Cierre temprano del cartílago de crecimiento del tercer metacarpiano en potrillos Cuarto de Milla

A fin de evaluar el efecto de un suplemento dietario sobre el desarrollo óseo, se observó el estado inicial de los cartílagos de crecimiento de la epífisis distal del tercer metacarpiano de 19 potrancas Cuarto de Milla, de 6 a 9 meses de edad, mediante radiografías anteroposteriores de la articulación del nudo. El estudio radiológico se complementó con determinaciones en suero y orina de parámetros relacionados con el metabolismo óseo y mineral. El cierre del cartílago de crecimiento se clasificó de 1 a 5, cerrado a abierto respectivamente. El 26 % de las potrancas pertenecían al grupo 1, el 53% al grupo 2 y el 21 % al grupo 3. No se clasificó ninguna potranca en los grupos 4 y 5. Las potrancas de 6 a 8 meses dentro de los grupos 1 a 3 representaban el 84 % de los animales, siendo los ocho meses la edad que concentraba el 53 % de las potrancas. Se evidenció el cierre precoz de la placa de crecimiento del Mtc III, respecto de las edades que se citan en la bibliografía. El P sérico presentaban diferencias significativas entre el grupo 1 y 2 respecto del 3 (p< 0.05), siendo este valor más bajo en este último grupo. El Ca sérico también fue relativamente más bajo en este grupo, sin embargo las diferencias entre los tres grupos no resultaron significativas. Todas las potrancas presentaban valores de marcadores óseos elevados para la edad respecto de los valores medios considerados normales.As part of a study to assess the effect of a dietary supplement on bone development, the initial condition of the growth plate of the distal epiphysis of the third metacarpus of 19 Quarter Horse fillies, between 6 to 9 months of age, were evaluated by means of craniocaudal radiographs of the fetlock. The closure of the growth plates was determinate on the basis of: group 1, completed closure; group 2, 3/4 closure, group 3, ½ closure, group 4, 1/4 closure and group 5, completely open. Twenty six per cent of the fillies were in group 1, 53 % were in group 2 and 21 % were in group 3. No fillies were in groups 4 or 5. Fillies between 6 and 8 months in groups 1 to 3 represent 84 % of the animals. Fifty per cent of the fillies were 8 months old. The early closure of the growth plate of third metacarpal bone was evident with regard to the ages cited in the references. Serum phosphorus values were significant differences between groups 1 and 2, to 3 (

Variación del nivel de citoquinas en líquido sinovial de equinos con enfermedad articular tratados con bisfosfonatos

Osteoarthritis is one of the most common joint diseases in sport horses and is also cause of great economic losses associated. Early diagnosis of this disease, which sometimes is not feasible with radiographic studies, brings the possibility of early treatment in order to avoid greater commitment of underlying subchondral bone. While related cytokines play a physiological role in normal arthicular bone remodeling their increase may be considered pathological. This study postulates the determination of osteoarthicular cytokine levels (TNF-α, IL-1 β, IL-6, IL-4), as early diagnosis of osteoarthritis as well as for the evaluation of pamidronate, an aminobisphosphonates of second generation, post treatment OA evolution. We divided the animals in three groups that were classified according to the presence or not of joint disease and also considering degree of activity of OA and treatment response with bisphosphonates. As can be observed, the cytokines levels were elevated during active joint disease, and decreased after bisphosphonates treatment.La Osteoartritis es una de las artropatías más frecuentes en los equinos deportivos y es causa de grandes pérdidas económicas asociadas. El diagnóstico precoz de esta enfermedad, que en ocasiones no es factible con estudios radiográficos, deviene en la posibilidad de realizar un tratamiento temprano con el objeto de evitar mayor compromiso del hueso subcondral subyacente. Si bien ciertas citoquinas cumplen un rol fisiológico en el normal remodelado óseo y articular su incremento puede ser considerado patológico. En este estudio se postula el uso de la determinación de citoquinas de origen osteoarticular (TNF-α, IL-1β, IL-6, IL-4), para el diagnóstico de la osteoartritis así como para la evaluación de su evolución post tratamiento con pamidronato, aminobisfosfonato de segunda generación. Se trabajó con tres grupos de equinos de distintas edades, mayores de 4 años, clasificados según la presencia o no de enfermedad articular y el grado de actividad de la misma, para luego evaluar la respuesta al tratamiento con bisfosfonatos en los casos de enfermedad articular. Como pudo observarse, los niveles de citoquinas se encontraron elevados durante la enfermedad articular activa y las mismas disminuyeron su concentración post tratamiento con el bisfosfonato utilizado

