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1.
Zygote ; : 1-7, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953841

RESUMO

In vitro maturation of oocytes (IVM) represents an assisted reproductive technique that involves the minimal or absence of ovarian stimulation and is beneficial to specific groups of patients. These may include women with polycystic ovarian syndrome and/or patients who need a fertility preservation option before undergoing gonadotoxic treatment. However, when IVM is applied in cases where it is not recommended, it can be considered as an add-on technique, as described by the ESHRE Guideline Group on Female Fertility Preservation. Interestingly, IVM has not been proven yet to be as effective as conventional IVF in the laboratory, in terms of clinical pregnancy and live birth rates, while concerns have been raised for its long-term safety. As a result, both safety and efficacy of IVM remain still questionable and additional data are needed to draw conclusions.

2.
Reprod Biomed Online ; 46(2): 363-370, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36604213

RESUMO

RESEARCH QUESTION: Are oxytocin preprotein and the oxytocin receptor expressed in human spermatozoa and is their mRNA expression different between normal semen samples and samples with at least one abnormal parameter? DESIGN: An in-vitro prospective study of 175 semen samples from Greek men, according to World Health Organization criteria, 2010. mRNA expression levels were compared between different categories of semen samples, classified according to their concentration, total number, motility and morphology. Immunohistochemistry was used to detect oxytocin preprotein and its receptor on spermatozoa smears. RESULTS: Compared with normal samples (normal motility and normal concentration), samples with at least one abnormal sperm parameter had statistically significantly lower oxytocin preprotein mRNA expression (P = 0.019) and higher oxytocin receptor mRNA expression levels (P < 0.001). Oligozoospermic samples had statistically significantly higher oxytocin preprotein mRNA expression levels (P = 0.002) and lower oxytocin receptor mRNA expression levels (P = 0.047). Asthenozoospermic samples had statistically significantly lower oxytocin preprotein mRNA expression levels (P < 0.001). Teratozoospermic samples had statistically significantly lower oxytocin preprotein mRNA expression levels (P = 0.049) and higher oxytocin receptor mRNA expression levels (P < 0.001). Oxytocin preprotein mRNA expression was positively associated with total progressive motility (P < 0.001) and negatively associated with the percentage of immotile spermatozoa (P = 0.001). Oxytocin receptor mRNA expression was negatively associated with the percentage of normal forms (P < 0.001). CONCLUSION: Oxytocin preprotein and oxytocin receptor mRNA expression in spermatozoa could be used as a novel and unbiased diagnostic tool for male infertility.


Assuntos
Infertilidade Masculina , Sêmen , Humanos , Masculino , Sêmen/metabolismo , Ocitocina/metabolismo , Receptores de Ocitocina/genética , Estudos Prospectivos , Motilidade dos Espermatozoides , Espermatozoides/metabolismo , Infertilidade Masculina/diagnóstico , RNA Mensageiro/metabolismo
3.
Medicina (Kaunas) ; 59(7)2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37512124

RESUMO

Background and Objectives: Sperm DNA fragmentation refers to any break in one or both of the strands of DNA in the head of a sperm. The most widely used methodologies for assessing sperm DNA fragmentation are the sperm chromatin structure assay (SCSA), the sperm chromatin dispersion assay (SCD), the single-cell gel electrophoresis assay (SCGE-comet), and the terminal-deoxynucleotidyl-transferase (TdT)-mediated dUTP nick end labelling (TUNEL) assay. The aim of this study was to compare the efficiency and sensitivity of the analysis of sperm DNA fragmentation using TUNEL via fluorescence microscopy, and flow cytometry. Materials and Methods: Semen samples were collected and analyzed for standard characteristics using light microscopy, and for sperm DNA fragmentation using both TUNEL via fluorescence microscopy, and flow cytometry. Results: There were no significant differences in the values of the sperm DNA fragmentation index (DFI) obtained when the analysis was performed using TUNEL or flow cytometry (p = 0.543). Spearman's correlation analysis revealed a significant negative correlation between sperm motility (%) and sperm DNA fragmentation (p < 0.01), as well as between sperm concentration and sperm DNA fragmentation (p < 0.05). The Mann-Whitney U test showed no significant difference in the DFI among couples with repeated implantation failure (RIF) and miscarriages (p = 0.352). Conclusions: Both methods (TUNEL via fluorescence microscopy, and flow cytometry) have a high efficiency and sensitivity in accurately detecting sperm DNA fragmentation, and can be effectively used to assess male fertility.


