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1.
Protoplasma ; 261(1): 15-29, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-37418157

RÉSUMÉ

Colleters are secretory structures characteristic of the apices of more than 60 botanical families. In the Myrtaceae, three types of colleters were previously described: petaloid, conical, and euriform. In Argentina, most species of the Myrtaceae family grow in subtropical regions and a few in the temperate-cold zones of Patagonia. We evaluated the vegetative buds of five species of the subfamily Myrtoideae, tribe Myrtea: Amomyrtus luma, Luma apiculata, and Myrceugenia exsucca, native to the temperate rainforests of Patagonia and Myrcianthes pungens and Eugenia moraviana from the riparian forest of northwestern Corrientes, in order to analyze the presence and morphological types and main secretion products of colleters. Optical and scanning electron microscopy was used to identify the presence of colleters in vegetative organs. Histochemical tests were performed to identify the main secretion products in these structures. The colleters are on the inner side of the leaf primordia and cataphylls and on the edge of the petiole, where they replace the stipules. They are classified as homogeneous because they consist of epidermis and internal parenchyma, both formed by cells with similar characteristics. They lack vascularization and originate from the protodermis. The colleters are of the conical type in L. apiculata, M. pungens, and E. moraviana and of the euriform type in A. luma and M. exsucca, the latter being identified by its dorsiventrally flattened shape. Histochemical tests showed the presence of lipids, mucilage, phenolic compounds, and proteins. This is the first time that colleters have been described in the analyzed species; the taxonomical and phylogenetic importance of this structures is discussed in relation to the Myrtaceae family.


Sujet(s)
Myrtaceae , Humains , Phylogenèse , Microscopie électronique à balayage , Feuilles de plante , Polyosides
2.
Reprod Fertil Dev ; 35(11): 563-574, 2023 Jul.
Article de Anglais | MEDLINE | ID: mdl-37290449

RÉSUMÉ

CONTEXT: Melatonin influences female reproduction, but expression of the melatonin system has not been characterised in the ovine uterus. AIMS: We aimed to determine whether synthesising enzymes (arylalkylamine N-acetyltransferase (AANAT) and N-acetylserotonin-O-methyltransferase (ASMT)), melatonin receptors 1 and 2 (MT1 and MT2), and catabolising enzymes (myeloperoxidase (MPO) and indoleamine 2,3-dioxygenase 1 and 2 (IDO1 and 2)), are expressed in the ovine uterus, and if they are influenced by the oestrous cycle (Experiment 1) or by undernutrition (Experiment 2). METHODS: In Experiment 1, gene and protein expression was determined in sheep endometrium samples collected on days 0 (oestrus), 5, 10 and 14 of the oestrous cycle. In Experiment 2, we studied uterine samples from ewes fed either 1.5 or 0.5times their maintenance requirements. KEY RESULTS: We have demonstrated the expression of AANAT and ASMT in the endometrium of sheep. AANAT and ASMT transcripts, and AANAT protein were more elevated at day 10, then decreased to day 14. A similar pattern was observed for MT2 , IDO1 , and MPO mRNA, which suggests that the endometrial melatonin system might be influenced by ovarian steroid hormones. Undernutrition increased AANAT mRNA expression, but seemed to decrease its protein expression, and increased MT2 and IDO2 transcripts, whereas ASMT expression was unaffected. CONCLUSIONS: The melatonin system is expressed in the ovine uterus and is affected by oestrous cycle and undernutrition. IMPLICATIONS: The results help explain the adverse effects of undernutrition on reproduction in sheep, and the success of exogenous melatonin treatments in improving reproductive outcomes.


Sujet(s)
Mélatonine , Animaux , Ovis/génétique , Femelle , Mélatonine/métabolisme , Utérus/métabolisme , Endomètre/métabolisme , ARN messager/métabolisme , Arylalkylamine N-Acetyltransferase/génétique , Arylalkylamine N-Acetyltransferase/métabolisme , Acetylserotonin O-Methyltransferase/génétique , Acetylserotonin O-Methyltransferase/métabolisme
3.
Theriogenology ; 198: 123-130, 2023 Mar 01.
Article de Anglais | MEDLINE | ID: mdl-36584633

