerebrovasc Dis ; 28(6): 589-94, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19844099

RESUMEN

BACKGROUND: Previous data are conflicting as to whether imbalance between hemostatic factors is associated with clinical strokes. We evaluated the association between hemostatic factor levels and subclinical lacunar infarcts in a nested sample from a subset of the Atherosclerosis Risk in Communities (ARIC) cohort. METHODS: 196 cases without clinical strokes had lacunar infarcts by MRI, and 214 controls without radiographic infarcts were frequency-matched by age group and sex. Logistic regression models were fitted to assess the association between levels of hemostatic markers and case status. RESULTS: In age-, race- and sex-adjusted models, von Willebrand factor (vWF) and D-dimer were positively associated with case status, with odds ratios for the highest vs. lowest tertile of 2.0 (95% CI 1.2-3.6) for vWF and 1.76 (95% CI 1.02-3.0) for D-dimer. Plasminogen had nonsignificant inverse associations with presence of silent lacunar infarcts. CONCLUSIONS: vWF and D-dimer were positively associated, and plasminogen was nonsignificantly inversely associated with subclinical radiographic infarct. Further studies on the role of these hemostatic factors in the development of silent lacunar infarcts may help elucidate the mechanisms behind this injury and may even point to potential targets for future intervention.


Asunto(s)
Infarto Encefálico/sangre , Infarto Encefálico/epidemiología , Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Plasminógeno/metabolismo , Factor de von Willebrand/metabolismo , Aterosclerosis/epidemiología , Biomarcadores/sangre , Infarto Encefálico/patología , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Modelos Logísticos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos/epidemiología
9.
Opt Express ; 14(25): 12310-5, 2006 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-19529659

RESUMEN

The behavior of counterpropagating self-trapped optical beam structures in nematic liquid crystals is investigated. A time-dependent model for the beam propagation and the director reorientation in a nematic liquid crystal is numerically treated in three spatial dimensions and time. We find that the stable vector solitons can only exist in a narrow threshold region of control parameters. Below this region the beams diffract, above they self-focus into a series of focal spots. Spatiotemporal instabilities are observed as the input intensity, the propagation distance, and the birefringence are increased. We demonstrate undulation, filamentation, and convective dynamical instabilities of counterpropagating beams. Qualitatively similar behavior as of the copropagating beams is observed, except that it happens at lower values of control parameters.

10.
Biochim Biophys Acta ; 1269(2): 167-75, 1995 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-7488650

RESUMEN

We determined the expression of isoforms of prostaglandin H synthase (PGHS) and thromboxane A synthase (TXAS) in a human megakaryocyte cell line (MEG-01. The basal levels of full-length TXAS mRNA and the 60 kDa TXAS protein were high when compared to those of PGHS-1 and PGHS-2 in uninduced cells. Despite a high TXAS level, uninduced MEG-01 cells synthesized only a small amount of thromboxane A2 (TXA2) due to limited PGHS-1 or PGHS-2 expressions. Following PMA induction there was little change in TXAS. PGHS-2 mRNA was significantly increased at only 3 h of PMA treatment and the level declined rapidly, whereas PGHS-1 mRNA and protein levels were concordantly stimulated. Induction of PGHS-1 reached plateau on day 3 of PMA treatment. Analysis of arachidonate metabolism in cells induced by PMA for 3 and 5 days showed a high level of PGH2 synthesis which exceeded the TXAS capacity for TXA2 synthesis. Only traces of PGHS-2 mRNA and alternate-spliced TXAS mRNA were detected in human platelets. We conclude that TXAS and PGHS are differentially expressed in MEG-01 during PMA-induced differentiation.