Assuntos
Análise do Sêmen , Sêmen , Masculino , Humanos , Fragmentação do DNA , Análise do Sêmen/métodos , Marcação In Situ das Extremidades Cortadas , Citometria de Fluxo/métodos , Motilidade dos Espermatozoides , Espermatozoides , Cromatina , Microscopia de Fluorescência
4.
Reprod Biomed Online ; 45(2): 219-233, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35680517

RESUMO

RESEARCH QUESTION: Are there any differences in viability, spindle abnormalities and mitochondrial and other organelle structures amongst embryos biopsied on day 3 versus day 5 before and after vitrification? DESIGN: A total of 240 day 3 biopsied embryos that developed to blastocysts but were rejected for transfer following preimplantation genetic testing for monogenic/single gene defects (PGT-M) (n = 115) or for aneuploidies (PGT-A) (n = 125) were divided into two groups: (i) 120 blastocysts treated for viability, spindle/chromosome configuration (SCC) analysis and transmission electron microscopy (TEM) analysis (fresh n = 20, n = 20, n = 20 and following vitrification/warming n = 20, n = 20, n = 20); (ii) 120 embryos were re-biopsied at the blastocyst stage and treated for viability, SCC and TEM analysis (fresh n = 20, n = 20, n = 20 and following vitrification/warming n = 20, n = 20, n = 20). Also, 60 vitrified blastocysts biopsied only on day 5 that were rejected for transfer following PGT-M (n = 6) or PGT-A (n = 54) were treated following warming for viability (n = 20), SCC (n = 20) and TEM analysis (n = 20). RESULTS: No differences were observed in SCC and ultrastructure between embryos biopsied on day 5 and day 3 but following vitrification higher numbers of abnormal spindles, distension of mitochondria, multivesicular bodies, lipofuscin droplets, altered cell junctions and occasionally excessive accumulation of glycogen granules were evident. The fresh day 3 biopsied group also had a lower incidence of damaged (propidium iodide-stained) cells compared with the fresh day 3+5 (P = 0.02) and the vitrified day 5 (P = 0.001) biopsied groups. CONCLUSIONS: Biopsies on day 5 and day 3 do not adversely affect embryo viability, SCC or ultrastructure, although following vitrification minimal embryo quality-dependent increases in spindle abnormalities and cell damage are observed.


Assuntos
Blastocisto , Vitrificação , Biópsia , Cromossomos , Criopreservação , Embrião de Mamíferos , Humanos
5.
Medicina (Kaunas) ; 58(10)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36295653

RESUMO

Background and objectives: Preimplantation genetic testing (PGT) offers patients the possibility of having a healthy baby free of chromosomal or genetic disorders. The present study focuses on the application of PGT for patients located in Northern Greece, investigating their clinical outcomes, their motives, and their overall physical and emotional experience during the treatment, in association with their socioeconomic background. Materials and Methods: Couples who underwent PGT for a monogenic condition (PGT-M, n = 19 cycles) or aneuploidy (PGT-A, n = 22 cycles) participated in the study. Fertilization, implantation, and pregnancy rates were recorded for all cycles. The couples were asked to fill in a questionnaire about the consultation they had received prior to treatment, their sociodemographic information, and the psychological impact PGT had on both the female and male partner. Results: The fertilization, implantation, and ongoing pregnancy rates for the PGT-M and PGT-A cycles were 81.3%, 70.6%, and 52.9%, and 78.2%, 64.3%, and 57.1%, respectively. Females experienced more intense physical pain than their male partners while psychological pain was encountered by both partners and occasionally in higher instances in males. No typical socioeconomic background of the patients referred for PGT in Northern Greece was noticed. Conclusion: PGT is an attractive alternative to prenatal diagnosis (PND), aiming to establisha healthy pregnancy by identifying and avoiding the transfer of chromosomally or genetically abnormal embryos to the uterus. Although the benefits of PGT were well-received by all patients undergoing the procedure, psychological pain was evident and especially prominent in patients with a previous affected child or no normal embryos for transfer. Holistic counseling is of utmost importance in order to make patients' experience during their journey to have a healthy baby less emotionally demanding and help them make the right choices for the future.


Assuntos
Diagnóstico Pré-Implantação , Feminino , Humanos , Masculino , Gravidez , Fertilização in vitro/métodos , Testes Genéticos/métodos , Dor , Diagnóstico Pré-Implantação/métodos , Estudos Retrospectivos , Classe Social
6.
Medicina (Kaunas) ; 58(2)2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35208497

