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1.
Biophys Rev ; 15(5): 1223-1232, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37975014

RESUMO

Cryopreservation of male gametes is one of the most important methods of assisted reproductive technologies, which allows preserving gametes for research or further use. However, the fertilizing ability of spermatozoa after cryopreservation decreases by 30-70%, which makes it urgent to search for new substances with cryoprotective properties. The review considers the main causes of cell damage during cryopreservation. The relevance of methods for assessing the formation of crystals and the physicochemical properties of cryoprotective media depending on various compositions is discussed. The problem of stabilization of the spermatozoa membrane during cryopreservation is considered. A possible solution to the problem of membrane integrity may consist in modification of the basic cryoprotective media with yolk emulsion or development of methods for saturation of the membrane phospholipid layer with cholesterol.

2.
Best Pract Res Clin Obstet Gynaecol ; 85(Pt B): 134-148, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35216907

RESUMO

Two observational studies in the Russian Federation described patient demographics/clinical decision for treatment with recombinant human follicle-stimulating hormone:recombinant human luteinizing hormone (r-hFSH:r-hLH) 2:1 combination for ovarian stimulation (OS) during assisted reproductive technology (ART) and outcomes, respectively. The first (prospective) study enrolled 500 patients. After post-hoc regrouping to assign patients to discrete groups, 378 (75.6%) met the local Russian label for an r-hFSH:r-hLH 2:1 combination, 105 (21%) were treated according to other physician preference, and 17 (3.4%) met only the ESHRE Bologna criteria for a poor ovarian response. The clinical pregnancy rate per cycle was 30.4%. A total of 158/175 (90.3%) women achieving clinical pregnancy in the prospective study participated in the second (retrospective) study. The live birth rate per cycle was 25.8%. No new safety concerns were reported. These results support the use of the r-hFSH:r-hLH 2:1 combination in patients with a poor/suboptimal response to OS for ART treatment in the Russian Federation.


Assuntos
Hormônio Foliculoestimulante Humano , Hormônio Luteinizante , Feminino , Humanos , Masculino , Gravidez , Hormônio Foliculoestimulante/uso terapêutico , Hormônio Foliculoestimulante Humano/uso terapêutico , Hormônio Luteinizante/uso terapêutico , Indução da Ovulação/métodos , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Técnicas de Reprodução Assistida , Estudos Retrospectivos
3.
Int Wound J ; 19(4): 871-887, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34713964

RESUMO

A growing number of studies report dermal malignancies mimicking diabetic foot ulcers (DFUs). We reviewed clinical cases reporting malignant tumours misdiagnosed to be DFU aiming to identify factors contributing to misdiagnosis. We systematically searched in PubMed for clinical cases reporting on misdiagnosis of DFU in patients with cancer. A chi-square analysis was conducted to show the link between the incidence of initial DFU misdiagnosis and patient age, gender and wound duration. Lesions misdiagnosed to be DFU were subsequently diagnosed as melanoma (68% of the cases), Kaposi's sarcoma (14%), squamous cell carcinoma (11%), mantle cell lymphoma, and diffuse B-cell lymphoma (both by 4%). Older age (≥65 years) was associated with a significantly increased risk of malignancy masked as DFU (OR: 2.452; 95% CI: 1.132 to 5.312; P value = .019). The risk of such suspicion in older patients (age ≥ 65 years) was 145% higher than in younger patients (age < 65 years). Clinicians should maintain a high level of awareness towards potentially malignant foot lesions in elderly patients with diabetes (age ≥ 65).


Assuntos
Diabetes Mellitus , Pé Diabético , Úlcera do Pé , Neoplasias Cutâneas , Adulto , Idoso , Pé Diabético/complicações , Erros de Diagnóstico , , Humanos , Incidência , Neoplasias Cutâneas/complicações , Neoplasias Cutâneas/diagnóstico
4.
Int J Mol Sci ; 22(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34360784

RESUMO

In human spermatozoa, calcium dynamics control most of fertilization events. Progesterone, present in the female reproductive system, can trigger several types of calcium responses, such as low-frequency oscillations. Here we aimed to identify the mechanisms of progesterone-induced calcium signaling in human spermatozoa. Progesterone-induced activation of fluorophore-loaded spermatozoa was studied by fluorescent microscopy. Two computational models were developed to describe the spermatozoa calcium responses: a homogeneous one based on a system of ordinary differential equations and a three-dimensional one with added space dimensions and diffusion for the cytosolic species. In response to progesterone, three types of calcium responses were observed in human spermatozoa: a single transient rise of calcium concentration in cytosol, a steady elevation, or low-frequency oscillations. The homogenous model provided qualitative description of the oscillatory and the single spike responses, while the three-dimensional model captured the calcium peak shape and the frequency of calcium oscillations. The model analysis demonstrated that an increase in the calcium diffusion coefficient resulted in the disappearance of the calcium oscillations. Additionally, in silico analysis suggested that the spatial distribution of calcium signaling enzymes governs the appearance of calcium oscillations in progesterone-activated human spermatozoa.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Simulação por Computador , Modelos Biológicos , Progesterona/farmacologia , Espermatozoides/enzimologia , Humanos , Masculino , Microscopia de Fluorescência , Espermatozoides/citologia
5.
Front Bioeng Biotechnol ; 9: 591775, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34222206

