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3.
Fertil Steril ; 65(2): 400-5, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8566270

RESUMO

OBJECTIVE: To develop a reliable sperm test that would predict pregnancy rate in assisted reproductive technologies. DESIGN: Blind prospective cohort study. SETTING: Tertiary-care, university hospital-affiliated IVF program. PATIENTS: One hundred nineteen sperm samples were obtained from 110 males from couples undergoing IVF or GIFT (ART). Sperm samples were washed by Percoll, incubated at 24 degrees C for 4 hours, and an aliquot of the same sperm suspension was used for ART incubated at 40 degrees C for 4 hours (stress test). Stress test scores are expressed as the ratio of final to initial motility. RESULTS: Of 119 ART cycles, 24 resulted in pregnancy. Of 24 pregnancies, 23 occurred in cycles that used sperm samples with stress test scores > or = 0.75 and only one with a stress test score < 0.75. The negative predictive value of the test, defined as the absence of pregnancy with scores < 0.75, was 98% and the positive predictive value, defined as the occurrence of pregnancy with scores > or = 0.75, was 36%. Logistic regression analysis indicated that the stress test score alone was correlated significantly with pregnancy after ART. CONCLUSION: These results indicate that stress test scores < 0.75 are predictive of poor pregnancy outcome in ART.


Assuntos
Gravidez/estatística & dados numéricos , Técnicas Reprodutivas , Motilidade dos Espermatozoides , Adulto , Feminino , Humanos , Modelos Logísticos , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , Estresse Fisiológico
4.
J Exp Zool ; 265(3): 231-9, 1993 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-8436917

RESUMO

The in vitro culture of fully grown mammalian oocytes results in spontaneous meiotic maturation from prophase arrest to metaphase II. This maturation can be inhibited by steroid hormones in both murine and porcine oocytes. Using selected steroids, we have examined the structure-activity relationships of steroids and oocyte inhibition. Experiments with androgens, estrogens, glucocorticoids, and progesterone revealed that at least one steroid from each class was inhibitory. Progesterone, however, was two to three times more effective than steroids from other classes. Examination of a variety of progestins showed that most substitutions decreased or abolished the inhibitory activity. Hydroxy group substitutions at different carbon atoms and substitutions at the 4-ene group lessened the inhibitory effectiveness, with the exception of 5 beta-dihydroprogesterone, which was as effective as progesterone. However, several steroids with substitutions at the C17 acetyl group were more active than progesterone, including 20 beta-dihydroprogesterone which was the most inhibitory steroid tested (ID50 = 5 microM). The progesterone agonist R5020 was also very active (ID50 = 8 microM). This is the first report of a detailed examination of the steroid-induced inhibition of murine oocytes. A comparison between the results reported here and previous reports of steroid-induced inhibition in porcine oocytes reveals differences in the response of oocytes from the two families. The structure-activity relationships of the inhibitory steroids examined here suggest that the steroids are acting via a receptor-mediated system.


Assuntos
Meiose/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Progestinas/farmacologia , Animais , Técnicas de Cultura , Camundongos , Oócitos/citologia , Receptores de Esteroides/efeitos dos fármacos , Esteroides/farmacologia , Suínos
5.
J Biol Chem ; 267(7): 4408-15, 1992 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-1311309

RESUMO

S6 kinases I and II have been purified previously from Xenopus eggs and shown to be activated by phosphorylation on serine and threonine residues. An S6 kinase clone, closely related to S6 kinase II, was subsequently identified and the protein product was expressed in a baculovirus system. Using this protein, termed "rsk" for Ribosomal Protein S6 Kinase, as a substrate, we have purified to homogeneity from unfertilized Xenopus eggs a 41-kDa serine/threonine kinase termed rsk kinase. Both microtubule-associated protein-2 and myelin basic protein are good substrates for rsk kinase, whereas alpha-casein, histone H1, protamine, and phosvitin are not. rsk kinase is inhibited by low concentrations of heparin as well as by beta-glycerophosphate and calcium. Activation of rsk kinase during Xenopus oocyte maturation is correlated with phosphorylation on threonine and tyrosine residues. However, in vitro, rsk kinase undergoes autophosphorylation on serine, threonine, and tyrosine residues, identifying it as a "dual specificity" enzyme. Purified rsk kinase can be inactivated in vitro by either a 37-kDa T-cell protein-tyrosine phosphatase or the serine/threonine protein phosphatase 2A. Phosphatase-treated S6KII can be reactivated by rsk kinase, and S6 kinase activity in resting oocyte extracts increases significantly when purified rsk kinase is added. The availability of purified rsk kinase will enhance study of the signal transduction pathway(s) regulating phosphorylation of ribosomal protein S6 in Xenopus oocytes.