Određivanje referentnih vrijednosti citokina i metaloproteinaza matriksa u sinovijalnoj tekućini konja različite dobi

Osteoarthritis (OA) is the most common joint disease in sport horses. Inflammatory and anti-inflammatory cytokines and metalloproteinases (MMPs) play a crucial role in the degradation of the cartilage extracellular matrix. The study of inflammatory molecular biomarkers could be useful in the diagnosis and choice of therapeutic strategies. However, little is known about the normal values of inflammatory biomarkers at different ages. Moreover, early diagnosis of OA is crucial to ensure early treatment in order to prevent chronic damage. The aim of this study was to establish a reference range for values of pro-inflammatory cytokines (IL-1β, IL-4, IL-6 and TNF-α) and MMPs (MMP-2 and MMP-9) in the synovial fluid of horses of different ages. The old horses group presented higher values of IL-4 and TNF-α than the rest of the groups studied (P<0.001 vs. all other groups). IL-1β levels were higher in foals than in all the other groups (P<0.001). No statistically significant differences were found between the groups as regards the mean IL-6 values. Synovial MMP-2 levels were statistically lower in the old horses group (P<0.001) and higher in the foals group (P<0.05). Higher MMP-9 levels were found in the foals group (55.45 ± 58.1 percentage of proteolysis) (P<0.001 vs. all other groups). This study demonstrates the existence of variations in the levels of pro-inflammatory markers in the synovial fluid of horses at different agesOsteoartritis (OA) je najčešća bolest zglobova u sportskih konja. Upalni i protuupalni citokini te metaloproteinaze (MMP) imaju ključnu ulogu u degradaciji izvanstaničnog matriksa hrskavice. Istraživanje molekularnih biomarkera upale moglo bi biti korisno u dijagnostici i izboru strategija za liječenje. No, malo se zna o normalnim vrijednostima upalnih biomarkera u različitoj dobi. Štoviše, rana dijagnoza OA ključna je za osiguranje ranog liječenja, kako bi se spriječilo kronično oštećenje. Cilj ovoga rada bio je utvrditi referentni raspon vrijednosti proupalnih citokina (IL-1β, IL-4, IL-6 i TNF-a) i MMP-a (MMP-2 i MMP-9) u sinovijalnoj tekućini konja različite dobi. Skupina starih konja pokazala je veće vrijednosti IL-4 i TNF-α od ostalih istraženih skupina (P<0,001 u odnosu na sve ostale skupine). Razina IL-1β bila je viša u ždrebadi nego u svim ostalim skupinama (P<0,001). Nije bilo statistički značajne razlike među skupinama u odnosu na prosječne vrijednosti IL-6. Razina MMP-2 u sinoviji bila je statistički niža u skupini starih konja (P<0,001) i više u skupini ždrebadi (P<0,05). Visoke razine MMP-9 pronađene su u skupini ždrebadi (55,45 ± 58,1 % proteolize) (P<0,001 u odnosu na sve ostale skupine). Ovaj rad pokazuje postojanje varijacija u razinama proupalnih markera u sinovijalnoj tekućini konja različite dobi

