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1.
Cryo Letters ; 44(2): 110-108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37883160

RESUMO

BACKGROUND: The synergistic action among the different extracellular cryoprotectants could improve somatic cell quality after thawing and provide bases for the formation of biobanks for red-rumped agoutis. OBJECTIVE: This study evaluated the interactions among sucrose (SUC) and concentrations of serum fetal bovine (FBS) on the cryopreservation of somatic cells derived from red-rumped agoutis. MATERIALS AND METHODS: Cells were cryopreserved with 10% dimethyl sulfoxide and different concentrations of FBS (10%, 40%, and 90%) with or without 0.2 M SUC, totaling six comparison groups. Non-cryopreserved cells were used as a control. Cells were evaluated for viability, metabolic activity, proliferative activity, reactive oxygen species (ROS), mitochondrial membrane potential and apoptosis levels. RESULTS: No difference was observed among cryopreserved with DMSO containing (10FBS, 10FBS-SUC, 40FBS, 40FBS-SUC, 90FBS, 90FBS-SUC) and non-cryopreserved groups for viability, metabolic activity, proliferative activity, and ROS levels. Interestingly, only cells cryopreserved with 90% FBS and SUC maintained the mitochondrial membrane potential like the control. This indicates that at high concentrations of FBS, SUC contributes to the maintenance of this parameter in cryopreserved cells. Moreover, at concentrations of 10% and 40% of FBS, SUC contributed to the maintenance of viability evaluated by the levels of apoptosis evaluated after thawing. In summary, we verified that 90% FBS and 0.2 M SUC promote greater ability of cells after thawing. Additionally, SUC positively acts in cryopreservation solutions containing 10% and 40% FBS. CONCLUSION: This information is essential to an understanding of the mechanisms involved in the interactions of extracellular cryoprotectants in somatic cell cryopreservation solutions of red-rumped agoutis. DOI: 10.54680/fr23210110212.


Assuntos
Criopreservação , Dasyproctidae , Animais , Bovinos , Criopreservação/veterinária , Sacarose/farmacologia , Espécies Reativas de Oxigênio , Crioprotetores/farmacologia , Dimetil Sulfóxido/farmacologia , Sobrevivência Celular
2.
Mol Biosyst ; 11(11): 2955-63, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26281034

RESUMO

The mechanisms leading to the cell fate decision between apoptosis and senescence upon DNA damage are still unclear and have stochastic features. Cellular oxidative stress can generate DNA damage and activate the important mitogen-activated protein kinase 14 (p38MAPK) that is involved in pathologies like Alzheimer's disease. Based on experimental evidence we propose a simple network that might operate at the core of the cell control machinery for the choice between apoptosis and senescence involving the cross-talk between p38MAPK, the tumor suppressor protein p53 and the cyclin-dependent kinase inhibitor (p16INK4a). We have performed two types of analyses, deterministic and stochastic, exploring the system's parameter space, in the first, we calculated the fixed points of the deterministic model and, in the second, we numerically integrated the master equation for the stochastic version. The model shows a variety of behaviors dependent on the parameters including states of high expression levels of p53 or p16INK4a that can be associated with an apoptotic or senescent phenotype, respectively, in agreement with experimental data. In addition, we observe both monostable and bistable behavior (where bistability is a phenomenon in which two stable steady states coexist for a fixed set of control parameter values) which here we suggest to be involved in the cell fate decision problem.


Assuntos
Apoptose , Senescência Celular , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Modelos Biológicos , Proteína Supressora de Tumor p53/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Dano ao DNA , Cinética , Espécies Reativas de Oxigênio/metabolismo , Reprodutibilidade dos Testes , Processos Estocásticos
3.
J Helminthol ; 89(1): 19-27, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26262593

RESUMO

Pontoporia blainvillei (Gervais and d'Orbigny, 1844) is an endangered small cetacean endemic to South America with four Franciscana Management Areas (FMA) recognized as different population stocks. The role of the intestinal parasite Synthesium pontoporiae (Digenea: Brachycladiidae) as a possible biological marker to differentiate P. blainvillei stocks was evaluated using nuclear and mitochondrial DNA markers. Internal transcribed sequence 1 and 2 (ITS1 and ITS2) regions of S. pontoporiae did not show intraspecific variability. The mitochondrial NADH dehydrogenase subunit 3 (ND3) and cytochrome oxidase subunit I (COI) gene sequences suggested lack of population structure in S. pontoporiae and population expansion. The apparent panmixia of S. pontoporiae may be due to the high mobility of one or more of its intermediary hosts. Alternatively, it may be due to the small sample size. This result is incongruent with the previously proposed FMA.


