CONTEO DE PLAQUETAS EN SUJETOS SANOS TRATADOS CON ANTIAGREGANTES PLAQUETARIOS / PLATELET COUNT IN HEALTHY SUBJECTS TREATED WITH ANTIPLATELET DRUGS

Se evaluó el recuento plaquetario en sangre periférica de sujetos sanos tratados con antiagregantes plaquetarios. Se analizaron 20 sujetos. Se distribuyeron en dos grupos: A: 10 sujetos que recibieron Aspirina (100 mg) y B: 10 con Clopidogrel (75 mg) por 7 días. Se les realizó recuento plaquetario en sangre periférica y en PRP. Encontrándose un conteo de plaquetas antes del tratamiento con antiagregantes en sangre periférica de 258,6 ± 54,46 x 109 l 7 días después de 254 ± 41,86 x 109 l (Aspirina), 285,4±70,92 y 196,5±37,90 x 109 l (Clopidogrel) respectivamente. En el PRP de los sujetos antes de recibir Aspirina fue 486,5 ± 129,54 x 109 l y después 449,2 ± 85,51 x 109 l; antes de la ingestión de Clopidogrel fue 565,2 ± 150,41 y 592,9 ± 203,46 x 109 l después del tratamiento. Se encontraron diferencias significativas solo para el conteo plaquetario en el grupo del Clopidogrel (p< 0.05). Se observó una disminución significativa del conteo plaquetario en sangre periférica posterior a la administración del Clopidogrel, posiblemente como consecuencia del mecanismo farmacológico del mismo. Son necesarios más estudios para evaluar un mayor número de individuos y medir mejor el efecto de los antiplaquetarios.

Platelet count in peripheral blood of healthy subjects with antiplatelet drugs. 20 subjects were analized. They were distributed in two groups: subject A: 10 who received aspirin (100 mg) and B:10 with Clopidogrel (75 mg) for 7 days. In all subjects studied platelet count in peripheral blood and PRP. It found a platelet count before treatment with antiplatelet agents in peripheral blood of 258,6 ± 54,46 x 109 l and 7 days after 254 ± 41,86 x 109 l (aspirin) and 285,4 ± 70, 196,5 ± 37,90 x 109 l (Clopidogrel) respectively. In the PRP of subjects before receiving aspirin was 486,5 ± 129,54 x 109 l and after 449,2 ± 85,51 x 109 l; prior to Clopidogrel ingestion was 565,2 ± 150,41 and 592,9 ± 203,46 x 109 l after treatment. Significant differences were found only for the platelet count in the Clopidogrel Group (p < 0.05). A significant decrease in platelet count was observed in peripheral blood after administration of Clopidogrel, possibly as a result of its pharmacological mechanism. More studies are needed to assess a greater number of individuals and better measure the effect of antiplatelet agents.

Aplicación del plasma rico en plaquetas (PRP) y sus derivados en implantología dental y cirugía plástica / Application of platelet rich plasma (PRP) and its derivatives in dental implantologie and plastic surgery

El Plasma Rico en Plaquetas (PRP), como su nombre lo indica, posee una alta concentración de trombocitos; es un preparado autólogo, no tóxico y no alergénico, obtenido por centrifugación de la sangre a baja velocidad. Su función está directamente ligada a la liberación por parte de las plaquetas de Factores de Crecimiento (FC). Estos factores tienen propiedades de inducción de la regeneración de los tejidos. Para la elaboración del presente trabajo se realizó una búsqueda bibliográfica en diferentes fuentes documentales utilizando los descriptores: Plasma rico en plaquetas, PRP, Factores de crecimiento, FC, Odontología y Cirugía estética. En este artículo se realiza una descripción de algunos aspectos relevantes del PRP y su aplicación en las áreas de Odontología y Cirugía estética.

