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1.
J Med Chem ; 66(8): 5907-5936, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37017629

RESUMO

CCT251236 1, a potent chemical probe, was previously developed from a cell-based phenotypic high-throughput screen (HTS) to discover inhibitors of transcription mediated by HSF1, a transcription factor that supports malignancy. Owing to its activity against models of refractory human ovarian cancer, 1 was progressed into lead optimization. The reduction of P-glycoprotein efflux became a focus of early compound optimization; central ring halogen substitution was demonstrated by matched molecular pair analysis to be an effective strategy to mitigate this liability. Further multiparameter optimization led to the design of the clinical candidate, CCT361814/NXP800 22, a potent and orally bioavailable fluorobisamide, which caused tumor regression in a human ovarian adenocarcinoma xenograft model with on-pathway biomarker modulation and a clean in vitro safety profile. Following its favorable dose prediction to human, 22 has now progressed to phase 1 clinical trial as a potential future treatment for refractory ovarian cancer and other malignancies.


Assuntos
Antineoplásicos , Neoplasias Ovarianas , Humanos , Feminino , Fatores de Transcrição/metabolismo , Neoplasias Ovarianas/patologia , Linhagem Celular Tumoral , Antineoplásicos/farmacologia
2.
J Med Chem ; 66(4): 2918-2945, 2023 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-36727211

RESUMO

Herein, we report the optimization of a meta-substituted series of selective estrogen receptor degrader (SERD) antagonists for the treatment of ER+ breast cancer. Structure-based design together with the use of modeling and NMR to favor the bioactive conformation led to a highly potent series of basic SERDs with promising physicochemical properties. Issues with hERG activity resulted in a strategy of zwitterion formation and ultimately in the identification of 38. This compound was shown to be a highly potent SERD capable of effectively degrading ERα in both MCF-7 and CAMA-1 cell lines. The low lipophilicity and zwitterionic nature led to a SERD with a clean secondary pharmacology profile and no hERG activity. Favorable physicochemical properties resulted in good oral bioavailability in preclinical species and potent in vivo activity in a mouse xenograft model.


Assuntos
Neoplasias da Mama , Receptores de Estrogênio , Camundongos , Humanos , Animais , Feminino , Receptores de Estrogênio/metabolismo , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Antagonistas de Estrogênios/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Receptor alfa de Estrogênio/metabolismo , Linhagem Celular
3.
Fertil Steril ; 116(1): 2-3, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34148585

RESUMO

The in vitro fertilization and andrology laboratories are at the center of assisted reproductive technologies and the place where technicians and embryologists manipulate gametes and preimplantation-stage embryos with the goal of achieving the best embryo for transfer. Through the years, these laboratories have seen developments in technique, technology, and testing. The goal of this Views and Interviews series is to bring together the thought leaders in the field and envision what the laboratories will look like in the next 10 years.


Assuntos
Andrologia/tendências , Serviços de Laboratório Clínico/tendências , Fertilização in vitro/tendências , Infertilidade/terapia , Medicina Reprodutiva/tendências , Difusão de Inovações , Feminino , Previsões , História do Século XXI , Humanos , Infertilidade/diagnóstico , Infertilidade/fisiopatologia , Masculino , Gravidez
4.
Fertil Steril ; 116(1): 4-12, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34148588

RESUMO

The aim of this article is to gather 9 thought leaders and their team members to present their ideas about the future of in vitro fertilization and the andrology laboratory. Although we have seen much progress and innovation in the laboratory over the years, there is still much to come, and this article looks at what these leaders think will be important in the future development of technology and processes in the laboratory.


