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1.
Cryobiology ; 114: 104845, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38184269

RESUMO

Intracellular calcium homeostasis plays a crucial role in spermatozoa by regulating physiological functions associated with sperm quality and male fertility potential. Intracellular calcium fine balance in the sperm cytoplasm is strictly dependent on sperm surface channels including the CatSper channel. CatSpers' role is to ensure the influx of extracellular calcium, while intracellular pH alkalinization serves as a stimulus for the activation of several channels, including CatSper. Overall, the generation of intracellular calcium spikes through CatSper is essential for fertilization-related processes, such as sperm hyperactivation, acrosome reaction, egg chemotaxis, and zona pellucida penetration. Multiple lines of evidence suggest that disruption in the close interaction among ions, pH, and CatSper could impair male fertility potential. In contemporary times, the growing reliance on Medically Assisted Reproduction procedures underscores the impact of cryopreservation on gametes. In fact, a large body of literature raises concerns about the cryo-damages provoked by the freeze-thawing processes, that can affect the plasma membrane integrity, thus the structure of pivotal ion channels, and the fine regulation of both intracellular calcium and pH. This review aims to provide an overview of the importance of the CatSper channel in sperm quality and further fertilization potential. Additionally, it addresses the emerging issue of cryopreservation's impact on the functionality of this sperm channel.


Assuntos
Canais de Cálcio , Sinalização do Cálcio , Masculino , Humanos , Canais de Cálcio/metabolismo , Sêmen/metabolismo , Cálcio/metabolismo , Criopreservação/métodos , Espermatozoides/fisiologia , Íons/metabolismo , Membrana Celular/metabolismo , Fertilidade , Motilidade dos Espermatozoides
2.
Cells ; 12(12)2023 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-37371043

RESUMO

Liquid biopsies refer to the isolation and analysis of tumor-derived biological material from body fluids, most commonly blood, in order to provide clinically valuable information for the management of cancer patients. Their non-invasive nature allows to overcome the limitations of tissue biopsy and complement the latter in guiding therapeutic decision-making. In the past years, several studies have demonstrated that circulating tumor DNA (ctDNA) detection can be used in the clinical setting to improve patient prognosis and monitor therapy response, especially in metastatic cancers. With the advent of significant technological advances in assay development, ctDNA can now be accurately and reliably identified in early-stage cancers despite its low levels in the bloodstream. In this review, we discuss the most important studies that highlight the potential clinical utility of ctDNA in early-stage breast cancer focusing on early diagnosis, detection of minimal residual disease and prediction of metastatic relapse. We also offer a concise description of the most sensitive techniques that are deemed appropriate for ctDNA detection in early-stage cancer and we examine their advantages and disadvantages, as they have been employed in various studies. Finally, we discuss future perspectives on how ctDNA could be better integrated into the everyday oncology practice.


Assuntos
Neoplasias da Mama , DNA Tumoral Circulante , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , DNA Tumoral Circulante/genética , Biomarcadores Tumorais , Recidiva Local de Neoplasia , Biópsia Líquida/métodos
3.
Int J Mol Sci ; 24(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37298244

