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1.
Ultrasound Obstet Gynecol ; 55(3): 303-309, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31325336

RESUMO

OBJECTIVE: To compare the proportion of women achieving a desired ovarian response following ovarian stimulation when gonadotropin dosing was determined based on antral follicle count (AFC) vs serum anti-Müllerian hormone (AMH) level, in women undergoing in-vitro fertilization (IVF) using the gonadotropin-releasing hormone (GnRH) antagonist protocol. METHODS: This was a randomized double-blind trial carried out in a university-affiliated assisted reproduction unit. A total of 200 women undergoing their first IVF cycle using the GnRH-antagonist protocol between April 2016 and February 2018 were randomized to determination of gonadotropin dosing based on either AFC or serum AMH level measured in the pretreatment cycle 1 month before the IVF cycle. Patients underwent IVF as per our center's standard protocol. The proportion of subjects achieving a desired ovarian response, defined as retrieval of six to 14 oocytes, was compared between the two study arms. Subgroup analysis of patients with baseline AFC > 5 and those with baseline AFC ≤ 5 was performed. Concordance in AFC and AMH categorization between the pretreatment cycle and the ovarian-stimulation cycle was assessed using Cohen's kappa (κ). RESULTS: There was no significant difference in the proportion of patients achieving a desired ovarian response between the AFC (54%) and AMH (49%) groups (P = 0.479). The median number of oocytes retrieved was nine vs seven (P = 0.070), and the median follicular output rate was 0.54 vs 0.55 (P = 0.764) in the AFC and AMH groups, respectively. Similar findings were observed on subgroup analysis of subjects with AFC ≤ 5 and AFC > 5 at the start of ovarian stimulation (P > 0.05 for all comparisons). There was moderate concordance between AFC and AMH measured in the pretreatment cycle and the stimulation cycle (κ = 0.478 and 0.587, respectively). CONCLUSION: The proportion of women achieving a desired ovarian response following ovarian stimulation using the GnRH-antagonist protocol is similar when the gonadotropin-dosing algorithm used is based on AFC or serum AMH level. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Comparación del recuento de folículos sinusales y el nivel de la hormona antimulleriana en el suero para la determinación de la dosis de gonadotrofina en la fecundación in vitro: ensayo aleatorizado OBJETIVO: Comparar la proporción de mujeres que logran una respuesta ovárica deseada tras la estimulación del ovario cuando se determinó la dosis de gonadotrofina en función del recuento de folículos sinusales (AFC, por sus siglas en inglés) frente al nivel de la hormona antimulleriana (HAM) en el suero, en mujeres que se sometieron a una fecundación in vitro (FIV) mediante el protocolo de antagonistas de la hormona liberadora de gonadotropina (GnRH, por sus siglas en inglés). MÉTODOS: Se trata de un ensayo aleatorizado doble ciego realizado en una unidad de reproducción asistida afiliada a una universidad. Un total de 200 mujeres que se sometieron a su primer ciclo de FIV y utilizaron el protocolo de antagonistas de la GnRH entre abril de 2016 y febrero de 2018 fueron asignadas al azar a la determinación de la dosis de gonadotrofina basada en el nivel de AFC o de HAM en suero, medidos en el ciclo de pretratamiento un mes antes del ciclo de FIV. Las pacientes se sometieron a una FIV según el protocolo estándar de nuestro centro. La proporción de mujeres que lograron una respuesta ovárica deseada, definida como la recuperación de seis a 14 ovocitos, se comparó entre las dos ramas del estudio. Se realizó un análisis de subgrupos de las pacientes con AFC de base >5 y de aquellas con AFC de base ≤5. La concordancia en la categorización del AFC y la HAM entre el ciclo de pretratamiento y el ciclo de estimulación ovárica se evaluó utilizando la medida estadística kappa de Cohen (κ). RESULTADOS: No hubo diferencias significativas en la proporción de pacientes que lograron una respuesta ovárica deseada entre los grupos de AFC (54%) y HAM (49%) (P=0,479). La mediana del número de ovocitos recuperados fue de nueve frente a siete (P=0,070), y la mediana de la tasa de producción folicular fue de 0,54 frente a 0,55 (P=0,764) en los grupos AFC y HAM, respectivamente. Se observaron hallazgos similares en el análisis de subgrupos de pacientes con AFC ≤5 y AFC >5 al comienzo de la estimulación ovárica (P>0,05 para todas las comparaciones). Se observó una concordancia moderada entre el AFC y la HAM medidos en el ciclo de pretratamiento y el ciclo de estimulación (κ=0,478 y 0,587, respectivamente). CONCLUSIÓN: La proporción de mujeres que logran una respuesta ovárica deseada después de la estimulación ovárica utilizando el protocolo de antagonistas de la GnRH es similar cuando el algoritmo de dosificación de gonadotrofina utilizado se basa en el nivel del AFC o de la HAM en suero.


