[Analysis of causes and factors associated with hospital readmission in mild and moderate polythraumatism: An observational study]. / Análisis de las causas y los factores asociados al reingreso hospitalario en politraumatismo leve-moderado: estudio observacional.

BACKGROUND: Early readmissions (ER) occur during the 30 days after discharge, ER are common and expensive, associated with a decrease in the quality of care. The rate of ER in polytraumatic patients (PTP) is estimated between 4.3-15%. Our objective was to identify those factors associated with ER and its characteristics after suffering mild-moderate trauma in our area. MATERIAL AND METHOD: This is a retrospective observational study, including data of patients with (PTP) mild or moderate admitted between July 2012 and June 2017 in our institution and their ER in public hospitals and/or outpatient centers. Demographic variables, diagnoses, procedures and characteristics of readmissions were collected. After a bivariant analysis was done, a Logistic regression had benn performed to determine risk factors for ER. RESULTS: 1013 patients were included, with median age of 38 years, ISS of 3 points and initial hospital stay of 1 day. 185 patients were readmitted (18.3%). Independent factors associated with ER were: injury mechanism, especially bicycle accident (OR 2.26), comorbidities highlighting HBP (OR 1.83) and COPD (OR 1.98), fracture immobilization (OR 1.99) and hospital admission in the initial care (OR 0.56). The causes of ER were: pain 61.6%, wound infection 15.1%, scheduled cures and deferred interventions 12.97%, medical 6.4% and psychiatric decompensation. 2.7% CONCLUSION: The ERs in mild-moderate PTP are multifactorial, our results show an association between factors such as injury mechanism, the presence of comorbidities and the procedures performed in the sentinel episode and the rate of ER. The implementation of simple interventions at discharge could reduce its incidence clearly.

Technovigilance and risk management as tools to improve patient safety in colombian health care institutions / La tecnovigilancia y la gestión de riesgos como herramientas para mejorar la seguridad de los pacientes en las instituciones de salud colombianas / A tecnovigilância e a gestão de riscos como ferramentas para melhorar a segurança dos pacientes nas instituições de saúde colombianas

This paper presents the results of a survey about technovigilance carried out in 21 clinical institutions from the southwest of Colombia. It also provides an analysis of how these programs take into account different risk management methodologies in order to create awareness of the importance of patient safety in all members of the staff and improve the quality of the health services provided.

Este trabajo presenta los resultados de una encuesta acerca de la vigilancia tecnológica llevada a cabo en 21 instituciones de salud del suroeste de Colombia. Adicionalmente proporciona un análisis de cómo estos programas consideran diferentes metodologías de manejo de riesgos para crear conciencia en todos los empleados de la importancia de la seguridad de los pacientes y así mejorar la calidad de los servicios de salud prestados.

Este trabalho apresenta os resultados de uma pesquisa a respeito da vigilância tecnológica levada a cabo em 21 instituições de saúde do sudoeste da Colômbia. Adicionalmente proporciona uma análise de como estes programas consideram diferentes metodologias do controle de riscos para criar consciência em todos os empregados da importância da segurança dos pacientes e assim melhorar a qualidade dos serviços de saúde emprestados.

Resistance to Crown and Root Rot Caused by Phytophthora capsici in a Tomato Advanced Backcross of Solanum habrochaites and Solanum lycopersicum.

Phytophthora capsici causes devastating disease on many vegetable crops, including tomato and other solanaceous species. Solanum habrochaites accession LA407, a wild relative of cultivated tomato, has shown complete resistance to four P. capsici isolates from Michigan cucurbitaceous and solanaceous crops in a previous study. Greenhouse experiments were conducted to evaluate 62 lines of a tomato inbred backcross population between LA407 and the cultivated tomato 'Hunt 100' and 'Peto 95-43' for resistance to two highly virulent P. capsici isolates. Roots of 6-week-old seedlings were inoculated with each of two P. capsici isolates and maintained in the greenhouse. Plants were evaluated for wilting and plant death three times per week for 5 weeks. Significant differences were observed in disease response among the inbred tomato lines. Most lines evaluated were susceptible to P. capsici isolate 12889 but resistant to isolate OP97; 24 tomato lines were resistant to both isolates. Heritability of Phytophthora root rot resistance was high in this population. Polymorphic molecular markers located in genes related to resistance and defense responses were identified and added to a genetic map previously generated for the population. Resistant lines and polymorphic markers identified in this study are a valuable resource for development of tomato varieties resistant to P. capsici.

