Resumen La participación de los padres en la educación de sus niños es establecida como beneficiosa. Sin embargo, la clase social de la familia tiene una fuerte influencia sobre la eficacia de su ayuda con las tareas. En un estudio de caso comparativo, una familia inmigrante de México, de bajos ingresos, y una familia de Los Ángeles, de medianos ingresos, fueron observadas ayudando a sus niñas con deberes en matemáticas. Además, el investigador hizo preguntas sobre metas, estrategias de enseñanza y creencias sobre el aprendizaje. El análisis cualitativo se centró en dos métodos efectivos de enseñanza: proporcionar el aprendizaje de manera de andamio y estimular la lucha productiva. La madre de ingresos bajos proporcionó apoyo directo a su hija en lugar de proporcionar un andamio, y ella desaprobó los problemas difíciles; sin embargo, una hermana mayor con más educación que la madre proporcionó un andamio y creyó que los problemas difíciles ayudan al aprendizaje. En estos aspectos, la hermana mayor era similar a la madre de ingresos medios con educación universitaria. La hermana demuestra cómo hermanos mayores en las familias inmigrantes proporcionan puentes al éxito educativo para los hermanos menores. Sugerimos modos efectivos para que las escuelas puedan alentar a los padres con falta de oportunidades educativas a participar en la educación de sus hijos.

Abstract Parental involvement in children's education is commonly accepted as beneficial. However, family social class plays a crucial role in the efficacy of homework help. In a comparative case study, a low-income immigrant family from Mexico and a middle-income family in Los Angeles were observed helping their children with math homework and were asked questions about goals, tutoring strategies, and beliefs about learning. Qualitative analysis focused on two effective teaching methods: scaffolding and productive struggle. The low-income mother with little formal education provided direct help rather than a scaffold, and disapproved of hard problems. However, an older sibling with more education than her mother used scaffolding and believed that difficult problems aid learning. In these respects, she resembled the college-educated middle-income mother. The sister exemplifies how older siblings in immigrant families provide bridges to educational achievement for younger siblings. We suggest effective ways for schools to involve parents who lacked educational opportunity themselves to participate in the education of their children.

RESUMO O presente trabalho avaliou o papel do baço no armazenamento e na reativação das linhagens de células B, representadas por células IgM positivas imunomarcadas no tecido esplênico, bem como a funcionalidade dessas células, sobre a cinética dos linfócitos e na produção sistêmica de anticorpos em tilápias-do-nilo (Oreochromis niloticus). Foram separados dois grupos: grupo memória, constituído por peixes previamente imunizados com hemácia de carneiro a 2,5%, para a geração da memória imune, e o grupo naive, que recebeu o mesmo volume de solução salina a 0,65%. Após 32 dias, os dois grupos foram submetidos a uma nova dose do antígeno na mesma concentração, volume e via de inoculação. A reativação dos clones de memória foi evidenciada pelo aumento do número de células IgM positivas no baço do grupo memória no dia zero/pré-imune. Além disso, o mesmo grupo apresentou aumento dos títulos de anticorpos séricos no 14º dia e no número absoluto de linfócitos no 21º dia em relação ao grupo naive. Esses resultados sugerem que o baço não seja apenas um local de armazenamento, mas também de reativação de células B de memória em tilápia-do-nilo.

ABSTRACT This work aimed to evaluate the role of the spleen in storage and reactivation of the memory B cells, represented by IgM positive cells and the systemic production of sheep antibodies anti-red cell in Nile tilapia (Oreochromis niloticus). Two groups were established: the memory group, containing fish previously immunized with a 2,5% sheep anti-red cell, to generate the immune memory; and the naive group, containing fish that received a 0,65% saline solution. After 32 days, both groups were subjected to a new dose of the same antigen at the same concentration, volume, and inoculation via. The memory clones reactivation was correlated to the increase of the IgM positive cells in the spleen in the memory group at 0 day. The memory group showed an increase in the absolute number of lymphocytes at 21 days and an increase in the antibodies at 14 days after inoculation when compared to the naive group. The results suggest that the spleen may be a storage and reactivation place of memory B cells in Nile tilapia.

