Distribución de especies y susceptibilidad antimicrobiana en cepas de Enterococcus de origen clínico / Distribution of species and antimicrobial susceptibility in Enterococcus strains of clinical origin

A fin de establecer la frecuencia de aislamiento de las diferentes especies de enterococos, su distribución de acuerdo al tipo de muestra y servicio de atención al paciente y determinar la resistencia antimicrobiana, se analizaron 1.624 cepas provenientes de cultivos bacteriológicos de pacientes atendidos en el Centro de Referencia Bacteriológica del Servicio Autónomo Hospital Universitario de Maracaibo, durante el período Enero 2010 - Diciembre 2015. Las especies más frecuentes fueron E. faecalis (52,46%) y E. faecium (41,38%). El mayor número de cepas se obtuvo a partir de muestras de piel y tejidos blandos (54,92%), orina (23,15%) y sangre (17,27%). Los servicios con mayor frecuencia de aislamiento fueron: hospitalización de adultos (47,71%) y hospitalización pediátrica (16,38%). No se encontró asociación estadísticamente significativa entre la especie de enterococos y el tipo de muestra o el servicio de atención al paciente (p>0,05). Se detectó más resistencia en E. faecium que en E. faecalis. Los enterococos están adquiriendo cada vez mayor resistencia antimicrobiana y, por lo tanto, se hace necesario mantener una vigilancia permanente sobre ellos, realizar su adecuada identificación y detectar oportunamente la resistencia, con el fin de aplicar medidas preventivas adecuadas antes de que estos microorganismos causen un mayor impacto intrahospitalario.

In order to establish the frequency of isolation of the different species of enterococci, their distribution according to the type of sample and patient care service and determine the antimicrobial resistance, 1,624 strains obtained from bacteriological cultures of patients attended in the Bacteriological Reference Center at the Autonomous Service University Hospital of Maracaibo, during the period January 2010 - December 2015, were analyzed. The most frequent species were E. faecalis (52.46%) and E. faecium (41.38%). The greatest number of strains was obtained from skin and soft tissues samples (54.92%), urine (23.15%) and blood (17.27%). Services with increased frequency of isolation were: hospitalization of adults (47.71%) and pediatric hospitalization (16.38%). It did not find statistically significant association between the specie of enterococci and sample type, or patient care service (p > 0.05). It was detected more resistance in E. faecium than in E. faecalis. The enterococci are acquiring ever greater antimicrobial resistance, and therefore, it is necessary to maintain permanent vigilance over them, perform their proper identification and timely detect resistance, in order to apply preventive measures before these microorganisms cause a greater intrahospital impact.

Extrusion decreases the negative effects of kidney bean on enzyme and transport activities of the rat small intestine.

The objective of the present study was to evaluate the influence of raw and extruded kidney bean (Phaseolus vulgaris L. var. Pinto) consumption on the gut physiology of young growing rats. The intestinal enzyme activity (sucrase, maltase, Na(+) /K(+) ATPase, aminopeptidase N, dipeptidylpeptidase IV, alkaline phosphatase) and the uptake of sugar (d-galactose) and amino acids (l-leucine) were measured in brush border membrane vesicles. Five groups of growing male Wistar rats were fed ad libitum for 15 days on five different 10% protein diets: one containing casein as the main source of protein (Control, C), and four containing raw (RKB1, RKB6) or extruded kidney bean (EKB1, EKB6) at 1% and 6% of total protein content respectively. Extrusion treatment significantly reduced the content of bioactive factors (phytates, tannins) and abolished lectins, trypsin, chymotrypsin, and α-amylase inhibitory activities. Rats fed raw beans (especially RKB6) showed lower growth rate and food intake as compared to those fed extruded legumes, probably due to the high levels of lectins and other anti-nutritive factors in the raw beans. Gut enzymatic activities and uptake of d-galactose and l-leucine were lower in RKB6 and RKB1-fed animals, although they significantly improved in the groups fed extruded beans. Enzymatic activity and uptake in EKB1 were similar to those of casein-fed rats, whereas the uptake and growth rate of EKB6 were different to the control. This is attributable to the higher non-thermolabile biofactor content in the EKB6 diet, especially phytates and tannins, than in EKB1. This article shows the dose-dependent toxicological effects of bioactive factors contained in kidney beans on gut function. The extrusion process reduced their adverse impact on gut physiology and growth rate.