Factors related to dental caries in adolescents in southeastern Brazil.

AIM: Identify the experience of dental caries among adolescents associated to work, self-care, social life and access to healthcare services. MATERIALS AND METHODS: This cross-sectional study was carried out with 60 adolescents aged 15 and 16 years in a city in southeastern Brazil. The data were collected through a structured interview and clinical exam for dental caries carried out by a single, duly calibrated examiner (Kappa=0.8 to 0.9). The relationships between the dependent variable (experience of dental caries) and independent variables (work, self-care, social life and access to healthcare services) was determined using bivariate (chi square test, p<0.10) and multivariate analysis (p<0.25). RESULTS: Eighty percent had two or more teeth with caries (95% CI: 70.0-90.0). Mean DMFT was 4.72 (± 3.55) and DMFS was 8.07 (± 7.46). When the experience of caries was related to the independent variables, only access to healthcare services achieved statistical significance. Individuals with greater access had a threefold greater chance of belonging to the group with a lesser experience with caries, PR=3.2 (90% CI 1.07-9.78). CONCLUSION: All interviewees reported seeking care in the private system when requiring dental assistance. Access to healthcare (declared as essentially private) was associated to dental caries.

The glucose-lowering agent sodium tungstate increases the levels and translocation of GLUT4 in L6 myotubes through a mechanism associated with ERK1/2 and MEF2D.

AIMS/HYPOTHESIS: The aim of this study was to investigate the action of the glucose-lowering compound sodium tungstate on glucose transport in muscle myotubes and to unravel the molecular events underlying the effects observed. METHODS: We studied the effects of tungstate on 2-deoxy-D: -glucose uptake, levels and translocation of the glucose transporters GLUT4 and GLUT1, and Glut4 (also known as Slc2a4) promoter activity. We also measured the modifications of individual components of the signalling pathways involved in the effects observed. RESULTS: Tungstate increased 2-deoxy-D: -glucose uptake in differentiated L6 myotubes through an increase in the total amount and translocation of GLUT4 transporter. The effects on glucose uptake were additive to those of insulin. Tungstate activated transcription of the Glut4 promoter, as shown by an increase in Glut4 mRNA, and by a promoter reporter assay. The assay of deletions of the Glut4 promoter indicated that the effect of tungstate is mediated by the myocyte enhancer factor 2 (MEF2)-binding domain. Accordingly, MEF2 levels and DNA binding activities were increased in response to the treatment. Tungstate-induced glucose uptake and GLUT4 transcriptional activation were dependent on the activation of extracellular signal-regulated kinases 1 and 2 (ERK1/2), while no changes were observed in the phosphorylation state of the beta subunit of the insulin receptor, in the phosphatidylinositol 3-kinase pathway or in the activation of 5'AMP-activated protein kinase. CONCLUSIONS/INTERPRETATION: Tungstate activates glucose uptake in myotubes through a novel ERK1/2-dependent mechanism. This effect is exerted by an increase in the content and translocation of the GLUT4 transporter. This is the first report of a glucose-lowering compound activating Glut4 transcription through an ERK1/2-dependent increase in MEF2 levels.

First Report of Late Blight Caused by Phytophthora infestans on Cape Gooseberry (Physalis peruviana) in Colombia.

