Resumen:

Comprobada la parasitosis por CAPILLARIA CAUDINFLATA, los autores logran reproducir la enfermedad en pollos mantenidos libres de toda infestación dándoles a ingerir lombrices recogidas en los gallineros de los que procedían las aves originalmente necropsiadas. Demostrando así el papel de Eisenia sp. como hospedador intermediario de aquel nematode.

After the verification of the parasitose caused by CAPILLARIA CAUDINFLATA the authors obtained the reproduction of the disease in chicken free of any infestation giving to the birds to eat worms arising from the poultry yard where were lodged the birds originally necropsied. This way the workers show the paper of Eisenia sp. as intermediary host of that nematodes.

Facultad de Ciencias Veterinarias

Resumen:

Studies on birds have led to the hypothesis that increased intestinal absorption between enterocytes (paracellular) evolved as a compensation for smaller intesti- nal size in fliers, which was perhaps selected to minimize the mass of digesta carried. This hypothesis predicts that bats will also exhibit relatively reduced intestinal size and high paracellular absorption, compared with nonflying mammals. Published studies on three bat species indicate relatively high paracellular absorption. One mechanism for increasing paracellular absorption per cm2 small intestine (SI) is increased number of tight junctions (TJs) across which para- cellular absorption occurs. To our knowledge, we provide the first comparative analysis of enterocyte size and number in flying and nonflying mammals. Intestines of insectivorous bats Tadarida brasiliensis were compared with Mus muscu- lus using hematoxylin and eosin staining method. Bats had shorter and narrower SIs than mice, and after correction for body size difference by normalizing to mass3/4, the bats had 40% less nominal surface area than the mouse, as predicted. Villous enhancement of surface area was 90% greater in the bat than in the mouse, mainly because of longer villi and a greater density of villi in bat intestines. Bat and mouse were similar in enterocyte diameter. Bats exceeded mice by 54.4% in villous area per cm length SI and by 95% in number of enterocytes per cm2 of the nominal surface area of the SI. Therefore, an increased density of TJs per cm2 SI may be a mechanistic explanation that helps to understand the high paracellular absorption observed in bats compared to nonfly- ing mammals.

Afiliación de los autores: Zhang, Zhi Qiang . Anhui Agricultural University (AAU); China. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina

Afiliación de los autores: Brun, Antonio. Universidad Nacional de San Luis. Facultad de Quimica, Bioquimica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Afiliación de los autores: Price, Edwin R.. University Of Wisconsin; Estados Unidos

Afiliación de los autores: Cruz Neto, Ariovaldo P.. Universidade Estadual Paulista Julio de Mesquita Filho; Brasil

Afiliación de los autores: Karasov, William H.. University Of Wisconsin; Estados Unidos

Afiliación de los autores: Caviedes Vidal, Enrique Juan Raul. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; Argentina. University Of Wisconsin; Estados Unidos. Universidad Nacional de San Luis; Argentina

Resumen:

Inflammatory bowel diseases (IBD) are chronic and relapsing inflammatory conditions of the gastrointestinal tract including Crohn’s disease (CD) and ulcerative colitis (UC). Galectins, defined by shared consensus amino acid sequence and affinity for b-galactosides, are critical modulators of the inflammatory response. However, the relevance of the galectin network in the pathogenesis of human IBD has not yet been explored. Here, we analyzed the expression of relevant members of the galectin family in intestinal biopsies, and identified their contribution as novel mucosal markers in IBD. Colonic biopsies were obtained from 59 IBD patients (22 CD and 37 UC), 9 patients with gut rejection after transplantation, 8 adult celiac patients, and 32 non-IBD donors. Galectin mRNA expression was analyzed by RT-PCR and qPCR using specific primers for individual galectins. A linear discriminant analysis (LDA) was used to analyze galectin expression in individual intestinal samples. Expression of common mucosalassociated galectins (Gal-1, 23, 24, 29) is dysregulated in inflamed tissues of IBD patients compared with non-inflamed IBD or control samples. LDA discriminated between different inflammation grades in active IBD and showed that remission IBD samples were clusterized with control samples. Galectin profiling could not distinguish CD and UC. Furthermore, inflamed IBD was discriminated from inflamed tissue of rejected gut in transplanted patients and duodenum of celiac patients, which could not be distinguished from control duodenum samples. The integrative analysis of galectins discriminated IBD from other intestinal inflammatory conditions and could be used as potential mucosal biomarker.

