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The populations infected with malaria have developed genetic defense mechanisms in order to protect themselves against the most serious complications of this disease. Those mechanisms have been associated from the perspective of co-adaptive process with some genetic diseases widely present in humans as sickle-cell disease, sickle cell trait and glucose-6-phosphate dehydrogenase deficiency (G6PD). Biochemically, polymorphic mutations at the erythrocyte level have been widely studied, however there is no clear statement of the mechanisms used for resistance against the causative agent of malaria. The purpose of this review is to introduce the molecular and biochemical basis of defense mechanisms associated with two of those adaptations: sickle-cell trait and Glucose-6-phosphate Dehydrogenase Deficiency (G6PD). The first one is a hemoglobinopathy while the second one is the most frequent enzymopathy present in humans.

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Skin cancer rates have increased worldwide despite the current prevention measures. It’s crucial to evaluate people’s knowledge, attitudes, and behaviour regarding sun exposure. Objective: To assess the knowledge and attitudes regarding sun exposure in the workers from primary health care. Method: 223 workers from three Family Care Centres(CESFAM) and from one Primary Emergency Service (SAPU) in the district of Recoleta were surveyed between the months of October and November 2015. Fisher’s exact test and Chi square test were used for statistic analysis. The survey included questions about demographic variables, knowledge of the association between sun radiation/skin cancer and attitudes towards sun protection. Results: the sample consists of 74 men and 149 women, with a mean age of 37 years ±SD 7.9. Phototype III was the most common (41.3percent). The majority of the surveyed declared to be aware of the association between sun exposure and skin cancer (93.3percent). As photoprotecting measures, sunscreens (87.4percent) and seeking shade (71.3percent) were the most frequently measures used. Regarding sunburns, 91.9percent declared to have at least one during their lifetime, 21.5percent occurring during the previous summer. As to the use of sunscreen, 42.1percent referred only using while at the pool / beach and 12.6percent declared not to use it at all. As for health promotion, 29.1percent declared they never recommend the use of sun protection measures in their working practice. Discussion: Although there is adequate knowledge regarding the effects of sun exposure, it doesn’t always reflect on favourable attitudes and photoprotecting measures. There was a significantly greater amount of females with adequate knowledge and use of sun protection measures. This study is one of the first to assess photoprotection behaviour in health care workers.

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El Síndrome de Buschke-Ollendorf es una rara entidad, descrita por primera vez en 1928. Se caracteriza por la asociación de nevos del tejido conjuntivo y osteopoiquilia. Es una patología de origen multifactorial. Causas genéticas han sido descritas. Dado que es una enfermedad benigna y que no se ha demostrado asociación con otras patologías, no requiere tratamiento y tiene buen pronóstico. Su importancia radica en el diagnóstico diferencial respecto de otras patologías complejas y severas. Se presenta el caso de una niña de 8 años de edad, que presenta desde los 2 años lesiones papulares en región glútea y zona lumbar izquierda, cuyo estudio histológico evidencia nevos de tejido conectivo. Presenta estudio radiológico que muestra la presencia de imágenes sugerentes de osteopoiquilia en fémur y cadera. La asociación de ambas entidades clínicas configura el diagnóstico de Síndrome de Buschke-Ollendorf. Se presenta el caso clínico y revisión de la literatura.

The Buschke-Ollendorf syndrome is a rare entity, first described in 1928 and is characterized by the association of connective tissue nevi and osteopoikilosis. It´s a disease of multifactorial origin. Genetic causes have been described. Since it is a benign disease and no association with other diseases have been proved, it doesn´t require treatment and has a good prognosis. It´s importance lies in the differential diagnosis with other complex and severe pathologies. We present the case of an 8-year-old girl with long lasting papular lesions in left buttock and lower back, which histological study showed connective tissue nevi. The radiological study showed suggestive images of osteopoikilosis in femur and hip. The association of both clinical entities suggest the diagnose of Buschke-Ollendorf syndrome. Clinical case and review of the literature is presented.