Late blight caused by Phytophthora infestans is the most limiting disease for several species of the Solanaceae family in Colombia. A potential host for P. infestans is Cape gooseberry (Physalis peruviana), a species belonging to the Solanaceae family. Its center of origin is the highlands of Peru and it is grown at approximately 1,500 to 3,000 m above sea level. Cape gooseberry has become an important export fruit in Colombia. Consequently, in the last few years, the area cultivated with Physalis peruviana has increased dramatically. P. infestans was isolated from this crop in the province of Cundinamarca, Colombia. Symptoms caused by this oomycete appeared initially on the leaf margins as small, irregular, necrotic spots that expanded and merged, increasing the necrotic area. These spots had a soft texture resulting from the degradation of plant tissue by the pathogen. On old lesions, white mycelia and sporangia were observed. Affected plants were rarely killed, but under favorable conditions, severe symptoms were observed in leaves and yield was reduced. Ten isolates were obtained from infected tissue by placing a lesion directly on a potato slice in a moist chamber (2). Mycelia grown on the potato slice were then transferred to rye agar. Identification of the pathogen was performed based on morphological characteristics, specifically, sporangiophores of P. infestans are compoundly branched and develop sympodially, with swellings at the points where sporangia were attached (1). Further confirmation was obtained by sequencing the internal transcribed spacer (ITS) regions (GenBank Accession Nos. EF173467-EF173476). Koch's postulates were completed in the laboratory by spray inoculating detached leaves of Cape gooseberry with a zoospore suspension obtained from each of the 10 isolates. Inoculum was prepared by flooding 10-day-old cultures with sterile distilled water to obtain a 104/ml sporangial suspension followed by zoospore induction at 4°C. Leaves were sprayed with this suspension, placed in moist chambers, and incubated at 20°C in the dark. Control leaves were sprayed with sterile distilled water. Two separate leaves were inoculated with each isolate. The pathogen was reisolated from leaf lesions in all cases. The period between infection and the appearance of symptoms ranged from 5 to 7 days. To our knowledge, this is the first report of P. infestans causing damage on Cape gooseberry in Colombia. Chemical control measures are to some extent successfully applied in most regions where solanaceous crops are grown in Colombia. Nevertheless, suitable disease management for Physalis peruviana has not been achieved and further studies on the epidemiology of the disease on this new host are needed. References: (1) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society. St. Paul, MN, 1996. (2) G. A. Forbes et al. Phytopathology 87:375, 1997.

Abnormal subcellular distribution of GLUT4 protein in obese and insulin-treated diabetic female dogs.

The GLUT4 transporter plays a key role in insulin-induced glucose uptake, which is impaired in insulin resistance. The objective of the present study was to investigate the tissue content and the subcellular distribution of GLUT4 protein in 4- to 12-year-old control, obese and insulin-treated diabetic mongrel female dogs (4 animals per group). The parametrial white adipose tissue was sampled and processed to obtain both plasma membrane and microsome subcellular fractions for GLUT4 analysis by Western blotting. There was no significant difference in glycemia and insulinemia between control and obese animals. Diabetic dogs showed hyperglycemia (369.9 +/- 89.9 mg/dl). Compared to control, the plasma membrane GLUT4, reported per g tissue, was reduced by 55% (P < 0.01) in obese dogs, and increased by 30% (P < 0.05) in diabetic dogs, and the microsomal GLUT4 was increased by approximately 45% (P < 0.001) in both obese and diabetic animals. Considering the sum of GLUT4 measured in plasma membrane and microsome as total cellular GLUT4, percent GLUT4 present in plasma membrane was reduced by approximately 65% (P < 0.001) in obese compared to control and diabetic animals. Since insulin stimulates GLUT4 translocation to the plasma membrane, percent GLUT4 in plasma membrane was divided by the insulinemia at the time of tissue removal and was found to be reduced by 75% (P < 0.01) in obese compared to control dogs. We conclude that the insulin-stimulated translocation of GLUT4 to the cell surface is reduced in obese female dogs. This probably contributes to insulin resistance, which plays an important role in glucose homeostasis in dogs.

Abnormal subcellular distribution of GLUT4 protein in obese and insulin-treated diabetic female dogs

The GLUT4 transporter plays a key role in insulin-induced glucose uptake, which is impaired in insulin resistance. The objective of the present study was to investigate the tissue content and the subcellular distribution of GLUT4 protein in 4-to 12-year-old control, obese and insulin-treated diabetic mongrel female dogs (4 animals per group). The parametrial white adipose tissue was sampled and processed to obtain both plasma membrane and microsome subcellular fractions for GLUT4 analysis by Western blotting. There was no significant difference in glycemia and insulinemia between control and obese animals. Diabetic dogs showed hyperglycemia (369.9 ± 89.9 mg/dl). Compared to control, the plasma membrane GLUT4, reported per g tissue, was reduced by 55 percent (P < 0.01) in obese dogs, and increased by 30 percent (P < 0.05) in diabetic dogs, and the microsomal GLUT4 was increased by approximately 45 percent (P < 0.001) in both obese and diabetic animals. Considering the sum of GLUT4 measured in plasma membrane and microsome as total cellular GLUT4, percent GLUT4 present in plasma membrane was reduced by approximately 65 percent (P < 0.001) in obese compared to control and diabetic animals. Since insulin stimulates GLUT4 translocation to the plasma membrane, percent GLUT4 in plasma membrane was divided by the insulinemia at the time of tissue removal and was found to be reduced by 75 percent (P < 0.01) in obese compared to control dogs. We conclude that the insulin-stimulated translocation of GLUT4 to the cell surface is reduced in obese female dogs. This probably contributes to insulin resistance, which plays an important role in glucose homeostasis in dogs.

