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1.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;48(5): 427-432, 05/2015. tab
Artículo en Inglés | LILACS | ID: lil-744368

RESUMEN

Community-acquired pneumonia (CAP) is amongst the leading causes of death worldwide. As inflammatory markers, cytokines can predict outcomes, if interpreted together with clinical data and scoring systems such as CURB-65, CRB, and Acute Physiology and Chronic Health Evaluation II (APACHE II). The aim of this study was to determine the impact of inflammatory biomarkers on the early mortality of hospitalized CAP patients. Twenty-seven CAP patients needing hospitalization were enrolled for the study and samples of interleukin-1 (IL-1) and interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), C-reactive protein (CRP), and homocystein were collected at the time of admission (day 1) as well as on the seventh day of the treatment. There was a significant reduction in the levels of IL-6 between the first and the second collections. Median IL-6 values decreased from 24 pg/mL (day 1) to 8 pg/mL (day 7) (P=0.016). The median levels of TNF-α were higher in patients: i) with acute kidney injury (AKI) (P=0.045), ii) requiring mechanical ventilation (P=0.040), iii) with short hospital stays (P=0.009), iv) admitted to the intensive care unit (ICU) (P=0.040), v) who died early (P=0.003), and vi) with worse CRB scores (P=0.013). In summary, IL-6 and TNF-α levels were associated with early mortality of CAP patients. Longer admission levels demonstrated greater likelihood of early death and overall mortality, necessity of mechanical ventilation, and AKI.


Asunto(s)
Adolescente , Humanos , Financiación Gubernamental , Centros de Tratamiento de Abuso de Sustancias/organización & administración , Trastornos Relacionados con Sustancias/rehabilitación , Bases de Datos Factuales , Garantía de la Calidad de Atención de Salud , Calidad de la Atención de Salud , Centros de Tratamiento de Abuso de Sustancias/normas , Centros de Tratamiento de Abuso de Sustancias/tendencias , Estados Unidos
3.
Braz J Med Biol Res ; 48(5): 427-32, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25714883

RESUMEN

Community-acquired pneumonia (CAP) is amongst the leading causes of death worldwide. As inflammatory markers, cytokines can predict outcomes, if interpreted together with clinical data and scoring systems such as CURB-65, CRB, and Acute Physiology and Chronic Health Evaluation II (APACHE II). The aim of this study was to determine the impact of inflammatory biomarkers on the early mortality of hospitalized CAP patients. Twenty-seven CAP patients needing hospitalization were enrolled for the study and samples of interleukin-1 (IL-1) and interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), C-reactive protein (CRP), and homocystein were collected at the time of admission (day 1) as well as on the seventh day of the treatment. There was a significant reduction in the levels of IL-6 between the first and the second collections. Median IL-6 values decreased from 24 pg/mL (day 1) to 8 pg/mL (day 7) (P=0.016). The median levels of TNF-α were higher in patients: i) with acute kidney injury (AKI) (P=0.045), ii) requiring mechanical ventilation (P=0.040), iii) with short hospital stays (P=0.009), iv) admitted to the intensive care unit (ICU) (P=0.040), v) who died early (P=0.003), and vi) with worse CRB scores (P=0.013). In summary, IL-6 and TNF-α levels were associated with early mortality of CAP patients. Longer admission levels demonstrated greater likelihood of early death and overall mortality, necessity of mechanical ventilation, and AKI.


Asunto(s)
Interleucina-6/sangre , Neumonía/mortalidad , Factor de Necrosis Tumoral alfa/sangre , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Proteína C-Reactiva/análisis , Niño , Preescolar , Infecciones Comunitarias Adquiridas/complicaciones , Infecciones Comunitarias Adquiridas/mortalidad , Creatinina/sangre , Femenino , Homocisteína/sangre , Humanos , Lactante , Recién Nacido , Interleucina-1/sangre , Tiempo de Internación , Masculino , Persona de Mediana Edad , Neumonía/complicaciones , Estudios Prospectivos , Respiración Artificial , Factores Sexuales , Estadísticas no Paramétricas , Adulto Joven
6.
Braz J Med Biol Res ; 46(5): 454-9, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23681289