Assuntos
Hormônio Antimülleriano/sangue , Fertilização in vitro/métodos , Gonadotropinas/administração & dosagem , Antagonistas de Hormônios/administração & dosagem , Folículo Ovariano/crescimento & desenvolvimento , Adulto , Algoritmos , Método Duplo-Cego , Feminino , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Humanos , Indução da Ovulação/métodos , Gravidez , Resultado do Tratamento
2.
Hong Kong Med J ; 25(6): 468-472, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31796641

RESUMO

The popularity of in vitro fertilisation has continuously increased throughout the past 40 years owing to an increased incidence of infertility and delayed planning for pregnancy. The aim of this paper is to review the current situation of in vitro fertilisation in Hong Kong. In Hong Kong, in 2018, 7995 women underwent 5055 fresh and 5050 frozen-thawed embryo in vitro fertilisation cycles, resulting in an ongoing pregnancy rate of 33.7% per transfer. However, in vitro fertilisation is associated with several problems, including a high rate of multiple pregnancies and risks associated with cross-border reproductive care. Single embryo transfer is a simple strategy to reduce multiple pregnancies without compromising the cumulative live birth rate.


Assuntos
Fertilização in vitro/estatística & dados numéricos , Adulto , Feminino , Hong Kong , Humanos , Gravidez , Resultado da Gravidez
4.
Cell Tissue Res ; 368(3): 563-578, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28283910

RESUMO

Exposure to maternal diabetes during fetal growth is a risk factor for the development of type II diabetes (T2D) in later life. Discovery of the mechanisms involved in this association should provide valuable background for therapeutic treatments. Early embryogenesis involves epigenetic changes including histone modifications. The bivalent histone methylation marks H3K4me3 and H3K27me3 are important for regulating key developmental genes during early fetal pancreas specification. We hypothesized that maternal hyperglycemia disrupted early pancreas development through changes in histone bivalency. A human embryonic stem cell line (VAL3) was used as the cell model for studying the effects of hyperglycemia upon differentiation into definitive endoderm (DE), an early stage of the pancreatic lineage. Hyperglycemic conditions significantly down-regulated the expression levels of DE markers SOX17, FOXA2, CXCR4 and EOMES during differentiation. This was associated with retention of the repressive histone methylation mark H3K27me3 on their promoters under hyperglycemic conditions. The disruption of histone methylation patterns was observed as early as the mesendoderm stage, with Wnt/ß-catenin signaling being suppressed during hyperglycemia. Treatment with Wnt/ß-catenin signaling activator CHIR-99021 restored the expression levels and chromatin methylation status of DE markers, even in a hyperglycemic environment. The disruption of DE development was also found in mouse embryos at day 7.5 post coitum from diabetic mothers. Furthermore, disruption of DE differentiation in VAL3 cells led to subsequent impairment in pancreatic progenitor formation. Thus, early exposure to hyperglycemic conditions hinders DE development with a possible relationship to the later impairment of pancreas specification.


Assuntos
Diferenciação Celular , Endoderma/citologia , Histonas/metabolismo , Hiperglicemia/embriologia , Pâncreas/embriologia , Animais , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Azacitidina/farmacologia , Linhagem Celular , Linhagem da Célula , Metilases de Modificação do DNA/antagonistas & inibidores , Metilases de Modificação do DNA/metabolismo , Endoderma/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Inibidores Enzimáticos/farmacologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Glucose/farmacologia , Humanos , Hiperglicemia/metabolismo , Masculino , Mesoderma/metabolismo , Metilação , Camundongos , Camundongos Endogâmicos ICR , Pâncreas/citologia , Pâncreas/metabolismo , Regiões Promotoras Genéticas , Transdução de Sinais , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
5.
Andrologia ; 49(10)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28670753

RESUMO

Human varicella zoster virus (VZV) is a member of the herpes virus family and affects humans only. Information about the presence of the virus in the semen samples of men affected by chickenpox is rather limited in the literature. Here, we reported a husband was affected by VZV during in vitro fertilisation treatment of his wife treated in our centre. The semen sample was checked for the presence of VZV by the PCR technique. The PCR result found no detectable viral DNA in the semen sample. The semen sample was then used for conventional IVF insemination and subsequently a healthy baby boy was born. This single case report suggests that the semen sample of men affected by chickenpox may be safe to use for assisted reproduction methods during the VZV infective period.


