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3.
J Anim Sci Biotechnol ; 12(1): 32, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33583428

RESUMEN

BACKGROUND: In vitro embryo production (IVP) and embryo transfer (ET) are two very common assisted reproductive technologies (ART) in human and cattle. However, in pig, the combination of either procedures, or even their use separately, is still considered suboptimal due to the low efficiency of IVP plus the difficulty of performing ET in the long and contorted uterus of the sow. In addition, the potential impact of these two ART on the health of the offspring is unknown. We investigated here if the use of a modified IVP system, with natural reproductive fluids (RF) as supplements to the culture media, combined with a minimally invasive surgery to perform ET, affects the output of the own IVP system as well as the reproductive performance of the mother and placental molecular traits. RESULTS: The blastocyst rates obtained by both in vitro systems, conventional (C-IVP) and modified (RF-IVP), were similar. Pregnancy and farrowing rates were also similar. However, when compared to in vivo control (artificial insemination, AI), litter sizes of both IVP groups were lower, while placental efficiency was higher in AI than in RF-IVP. Gene expression studies revealed aberrant expression levels for PEG3 and LUM in placental tissue for C-IVP group when compared to AI, but not for RF-IVP group. CONCLUSIONS: The use of reproductive fluids as additives for the culture media in pig IVP does not improve reproductive performance of recipient mothers but could mitigate the impact of artificial procedures in the offspring.

4.
Ann Biomed Eng ; 48(6): 1805-1820, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32215754

RESUMEN

The main goal of this study is the quantification of the particle transport and deposition within the human airways during light, normal and exercise breathing conditions using the computational fluid dynamics. In particular we presented a comparison between healthy and stented airways. The considered tracheobronchial model is based on the Weibel symmetric model in which we have inserted the Dumon prosthesis at different locations and on the CT-based geometries of a healthy and a stented airway. The results indicate an important redistribution of the particle deposition locations. Local overdoses can be found in the proximal regions of the prostheses, independently of the breathing conditions, of the particle size and of the considered geometry. The presented work is aimed to contribute to the understanding of the particle deposition in the human lung and to improve drug-aerosol therapies. For patients that underwent airways reconstructive surgery, it can give detailed information about the deposition efficiency and it may help targeting specific airways regions.


Asunto(s)
Modelos Biológicos , Fenómenos Fisiológicos Respiratorios , Sistema Respiratorio/metabolismo , Adulto , Aerosoles , Humanos , Hidrodinámica , Modelación Específica para el Paciente , Sistema Respiratorio/diagnóstico por imagen , Stents
5.
Anim Reprod Sci ; 127(1-2): 62-72, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21784589

RESUMEN

In this study, different combinations of 2-step, discontinuous gradient centrifugation were used, consisting of three different combinations of isotonic Percoll (45/60, 60/75 and 45/90%) that allowed us to select different sperm subpopulations from fertile and normozoospermic boars. Our objective in this study is to evaluate the effects of centrifugation through three different discontinuous Percoll gradients on sperm function parameters (motility, viability, morphology, acrosome status, chromatin condensation, DNA fragmentation, ROS generation, tyrosine phosphorylation and intracellular calcium concentration) and the sperm penetrating capacity in an IVF system. All the Percoll treatments evaluated increased the percentage of spermatozoa with normal morphology, the proportion of un-damaged DNA, normal chromatin condensation, motion parameters measured by CASA and the percentage of capacitated spermatozoa with tyrosine phosphorylated proteins compared to control group. Finally, the in vitro oocyte penetrating capacity of boar spermatozoa was significantly affected by Percoll centrifugation. All the Percoll treatments increased the penetration rates and mean number of sperm per penetrated oocyte. Despite the efficiency of all three of the sperm treatments tested in selecting spermatozoa with improved sperm parameters and capacity to penetrate oocytes in vitro, the optimum performance of this system was demonstrated after preselecting spermatozoa by centrifugation on a discontinuous 45/90 Percoll gradient. The P45/90 treatment leads to obtain a higher percentage of spermatozoa which develop properly the capacitation process as it was shown measuring tyrosine phosphorylation and intracellular calcium concentration.