Modulation of glucose transporters in rat diaphragm by sodium tungstate.

Oral administration of sodium tungstate is an effective treatment for diabetes in animal models. We examined the effects of 6 weeks of oral administration of tungstate on glucose transporters (GLUT) in streptozotocin-induced diabetic rat diaphragm. Diabetes decreased GLUT4 expression while tungstate treatment normalized not only GLUT4 protein but also GLUT4 mRNA in the diabetic rats. Furthermore, treatment increased GLUT4 protein in plasma and internal membranes, suggesting a stimulation of its translocation to the plasma membrane. Tungstate had no effect on healthy animals. There were no differences in the total amount of GLUT1 transporter in any group. We conclude that the normoglycemic effect of tungstate may be partly due to a normalization of the levels and subcellular localization of GLUT4, which should result in an increase in muscle glucose uptake.

[Correlation between subjective and objective health measurements in patients with chronic obstructive pulmonary disease (COPD)]. / Correlación entre medidas de salud subjetivas y objetivas en pacientes con enfermedad pulmonar obstructiva crónica (EPOC).

AIMS: Analyze the relation between objective health assessment (OHA) -Forced spirometry- and subjective health assessment (SHA) -quality of life- in patients with chronic obstructive pulmonary disease (COPD). Analyze the correlation between two different questionnaires to assess quality of life. DESIGN: Cross-sectional study. PARTICIPANTS: 278 patients with COPD (confidence level 95%) from two urban health centers. MAIN MEASUREMENTS: Personal interview. VARIABLES: quality of life (Nottingham Health Profile; St George Respiratory Questionnaire); sociodemographic profile; diagnose of COPD; comorbidity; recent spirometry. STATISTICAL ANALYSES: Descriptive statistics; test ji-squared, Kruskal-Wallis and the correlation coefficient. RESULTS: Age: 66,9 years; sex: 88% male. Quality of life scales (mean and confidence intervals): Nottingham Health Profile subscales (total score 100 points): energy 40 (35.6-44.4), pain 35.9 (32.3-39.5), emotional reactions 32.5 (29.4-38.6), sleep 41.9 (37.8-45.9), social isolation 15.3 (12.7-17.9), mobility 36.7 (33.9-39.5) and global score 33.4 (30.8-36). St George Respiratory Questionnaire subscales (total scores 100 points): impact 38.01 (35.08-40.18), activity 53.8 (50.2-57.4), symptoms 37.7 (35.2-40.3) and global score 40.0 (38.6-43.2). The correlation coefficients between the two questionnaires ranged between 0.12 (for the sleep and symptoms dimensions: p = 0.03) and 0.66 (for the mobility and activity dimensions; p < 0.0001). There is a positive lineal relation between the two questionnaires and the spirometric stages of COPD (measured by the maximum respiratory volume in the first second). CONCLUSIONS: We found a good correlation between the two quality of life questionnaires, but St George was more specific for respiratory illness. There is a mild-light correlation between objective and subjective health assessment in patients with COPD.

Correlación entre medidas de salud subjetivas y objetivas en pacientes con enfermedad pulmonar obstructiva crónica (EPOC) / Correlation between subjective and objective health measurements in patientes with chronic obstructive pulmonary disea (COPD)

