Utilidad de la midodrina para controlar el síncope vasovagal: ¿la recomienda la evidencia? / Usefulness of Midodrine for the Control of Recurrent Vasovagal Syncope: Does the Evidence Recommend it? / Utilidade da midodrina no controle da síncope vasovagal: as evidencias a recomendam?

Introducción:El síncope vasovagal es la principal causa de pérdida transitoria de la conciencia, y es un motivo de consulta cada vez más frecuente en pediatría y medicina del adulto. La midodrina es un agonista de los recepto-res alfa, de acción periférica, empleada principalmente en el manejo de la hipotensión ortostática; sin embargo, también se ha evaluado en el síncope vasovagal, con resultados prometedores.Objetivo:Analizar la evidencia más reciente sobre la utilidad de la midodrina para el control y la prevención del síncope vasovagal.Materiales y métodos: Se realizó una búsqueda bibliográfica utilizando términos de búsqueda como Vasovagal Syncope y Midodrine, así como sinónimos, que se combinaron con operadores booleanos, en cinco bases de datos, hasta octubre del 2022. Se incluyeron estudios originales, revisiones sistemáticas y metanálisis, publicados tanto en inglés como en español.Resultados:Ensayos controlados aleatorizados y revisiones sistemáticas y metanálisis difieren ligeramente entre resultados, pero estos demuestran un efecto global protector. La evidencia más reciente y completa indica que utilizar este agente reduce significativamente la positividad al realizar la prueba de la mesa inclinada y que previene la aparición de episodios sincopales.Conclusiones:Aunque la evidencia actual sobre la eficacia de la midodrina respecto a la prevención y control del síncope vasovagal es limitada, se observa un efecto protector significativo, porque disminuye el riesgo de sufrir un episodio sincopal, aproximadamente hasta en un 50 %.Palabras clave: midodrina; síncope vasovagal; síncope; adrenérgicos; medicina basada en la evidencia

Introduction: Vasovagal syncope is the main cause of transient loss of consciousness, being an in-creasingly frequent reason for consultation in pediatrics and adult medicine. Midodrine, a periphe-rally acting alpha-receptor agonist, is mainly used in the management of orthostatic hypotension. However, it has also been evaluated in vasovagal syncope, with promising results. Objective: To analyze the most recent evidence on the usefulness of midodrine for the control and prevention of vasovagal syncope. Materials and Methods: A literature search was performed using search terms such as "Vasovagal Syncope" and "Midodrine," as well as synonyms, which were combined with Boolean operators, in 5 databases until October 2022. Original studies, systematic reviews and meta-analyses, published in both English and Spanish, were included. Results: Randomized controlled trials and systematic reviews and meta-analyses differ slightly between results, but these demonstrate an overall protective effect. The most recent and complete evidence shows that using this agent significantly reduces the probability of positivity when performing the tilt table test and prevents the occurrence of syncopal episodes. Conclusions: Although current evidence on the efficacy of midodrine with respect to the prevention and control of vasovagal syncope is limited, a significant protective effect is observed, reducing the risk of suffering syncopal episode by approximately up to 50%

Introdução: a síncope vasovagal é a principal causa de perda transitória de consciência e é um motivo cada vez mais comum de consulta em pediatria e medicina de adultos. A midodrina é um agonista do receptor alfa de ação periférica usado principalmente no tratamento da hipotensão ortostática; no entanto, ela também foi avaliada na síncope vasovagal, com resultados promissores. Objetivo: Revisar as evidências mais recentes sobre a utilidade da midodrina para o controle e a pre-venção da síncope vasovagal. Materiais e métodos: Foi realizada uma pesquisa na literatura usando termos de pesquisa como Va-sovagal, Syncope e Medodrine, bem como sinônimos, que foram combinados com operadores boo-leanos, em cinco bancos de dados, até outubro de 2022. Foram incluídos estudos originais, revisões sistemáticas e metanálises, publicados em inglês e espanhol. Resultados: Os ensaios clínicos randomizados, as revisões sistemáticas e as metanálises diferem ligei-ramente entre os resultados, mas demonstram um efeito protetor geral. As evidências mais recentes e abrangentes indicam que o uso desse agente reduz significativamente a positividade no teste de inclinação da mesa e evita a ocorrência de episódios de síncope. Conclusões: Embora as evidências atuais sobre a eficácia da midodrina em relação à prevenção e ao controle da síncope vasovagal sejam limitadas, observa-se um efeito protetor significativo, pois ela diminui o risco de sofrer um episódio sincopal em aproximadamente 50%