Afiliación de los autores: Papa Gobbi, Rodrigo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; Argentina

Afiliación de los autores: de Francesco, Pablo Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; Argentina

Afiliación de los autores: Bondar, Constanza María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; Argentina

Afiliación de los autores: Muglia, Cecilia Isabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; Argentina

Afiliación de los autores: Chirdo, Fernando Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; Argentina

Afiliación de los autores: Rumbo, Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; Argentina

Afiliación de los autores: Rocca, Martín. Gobierno de la Ciudad de Buenos Aires. Hospital de Gastroenterología "Dr. Carlos B. Udaondo"; Argentina

Afiliación de los autores: Toscano, Marta Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina

Afiliación de los autores: Sambuelli, Alicia. Gobierno de la Ciudad de Buenos Aires. Hospital de Gastroenterología "Dr. Carlos B. Udaondo"; Argentina

Afiliación de los autores: Rabinovich, Gabriel Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina

Afiliación de los autores: Docena, Guillermo H.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; Argentina

Resumen:

Aims: To evaluate the effect of oral administration of Lactobacillus fermentum CRL1446 on the intestinal feruloyl esterase (FE) activity and oxidative status of mice. Methods and Results: Adult Swiss albino mice received Lact. fermentum CRL1446 at the doses 107 and 109 cells per day per mouse for 2, 5, 7 and 10 days. Intestinal FE activity, intestinal microbiota counts, plasmatic thiobarbituric acid-reactive substances (TBARS) percentage and glutathione reductase (GR) activity were determined. Mice that received Lact. fermentum CRL1446 at the dose 107 cells per day for 7 days showed a twofold increase in total intestinal FE activity, compared to the nontreated group. In large intestine content, FE activity increased up to 6Æ4 times. No major quantitative changes in colonic microbiota were observed in treated animals. Administration of this strain produced an approx. 30–40% decrease in the basal levels of plasmatic TBARS and an approx. twofold increase in GR activity from day 5 of feeding with both doses. Conclusions: Oral administration of Lact. fermentum CRL1446 to mice increases total intestinal FE activity, decreases the basal percentage of plasmatic lipoperoxides and increases GR activity. Significance and Impact of the Study: Lactobacillus fermentum CRL1446 could be orally administered as a dietary supplement or functional food for increasing the intestinal FE activity to enhance the bioavailability of ferulic acid, thus improving oxidative status.

Afiliación de los autores: Abeijon Mukdsi, Maria Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentina. Universidad del Norte Santo Tomás de Aquino; Argentina

Afiliación de los autores: Gauffin Cano, María Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentina. Universidad del Norte Santo Tomás de Aquino; Argentina

Afiliación de los autores: Gonzalez, Silvia Nelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentina

Afiliación de los autores: Medina, Roxana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentina. Universidad del Norte Santo Tomás de Aquino; Argentina

Resumen:

