Estatinas x ácido lipóico na prevenção e tratamento das doenças cardiovasculares / Statins x lipoic acid in the prevention and treatment of cardiovascular diseases

Cardiovascular diseases (CVD) are the leading cause of death worldwide and atherosclerosis is the most important process underlying CVD. Statins are widely used in primary and secondary prevention of CVD, though their adverse side effects, such as myopathy and hepatotoxicity, justify the search for therapeutic alternatives. Alpha lipoic acid is a potent antioxidantand its potential use to combat various conditions, such as diabetic nephropathy, metal poisoning, Alzheimer's disease and CVD has been under intense study. The aim of this review was to gather information on the use of statins and alpha lipoic acid in the prevention and treatment of CVD. The literature suggests that inaddition to the known side effects most associated with the use of statins, they can also cause reduced levels of coenzyme Q10 (CoQ10), an important mitochondrial antioxidant and electron transport chain carrier that has the capacity to antagonize oxidation of plasma lowdensity lipoprotein (LDL). The loss of CoQ10 can reduce adenosine triphosphate (ATP) levels in cardiac cells, further worsening the overall state of the individual. Alpha lipoic acid produces favorable metabolic and endothelial anti-inflammatory effects, without adverse side effects, and thus may be an alternative treatment for the prevention of CVD. However, more controlled clinical studies are needed to establish definitively the prophylactic and therapeutic potential of alpha lipoic acid and to decide whether it might be more effective than statins for the prevention and treatment of CVD...

As doenças cardiovasculares (DCVs) são a principal causa de morte no mundo e tem a aterosclerose como componente mais importante. As estatinas são extensamente utilizadas na prevenção primária e secundária das DCVs, todavia seus efeitos adversos como miopatia e toxicidade hepática justificam a busca por alternativas terapêuticas. O ácido lipóico é um potente antioxidante e vem sendo intensamente investigado no combate de diversas condições tais como nefropatia diabética, intoxicação por metais, doença de Alzheimer e nas DCVs. O objetivo desta revisão foi reunir informações acerca da utilização das estatinas e do ácido lipóico na prevenção e tratamento das DCVs. A literatura aponta que além dos efeitos adversos mais conhecidos associados ao uso das estatinas, elas também podem ocasionar a redução dos níveis de Coenzima Q10 (CoQ10), um importante antioxidante mitocondrial e transportador de elétrons, que possui a capacidade de antagonizar a oxidação da Lipoproteína de Baixa Densidade (LDL) plasmática. Ainda, a deficiência da CoQ10, por sua vez, pode levar a diminuição da adenosina trifosfato (ATP) nas células cardíacas, comprometendo ainda mais o estado global do indivíduo. Enquanto isso, o ácido lipóico apresenta favoráveis efeitos antiinflamatórios, metabólicos e endoteliais, contudo sem a presença de efeitos adversos, podendo ser uma opção terapêutica na prevenção das DCVs. Entretanto, mais estudos clínicos controlados são necessários para estabelecer de maneira definitiva os potenciais terapêuticos e profiláticos do ácido lipóico, avaliando se ele pode ser mais efetivo para a prevenção e tratamento das DCVs do que as estatinas...

Phytohemagglutinin improves the development and ultrastructure of in vitro-cultured goat (Capra hircus) preantral follicles

The objective this study was to determine the effect of phytohemagglutinin (PHA) on survival, growth and gene expression in caprine secondary follicles cultured in vitro. Secondary follicles (∼0.2 mm) were isolated from the cortex of caprine ovaries and cultured individually for 6 days in α-MEM+ supplemented with PHA (0, 1, 10, 50, 100, or 200 µg/mL). After 6 days of culture, follicle diameter and survival, antrum formation, ultrastructure and expression of mRNA for FSH receptors (FSH-R), proliferating cell nuclear antigen (PCNA), and neuronal nitric oxide synthase were determined. All treatments maintained follicular survival [α-MEM+ (94.59%); 1 µg/mL PHA (96.43%); 10 µg/mL PHA (84.85%); 50 µg/mL PHA (85.29%); 100 µg/mL PHA (88.57%), and 200 µg/mL PHA (87.50)], but the presence of 10 µg/mL PHA in the culture medium increased the antrum formation rate (21.21%) when compared with control (5.41%, P < 0.05) and ensured the maintenance of oocyte and granulosa cell ultrastructures after 6 days of culture. The expression of mRNA for FSH-R (2.7 ± 0.1) and PCNA (4.4 ± 0.2) was also significantly increased in follicles cultured with 10 µg/mL PHA in relation to those cultured in α-MEM+ (1.0 ± 0.1). In conclusion, supplementation of culture medium with 10 µg/mL PHA maintains the follicular viability and ultrastructure, and promotes the formation of antral cavity after 6 days of culture in vitro.