The impact of adherence and disease control on resource use and charges in patients with mild asthma managed on inhaled corticosteroid agents.

OBJECTIVE: Inadequate asthma control may affect asthma resource use and treatment charges, consequently contributing to the growing economic burden of asthma. The study objective was to determine the impact of medication adherence and asthma control on resource use and charges in mild asthmatic patients treated with inhaled corticosteroids (ICSs). RESEARCH DESIGN AND METHODS: A claims database was analyzed retrospectively from October 2001-December 2007 to identify mild asthmatic patients aged 12-65 years who began ICS treatment. Demographics, drug utilization, and resource use for each patient were identified for the 365-day period before and after the index date (pre-index and post-index periods, respectively). Patients were designated as having high control high adherence (HCHA) or low control low adherence (LCLA) based on post-index exacerbations and the percentage of days covered; not all patients who qualified for study inclusion met adherence designation requirements. Differences between the HCHA and LCLA cohorts in resource use (eg, asthma treatment days) and asthma-related treatment charges were assessed. RESULTS: Compared with the HCHA cohort (n = 483), the LCLA cohort (n = 258) had more asthma treatment days (2.9 vs 3.9, respectively; P < 0.0001) and higher overall asthma treatment charges ($2655 vs $3345, respectively; P < 0.0001) in the post-index period. An adjusted odds ratio suggested that patients receiving mometasone furoate (MF) were approximately 5 times more likely to belong to the HCHA cohort than patients receiving any other ICS (P < 0.0001). CONCLUSIONS: Better asthma control and adherence to prescribed ICSs are associated with lower asthma-related resource use and charges. Mild asthmatic patients receiving MF were more likely to be in the HCHA cohort than patients receiving other ICSs, perhaps due to the once-daily dosing of MF. Current NAEPP guidelines recommend low-dose ICS monotherapy for mild persistent asthma; thus, it is critical to optimize mild persistent asthma control and limit unnecessary resource use and charges.

Los cuidados paliativos y el tratamiento del dolor en la solidaridad internacional / No disponible

Los cuidados paliativos (CP) y el tratamiento del dolor (TD) son elementos esenciales para mejorar o mantener la calidad de vida de muchos enfermos afectados por procesos incurables, crónicos o terminales. Su necesidad se acentúa en países con bajos y medianos recursos donde la incidencia del cáncer y de otras enfermedades como el sida va en aumento con una alta proporción de pacientes diagnosticados en fase avanzada y con un muy difícil acceso a un CP o TD adecuado a pesar de que son la única alternativa realista y humana al abandono que sufren la gran mayoría de estos enfermos. Además el perfil epidemiológico de muchos países del sur está cambiando con un aumento de enfermedades crónicas y el acceso a niveles más altos de cobertura de antirretrovirales. Para modificar esta situación, los CP y el TD deben ser incorporados por los gobiernos a sus sistemas de salud. Es también necesario que estos sean considerados una forma más de cooperación internacional. Se revisan diversos aspectos para una mayor colaboración sanitaria española en este campo con Latinoamérica y África y se sugieren vías para hacerlo a distintos niveles institucionales y asociativos (AU)

Palliative Care (PC) and pain management (PM) are key elements for improved or sustained quality of life in many patients suffering from incurable, chronic, or end-stage conditions. Their need is more critical in low- and mid-resource countries where the incidence of cancer and other diseases such as AIDS is on the rise, with a high percentage of patients diagnosed in advanced stages, and with a difficult access to adequate PC and PM despite they are the only realistic, humane option to relieve the high levels of neglect seen in a great majority of these individuals. Also, the epidemiological profile of many Southern countries is changing, with an increase in chronic conditions and access to higher antiretroviral coverage levels. To modify this situation PC and PM must be incorporated by governments into their healthcare systems. It is also necessary that PC and PM be considered an additional means of international cooperation. The various aspects required for greater Spanish cooperation with LatinAmerica and Africa in this field are reviewed, and ways towards this end are suggested at various institutional and associational levels (AU)