Asunto(s)
Megacariocitos/enzimología , Prostaglandina-Endoperóxido Sintasas/biosíntesis , Tromboxano-A Sintasa/biosíntesis , Secuencia de Bases , Plaquetas , Western Blotting , Diferenciación Celular , Línea Celular , Eicosanoides/análisis , Humanos , Isoenzimas/biosíntesis , Megacariocitos/efectos de los fármacos , Microsomas , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Prostaglandina-Endoperóxido Sintasas/genética , ARN Mensajero/análisis , Radioinmunoensayo , Acetato de Tetradecanoilforbol/farmacología , Tromboxano A2/análisis , Tromboxano-A Sintasa/genética
11.
Circulation ; 103(10): 1386-9, 2001 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-11245641

RESUMEN

BACKGROUND: Thrombomodulin (TM) is expressed on the endothelial surface and plays an important role in vasoprotection. A common polymorphism of TM at amino acid position 455 with an alanine (A) to valine (V) transition was previously reported to be associated cross-sectionally with acute myocardial infarction. Whether this single nucleotide polymorphism predicts risk of developing coronary heart disease (CHD) is unclear. METHODS AND RESULTS: Within a large cohort study, we identified 467 incident CHD cases during an average of 5 years of follow-up. We determined TM-455 genotypes on 376 CHD cases (23% black, 77% white) and a reference sample of 461. The AA genotype was significantly more prevalent in noncases than in cases (P:=0.016). The prevalences of the AA genotype in noncase blacks and whites were 93% and 67%, respectively. The AA genotype frequency was significantly reduced in black cases versus noncases (P:=0.018). It was also lower in white cases than in noncases, but the difference was not statistically significant (P:=0.066). Weighted proportional hazards regression analysis after adjustment for age, sex, and other CHD risk factors showed that having the V allele increased risk of CHD by 6.1-fold (risk ratio 6.1, 95% CI 1.7 to 22.9) in blacks but did not significantly increase the risk in whites. CONCLUSIONS: The TM A455V polymorphism predicts risk of developing CHD in blacks.


Asunto(s)
Enfermedad Coronaria/genética , Polimorfismo Genético , Trombomodulina/genética , Adulto , Población Negra , Estudios de Cohortes , Enfermedad Coronaria/epidemiología , Enfermedad Coronaria/etnología , Femenino , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo
12.
Circulation ; 102(16): 1901-5, 2000 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-11034936

RESUMEN

BACKGROUND: The major platelet integrin glycoprotein IIb-IIIa plays a primary role in platelet aggregation and acute thrombus formation at the site of vascular injury. A genetic polymorphism of glycoprotein IIb-IIIa (Pl(A)) has recently been proposed as a potential genetic factor linking to platelet hyperaggregability and increased risk of myocardial infarction. Despite numerous, mostly nonprospective studies, the role of this polymorphism as a clinically relevant, inherited risk factor for coronary heart disease (CHD) is still controversial. The purpose of this study was to determine whether Pl(A2) is a risk factor for incident CHD and whether it is correlated with increased platelet activation in a case-cohort study nested within a prospective epidemiologic investigation. METHODS AND RESULTS: Blood samples were collected and processed from the Atherosclerosis Risk in Communities Study cohort at the baseline examination (1987 to 1989). They were stored at -80 degrees C. Pl(A1/A2) genotype and plasma beta-thromboglobulin levels were determined in 439 incident CHD cases and a reference cohort sample of 544 (of whom 18 were also CHD cases). The prevalence of the Pl(A2) allele was not different in cases versus noncases. No significant correlation between CHD risk factors and the Pl(A2) allele was noted either. Platelet activation, as measured by plasma beta-thromboglobulin levels, was not enhanced in individuals with the Pl(A2) allele. CONCLUSIONS: This prospective study indicates that healthy individuals carrying the Pl(A2) allele do not have an increased risk of CHD.


