RESUMO
Somatic cell nuclear transfer (SCNT) has been an area of interest in the field of stem cell research and regenerative medicine for the past 20 years. The main biological goal of SCNT is to reverse the differentiated state of a somatic cell, for the purpose of creating blastocysts from which embryonic stem cells (ESCs) can be derived for therapeutic cloning, or for the purpose of reproductive cloning. However, the consensus is that the low efficiency in creating normal viable offspring in animals by SCNT (1-5%) and the high number of abnormalities seen in these cloned animals is due to epigenetic reprogramming failure. In this review we provide an overview of the current literature on SCNT, focusing on protocol development, which includes early SCNT protocol deficiencies and optimizations along with donor cell type and cell cycle synchrony; epigenetic reprogramming in SCNT; current protocol optimizations such as nuclear reprogramming strategies that can be applied to improve epigenetic reprogramming by SCNT; applications of SCNT; the ethical and legal implications of SCNT in humans; and specific lessons learned for establishing an optimized SCNT protocol using a mouse model.
Assuntos
Blastocisto/citologia , Células-Tronco Embrionárias/citologia , Técnicas de Transferência Nuclear , Animais , Diferenciação Celular , Reprogramação Celular , Clonagem de Organismos/métodos , Embrião de Mamíferos/citologia , Desenvolvimento Embrionário , Epigenômica , Enucleação Ocular , Humanos , Oócitos/citologiaRESUMO
A survey among gynaecologists practising in Libreville was conducted to ascertain the level of infertility assistance available, and the feasibility of establishing an intrauterine insemination programme in Gabon. This descriptive study invited gynaecologists (n=20) in both private and public hospitals, who are members at the Gabonese Society of Obstetricians Gynaecologists and Reproduction, to participate in the survey. Seventeen (85%) surveys were completed. The information obtained indicated that each gynaecologist consulted with more than fifty patients monthly, and nearly half (45%) of these consultations were infertility related. Male patients were referred to four different pathology laboratories in Libreville for basic semen analyses (without microbiology testing). Nearly 65% of the respondents referred female patients for further infertility treatments elsewhere. Approximately one-third of all couples were unable to access additional medical assistance. This survey can be viewed as motivation for health policymakers to initiate discussions to improve medical diagnostics and implement accessible fertility services in Gabon. Gynaecological expertise, together with a developed infrastructure in Libreville, could serve as an appropriate base for the advancement of reproductive treatment facilities.
Assuntos
Ginecologia , Infertilidade/terapia , Médicos , Técnicas de Reprodução Assistida , Adulto , Feminino , Gabão , Humanos , Masculino , Inquéritos e QuestionáriosRESUMO
The risk of human immunodeficiency virus (HIV) transmission to the female partner, or potential offspring of an HIV-1 infected man can be reduced using semen decontamination procedures before assisted reproductive treatment (ART). The objective of this study was to determine the efficiency of decontaminating semen samples (n = 186) from 95 HIV-1 sero-positive patients. Aliquots of neat semen were submitted for viral validation by qualitative and quantitative polymerase chain reaction. Semen samples were processed by density gradient centrifugation in combination with a ProInsert™ tube after which aliquots of the processed sperm samples were analysed for the presence of HIV-1. Fifty-four percent of all tested neat semen samples tested positive for HIV-1 DNA, RNA or both (13.4%, 11.3% and 29.0%, respectively). From a total of 103 processed sperm samples that were submitted for viral validation, two samples tested positive for HIV-1 DNA and none for RNA. In conclusion, semen processing with the ProInsert™ followed by viral validation of processed sperm samples should be carried out when providing ART to couples where the male partner is HIV-1 sero-positive.