Assuntos
Varicela/virologia , Herpesvirus Humano 3/isolamento & purificação , Sêmen/virologia , Adulto , Fertilização in vitro , Humanos , Masculino
6.
Hum Reprod ; 31(12): 2796-2802, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27702835

RESUMO

STUDY QUESTION: How do the three new anti-Müllerian hormone (AMH) assay methods, manufactured by Beckman Coulter, Roche and Ansh Labs compare with each other and with the Gen II assay? SUMMARY ANSWER: The three new AMH assays are well correlated among themselves and with the Gen II assay, although differences in calibration do exist. WHAT IS KNOWN ALREADY: The Gen II assay has been the mainstay method for AMH measurement in the past few years. Recently, a few new AMH measurement methods have come to the market. STUDY DESIGN, SIZE, DURATION: This was a prospective assay evaluation performed on 178 human serum samples. PARTICIPANTS/MATERIALS, SETTING, METHODS: AMH concentration was measured in residual serum samples donated by female patients in a reproductive medicine centre. The three new assay methods were tested in parallel and the numerical values obtained were compared among themselves and with those obtained by the Gen II assay. The assay stability upon different sample storage conditions, intra-assay and inter-assay precision, linearity and dilution recovery, and diagnostic performance for polycystic ovary syndrome (PCOS) of the three new AMH assay methods were also compared. MAIN RESULTS AND THE ROLE OF CHANCE: AMH values measured by the Gen II kit and the three new assay methods have good correlations (R > 0.9 for all pairwise correlations). Values measured by the Ansh Labs assay were significantly higher, whereas those by the Roche assay were significantly lower, than those from the Gen II and Beckman-Coulter automated assays (P < 0.05). AMH values were significantly different when measured on the fresh and frozen-thawed serum sample (at -20oC and -80oC) for all three new methods (P < 0.05), but the magnitude of difference was very small with the Beckman-Coulter automated assay and Roche assay. The intra-assay coefficients of variation (CVs) were 0.7-2.2%, 0.5-1.4%, and 1.4-5.4% for the Beckman-Counter automated, Roche and Ansh Labs assays, respectively. Their inter-assay CVs were 0.9-2.5%, 0.7-1.9%, and 6.2-13.5%, respectively. All three new assay methods showed acceptable linearity, and provided excellent discrimination of PCOS from controls. LIMITATIONS, REASONS FOR CAUTION: The precision and dilution linearity experiments involved a small sample size, although these were not the primary outcome measures and have been properly evaluated in previous publications. The study was not designed or powered for determining diagnostic cut-off values. WIDER IMPLICATIONS OF THE FINDINGS: The results demonstrate that the three new AMH assay methods are all valid methods to be adopted in the field of reproduction and are a basis for further work on their clinical application. STUDY FUNDING/COMPETING INTERESTS: The authors have no competing interest to declare. The execution of this study was funded by the Department of Obstetrics and Gynaecology, The University of Hong Kong.


Assuntos
Hormônio Antimülleriano/sangue , Imunoensaio/métodos , Feminino , Humanos , Estudos Prospectivos
7.
Hum Reprod ; 30(9): 2178-83, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26202923

RESUMO

STUDY QUESTION: Should fasting glucose (FG) or an oral glucose tolerance test (OGTT) be used to screen for dysglycaemia in women with polycystic ovary syndrome (PCOS)? SUMMARY ANSWER: A full OGTT should be recommended as the screening method for dysglycaemia in women with PCOS, regardless of BMI or family history of diabetes mellitus (DM). STUDY DESIGN, SIZE, DURATION: A cross-sectional study on 467 Chinese women diagnosed with PCOS by the Rotterdam criteria between January 2010 to December 2013. PARTICIPANTS, SETTING, METHODS: The study was done at a university hospital in Hong Kong. All subjects underwent a 75 g OGTT after overnight fasting. We evaluated the performance of FG alone, when compared with the full OGTT, in identifying subjects with dysglycaemia (prediabetes or DM, according to the 2010 diagnostic criteria of the American Diabetes Association). MAIN RESULTS AND THE ROLE OF CHANCE: Of the 467 subjects, 58 (12.4%) had dysglycaemia, among which 46 (9.8%) had prediabetes and 12 (2.6%) had DM, including 4 with known DM. Of the 46 subjects with prediabetes, 25 (54.3%) had normal FG and of the 8 subjects with screened DM in this study, 1 (12.5%) had normal FG. The sensitivity of FG alone in screening for prediabetes, DM and overall dysglycaemia were 45.7, 87.5 and 48.1%, respectively, i.e. missing 54.3% of prediabetes and 12.5% of DM cases as defined by the OGTT. Among the 54 subjects with screened dysglycaemia, 20 (37.0%) had BMI < 25 kg/m(2) and 35 (64.8%) had no family history of DM. LIMITATIONS, REASONS FOR CAUTION: We only reported on the biochemical diagnosis of DM based on a single time point. In clinical practice, confirmatory results at another time point is required for definitive diagnosis in asymptomatic subjects. WIDER IMPLICATIONS OF THE FINDINGS: There is an ongoing debate as to whether FG or an OGTT should be used as a screening method for dysglycaemia in women with PCOS. Some guidelines also recommend glucose screening only in those who are overweight and/or having family history of diabetes (DM). There have been scarce data on this issue in the Chinese population, which the current study aims at addressing. STUDY FUNDING/COMPETING INTERESTS: The study was supported by a research grant from the Hong Kong Obstetrical and Gynaecological Trust Fund, as well as internal research funding of the Department of Obstetrics and Gynaecology, The University of Hong Kong. All authors have no competing interests.