Efectos clinicos e histopatologicos agudos y subagudos del veneno de Tityus breweri en miocardio de hamsters / Clinical and histopathological effects of acute and subagude of the poison of Tityus breweri in hamsters myocardia

Resumen Los escorpiones del género Tityus presentan la mayor distribución mundial, de mayor importancia clínica, epidemiológica y más peligrosa del continente americano. Las toxinas de su veneno producen perturbación severa de los procesos de excitación y conducción del impulso nervioso. Desde el punto de vista histopatológicos se han observado cambios estructurales en diferentes tejidos de ratones, con el veneno de varias especies de Tityus venezolanos. Objetivo: Describir los efectos clínicos e histopatológicos agudos y subagudos del veneno de escorpión (Buthidae: T. breweri) en el miocardio de hámster. Método: Estudio experimental, exploratoria, descriptivo, analítica y correlacional. Se utilizaron hámsteres de ambos sexos del genero Cricetus y se obtuvo el veneno de 26 escorpiones T. breweri, se escogieron 6 hámster al azar, inyectándoles vía intraperitonial (VIP) veneno de Tityus breweri, 3 sacrificados a los 30 minutos y los otros 3 a los 60 minutos, 3 inyectados con agua destilada constituyeron el grupo control. Resultados: La mayoría de los animales expuestos presentaron manifestaciones de tipo colinérgicas y adrenérgicas. Las alteraciones histopatológicas agudas observadas fueron edema interfascicular y congestión vascular, infiltrado linfohistiocítico perivascular. Al transcurrir 12, 24, 48 y 72 horas de exposición del veneno, no se evidenciaron cambios histopatológicos, lo que hace presumir que se activaron los procesos de reparación de los tejidos dañados. Conclusión: el veneno de T. breweri produjo alteración histológicas agudas y subagudas en el tejido miocárdico en los hámsteres sin evidencia de alteración en el grupo control.

Abstract Scorpions of the genus Tityus present the largest distribution of the world, of greater clinical, epidemiological and more dangerous importance of the American continent. The toxins from its venom produce severe disturbance of the excitation and conduction processes of the nerve impulse. From the histopathological point of view structural changes have been observed in different tissues of mice, with the venom of several species of Venezuelan Tityus. Objective: To describe the acute and subacute clinical and histopathological effects of scorpion venom (Buthidae: T. breweri) on the hamster myocardium. Method: Experimental, exploratory, descriptive, analytical and correlational study. Hersters of both sexes of the genus Cricetus were obtained and venom of 26 T. breweri scorpions were obtained, 6 random hamsters were chosen, injecting intravenously (VIP) venom of Tityus breweri, 3 sacrificed at 30 minutes and the other 3 a The 60 minutes, 3 injected with distilled water constituted the control group. Results: Most of the exposed animals presented cholinergic and adrenergic type manifestations. The acute histopathological alterations observed were interfascicular edema and vascular congestion, perivascular lymphohistiocytic infiltrate. At the end of 12, 24, 48 and 72 hours of exposure of the venom, no histopathological changes were evidenced, which suggests that the repair processes of the damaged tissues were activated. Conclusion: T. breweri venom caused acute and subacute histological alterations in myocardial tissue in hamsters with no evidence of alteration in the control group.

Influencia adrenérgica y colinérgica sobre la producción de especies reactivas de oxígeno en neutrófilos humanos* / Adrenergic and cholinergic influence on the production of reactive oxygen species in human neutrophils*