Giardiasis, caused by the protozoan Giardia intestinalis, is one of the most common intestinal diseases worldwide and constitutes an important problem for the public health systems of various countries. Kefir is a probiotic drink obtained by fermenting milk with ‘kefir grains’, which consist mainly of bacteria and yeasts that coexist in a complex symbiotic association. In this work, we studied the ability of kefir to protect mice from G. intestinalis infection, and characterized the host immune response to this probiotic in the context of the intestinal infection. Six- to 8-week-old C75BL/6 mice were separated into four groups: controls, kefir mice (receiving 1 : 100 dilution of kefir in drinking water for 14 days), Giardia mice (infected orally with 4107 trophozoites of G. intestinalis at day 7) and Giardia–kefir mice (kefir-treated G. intestinalis-infected mice), and killed at 2 or 7 days post-infection. Kefir administration was able to significantly reduce the intensity of Giardia infection at 7 days post-infection. An increase in the percentage of CD4+ T cells at 2 days post-infection was observed in the Peyer’s patches (PP) of mice belonging to the Giardia group compared with the control and kefir groups, while the percentage of CD4+ T cells in PP in the Giardia–kefir group was similar to that of controls. At 2 days post-infection, a reduction in the percentage of B220-positive major histocompatibility complex class II medium cells in PP was observed in infected mice compared with the other groups. At 7 days post-infection, Giardiainfected mice showed a reduction in RcFce-positive cells compared with the control group, suggesting a downregulation of the inflammatory response. However, the percentages of RcFcepositive cells did not differ from controls in the kefir and Giardia–kefir groups. An increase in IgApositive cells was observed in the lamina propria of the kefir group compared with controls at 2 days post-infection. Interestingly, the diminished number of IgA-positive cells registered in the Giardia group at 7 days post-infection was restored by kefir feeding, although the increase in IgApositive cells was no longer observed in the kefir group at that time. No significant differences in CXCL10 expression were registered between groups, in concordance with the absence of inflammation in small-intestinal tissue. Interestingly, a slight reduction in CCL20 expression was observed in the Giardia group, suggesting that G. intestinalis might downregulate its expression as a way of evading the inflammatory immune response. On the other hand, a trend towards an increase in TNF-a expression was observed in the kefir group, while the Giardia–kefir group showed a significant increase in TNF-a expression. Moreover, kefir-receiving mice (kefir and Giardia–kefir groups) showed an increase in the expression of IFN-c, the most relevant Th1 cytokine, at 2 days post-infection. Our results demonstrate that feeding mice with kefir reduces G. intestinalis infection and promotes the activation of different mechanisms of humoral and cellular immunity that are downregulated by parasitic infection, thus contributing to protection.

Afiliación de los autores: Correa, Mariana. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Cátedra de Microbiología General; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones en Criotecnología de Alimentos (i); Argentina

Afiliación de los autores: Golowczyc, Marina Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones En Criotecnología de Alimentos (i); Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas; Argentina

Afiliación de los autores: de Antoni, Graciela L.. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Cátedra de Microbiología General; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones en Criotecnología de Alimentos (i); Argentina

Afiliación de los autores: Perez, Pablo Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones En Criotecnología de Alimentos (i); Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas; Argentina

Afiliación de los autores: Humen, Martin Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigaciones En Criotecnología de Alimentos (i); Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Exactas; Argentina

Afiliación de los autores: Serradell, Maria de Los Angeles. Universidad Nacional de la Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Cátedra de Microbiología General; Argentina

Resumen:

Background: Previously, a bovine intestinal epithelial cell line (BIE cells) was successfully established. This work hypothesized that BIE cells are useful in vitro model system for the study of interactions of microbial- or pathogenassociated molecular patterns (MAMPs or PAMPs) with bovine intestinal epithelial cells and for the selection of immunoregulatory lactic acid bacteria (LAB). Results: All toll-like receptor (TLR) genes were expressed in BIE cells, being TLR4 one of the most strongly expressed. We demonstrated that heat-stable PAMPs of enterotoxigenic Escherichia coli (ETEC) significantly enhanced the production of IL-6, IL-8, IL-1! and MCP-1 in BIE cells by activating both NF-"B and MAPK pathways. We evaluated the capacity of several lactobacilli strains to modulate heat-stable ETEC PAMPs-mediated inflammatory response in BIE cells. Among these strains evaluated, Lactobacillus casei OLL2768 attenuated heat-stable ETEC PAMPs-induced pro-inflammatory response by inhibiting NF-"B and p38 signaling pathways in BIE cells. Moreover, L. casei OLL2768 negatively regulated TLR4 signaling in BIE cells by up-regulating Toll interacting protein (Tollip) and B-cell lymphoma 3-encoded protein (Bcl-3). Conclusions: BIE cells are suitable for the selection of immunoregulatory LAB and for studying the mechanisms involved in the protective activity of immunobiotics against pathogen-induced inflammatory damage. In addition, we showed that L. casei OLL2768 functionally modulate the bovine intestinal epithelium by attenuating heat-stable ETEC PAMPs-induced inflammation. Therefore L. casei OLL2768 is a good candidate for in vivo studying the protective effect of LAB against intestinal inflammatory damage induced by ETEC infection or heat-stable ETEC PAMPs challenge in the bovine host.