The platelet rich plasma (PRP), as its name implies, has a high concentration of thrombocytes; is a non-toxic and non-allergenic autologous preparation, obtained by blood centrifugation at low speed. Its function is directly linked to the release of growth factors (FC) by platelets. These factors have properties of induction of tissue regeneration. For the preparation of the present work, a literature search was performed in different documentary sources using the following descriptors: platelet rich plasma, PRP, growth factors, GF, dentistry and cosmetic surgery. This article is a description of some relevant aspects of the PRP and its application in the areas of dentistry and cosmetic surgery.

[Application of platelet rich plasma (PRP) and its derivatives in dental implantologie and plastic surgery]. / Aplicación del plasma rico en plaquetas (PRP) y sus derivados en implantología dental y cirugía plástica.

The platelet rich plasma (PRP), as its name implies, has a high concentration of thrombocytes; is a non-toxic and non-allergenic autologous preparation, obtained by blood centrifugation at low speed. Its function is directly linked to the release of growth factors (FC) by platelets. These factors have properties of induction of tissue regeneration. For the preparation of the present work, a literature search was performed in different documentary sources using the following descriptors: platelet rich plasma, PRP, growth factors, GF, dentistry and cosmetic surgery. This article is a description of some relevant aspects of the PRP and its application in the areas of dentistry and cosmetic surgery.

[Use of warfarin and low range INR in the prevention of recurrent venous thrombosis]. / Uso de warfarina y bajo rango de INR en la prevención de trombosis venosa recurrente.

The object of this work was to determine the efficacy of a low range International Normalized Ratio (INR) between 1.5 and 1.9, in preventing recurrent venous thrombosis and the hemorrhagic manifestations that can complicate anticoagulation with warfarin. Thirty nine patients, 10 to 78 years of age were studied between January 2006 and November 2009. All of them had been treated with warfarin, for at least 6 months, due to deep venous thrombosis or pulmonary embolism. The subjects were separated, at random, into two groups. In group A (20 patients), the doses of warfarin were adjusted until the INR was stabilized between 1.5 and 1.9; in group B, the INR was maintained between 2 and 3. The coagulant activities of plasma factors II, VII, IX and X were determined in a week and between the fourth and fifth weeks, after stabilization of the INR. Plasma activities of the coagulation factors assayed were abnormally low in both groups, in the two opportunities they were determined, although significantly lower in group B (p<0.05). No thromboembolic episodes occurred during the study, in any of the patients. One of the patients from group A and four from group B, presented minor hemorrhagic manifestations (p N.S.) The above results suggest that a range on INR lower that 2, could be sufficient to prevent recurrent thrombotic episodes while diminishing the frequency of hemorrhagic complications associated with the use of warfarin. However, it is necessary to continue incorporating more individuals in the study to obtain greater certainty in the analysis of these results.

Uso de warfarina y bajo rango de INR en la prevención de trombosis venosa recurrente / Use of warfarin and low range INR in the prevention of recurrent venous thrombosis

El objetivo de este trabajo fue determinar la efectividad de un rango de la Razón Normalizada Internacional (INR) entre 1,5 y 1,9 en la prevención de la recurrencia de trombosis venosa y de las complicaciones hemorrágicas asociadas al uso de warfarina. Entre enero del 2006 y noviembre del 2009, se estudiaron 39 pacientes, con edades entre 10 y 78 años y diagnóstico de trombosis venosa profunda y/o embolismo pulmonar que recibieron warfarina al menos durante 6 meses. Los sujetos fueron separados aleatoriamente en dos grupos: a 20 pacientes se le ajustó la dosis para mantener el INR entre 1,5 y 1,9 y a 19 pacientes se les mantuvo el INR entre 2 y 3. A cada individuo se le cuantificó la actividad plasmática de los factores II, VII, IX y X a la primera y entre la cuarta y quinta semanas, luego de estabilizado el INR. En ambos grupos, la actividad de los factores se encontró por debajo del valor normal con diferencia significativa entre los grupos (p<0,05). No se detectó recurrencia de trombosis durante el seguimiento. Solo se presentaron manifestaciones hemorrágicas menores en un sujeto con INR entre 1,5 y 1,9 y en cuatro del otro grupo (p = NS). Los resultados del presente trabajo sugieren que un rango de INR entre 1,5 y 1,9, provee un esquema de anticoagulación eficaz para la prevención de recurrencia de trombosis venosa con menor frecuencia de hemorragias. Sin embargo, es necesario seguir incorporando más individuos en el estudio para obtener mayor certeza en el análisis de estos resultados.

