CATASTROPHIC MUSCULOSKELETAL INJURIES IN THOROUGHBRED HORSES, CARACAS-VENEZUELA

Se hizo un estudio clínico-patológico de las lesiones músculo-esqueléticas catastróficas ocurridas en pruebas públicas en el Hipódromo “La Rinconada”, Caracas, Venezuela, entre el 2000 al 2007. Se trabajó con 78 equinos Pura Sangre de Carrera con lesiones del aparato locomotor. Se colectó muestras de sangre para estudio hematológico, bioquímico y hormonal (paratohormona), así como muestras de orina para determinar niveles de fosfatos. Se les practicó la eutanasia debido a la severidad de las lesiones y se realizó la necropsia. Se tomó secciones de tejido óseo para determinación de calcio y fósforo, y de tejido muscular, tendinoso, gástrico, renal y hepático para estudio histológico. Los exámenes clínicos revelaron claudicación grado IV-V en todos los animales. La pérdida de continuidad ósea (fracturas) ocurrió en todos los casos, y exposición de estructuras óseas, articulares, rupturas de tendones, ligamentos y compromiso vascular en el 60%. Las fracturas fueron de tipo multifragmentaria (60%), oblicua (25%) y espiral (15%). Los valores sanguíneos y de orina estuvieron afectados. En la necropsia se observó el síndrome ulceroso gástrico equino, congestión hepática y necrosis tubular aguda renal. El análisis histológico reveló gastritis aguda superficial severa, úlceras gástricas, necrosis periacinar hepática, osteomalacia y necrosis del hueso subcondral, condromalacia y capsulitis severa.A clinical and pathological study was conducted on musculoskeletal catastrophic lesions of the locomotive apparatus occurred in 78 Thoroughbred horses in the racetrack «La Rinconada», Caracas, Venezuela, during 2000 to 2007. Blood samples were collected for hematological, biochemical and parathormone analysis in blood. Also, urine samples for phosphate levels. All animals were euthanized due to severe lesions, and bone, tendons, stomach, kidney and liver samples were taken for by histopathology evaluation. Clinical exams revealed lameness grade IV-V in all animals. Losses of bone continuity (fracture) occurred in all cases, and exposition of bone structures, joint damage, rupture of tendons and ligaments and vascular destruction were observed in 60% of them. The types of fractures were comminuted (60%), oblique (25%) and spiral (15%). Blood and urine values were affected. Necropsy showed equine gastric ulcer syndrome, liver congestion and renal acute tubular necrosis. Histopathological analysis showed acute and severe gastritis, gastric ulcers, hepatic periacinar necrosis, osteomalacia and necrosis in subchondral bone, chondromalacia and severe capsulitis

LESIONES GÁSTRICAS, HEPÁTICAS Y RENALES EN EL SÍNDROME DE ÚLCERAS GÁSTRICAS EN EQUINOS PURA SANGRE DE CARRERA.

The aim of this study was to describe gastric, hepatic, and renal lesions inThoroughbred Racing horses associated to the equine gastric ulcer syndrome. Thirtyhorses with a history of gastric ulcer syndrome and recurrent colic during 2006 to 2007 atthe Race Track «La Rinconada», Caracas, Venezuela were evaluated. Horses were euthanized and the necropsy was conducted. Tissue samples were collected from stomach,liver and kidney, and processed by conventional histological methods. In the stomach,the mucosa was intact but areas of hyperaemia and hyperkeratosis were observed in 6cases, multifocal small erosions or ulcers in 6 cases, multifocal large ulcers with areas ofextensive erosion in 12 cases and extensive areas of ulceration with exposure of thesubmucosa in 6 cases. The macroscopic evaluation of the liver showed evidenthepatomegaly in 22 cases and lobular pattern in 18 cases. The kidneys showed severecongestion in all cases, loss of cortico-medullar ratio in 20 cases, cortical necrosis in 18cases, acute tubular necrosis in all cases, papillary necrosis in 6 cases, and adherence ofthe capsule with interstitial fibroplasia in 4 cases. Lesions in the gastric mucosa, liver andkidney were associated with extended treatment with non-steroidal anti-inflammatorydrugsEl objetivo del estudio fue describir lesiones gástricas, hepáticas y renales en caballos Pura Sangre de Carreras enmarcadas en el síndrome ulceroso gástrico equino. Se trabajó con 30 ejemplares Pura Sangre de Carrera con historia de síndrome ulceroso gástrico y cólico recurrentes entre 2006 y 2007, en el Hipódromo «La Rinconada», Caracas, Venezuela. A los animales se les practicó la eutanasia y se colectó nuestras de tejido gástrico, hepático y renal. Las muestras fueron procesadas por los métodos histológicos convencionales. En el estómago se observó mucosa intacta, pero con áreas de hiperemia y/o hiperqueratosis en 6 casos, pequeñas erosiones multifocales o úlceras en 30 casos, úlceras grandes multifocales con regiones extensas de erosión en 12 casos, y úlceras extensivas con áreas de exposición de la submucosa en 6 casos. La evaluación macroscópica del hígado evidenció icteria en 22 casos, así como hepatomegalia y patrón lobulillar en 18 casos. Los riñones mostraron congestión severa en todos los casos, pérdida de la relación córtico medular en 20 casos, necrosis cortical 18 casos, necrosis tubular aguda en todos los casos, necrosis papilar confluente en 6 casos y adherencia de la cápsula con fibroplasia intersticial en 4 casos. Las lesiones observadas en la mucosa gástrica, hígado y riñón estuvieron asociadas con terapéuticas prolongadas con antiinflamatorios no esteroideos

