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1.
Theriogenology ; 123: 30-36, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30273738

RESUMO

The earliest stages of embryo development are deeply influenced by reactive oxygen species (ROS), byproducts of the mitochondrial oxygen metabolism that play a key role as messengers in normal cell signal transduction and cell cycling. Despite its positive roles, the imbalance caused by the excess of ROS and an inefficient antioxidant system leads to oxidative stress, with negative consequences to the cell such as DNA damage, metabolic changes, mitochondrial stress and cell death. In the present work, crocetin - a natural antioxidant - was added to the culture media of bovine embryos to evaluate the efficiency of its antioxidant capability during embryo culture. Oocytes were in vitro matured (IVM) and fertilized according to standard protocols. Embryos were cultured at 38.5 °C under humidified air with 5% CO2, 7% O2, and 90% N2 in Synthetic Oviduct Fluid (SOF) medium supplemented with amino acids and either 5% of FBS (SOFaa) (control group) or SOFaa supplemented with 1  µM crocetin (crocetin group). After 5 days from the beginning of in vitro culture (IVC) (day 5 - D5), embryos were transferred to individual drops of culture media. At day 7 (D7), embryos were assessed by means of blastocyst rates, morphophysiological analyzes (total cell number, ROS and mitochondrial activity levels), transcript quantitation of 47 genes and metabolomic evaluation of the culture media by Raman spectroscopy. In the crocetin group blastocyst rates were higher and embryos had increased total cell number and decreased intracellular levels of ROS. These embryos also had upregulation of genes related with response to stress and lipid metabolism (ATF4, BAX, FOXO3, GADD45A, GPX1, GPX4, HSF1, SOD2, ACACA, SREBF1 and SREBF2). Raman spectroscopy corroborated these results indicating more active lipid and amino acid production in this group. The absence of crocetin in the culture media resulted in higher ROS level, as well as up regulation of genes related to DNA damage, stress response and energy metabolism (MORF4L2, SOD1, TXN, PFKP, PGK1 and PPARGC1A). In conclusion, crocetin supplementation during culture protects embryos from oxidative stress and influences the adaptive response to stress conditions, leading to an increase in both blastocyst yield and quality, as well as changes in transcriptomic and metabolic profile of in vitro produced bovine embryos.


Assuntos
Blastocisto/efeitos dos fármacos , Carotenoides/farmacologia , Bovinos/embriologia , Desenvolvimento Embrionário/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Transcriptoma , Animais , Antioxidantes/farmacologia , Técnicas de Cultura Embrionária/veterinária , Vitamina A/análogos & derivados
2.
J Phys Condens Matter ; 29(20): 205401, 2017 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-28346216

RESUMO

The oxyborate Fe3O2BO3 presents a charge density wave (CDW) transition close to room temperature. As we show here, this is associated with a well defined anomaly in the specific heat. Below this transition, when applying in a single crystal of Fe3O2BO3 a DC voltage above a temperature dependent threshold, a high current is liberated in this material. We study the conduction in single crystals of Fe3O2BO3 with voltage applied parallel and perpendicular to the crystallographic c axis direction. The observed currents are attributed to the depinning of charge ordered domains above a threshold voltage V T2 that gives rise to a collective conduction due to coherent domains. Compliance limited DC data shows that above a lower threshold voltage depinning is smooth and follows a power law scaling. Similar depinning with power law scaling is also revealed in the AC conductivity.

3.
Br J Nutr ; 114(2): 257-64, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26079483

RESUMO

The present cross-sectional study assessed the potential relationships of carotenoid intake with lipid and oxidative stress markers in middle-aged men. A total of 296 apparently healthy middle-aged men (mean age 50.5 (SD 5.0) years, BMI 25.8 (SD 3.5) kg/m(2)) were recruited to participate in the study. Dietary intake, anthropometry, blood pressure, lifestyle features, blood and urine biomarkers were assessed using validated procedures. The lipid markers included NEFA, Castelli index, and TAG:HDL ratio; oxidative stress markers included urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG), 8-iso-PGF2α and plasma oxidised-LDL (ox-LDL). We observed a significant inverse association (P < 0.05) between NEFA concentrations and consumption of lutein plus zeaxanthin, ß-carotene, α-carotene and total carotenoid, while Castelli index was negatively associated with daily intake of lycopene, ß-carotene and total carotenoids. Regarding oxidative stress biomarkers, urinary 8-OHdG and ox-LDL concentrations were also inversely associated (P < 0.05) with consumption of lycopene, lutein plus zeaxanthin, ß-carotene, α-carotene and total carotenoids, regardless of confounding variables. Moreover, there was a negative association of urinary 8-iso-PGF2α concentration with dietary lutein plus zeaxanthin (ß - 0.135, 95% CI - 0.268, - 0.001), ß-carotene (ß - 0.156, 95% CI - 0.277, - 0.034) and with the sum of all carotenoids (ß - 0.189, 95% CI - 0.333, - 0.046). In conclusion, total daily carotenoid intake based on five investigated carotenoid types (ß-cryptoxanthin, lycopene, lutein plus zeaxanthin, ß-carotene and α-carotene) was inversely associated with relevant lipid and oxidative stress markers in middle-aged men, with emphasis on ß-carotene that was negatively associated with five of the six lipid and oxidative stress markers evaluated in the present study.