Assuntos
Andrologia/tendências , Serviços de Laboratório Clínico/tendências , Fertilização in vitro/tendências , Infertilidade/terapia , Medicina Reprodutiva/tendências , Andrologia/legislação & jurisprudência , Automação Laboratorial , Serviços de Laboratório Clínico/legislação & jurisprudência , Difusão de Inovações , Feminino , Fertilização in vitro/legislação & jurisprudência , Previsões , História do Século XXI , Humanos , Infertilidade/diagnóstico , Infertilidade/fisiopatologia , Masculino , Formulação de Políticas , Gravidez , Medicina Reprodutiva/legislação & jurisprudência
5.
ACS Med Chem Lett ; 11(12): 2519-2525, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33335676

RESUMO

Herein we describe our efforts using a late stage functionalization together with more traditional synthetic approaches to generate fluorinated analogues of the clinical candidate AZD9833. The effects of the addition of fluorine on the lipophilicity, permeability, and metabolism are discussed. Many of these changes were tolerated in terms of pharmacology and resulted in high quality molecules which reached advanced stages of profiling in the testing cascade.

6.
Bioorg Med Chem ; 28(23): 115815, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33091850

RESUMO

In this article, we report our efforts towards improving in vitro human clearance in a series of 5-azaquinazolines through a series of C4 truncations and C2 expansions. Extensive DMPK studies enabled us to tackle high Aldehyde Oxidase (AO) metabolism and unexpected discrepancies in human hepatocyte and liver microsomal intrinsic clearance. Our efforts culminated with the discovery of 5-azaquinazoline 35, which also displayed exquisite selectivity for IRAK4, and showed synergistic in vitro activity against MyD88/CD79 double mutant ABC-DLBCL in combination with the covalent BTK inhibitor acalabrutinib.


Assuntos
Quinases Associadas a Receptores de Interleucina-1/antagonistas & inibidores , Inibidores de Proteínas Quinases/metabolismo , Quinazolinas/química , Aldeído Oxidase/metabolismo , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cristalografia por Raios X , Cães , Estabilidade de Medicamentos , Meia-Vida , Hepatócitos/metabolismo , Humanos , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Camundongos , Microssomos Hepáticos/metabolismo , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/metabolismo , Quinazolinas/farmacologia , Ratos , Relação Estrutura-Atividade
7.
J Med Chem ; 63(23): 14530-14559, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-32910656

RESUMO

Herein we report the optimization of a series of tricyclic indazoles as selective estrogen receptor degraders (SERD) and antagonists for the treatment of ER+ breast cancer. Structure based design together with systematic investigation of each region of the molecular architecture led to the identification of N-[1-(3-fluoropropyl)azetidin-3-yl]-6-[(6S,8R)-8-methyl-7-(2,2,2-trifluoroethyl)-6,7,8,9-tetrahydro-3H-pyrazolo[4,3-f]isoquinolin-6-yl]pyridin-3-amine (28). This compound was demonstrated to be a highly potent SERD that showed a pharmacological profile comparable to fulvestrant in its ability to degrade ERα in both MCF-7 and CAMA-1 cell lines. A stringent control of lipophilicity ensured that 28 had favorable physicochemical and preclinical pharmacokinetic properties for oral administration. This, combined with demonstration of potent in vivo activity in mouse xenograft models, resulted in progression of this compound, also known as AZD9833, into clinical trials.


Assuntos
Antineoplásicos/administração & dosagem , Moduladores Seletivos de Receptor Estrogênico/administração & dosagem , Administração Oral , Antineoplásicos/química , Antineoplásicos/farmacocinética , Disponibilidade Biológica , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Ciclização , Descoberta de Drogas , Feminino , Humanos , Lipídeos/química , Estrutura Molecular , Moduladores Seletivos de Receptor Estrogênico/química , Moduladores Seletivos de Receptor Estrogênico/farmacocinética , Relação Estrutura-Atividade
8.
Reprod Biomed Online ; 38(5): 711-723, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30922557