Assuntos
Descontaminação/métodos , Infecções por HIV/prevenção & controle , Soropositividade para HIV/transmissão , HIV-1/isolamento & purificação , Preservação do Sêmen/métodos , Sêmen/virologia , Adulto , Centrifugação com Gradiente de Concentração/instrumentação , Criopreservação , DNA Viral/isolamento & purificação , DNA Viral/metabolismo , Descontaminação/instrumentação , Infecções por HIV/metabolismo , Infecções por HIV/transmissão , Infecções por HIV/virologia , Soropositividade para HIV/metabolismo , Soropositividade para HIV/virologia , HIV-1/metabolismo , Humanos , Limite de Detecção , Masculino , Reação em Cadeia da Polimerase , RNA Viral/isolamento & purificação , RNA Viral/metabolismo , Reprodutibilidade dos Testes , Técnicas de Reprodução Assistida/efeitos adversos , Sêmen/metabolismo , Preservação do Sêmen/instrumentação , Carga ViralRESUMO
This study investigated the effects of long-term (24h) in-vitro sperm incubation at room temperature (RT; 23°C) versus testis temperature (35°C) on various sperm-quality parameters. Semen samples (n=41) were prepared both by density-gradient centrifugation (DGC) and the swim-up technique in order to compare the influence of sperm preparation on sperm quality after incubation. Progressive motility and morphology were significantly higher after incubation at RT compared with 35°C (P<0.001 and P<0.01, respectively). The proportions of acrosome-reacted, apoptotic and dead spermatozoa were significantly lower in samples incubated for 24h at RT compared with 35°C (P<0.001, P=0.01 and P<0.001, respectively). The number of motile, morphologically normal, non-acrosome-reacted and nonapoptotic spermatozoa recovered after sperm preparation was significantly higher in DGC compared with swim-up samples (P<0.001). However, spermatozoa prepared by swim-up showed better survival after incubation compared with DGC-prepared spermatozoa, especially when incubated at 35°C. In conclusion, this study indicates a significantly better and longer preservation of sperm quality when incubation is performed at RT. These findings may convince laboratories to change the routinely used sperm storage conditions in order to maximize the quality of the prepared sperm sample.
Assuntos
Separação Celular/métodos , Preservação do Sêmen/métodos , Centrifugação com Gradiente de Concentração , Humanos , Masculino , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides , TemperaturaRESUMO
STUDY QUESTION: We aim to develop, disseminate and implement a minimum data set, known as a core outcome set, for future male infertility research. WHAT IS KNOWN ALREADY: Research into male infertility can be challenging to design, conduct and report. Evidence from randomized trials can be difficult to interpret and of limited ability to inform clinical practice for numerous reasons. These may include complex issues, such as variation in outcome measures and outcome reporting bias, as well as failure to consider the perspectives of men and their partners with lived experience of fertility problems. Previously, the Core Outcome Measure for Infertility Trials (COMMIT) initiative, an international consortium of researchers, healthcare professionals and people with fertility problems, has developed a core outcome set for general infertility research. Now, a bespoke core outcome set for male infertility is required to address the unique challenges pertinent to male infertility research. STUDY DESIGN SIZE DURATION: Stakeholders, including healthcare professionals, allied healthcare professionals, scientists, researchers and people with fertility problems, will be invited to participate. Formal consensus science methods will be used, including the modified Delphi method, modified Nominal Group Technique and the National Institutes of Health's consensus development conference. PARTICIPANTS/MATERIALS SETTING METHODS: An international steering group, including the relevant stakeholders outlined above, has been established to guide the development of this core outcome set. Possible core outcomes will be identified by undertaking a systematic review of randomized controlled trials evaluating potential treatments for male factor infertility. These outcomes will be entered into a modified Delphi method. Repeated reflection and re-scoring should promote convergence towards consensus outcomes, which will be prioritized during a consensus development meeting to identify a final core outcome set. We will establish standardized definitions and recommend high-quality measurement instruments for individual core outcomes. STUDY FUNDING/COMPETING INTERESTS: This work has been supported by the Urology Foundation small project award, 2021. C.L.R.B. is the recipient of a BMGF grant and received consultancy fees from Exscentia and Exceed sperm testing, paid to the University of Dundee and speaking fees or honoraria paid personally by Ferring, Copper Surgical and RBMO. S.B. received royalties from Cambridge University Press, Speaker honoraria for Obstetrical and Gynaecological Society of Singapore, Merk SMART Masterclass and Merk FERRING Forum, paid to the University of Aberdeen. Payment for leadership roles within NHS Grampian, previously paid to self, now paid to University of Aberdeen. An Honorarium is received as Editor in Chief of Human Reproduction Open. M.L.E. is an advisor to the companies Hannah and Ro. B.W.M. received an investigator grant from the NHMRC, No: GNT1176437 is a paid consultant for ObsEva and has received research funding from Ferring and Merck. R.R.H. received royalties from Elsevier for a book, consultancy fees from Glyciome, and presentation fees from GryNumber Health and Aytu Bioscience. Aytu Bioscience also funded MiOXYS systems and sensors. Attendance at Fertility 2020 and Roadshow South Africa by Ralf Henkel was funded by LogixX Pharma Ltd. R.R.H. is also Editor in Chief of Andrologia and has been an employee of LogixX Pharma Ltd. since 2020. M.S.K. is an associate editor with Human Reproduction Open. K.Mc.E. received an honoraria for lectures from Bayer and Pharmasure in 2019 and payment for an ESHRE grant review in 2019. His attendance at ESHRE 2019 and AUA 2019 was sponsored by Pharmasure and Bayer, respectively. The remaining authors declare no competing interests. TRIAL REGISTRATION NUMBER: Core Outcome Measures in Effectiveness Trials (COMET) initiative registration No: 1586. Available at www.comet-initiative.org/Studies/Details/1586. TRIAL REGISTRATION DATE: N/A. DATE OF FIRST PATIENT'S ENROLMENT: N/A.