RESUMEN Objetivos. Determinar y comparar el efecto de fármacos agonistas adrenérgicos y colinérgicos sobre la producción de especies reactivas de oxígeno (ROS) en neutrófilos de individuos sanos. Materiales y métodos. Se tomaron muestras de sangre total de cinco participantes para purificar los neutrófilos mediante el método de gelatina. Se midió la producción de ROS por quimioluminiscencia (QLM) usando un contador de centelleo y forbol-12-miristato-13-acetato (PMA) como estímulo. También se realizaron pruebas sin PMA para medir la producción espontánea. Posteriormente, con el mismo método se midió la formación de ROS en presencia de nicotina (agonista colinérgico), salbutamol y clonidina (agonistas adrenérgicos), cada uno en concentraciones de 10-2 M, 10-3 M, 10-4 M y 10-5 M. Se calculó el área integrada bajo las curvas de QLM y se halló el porcentaje de inhibición o de estimulación según sea el caso. Se comparó el efecto provocado por las drogas con sus controles correspondientes y se realizó el análisis estadístico. Resultados. Se obtuvo una disminución de la producción de ROS como efecto de las sustancias estudiadas con una diferencia significativa entre los controles y el efecto producido a 10-2 M, 10-3 M y 10-4 M. Este efecto aumentó de intensidad conforme la concentración de las drogas se incrementó. Los mayores porcentajes de inhibición se mostraron a 10-2 M y 10-3 M. Salbutamol presentó los máximos valores con todas las concentraciones con diferencia significativa entre su inhibición y la generada por las demás drogas. Conclusiones. Los estímulos adrenérgico y colinérgico tienen un efecto inhibitorio de la producción de ROS en neutrófilos de individuos sanos.

ABSTRACT Objectives. To determine and compare the effect of adrenergic and cholinergic agonist drugs on the production of reactive oxygen species (ROS) in neutrophils of healthy individuals. Materials and Methods. Whole blood samples were taken from five participants to purify neutrophils using the gelatin method. The production of chemiluminescent (QLM) ROS was measured using a scintillation counter and phorbol-12-myristat-13-acetate (PMA) as a stimulus. Non-PLA tests were also conducted to measure spontaneous production. Subsequently, with the same method, ROS formation was measured in the presence of nicotine (cholinergic agonist), salbutamol, and clonidine (adrenergic agonists), each in concentrations of 10-2 M, 10-3 M, 10-4 M, and 10-5 M. The area integrated under the QLM curves was calculated and the percentage of inhibition or stimulation was found as the case may be. The effect of the drugs was compared with their corresponding controls and statistical analysis was carried out. Results. A decrease in the production of ROS was obtained as an effect of the substances studied with a significant difference between the controls and the effect produced at 10-2 M, 10-3 M, and 10-4 M . This effect increased in intensity as drug concentration increased. The highest percentages of inhibition were shown at 10-2 M and 10-3 M. Salbutamol presented the maximum values with all the concentrations with a significant difference between its inhibition and that generated by the other drugs. Conclusions. Adrenergic and cholinergic stimuli have an inhibitory effect on the production of ROS in neutrophils of healthy individuals.

Neonatal Maternal Deprivation Followed by Adult Stress Enhances Adrenergic Signaling to Advance Visceral Hypersensitivity / 神经科学通报·英文版

The pathophysiology of visceral pain in patients with irritable bowel syndrome remains largely unknown. Our previous study showed that neonatal maternal deprivation (NMD) does not induce visceral hypersensitivity at the age of 6 weeks in rats. The aim of this study was to determine whether NMD followed by adult stress at the age of 6 weeks induces visceral pain in rats and to investigate the roles of adrenergic signaling in visceral pain. Here we showed that NMD rats exhibited visceral hypersensitivity 6 h and 24 h after the termination of adult multiple stressors (AMSs). The plasma level of norepinephrine was significantly increased in NMD rats after AMSs. Whole-cell patch-clamp recording showed that the excitability of dorsal root ganglion (DRG) neurons from NMD rats with AMSs was remarkably increased. The expression of β adrenergic receptors at the protein and mRNA levels was markedly higher in NMD rats with AMSs than in rats with NMD alone. Inhibition of β adrenergic receptors with propranolol or butoxamine enhanced the colorectal distention threshold and application of butoxamine also reversed the enhanced hypersensitivity of DRG neurons. Overall, our data demonstrate that AMS induces visceral hypersensitivity in NMD rats, in part due to enhanced NE-β adrenergic signaling in DRGs.