Objetivos. Analizar la relación entre medidas de salud objetivas (espirometría actual) y medidas de salud subjetivas (calidad de vida autopercibida). Evaluar la correlación entre 2 cuestionarios de valoración de calidad de vida. Diseño. Descriptivo, transversal. Emplazamiento. Dos centros de salud urbanos con programa de crónicos (subprograma de enfermedad pulmonar obstructiva crónica [EPOC]).Participantes. Un total de 278 pacientes diagnosticados de EPOC. Mediciones principales. Mediante entrevista personal se analizan las siguientes variables: calidad de vida autopercibida (perfil de salud de Nottingham; cuestionario respiratorio St. George; rangos de puntuación de subescalas 0-100 puntos; perfil sociodemográfico, diagnóstico de EPOC, antecedentes personales, espirometría actual. Resultados. Edad, 66,9 ñ 8,9 años; género, 88 por ciento varones. Los principales resultados de salud autopercibida fueron (medias e IC del 95 por ciento): perfil de salud de Nottingham: subescalas de energía, 40 (35,6-44,4); dolor, 35,9 (32,3-39,5); emotividad, 32,5 (29,438,6); sueño, 41,9 (37,8-45,9); social, 15,3 (12,7-17,9); movilidad, 36,7 (33,9-39,5), y total, 33,4 (30,8-36). Cuestionario de St.George: subescalas de impacto, 38,01 (35,0840,18); actividad, 53,8 (50,2-57,4) síntoma, 37,7 (35,2-40,3) y total, 40,9 (38,6-43,2).Los coeficientes de correlación entre ambos cuestionarios oscilaron entre 0,12 (para las dimensiones sueño y síntoma; p = 0,03) y 0,66 (entre las dimensiones de movilidad y actividad; p < 0,0001). Existe una relación lineal de tendencia positiva entre ambos cuestionarios y las categorías de valores (normal, leve, moderado y grave) del parámetro espirométrico, volumen espiratorio máximo en el primer segundo (p < 0,0001).Conclusiones. Encontramos una buena correlación entre ambos cuestionarios de salud autopercibida, siendo de mayor especificidad para patología respiratoria el St. George. Existe una correlación levemoderada entre las medidas de salud objetivas y subjetivas en los pacientes con EPOC en nuestro medio. (AU)

Salud autopercibida, apoyo social y familiar de los pacientes con enfermedad pulmonar obstructiva crónica / Quality of life, familiar and social network of patients with chronic obstructive pulmonary disease

Fundamentos: la EPOC es una enfermedad crónica e invalidante con gran repercusión en la calidad de vida del paciente así como en su dinámica familiar y social. La percepción por parte del paciente de sus limitaciones genera un sentimiento de baja autoestima que pone en peligro su posición ante la familia y la sociedad. Objetivos: describir características sociodemográficas y conocer en los pacientes con EPOC la calidad de vida autopercibida, el apoyo social con que cuentan y su dinámica familiar.Diseño: descriptivo transversal.Material y métodos: selección mediante muestreo consecutivo de 278 pacientes diagnosticados de EPOC. Mediante entrevista personal se recogió : perfil sociodemográfico, hábito tabáquico y antecedentes clínicos (comorbilidad), salud autopercibida (perfil de salud de Nottingham, NHP, y Cuestionario Respiratorio St George, SGRQ), apoyo social (Escala de Duke-Unc) y apoyo familiar (test de AP GAR familiar). Estadística descriptiva.Resultados: variables sociodemográficas: varones (88 por ciento), de 66,9ñ8,9 años, casados (87 por ciento), analfabetos (46,7 por ciento), jubilados (77 por ciento). Fumadores (76 por ciento) de 53,2 paquetes/año. Comorbilidad: 76 por ciento pacientes. Los principales resultados de salud autopercibida fueron (medias e IC 95 por ciento): perfil de Salud de Nottingham (0-100): subescalas de energía 40 (35,6-44,4), dolor 35,9 (32,3-39,5), emotividad 32,5 (29,4-38,6), sueño 41,9 (37,8-45,9), so cial 15,3 (12,7-17,9), movilidad 36,7 (33,9-39,5) y total 33,4 (30,8-36). Cuestionario de St. George (0-100): subescalas de impacto 38,01 (35,0840,18), actividad 53,8 (50,2-57,4), síntoma 37,7 (35,2-40,3) y total 40,9 (38,6-43,2). Apoyo social Conclusiones: la calidad de vida de los pacientes con EPOC resultó estar bastante alterada fundamentalmente en las dimensiones de sueño, energía y movilidad del NHP y en la subescala que valora la limitación de la actividad a causa de la disnea del SGRQ. Algo más de la mitad de los pacientes referían buen apoyo social, siendo mayor el afectivo que el confidencial. Consideramos importante el porcentaje de disfunción familiar (20,3 por ciento) (AU)

Fluorescence-labelled DNA probes to detect complementary sequences in homogeneous media.

