81 research outputs found
Efecto de progesterona y estradiol en los procesos de capacitación y apoptosis del espermatozoide ovino
Tras la cópula, los espermatozoides pasan a un medio, primero al fluido uterino y posteriormente al fluido oviductal, donde entran en contacto con las hormonas predominantes en la hembra: los estrógenos y la progesterona, cuyos efectos sobre el espermatozoide ovino todavía no están muy estudiados. En este trabajo se han evaluado el efecto in vitro de dos dosis (alta y baja) de progesterona (P4, 10 ng/mL y 100 pg/mL) y de 17β-estradiol (E2, 1 ng/mL y 10 pg/mL) sobre la calidad del espermatozoide ovino. Las técnicas laboratoriales utilizadas han sido el análisis de motilidad espermática mediante un sistema de análisis computerizado (CASA), viabilidad o integridad de membrana mediante la doble tinción de diacetato de carboxifluoresceína/ioduro de propidio, la capacitación espermática mediante la tinción con clorotetraciclina (CTC) y los procesos de apoptosis (inversión de fosfatidilserina) mediante la tinción con anexina V. No se observaron diferencias significativas en motilidad, viabilidad ni tinción con anexina V, aunque las muestras incubadas con concentraciones altas de E2 presentaron peores valores que el resto de los grupos de estudio. Sin embargo, en las muestras incubadas con concentraciones altas de P4 el porcentaje de espermatozoides capacitados aumentó significativamente (P<0,05) con respecto a la muestra control. Estos resultados indican que la incubación con una concentración elevada de P4 (10 ng/mL) estimula el proceso de capacitación de los espermatozoides, sin afectar al resto de parámetros de calidad seminal, mientras que la incubación con estrógenos a concentraciones elevadas (1ng/mL) parece afectar negativamente a la calidad espermática. Palabras clave: 17β-estradiol, Progesterona, Espermatozoides, Capacitación, Apoptosis
Does melatonin exert its effect on ram sperm capacitation through nitric oxide synthase regulation?
Nitric oxide (NO·), synthesized from L-arginine by nitric oxide synthase (NOS), is involved in sperm functionality. NOS isoforms have been detected in spermatozoa from different species, and an increment in NOS activity during capacitation has been reported. This work aims to determine the presence and localization of NOS isoforms in ram spermatozoa and analyse their possible changes during in vitro capacitation. Likewise, we investigated the effect of melatonin on the expression and localization of NOS and NO· levels in capacitated ram spermatozoa. Western blot analysis revealed protein bands associated with neuronal NOS (nNOS) and epithelial NOS (eNOS) but not with inducible NOS (iNOS). However, the three isoforms were detected by indirect immunofluorescence (IFI), and their immunotypes varied over in vitro capacitation with cAMP-elevating agents. NO· levels (evaluated by DAF-2-DA/PI staining) increased after in vitro capacitation, and the presence of L-arginine in the capacitating medium raised NO· production and enhanced the acrosome reaction. Incubation in capacitating conditions with a high-cAMP medium with melatonin modified the NOS distribution evaluated by IFI, but no differences in Western blotting were observed. Melatonin did not alter NO· levels in capacitating conditions, so we could infer that its role in ram sperm capacitation would not be mediated through NO· metabolism
Cochlear implant in far advanced otosclerosis. Performance complications-long term results
Patients with far advanced otosclerosis demonstrated good performance with CI in 26/32 cases. In the cases with otosclerosis type 3, 5/6 patients had more difficulty in the insertion of electrodes, 1 of them with 2 electrodes within the IAC and leakage of LCR, and 5 of these recipients with tinnitus and poorer auditory outcome, with greater number of calibrations and adjustments inlevels T and C. Only two patient, 2/32 had FNS and were in otosclerosis type 3 with straight electrodes. None with perimodiolars electrodes.https://www.medigraphic.com/pdfs/audiologia/fon-2013/fon131b.pdfFil: Curet, Carlos Augusto. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Unidad Hospitalaria San Roque. Cátedra II de Otorrinolaringología; Argentina.Fil: Curet, Carlos Augusto. Centro Odontológico de Clínica Privada Curet SRL; Argentina.Fil: Curet, Carlos Augusto. Centro de Garganta, Nariz y Oído Dr. Hector Ruiz; Argentina.Fil: Ruíz, Héctor. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas; Argentina.Fil: Salvadores, María Inés. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Unidad Hospitalaria San Roque. Cátedra II de Otorrinolaringología ; Argentina.Fil: Salvadores, María Inés. Centro Odontológico de Clínica Privada Curet SRL; Argentina.Fil: Romani, Claudia. Centro Odontológico de Clínica Privada Curet SRL; Argentina.Fil: Dotto, Gabriela. Centro de Garganta, Nariz y Oído Dr. Hector Ruiz; Argentina.Fil: Queirolo, Adriana. Centro de Garganta, Nariz y Oído Dr. Hector Ruiz; Argentina.Fil: Fil: Chailé, Iván David. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas; Argentina.Fil: Chailé, Iván David. Centro Odontológico de Clínica Privada Curet SRL; Argentina.Fil: Robledo, Hugo. Centro Odontológico de Clínica Privada Curet SRL; Argentina.Fil: Muiño, Juan Carlos. Centro Odontológico de Clínica Privada Curet SRL; Argentina.Otorrinolaringologí
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
Identification of ß-nerve growth factor in dromedary camel seminal plasma and its role in induction of ovulation in females
The main objective of this study was to demonstrate the effect of seminal plasma ovulation inducing factor (OIF) on ovulation in female camels. Seminal plasma was fractionated using gel filtration chromatography, and two protein peaks were obtained and analysed by western blotting. The effect of the bioactive protein fraction (OIF/ß-NGF) was tested by intramuscular injection (1 ml) in synchronized females with the following treatments: PBS (negative control group, n=3); 20 /jg Buserelin (GnRH analogue, positive control group; n=3); and purified OIF with doses of 1 and 2 mg (n = 5, each treatment). Blood samples were collected every two days from day 0 until 14 days post-treatment, and the progesterone concentration was assessed. The obtained results showed that the OIF is highly present in the seminal plasma of dromedary camels as a protein with a molecular mass of approximately 14 kDa. It was detected as a betaNerve Growth Factor, named Cam-ß-NGF. The effect of this molecule on ovulation was clearly demonstrated by the significant increase of the plasma progesterone concentration in the treated female groups (1 and 2 mg of Cam-ß-NGF) as observed in Buserelin group. In summary, intramuscular injection of ß-NGF isolated from dromedary camel seminal plasma induces ovulation in females with similar rate to Buserelin treatment
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
Prevalence of smoking and incidence of initiation in the Latin American adult population: the PLATINO study
Background: the PLATINO project was launched in 2002 in order to study the prevalence of chronic obstructive pulmonary disease (COPD) in Latin America. Because smoking is the main risk factor for COPD, detailed data on it were obtained. the aim of this paper was to evaluate the prevalence of smoking and incidence of initiation among middle-aged and older adults (40 years or older). Special emphasis was given to the association between smoking and schooling.Methods: PLATINO is a multicenter study comprising five cross-sectional population-based surveys of approximately 1,000 individuals per site in São Paulo (Brazil), Santiago (Chile), Mexico City (Mexico), Montevideo (Uruguay) and Caracas (Venezuela). the outcome variable was smoking status (never, former or current). Current smokers were those who reported to smoke within the previous 30 days. Former smokers were those who reported to quit smoking more than 30 days before the survey. Using information on year of birth and age of smoking onset and quitting, a retrospective cohort analysis was carried out. Smoking prevalence at each period was defined as the number of subjects who started to smoke during the period plus those who were already smokers at the beginning of the period, divided by the total number of subjects. Incidence of smoking initiation was calculated as the number of subjects who started to smoke during the period divided by the number of non-smokers at its beginning. the independent variables included were sex, age and schooling.Results: Non-response rates ranged from 11.1% to 26.8%. the prevalence of smoking ranged from 23.9% (95% CI 21.3; 26.6) in São Paulo to 38.5% (95% CI 35.7; 41.2) in Santiago. Males and middle-aged adults were more likely to smoke in all sites. After adjustment for age, schooling was not associated with