The object of this work was to determine the efficacy of a low range International Normalized Ratio (INR) between 1.5 and 1.9, in preventing recurrent venous thrombosis and the hemorrhagic manifestations that can complicate anticoagulation with warfarin. Thirty nine patients, 10 to 78 years of age were studied between January 2006 and November 2009. All of them had been treated with warfarin, for at least 6 months, due to deep venous thrombosis or pulmonary embolism. The subjects were separated, at random, into two groups. In group A (20 patients), the doses of warfarin were adjusted until the INR was stabilized between 1.5 and 1.9; in group B, the INR was maintained between 2 and 3. The coagulant activities of plasma factors II, VII, IX and X were determined in a week and between the fourth and fifth weeks, after stabilization of the INR. Plasma activities of the coagulation factors assayed were abnormally low in both groups, in the two opportunities they were determined, although significantly lower in group B (p<0.05). No thromboembolic episodes occurred during the study, in any of the patients. One of the patients from group A and four from group B, presented minor hemorrhagic manifestations (p N.S.) The above results suggest that a range on INR lower that 2, could be sufficient to prevent recurrent thrombotic episodes while diminishing the frequency of hemorrhagic complications associated with the use of warfarin. However, it is necessary to continue incorporating more individuals in the study to obtain greater certainty in the analysis of these results.

Polimorfismos intragénicos de los genes de los factores VIII y IX y su utilidad en el diagnóstico indirecto de portadoras de hemofilias A y B / Intragenic polymorphisms of factor VIII and IX genes and their utility in the indirect diagnosis of carriers of haemophilias A and B

Las Hemofilias A y B se consideran enfermedades hereditarias ligadas al sexo debidas a mutaciones en los genes que codifican para los factores VIII y IX respectivamente, ocasionando deficiencia en los niveles de la concentración plasmática de estas proteínas y cuyos roles son los de participar activamente en el mecanismo de la coagulación sanguínea. Se han reportado diversas mutaciones responsables de la alteración de estos genes; razón por la cual resulta poco práctico la aplicación de un método de diagnóstico molecular directo para la identificación de mujeres portadoras, por ello, una estrategia diagnóstica apropiada es el análisis indirecto de polimorfismos ligados al gen. El objetivo de este trabajo fue identificar mujeres portadoras en diversas familias con antecedentes de HA y HB residentes del estado Zulia, en Venezuela, caracterizando polimorfismos intragénicos de los genes del factor VIII y factor IX, los cuales permitieron asignar haplotipos y diagnosticar o descartar el estado portador al 95 por ciento de las mujeres que requerían el estudio para HA y al 100 por ciento para HB.

Haemophilia A and B are considered sex-linked inherited diseases caused by mutations in genes that encode factors VIII and IX, respectively. This results in the deficiency of these proteins plasma levels which are actively involved in the mechanism of blood coagulation. It has been reported that several mutations are responsible for the alteration of these genes, which is why the application of a molecular diagnostic method for the direct identification of female carriers is impractical. An appropriate diagnostic strategy is the indirect analysis of polymorphisms linked to the gene. The aim of this study was to identify female carriers in different families with history of HA and HB that live in Zulia State, Venezuela, characterizing intragenic gene polymorphisms of the clotting factors VIII and IX, which helped to identify and assign haplotypes, to diagnose or to exclude the carrying condition, to 95 percent of women who were needing the study for HA and to 100 percent for HB.