Mecanismo de Frank Starling: una visión aplicada en la erección del pene / Frank-Starling Mechanism: A Vision Applied To Penile Erection

El mecanismo de Frank-Starling es un concepto básico de la fisiología cardíaca y su aprendizaje. Constituye la base fundamental para el entendimiento del funcionamiento del corazón y patologías prevalentes y con alta morbimortalidad como lo es la insuficiencia cardíaca. Por lo cual, su relación con un proceso más interactivo como la erección del pene, podría asegurar un aprendizaje perdurable y práctico. La relación se fundamentó en el reemplazo del eje X de la curva por precarga en el caso del corazón y estimulación en el caso del pene, para así lograr una relación incluso con la disfunción eréctil, que sería el equivalente a la insuficiencia cardíaca. De esa manera, se encontró que a mayor estimulación hay mayor erección y a mayor precarga hay mayor eyección ventricular, teniendo ambas curvas una meseta. Asímismo, farmacológicamente, se encontró relación con el uso de estimulación ß-adrenérgica y de inhibidores selectivos de la fosfodiesterasa tipo 5 como el sildenafil, los cuales desplazan la curva hacia arriba y a la izquierda.

The Frank-Starling mechanism is a basic concept of cardiac physiology and the fundamental basis for understanding the cardiac performance and prevalent disorders at risk of high morbidity and mortality, such as heart failure. Therefore, its relation with an interactive process like penile erection may enable deeper insight into cardiac physiology. The X-axis of Frank-Starling's curve was changed from ventricular end-diastolic volume to stimulation, to achieve a relation that includes erectile dysfunction, which is the equivalent of heart failure. A direct relationship was found between stimulation and erection, as well as end-diastolic volume and ventricular ejection with a plateau in both curves. Likewise, pharmacologically, a relation was identified with the use of ß-adrenergic and selective inhibitor of phosphodiesterase (PDE) type 5 like sildenafil, which shift leftward and upward the Frank-Starling curve

Electroacupuncture Alleviates Motor Symptoms and Up-Regulates Vesicular Glutamatergic Transporter 1 Expression in the Subthalamic Nucleus in a Unilateral 6-Hydroxydopamine-Lesioned Hemi-Parkinsonian Rat Model / 神经科学通报·英文版

Previous studies have shown that electroacupuncture (EA) promotes recovery of motor function in Parkinson's disease (PD). However the mechanisms are not completely understood. Clinically, the subthalamic nucleus (STN) is a critical target for deep brain stimulation treatment of PD, and vesicular glutamate transporter 1 (VGluT1) plays an important role in the modulation of glutamate in the STN derived from the cortex. In this study, a 6-hydroxydopamine (6-OHDA)-lesioned rat model of PD was treated with 100 Hz EA for 4 weeks. Immunohistochemical analysis of tyrosine hydroxylase (TH) showed that EA treatment had no effect on TH expression in the ipsilateral striatum or substantia nigra pars compacta, though it alleviated several of the parkinsonian motor symptoms. Compared with the hemi-parkinsonian rats without EA treatment, the 100 Hz EA treatment significantly decreased apomorphine-induced rotation and increased the latency in the Rotarod test. Notably, the EA treatment reversed the 6-OHDA-induced down-regulation of VGluT1 in the STN. The results demonstrated that EA alleviated motor symptoms and up-regulated VGluT1 in the ipsilateral STN of hemi-parkinsonian rats, suggesting that up-regulation of VGluT1 in the STN may be related to the effects of EA on parkinsonian motor symptoms via restoration of function in the cortico-STN pathway.

Correlation of Beta-2 Adrenergic Receptor Expression inTumor-Free Surgical Margin and at the Invasive Front ofOral Squamous Cell Carcinoma

Background. The beta-2 adrenergic receptor is expressed by neoplastic cells and is correlated with a wide spectrum of tumor cell mechanisms including proliferation, apoptosis, angiogenesis, migration, and metastasis. Objectives. The present study aimed to analyze the expression of the beta-2 adrenergic receptor (ß2-AR) in tumor-free surgical margins of oral squamous cell carcinomas (OSCC) and at the invasive front. Sixty-two patients diagnosed with OSCC, confirmed by biopsy, were selected for the study. The clinicopathological data and clinical follow-up were obtained from medical records and their association with ß2-AR expression was verified by the chi-square test or Fischer's exact test. To verify the correlation of ß2-AR expression in tumor-free surgical margins and at the invasive front of OSCCs, Pearson's correlation coefficient test was applied. Results. The expression of ß2-AR presented a statistically significant correlation between the tumor-free surgical margins and the invasive front of OSCC (r = 0.383; p = 0.002). The immunohistochemical distribution of ß2-AR at the invasive front of OSCC was also statistically significant associated with alcohol (p = 0.038), simultaneous alcohol and tobacco consumption (p = 0.010), and T stage (p = 0.014). Conclusions. The correlation of ß2-AR expression in OSCC and tumor-free surgical margins suggests a role of this receptor in tumor progression and its expression in normal oral epithelium seems to be constitutive