RÉSUMÉ

Our aim was to investigate the oviduct environment by studying oviduct gene expression after undernutrition in day-5 pregnant ewes with different initial (i) BCS, and its association with the number of embryos recovered. Thirty-six ewes were divided into 2 groups with different iBCS: iBCS ≥2.75 (n = 19; high, H) and iBCS ≤2.25 (n = 17; low, L), and were randomly assigned to two nutritional treatments for 20 days: 1.5 (control, C) or 0.5 (underfed, U) times the daily maintenance requirements. Thus, the final four groups were: high-iBCS control (HC, n = 9), high-iBCS underfed (HU, n = 10), low-iBCS control (LC, n = 9) and low-iBCS underfed (LU, n = 8). Samples of oviduct were collected and the expression of target genes was quantified using real-time PCR. While high-iBCS control ewes presented more ADIPOR1 mRNA than the high-iBCS underfed group (P < 0.05) and low-iBCS control ewes (P = 0.01), high-iBCS underfed group presented higher ADIPOR2 gene expression than low-iBCS underfed ewes (P < 0.01) evidencing a differential oviductal gene expression for these receptors. In high-iBCS ewes, control animals presented higher IGFBP2 gene expression than underfed ewes (P < 0.05), associated these results with a poor oviductal environment. High-iBCS underfed ewes presented higher IGFBP4 gene expression than high-iBCS control ewes (P < 0.05). Stepwise regression models, using various combinations of data on metabolic and reproductive hormones, and oviduct gene expression as independent variables, identified a set of variables that accounted for 75% of the variation in the number of embryos recovered. In conclusion, the oviductal gene expression depends on body reserves and nutritional treatment, and the effect is gene-specific.


Sujet(s)
Malnutrition , Maladies des ovins , Grossesse , Femelle , Animaux , Ovis , Malnutrition/médecine vétérinaire , Oviductes , Trompes utérines , Expression des gènes , Phénomènes physiologiques nutritionnels chez l'animal
4.
Semergen ; 48(4): 245-251, 2022.
Article de Espagnol | MEDLINE | ID: mdl-35523661

RÉSUMÉ

Sexuality is a complex and multidimensional phenomenon that constitutes a fundamental component in human relationships. Pregnancy is a crucial period in women's life and the physiological changes that happen in this period affect their sexuality. OBJECTIVE: Knowing how pregnancy impacts on sexual behaviors in millenial generation compared to baby boom generation. MATERIAL AND METHODS: Descriptive and cross-sectional study, by means of a self-completed, population-based survey, to a sample of pregnant women in the third trimester of gestation who attended Primary Care. A descriptive study of the frequency distribution of all the variables was carried out. RESULTS: In baby boom generation and millennial generation, it is observed that during pregnancy couple's attraction decreases slightly. According to variables desire and frequency of intercourse, results obtained show that as the pregnancy progresses there is a marked decrease in desire and intercourse frequency. Women state that they do not have enough information about sexuality in their current state, despite years having passed. CONCLUSIONS: During last 35 years, sexual behaviors have not changed in pregnant women. In both generations, changes in desire and intercourse domains were particularly significant, being in third trimester of pregnancy when frequency of intercourse decline. Pregnant women continue to hold erroneous beliefs about sexuality and request more sexual education.


Sujet(s)
Femmes enceintes , Sexualité , Études transversales , Femelle , Humains , Croissance démographique , Grossesse , Femmes enceintes/psychologie
5.
SEMERGEN, Soc. Esp. Med. Rural Gen. (Ed. Impr.) ; 48(4): 245-251, mayo - jun. 2022. tab, graf
Article de Espagnol | IBECS | ID: ibc-205236

RÉSUMÉ

La sexualidad es un fenómeno complejo y multidimensional que constituye un componente fundamental en las relaciones humanas. El embarazo es un periodo crucial en la vida de las mujeres y los cambios fisiológicos que ocurren durante este periodo inciden en su sexualidad. Objetivo: Conocer qué impacto produce la gestación en las conductas sexuales en la generación millennial comparado con la generación baby boom. Material y métodos: Estudio descriptivo y transversal, mediante encuesta autocumplimentada, de base poblacional, a una muestra de mujeres embarazadas en el tercer trimestre de gestación que acudían a una consulta del equipo de atención primaria. Se realizó un estudio descriptivo de distribución de frecuencias de todas las variables. Resultados: Tanto en la generación baby boom como en la generación millennial se observa que durante el embarazo la atracción por la pareja disminuye ligeramente. En las variables deseo y frecuencia de coito los resultados obtenidos muestran que a medida que progresa el embarazo hay una disminución marcada del deseo y la frecuencia coital. Las mujeres manifiestan que no tienen suficiente información sobre la sexualidad en su estado actual, a pesar de los años transcurridos. Conclusión: Las conductas sexuales en las mujeres embarazadas no han cambiado en los últimos 35 años. Los cambios observados en ambas generaciones, en los dominios deseo y coito, fueron particularmente notables, siendo en el tercer trimestre de embarazo cuando más decae la frecuentación del coito. Las gestantes siguen manteniendo creencias erróneas acerca de la sexualidad y solicitan más educación sexual (AU)


Sexuality is a complex and multidimensional phenomenon that constitutes a fundamental component in human relationships. Pregnancy is a crucial period in women's life and the physiological changes that happen in this period affect their sexuality. Objective: Knowing how pregnancy impacts on sexual behaviors in millenial generation compared to baby boom generation. Material and methods: Descriptive and cross-sectional study, by means of a self-completed, population-based survey, to a sample of pregnant women in the third trimester of gestation who attended Primary Care. A descriptive study of the frequency distribution of all the variables was carried out. Results: In baby boom generation and millennial generation, it is observed that during pregnancy couple's attraction decreases slightly. According to variables desire and frequency of intercourse, results obtained show that as the pregnancy progresses there is a marked decrease in desire and intercourse frequency. Women state that they do not have enough information about sexuality in their current state, despite years having passed. Conclusions: During last 35 years, sexual behaviors have not changed in pregnant women. In both generations, changes in desire and intercourse domains were particularly significant, being in third trimester of pregnancy when frequency of intercourse decline. Pregnant women continue to hold erroneous beliefs about sexuality and request more sexual education (AU)


