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1.
Adv Rheumatol ; 61: 9, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1152744

RESUMO

Abstract Background: In the past 20 years, hematopoietic stem cell transplantation (HSCT) has been investigated as treatment for systemic sclerosis (SSc). The goal of HSCT is to eradicate the autoreactive immune system, which is replaced by a new immune repertoire with long-lasting regulation and tolerance to autoantigens. Here, we describe the clinical outcomes of severe and refractory SSc patients that underwent HSCT at a single Brazilian center. Patients and methods: This is a longitudinal and retrospective study, including 70 adult SSc patients, with an established diagnosis of SSc, and who underwent autologous HSCT from 2009 to 2016. The procedure included harvesting and cryopreservation of autologous hematopoietic progenitor cells, followed by administration of an immunoablative regimen and subsequent infusion of the previously collected cells. Patients were evaluated immediately before transplantation, at 6 months and then yearly until at least 5-years of post-transplantation follow-up. At each evaluation time point, patients underwent clinical examination, including modified Rodnan's skin score (mRSS) assessment, echocardiography, high-resolution computed tomography of the lungs and pulmonary function. Results: Median (range) age was 35.9 (19-59), with 57 (81.4%) female and median (range) non-Raynaud's disease duration of 2 (1-7) years. Before transplantation, 96% of the patients had diffuse skin involvement, 84.2%, interstitial lung disease and 67%, positive anti-topoisomerase I antibodies. Skin involvement significantly improved, with a decline in mRSS at all post-transplantation time points until at least 5-years of follow-up. When patients with pre-HSCT interstitial lung disease were analyzed, there was an improvement in pulmonary function (forced vital capacity and diffusing capacity of lung for carbon monoxide) over the 5-year follow-up. Overall survival was 81% and progression-free survival was 70.5% at 8-years after HSCT. Three patients died due to transplant-related toxicity, 9 patients died over follow-up due to disease reactivation and one patient died due to thrombotic thrombocytopenic purpura. Conclusions: Autologous hematopoietic progenitor cell transplantation improves skin and interstitial lung involvement. These results are in line with the international experience and support HSCT as a viable therapeutic alternative for patients with severe and progressive systemic sclerosis.(AU)


Assuntos
Humanos , Adulto , Escleroderma Sistêmico/cirurgia , Células-Tronco Hematopoéticas , Criopreservação/instrumentação , Transplante de Células-Tronco Hematopoéticas/instrumentação , Progressão da Doença , Estudos Retrospectivos , Estudos Longitudinais
2.
Ciênc. Anim. (Impr.) ; 31(3): 38-52, 2021. graf
Artigo em Português | VETINDEX | ID: biblio-1369025

RESUMO

Devido à alta sensibilidade do espermatozoide suíno à criopreservação, torna-se importante o estudo acerca dos danos provocados à célula, pela agressão térmica ocasionada durante este processo. Sendo assim, avaliou-se neste trabalho, a influência de diferentes embalagens, utilizadas para o armazenamento de sêmen suíno, sobre a qualidade do espermatozoide criopreservado. Foram utilizados animais híbridos, a coleta do sêmen foi feita pela técnica da mão enluvada. Foram analisados o vigor (0 a 5), a motilidade (0 a 100%), a taxa de degradação da motilidade e a integridade acrossomal. O sêmen foi congelado em palhetas de 0,5mL, criotubos de 2,0mL e macrotubos de 4 e 5mL. As amostras de sêmen suíno congelado em palhetas apresentaram os melhores resultados de vigor espermático (2,3), de motilidade (45,4%), de taxa de degradação da motilidade (56,5%) e de integridade acrossomal (60,6%), quando comparadas às amostras criopreservadas nos demais tipos de embalagens avaliadas (p<0,05). Somente para o parâmetro taxa de degradação da motilidade, o sêmen conservado em palhetas apresentou resultados similares ao conservado em macrotubo de 4mL (54,1%). Os resultados pós-descongelação indicaram que o sêmen envasado nas palhetas foi o que apresentou características condizentes com a possibilidade de serem utilizados nos protocolos de inseminação artificial, com possibilidades de bons resultados de fertilidade. Concluiu-se que embalagens que permitam uma maior velocidade de trocas de temperatura entre as células encontradas no bordo e no centro, favorecem a uma melhor qualidade do sêmen descongelado.


