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1.
J Obstet Gynaecol Res ; 49(6): 1560-1570, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36959087

RESUMO

AIM: To examine the implantation potential of fragmented embryos that underwent morphokinetic evaluation in a time-lapse incubator. METHODS: A retrospective study analyzing 4210 Day 5 embryos which were incubated in a time-lapse incubator, between 2013 and 2019. Embryos with more than 5% fragmentation (379 embryos) were included in the study. Embryos selected using the general model and re-examined by our in-house model. Embryo fragmentation percentage was documented from the first cell-division (start fragmentation) to its maximal percentage (final fragmentation), and the ratio between them (fragmentation worsening). Data were analyzed with relation to embryo development, embryos transfer or freezing, clinical pregnancy, and live birth rates. RESULTS: Embryo fragmentation and morphokinetics were found to be independent variables for clinical pregnancy achievements. A higher fragmentation worsening was noted among discarded embryos compared to transferred or frozen embryos (p < 0.0001). Advanced maternal age had a significant negative effect on fragmentation (p < 0.001). Missed abortion rates were similar in fragmented embryos that implanted compared with the overall population. Live birth rates were comparable among embryos which were selected for transfer or freezing by their morphokinetics and had different severity of fragmentation. CONCLUSION: Our study shows that fragmented embryos have a potential to implant and therefore should be selected for transfer. Laboratories which do not use time-lapse incubators for embryo selection, should consider transferring fragmented embryos, since they have an acceptable chance for live birth. Calculation of fragmentation worsening may enhance our ability to predict embryo development. Further research with analysis of more fragmented embryo maybe beneficial. This study was approved by the local ethics committee No. 0010-19 CMC on April 18th, 2019.


Assuntos
Transferência Embrionária , Fertilização in vitro , Gravidez , Feminino , Humanos , Estudos Retrospectivos , Taxa de Gravidez , Imagem com Lapso de Tempo , Blastocisto , Implantação do Embrião , Técnicas de Cultura Embrionária
2.
Arch Gynecol Obstet ; 306(4): 1245-1251, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35737126

RESUMO

PURPOSE: To compare efficacy of Intra Cytoplasmic Sperm Injection (ICSI) with conventional in vitro fertilization (IVF) on treatment outcome in women undergoing in vitro fertilization with donor sperm. METHODS: We examined retrospectively the outcome data from 203 patients undergoing fresh cycles of conventional IVF (cIVF) or ICSI and an additional 77 frozen-thawed embryo transfer (FET) cycles during 2003-2014, all using donor sperm. Fertilization, cleavage, pregnancy and live birth rates and number of high-quality embryos were compared between cIVF and ICSI. RESULTS: Altogether 185 women underwent 479 transfer cycles of fresh embryos (237 cIVF vs. 224 ICSI and 18 "rescue ICSI" cycles). In addition, 77 FET cycles were compared (24 cIVF vs. 53 ICSI cycles). No differences were found between cIVF and ICSI in fertilization, cleavage, pregnancy and live birth rates (92.6% vs 92.2%, 73.4% vs 72.4%, 25.3% vs 27.2% and 13.1% vs 14.7%, respectively). Pregnancy and life birth rates remained similar even when FET cycles were included (25.8% vs 26.2% and 13.1% vs 13.7%, respectively). The use of ICSI was associated with lower rates of high-quality embryos (52.7% vs. 63.3%, P < 0.0001). A multivariate logistic regression analysis found that patients' age, number of transferred embryos and smoking were independently associated with the chance to conceive. Patient age correlated inversely with fertilization rate (r = - 0.13, P < 0.006).Non-smokers were more likely to become pregnant (OR = 2.23, P < 0.012). CONCLUSIONS: Our results show that ICSI does not bypass the age-related decrease in oocyte quality in patients using donor sperm for IVF. Use of ICSI was associated with lower rates of high-quality embryos. The findings imply that ICSI should not be the primary method of insemination in patients undergoing IVF with donor sperm.