RESUMO

The long-term co-culture of mouse embryonic stem cells (mESC) with rat endothelial cells (EC) was tested for contact differentiation into the endothelial lineage. Serial passaging of rat ECs mixed with mESC in ratio 10:1 resulted in the emergence of a homogeneous cell population expressing mouse endothelial surface markers CD102, CD29, CD31. Rat endothelial surface marker RECA-1 completely disappeared from the co-cultured population after 2 months of weekly passaging. Co-incubation of mESC with rat ECs without cell-to-cell contact did not result in the conversion of mESC into ECs. After co-cultivation of adult mesenchymal stem cells from human endometrium (eMSC) with pre-hepatocyte-like cells of human hepatocarcinoma Huh7 the resulting co-culture expressed mature liver markers (oval cell antigen and cytokeratin 7), none of which were expressed by any of co-cultivated cultures, thus proving that even an immature (proliferating) pre-hepatocyte-like line can induce hepatic differentiation of stem cells. In conclusion, we have developed conditions where long-term co-proliferation of embryonic or adult SC with fully or partially differentiated cells results in stem cell progeny expressing markers of target tissue. In the case of endothelial differentiation, the template population quickly disappeared from the resulted culture and the pure endothelial population of stem cell progeny emerged. This approach demonstrates the expected fate of stem cells during various in vivo SC-therapies and also might be used as an effective in vitro differentiation method to develop the pure endothelium and, potentially, other tissue types of desirable genetic background.

6.
J Assist Reprod Genet ; 38(10): 2563-2574, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33864207

RESUMO

Although in vitro culture of human embryos is a crucial step in assisted reproduction, the lack of focused research hampers worldwide standardisation and consistent outcomes. Only 1.2% of research papers published in five leading journals in human reproduction in 2019 focused on in vitro culture conditions, creating the impression that the optimisation process has approached its limits. On the other hand, in vitro culture of mammalian embryos is based on old principles, while there is no consensus on basic issues as density, time, medium change, gas atmosphere and small technical details including the way of drop preparation. This opinion paper aims to highlight and analyse the slow advancement in this field and stimulate research for simple and affordable solutions to meet the current requirements. A possible way for advancement is discussed in detail. Selection of embryos with the highest developmental competence requires individual culture and modification of the widely used "drop under oil" approach. Current use of three-dimensional surfaces instead of large flat bottoms is restricted to time-lapse systems, but these wells are designed for optical clarity, not for the needs of embryos. The size and shape of the original microwells (Well of the Well; WOW) offer a practical and straightforward solution to combine the benefits of communal and individual incubation and improve the overall quality of cultured embryos.


Assuntos
Blastocisto/citologia , Técnicas de Cultura Embrionária/métodos , Técnicas de Cultura Embrionária/normas , Embrião de Mamíferos/citologia , Desenvolvimento Embrionário , Fertilização in vitro/métodos , Meios de Cultura , Humanos
7.
Prenat Diagn ; 41(3): 368-375, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33140416

RESUMO

OBJECTIVES: Due to the maternally-inherited nature of mitochondrial DNA (mtDNA), there is a lack of information regarding fetal mtDNA in the plasma of pregnant women. We aim to explore the presence and topologic forms of circulating fetal and maternal mtDNA molecules in surrogate pregnancies. METHODS: Genotypic differences between fetal and surrogate maternal mtDNA were used to identify the fetal and maternal mtDNA molecules in plasma. Plasma samples were obtained from the surrogate pregnant mothers. Using cleavage-end signatures of BfaI restriction enzyme, linear and circular mtDNA molecules in maternal plasma could be differentiated. RESULTS: Fetal-derived mtDNA molecules were mainly linear (median: 88%; range: 80%-96%), whereas approximately half of the maternal-derived mtDNA molecules were circular (median: 51%; range: 42%-60%). The fetal DNA fraction of linear mtDNA was lower (median absolute difference: 9.8%; range: 1.1%-27%) than that of nuclear DNA (median: 20%; range: 9.7%-35%). The fetal-derived linear mtDNA molecules were shorter than the maternal-derived ones. CONCLUSION: Fetal mtDNA is present in maternal plasma, and consists mainly of linear molecules. Surrogate pregnancies represent a valuable clinical scenario for exploring the biology and potential clinical applications of circulating mtDNA, for example, for pregnancies conceived following mitochondrial replacement therapy.