Assuntos
Glicemia/metabolismo , Transtornos do Metabolismo de Glucose/diagnóstico , Síndrome do Ovário Policístico/complicações , Adulto , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/etiologia , Feminino , Transtornos do Metabolismo de Glucose/etiologia , Teste de Tolerância a Glucose , Hong Kong , Humanos , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/etiologia
8.
Ultrasound Obstet Gynecol ; 40(4): 392-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22302719

RESUMO

OBJECTIVE: We previously demonstrated that a sequential regimen of letrozole and misoprostol resulted in a marked reduction in the serum estradiol concentration and in a higher efficacy of first-trimester termination of pregnancy than misoprostol alone. The aim of this study was to evaluate the effect of letrozole on uterine artery Doppler flow indices during early pregnancy. METHODS: This was a randomized controlled trial. Thirty women requesting termination of pregnancy up to 63 days' gestation were randomized into two groups: a letrozole group receiving 10 mg of letrozole, daily, for 3 days, and a control group receiving a placebo for 3 days. Serum estradiol, progesterone and human chorionic gonadotropin (hCG) concentrations were measured before drug administration and then daily for 6 days. Ultrasound scanning for fetal viability and measurement of the pulsatility (PI) and resistance (RI) indices of the uterine arteries was performed before drug administration, and then on day 3 and day 7 after starting letrozole or placebo. All pregnancies were terminated by surgical evacuation on day 7 or day 8. RESULTS: Uterine artery PI and RI decreased significantly in the letrozole group, but not in the control group. Serum estradiol concentrations were significantly lower in the letrozole group than in the control group from day 2 onwards. Serum progesterone and hCG concentrations were comparable for the two groups throughout the 7 days. There were significantly more women in the letrozole group with vaginal bleeding. CONCLUSION: We have demonstrated that the use of letrozole in the first trimester of pregnancy suppresses serum estradiol levels but results in an increase in blood flow to the uterus. Further studies should be carried out to elucidate the mechanism of letrozole pretreatment in medical abortion.


Assuntos
Abortivos não Esteroides/farmacologia , Aborto Induzido/métodos , Nitrilas/farmacologia , Fluxo Pulsátil/efeitos dos fármacos , Triazóis/farmacologia , Artéria Uterina/efeitos dos fármacos , Artéria Uterina/diagnóstico por imagem , Hemorragia Uterina/induzido quimicamente , Abortivos não Esteroides/administração & dosagem , Abortivos não Esteroides/efeitos adversos , Adulto , Gonadotropina Coriônica/sangue , Estradiol/sangue , Feminino , Hong Kong/epidemiologia , Humanos , Letrozol , Pessoa de Meia-Idade , Nitrilas/administração & dosagem , Gravidez , Primeiro Trimestre da Gravidez , Cuidados Pré-Operatórios , Progesterona/sangue , Resultado do Tratamento , Triazóis/administração & dosagem , Ultrassonografia Doppler , Artéria Uterina/fisiopatologia
9.
Biol Reprod ; 84(5): 1016-23, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21209418

RESUMO

Perfluorooctanesulfonate (PFOS) was produced and used by various industries and in consumer products. Because of its persistence, it is ubiquitous in air, water, soil, wildlife, and humans. Although the adverse effects of PFOS on male fertility have been reported, the underlying mechanisms have not yet been elucidated. Here, for the first time, the effects of PFOS on testicular signaling, such as gonadotropin, growth hormone, insulin-like growth factor, and inhibins/activins were shown to be directly related to male subfertility. Sexually mature 8-wk-old CD1 male mice were administered by gavages in corn oil daily with 0, 1, 5, or 10 mg/kg PFOS for 7, 14, or 21 days. Serum concentrations of testosterone and epididymal sperm counts were significantly lower in the mice after 21 days of the exposure to the highest dose compared with the controls. The expression levels of testicular receptors for gonadotropin, growth hormone, and insulin-like growth factor 1 were considerably reduced on Day 21 in mice exposed daily to 10 or 5 mg/kg PFOS. The transcript levels of the subunits of the testicular factors (i.e., inhibins and activins), Inha, Inhba, and Inhbb, were significantly lower on Day 21 of daily exposure to 10, 5, or 1 mg/kg PFOS. The mRNA expression levels of steroidogenic enzymes (i.e., StAR, CYP11A1, CYP17A1, 3beta-HSD, and 17beta-HSD) were notably reduced. Therefore, PFOS-elicited subfertility in male mice is manifested as progressive deterioration of testicular signaling.