Assuntos
Fertilização in vitro , Injeções de Esperma Intracitoplásmicas , Feminino , Fertilização in vitro/métodos , Humanos , Inseminação , Masculino , Gravidez , Estudos Retrospectivos , Sêmen , Doadores de Tecidos
3.
Reprod Biol ; 21(4): 100565, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34600346

RESUMO

In certain patients cleavage stage embryos may be preferred. The relationship between an additional day in culture and pregnancy outcomes is not well established. We aimed to compare outcomes of day 2 versus overnight day 3 frozen embryo transfer (FET). In this randomized controlled trial, patients with day 2 cryopreserved embryos were allocated to two groups. In group A embryos were transferred on day 2, the same day of thawing. In group B embryos were transferred one day after thawing, on day 3 after overnight incubation. Out of 410 patients eligible, 92 were recruited. Finally, 72 patients participated, 39 in group A and 33 in group B. No significant difference in implantation (11 % in group A and 14 % in group B, p = 0.81), clinical pregnancy (18 % in group A and 21 % in group B, p = 0.73) or live birth rates (13 % in group A and 18 % in group B, p = 0.53) was found. To conclude, no significant difference in reproductive outcomes was found when comparing patients with day 2 or overnight day 3 FET. Considering published data on blastocyst transfer, cleavage stage ET may still be a relevant option and the decision between day 2 or overnight day 3 ET depends on patients' and physicians' preference and recommendation.


Assuntos
Blastocisto , Criopreservação , Transferência Embrionária , Adulto , Coeficiente de Natalidade , Feminino , Humanos , Gravidez , Estudos Prospectivos , Fatores de Tempo
4.
F S Sci ; 2(2): 176-197, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-35559752

RESUMO

OBJECTIVE: To study whether a powerful, in-house, embryo-selection model can be developed for a specific in vitro fertilization (IVF) laboratory where embryos were already selected for transfer using general models. DESIGN: In total, 12,944 fertilized oocytes were incubated in an EmbryoScope (Vitrolife, Göteborg, Sweden) at our laboratory. Embryos were selected for transfer or freezing using general models. There were 1,879 embryos with known implantation data (KID), of which 425 had positive KIDs. For the outcome, we set 3 endpoints for KID's definition: gestational sac, clinical pregnancy, and live birth. Results of a comparison between KID-positive and -negative embryos for cell division timings were analyzed separately for intracytoplasmic sperm injection (ICSI) and IVF embryos in patients aged 18-41 years. SETTING: IVF center. PATIENTS: The study included 1,075 women undergoing IVF or ICSI treatment between June 2013 and February 2019. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The KID-positive and -negative embryos were analyzed for statistical differences in cell division timing and cell cycle intervals. We used the EmbryoScope Stats software (Unisense FertiliTech, Aarhus, Denmark) for model development. The statistically different timing parameters were tested for their contribution to scoring in the model. The algorithms were tested for area under the receiver operating characteristic curve (AUC) in the KID embryos for developing day-2, -3, and -5 embryo-selection models. The validation of these algorithms was performed using calibration/validation procedures. RESULTS: Because significant differences in morphokinetics were found between the KID-positive and KID-negative embryos in our laboratory, it was possible to use our specific KID data to develop an in-house model. The algorithms were developed for embryo selection on days 2, 3, and 5 in the ICSI embryos. In most cases, AUC was >0.65, which indicated that these models were valid in our laboratory. In addition, these AUC values were obtained from all gestational sac, clinical pregnancy, and live birth KID embryo databases tested. An increase in the predictability of the models was observed from days 2-3 to day 5 models. The AUC test results ranged between 0.657 and 0.673 for day 2 and day 3, respectively, and 0.803 for the day 5 model. CONCLUSION: A model based on laboratory-specific morphokinetics was found to be complementary to general models and an important additive tool for improving single embryo selection. Developing an in-house laboratory-specific model requires many stages of sorting and characterization. Many insights were drawn about the model developing process. These may facilitate and improve the process in other laboratories.


Assuntos
Transferência Embrionária , Laboratórios , Transferência Embrionária/métodos , Feminino , Fertilização in vitro , Humanos , Gravidez , Estudos Retrospectivos , Imagem com Lapso de Tempo/métodos
5.
Biochem Biophys Res Commun ; 493(1): 52-57, 2017 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-28923245

RESUMO

p105 plays dual roles in NF-κB signaling: it generates the active subunit p50 and in its precursor form inhibits NF-κB activation. p105 processing occurs under basal conditions and increases following signaling. IκB kinase ß (IKKß) mediates phosphorylation at the C-terminal domain of p105, leads to accelerated processing and degradation of the precursor. A20 is a dual function deubiquitinating and ubiquitin ligating enzyme, involving in turning-off the NF-κB signaling pathway. Here we show that A20 suppresses TNFα-induced proteolysis of p105. We demonstrate that A20 inhibits both the signal induced processing and the degradation of p105 upstream to IKK stimulation. In addition, A20 represses the constitutive processing of the precursor protein in IKK independent manner. Silencing of A20 in cells by siRNA, restores p105 processing and the generation of p50. Functional analysis of A20, shows that the ubiquitin ligase activity mediated by its zinc finger domain (ZF), is required for the basal processing inhibitory effect. Its N-terminal ovarian tumor (OTU) domain, however, is not obligatory. We show that A20 inhibits p50 generation in cells by reducing the ubiquitination of its precursor, p105. Co-immunoprecipitation experiments show that A20 is immunoprecipitated by p105 only in the presence of its recently identified ligase, KPC1. Our data propose an additional novel mechanism to explain the known NF-κB inhibitory effects of A20: by affecting p105 ubiquitination and subsequently its degradation and limited processing.