Leaf extract from Clusia nemorosa induces an antinociceptive effect in mice via a mechanism that is adrenergic systems dependent / 中国天然药物

Previous studies on the genus Clusia have shown anti-inflammatory and antiproliferative effects of the leaf extracts, but its antinociceptive activity has never been characterized. In the present study, the antinociceptive activity of the hexane extract of the leaves of Clusia nemorosa G. Mey, called HECn, was examined. Antinociceptive activity was evaluated using acetic acid-induced writhing, formalin, and hot-plate tests. All experiments were carried out on male Swiss mice. The extract (1-400 mg·kg(-1)), given by intraperitoneal route (i.p.) 1 h prior to testing, produced a dose-dependent inhibition on the number of abdominal writhings, with an ID50 of 62 mg·kg(-1). In addition, HECn was able to prevent the visceral pain induced by acetic acid in mice for at least 2 h. In the formalin test, HECn had no effect in the first phase, but produced an analgesic effect on the second phase with the inhibition of licking time. The HECn did not show a significant analgesic effect in the hot plate test. Pretreatment with yohimbine attenuated the antinociceptive effect induced by HECn in the writhing test. However, naloxone, atropine, or haloperidol did not affect antinociception induced by HECn in the writhing test. Together, these results indicate that the extract from the leaves of Clusia nemorosa produces antinociception in models of chemical pain through mechanisms that suggest participation of the adrenergic systems pathway.

Update on congenital glaucoma.

Congenital glaucoma is a global problem and poses a diagnostic and therapeutic challenge to the ophthalmologist. A detailed evaluation under general anesthesia is advisable to establish the diagnosis and plan for management. Medical therapy has a limited role and surgery remains the primary therapeutic modality. While goniotomy or trabeculotomy ab externo is valuable in the management of congenital glaucoma, primary combined trabeculotomy–trabeculectomy offers the best hope of success in advanced cases. Trabeculectomy with antifibrotic agent and glaucoma drainage devices has a role in the management of refractory cases, and cyclodestructive procedures should be reserved for patients where these procedures have failed. Early diagnosis, prompt therapeutic intervention and proper refractive correction are keys to success. Management of residual vision and visual rehabilitation should be an integral part of the management of children with low vision and lifelong follow-up is a must.

Effects of low level of lead exposure on blood pressure and responsiveness of the rat isolated heart to adrenergics

Exposure to low levels of lead increases blood pressure in humans and animals. Although there are controversial reports about the exact mechanisms of lead-induced hypertension, many factors such as alteration in the cardiovascular responsiveness to endogenous substances including catecholamines could be one of the mechanisms involved. In the present study, the effect of lead acetate on the systolic blood pressure and responsiveness to beta-adrenergics was investigated in rats. Through their drinking water, three groups of rats were exposed to 100 ppm lead acetate for periods of 4, 8 or 12 weeks. The blood pressures of the rats were monitored throughout the study. The rat hearts were isolated and perfused with Krebs-Henseleit solution [pH = 7.4] at 37°C and gassed with 95% O2 + 5% CO[2]. The heart rate [chronotropic] and contractile [inotropic] responses were recorded before and after adding isoproterenol at multiple concentrations to the perfusion solution. The mean blood pressures in the 8 and 12-week lead-treated groups were significantly higher than that of the control group [P < 0.01]. The chronotropic response to many doses of isoproterenol was significantly increased in the 12-week lead-treated group compared to that of the control group [P < 0.05]. The inotropic response to this drug was significantly increased in both the 8- and 12-week lead-treated rats [P < 0.05 and P < 0.01, respectively]. Our results indicate that low-levels of lead increase systolic blood pressure as well as both chronotropic and inotropic effects of beta-adrenergics, which could imply an important role in the pathogenesis of lead-induced hypertension

The a2CDel322-325 Adrenergic Receptor Polymorphism is not Associated with Heart Failure due to Idiopathic Dilated Cardiomyopathy in Black Africans : Cardiovascular Topics

