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1.
J Assist Reprod Genet ; 36(5): 905-913, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30887159

RESUMEN

PURPOSE: We first assessed regulation of FGF2 expression in cumulus cells by FSH and oocyte-secreted factors during in vitro maturation (IVM). Then, we tested the hypothesis that FGF2 regulates meiotic progression, cumulus expansion, and apoptosis in cumulus-oocyte complexes (COC) undergoing IVM. METHODS: In vitro maturation of bovine COC was utilized as a model to assess regulation of FGF2 expression by FSH and oocyte-secreted factors (via microsurgical removal of the oocyte), as well as effects of graded doses of FGF2 on meiotic progression, degree of cumulus expansion, dissociation of cumulus cells, and cumulus cells apoptosis. Expression of genes regulating functional endpoints altered by FGF2 treatment was assessed in cumulus cells by real-time PCR. Cultures were replicated 4-5 times and effects of treatments were tested by ANOVA. RESULTS: FGF2 mRNA expression was increased by FSH and oocyte-secreted factors during IVM. Addition of FGF2 to the IVM medium advanced meiosis resumption, decreased the ease with which cumulus cells were dissociated, and inhibited cumulus cells apoptosis. Decreased cumulus dissociation was accompanied by decreased expression of TNFAIP6. CONCLUSIONS: This is the first study showing that FGF2 expression is regulated by the oocyte in cumulus cells. Moreover, we report novel effects of FGF2 on cumulus cell survival and extracellular matrix (ECM) quality during IVM that may favor acquisition of developmental competence and suggest physiological roles during the final steps of COC differentiation.


Asunto(s)
Blastocisto/citología , Diferenciación Celular , Células del Cúmulo/citología , Factor 2 de Crecimiento de Fibroblastos/farmacología , Técnicas de Maduración In Vitro de los Oocitos/métodos , Oocitos/citología , Animales , Apoptosis , Blastocisto/efectos de los fármacos , Blastocisto/metabolismo , Bovinos , Células del Cúmulo/efectos de los fármacos , Células del Cúmulo/metabolismo , Técnicas de Cultivo de Embriones , Desarrollo Embrionario , Femenino , Meiosis , Oocitos/efectos de los fármacos , Oocitos/metabolismo
2.
Anim Reprod ; 15(Suppl 1): 727-736, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-36249849

RESUMEN

The efficiency of in vitro assisted reproductive technologies, consisting of the transfer of embryos obtained in vitro through in vitro maturation, in vitro fertilization and early embryo culture is still limited. The quality of the oocytes is pivotal for assisted reproductive efficiency and the maturation of the oocyte represents the first key limiting step of the in vitro embryo production system. At the time of removal from the antral follicles, the oocyte is still completing the final growth and differentiation steps, needed to provide the so-called developmental competence, i.e. the machinery required to sustain fertilization and embryo development. In mono-ovular species only one oocyte per cycle is available for procreation, therefore the current assisted reproduction techniques strive to overcome this natural boundary. However, the success is still limited and overall the effectiveness does not exceed the efficiency achieved in millions of years of mammalian evolution. One of the problems lies in the intrinsic heterogeneity of the oocytes that are subjected to in vitro maturation and in the lack of dedicated in vitro approaches to finalize the differentiation process. In this review we will try to overview some of the salient aspects of current practices by emphasizing the most critical and fundamental features in oocyte differentiation that should be carefully considered for improving current techniques.

3.
Anim. Reprod. (Online) ; 15(supl. 1): 727-736, set. 2018. ilus, graf
Artículo en Inglés | VETINDEX | ID: biblio-1461394

RESUMEN

The efficiency of in vitro assisted reproductive technologies, consisting of the transfer of embryos obtained in vitro through in vitro maturation, in vitro fertilization and early embryo culture is still limited. The quality of the oocytes is pivotal for assisted reproductive efficiency and the maturation of the oocyte represents the first key limiting step of the in vitro embryo production system. At the time of removal from the antral follicles, the oocyte is still completing the final growth and differentiation steps, needed to provide the so-called developmental competence, i.e. the machinery required to sustain fertilization and embryo development. In mono-ovular species only one oocyte per cycle is available for procreation, therefore the current assisted reproduction techniques strive to overcome this natural boundary. However, the success is still limited and overall the effectiveness does not exceed the efficiency achieved in millions of years of mammalian evolution. One of the problems lies in the intrinsic heterogeneity of the oocytes that are subjected to in vitro maturation and in the lack of dedicated in vitro approaches to finalize the differentiation process. In this review we will try to overview some of the salient aspects of current practices by emphasizing the most critical and fundamental features in oocyte differentiation that should be carefully considered for improving current techniques