Calidad de la información sobre ejercicios en las páginas de Internet dirigida a sobrevivientes de cáncer de seno / Quality of the information on exercise found on websites aimed at breast cancer survivors

Objetivo. Describir la calidad de la información acerca de ejercicios en Internet dirigida a sobrevivientes de cáncer de seno. Método. El diseño del estudio es exploratorio descriptivo. Se evaluó la calidad de la información acerca de ejercicios en un total de 40 páginas de Internet: se utilizaron 3 instrumentos para evaluar la calidad de la información: Discern, InEje (calidad de la información de ejercicios) y FRES/Huertas. Resultados. Los porcentajes de los promedios obtenidos con respecto a la puntuación máxima posible para cada instrumento fueron: Discern 62,67%, InEje 15,23%, y FRES/Huertas 56,51%. Conclusión. La evidencia sugiere que es necesario mejorar la calidad de la información sobre ejercicios de las páginas de Internet en inglés y español para sobrevivientes de cáncer de seno (AU)

Goal: To analyze the changes produced by therapeutic massage on systemic autonomic activity by analyzing the modification of cardiac autonomic activity. Material and methods: A comparative study was performed on 15 women on the variability of heart rate variability (HRV) (RR interval) obtained by photoplethysmography for 2 20-minute sessions: control and massage. HRV was measured at 4 different times for periods of 5 minutes each. The massage session consisted of effleurage massage and wide-ranging sliding pressure. In addition, the participants had to fill out the well-being visual analogue scale (Well Being VAS) questionnaire immediately after the control and massage session. Results: The paired Student’s t-test was used to compare the results obtained. Pearson correlation coefficient was used to quantify the relationship existing between the different times in each one of the parameters. A statistically significant increase was observed in HRV (total power) as well as an increase in parasympathetic activity in the massage session during the last 5 minutes (relative to baseline) compared to control session. However, this response tends to decrease 5 minutes after its interruption/timeout. Finally, the Well Being VAS score shows a significant increase after the massage. However, its gain is not correlated to the changes in the physiological variables. Conclusions: The massage applied on healthy subjects affects the autonomic nervous system (AU)

Análise sobre a fitoterapia como prática integrativa no Sistema Único de Saúde / Analysis about phytotherapy as an integrating practice in the Brazilian Unified Health System (UHS)

É notável o crescente uso da fitoterapia como prática médica integrativa em diversos países. A utilização de plantas medicinais no Brasil tem como facilitadores a grande diversidade vegetal e o baixo custo associado à terapêutica, o que vem despertando a atenção dos programas de assistência à saúde e profissionais. O Ministério da Saúde, com a finalidade de evitar o uso inadequado desta prática medicinal, tem demonstrado interesse por meio do incentivo de pesquisas relacionadas ao assunto, favorecendo a implantação de programas de saúde visando à distribuição e utilização destes medicamentos de forma racional. Baseado neste contexto foi realizado levantamento de como esta temática vem sendo abordada e implementada no Sistema Único de Saúde (SUS). Trata-se de estudo descritivo com abordagem qualitativa, realizado através de levantamento bibliográfico em bases de dados relacionado ao tema "medicamentos fitoterápicos no sistema único de saúde". Os descritores utilizados durante toda a pesquisa foram fitoterapia, medicamentos fitoterápicos, medicina integrativa, medicamentos, medicina herbária, fitoterapia no SUS, medicina integrativa e sistemas públicos de saúde. Observou-se que o governo tem demonstrado interesse no desenvolvimento de políticas que associem o avanço tecnológico ao conhecimento popular em prol de procedimentos assistenciais em saúde que apresentem eficácia, abrangência, humanização e menor dependência com relação à indústria farmacêutica. Nas duas últimas décadas, alguns estados e municípios brasileiros vêm realizando a implantação de Programas de Fitoterapia na atenção primária à saúde, com o intuito de suprir as carências medicamentosas de suas comunidades. Apesar da crescente busca por integrativas medicamentosas, os estudos acerca da fitoterapia ainda são precários no Brasil, fazendo-se ainda necessárias pesquisas nesta área, de modo a ampliar o conhecimento dos profissionais e estudantes da saúde, auxiliando e tornando mais sólidas as bases de segurança e eficácia para implementação das praticas fitoterápicas no SUS.