Sujet(s)
Humains , Femelle , Grossesse , Adulte , Femmes enceintes/psychologie , Comportement sexuel , Sexualité , Études transversales
7.
Rev. osteoporos. metab. miner. (Internet) ; 12(1): 14-19, ene.-mar. 2020. tab
Article de Espagnol | IBECS | ID: ibc-192305

RÉSUMÉ

OBJETIVO: El hiperparatiroidismo primario normocalcémico es una variedad menos conocida del hiperparatiroidismo primario clásico. Presentamos en este estudio sus manifestaciones clínicas y los datos relacionados con el metabolismo mineral óseo, tanto desde el punto de vista analítico como densitométrico, comparando los mismos con un grupo de pacientes afectos de hiperparatiroidismo primario clásico, con hipercalcemia. MATERIAL Y MÉTODOS: Estudio de casos y controles donde consideramos caso a pacientes afectos de hiperparatiroidismo primario normocalcémico (n=25) y control (n=25) a pacientes con hiperpartiroidismo primario con hipercalcemia (hiperparatiroidismo primario clásico). Se les efectuó una evaluación clínica completa con recogida de datos clínicos y realizándose determinaciones analíticas en sangre y orina de 24h, así como la estimación de la densidad mineral ósea y el trabecular bone score por densitometría (absorciometría radiológica dual, DXA) y los parámetros ultrasonográficos en el calcáneo. RESULTADOS: En el estudio clínico, los pacientes afectos de hiperparatiroidismo primario clásico solo muestran una mayor prevalencia de urolitiasis (OR: 9,333; IC 95%: 1,50-82,7) en comparación con los pacientes que sufren un hiperparatiroidismo primario normocalcémico. En todos los demás parámetros clínicos, analíticos, densitométricos y ultrasonográficos, no se aprecian diferencias estadísticamente significativas entre ambos grupos. CONCLUSIONES: Con la excepción de los niveles séricos de calcio y la prevalencia de urolitiasis, el hiperparatiroidismo normocalcémico cursa de manera indistinguible del hiperparatiroidismo clásico


OBJECTIVE: Normocalcemic primary hyperparathyroidism is a less known variety of classical primary hyperparathyroidism. In this paper, we present its clinical expression and data related to bone mineral metabolism, both analytically and densitometrically, comparing them with a group of patients with classic primary hyperparathyroidism, with hypercalcemia. MATERIAL AND METHODS: Study of cases and controls where we consider case of patients with normocalcemic primary hyperparathyroidism (n=25) and control (n=25) of patients with primary hyperpartyroidism with hypercalcemia (classical primary hyperparathyroidism). A complete clinical assessment was carried out with clinical data collection and24h blood and urine analytical determinations were performed, as well as estimating bone mineral density and trabecular bone score by densitometry (dual x‐ray absorptiometry, DXA) and ultrasound parameters in the calcaneus. RESULTS: In this clinical study, patients with classic primary hyperparathyroidism only show a higher prevalence of urolithiasis (OR: 9.333; 95% CI: 1.50‐82.7) compared to patients suffering from a normocalcemic primary hyperparathy‐roidism. In all other clinical, analytical, densitometric and ultrasonographic parameters, there are no statistically significant differences between the two groups. CONCLUSIONS: Apart from serum calcium levels and the prevalence of urolithiasis, normocalcemic hyperparathyroidism is indistinguishable from classical hyperparathyroidism


Sujet(s)
Humains , Mâle , Femelle , Adulte d'âge moyen , Sujet âgé , Densité osseuse/physiologie , Hyperparathyroïdie primitive/métabolisme , Hyperparathyroïdie primitive/physiopathologie , Hypercalcémie/physiopathologie , Calcanéus/imagerie diagnostique , Calcanéus/métabolisme , Os spongieux/imagerie diagnostique , Os spongieux/métabolisme , Études cas-témoins , Densitométrie
8.
Theriogenology ; 135: 189-197, 2019 Sep 01.
Article de Anglais | MEDLINE | ID: mdl-31226609