Asunto(s)
Centrifugación por Gradiente de Densidad/veterinaria , Povidona/farmacología , Dióxido de Silicio/farmacología , Espermatozoides/fisiología , Porcinos/fisiología , Acrosoma/fisiología , Animales , Centrifugación por Gradiente de Densidad/métodos , Fragmentación del ADN , Femenino , Citometría de Flujo/veterinaria , Inmunohistoquímica/veterinaria , Etiquetado Corte-Fin in Situ/veterinaria , Masculino , Microscopía de Contraste de Fase/veterinaria , Motilidad Espermática/fisiología , Interacciones Espermatozoide-Óvulo/fisiología , Espermatozoides/ultraestructura
6.
Reproduction ; 125(1): 133-41, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12622703

RESUMEN

This study was designed to determine the effect of different sperm preparation treatments before IVF on the acrosome reaction, oocyte penetration time, early embryo development and timing of female and male pronucleus formation. Pooled sperm-rich fractions were (i) washed in PBS, (ii) left unwashed, or (iii) layered in a Percoll gradient. In Expt 1, the proportion of acrosome-reacted spermatozoa, determined by staining with fluorescein isothyocyanate-labelled peanut agglutinin lectin and propidium iodide, was highest after treatment with Percoll (P < 0.001). In Expt 2, oocytes matured in vitro were co-cultured with spermatozoa for 2, 4 or 6 h. Attached spermatozoa were then removed and the oocytes were cultured in fresh IVF medium for 16 h. Both sperm treatment and co-culture time were found to affect penetrability and monospermy rates (P < 0.001); spermatozoa treated with Percoll showed fastest oocyte penetration and highest penetrability. In Expt 3, matured oocytes were co-incubated with spermatozoa pretreated by the three above mentioned procedures (i, ii, iii) for 2, 6 and 2 h respectively. Putative zygotes were then washed and transferred to medium NCSU-23 until the blastocyst stage. In this experiment, sperm treatment had a significant effect on the cleavage rate (P < 0.001) and rate of blastocyst formation (P < 0.05); the group treated with Percoll showed the highest rate of blastocyst formation. Finally, in Expt 4, timing of female and male pronucleus formation for each sperm treatment was determined 4, 6 and 8 h after insemination. The time of female and male pronucleus formation was affected by the sperm treatment and was faster for the Percoll group (P < 0.05). The findings of the present study indicate that treatment with Percoll yields the best results in this in vitro pig embryo production system.


Asunto(s)
Fertilización In Vitro/veterinaria , Manejo de Especímenes/métodos , Espermatozoides , Porcinos , Reacción Acrosómica , Análisis de Varianza , Animales , Técnicas de Cultivo de Célula/métodos , Medios de Cultivo , Desarrollo Embrionario y Fetal , Femenino , Masculino , Povidona , Dióxido de Silicio , Cigoto
7.
Anim Reprod Sci ; 68(1-2): 85-98, 2001 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-11600277

RESUMEN

This study was designed to determine the effect of co-culture with porcine oviductal epithelial cell (POEC) monolayers on in vitro fertilization of pig oocytes. The in vitro penetrability of mature (experiment 1) or immature (experiment 2) oocytes was studied in presence or absence of POEC during IVF with fresh semen. In experiment 3, boar and POEC effects were analyzed but in this case with frozen-thawed spermatozoa. In experiment 4, the spermatozoa were pre-incubated before IVF with or without POEC in order to assess their effect on IVF sperm-related parameters. In experiment 5, the effect of POEC was studied by co-culturing them with oocytes before IVF to determine if monospermy was improved. The results showed that high sperm concentration and POEC increase oocyte penetrability (P<0.01) and decrease monospermy rate (P<0.01), in both mature and immature oocytes (P<0.01) with fresh semen and a 18 h culture time. With frozen semen was detected a boar and POEC effect (P<0.01) on penetration rate. The sperm pre-culture 2 h with POEC also resulted in an increase of sperm penetration in terms of number of sperm per oocyte (P<0.01) and this treatment did not increase monospermy when contact time between gametes was limited to 6 h although monospermy was higher when POEC were present during IVF. Finally, exposure of oocytes to POEC for 4 h before IVF facilitated monospermic penetration to over 70% (P<0.01). In conclusion, the use of POEC in porcine IVF systems provides the possibility of working with low sperm concentrations and the effect of POEC on monospermy depends on sperm concentration, boar and contact time between gametes. Moreover, the exposure of oocytes to POEC before IVF improves the rate of monospermy.