RESUMO

Controlled ovarian stimulation (COS) through gonadotropin administration has become a common procedure in assisted reproductive technologies. COS's drawback is the formation of an unbalanced hormonal and molecular environment that could alter several cellular mechanisms. On this basis, we detected the presence of mitochondrial DNA (mtDNA) fragmentation, antioxidant enzymes (catalase; superoxide dismutases 1 and 2, SOD-1 and -2; glutathione peroxidase 1, GPx1) and apoptotic (Bcl-2-associated X protein, Bax; cleaved caspases 3 and 7; phosphorylated (p)-heat shock protein 27, p-HSP27) and cell-cycle-related proteins (p-p38 mitogen-activated protein kinase, p-p38 MAPK; p-MAPK activated protein kinase 2, p-MAPKAPK2; p-stress-activated protein kinase/Jun amino-terminal kinase, p-SAPK/JNK; p-c-Jun) in the oviducts of unstimulated (Ctr) and repeatedly hyperstimulated (eight rounds, 8R) mice. While all the antioxidant enzymes were overexpressed after 8R of stimulation, mtDNA fragmentation decreased in the 8R group, denoting a present yet controlled imbalance in the antioxidant machinery. Apoptotic proteins were not overexpressed, except for a sharp increase in the inflammatory-related cleaved caspase 7, accompanied by a significant decrease in p-HSP27 content. On the other hand, the number of proteins involved in pro-survival mechanisms, such as p-p38 MAPK, p-SAPK/JNK and p-c-Jun, increased almost 50% in the 8R group. Altogether, the present results demonstrate that repeated stimulations cause the activation of the antioxidant machinery in mouse oviducts; however, this is not sufficient to induce apoptosis, and is efficiently counterbalanced by activation of pro-survival proteins.


Assuntos
Antioxidantes , Proteínas Quinases Ativadas por Mitógeno , Camundongos , Animais , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno , Proteínas de Choque Térmico HSP27 , Proteínas Quinases p38 Ativadas por Mitógeno , Apoptose , Proteína Quinase 8 Ativada por Mitógeno , DNA Mitocondrial
4.
Front Vet Sci ; 10: 1151254, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143497

RESUMO

The broad conceptualization of fertility preservation and restoration has become already a major concern in the modern western world since a large number of individuals often face it in the everyday life. Driven by different health conditions and/or social reasons, a variety of patients currently rely on routinely and non-routinely applied assisted reproductive technologies, and mostly on the possibility to cryopreserve gametes and/or gonadal tissues for expanding their reproductive lifespan. This review embraces the data present in human-focused literature regarding the up-to-date methodologies and tools contemporarily applied in IVF laboratories' clinical setting of the oocyte, sperm, and embryo cryopreservation and explores the latest news and issues related to the optimization of methods used in ovarian and testicular tissue cryopreservation.

5.
Cells ; 11(10)2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35626673

RESUMO

After its discovery in 1825 by the physiologist J.E. Purkinje, the human germinal vesicle (GV) attracted the interest of scientists. Discarded after laparotomy or laparoscopic ovum pick up from the pool of retrieved mature oocytes, the leftover GV was mainly used for research purposes. After the discovery of Assisted Reproductive Technologies (ARTs) such as in vitro maturation (IVM), in vitro fertilization and embryo transfer (IVF-ET) and intracytoplasmic sperm injection (ICSI), its developing potential was explored, and recognized as an important source of germ cells, especially in the case of scarce availability of mature oocytes for pathological/clinical conditions or in the case of previous recurrent implantation failure. We here review the ultrastructural data available on GV-stage human oocytes and their application to ARTs.


Assuntos
Oócitos , Injeções de Esperma Intracitoplásmicas , Núcleo Celular , Fertilização In Vitro , Humanos
6.
J Assist Reprod Genet ; 39(4): 905-918, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35312936

RESUMO

In mammalian species an optimal fertilization window during which successful fertilization occurs. In the majority of mammals estrus marks ovulation time and coincident with mating, thereby allowing the synchronized meeting in the fallopian tubes, between freshly ejaculated sperm and freshly ovulated oocytes. Conversely, women do not show natural visual signs of ovulation such that fertilization can occur hours later involving an aged oocyte and freshly ejaculated spermatozoa. During this time, the oocyte undergoes a rapid degradation known as "postovulatory aging" (POA). POA may become particularly important in the human-assisted reproductive technologies, as the fertilization of retrieved mature oocytes can be delayed due to increased laboratory workload or because of unforeseeable circumstances, like the delayed availability of semen samples. This paper is an updated review of the consequences of POA, either in vivo or in vitro, on oocyte quality with particular attention to modifications caused by POA on oocyte nuclear, cytoplasmic, genomic, and epigenetic maturation, and embryo development.


