Seasonal variations of melatonin in ram seminal plasma are correlated to those of testosterone and antioxidant enzymes

<p>Abstract</p> <p>Background</p> <p>Some breeds of sheep are highly seasonal in terms of reproductive capability, and these changes are regulated by photoperiod and melatonin secretion. These changes affect the reproductive performance of rams, impairing semen quality and modifying hormonal profiles. Also, the antioxidant defence systems seem to be modulated by melatonin secretion, and shows seasonal variations. The aim of this study was to investigate the presence of melatonin and testosterone in ram seminal plasma and their variations between the breeding and non-breeding seasons. In addition, we analyzed the possible correlations between these hormones and the antioxidant enzyme defence system activity.</p> <p>Methods</p> <p>Seminal plasma from nine Rasa Aragonesa rams were collected for one year, and their levels of melatonin, testosterone, superoxide dismutase (SOD), glutathione reductase (GRD), glutathione peroxidase (GPX) and catalase (CAT) were measured.</p> <p>Results</p> <p>All samples presented measurable quantities of hormones and antioxidant enzymes. Both hormones showed monthly variations, with a decrease after the winter solstice and a rise after the summer solstice that reached the maximum levels in October-November, and a marked seasonal variation (P < 0.01) with higher levels in the breeding season. The yearly pattern of GRD and catalase was close to that of melatonin, and GRD showed a significant seasonal variation (P < 0.01) with a higher activity during the breeding season. Linear regression analysis between the studied hormones and antioxidant enzymes showed a significant correlation between melatonin and testosterone, GRD, SOD and catalase.</p> <p>Conclusions</p> <p>These results show the presence of melatonin and testosterone in ram seminal plasma, and that both hormones have seasonal variations, and support the idea that seasonal variations of fertility in the ram involve interplay between melatonin and the antioxidant defence system.</p

Prevalencia en nuestro medio de las deformidades dinámicas posicionales del hallux como secuela de las fracturas de tercio medio y distal de tibia

Dynamic positional deformity of the hallux is a relatively new disease, precisely because of its innovative nature and dynamics may go unnoticed to clinicians. It is because of this, that the limited literature available stresses the importance of making an active search for this pathology in our daily practice. The purpose of this study is to estimate the prevalence of these deformities at the University Hospital Dr. Peset of Valencia as well as make an analysis of their management. An analytical, descriptive and retrospective study was designed in which patients admitted in our center during 2014 and 2015 with medium and distal third tibia fracture were analyzed searching for dynamics positional deformities of the hallux. We found a total of 5 compatible cases from 42 analyzed tibia fractures. This may indicate that as expected dynamic positional deformity of the hallux could be an underrated disease in our medium

Fracturas de Astrágalo: Evaluación Clínico-Quirúrgica

Se han revisado 13 pacientes diagnosticados de fractura de astrágalo recogidos en nuestro Servicio de Urgencias y tratados quirúrgicamente en todos los casos. De ellos se ha realizado un seguimiento clínico y radiológico. En el 46% de los casos se obtuvieron resultados satisfactorios (23% excelentes y 23% buenos). Los restantes se repartieron entre regulares (38%) y malos (16%). La necrosis avascular apareció en 3 de los 13 casos, discutiéndose el origen de esta seria complicación. Siguiendo la clasificación de WEBER, los tipos de fractura más frecuentes fueron el tipo III (38%) y el II (31%). La congruencia articular postquirúrgica del astrágalo fracturado y el tiempo de demora en la cirugía que debe ser de urgencia, se muestran como factores a considerar en la evolución ulterior del "Aviators astragalus". Se discute así mismo el valor del signo de Hawkins.Areview of 13 patients diagnosed of Talus fracture has been colected in our service of trauma emergency. All of them have been managed by surgical methods and clinical and radiologically followed up. Satisfactory results wer e obtained in 46% of the cases (23%, excellents and 23%, good results). The rest wer e regular (38%) and bad (16%). Avascular necrosis was observed in 3 of the 13 cases, discussing the origin of this serious complication. The most frequent types of fracture were type III (38%) ant type II (31%) following Weber's classification. The postsurgical articular congruency of the fractured talus and the delayed time on the surgery which must be an emergency, seem to be factors to conside r in the later evolution of the "aviators astragalus". The value of Hawkins sign is also discussed