[Intragenic polymorphisms of factor VIII and IX genes and their utility in the indirect diagnosis of carriers of Haemophilias A and B]. / Polimorfismos intragénicos de los genes de los factores VIII y IX y su utilidad en el diagnóstico indirecto de portadoras de Hemofilias A y B.

Haemophilia A and B are considered sex-linked inherited diseases caused by mutations in genes that encode factors VIII and IX, respectively. This results in the deficiency of these proteins plasma levels which are actively involved in the mechanism of blood coagulation. It has been reported that several mutations are responsible for the alteration of these genes, which is why the application of a molecular diagnostic method for the direct identification of female carriers is impractical. An appropriate diagnostic strategy is the indirect analysis of polymorphisms linked to the gene. The aim of this study was to identify female carriers in different families with history of HA and HB that live in Zulia State, Venezuela, characterizing intragenic gene polymorphisms of the clotting factors VIII and IX, which helped to identify and assign haplotypes, to diagnose or to exclude the carrying condition, to 95% of women who were needing the study for HA and to 100% for HB.

Manejo odontológico del paciente con terapia antitrombotica / Dental management of patient with antithrombotic therapy

El presente manuscrito tiene como objetivo proporcionar una revisión bibliográfica del manejo odontológico del paciente que recibe terapia antitrombótica, debido a que las personas con enfermedad cardiovascular frecuentemente reciben este tipo de terapia y constituyen una amplia población en Venezuela, y junto a la alta prevalencia de caries y enfermedad periodontal, es necesario que los odontólogos y especialistas estén actualizados sobre el manejo de estos pacientes ya que, el tratamiento quirúrgico y no quirúrgico de las afecciones bucales pueden desencadenar complicaciones hemorrágicas y la suspensión del medicamento puede producir la aparición de un fenómeno trombótico, por otro lado, la terapéutica farmacológica empleada comúnmente en odontología puede interactuar con el tratamiento médico y provocar complicaciones; para el manejo de estos pacientes, es importante utilizar los agentes hemostáticos locales para evitar y controlar el sangrado intraoperatorio y postoperatorio.

The objective of the present work is to give information related to the dental management of patient receiving antithrombotic therapy, since people with heart disease frequently receive this kind of therapy, and they range a wide population in Venezuela , in addition to the high prevalence of cavities and periodontal disease ; therefore, it is necessary the specialists and dentist to be updated on the management of those patients, because the surgical and non surgical dental treatment may lead to hemorrhagic complications and on one hand, the withdrawal of medication may cause the onset of a thrombotic phenomenon, on the other hand, the pharmacological therapy commonly used in dentistry may interact to the medical treatment and cause complications; for managing those patients, it is important to use the haemostatic agents in order to avoid and control the local bleeding.

Evaluating periodontal conditions in patients with von Willebrand's disease in Hospital Universitario de Maracaibo (University Hospital, Maracaibo)-Venezuela.

OBJECTIVE: To evaluate the periodontal conditions of patients with von Willebrand's Disease (vWD who went for dental examination in the "Area of attention to patients with systemic disease" of the University Hospital in Maracaibo, Venezuela. DESIGN OF THE STUDY: 40 patients (28 female and 12 male), with ages ranging from 10 to 72 years, who regularly attended dental control, were evaluated along with a control group of patients with no hemorrhagic alterations. Periodontal conditions were evaluated using the Löe and Silness Gingival Index (GI) and Greene and Vermillon's Simplified Oral Hygiene Index (SOHI). The results were analyzed using averages, Standard Deviation, Student's T-test and the Chi(2) test, with P<0.0005. RESULTS: 92.5% of the patients had Type 1 vWD and 7.5% had Type 2 or 3. Periodontal Indices: GI (0.70+/-0.40, slight) and SOHI (1,70+/-0,80, acceptable). Comparison with the control group showed that there were statistically significant differences in the SOHI (P = 0.02). CONCLUSIONS: Periodontal conditions in patients with vWD regularly attending for dental control were within acceptable parameters. Education of the patient with regard to prevention and opportune treatment is of utmost importance, thereby avoiding the oral hemorrhagic complications produced by the periodontal disease. Of equal importance is multidisciplinary teamwork.