RESUMO

Background and Objectives: Ankylosing spondylitis (AS) is a condition that affects 0.1% to 0.5% of the adult population. The aim of this case report was to investigate the possible effects of the drugs taken for treatment of AS as well as mRNA vaccination for COVID-19 on semen quality by performing a highly detailed analysis. Materials and Methods: Sperm characteristics were examined by light microscopy, DNA fragmentation (DFI) was analysed by flow cytometry and morphology was evaluated by transmission electron microscopy (TEM). Results: Semen analysis under therapy with (1) celecoxib and sulphasalazine showed: concentration 47 million/mL, 53% progressive motility, 7% normal morphology and 9.6% DFI, (2) Golimumab and before mRNA Vaccination showed: concentration 108 million/mL, 82% progressive motility, 1% normal morphology and 7.6% DFI, and (3) Golimumab and after 3 doses of mRNA Vaccination showed: concentration 142 million/mL, 85% progressive motility, 1% normal morphology and 6.8% DFI. TEM revealed head, neck and tail abnormalities, as well as the presence of cells with incomplete spermiogenesis white cells and phagocytes in the sample under therapy with celecoxib and sulphasalazine. Golimumab treatment lead to an increased incidence of elongated heads but in general reduced inflammation as no white cells were evident in TEM. Conclusion: The anti-inflamatory drugs celecoxib and sulphasalazine had no adverse effect on sperm quality as all parameters were within normal limits and the patient achieved under that treatment 2 pregnancies following natural conception that lead to the birth of a healthy boy and girl respectively. Anti-TNFa treatment with Golimumab exerted a negative effect on morphology but not on concentration, motility and DFI. After 3 doses of mRNA Vaccination, sperm concentration increased while motility, morphology and DFI remained similar to the values before vaccination suggesting no negative effect of the mRNA vaccine for COVID-19 on sperm quality.


Assuntos
COVID-19 , Infertilidade Masculina , Espondilite Anquilosante , Vacinas contra COVID-19 , Feminino , Humanos , Infertilidade Masculina/genética , Masculino , Gravidez , RNA Mensageiro , SARS-CoV-2 , Sêmen , Análise do Sêmen , Espondilite Anquilosante/tratamento farmacológico , Vacinação , Vacinas Sintéticas , Vacinas de mRNA
7.
Reprod Biomed Online ; 43(5): 833-842, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34593325

RESUMO

RESEARCH QUESTION: Are there any differences in viability and ultrastructure amongst embryos biopsied on Day 5 versus Day 3 following vitrification in open and closed systems and compared to fresh embryos? DESIGN: One hundred human embryos (40 blastocysts biopsied on Day 5 and subsequently vitrified in open or closed systems and 60 Day 3 biopsied embryos that developed to blastocysts but were rejected for transfer following preimplantation genetic testing for monogenic/single gene defects and for aneuploidies were either treated fresh [n = 20] or vitrified [n = 40] in open or closed systems) and following warming and culture for 4 h were subjected to viability staining with carboxyfluorescein-diacetate succinimidylester/propidium iodide or processed for transmission electron microscopy. RESULTS: No statistically significant differences were observed in the viability of human biopsied embryos following vitrification in open and closed systems. Compared to fresh embryos, vitrified ones had a higher incidence of damage (propidium iodide-stained cells) irrespective of the vitrification method (P = 0.005). These damaged cells were more prominent in Day 5 biopsied blastocysts and mainly located at the position of cutting. Characteristic lipofuscin droplets (representative of apoptosis) and a higher number of vacuoles and distension of mitochondria were also more evident in vitrified embryos, although this was not statistically assessed. CONCLUSIONS: Vitrification in open and closed systems does not adversely affect the viability and ultrastructure of Day 5 and Day 3 biopsied embryos as revealed by the minimal yet statistically significant cell damage observed. This damage may be compensated by the embryos, which in their attempt to fully recover following vitrification, potentially enable 'rescue' processes to eliminate it.


Assuntos
Biópsia , Sobrevivência Celular/fisiologia , Criopreservação/métodos , Embrião de Mamíferos/fisiologia , Embrião de Mamíferos/ultraestrutura , Corantes Fluorescentes , Blastocisto/ultraestrutura , Técnicas de Cultura Embrionária , Fluoresceínas , Humanos , Microscopia Eletrônica de Transmissão , Propídio , Succinimidas
8.
Reprod Biomed Online ; 42(1): 248-259, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33214084