Assuntos
Ácidos Alcanossulfônicos/toxicidade , Poluentes Ambientais/toxicidade , Fluorocarbonos/toxicidade , Sistema Hipotálamo-Hipofisário/fisiologia , Infertilidade Masculina/induzido quimicamente , Transdução de Sinais/efeitos dos fármacos , Testículo/fisiologia , Ativinas/genética , Ativinas/metabolismo , Ácidos Alcanossulfônicos/administração & dosagem , Animais , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Poluentes Ambientais/administração & dosagem , Epididimo/citologia , Epididimo/efeitos dos fármacos , Fluorocarbonos/administração & dosagem , Infertilidade Masculina/metabolismo , Inibinas/genética , Inibinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos , Oligospermia/induzido quimicamente , RNA Mensageiro/metabolismo , Distribuição Aleatória , Receptor IGF Tipo 1/metabolismo , Receptores da Gonadotropina/metabolismo , Receptores da Somatotropina/metabolismo , Testosterona/sangue
10.
Sci Adv ; 6(37)2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32917695

RESUMO

Embryonic diapause is a maternally controlled phenomenon. The molecule controlling the onset of the phenomenon is unknown. We demonstrated that overexpression of microRNA let-7a or incubation with let-7g-enriched extracellular vesicles from endometrial epithelial cells prolonged the in vitro survival of mouse blastocysts, which developed into live pups after having been transferred to foster mothers. Similar to in vivo dormant blastocysts, let-7-induced dormant blastocysts exhibited low level of proliferation, apoptosis, and nutrient metabolism. Let-7 suppressed c-myc/mTORC1 and mTORC2 signaling to induce embryonic diapause. It also inhibited ODC1 expression reducing biosynthesis of polyamines, which are known to reactivate dormant embryos. Furthermore, the overexpression of let-7 blocked trophoblast differentiation and implantation potential of human embryo surrogates, and prolonged survival of human blastocysts in vitro, supporting the idea that embryonic diapause was an evolutionary conserved phenomenon. In conclusion, let-7 is the main factor inducing embryonic diapause.


Assuntos
Diapausa , Vesículas Extracelulares , MicroRNAs , Animais , Blastocisto/fisiologia , Implantação do Embrião/genética , Desenvolvimento Embrionário/genética , Endométrio/metabolismo , Vesículas Extracelulares/metabolismo , Feminino , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo
11.
Int J Androl ; 32(6): 687-94, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19076257

RESUMO

Leptin is a polypeptide hormone with important roles in reproduction. It has been detected in human seminal plasma as well as on human ejaculated spermatozoa. This study aimed at studying the possible role of leptin in regulating human sperm functions. Immunofluorescent staining was used to study the expression of leptin and its receptor. The correlation between the concentration of leptin and soluble leptin receptor (ObRs) in seminal plasma as measured by enzyme-linked immunosorbant assay and sperm motility parameters measured by computer-assisted sperm analysis (CASA) was determined. The effects of recombinant leptin on human sperm motility, capacitation and acrosome reaction as measured by chlortetracycline staining were also studied. Leptin immunoreactivity was demonstrated at the equatorial and neck regions of human spermatozoa, whereas that of ObRs was shown up on the tail. After Percoll separation, spermatozoa with high density had more intense leptin immunoreactivity compared with those with low density. No significant correlation was found between seminal plasma concentration of leptin/ObRs and sperm motility parameters. After incubation with recombinant human leptin for either 3 h or overnight, there was no change in all the CASA motility parameters determined and percentages of capacitated and acrosome-reacted spermatozoa. We concluded that leptin does not have a significant effect on motility and capacitation/acrosome reaction in human ejaculated mature spermatozoa. Its role in male reproduction is yet to be determined.


Assuntos
Reação Acrossômica/efeitos dos fármacos , Leptina/metabolismo , Leptina/farmacologia , Capacitação Espermática/efeitos dos fármacos , Motilidade dos Espermatozoides/efeitos dos fármacos , Reação Acrossômica/fisiologia , Contagem de Células , Clortetraciclina/metabolismo , Clortetraciclina/farmacologia , Humanos , Masculino , Sêmen/metabolismo , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Espermatozoides/fisiologia
12.
J Chromatogr B Analyt Technol Biomed Life Sci ; 797(1-2): 217-28, 2003 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-14630151

RESUMO

Capillary electrophoresis-based immunoassay (CEIA) is a developing analytical technique with a number of advantages over conventional immunoassay, such as reduced sample consumption, simpler procedure, easy simultaneous determination of multiple analytes, and short analysis time. However, there are still a number of technical issues that researchers on CEIA have to solve before the assay can be more widely used. These issues include method to improve the concentration sensitivity of the assay, requirement for robust separation strategy for different analytes, and method to increase the throughput of the assay. The approaches to solve these issues are reviewed. Several studies have been devoted to develop general separation strategies for CEIA, and to enhance the sensitivity of detection. The recent development of microchip-based CEIA is encouraging and is likely to address more drawbacks of CEIA, particularly on the throughput issue.