Assuntos
Senescência Celular , Oócitos , Idoso , Envelhecimento/genética , Animais , Desenvolvimento Embrionário , Feminino , Humanos , Masculino , Mamíferos , Ovulação
7.
Can J Dent Hyg ; 54(1): 26-31, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33240361

RESUMO

Background: The use of medicated mouthwashes and gels in the home care maintenance of dental implants is controversial due to the possibility of residue deposition on the implant collar. The aim of this in vitro study was to analyse, by means of scanning electron microscopy (SEM), the amount of residues on dental implant collars treated with various commercial home dental care products. Methods: Gel and mouthwash products were tested on 10 implants. The gels included sodium fluoride, amine fluoride, and sodium hyaluronate products. The mouthwashes tested contained triclosan, nimesulide, stannous fluoride, amine fluoride, and hexetidine-chlorobutanol. The SEM observations were performed at different magnifications in double modality SE (secondary electrons) and BSE (backscattered electrons) to qualitatively assess any residual products. The image quantitative analysis was performed by Image J® software to assess areas occupied by residuals. All results were analysed by the same researcher with experience in electron microscopy. Results: The fluoride-based gel products left wider areas occupied by residuals than the mouthwash products. In particular the fluoride-based and hyaluronate products left the highest amount of residues. Among mouthwashes, fluoride-based and triclosan products showed the highest amount of residuals deposition. Discussion: Oral hygiene procedures and related professional products are fundamental to the prevention, treatment, and control of microorganisms. In the case of implants, mechanical and chemical plaque control strategies are even more important since the potentially harmful biofilm covers abiotic titanium surfaces. In situ fixture maintenance is crucial for dental implant therapy success. Correct recommendation of home care products for bacterial control is fundamental to the health of implants and their surrounding tissues. Conclusions: Data from this experimental study showed that home care commercial products in gel formulation, especially those containing fluoride, leave more residuals on titanium smooth surfaces than mouthwash products. The longer permanence of the products may lead to a more effective plaque control than other products.


Contexte: L'utilisation de bains de bouche et de gels médicamentés lors des soins d'entretien à domicile des implants dentaires porte à controverse en raison de la possibilité de dépôts de résidus sur le collet de l'implant. La présente étude in vitro visait à analyser par microscopie électronique à balayage (MÉB) la quantité de résidus sur les collets d'implants dentaires traités in vitro avec divers produits commerciaux de soins dentaires à domicile. Méthodologie: Les produits de gels et de bains de bouche ont été testés sur 10 implants. Les gels comprenaient les produits de fluorure de sodium, de fluorure d'amine et de hyaluronate de sodium. Les bains de bouche évalués contenaient du triclosan, de la nimésulide, du fluorure d'étain et du hexétidine-chlorobutanol. Les observations par MÉB ont été effectuées à diverses amplifications en modalité double SE (électrons secondaires) et BSE (électrons rétrodiffusés) pour évaluer de manière qualitative tout produit résiduel. L'analyse quantitative de l'image a été effectuée à l'aide du logiciel Image J® pour évaluer les zones ayant des résidus. Tous les résultats ont été analysés par le même chercheur expérimenté dans le domaine de la microscopie électronique. Résultats: Les produits de gels à base de fluorure ont laissé des résidus sur de plus vastes zones que les produits de bains de bouche. En particulier, les produits à base de fluorure et le hyaluronate ont laissé la plus grande quantité de résidus. Parmi les bains de bouche, les produits à base de fluorure et de triclosan ont révélé la plus grande quantité de dépôts de résidus. Discussion: Les procédures d'hygiène buccodentaire et les produits professionnels qui y sont liés sont essentiels à la prévention, au traitement et au contrôle des microorganismes. En matière d'implants, les stratégies de contrôle mécanique et chimique de la plaque sont encore plus importantes puisque le biofilm potentiellement nocif couvre les surfaces abiotiques du titane. L'entretien in situ du montage est primordial au succès de la thérapie de l'implant dentaire. La bonne recommandation de produits de soins à domicile pour le contrôle des bactéries est essentielle à la santé des implants et des tissus environnants. Conclusions: Les données de cette étude expérimentale ont montré que les produits commerciaux de soins à domicile en formule de gels, surtout ceux contenant du fluorure, laissent une plus grande quantité de résidus sur les surfaces lisses du titane que les produits de bains de bouche. La permanence plus longue des produits peut mener à un contrôle plus efficace de la plaque que d'autres produits.


