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1.
Food Chem ; 344: 128603, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33234437

RESUMO

Enzymatic lipophilization is an important process to extend the use of anthocyanins in lipidic media. In this work delphinidin 3-O-sambubioside (Dp3sam) isolated from Hibiscus sabdariffa L. flower was esterified with octanoic acid using Candida antarctica lipase B. The physical-chemical properties of the new lipophilic pigment were studied by UV-vis spectroscopy. Dp3sam with chloride, acetate and formate as counter ions were employed to study the lipophilization reaction. The hydrolysis of the reagent was avoided with a formate counter ion and the expected product was achieved with a noteworthy change of solubility. 1D and 2D NMR characterization of Dp3sam-C8 confirmed that the lipophilization took place at the primary alcohol of the glucoside moiety. Overall, the Dp3sam-C8 ester presents a stabilization of the quinoidal base (blue color) at neutral or moderate alkaline pH, which foresees a potential use of this pigment as a broad kind of industries on lipo-soluble formulations.


Assuntos
Antocianinas/análise , Ácidos Graxos/metabolismo , Proteínas Fúngicas/metabolismo , Hibiscus/química , Lipase/metabolismo , Acilação , Antocianinas/isolamento & purificação , Antocianinas/metabolismo , Biocatálise , Cromatografia Líquida de Alta Pressão , Cor , Dissacarídeos/química , Hibiscus/metabolismo , Concentração de Íons de Hidrogênio , Espectrometria de Massas , Extratos Vegetais/química , Extração em Fase Sólida
2.
J Fish Biol ; 91(2): 558-573, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28703291

RESUMO

The damselfish Chromis limbata is native to the Macaronesian Archipelagos (Azores, Madeira and Canaries) and the western coast of Africa between Senegal and Angola. During the austral summers of 2008 and 2009 the species was recorded for the first time in the south-western Atlantic Ocean around Campeche and Xavier Islands, in Florianópolis, Santa Catarina State, Brazil. Here, the progression of C. limbata in southern Brazilian waters is described using visual counts and genetic surveys and changes in the density of the native congener Chromis multilineata were also investigated. Underwater visual censuses of both Chromis species were carried out from 2009 to 2014. Chromis limbata tissue samples were collected and the mtDNA control region was sequenced and compared with mtDNA haplotypes from the natural range to confirm species identity, compare genetic diversity and to infer connectivity between newly established Brazilian populations. The Brazilian population of C. limbata increased significantly over the past 5 years and the effect on C. multilineata is still an open question, longer time-series data will be necessary to clarify possible interactions. The molecular analyses confirmed species identity, revealed strong haplotype connectivity among Brazilian study sites and showed a low genetic diversity in Brazil when compared with the native populations, suggesting few individuals started the invasion. Four hypotheses could explain this colonizing event: C. limbata was released by aquarium fish keepers; larvae or juveniles were transported via ship ballast water; the species has rafted alongside oil rigs; they crossed the Atlantic Ocean through normal larval dispersal or naturally rafting alongside drifting objects. The rafting hypotheses are favoured, but all four possibilities are plausible and could have happened in combination.


Assuntos
Peixes/fisiologia , Espécies Introduzidas , Animais , Oceano Atlântico , Sequência de Bases , Brasil , DNA Mitocondrial/química , Peixes/genética , Variação Genética , Haplótipos , Filogenia , Densidade Demográfica
3.
Radiologia ; 59(4): 306-312, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28495460