smoking. Using retrospective cohort analysis, it was possible to detect that the highest prevalence of smoking is found between 20-29 years, while the highest incidence is found between 10-19 years. Age of smoking onset tended to decline over time among females.Conclusion: the prevalence of smoking varied considerably across sites, but was lower among countries with national anti-smoking campaigns.Univ Fed Pelotas, Pelotas, BrazilUniv Republica, Montevideo, UruguayInst Nacl Enfermedades Resp, Mexico City, DF, MexicoUniversidade Federal de São Paulo, São Paulo, BrazilPontificia Univ Catolica Chile, Santiago, ChileCent Univ Venezuela, Caracas, VenezuelaUniversidade Federal de São Paulo, São Paulo, BrazilWeb of Scienc
Surface indicators are correlated with soil multifunctionality in global drylands
Multiple ecosystem functions need to be considered simultaneously to manage and protect the several ecosystem services that are essential to people and their environments. Despite this, cost effective, tangible, relatively simple and globally relevant methodologies to monitor in situ soil multifunctionality, that is, the provision of multiple ecosystem functions by soils, have not been tested at the global scale. We combined correlation analysis and structural equation modelling to explore whether we could find easily measured, field-based indicators of soil multifunctionality (measured using functions linked to the cycling and storage of soil carbon, nitrogen and phosphorus). To do this, we gathered soil data from 120 dryland ecosystems from five continents. Two soil surface attributes measured in situ (litter incorporation and surface aggregate stability) were the most strongly associated with soil multifunctionality, even after accounting for geographic location and other drivers such as climate, woody cover, soil pH and soil electric conductivity. The positive relationships between surface stability and litter incorporation on soil multifunctionality were greater beneath the canopy of perennial vegetation than in adjacent, open areas devoid of vascular plants. The positive associations between surface aggregate stability and soil functions increased with increasing mean annual temperature. Synthesis and applications. Our findings demonstrate that a reduced suite of easily measured in situ soil surface attributes can be used as potential indicators of soil multifunctionality in drylands world-wide. These attributes, which relate to plant litter (origin, incorporation, cover), and surface stability, are relatively cheap and easy to assess with minimal training, allowing operators to sample many sites across widely varying climatic areas and soil types. The correlations of these variables are comparable to the influence of climate or soil, and would allow cost-effective monitoring of soil multifunctionality under changing land-use and environmental conditions. This would provide important information for evaluating the ecological impacts of land degradation, desertification and climate change in drylands world-wide.Fil: Eldridge, David J.. University of New South Wales; AustraliaFil: Delgado Baquerizo, Manuel. Universidad Rey Juan Carlos; EspañaFil: Quero, José L.. Universidad de Córdoba; EspañaFil: Ochoa, Victoria. Universidad Rey Juan Carlos; España. Universidad de Alicante; EspañaFil: Gozalo, Beatriz. Universidad Rey Juan Carlos; España. Universidad de Alicante; EspañaFil: García Palacios, Pablo. Universidad Rey Juan Carlos; EspañaFil: Escolar, Cristina. Universidad Rey Juan Carlos; EspañaFil: García Gómez, Miguel. Universidad Politécnica de Madrid; EspañaFil: Prina, Aníbal. Universidad Nacional de La Pampa; ArgentinaFil: Bowker, Mathew A.. Northern Arizona University; Estados UnidosFil: Bran, Donaldo Eduardo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche; ArgentinaFil: Castro, Ignacio. Universidad Experimental Simón Rodríguez; VenezuelaFil: Cea, Alex. Universidad de La Serena; ChileFil: Derak, Mchich. No especifíca;Fil: Espinosa, Carlos I.. Universidad Técnica Particular de Loja; EcuadorFil: Florentino, Adriana. Universidad Central de Venezuela; VenezuelaFil: Gaitán, Juan José. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Suelos; Argentina. Universidad Nacional de Luján. Departamento de Tecnología; ArgentinaFil: Gatica, Mario Gabriel. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Departamento de Biología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Centro de Investigaciones de la Geosfera y Biosfera. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones de la Geosfera y Biosfera; ArgentinaFil: Gómez González, Susana. Universidad de Cádiz; EspañaFil: Ghiloufi, Wahida. Université de Sfax; TúnezFil: Gutierrez, Julio R.. Universidad de La Serena; ChileFil: Guzman, Elizabeth. Universidad Técnica Particular de Loja; EcuadorFil: Hernández, Rosa M.. Universidad Experimental Simón Rodríguez; VenezuelaFil: Hughes, Frederic M.. Universidade Estadual de Feira de Santana; BrasilFil: Muiño, Walter. Universidad Nacional de La Pampa; ArgentinaFil: Monerris, Jorge. No especifíca;Fil: Ospina, Abelardo. Universidad Central de Venezuela; VenezuelaFil: Ramírez, David A.. International Potato Centre; PerúFil: Ribas Fernandez, Yanina Antonia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Centro de Investigaciones de la Geosfera y Biosfera. Universidad Nacional de San Juan. Facultad de Ciencias Exactas Físicas y Naturales. Centro de Investigaciones de la Geosfera y Biosfera; ArgentinaFil: Romão, Roberto L.. Universidade Estadual de Feira de Santana; BrasilFil: Torres Díaz, Cristian. Universidad del Bio Bio; ChileFil: Koen, Terrance B.. No especifíca;Fil: Maestre, Fernando T.. Universidad Rey Juan Carlos; España. Universidad de Alicante; Españ
Surface indicators are correlated with soil multifunctionality in global drylands
1. Multiple ecosystem functions need to be considered simultaneously to manage and protect the several ecosystem services that are essential to people and their environments. Despite this, cost effective, tangible, relatively simple and globally relevant methodologies to monitor in situ soil multifunctionality, that is, the provision of multiple ecosystem functions by soils, have not been tested at the global scale. 2. We combined correlation analysis and structural equation modelling to explore whether we could find easily measured, field‐based indicators of soil multifunctionality (measured using functions linked to the cycling and storage of soil carbon, nitrogen and phosphorus). To do this, we gathered soil data from 120 dryland ecosystems from five continents. 3. Two soil surface attributes measured in situ (litter incorporation and surface aggregate stability) were the most strongly associated with soil multifunctionality, even after accounting for geographic location and other drivers such as climate, woody cover, soil pH and soil electric conductivity. The positive relationships between surface stability and litter incorporation on soil multifunctionality were greater beneath the canopy of perennial vegetation than in adjacent, open areas devoid of vascular plants. The positive associations between surface aggregate stability and soil functions increased with increasing mean annual temperature. 4. Synthesis and applications. Our findings demonstrate that a reduced suite of easily measured in situ soil surface attributes can be used as potential indicators of soil multifunctionality in drylands world‐wide. These attributes, which relate to plant litter (origin, incorporation, cover), and surface stability, are relatively cheap and easy to assess with minimal training, allowing operators to sample many sites across widely varying climatic areas and soil types. The correlations of these variables are comparable to the influence of climate or soil, and would allow cost‐effective monitoring of soil multifunctionality under changing land‐use and environmental conditions. This would provide important information for evaluating the ecological impacts of land degradation, desertification and climate change in drylands world‐wide.This work was funded by the European Research Council ERC Grant agreement 242658 (BIOCOM). CYTED funded networking activities (EPES, Acción 407AC0323). D.J.E. acknowledges support from the Australian Research Council (DP150104199) and F.T.M. support from the European Research Council (BIODESERT project, ERC Grant agreement no 647038), from the Spanish Ministerio de Economía y Competitividad (BIOMOD project, ref. CGL2013-44661-R) and from a Humboldt Research Award from the Alexander von Humboldt Foundation. M.D.-B. was supported by REA grant agreement no 702057 from the Marie Sklodowska-Curie Actions of the Horizon 2020 Framework Programme H2020-MSCA-IF-2016), J.R.G. acknowledges support from CONICYT/FONDECYT no 1160026
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