Hemoglobin Interlaken in combination with beta thalassemia trait

We report a rare a1 globin gene variant (Hb Interlaken) found in a 63-year-old woman of Italian ancestry living in Buenos Aires Province, Argentina. The variant, a missense mutation at cd15 (GGT → GAT) causing a Gly →Asp amino acid substitution and also known as Hb J Oxford, was found in combination with the common thalassemia trait cd 39 (C→T). The clinical picture of the patient was that of a b-thalassemia trait.Fil: Ojeda, Mara Jorgelina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Fisiología Experimental (i); ArgentinaFil: Perez, Susana M.. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; ArgentinaFil: Calvo, Karina Lucrecia. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; ArgentinaFil: Pratti, Arianna F.. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; ArgentinaFil: Voss, María E.. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; ArgentinaFil: Milani, Angela Cristina. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; ArgentinaFil: Chiappe, Gustavo. Unidad Asistencial "Dr. César Milstein"; ArgentinaFil: Erramouspe, Beatriz. Unidad Asistencial "Dr. César Milstein"; ArgentinaFil: Bragós, Irma M.. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas; Argentin

Myocardial reperfusion injury: Reactive oxygen species vs. NHE-1 reactivation

Background/Aims: Flow restoration to ischemic myocardium reduces infarct size (IS), but it also promotes reperfusion injury. A burst of reactive oxygen species (ROS) and/or NHE-1 reactivation were proposed to explain this injury. Our study was aimed to shed light on this unresolved issue. Methods: Regional infarction (40 min-ischemia/2 hs-reperfusion) was induced in isolated and perfused rat hearts. Maximal doses of N-(2-mercaptopropionyl)-glycine (MPG 2mmol/L, ROS scavenger), cariporide (10μmol/L, NHE-1 inhibitor), or sildenafil (1μmol/L, phosphodiesterase5A inhibitor) were applied at reperfusion onset. Their effects on IS, myocardial concentration of thiobarbituric acid reactive substances (TBARS), ERK1/2, p90RSK, and NHE-1 phosphorylation were analyzed. Results: All treatments decreased IS ∼ 50% vs. control. No further protection was obtained by combining cariporide or MPG with sildenafil. Myocardial TBARS increased after infarction and were decreased by MPG or cariporide, but unaffected by sildenafil. In line with the fact that ROS induce MAPK-mediated NHE-1 activation, myocardial infarction increased ERK1/2, p90RSK, and NHE-1 phosphorylation. MPG and cariporide cancelled these effects. Sildenafil did not reduce the phosphorylated ERK1/2-p90RSK levels but blunted NHE-1 phosphorylation suggesting a direct dephosphorylating action. Conclusions: 1) Reperfusion injury would result from ROS-triggered MAPK-mediated NHE-1 phosphorylation (and reactivation) during reperfusion; 2) sildenafil protects the myocardium by favouring NHE-1 dephosphorylation and bypassing ROS generation.Facultad de Ciencias MédicasCentro de Investigaciones Cardiovasculare

The Anrep effect requires transactivation of the epidermal growth factor receptor

Myocardial stretch elicits a biphasic contractile response: the Frank-Starling mechanism followed by the slow force response (SFR) or Anrep effect. In this study we hypothesized that the SFR depends on epidermal growth factor receptor (EGFR) transactivation after the myocardial stretch-induced angiotensin II (Ang II)/endothelin (ET) release. Experiments were performed in isolated cat papillary muscles stretched from 92 to 98% of the length at which maximal twitch force was developed (Lmax). The SFR was 123 ± 1% of the immediate rapid phase (n = 6, P < 0.05) and was blunted by preventing EGFR transactivation with the Src-kinase inhibitor PP1 (99 ± 2%, n = 4), matrix metalloproteinase inhibitor MMPI (108 ± 4%, n = 11), the EGFR blocker AG1478 (98 ± 2%, n = 6) or the mitochondrial transition pore blocker clyclosporine (99 ± 3%, n = 6). Stretch increased ERK1/2 phosphorylation by 196 ± 17% of control (n = 7, P < 0.05), an effect that was prevented by PP1 (124 ± 22%, n = 7) and AG1478 (131 ± 17%, n = 4). In myocardial slices, Ang II (which enhances ET mRNA) or endothelin-1 (ET-1)-induced increase in O2- production (146 ± 14%, n = 9, and 191 ± 17%, n = 13, of control, respectively, P < 0.05) was cancelled by AG1478 (94 ± 5%, n = 12, and 98 ± 15%, n = 8, respectively) or PP1 (100 ± 4%, n = 6, and 99 ± 8%, n = 3, respectively). EGF increased O2- production by 149 ± 4% of control (n = 9, P < 0.05), an effect cancelled by inhibiting NADPH oxidase with apocynin (110 ± 6% n = 7), mKATP channels with 5-hydroxydecanoic acid (5-HD; 105 ± 5%, n = 8), the respiratory chain with rotenone (110 ± 7%, n = 7) or the mitochondrial permeability transition pore with cyclosporine (111 ± 10%, n = 6). EGF increased ERK1/2 phosphorylation (136 ± 8% of control, n = 9, P < 0.05), which was blunted by 5-HD (97 ± 5%, n = 4), suggesting that ERK1/2 activation is downstream of mitochondrial oxidative stress. Finally, stretch increased Ser703 Na+/H+ exchanger-1 (NHE-1) phosphorylation by 172 ± 24% of control (n = 4, P < 0.05), an effect that was cancelled by AG1478 (94 ± 17%, n = 4). In conclusion, our data show for the first time that EGFR transactivation is crucial in the chain of events leading to the Anrep effect.Facultad de Ciencias Médica