Assuntos
Regulação da Expressão Gênica/fisiologia , Subunidade p50 de NF-kappa B/metabolismo , Transdução de Sinais/fisiologia , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Ubiquitinação/fisiologia , Células HEK293 , Humanos
6.
Biochem Biophys Res Commun ; 482(1): 106-111, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27810359

RESUMO

Murine double minute-2 (Mdm2) is one of the E3-ligases of the androgen receptor besides being the major regulator of the p53 tumor suppressor. The testis-specific USP26 was demonstrated to regulate the androgen receptor. In the present study we examined possible association between the deubiquitinating enzyme - ubiquitin specific protease 26 (USP26), and the oncoprotein E3 ligase - (Mdm-2). We analyzed the half-life time of USP26 in HEK293 cells. In a cell-free system we asked whether USP26 can be ubiquitinated by HeLa extract. In co-transfection experiments we expressed Mdm2 along with different constructs of USP26 in order to examine possible regulation of Mdm2 by USP26. We found that USP26 binds to Mdm2 through its coiled-coiled C-terminal domain. USP26 deubiquitinates Mdm2 and stabilizes it. The physiological significance of the findings is still not fully understood. The interaction between USP26 and Mdm2, and the subsequent deubiquitination of Mdm2, serves, most probably to regulate Mdm2. Future therapeutic modalities that interfere with the association between USP26 and Mdm2 will be used to destabilize the ligase in malignancies where it is upregulated.


Assuntos
Cisteína Endopeptidases/metabolismo , Enzimas Desubiquitinantes/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Testículo/enzimologia , Ubiquitina/metabolismo , Sítios de Ligação , Ativação Enzimática , Células HEK293 , Humanos , Masculino , Especificidade de Órgãos/fisiologia , Ligação Proteica , Especificidade por Substrato
7.
J Assist Reprod Genet ; 33(6): 731-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26973335

RESUMO

PURPOSE: The present study evaluated the association between oxidative parameters in embryo cryopreservation medium and laboratory and clinical outcomes. METHODS: This prospective laboratory study was conducted in an IVF unit in a university-affiliated hospital with 91 IVF patients undergoing a frozen-thawed embryo transfer cycle. Following thawing, 50 µL of embryo cryopreservation medium was retrieved from each cryotube and tested by the thermochemiluminescence (TCL) assay. TCL amplitudes after 50 (H1), 150 (H2), and 280 s (H3) were recorded in counts per second (CPS) and the TCL ratio determined for comparison with implantation and pregnancy rates. RESULTS: A total of 194 embryos were transferred in 85 frozen-thaw cycles. Twenty-one pregnancies (24.7 %) occurred. Implantation and overall and clinical pregnancy rates were higher when the median TCL H1 amplitude was <32 CPS compared to ≥32 CPS (14.6 vs. 5.3 %, 37.5 vs. 17 %, 28.1 vs. 9.4 %, respectively). No pregnancies occurred when the H1 amplitude was ≥40 CPS. Logistic regression multivariate analysis found that only the median TCL H1 amplitude was associated with the occurrence of pregnancy (OR = 2.93, 95 % CI 1.065-8.08). The TCL ratio inversely correlated with the duration of embryo cryopreservation (r = -0.37). CONCLUSIONS: The results indicate that thawed embryos may express oxidative processes in the cryopreservation medium, and higher oxidative levels are associated with lower implantation rates. These findings may aid in the improved selection of frozen-thawed embryos for IVF.