Indicaciones Límite de las Fracturas de Húmero con Clavo Endomedular Cerrojado

El tratamiento de las fracturas diafisarias del húmero ha entrado en controversia en los últimos años, como lo refleja la literatura internacional. La problemática aumenta cuando se trata de fracturas diafisarias límites que alcanzan la zona metafisaria superior e inferior. En un intento de mejora terapéutica este grupo de autores ha testado un clavo cerrojado para el húmero diseñado por Seidel. El promedio de seguimiento ha sido de 12 meses con un mínimo de 6 meses. El número de casos evaluados ha sido 6. Siguiendo la cotación de Stewart, 4 de los seis pacientes obtuvieron resultados buenos o excelentes. Todos los pacientes consolidaron sus fracturas en un período de tiempo normal, entre 3 y 5 meses, con una media de 4 meses, 4 de los seis pacientes no se inmovilizaron con yeso en ningún momento. La bondad y sencillez del método hace augurar buenos resultados en otros grupos ampliando sus indicaciones.Treatment of dyaphyseal fractures of the humerus has been the source of considerable controversy in recent years. The problem increases in dimension when one is dealing with limiting diaphyseal fractures that invole the upper and lower metaphyseal zone. In an attempt to improve the therapy of this circunstance, the members of this research team have tested a locking nail for the humerus designed by Seidel. The mean follow-up time has been 12 months, with a minimum of six months. The number of cases evaluated was 6. According to the scale of Stewart, four of the cases obtained good or excellent results. All the patients consolidated their fractures within a normal period of time -between 3 and 5 months-, with a mean of 4 months. Four of the 6 patients wer e not immobilized with paster at any time. The goodness and simplicity of the method are suggestive of promising results in other groups by broadening its indications

Melatonin receptors MT1 and MT2 are expressed in spermatozoa from several seasonal and nonseasonal breeder species

P. 1958-1968Melatonin is a ubiquitous and multipurpose molecule, and one of its roles is to regulate reproduction in some seasonal mammals. Our group has previously reported the variation in the melatonin levels in ram seminal plasma along the year and identified MT1 and MT2 receptors in ram spermatozoa. The objective of this study was to elucidate whether the presence of melatonin receptors (MT1 and MT2) in the sperm plasma membrane, and melatonin in the seminal plasma is related to seasonal breeding. For this purpose, the presence of melatonin receptors and the levels of melatonin in seminal plasma have been examined in several species: donkey and stallion as long-day breeders; red deer as a wild, short-day, highly seasonal breeder (epididymal spermatozoa); bull as a conventional nonseasonal breeder; boar as a seasonal breeder under management techniques; and dog as possible a seasonal breeder not regulated by melatonin. We have detected measurable levels of melatonin in the seminal plasma of all ejaculated semen samples (from donkey, stallion, boar, bull, and dog). Also, and for the first time, we have demonstrated the presence of MT1 and MT2 melatonin receptors in the spermatozoa of all these species, regardless their type of reproduction or sperm source (ejaculated or epididymal), using indirect immunofluorescence techniques and Western blotting. Our findings suggest that melatonin and melatonin receptors may be universally distributed in the reproductive system of mammals and that the sperm melatonin receptors cells may not be necessarily related with seasonal reproduction. Furthermore, the presence of MT1 at the cytoplasmic droplet in immature ejaculated stallion spermatozoa found in one sample and epididymal red deer spermatozoa suggests that melatonin may be involved in specific functions during spermatogenesis and sperm maturation, like protecting spermatozoa from oxidative damage, this activity being mediated through these receptors.S