Assuntos
Implantes Dentários , Placa Dentária , Humanos , Microscopia Eletrônica de Varredura , Antissépticos Bucais , Higiene Bucal
8.
Syst Biol Reprod Med ; 66(4): 229-235, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32379506

RESUMO

Over the last forty years, many trials have been performed using mammalian embryo cultures with reduced oxygen tension (O2) to encourage proper embryo development and increase the success rate for in vitro fertilization (IVF) outcome. Even if the use of atmospheric O2 (20%) affects in vitro embryo development and intracellular redox balance, the use of low (5% O2, physiologic) and ultra-low (close or less to 5% O2) O2 applied to in vitro embryo culture is still under debate. Numerous studies in various mammalian species have shown that embryo development improves when culturing embryos under low O2, although culture conditions are not the only factors involved in the success of IVF. This article reviews the literature data of the last four decades and discusses the current evidence on the use of low and ultra-low O2 in embryo culture, and examines the impact of multiple factors on IVF outcomes. ABBREVIATIONS: O2: oxygen tension; IVF: in vitro fertilization; IVC: in vitro culture; ET: embryo transfer; ROS: reactive oxygen species; ARTs: assisted reproductive technologies.


Assuntos
Técnicas de Cultura Embrionária , Embrião de Mamíferos/metabolismo , Fertilização In Vitro , Oxigênio/metabolismo , Desenvolvimento Embrionário , Feminino , Humanos , Gravidez , Resultado da Gravidez
9.
Artigo em Inglês | MEDLINE | ID: mdl-32413976

RESUMO

Assisted Reproductive Technologies routinely utilize different culture media and oxygen (O2) concentrations to culture human embryos. Overall, embryos cultured under physiological O2 tension (5%) have improved development compared to embryos cultured under atmospheric O2 conditions (20%). The mechanisms responsible for this remain unclear. This study aimed to evaluate the effect of physiologic (5%) or atmospheric O2 (20%) tension on the microscopic ultrastructure of pre-implantation mouse embryos using Transmission Electron Microscopy (TEM). Embryos flushed out of the uterus after natural mating were used as the control. For use as the control, 2-cells, 4-cells, morulae, and blastocysts were flushed out of the uterus after natural fertilization. In vitro fertilization (IVF) was performed using potassium simplex optimized medium (KSOM) under different O2 tensions (5% and 20%) until the blastocyst stage. After collection, embryos were subjected to the standard preparative for light microscopy (LM) and TEM. We found that culture in vitro under 5% and 20% O2 results in an increase of vacuolated shaped mitochondria, cytoplasmic vacuolization and presence of multi-vesicular bodies at every embryonic stage. In addition, blastocysts generated by IVF under 5% and 20% O2 showed a lower content of heterochromatin, an interruption of the trophectodermal and inner cell mass cell membranes, an increased density of residual bodies, and high levels of glycogen granules in the cytoplasm. In conclusion, this study suggests that in vitro culture, particularly under atmospheric O2 tension, causes stage-specific changes in preimplantation embryo ultrastructure. In addition, atmospheric (20%) O2 is associated with increased alterations in embryonic ultrastructure; these changes may explain the reduced embryonic development of embryos cultured with 20% O2.