RESUMO

RESEARCH QUESTION: How does oocyte cohort size affect IVF treatment outcomes? DESIGN: Retrospective cohort analysis of 10,193 fresh autologous oocyte retrievals among good-prognosis patients <35 years from 2009 to 2015. The primary outcome was live birth from a fresh transfer; secondary outcomes included cumulative live birth potential from the retrieved cohort and frequency of severe ovarian hyperstimulation syndrome (OHSS). RESULTS: Live birth per fresh transfer increased as the oocyte cohort increased up to 11-15 oocytes, then plateaued. Beyond 15 oocytes, live birth rates from fresh transfer did not decrease, even at the highest oocyte yields. When accounting for the availability of cryopreserved high-quality supernumerary blastocysts, the cumulative number of potential live births per retrieval continued to increase as oocyte yield increased. Rates of severe OHSS increased rapidly with increasing cohort size above 7-10 oocytes when final oocyte maturation was triggered with human chorionic gonadotrophin (HCG), up to nearly 7% of HCG-triggered retrievals of >25 oocytes, but when triggered with gonadotrophin-releasing hormone (GnRH) agonist the severe OHSS rate remained relatively low and stable at approximately 1% even among retrievals of the largest oocyte cohorts. CONCLUSIONS: Live birth rates per fresh embryo transfer are highest among cycles with retrieval of 11 or more oocytes. Larger cohorts are not associated with any decline in fresh transfer birth rates. Total potential births per retrieval continue to increase as the number of retrieved oocytes increases. Rates of OHSS remain relatively low after retrieval of large oocyte cohorts if final maturation is triggered with GnRH agonist rather than HCG.


Assuntos
Fertilização in vitro/estatística & dados numéricos , Recuperação de Oócitos/estatística & dados numéricos , Taxa de Gravidez , Adulto , Blastocisto , Criopreservação , Feminino , Humanos , Síndrome de Hiperestimulação Ovariana/etiologia , Indução da Ovulação/efeitos adversos , Gravidez , Estudos Retrospectivos
9.
ACS Med Chem Lett ; 9(12): 1199-1204, 2018 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-30613326

RESUMO

Polypharmacology is often a key contributor to the efficacy of a drug, but is also a potential risk. We investigated two hits discovered via a cell-based phenotypic screen, the CDK9 inhibitor CCT250006 (1) and the pirin ligand CCT245232 (2), to establish methodology to elucidate their secondary protein targets. Using computational pocket-based analysis, we discovered intrafamily polypharmacology for our kinase inhibitor, despite little overall sequence identity. The interfamily polypharmacology of 2 with B-Raf was used to discover a novel pirin ligand from a very small but privileged compound library despite no apparent ligand or binding site similarity. Our data demonstrates that in areas of drug discovery where intrafamily polypharmacology is often an issue, ligand dissimilarity cannot necessarily be used to assume different off-target profiles and that understanding interfamily polypharmacology will be important in the future to reduce the risk of idiopathic toxicity and in the design of screening libraries.

10.
Angew Chem Int Ed Engl ; 56(47): 14883-14887, 2017 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-28926175

RESUMO

Catalytic oxidative cyclisation reactions have been employed for the synthesis of the E and F rings of the complex natural product target pectenotoxin 4. The choice of metal catalyst (cobalt- or osmium-based) allowed for the formation of THF rings with either trans or cis stereoselectivity. Fragment union using a modified Julia reaction then enabled the synthesis of an advanced synthetic intermediate containing the EF and G rings of the target.

11.
J Med Chem ; 60(1): 180-201, 2017 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-28004573

RESUMO

Phenotypic screens, which focus on measuring and quantifying discrete cellular changes rather than affinity for individual recombinant proteins, have recently attracted renewed interest as an efficient strategy for drug discovery. In this article, we describe the discovery of a new chemical probe, bisamide (CCT251236), identified using an unbiased phenotypic screen to detect inhibitors of the HSF1 stress pathway. The chemical probe is orally bioavailable and displays efficacy in a human ovarian carcinoma xenograft model. By developing cell-based SAR and using chemical proteomics, we identified pirin as a high affinity molecular target, which was confirmed by SPR and crystallography.