Assuntos
Isoenzimas/metabolismo , Proteínas Quinases/metabolismo , Serina/metabolismo , Treonina/metabolismo , Tirosina/metabolismo , Animais , Caseínas/metabolismo , Linhagem Celular , Cromatografia em Gel , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Ativação Enzimática , Feminino , Histonas/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação , Fosvitina/metabolismo , Protaminas/metabolismo , Inibidores de Proteínas Quinases , Proteínas Quinases/isolamento & purificação , Proteínas Quinases S6 Ribossômicas , Especificidade por Substrato , Xenopus
6.
J Am Vet Med Assoc ; 199(10): 1433-43, 1991 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-1666099

RESUMO

A new recombinant gp70 vaccine was found to be safe and effective for prevention of infection by FeLV. The vaccine incorporates a unique purified saponin adjuvant with the recombinant antigen. Serious systemic reactions were not observed during the efficacy trial. Local reactions were transient and mild. More than 2,000 doses were administered to a cross section of household cats in a field safety trial. Only 1 cat had hypersensitivity reaction, which resolved. Among veterinarians who used the vaccine and the cat owners, the vaccine was judged satisfactory and safe. After rigorous intraperitoneal challenge exposure without use of immunosuppressants, 100% of the controls in the efficacy trial became infected, 70% of which remained persistently infected with FeLV. Among vaccinates, 45% were never viremic and 40% cleared transient infection within 12 weeks after challenge exposure. Of the 20 vaccinated cats, 3 were persistently infected. Overall, 85% of cats vaccinated with this recombinant DNA FeLV vaccine resisted persistent FeLV infection after stringent challenge exposure, which translates to preventable fraction of 78.6%.


Assuntos
Vírus da Leucemia Felina/imunologia , Leucemia Felina/prevenção & controle , Proteínas Oncogênicas de Retroviridae , Vacinas Virais , Adjuvantes Imunológicos , Hidróxido de Alumínio/imunologia , Animais , Anticorpos Antivirais/biossíntese , Anticorpos Antivirais/sangue , Gatos , Feminino , Imunização Secundária/efeitos adversos , Imunização Secundária/veterinária , Injeções Subcutâneas/efeitos adversos , Injeções Subcutâneas/veterinária , Masculino , Proteínas Oncogênicas de Retroviridae/administração & dosagem , Proteínas Oncogênicas de Retroviridae/efeitos adversos , Proteínas Oncogênicas de Retroviridae/imunologia , Saponinas/imunologia , Vacinação/efeitos adversos , Vacinação/veterinária , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/efeitos adversos , Vacinas Virais/imunologia , Viremia/prevenção & controle , Viremia/veterinária
7.
Mol Cell Biol ; 10(1): 310-5, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2152963

RESUMO

Treatment with insulin or progesterone or microinjection of the transforming protein product of Ha-rasVal-12,Thr-59 (p21) is known to induce germinal vesicle breakdown in Xenopus oocytes. We have investigated the effect of p21 on S6 kinase and the H1 histone kinase of maturation-promoting factor in the presence and absence of antisense oligonucleotides against the c-mosxe proto-oncogene. Injection of p21 led to a rapid increase in S6 phosphorylation, with kinetics similar to those previously observed with insulin. Microinjection of c-mosxe antisense oligonucleotides inhibited germinal vesicle breakdown induced by p21 and totally abolished S6 kinase activation by insulin or progesterone but only partially inhibited activation by p21. However, the activation of p34cdc2 protein kinase by all three stimuli was blocked by antisense oligonucleotides. The results suggest that in oocyte maturation c-mosxe functions downstream of p21 but upstream of p34cdc2 and S6 kinase activation, although not all p21-induced events require c-mosxe.


Assuntos
Substâncias de Crescimento/metabolismo , Proteína Oncogênica p21(ras)/fisiologia , Oócitos/fisiologia , Protamina Quinase/metabolismo , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Ribossômicas/metabolismo , Animais , Ativação Enzimática , Insulina/farmacologia , Fator Promotor de Maturação , Oligonucleotídeos , Oligonucleotídeos Antissenso , Progesterona/farmacologia , Proteínas Proto-Oncogênicas c-mos , Proteína S6 Ribossômica , Proteínas Quinases S6 Ribossômicas , Xenopus laevis
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