Asunto(s)
Alelos , Antígenos de Plaqueta Humana/genética , Enfermedad Coronaria/genética , Antígenos de Plaqueta Humana/sangre , Estudios de Casos y Controles , Estudios de Cohortes , Enfermedad Coronaria/epidemiología , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Activación Plaquetaria/genética , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Polimorfismo de Longitud del Fragmento de Restricción , Estudios Prospectivos , Análisis de Regresión , Factores de Riesgo , Estudios Seroepidemiológicos , beta-Tromboglobulina/metabolismo
13.
Circulation ; 100(7): 736-42, 1999 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-10449696

RESUMEN

BACKGROUND: Several markers of hemostatic function and inflammation have been associated with increased risk of coronary heart disease, but prospective evidence for their role in ischemic stroke is scant. METHODS AND RESULTS: The Atherosclerosis Risk in Communities (ARIC) Study measured several of these markers in more than 14 700 participants 45 to 64 years old who were free of cardiovascular disease and were followed up for 6 to 9 years for occurrence of ischemic stroke (n=191). There was no apparent association between ischemic stroke incidence and factor VIIc, antithrombin III, platelet count, or activated partial thromboplastin time. After adjustment for multiple cardiovascular risk factors, von Willebrand factor, factor VIIIc, fibrinogen, and white blood cell count were positively associated and protein C was negatively but nonsignificantly associated with ischemic stroke incidence in regression analyses based on either continuous variables or fourths of the variable distributions. The adjusted relative risk (and 95% CI) for ischemic stroke in those in the highest versus lowest fourth were: von Willebrand factor, 1.71 (1.1 to 2.7); factor VIIIc, 1.93 (1.2 to 3.1); white blood cell count, 1.50 (0.9 to 2.4); fibrinogen, 1.26 (0.8 to 2.0); and protein C, 0.65 (0.4 to 1.0). CONCLUSIONS: This study offers modest support for the hypothesis that some markers of hemostatic function and inflammation can identify groups of middle-aged adults at increased risk of stroke. These factors may play a role in the pathogenesis of ischemic stroke.


Asunto(s)
Isquemia Encefálica/epidemiología , Factor VIII/análisis , Fibrinógeno/análisis , Hemostasis , Recuento de Leucocitos , Factor de von Willebrand/análisis , Arteriosclerosis/epidemiología , Biomarcadores/sangre , Glucemia/análisis , Proteínas Sanguíneas/análisis , Isquemia Encefálica/sangre , Estudios de Cohortes , Comorbilidad , Diabetes Mellitus/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Lípidos/sangre , Masculino , Persona de Mediana Edad , Tiempo de Tromboplastina Parcial , Recuento de Plaquetas , Estudios Prospectivos , Factores de Riesgo , Texas/epidemiología
14.
Arterioscler Thromb Vasc Biol ; 21(4): 611-7, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11304480

RESUMEN

The fibrinolytic system may play a role in the pathogenesis of coronary heart disease (CHD), but existing prospective studies have not consistently shown an independent association between fibrinolytic factors and CHD. None has reported an association between plasminogen and CHD incidence. In the prospective Atherosclerosis Risk in Communities (ARIC) Study of middle-aged adults, we examined the association of incident CHD with several fibrinolytic factors: tissue plasminogen activator antigen, plasminogen activator inhibitor-1, plasminogen, and fibrin fragment D-dimer as well as a marker of coagulation activation (prothrombin fragment F1.2). We measured these in stored baseline plasma samples of 326 subjects who developed CHD and, for comparison, a stratified random sample of the entire cohort (n=720). Tissue plasminogen activator and plasminogen activator inhibitor-1 antigen levels were associated positively with CHD incidence in analyses adjusted for age, race, and sex but were not associated with CHD after adjustment for other risk factors. Plasminogen and D-dimer levels were associated positively and independently with CHD incidence; the multivariable-adjusted relative risks (95% CIs) for the highest versus lowest quintiles were 2.20 (1.2 to 4.2) for plasminogen and 4.21 (1.9 to 9.6) for D-dimer. F1.2 was not associated with CHD incidence. Our findings lend support for a link between fibrinolytic factors and CHD incidence. A positive association between plasminogen and CHD is seemingly opposite the direction expected but may reflect a compensatory response to impaired plasminogen activation in subjects prone to CHD.