Cuidados paliativos y tratamiento del dolor en la solidaridad internacional / Palliative care and pain treatment: international solidarity

Los cuidados paliativos (CP) y el tratamiento del dolor (TD) son elementos esenciales para mejorar o mantener la calidad de vida de muchos enfermos afectados por procesos incurables, crónicos o terminales. Su necesidad se acentúa en países con bajos y medianos recursos donde la incidencia del cáncer y de otras enfermedades como el sida va en aumento, con una alta proporción de pacientes diagnosticados en fase avanzada y con un muy difícil acceso a unos CP o TD adecuados, a pesar de que son la única alternativa realista y humana al abandono que sufren la gran mayoría de estos enfermos. Además el perfil epidemiológico de muchos países del sur está cambiando con un aumento de enfermedades crónicas y el acceso a niveles más altos de cobertura de antirretrovirales. Para modificar esta situación, los gobiernos deben incorporar los CP y el TD en sus sistemas de salud. También es necesario que éstos se consideren una forma más de cooperación internacional. Se revisan diversos aspectos para una mayor colaboración sanitaria española en este campo con Latinoamérica y África, y se sugieren vías para hacerlo a distintos niveles institucionales y asociativos (AU)

Palliative care and pain treatment are essential to improve or maintain quality of life in many patients with incurable, chronic or terminal diseases. The need for palliative careis more pressing in countries with scarce or medium resources and where the incidence of cancer and other diseases such as AIDS is increasing. In these countries, a high proportion of patients are diagnosed in the advanced stage of the disease and access to appropriate palliative care and pain treatment is difficult, even though these options are the only realistic and human alternatives to the abandonment experienced by most of these patients. Moreover, the epidemiological profile of many southern countries is changing, with an increase of chronic diseases and access to higher levels of antiretroviral coverage. To modify this situation, governments should incorporate palliative care and pain treatment in their health systems and these options should also be seen as one more form of international cooperation. The present article reviews several factors required for greater healthcare collaboration between Spain and Latin America and Africa and suggests ways to achieve this collaboration through distinct institutions and associations (AU)

Envejecimiento, deterioro cognitivo y lenguaje: resultados del Estudio Longitudinal Donosita / Aging, cognitive impairment and language: Results from the Donostia Longitudinal Study

El Estudio Longitudinal Donostia ha investigado el efecto de las intervenciones de tipo no farmacológicoen personas mayores sin deterioro cognitivo, condeterioro cognitivo leve y con demencia. El presentetrabajo se deriva de dicho estudio y pretende profundizaren el perfil lingüístico de las personas participantes,así como realizar una primera aproximaciónempírica al efecto de una intervención de tipomulticomponente en variables de tipo lingüístico.Para ello se ha contado con una muestra de 395 sujetosdistribuidos entre los estadios 1 y 4 de la GlobalDeterioration Scale (GDS). Se han realizado tres grupospor cada estadio: uno de ellos siguió una intervenciónde acuerdo a un modelo de deterioro por estadios, elsegundo realizó tareas de estimulación sin ningúnmodelo prefijado y el tercero no recibió ningún tipo deintervención.Los resultados muestran un mejor rendimiento enlos participantes con GDS 1 y 2 respecto a aquellosque presentan deterioro cognitivo. Entre GDS 3 y 4, seproducen diferencias en vocabulario, escritura y fluidezsemántica, pero no en comprensión auditiva,comprensión escrita y fluidez fonológica. Respecto alefecto de la intervención estimulativa, se observa unamejora en las variables que miden procesos léxicofonológicosen aquéllos participantes que no presentandeterioro cognitivo(AU)