Assuntos
Eletroforese Capilar/métodos , Imunoensaio/métodos , Reações Antígeno-Anticorpo , Semicondutores , Sensibilidade e Especificidade
13.
Int J Gynecol Cancer ; 5(1): 15-19, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11578447

RESUMO

Urinary human chorionic gonadotrophin beta-core (hCG-betaC) was detected in 55-77% of gynecologic malignancies. The use of spot and early morning urine hCG-betaC as a tumor marker was explored with regard to the stability of the hCG-betaC level in serial spot urine samples collected within 24 hours and in early morning urine collected over 3 days. Thirteen patients with gynecologic malignancies were asked, before treatment, to collect serial urine samples voided within 24 hours. Nine of these 13 patients were also asked to save early morning urine for 2-3 consecutive days. Their urine was assayed for creatinine and hCG-betaC using an immunoradiometric assay. Variation of urine concentration was corrected by using the hCG-betaC/creatinine (betaC/Cr) ratio expressed in pmolg-1. Wide fluctuations of betaC/Cr ratios were found both in the serial spot urine within 24 hours and in early morning urine within 3 days. Eight per cent of the patients had one or more spot hCG-betaC level double or half the median of their own serial urine samples. Neither spot urine nor early morning urine hCG-betaC were suitable for use as a tumor marker for continuous monitoring because of the large fluctuation in hCG-betaC levels. The reason for such a wide fluctuation is not clear.

14.
Hong Kong Med J ; 9(5): 341-5, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14530528

RESUMO

OBJECTIVE: To determine the prognostic factors associated with successful outcome following controlled ovarian stimulation and intrauterine insemination. DESIGN: Retrospective analysis. SETTING: University-based assisted reproductive technology centre, Hong Kong. PATIENTS AND METHODS: Patients included 292 couples undergoing 600 treatment cycles, following a standard protocol of human menopausal gonadotrophin injections. Multiple logistic regression analysis was performed to determine which demographic and sperm parameters gave the maximum discrimination to predict pregnancy. RESULTS: One hundred and eleven pregnancies resulted from treatment. The pregnancy rates were 18.5% per cycle and 37.9% per couple. The age of the women was significantly lower for pregnant cycles, and the serum oestradiol levels and number of follicles greater than 16 mm in diameter were significantly higher, compared with non-pregnant cycles. The sperm concentration and number of motile spermatozoa were also significantly increased in pregnant cycles. Pregnancy rate was significantly increased when the raw semen sample contained 20 million/mL or more spermatozoa, normal forms comprised 7% or more, and when the number of motile spermatozoa in inseminated samples was 1 million or greater. CONCLUSION: Using multiple logistic regression analysis, age of the women and serum oestradiol level had the maximum power to predict pregnancy following ovarian stimulation and intrauterine insemination.


Assuntos
Inseminação Artificial Homóloga , Indução da Ovulação , Adulto , Estradiol/sangue , Feminino , Humanos , Modelos Logísticos , Masculino , Idade Materna , Avaliação de Resultados em Cuidados de Saúde , Folículo Ovariano , Gravidez , Taxa de Gravidez , Prognóstico , Estudos Retrospectivos , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides
15.
Hong Kong Med J ; 9(1): 43-7, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12547956

RESUMO

This paper presents the first two successful cases of pre-implantation genetic diagnosis in Hong Kong and discusses the indications and the advantages over prenatal diagnosis. Patients should be informed about the procedure and extensively counselled about the possibility of misdiagnosis and the need for conventional prenatal diagnosis during pregnancy.


Assuntos
Diagnóstico Pré-Implantação , Adulto , Aconselhamento , Transferência Embrionária , Feminino , Hong Kong , Humanos , Masculino , Diagnóstico Pré-Natal
16.
Andrology ; 2(6): 868-74, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25168311