A bactéria Streptococcus agalactiae é um potente agente causador de surtos por doenças bacterianas em peixes. O estresse provocado pelo manejo zootécnico e pela má qualidade ambiental torna a tilápia susceptível às infecções por essa bactéria. O objetivo do presente trabalho foi avaliar a resistência de tilápias-do-nilo imunizadas com soro hiperimune anti-S. agalactiae, posteriormente desafiadas com cepa homóloga da mesma bactéria. Após determinação da DL 50 de S. agalactiae, 36 tilápias foram distribuídas em quatro aquários, dois para o grupo controle e dois para inoculação celomática para produção de anticorpos anti-S. agalactiae. No 21° e 28° dias, foi coletado sangue para obtenção de soro hiperimune utilizado na transferência passiva. Em seguida, 30 tilápias foram distribuídas em três aquários e submetidas a três tratamentos: GI: controle; GII: imunizadas com o soro inativado; GIII: imunizadas com soro ativo. Após 48 horas e sete, 14, 21, 28 e 35 dias, foram realizadas coletas de sangue para titulação de anticorpos anti-S. agalactiae utilizando-se o teste de aglutinação direta. Para avaliar a taxa de sobrevivência, outras 30 tilápias foram distribuídas em três aquários e submetidas a três tratamentos (GI: controle; GII: imunizadas com soro inativado; GIII: imunizadas com soro ativo). Após 48 horas da imunização, as tilápias foram desafiadas via celomática com 100µL de S. agalactiae e avaliadas duas vezes ao dia, pelo período de 35 dias. Os resultados dos títulos séricos de anticorpos foram detectados pela aglutinação direta até o 21° dia pós-transferência passiva, e, no mesmo período, houve proteção de 80% entre os grupos imunizados com soro inativado e soro ativo contendo anticorpos anti-S. agalactiae. Ao final, os grupos soro inativado e soro ativo apresentaram 60 e 80% de proteção, respectivamente, enquanto no grupo controle 100% dos peixes adoeceram, apresentando sinais graves da infecção, e foram eutanasiados. Não houve diferença estatística significativa na taxa de proteção entre os grupos imunizados.

The Streptococcus agalactiae bacteria is a potent agent which causes outbreaks of bacterial diseases in fish. The stress caused by management and poor environmental quality makes tilapia susceptible to infections, including by bacterium. The aim of this study was to evaluate the resistance of the Nile tilapia immunized with hyperimmune serum against S. agalactiae subsequently challenged with homologous strain of the same bacteria. After determining the DL 50 of S. agalactiae, 36 tilapias were distributed in 4 aquariums, 2 for the control group and 2 for the group via coelomic, inoculated with the DL 50 for anti-S. agalactiae antibodies production. On the 21st and 28th day blood was collected for the obtainment of hiperimmune serum used in passive transference. Then, 30 tilapias were distributed in 3 aquariums submitted to 3 treatments (GI: control; GII: immunized with inactivated-serum; GIII: immunized with non-inactivated serum). After 48 hours, 7, 14, 21, 28 and 35 days blood collections were done for anti-S. agalactiae antibodies titration using the direct agglutination test. For survival evaluation 30 tilapias were distributed in 3 aquariums and submitted to 3 treatments (GI: control; GII: immunized with inactivated-serum; GIII: immunized with non-inactivated serum). After 48 hours of inoculation tilapias were challenged with 100µL of S. agalactiae and monitored twice a day for 35 days. The results showed that titers of antibodies were detected by direct agglutination until the 21st day after passive transference and during the same period the protection between the groups immunized with inactivated serum and non-inactivated serum contending anti-S. agalactiae antibodies was of 80% after challenge with S. agalactiae. In the end, the serum-inactivated serum and active groups had 60 and 80% protection, respectively, while 100% of the fish in the control group developed severe signs of infection and were euthanized. There was no statistical difference in the survival rate between the immunized groups.

We are reporting a study of the response of a biological tissue with a malignant melanoma induced of the cell line MEL-RC08 by means of Biospeckle’s technique. The study was performed on four prepared samples, which were placed in plastic wells prepared for such purposes. The used samples were: RPMI-1640 Gel; RPMI1640 plus 10(5) cells of the cell line MEL − RC08, and the other two plastic wells was added a concentration of 1 mg and 2 mg of Colcemid drug, respectively. The samples were tested at the same time by analyzing the temporal evolution of speckle patterns in each of them. For that, we designed an experiment, which consisted of to illuminate the samples with an He-Ne laser and acquire a set of 96 images for 24 hours by using a high resolution camera. Next, a temporal difference method for processing dynamic speckle patterns was implemented with the aim of analyzing the biological activity. The obtained results show that exist a change in the behavior of the biological activity of the samples depending on concentration of the applied drug. The advantages and disadvantages of the method are discussed.