RESUMO

RESEARCH QUESTION: Sex hormone-binding globulin (SHBG), androgen receptor (AR), LH beta polypeptide (LHB), progesterone receptor membrane component 1 (PGRMC1) and progesterone receptor membrane component 2 (PGRMC2) regulate follicle development and maturation. Their mRNA expression was assessed in peripheral blood mononuclear cells (PBMC) of normal and poor responders, during ovarian stimulation. DESIGN: Fifty-two normal responders and 15 poor responders according to the Bologna criteria were enrolled for IVF and intracytoplasmic sperm injection and stimulated with 200 IU of follitrophin alpha and gonadotrophin-releasing hormone antagonist. HCG was administered for final oocyte maturation. On days 1, 6 and 10 of stimulation, blood samples were obtained, serum hormone levels were measured, RNA was extracted from PBMC and real-time polymerase chain reaction was carried out to identify the mRNA levels. Relative mRNA expression of each gene was calculated by the comparative 2-DDCt method. RESULTS: Differences between mRNA levels of each gene on the same time point between the two groups were not significant. PGRMC1 and PGRMC2 mRNA levels were downregulated, adjusted for ovarian response and age. Positive correlations between PGRMC1 and AR (standardized beta = 0.890, P < 0.001) from day 1 to 6 and PGRMC1 and LHB (standardized beta = 0.806, P < 0.001) from day 1 to 10 were found in poor responders. PGRMC1 and PGRMC2 were positively correlated on days 6 and 10 in normal responders. CONCLUSIONS: PGRMC1 and PGRMC2 mRNA are significantly decreased during ovarian stimulation, with some potential differences between normal and poor responders.


Assuntos
Fármacos para a Fertilidade Feminina/administração & dosagem , Hormônio Foliculoestimulante Humano/administração & dosagem , Hormônio Liberador de Gonadotropina/análogos & derivados , Indução da Ovulação , Adulto , Feminino , Expressão Gênica/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/administração & dosagem , Humanos , Leucócitos Mononucleares/metabolismo , Hormônio Luteinizante Subunidade beta/metabolismo , Proteínas de Membrana/metabolismo , Ovário/efeitos dos fármacos , Estudos Prospectivos , Receptores Androgênicos/metabolismo , Receptores de Progesterona/metabolismo , Proteínas Recombinantes/administração & dosagem , Globulina de Ligação a Hormônio Sexual/metabolismo
9.
Medicina (Kaunas) ; 57(9)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34577870

RESUMO

Cryopreservation of human gametes and embryos as well as human reproductive tissues has been characterized as an essential process and aspect of assisted reproductive technology (ART). Notably, sperm cryopreservation is a fundamental aspect of cryopreservation in oncological patients or patients undergoing gonadotoxic treatment. Given that there is a risk of contamination or cross-contamination, either theoretical or real, during the procedures of cryopreservation and cryostorage, both the European Society for Human Reproduction and Embryology (ESHRE) and the American Society for Reproductive Medicine (ASRM) have provided updated guidelines for preventing or reducing the contamination risk of sexually transmitted viruses. Given the ongoing and worldwide COVID-19 pandemic, there is considerable interest in what measures should be taken to mitigate SARS-CoV-2 contamination during cryopreservation and cryostorage of semen samples. The SARS-CoV-2 virus is the virus that causes COVID-19, and whose transmission and infection is mainly aerosol-mediated. Several ART professional societies, including ESHRE and ASRM have proposed measures to mitigate the spread of the SARS-CoV-2 virus. Whether the proposed safety directives are enough to mitigate the possible SARS-CoV-2-contamination of sperm samples during cryopreservation or whether the policies should be re-evaluated will be discussed in this review. Additionally, insights regarding the possible impact of COVID-19 vaccination on the safety of sperm cryopreservation will be discussed.


Assuntos
COVID-19 , Criopreservação , SARS-CoV-2 , Preservação do Sêmen , COVID-19/complicações , Vacinas contra COVID-19 , Humanos , Masculino , Pandemias , Técnicas de Reprodução Assistida , Fatores de Risco , Sêmen/virologia , Manejo de Espécimes , Espermatozoides
10.
Hum Mol Genet ; 27(14): 2573-2585, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29688390

RESUMO

Aneuploidy is prevalent in human embryos and is the leading cause of pregnancy loss. Many aneuploidies arise during oogenesis, increasing with maternal age. Superimposed on these meiotic aneuploidies are frequent errors occurring during early mitotic divisions, contributing to widespread chromosomal mosaicism. Here we reanalyzed a published dataset comprising preimplantation genetic testing for aneuploidy in 24 653 blastomere biopsies from day-3 cleavage-stage embryos, as well as 17 051 trophectoderm biopsies from day-5 blastocysts. We focused on complex abnormalities that affected multiple chromosomes simultaneously, seeking insights into their formation. In addition to well-described patterns such as triploidy and haploidy, we identified 4.7% of blastomeres possessing characteristic hypodiploid karyotypes. We inferred this signature to have arisen from tripolar chromosome segregation in normally fertilized diploid zygotes or their descendant diploid cells. This could occur via segregation on a tripolar mitotic spindle or by rapid sequential bipolar mitoses without an intervening S-phase. Both models are consistent with time-lapse data from an intersecting set of 77 cleavage-stage embryos, which were enriched for the tripolar signature among embryos exhibiting abnormal cleavage. The tripolar signature was strongly associated with common maternal genetic variants spanning the centrosomal regulator PLK4, driving the association we previously reported with overall mitotic errors. Our findings are consistent with the known capacity of PLK4 to induce tripolar mitosis or precocious M-phase upon dysregulation. Together, our data support tripolar chromosome segregation as a key mechanism generating complex aneuploidy in cleavage-stage embryos and implicate maternal genotype at a quantitative trait locus spanning PLK4 as a factor influencing its occurrence.