RESUMO

OBJECTIVE: To qualitatively and quantitatively explore the spectral study of focal liver lesions, comparing it with the usual polychromatic assessment with single-energy computed tomography. MATERIAL AND METHODS: We prospectively studied 50 patients with at least one focal liver lesion who were referred for abdominal multidetector computed tomography with intravenous contrast material. The portal phase was acquired with dual energy sources. The density of the lesions and of the surrounding liver parenchyma was measured both in the baseline polychromatic acquisition and in the posterior monochromatic reconstructions at 40 keV, 70 keV, and 140 keV. Spectral curves were traced and the dual-energy indices and contrast-to-noise ratio were calculated. Lastly, the quality of the images and the detectability of the lesions were assessed qualitatively. RESULTS: Densitometric differences between the different types of lesions (avascular and vascularized) and the liver were greater at low energy levels (left side of the spectral curve) than in the polychromatic evaluation. In the subjective assessment, the 40keV energy level had the greatest lesion detectability. CONCLUSIONS: Monochromatic spectral study with dual-energy computed tomography provides better lesion detectability at 40keV compared to that provided by the ordinary polychromatic evaluation.


Assuntos
Hepatopatias/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tomografia Computadorizada por Raios X/métodos
4.
Oxid Med Cell Longev ; 2015: 276039, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26301040

RESUMO

Parkinson's disease is a neurodegenerative disorder characterized by movement alterations caused by reduced dopaminergic neurotransmission in the nigrostriatal pathway, presumably by oxidative stress (OS). MPP(+) intrastriatal injection leads to the overproduction of free radicals (FR). The increasing formation of FR produces OS, a decline in dopamine (DA) content, and behavioral disorders. Epicatechin (EC) has shown the ability to be FR scavenger, an antioxidant enzyme inductor, a redox state modulator, and transition metal chelator. Acute administration of 100 mg/kg of EC significantly prevented (P < 0.05) the circling MPP(+)-induced behavior (10 µg/8 µL). Likewise, EC significantly (P < 0.05) reduced the formation of fluorescent lipid products caused by MPP(+). MPP(+) injection produced (P < 0.05) increased enzymatic activity of the constitutive nitric oxide synthase (cNOS). This effect was blocked with acute EC pretreatment. Cu/Zn-dependent superoxide dismutase (Cu/Zn-SOD) activity was significantly (P < 0.05) reduced as a consequence of MPP(+) damage. EC produced a slight increase (≈20%) in Cu/Zn-SOD activity in the control group. Such effects persisted in animals injured with MPP(+). The results show that EC is effective against MPP(+)-induced biochemical and behavioral damage, which is possible by an increase in Cu/Zn-SOD activity.


Assuntos
1-Metil-4-fenilpiridínio/toxicidade , Catequina/metabolismo , Cobre/metabolismo , Zinco/metabolismo , Animais , Catequina/farmacologia , Modelos Animais de Doenças , Masculino , Ratos , Ratos Wistar
5.
Regul Pept ; 159(1-3): 54-60, 2010 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-19800927

RESUMO

Food-restricted animals present metabolic adaptations that facilitate food-seeking behavior and decelerate energy utilization by reducing the hypothalamus-pituitary-thyroid (HPT) axis function. Stress by dehydration induces an anorexic behavior in rats, loss of weight and reduced food intake when compared to ad libitum fed animals, however these alterations are accompanied by HPT axis changes such as increased serum thyrotropin levels and enhanced expression of thyrotropin-releasing hormone (TRH) in the paraventricular nucleus of the hypothalamus, which is considered as anorexigenic peptide. In contrast, a pair-fed group conformed by forced-food-restricted animals (FFR) (eating the exact same amount of food as dehydration-induced anorexic rats--DIA rats) present decreased TRH mRNA levels. NPY synthesis in the arcuate nucleus and orexin-expressing neurons from the lateral hypothalamic area (LHA) are activated during food restriction. These brain structures project into PVN, suggesting that NPY and orexins are possible factors involved in TRHergic neuron activation in DIA rats. Leptin signaling is another likely factor to be involved in TRH differential expression. Therefore, to gain more insight into the regulation of the feeding behavior in the experimental models, we analyzed Y1, Y5, Ox1-R and Ob-R(b) mRNA levels in PVN and prepro-orexin in LHA, since their signaling to the PVN might be altering TRH synthesis and feeding in DIA animals. Prepro-orexinergic cells were activated in FFR animals; Ox1-R and Y1 expression was reduced in FFR vs. controls or DIA group. Compensatory changes in PVN receptor expression of some feeding-related peptides in anorexic rats may alter TRHergic neural response to energy demands.