Se presenta un estudio de la actividad biológica de células de un melanoma de piel ante la presencia de diferentes concentraciones del medicamento Colcemid mediante la técnica de Biospeckle. El estudio fue realizado sobre cuatro muestras colocadas en pocillos plásticos preparados para tales fines. Las muestras fueron: el medio de cultivo RPMI-1640 Gel; el medio de cultivo con 10(5) células de la línea MEL − RC08 y lo anterior con 1 µg y 2 µg de medicamento Colcemid, respetivamente. Estas muestras fueron estudiadas a la vez, mediante la técnica de Biospeckle que consiste en analizar la evolución temporal de los patrones de speckle de las mismas. Para esto, se diseño un experimento que consiste en iluminar las muestras con un haz de luz láser de He-Ne y adquirir un conjunto de 96 imágenes durante 24 horas usando una cámara de alta resolución Firewire. Las imágenes adquiridas son procesadas usando el método de las diferencias temporales de patrones de speckle para analizar su actividad biológica. Los resultados obtenidos muestran cambios en el comportamiento de la actividad biológica de las muestras en dependencia de la concentración de medicamento aplicada. Se discuten también las ventajas y desventajas del método empleado.

OBJECTIVES: 1) To characterize the impact of multiple myeloma on the quality of life of patients treated in two public institutions in São Paulo State, Brazil, using a generic Short Form 36 Health Survey and a questionnaire specific for oncologic patients (QLQ-C30) upon diagnosis, after the clinical treatment, and at day +100 after autologous stem cell transplantation; 2) to evaluate whether autologous stem cell transplantation can improve the quality of life of our economically challenged population aside from providing a clinical benefit and disease control. METHODS: We evaluated 49 patients with multiple myeloma (a total of 70 interviews) using the two questionnaires. The scores upon diagnosis, post-treatment/pre-autologous stem cell transplantation, and at D+100 were compared using ANOVA (a comparison of the three groups), post hoc tests (two-by-two comparisons of the three groups), and paired t-tests (the same case at two different times). RESULTS: Of the included patients, 87.8% had a family budget under US $600 (economic class C, D, or E) per month. The generic Short Form 36 Health Survey questionnaire demonstrated that physical function, role-physical, and bodily pain indices were statistically different across all three groups, favoring the D+100 autologous stem cell transplantation group (ANOVA). The questionnaire specific for oncologic patients, the QLQ-C30 questionnaire, confirmed what had been demonstrated by the Short Form 36 Health Survey with respect to physical function and bodily pain, with improvements in role functioning, fatigue, and lack of appetite and constipation, favoring the D+100 autologous stem cell transplant group (ANOVA). The post hoc tests and paired t-tests confirmed a better outcome after autologous stem cell transplantation CONCLUSION: The questionnaire specific for cancer patients seems to be more informative than the generic Short Form 36 Health Survey questionnaire and reflects the real benefit of autologous stem cell transplantation in the quality of life of multiple myeloma patients in two public Brazilian institutions that provide assistance for economically challenged patients.

An analytical prospective and observational study was conducted in closed institutions of Havana City during an epidemic outbreak of acute viral hepatitis from March 2005 to January 2006. The data source was obtained from the surveillance system of the Hygiene and Epidemiology Territorial Unit. In the epidemic conglomerates, it was estimated the vulnerability rate as a probable expression of risk and it was also verified its correspondence with the morbidity impact. Risk indicators were calculated, which showed that group 1 had the greatest number of vulnerable factor and, hence, the highest expected rate with 8.05 per 1 000 inhabitants. The factor representing more risks for acquiring acute viral hepatitis were the poor quality of water (90 %), an insufficient water supply, and the inadequate health facilities for hand washing (88 %). On the other hand, Arroyo Naranjo municipality had a relative risk of 2.75, beign the area with the greatest impact of environmental risks. It was found a relationship between vulnerable factors and morbidity from acute viral hepatitis, since the units with the greatest accumulation of factors presented the highest rates. In general, there were no significant differences between the observed and the expected rates. It was proved the importance of the quality of water, of the health facilities for hand washing, and of an adequate water supply, among others, to prevent acute viral hepatitis, since these factors are a big risk for acquiring this disease.