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Introducción. La pancreatitis aguda es una enfermedad poco frecuente en pediatría, y que no cuenta con un sistema adecuado para predecir gravedad. Objetivo: determinar las variables más frecuentes que se asocian a complicaciones de pancreatitis aguda en niños. Métodos. Se revisaron expedientes de pacientes menores de 17 años que fueron hospitalizados de enero de 2001 a diciembre de 2006 con pancreatitis aguda. Se analizaron sus características demográficas, la presencia o no de complicaciones, estado nutricional y tipos, y duración de intervenciones nutricionales. Resultados. De 181 expedientes revisados, 47 cumplieron con criterios de inclusión; 30% correspondieron al sexo masculino, con una media de edad de 8.7 ± 4 años. El peso para la talla fue de 106 ± 21% y el índice de masa corporal (IMC) de 17 ± 3 kg/ m² (zIMC: 0.031 ± 0.21), 13% de pacientes tuvieron sobrepeso, con un peso para la talla (P/T) mayor a 110%; 38% desarrollaron complicaciones y se registraron 2 muertes. Los pacientes con complicaciones vs los que no las tuvieron, mostraron diferencia en P/T, IMC y zIMC (P <0.01), pero no en otros parámetros medidos. El apoyo nutricio se inició en promedio a los 5.7 días con nutrición parenteral total en 89% de los casos, y la vía enteral a los 13 ± 10 días. Conclusiones. En nuestro estudio, casi la mitad de pacientes con pancreatitis aguda tuvo una enfermedad oncológica de base, y etiología farmacológica en 57% de los casos. De los factorespronósticos analizados, no hubo diferencia estadísticamente significativa en leucocitos séricos y en concentraciones plasmáticas de amilasa y lipasa entre pacientes con y sin complicaciones, y el mayor número de complicaciones de pancreatitis aguda se detectó en los pacientes con mayor P/T e IMC; esta asociación orienta al diseño de escalas pronósticas que incluyan estas variables.

Introduction. Acute pancreatitis is an uncommon disease in childhood that lacks an adequate scale for predicting disease severity. The objective of this study was to determine the main factors that predict severe acute pancreatitis. Methods. A chart review of children under 17 years of age hospitalized with diagnosis of acute pancreatitis from January 2001 to December 2006 was conducted. Demographics, local and systemic complications, nutritional status and nutritional support were analyzed. Results. Forty-seven patients were included with a mean age of 8.7 ± 4 years. Weight for height (W/H) was 106 ± 21% and BMI 17.3 kg/m² (zBMI 0.031 ± 0.21); 13% of patients were overweight, with W/H greater than 110%. Thirty-eight percent of patients developed complications; these patients, compared with patients without complications, showed a difference in W/ H, BMI and zBMI (P <0.01), but not in other parameters. Nutritional support started on average at 5.7 days with parenteral nutrition in 89% of cases, and enteral feeding after 13 ± 10 days of fasting. Conclusion. In our study, more than 50% of patients had oncological diseases, and 57% presented pharmacological etiology. Prognosis factors were analyzed and no statistical differences in serum leucocytes, amylase and lipase were found between patients with or without complications; most complications were found in patients with higher W/H and BMI. This association suggests that future prognosis scales of acute pancreatitis in children should include these variables.

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Delayed Hypoxic-isquemic Leucoencephalopathy described in 1976 by Ginsberg is a brain white matter demyelinization phenomenon that occurred days or weeks after a hypoxic-isquemic injury followed by a complete recovery of the episode. The pathogenesis process remains unknown. We describe a 48 year old woman with cervico-uterine cancer in palliative treatment with opoids. She enters the emergency room with a respiratory depression, a prolonged hypotension and confusion, that it was recovered. At admission exhibits a recurrent pneumonia. Two weeks later, in conditions of discharge, initiates with agitation in context with rapidly progressive decline cognition, with concordant lesions of Leucoencephalopathy defined in the Magnetic Resonance (MR) study The metabolic profile, the cerebrospinal fluid and the electroencephalogram allowed dismissing other etiologic hypothesis. In front to the suspicious of Ginsberg syndrome, she had normal levels of Arylsulfatase. This acute post-hypoxic demyelinization process has been pathogenic interpreted as an arylsulfatase deficiency. Although numerous cases develop with normal arylsulfatase and the experimental studies of hypoxia, has support the hypothesis of a central hypoxic axonopathy due to failing in axonal transport as the base of the demyelinization phenomenal.