RESUMEN

A low concentration of nitric oxide associated with a high concentration of asymmetric dimethylarginine (ADMA) can explain the lack of ischemic cardioprotection observed in the presence of hypercholesterolemia. The objective of the present study was to evaluate the effect of hypercholesterolemia on ischemic pre- and postconditioning and its correlation with plasma concentrations of ADMA. Male Wistar rats (6-8 weeks old) fed a 2% cholesterol diet (n = 21) for 8 weeks were compared to controls (n = 25) and were subjected to experimental myocardial infarction and reperfusion, with ischemic pre- and postconditioning. Total cholesterol and ADMA were measured in plasma before the experimental infarct and the infarct area was quantified. Weight, total cholesterol and plasma ADMA (means ± SE; 1.20 ± 0.06, 1.27 ± 0.08 and 1.20 ± 0.08 vs 0.97 ± 0.04, 0.93 ± 0.05 and 0.97 ± 0.04 µM) were higher in animals on the hypercholesterolemic diet than in controls, respectively. Cardioprotection did not reduce infarct size in the hypercholesterolemic animals (pre: 13.55% and post: 8% compared to 7.95% observed in the group subjected only to ischemia and reperfusion), whereas infarct size was reduced in the animals on a normocholesterolemic diet (pre: 8.25% and post: 6.10% compared to 12.31%). Hypercholesterolemia elevated ADMA and eliminated the cardioprotective effects of ischemic pre- and postconditioning in rats.


Asunto(s)
Arginina/análogos & derivados , Hipercolesterolemia/sangre , Infarto del Miocardio/etiología , Animales , Arginina/sangre , Colesterol/sangre , Colesterol en la Dieta , Modelos Animales de Enfermedad , Hipercolesterolemia/complicaciones , Hipercolesterolemia/patología , Precondicionamiento Isquémico Miocárdico , Masculino , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Ratas , Ratas Wistar
7.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;46(5): 454-459, maio 2013. tab
Artículo en Inglés | LILACS | ID: lil-675670

RESUMEN

A low concentration of nitric oxide associated with a high concentration of asymmetric dimethylarginine (ADMA) can explain the lack of ischemic cardioprotection observed in the presence of hypercholesterolemia. The objective of the present study was to evaluate the effect of hypercholesterolemia on ischemic pre- and postconditioning and its correlation with plasma concentrations of ADMA. Male Wistar rats (6-8 weeks old) fed a 2% cholesterol diet (n = 21) for 8 weeks were compared to controls (n = 25) and were subjected to experimental myocardial infarction and reperfusion, with ischemic pre- and postconditioning. Total cholesterol and ADMA were measured in plasma before the experimental infarct and the infarct area was quantified. Weight, total cholesterol and plasma ADMA (means ± SE; 1.20 ± 0.06, 1.27 ± 0.08 and 1.20 ± 0.08 vs 0.97 ± 0.04, 0.93 ± 0.05 and 0.97 ± 0.04 µM) were higher in animals on the hypercholesterolemic diet than in controls, respectively. Cardioprotection did not reduce infarct size in the hypercholesterolemic animals (pre: 13.55% and post: 8% compared to 7.95% observed in the group subjected only to ischemia and reperfusion), whereas infarct size was reduced in the animals on a normocholesterolemic diet (pre: 8.25% and post: 6.10% compared to 12.31%). Hypercholesterolemia elevated ADMA and eliminated the cardioprotective effects of ischemic pre- and postconditioning in rats.


Asunto(s)
Animales , Masculino , Ratas , Arginina/análogos & derivados , Hipercolesterolemia/sangre , Infarto del Miocardio/etiología , Arginina/sangre , Colesterol en la Dieta , Colesterol/sangre , Modelos Animales de Enfermedad , Hipercolesterolemia/complicaciones , Hipercolesterolemia/patología , Precondicionamiento Isquémico Miocárdico , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Ratas Wistar
8.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;44(10): 973-991, Oct. 2011. ilus
Artículo en Inglés | LILACS | ID: lil-600691