Donostia Longitudinal Study has investigated the effect of non-pharmacological interventions inolder adults without cognitive impairment, withmild cognitive impairment and with dementia. Thecurrent work is derived from this study and aimsto go in depth into the linguistic profile of participants,as well as to perform a first empiricalapproximation to the effect of multi-type interventionin linguistic constructs.We have had a sample of 395 subjects dividedbetween stages from 1 to 4 of the Global DeteriorationScale (GDS). There have been threegroups for each stage: one of them followed anintervention established according to a patternof decline by stages; the second performed stimulationtasks without any theoretical backgroundand the third did not receive any kind ofintervention.The results showed a better performance in participantswith GDS 1 and 2 compared to those withcognitive impairment. Between GDS 3 and 4, differenceswere found in vocabulary, writing andsemantic fluency, but not in listening comprehension,reading comprehension and phonologicalfluency. Regarding to the effect of the intervention,an improvement is observed for those variablesthat measure lexical-phonological processesin those participants who do not suffer cognitiveimpairment(AU)

Genes related to iron metabolism and susceptibility to Alzheimer's disease in Basque population.

Alzheimer's disease (AD) is the most common dementing disorder and presents with a progressive and irreversible cognitive decline of gradual onset. To date, several reports have involved iron in AD physiopathology. In this study, we have analysed TFC2 variant and HFE mutations (H63D and C282Y) in 211 AD patients and 167 controls recruited from an area of the Basque Country. Furthermore, we have studied APOE genotype as it is a well-known risk factor for AD. APOE epsilon 4 allele was associated with an increased risk of AD and an earlier age at onset, whereas no association was found between TFC2 or HFE C282Y mutation and disease susceptibility. The frequency of H63D mutation was higher in control population (29.9%) than in AD patients (18%), suggesting a protective role of this allele on AD either due to the presence of the mutation itself or through the effect of other related genes in the ancestral haplotype in which it is included.

Modulación de la fisiología gastrointestinal mediante cepas probióticas de Lactobacillus casei y Bifidobacterium bifidum / Modulation of gastrointestinal physiology through probiotic strains of Lactobacillus casei and Bifidobacterium bifidum

En el contexto de la alimentación y la promoción de la salud se sitúan los productos denominados alimentos funcionales que tienen diversos efectos beneficiosos en el organismo, además de los meramente nutricionales. Dentro de estos alimentos funcionales, entre otros, podemos distinguir entre compuestos probióticos y prebióticos. Los microorganismos más utilizados en alimentos probióticos pertenecen a los géneros Lactobacillus y Bifidobacterium. En el presente trabajo se ha estudiado el efecto de dietas suplementadas con Lactobacillus casei o Bifidobacterium bifidum en el desarrollo animal y en especial sobre la función intestinal, centrada en su actividad immunitaria, digestiva y absortiva de animales en crecimiento. Las cepas bacterianas utilizadas modifican la actividad del intestino delgado de los ratones sanos, afectando significativamente a su actividad enzimática (sacarasa, maltasa y aminopeptidasa) y a la captación de nutrientes (galactosa y glicilsarcosina), así como a la actividad inmune intestinal (mayor número de placas de Peyer). Sin embargo, estos efectos no parecen perturbar el desarrollo de los animales en crecimiento ya que no se aprecian diferencias significativas en su peso corporal ni en sus parámetros sanguíneos. Estos resultados ponen de manifiesto los posibles efectos beneficiosos en la fisiología intestinal y contribuyen al conocimiento de los posibles mecanismos de acción de los probióticos, que se pudieran utilizar en el tratamiento preventivo de diferentes patologías relacionadas con el aparato digestivo