Assuntos
Aneuploidia , Oogênese/genética , Proteínas Serina-Treonina Quinases/genética , Fuso Acromático/genética , Adolescente , Adulto , Blastocisto/patologia , Blastômeros/patologia , Segregação de Cromossomos/genética , Feminino , Testes Genéticos , Variação Genética , Genótipo , Humanos , Cariótipo , Idade Materna , Pessoa de Meia-Idade , Mitose/genética , Gravidez , Fuso Acromático/patologia
11.
Zygote ; 27(3): 153-159, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31060631

RESUMO

SummaryThe aim of this study was to investigate the effects of zona drilling and biopsy on day 3 followed by vitrification on day 5 on the cytoskeleton and development of human embryos, by analysing survival rates and spindle and chromosome configurations by fluorescence and confocal laser scanning microscopy in human biopsied and non-biopsied embryos. In total, 98 human blastocysts (50 non-biopsied and 48 following biopsy on day 3) were vitrified on day 5 using either a commercial dimethyl sulphoxide (DMSO)-free vitrification kit or increasing concentrations of DMSO/EG (5%/5-10%/10-20%/20%). Following warming, the blastocysts were allowed to recover in culture for 24 h and were immunostained with α-tubulin, acetylated tubulin, and/or γ-tubulin antibodies in combination with 4',6-diamidino-2-phenylindole (DAPI). Labelled embryos were examined by both fluorescence and confocal laser scanning microscopy. The survival rates following warming (92% non-biopsied vs 83.3% biopsied) and the incidence of normal spindle chromosome configurations was not statistically different between the two groups (65.2% non-biopsied vs 59.2% biopsied, P>0.05). The incidence of spindle abnormalities including multipolarity, chromosome lagging, congression failure and chromosome bridging were also similar between the two groups (P>0.05). This study is the first to compare the incidence of cytoskeletal abnormalities in biopsied and non-biopsied human embryos following vitrification. We conclude that there was no significant difference in the survival rates and the incidence of spindle abnormalities between the two groups.


Assuntos
Blastocisto/citologia , Aberrações Cromossômicas/embriologia , Citoesqueleto/metabolismo , Embrião de Mamíferos/citologia , Microscopia Confocal/métodos , Vitrificação , Biópsia , Blastocisto/metabolismo , Sobrevivência Celular , Técnicas de Cultura Embrionária , Transferência Embrionária/estatística & dados numéricos , Embrião de Mamíferos/embriologia , Desenvolvimento Embrionário , Humanos , Fatores de Tempo , Tubulina (Proteína)/metabolismo
12.
Reprod Biomed Online ; 37(5): 573-580, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30539719

RESUMO

The use of testicular spermatozoa in men without azoospermia has been proposed as a means to increase the chances of pregnancy following assisted reproductive treatment. The purpose of this systematic review is to assess whether clinical outcomes are better when testicular rather than ejaculated spermatozoa are used for intracytoplasmic sperm injection in patients with abnormal semen parameters without azoospermia. A literature search identified four eligible studies out of 757 initially found. In a prospective study in men with high DNA fragmentation index (DFI) and oligozoospermia, the probability of live birth was significantly higher with testicular compared to ejaculated spermatozoa (risk ratio [RR]: 1.75, 95% confidence interval [CI]: 1.14-2.70). This was not the case in a retrospective study in men with high DFI only (RR: 2.36, 95% CI: 0.98-5.68). Clinical pregnancy rates were similar in a randomized controlled trial in men with asthenozoospermia with or without teratozoospermia (RR: 2.85, 95% CI: 0.76-10.69) and in a retrospective study in men with isolated asthenozoospermia (RR: 1.09, 95% CI: 0.56-2.14). Currently, there is limited, low-quality evidence suggesting that a higher probability of pregnancy might be expected using testicular rather than ejaculated spermatozoa, only in men with high DFI and oligozoospermia.


