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1.
Reprod Biomed Online ; 49(1): 103976, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38733676

RESUMO

RESEARCH QUESTION: Can immature oocytes vitrified and warmed using a short protocol survive and resume meiosis? DESIGN: This study examined modifications of oocyte vitrification and warming protocols that reduce the length of exposure to vitrification and warming solutions. In total, 561 germinal vesicles and 218 metaphase I oocytes that were immature at oocyte retrieval were vitrified at room temperature for 2 min. Warming was performed at 37°C for 2 min. Resumption of meiotic activity was evaluated after 24 and 48 h of culture. Two different commercially available vitrification and warming kits were used for comparison. RESULTS: Ninety-five percent of germinal vesicles survived, with no difference observed between the kits. The survival of metaphase I oocytes was, on average, 95.4% and did not differ significantly between the kits. Of the 533 germinal vesicles that survived, 491 converted to metaphase I oocytes (92.1%). After culture for 48 h, 54.4% converted to metaphase II oocytes. In addition, of the 208 metaphase I oocytes that survived warming, 84.1% converted to metaphase II oocytes after 24 h of culture. These maturation rates were similar to those of non-vitrified oocytes. CONCLUSIONS: Vitrification and warming of oocytes at different nuclear maturation stages can be performed with 2 min of exposure to hypertonic solution and 2 min of exposure to hypotonic solution, respectively. This approach reduces exposure of the oocytes to room temperature during dehydration and rehydration. Warming in 0.5M sucrose helps to maintain and support the potential of oocytes to resume nuclear meiotic activity, and conversion from germinal vesicles to metaphase I and metaphase II oocytes.


Assuntos
Criopreservação , Meiose , Oócitos , Vitrificação , Oócitos/citologia , Oócitos/fisiologia , Humanos , Meiose/fisiologia , Feminino , Criopreservação/métodos , Sobrevivência Celular , Técnicas de Maturação in Vitro de Oócitos/métodos , Adulto
2.
J Assist Reprod Genet ; 37(4): 953-962, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32130614

RESUMO

PURPOSE: To determine whether gestational carrier (GC) in vitro fertilization (IVF) cycles (commissioned cycles) for same-sex or single male intended parents have an increased incidence of adverse perinatal outcomes compared with spontaneous cycles in the same GCs. DESIGN: GC singleton pregnancies were identified from a database of 895 commissioned cycles from a large fertility center. Of these, 78 commissioned cycles met inclusion and exclusion criteria and were compared with 71 spontaneous cycles by the same GCs. The primary outcome was the composite score for adverse perinatal outcomes. Secondary outcomes included mode of delivery, birthweight, and gestational age. Chi-square test of association and Mann-Whitney U tests were used to compare categorical and continuous variables between the cohorts, respectively. Logistic and linear regressions controlling for GC age were constructed to determine the influence of GC cycle type on adverse perinatal outcomes. RESULTS: Commissioned cycles were significantly associated with adverse perinatal outcomes (25.6% vs. 9.9%; p = 0.02) and lower average gestational age (38.7 ± 1.5 vs. 39.4 ± 0.9; p < 0.001) compared with spontaneous cycles. Commissioned cycle increased the likelihood of adverse perinatal outcomes (OR 3.3; p = 0.03) and was a significant independent predictor of a lower average gestational age (ß = 0.897; p < 0.001). There were no significant differences in the incidence of vaginal deliveries or cesarean sections between commissioned and spontaneous cycles. CONCLUSIONS: Commissioned cycles confer a greater incidence of composite perinatal complications and were independently associated with a lower average gestational age when compared with spontaneous pregnancies carried by the same GC despite a confirmed healthy uterine environment, sperm samples, and donor oocytes.