The products called functional foods, which besides being merely nutritional have different beneficial effects on the organism, are situated in the context of diet and health promotion. Amongst these functional foods we can distinguish, amongst others, between probiotic and prebiotic compounds. The microorganisms most widely used in probiotic foods belong to the Lactobacillus and Bifidobacterium types. In this article we have studied the effect of diets supplemented with Lactobacillus casei or Bifidobacterium bifidum on animal development and especially on the intestinal function, centred on their immune, digestive and absorptive activity in growing animals. The bacteria strains used modify the activity of the small intestine of healthy mice, significantly affecting their enzymatic activity (sucrase, maltase and aminopeptidase) and the collection of nutrients (galactose and glycilsarcosine), as well as the intestinal immune activity (higher number of Peyer’s patches). However, these effects do not appear to disturb the development of the growing animals since no significant differences are appreciated in their body weight or in their blood parameters. These results make clear the possible beneficial effects on intestinal physiology and contribute to the understanding of the possible mechanisms of action of the probiotics, which could be employed in the preventive treatment of different pathologies related to the digestive apparatus

Effect of dietary quercetin and sphingomyelin on intestinal nutrient absorption and animal growth.

Research on cancer and other conditions has shown flavonoids and sphingolipids to be food components capable of exerting chemoprotective action. Nevertheless, little is known about their effects on healthy individuals and their potential usefulness as therapeutic agents. The present study examined the possible action of a dietary flavonoid, quercetin, and a sphingolipid, sphingomyelin, as functional foods in healthy animals. In particular, the effect on animal growth of supplementing a conventional diet with one or other of these substances (0.5 % quercetin and 0.05 % sphingomyelin) was considered. Possible action affecting intestinal physiology was also analysed by measuring the uptake of sugar and dipeptide, mediated by the Na(+)-dependent sugar transporter SGLT1 and the dipeptide Na(+)/H(+) exchanger PEPT1 respectively, and the activity of related intestinal enzymes such as sucrase, maltase and aminopeptidase N. Both substances seemed to modify small intestinal activity in healthy mice, altering intestinal enzymatic activity and nutrient uptake. These effects observed in the small intestine did not impair normal development of the animals, as no differences in serum biochemical parameters or in organ and body weights were found. The findings should help in elucidating the mechanisms of action of these food components with a view to their possible use in the prevention of certain pathological conditions.

[Modulation of gastrointestinal physiology through probiotic strains of Lactobacillus casei and Bifidobacterium bifidum]. / Modulación de la fisiología gastrointestinal mediante cepas probióticas de Lactobacillus casei y Bifidobacterium bifidum.

The products called functional foods, which besides being merely nutritional have different beneficial effects on the organism, are situated in the context of diet and health promotion. Amongst these functional foods we can distinguish, amongst others, between probiotic and prebiotic compounds. The micro-organisms most widely used in probiotic foods belong to the Lactobacillus and Bifidobacterium types. In this article we have studied the effect of diets supplemented with Lactobacillus casei or Bifidobacterium bifidum on animal development and especially on the intestinal function, centred on their immune, digestive and absorptive activity in growing animals. The bacteria strains used modify the activity of the small intestine of healthy mice, significantly affecting their enzymatic activity (sucrase, maltase and aminopeptidase) and the collection of nutrients (galactose and glycilsarcosine), as well as the intestinal immune activity (higher number of Peyer's patches). However, these effects do not appear to disturb the development of the growing animals since no significant differences are appreciated in their body weight or in their blood parameters. These results make clear the possible beneficial effects on intestinal physiology and contribute to the understanding of the possible mechanisms of action of the probiotics, which could be employed in the preventive treatment of different pathologies related to the digestive apparatus.

Ácido fólico (y III) / Folid acid (and III)

No disponible

Acido fólico (II) / Folic Acid (II)

No disponible

Ácido fólico (I) / Folic acid

No disponible

No disponible

Nutritional quality of extruded kidney bean (Phaseolus vulgaris L. var. Pinto) and its effects on growth and skeletal muscle nitrogen fractions in rats.