Assuntos
Amidas/química , Proteínas de Transporte/química , Proteínas de Ligação a DNA/química , Proteínas Nucleares/química , Quinolinas/química , Fatores de Transcrição/química , Administração Oral , Amidas/administração & dosagem , Amidas/farmacologia , Disponibilidade Biológica , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Dioxigenases , Descoberta de Drogas , Fatores de Transcrição de Choque Térmico , Ligantes , Espectroscopia de Prótons por Ressonância Magnética , Quinolinas/administração & dosagem , Quinolinas/farmacologia , Espectrometria de Massas por Ionização por Electrospray
12.
Fertil Steril ; 106(2): 354-362.e2, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27172399

RESUMO

OBJECTIVE: To evaluate factors associated with cryopreserved blastocyst transfer birth outcomes, including age, expansion time, cryopreservation protocol, cryodamage, and number of embryos transferred. DESIGN: Retrospective cohort study. SETTING: Private infertility practice. PATIENT(S): Cryopreserved blastocyst transfer patients from January 2003 to April 2012. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Birth per transfer and children per embryo. RESULT(S): Overall live birth per transfer was 32%, with 17% twin births and 0.3% triplets. Live birth per transfer was significantly higher for vitrification compared with slow-freeze (day 5 cryopreservation: 47% vs. 35%; day 6 cryopreservation: 46% vs. 24%), as was live born children per transferred embryo (39% vs. 29% for day 5; 36% vs. 18% for day 6). Birth rates declined only slightly with increasing age at cryopreservation through 37 years, followed by an increasingly rapid decline in success with increasing age thereafter. Live birth rates declined rapidly (49%-18% for vitrification and 37%-10% for slow-freeze) as the percentage of intact cells after cryopreservation decreased from 95%-100% to 70%-79%, with almost no births when the percentage of intact cells was <70%. Increasing numbers of embryos per transfer were associated with significant increase in live birth per transfer but significant decrease in children per transferred embryo. Birth rates were much lower for blastocysts with delayed expansion on day 7 (10% per transfer). CONCLUSION(S): Birth outcomes from cryopreserved blastocyst transfer are influenced by age, timing of expansion, cryopreservation protocol, visible cryodamage, and the number of embryos transferred. Vitrification substantially improves outcomes versus slow freezing.


Assuntos
Blastômeros/fisiologia , Criopreservação , Transferência Embrionária , Infertilidade/terapia , Criopreservação/métodos , Implantação do Embrião , Transferência Embrionária/efeitos adversos , Transferência Embrionária/métodos , Feminino , Fertilidade , Fertilização in vitro , Humanos , Infertilidade/diagnóstico , Infertilidade/fisiopatologia , Gravidez , Taxa de Gravidez , Gravidez de Trigêmeos , Gravidez de Gêmeos , Estudos Retrospectivos , Fatores de Risco , Transferência de Embrião Único , Fatores de Tempo , Resultado do Tratamento
13.
Fertil Steril ; 105(2): 459-66.e2, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26604065

RESUMO

OBJECTIVE: To evaluate a single treatment center's experience with autologous IVF using vitrified and warmed oocytes, including fertilization, embryonic development, pregnancy, and birth outcomes, and to estimate the likelihood of live birth of at least one, two, or three children according to the number of mature oocytes cryopreserved by elective fertility preservation patients. DESIGN: Retrospective cohort study. SETTING: Private practice clinic. PATIENT(S): Women undergoing autologous IVF treatment using vitrified and warmed oocytes. Indications for oocyte vitrification included elective fertility preservation, desire to limit the number of oocytes inseminated and embryos created, and lack of available sperm on the day of oocyte retrieval. INTERVENTION(S): Oocyte vitrification, warming, and subsequent IVF treatment. MAIN OUTCOME MEASURE(S): Post-warming survival, fertilization, implantation, clinical pregnancy, and live birth rates. RESULT(S): A total of 1,283 vitrified oocytes were warmed for 128 autologous IVF treatment cycles. Postthaw survival, fertilization, implantation, and birth rates were all comparable for the different oocyte cryopreservation indications; fertilization rates were also comparable to fresh autologous intracytoplasmic sperm injection cycles (70% vs. 72%). Implantation rates per embryo transferred (43% vs. 35%) and clinical pregnancy rates per transfer (57% vs. 44%) were significantly higher with vitrified-warmed compared with fresh oocytes. However, there was no statistically significant difference in live birth/ongoing pregnancy (39% vs. 35%). The overall vitrified-warmed oocyte to live born child efficiency was 6.4%. CONCLUSION(S): Treatment outcomes using autologous oocyte vitrification and warming are as good as cycles using fresh oocytes. These results are especially reassuring for infertile patients who must cryopreserve oocytes owing to unavailability of sperm or who wish to limit the number of oocytes inseminated. Age-associated estimates of oocyte to live-born child efficiencies are particularly useful in providing more explicit expectations regarding potential births for elective oocyte cryopreservation.