RESUMO
Ejaculated, density purified, human spermatozoa were exposed to pulsed 900 MHz GSM mobile phone radiation at two specific absorption rate levels (SAR 2.0 and 5.7 W/kg) and compared with controls over time. Change in sperm mitochondrial membrane potential was analysed using flow cytometry. Sperm motility was determined by computer assisted sperm analysis (CASA). There was no effect of pulsed 900 MHz GSM radiation on mitochondrial membrane potential. This was also the case for all kinematic parameters assessed at a SAR of 2.0 W/kg. However, over time, the two kinematic parameters straight line velocity (VSL) and beat-cross frequency (BCF) were significantly impaired (P < 0.05) after the exposure at SAR 5.7 W/kg and no exposure by time interaction was present. This result should not be ascribed to thermal effects, due to the cooling methods employed in the RF chamber and temperature control within the incubator.
Assuntos
Telefone Celular , Potencial da Membrana Mitocondrial/fisiologia , Potencial da Membrana Mitocondrial/efeitos da radiação , Micro-Ondas , Motilidade dos Espermatozoides/fisiologia , Motilidade dos Espermatozoides/efeitos da radiação , Células Cultivadas , Relação Dose-Resposta à Radiação , Humanos , Doses de RadiaçãoRESUMO
Abstract Recent reports suggest that mobile phone radiation may diminish male fertility. However, the effects of this radiation on human spermatozoa are largely unknown. The present study examined effects of the radiation on induction of apoptosis-related properties in human spermatozoa. Ejaculated, density-purified, highly motile human spermatozoa were exposed to mobile phone radiation at specific absorption rates (SARs) of 2.0 and 5.7 W/kg. At various times after exposure, flow cytometry was used to examine caspase 3 activity, externalization of phosphatidylserine (PS), induction of DNA strand breaks, and generation of reactive oxygen species. Mobile phone radiation had no statistically significant effect on any of the parameters studied. This suggests that the impairment of fertility reported in some studies was not caused by the induction of apoptosis in spermatozoa.
Assuntos
Telefone Celular/estatística & dados numéricos , Apoptose/efeitos da radiação , Caspase 3/metabolismo , Caspase 3/efeitos da radiação , Caspases/metabolismo , Caspases/efeitos da radiação , Fertilidade , Humanos , Infertilidade Masculina/diagnóstico por imagem , Masculino , Estresse Oxidativo , Exposição Paterna , Cintilografia , Espermatozoides/enzimologia , Espermatozoides/fisiologia , Espermatozoides/efeitos da radiaçãoRESUMO
OBJECTIVE: To determine the effectiveness of a novel treatment designed to remove human immunodeficiency virus (HIV) -1 and hepatitis C virus (HCV) from spiked semen and to evaluate sperm motility and viability after treatment. DESIGN: A prospective clinical laboratory-based study. SETTING: The human studies were conducted in academic and national research environments. The bovine study was conducted in an accredited research facility. PATIENT(S): Healthy volunteers provided the semen samples used in the human studies; abattoir-derived material was used for the bovine embryo production study. INTERVENTIONS(S): None. MAIN OUTCOME MEASURE(S): Cytopathic, reverse transcriptase-polymerase chain reaction, and branched DNA assays were used to test the efficacy of the procedure for inactivating or removing viruses from spiked semen; standard semen evaluation criteria were used to assess the effects of the procedures on sperm motility and viability. RESULT(S): Trypsin exposure significantly reduced the infectivity of HIV-1. The triple density gradient treatment, with or without trypsin, had no detrimental affect on fresh or cryopreserved/thawed sperm 2-48 hours after treatment. The treatment of semen spiked with HIV-1 or HCV indicated that the procedure was effective for reducing viral copies to undetectable levels or below levels of clinical relevance. CONCLUSION(S): The procedure was effective for significantly inactivating or reducing HIV-1 and HCV in spiked semen without adversely affecting sperm quality.