Orientation dependent molecular electrostatics drives efficient charge generation in homojunction organic solar cells

Organic solar cells usually utilise a heterojunction between electron-donating (D) and electron-accepting (A) materials to split excitons into charges. However, the use of D-A blends intrinsically limits the photovoltage and introduces morphological instability. Here, we demonstrate that polycrystalline films of chemically identical molecules offer a promising alternative and show that photoexcitation of α-sexithiophene (α-6T) films results in efficient charge generation. This leads to α-6T based homojunction organic solar cells with an external quantum efficiency reaching up to 44% and an open-circuit voltage of 1.61 V. Morphological, photoemission, and modelling studies show that boundaries between α-6T crystalline domains with different orientations generate an electrostatic landscape with an interfacial energy offset of 0.4 eV, which promotes the formation of hybridised exciton/charge-transfer states at the interface, dissociating efficiently into free charges. Our findings open new avenues for organic solar cell design where material energetics are tuned through molecular electrostatic engineering and mesoscale structural control

Population-Specific Responses to Interspecific Competition in the Gut Microbiota of Two Atlantic Salmon (Salmo salar) Populations

The gut microbial community in vertebrates plays a role in nutrient digestion and absorption, development of intestine and immune systems, resistance to infection, regulation of bone mass and even host behavior and can thus impact host fitness. Atlantic salmon (Salmo salar) reintroduction efforts into Lake Ontario, Canada, have been unsuccessful, likely due to competition with non-native salmonids. In this study, we explored interspecific competition effects on the gut microbiota of two Atlantic salmon populations (LaHave and Sebago) resulting from four non-native salmonids. After 10 months of rearing in semi-natural stream tanks under six interspecific competition treatments, we characterized the gut microbiota of 178 Atlantic salmon by parallel sequencing the 16S rRNA gene. We found 3978 bacterial OTUs across all samples. Microbiota alpha diversity and abundance of 27 OTUs significantly differed between the two populations. Interspecific competition reduced relative abundance of potential beneficial bacteria (six genera of lactic acid bacteria) as well as 13 OTUs, but only in the LaHave population, indicating population-specific competition effects. The pattern of gut microbiota response to interspecific competition may reflect local adaptation of the host-microbiota interactions and can be used to select candidate populations for improved species reintroduction success

Impact of a probiotic fermented milk in the gut ecosystem and in the systemic immunity using a non-severe protein-energy-malnutrition model in mice

<p>Abstract</p> <p>Background</p> <p>Malnutrition affects the immune response, causing a decrease of defence mechanisms and making the host more susceptible to infections. Probiotics can reconstitute the intestinal mucosa and stimulate local and systemic immunity. The aim of this work was evaluate the effects of a probiotic fermented milk as a complement of a re-nutrition diet, on the recovery of the intestinal barrier, and mucosal and systemic immune functions in a murine model of non-severe protein-energy-malnutrition. Its potential protection against <it>Salmonella enterica </it>serovar Typhimurium (<it>S</it>. Typhimurium) infection was also analyzed.</p> <p>Methods</p> <p>Mice were undernourished and divided into 3 groups according to the dietary supplement received during re-nutrition (milk, probiotic fermented milk or its bacterial free supernatant) and compared to well-nourished and malnourished mice. They were sacrificed previous to the re-nutrition and 5 days post re-nutrition. The phagocytic activity of macrophages from spleen and peritoneum and the changes in the intestinal histology and microbiota were evaluated. Different immune cell populations and cytokine productions were analyzed in the small intestine tissues. The effect of the re-nutrition supplements on the systemic immunity using OVA antigen and against an infection with <it>S. </it>Typhimurium was also studied.</p> <p>Results</p> <p>Probiotic fermented milk was the most effective re-nutrition diet that improved the intestinal microbiota. Its administration also increased the number of IgA+ cells, macrophages and dendritic cells. The production of different cytokine (IFN-γ, TNF-α, IL-12) by these cells and the phagocytic activity in peritoneum and spleen was also increased. This re-nutrition diet also stimulated the systemic immune response against OVA antigen which was diminished after the malnutrition period and also improved the host response against <it>S. </it>Typhimurium, decreasing the spread of pathogenic bacteria to the liver and the spleen. The importance of the metabolites released during milk fermentation was also demonstrated through the analysis of the bacterial free supernatant obtained from the probiotic fermented milk, but the whole product showed the best effects in the parameters evaluated in this study.</p> <p>Conclusions</p> <p>The administration of probiotic fermented milk as a dietary supplement during the re-nutrition process in a murine immunodeficiency model by malnutrition could be a good adjuvant diet to improve the gut and systemic immune response for the protection against <it>Salmonella </it>infection.</p