RESUMEN

In this article, we compare two strategies for atherosclerosis treatment: drugs and healthy lifestyle. Statins are the principal drugs used for the treatment of atherosclerosis. Several secondary prevention studies have demonstrated that statins can significantly reduce cardiovascular events including coronary death, the need for surgical revascularization, stroke, total mortality, as well as fatal and non-fatal myocardial infarction. These results were observed in both men and women, the elderly, smokers and non-smokers, diabetics and hypertensives. Primary prevention studies yielded similar results, although total mortality was not affected. Statins also induce atheroma regression and do not cause cancer. However, many unresolved issues remain, such as partial risk reduction, costs, several potential side effects, and long-term use by young patients. Statins act mainly as lipid-lowering drugs but pleiotropic actions are also present. Healthy lifestyle, on the other hand, is effective and inexpensive and has no harmful effects. Five items are associated with lower cardiac risk: non-smoking, BMI ≤25, regular exercise (30 min/day), healthy diet (fruits, vegetables, low-saturated fat, and 5-30 g alcohol/day). Nevertheless, there are difficulties in implementing these measures both at the individual and population levels. Changes in behavior require multidisciplinary care, including medical, nutritional, and psychological counseling. Participation of the entire society is required for such implementation, i.e., universities, schools, media, government, and medical societies. Although these efforts represent a major challenge, such a task must be faced in order to halt the atherosclerosis epidemic that threatens the world.


Asunto(s)
Femenino , Humanos , Masculino , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/prevención & control , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Enfermedad de la Arteria Coronaria/prevención & control , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Estilo de Vida , Factores de Riesgo
9.
Braz J Med Biol Res ; 44(10): 973-91, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21876872

RESUMEN

In this article, we compare two strategies for atherosclerosis treatment: drugs and healthy lifestyle. Statins are the principal drugs used for the treatment of atherosclerosis. Several secondary prevention studies have demonstrated that statins can significantly reduce cardiovascular events including coronary death, the need for surgical revascularization, stroke, total mortality, as well as fatal and non-fatal myocardial infarction. These results were observed in both men and women, the elderly, smokers and non-smokers, diabetics and hypertensives. Primary prevention studies yielded similar results, although total mortality was not affected. Statins also induce atheroma regression and do not cause cancer. However, many unresolved issues remain, such as partial risk reduction, costs, several potential side effects, and long-term use by young patients. Statins act mainly as lipid-lowering drugs but pleiotropic actions are also present. Healthy lifestyle, on the other hand, is effective and inexpensive and has no harmful effects. Five items are associated with lower cardiac risk: non-smoking, BMI ≤25, regular exercise (30 min/day), healthy diet (fruits, vegetables, low-saturated fat, and 5-30 g alcohol/day). Nevertheless, there are difficulties in implementing these measures both at the individual and population levels. Changes in behavior require multidisciplinary care, including medical, nutritional, and psychological counseling. Participation of the entire society is required for such implementation, i.e., universities, schools, media, government, and medical societies. Although these efforts represent a major challenge, such a task must be faced in order to halt the atherosclerosis epidemic that threatens the world.


Asunto(s)
Aterosclerosis/tratamiento farmacológico , Aterosclerosis/prevención & control , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Enfermedad de la Arteria Coronaria/prevención & control , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Estilo de Vida , Femenino , Humanos , Masculino , Factores de Riesgo
10.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;44(5): 469-476, May 2011. ilus, tab
Artículo en Inglés | LILACS | ID: lil-586512

RESUMEN

Dyslipidemia is related to the progression of atherosclerosis and is an important risk factor for acute coronary syndromes. Our objective was to determine the effect of rosuvastatin on myocardial necrosis in an experimental model of acute myocardial infarction (AMI). Male Wistar rats (8-10 weeks old, 250-350 g) were subjected to definitive occlusion of the left anterior descending coronary artery to cause AMI. Animals were divided into 6 groups of 8 to 11 rats per group: G1, normocholesterolemic diet; G2, normocholesterolemic diet and rosuvastatin (1 mg·kg-1·day-1) 30 days after AMI; G3, normocholesterolemic diet and rosuvastatin (1 mg·kg-1·day-1) 30 days before and after AMI; G4, hypercholesterolemic diet; G5, hypercholesterolemic diet and rosuvastatin (1 mg·kg-1·day-1) 30 days after AMI; G6, hypercholesterolemic diet and rosuvastatin (1 mg·kg-1·day-1) 30 days before and after AMI. Left ventricular function was determined by echocardiography and percent infarct area by histology. Fractional shortening of the left ventricle was normal at baseline and decreased significantly after AMI (P < 0.05 in all groups), being lower in G4 and G5 than in the other groups. No significant difference in fractional shortening was observed between G6 and the groups on the normocholesterolemic diet. Percent infarct area was significantly higher in G4 than in G3. No significant differences were observed in infarct area among the other groups. We conclude that a hypercholesterolemic diet resulted in reduced cardiac function after AMI, which was reversed with rosuvastatin when started 30 days before AMI. A normocholesterolemic diet associated with rosuvastatin before and after AMI prevented myocardial necrosis when compared with the hypercholesterolemic condition.


