RESUMEN
Protein content was measured in zona-free bovine oocytes and pre-elongation stage embryos, following in vitro maturation, fertilisation, and then culture in Synthetic Oviduct Fluid medium supplemented with amino acids and 8 mg ml(-1) bovine serum albumin (BSA). Values (ng embryo(-1)) of 122 +/- 7.8, 137 +/- 8.6, 111 +/- 8.8, 115 +/- 10.4, 139 +/- 9.0 and 152 +/- 10.1 were obtained for zona-free mature oocytes, 2-cell (day 2), 8-cell (day 3), compact morula (day 6), blastocyst (day 7), and expanded blastocyst (day 8) stage embryos, respectively. The protein content of day 7 zona-enclosed blastocysts was 337 +/- 58.0 ng embryo(-1). These values suggest that prior to compaction and blastulation, the early cleavage stage bovine embryo has a higher rate of protein degradation than that of synthesis. Net growth is observed only after initiation of compaction. The protein content of day 7 blastocysts was measured in embryos following in vitro production and culture in the same media supplemented with either 0.5% w/v polyvinyl alcohol (PVA), 8 mg ml(-1) BSA, 8 mg ml(-1) BSA and further supplemented with 10% fetal calf serum (FCS) from the beginning of culture (FCS-D1), 8 mg ml(-1) BSA and 10% FCS from the fourth day of culture (day 5 of development) or from in vivo-derived day 7 blastocysts. Protein content was significantly (P < 0.05) lower in PVA-cultured embryos than other treatments. To determine if this difference in PVA-cultured embryos was due to a difference in the rate of protein synthesis, comparisons were made between day 7 embryos derived from BSA-culture and either PVA-culture, FCS-D1 culture or in vivo-derived embryos. Despite differences in diameter, no significant difference was observed in the incorporation of L-[2,3,4,5,6-3H]-phenylalanine into the TCA-precipitable fraction in any of the three comparisons made. However, incubation in the presence of FITC-abelled BSA or beta-casein and examination under either fluorescence or confocal microscopy revealed that protein in the extra-embryonic environment was actively taken up by the trophectoderm of day 7 blastocysts, most likely by endocytosis. These results suggest that exogenous protein is an important nutritive source, probably maintaining intracellular amino acid pools. Results obtained from the production of em bryos in protein-free medium should be viewed with the knowledge that such embryos differ metabolically from those embryos grown in the presence of protein, including in vivo-derived embryos.
Asunto(s)
Embrión de Mamíferos/metabolismo , Proteínas/metabolismo , Animales , Caseínas/metabolismo , Bovinos , Técnicas de Cultivo , Desarrollo Embrionario y Fetal , Femenino , Masculino , Oocitos/metabolismo , Fenilalanina/metabolismo , Biosíntesis de Proteínas , Albúmina Sérica Bovina/metabolismoRESUMEN
Two experiments were conducted to examine the effect of membrane stabilization through the modification of in vitro culture medium or freezing medium on post-thaw survival of in vitro-produced bovine embryos. In Experiment 1, Day 7 (Day 0 = day of IVF) late morulae and blastocysts that developed following culture in SOF/aa/BSA (IVC medium) were frozen slowly to -35 degrees C in the presence of 1.5 M ethylene glycol prepared in ovum culture medium (OCM) or in OCM supplemented with 10, 25 or 50% fetal calf serum (FCS) or 5, 10 or 25 mg/mL BSA. Post-thaw survival was assessed by re-expansion and/or hatching following 48 h of culture in IVC medium + 10% FCS. Overall, survival was significantly (P < 0.01) affected by embryo stage, with more hatched blastocysts surviving (71%) than blastocysts (59%) or late morulae (51%). Addition of FCS significantly (P < 0.01) reduced survival compared with control embryos or those frozen in BSA-supplemented medium (50.48 vs 68.01 vs 63.53%, respectively). There was also a significant interaction between embryo stage and protein type (P < 0.05). The survival of late morulae/early blastocysts following freezing was improved in the presence of additional BSA but not FCS. In Experiment 2, the IVC medium was supplemented with liposomes containing lecithin, sphingomyelin and cholesterol. Sphingomyelin and cholesterol at ratios of 1:1, 1:4 and 4:1 were added to 50, 100 or 150 micrograms/mL lecithin to yield a final lipid concentration of 200 micrograms/mL. A further group contained 200 micrograms/mL lecithin only. Blastocysts were frozen in 1.5 M ethylene glycol in OCM, then thawed and assessed as in Experiment 1. The presence of liposomes during IVC did not affect the proportion of cleaved embryos that developed to blastocysts or survival following freezing. However, the survival of blastocysts that developed in the presence of 200 micrograms/mL lecithin only was significantly lower than in any other treatment (6%; P < 0.03). These studies demonstrate that the protein composition of the freezing medium can significantly affect survival after thawing and that the survival of late morulae can be improved with additional BSA. The presence of lecithin only in the liposome preparation did not affect embryo development, but significantly reduced survival after freezing, suggesting it can affect post-thaw embryo survival, perhaps by altering embryonic membrane composition.
Asunto(s)
Bovinos/embriología , Criopreservación , Embrión de Mamíferos/fisiología , Fertilización In Vitro/veterinaria , Liposomas , Animales , Blastocisto/fisiología , Colesterol/administración & dosificación , Desarrollo Embrionario y Fetal , Femenino , Mórula/fisiología , Esfingomielinas/administración & dosificaciónRESUMEN
Although the cause of ovarian cancer is unknown, the risk of developing the disease increases with age. Postmenopausal uterine bleeding is assumed to be caused by endometrial cancer until proven otherwise by adequate cytologic or histologic sampling of the endometrium. Older women need to be educated as to the benefits of regular pelvic examinations and Papanicolaou smears.
Asunto(s)
Neoplasias de los Genitales Femeninos/terapia , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Compuestos de Cromo/administración & dosificación , Compuestos de Cromo/uso terapéutico , Terapia Combinada , Neoplasias Endometriales/terapia , Femenino , Humanos , Inyecciones Intraperitoneales , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/cirugía , Fosfatos/administración & dosificación , Fosfatos/uso terapéutico , Neoplasias del Cuello Uterino/terapiaRESUMEN
Women diagnosed with early stage ovarian cancer may be considered for adjuvant therapy. Intraperitoneal chromic phosphate (P-32) is commonly used in these patients with few complications. A woman found to have early stage ovarian cancer was given intraperitoneal P-32 in the presence of a lingering pelvic infection, which is usually not mentioned as a contraindication to its use. Radiation damage to the small bowel and cecum developed as did damage to the ureter and bladder, which then required surgery.