Due to high sensitivity of the swine spermatozoa to cryopreservation, it is important to study the damage caused to the cell by thermal aggression during this process. Thus, this study evaluated the influence of different packages used for the storage of swine semen on the quality of cryopreserved spermatozoa. Hybrid animals were used, and semen collection was made by the gloved hand technique. The vigor (0 the 5), motility (0 the 100%), rate of motility degradation and acrosome integrity were analyzed. The semen was frozen in straws of 0.5mL, cryotubes of 2.0mL and macrotubes of 4 and 5mL. The swine semen samples frozen in straws showed the best results in sperm vigor (2.3), motility (45.4%), motility degradation rate (56.5%) and acrosomal integrity (60.6%), when compared to the cryopreserved samples in the other types of packaging evaluated (p<0.05). Only for the motility degradation rate parameter, the semen preserved in straws showed results similar to the one conserved in a 4 mL macrotube (54.1%). The results after thawing indicated that the semen packed in straws was the one that presented consistent characteristics with the possibility of being used in artificial insemination protocols with possibilities of good fertility results. It was concluded that packages that allow a higher speed of temperature changes between the cells found on the edge and in the center of them, favor a better quality of the thawed semen.


Assuntos
Animais , Masculino , Preservação do Sêmen/instrumentação , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Suínos , Embalagem de Produtos , Temperatura Alta , Criopreservação/instrumentação , Criopreservação/veterinária
3.
Biopreserv Biobank ; 18(3): 165-170, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32083486

RESUMO

The cryobanks of agouti somatic tissues represent a promising tool for the conservation of this species and of those that are phylogenetically related and endangered. For these purposes, one strategy to guarantee the quality of samples after warming would be to choose the appropriate tissue vitrification technique. Therefore, we evaluated the effects of two different techniques, direct vitrification in cryovials (DVC) and solid-surface vitrification (SSV), on the preservation of ear somatic tissues derived from agoutis kept in a scientific center of creation. Noncryopreserved somatic tissues were used as controls. Although SSV reduced the thickness of the dermis and cartilage (p < 0.05), the epidermal thickness of these samples was observed to be similar to controls (p > 0.05). Notably, the number of fibroblasts was not altered with either technique. However, both vitrification methods led to an increase in the number of perinuclear halos, with a particularly strong increase observed in DVC-derived fragments (p < 0.05). Compared with the DVC group, SSV showed a larger number of normal chondrocytes and smaller number of degenerate chondrocytes. Furthermore, the number of empty lacunae in SSV-derived fragments remained similar to controls (p > 0.05). In summary, SSV was found to be a more efficient method for vitrifying agouti somatic tissues compared with DVC. These results are important for the proper formation of agouti somatic banks, an essential step in the study of biological resources in this species.


Assuntos
Cartilagem/citologia , Criopreservação/instrumentação , Derme/citologia , Animais , Dasyproctidae , Nanotecnologia , Vitrificação
4.
Rev. biol. trop ; 66(3): 1314-1323, jul.-sep. 2018. tab, graf
Artigo em Inglês | LILACS, SaludCR | ID: biblio-977387

RESUMO

Abstract A cryopreservation protocol was developed for in vitro shoot tips of Garcinia hombroniana using the vitrification technique. Four critical steps in the technique were investigated, namely preculture, loading, dehydration with Plant Vitrification Solution 2 (PVS2), and unloading. Shoot tips precultured for 48 h gave significantly higher survival (75 %) compared to 24 h preculture (50 %) after cryopreservation. Treatment with 1 M glycerol plus 0.4 M sucrose as a loading solution gave higher survival (45.83 %) compared to the other treatments (0.4 M sucrose + 2 M glycerol; 0.4 M sucrose). Shoot tips dehydrated with PVS2 for 25 min gave the highest survival after immersion in liquid nitrogen. Stepwise PVS2 treatment for 15 min with 50 % PVS2 followed by 10 min with 100 % PVS2 solution improved survival of the shoot tips after cryopreservation (41.67 %). Murashige and Skoog medium with 0.4 M sucrose gave significantly higher survival (66.67 %) than MS with 1.2 M sucrose (25 %) as an unloading solution. Water content was shown to decrease throughout the whole vitrification steps from 6.83 ± 1.66 g g-1 dw for fresh shoot tips down to 2.93 ± 0.28 g g-1 dw after PVS2 treatment. Further study on each step including recovery medium is required to improve the survival. Nevertheless, the present study showed the potential of using the vitrification technique for cryopreservation of G. hombroniana. Rev. Biol. Trop. 66(3): 1314-1323. Epub 2018 September 01.