Evaluating periodontal conditions in patients with von Willebrand’s disease in Hospital Universitario de Maracaibo (University Hospital, Maracaibo) -Venezuela

Objective: To evaluate the periodontal conditions of patients with von Willebrand’s Disease (vWD) who went fordental examination in the “Area of attention to patients with systemic disease” of the University Hospital in Maracaibo, Venezuela. Design of the Study: 40 patients (28 female and 12 male), with ages ranging from 10 to 72 years, who regularly attended dental control, were evaluated along with a control group of patients with no hemorrhagicalterations. Periodontal conditions were evaluated using the Löe and Silness Gingival Index (GI) and Greene andVermillon’s Simplified Oral Hygiene Index (SOHI). The results were analyzed using averages, Standard Deviation,Student’s T-test and the Chi² test, with P<0.0005. Results: 92.5% of the patients had Type 1 vWD and 7.5% had Type 2 or 3. Periodontal Indices: GI (0.70±0.40, slight) and SOHI (1,70±0,80, acceptable). Comparison with the control group showed that there were statistically significant differences in the SOHI (P = 0.02). Conclusions: Periodontal conditions in patients with vWD regularly attending for dental control were within acceptable parameters. Education of the patient with regard to prevention and opportune treatment is of utmost importance, thereby avoiding the oral hemorrhagic complications produced by the periodontal disease. Of equal importance is multidisciplinary teamwork (AU)

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Changes in blood pressure in children undergoing psychological treatment before dental procedures.

Different dental procedures in children undergoing treatment can induce changes in blood pressure. These changes will be minimized if psychological treatment is applied prior to any procedure. The objective of this study was to determine changes in blood pressure (systolic-diastolic) in children undergoing psychological treatment before dental procedures. The population studied consisted of 100 children and adolescents, ages 6 to 15 years. The patients were assigned to two groups at random, i.e. with or without psychological treatment before dental procedures. Behavior management was carried out applying the tell-show-do technique of conduct handling. The systolic and diastolic blood pressures were measured prior to the initiation of the treatment, during drilling, restoring, and before dismissing the patient. The no-psychological treatment group exhibited significant differences in diastolic and systolic blood pressures during the dental procedure whereas the psychological treatment group evidenced no significant differences in blood pressure. No correlation was found between the alterations of blood pressure and the type of dental treatment performed. The application of the tell-show-do method would have an effect on the blood pressure in patients undergoing dental procedures.

[Hepatitis B in children with cancer]. / Hepatitis B en niños con cáncer.

INTRODUCTION: Cancer patients can be asymptomatic carriers of the hepatitis B virus (HBV), which can be reactivated by chemotherapy. Our aim was to identify the serological markers of HBV in children with cancer who were asymptomatic carriers of the virus. Fifty two (52) children with cancer treated at the Maracaibo University Hospital in Venezuela were studied, 28 of these children (53.8%) were HBV positive, despite no clinical or biochemical signs or symptoms of hepatitis. The type of serological markers present in each of these children.were investigated. We found 7 cases (25%) with hepatitis B surface antigen (HBsAg) and 2 (7.1%) with anticore as the only markers. Multiple markers were found in the other children: 9 (32.1%) HBsAg and anticore; 7 (25%) HBsAg, e-antigen (HBeAg) and anticore; 3 (10.7%) HBsAg, HBeAg antibody and anticore. In total, of the 28 positive children 20 (71.4%) showed positive anticore and of these 4 (20%) were of the IgM type. Our results show a high level of positivity for HBV in the children with cancer studied. In spite of being asymptomatic carriers of the HBV, it is noticeable the presence of serological markers for acute disease. We recommend testing for HBV serological markers before starting chemotherapy. Should the test results be negative, vaccination is indicated and should they be positive, specialized care is indicated.

