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1.
Cryobiology ; 103: 39-44, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34606824

RESUMEN

Data about cryoprotectant-free cryopreservation of human ICSI spermatozoa are limited. The aim of this investigation was to compare two technologies for cryopreservation of spermatozoa from men with oligoasthenoteratozoospermia: standard conventional freezing with 5% glycerol (freezing in glycerol) and cryoprotectant-free freezing with 5% high-molecular-weight (360 kDa) polyvinylpyrrolidone (PVP) (PVP-freezing). Capillaries with spermatozoa were cooled in vapor and then plunginged into liquid nitrogen. Head-, midpiece- and tail-abnormality of spermatozoa, mitochondrial membrane potential (MMP) and DNA fragmentation rates after cryopreservation were evaluated. After warming of spermatozoa, fertilization of oocytes (ICSI) was performed. It was detected the lower rate of morphological abnormalities of PVP-frozen spermatozoa in comparison with cells frozen with glycerol (34.6 ± 4.1% vs. 20.7 ± 4.7%, respectively) (P < 0.05). Quality of cells with high MMP after warming in spermatozoa frozen with glycerol was lower than in PVP-frozen spermatozoa (34.7 ± 4.2 vs. 54.5 ± 4.2%, respectively) (P < 0.05). It was established that the DNA fragmentation rate in PVP-frozen spermatozoa was significantly lower in comparison with spermatozoa frozen with glycerol (23.1 ± 2.5% vs. 38.8 ± 3.0%, respectively) (P < 0.05). After fertilization (ICSI) of oocytes, it was established that cleavage and blastulation rates were higher in oocytes after fertilization with PVP-frozen spermatozoa than with spermatozoa frozen with glycerol. Fertilization-, development to 8-blastomeres-, and blastocyst-rates were for PVP-frozen and spermatozoa frozen with glycerol, respectively: 94.4 ± 7.8 vs. 82.2 ± 6.2% (P > 0.1 with tendency to increasing), 90.0 ± 4.6 vs. 69.5 ± 5.1% (P < 0.05), and 45.4 ± 4.1% vs. 30.9 ± 3.3% (P < 0.05). It was concluded that permeable cryoprotectant-free freezing with 5% high-molecular-weight (360 kDa) polyvinylpyrrolidone can be applied successfully for cryopreservation of human oligoasthenoteratozoospremic spermatozoa.


Asunto(s)
Polímeros , Preservación de Semen , Criopreservación/métodos , Crioprotectores , Congelación , Humanos , Masculino , Motilidad Espermática , Espermatozoides
2.
Bull Environ Contam Toxicol ; 106(5): 812-818, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33821297

RESUMEN

The aim of this work is to study precipitation chemistry in the cross-border region between Turkey and Bulgaria, situated on the south-eastern part of the Balkan Peninsula. A total of 115 wet deposition samples were collected and analysed for pH values and major ions (Na+, Mg2+, Ca2+, K+, NH4+, Cl-, NO3-, and SO42-) throughout the summer and autumn seasons of 2014. The enrichment factor analysis and non-sea salt estimates were conducted to determine the possible sources of ions in the wet deposition for the sampling period. The trajectories of the cyclones affecting the area during the study period were also analysed by separating them in different groups. The minimum, average and maximum pH values for the first group of cyclones (CG1) are 4.30, 6.04, 7.40, and 4.00, 6.14, 7.43 for the second group cyclones (CG2), respectively. The non-sea salt fractions of the K+ ion were found to be 0.94 in CG1 and 0.90 in CG2. Also, the Mg2+ ion in CG1 and CG2 is 44% and 60% of the sea salt source.


Asunto(s)
Contaminantes Atmosféricos , Tormentas Ciclónicas , Contaminantes Atmosféricos/análisis , Bulgaria , Monitoreo del Ambiente , Estaciones del Año , Turquía
3.
Life (Basel) ; 14(7)2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-39063584

RESUMEN

With the improvement of medical devices for diagnosis and radiotherapy, concerns about the effects of low doses of ionizing radiation are also growing. There is no consensus among scientists on whether they might have beneficial effects on humans in certain cases or pose more risks, making the exposure unreasonable. While the damaging consequences of high-dose radiation have been known since the discovery of radioactivity, low-dose effects present a much bigger investigative challenge. They are highly specific and include radio-adaptive responses, bystander effects, and genomic instability. Current data regarding the consequences of exposure to low-dose radiation on the quality of male gametes and fertility potential are contradictory. The reports suggest two directions: indirect impact on male gametes-through spermatogenesis-or direct effects at low doses on already mature spermatozoa. Although mature gametes are used for observation in both models, they are fundamentally different, leading to varied results. Due to their unique physiological characteristics, in certain cases, exposure of spermatozoa to low-dose ionizing radiation could have positive effects. Despite the findings indicating no beneficial effects of low-dose exposure on male fertility, it is essential to research its impact on mature spermatozoa, as well.