Assuntos
DNA Mitocondrial/genética , Feto/anormalidades , Mães Substitutas/estatística & dados numéricos , Adulto , DNA Mitocondrial/sangue , Feminino , Feto/fisiopatologia , Humanos , Herança Materna/genética , Moscou/epidemiologia , Plasma/microbiologia , Gravidez
8.
Reprod Biomed Online ; 39(5): 745-749, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31530444

RESUMO

RESEARCH QUESTION: Does complete mechanical removal of the zona pellucida modify the outcome of transfer of vitrified-warmed human blastocysts? DESIGN: In a prospective randomized controlled study, 419 couples were allocated to either zona pellucida-free (n = 209) or zona intact (n = 210) vitrified-warmed embryo transfer. Main outcome measures included clinical pregnancy, implantation and ongoing pregnancy rates. RESULTS: Transfer of zona pellucida-free blastocysts resulted in clinical pregnancy, implantation and ongoing pregnancy rates (35,9%, 33,9% and 32,1%, respectively), similar to those achieved with zona intact control embryos (39%, 36,4% and 33,1%, respectively). CONCLUSION: Total mechanical removal of the zona pellucida did not affect the tested parameters of clinical outcomes.


Assuntos
Blastocisto/citologia , Transferência Embrionária/métodos , Injeções de Esperma Intracitoplásmicas/métodos , Zona Pelúcida , Adulto , Criopreservação , Implantação do Embrião , Feminino , Humanos , Gravidez , Taxa de Gravidez , Progesterona/metabolismo , Estudos Prospectivos , Resultado do Tratamento , Vitrificação , Adulto Jovem
9.
Eur J Obstet Gynecol Reprod Biol ; 241: 6-12, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31400644

RESUMO

OBJECTIVE: The aim of the present study was to investigate the therapeutic equivalence between the follitropin alpha biosimilar and the reference medication in women undergoing assisted reproductive technologies (ART). STUDY DESIGN: This multicenter, randomized (1:1), embryologist-blinded, parallel-group, comparative phase III study involved 110 women aged 20-35 years old with tubal and/or male factors of infertility. All of the subjects underwent controlled ovarian hyperstimulation (COH) using a gonadotropin-releasing hormone antagonist (GnRH-ant) protocol. Over the 5-day fixed-dose regimen, the women received 150 IU/day of follitropin alpha biosimilar (n = 55) or original follitropin alpha (n = 55), followed by dose adaptation. The primary endpoint for assessing the therapeutic equivalence was the number of retrieved oocytes using a pre-determined clinical equivalence margin of ± 3.4 oocytes. RESULTS: Similar numbers of oocytes were retrieved in both groups: 12.16 ± 7.28 in the follitropin alpha biosimilar group and 11.62 ± 6.29 in the original follitropin alpha group, with mean difference of 0.546 ± 1.297 oocytes (95% confidence interval [CI]: -2.026, 3.116), p = 0.002 (intention-to-treat [ITT] population). Additionally, no statistically significant differences were found for secondary endpoints: the onset of biochemical (34.7% and 36.7%, p = 0.883), clinical pregnancy (26.5% and 32.7%, p = 0.507), delivery (26.5% and 24.5%, p = 0.817) and take-home baby rate (28.6% and 26.5%, p = 0.816) for the follitropin biosimilar and original follitropin groups (per-protocol [PP] population). Ovarian hyperstimulation syndrome was observed in subjects with a positive pregnancy test in 0% and 3.64% of cases and after triggering ovulation in 7.27% and 3.64% for the follitropin biosimilar and original follitropin groups, respectively. CONCLUSIONS: This study demonstrated similar therapeutic equivalence and safety profiles between the follitropin alpha biosimilar and the reference follitropin in women who underwent COH in GnRH-ant cycles. TRIAL REGISTRATION NUMBER: 1. Name of the registry: ClinicalTrials.gov. TRIAL REGISTRATION NUMBER: NCT03088137. Date of registration: 02.03.2017, retrospectively registered. Trial conducted between 08.02.2017 and 17.08.2018, the date of enrollment of the first participant - 08.02.2017. 2. Name of the registry: Russian Ministry of Health, grls.rosminzdrav.ru. TRIAL REGISTRATION NUMBER: RCT 754. Date of registration: 26.10.2016, prospectively registered.