Sensitive, safe and easy-to-use probes for the detection of nucleic acids are urgently called for. To this end we are in the process of developing a fluorescence-based technique to work in homogeneous assay media. We have examined pyrene and fluorescein as fluorescent labels for natural DNA probes. A fraction of the cytosine residues of a single-stranded cDNA was randomly labelled with either pyrene or fluorescein using the bisulfite-catalyzed diamine reaction. Both fluorophores showed fluorescence quenching when the labelled probe was hybridized with its complementary strand and we describe the changes in steady-state fluorescence intensity that occurred upon hybridization. Our results demonstrate that pyrene quenching is more efficient than fluorescein quenching and thus pyrene-labelled probes are more sensitive for detecting and quantifying DNA from natural sources.

Evolution of pyruvate carboxylase and other biotin containing enzymes in developing rat liver and kidney.

The evolution of pyruvate carboxylase has been studied in rat liver and kidney during perinatal development. The pyruvate carboxylase activity, amount of enzyme and mRNA levels have been assayed from 2 days before delivery to weaning. In liver, there is a peak of activity and amount of enzyme 24 h before delivery and 2 peaks, at 12 h and 6 days, after parturition. The transcription of the enzyme gene followed a similar pattern, with mRNA peaks preceding those of activity and amount of enzyme. However, in kidney, pyruvate carboxylase activity, amount and mRNA remain low until weaning. These results confirm the limited role of renal gluconeogenesis during the perinatal development. Since all carboxylases contain biotin as prosthetic group, the biotinylation of pyruvate carboxylase during the perinatal period was investigated by western-blot using streptavidin-biotin peroxidase. In the mitochondrial samples from liver and kidney, all the pyruvate carboxylase detected was fully biotinylated, indicating an early development of the holocarboxylase synthetase activity in the perinatal period. This Western-blot technique also allowed us the detection of other biotin-enzymes based on their molecular weight. In liver, during the perinatal development propionyl-coA and 3-methyl-crotonyl-coA carboxylases followed a pattern of induction similar to pyruvate carboxylase. In kidney, the expression of mitochondrial carboxylases was lower compared to liver and propionyl-coA carboxylase was not detected during the studied period.

Increased diaphragm expression of GLUT4 in control and streptozotocin-diabetic rats by fish oil-supplemented diets.

Dietary fat intake influences plasma glucose concentration through modifying glucose uptake and utilization by adipose and skeletal muscle tissues. In this paper, we studied the effects of a low-fat diet on diaphragm GLUT4 expression and fatty acid composition in control and streptozotocin-induced diabetic rats. Control as well as diabetic rats were divided into three different dietary groups each. Either 5% olive oil, 5% sunflower oil, or 5% fish oil was the only fat supplied by the diet. Feeding these low-fat diets for 5 wk induced major changes in fatty acid composition, both in control and in diabetic rats. Arachidonic acid was higher in diabetic olive and sunflower oil-fed rats with respect to fish oil-fed, opposite to docosahexaenoic acid which was higher in diabetic fish oil-fed rats with respect to the other two groups. Animals receiving a fish oil diet had the lowest plasma glucose concentration. GLUT4 expression in diaphragm, as indicated by GLUT4 protein and mRNA, is modulated both by diabetes and by diet fatty acid composition. Diabetes induced a decrease in expression in all dietary groups. Plasma glucose levels correlated well with the increased amount of GLUT4 protein and mRNA found in fish oil-fed groups. Results are discussed in terms of the influence that arachidonic and n-3 polyunsaturated fatty acids may exert on the transcriptional and translational control of the GLUT4 gene.

Sequencing of two alternatively spliced mRNAs corresponding to the extracellular domain of the rat receptor for advanced glycosylation end products (RAGE).

The receptor for advanced glycosylation end products (RAGE) is an integral membrane protein responsible for the recognition and internalization of those extensively modified proteins. The receptor has an extracellular domain that binds to the advanced glycosylation end products. By reverse-transcription and polymerase chain reaction amplification, we have identified in rat liver and kidney two amplified products that correspond to cDNA coding for a part of the extracellular domain of the receptor. Sequencing of these products showed that these amplified molecules were similar except for a 27-bp fragment that was absent in the smaller product. This spliced region is located close to the transmembrane region of the receptor. We have confirmed the possibility of the alternative splicing in the generation of these mRNA isoforms by cloning a fragment of the rat gene for RAGE. This fragment has a distribution of introns and exons fully compatible with the proposed alternative splicing.