Asunto(s)
Fertilización In Vitro/veterinaria , Oocitos/fisiología , Oviductos/fisiología , Espermatozoides/fisiología , Porcinos/fisiología , Animales , Células Cultivadas , Técnicas de Cocultivo , Criopreservación/veterinaria , Células Epiteliales , Femenino , Masculino , Oviductos/citología , Preservación de Semen/veterinaria , Capacitación Espermática , Interacciones Espermatozoide-Óvulo
8.
Theriogenology ; 54(9): 1343-57, 2000 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11191860

RESUMEN

This study was designed to evaluate the relationship between sperm factors and penetration capacity in an in vitro system with immature porcine oocytes. The sperm parameters evaluated in 145 ejaculates were volume, sperm concentration, total cells in the ejaculate, ATP content, morpho-anomalies, percentage of motile sperm cells, forward progressive motility (FPM), acrosome status (NAR), hypo-osmotic swelling test (HOS), osmotic resistance test (ORT), eosin-nigrosin viability stain and sperm membrane integrity (DCF). Porcine oocytes (a total of 8,736) were used to evaluate the capacity of the different sperm assays to predict penetration. Many parameters were found to be related to in vitro penetration ability; all conventional semen parameters, except sperm concentration and eosinnigrosin staining, were significantly better in high (>75%) than in low penetration rates (<75%). When the ejaculates were preselected the number of significantly related parameters was lower. When studying all conventional semen parameters through a stepwise multiple linear regression analysis of seminal measurements, up to 72.3% of total variance of the penetration rate could be predicted. However, as many as 4 parameters were needed (FPM in fresh semen, folded tail, NAR in post-treatment semen and DCF) for accurate prediction. On the other hand, the multiple logistic regression needed 7 parameters to discriminate 83.96% of the cases correctly. In summary, the results from the present study showed that almost all studied parameters were significantly different for predicting penetration process attained or failed, but most of them were correlated together. These findings emphasize the complexity of sperm functions and the difficulty of assessing the fertilizing ability.


Asunto(s)
Fertilización In Vitro , Interacciones Espermatozoide-Óvulo , Espermatozoides/fisiología , Porcinos/fisiología , Acrosoma/fisiología , Adenosina Trifosfato/análisis , Animales , Femenino , Soluciones Hipotónicas , Modelos Lineales , Masculino , Curva ROC , Recuento de Espermatozoides , Motilidad Espermática , Espermatozoides/anomalías , Espermatozoides/química
9.
Anim Reprod Sci ; 54(2): 95-108, 1998 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-9877056

RESUMEN

A field trial was conducted to compare the fertility predicting capacity of different sperm assays applying classical semen analysis, sperm function and the homologous in vitro penetration test (hIVP) to 60 ejaculates from four boars collected over a period of 15 weeks. No differences were found between the groups of fertility (Low Fertility: < 20%; Intermediate: 40-60% and High: > 80%) for sperm-rich fraction volume collection, sperm concentration, total sperm number, cationic contents in seminal plasma and ATP concentration. Partial differences were found in the parameters of motility, normal morphology, normal apical ridge (NAR), viability with eosin-nigrosin stain, hypo-osmotic swelling test (HOS), osmotic resistance test (ORT) and functional membrane integrity (with carboxyfluorescein diacetate, DCF). These parameters would be useful for detecting sperm with poor fertility, but they are not precise enough to discriminate an ejaculate with higher fertility than the herd median. Only the penetration percentage (10.24 +/- 1.45 vs. 55.13 +/- 3.35 vs. 84.72 +/- 1.73) and sperm number per oocyte (1.29 +/- 0.07 vs. 11.29 +/- 1.79 vs. 25.86 +/- 1.43) in a hIVP system were parameters with a predictive capacity to discriminate between the three fertility groups. Consequently, hIVP was found to be the best seminal assay and it may improve the in vitro assessment of sperm fertilizing ability.


Asunto(s)
Fertilidad , Fertilización In Vitro , Semen/fisiología , Interacciones Espermatozoide-Óvulo , Porcinos/fisiología , Adenosina Trifosfato/análisis , Animales , Cationes , Femenino , Masculino , Embarazo , Análisis de Regresión , Semen/química , Semen/citología , Recuento de Espermatozoides , Motilidad Espermática , Espermatozoides/anomalías , Espermatozoides/fisiología
10.
J Hepatol ; 27(4): 639-44, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9365039