Assuntos
Fertilidade/fisiologia , Fertilização in vitro , Resultado da Gravidez , Mães Substitutas , Adulto , Peso ao Nascer , Cesárea , Transferência Embrionária , Feminino , Fertilidade/genética , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Casamento , Indução da Ovulação/métodos , Assistência Perinatal , Gravidez , Nascimento Prematuro , Estudos Retrospectivos , Transferência de Embrião Único
3.
Hum Reprod ; 26(9): 2473-85, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21669966

RESUMO

BACKGROUND: Ovarian tissue cryopreservation is an emerging fertility preservation option, and culturing follicles isolated from this tissue to obtain mature gametes may ultimately be the best solution for patients for whom transplantation is contraindicated. It is unclear, however, how patient-specific variables (including age, weight and menstrual cycle stage) impact follicle growth and quality during three-dimensional culture. METHODS: We used a mouse model to systematically determine how these variables impact in vitro follicle growth. We characterized metabolic and hormonal profiles of mice at specific ages, weights and cycle stages and secondary follicles from these cohorts were isolated and cultured. We then assessed follicle survival, growth and function, as well as meiotic competence and spindle morphology of the resulting oocytes. RESULTS: We found that older mice and mice with increased body weight had higher serum cholesterol, abnormal glucose tolerance and lower levels of circulating Anti-Müllerian hormone compared with younger and leaner controls. Secondary follicles isolated from different cohorts and grown in vitro had indistinguishable growth trajectories. However, the follicles isolated from older and heavier mice and those in diestrus had altered hormone profiles. These follicles contained oocytes with reduced meiotic competence and produced oocytes with greater spindle defects. CONCLUSIONS: These results suggest that the original physical environment of the follicle within the ovary can impact its function when isolated and cultured. These findings are valuable as we begin to use in vitro follicle growth technology for a heterogeneous fertility preservation patient population.


Assuntos
Ciclo Estral , Folículo Ovariano/fisiologia , Técnicas de Cultura de Tecidos , Fatores Etários , Animais , Hormônio Antimülleriano/sangue , Peso Corporal , Colesterol/sangue , Feminino , Preservação da Fertilidade , Glucose/metabolismo , Teste de Tolerância a Glucose , Meiose/fisiologia , Camundongos , Camundongos Endogâmicos , Oócitos/citologia , Oócitos/fisiologia , Oócitos/ultraestrutura , Fuso Acromático/ultraestrutura
4.
Minerva Med ; 100(4): 275-92, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19749682

RESUMO

Syncope is a syndrome characterized by a relatively sudden, temporary and self-terminating loss of consciousness; the causes may vary, but they have in common a temporary inadequacy of cerebral nutrient flow, usually due to a fall in systemic arterial pressure. However, while syncope is a common problem, it is only one explanation for episodic transient loss of consciousness (TLOC). Consequently, diagnostic evaluation should start with a broad consideration of real or seemingly real TLOC. Among those patients in whom TLOC is deemed to be due to ''true syncope'', the focus may then reasonably turn to assessing the various possible causes; in this regard, the neurally-mediated syncope syndromes are among the most frequently encountered. There are three common variations: vasovagal syncope (often termed the ''common'' faint), carotid sinus syndrome, and the so-called ''situational faints''. Defining whether the cause is due to a neurally-mediated reflex relies heavily on careful history taking and selected testing (e.g., tilt-test, carotid massage). These steps are important. Despite the fact that neurally-mediated faints are usually relatively benign from a mortality perspective, they are nevertheless only infrequently an isolated event; neurally-mediated syncope tends to recur, and physical injury resulting from falls or accidents, diminished quality-of-life, and possible restriction from employment or avocation are real concerns. Consequently, defining the specific form and developing an effective treatment strategy are crucial. In every case the goal should be to determine the cause of syncope with sufficient confidence to provide patients and family members with a reliable assessment of prognosis, recurrence risk, and treatment options.


Assuntos
Síncope Vasovagal , Algoritmos , Estimulação Cardíaca Artificial/métodos , Seio Carotídeo/fisiologia , Humanos , Massagem , Anamnese , Modalidades de Fisioterapia , Pressorreceptores/fisiologia , Síncope Vasovagal/diagnóstico , Síncope Vasovagal/etiologia , Síncope Vasovagal/terapia , Síndrome , Teste da Mesa Inclinada
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