Assuntos
Carotenoides/administração & dosagem , Dano ao DNA/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Biomarcadores/sangue , Biomarcadores/urina , Índice de Massa Corporal , Carotenoides/sangue , Estudos Transversais , Desoxiguanosina/análogos & derivados , Desoxiguanosina/urina , Dinoprosta/análogos & derivados , Dinoprosta/urina , Humanos , Estilo de Vida , Lipoproteínas LDL/sangue , Luteína/administração & dosagem , Luteína/sangue , Licopeno , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Estresse Oxidativo/efeitos dos fármacos , Inquéritos e Questionários , Zeaxantinas/administração & dosagem , Zeaxantinas/sangue , beta Caroteno/administração & dosagem , beta Caroteno/sangue
4.
Toxicon ; 47(3): 313-21, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16373074

RESUMO

Crotalus durissus terrificus snake venom and its major toxin, crotoxin or type II PLA2 subunit of this toxin, induce an inhibitory effect on spreading and phagocytosis in 2h incubated macrophages. The involvement of arachidonate-derived mediators on the inhibitory action of the venom or toxins on rat peritoneal macrophage phagocytosis was presently investigated. Peritoneal cells harvested from naive rats and incubated with the venom or toxins or harvested from the peritoneal cavity of rats pre-treated with the toxins were used. Zileuton, a 5-lipoxygenase inhibitor but not indomethacin, a cyclooxygenase inhibitor, given in vivo and in vitro abolished the inhibitory effect of venom or toxins on phagocytosis. Resident peritoneal macrophages incubated with the venom or toxins showed increased levels of prostaglandin E2 and lipoxin A4, with no change in leukotriene B4. These results suggest that lipoxygenase-derived eicosanoids are involved in the inhibitory effect of C.d. terrificus venom, crotoxin or PLA2 on macrophage phagocytosis.


Assuntos
Venenos de Crotalídeos/farmacologia , Crotalus , Crotoxina/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Animais , Venenos de Crotalídeos/química , Crotoxina/química , Relação Dose-Resposta a Droga , Eicosanoides , Lipoxigenase , Masculino , Ratos , Ratos Wistar
5.
Toxicon ; 43(7): 801-10, 2004 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15284014

RESUMO

In Brazil, the Crotalus durissus terrificus subspecie is the most studied, particularly concerning its crotoxin. Crotoxin is the major toxic component of the South American rattlesnake Crotalus durissus venom. It is composed of two different subunits, CA called crotapotin and CB weakly toxic phospholipase A2 with high enzymatic activity. In this paper, we decided to make a study of the main toxic characteristics of crotoxin (CTX) and CB fraction from the other subspecies, Crotalus durissus cascavella and of Crotalus durissus collilineatus, in comparison with those of C. d. terrificus. Ours results have shown that the venoms presented similar chromatographic profiles and the purified fractions were free of contaminants. Regarding the toxic activities, the DL50 of the crotoxins showed no significant differences between the subspecies. The smaller toxicity of CB indicated that the toxicity of the crotoxin complex depends on the interaction between CA and CB. CTX and fraction CB of the three species of Crotalus showed negligible proteolytic activity. C. d. terrificus CTX presented higher PLA2 activity when compared with the others two subspecies. The oedema induced by CB developed later than the CTX and reached its peak 3 h after the injection. The myotoxic activity was determined by assaying serum CK levels. Mice injected with CTX of C. d. terrificus presented greater myotoxic activity compared to the others. The myotoxic activity of CB from the three subspecies was lower than the activity of the crotoxin, reinforcing the idea that the fraction CA increases the toxicity of CB.


Assuntos
Crotalus , Crotoxina/toxicidade , Fosfolipases A/toxicidade , Análise de Variância , Animais , Brasil , Caseínas/metabolismo , Cromatografia por Troca Iônica , Creatina Quinase/sangue , Crotoxina/metabolismo , Edema/induzido quimicamente , Eletroforese em Gel de Poliacrilamida , Dose Letal Mediana , Camundongos , Camundongos Endogâmicos BALB C , Fosfolipases A/metabolismo , Fosfolipases A2 , Fatores de Tempo , Testes de Toxicidade Aguda
6.
Toxicon ; 41(7): 899-907, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12782091

RESUMO

Previous work of our group demonstrated that Crotalus durissus terrificus venom has a dual effect on macrophage function: it inhibits spreading and phagocytosis and stimulates hydrogen peroxide and nitric oxide production, antimicrobial activity and glucose and glutamine metabolism of these cells. Crotalid venom also induces analgesia and this effect is mediated by opioid receptors. The involvement of opioidergic mechanism and the determination of the active component responsible for the inhibitory effect of crotalid venom on macrophage function were investigated. The venom reduced the spreading and phagocytic activities of peritoneal macrophages. This effect was observed in vitro, 2 h after incubation of resident peritoneal macrophages with the venom, and in vivo, 2 h after subcutaneous injection of the venom. The inhibition of phagocytosis was not modified by naloxone, an antagonist of opioid receptors. Venom neutralization with crotalid antivenom abolished the inhibitory effect of the venom, indicating that venom toxins are involved in this effect. Crotoxin, the main toxin of crotalid venom, s.c. injected to rats or added to the medium of peritoneal cell incubation, inhibited macrophage function in a similar manner to that observed for crude venom. The present results suggest that crotoxin causes a direct inhibition of macrophage spreading and phagocytic activities and may contribute to the inhibitory effect of crotalid venom on macrophage function.