The growing use of phytotherapy as an integrating medical practice in several countries has been remarkable. The use of medicinal plants in Brazil is facilitated by the plant diversity and low cost associated with therapeutics, which has called the attention of health assistance programs and professionals. The Brazilian Ministry of Health, in order to avoid misuse of this medical practice, has demonstrated interest, developing policies that encourage research related to this issue and favoring the establishment of health programs focused on the distribution and use of these drugs in a rational way. Based on this context, a survey about how this issue has been addressed and implemented in the Unified Health System (UHS) was carried out. This was a descriptive study of qualitative approach, performed through a literature review in databases, related to the theme "phytotherapic medicines in the unified health system". The key words used throughout the study were: phytotherapy, phytomedicines, integrating medicine, medicines, herbal medicine, phytotherapy in the UHS, integrating medicine and public health systems. The government has shown interest in developing policies which combine technological advances with common knowledge for the sake of assistance health procedures that show effectiveness, coverage, humanization and less dependence on the pharmaceutical industry. In the last two decades, some Brazilian states and municipalities have implemented Phytotherapy Programs in primary health care in order to meet the drug needs of their communities. Despite the growing search for integrating drugs, studies about phytotherapy are still limited in Brazil, with the need of research in this area in order to increase the knowledge of health professionals and students, helping and making more solid the safety and efficacy bases for the implementation of phytotherapic practices in the UHS.

Políticas públicas de medicamentos: trajetória e desafios / Public policies for medicines: trajectory and challenges

Por meio de um levantamento bibliográfico sobre as políticas públicas no setor de medicamentos brasileiro, o artigo examina as principais características das ações aplicadas na área, ressaltando seus resultados e deficiências, bem como as dificuldades encontradas para consolidar uma política de medicamentos no Brasil. O estudo realizado se fundamentou na análise de artigos por meio das bases de dados Scielo e Lilacs e de outras fontes. Desde a extinta Central de Medicamentos (CEME) até a aprovação da Política Nacional de Medicamentos (PNM), todas as ações e projetos foram voltados principalmente para a reorientação da Assistência Farmacêutica na atenção básica, garantindo, por conseguinte, o acesso e o uso racional dos medicamentos essenciais.

Through a bibliography review of public policies in Brazilian medicine sector, this paper examines the main characteristics of actions implemented in this area, lighting their results and deficiencies, as well as the difficulties to consolidate a policy for medicines in Brazil. The study is based on analysis of articles searched in the Scielo and Lilacs databases and other sources. Since the extinct Medicine Center to the approval of the National Medicine Policy, all the actions and programs aimed mainly at the reorientation of Pharmaceutical Assistance in primary health are, to guarantee access and rational use of essential medicines essential.