Se realizó un estudio observacional analítico de tipo prospectivo en instituciones cerradas de Ciudad de La Habana durante un brote epidémico de hepatitis viral aguda en el período comprendido desde marzo de 2005 a enero de 2006. La fuente de datos se obtuvo del sistema de vigilancia de la Unidad Territorial de Higiene y Epidemiología. En los conglomerados epidémicos se estimó el índice de vulnerabilidad como expresión probabilística de riesgo y se comprobó su correspondencia con las áreas de impacto de la morbilidad. Se calcularon los indicadores de riesgo, los cuales reflejaron que la agrupación 1 presentó el mayor acumulado de factores vulnerables, y por tanto, la mayor tasa esperada con 8,05 por cada 1 000 habitantes. Los factores que aportaron más riesgo de contraer hepatitis viral aguda fueron la mala calidad sanitaria del agua (90 %), el insuficiente suministro de esta y las inadecuadas facilidades sanitarias para el lavado de manos, (88 %). Por otro lado, el municipio Arroyo Naranjo presentó un riesgo relativo de 2,75, por lo que fue el área de mayor impacto de riesgos ambientales. Se observó asociación entre los factores vulnerables y la morbilidad por hepatitis viral aguda, ya que las unidades con mayor acumulado de factores fueron las que presentaron mayores tasas. De manera general, no hubo diferencias significativas entre las tasas observadas y esperadas, lo cual refleja la buena capacidad de discriminación del método. Se demostró la importancia de la calidad sanitaria del agua, las facilidades sanitarias para el lavado de manos y el suficiente suministro de agua entre otros, en la prevención de la hepatitis viral aguda, factores estos que más aportaron al riesgo de contraer dicha enfermedad.

A cohort, prospective and longitudinal clinicoepidemiological research was conducted to evaluate the influence of various coronary risk factors in the clinical control of arterial hypertension from November 2000 to January 2002. The population studied was composed of 120 military officers that were diagnosed essential arterial hypertension and categorized at their family physician's office. 2 study groups were organized: one exposed (n=60) with cardiovascular disease risk factors, and a non-exposed group (n=60) of hypertensive patients without other concomitant risks. Both groups were simultaneously observed for a year with monthly readings to compare the control of arterial pressure. The results obtained reported that the cardiovascular risk factors associated with hypertension were sedentarism, obesity, stress, smoking, hyperlipidaemia and diabetes mellitus. The behavior according to the criteria of control showed that the incidence rate/100 individuals of the uncontrolled was higher in the exposed group (56.2/100 individuals) in relation to the nonexposed (20.0/100 individuals) with a relative risk of 2.81, which confirmed the hypothesis of causal association between both variables. The association of other cardiovascular risk factors with arterial hypertension influences on the clinical control of arterial pressure and on its natural evolution, since it significantly increases the probability of severe cardiovascular events that justify the elevated morbidity and mortality.

Se realizó una investigación clínico-epidemiológica, de cohorte, prospectiva y longitudinal para evaluar la influencia de varios factores de riesgo coronario en el control clínico de la hipertensión arterial. La investigación abarcó el período comprendido entre noviembre de 2000 hasta enero de 2002. La población objeto de estudio estuvo integrada por 120 oficiales diagnosticados de hipertensión arterial esencial y dispensarizados en su puesto médico de salud. Se conformaron 2 grupos de estudio: uno expuesto (n=60) con factores de riesgo de enfermedad cardiovascular y un grupo no expuesto (n=60) de pacientes hipertensos, pero sin otros riesgos concomitantes. Se observaron ambos grupos simultáneamente durante un año, con tomas mensuales para comparar el control de la tensión arterial. Los resultados obtenidos reportan que los factores de riesgo cardiovascular asociados con la hipertensión fueron el sedentarismo, la obesidad, el estrés, el tabaquismo, la hiperlipidemia y la diabetes mellitus. El comportamiento según criterios de control muestra que la tasa de incidencia/100 efectivos de los no controlados fue mayor en el grupo expuesto (56,2/100 efectivos) en relación con el grupo no expuesto (20,0/100 efectivos), con un riesgo relativo de 2,81, lo que confirmó la hipótesis de asociación causal entre ambas variables. La asociación de otros factores de riesgo cardiovascular a la hipertensión arterial influye en el control clínico de la tensión arterial y en su evolución natural, ya que incrementa sustancialmente la probabilidad de eventos cardiovasculares graves que justifican la elevada morbilidad y mortalidad.