Asunto(s)
Animales , Masculino , Ratas , Fluorobencenos/uso terapéutico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Infarto del Miocardio/patología , Miocardio/patología , Pirimidinas/uso terapéutico , Sulfonamidas/uso terapéutico , Colesterol en la Dieta/efectos adversos , Modelos Animales de Enfermedad , Ecocardiografía , Hipercolesterolemia/complicaciones , Hipercolesterolemia/tratamiento farmacológico , Infarto del Miocardio/etiología , Necrosis/prevención & control , Ratas Wistar
11.
Braz J Med Biol Res ; 44(5): 469-76, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21445530

RESUMEN

Dyslipidemia is related to the progression of atherosclerosis and is an important risk factor for acute coronary syndromes. Our objective was to determine the effect of rosuvastatin on myocardial necrosis in an experimental model of acute myocardial infarction (AMI). Male Wistar rats (8-10 weeks old, 250-350 g) were subjected to definitive occlusion of the left anterior descending coronary artery to cause AMI. Animals were divided into 6 groups of 8 to 11 rats per group: G1, normocholesterolemic diet; G2, normocholesterolemic diet and rosuvastatin (1 mg·kg(-1)·day-1) 30 days after AMI; G3, normocholesterolemic diet and rosuvastatin (1 mg·kg(-1)·day-1) 30 days before and after AMI; G4, hypercholesterolemic diet; G5, hypercholesterolemic diet and rosuvastatin (1 mg·kg(-1)·day-1) 30 days after AMI; G6, hypercholesterolemic diet and rosuvastatin (1 mg·kg(-1)·day-1) 30 days before and after AMI. Left ventricular function was determined by echocardiography and percent infarct area by histology. Fractional shortening of the left ventricle was normal at baseline and decreased significantly after AMI (P < 0.05 in all groups), being lower in G4 and G5 than in the other groups. No significant difference in fractional shortening was observed between G6 and the groups on the normocholesterolemic diet. Percent infarct area was significantly higher in G4 than in G3. No significant differences were observed in infarct area among the other groups. We conclude that a hypercholesterolemic diet resulted in reduced cardiac function after AMI, which was reversed with rosuvastatin when started 30 days before AMI. A normocholesterolemic diet associated with rosuvastatin before and after AMI prevented myocardial necrosis when compared with the hypercholesterolemic condition.


Asunto(s)
Fluorobencenos/uso terapéutico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Infarto del Miocardio/patología , Miocardio/patología , Pirimidinas/uso terapéutico , Sulfonamidas/uso terapéutico , Animales , Colesterol en la Dieta/efectos adversos , Modelos Animales de Enfermedad , Ecocardiografía , Hipercolesterolemia/complicaciones , Hipercolesterolemia/tratamiento farmacológico , Masculino , Infarto del Miocardio/etiología , Necrosis/prevención & control , Ratas , Ratas Wistar , Rosuvastatina Cálcica
12.
Braz J Med Biol Res ; 39(6): 825-32, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16751990

RESUMEN

Myocardial contrast echocardiography has been used for assessing myocardial perfusion. Some concerns regarding its safety still remain, mainly regarding the induction of microvascular alterations. We sought to determine the bioeffects of microbubbles and real-time myocardial contrast echocardiography (RTMCE) in a closed-chest canine model. Eighteen mongrel dogs were randomly assigned to two groups. Nine were submitted to continuous intravenous infusion of perfluorocarbon-exposed sonicated dextrose albumin (PESDA) plus continuous imaging using power pulse inversion RTMCE for 180 min, associated with manually deflagrated high-mechanical index impulses. The control group consisted of 3 dogs submitted to continuous imaging using RTMCE without PESDA, 3 dogs received PESDA alone, and 3 dogs were sham-operated. Hemodynamics and cardiac rhythm were monitored continuously. Histological analysis was performed on cardiac and pulmonary tissues. No hemodynamic changes or cardiac arrhythmias were observed in any group. Normal left ventricular ejection fraction and myocardial perfusion were maintained throughout the protocol. Frequency of mild and focal microhemorrhage areas in myocardial and pulmonary tissue was similar in PESDA plus RTMCE and control groups. The percentages of positive microscopical fields in the myocardium were 0.4 and 0.7% (P = NS) in the PESDA plus RTMCE and control groups, respectively, and in the lungs they were 2.1 and 1.1%, respectively (P = NS). In this canine model, myocardial perfusion imaging obtained with PESDA and RTMCE was safe, with no alteration in cardiac rhythm or left ventricular function. Mild and focal myocardial and pulmonary microhemorrhages were observed in both groups, and may be attributed to surgical tissue manipulation.