RÉSUMÉ

The aim of this study was to characterize insulin, leptin and IGF-1 profiles after undernutrition in pregnant ewes with different initial body condition (iBCS) and to investigate embryo quality, uterine gene expression and presence and location of proteins during early gestation (day 5). Thirty-six Rasa Aragonesa ewes were divided into 2 groups with different BCS: BCS> 2.75 (high, H, n = 19) and BCS <2.25 (low, L, n = 17) and they were randomly assigned to two nutritional treatments: 1.5 maintenance (M) (control, C) or 0.5 (M) (undernourishment, U) times the daily maintenance requirements establishing four groups: high-iBCS control (HC, n = 9), high-iBCS undernourished (HU, n = 10), low-iBCS control (LC, n = 9) and low-iBCS undernourished (LU, n = 8). High-iBCS ewes presented higher concentration of IGF-1, reflecting a better metabolic status in these animals. There was a greater proportion of high-iBCS ewes presenting more than one CL (P < 0.05), and associated greater P4 plasma concentration, number of recovered embryo and a tendency for higher embryo viability rate (P = 0.13). In uterus, undernourished ewes tended to present lower P4 (P = 0.09) and higher E2 concentration (P = 0.10). Inmunostaining of uterine progesterone and estrogen receptors (PR and ERα) was not affected by iBCS and nutritional treatment. Ewes with low-iBCS tended to have more INSR mRNA, and undernourished ewes tended to have more IGFBP2 mRNA expression (P < 0.08). An interesting finding was that the uterine response to undernutrition was dependent on iBCS: a higher expression of GHR (P < 0.05) and a tendency in IGFBP5 (P = 0.09) mRNA was found in undernourished than control ewes but only in the high-iBCS group. In summary, the present study demonstrates that the endocrine response and the uterine gene expression to undernutrition depend on the initial body energy reserves (iBCS) and appears to be associated with a differential embryo quality.


Sujet(s)
Privation alimentaire , Gestation animale , Ovis/physiologie , Utérus/physiologie , Animaux , Composition corporelle , Femelle , Grossesse
9.
Rev. esp. drogodepend ; 44(2): 26-42, abr.-jun. 2019. tab
Article de Espagnol | IBECS | ID: ibc-184428

RÉSUMÉ

Las nuevas tecnologías de la información y la comunicación (TIC) han cambiado el mundo. Sabemos de sus ventajas: velocidad, accesibilidad, superación de barreras, intercomunicación en tiempo real en cualquier lugar, entre otras. Sin embargo, este avance tecnológico también tiene sus peligros: el mal uso, la posible adicción, riesgo de prácticas como el cy-berbullying, el grooming, suplantación de identidad, entre otros. Prácticas que en vez de potenciar al ser humano lo puede incluso destruir. En este trabajo se presentan los principales resultados de un estudio descriptivo sobre uso que hacen de las TICs, jóvenes residentes en la Comunidad Canaria. Para ello fueron entrevistados un total de 6134 jóvenes (entre 12 y 17 años) afincados en las 7 islas del archipiélago. Se exponen resultados (porcentajes y Chi cuadrado) sobre el uso de internet, teléfono móvil, videojuegos y apuestas en línea de la muestra estudiada. Estos resultados pretenden contribuir a describir los patrones de uso de las TIC en población juvenil, así como a establecer los límites entre el uso y el mal uso de estas tecnologías


New information and communication technologies (ICT) have changed the world. Their advantages are well known: speed, accessibility, overcoming barriers, intercommunication in real time anywhere, etc. These technological advances nevertheless also have their dangers: misuse, possible addiction, risks such as cyberbullying, grooming, identity impersonation, etc., Instead of empowering the human being, these practices can even destroy him. The present work is a descriptive study of the use of ICT (Information and communication technology) by young people living in the Canary Islands. A total of 6134 teenagers (from 12 to 17 years old) settled on the seven islands of the archipelago were interviewed. Results (percentages and Chi square) are presented on the use of the Internet, mobile phone, videogames and online bets. These results are intended to help to clarify the boundaries between the use and abuse of these technologies


Sujet(s)
Humains , Mâle , Femelle , Enfant , Adolescent , Jeux vidéo/statistiques et données numériques , Accès à Internet/statistiques et données numériques , Réseautage social en ligne , Comportement de l'adolescent , Entretiens comme sujet , Espagne/épidémiologie
11.
Cir. parag ; 40(1): 13-17, mayo. 2016. ilus
Article de Espagnol | LILACS, BDNPAR | ID: biblio-972585

RÉSUMÉ

Introducción: La reparación de la pared abdominal, presenta escenarios complejos, como los abdómenes abiertos con ostomías o fístulas intestinales, que para su tratamiento el cirujano debe buscar la táctica quirúrgica y el manejo ideal para cada caso. Objetivo: Describir los resultados en la reparación de defectos complejos de la pared abdominal y restitución de tránsito intestinal en un solo tiempo. Pacientes y método: Estudio observacional, descriptivo, prospectivo y longitudinal, de una serie de casos de 30 pacientes, ambos sexos, mayores a 18 años, portadores de defectos complejos de la pared abdominal (abdomen abierto cicatrizado por segunda intención y hernias paraestomales) y ostomías que ingresaron para cirugía electiva en la II Cátedra de Clínica Quirúrgica del Hospital de Clínicas de marzo del 2011 a diciembre del 2015. Todos los pacientes fueron evaluados con tomografía axial computarizada, según el caso sometidos a preparación con neumoperitoneo progresivo pre operatorio y manejados por equipo multidisciplinario...