Assuntos
Infecções por Cestoides/veterinária , Golfinhos/parasitologia , Variação Genética , Enteropatias Parasitárias/veterinária , Platelmintos/genética , Platelmintos/isolamento & purificação , Animais , Argentina , Brasil , Infecções por Cestoides/epidemiologia , Infecções por Cestoides/parasitologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Espécies em Perigo de Extinção , Proteínas de Helminto/genética , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Dados de Sequência Molecular , NADH Desidrogenase/genética , Filogenia , Platelmintos/classificação , Platelmintos/enzimologia
4.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;43(9): 816-820, Sept. 2010. ilus
Artigo em Inglês | LILACS | ID: lil-556858

RESUMO

The South American sea lion, Otaria flavescens, is widely distributed along the Pacific and Atlantic coasts of South America. However, along the Brazilian coast, there are only two nonbreeding sites for the species (Refúgio de Vida Silvestre da Ilha dos Lobos and Refúgio de Vida Silvestre do Molhe Leste da Barra do Rio Grande), both in Southern Brazil. In this region, the species is continuously under the effect of anthropic activities, mainly those related to environmental contamination with organic and inorganic chemicals and fishery interactions. This paper reports, for the first time, the genetic diversity of O. flavescens found along the Southern Brazilian coast. A 287-bp fragment of the mitochondrial DNA control region (D-loop) was analyzed. Seven novel haplotypes were found in 56 individuals (OFA1-OFA7), with OFA1 being the most frequent (47.54 percent). Nucleotide diversity was moderate (π = 0.62 percent) and haplotype diversity was relatively low (67 percent). Furthermore, the median joining network analysis indicated that Brazilian haplotypes formed a reciprocal monophyletic clade when compared to the haplotypes from the Peruvian population on the Pacific coast. These two populations do not share haplotypes and may have become isolated some time back. Further genetic studies covering the entire species distribution are necessary to better understand the biological implications of the results reported here for the management and conservation of South American sea lions.


Assuntos
Animais , DNA Mitocondrial/genética , Variação Genética/genética , Haplótipos/genética , Leões-Marinhos/genética , Brasil
5.
Rev Saude Publica ; 25(2): 121-8, 1991 Apr.
Artigo em Português | MEDLINE | ID: mdl-1784968

RESUMO

The infant mortality of children living in Botucatu, SP, Brazil, in 1987 is studied. In order to establish the risk profile for mortality, an additional risk factor (AR) was calculated on the basis some variables selected by means of a case control study. The results showed an AR for death of 15.58, 11.63, 8.50 and 4.04 respectively for the groups of preterm gestation, low birth, absence of household water supply and insufficient maternal educational level, respectively. It was shown that there is a significant difference in socio-economic status between the families of survivors and those of nonsurvivors. This fact suggests that the best strategy for overcoming the high infant mortality of the low income group is by improving their socio-economic condition so that they can enjoy similar capacity to consume goods and services, in quantity and quality, as the high socio-economic group.


Assuntos
Mortalidade Infantil , Brasil , Estudos de Casos e Controles , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Risco , Fatores Socioeconômicos
6.
Rev Saude Publica ; 17(3): 208-20, 1983 Jun.
Artigo em Português | MEDLINE | ID: mdl-6648303

RESUMO

PIP: The social determinants of maternal-child health in American countries are discussed on the basis of the analysis of several papers and official recommendation. Many of these do not place due emphasis on social factors. Indeed social factors are frequently put on the same level as biological ones. Thus, the resulting understanding is distorted. Conclusion and recommendations from such studies should be accepted with some caution since they do not get to the root of the problems. Diffferent social variables (such as maternal education or medical care) are often associated with biological ones (like birthweight or nutritional status). However, this cannot be taken to establish a cause-effect relationship among those variables, but only the simultaneous occurrence of the characteristic features of social class. The authors maintain that different social classes be recognized and compared since such a comparison can better explain the results in this field. The necessity of new research which takes into account the social factors as of greater importance than the biological ones is stressed. These would probably establish the social importance of the maternal-child health issue and avoid the recent purely technical guidelines and recommendations. (author's modified)^ieng


Assuntos
Proteção da Criança , Bem-Estar Materno , Programas Nacionais de Saúde , Brasil , Aleitamento Materno , Pré-Escolar , Feminino , Humanos , Lactente , Mortalidade Infantil , Recém-Nascido , Mortalidade Materna , Fatores Socioeconômicos , Urbanização
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