Asunto(s)
Ecocardiografía/métodos , Glucosa , Microburbujas , Miocardio/ultraestructura , Albúmina Sérica , Animales , Perros , Infusiones Intravenosas , Albúmina Sérica Humana , Función Ventricular Izquierda
13.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;39(6): 825-832, June 2006. ilus, tab
Artículo en Inglés | LILACS | ID: lil-428273

RESUMEN

Myocardial contrast echocardiography has been used for assessing myocardial perfusion. Some concerns regarding its safety still remain, mainly regarding the induction of microvascular alterations. We sought to determine the bioeffects of microbubbles and real-time myocardial contrast echocardiography (RTMCE) in a closed-chest canine model. Eighteen mongrel dogs were randomly assigned to two groups. Nine were submitted to continuous intravenous infusion of perfluorocarbon-exposed sonicated dextrose albumin (PESDA) plus continuous imaging using power pulse inversion RTMCE for 180 min, associated with manually deflagrated high-mechanical index impulses. The control group consisted of 3 dogs submitted to continuous imaging using RTMCE without PESDA, 3 dogs received PESDA alone, and 3 dogs were sham-operated. Hemodynamics and cardiac rhythm were monitored continuously. Histological analysis was performed on cardiac and pulmonary tissues. No hemodynamic changes or cardiac arrhythmias were observed in any group. Normal left ventricular ejection fraction and myocardial perfusion were maintained throughout the protocol. Frequency of mild and focal microhemorrhage areas in myocardial and pulmonary tissue was similar in PESDA plus RTMCE and control groups. The percentages of positive microscopical fields in the myocardium were 0.4 and 0.7 percent (P = NS) in the PESDA plus RTMCE and control groups, respectively, and in the lungs they were 2.1 and 1.1 percent, respectively (P = NS). In this canine model, myocardial perfusion imaging obtained with PESDA and RTMCE was safe, with no alteration in cardiac rhythm or left ventricular function. Mild and focal myocardial and pulmonary microhemorrhages were observed in both groups, and may be attributed to surgical tissue manipulation.


Asunto(s)
Animales , Perros , Ecocardiografía/métodos , Glucosa , Microburbujas , Miocardio/ultraestructura , Albúmina Sérica , Infusiones Intravenosas , Función Ventricular Izquierda
14.
Braz J Med Biol Res ; 39(4): 455-63, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16612468

RESUMEN

Hyperhomocystinemia has been related to an increased risk of cardiovascular disease in several studies. The C677T polymorphism for the gene that encodes the methylenetetrahydrofolate reductase enzyme (MTHFR) and low plasma folate levels are common causes of hyperhomocystinemia. Due to differences in nutritional patterns and genetic background among different countries, we evaluated the role of hyperhomocystinemia as a coronary artery disease (CAD) risk factor in a Brazilian population. The relation between homocysteine (Hcy) and the extent of CAD, measured by an angiographic score, was determined. A total of 236 patients referred for coronary angiography for clinical reasons were included. CAD was found in 148 (62.7%) patients and 88 subjects had normal or near normal arteries. Patients with CAD had higher Hcy levels [mean (SD)] than those without disease (14 (6.8) vs 12.5 (4.0) microM; P = 0.04). Hyperhomocystinemia (Hcy >17.8 microM) prevalence was higher in the CAD group: 31.1 vs 12.2% (P = 0.01). After adjustment for major risk factors, we found an independent association between hyperhomocystinemia and CAD (OR = 2.48; 95% CI = 1.02-6.14). Patients with a more advanced coronary score had a higher frequency of hyperhomocystinemia and tended to have higher mean Hcy levels. An inverse relation between plasma folate and Hcy levels was found (r = -0.14; P = 0.04). Individuals with the MTHFR C677T polymorphism had a higher prevalence of hyperhomocystinemia than those without the mutated allele. We conclude that hyperhomocystinemia is independently associated with CAD, with a positive association between Hcy level and disease severity.