Host immunity in the protective response to nasal immunization with a pneumococcal antigen associated to live and heat-killed Lactobacillus casei

Background: At present, available pneumococcal vaccines have failed to eradicate infections caused by S. pneumoniae. Search for effective vaccine continues and some serotype independent pneumococcal proteins are considered as candidates for the design of new vaccines, especially a mucosal vaccine, since pneumococci enter the body through mucosal surfaces. Selection of the appropriate adjuvant is important for mucosal vaccines, and lactic acid bacteria (LAB) with immunostimulant properties are promissory candidates. In this work, we assessed the adjuvant effect of a probiotic strain, Lactobacillus casei (L. casei), when nasally administered with a pneumococcal antigen (pneumococcal protective protein A: PppA) for the prevention of pneumococcal infection. Adjuvanticity of both live (LcV) and heat-killed (LcM) was evaluated and humoral and cellular antigen-specific immune response was assessed in mucosal and systemic compartments. The potential mechanisms induced by nasal immunization were discussed.Results: Nasal immunization of young mice with PppA+LcV and PppA+LcM induced anti-PppA IgA and IgG antibodies in mucosal and systemic compartments and levels of these specific antibodies remained high even at day 45 after the 3rd Immunization (3rd I). These results were correlated with IL-4 induction by the mixture of antigen plus LcV and LcM. Also, PppA+Lc (V and M) induced stimulation of Th1 and Th17 cells involved in the defence against pneumococci. The protection against pneumococcal respiratory challenge at day 30 after the 3rd I showed that PppA+LcV and PppA+LcM immunizations significantly reduced pathogen counts in nasal lavages while prventing their passage into lung and blood. Survival of mice immunized with the co-application of PppA plus LcV and LcM was significantly higher than in mice immunized with PppA alone and control mice when intraperitoneal challenge was performed. No significant differences between the treatments involving LcV and LcM were found.Conclusions: Live and heat-killed L. casei enhanced the antigen-specific immune response when administered nasally with a pneumococcal antigen. Considering the potential risk associated with live bacteria, the design of a nasal vaccine based on pneumococcal antigens and heat-killed L. casei emerges as a safe and effective strategy for the prevention of pneumococcal infections and opens new possibilities of application of dead LAB as adjuvants in vaccine formulations against other pathogens.Fil: Vintiñi, Elisa Ofelia. Universidad Nacional de Tucumán. Facultad de Agronomía y Zootecnia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Medina, Marcela Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; Argentin

The Probiotic Bacterium Lactobacillus casei Induces Activation of the Gut Mucosal Immune System through Innate Immunity

The mechanisms by which probiotic bacteria affect the immune system are unknown yet, but many of them are attributed to an increase in the innate or in the acquired immune response. To study the influence of the probiotic bacterium Lactobacillus casei in the expression of receptors involved in the innate immune response, this bacterium was orally administered to BALB/c mice. After, they were sacrificed; the small intestine and intestinal fluids were collected to measure secretory immunoglobulin A (IgA) specific for L. casei. Mononuclear cells from Peyer's patches were isolated to determine the CD-206 and TLR-2 receptors. In histological slices we determined the number of IgA(+), CD4(+), CD8(+), and CD3(+) cells and two cytokines (interleulin-5 [IL-5] and IL-6). CD-206 and TLR-2 increased with respect to the untreated control. We did not observe an increase in the T population or in the IL-5-positive cells. IgA(+) cells and IL-6-producing cells increased after 7 days of L. casei administration. We did not find specific antibodies against L. casei. The main immune cells activated after oral L. casei administration were those of the innate immune response, with an increase in the specific markers of these cells (CD-206 and TLR-2), with no modification in the number of T cells