Assuntos
Criopreservação , Estresse Oxidativo , Adulto , Biomarcadores/análise , Estudos de Coortes , Meios de Cultura/química , Técnicas de Cultura Embrionária , Implantação do Embrião , Transferência Embrionária , Feminino , Fertilização in vitro , Humanos , Modelos Logísticos , Medições Luminescentes , Pessoa de Meia-Idade , Gravidez , Taxa de Gravidez
8.
Reprod Biomed Online ; 32(3): 308-15, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26795496

RESUMO

This preliminary study examined a possible effect of long duration repeated hormonal stimulation on the endometrium using a molecular tool. The expression of the hormone stimulated, cell cycle regulators, p27 and its ligase S-phase kinase-interacting protein2 (Skp2), were assessed in 46 endometrial samples of patients who underwent repeated IVF cycles (3-21). Skp2 protein is usually undetectable in normal tissue and can be demonstrated only in rapidly dividing cells. Samples from non-stimulated, normal cycling women served as control group A. Samples of endometrial carcinoma served as control group B. In secretory endometrium, the expression of p27 was found to be lower and Skp2 higher in the study group compared with control group A. Moreover, in 25% of patients of the study group, Skp2 expression was significantly higher (P < 0.05) compared with control group A, reaching concentrations demonstrated in endometrial carcinoma. The findings of this study suggest that repeated hormone stimulation cycles may disrupt endometrial physiology, potentially towards abnormal proliferation. These changes in protein expression are described for the first time in IVF patients and should be further investigated.


Assuntos
Endométrio/efeitos dos fármacos , Indução da Ovulação , Proteínas Quinases Associadas a Fase S/metabolismo , Adulto , Inibidor de Quinase Dependente de Ciclina p27 , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Endométrio/metabolismo , Endométrio/patologia , Feminino , Hormônio Foliculoestimulante/efeitos adversos , Hormônio Foliculoestimulante/uso terapêutico , Humanos , Menotropinas/efeitos adversos , Menotropinas/uso terapêutico , Nafarelina/efeitos adversos , Nafarelina/uso terapêutico
9.
Harefuah ; 154(6): 350-5, 406, 2015 Jun.
Artigo em Hebraico | MEDLINE | ID: mdl-26281076

RESUMO

INTRODUCTION: Large numbers of retrieved oocytes are associated with higher chances of having cryopreservation of embryos. However, the process entailed exposes women to increased risk for ovarian hyperstimulation syndrome. Furthermore, mild ovary stimulation protocols are more patient-friendly and with less adverse effects. Only limited reports exist on the significance of the number of retrieved oocytes achieved in a single stimulation cycle. AIM: To investigate the optimal number of retrieved oocytes to achieve pregnancy and live birth. METHODS: This retrospective analysis included 1590 IVF cycles. Oocytes maturation, fertilization, cleavage, as well as pregnancy and live birth rates were analyzed according to the number of retrieved oocytes. RESULTS: Oocyte maturation, fertilization and cleavage rates were lower in cycles with more than 10 retrieved oocytes compared with other groups. Live birth rates were highest when the number of retrieved oocytes was 11-15. CONCLUSIONS: Retrieval of more than 15 oocytes was not associated with a significant increase in chances of conception and birth. DISCUSSION: The better oocyte quality with 10 or less oocytes retrieved could be the result of a possible interference with the natural selection, or the minimized exposure of growing follicles to the potentially negative effects of ovarian stimulation. Although the average number of available embryos was higher when more than 10 oocytes were retrieved, achievement of more than 15 oocytes did not improve IVF outcome in terms of pregnancy and delivery rates. SUMMARY: Analysis of 1590 IVF cycles including the frozen-thawed transfers shows that the best outcomes were achieved with an optimal number of 11-15 oocytes.


Assuntos
Fertilização in vitro/métodos , Oócitos/citologia , Indução da Ovulação/métodos , Injeções de Esperma Intracitoplásmicas/métodos , Adolescente , Adulto , Coeficiente de Natalidade , Criopreservação/estatística & dados numéricos , Feminino , Humanos , Nascido Vivo , Pessoa de Meia-Idade , Folículo Ovariano/crescimento & desenvolvimento , Síndrome de Hiperestimulação Ovariana/epidemiologia , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Adulto Jovem
10.
Reprod Biomed Online ; 31(3): 421-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26206279

RESUMO

Male infertility constitutes 30-40% of all infertility cases. Some studies have shown a continuous decline in semen quality since the beginning of the 20th century. One postulated contributing factor is radio frequency electromagnetic radiation emitted from cell phones. This study investigates an association between characteristics of cell phone usage and semen quality. Questionnaires accessing demographic data and characteristics of cell phone usage were completed by 106 men referred for semen analysis. Results were analysed according to WHO 2010 criteria. Talking for ≥1 h/day and during device charging were associated with higher rates of abnormal semen concentration (60.9% versus 35.7%, P < 0.04 and 66.7% versus 35.6%, P < 0.02, respectively). Among men who reported holding their phones ≤50 cm from the groin, a non-significantly higher rate of abnormal sperm concentration was found (47.1% versus 11.1%). Multivariate analysis revealed that talking while charging the device and smoking were risk factors for abnormal sperm concentration (OR = 4.13 [95% CI 1.28-13.3], P < 0.018 and OR = 3.04 [95% CI 1.14-8.13], P < 0.027, respectively). Our findings suggest that certain aspects of cell phone usage may bear adverse effects on sperm concentration. Investigation using large-scale studies is thus needed.