Asunto(s)
Enfermedad de la Arteria Coronaria/sangre , Homocisteína/sangre , Hiperhomocisteinemia/complicaciones , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/enzimología , Enfermedad de la Arteria Coronaria/genética , Estudios Transversales , Femenino , Humanos , Hiperhomocisteinemia/enzimología , Hiperhomocisteinemia/genética , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Factores de Riesgo , Índice de Severidad de la Enfermedad
15.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;39(4): 455-463, Apr. 2006. tab
Artículo en Inglés | LILACS | ID: lil-425075

RESUMEN

Hyperhomocystinemia has been related to an increased risk of cardiovascular disease in several studies. The C677T polymorphism for the gene that encodes the methylenetetrahydrofolate reductase enzyme (MTHFR) and low plasma folate levels are common causes of hyperhomocystinemia. Due to differences in nutritional patterns and genetic background among different countries, we evaluated the role of hyperhomocystinemia as a coronary artery disease (CAD) risk factor in a Brazilian population. The relation between homocysteine (Hcy) and the extent of CAD, measured by an angiographic score, was determined. A total of 236 patients referred for coronary angiography for clinical reasons were included. CAD was found in 148 (62.7 percent) patients and 88 subjects had normal or near normal arteries. Patients with CAD had higher Hcy levels [mean (SD)] than those without disease (14 (6.8) vs 12.5 (4.0) æM; P = 0.04). Hyperhomocystinemia (Hcy >17.8 æM) prevalence was higher in the CAD group: 31.1 vs 12.2 percent (P = 0.01). After adjustment for major risk factors, we found an independent association between hyperhomocystinemia and CAD (OR = 2.48; 95 percent CI = 1.02-6.14). Patients with a more advanced coronary score had a higher frequency of hyperhomocystinemia and tended to have higher mean Hcy levels. An inverse relation between plasma folate and Hcy levels was found (r = -0.14; P = 0.04). Individuals with the MTHFR C677T polymorphism had a higher prevalence of hyperhomocystinemia than those without the mutated allele. We conclude that hyperhomocystinemia is independently associated with CAD, with a positive association between Hcy level and disease severity.


Asunto(s)
Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de la Arteria Coronaria/sangre , Homocisteína/sangre , Hiperhomocisteinemia/complicaciones , /genética , Angiografía Coronaria , Estudios Transversales , Enfermedad de la Arteria Coronaria/enzimología , Enfermedad de la Arteria Coronaria/genética , Hiperhomocisteinemia/enzimología , Hiperhomocisteinemia/genética , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Factores de Riesgo , Índice de Severidad de la Enfermedad
16.
Braz J Med Biol Res ; 38(5): 661-7, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15917946

RESUMEN

The aim of the present study was to evaluate the role of magnetic resonance imaging (MRI) for the non-invasive detection of coronary abnormalities and specifically the remodeling process in patients with coronary artery disease (CAD). MRI was performed in 10 control healthy subjects and 26 patients with angiographically proven CAD of the right coronary (RCA) or left anterior descending (LAD) artery; 23 patients were within two months of acute coronary syndromes, and 3 had stable angina with a positive test for ischemia. Wall thickness (WT), vessel wall area (VWA), total vessel area (TVA), and luminal area (LA) were measured. There were significant increases in WT (mean +/- SEM, RCA: 2.62 +/- 0.75 vs 0.53 +/- 0.15 mm; LAD: 2.21 +/- 0.69 vs 0.62 +/- 0.24 mm) and in VWA (RCA: 30.96 +/- 17.57 vs 2.1 +/- 1.2 mm(2); LAD: 19.53 +/- 7.25 vs 3.6 +/- 2.0 mm(2)) patients compared to controls (P < 0.001 for each variable). TVA values were also greater in patients compared to controls (RCA: 44.56 +/- 21.87 vs 12.3 +/- 4.2 mm(2); LAD: 31.89 +/- 11.31 vs 17.0 +/- 6.2 mm(2); P < 0.001). In contrast, the LA did not differ between patients and controls for RCA or LAD. When the LA was adjusted for vessel size using the LA/TVA ratio, a significant difference was found: 0.33 +/- 0.16 in patients vs 0.82 +/- 0.09 in controls (RCA) and 0.38 +/- 0.13 vs 0.78 +/- 0.06 (LAD) (P < 0.001). As opposed to normal controls, positive remodeling was present in all patients with CAD, as indicated by larger VWA. We conclude that MRI detected vessel wall abnormalities and was an effective tool for the noninvasive evaluation of the atherosclerotic process and coronary vessel wall modifications, including positive remodeling that frequently occurs in patients with acute coronary syndromes.