Metástasis de carcinoma de cérvix sobre cicatriz: dos casos clínicos / Incisional skin metastasis from a cervical carcinoma: report of two cases

La recidiva del cáncer de cérvix sobre la cicatriz quirúrgica abdominal tras cirugía es un hecho extremadamente raro. Actualmente, hay muy pocos casos publicados en la literatura médica. La supervivencia de estas mujeres es corta, pues el carcinoma de cérvix sobre cicatriz se considera como una recidiva de la enfermedad. El tratamiento en estos casos varía: cirugía, quimioterapia o radioterapia. A continuación se presentan 2 casos tratados quirúrgicamente y con tratamiento adyuvante. En la actualidad, ambas mujeres están vivas (AU)

Recurrence of cervical carcinoma in an abdominal surgical scar after radical surgery is extremely uncommon. Few reports have been published in the literature and survival in these patients is short; consequently this entity is considered to be a carcinoma recurrence. Treatment varies and may consist of surgery, chemotherapy or radiation. We present two cases treated with surgery and adjuvant therapy. Currently, both patients are still alive (AU)

Do intrauterine growth restriction and overweight at primary school age increase the risk of elevated body mass index in young adults?

Obesity is one of the rising public health problems characterized as a risk factor for many chronic diseases in adulthood. Early life events such as intrauterine growth restriction, as well as life style, are associated with an increased prevalence of this disease. The present study was performed to determine if intrauterine growth restriction interacts with overweight at primary school age to affect body mass index (BMI) in young adults. From June 1, 1978 to May 31, 1979, 6827 singleton liveborns from Ribeirão Preto, São Paulo State, Brazil, corresponding to 98 percent of all births at the 8 maternity hospitals, were examined and their mothers were interviewed. Samples from the initial cohort were examined again at primary school age (8 to 11 years of age) and at the time of military service (18 years of age). There were 519 male individuals with complete measurements taken in the three surveys. Intrauterine growth-restricted individuals had a BMI 0.68 kg/m² lower than that of individuals who were not restricted (95 percentCI = -1.34 to -0.03) and overweight at primary school age showed a positive and strong effect on BMI at 18 years of age (coefficient 5.03, 95 percentCI = 4.27 to 5.79). However, the increase in BMI was much higher - 6.90 kg/m² - when the conscript had been born with intrauterine growth restriction and presented overweight at primary school age (95 percentCI = 4.55 to 9.26). These findings indicate that the effect of intrauterine growth restrictionon BMI at 18 years of age is modified by later weight gain during school age.

Adaptador intercambiable para desfibrilación en pacientes pediátricos

En la actualidad, una de las principales causas de muerte a nivel mundial es el paro cardiaco, producido en muchas ocasiones debido a una fibrilación ventricular que requiere la aplicación de una descarga eléctrica a través del tórax del paciente. En términos generales, atendiendo a la edad, pueden identificarse dos tipos de pacientes: los pacientes adultos y los pacientes pediátricos, ambos susceptibles de aplicárseles desfibriladores externos. Entre las diferencias técnicas más importantes en ambos casos se encuentran los valores de la energía utilizada en el tratamiento y el área de los electrodos (paletas) con los que se aplica la descarga. En el presente trabajo se propone una solución para la detección de la presencia de un adaptador pediátrico y el cambio de las escalas de energía de desfibrilación para un desfibrilador-monitor diseñado por un grupo de trabajo multidisciplinario con la participación de los autores. Se presenta, además, unalgoritmo que facilita el diseño mecánico en 3D y su ulterior aplicación a la obtención de prototipos rápidos, como un medio de lograr una comprobación rápida y eficaz de los ajustes entre distintas piezas(AU)

Nowadays cardiac arrest constitutes one of the major death causes worldwide. Cardiac arrest is frequently produced by a ventricular fibrillation, which can be eliminated applying an electrical discharge to the thorax of the patient. Generally speaking, two patient types may be identified: adult and paediatric patients, both prone to develop ventricular fibrillation that can be eliminated with an external defibrillator. Among the main differences in both cases are the energy values of thedischarge and the area of the metallic electrode in contact with the skin. In this paper a new solution for detecting the presence of the paediatric adapter is presented that allows to limit the maximum selectable energy value, when used in conjunction with a biphasic defibrillator-monitordeveloped by a multidisciplinary work group with participation of the authors. An algorithm that eases the 3D mechanical design and its later application in rapad prototyping as a means to verify a fast and efficient coincidence of fittings among different pieces is presented(AU)