Resumen Se desarrolló un protocolo de crioconservación in vitro para ápices caulinares de Garcinia hombroniana mediante la técnica de vitrificación, con cuatro etapas críticas: precultivo, carga de crioprotector, deshidratación con solución de vitrificación vegetal 2 (PVS2), y descarga. Ápices precultivados por 48 h sobrevivieron más (75 %) que los de 24 h (50 %) después de la crioconservación. El tratamiento con glicerol 1 M más sacarosa 0.4 M como solución de carga permitió mayor sobrevivencia (45.83 %) que los otros tratamientos (sacarosa 0.4 M + glicerol 2 M; sacarosa 0.4 M). Los ápices deshidratados con PVS2 por 25 min registraron la mayor sobrevivencia tras inmersión en nitrógeno líquido. El tratamiento gradual por 15 min con solución de PVS2 al 50 %, seguido por 10 min al 100 %, mejoró la sobrevivencia de ápices tras la crioconservación (41.67 %). El medio Murashige-Skoog (MS) con sacarosa 0.4 M produjo una sobrevivencia significativamente mayor (66.67 %) que MS con sacarosa 1.2 M (25 %) como solución de descarga. El contenido de agua disminuyó a lo largo del proceso de vitrificación desde 6.83 ± 1.66 g g-1 peso seco, en ápices frescos, hasta 2.93 ± 0.28 g g-1 peso seco después del tratamiento con PVS2. Se requiere de más investigación sobre cada etapa, incluyendo el medio de recuperación, para mejorar la tasa de sobrevivencia. Sin embargo, este estudio muestra el potencial de la vitrificación para la crioconservación de G. hombroniana.


Assuntos
Criopreservação/instrumentação , Garcinia , Vitrificação , Plantas , Sacarose/uso terapêutico , Glicerol/uso terapêutico , Malásia , Nitrogênio/uso terapêutico
5.
Biopreserv Biobank ; 15(5): 463-468, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28922611

RESUMO

The brown brocket deer Mazama gouazoubira is 1 of the 10 recognized brocket deer of the Neotropical region. Recently, this species has suffered a population decline due to current threats, mainly poaching and habitat loss. Several studies have shown that some endangered species can benefit from interspecies somatic cell nuclear transfer technology through the use of their somatic cells, such as the fibroblasts. Thus, the aim of this study was to verify the viability and the effect of cryopreservation on fibroblasts after several passages. For this purpose, fibroblast cells were cultured until passages 4, 7, and 10 (cultured control groups) and cryopreserved in cryotubes (frozen/warmed groups). The cellular viability, functionality, and percentage of cells undergoing necrosis and apoptosis were evaluated. The survival rates were always higher than 80% irrespective of the tested group, except for passage 10 in the frozen/warmed group. Population doubling time of cultured cells from passage 10 was significantly higher than that of passages 4 and 7, exhibiting low metabolic activity and a higher percentage of cells in initial apoptosis. In conclusion, the M. gouazoubira fibroblast-derived cell line provides an essential resource for further studies regarding reproductive biotechniques and is likely to be useful as an ex situ conservation strategy.


Assuntos
Criopreservação/métodos , Fibroblastos/citologia , Animais , Apoptose , Sobrevivência Celular , Células Cultivadas , Criopreservação/instrumentação , Cervos
6.
Cryo Letters ; 38(2): 119-124, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28534055

RESUMO

BACKGROUND: Dry ice-ethanol bath (-78 degree C) have been widely used in low temperature biological research to attain rapid cooling of samples below freezing temperature. The prediction of cooling rates of biological samples immersed in dry ice-ethanol bath is of practical interest in cryopreservation. The cooling rate can be obtained using mathematical models representing the heat conduction equation in transient state. Additionally, at the solid cryogenic-fluid interface, the knowledge of the surface heat transfer coefficient (h) is necessary for the convective boundary condition in order to correctly establish the mathematical problem. OBJECTIVE: The study was to apply numerical modeling to obtain the surface heat transfer coefficient of a dry ice-ethanol bath. MATERIALS AND METHODS: A numerical finite element solution of heat conduction equation was used to obtain surface heat transfer coefficients from measured temperatures at the center of polytetrafluoroethylene and polymethylmetacrylate cylinders immersed in a dry ice-ethanol cooling bath. The numerical model considered the temperature dependence of thermophysical properties of plastic materials used. RESULTS: A negative linear relationship is observed between cylinder diameter and heat transfer coefficient in the liquid bath, the calculated h values were 308, 135 and 62.5 W/(m2K) for PMMA 1.3, PTFE 2.59 and 3.14 cm in diameter, respectively. CONCLUSION: The calculated heat transfer coefficients were consistent among several replicates; h in dry ice-ethanol showed an inverse relationship with cylinder diameter.