Introduction: Abdominal wall repair, presents complex scenarios, as the bellies open with ostomy or intestinal fistulas, that treatment the surgeon should seek surgical tactics and ideal management for each case. Objective: To describe the results in repair of complex defects of the abdominal wall and return of intestinal transit in a single time. Patients and methods: observational, descriptive, prospective and longitudinal study, a series of 30 patients, both sexes, over 18 years, carriers of complex defects of the abdominal wall (open abdomen healed by second intention and paraestomales herniations) and ostomy admitted for elective surgery at the surgical clinic of the Hospital de Clínicas of March 2011 to2015 December II. All patients were evaluated with axial computed tomography, according to the case subject to progressive pneumoperitoneumprogressive pre operative and managed by a multidisciplinary team...


Sujet(s)
Mâle , Femelle , Humains , Adulte , Adulte d'âge moyen , Sujet âgé , Sujet âgé de 80 ans ou plus , Paroi abdominale/chirurgie , Intestins/chirurgie
12.
J Anim Physiol Anim Nutr (Berl) ; 100(2): 236-42, 2016 Apr.
Article de Anglais | MEDLINE | ID: mdl-26122561

RÉSUMÉ

Many species show diet-induced flexibility of activity of intestinal enzymes; however, molecular and genetic mechanisms responsible for such modulation are less known, particularly in altricial birds. The goal of our study was to test whether a diet-induced increase in activity of intestinal maltase and sucrase in house sparrow nestlings is matched with an increase in maltase-glucoamylase (MG) and sucrase-isomaltase (SI) complex mRNAs respectively. Both enzyme activities were significantly higher in mid-intestine of nestlings fed a medium-starch (MS) diet compared to those fed a starch-free (SF) diet. In contrast to the similar pattern of dietary induction for both enzyme activities, diet MS elevated significantly only the level of MG mRNA, but not SI mRNA. The coordinated increase in activity of maltase and in MG mRNA is consistent with the hypothesis that dietary induction of this enzyme is under transcriptional control. In contrast, the lack of such coordination for changes in activity of sucrase and SI mRNA suggests that upregulation of this enzyme may be achieved by post-translational factor(s). We conclude that genetic mechanisms responsible for diet-induced flexibility of digestive enzymes in birds may differ from that observed in mammals.


Sujet(s)
Régulation de l'expression des gènes au cours du développement/physiologie , Régulation de l'expression des gènes codant pour des enzymes/physiologie , Glycosidases/métabolisme , Intestins/enzymologie , Moineaux/métabolisme , Transcription génétique/physiologie , Vieillissement , Animaux , Glycosidases/génétique , ARN messager/génétique , ARN messager/métabolisme , Moineaux/croissance et développement , Invertase/métabolisme , alpha-Glucosidase/métabolisme
13.
Psicol. conduct ; 23(1): 25-34, ene.-abr. 2015. tab
Article de Espagnol | IBECS | ID: ibc-139094

RÉSUMÉ

Las relaciones de pareja y las habilidades sociales están estrechamente relacionadas. Los componentes del amor (intimidad, deseo y compromiso) presentan aspectos nucleares en el ámbito de las relaciones interpersonales. Y un aspecto clave en las relaciones de pareja y en el ámbito de las habilidades sociales es el respeto interpersonal, la capacidad de armonizar los derechos propios con los de la otra persona. El respeto está relacionado con los estilos de respuesta sumiso, dominante, pasivo-agresivo y equilibrado. En este estudio se han comparado tres grupos de personas (con tendencia a la sumisión, a la dominancia y personas equilibradas) para comprobar la percepción que tienen de su relación de pareja. Los resultados indican que las personas sumisas y dominantes valoran de forma más negativa su relación (y a su pareja) que las personas equilibradas


Couple relationships and social skills are closely related. Love components (intimacy, desire and commitment) have nuclear issues in the area of interpersonal relationships. A key aspect in relationships and in the social skills area is Interpersonal Respect, the ability to harmonize personal rights with the other’s rights. Respect is related with submissive, dominant, passive-aggressive and fair response styles. This study compared three groups of people (one with a tendency to submission, a second with a tendency to dominance, and a third of balanced people) to check perceptions of couple relationship. The results indicate that submissive and dominant people attach a more negative value to their relationship (and their partners) than balanced people


Sujet(s)
Adulte , Femelle , Humains , Mâle , Relations interpersonnelles , Compétences sociales , Thérapie de couple , Surveillance épidémiologique/tendances , Affirmation de soi , Empathie , Communication , Amour , Attachement à l'objet , Domination-subordination , Conflit psychologique , Espagne/épidémiologie
14.
Mol Hum Reprod ; 21(3): 244-54, 2015 Mar.
Article de Anglais | MEDLINE | ID: mdl-25452326