Myocardial reperfusion injury: Reactive oxygen species vs. NHE-1 reactivation

Background/Aims: Flow restoration to ischemic myocardium reduces infarct size (IS), but it also promotes reperfusion injury. A burst of reactive oxygen species (ROS) and/or NHE-1 reactivation were proposed to explain this injury. Our study was aimed to shed light on this unresolved issue. Methods: Regional infarction (40 min-ischemia/2 hs-reperfusion) was induced in isolated and perfused rat hearts. Maximal doses of N-(2-mercaptopropionyl)-glycine (MPG 2mmol/L, ROS scavenger), cariporide (10μmol/L, NHE-1 inhibitor), or sildenafil (1μmol/L, phosphodiesterase5A inhibitor) were applied at reperfusion onset. Their effects on IS, myocardial concentration of thiobarbituric acid reactive substances (TBARS), ERK1/2, p90RSK, and NHE-1 phosphorylation were analyzed. Results: All treatments decreased IS ∼ 50% vs. control. No further protection was obtained by combining cariporide or MPG with sildenafil. Myocardial TBARS increased after infarction and were decreased by MPG or cariporide, but unaffected by sildenafil. In line with the fact that ROS induce MAPK-mediated NHE-1 activation, myocardial infarction increased ERK1/2, p90RSK, and NHE-1 phosphorylation. MPG and cariporide cancelled these effects. Sildenafil did not reduce the phosphorylated ERK1/2-p90RSK levels but blunted NHE-1 phosphorylation suggesting a direct dephosphorylating action. Conclusions: 1) Reperfusion injury would result from ROS-triggered MAPK-mediated NHE-1 phosphorylation (and reactivation) during reperfusion; 2) sildenafil protects the myocardium by favouring NHE-1 dephosphorylation and bypassing ROS generation.Facultad de Ciencias MédicasCentro de Investigaciones Cardiovasculare

Mitochondrial reactive oxygen species activate the slow force response to stretch in feline myocardium

When the length of the myocardium is increased, a biphasic response to stretch occurs involving an initial rapid increase in force followed by a delayed slow increase called the slow force response (SFR). Confirming previous findings involving angiotensin II in the SFR, it was blunted by AT1 receptor blockade (losartan). The SFR was accompanied by an increase in reactive oxygen species (ROS) of ∼30% and in intracellular Na+ concentration ([Na⁺]i) of ∼2.5 mmol l⁻¹ over basal detected by H2DCFDA and SBFI fluorescence, respectively. Abolition of ROS by 2-mercapto-propionyl-glycine (MPG) and EUK8 suppressed the increase in [Na⁺]i and the SFR, which were also blunted by Na⁺/H⁺ exchanger (NHE-1) inhibition (HOE642). NADPH oxidase inhibition (apocynin or DPI) or blockade of the ATP-sensitive mitochondrial potassium channels (5HD or glybenclamide) suppressed both the SFR and the increase in [Na⁺]i after stretch, suggesting that endogenous angiotensin II activated NADPH oxidase leading to ROS release by the ATP-sensitive mitochondrial potassium channels, which promoted NHE-1 activation. Supporting the notion of ROS-mediated NHE-1 activation, stretch increased the ERK1/2 and p90rsk kinases phosphorylation, effect that was cancelled by losartan. In agreement, the SFR was cancelled by inhibiting the ERK1/2 signalling pathway with PD98059. Angiotensin II at a dose that mimics the SFR (1 nmol l⁻¹) induced an increase in ·O₂− production of ∼30–40% detected by lucigenin in cardiac slices, an effect that was blunted by losartan, MPG, apocynin, 5HD and glybenclamide. Taken together the data suggest a pivotal role of mitochondrial ROS in the genesis of the SFR to stretch.Centro de Investigaciones Cardiovasculare