La leucoencefalopatía hipóxico-isquémica retardada (EHIR), descrita por Ginsberg en el año 1976, es un fenómeno desmielinizante de la sustancia blanca cerebral, que se origina días o semanas después de un daño hipóxico-isquémico que había sido seguido de una recuperación completa del episodio. La patogenia del proceso no está completamente establecida. Se presenta una mujer de 48 años portadora de cáncer cérvicouterino, en tratamiento paliativo con opiáceos. Ingresa al Servicio de Urgencia por una depresión respiratoria, hipotensión prolongada y compromiso de conciencia, donde es recuperada. Se hospitaliza por una neumopatía intercúrrente. Dos semanas más tarde, estando en condiciones de alta, se inicia agitación psicomotora en el contexto de un deterioro cognitivo rápidamente progresivo, que el estudio de Resonancia Magnética (RM) definió como lesiones concordantes con una leucoencefalopatía. El perfil metabólico, el líquido cefalorraquídeo y el electroencefalograma, permitieron descartar otras hipótesis etiológicas. Frente a la sospecha de un síndrome de Ginsberg, los niveles de arilsulfatasa fueron normales. Este proceso desmielinizante agudo post-hipóxico, ha sido interpretado patogénicamente como un déficit de arilsulfatasa. Sin embargo, la existencia de numerosos casos que cursan con arilsulfatasa normal y los estudios experimentales de hipoxia, ha avalado la hipótesis de una axonopatía central hipóxica, atribuible a fallas del transporte axoplásmico, como base para el fenómeno desmielinizante.

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Lance-Adams syndrome was described in 1963 is a rare complication due to recovered hypoxic episodes or prolonged hypotension events. Is characterized by action myoclonus and cerebellar ataxia. We report two patients studied with this syndrome. A 51 year-old men and a 72 years-old men fully recovered after a brief cardiorespiratory arrest they developed intention myoclonus, triggered by voluntary movements, posture, also by sounds, touches and emotional stimuli. It also was accompanied by cerebellar syndrome, ataxia and posture control alterations. They had a Magnetic Resonance (MR), EEG and normal metabolic parameters. Myoclonus was treated with sodium valproate and clonazepam. The neurophysiologic interpretation of this motor imbalance is an abnormal functioning of the Central Pattern Generator Netwoks (CPGN) located in the mesencephalic region. Hypoxic lesions in vermian purkinje and paravermal cerebellum neurons have an inhibitory effect in this system, producing motor control attenuation, generating an imbalance in the motoneurons of the spinal cord contraction sequence, which starts shooting in an uncoordinated way. As in almost all cerebellar lesions with time they tend to compensate and to diminish myoclonus.

El Síndrome de Lance-Adams descrito en 1963, es una rara complicación que sigue tardíamente a episodios hipóxicos o de hipotensión prolongada, ya recuperados. Se caracteriza por mioclonías de acción y ataxia cerebelosa. Se describen dos pacientes estudiados con este síndrome. Son dos hombres de 51 y 72 años que después de un paro cardiorrespiratorio breve, de recuperación completa, iniciaron mioclonías de intención, activadas por movimientos voluntarios, posturas, estímulos sonoros, táctiles y afectivos. Acompañado además de un síndrome cerebeloso, ataxia de la marcha y alteraciones del control postural. Cursaron con RM (Resonancia Magnética), EEG (Electroencefalograma) y parámetros metabólicos sin relevancia patológica. Las mioclonías fueron controladas con ácido valproico y clonazepam. La interpretación neurofisiológica de este desajuste motor es la alteración en el funcionamiento del patrón central de circuitos generadores (PCCG) ubicado en la región mesencefálica. Las lesiones hipóxicas de las neuronas de Purkinje del vermis y paravermianas del cerebelo, que tienen un efecto inhibitorio para este sistema, producen una atenuación del control motor del PCCG, generando desajuste en la secuencia de la contracción de las motoneuronas de la médula espinal, que comienzan a dispararse de manera independientemente. Como ocurre con la mayoría de las lesiones cerebelosas, con el tiempo tienden a compensarse y por consiguiente a disminuir las mioclonías.

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MELAS is an acronym for the convergence of mitochondrial myopathy, encephalopathy lactic acidosis and stroke like episodes. It was described by Pavlakis et al. in 1984.This is a genetic disease caused by mutations in the maternal mitochondrial genome, affecting the adenosine triphosphate (ATP) synthesis. The mutations have heteroplasmic loads on different tissues, which could specially involve those highly energy-dependent such as muscles, brain and CNS tissues. We describe a 33 year old female presenting migraine headaches associated to stroke-like episodes, related to an infection. Neurological manifestations include language and visual disturbances. The magnetic resonance imaging (MRI) showed low-intensity areas, predominantly in the temporal, parietal and occipital left lobes. She further presented a status epilepticus. The complementary study shows elevated basal and post exercise lactic acidosis, ragged red fibers in the muscle biopsy, and the mutation of A3243G in the mitochondrial genome. Her asymptomatic mother and sister showed ragged red fibers in muscle biopsy. The patient showed clinical and radiological features improvement, maintaining non epileptic slow focal occipital discharges in the electroencephalogram. The assumption is that this mitochondrial disorder could be more frequent than detected in our medium, given that a significant number of women could be just asymptomatic bearers (Like the patient's mother and sister). This pathology should always be assessed in patients less than 40 years of age with strokes, regardless whether they have family history with the disease.