Asunto(s)
Enfermedad de la Arteria Coronaria/sangre , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Fragmentos de Péptidos/sangre , Inhibidor 1 de Activador Plasminogénico/sangre , Plasminógeno/análisis , Activador de Tejido Plasminógeno/sangre , Biomarcadores , Estudios de Cohortes , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/epidemiología , Femenino , Fibrinólisis , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Protrombina , Muestreo , Estados Unidos/epidemiología
15.
J Thromb Haemost ; 1(1): 88-94, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12871544

RESUMEN

Plasma thrombomodulin (soluble TM; sTM) is considered to be a marker of endothelial injury, but a recent report indicated that the relationship of sTM with thrombosis is complex. Venous thromboembolic events were identified in adults in two longitudinal cohort studies, the Atherosclerosis Risk in Communities Study and the Cardiovascular Health Study, totaling 21 690 participants. After 8 years of follow-up, sTM was measured in baseline plasma of 305 participants who developed venous thrombosis and 607 who did not. Thrombomodulin A455V genotype was determined in 302 cases and 626 controls. There was no difference in the prevalence of the three TM genotypes between cases and controls and no difference in age-adjusted mean values of sTM by genotype. There were no associations of age-adjusted sTM or TMA455V genotype with overall venous thromboembolism or with thrombosis in any subtype of venous thromboembolism.


Asunto(s)
Tromboembolia/sangre , Tromboembolia/genética , Trombomodulina/sangre , Trombomodulina/genética , Trombosis de la Vena/sangre , Trombosis de la Vena/genética , Factores de Edad , Anciano , Sustitución de Aminoácidos , Estudios de Casos y Controles , Femenino , Genotipo , Humanos , Incidencia , Masculino , Polimorfismo Genético , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Tromboembolia/epidemiología , Trombosis de la Vena/epidemiología
16.
Atherosclerosis ; 157(2): 309-14, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11472730

RESUMEN

Thrombomodulin, an endothelial membrane glycoprotein, is an essential part of the protein C anti-coagulant pathway. It may also have a role in the regulation of fibrinolysis. We carried out a cross-sectional study to assess the association of soluble thrombomodulin (sTM) with peripheral artery disease (PAD) in a stratified random sample (n=863) of otherwise healthy black and white participants of the Atherosclerosis Risk in Communities (ARIC) Study. PAD was more common in black than in white participants and associated with classical risk factors in an expected manner; positively with age, smoking, hypertension, diabetes (P=0.05), and LDL-cholesterol, and inversely with HDL-cholesterol. Significant positive associations were observed also with fibrinogen and white blood cell count. Overall, the sTM concentration was not a significant predictor of PAD. The association was, however, modified by the level of factor VIII:C in whites (P=0.002 for the interaction), but not in blacks. Protein C was inversely associated with PAD prevalence (odds ratio 0.33, 95% CI 0.18--0.61, P=0.0004). sTM was inversely associated with plasminogen, but no associations with t-PA, PAI-1, or D-dimer were seen. In conclusion, the present results provide some additional evidence on the role of thrombomodulin-protein C pathway in atherosclerotic disease and support our earlier observation on interaction between sTM and factor VIII:C.


Asunto(s)
Arteriosclerosis/sangre , Trombomodulina/sangre , Negro o Afroamericano , Arteriosclerosis/epidemiología , Arteriosclerosis/etiología , Estudios de Cohortes , Estudios Transversales , Factor VIII/análisis , Humanos , Persona de Mediana Edad , Plasminógeno/análisis , Prevalencia , Proteína C/análisis , Valores de Referencia , Factores de Riesgo , Solubilidad , Estados Unidos/epidemiología , Población Blanca
17.
Ann Epidemiol ; 11(3): 166-70, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11293402