Assuntos
Telefone Celular , Infertilidade Masculina/etiologia , Ondas de Rádio/efeitos adversos , Espermatozoides/efeitos da radiação , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise do Sêmen , Contagem de Espermatozoides
11.
Harefuah ; 150(3): 255-9, 303, 2011 Mar.
Artigo em Hebraico | MEDLINE | ID: mdl-21574360

RESUMO

Reactive oxygen and nitrogen species constitute an inseparable part of aerobic life on earth. They have been known to science for about 90 years, but only during the last 50 years research in this field has expanded. Initially, scientists focused on the free radicals-induced damage to biological systems. Since the eighties, a new concept has emerged, namely, that alongside the oxidative stress-induced deleterious effect and its association with a variety of diseases, a certain threshold level of oxidation is essential to intracellular signaL transduction. Recently, some data has accumulated regarding the involvement of oxidative processes in various aspects of female reproduction, including ovarian function, fertilization, early development of the embryo and implantation. Nevertheless, there is still a long way before comprehensive and thorough understanding of their role, both at the molecular level and the expression in the clinical setup of fertility patients can be achieved. In this article, we shall address some molecular biochemical processes involved in the activity of free radicals, and review the present knowledge regarding their role in female fertility, including ovarian physiology, follicular and oocyte maturation, development of the early embryo and implantation, as well as their association with reproductive pathologies such as endometriosis, polycystic ovary disease and recurrent pregnancy loss.


Assuntos
Fertilidade/fisiologia , Oxirredução , Reprodução/fisiologia , Aborto Habitual/fisiopatologia , Feminino , Radicais Livres/metabolismo , Humanos , Infertilidade Feminina/fisiopatologia , Estresse Oxidativo , Gravidez , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia
12.
Fertil Steril ; 95(3): 979-84, 2011 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-21071019

RESUMO

OBJECTIVE: To examine whether the oxidative status of an individual embryo before transfer may predict chances of implantation. DESIGN: A prospective laboratory study. SETTING: An IVF unit in a university-affiliated hospital. PATIENT(S): One hundred thirty-three women undergoing IVF-ET treatment cycles. INTERVENTION(S): Before ET, 10 µL of embryo culture medium was retrieved individually from each embryo and the oxidative status assessed by the thermochemiluminescence (TCL) analyzer. MAIN OUTCOME MEASURE(S): The occurrence of pregnancy. Two parameters were recorded: the TCL amplitude after 50 seconds (H1) and the TCL ratio. These were compared with demographic, clinical, and laboratory parameters and treatment outcome. All data underwent statistical analysis. RESULT(S): Altogether 284 embryos were transferred in 133 ET cycles. Forty-one pregnancies occurred (31%). For embryos transferred after 72 hours (77 transfers), the highest H1 levels in each group of transferred embryos correlated with the occurrence of pregnancy. The combination of maximal intracohort H1 level <210 counts per second with a TCL ratio of ≤ 80% had a positive predictive value of 70.6% for the occurrence of pregnancy. CONCLUSION(S): The oxidative status of the early embryo in IVF is associated with the chances of implantation. Assessment of the oxidative status of embryos in culture media before transfer may serve as an applicable tool for improving embryo selection in light of the legal limitations of the number of transferred embryos allowed.


Assuntos
Blastocisto/metabolismo , Meios de Cultura/metabolismo , Técnicas de Cultura Embrionária/métodos , Fertilização in vitro/métodos , Estresse Oxidativo/fisiologia , Taxa de Gravidez , Transferência Embrionária/métodos , Desenvolvimento Embrionário/fisiologia , Feminino , Humanos , Luminescência , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos
13.
Biochem Biophys Res Commun ; 389(2): 205-10, 2009 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-19695220

RESUMO

p105 plays dual roles in NF-kappaB signaling: in its precursor form it inhibits NF-kappaB activation, but limited processing by the ubiquitin system generates the p50 active subunit of the transcription factor. Here we show that ABIN-1, an A20-binding protein that is also known to attenuate NF-kappaB activation, inhibits p105 processing. p105 and ABIN-1 physically interact with one another, but the binding is not necessary for inhibition of processing. Rather, it appears to stabilize ABIN-1 and to increase its level, which further augments its inhibitory effect. Deletion of the processing inhibitory domain (PID) of p105 abrogates the inhibition which also requires the ABIN homology domain (AHD)-2 of ABIN-1. Together, the effects of ABIN-1 on p105 processing and of p105 on stabilizing ABIN-1 act to potentiate the NF-kappaB inhibitory activity of ABIN-1.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Subunidade p50 de NF-kappa B/antagonistas & inibidores , Linhagem Celular , Humanos , Subunidade p50 de NF-kappa B/genética , Estrutura Terciária de Proteína/genética , Deleção de Sequência
14.
J Urol ; 176(5): 2285-9, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17070313