Afiliación de los autores: Takanashi, Naoya. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;

Afiliación de los autores: Tomosada, Yohsuke. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;

Afiliación de los autores: Villena, Julio Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Tucuman. Centro de Referencia Para Lactobacilos (i); Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;

Afiliación de los autores: Murata, Kozue. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;

Afiliación de los autores: Takahashi, Takuya. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;

Afiliación de los autores: Chiba, Eriko. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;

Afiliación de los autores: Tohno, Masanori. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan; National Agriculture and Food Research Organization. National Institute of Livestock and Grassland Science; Japan.;

Afiliación de los autores: Tomoyuki Shimazu. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan; Laboratory of Animal Breading and Genetics. Graduate School of Agricultural Science; Japan.;

Afiliación de los autores: Aso, Hisashi. Cell Biology Laboratory, Graduate School of Agricultural Science. Tohoku University; Japan.;

Afiliación de los autores: Suda, Yoshihito. Department of Food, Agriculture and Environment. Miyagi University; Japan.;

Afiliación de los autores: Ikegami, Shuji. Division of Research and Development. Food Science Institut. Meiji Dairies CoOdawara; Japan;

Afiliación de los autores: Itoh, Hiroyuki. Division of Research and Development. Food Science Institut. Meiji Dairies CoOdawara; Japan;

Afiliación de los autores: Kawai, Yasushi. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;

Afiliación de los autores: Tadao Saito. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;

Afiliación de los autores: Alvarez, Gladis Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina;

Afiliación de los autores: Kitazawa, Haruki. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;

Resumen:

Un conjunto de ensayos in vitro simples (identificación por PCR específicos, diversidad genética, crecimiento y viabilidad en la leche, resistencia a sales y compuestos de sabor, interacciones bacterianas, tolerancia al jugo gástrico simulado y a la bilis, deconjugacion de sales biliares, hidrofobicidad y actividades betagalactosidasa y antibacteriana), que puede llevarse a cabo en cualquier laboratorio de Microbiología, principalmente en los países en desarrollo donde a menudo hay acceso limitado a técnicas sofisticadas, nos permitió identificar, entre diecinueve aislamientos humanos intestinales, un potencial candidato para nuevos alimentos lácteos probióticos para el mercado local. Lactobacillus gasseri LgF37/1 desarrolla bien en los medios de cultivo utilizados para la enumeración de bacterias probióticas en productos lácteos argentinos. Esta cepa también mostró elevada tolerancia a los desafíos tecnológicos evaluados, resistencia de sales biliares, la capacidad de producir metabolitos tipo bacteriocina como para inhibir las bacterias patógenas, deconjugar las sales biliares y alta hidrofobicidad. Más investigación in vivo debe llevarse a cabo con esta cepa antes de proclamar propiedades probióticas para ella. Sin embargo, el uso de un conjunto de técnicas sencillas in vitro resultó para ser importante para determinar que las cepas deben someterse a estudios futuros más complejos.

A set of simple in vitro tests (identification by species-specific PCR, genetic diversity, growth and viability in milk, resistance to salts and flavor compounds, bacterial interactions, tolerance to simulated gastric juice and bile, bile salts deconjugation, hydrophobicity and b-galactosidase and antibacterial activities), that can be carried out in almost every laboratory of microbiology, mainly in developing countries where there is often limited access to sophisticated techniques, allowed us to identify, among nineteenth intestinal human isolates, a potential candidate for new probiotic dairy foods for the local market. Lactobacillus gasseri LgF37/1 performed well in the culture media used for the enumeration of probiotic bacteria in argentinian dairy products. This strain showed also high tolerance to the technological challenges assessed, bile salts resistance, the capacity to produce bacteriocin-like metabolites, to inhibit pathogenic bacteria, to deconjugate bile salts and high hydrophobicity. Further in vivo research should be carried out with this strain before claiming probiotic properties for it. However, the use of a set of simple in vitro techniques proved to be important to determine which strains should undergo future and more complex studies.