[Social functioning and psychopathologic risk factors in hemophilic children]. / Funcionamiento social en niños hemofílicos. Análisis de encuesta para determinar factores psicopatológicos de riesgo.

BACKGROUND: Children with hemophilia can experience problems with their mental health status and social functioning. AIM: To assess the mental health status of hemophilic children. MATERIAL AND METHODS: Thirty four hemophilic children aged 5 to 13 years were studied. A translation of the special survey to assess mental health in children, denominated "Domingo" Mental Health Survey was applied. It consisted in animated cartoon questions related to the family, social and school life. According to the score obtained, children were classified as normal, doubtful or pathologic. The social functioning areas studied were family, school, relationship and emotional. Aggressiveness, depression/anxiety and rejection were the psychopathologic factors analyzed. RESULTS: Forty four percent of hemophilic children were considered normal, 20% doubtful and 35% pathologic. According to the severity of the disease, 67% of children with severe, 57% with moderate and 45% with mild hemophilia, were considered abnormal. Aggressiveness was the main risk factor in the emotional and family area, depression/anxiety in the family and emotional area and rejection in the family area. Fifty six percent of children had abnormalities in their social functioning and the severity of the disease was a predisposing factor. CONCLUSIONS: Psychopathologic factors in children with hemophilia appear mainly in the family environment.

Funcionamiento social en niños hemofílicos: Análisis de encuesta para determinar factores psicopatológicos de riesgo / Social functioning and psychopathologic risk factors in hemophilic children

Background: Children with hemophilia can experience problems with their mental health status and social functioning. Aim: To assess the mental health status of hemophilic children. Material and methods: Thirty four hemophilic children aged 5 to 13 years were studied. A translation of the special survey to assess mental health in children, denominated "Domingo" Mental Health Survey was applied. It consisted in animated cartoon questions related to the family, social and school life. According to the score obtained, children were classified as normal, doubtful or pathologic. The social functioning areas studied were family, school, relationship and emotional. Aggressiveness, depression/anxiety and rejection were the psychopathologic factors analyzed. Results: Forty four percent of hemophilic children were considered normal, 20% doubtful and 35% pathologic. According to the severity of the disease, 67% of children with severe, 57% with moderate and 45% with mild hemophilia, were considered abnormal. Aggressiveness was the main risk factor in the emotional and family area, depression/anxiety in the family and emotional area and rejection in the family area. Fifty six percent of children had abnormalities in their social functioning and the severity of the disease was a predisposing factor. Conclusions: Psychopathologic factors in children with hemophilia appear mainly in the family environment.

Changes in blood presure in children undergoing psychological treatment before dental procedures

El objetivo de este trabajo fue determinar los cambios de la presión sanguínea (sistólica-diastólica) en niños que reciben tratamiento psicológico previo a la realización de un procedimiento odontológico. La población estudiada estuvo conformada por 100 niños y adolescentes en edades comprendidas entre los 6 y 15 años. Los pacientes fueron asignados al azar en dos grupos: con o sin tratamiento psicológico previo. En cuanto a la variable terapia psicológica, se aplicó la técnica conductual decir-mostrar-hacer. Las presiones sistólica y diastólica fueron evaluadas antes y durante el procedimiento clínico y después de darle de alta al paciente. El grupo que no recibió terapia psicológica mostró diferencias significativas en la presión diastólica y sistólica durante el tratamiento, a diferencia del otro grupo que no mostró variaciones significativas. Asimismo, no se encontró correlación entre las alteraciones de la presión sanguínea y el tipo de tratamiento recibido. Los resultados sugieren que la técnica decir-mostrar-hacer podría tener un efecto moderador sobre la presión sanguínea en pacientes que reciben tratamiento odontológico

Changes in blood presure in children undergoing psychological treatment before dental procedures