MELAS es un acrónimo inglés que define la convergencia de miopatía mitocondrial, encefalopatía, acidosis láctica y episodios de pseudo-infarto cerebral, descrita por Pavlakis et al, en 1984. Es una enfermedad mitocondrial originada por mutaciones en el genoma mitocondrial materno. Se afectan las funciones aeróbicas como consecuencia del déficit que se produce en la generación de adenosina trifosfato (ATP). El compromiso de los distintos tejidos es variable, debido a la heteroplasmia de la mutación, aunque preferentemente se suelen dañar el tejido muscular y el sistema nervioso central, tejidos con mayores requerimientos energéticos. Presentamos una paciente de 33 años que inicia su enfermedad con un síndrome jaquecoso, seguido de un episodio de pseudo infarto cerebral, en relación a un cuadro infeccioso. Clínicamente, evolucionó con alteraciones visuales y del lenguaje que eran concordantes con las áreas de hipointensidad en ambas cortezas temporales y en la corteza del lóbulo parietal y occipital izquierdo, vistas en la Resonancia Magnética. Varios días después de su ingreso cursó con un estatus epiléptico. Su estudio demostró aumento de la lactoacidemia de reposo (39,7) y de esfuerzo (89,4). En la biopsia muscular se observó la presencia de fibras rojas raídas, al igual que en su madre y hermana menor, ambas asintomáticas. El análisis genético demostró la presencia de la mutación A3243G del genoma mitocondrial, estimada en un 26 por ciento del total. La paciente mejoró espontánea y completamente en lo clínico y radiológico, sólo mantuvo una actividad lenta occipital izquierda, de carácter no epiléptico. Se presume que esta alteración mitocondrial podría ser más frecuente de lo detectado en nuestro medio, porque numerosas mujeres podrían ser sólo portadoras asintomáticas (como la madre y hermana de la paciente). Es una patología que debiera investigarse siempre en los accidentes vasculares de jóvenes menores de 40 años, aunque no tengan antecedentes familiar.

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ANTECEDENTES: El embarazo está contraindicado en toda paciente con hipertensión pulmonar, y particularmente en aquellas con síndrome de Eisenmenger. OBJETIVO: Describir 3 casos de embarazadas con síndrome de Eisenmenger, tratadas con sildenafil. RESULTADOS: El desarrollo del embarazo se complicó en las tres pacientes con parto prematuro, a las 30, 28 y 35 semanas, respectivamente. En 2 pacientes el parto se resolvió mediante operación cesárea. No hubo mortalidad materna ni perinatal. CONCLUSIÓN: El síndrome de Eisenmenger es de alto riesgo de morbimortalidad materno-perinatal y el manejo multidisciplinario optimiza los resultados. Se describe el uso de sildenafil.

BACKGROUND: Pregnancy in contraindicated in patient with pulmonary hypertension, especially in dose with Eisenmenger syndrome. OBJECTIVE: To present 3 cases of pregnancy in patients with Eisenmenger syndrome treated with sildenafil. RESULTS: The pregnancy becomes complicated in the 3 cases, with premature delivery at 30, 28 and 35 weeks respectively. Cesarean delivery was performed in two cases. There was no maternal or perinatal mortality. CONCLUSION: The Eisenmenger syndrome is a high risk condition of maternal-perinatal morbimortality and the multidisciplinary handling optimizes the results. The sildenafil use is described.

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National and international environmental tobacco smoke studies were reviewed regarding its effects on passive smokers' health. Environmental tobacco smoke is composed by more than 4,000 known substances, which are different if they are in the mainstream or sidestream. Studies with biomarkers like cotinine have concluded that exposed nonsmokers have an increased cardiovascular morbi-mortality. Passive smokers also have an increased risk of lung, nasal sinus and breast cancer. Children have more acute and chronic respiratory symptoms, low respiratory infections, otitis and sudden infant death syndrome. Environmental tobacco smoke induces asthma and causes exacerbations in both children and adults. In reproductive health, it decreases the age of menopause and produces menstrual disorders. Newborn infants of passive smoking mothers have a higher probability of low birth weight and to be small for gestational age. This international scientific evidence should lead countries to take measures in order to protect nonsmokers' health.