Assuntos
Criopreservação , Preservação da Fertilidade/métodos , Fertilização in vitro , Recuperação de Oócitos , Oócitos , Vitrificação , Adulto , Fatores Etários , Transferência Embrionária , Feminino , Fertilização in vitro/efeitos adversos , Humanos , Nascido Vivo , Recuperação de Oócitos/efeitos adversos , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
14.
Fertil Steril ; 99(5): 1283-1289.e1, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23312233

RESUMO

OBJECTIVE: To estimate the effect of the embryo stage, trophectoderm (TE) morphology grade, and inner cell mass (ICM) morphology grade on live birth in single-blastocyst transfers. DESIGN: Retrospective cohort study. SETTING: Large private assisted reproductive technologies (ART) practice. PATIENT(S): Fresh autologous ART cycles. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Live birth. RESULT(S): A total of 694 single-blastocyst transfers met the inclusion criteria. Univariate regression analysis showed embryo stage and TE score to be correlated with implantation and live birth. Live birth rates were 57%, 40%, and 25% for TE grades A, B, and C, respectively. There was no significant association between ICM grade and implantation or live birth. Live birth rates were 53%, 52%, and 0% for ICM grades A, B, and C respectively. Multiple logistic regression analysis showed that only patient age and TE grade were significantly associated with implantation and live birth, whereas ICM grade was not significantly associated with outcome. The TE score had the strongest correlation with live birth. CONCLUSION(S): TE grading, but not ICM grading, significantly correlated with implantation and live birth for single-blastocyst transfers.


Assuntos
Aborto Espontâneo/diagnóstico , Massa Celular Interna do Blastocisto/citologia , Técnicas de Cultura Embrionária/métodos , Fertilização in vitro/métodos , Taxa de Gravidez , Transferência de Embrião Único/métodos , Aborto Espontâneo/epidemiologia , Massa Celular Interna do Blastocisto/fisiologia , Técnicas de Cultura Embrionária/estatística & dados numéricos , Implantação do Embrião , Desenvolvimento Embrionário/fisiologia , Feminino , Humanos , Valor Preditivo dos Testes , Gravidez , Estudos Retrospectivos , Fatores de Risco , Transferência de Embrião Único/estatística & dados numéricos
15.
Chem Commun (Camb) ; 47(20): 5849-51, 2011 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-21503291

RESUMO

A synthetic method for conducting the acyloin reaction using electron transfer in solution is reported. By linking two esters via their oxygen atoms, it was possible to perform crossed acyloin reactions between two different ester functionalities and display a high degree of preference for an intramolecular coupling process.


Assuntos
Álcoois Graxos/química , Transporte de Elétrons , Ésteres , Lítio/química , Estereoisomerismo
16.
Fertil Steril ; 87(2): 283-7, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17094975

RESUMO

OBJECTIVE: To evaluate whether assisted hatching improves clinical outcomes of embryo transfers to good prognosis patients, defined as patients < or =39 years with normal follicle-stimulating hormone (FSH) and E(2) levels, no more than one previous unsuccessful cycle of in vitro fertilization (IVF)-embryo transfer, and good embryo quality. DESIGN: Prospective randomized controlled trial. SETTING: Private assisted reproductive technology (ART) center. PATIENT(S): One hundred ninety-nine good prognosis patients undergoing IVF-embryo transfer. INTERVENTION(S): In vitro fertilization followed by embryo transfer on day 3 after oocyte retrieval with or without assisted hatching using a 1,480-nm wavelength infrared laser. MAIN OUTCOME MEASURE(S): Clinical intrauterine pregnancy, spontaneous pregnancy loss, and live birth. RESULT(S): Rates of clinical intrauterine pregnancy with fetal cardiac activity (53% vs. 54% per cycle), spontaneous pregnancy loss (13% vs. 16% per pregnancy), and live birth (47% vs. 46% per cycle) were very similar between treatment cycles with laser-assisted hatching and control cycles in which embryos were transferred without assisted hatching. There were no significant differences between treatment and control groups in any measured clinical outcome parameters. CONCLUSION(S): Assisted hatching does not improve clinical outcomes among good prognosis patients.