Assuntos
Crotalus , Crotoxina/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Fagocitose/efeitos dos fármacos , Animais , Antivenenos/farmacologia , Candida albicans/fisiologia , Células Cultivadas , Crotoxina/administração & dosagem , Crotoxina/química , Crotoxina/imunologia , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Injeções Subcutâneas , Macrófagos Peritoneais/metabolismo , Masculino , Naloxona , Testes de Neutralização , Óxido Nítrico/biossíntese , Ratos , Ratos Wistar , Ovinos
8.
Rev Saude Publica ; 27(3): 204-9, 1993 Jun.
Artigo em Português | MEDLINE | ID: mdl-8115835

RESUMO

The proposal for a visual acuity test (A.V.) arose from a survey conducted among School Children of the "Ciclo Básico (C.B.)" i.é., the first two years of Elementary School in S. Carlos, S. Paulo State, Brazil. Nine schools participated in this study. The teachers were properly trained to apply the A. V. and squinting tests according to a standardized procedure. Of 2,025 children tested, 88.1% showed levels of A. V. higher than 0.8, and a squinting prevalence of 2.17%. When the application of the test was over, each school presented its proposals for the systematical application of such tests. These proposals had a common point: the test should be applied by the teachers themselves under the supervision of the coordinators of the C. B. The school nurse would be responsible for giving overall assistance to all the activities of the program at all levels.


Assuntos
Transtornos da Visão/prevenção & controle , Seleção Visual/organização & administração , Brasil , Criança , Feminino , Humanos , Masculino , Programas de Rastreamento , Serviços de Saúde Escolar , Estrabismo/prevenção & controle , Acuidade Visual
9.
Arq Neuropsiquiatr ; 50(3): 329-33, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1308411

RESUMO

Eleven out of 36 autopsied cases of Wernicke's encephalopathy had developed coma. None of these patients had the diagnosis during life. There were six men and five women with ages ranging from 26 to 50 years (mean 36.6). Seven of these patients were heavy drinkers, three exhibited signs of severe malnutrition, whereas one was being evaluated for a disseminated gastric cancer and one was in treatment of hyperemesis gravidarum. Two patients were brought to the hospital after found unconscious at home. Neuropathological examination disclosed gross changes in the mammillary bodies in eight cases and microscopic changes in all cases. In one case there was atrophy of the anterior superior part of the vermis. Petechial hemorrhages were observed particularly in the walls of the third ventricle. Microscopically there were in addition to hemorrhages, glial proliferation, endothelial hypertrophy and necrosis of nerve cells and myelin. Central pontine myelinolysis was observed in one case. Wernicke's encephalopathy is a clinically underdiagnosed condition. Coma may mask its classical clinical picture or even be the sole manifestation. Although coma points to a poor outlook it may be reversed by thiamine administration. Any patient with coma of unknown etiology should be given parenteral thiamine.


Assuntos
Coma/patologia , Encefalopatia de Wernicke/patologia , Adulto , Alcoolismo/complicações , Coma/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Encefalopatia de Wernicke/complicações , Encefalopatia de Wernicke/mortalidade
10.
J Clin Neuroophthalmol ; 9(4): 236-40; discussion 241, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2531160

RESUMO

We report here a case of Schilder's myelinoclastic diffuse sclerosis in a 14-year-old girl with sudden bilateral visual loss. Computed tomographic scan showed two large symmetrical lesions in the occipital lobes and a smaller hypodense area in the frontal lobe. Cerebrospinal fluid examination revealed increased immunoglobulin G fraction with the presence of oligoclonal bands. Ultrastructural study of a biopsy specimen disclosed a demyelinating disorder with no cytoplasmic inclusions. Steroid treatment was followed by a dramatic response, with almost complete visual recovery and shrinkage of the lesions.


Assuntos
Dexametasona/uso terapêutico , Esclerose Cerebral Difusa de Schilder/diagnóstico , Lobo Occipital/diagnóstico por imagem , Transtornos da Visão/etiologia , Adolescente , Esclerose Cerebral Difusa de Schilder/complicações , Esclerose Cerebral Difusa de Schilder/tratamento farmacológico , Feminino , Humanos , Lobo Occipital/fisiopatologia , Tomografia Computadorizada por Raios X , Transtornos da Visão/fisiopatologia
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