Se realizó una revisión de los estudios nacionales e internacionales sobre los efectos del humo de tabaco ambiental en la salud de los fumadores pasivos. El humo de tabaco ambiental está conformado por más de 4.000 sustancias químicas, las que difieren cuali y cuantitativamente al estar presentes en la corriente principal o en la lateral. Los no fumadores expuestos presentan un aumento de morbi-mortalidad por enfermedad cardiovascular, incluso con estudios con biomarcadores como cotinina. Además los fumadores pasivos tienen un riesgo aumentado de presentar cáncer de pulmón, de senos paranasales y mama. En niños existe un mayor número de síntomas respiratorios agudos y crónicos, infecciones respiratorias bajas, otitis media y síndrome de muerte súbita infantil. El humo de tabaco ambiental favorece la inducción y exacerbación de asma bronquial en niños y adultos. En la salud reproductiva, disminuye la edad de aparición de la menopausia y produce desórdenes menstruales. Los recién nacidos hijos de madres fumadoras pasivas tienen mayor probabilidad de nacer con bajo peso o de ser pequeños para la edad gestacional. La evidencia científica internacional debe contribuir a que los países tomen medidas para proteger la salud de los no fumadores.

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The ability of dipyridamole (DIP) to scavenge oxygen metabolites generated by either activated human neutrophils (PMNs) or cell-free systems using luminol(s)- and lucigenin-enhanced chemiluminescence was investigated. In the presence of DIP (15-50 microM) a dose-dependent inhibition period was seen in phorbol myristate acetate (PMA)-stimulated PMNs as assayed by isoluminol-enhanced chemiluminescence (ILCL) with horseradish peroxidase (HRP). Although such a lag period was not observed in the absence of HRP, 50 microM DIP inhibited extracellular ILCL by more than 50%. Intracellular luminol-enhanced chemiluminescence (LCL) as assayed in either PMA- or in ionomycin-activated PMNs was not affected by dipyridamole (15-50 microM). In cell-free systems, DIP produced concentration-dependent inhibition in H2O2-(45% at 50 microM), OH- (40%, at 0.1 microM) and HOCl-(20% at 10 microM). Both absorbance and fluorescence scans revealed that DIP is able to react with equimolar quantities of either H202 or HOCl. These results suggest that DIP scavenges reactive oxygen species (ROS) presumably secreted by activated human PMNs in the following decreasing order: *OH > HOCl > H2O2 >> O2-.

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Presentamos la experiencia y evolución del parto instrumentado en nuestro Servicio de Obstetricia y Ginecología, en los últimos once años 1992-2002. La evidencia demostró que respecto de las lesiones maternas y fetales, las Espátulas (ET), o instrumento no articulado de la clasificación general de los fórceps (F), son significativamente menores cuando se las compara con el fórceps articulado y fenestrado de Kjelland o Kielland (FK), por lo que se sugiere su conocimiento y adiestramiento en los Servicios de la especialidad, y cambiar el concepto de la presa del cráneo-fetal o biparieto malar por la toma libre facio malar.

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En el Centro de Rehabilitación de COANIQUEM en Santiago de Chile ingresaron en 1998 3 245 niños, de los cuales 213 niños sufrieron quemaduras originadas por el volcamiento de una cocina (VC). Se evaluó la incidencia de VC, las características de los afectados, la gravedad de las lesiones y se compararon con los 3032 pacientes restantes (C). Resultados: VC correspondió al 6.6 por ciento de los pacientes. Fueron varones 70,9 por ciento en VC y 52,2 por ciento en C (p NS); tenían menos de 2 años 83,1 por ciento en VC 46 por ciento en C (p 0,0114). Tenían lesiones múltiples 67,7 por ciento de niños VC y 32,6 por ciento de C (p < 0.001); se afectaron con mayor frecuencia las extremidades inferiores en VC (35,4 por ciento) y las superiores en C (46,7 por ciento). Requirieron hospitalización previa o posterior al ingreso 39,9 por ciento en VC y 11,7 por ciento en C (p < 001). La profundidad de las quemaduras hizo necesaria una intervención quirúrgica en 54,5 por ciento de los afectados por VC y en 22,6 por ciento de C. De 117 casos VC hospitalizados u operados 60,7 por ciento permanecía en tratamiento de rehabilitación al año de evolución vs 27,7 por ciento de C. Conclusión: El volcamiento de cocina ocasiona un número considerable de quemaduras, especialmente en niños de 1 a 2 años, cuya gravedad (mayor hospitalización y necesidad de injertos) aconseja medidas de prevención y mejoría en las característica de estos artefactos