The influence of extrusion cooking on the protein content, amino acid profile, and concentration of antinutritive compounds (phytic acid, condensed tannins, polyphenols, trypsin, chymotrypsin, alpha-amylase inhibitors, and hemagglutinating activity) in kidney bean seeds (Phaseolus vulgaris L. var. Pinto) was investigated. Growing male rats were fed diets based on casein containing raw or extruded kidney beans with or without methionine supplementation for 8 or 15 d. Rates of growth, food intake, and protein efficiency ratio were measured and the weight of the gastrocnemius muscle and the composition of its nitrogenous fraction was determined. Extrusion cooking reduced (P < 0.01) phytic acid, condensed tannins, and trypsin, chymotrypsin, and (alpha-amylase inhibitory activities. Furthermore, hemagglutinating activity was abolished by extrusion treatment. Protein content was not affected by this thermal treatment. Rats fed raw kidney bean lost BW rapidly and the majority died by 9 d. Pretreatment of the beans by extrusion cooking improved food intake and utilization by the rats and they gained BW. Supplementation of extruded kidney bean with methionine further enhanced (P < 0.01) food conversion efficiency and growth. However, BW gains and muscle composition still differed (P < 0.01) from those of rats fed a high-quality protein.

Liver proteolytic activity in tannic acid-fed birds.

The influence of tannic acid in the rate of growth (BWG), feed intake, protein efficiency ratio, and liver proteolytic activities (cathepsin A and D) were measured in growing male chickens. These birds were fed ad libitum over a 15-d experiment on 20% protein standard diets containing heated soybean (control, C) as the main source of protein. Tannic acid (TA; 25 g/kg diet) was added to all diets, except the control. It has been found that in comparison to control-fed birds, TA-fed birds showed a significant reduction (P < 0.01) in BWG, protein efficiency ratio, and relative weight of liver, together with a significant increase (P < 0.01) in the activities of cathepsin A and D in liver. Addition of TA to the control diet had no significant effect on feed intake. The possible nature of these results is discussed.

Virulent strains of Salmonella enteritidis disrupt the epithelial barrier of Caco-2 and HEp-2 cells.

To confirm the existence in nature of Salmonella enteritidis strains of different degrees of virulence and to elucidate the mechanisms underlying the effects of such strains on the epithelial barrier function, the consequences of infection of Caco-2 cells and HEp-2 cells with 15 S. enteritidis strains in a chicken infection model were examined. The more virulent strains of S. enteritidis, which are biofilm producers in adherence test medium, were able to disrupt HEp-2 and Caco-2 monolayers, as shown by transmonolayer electrical resistance and lactate dehydrogenase activity. In contrast, the low-virulence strains of S. enteritidis, which do not produce biofilms in adherence test medium, had no effect on the same cells. An avirulent rough mutant of Salmonella minnesota exhibited a pattern of behaviour similar to that of the low virulence strains of S. enteritidis, whilst a clinical Salmonella typhi strain caused rapid injury to the monolayers. The effect of supernatants of Salmonella cultures in adherence test medium on the integrity of Caco-2 cell monolayers indicated that the high-virulence S. enteritidis strains, but not the low-virulence strains, release a soluble factor when incubated under optimum biofilm-forming conditions, which enables the disruption of the integrity of Caco-2 monolayers.

Altered intestinal transport of amino acids in cirrhotic rats: the effect of insulin-like growth factor-I.

The intestine is an important target organ for insulin-like growth factor-I (IGF-I), an anabolic hormone synthesized in the liver upon growth hormone (GH) stimulation. Levels of IGF-I are reduced in cirrhosis, and altered GH/IGF-I axis may contribute to malnutrition in cirrhotic patients. Our aim was to study Na(+)-dependent jejunal transport of amino acids (L-leucine, L-proline, L-glutamic acid, and L-cysteine) in cirrhotic rats and to analyze the effect of IGF-I on this function. IGF-I or saline was administered for 2 wk to rats with CCl(4)-induced cirrhosis and saline was administered to healthy control rats. Transport of amino acids was assessed in brush-border membrane vesicles (BBMV) using (14)C- or (35)S-labeled amino acids, and the kinetic constants V(max) and K(t) were determined. Na(+)-independent uptake of L-leucine, L-proline, L-glutamic acid, and L-cysteine by BBMV was similar in all groups. Na(+)-dependent uptake of all four amino acids was significantly diminished in cirrhotic rats compared with both controls and IGF-I-treated cirrhotic rats. The latter two groups exhibited similar V(max) and K(t), whereas untreated cirrhotic rats had reduced V(max) and increased K(t) compared with normal controls and IGF-I-treated cirrhotic animals. In conclusion, the transport of all four tested amino acids by BBMV is impaired in cirrhotic rats, and low doses of IGF-I can correct this defect.