RÉSUMÉ

The acrosome reaction is a unique event in the lifespan of sperm characterized by the exocytosis of the acrosomal content and the release of hybrid vesicles formed by patches of the outer acrosomal membrane and the plasma membrane. This unique regulated exocytosis is mediated by essentially the same membrane fusion machinery present in neuroendocrine cells. However, whereas secretion in neuroendocrine cells occurs in less than a second, the acrosome reaction is normally assessed after several minutes of incubation with inducers. In this report, we measured the kinetics of human sperm exocytosis triggered by two stimuli (calcium ionophore and progesterone) by using electron microscopy and three different approaches based on the incorporation of fluorescent Pisum sativum agglutinin into the acrosome upon opening of fusion pores connecting the extracellular medium with the acrosomal lumen. The results with the different methods are consistent with a slow kinetics (t½ = 14 min). We also manipulated the system to measure different steps of the process. We observed that cytosolic calcium increased with a relatively fast kinetics (t½ = 0.1 min). In contrast, the swelling of the acrosomal granule that precedes exocytosis was a slow process (t½ = 13 min). When swelling was completed, the fusion pore opening was fast (t½ = 0.2 min). The results indicate that acrosomal swelling is the slowest step and it determines the kinetics of the acrosome reaction. After the swelling is completed, the efflux of calcium from intracellular stores triggers fusion pores opening and the release of hybrid vesicles in seconds.


Sujet(s)
Réaction acrosomique/physiologie , Acrosome/métabolisme , Membrane cellulaire/métabolisme , Exocytose/physiologie , Acrosome/effets des médicaments et des substances chimiques , Acrosome/ultrastructure , Réaction acrosomique/effets des médicaments et des substances chimiques , Adulte , A-23187/pharmacologie , Calcium/métabolisme , Ionophores calciques/pharmacologie , Membrane cellulaire/effets des médicaments et des substances chimiques , Membrane cellulaire/ultrastructure , Granulations cytoplasmiques/effets des médicaments et des substances chimiques , Granulations cytoplasmiques/métabolisme , Granulations cytoplasmiques/ultrastructure , Exocytose/effets des médicaments et des substances chimiques , Humains , Transport des ions/effets des médicaments et des substances chimiques , Cinétique , Mâle , Fusion membranaire/effets des médicaments et des substances chimiques , Microscopie électronique , Lectines végétales/pharmacologie , Progestérone/pharmacologie , Facteurs temps
15.
J Anim Physiol Anim Nutr (Berl) ; 99(4): 710-8, 2015 Aug.
Article de Anglais | MEDLINE | ID: mdl-25319346

RÉSUMÉ

This study investigated whether a 22-day period of undernutrition (half maintenance) could affect maternal endocrine responses and liver gene expression during early pregnancy (day 7). Thirty-five ewes were fed 1.5 (n = 15) or 0.5 (n = 20) their maintenance requirements and slaughtered on day 7 of the oestrus cycle or pregnancy (oestrus = day 0). Insulin, IGF, leptin and non-esterified fatty acids (NEFA) were determined on days -14, 0 and 7. Transcripts of the IGF family and adipokines receptors were determined in the liver by real-time RT-PCR. Underfed animals presented lower body weight and body condition, greater plasma concentration of NEFA, and lower plasma concentrations of leptin, insulin and IGF1 compared to adequately fed animals. Underfed ewes presented greater hepatic expression of IGFBP2 than well-fed ewes, but tended to have lesser expression of IGFBP5. While no effect of undernutrition on IGFBP4 and ADIPOR2 mRNA expressions was observed, they were increased by pregnancy in underfed animals. This study shows that undernutrition modifies endocrine profiles and hepatic gene expression of IGFBP2 and 5. The pregnancy status increased hepatic gene expression of IGFBP4 and ADIPOR2 mRNA in undernourished ewes.


Sujet(s)
Privation alimentaire , Régulation de l'expression des gènes/physiologie , Foie/métabolisme , Ovis/métabolisme , Aliment pour animaux , Phénomènes physiologiques nutritionnels chez l'animal , Animaux , Régime alimentaire/médecine vétérinaire , Cycle oestral , Acide gras libre/sang , Femelle , Insuline/sang , Facteur de croissance IGF-I/métabolisme , Leptine/sang , Données de séquences moléculaires , Grossesse , ARN messager , Ovis/sang
16.
Zygote ; 23(1): 116-24, 2015 Feb.
Article de Anglais | MEDLINE | ID: mdl-24103562