RESUMEN

BACKGROUND/AIMS: To investigate whether physicochemical alterations in plasma lipoproteins are associated with changes in plasma oncotic pressure and viscosity in liver cirrhosis. METHODS: The study included 66 patients with cirrhosis (confirmed by liver biopsy) and 58 healthy volunteers. The constituents measured were: the concentration, density and composition of plasma lipoproteins; plasma oncotic pressure and viscosity; and the concentrations of albumin, total protein, haptoglobin, transferrin, immunoglobulin M and alpha2-macroglobulin. RESULTS: Step-wise multiple regression analysis indicated that, in the patients with cirrhosis, plasma oncotic pressure was significantly correlated with plasma albumin+viscosity (r=+0.85; p<0.001) and with plasma total protein+the density of low density lipoprotein (r=+0.74; p<0.001). The inclusion of viscosity and the density of low density lipoprotein in the regression equations significantly improved the observed correlation between albumin and plasma oncotic pressure (r=+0.70; p<0.001). Similarly, plasma viscosity was significantly correlated with the sum of plasma total protein and cholesterol (r=+0.68; p<0.001). The inclusion of cholesterol in the regression equation significantly increased the observed correlation between total protein and plasma viscosity (r=+0.59; p<0.001). CONCLUSIONS: These results suggest that lipoprotein alterations associated with liver cirrhosis may play a role in determining plasma oncotic pressure and viscosity, and thus could influence the progression of the disease.


Asunto(s)
Viscosidad Sanguínea , Lipoproteínas/sangre , Cirrosis Hepática/sangre , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Presión Osmótica , Análisis de Regresión
11.
Rev. Fac. Odontol. Univ. Chile ; 10(1): 31-6, ene.-jun. 1992. tab, ilus
Artículo en Español | LILACS | ID: lil-136816

RESUMEN

Se estudió en un grupo de 102 pacientes portadores de prótesis parciales removibles los efectos producidos por éstas en el aumento de la incidencia de caries, después de 4 a 5 años de uso. Encontrándose un aumento de lesiones en las piezas pilares directas en relación al resto de las piezas que presentaban un índice de placa similar, se plantea hipótesis al respecto


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Caries Dental/epidemiología , Dentadura Parcial Removible/efectos adversos , Susceptibilidad a Caries Dentarias/fisiología , Índice de Placa Dental , Estudios de Seguimiento , Higiene Bucal/estadística & datos numéricos
12.
Rev. Fac. Odontol. Univ. Chile ; 9(2): 27-35, jul.-dic. 1991. tab, ilus
Artículo en Español | LILACS | ID: lil-136808

RESUMEN

Se estudió la presencia de áreas radiolúcidas mandibulares en una muestra de 24 pacientes con diagnóstico de osteoporosis, de sexo femenino, mediante una ortopantomografía (RX Panorámica). En estos pacientes es posible apreciar algún grado de rarefacción ósea detectable a la radiografía y que el odontólogo, al pesquizar, debe interconsultar al médico especialista y tomar las medidad pertinentes cuando efectúe la rehabilitación. Se establece el tamaño y la ubicación mas frecuente de las áreas radiolúcidas mandibulares, además de su relación con el grado de densidad ósea lumbar y femoral


Asunto(s)
Humanos , Femenino , Persona de Mediana Edad , Densidad Ósea/fisiología , Dentaduras/estadística & datos numéricos , Osteoporosis/epidemiología , Radiografía Panorámica
13.
Rev. Fac. Odontol. Univ. Chile ; 5(1): 20-5, ene.-jun. 1987. ilus
Artículo en Español | LILACS | ID: lil-56597

RESUMEN

Se utiliza el implante subperióstico circunferencial en pacientes desdentados parciales de extremo libre uni o bilateral, para proporcionar un pilar distal a cada extremo libre. La obtención de la impresión ósea se realiza mediante una impresión compuesta utilizando cubeta quirúrgica. El diseño del implante es conservador en cuanto a la ubicación de los conectores mayores, limitándolos sólo a las zonas de soporte, lo que hace menos agresivas las intervenciones quirúrgicas. Se modifica la extensión del conector mayor lingual, suprimiéndolo de la zona anterior (en relación a las piezas remanentes). Se elimina también el cuello del pilar del implante quedando cilíndrico en toda su extensión, y se modifica su extremo terminal con un escalón que sierve de guía de inserción y limita la intrusión de la prótesis. No se utilizan dispositivos de retención primaria. El paciente es luego rehabilitado mediante prótesis removible implantada, a la que se le da oclusión orgánica


Asunto(s)
Humanos , Implantación Dental Endoósea , Prótesis Dental
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