Chronic heart failure is a clinical syndrome that appears lately in the natural evolution of different heart diseases. At present, multiple pathogenic mechanisms that have a prognostic importance and influence on their therapeutical management are recognized. The activation of a series of neurohormonal systems, such as the sympathetic nervous system and the renin-angiotensin-aldosterone system stand out among these mechanisms They participate in the perpetuation and progression of the disease and shadow the clinical evolution if they are not modulated or inhibited. The deleterious effects of these neurohormonal systems on the anatomy and cardiovascular function and the authentic vicious circle they generate are dealt with. They lead to an irreversible heart failure and to the increase of morbidity and mortality. The benefits of the drugs acting on these systems are also analyzed.

La insuficiencia cardiaca crónica es un síndrome clínico que aparece tardíamente en la evolución natural de distintas enfermedades cardiacas. Reconoce en la actualidad múltiples mecanismos patogénicos los cuales tienen importancia pronóstica e influyen en su manejo terapéutico. Entre estos mecanismos resaltan la activación de una serie de sistemas neurohormonales como: el sistema nervioso simpático y el sistema renina-angiotensina-aldosterona; estos participan en la perpetuación y progresión de la enfermedad, y ensombrecen la evolución clínica si no son modulados o inhibidos. Se exponen los efectos deletéreos de estos sistemas neurohumorales sobre la anatomía y función cardiovascular y el auténtico círculo vicioso que generan y conducen al fallo cardiaco irreversible y al incremento de la morbilidad y mortalidad, además de analizar los beneficios de fármacos que actúan sobre dichos sistemas.

OBJETIVO: Avaliar a precisão das doses de radiação absorvidas na terapia de transplantes de medula óssea durante a técnica de irradiação de corpo inteiro. MATERIAIS E MÉTODOS: Utilizaram-se 200 pastilhas de sulfato de cálcio com disprósio compactado com teflon (CaSO4 + teflon), calibradas no ar e no "phantom", selecionadas aleatoriamente e dispostas em grupos de cinco no corpo dos pacientes. As leituras dosimétricas foram efetuadas pela leitora Harshaw 4000A. Nove pacientes foram irradiados no corpo inteiro em paralelos e em opostos laterais, utilizando-se unidade de cobalto-60, modelo Alcion II, com taxa de dose de 0,80 Gy/min a 80,5 cm, {campo (10 × 10) cm²}. A dosimetria dessa unidade foi realizada com dosímetro Victoreen 500. Para a determinação da dose média em cada ponto avaliado usaram-se os fatores individuais de calibração das pastilhas no ar e no "phantom", colocando-se um "build up" de 2 mm para superficializar a dose à distância de 300 cm. RESULTADOS: Em 70% dos pacientes obteve-se variação de dose menor que 5% e em 30% dos pacientes essa variação foi inferior a 10%, quando comparados os valores medidos com aqueles calculados em cada ponto. Na cabeça ocorre absorção, em média, de 14% da dose administrada, e nos pulmões, acréscimo de 2% na dose administrada. Nos pacientes com distância látero-lateral maior que 35 cm as variações entre as doses calculadas e medidas podem chegar a 30% da dose desejada, sem o uso de filtros compensadores. CONCLUSÃO: Os valores medidos das doses absorvidas nos diversos pontos anatômicos, comparados aos valores desejados (teóricos), apresentam tolerância de ±10%, considerando-se as diferenças anatômicas existentes, quando utilizados os fatores de calibração individuais das pastilhas.

OBJECTIVE: To evaluate the precision of the absorbed radiation doses in bone marrow transplant therapy during whole body irradiation. MATERIALS AND METHODS: Two-hundred CaSO4:Dy + teflon tablets were calibrated in air and in "phantom". These tablets were randomly selected and divided in groups of five in the patients' body. The dosimetric readings were obtained using a Harshaw 4000A reader. Nine patients had their entire bodies irradiated in parallel and opposite laterals in a cobalt-60 Alcion II model, with a dose rate of 0.80 Gy/min at 80.5 cm, {(10 × 10) cm² field}. The dosimetry of this unit was performed using a Victoreen 500 dosimeter. For the determination of the mean dose at each point evaluated, the individual values of the tablets calibrated in air or "phantom" were used, resulting in a build up of 2 mm to superficialize the dose at a distance of 300 cm. RESULTS: In 70% of the patients a variation of less than 5% in the dose was obtained. In 30% of the patients this variation was less than 10%, when values obtained were compared to the values calculated at each point. A mean absorption of 14% was seen in the head, and an increase of 2% of the administered dose was seen in the lungs. In patients with latero-lateral distance greater than 35 cm the variation between the calculated doses and the measured doses reached 30% of the desired dose, without the use of compensation filters. CONCLUSION: The measured values of the absorbed doses at the various anatomic points compared to the desired doses (theoretic) presented a tolerance of ± 10%, considering the existent anatomical differences and when using the individual calibration factors of the tablets.