4.
F S Rep ; 5(2): 145-151, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38983741

RESUMEN

Objective: To study the possibility of increasing the cooling rates of the vitrification procedure in a closed system with the use of aluminum oxide as an intermediate coolant. Design: Case report. Subjects: Six patients undergoing procedures for assisted reproduction. Intervention: Comparative studies of cryopreservation of donor embryos with aluminum oxide as an intermediate cooling agent (experimental group) and without it (control group) have been performed. After thawing, the embryo morphology and its potential to develop to the blastocyst stage have been assessed. The methodology was then applied to clinical practice. Main Outcome Measures: Twenty embryos of 6 patients have been vitrified on day 4 after fertilization with the use of aluminum oxide as an intermediate coolant. Fourteen of them have been thawed. All have displayed normal morphology and 10 have formed blastocysts after 24 hours of culture. Four of the patients received embryo transfer with 2 embryos and the other 2 with single embryos. Results: After preliminary comparative studies of embryos frozen with aluminum oxide and a control group, the results showed no statistically significant difference between their quality and potential to reach to blastocyst stage. That gave us ground to apply the methodology in clinical practice. After the embryo transfer, 3 clinical pregnancies with successful live births have been obtained. Conclusions: Our experience shows that preimplantation embryos can be cryopreserved aseptically, in closed systems, with the help of aluminum oxide as an intermediate coolant.

5.
Cell Biol Int ; 34(5): 455-62, 2010 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-20064109

RESUMEN

Fetal stem cells possess some intriguing characteristics, which delineate them as promising cellular therapeutics. They are less immunogenic, at lower stage of differentiation and have higher potential for repopulation and migration. Furthermore, the fetal stem cells secrete a set of cytokines and growth factors, which stimulate the regeneration of the recipient tissue. The present study indicated that the adhesive fraction of human fetal liver cells possessed the morphological characteristics of mesenchymal stem cells, as well as potential to differentiate into adipocyte and osteoblast lineages. The immunophenotypic analysis showed that the cells expressed CD13, CD73, CD90 and CD105 (typical for mesenchymal stem cells) and lacked the haematopoietic lineage markers CD34 and CD45. Addressing the issue of the low-temperature storage of the human fetal liver cells, four different methods for cryopreservation were assessed: conventional slow freezing, program freezing and two vitrification protocols. The obtained results demonstrated that the cells were cryotolerant and maintained their properties and differentiation potential after thawing. Program freezing showed to be the most efficient method for cryopreservation of the investigated cells.


Asunto(s)
Criopreservación/métodos , Células Madre Fetales/citología , Hígado/citología , Hígado/embriología , Células Madre Mesenquimatosas/citología , Adipogénesis , Biomarcadores/metabolismo , Diferenciación Celular , Linaje de la Célula , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Células Madre Fetales/fisiología , Humanos , Inmunofenotipificación , Células Madre Mesenquimatosas/fisiología , Osteogénesis
6.
Ann Diagn Pathol ; 7(3): 160-4, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12808567

RESUMEN

We report the case of a 65-year-old woman who presented with persistent dry cough and was initially treated for pneumonia without much improvement. Computed tomography of the chest showed a 2.5 cm poorly marginated right infrahilar opacity and multiple ill-defined ground glass opacities scattered throughout the lungs. Computed tomography-guided fine needle aspiration of the right infrahilarmass showed malignant epithelioid cells, many of which were strikingly plasmacytoid with a vacuolated cytoplasm suggesting signet ring cells. A diagnosis of adenocarcinoma with signet ring cell features was made and, in view of the clinical history of multiple masses in the lung, metastatic adenocarcinoma from sites such as gastrointestinal or pancreaticobiliary tract was favored. The patient underwent exploratory thoracotomy during which she was found to have multiple, small pulmonary nodules, one of which was sampled for intraoperative examination. Frozen section of the nodule was interpreted as adenocarcinoma with signet ring cell features, probably metastatic in origin. Histopathologic examination of the pulmonary nodules demonstrated fairly well-delineated lesions with an acellular central zone of hyalinized matrix surrounded by a more cellular zone of moderately pleomorphic epithelioid cells, some of which had a peripherally displaced nucleus and vacuolated cytoplasm resembling signet ring cells. The epithelioid cells were positive for vascular markers CD31 and CD34 and, therefore, a diagnosis of epithelioid hemangioendothelioma was confirmed. This case clearly indicates the importance of recognizing the cytomorphologic and histologic spectrum of this entity to avoid misdiagnosing it as either primary or metastatic adenocarcinoma.


Asunto(s)
Carcinoma de Células en Anillo de Sello/secundario , Errores Diagnósticos/prevención & control , Hemangioendotelioma Epitelioide/patología , Neoplasias Pulmonares/patología , Anciano , Biomarcadores de Tumor , Diagnóstico Diferencial , Femenino , Hemangioendotelioma Epitelioide/química , Humanos , Inmunohistoquímica , Neoplasias Pulmonares/química
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