Asunto(s)
Enfermedad de la Arteria Coronaria/diagnóstico , Anomalías de los Vasos Coronarios/diagnóstico , Imagen por Resonancia Magnética , Adulto , Anciano , Estudios de Casos y Controles , Enfermedad de la Arteria Coronaria/patología , Anomalías de los Vasos Coronarios/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad
17.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;38(5): 661-667, May 2005. ilus, tab
Artículo en Inglés | LILACS | ID: lil-400965

RESUMEN

The aim of the present study was to evaluate the role of magnetic resonance imaging (MRI) for the non-invasive detection of coronary abnormalities and specifically the remodeling process in patients with coronary artery disease (CAD). MRI was performed in 10 control healthy subjects and 26 patients with angiographically proven CAD of the right coronary (RCA) or left anterior descending (LAD) artery; 23 patients were within two months of acute coronary syndromes, and 3 had stable angina with a positive test for ischemia. Wall thickness (WT), vessel wall area (VWA), total vessel area (TVA), and luminal area (LA) were measured. There were significant increases in WT (mean ± SEM, RCA: 2.62 ± 0.75 vs 0.53 ± 0.15 mm; LAD: 2.21 ± 0.69 vs 0.62 ± 0.24 mm) and in VWA (RCA: 30.96 ± 17.57 vs 2.1 ± 1.2 mm²; LAD: 19.53 ± 7.25 vs 3.6 ± 2.0 mm²) patients compared to controls (P < 0.001 for each variable). TVA values were also greater in patients compared to controls (RCA: 44.56 ± 21.87 vs 12.3 ± 4.2 mm²; LAD: 31.89 ± 11.31 vs 17.0 ± 6.2 mm²; P < 0.001). In contrast, the LA did not differ between patients and controls for RCA or LAD. When the LA was adjusted for vessel size using the LA/TVA ratio, a significant difference was found: 0.33 ± 0.16 in patients vs 0.82 ± 0.09 in controls (RCA) and 0.38 ± 0.13 vs 0.78 ± 0.06 (LAD) (P < 0.001). As opposed to normal controls, positive remodeling was present in all patients with CAD, as indicated by larger VWA. We conclude that MRI detected vessel wall abnormalities and was an effective tool for the noninvasive evaluation of the atherosclerotic process and coronary vessel wall modifications, including positive remodeling that frequently occurs in patients with acute coronary syndromes.


Asunto(s)
Adulto , Persona de Mediana Edad , Humanos , Masculino , Femenino , Enfermedad de la Arteria Coronaria/diagnóstico , Anomalías de los Vasos Coronarios/diagnóstico , Imagen por Resonancia Magnética , Estudios de Casos y Controles
18.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;37(9): 1313-1320, Sept. 2004. ilus, tab, graf
Artículo en Inglés | LILACS | ID: lil-365219

RESUMEN

The objective of the present study was to determine the relationship between nitric oxide synthases (NOS) and heart failure in cardiac tissue from patients with and without cardiac decompensation. Right atrial tissue was excised from patients with coronary artery disease (CAD) and left ventricular ejection fraction (LVEF) <35 percent (N = 10), and from patients with CAD and LVEF >60 percent (N = 10) during cardiac surgery. NOS activity was measured by the conversion of L-[H ]-arginine to L-[H ]-citrulline. Gene expression was quantified by the competitive reverse transcription-polymerase chain reaction. Both endothelial NOS (eNOS) activity and expression were significantly reduced in failing hearts compared to non-failing hearts: 0.36 ± 0.18 vs 1.51 ± 0.31 pmol mg-1 min-1 (P < 0.0001) and 0.37 ± 0.08 vs 0.78 ± 0.09 relative cDNA absorbance at 320 nm (P < 0.0001), respectively. In contrast, inducible NOS (iNOS) activity and expression were significantly higher in failing hearts than in non-failing hearts: 4.00 ± 0.90 vs 1.54 ± 0.65 pmol mg-1 min-1 (P < 0.0001) and 2.19 ± 0.27 vs 1.43 ± 0.13 cDNA absorbance at 320 nm (P < 0.0001), respectively. We conclude that heart failure down-regulates both eNOS activity and expression in cardiac tissue from patients with LVEF <35 percent. In contrast, iNOS activity and expression are increased in failing hearts and may represent an alternative mechanism for nitric oxide production in heart failure due to ischemic disease.