RÉSUMÉ

To determine the effect of undernutrition on embryo production and quality in superovulated sheep, 45 ewes were allocated into two groups to be fed diets that provided 1.5 (control, C; n = 20) or 0.5 (low nutrition, L; n = 25) times daily requirements for maintenance, from oestrous synchronization with intravaginal sponges to embryo collection. Embryos were collected 7 days after the onset of oestrus (day 0). Low nutrition resulted in lower live weight and body condition at embryo collection (P < 0.05). Diet (P < 0.01) and day of sampling (P < 0.001) significantly affected plasma non-esterified fatty acid (NEFA) and insulin concentrations. Plasma leptin concentrations decreased on day 7 only in L ewes. A significant effect of dietary treatment (P < 0.05) and day (P < 0.0001) was observed on plasma insulin-like growth factor (IGF)-I concentrations. The number of recovered oocytes and embryos did not differ between the groups (L: 15.4 ± 0.4; C: 12.4 ± 0.4). Recovery rate was lower (P < 0.05) in the L (60%) than in the C group (73%). The total number of embryos and number of viable-transferable embryos (5.0 ± 0.3 and 3.4 ± 0.3 embryos, respectively) of the L group were lower (P < 0.1) when compared with controls (8.4 ± 0.4 and 6.2 ± 0.4 embryos, respectively). Undernutrition during the period of superovulation and early embryonic development reduced total and viable number of embryos. These effects might be mediated by disruption of endocrine homeostasis, oviduct environment and/or oocyte quality.


Sujet(s)
Embryon de mammifère/physiologie , Malnutrition/complications , Phénomènes physiologiques nutritionnels maternels , Superovulation , Phénomènes physiologiques nutritionnels chez l'animal , Animaux , Régime alimentaire , Acide gras libre/sang , Femelle , Insuline/sang , Facteur de croissance IGF-I/analyse , Prélèvement d'ovocytes , Progestérone/sang , Ovis aries
17.
J Anim Physiol Anim Nutr (Berl) ; 99(3): 501-10, 2015 Jun.
Article de Anglais | MEDLINE | ID: mdl-24954670

RÉSUMÉ

Maternal periconceptional undernutrition is associated with altered development and increased risks of adverse outcomes in the offspring. The aim of this work was to determine the effect of periconceptional undernutrition on behavioural and reproductive aspects of the offspring. Fifty ewes were synchronized in oestrus (day 0) and allocated to two groups (n = 25) to be fed diets that provided 1.5 (C) or 0.5 (L) times the requirements for maintenance until day 15. Ewes were mated and fed the control diet from day 16 until lambing. Two months after lambing, 26 lambs were exposed to tests to determine their cognitive/emotional responses. Six ewe lambs were euthanized and in vitro oocyte maturation and fertilization procedures performed. The experimental diets produced no changes of mean live weight (LW) of C ewes, L ewes presenting a reduction in their initial LW with significant differences at day 15, in comparison with C ewes (p < 0.05). L ewes experienced a significant reduction in their body condition (BC) in comparison with C ewes (p < 0.05). Fourteen days after the onset of the experimental diets, mean LW and BC of L ewes was significantly lower than those of C ewes (p < 0.05). Undernourished ewes presented a trend to a reduction of prolificacy and fecundity (p < 0.10) in comparison with C ewes. Emotional and cognitive test revealed a similar response between groups. Ewe lambs from the undernourished ewes presented a population of oocytes 1.7 times higher than ovaries from control ewe lambs (66.0 ± 0.73 vs. 113.7 ± 15.6 oocytes; p < 0.05) and had more oocytes in the 'good' (p < 0.05) and 'healthy' (p < 0.05) categories. In conclusion, a low plane of nutrition around conception significantly increases quantity and quality of the oocyte population of 60-day-old female descendants. Modifications of the cognitive and emotional responses of the progeny have not been evidenced.


Sujet(s)
Cognition , Émotions , Malnutrition/médecine vétérinaire , Ovocytes/physiologie , Phénomènes physiologiques nutritionnels prénatals , Ovis/croissance et développement , Phénomènes physiologiques nutritionnels chez l'animal , Animaux , Comportement animal/physiologie , Poids , Femelle , Fécondation in vitro , Techniques de maturation in vitro des ovocytes/médecine vétérinaire , Grossesse , Effets différés de l'exposition prénatale à des facteurs de risque
18.
J Dev Orig Health Dis ; 5(2): 79-87, 2014 Apr.
Article de Anglais | MEDLINE | ID: mdl-24847694

RÉSUMÉ

Maternal periconceptional undernutrition is associated with altered development and increased risks of adverse outcomes in the offspring. This circumstance is normal in flocks under extensive farming systems, which depend on natural forage resources. The aim of this study was to determine the effect of periconceptional undernutrition in sheep on behavioral and reproductive aspects of the offspring. Eighty ewes were synchronized in estrus and allocated to two groups (n=40) to be fed diets that provided 1.5 (C) or 0.5 (L) times the requirements for maintenance. Ewes were mated and 7 days later fed the control diet until lambing. One month after lambing, 32 lambs were exposed to tests to determine their cognitive and emotional responses. Six ewe lambs were euthanized and in vitro maturation and fertilization procedures were performed. L ewes presented a significant reduction in prolificacy and fecundity (P<0.05) in comparison with C ewes. Mean LW at lambing of L lambs was significantly higher than C lambs (C: 3.80 ± 0.11; L: 4.24 ± 0.15 kg, P<0.05). Lambs born from C ewes spent more time walking than L lambs (P<0.05) in the isolation test, revealing a decrease in the locomotor activity of lambs born from undernourished ewes around conception. Ewe lambs from the undernourished ewes presented a total population of oocytes 2.3 times higher than ovaries from control ewe lambs (60.0 ± 7.8 v. 140.0 ± 18.5 oocytes; P<0.05). In conclusion, periconceptional undernutrition is able to produce an increment in the body weight and the oocyte population, and an alteration of the locomotor activity of the offspring.


