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1.
Appetite ; 168: 105698, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34547350

RESUMO

The present study investigates how consumers perceive organic-certified versus non-certified natural foods relative to each other, compares motives for purchasing them, and explores how these influence purchase behaviors toward the combined natural foods category. Analysis of a USA shopper survey finds there are still pronounced differences in perceptions, trust, and willingness to pay. Some 57% of respondents agree at a level of 4 or 5 (out of 5) that there are differences between organic-certified and non-certified natural foods. Mean levels of trust for natural and certified organic labels are 2.67 and 3.50 respectively. Consumers are willing to pay price premiums of 25% and 37% for non-certified and organic-certified respectively. Results show shoppers have shared and different motives for purchasing. No added growth hormones and No artificial additives or preservatives are the two reasons that appear in the top five for purchasing organic-certified and non-certified foods. Other top five reasons for organic-certified are agriculture oriented: No chemical pesticides, herbicides, or fertilizers, No antibiotics, and USDA organic certification. Other top five reasons for non-certified are processing oriented: No artificial flavors, colors, or sweeteners, Minimal processing, and No high fructose corn syrup. Some of these differences influence intended purchase behaviors. Trust in organic-certified and non-certified labels affects willingness to pay. Four of the organic-certified attributes have a relationship with one or more of purchase frequency, number of items per trip, weekly spending, and willingness to pay.


Assuntos
Comportamento do Consumidor , Alimentos Orgânicos , Certificação , Preferências Alimentares , Humanos , Motivação
2.
Biol Trace Elem Res ; 161(1): 123-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25074429

RESUMO

The behavior of fluoride ions in biological systems has advantages and problems. On one hand, fluoride could be a mitogenic stimulus for osteoblasts. However, high concentrations of this element can cause apoptosis in rat and mouse osteoblasts. Toward an understanding of this effect, we examined the role of sodium fluoride (NaF) in two mouse calvaria osteoblasts during the mineralization process. The animals used were C3H/HeJ (C3) and C57BL/6J (B6) mice. The calvaria cells were cultured for 28 days in the presence of several doses of NaF (0, 5, 10, 25, 50, and 75 µM), and we performed the assays: mineralized nodule measurements, alkaline phosphatase (ALP) activity, determination of type I collagen, and matrix metalloproteinase-2 (MMP-2) activity. The results showed no effects on alkaline phosphatase activity but decreased mineralized nodule formation. In B6 cells, the NaF effect was already seen with 10 µM of NaF and a greater increase of cellular type I collagen, and MMP-2 activity was upregulated after 7 days of NaF exposure. C3 osteoblasts showed a reduction in the mineralization pattern only after 50 µM of NaF with a slight increase of type I collagen and downregulation of MMP-2 activity during the mineralization period. In conclusion, fluoride affects the production and degradation of the extracellular matrix during early onset and probably during the mineralization period. Additionally, the genetic factors may contribute to the variation in cell response to fluoride exposure, and the differences observed between the two strains could be explained by an alteration of the bone matrix metabolism (synthesis and degradation).


Assuntos
Calcificação Fisiológica/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Fluoreto de Sódio/farmacologia , Fosfatase Alcalina/metabolismo , Análise de Variância , Animais , Animais Recém-Nascidos , Western Blotting , Células Cultivadas , Colágeno Tipo I/metabolismo , Relação Dose-Resposta a Droga , Metaloproteinase 2 da Matriz/metabolismo , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Osteoblastos/citologia , Osteoblastos/metabolismo , Especificidade da Espécie
3.
PLoS One ; 8(5): e63260, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23667596

RESUMO

BACKGROUND: Ventral root avulsion is an experimental model of proximal axonal injury at the central/peripheral nervous system interface that results in paralysis and poor clinical outcome after restorative surgery. Root reimplantation may decrease neuronal degeneration in such cases. We describe the use of a snake venom-derived fibrin sealant during surgical reconnection of avulsed roots at the spinal cord surface. The present work investigates the effects of this fibrin sealant on functional recovery, neuronal survival, synaptic plasticity, and glial reaction in the spinal motoneuron microenvironment after ventral root reimplantation. METHODOLOGY/PRINCIPAL FINDINGS: Female Lewis rats (7 weeks old) were subjected to VRA and root replantation. The animals were divided into two groups: 1) avulsion only and 2) replanted roots with fibrin sealant derived from snake venom. Post-surgical motor performance was evaluated using the CatWalk system twice a week for 12 weeks. The rats were sacrificed 12 weeks after surgery, and their lumbar intumescences were processed for motoneuron counting and immunohistochemistry (GFAP, Iba-1 and synaptophysin antisera). Array based qRT-PCR was used to evaluate gene regulation of several neurotrophic factors and receptors as well as inflammatory related molecules. The results indicated that the root reimplantation with fibrin sealant enhanced motor recovery, preserved the synaptic covering of the motoneurons and improved neuronal survival. The replanted group did not show significant changes in microglial response compared to VRA-only. However, the astroglial reaction was significantly reduced in this group. CONCLUSIONS/SIGNIFICANCE: In conclusion, the present data suggest that the repair of avulsed roots with snake venom fibrin glue at the exact point of detachment results in neuroprotection and preservation of the synaptic network at the microenvironment of the lesioned motoneurons. Also such procedure reduced the astroglial reaction and increased mRNA levels to neurotrophins and anti-inflammatory cytokines that may in turn, contribute to improving recovery of motor function.