Asunto(s)
Animales , Fertilización In Vitro , Fertilización In Vitro/tendencias , Técnicas de Maduración In Vitro de los Oocitos/tendencias , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Cromatina Sexual
4.
Anim. Reprod. ; 15(supl. 1): 727-736, set. 2018. ilus, graf
Artículo en Inglés | VETINDEX | ID: vti-740153

RESUMEN

The efficiency of in vitro assisted reproductive technologies, consisting of the transfer of embryos obtained in vitro through in vitro maturation, in vitro fertilization and early embryo culture is still limited. The quality of the oocytes is pivotal for assisted reproductive efficiency and the maturation of the oocyte represents the first key limiting step of the in vitro embryo production system. At the time of removal from the antral follicles, the oocyte is still completing the final growth and differentiation steps, needed to provide the so-called developmental competence, i.e. the machinery required to sustain fertilization and embryo development. In mono-ovular species only one oocyte per cycle is available for procreation, therefore the current assisted reproduction techniques strive to overcome this natural boundary. However, the success is still limited and overall the effectiveness does not exceed the efficiency achieved in millions of years of mammalian evolution. One of the problems lies in the intrinsic heterogeneity of the oocytes that are subjected to in vitro maturation and in the lack of dedicated in vitro approaches to finalize the differentiation process. In this review we will try to overview some of the salient aspects of current practices by emphasizing the most critical and fundamental features in oocyte differentiation that should be carefully considered for improving current techniques(AU)


Asunto(s)
Animales , Técnicas de Maduración In Vitro de los Oocitos/tendencias , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Fertilización In Vitro/tendencias , Fertilización In Vitro , Cromatina Sexual
5.
Reprod Fertil Dev ; 29(11): 2217-2224, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28356185

RESUMEN

In vivo, oocyte maturation is triggered by the ovulatory LH surge, whereas in vitro it is precociously induced when the cumulus-oocyte complex is removed from the follicle. Natriuretic peptide C (NPPC) delays germinal vesicle breakdown (GVBD) while increasing oocyte-cumulus communication during in vitro maturation (IVM) in cattle. In the present study we first tested the hypothesis that steroids secreted by the follicle (17ß-oestradiol, progesterone and androstenedione) interact with NPPC to delay GVBD and to maintain oocyte-cumulus communication as assessed by transfer of a dye (Lucifer Yellow) from the oocyte to cumulus cells. Then, we assessed the effects of steroid hormones and NPPC, alone and in combination in a pre-IVM culture, on embryo production. The combination of NPPC with steroids delayed GVDB, increased natriuretic peptide receptor 2 (NPR2) mRNA abundance in cumulus cells during culture, and maintained oocyte-cumulus communication at levels not different from non-cultured controls. The addition of steroids and/or NPPC to a pre-IVM culture did not alter blastocyst rates after IVF, but supplementation with steroids increased blastocyst total cell number. The present study provides evidence, for the first time in cattle, that steroids interact with NPPC to regulate oocyte nuclear maturation and oocyte-cumulus communication, and improve oocyte developmental competence.


Asunto(s)
Androstenodiona/farmacología , Células del Cúmulo/metabolismo , Estradiol/farmacología , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Péptido Natriurético Tipo-C/farmacología , Oocitos/metabolismo , Progesterona/farmacología , Animales , Bovinos , Células del Cúmulo/efectos de los fármacos , Femenino , Oocitos/efectos de los fármacos , Oogénesis/efectos de los fármacos , Folículo Ovárico/metabolismo
6.
Reproduction ; 152(5): 481-9, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27492081