Assuntos
Injeções de Esperma Intracitoplásmicas/métodos , Recuperação Espermática , Adulto , Fragmentação do DNA , Ejaculação , Feminino , Humanos , Masculino , Oligospermia , Gravidez , Taxa de Gravidez , Análise do Sêmen , Testículo
13.
Zygote ; 25(1): 75-84, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27923412

RESUMO

Vitrification is widely used to cryopreserve supernumerary embryos following in vitro fertilization (IVF). The mouse model was used to investigate the effects of vitrification on blastomere viability, using viability markers, and on the cytoskeleton, by analysing spindle/chromosome configurations, using confocal scanning microscopy. Ninety cleavage and morula stage dimethyl sulphoxide (DMSO)/EG vitrified mouse embryos were either processed immediately following warming for viability assessment by labelling with the fluorescent markers carboxyfluorescein-diacetate succinimidylester (CFSE) and propidium iodide (PI) or were cultured to the blastocyst stage and immunostained with α-tubulin antibody to visualize microtubules and DAPI or PI to visualize DNA. Sixty-five fresh embryos were also used as the control. Vitrified embryos showed high survival rates following warming, but they had a higher incidence of damaged blastomeres compared with fresh embryos. Most mitotic spindles examined in all groups were normal, but multivariable analysis revealed that the proportion of abnormal spindles was significantly higher in vitrified/warmed embryos (P < 0.05). This study is the first to examine the immediate effects of vitrification on blastomere viability, using fluorescent markers and shows that although vitrification results in a higher incidence of damaged blastomeres, vitrified embryos may compensate for this limited number of damaged/abnormal cells, as development to the blastocyst stage was not compromised.


Assuntos
Blastômeros/citologia , Blastômeros/fisiologia , Embrião de Mamíferos/citologia , Vitrificação , Animais , Blastocisto/patologia , Criopreservação/métodos , Citoesqueleto , Dimetil Sulfóxido , Embrião de Mamíferos/fisiologia , Feminino , Masculino , Camundongos Endogâmicos C57BL , Mórula , Fuso Acromático , Tubulina (Proteína)/metabolismo
14.
Cell Mol Neurobiol ; 36(5): 701-12, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26239244

RESUMO

Hypoxia is the lack of sufficient oxygenation of tissue, imposing severe stress upon cells. It is a major feature of many pathological conditions such as stroke, traumatic brain injury, cerebral hemorrhage, perinatal asphyxia and can lead to cell death due to energy depletion and increased free radical generation. The present study investigates the effect of hypoxia on the unfolded protein response of the cell (UPR), utilizing a 16-h oxygen-glucose deprivation protocol (OGD) in a PC12 cell line model. Expression of glucose-regulated protein 78 (GRP78) and glucose-regulated protein 94 (GRP94), key players of the UPR, was studied along with the expression of glucose-regulated protein 75 (GRP75), heat shock cognate 70 (HSC70), and glyceraldehyde 3-phosphate dehydrogenase, all with respect to the cell death mechanism(s). Cells subjected to OGD displayed upregulation of GRP78 and GRP94 and concurrent downregulation of GRP75. These findings were accompanied with minimal apoptotic cell death and induction of autophagy. The above observation warrants further investigation to elucidate whether autophagy acts as a pro-survival mechanism that upon severe and prolonged hypoxia acts as a concerted cell response leading to cell death. In our OGD model, hypoxia modulates UPR and induces autophagy.


Assuntos
Autofagia/fisiologia , Glucose/metabolismo , Oxigênio/metabolismo , Resposta a Proteínas não Dobradas/fisiologia , Animais , Apoptose/efeitos dos fármacos , Hipóxia Celular , Sobrevivência Celular , Chaperona BiP do Retículo Endoplasmático , Neurônios/metabolismo , Células PC12 , Ratos
15.
Reprod Biomed Online ; 31(5): 625-32, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26387934

RESUMO

The aim of this study was to evaluate whether prolongation of the time interval between HCG administration and oocyte retrieval, from 36 h to 38 h, affects oocyte retrieval rate in women undergoing ovarian stimulation with gonadotrophins and GnRH antagonists for IVF. One hundred and fifty-six normo-ovulatory women were randomized to have oocyte retrieval performed 36 h (n = 78) or 38 h (n = 78) following HCG administration. Oocyte retrieval rate was defined as number of cumulus-oocyte-complex (COC) retrieved/follicle ≥ 11 mm present on day of HCG administration. No significant differences were observed between the groups regarding baseline characteristics. Moreover, no significant difference was observed between the groups regarding oocyte retrieval rate (difference: + 1.2%, 95% CI for difference between medians: -4.5 to +12.1). The median (95% CI for the median) was not significantly different between the groups regarding number of cumulus-oocyte-complexes (COCs) retrieved: 5.5 (5.0-7.0) versus 6.0 (5.0-6.2), respectively, and fertilization rates: 57.7% (50.0-66.7) versus 50.0% (44.8-65.5), respectively. Live birth rates were similar between the groups (20.5% versus 16.7%, RD: + 3.8%, 95% CI: -8.5 to +16.1, respectively). Prolongation of time interval between HCG administration and oocyte retrieval from 36 h to 38 h does not affect oocyte retrieval rate.