Resumen:

Accumulation and toxicity of cyanobacterial toxins, particularly microcystin-LR (MCLR) have been extensively studied in fish and aquatic invertebrates. However, MCLR excretion mechanisms, which could reduce this toxin's effects, have received little attention. The Patagonian silverside, Odontesthes hatcheri, is an omnivorous-planktivorous edible fish, which has been shown to digest cyanobacterial cells absorbing MCLR and eliminating the toxin within 48 h without suffering significant toxic effects. We studied the effects of MCLR on glycoconjugate composition and the possible role of multidrug resistance associated proteins (Abcc) in MCLR export from the cells in O. hatcheri intestine. We treated O. hatcheri with 5 μg MCLR g−1 body mass administered with the food. Twenty four hours later, the intestines of treated and control fish were processed for lectin-histochemistry using concanavalin A (ConA), Triticum vulgaris agglutinin (WGA), and Dolichos biflorus agglutinin (DBA). MCLR affected the distribution of glycoconjugates by augmenting the proportion of ConA-positive at the expense of WGA-positive cells. We studied MCLR effects on the transport of the Abcc-like substrates 2,4-dinitrophenyl-S-glutathione (DNP-SG) and calcein in ex vivo intestine preparations (everted and no-everted sacs and strips). In treated preparations, CDNB together with MCLR (113 μg MCLR g−1 intestine, equivalent to 1.14 μmol L−1 when applied in the bath) or the Abcc inhibitor, MK571 was applied for one hour, during which DNP-SG was measured in the bath every 10 min in order to calculate mass-specific DNP-SG transport rate. MCLR significantly inhibited DNP-SG transport (p < 0.05), especially in middle intestine (47 and 24%, for luminal and serosal transport, respectively). In middle intestine strips, MCLR and MK571inhibited DNP-SG transport in a concentration dependent fashion (IC50 3.3 and 0.6 μmol L−1, respectively). In middle intestine strips incubated with calcein-AM (0.25 μmol L−1), calcein efflux was inhibited by MCLR (2.3 μmol L−1) and MK571 (3 μmol L−1) by 38 and 27%, respectively (p < 0.05). Finally, middle intestine segments were incubated with different concentrations of MCLR applied alone or together with 3 μM MK571. After one hour, protein phosphatase 1 (PP1) activity, the main target of MCLR, was measured. 2.5 μM MCLR did not produce any significant effect, while the same amount plus MK571 inhibited PP1 activity (p < 0.05). This effect was similar to that of 5 μM MCLR. Our results suggest that in O. hatcheri enterocytes MCLR is conjugated with GSH via GST and then exported to the intestinal lumen through Abcc-like transporters. This mechanism would protect the cell from MCLR toxicity, limiting toxin transport into the blood, which is probably mediated by basolateral Abccs. From an ecotoxicological point of view, elimination of MCLR through this mechanism would reduce the amount of toxin available for trophic transference.

Afiliación de los autores: Bieczynski, Flavia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

Afiliación de los autores: Torres, Walter Ramon. Provincia del Neuquen. Subsecretaria de Producción y Recursos Naturales. Centro de Ecología Aplicada del Neuquen; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Afiliación de los autores: Painefilú, Julio César. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

Afiliación de los autores: Castro, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

Afiliación de los autores: Bianchi, Virginia Angélica. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

Afiliación de los autores: Frontera, Jimena Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; Argentina

Afiliación de los autores: Paz, Dante Agustin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Fisiología, Biología Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Fisiología, Biología Molecular y Neurociencias; Argentina

Afiliación de los autores: González, Carolina. Agua y Saneamientos Argentinos; Argentina

Afiliación de los autores: Martín, Alejandro. Agua y Saneamientos Argentinos; Argentina

Afiliación de los autores: Villanueva, Silvina Stella Maris. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Fisiología Experimental. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Fisiología Experimental; Argentina

Afiliación de los autores: Luquet, Carlos Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina

Resumen:

Luego de la ingesta, el epitelio del intestino delgado está encargado de asimilar grandes cantidades de nutrientes, como aminoácidos, glúcidos y ácidos grasos. Las proteínas solubles que unen lípidos cumplirían un rol determinante en este proceso, sobre todo protegiendo la integridad del tejido contra el efecto simil-detergente de los ácidos grasos provenientes de la dieta. En enterocitos se expresan dos proteínas que unen ácidos grasos de cadena larga, IFABP y LFABP, para las cuales no se conocen bien aún sus funciones específicas, o el porqué de la necesidad de dos proteínas aparentemente equivalentes. Este laboratorio se ha enfocado en el estudio comparativo de estas dos proteínas empleando distintas variantes estructurales y métodos bioquímicos, biofísicos, y de biología molecular y celular. Así, se han podido definir los determinantes moleculares de cada proteína responsables de la interacción con membranas, los mecanismos de transferencia de ligandos y los factores que modulan estas propiedades. Más recientemente, se han extendido estos ensayos a cultivos celulares donde se ha correlacionado la expresión de estas proteínas con la secreción de citoquinas, la proliferación y la diferenciación celular. El estudio de estas proteínas es de gran importancia por su potencial como blancos terapéuticos y su utilidad en el diagnóstico de injurias tisulares.