Un desfibrilador bifásico cubano portátil: características y resultados / A portable Cuban two-phase equipment: characteristics and results

En el trabajo se presentan las principales características de diseño del primer desfibrilador externo bifásico cubano, desarrollado por los autores. Se describen la arquitectura, los principales requisitos de seguridad y los resultados de los principalesensayos realizados durante la etapa de diseño. Finalmente se hace referencia al ensayo del desfibrilador en un modelo porcino y a los resultados obtenidos en la prueba de uso en humanos y a su subsiguiente aplicación, discutiéndose ambos ensayos. Se concluye que el equipo, que está dirigido al tratamientodel paro cardiaco por fibrilación ventricular y a la cardioversión sincronizada, puede ser aplicado con elevada seguridad tanto para el paciente como para el operador, logrando una eficacia semejante a la de equipos similares del mercado internacional(AU)

Dos grandes masas anexiales durante el embarazo: manejo en un caso concreto / Two large adnexal masses during pregnancy: management of a specific case

Se presenta el caso de una mujer de 33 años, con una gestación en el contexto de 2 grandes masas anexiales. Tras el estudio pertinente mediante ultrasonidos, marcadores tumorales y resonancia magnética se decide mantener una conducta expectante, con la que se obtuvo un buen resultado materno y fetal. Se resalta la importancia del manejo individualizado de las masas anexiales en el embarazo

We present the case of a 33-year-old woman who developed two large adnexal masses during pregnancy. Relevant tests including ultrasound, tumoral markers and magnetic resonance imaging were performed and an expectant approach was adopted. Maternal and fetal outcomes were favorable. The importance of individual management of adnexal masses in pregnancy is highlighted

Un desfibrilador bifásico cubano: características fundamentales

En el trabajo se presentan las principales características de diseño de un desfibrilador externo bifásico cubano, que se desarrolla por los autores. Se describen la arquitectura, los principales requisitos de seguridad y las pruebas realizadas al equipo. Finalmente se hace referencia al ensayo del prototipo de desfibrilador en un modelo porcino. Se presentan los resultados y se concluye que el equipo, que está dirigido al tratamiento del paro cardiaco por fibrilación ventricular, puede ser también aplicado con elevada seguridad a la cardioversión de pacientes con determinadas patologías(AU)

Expresión como proteínas de fusión de las subunidades PB1 y PB2 de la polimerasa del virus de la influenza / Expression how proteins of fusion of the subunits PB1 and PB2 of the influenza viral of polymerase

Los cADNs de los genes que codifican las proteínas PB1 y PB2 de la ARN polimerasa del virus de la influenza, se clonaron en fase en un sitio distal del ATG que codifica la proteína 10 del bacteriógafo T7, en el vector de expresión pAR3040, bajo el control de un promotor de la ARN polimerasa de T7. Los plásmidos recombinantes se introdujeron en la cepa bacteriana. E coli BL21 (DE3)plysS, que contiene en su genoma el gen de la ARN polimerasa del fago T7, bajo el control de un promotor (lac uv5) inducible por IPTG. La inducción de la ARN polimerasa del fago T7 en las células hospederas, resultó en la expresión de las proteínas PB1 y PB2 en forma de proteínas de fusión. Las proteínas expresadas se acumularon en grandes cantidades en el interior de las células bacterianas y fueron recuperadas de los lisados en forma de precipitados insolubles.

Determinantes psicológicos de los conflictos bélicos / Determinants of psychological warfare

El presente artículo constituye una serie de reflexiones sobre el uso de técnicas psicológicas con fines bélicos. La manipulación y el control del sistema de fuerzas que presionan a uno o más individuos se encuadra dentro de la metodología denominada de baja intensidad; y psicológicamente van dirigidas a disminuir la seguridad en sí misma, con el fin de instigar actos programados a priori y sin que se perciba tal control.

The following article constitutes a series of reflections about the use of psychological technics with bellicose finishes. Manipulation and control of the force system that pressure one or more individuals frame inside the methodology denominated of low intensity; and they are psychological direct to decrease the security in itself, with the finish of intricate program acts apriori without perceiving that control.