RESUMO

PURPOSE: Loss of the cell cycle inhibitory protein p27Kip1 in cancer is associated with tumor aggressiveness and poor prognosis in the prostate. The decrease in p27(Kip1) results from increased proteasome dependent degradation, which is mediated by its specific ubiquitin ligase subunits S-phase kinase protein 2 and cyclin dependent kinase subunit 1. S-phase kinase protein 2 was found to be over expressed in aggressive prostate cancers but to our knowledge the role of cyclin dependent kinase subunit 1 in these cancers is unknown. MATERIALS AND METHODS: The expression of cyclin dependent kinase subunit 1, S-phase kinase protein 2 and p27Kip1 was examined by immunohistochemistry in tissue sections from 45 patients with prostate cancer. The expression of cyclin dependent kinase subunit 1 was compared to that of S-phase kinase protein 2 and p27Kip1, and patient clinical and histological characteristics. RESULTS: Cyclin dependent kinase subunit 1 expression was strongly associated with S-phase kinase protein 2 expression (r = 0.666, p = 0.001) and inversely with p27Kip1 expression (r = -0.737, p < 0.001). Cyclin dependent kinase subunit 1 over expression was associated with loss of tumor differentiation (r = 0.631, p = 0.001), high serum prostate specific antigen (r = 0.627, p < 0.001) and metastatic disease (p < 0.001). CONCLUSIONS: These results suggest that cyclin dependent kinase subunit 1 is involved in p27Kip1 down-regulation and it may have an important causative role in the development of aggressive tumor behavior in prostate cancer.


Assuntos
Proteínas de Transporte/fisiologia , Inibidor de Quinase Dependente de Ciclina p27/fisiologia , Quinases Ciclina-Dependentes/fisiologia , Neoplasias da Próstata/enzimologia , Proteínas Quinases Associadas a Fase S/fisiologia , Idoso , Idoso de 80 Anos ou mais , Quinases relacionadas a CDC2 e CDC28 , Humanos , Masculino , Pessoa de Meia-Idade
15.
Biochem Biophys Res Commun ; 345(1): 7-13, 2006 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-16678126

RESUMO

Generation of the p50 subunit of NF-kappaB is a rare case in which the ubiquitin system processes a longer precursor, p105, into a shorter active subunit: in the vast majority of cases, the target protein is completely degraded. The mechanisms involved in this process have remained elusive. It appears that a Gly rich region (GRR) in the middle of the molecule serves as a "processing stop signal", though under certain conditions, such as after stimulation, p105 can be completely degraded. Since NF-kappaB plays critical roles in a broad array of basic cellular processes, it is important to dissect the mechanisms that regulate its proteolysis-both destruction and processing. We have previously shown that signal-induced degradation of p105 requires ubiquitination on multiple lysines. Here we describe a novel region, a Processing Inhibitory Domain-PID, that upon its removal, the molecule is processed in high efficiency, which requires ubiquitination on a single, though non-specific, lysine.


Assuntos
Rim/metabolismo , Subunidade p50 de NF-kappa B/metabolismo , Peptídeo Hidrolases/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Transdução de Sinais/fisiologia , Ubiquitina/metabolismo , Linhagem Celular , Células HeLa , Humanos , Complexos Multienzimáticos/metabolismo
16.
Fertil Steril ; 82 Suppl 3: 1029-35, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15474069

RESUMO

OBJECTIVE: To examine matrix metalloproteinase-3 (MMP-3) expression in human stromal cell culture after P stimulation and the effect of conditioned medium from human embryo-epithelial cells coculture on its expression and activity. DESIGN: Metabolic and endocrine studies on human tissue. SETTING: In vitro fertilization (i.v.f.) unit and endocrine research unit. PATIENT(S): Infertile patients undergoing endometrial tissue sampling for dating at the luteal phase before i.v.f. INTERVENTION(S): Endometrial sampling and collection of human embryos culture media. MAIN OUTCOME MEASURE(S): Expression and activity of secreted MMP-3 by P-induced stromal cells, and in stromal cells exposed to conditioned medium from embryo-epithelial cell coculture. RESULT(S): Expression and activity of MMP-3 in human stromal cells decrease after P induction. Following incubation of these stromal-derived decidual cells with conditioned medium from embryo-epithelial cell coculture, MMP-3 expression and activity increased in a statistically significant manner. CONCLUSION(S): Progesterone inhibition of MMP-3 expression and its support of endometrial integrity were prevented by local expression of MMP-3 in response to embryonic signaling.