Assuntos
Anorexia/metabolismo , Desidratação/metabolismo , Regulação da Expressão Gênica , Sistema Hipotálamo-Hipofisário , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neuropeptídeos/metabolismo , Sistema Hipófise-Suprarrenal , Receptores Acoplados a Proteínas G/biossíntese , Receptores de Neuropeptídeos/biossíntese , Animais , Anorexia/etiologia , Desidratação/complicações , Comportamento Alimentar , Leptina/metabolismo , Masculino , Desnutrição/metabolismo , Neurônios/metabolismo , Neuropeptídeo Y/metabolismo , Receptores de Orexina , Orexinas , Núcleo Hipotalâmico Paraventricular/metabolismo , Ratos , Ratos Wistar , Receptores de Neuropeptídeo Y/biossíntese , Transdução de Sinais , Tireotropina/biossíntese , Hormônio Liberador de Tireotropina/biossíntese
6.
Transplant Proc ; 39(7): 2431-3, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17889211

RESUMO

New ideas and experimental models for tissue and organ regeneration are urgently needed. There are several exciting challenges in the field of organogenesis that need to be defined. The integrated signals and molecular repertoires that shape the particular architecture of specific organs like the kidney or the liver are not completely understood yet. To develop a new scientific platform to be able to build up complex organs we have established a research program using basically Acellular Xenogeneic Isomorphic Matrices (AXIMs) and mesenchymal stem cells (MSCs) generating the necessary concepts for the definition, production, and application of the specific configurations of these matrices for organ regeneration. New and interesting pathways for MSC differentiation were identified. We believe that all extracellular matrices were created fundamentally equal or at least very similar in nature. We also believe that there are true "matrix superhighway configurations" with different three-dimensional geometrical architectures as well as biochemical, electrical, and molecular properties that are tissue and organ specific that influence cell differentiation and organogenesis and will be fundamental for the in vitro regeneration of complex organs for transplantation.


Assuntos
Transplante de Medula Óssea/métodos , Transplante de Órgãos/métodos , Animais , Transplante de Medula Óssea/fisiologia , Transplante de Medula Óssea/estatística & dados numéricos , Diferenciação Celular , Humanos , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Modelos Animais , Preservação de Órgãos/métodos , Transplante de Órgãos/estatística & dados numéricos , Coelhos , Regeneração , Suínos , Coleta de Tecidos e Órgãos/métodos , Transplante Heterólogo , Listas de Espera
7.
Transplant Proc ; 38(3): 967-9, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16647520

RESUMO

OBJECTIVES: Recent work has shown that human bone marrow contains mesenchymal stem cells (MSCs). However, little is known about their presence in peripheral blood. Since these cells are potentially responsible for tissue repair after injury, their number should be increased during these situations. To demonstrate their number during these situations, we measured MSCs in the peripheral blood of healthy donors and burn patients. MATERIALS AND METHODS: Blood samples were obtained from 15 acute burn patients and 15 healthy donors. We performed flow cytometric analysis, using a large monoclonal antibody panel: CD44, CD45, CD14, DR, CD34, CD19, CD13, CD29, CD105, CD1a, CD90, CD38, CD25. MSC phenotype was considered positive for CD44, CD13, CD29, CD90, and CD105, and negative for the other monoclonals. The testing was performed on day 3 after injury. We correlated the results with the age, sex, and size and type of burns. RESULTS: Cells expressing the MSC phenotype were detected in the peripheral blood of both groups. Noteworthy, compared with samples from healthy donors (0.0078 +/- 0.0044), blood obtained from burn patients showed a higher MSC percentage (0.1643 +/- 0.115; P < .001). The percentage of MSCs correlated with the size and severity of the burn. Increased values were also observed among younger patients. CONCLUSIONS: MSCs have an important role in regenerative processes of human tissues. We found cells phenotypically identical to MSCs circulating in physiological number in normal subjects, but in significantly higher amounts during acute large burns. Therefore, they may represent a previously unrecognized circulatory component to the process of skin regeneration.