RESUMO

Ulipristal acetate (UPA) and mifepristone are currently well-established agents for emergency contraception. Both drugs are selective progestogen receptor modulators which have been shown to have better efficacy than the widely used levonorgestrel in prevention of pregnancy. However, there is only limited information on the action of UPA on sperm function. The present study compared the in vitro biological effects of mifepristone and UPA on human sperm functions. Spermatozoa from semen samples with normal semen parameters were isolated. Capacitated spermatozoa were pre-incubated with 0.04, 0.4, 4 and 40 µM mifepristone or UPA for 1 h. Sperm motility, viability, DNA integrity, capacitation, spontaneous acrosome reaction, spontaneous hyperactivation, zona pellucida (ZP) binding capability and intracellular calcium concentration ([Ca(2+)]i) were determined. The effects of mifepristone and UPA on progesterone-induced acrosome reaction, hyperactivation and [Ca(2+)]i were also studied. Our results showed that mifepristone and UPA dose-dependently suppressed progesterone-induced acrosome reaction, hyperactivation and [Ca(2+)]i at concentrations ≥0.4 µM in human spermatozoa. Both compounds did not affect sperm motility, viability, DNA integrity, capacitation, spontaneous acrosome reaction, spontaneous hyperactivation, ZP binding capability and [Ca(2+)]i. This study demonstrated that UPA and mifepristone modulate human sperm functions by acting as progesterone antagonists. The results enable us to gain a better understanding of the mechanisms by which mifepristone and UPA work for emergency contraception, and provide a scientific basis for their clinical application.


Assuntos
Mifepristona/farmacologia , Norpregnadienos/farmacologia , Espermatozoides/efeitos dos fármacos , Reação Acrossômica , Cálcio/metabolismo , Humanos , Técnicas In Vitro , Masculino , Capacitação Espermática , Motilidade dos Espermatozoides
17.
Placenta ; 33(9): 750-2, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22748851

RESUMO

Cytotrophoblasts are the key trophoblast cells which differentiate into different trophoblast lineages. In this report, glycodelin-A action on fusion of a cytotrophoblast-like cell line (BeWo) was investigated. It significantly reduced the spontaneous fusion of BeWo cells. The treatment enhanced the invasion and extracellular-signal regulated kinases activation of BeWo cells. The mRNA expression of syncytialization markers, human chorionic gonadotrophin and glial cells missing homolog 1 were suppressed upon glycodelin-A treatment. The data suggest a possible function of glycodelin-A in mediating cytotrophoblast differentiation.


Assuntos
Glicoproteínas/farmacologia , Proteínas da Gravidez/farmacologia , Trofoblastos/fisiologia , Antígeno Carcinoembrionário/genética , Diferenciação Celular/fisiologia , Fusão Celular , Linhagem Celular Tumoral , Coriocarcinoma , Gonadotropina Coriônica Humana Subunidade beta/genética , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/análise , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Expressão Gênica/efeitos dos fármacos , Glicodelina , Glicoproteínas/fisiologia , Humanos , Proteínas da Gravidez/fisiologia , Trofoblastos/efeitos dos fármacos
18.
J Clin Endocrinol Metab ; 97(6): 2105-12, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22456622

RESUMO

CONTEXT: Tubal ectopic pregnancy (tEP) is currently the leading cause of pregnancy-related deaths during the first trimester. Our current knowledge on the molecular pathogenesis is limited. OBJECTIVE: The objective of the study was to find out the possible role of adrenomedullin (ADM) in the pathogenesis of tEP. DESIGN: This was an experimental in vitro study on oviductal tissue. SETTING: The study was conducted at a university teaching hospital. PATIENTS AND INTERVENTIONS: Patients included those having oviducts removed surgically during salpingectomy for tEP or hysterectomy for benign gynecological conditions. Oviductal tissues were incubated in hormonal condition mimicking early pregnancy before used for in vitro experiments. MAIN OUTCOME MEASURES: Plasma ADM concentration, oviductal expression of ADM and its receptors, ciliary beat frequency, smooth muscle contraction were measured. RESULTS: The ciliary beat frequency and frequency of muscle contraction were lower in the oviducts from patients with tEP than those from simulated normal pregnancy. The plasma and oviductal tissue ADM levels were also lower. The decreases in ciliary beat and frequency of contraction were restored to normal after ADM treatment. CONCLUSIONS: The results suggest that the lower ADM level in the oviducts of tEP may lead to the decrease in ciliary beating and muscle contraction, with the result that the embryo is retained and implanted in the oviduct. Our findings explain for the first time the etiology of tubal pregnancy on the basis of an impairment of the transport of the fertilized ovum resulting from an ADM deficiency and raise the possibility of using the plasma ADM level as a predictor for tubal ectopic pregnancy.