Hepatitis A in Latin America: a changing epidemiologic pattern.

In a multicenter study, hepatitis A virus (HAV) seroprevalence was surveyed in six countries in Latin America in which in 12,000 subjects were stratified for age. The highest rates of seroprevalence were recorded in the Dominican Republic (89.0%) and Mexico (81.0%), with lower rates in Brazil (64.7%), Chile (58.1%), Venezuela (55.7%), and Argentina (55.0%). The seroprevalence of HAV in children between 1 and 5 years of age was less than 50%, except in the Dominican Republic. In the 5-10-year-old age group, seroprevalence rates have also decreased compared with previous reports. This suggests that the epidemiology is shifting from high to intermediate endemicity, with the population susceptible to HAV infection shifting from children to adolescents and adults. Furthermore, data from Brazil, Argentina, and Mexico show that HAV seroprevalence is significantly lower in people living in medium and high socioeconomic conditions. This study suggests the need for appropriate vaccination programs to be implemented targeting children, adolescents, and adults, particularly in higher socioeconomic groups.

Galactose transport inhibition by cytochalasin E in rat intestine in vitro.

Cytochalasins are cytoskeleton disrupters, and cytochalasin E has been reported to increase intestinal paracellular permeability. In this study, the cytochalasin E effect on galactose transport has been investigated. Ussing-type chamber experiments show an inhibitory effect of 20 microM cytochalasin E on unidirectional mucosal to serosal flux of galactose. On the contrary, the opposite unidirectional flux is not modified by the inhibitor. Results using intestinal everted sacs and rings confirm that galactose uptake by the tissue is diminished by cytochalasin E. The effect appears already after 5 min incubation, depends on cytochalasin E concentration, and does not occur in the absence of Na+. The inhibition is accompanied by an increase in the apparent K(m) of the active sugar transport (11.5 vs.15.8 mM) without significant change in the VmaX (10.6 vs. 9.1 micromol x g(-1) wet weight x 5 min(-1)). Cytochalasin E does not modify either galactose uptake by brush border membrane vesicles or Na(+)-K(+) ATPase activity in the enterocytes, indicating that the inhibitory effect on the Na(+)-dependent sugar transport cannot be explained as a direct effect on SGLT1 activity or as an indirect effect through the Na(+)-K(+) ATPase. Thus, our results suggest that cytochalasin E decreases SGLTI activity indirectly through cytoskeleton disruption.

Effect of insulin-like growth factor I on in vivo intestinal absorption of D-galactose in cirrhotic rats.

Insulin-like growth factor I (IGF-I) bioavailability is reduced in liver cirrhosis, a condition frequently associated with malnutrition. We have analyzed in vivo absorption of D-galactose by jejunal loops in rats with CCl4-induced liver cirrhosis and the influence of IGF-I on intestinal sugar transport in this disease. Two different study protocols were followed. In protocol 1, healthy control rats or cirrhotic rats received saline or IGF-I (2 micrograms . 100 g body wt-1. day-1) for 2 wk. In protocol 2, control and cirrhotic rats received saline or IGF-I as a bolus injection of 1 microgram/100 g body wt followed by continuous infusion of the same dose for 100 min. In vivo D-galactose absorption was reduced in cirrhotic rats compared with healthy controls. IGF-I, as both a chronic (protocol 1) and acute treatment (protocol 2), was able to improve sugar transport in cirrhotic rats but had no effect on sugar absorption in healthy rats. A significant elongation of enterocyte microvilli was observed in cirrhotic animals; this alteration was totally or partially corrected by chronic or acute IGF-I administration. Our results show that in vivo jejunal sugar transport and microvilli structure are altered in liver cirrhosis and that IGF-I, among other effects, may correct these changes by modulating cytoskeletal organization in enterocytes.