El objetivo de este trabajo fue determinar los cambios de la presión sanguínea (sistólica-diastólica) en niños que reciben tratamiento psicológico previo a la realización de un procedimiento odontológico. La población estudiada estuvo conformada por 100 niños y adolescentes en edades comprendidas entre los 6 y 15 años. Los pacientes fueron asignados al azar en dos grupos: con o sin tratamiento psicológico previo. En cuanto a la variable terapia psicológica, se aplicó la técnica conductual decir-mostrar-hacer. Las presiones sistólica y diastólica fueron evaluadas antes y durante el procedimiento clínico y después de darle de alta al paciente. El grupo que no recibió terapia psicológica mostró diferencias significativas en la presión diastólica y sistólica durante el tratamiento, a diferencia del otro grupo que no mostró variaciones significativas. Asimismo, no se encontró correlación entre las alteraciones de la presión sanguínea y el tipo de tratamiento recibido. Los resultados sugieren que la técnica decir-mostrar-hacer podría tener un efecto moderador sobre la presión sanguínea en pacientes que reciben tratamiento odontológico (AU)

Changes in blood presure in children undergoing psychological treatment before dental procedures

El objetivo de este trabajo fue determinar los cambios de la presión sanguínea (sistólica-diastólica) en niños que reciben tratamiento psicológico previo a la realización de un procedimiento odontológico. La población estudiada estuvo conformada por 100 niños y adolescentes en edades comprendidas entre los 6 y 15 años. Los pacientes fueron asignados al azar en dos grupos: con o sin tratamiento psicológico previo. En cuanto a la variable terapia psicológica, se aplicó la técnica conductual decir-mostrar-hacer. Las presiones sistólica y diastólica fueron evaluadas antes y durante el procedimiento clínico y después de darle de alta al paciente. El grupo que no recibió terapia psicológica mostró diferencias significativas en la presión diastólica y sistólica durante el tratamiento, a diferencia del otro grupo que no mostró variaciones significativas. Asimismo, no se encontró correlación entre las alteraciones de la presión sanguínea y el tipo de tratamiento recibido. Los resultados sugieren que la técnica decir-mostrar-hacer podría tener un efecto moderador sobre la presión sanguínea en pacientes que reciben tratamiento odontológico (AU)

[Homocysteinemia and its relationship with the methylentetrahydrofolate reductase polymorphism in various ethnic groups from western Venezuela]. / La homocisteinemia y su relación con el polimorfismo de la metilentetrahidrofolato reductasa en varios grupos etnicos del occidente de Venezuela.

The prevalence of hyperhomocysteinemia and C677T MTHFR polymorphism was studied in various ethnic groups from Western Venezuela (60 Wayuu Indians, 42 italian immigrants and 77 Venezuelan mestizos) in relation with the prevalence of hyperhomocysteinemia and the C677T MTHFR polymorphism. Homocysteinemia was determined by polarized fluorescence immunoassay in an IMX system, serum folate was measured by radioimmunoanalysis and the MTHFR genotype was determined by PCR and restriction analysis. Hyperhomocysteinemia was defined as a value over 2 SD above the mean value for normal MTHFR (CC677) in each group. The prevalence of MTHFR variants (C677T and 677TT) was elevated in all ethnic groups (78% among the wayuu, 76% among Italians and 63% among mestizos) with a significant association between the concentrations of homocysteine and the levels of serum folate among the wayuu (p < 0.0001) and the mestizos (p < 0.001) only. Hyperhomocysteinemia was associated with MTHFR variants in 23% of the wayuu (OR: 6.17, CI 95: 0.74-51.36), 9.5% of the Italians (OR: 0.93, CI 95: 0.085-10.10) and 20.7 of the Venezuelans mestizos (OR: 5.2, CI 95: 1.08-24.90, p > 0.03). There was no relationship between hyperhomocysteinemia and folate deficiency in any of the groups studied. In conclusion, despite a high prevalence of C677T MTHFR variants in these ethnic groups of western Venezuela, the lack of no evidence of hyperhomocysteinemia combined with folate deficiency may imply that the nutritional status of these groups plays an important role in the control of hyperhomocysteinemia as a risk factor for cardiovascular disease.