Assuntos
Blastocisto , Desenvolvimento Embrionário , Oxigênio , Animais , Meios de Cultura , Embrião de Mamíferos , Feminino , Fertilização In Vitro , Camundongos , Gravidez
10.
J Reprod Dev ; 66(4): 387-397, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32350229

RESUMO

Controlled ovarian hyperstimulation (COH) is routinary used in assisted reproductive technologies (ARTs) to increase the yields of mature oocytes. The possibility that patients with a history of failures or poor-responders may develop side-effects following these treatments is still debated. Epidemiological studies reported controversial results about pregnancy outcome and the risk of developing gynecological cancers. By using a mouse model, here we compared the ultrastructural features of fallopian tubes (FTs) obtained from mice undergoing or not (control, CTR) four (4R) and eight (8R) rounds of gonadotropin stimulation. Although the morphological characteristics of oviductal layers seemed unaffected by repeated treatments, dose-response ultrastructural alterations in the ampulla appeared in the 4R group and even more in the 8R group. The targets were oviductal ciliated (CCs) and non-ciliated (NCCs) cells, which showed damaged mitochondria and glycogen accumulations in the cytoplasm. The drastic reduction of CCs, evident after 4R, was supported by the absence of cilia. After 8R, glycogen granules were significantly reduced and massive degeneration of mitochondria, which appeared swollen and/or vacuolated, occurred in NCCs. Moreover, disintegrated mitochondria were found at the periphery of mitophagic vacuoles with evident signs of cristolysis. The morphometric analysis evidenced a significant increase in the density and frequency of damaged mitochondria after 4R and 8R. The absence of cilia, necessary to sustain oviductal transport of oocytes, spermatozoa and embryos, may originate from either mitochondrial dysfunction or glycogen consumption. These results suggest that repeated COH treatments could induce alterations impairing fertilization and embryo transport toward the uterus.


Assuntos
Cílios/ultraestrutura , Epitélio/ultraestrutura , Tubas Uterinas/ultraestrutura , Indução da Ovulação , Animais , Feminino , Camundongos , Mitocôndrias/ultraestrutura , Mitofagia/fisiologia , Vacúolos/ultraestrutura
11.
Int. j. morphol ; 38(1): 96-100, Feb. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1056404

RESUMO

During aging, usually graying of the hair occurs as a result of oxidative stress. Driven by social acceptance and self-perception of the exterior appearance, both men and women rely on hair dyeing products, in order to mask the graying hair. At the same time, a frequent use of synthetic products and treatment can damage the hair shaft; for this reason, this study aimed to evaluate the morphological effect of the herbal dye derived from Lawsonia inermis (henna), on hair. Dyed hairs were evaluated by means of SEM. Subsequently, they were compared, qualitatively and quantitatively, with undyed hairs. Results showed a positive impact on the cuticula pattern and on the diameters of the examined samples, after henna application. Different results, about the degree and the type of morphological changes occurring on pigmented hairs, may depend on the phenotype and on the health condition of hair, before dye treatment.


Durante el envejecimiento, generalmente se produce el envejecimiento del cabello como resultado del estrés oxidativo. Motivados por la aceptación social y la autopercepción de la apariencia, tanto hombres como mujeres confían en productos para teñir el cabello para enmascarar las canas. Al mismo tiempo, el uso frecuente de productos y tratamientos sintéticos puede dañar el tallo del cabello. Por esta razón, este estudio tuvo como objetivo evaluar el efecto morfológico del tinte derivado de Lawsonia inermis (henna) en el cabello. Los cabellos teñidos se evaluaron mediante SEM. Posteriormente, se compararon, cualitativa y cuantitativamente, con cabellos sin teñir. Los resultados mostraron un impacto positivo en el patrón de la cutícula y en los diámetros de las muestras examinadas, después de la aplicación de henna. Los diferentes resultados, sobre el grado y el tipo de cambios morfológicos que ocurren en los cabellos pigmentados, pueden depender del fenotipo y del estado de salud del cabello, antes del tratamiento con tinte.