Assuntos
Adrenomedulina/fisiologia , Tubas Uterinas/fisiologia , Gravidez Tubária/etiologia , Gravidez Tubária/fisiopatologia , Adrenomedulina/sangue , Adrenomedulina/genética , Adulto , Biomarcadores/sangue , Cílios/fisiologia , Implantação do Embrião/fisiologia , Feminino , Expressão Gênica/fisiologia , Humanos , Pessoa de Meia-Idade , Músculo Liso/fisiologia , Valor Preditivo dos Testes , Gravidez , Gravidez Tubária/sangue , Receptores de Adrenomedulina/genética , Receptores de Adrenomedulina/fisiologia
19.
Reprod Toxicol ; 31(4): 409-17, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21182934

RESUMO

Bisphenol A (BPA) is used in the manufacture of many products and is ubiquitous in the environment. Adverse effects of BPA on animal reproductive health have been reported, however most of the studies relied on the approaches in the assessment of conventional histology and anatomical features. The mechanistic actions of BPA are not clear. In the present study, a murine model was used to study potential effects of BPA exposure during perinatal and postnatal periods on endocrine functions of hypothalamic-pituitary-gonadal (HPG)-axis. At the hypothalamic-pituitary level, BPA exposure resulted in the up-regulation of the expression levels of KiSS-1, GnRH and FSH mRNA in both male and female pups. At the gonadal levels, BPA caused inhibition in the expressions of testicular steroidogenic enzymes and the synthesis of testosterone in the male pups. Conversely exposure to BPA resulted in a greater aromatase expression level and the synthesis of estrogen in the female pups. BPA is a weak estrogen agonist and its effects reported on animal studies are difficult to reconcile with mechanistic action of estrogen. In this study we hypothesized that the effects of BPA on reproductive dysfunction may be due to its actions on gonadal steroidogenesis and so the anomalous releases of endogenous steroid hormones. This non-ER-mediated effect is more potent in affecting the feedback regulatory circuits in the HPG-axis.


Assuntos
Disruptores Endócrinos/toxicidade , Poluentes Ambientais/toxicidade , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Ovário/efeitos dos fármacos , Fenóis/toxicidade , Reprodução/efeitos dos fármacos , Testículo/efeitos dos fármacos , Fatores Etários , Envelhecimento , Análise de Variância , Animais , Compostos Benzidrílicos , Relação Dose-Resposta a Droga , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Idade Gestacional , Hormônios Esteroides Gonadais/biossíntese , Gonadotropinas Hipofisárias/metabolismo , Sistema Hipotálamo-Hipofisário/crescimento & desenvolvimento , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Camundongos , Nível de Efeito Adverso não Observado , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal , RNA Mensageiro/metabolismo , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Receptores Acoplados a Proteínas G/genética , Receptores de Peptídeos/efeitos dos fármacos , Receptores de Peptídeos/genética , Receptores de Esteroides/efeitos dos fármacos , Receptores de Esteroides/genética , Testículo/crescimento & desenvolvimento , Testículo/metabolismo
20.
Hum Reprod Update ; 13(3): 275-87, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17329396

RESUMO

Glycodelin is an example of a glycoprotein whose complex-type glycans mediate biological actions in human reproduction and immune reactions. Being attached to an identical protein backbone, glycodelin oligosaccharides vary significantly from one reproductive tissue to another and have an effect on its own secretion and role in cell communication. For instance, uterine glycodelin-A inhibits sperm-oocyte interaction by binding on the sperm head. This is a glycosylation-dependent phenomenon, in which fucosyltransferase-5 plays a key role. Glycodelin-S from seminal plasma binds evenly around the sperm head and maintains an uncapacitated state in the spermatozoa, until the isoform is detached during sperm passage through the cervix. Glycodelin-F from follicular fluid and Fallopian tube binds to the acrosomal region of the sperm head, thereby inhibiting both the sperm-oocyte binding and premature progesterone-induced acrosome reaction. The cumulus cells surrounding the oocyte can capture glycodelin-A and -F from the surrounding environment and convert these isoforms to a cumulus cell isoform, glycodelin-C. It differs by glycosylation from the other isoforms, and it too attaches on the sperm head, with the highest density in the equatorial region. Glycodelin-C is capable of detaching the sperm-bound inhibitory isoforms so that the sperm-oocyte binding is enhanced. Glycodelin-A also has immunosuppressive actions directed to cellular, humoral and innate immunity. Although these actions depend mainly on the protein backbone, glycosylation also plays a part. Glycosylated glycodelin may be involved in the protection of spermatozoa against maternal immune reactions, and glycodelin also has apoptogenic activity. Some glycosylation patterns of glycodelin may mask its apoptogenic domain. This review updates the recent research and clinical associations of glycodelin, highlighting the role of glycosylation.


Assuntos
Células Germinativas/imunologia , Células Germinativas/metabolismo , Glicoproteínas/metabolismo , Linfócitos/metabolismo , Proteínas da Gravidez/metabolismo , Interações Espermatozoide-Óvulo/imunologia , Feminino , Glicodelina , Glicosilação , Humanos , Linfócitos/imunologia , Masculino , Oócitos/citologia , Oócitos/metabolismo , Espermatozoides/citologia , Espermatozoides/metabolismo
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