Assuntos
Gonadotropina Coriônica/administração & dosagem , Fármacos para a Fertilidade Feminina/administração & dosagem , Fertilização in vitro/métodos , Recuperação de Oócitos/métodos , Adulto , Gonadotropina Coriônica/uso terapêutico , Feminino , Fármacos para a Fertilidade Feminina/uso terapêutico , Humanos , Indução da Ovulação , Gravidez , Taxa de Gravidez , Método Simples-Cego , Fatores de Tempo
16.
Cureus ; 16(3): e56936, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38665724

RESUMO

Poland syndrome is a congenital anatomical anomaly, characterised by partial or total aplasia of one side of the body causing abnormalities affecting the chest, shoulder, and upper limb. The exact mechanism that leads to this syndrome is unknown, but an abnormality in the vasculature formation or interruption of the blood supply of the subscapular artery and its branches early in development may be the main cause. Depending on the underlying mechanism, the syndrome has several expressions with some hardly being detectable and others not even being compatible with life. Here, we present a case of pregnancy from an assisted reproductive technology (ART) cycle with in vitro maturation (IVM) and rescue intra cytoplasmic sperm injection (ICSI), which resulted in the in-utero death of the foetus. The subsequent necropsy revealed a variation of Poland syndrome.

17.
Syst Biol Reprod Med ; 69(4): 288-295, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37178126

RESUMO

It is well known that various human papillomavirus (HPV) genotypes are present in semen specimens. Also, it has been demonstrated that sperm parameters are negatively affected when HPV infection is present in the sperm sample. Besides all these, the effect of cryopreservation on HPV sensitivity and resistance is not known. The aim of the present study is to evaluate first the prevalence of HPV and secondly to elucidate whether cryopreservation of sperm HPV-positive samples has any effect on the viability of HPV. For this purpose, a cohort of 78 sperm specimens was used from a respective number of patients. After giving informed consent, semen analysis was performed. Each sperm sample was divided into four equal aliquots. The first one (fresh) was evaluated for the prevalence of HPV, while the other three aliquots were cryopreserved by adding an equal quantity of cryoprotectant and plunged into the LN. Each of the three aliquots was thawed 3, 6, and 12 months later, respectively, so as to evaluate whether there is a time-resistance period of HPV prevalence. HPV infection was found to be in eleven sperm samples, demonstrating a 14.1% (11/78) HPV prevalence. Among the HPV-positive samples, six of them were high-risk and the remaining were low-risk genotypes. Moreover, the high-risk fresh samples demonstrated higher motility values than the low-risk samples (60% ± 2.7 vs 45.6% ± 3.7, p < .05), while semen volume in the high-risk samples was significantly lower than the respective volume in the low-risk samples (2.26 ± 0.2ml vs 3.5 ± 0.6ml, p < .05). Interestingly, cryopreservation of the HPV-positive samples resulted in the sustainability and time-resistance of HPV in all high-risk HPV-positive samples, something that was not the case with the low-risk HPV-positive samples. Conclusively, sperm samples infected with high-risk HPV, demonstrate lower sperm parameters and time-resistance activity during cryopreservation.


Assuntos
Infecções por Papillomavirus , Preservação do Sêmen , Humanos , Masculino , Sêmen , Motilidade dos Espermatozoides , Preservação do Sêmen/métodos , Espermatozoides , Criopreservação/métodos
18.
Hum Reprod ; 27(1): 106-13, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22028018