Effects of starvation, diabetes and carbon tetrachloride intoxication on rat kidney cortex and liver pyruvate carboxylase levels.

Pyruvate carboxylase (PC) has been quantified in rat liver and kidney cortex under experimental conditions that modify the gluconeogenic response in both organs: fasting, carbon tetrachloride-induced liver degeneration and alloxan-induced diabetes. Enzymatic activity has been assayed by a 14CO2-fixation method. The amount of enzyme has been determined by competitive ELISA using antibodies raised against the purified rat kidney cortex enzyme. Purified fractions of rat-liver and rat-kidney cortex PC have been used as standards. Fasting and carbon tetrachloride administration induced a significant increase (25% to 30%) in the amount of enzyme in liver and kidney cortex. Alloxan-induced diabetes produced a nearly two-fold increase in the hepatic levels of enzyme without a significant modification in the content of the renal enzyme. These results are discussed on the basis of the different metabolic implications of both organs during the physiological or toxic treatments.

Mitochondrial pyruvate metabolism in liver and kidney during acidosis.

Pyruvate transport and carboxylation have been determined in mitochondria from liver and kidney cortex isolated from Wistar rats with acidosis produced by three different treatments: fasting, exercise and ingestion of ammonium chloride. Fasting for 48 h or swimming for 2 h resulted in an increased rate of CO2 fixation by mitochondria from both organs incubated with pyruvate. This increase was accompanied by a rise in the rate of pyruvate transport in all cases except in mitochondria derived from the kidney of the fasted animals. Acute acidosis produced by the ingestion of ammonium chloride resulted in increases in pyruvate transport and carboxylation in kidney mitochondria, but a drop in pyruvate carboxylation was observed in mitochondria from the liver. The results are discussed in terms of the differential regulation of the mitochondria steps for gluconeogenesis from three carbon precursors in liver and kidney, taking into consideration the hormonal status of the animals and the prevailing available substrates in each condition.

cAMP-independent synergistic effects of insulin and dexamethasone on fructose 2,6-bisphosphate metabolism in H4IIE cells.

Hormonal regulation of fructose 2,6-bisphosphate (Fru-2,6-P2) content was studied in H4IIE cells. These cells were found to be very sensitive to physiological concentrations of insulin. Addition of either insulin or dexamethasone alone increased Fru-2,6-P2 in a time- and dose-dependent manner, and the maximal effect of the hormones was seen at 1 h. Neither hormone had any measurable effect on cAMP levels. The effect of addition of both insulin and dexamethasone on Fru-2,6-P2 was synergistic. Insulin, but not dexamethasone, rapidly increased 6-phosphofructo-2-kinase (6PF-2-K) activity by causing dephosphorylation of the enzyme as judged by a decrease in the Km for fructose-6-phosphate. Addition of both hormones also resulted in a synergistic 10-fold increase in enzyme protein as measured by kinase activity and phosphoenzyme formation. Dexamethasone increased liver 6PF-2-K/Fru-2,6-P2 mRNA abundance by 10- to 12-fold as measured by a ribonuclease protection assay, and insulin increased it by only 4-fold. Effects were observed as early as 1 h after hormone addition, but addition of both hormones together showed no synergy. We conclude that the synergistic effects of insulin and dexamethasone on Fru-2,6-P2 content are mediated by a combination of stimulation of expression of the bifunctional enzyme gene by both hormones and insulin-induced modulation of the activation state of the bifunctional enzyme, both of which are mediated by cAMP-independent mechanisms.

Regulation of rat-kidney cortex fructose-1,6-bisphosphatase activity. I. Effects of fructose-2,6-bisphosphate and divalent cations.

1. The native rat-kidney cortex Fructose-1,6-BPase is differentially regulated by Mg2+ and Mn2+. 2. Mg2+ binding to the enzyme is hyperbolic and large concentrations of the cation are non-inhibitory. 3. Mn2+ produces a 10-fold rise in Vmax higher than Mg2+. [Mn2+]0.5 is much larger than [Mg2+]0.5. At elevated [Mn2+] inhibition is observed. 4. Mg2+ and Mn2+ produce antagonistic effects on the inhibition of the enzyme by high substrate. 5. Fru-2,6-P2 inhibits the enzyme by rising the S0.5 and favouring a sigmoidal kinetics. 6. The inhibition by Fru-2,6-P2 is released by Mg2+ and more powerfully by Mn2+ increasing the I0.5.