Assuntos
Transferência Embrionária/estatística & dados numéricos , Fertilização in vitro/estatística & dados numéricos , Infertilidade Feminina/epidemiologia , Infertilidade Feminina/terapia , Terapia a Laser , Microdissecção/estatística & dados numéricos , Resultado da Gravidez/epidemiologia , Adulto , Feminino , Humanos , Maryland/epidemiologia , Microdissecção/métodos , Micromanipulação/métodos , Micromanipulação/estatística & dados numéricos , Avaliação de Resultados em Cuidados de Saúde , Gravidez , Prognóstico , Resultado do Tratamento
17.
Fertil Steril ; 86(4): 862-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16935284

RESUMO

OBJECTIVE: To evaluate viability and implantation potential of cryopreserved blastocysts according to the day of blastocyst expansion and cryopreservation. DESIGN: Retrospective study. SETTING: Private ART center. PATIENT(S): Three hundred and seventy-five patients undergoing embryo transfer with cryopreserved blastocysts. INTERVENTION(S): Blastocyst cryopreservation on day 5, 6, or 7 after oocyte retrieval according to the day of blastocyst expansion and subsequent embryo transfer. MAIN OUTCOME MEASURE(S): Clinical pregnancy rate (PR) per embryo transfer. RESULT(S): Clinical PRs were similar between blastocysts cryopreserved on day 5 and blastocysts cryopreserved on day 6 (32% vs. 28%). The clinical PR was lower for blastocysts cryopreserved on day 7 (15%), but this difference was not statistically significant after accounting for the number of embryos per transfer (P=.15). CONCLUSION(S): Viability and implantation potential are similar for day 5 and day 6 blastocyst cryopreservation. Viability may be reduced for blastocysts cryopreserved on day 7, but not to the extent suggested by reports of fresh transfers. These results suggest that reduced success rates associated with fresh transfers of later developing blastocysts may be the result of asynchrony with endometrial receptivity instead of poorer embryo quality.


Assuntos
Criopreservação/métodos , Transferência Embrionária , Desenvolvimento Embrionário , Endométrio/citologia , Fertilização in vitro , Resultado da Gravidez , Injeções de Esperma Intracitoplásmicas , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Estudos Retrospectivos , Resultado do Tratamento
18.
J Exp Clin Assist Reprod ; 3: 5, 2006 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-16822317

RESUMO

BACKGROUND: Intracytoplasmic sperm injection (ICSI) is a component of infertility treatment often employed when conventional in vitro fertilization is unlikely to be successful. Despite good clinical results with ICSI, the procedure is typically associated with degeneration of a significant percentage (approximately 10%) of the treated oocytes. The cause of this degeneration remains unclear. Speculation that damage caused by oocyte compression during the injection procedure may be responsible has led to the development of a novel technique known as laser-assisted ICSI. This procedure involves drilling a small hole through the zona pellucida with a laser prior to sperm injection. Preliminary studies have suggested that laser-assisted ICSI may dramatically reduce oocyte degeneration rates. The objective of this study was to examine whether the reported benefits of laser-assisted ICSI could be verified on a larger, less-selected group of patients. METHODS: Oocytes retrieved from 59 patients scheduled for ICSI were randomly divided into equal treatment and control groups. Oocytes in the treatment group were inseminated by laser-assisted ICSI, while oocytes in the control group were inseminated by conventional ICSI. Outcome variables (oocyte fertilization and degeneration, embryo cell numbers and fragmentation on days 2 and 3, and compaction and blastocyst formation rates) were compared between treatment and control groups by paired-sample t-test. Subgroup analysis was performed according to zona pellucida and oolemma breakage patterns. RESULTS: No significant differences between treatment and control groups were observed for any of the measured outcome variables. However, fragile zonae pellucidae were associated with significantly poorer embryo quality, and fragile oolemmas that broke easily upon insertion of the injection needle were associated with a significantly higher oocyte degeneration rate. Nevertheless, there were also no between-treatment differences in clinical outcomes within these patient subpopulations. CONCLUSION: Contrary to previous reports based on smaller sample sizes, the results of this study suggest that there is no benefit of laser-assisted ICSI, either for the general population of ICSI patients, or for patients prone to zona pellucida or oolemma fragility.