RESUMO

BACKGROUND: Vitrification of human blastocysts is being used increasingly to cryopreserve supernumerary embryos following IVF. In this study, we investigate the effects of aseptic vitrification on the cytoskeleton and development of human blastocysts, by analysing survival rates and spindle and chromosome configurations by fluorescence and confocal laser scanning microscopy. METHODS: A total of 55 fresh blastocysts and 55 day 5 dimethylsulphoxide/ethylene glycol vitrified blastocysts, which were allowed to remain in culture for 24 h post-warming, were rapidly fixed in ice cold methanol, and immunostained with an a-tubulin antibody to visualize microtubules in combination with antibodies against acetylated tubulin (to visualize spindles, poles and mid bodies), gamma tubulin (to identify spindle poles) and 4(6-diamidino-2-phenylindole) to visualize DNA. RESULTS: In total, 213 spindles were analysed in the control (fresh) group of which 183/213 (85.9%) were normal, 20/213 (9.4%) were abnormally shaped, 9/213 (4.2%) were multipolar and 1/213 (0.5%) was monopolar. A total of 175 spindles were analysed in the vitrified group, of which 120/175 (68.6%) were normal, 39/175 (22.3%) were abnormally shaped, 10/175 (5.7%) were multipolar and 6/175 (3.4%) were monopolar. The incidence of multipolar spindles was similar in the two groups, but the level of abnormally shaped spindles, often associated with chromosome lagging, or congression failure, was significantly higher in the vitrified group compared with the fresh group (P< 0.05). CONCLUSIONS: The high survival rate following thawing and the large proportion of normal spindle/chromosome configurations suggests that vitrification at the blastocyst stage on Day 5 does not adversely affect the development of human embryos and the ability of spindles to form and continue normal cell divisions. However, there was a significantly higher incidence of abnormal spindles in the vitrified group compared with the fresh group, notably of spindles with a focused and an unfocused pole as well as chromosome bridging and disorganized middle spindle fibres at telophase. Further investigation is warranted to elucidate the mitotic stages that are more vulnerable to damage during vitrification, the fate of the abnormal spindles and any potential effects that may be reflected on the chromosomal constitution of the developing blastocysts.


Assuntos
Blastocisto/citologia , Citoesqueleto/patologia , Microscopia Confocal/métodos , Ciclo Celular , Divisão Celular , Sobrevivência Celular , Citoesqueleto/metabolismo , DNA/metabolismo , Dimetil Sulfóxido/química , Etilenoglicol/química , Feminino , Humanos , Oócitos/citologia , Ovário/citologia , Fuso Acromático , Tubulina (Proteína)/metabolismo , Vitrificação
19.
J Dev Biol ; 9(4)2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34842724

RESUMO

Telomeres promote genome integrity by protecting chromosome ends from the activation of the DNA damage response and protecting chromosomes from the loss of coding sequences due to the end replication problem. Telomere length (TL) is progressively shortened as age progresses, thus resulting in cellular senescence. Therefore, TL is in strong adverse linear correlation with aging. Mounting evidence supports the notion that telomeres and male/female infertility are in a close relationship, posing the biology of telomeres as a hot topic in the era of human-assisted reproduction. Specifically, the length of sperm telomeres is gradually increasing as men get older, while the telomere length of the oocytes seems not to follow similar patterns with that of sperm. Nonetheless, the telomere length of the embryos during the cleavage stages seems to have a paternal origin, but the telomere length can be further extended by telomerase activity during the blastocyst stage. The latter has been proposed as a new molecular biomarker with strong predictive value regarding male infertility. As far as the role of telomeres in assisted reproduction, the data is limited but the length of telomeres in both gametes seems to be affected mainly by the cause of infertility rather than the assisted reproductive therapy (ART) procedure itself. The present review aims to shed more light into the role of telomeres in human embryological parameters, including gametes and embryos and also presents opinions regarding the association between telomeres and in vitro fertilization (IVF).

20.
Int J Reprod Biomed ; 19(3): 217-226, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33842818

RESUMO

BACKGROUND: Recent scientific data support that the mode of conception and delivery may influence epigenetic regulation and therefore embryo development. Octamer-binding transcription factor 4-B1 (OCT4B1), a novel variant of OCT4 with yet unknown biological function, is suggested to have a potential role in mediating cellular stress response. Furthermore, Insulinlike Growth Factor 2 (IGF2), Mesoderm-specific Transcript (MEST) and paternally expressed gene 10 (PEG10) are genes known as imprinted and are regulated via means of epigenetic regulation. The influence of delivery mode and conception on epigenetic regulation is an active research field. OBJECTIVE: Our aim was to correlate the expression level of Oct4B1 and the expression and methylation level of IGF2, MEST, and PEG10 imprinted genes with the mode of delivery and conception in the umbilical cord blood of newborns. MATERIALS AND METHODS: Samples of umbilical cord blood from infants born after vaginal delivery, caesarean section (CS) with the infant in cephalic position and CS due to breech position were examined. Furthermore, the investigation included infants conceived through means of assisted reproductive technology. RESULTS: No statistically significant differences were found in mRNA expression levels between different modes of conception and delivery (p = 0.96). Oct4B1, IGF2, MEST, and PEG10 expression levels do not seem to be significantly affected by different modes of conception and delivery. CONCLUSION: These results indicate that the expression and methylation patterns of Oct4B1, IGF2, MEST and PEG10 in umbilical cord blood are not affected by the conception and delivery mode.

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