Assuntos
Criopreservação , Gelo-Seco , Etanol/química , Manejo de Espécimes , Propriedades de Superfície , Condutividade Térmica , Temperatura Baixa , Criopreservação/instrumentação , Criopreservação/métodos , Análise de Elementos Finitos , Modelos Teóricos , Projetos de Pesquisa , Manejo de Espécimes/instrumentação , Manejo de Espécimes/métodos
7.
Andrologia ; 49(7)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27682467

RESUMO

The aims of this study were to evaluate porcine sperm vitrification in cryoloops, with and without two different cryoprotectants and assess two warming procedures. Extended (n = 3; r = 4) and raw (n = 5; r = 2) semen was diluted in media without and with cryoprotectants (4% dimethylformamide and 4% glycerol) to a final concentration of 20 × 106 spermatozoa ml-1 and vitrified using the cryoloops method. Two warming procedures were evaluated: rapid method (30 s at 37°C) and an ultra-rapid method (7 s at 75°C, followed by 30 s at 37°C). Total motility (phase contrast), sperm viability (6-carboxifluorescein diacetate and propidium iodide stain), membrane function (hypo-osmotic swelling test), acrosome integrity (phase contrast), chromatin condensation (toluidine blue stain) and chromatin susceptibility to acid denaturation (acridine orange stain) were evaluated before and after vitrification and analysed using Friedman's test. In all media, the only seminal parameters that were maintained after vitrification were chromatin condensation and integrity. Vitrification of porcine spermatozoon using cryoloops, both in the presence or absence of cryoprotectants and independent of the warming procedure used, permits conservation of sperm chromatin condensation and integrity. It would be interesting to further verify this by producing porcine embryos using vitrified spermatozoon with intracytoplasmic sperm injection.


Assuntos
Criopreservação/veterinária , Preservação do Sêmen/instrumentação , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Sus scrofa , Acrossomo/ultraestrutura , Animais , Cruzamento , Membrana Celular/fisiologia , Sobrevivência Celular , Cromatina/química , Cromatina/fisiologia , Criopreservação/instrumentação , Criopreservação/métodos , Crioprotetores , Temperatura Alta , Masculino , Análise do Sêmen/veterinária , Injeções de Esperma Intracitoplásmicas/veterinária , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Espermatozoides/ultraestrutura , Sus scrofa/genética
8.
Cryo Letters ; 35(5): 361-70, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25397950

RESUMO

BACKGROUND: Embryo cryopreservation has been used for the creation of genetic banks with diploid resources, and among different techniques, vitrification is considered as the most promising method. OBJECTIVE: The goal is to evaluate the major aspects of the existing vitrification techniques and to evaluate their efficacy in terms of embryo morphology. METHODS: Electronic searches in the PubMed and ScienceDirect databases were performed with the keyword combination: fish, embryo and vitrification. Pubmed retrieved 26 articles and Science Direct resulted in 464 articles. For this review, only studies that developed and tested vitrification protocols in fish embryos were included. Research regarding cryoprotectant toxicity and permeability were excluded. There were no restrictions on publication date or language. With these criteria, a total of ten articles were evaluated. RESULTS: In these articles, the major aspects to be considered for the development of new vitrification protocols are: the cryoprotectants' toxicity, the embryos' development stage, the exposure to and the permeability of the cryoprotectants, vitrification devices and vitrification-warning cycle. CONCLUSION: The survival were limited, however, the preservation of embryonic morphology after thawing indicates the possibility of preserving fish embryos via the vitrification technique.