A review of all the information obtained from the information sources known in Medicine (Medline, Index Medicus, Cochrane Collaboration and other physcial, electronic and virtual libraries) about the new biochemical and imaging markers, whose prognostic usefulness has been proved in the stratification of the cardiovascular risk in the acute atherosclerotic coronary artery disease, was made by using the methodology systematicness for evaluating scientific evidence. Afterwards, the information collected was critically analyzed according to the recommendations of the guides for the evaluation by levels of the reference literature, making a conscious, reasoned and explicit use of the best evidence available for the decision-making in the care of individual patients with this entity. It was part of the best individual clinical experience obtained in a systematic search.

Se realizó con la utilización de la sistemática de la metodología para la evaluación de la evidencia científica, una revisión de toda la información obtenida de las fuentes de información conocidas en medicina (Medline, Index Medicus, Cochrane colaboration y otras bibliotecas físicas, electrónicas y virtuales), acerca de los novedosos marcadores bioquímicos e imagenológicos que tienen utilidad pronóstica comprobada en la estratificación del riesgo cardiovascular en la enfermedad coronaria aterosclerótica aguda. Posteriormente, se analizó de forma crítica la información obtenida según las recomendaciones de las guías para la evaluación en niveles de la literatura referenciada haciendo un uso consciente, razonado y explícito de la mejor evidencia disponible para la toma de decisiones en el cuidado de pacientes individuales con esta entidad e integró la mejor experiencia clínica individual obtenida en una búsqueda sistemática.

An observational and analytical case-control study was made to set the influence of the smoking risk gradient on the clinical control of blood hypertension as a potential determining atherogenic association in the clinical evolution of atherosclerotic cardiovascular disease. The inclusion criteria took into consideration smoking persons with confirmed diagnosis of essential blood hypertension, aged 15-60 years regardless of race or sex, and detected in the year 2002 at primary health care. Hypertensives with other concomitant coronary risks, and those who did not attend regularly to medical appointments for their classification or refused to participate in the research were all excluded. Smoking gradient was set in relation to the number of cigarettes daily consumed, so smokers were broken down as light (1-9 cigarettes/day); moderate (10-15 cigarettes/day) and heavy (over 15 per day). Eighty nine patients, 78 males (87,6 %) and 11 females (12,4 %), were studied of whom 28 (31,4 %) were slight, 37 (41,6 %) moderate and 24 (27 %) heavy smokers. 60,6 % (54 cases) were Caucasian whereas 39,4 % (35 cases) were Black. The prevalence of the clinical control of hypertension was 100 % among light smokers; however it was very low in moderate and heavy smokers (2,7/100) and (0/100) respectively, so lack of control was significantly remarkable. A substantial rise in blood pressure accompanies the act of smoking a cigarette and those that continue smoking will not receive the total protection that antihypertensive therapy provides against atherosclerotic cardiovascular disease. Therefore, it is fundamental to avoid smoking in any of its variants and in all age groups.

An observational and descriptive cross-sectional study was conducted from January to December, 2002, aimed at evaluating the usefulness of the body mass index (BMI) to identify the population with the highest personal atherogenic attribute and the influence of overweight-obesity on the clinical control of arterial hypertension. 150 hypertensive patients from the basic health care level were studied. According to the BMI, they were classified into normoweight, overweight and obese. Variables such as age, sex complexion, systolic and diastolic arterial pressure and pharmacological treatment were studied. The incidence of clinical decontrol of arterial hypertension according to BMI and age groups, showed that the clinical decontrol of arterial hypertension behaved in a similar way in the overweight (60.8 %) and in the obese (58.6 %). The highest magnitude was observed in the 50-59 age group (80.8 %). The estimation of the association force between overweight - obesity and the clinical decontrol of arterial hypertension showed 1.6 times more probability of decompensation in patients over the ideal weight according to height than in the normoweight with an attributable percent risk. It is estimated that 34 % of the patients with clinical decontrol may be prevented if this causal factor is eliminated. The BMI is useful as an anthropometric indicator of the atherogenic damage risk and it has a strategical importance in health surveillance at the primary health care level.