Assuntos
Medicamentos Biossimilares , Hormônio Foliculoestimulante Humano , Indução da Ovulação/estatística & dados numéricos , Adulto , Feminino , Humanos , Indução da Ovulação/métodos , Gravidez , Taxa de Gravidez , Proteínas Recombinantes
10.
J Acoust Soc Am ; 142(4): 1990, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-29092617

RESUMO

The paper analyzes the experimental data obtained in a comprehensive experiment aimed at identifying the regularities of transmitted hydroacoustic signal transformations at the shelf of decreasing depth. The 33 Hz harmonic hydroacoustic signals were generated at the shelf of the Sea of Japan by a low-frequency source. Distribution of the transmitted energy at vertical sounding from the surface to the bottom was studied at different shelf points with Bruel & Kjaer 8104 hydrophone. At the shore, the transformed seismo-acoustic signals were received by a 52.5 m shore laser strainmeter. The experiments showed that about 22% of the transmitted energy was transformed into the energy of hydroacoustic waves propagating in the water. About 72% of hydroacoustic wave energy, in turn, was transformed into the energy of R-waves, which were registered by the shore laser strainmeter. Other regularities of hydroacoustic signals distribution with 33 Hz frequency over the V-shaped shelf are identified.

11.
J Assist Reprod Genet ; 29(10): 1141-5, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22772454

RESUMO

OBJECTIVE: To evaluate the level of ribosomal RNA (rRNA) in cumulus cells (CCs) from women with polycystic ovary syndrome (PCOS) undergoing ICSI. MATERIALS AND METHODS: The study population included three healthy oocyte donors (control) and three patients with PCOS. RNA expression in CCs was assessed using quantitative real-time PCR assay to measure the pre-rRNA transcripts (5'ETS region), 18 S, 5.8 S and 28 S rRNA. RESULTS: The level of 18 S rRNA is 3.9 times higher (p = 0.036) and the level of 5.8 S rRNA is 2.9 times higher (p = 0.049) in CCs of PCOS patients than in CCs of healthy women. The fold change in expression of 28 S rRNA in CCs of PCOS patients also exceeds that in the control group, but did not reach a statistical significance (p = 0.342). CONCLUSION: Our observations support the idea that CCs of PCOS patients contain comparatively more ribosomes that CCs of healthy oocyte donors that may indicate a higher proliferation rate or up-regulated translation of protein factors in ССs of PCOS patients.


Assuntos
Células do Cúmulo/fisiologia , Síndrome do Ovário Policístico/genética , RNA Ribossômico/genética , Adulto , Estudos de Casos e Controles , Feminino , Expressão Gênica , Humanos , RNA Ribossômico 18S , RNA Ribossômico 28S , RNA Ribossômico 5,8S , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Injeções de Esperma Intracitoplásmicas
12.
Biomacromolecules ; 8(7): 2258-61, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17583947

RESUMO

Interaction of polyadenylic acid, poly(A), with stearic acid Langmuir-Blodgett (LB) monolayer was studied in different electrolyte surroundings. For this purpose LB films of stearic acid, transferred on the mica substrate from poly(A) containing subphase, were analyzed with atomic force microscopy (AFM). The density of polynucleotides surface coverage is ruled by the monovalent electrolyte concentration in the subphase that is in good agreement with previous results. Divalent cations in the subphase are needed to stabilize poly(A) molecules on the surface through formation of "salt bridges". At the very low divalent electrolyte concentration polynucleotides adsorb on the LB film to domains in which the effect of self-assembly is observed. Increase of divalent electrolyte concentration leads to the loss of this orientation effect. The explanation of this effect is proposed.


Assuntos
Polinucleotídeos/química , Ácidos Esteáricos/química , Adsorção , Cátions Bivalentes , Microscopia de Força Atômica
13.
Cryobiology ; 54(3): 305-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17451668

RESUMO

Vitrification of laser treated human blastocysts using reduced concentrations of permeable cryoprotectants was carried out by submerging cut standard straws (CSS) into liquid nitrogen. The CSS were made by cutting a standard 0.25 ml straw at an angle of approximately 45 degrees . After laser assisted hatching, 6 day blastocysts (n=250) were loaded into droplets of approximately 0.75 microl in the CSS and were either plunged directly into liquid nitrogen or first encased in a standard 0.5 ml straw (aseptic technique) before being vitrified. Permeable cryoprotectants (ethylene glycol+Me(2)SO) at concentrations of 15% and 20% v:v were tested for their effect on post warming re-expansion and post transfer pregnancy rates. Our results indicate that the use of reduced concentrations of cryoprotectants and aseptic packaging of blastocysts did not have any statistically significant impact on the study outcomes.


Assuntos
Blastocisto/efeitos da radiação , Criopreservação/instrumentação , Crioprotetores/administração & dosagem , Lasers , Criopreservação/métodos , Dimetil Sulfóxido/administração & dosagem , Etilenoglicol/administração & dosagem , Humanos
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