Sujet(s)
Phénomènes physiologiques nutritionnels chez l'animal , Malnutrition/médecine vétérinaire , Ovocytes/croissance et développement , Effets différés de l'exposition prénatale à des facteurs de risque , Phénomènes physiologiques nutritionnels prénatals , Ovis/physiologie , Animaux , Poids , Cognition , Femelle , Fécondation in vitro/médecine vétérinaire , Techniques de maturation in vitro des ovocytes/médecine vétérinaire , Ovocytes/cytologie , Grossesse , Ovis/embryologie , Ovis/croissance et développement
19.
Anim Reprod Sci ; 141(1-2): 52-61, 2013 Sep.
Article de Anglais | MEDLINE | ID: mdl-23948208

RÉSUMÉ

The effect of exogenous melatonin on embryo viability in undernourished ewes was investigated. At lambing, 24 ewes were treated (+MEL) or not (-MEL) with a melatonin implant. After 45 days, both groups were fed to provide 1.5 (Control, C) or 0.5 (Low, L) times daily maintenance requirements, so that experimental groups were: C-MEL, C+MEL, L-MEL and L+MEL. Ewes were mated (Day 0) and on Day 5 embryos were recovered and classified according to their developmental stage and morphology. Ovaries were used for in vitro fertilization and uterine horns were processed to study progesterone and oestrogen receptor (PR and ERα) expression by inmunohistochemistry. After 21 days, groups L-MEL and L+MEL had an average weight loss of 10kg (P<0.001). Number of viable embryos per CL from L+MEL (0.50±0.2) was higher than from other groups (P<0.05). Overall, the melatonin effect was particularly evident in undernourished ewes, increasing both viability (L+MEL: 65%; L-MEL: 25%; P<0.05) and pregnancy rates (L+MEL: 66.6%; L-MEL: 16.6%; P<0.05). Neither nutrition and melatonin nor their interaction had a significant effect on the in vitro oocyte development. Melatonin treatment tended to increase the percentage of positive cells to PR in deep glandular epithelium, independently of diet (P=0.09), and the greatest staining intensity of PR was observed in the luminal and superficial glandular epithelia (P<0.0001). In conclusion, melatonin implants at lambing during the breeding season improve the viability of embryos recovered from undernourished ewes, although this effect seems not to be mediated at the oocyte competence level.


Sujet(s)
Embryon de mammifère/effets des médicaments et des substances chimiques , Malnutrition/médecine vétérinaire , Phénomènes physiologiques nutritionnels maternels/effets des médicaments et des substances chimiques , Mélatonine/pharmacologie , Ovis/physiologie , Utérus/physiologie , Aliment pour animaux/analyse , Animaux , Régime alimentaire/médecine vétérinaire , Endomètre/métabolisme , Femelle , Grossesse , Récepteurs des oestrogènes/génétique , Récepteurs des oestrogènes/métabolisme , Récepteurs à la progestérone/génétique , Récepteurs à la progestérone/métabolisme
20.
Am J Phys Anthropol ; 151(1): 102-9, 2013 May.
Article de Anglais | MEDLINE | ID: mdl-23595645

RÉSUMÉ

Ancient molecular typing depends on DNA survival in archaeological bones. Finding valuable tools to predict DNA presence in ancient samples, which can be measured prior to undertaking a genetic study, has become an important issue as a consequence of the peculiarities of archaeological samples. Since the survival of DNA is explained by complex interrelations of multiple variables, the aim of the present study was to analyze morphological, structural, chemical, and biological aspects of a set of medieval human bones, to provide an accurate reflection of the state of preservation of the bony components and to relate it with DNA presence. Archaeological bones that yielded amplifiable DNA presented high collagen content (generally more than 12%), low racemization values of aspartic acid (lesser than 0.08), leucine and glutamic acid, low infrared splitting factor, small size of crystallite, and more compact appearance of bone in the scanning electron micrographs. Whether these patterns are characteristic of ancient bones or specific of each burial site or specimen requires further investigation.


Sujet(s)
Os et tissu osseux/composition chimique , ADN/analyse , Typage moléculaire/méthodes , Paléontologie/méthodes , Acide aspartique/analyse , Acide aspartique/composition chimique , Collagène/analyse , Collagène/composition chimique , ADN/composition chimique , Durapatite/analyse , Durapatite/composition chimique , Histoire médiévale , Humains , Isomérie , Microscopie électronique à balayage , Espagne
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