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Enfermedad de la Arteria Coronaria , Expresión Génica , Insuficiencia Cardíaca , Angiografía Coronaria , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
19.
Braz J Med Biol Res ; 37(9): 1313-20, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15334196

RESUMEN

The objective of the present study was to determine the relationship between nitric oxide synthases (NOS) and heart failure in cardiac tissue from patients with and without cardiac decompensation. Right atrial tissue was excised from patients with coronary artery disease (CAD) and left ventricular ejection fraction (LVEF) <35% (N = 10), and from patients with CAD and LVEF >60% (N = 10) during cardiac surgery. NOS activity was measured by the conversion of L-[H(3)]-arginine to L-[H(3)]-citrulline. Gene expression was quantified by the competitive reverse transcription-polymerase chain reaction. Both endothelial NOS (eNOS) activity and expression were significantly reduced in failing hearts compared to non-failing hearts: 0.36 +/- 0.18 vs 1.51 +/- 0.31 pmol mg-1 min-1 (P < 0.0001) and 0.37 +/- 0.08 vs 0.78 +/- 0.09 relative cDNA absorbance at 320 nm (P < 0.0001), respectively. In contrast, inducible NOS (iNOS) activity and expression were significantly higher in failing hearts than in non-failing hearts: 4.00 +/- 0.90 vs 1.54 +/- 0.65 pmol mg-1 min-1 (P < 0.0001) and 2.19 +/- 0.27 vs 1.43 +/- 0.13 cDNA absorbance at 320 nm (P < 0.0001), respectively. We conclude that heart failure down-regulates both eNOS activity and expression in cardiac tissue from patients with LVEF <35%. In contrast, iNOS activity and expression are increased in failing hearts and may represent an alternative mechanism for nitric oxide production in heart failure due to ischemic disease.


Asunto(s)
Enfermedad de la Arteria Coronaria/complicaciones , Insuficiencia Cardíaca/enzimología , Óxido Nítrico Sintasa/metabolismo , Anciano , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/cirugía , Femenino , Expresión Génica , Insuficiencia Cardíaca/etiología , Humanos , Masculino , Persona de Mediana Edad , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa de Tipo II , Óxido Nítrico Sintasa de Tipo III , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
20.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;36(11): 1501-1509, Nov. 2003. ilus, graf
Artículo en Inglés | LILACS | ID: lil-348294

RESUMEN

Differentiation between stunned and infarcted myocardium in the setting of acute ischemia is challenging. Real time myocardial contrast echocardiography allows the simultaneous assessment of myocardial perfusion and function. In the present study we evaluated infarcted and stunned myocardium in an experimental model using real time myocardial contrast echocardiography. Sixteen dogs underwent 180 min of coronary occlusion followed by reperfusion (infarct model) and seven other dogs were submitted to 20 min of coronary occlusion followed by reperfusion (stunned model). Wall motion abnormality and perfusional myocardial defect areas were measured by planimetry. Risk and infarct areas were determined by tissue staining. In the infarct model, the wall motion abnormality area during coronary occlusion (5.52 ± 1.14 cm²) was larger than the perfusional myocardial defect area (3.71 ± 1.45 cm²; P < 0.001). Reperfusion resulted in maintenance of wall motion abnormality (5.45 ± 1.41 cm²; P = 0.43 versus occlusion) and reduction of perfusional myocardial defect (1.51 ± 1.29 cm²; P = 0.004 versus occlusion). Infarct size determined by contrast echocardiography correlated with tissue staining (r = 0.71; P = 0.002). In the stunned model, the wall motion abnormality area was 5.49 ± 0.68 cm² during occlusion and remained 5.1 ± 0.63 cm² after reperfusion (P = 0.07). Perfusional defect area was 2.43 ± 0.79 cm² during occlusion and was reduced to 0.2 ± 0.53 cm² after reperfusion (P = 0.04). 2,3,5-Triphenyl tetrazolium chloride staining confirmed the absence of necrotic myocardium in all dogs in the stunned model. Real time myocardial contrast echocardiography is a noninvasive technique capable of distinguishing between stunned and infarcted myocardium after acute ischemia.


Asunto(s)
Animales , Perros , Ecocardiografía , Infarto del Miocardio , Colorantes , Medios de Contraste , Modelos Animales de Enfermedad , Estudio de Evaluación , Fluorocarburos , Infarto del Miocardio , Aturdimiento Miocárdico , Factores de Riesgo
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