Assuntos
Embrião de Mamíferos/fisiologia , Endométrio/fisiologia , Metaloproteinase 3 da Matriz/metabolismo , Transdução de Sinais/fisiologia , Adulto , Blastocisto/enzimologia , Diferenciação Celular , Técnicas de Cocultura , Meios de Cultivo Condicionados/farmacologia , Técnicas de Cultura , Decídua/citologia , Decídua/efeitos dos fármacos , Decídua/enzimologia , Desenvolvimento Embrionário , Endométrio/citologia , Feminino , Humanos , Inibidores de Metaloproteinases de Matriz , Mórula/enzimologia , Progesterona/farmacologia , Células Estromais/citologia , Fatores de Tempo
17.
Fertil Steril ; 82 Suppl 3: 1171-6, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15474091

RESUMO

OBJECTIVE: To evaluate oxidative stress indices in follicular fluid (FF) by a novel thermochemiluminescence (TCL) assay and investigate the correlation between TCL and i.v.f. cycle parameters. DESIGN: Prospective, cross-sectional study. SETTING: I.v.f. Unit of an Obstetrics and Gynecology Department in a university-affiliated hospital. PATIENT(S): One hundred eighty-nine women undergoing consecutive i.v.f. treatment cycles during 2001. INTERVENTION(S): After oocyte retrieval, pooled FF was centrifuged and the supernatant was tested in the TCL assay. MAIN OUTCOME MEASURE(S): Maximal serum E2 levels, number of gonadotropin ampoules, retrieved oocytes, mature oocytes, fertilization and cleavage rates, number of available embryos and cryopreserved embryos, and clinical pregnancy rates and correlation with TCL indices. RESULT(S): The TCL curve slope of FF positively correlated with maximal serum E2 levels, number of mature oocytes, and number of cleaved embryos and was inversely correlated with the women's ages and the number of gonadotropin ampoules. Follicular fluid TCL amplitude at 50 seconds ranged from 294 to 711 cps, but all pregnancies (n = 50; 28.1%) occurred within the range of 347-569 cps. With 385 and 569 cps as cutoff levels for the occurrence of pregnancy, the negative predictive value beyond this range was 96% and the positive predictive value within this range was 32%. CONCLUSION(S): The TCL results may reflect the age-related increase in free radical activity and is associated with parameters of ovarian responsiveness and IVF outcome. A certain threshold of oxidative stress may be required for the occurrence of conception in i.v.f. TCL is a potential tool to evaluate, treat, and monitor antioxidant therapy in i.v.f. treatments.


Assuntos
Fertilização in vitro , Líquido Folicular/metabolismo , Temperatura Alta , Medições Luminescentes , Estresse Oxidativo , Taxa de Gravidez , Adulto , Envelhecimento , Estudos Transversais , Feminino , Humanos , Valor Preditivo dos Testes , Gravidez , Estudos Prospectivos
18.
Fertil Steril ; 81 Suppl 1: 792-7, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15019811

RESUMO

OBJECTIVE: To examine the effect of oxidation of proteins and lipids, as measured by a novel thermochemiluminescence (TCL) analyzer, and to evaluate the correlation between TCL indices in seminal plasma and sperm parameters. DESIGN: Experimental and prospective clinical studies. SETTING: An infertility unit. PATIENT(S): One hundred forty-eight men undergoing semen analysis. INTERVENTION(S): Bovine serum albumin (BSA) and linolenic acid were oxidized and tested by TCL, protein carbonyls, and conjugated dienes assays. All participants underwent semen analysis. Seminal plasma was tested by TCL and conjugated dienes. MAIN OUTCOME MEASURE(S): Thermochemiluminescence indices before and after oxidation of BSA and linolenic acid, compared with protein carbonyl and conjugated dienes indices. Correlation between semen parameters and TCL and conjugated dienes indices in seminal plasma. RESULT(S): Oxidation of BSA and linolenic acid was marked by characteristic changes in their TCL curve pattern and an increase in the levels of protein carbonyls and conjugated dienes. Among 125 sperm-containing semen samples, the TCL curve exhibited two patterns: a positive relative ratio curve (group A, 87 patients) and a negative relative ratio curve (group B, 38 patients). Sperm concentration was lower and total motile sperm and rapid motile sperm were fewer in group B. A significant correlation was found between TCL indices, conjugated dienes, and sperm quality in group B. CONCLUSION(S): Oxidation affects TCL curve pattern of proteins and lipids in a characteristic manner. Thermochemiluminescence indices in seminal plasma closely correlate with sperm characteristics among patients with sperm disturbances, and it might serve as a tool in the evaluation, treatment, and monitoring of subfertile men.