Background : A four-amino acid deletion was identified within the a2C-adrenergic receptor (a2CDel322-325) that; when homozygous; increases the risk of heart failure in African-Americans nearly six-fold. We hypothesised that homozygosity for the a2CDel322-325 polymorphism may be a risk factor for heart failure due to idiopathic dilated cardiomyopathy (DCM) in black South Africans. Methods: The a2CDel322-325 polymorphism was genotyped in 37 patients with heart failure and 34 controls; all of black African ancestry. Genotyping was performed by a size-fractionation assay. Results: The patients studied ranged in age from 21 to 79 years with a mean age of 50 years; and 62were male. No significant difference was observed in homozygosity for the a2CDel322-325 polymorphism or in allele and genotype frequencies between patients and controls. The frequency of the allele containing the deletion was 0.54 in cases and 0.53 in controls. The genotype frequencies in the patients were consistent with those of the controls (p = 0.56). Conclusions: Homozygosity for the a2CDel322-325 polymorphism is not associated with an increased risk for heart failure due to idiopathic DCM in black South Africans

Effects of experimental amitraz intoxication in cats

This work studied the effects of experimental amitraz intoxication in cats. Sixteen cats were randomly divided equally into two groups: amitraz group - animals received 1.5 percent amitraz at 1mg/kg IV; and the control group - animals without amitraz. Physiological parameters from blood, cardiorespiratory system, and sedation indicators were quantified over time up to 360 minutes. Blood profile, urea, creatinine, alananine aminotransferase and aspartate aminotransferase were not affected by amitraz. Sedation, loss of reflexes, hypothermia, bradycardia, bradyarrhythmia, hypotension, bradypnea, mydriasis, besides transitory hyperglycemia, hypoinsulinemia and decrease of cortisol levels were observed in cats experimentally exposed to amitraz. The alpha2-adrenergic effects induced by amitraz intoxication in cats are very similar to the same effects reported in others species, contributing with more information about this type of intoxication to veterinary toxicology

Este trabalho estudou os efeitos da intoxicação experimental por amitraz em 16 gatos, distribuídos, aleatoriamente, em dois grupos: grupo amitraz - animais receberam amitraz a 1,5 por cento na dose de 1,0 mg/kg IV; e grupo controle - animais sem amitraz. Parâmetros fisiológicos sangüíneos, do sistema cardiorespiratório e de sedação foram aferidos até 360min. Perfil sangüíneo, uréia, creatinina, alanina aminotransferase e aspartato aminotransferase não foram afetados pelo amitraz. Sedação, perda de reflexos, hipotermia, bradicardia, bradiarritmias, hipotensão, bradipnéia, midríase, além de transitória hiperglicemia, hipoinsulinemia e diminuição dos níveis de cortisol, foram observados nos gatos experimentalmente expostos ao amitraz. Os efeitos alfa 2-adrenérgicos induzidos pela intoxicação por amitraz em gatos são muito similares aos mesmos efeitos relatados em outras espécies, contribuindo com mais informações dessa intoxicação para a toxicologia veterinária

Efeito do propofol associado à efedrina no tempo de latência do cisatracúrio / Effect of propofol in combination with ephedrine upon the onset time of cisatracurium

OBJETIVOS: Este estudo teve por objetivo avaliar a eficácia da efedrina na prevenção dos efeitos hemodinâmicos induzidos pela associação do propofol e do remifentanil, assim como os efeitos sobre o tempo de latência do cisatracúrio. MÉTODOS: Sessenta pacientes com idade entre 18 e 52 anos, estado físico ASA I ou II, foram divididos em três grupos, aleatoriamente: G I - propofol 1 por cento; G II - propofol 1 por cento + efedrina 0,5 mg.ml-1 e G III - propofol 1 por cento + efedrina 1,0 mg.ml-1 (velocidade de infusão igual a 180 ml.h-1), até a perda da consciência. Administrou-se remifentanil (0,5 mg.kg-1.min-1) e cisatracúrio na dose de 0,15 mg.kg-1. Foram registrados os dados demográficos, os sinais vitais (PAS, PAM, PAD, FC e SpO2) e o tempo de latência do cisatracúrio. RESULTADOS: Os grupos foram homogêneos com relação aos dados demográficos. Houve diminuição estatisticamente significativa dos valores de PAS, PAM, PAD e FC, um e três minutos após a administração do propofol, porém sem significado clínico importante e sem diferença entre os grupos. As medianas para os tempos de latência do cisatracúrio foram: 178 s (G2 e G3) e 183 s (G1), mas sem diferença significante entre os grupos. CONCLUSÃO: Não houve diminuição clinicamente importante dos parâmetros hemodinâmicos avaliados nos grupos que receberam ou não a efedrina e o tempo de latência do cisatracúrio foi o mesmo para os diferentes grupos.