[Plasma homocysteine concentration and its relationship with the development of preeclampsia. Effect of prenatal administration of folic acid]. / Concentraciones de homocisteína plasmática en embarazadas y su relación con el desarrollo de preeclampsia. Efecto de la administración prenatal de ácido fólico.

The increase of plasmatic homocysteine (Hc) in pregnant women, who later develop preeclampsia/eclampsia, the cause of this increment and its pathogenic role in toxemia of pregnancy, are still controversial. The objectives of the present research were to determine the plasmatic He concentrations during the first and second trimesters of pregnancy and the effect of folic acid administration on these values, and in the prevention of preeclampsia. Ninety six pregnant women of low economic background were studied on the first prenatal consultation: 27 women in the first trimester of pregnancy and 59 in the second. After 8 hours of fasting, venous blood was extracted and each patient was provided with 1 mg folic acid tablets and instructed to ingest one tablet daily, and to come back to the laboratory after three months. Plasma homocysteine and serum folic acid were determined for each patient before and after the folic acid treatment, by using the IMX system (Abbott Lab) and radioimmunoassay, respectively. Basal homocysteine concentrations were 4.0 +/- 2.1 micromol/L and 4.8 +/- 2.1 micromol/L in the first and second trimesters respectively, with no significant modifications after three months of folic acid. Although the degree of desertion from the study was high, it was possible to determine the evolution of 65 pregnancies. Ten of them developed preeclampsia (15.4%). No significant differences were found in Hc concentrations, or the frequency of hyperhomocysteinemia in the different stages of pregnancy, between women with normal gestation and those who developed preeclampsia. The small sample size of these groups, preclude any valid conclusion, however the results do not suggest that Hc concentration or folic acid administration influence the development of toxemia of pregnancy.

Concentraciones de homocisteína plasmática en embarazadas y su relación con el desarrollo de preeclampsia: efecto de la administración prenatal de ácido fólico / Plasma homocysteine concentration and its relationship with the development of preeclampsia: effect of prenatal administration of folic acid

El aumento de la homocisteína en el plasma de las embarazadas que desarrollan preeclampsia/eclampsia, la razón de este aumento y su posible papel etiopatogénico en la toxemia del embarazo son objeto de controversia. Con la finalidad de conocer las concentraciones de homocisteína plasmática, en el primer y segundo trimestres del embarazo y el efecto que la administración de ácido fólico pudiera ejercer sobre ellas y en la prevención de preeclampsia, se estudiaron 96 mujeres embarazadas de bajos recursos económicos, que acudieron por primera vez a la consulta prenatal en el primer o segundo trimestres de gestación. Después de la extracción de sangre venosa en ayunas, a cada paciente se le entregaron comprimidos de 1 mg de ácido fólico con la instrucción de tomar uno diario y someterse a la extracción de sangre cada tres meses. En cada muestra se determinaron las concentraciones de homocisteína en plasma citratado, mediante el sistema IMX (Abbott Laboratories) y las de ácido fólico del suero, mediante radioinmunoanálisis (Diagnostic Products). La concentración de homocisteína basal fue de 4,0 ± 2,1 µmol/L en las embarazadas en el primer trimestre y 4,8 ± 2,1 µmol/L en las del segundo (p = N.S.), sin que estos valores se modificaran significativamente después de recibir ácido fólico. Un alto número de pacientes no cumplió con el estudio trimestral, sin embargo se conoció la evolución de 65 de ellas, 10 (15,4 por ciento) de las cuales desarrollaron preeclampsia. No se encontraron diferencias significativas entre las concentraciones de homocisteína ni entre la frecuencia de hiperhomocisteinemia entre las mujeres con embarazo normal y las que desarrollaron preeclampsia. Se concluye que las concentraciones de homocisteína plasmática, no variaron con la edad del embarazo ni con la administración de ácido fólico y que este último no influenció la aparición de preeclampsia en la población estudiada