Se realizó un estudio observacional descriptivo de sección transversal durante el período comprendido de enero a diciembre de 2002 para evaluar la utilidad del índice de masa corporal (IMC), a fin de identificar a la población con mayor atributo personal aterogénico y la influencia del sobrepeso-obesidad en el control clínico de la hipertensión arterial. El universo de estudio estuvo constituido por 150 pacientes hipertensos dispensarizados en el nivel de atención médica básica, los cuales de acuerdo con el IMC fueron clasificados en normopeso, sobrepeso y obesos. Se estudiaron variables como edad, sexo, color de la piel, tensión arterial sistólica y diastólica y el tipo de tratamiento farmacológico. La incidencia del descontrol clínico de la hipertensión arterial según el IMC y grupos de edad mostró que el mayor número de descontrol clínico de la hipertensión arterial se ubicó de forma similar en los grupos sobrepeso (60,8 %) y obesos ( 58,6 %), con la mayor magnitud en el grupo de 50 a 59 años de edad (80,8 %), en los sobrepesos y a este mismo nivel los obesos (63,6 %). La estimación de la fuerza de asociación entre el sobrepeso-obesidad y el descontrol clínico de la hipertensión arterial mostraron 1,6 veces más probabilidad de descompensación en los pacientes por encima del peso ideal para la talla que los normopeso, con un riesgo atribuible porcentual estimando que el 34 % de los pacientes con descontrol clínico pueden evitarse si se elimina este factor causal. El IMC tiene utilidad como indicador antropométrico del riesgo de daño aterogénico y reviste importancia estratégica en la vigilancia de salud en la atención primaria.

At present, there are biochemical and molecular basis to think that the key of the problems connected with arterial hypertension, its clinical manifestations and complications is the loss of balance that should exist between preoxidation and antioxidation. There are increasing evidences about the participation of the oxidative stress in the pathogeny of the disease. The latest knowledge of oxidative stress and the clinical and physiopathological implications derived from its action, as well as the optimum therapeutic outlooks offered by the use of antihypertensive agents controlling or eliminating those factors that rise the vascular peripheral resistance, responsible for sustained arterial hypertension, and having an associated antioxidant action, are reviewed.

En la actualidad hay bases bioquímicas y moleculares para poder pensar que la clave de los problemas relacionados con la hipertensión arterial, sus manifestaciones clínicas y complicaciones está en la pérdida del equilibrio que debe mantenerse entre la prooxidación y antioxidación emergiendo crecientes evidencias de la participación del estrés oxidativo en la patogenia de la enfermedad. Se revisaron los últimos conocimientos sobre el estrés oxidativo y las implicaciones clínicas y fisiopatológicas derivadas de su acción, así como las perspectivas terapéuticas óptimas que ofrecen el empleo de agentes antihipertensivos que controlen o eliminen los factores que aumentan la resistencia vascular periférica, responsable de hipertensión arterial sostenida y que posean acción antioxidante asociada.

Thermal denaturation of Subtilisin BPN' was studied by circular dichroism. It was observed that the process was strongly dependent on the heating rate, as is expected for an unfolding process kinetically controlled due to presence of an irreversible reaction. Thermal unfolding process follows a simple two-state mechanism (N → D). The activation energy (E) to this reaction was calculated by different methods. The obtained values for E were rather than similar to one another, varying from 266 to 339 kJ mol-1.

Se estudió la desnaturalización térmica de la subtilisina BPN' por dicroísmo circular. Se observa que el proceso fue fuertemente dependiente de la velocidad de calentamiento, como es de esperarse para un proceso de desplegamiento que se encuentra bajo control cinético, debido a la presencia de una reacción irreversible. El proceso de desnaturalización térmica sigue un modelo simple de dos estados (N → D). Se calculó la energía de activación (E) para la reacción por diferentes métodos. El valor de E obtenido fue muy similar variando de 266 a 339 kJ mol-1.