OBJECTIVE: The onset time of neuromuscular blocking drugs is partially determined by circulatory factors, including muscle blood flow and cardiac output. The aim of the present paper was to: 1) compare the haemodynamic effects of adding different doses of ephedrine to an induction dose of propofol and remifentanil. 2) onset time of cisatracurium. METHODS: Sixty patients were randomly allocated into three groups: G1 - 1 percent propofol; G2 - 1 percent propofol + 0.5 mg.ml-1 ephedrine and G3 - 1 percent propofol + 1.0 mg.ml-1 ephedrine. All patients received continuous infusion of remifentanil (0.5 mg.kg-1.min-1). The rate of propofol infusion was 180 ml.h-1 until loss of consciousness and a loading dose of cisatracurium (0.15 mg.kg-1) was then given. After induction of anesthesia, the ulnar nerve was stimulated supramaximally every 10s, and the evoked twitch response of the adductor pollicis was recorded by accelerometry. RESULTS: There was no statistical difference between groups with respect to age, weight, dose of propofol administered and onset time of cisatracurium (tables 1, 2). Heart rate, SpO2, systolic, diastolic and mean blood pressures were compared at 1 and 3 min post-induction. There were statistical differences in HR, SAP, DAP and MAP, without significant adverse clinical effects. CONCLUSIONS: There were no clinically important decreases in the hemodynamic parameters evaluated in the groups receiving ephedrine or not, and the onset time of cisatracurium was the same for all groups.

Therapeutic effect of microencapsulated porcine retinal pigmented epithelial cells transplantation on rat model of Parkinson's disease / 神经科学通报·英文版

<p><b>OBJECT</b>To investigate the therapeutic effect of microencapsulated porcine retinal pigmented epithelial cells (RPE-M) transplantation on rat model of Parkinson's disease (PD).</p><p><b>METHODS</b>Primary porcine RPE cells were harvested by enzyme digestion and expanded in culture medium. Determine the levels of dopamine (DA) and homovanillic acid (HVA) by high performance liquid chromatography electrochemical (HPLC) assay, and the levels of brain-derived neurotrophic factor (BDNF) and glial-derived neurotrophic factor (GDNF) were detected by ELISA. Alginate-polylysine-alginate (APA) microencapsulated cells were produced by using a high voltage electrostatic system. PD rat model was established by unilateral injection of 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle (MFB). After that, the RPE-M was transplanted into the corpus striatum of PD rat, and then the rotation test scores were recorded and biochemical changes of the corpus striatum were tested.</p><p><b>RESULTS</b>The levels of DA, HVA, BDNF and GDNF secreted by RPE were stable in the RPE culture supernatant and were not changed by the microencapsulation. Eighty-three percent rats developed PD by unilateral lesion of 6-OHDA in the MFB. The RPE-M transplantation had therapeutic effect on 33% PD rats.</p><p><b>CONCLUSION</b>Porcine RPE cells grow actively in vitro and could secrete DA, HVA, BDNF, and GDNF constantly, which does not be affected by the passage culture and the APA miroencapsulation. RPE-M transplantation of may be a curative therapy for PD.</p>

Sistemas de liberacion controlada de mucoadhesivos utilizando carrageenan y RLPO eudragit / Mucoadhesive delivery systems using carrageenan and eudragit RLPO

El objetivo de esta investigación es desarrollar una tableta de dos capas de liberación controlada. Fueron comparados el comportamiento de la liberación de la droga y las propiedades físicas de las formulaciones de las tabletas usando dos polímeros (Carrageenan 934 y Eudragit RLPO) a tres niveles y a diferentes razones, a un nivel total de polímero de 40 (por ciento) p/p. Las formulaciones con dos polímeros a un nivel de 40 (por ciento) controlaron la liberación de la droga mejor que las que contenían un polímero. Las tabletas a razón (1:1) liberaron 46.4 (por ciento) mientras que las formulaciones a razones 3:1 y 1:3 liberaron 58.9 (por ciento) y 72.9 (por ciento). La formulación con razón (1:1) fue seleccionada la mejor y probada para la disolución en HCl 0.1N y una solución amortiguadora de fosfato a pH 7.4 en adición a agua destilada. La liberación de la droga en la solución amortiguadora fue 96.3 (por ciento) , en HCl y agua destilada fue 59.1 (por ciento) y 46.4 8por ciento). Este estudio demuestra la importancia del uso de la combinación de polímeros para obtener una matriz bioadhesiva de liberación controlada y realzar las características de cada polímero