patrimonio intelectual

Actas de congresoLas VI Jornadas se realizaron con la exposición de ponencias que se incluyeron en cuatro ejes temáticos, que se desarrollaron de modo sucesivo para facilitar la asistencia, el intercambio y el debate, distribuidos en tres jornadas. Los ejes temáticos abordados fueron: 1. La enseñanza como proyecto de investigación. Recursos de enseñanza-aprendizaje como mejoras de la calidad educativa. 2. La experimentación como proyecto de investigación. Del ensayo a la aplicabilidad territorial, urbana, arquitectónica y de diseño industrial. 3. Tiempo y espacio como proyecto de investigación. Sentido, destino y usos del patrimonio construido y simbólico. 4. Idea constructiva, formulación y ejecución como proyecto de investigación. Búsqueda y elaboración de resultados que conforman los proyectos de la arquitectura y el diseño

Role of melatonin on embryo viability in sheep

Melatonin is a natural hormone synthesised in the pineal gland, the activity of which is regulated by day-night perception and dictates seasonal rhythms in reproduction in ovine species. Exogenous melatonin, administered via subcutaneous implants, is used to prolong the breeding season of ewes and can increase the proportion of pregnant ewes (fertility rate) and litter size. The increased proportion of ewes that become pregnant and the number of lambs born per lambing among melatonin-treated sheep may be caused by increased embryo survival, through enhanced luteal function, reduced antiluteolytic mechanisms, or improved embryo quality. This review focuses on the effects of melatonin on embryo viability and summarises the processes by which this hormone affects the ovary, follicle, oocyte, corpus luteum and embryo. Moreover, the effects of melatonin on the mechanisms of in vivo maternal recognition of pregnancy in sheep and the protective action that it appears to have on the in vitro procedures that are used to obtain healthy embryos are reviewed.Fil: Abecia, José Alfonso. Universidad de Zaragoza; EspañaFil: Forcada Miranda, Fernando. Universidad de Zaragoza; EspañaFil: Vazquez, Maria Isabel. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Muiño-Blanco,Teresa. Universidad de Zaragoza; EspañaFil: Cebrián-Pérez, José A.. Universidad de Zaragoza; EspañaFil: Pérez-Pe, Rosaura. Universidad de Zaragoza; EspañaFil: Casao, Adriana. Universidad de Zaragoza; Españ

Sperm quality and seminal plasma proteins in three sheep breeds under high altitude and tropical conditions

We tested the hypothesis that sheep breed can influence the sperm quality and seminal plasma (SP) composition and investigated any potential relationship between SP proteins and antioxidant enzyme activities (AO) with sperm quality. Ejaculates from twelve rams of three breeds were obtained during the rainy season at high altitudes, and sperm quality was automatically evaluated (CASA-Hamilton Thorne). The AO of superoxide dismutase, glutathione peroxide and glutathione reductase (GR) in SP was evaluated and total proteins were separated by SDS-PAGE. Comparative analyses of semen quality parameters between breeds revealed that Creole and Hampshire breeds had a higher sperm quality compared with Romney Marsh (p<0.05), although no difference in AO was found. GR activity was negatively correlated (p<0.05) with several kinematic variables and positively (p<0.05) with morphological abnormalities. The highest SP protein concentration was found in semen collected from Hampshire males compared with that from Creole and Romney Marsh (p<0.05). SDS-PAGE analysis showed the presence of 32 protein bands in SP with molecular weights between 334 and 10 kDa. Differences (p<0.05) between breeds in bands of 43, 25, 22 and 20 kDa were observed. These results evidence a relationship between the protective effect of the antioxidant enzyme system in SP of three ram types under high altitude and tropical conditions and semen quality. Our findings also suggest that the identified proteins might play an important role in sperm physiology and quality