Assuntos
Humanos , Microscopia Eletrônica de Varredura , Folículo Piloso/efeitos dos fármacos , Lawsonia (Planta) , Tinturas para Cabelo/farmacologia , Folículo Piloso/ultraestrutura , Cabelo/efeitos dos fármacos , Cabelo/ultraestrutura
12.
Arch Gynecol Obstet ; 300(1): 207-215, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30941554

RESUMO

PURPOSE: The aim of this study is to evaluate the sperm DNA fragmentation index (DFI) in oocyte donation cycles and correlate it with the sperm parameters, the male characteristics, the embryo quality and the outcome of intracytoplasmic sperm injection (ICSI). METHODS: A total of 150 couples participating in an oocyte donation program were included in the study. Sperm samples were assessed by conventional sperm analysis. DFI was evaluated using the Halosperm kit, a sperm chromatin dispersion test (SCD). RESULTS: The relations between DNA damage and epidemiological male factors (age, height, weight), standard semen parameters (concentration, total and forward motility, and morphology), and embryological and clinical parameters (fertilization rate, total blastocyst number, number of good quality blastocyst, clinical pregnancy) were analyzed. DFI was positively correlated with advanced male age (r = 0.23, p < 0.05) and negatively correlated with total sperm and forward motility (r = - 0.29, r = - 0.27, respectively; p < 0.05). DFI was not significantly correlated with pregnancy outcome in oocyte donation cycles (r = - 0.05, p > 0.05). When good quality blastocysts were chosen, a trend toward the development of good quality embryos was detected in the presence of a low DFI (r = - 0.20, p = 0.08). CONCLUSIONS: DFI does not significantly affect the outcome of ICSI in oocyte donation cycles. Even in cases of advanced paternal age that a high DFI resulted sperm DNA fragmentation seems not to adversely affect the final outcome.


Assuntos
Fragmentação do DNA , Doação de Oócitos/métodos , Oócitos/metabolismo , Injeções de Esperma Intracitoplásmicas/métodos , Espermatozoides/metabolismo , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Estudos Prospectivos
13.
J Reprod Dev ; 64(1): 75-82, 2018 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-29225323

RESUMO

Mancozeb, an ethylene bis-dithiocarbamate, is widely used as a fungicide and exerts reproductive toxicity in vivo and in vitro in mouse oocytes by altering spindle morphology and impairing the ability to fertilize. Mancozeb also induces a premalignant status in mouse granulosa cells (GCs) cultured in vitro, as indicated by decreased p53 expression and tenuous oxidative stress. However, the presence and extent of ultrastructural alterations induced by mancozeb on GCs in vitro have not yet been reported. Using an in vitro model of reproductive toxicity, comprising parietal GCs from mouse antral follicles cultured with increasing concentrations of mancozeb (0.001-1 µg/ml), we sought to ascertain the in vitro ultrastructural cell toxicity by means of transmission (TEM) and scanning (SEM) electron microscopy. The results showed a dose-dependent toxicity of mancozeb on mouse GCs. Ultrastructural data showed intercellular contact alterations, nuclear membrane irregularities, and chromatin marginalization at lower concentrations, and showed chromatin condensation, membrane blebbing, and cytoplasmic vacuolization at higher concentrations. Morphometric analysis evidenced a reduction of mitochondrial length in GCs exposed to mancozeb 0.01-1 µg/ml and a dose-dependent increase of vacuole dimension. In conclusion, mancozeb induced dose-dependent toxicity against GCs in vitro, including ultrastructural signs of cell degeneration compatible with apoptosis, likely due to the toxic breakdown product ethylenethiourea. These alterations may represent a major cause of reduced/delayed/missed oocyte maturation in cases of infertility associated with exposure to pesticides.


Assuntos
Fungicidas Industriais/farmacologia , Células da Granulosa/efeitos dos fármacos , Maneb/farmacologia , Zineb/farmacologia , Animais , Apoptose/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Células da Granulosa/metabolismo , Células da Granulosa/ultraestrutura , Camundongos , Estresse Oxidativo/efeitos dos fármacos
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