RESUMEN

In vitro maturation (IVM) of oocytes in cattle is inefficient, and there is great interest in the development of approaches to improve maturation and fertilization rates. Intraovarian signalling molecules are being explored as potential additives to IVM media. One such factor is kit ligand (KITL), which stimulates the growth of oocytes. We determined if KITL enhances oocyte maturation in cattle. The two main isoforms of KITL (KITL1 and KITL2) were expressed in bovine cumulus-oocyte complexes (COC), and levels of mRNA increased during FSH-stimulated IVM. The addition of KITL to the culture medium increased the percentage of oocytes that reached meiosis II but did not affect cumulus expansion after 22 h of IVM. Addition of KITL reduced the levels of mRNA encoding natriuretic peptide precursor C (NPPC), a protein that holds oocytes in meiotic arrest, and increased the levels of mRNA encoding YBX2, an oocyte-specific factor involved in meiosis. Removal of the oocyte from the COC resulted in increased KITL mRNA levels and decreased NPPC mRNA levels in cumulus cells, and addition of denuded oocytes reversed these effects. Taken together, our results suggest that KITL enhances bovine oocyte nuclear maturation through a mechanism that involves NPPC, and that the oocyte regulates cumulus expression of KITL mRNA.


Asunto(s)
Células del Cúmulo/citología , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Péptido Natriurético Tipo-C/metabolismo , Oocitos/citología , Oogénesis/fisiología , Factor de Células Madre/metabolismo , Animales , Bovinos , Células del Cúmulo/metabolismo , Femenino , Fertilización In Vitro , Meiosis/fisiología , Oocitos/metabolismo
7.
Arq. gastroenterol ; Arq. gastroenterol;44(4): 332-339, out.-dez. 2007. graf
Artículo en Portugués | LILACS | ID: lil-476188

RESUMEN

RACIONAL: Estudos epidemiológicos sobre doenças inflamatórias intestinais no Brasil são limitados devido a dificuldades diagnósticas e reduzidas amostras populacionais estudadas. A maioria dos estudos de sua prevalência disponível é composta por amostras de pacientes sob acompanhamento em ambulatório, entretanto a análise do perfil de pacientes com doenças inflamatórias intestinais hospitalizados pode auxiliar na detecção de marcadores preditivos de sua gravidade, o que permitirá intervenções médicas precoces visando a redução da taxa de hospitalização e os gastos do sistema de saúde. OBJETIVOS: Descrever o perfil social, clínico, laboratorial e antropométrico dos pacientes adultos com doenças inflamatórias intestinais internados em hospital universitário terciário. MÉTODOS: Estudo prospectivo com 43 pacientes com doenças inflamatórias intestinais internados nas enfermarias clínicas e cirúrgicas e no setor de emergência do Hospital Universitário Clementino Fraga Filho da Universidade Federal do Rio de Janeiro, RJ. Foram caracterizados dados demográficos, presença de co-morbidades, localização e comportamento clínico, história cirúrgica, manifestações extra-intestinais utilizando-se definições padronizadas. Os resultados laboratoriais foram verificados nos prontuários e as medidas antropométricas foram realizadas durante a entrevista. RESULTADOS: A maioria dos pacientes apresentou doença de Crohn (72,1 por cento), com localização íleo-colônica (60 por cento) e com comportamento penetrante (77,4 por cento), enquanto no grupo retocolite ulcerativa idiopática predominou a pancolite (50 por cento). No grupo total de retocolite ulcerativa idiopática, a artralgia foi a manifestação extra-intestinal mais freqüente (44,2 por cento) e 97,7 por cento já havia apresentado algum tipo de complicação relacionada à doença de base. Apesar do uso de terapêutica específica para doenças inflamatórias intestinais prévio à hospitalização em 79,1 por cento...