RESUMEN

PURPOSE: The -455G/A (HaeIII) polymorphism of the beta-fibrinogen gene influences levels of plasma fibrinogen. We determined whether it influences risk of coronary heart disease. METHODS: We conducted a case-cohort study nested within a prospective investigation, the Atherosclerosis Risk in Communities Study. We accumulated 398 incident coronary heart disease cases over a median of 5.3 years of follow-up and compared their -455G/A status with a random sample of the cohort (n = 498). RESULTS: Plasma fibrinogen was higher (p = 0.04) in AA homozygous participants (341 mg/dL) than in persons carrying the G allele: GA (290 mg/dL), GG (298 mg/dL). However, there was no significant association between -455G/A and incident CHD. CONCLUSIONS: Although a small effect cannot be excluded, -455G/A does not appear to be an important genetic determinant of CHD.


Asunto(s)
Arteriosclerosis/epidemiología , Enfermedad Coronaria/epidemiología , Fibrinógeno/genética , Polimorfismo Genético , Adenina , Alelos , Arteriosclerosis/sangre , Arteriosclerosis/genética , Estudios de Cohortes , Enfermedad Coronaria/sangre , Enfermedad Coronaria/genética , Fibrinógeno/análisis , Genotipo , Guanina , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Estados Unidos/epidemiología
18.
Toxicon ; 21(6): 887-92, 1983.
Artículo en Inglés | MEDLINE | ID: mdl-6658810

RESUMEN

V. ammodytes ammodytes snake venom produced irreversible block of the isolated, artificially stimulated rat right ventricle or isolated rat heart. This was the result of degenerative changes of the myocardium caused by the direct effect of toxic components of the venom. An excess of Ca2+ could temporarily restart the contractions.


Asunto(s)
Calcio/farmacología , Corazón/efectos de los fármacos , Venenos de Víboras/farmacología , Animales , Contracción Miocárdica/efectos de los fármacos , Miocardio/patología , Ratas
19.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(5 Pt 2): 057601, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11736151

RESUMEN

The nonlinear dynamics of laser beams carrying phase singularity in media with cubic-quintic nonlinearity changing from self-focusing to self-defocusing is examined. A novel kind of stable nonlocalized optical vortices appears in such media as well as localized vortex solitons. Linear stability analysis and numerical simulations show the stability of localized vortices only in the defocusing region.

20.
Phlebology ; 29(2): 98-104, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22987234

RESUMEN

OBJECTIVES: Condition known as chronic cerebrospinal venous insufficiency (CCSVI) is characterized by insufficient cerebral vein drainage in patients with multiple sclerosis (MS) and internal jugular vein (IJV), vertebral and/or azygos veins stenoses. However, external compression on the IJV was not clearly described as a potential cause of CCSVI. We aim to present a case of CCSVI in a patient with MS caused by bilateral IJV inverted valves combined with IJV external compression by carotid bulb. METHODS: A 31-year-old female patient was admitted to our institute for IJV and vertebral veins morphological and haemodynamical assessment after being treated for MS for the last 14 years. Colour Doppler ultrasonography showed right IJV prestenotic dilation and inverted valves in both IJV. Computerized tomography angiography showed bilateral IJV compression by carotid bulb. Haemodynamical Doppler parameters showed that external IJV compression significantly contributed to CCSVI occurrence. RESULTS: Bilateral IJV confluence percutaneous angioplasty (PTA) was done, and the patient was discharged for further neurological examination. Partial carbon dioxide pressure was significantly lower in the distal part of both IJV following PTA and oxygen saturation increased. CONCLUSION: In the case presented, PTA of the IJV confluence resulted in haemodynamic improvement despite the presence of IJV external compression.


Asunto(s)
Venas Yugulares/diagnóstico por imagen , Esclerosis Múltiple/fisiopatología , Insuficiencia Venosa/fisiopatología , Adulto , Angiografía , Angioplastia , Vena Ácigos/fisiopatología , Femenino , Hemodinámica , Humanos , Rayos Láser , Esclerosis Múltiple/complicaciones , Oxígeno/química , Presión , Tomografía Computarizada por Rayos X , Ultrasonografía Doppler , Insuficiencia Venosa/complicaciones
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