Assuntos
Criopreservação/métodos , Criopreservação/veterinária , Crioprotetores/metabolismo , Embrião não Mamífero/fisiologia , Peixes/embriologia , Vitrificação , Animais , Criopreservação/instrumentação , Crioprotetores/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/embriologia
9.
Reprod Domest Anim ; 49(1): 79-84, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24033785

RESUMO

Three experiments were designed to test a solid-surface vitrification system for bovine in vitro-produced embryos and to develop a simple method of in-straw dilution after warming, which can be potentially used for direct transfer in the field. Experiment 1 evaluated embryo survival rates (i.e. re-expansion and hatching) after vitrification and warming in three different solutions: VS1 (20% ethylene glycol (EG) + 20% propanediol (PROH) + 0.25 m trehalose (Tr)), VS2 (20% EG + 1M Tr) or VS3 (30% EG + 0.75 m Tr). Re-expansion and hatching rates were higher (p < 0.05) for embryos vitrified in VS3 (72.2 ± 1.9 and 58.2 ± 0.8) than VS1 (64.4 ± 0.9 and 37.2 ± 2.5) or VS2 (68.5 ± 1.5 and 49.6 ± 1.0; p < 0.05). Experiment 2 was designed to compare two methods of vitrification: glass micropipettes or solid surface, using the VS1 or VS3 solutions. No significant differences were detected between the two methods; but re-expansion and hatching rates were higher (p < 0.05) with VS3 (73.5 ± 3.1 and 47.1 ± 2.1) than VS1 (63.3 ± 3.3 and 39.7 ± 2.8). In experiment 3, embryos were vitrified by solid surface in VS1 or VS3 solutions and cryoprotectants were diluted in-straw after warming in a TCM 199, 0.25 m sucrose solution or holding media. Survival rates of embryos vitrified in VS3 did not differ between those exposed to 0.25 m sucrose (74.7 ± 1.3 and 57.2 ± 2.2) or holding (77.3 ± 1.4 and 58.0 ± 2.5) medium after warming; however, survival rates of embryos vitrified in VS1 were higher (p < 0.05) in those exposed to 0.25 m sucrose (67.7 ± 2.3 and 47.0 ± 1.7) than holding medium (54.5 ± 1.0 and 27.7 ± 3.1). In conclusion, solid-surface vitrification using simplified EG-based solutions and in-straw dilution with holding media may be a practical alternative for cryopreservation and direct transfer of in vitro-produced bovine embryos.


Assuntos
Blastocisto/fisiologia , Bovinos/embriologia , Criopreservação/veterinária , Animais , Criopreservação/instrumentação , Criopreservação/métodos , Crioprotetores , Fertilização in vitro/veterinária , Temperatura Alta , Soluções , Sacarose
10.
Andrologia ; 46(9): 1055-62, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24313727

RESUMO

The effects of freezing technique and thawing protocol on thawed semen viability and fertility were studied. Ejaculates from 5 stallions (n = 25) were frozen by conventional or a fast-freezing technique. Frozen semen was thawed by two thawing protocols (37 °C 30 s(-1) or 75 °C 7 s(-1) ). Thawed semen was evaluated by progressive motility, vigour, morphology and plasma membrane integrity. Mares (n = 25) were inseminated with 300 (n = 11) or 150 (n = 14) million spermatozoa. A greater (P < 0.05) vigour and progressively motile spermatozoa were detected, respectively, at thawing and after 20 min post-thawing in the fast-freezing technique than in the conventional one. Plasma membrane integrity was also greater (P < 0.05) in semen frozen with the fast-freezing technique. Semen viability was not affected by thawing protocol. Pregnancy rate using the fast-freezing technique was 76% (19/25), and did not differ (P > 0.05) between insemination doses. We concluded that the 150 million progressively motile spermatozoa per dose using a deep-horn insemination maximises the use of equine semen. The fast-freezing technique, as compared to the conventional one, efficiently preserves the viability and fertilising capacity of spermatozoa, indicating a new method to improve the fertility of frozen equine semen.


Assuntos
Criopreservação/veterinária , Cavalos , Inseminação Artificial/veterinária , Preservação do Sêmen/veterinária , Animais , Sobrevivência Celular , Criopreservação/instrumentação , Criopreservação/métodos , Feminino , Fertilidade , Inseminação Artificial/métodos , Masculino , Gravidez , Sêmen/citologia , Preservação do Sêmen/instrumentação , Preservação do Sêmen/métodos
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