19.
Fertil Steril ; 86(1): 20-6, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16762345

RESUMO

OBJECTIVE: To evaluate implantation of day 5 and day 6 vitrified and slow-frozen blastocysts. DESIGN: Retrospective analysis comparing two cryopreservation techniques. SETTING: Private IVF clinic. PATIENT(S): Five hundred eight cryopreserved embryo transfer candidates. INTERVENTION(S): Supernumerary day 5 and day 6 blastocysts were vitrified or slow-frozen and transfered after warming or thawing. MAIN OUTCOME MEASURE(S): Comparison of two cryopreservation techniques with respect to survival rate, implantation, and pregnancy rates of day 5 and day 6 blastocysts. RESULT(S): In 254 vitrified transfer cycles, survival, embryonic implantation, and clinical pregnancy rates for day 5 blastocysts were 95.9%, 33.4%, 48.7%, respectively, and for day 6 blastocysts 97.5%, 25.9%, 42.8%. In 254 slow-frozen transfer cycles, survival, embryonic implantation, and clinical pregnancy rates for day 5 blastocysts were 91.4%, 29.6%, 42.8%, respectively, and for day 6 blastocysts 94.8%, 28.2%, 43.1%. Overall there was a slightly, but not significantly, higher outcome regarding implantation and clinical pregnancy with the use of day 5 blastocysts (31.3% and 45.4%, respectively) versus day 6 blastocysts (26.7, and 42.9%, respectively). CONCLUSION(S): Vitrification technique yields the same implantation and pregnancy rate as slow-frozen blastocyst transfers. Slow growing embryos can be cryopreserved on day 6, because they yield a satisfactory survival, implantation, and pregnancy rate.


Assuntos
Blastocisto/citologia , Criopreservação/métodos , Criopreservação/estatística & dados numéricos , Transferência Embrionária/estatística & dados numéricos , Infertilidade Feminina/epidemiologia , Infertilidade Feminina/terapia , Taxa de Gravidez , Adulto , Blastocisto/fisiologia , Sobrevivência Celular , Feminino , Humanos , Infertilidade Feminina/patologia , Gravidez , Resultado do Tratamento , Estados Unidos
20.
Semin Reprod Med ; 23(4): 325-35, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16317621

RESUMO

During the last few years, cryopreservation has become a relevant addition to therapeutic concepts in reproductive medicine. New data and publications have made it difficult to maintain an overview of all of the new developments and their results. The focus of interest more recently, especially with the cryopreservation of human oocytes and human ovarian tissue, has been vitrification as an interesting alternative to slow freezing methods. Even though studies investigating the slow freezing of human mature oocytes have resulted in very different survival rates, it could be an option for donor oocyte programs, in the case of threatened ovarian loss or when there is an objection to embryo freezing. An optimal freezing protocol and later use of thawed human ovarian tissue is still a point of discussion. There are encouraging results regarding different kinds of autotransplantation, and recently the first birth after orthotopic autotransplantation of cryopreserved/thawed human ovarian tissue was described in the literature. Independent of any objections to cryopreservation in general, vitrification is a potential and effective alternative to conventional slow cryopreservation, especially for oocytes and embryos. Vitrification might be also be an option for human ovarian tissue; however this is only in its infancy and requires much additional investigation. Our article discusses new trends and results of actual studies regarding these issues.


Assuntos
Criopreservação/métodos , Crioprotetores/normas , Oócitos , Espermatozoides , Criopreservação/tendências , Feminino , Humanos , Masculino , Ovário , Gravidez
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