Inmunocomplejos circulantes en paciente de lepra multibacilar y su relación con los anticuerpos anti-M. leprae y las inmunoglobulinas mayores

Se realizó un estudio de la respuesta inmune humoral eb pacientes de lepra multibacilar, sus convivientes e individuos sanos sin contacto conecido con lepra. Los que dividieron en tres grupos: pacientes con menos de 2 años de tratamiento, pacientes que tenían más de 2 años de tratamiento y evolución satisfactoria y pacientes con más de 2 anõs de tratamiento que presentaban episodios de eritema nudosum leprosum. Se determinaran los niveles inmunocomplejos circulantes por el método de precipitación con polietilenglicol de 6000, los niveles de anticuerpos anti-M. leprae por técnica de ELISA utilizando el antígeno semisintético análogo del glicolípido fenótipo I del M. leprae y se cuantificaron las inmunoglobulinas IgA, IgG e IgM por inmunodifusión radial. En los pacientes con reacción tipo II, los valores de los inmunocomplejos y de las inmunoglobulinas IgG e IgA fueron más altos que en el resto de los grupos. La IgM y los anticuerpos anti-M. leprae disminuyeron con el tiempo de tratamiento, tendiendo ambos a una relación inversa con los inmunocoplejos.

Quantitation of chronic microwave radiation effects on muscle cell electrical excitable properties: a temperature dependence analysis of the H-H cable and membrane current parameters of irradiated cells

Frogs Rana pipiens maintained under constant laboratory environmental conditions were subjected daily to chronic microwave exposure with pulsed microwave (2.88 GHZ) at a power density of 10 mW/cm2, during 0.1 hour, for periods up to 100 days. The whole body Specific Absorption Rate (SAR) was of 1.5 mW/g per 1 mW/cm2. The passive and dynamic electrical parameters of sartorius muscle cells from control and irradiated frogs as a function of temperature in the range from 10 C to 30 C, have been analyzed. This temperature dependence analysis, presented in another work, was planned to be used in this paper for detecting those possible [quot ]masked[quot ] chronic microwave effects in complex membrane mechanisms highly temperature sensitive, and tightly related to the excitation and propagation of bioelectrical responses. The temperature dependence of the passive (Vr, Gm, Cm, and tau) and the active cell electrical parameters (theta, V*, Vs, VNa, Vn, V+, V-, kr, kNa, kK, tau Na, tau K, -gNa, gNa, gK, INa, and IK) was not altered by chronic microwave exposure. The striking observation reported in another work, about the presence of two groups of cell electrical parameters, characterized by their dependence with temperature, was reproduced on the irradiated muscle cells. Results have indicated that there was not muscle cell cumulative bioeffects resulting from microwave exposure to 10 mW/cm2, over a 0.1 hour period.

Temperature dependence on the passive and dynamic electrical parameters of muscle cells

Measurements of the temperature dependence in the range from 10 C to 30 C on the passive and dynamic electrical properties of single frog muscle cell following Arrhenius relation have been made. The propagated responses (V-t) and conduction velocity theta were analyzed following the H-H propagated cable equation. The ionic current-membrane potential relationship (I-t) was calculated from the phase-plane trajectory analysis (V-V) of the action potential curve (V-t). All the rate and time constants of the excitation and propagation processes kr, kNa, kK, tau Na, tau K, the negative conductance (-gNa) and the ionic conductances gNa, gK, influencing the evolution of the curves (V-t), (V-V) and (I-V) are correlated. The magnitudes of the resting (Vr) and action potential amplitude (Vs), the excitation potential (V*), the negative after potential (Vn), and the sodium equilibrium potential (VNa); the magnitudes of the maximum rate of rise and fall of the spike (V+) and (V-) and those corresponding to the inward INa and outward IK ionic currents, were analyzed. Two general classes of findings were obtained. One group of action potential parameters theta, V+, V-, Vn, kr, kNa, kK, tau Na, tau K, -gNa, gNa, gK, INa and IK is strongly temperature dependent with Q 10 S approximately 2 and energy of activation E approximately 10 kcal/mole. The other group of parameters, Gm (passive conductance), Cm (capacitance), tau, Vr, V*, Vs, and VNa are slightly temperature dependent, with Q10’s lower than 1.4. This study contributes deeply to the analysis of temperature effects on the electrical cell responses to adequate stimuli. This temperature dependence analysis was designed to detect possible [quot ]masked[quot ] actions of microwave radiation on cell membrane functions.