BACKGROUND: The epidemiologic survey in Brazil is limited probably due to a diagnosis deficiency and a small number of population-based studies performed. The majority of the prevalence studies available have evaluated inflammatory bowel diseases outpatients, but the knowledge of the profile of inflammatory bowel diseases inpatients is important in order to detect predictive markers of disease severity that will allow earlier medical intervention decreasing the rate of hospitalization and reducing the Health System costs. AIM: To determine social, clinical, laboratorial and anthropometric profiles of hospitalized adults inflammatory bowel diseases patients of a tertiary university hospital. METHODS: Prospective study was performed with 43 inflammatory bowel diseases inpatients from clinical and surgical wards and emergency section of university hospital. We characterized demographic data, presence of comorbidities, disease location and behavior, surgical past-history, extra intestinal manifestations using standardized definitions. Laboratory results were abstracted from medical records and anthropometric measures were performed during our visit. RESULTS: The vast majority of the inflammatory bowel diseases patients had Crohn's disease (72.1 percent), with ileocolic involvement (60 percent), with a penetrating disease behavior (77.4 percent) while ulcerative colitis group presented mostly pancolitis (50 percent). Articular pain was the most common (44.2 percent) extra intestinal manifestation of inflammatory bowel diseases patients and 97.7 percent of them had at least one type of complication related to disease. Although, the previous use of specific medical therapies to inflammatory bowel diseases before the hospitalization (more frequently corticosteroids) was done (79 percent), the majority of the patients were hospitalized because of inflammatory bowel diseases activity. Disease activity was present in 80.7 percent of Crohn's disease...


Asunto(s)
Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Colitis Ulcerosa , Enfermedad de Crohn , Pesos y Medidas Corporales , Brasil , Colitis Ulcerosa/sangre , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/terapia , Enfermedad de Crohn/sangre , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/terapia , Hospitales Universitarios , Estudios Prospectivos , Factores Socioeconómicos
8.
Arq Gastroenterol ; 44(4): 332-9, 2007.
Artículo en Portugués | MEDLINE | ID: mdl-18317653

RESUMEN

BACKGROUND: The epidemiologic survey in Brazil is limited probably due to a diagnosis deficiency and a small number of population-based studies performed. The majority of the prevalence studies available have evaluated inflammatory bowel diseases outpatients, but the knowledge of the profile of inflammatory bowel diseases inpatients is important in order to detect predictive markers of disease severity that will allow earlier medical intervention decreasing the rate of hospitalization and reducing the Health System costs. AIM: To determine social, clinical, laboratorial and anthropometric profiles of hospitalized adults inflammatory bowel diseases patients of a tertiary university hospital. METHODS: Prospective study was performed with 43 inflammatory bowel diseases inpatients from clinical and surgical wards and emergency section of university hospital. We characterized demographic data, presence of comorbidities, disease location and behavior, surgical past-history, extra intestinal manifestations using standardized definitions. Laboratory results were abstracted from medical records and anthropometric measures were performed during our visit. RESULTS: The vast majority of the inflammatory bowel diseases patients had Crohn's disease (72.1%), with ileocolic involvement (60%), with a penetrating disease behavior (77.4%) while ulcerative colitis group presented mostly pancolitis (50%). Articular pain was the most common (44.2%) extra intestinal manifestation of inflammatory bowel diseases patients and 97.7% of them had at least one type of complication related to disease. Although, the previous use of specific medical therapies to inflammatory bowel diseases before the hospitalization (more frequently corticosteroids) was done (79%), the majority of the patients were hospitalized because of inflammatory bowel diseases activity. Disease activity was present in 80.7% of Crohn's disease and 50% ulcerative colitis patients. Inflammatory bowel diseases mortality rate was 5.5% (2/36). Comorbidities presence occurred only in 30.2% of inflammatory bowel diseases patients. The predominant surgery performed was intestinal resection. The interval between the symptoms appearance and the definitive diagnosis was less than 1 year in more than 70% of inflammatory bowel diseases patients. Laboratory findings detected were a decreased serum albumin (85.7%) and anemia (69.8%). The majority of the patients had at least one anthropometric alteration. The social stratification of the inflammatory bowel diseases group was similar to the Brazilian population. CONCLUSION: The inflammatory bowel diseases inpatients from the university hospital wards had more severe evolution of these illnesses with an active and extensive disease with complications and frequent extra intestinal manifestations, despite the prolonged use of corticosteroids. The higher prevalence of Crohn's disease inpatients than ulcerative colitis could reflect a higher aggressive behavior of this disease. The reduced serum albumin, anemia and anthropometric alterations are common inflammatory bowel diseases inpatients and could be related to a major severity of inflammatory bowel diseases evolution.


Asunto(s)
Colitis Ulcerosa , Enfermedad de Crohn , Adolescente , Adulto , Anciano , Pesos y Medidas Corporales , Brasil , Colitis Ulcerosa/sangre , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/terapia , Enfermedad de Crohn/sangre , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/terapia , Femenino , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores Socioeconómicos
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