After ingestion, the epithelium of the small intestine is responsible for assimilating large amounts of nutrients such as amino acids, sugars and fatty acids. Soluble lipid binding proteins fulfill a determining role in this process, especially protecting the tissue integrity against the detergent-like effect of fatty acids from the diet. Two proteins that bind long-chain fatty acids are expressed in enterocytes, IFABP and LFABP, whose specific functions are still poorly understood, or the reason for the need of two apparently equivalent proteins. Our laboratory has focused on the comparative study of these two proteins using structural variants and biochemical, biophysical, and molecular and cellular biology approaches. Thus, the molecular determinants responsible for the interaction with membranes were defined for each protein, their ligand transfer mechanism and the factors that modulate these properties. More recently, these assays have been extended to cell culture studies which correlate the expression of these proteins with cytokine secretion, cell proliferation and differentiation. The study of these proteins is of great importance due to their potential as therapeutic targets and their usefulness in the diagnosis of tissue injury.

Após a ingestão, o epitélio do intestino delgado é responsável pela assimilação de uma grande quantidade de nutrientes, tais como aminoácidos, glicídios e ácidos graxos. As proteínas solúveis que ligam lipídeos desempenhariam um papel determinante neste processo, principalmente protegendo a integridade do tecido contra o efeito detergente dos ácidos graxos da dieta. Nos enterócitos se expressam duas proteínas que ligam ácidos graxos de cadeia longa, IFABP e LFABP; cujas funções específicas ainda não são muito conhecidas, ou não se conhece o motivo pelo qual são necessárias duas proteínas aparentemente equivalentes. Nosso laboratório tem se focado no estudo comparativo destas duas proteínas utilizando variantes estruturais e métodos bioquímicos, biofísicos, e de biologia molecular e celular. Assim, foi possível definir os determinantes moleculares de cada proteína responsáveis pela interação com membranas, os mecanismos da transferência de ligantes e os fatores que modulam essas propriedades. Mais recentemente, estendemos estes ensaios para culturas celulares, correlacionando a expressão destas proteínas com a secreção de citocinas, a proliferação e a diferenciação celular. O estudo destas proteínas é de grande importância por seu potencial como alvos terapêuticos e sua utilidade no diagnóstico de lesões teciduais.

Afiliación de los autores: Falomir Lockhart, Lisandro Jorge. Max Planck Institute for Biophysical Chemistry. Laboratory of Cellular Dynamics; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; Argentina

Afiliación de los autores: Córsico, Betina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; Argentina

Afiliación de los autores: Franchini, Gisela Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; Argentina

Afiliación de los autores: de Gerónimo, Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; Argentina

Afiliación de los autores: Rodriguez Sawicki, Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; Argentina

Afiliación de los autores: Bottasso Arias, Natalia María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Bioquímicas de La Plata "Prof. Dr. Rodolfo R. Brenner". Universidad Nacional de la Plata. Facultad de Ciencias Médicas. Instituto de Investigaciones Bioquímicas de La Plata ; Argentina

Resumen:

The aim of this study was to investigate the impact of solid dispersions of polyethylene glycol 6000 (PEG 6000), using the co-precipitation method, on the in vitro solubility and intestinal absorption of praziquantel (PZQ). The solubility of PZQ in solid dispersions and physical mixtures was assessed in purified water and TC-199 buffer. The everted intestinal sac model was employed to assess, in vitro, intestinal absorption of PZQ. A significant enhancement in both in vitro solubility and intestinal absorption of PZQ was found in solid dispersions compared to pure PZQ and physical mixtures. This positive series of preliminary results showed that solid dispersion of PEG 6000 is a valuable strategy for increasing bioavailability of PZQ and could also prove useful for other poorly water-soluble drugs.

Colegio de Farmacéuticos de la Provincia de Buenos Aires