Assuntos
Células da Medula Óssea/fisiologia , Queimaduras/fisiopatologia , Mesoderma/fisiologia , Células-Tronco/fisiologia , Cicatrização , Adulto , Antígenos CD/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Regeneração
8.
Transplant Proc ; 37(1): 292-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15808623

RESUMO

INTRODUCTION: We sought to use human mesenchymal stem cells (HMSC) for skin and spinal cord repair in mice. MATERIALS AND METHODS: Human bone marrow obtained from a young healthy donor was used to separate and culture human mesenchymal stem cells (HMSC). Ten mice were included in each of four groups. A full-thickness skin defect was surgically performed on all mice in groups 1 and 2. A transverse complete medullar section was performed in groups 3 and 4. Groups 1 and 3 received HMSC IV infusion and local HMSC polymer implant. Groups 2 and 4 received only the IV HMSC infusion. Five control animals from each group went through the same lesions but they didn't receive treatment. RESULTS: After local administration of HMSC into the fibrin polymer combined with the IV infusion of HMSC, there was no immune rejection; all skin defects healed without scar or retraction at a median time of 14 days. Sixty percent of the animals treated with IV infusion and polymer with HMSC simultaneously had improved neurological activities, while all control mice with spinal cord injury experiments died or perpetuated their paralysis with worsening muscular atrophy and increasing propensity to skin damage. CONCLUSIONS: HMSC are not immunologically reactive and can trespass species defense barriers. Animals treated with these cells repaired injuries better than controls. In this way we propose that universal HMSC from donors can be cultured, expanded, and cryopreserved to be used in human organ or tissue regeneration.


Assuntos
Mesoderma/citologia , Pele/lesões , Traumatismos da Medula Espinal/terapia , Transplante de Células-Tronco , Células-Tronco/citologia , Animais , Técnicas de Cultura de Células/métodos , Humanos , Camundongos , Transplante Heterólogo
10.
Arch Latinoam Nutr ; 50(2): 187-94, 2000 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-11048593

RESUMO

Proximate composition, fatty acid profile, essential aminoacid and minerals were determined in twelve fish species (armadillo, bocachico, cachama, carpeta, corvina, lisa, mero, merluza, pargo, robalo, tilapia and trucha). Proximate analysis: moisture, protein and ash, were performed using AOAC methodology, fat by Bligh and Dyer method, fatty acids by Gas Chromatography, aminoacid using High Performance Liquid Chromatography and minerals by spectrophotometric method. Results showed that moisture varies between 70.49% for Armadillo and 78.64% for Mero, protein between 18.70% for Merluza and 25.53 for Armadillo, ash between 0.94% for Mero and 2.13% for Carpeta and fat between 1.12% for Pargo and 6.15% for Cachama. Unsaturated fatty acids (omega 3) were the most common found for all the spices. Essential amino acids studied were present in all the spices. Tilapia (10.938 g/100 g of fish), Bocachico (9.231 g/100 g of fish) and Mero (8.738 g/100 g of fish) shown greater content of essential amino acids. Phosphorous was the most concentrated mineral with a mean value of 238.13 mg/100 g of fish followed by calcium with 42.11 mg/100 g of fish. It was concluded that all studied species are an excellent source of protein, omega 3 fatty acids and minerals.


Assuntos
Comércio , Ácidos Graxos/análise , Peixes , Minerais/análise , Aminoácidos Essenciais/análise , Animais , Valor Nutritivo , Venezuela
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