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A case of lice infestation of the hair in a 24 year-old man was reported. After the entomological identification of adults and immature stages of the vector; it was confirmed that the only existing parasite was Phtihirus pubis Linnaeus 1758, a hematophagous insect that usually infests pubis, armpit, eyelids, and other parts of the body but is rarely found in the head.

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The side effects of lindane in children with pediculosis were reported. 2.54% of the 551 primary school children who underwent treatment had adverse reactions to this drug. It was recommended to increase knowledge about this parasitization and to avoid the indiscriminate use of chemicals and other products to eliminate lices.

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Laboratory studies and field observations in relation to the preference of Mansonia titillans (Diptera: Culicidae) to for oviposition over certain plants in 3 hatcheries of Havana Province (Bauta and Batabanó) and Havana City (Parque Lenin) were carried out. In the laboratory, the great number of ovipositions was found to occur under the leaves of plants such as Spirodela polirhiza, while under natural conditions it was observed that this can occur in egg hatcheries whenever Eicchornia sp is present, because these plants protect the eggs and provide adequate conditions for the larvae to complete the cycle of life in the roots.

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No encontramos yodo al analizar doce muesras diferentes de sal que consume la población. Tres de estas muestras proceden de las minas de sal de Montecristi, Barahona y Baní, las restantes se venden en el mercado como "sal yodada". El 56 por ciento de las madres usan sal en grano para preparar sus alimentos y de un 16-44 por ciento relacionó el yodo a la aparición de Bocio

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By means of starch gel electrophoresis, samples were analyzed from 3 populations (Batabanó, Guanímar and Isle of Youth) of Cubanichthys cubensis adult fishes, bioregulators of mosquito larvae. A study was made of six protein systems which are considered to be under the genetic regulation of 13 loci, 3 of which are polymorphic. The electrophoretic characteristics of each of them are described. By means of the genotypical frequencies of the polymorphic systems (PGI-1, PGI-2, and PGM), the 3 populations were compared with the use of the statistical G. No significant differences were found.

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A study was carried out in order to determined the larval population density of Culex nigripalpus, vector of different parasitic and viral diseases in the neotropical region. Two population from Havana and Havana City Provinces were studied during the period comprised between November 1986 and November 1987. The higher densities of this species appeared during December 1986 (838.2 larvae/m2) and November 1987 (495 larvae/m2) in Santa Cruz del Norte (Havana) and in November 1986 (343.2 larvae/m2), January 1987 (232.65 larvae/m2), February 1987 (580.8 larvae/m2) in the Lenin Park (Havana City).

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Insulin resistance in uremia has been attributed to impaired hormone-receptor binding or to postbinding defects. Oral glucose tolerance tests, insulin binding, and in vitro glycolytic activity were studied in purified red blood cells from normal control subjects (C) and from uremic patients belonging to three groups: nondialyzed (U), on chronic hemodialysis (HD), and on continuous ambulatory peritoneal dialysis (CAPD). Glucose intolerance and hyperinsulinemia were demonstrated in all groups of patients. Maximal specific binding of 125I-insulin to erythrocytes, kinetically derived receptor numbers per cell, and affinity constants for insulin binding did not differ between control and patient groups. No correlation was found between the degree of glucose intolerance and insulin binding parameters. Basal lactate production by erythrocytes incubated in vitro was significantly higher in U and HD patients than in C, whereas CAPD patients did not differ from C in this respect. Addition of 1 mM dibutyryl-cAMP and 0.5 mM isobutyl-methyl-xanthine during incubation of erythrocytes caused an increase in the rate of lactate production that was similar in magnitude in the U, HD and C groups, whereas cells from CAPD subjects showed a significantly larger absolute response to these compounds after 1 h of incubation. There was no evidence of impairment of glycolytic capacity in red blood cells from uremic patients. In addition, no correlation was found between the degree of glucose intolerance and basal or stimulated lactate production by erythrocytes. Our results obtained in human erythrocytes suggest that the insulin resistance observed in uremia does not involve a defect in hormone binding or in the intracellular capacity to utilize glucose through glycolysis.

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