Comparison of the effect of sympathetic agonist and antagonist on rabbits perfused heart: a study on simple and succussed dilutions

The pharmacological effect of Adrenaline and Atenolol dilutions / succussion is still unexplainable for their reverse effect on tissues. This effect of potentization is observed in the recent study with differences in the effect of simple and succussed dilutions on heart rate. For this purpose, both simple and succussed dilutions of Adrenaline and Atenolol were prepared serially, ranging from 10 [-3] to 10 [-36] for testing on the isolated perfused Rabbit's heart. Langendorff heart assembly was used to perfuse the heart and its activity was recorded on Oscillograph through isotonic transducer. The significant difference between the effects of simple and succussed dilutions of Adrenaline at 10 [-3] and 10 [-4] and for Atenolol 10 [-5], 10 [-11], 10 [-27], 10 [-30], 10 [-33] and 10 [-36] was observed on heart rate respectively. This study confirms that there are differences in the effects of simple and succussed dilutions. While potentization or reverse effect observed than normal has been found in-consistently throughout the range of dilutions used. Thus in-consistency expresses the instability of change in parent drug molecule on succussion

Variabilidade da frequência cardíaca em um teste de exercício verdadeiramente máximo / heart rate variability in a truly maximum exercise testing

fundamentos: O pico do exercício se caracteriza por uma grande redução da participação vagal e um concomitante aumento da atividade adrenérgica. Hipotetiza-se não haver variabilidade importante da frequencia cardíaca (VFC) no domínio do tempo no pico do esforço.Objetivo: Comparar a VFC no domínio do tempo em diferentes fases do teste de exercício máximo: repouso, limiar anaeróbico, pico do esforço e ao final do primeiro minuto da recuperação, identificando possíveis variações em função do gênero, condição aeróbica, condição clínica e da magnitude do indice vagal cardíaco nessas respostas da VFC.Métodos: foram revisados retrospectivamente 100 exames de indivíduos que atenderam aos seguintes critérios: a)indivíduos não-atletas com idade mínima de 18 anos; b)realização de teste cardiopulmonar de exercício máximo (TCPE), em cicloergômetro de membros inferiores; c)ausência de doença arterial coronariana conhecida ou de síndrome metabólica; d) não uso de medicação de ação cronotrópica negativa; e)duração do teste entre 8 e 12 minutos...

Increased subthalamic neuronal activity after dorsal raphe nucleus lesion by 5,7-dihydroxytryptamine in the rat / 生理学报

In vivo extracellular recordings were made in the subthalamic nucleus (STN) of intact control rats and rats with 5,7-dihydroxytryptamine (5,7-DHT) -produced lesion of dorsal raphe nucleus (DRN). The results showed that the firing rate of STN neurons in control rats and DRN-lesioned rats were (6.93+/-6.55) Hz and (11.27+/-9.31) Hz, respectively, and the firing rate of DRN-lesioned rats significantly increased when compared to the control rats (P<0.01). In control rats, 13% of STN neurons discharged regularly, 46% irregularly and 41% in bursts. In DRN-lesioned rats, 9% of STN neurons discharged regularly, 14% irregularly and 77% in bursts, the percentage of STN neurons firing in bursts was obviously higher than that of the control rats (P<0.01). In addition, the mean interspike interval coefficient of variation of STN neurons in control rats and DRN-lesioned rats were (0.05+/-0.04) and (0.11+/-0.09), respectively. The mean interspike interval coefficient of variation of DRN-lesioned rats was significantly higher than that of the control rats (P<0.001). These results show that the firing rate and the bursting pattern rate of neurons in STN of DRN-lesioned rats increase significantly, suggesting that DRN inhibits the neuronal activity of the subthalamic neurons in the intact rat.