Assuntos
Estresse Oxidativo , Sêmen/metabolismo , Animais , Bovinos , Desenho de Equipamento , Equipamentos e Provisões , Humanos , Contagem de Leucócitos , Medições Luminescentes , Masculino , Oxirredução , Estudos Prospectivos , Sêmen/citologia , Soroalbumina Bovina/metabolismo , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Ácido alfa-Linolênico/metabolismo
19.
J Urol ; 170(1): 241-5, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12796697

RESUMO

PURPOSE: Prostate carcinomas show a low level of the cell cycle inhibitor p27, which correlates with tumor aggressiveness. In tumors p27 is of the WT species and its deregulation is due to aberrant ubiquitin mediated degradation. The p27 is degraded following phosphorylation and subsequent recognition by SCFSkp2 ubiquitin ligase. We examined the relationship between p27 and its specific ligase Skp2 in normal and malignant prostate tissues. A possible correlation among the levels of these proteins, tumor grading and clinical state was also investigated. MATERIALS AND METHODS: Using immunohistochemistry immunofluorescence microscopy and Western blot analysis 51 samples from needle biopsies, transurethral resection and radical prostatectomy were analyzed for p27 and Skp2 expression. Correlation with tumor grading (Gleason) was performed. In 22 proven metastatic or organ confined cases correlation was also done with the Ki67 proliferative marker. RESULTS: Skp2 expression demonstrated a significant and direct correlation with malignancy (p <0.0001). Furthermore, a significant correlation was found between Skp2 level and tumor aggressiveness graded by Gleason score (p <0.0002) and prostate specific antigen. Patients with metastases had significantly higher Skp2 and Ki67 expression than those with organ confined disease (p <0.0001). In addition, Skp2 levels significantly correlated with Ki67 (r = 0.73, p <0.0001). An inverse correlation was found between p27 and Skp2 ligase. CONCLUSIONS: Skp2 expression in prostate biopsies may be used as an additional marker for tumor aggressiveness. The results also suggest a role for Skp2 in the pathogenesis of prostate malignancy.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Quinases Ciclina-Dependentes/antagonistas & inibidores , Neoplasias da Próstata/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina/metabolismo , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Inibidor de Quinase Dependente de Ciclina p27 , Humanos , Immunoblotting , Imuno-Histoquímica , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Proteínas Quinases Associadas a Fase S
20.
Fertil Steril ; 79(3): 567-71, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12620441

RESUMO

OBJECTIVE: To compare activity of matrix metalloproteinases (MMP) and expression of their tissue-specific inhibitor (TIMP) in the follicular fluid of normally ovulating women and women with the polycystic ovary syndrome (PCOS). DESIGN: Prospective study. SETTING: IVF unit and endocrine research unit. PATIENT(S): Fourteen patients undergoing IVF treatment (seven with normal ovulation and seven with PCOS). MAIN OUTCOME MEASURE(S): Activity of MMP-2 and MMP-9 and expression of MMP-1, TIMP-1, and TIMP-2 was measured in follicular fluid of the leading follicles by using gel zymography and immunoblot analysis. RESULT(S): The activity of MMP-2 and MMP-9 and expression of MMP-1 was similar in follicular fluid of normally ovulating patients and patients with PCOS. Significantly lower expression of TIMP-1 was found in follicular fluid of patients with PCOS women compared with normally ovulating patients. CONCLUSION(S): Because MMPs and TIMPs play a role in the physical and chemical structure of the follicular compartment, the decreased expression of TIMP in patients with PCOS may be part of a compensatory process to overcome the physical properties of the thick ovarian capsule.


Assuntos
Fertilização in vitro , Líquido Folicular/química , Ovulação , Síndrome do Ovário Policístico/enzimologia , Inibidor Tecidual de Metaloproteinase-1/análise , Inibidor Tecidual de Metaloproteinase-2/análise , Adulto , Western Blotting , Eletroforese em Gel de Poliacrilamida , Feminino , Líquido Folicular/enzimologia , Humanos , Metaloproteinase 1 da Matriz/análise , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , Oócitos
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