Temperature dependence on the passive and dynamic electrical parameters of muscle cells.

Measurements of the temperature dependence in the range from 10 C to 30 C on the passive and dynamic electrical properties of single frog muscle cell following Arrhenius relation have been made. The propagated responses (V-t) and conduction velocity theta were analyzed following the H-H propagated cable equation. The ionic current-membrane potential relationship (I-t) was calculated from the phase-plane trajectory analysis (V-V) of the action potential curve (V-t). All the rate and time constants of the excitation and propagation processes kr, kNa, kK, tau Na, tau K, the negative conductance (-gNa) and the ionic conductances gNa, gK, influencing the evolution of the curves (V-t), (V-V) and (I-V) are correlated. The magnitudes of the resting (Vr) and action potential amplitude (Vs), the excitation potential (V*), the negative after potential (Vn), and the sodium equilibrium potential (VNa); the magnitudes of the maximum rate of rise and fall of the spike (V+) and (V-) and those corresponding to the inward INa and outward IK ionic currents, were analyzed. Two general classes of findings were obtained. One group of action potential parameters theta, V+, V-, Vn, kr, kNa, kK, tau Na, tau K, -gNa, gNa, gK, INa and IK is strongly temperature dependent with Q 10 S approximately 2 and energy of activation E approximately 10 kcal/mole. The other group of parameters, Gm (passive conductance), Cm (capacitance), tau, Vr, V*, Vs, and VNa are slightly temperature dependent, with Q10s lower than 1.4. This study contributes deeply to the analysis of temperature effects on the electrical cell responses to adequate stimuli. This temperature dependence analysis was designed to detect possible [quot ]masked[quot ] actions of microwave radiation on cell membrane functions.

Quantitation of chronic microwave radiation effects on muscle cell electrical excitable properties: a temperature dependence analysis of the H-H cable and membrane current parameters of irradiated cells.

Frogs Rana pipiens maintained under constant laboratory environmental conditions were subjected daily to chronic microwave exposure with pulsed microwave (2.88 GHZ) at a power density of 10 mW/cm2, during 0.1 hour, for periods up to 100 days. The whole body Specific Absorption Rate (SAR) was of 1.5 mW/g per 1 mW/cm2. The passive and dynamic electrical parameters of sartorius muscle cells from control and irradiated frogs as a function of temperature in the range from 10 C to 30 C, have been analyzed. This temperature dependence analysis, presented in another work, was planned to be used in this paper for detecting those possible [quot ]masked[quot ] chronic microwave effects in complex membrane mechanisms highly temperature sensitive, and tightly related to the excitation and propagation of bioelectrical responses. The temperature dependence of the passive (Vr, Gm, Cm, and tau) and the active cell electrical parameters (theta, V*, Vs, VNa, Vn, V+, V-, kr, kNa, kK, tau Na, tau K, -gNa, gNa, gK, INa, and IK) was not altered by chronic microwave exposure. The striking observation reported in another work, about the presence of two groups of cell electrical parameters, characterized by their dependence with temperature, was reproduced on the irradiated muscle cells. Results have indicated that there was not muscle cell cumulative bioeffects resulting from microwave exposure to 10 mW/cm2, over a 0.1 hour period.

Digitalizer system and memory for electric transients

It was designed a fast solid state electronic waveform recording system (Digitalizer), which can record, store and display action potentials or any type of event, either single pulse or repetitive, as a function of time. Above all, its capacity to record fast transients and to give the output in analog and digital form, makes this electronic device more convenient that conventional recorders or single trace oscilloscope systems.