Indicadores de sustentabilidad para las cadenas de bioenergía en Uruguay

Un objetivo de la Agroecología es brindar información relevante para la toma de decisiones a nivel predial y nacional para la generación de políticas públicas. En Uruguay, el Ministerio de Industria, Energía y Minería está considerando promover la producción de energía alternativa a partir de biomasa de diferentes fuentes. Los indicadores de sostenibilidad definidos por GBEP (Global Bioenergy Partnership) para las cadenas de producción de bioenergía pueden ser una herramienta útil para fortalecer la toma de decisiones en materia de políticas energéticas. En este trabajo se presenta una evaluación de pertinencia y aplicabilidad de los 24 indicadores de sustentabilidad propuestos por la GBEP para evaluar el proceso de producción de Bioenergía en base a residuos de biomasa forestal, producción de biodiesel y producción de bioetanol en Uruguay. Se identificaron indicadores pertinentes, y necesidades de reformulación de algunos indicadores, desde una perspectiva agroecológica.One of the goals of Agroecology is to offer relevant information for decision making at the farm and national levels to generate public policy. In Uruguay, the Ministry of Industry, Energy, and Mining, is considering to promote the production of alternative energy from biomass from different sources. Sustainability indicators defined by GBEP (Global Bioenergy Partnership) for bioenergy production chains can be a tool to strengthen the decision making in energy policy. In this paper we present an evaluation of relevance and feasibility of the 24 sustainability indicators proposed by GBEP to evaluate bioenergy production from forest residues, biodiesel and bioethanol in Uruguay. Relevant indicators were identified, as well as the need to reformulate some of these, from an agroecological perspective.Eje A4: Ambiente, Naturaleza y AgroecologíaFacultad de Ciencias Agrarias y Forestale

Influence of Na+-Independent Cl¯-HCO3¯ Exchange on the Slow Force Response to Myocardial Stretch

Previous work demonstrated that the slow force response (SFR) to stretch is due to the increase in calcium transients (Ca2+T) produced by an autocrine-paracrine mechanism of locally produced angiotensin II/endothelin activating Na+-H+ exchange. Although a rise in pHi is presumed to follow stretch, it was observed only in the absence of extracellular bicarbonate, suggesting pHi compensation through the Na+-independent Cl¯-HCO3¯ exchange (AE) mechanism. Because available AE inhibitors do not distinguish between different bicarbonate-dependent mechanisms or even between AE isoforms, we developed a functional inhibitory antibody against both the AE3c and AE3fl isoforms (anti-AE3Loop III) that was used to explore if pHi would rise in stretched cat papillary muscles superfused with bicarbonate after AE3 inhibition. In addition, the influence of this potential increase in pHi on the SFR was analyzed. In this study, we present evidence that cancellation of AE3 isoforms activity (either by superfusion with bicarbonate-free buffer or with anti-AE3Loop III) results in pHi increase after stretch and the magnitude of the SFR was larger than when AE was operative, despite of similar increases in [Na+]i and Ca2+T under both conditions. Inhibition of reverse mode Na+-Ca2+ exchange reduced the SFR to the half when the AE was inactive and totally suppressed it when AE3 was active. The difference in the SFR magnitude and response to inhibition of reverse mode Na+-Ca2+ exchange can be ascribed to a pHi-induced increase in myofilament Ca2+ responsiveness.Facultad de Ciencias MédicasCentro de Investigaciones Cardiovasculare