Assuntos
Adesivo Tecidual de Fibrina/farmacologia , Neurônios Motores/patologia , Regeneração Nervosa/efeitos dos fármacos , Radiculopatia/fisiopatologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Raízes Nervosas Espinhais/patologia , Sinapses/patologia , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Regulação para Baixo/efeitos dos fármacos , Feminino , Adesivo Tecidual de Fibrina/uso terapêutico , Proteína Glial Fibrilar Ácida/metabolismo , Proteínas dos Microfilamentos/metabolismo , Neurônios Motores/efeitos dos fármacos , Fatores de Crescimento Neural/biossíntese , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Neuroglia/patologia , Fármacos Neuroprotetores/farmacologia , Pressão , Implantação de Prótese , Radiculopatia/tratamento farmacológico , Ratos , Ratos Endogâmicos Lew , Venenos de Serpentes/química , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Raízes Nervosas Espinhais/efeitos dos fármacos , Raízes Nervosas Espinhais/fisiopatologia , Sinapses/efeitos dos fármacos , Sinaptofisina/metabolismo , Regulação para Cima/efeitos dos fármacos , Cicatrização/efeitos dos fármacos
4.
Environ Manage ; 45(2): 274-83, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20069301

RESUMO

Shaded perennial agroforestry systems contain relatively high quantities of soil carbon (C) resulting from continuous deposition of plant residues; however, the extent to which the C is sequestered in soil will depend on the extent of physical protection of soil organic C (SOC). The main objective of this study was to characterize SOC storage in relation to soil fraction-size classes in cacao (Theobroma cacao L.) agroforestry systems (AFSs). Two shaded cacao systems and an adjacent natural forest in reddish-yellow Oxisols in Bahia, Brazil were selected. Soil samples were collected from four depth classes to 1 m depth and separated by wet-sieving into three fraction-size classes (>250 microm, 250-53 microm, and <53 microm)-corresponding to macroaggregate, microaggregate, and silt-and-clay size fractions-and analyzed for C content. The total SOC stock did not vary among systems (mean: 302 Mg/ha). On average, 72% of SOC was in macroaggregate-size, 20% in microaggregate-size, and 8% in silt-and-clay size fractions in soil. Sonication of aggregates showed that occlusion of C in soil aggregates could be a major mechanism of C protection in these soils. Considering the low level of soil disturbances in cacao AFSs, the C contained in the macroaggregate fraction might become stabilized in the soil. The study shows the role of cacao AFSs in mitigating greenhouse gas (GHG) emission through accumulation and retention of high amounts of organic C in the soils and suggests the potential benefit of this environmental service to the nearly 6 million cacao farmers worldwide.


Assuntos
Agricultura , Cacau , Carbono/análise , Agricultura Florestal , Solo/análise , Brasil
5.
Acta cir. bras ; 17(1): 4-11, jan.-fev. 2002. ilus, graf
Artigo em Inglês | LILACS | ID: lil-306248

RESUMO

End-to-end conventional arterial anastomosis is time consuming, requires prolonged clamping times and is associated with focal necrosis, granulocyte infiltration and subsequently, fibrosis and calcification of the arterial wall. Fibrin glue as an alternative for microarterial anastomosis may obviate these lesions, with less adherence to adjacent tissues and better coaptation of the arterial margins. OBJECTIVE: In this study we compared the healing process of conventional to fibrin glue end-to-end anastomosis in larger arteries. METHODS: In 22 rabbits, both carotid arteries were cross sectioned and repaired by end-to-end anastomosis with 4 interrupted sutures and fibrin glue in one side (GI) and with 8 conventional interrupted sutures in the other side (G2). After 3 and 15 days, the animals were randomly allocated for tensile strength, hydroxyproline determination (8 animals), and histologic analysis of the anastomosis (3 animals). Conventional staining procedures (hematoxylin-eosin and Masson methods) and picrosirius red polarization (PSP) technique for collagen type determination were employed. RESULTS: From 3 to 15 days, the tensile strength increased in both groups, from 280.0ñ 32.6 g to 432.2ñ 131.2g in Group I and from 221.4ñ 72.4g to 452.2ñ 132.0g in Group 2 (p<0.001), with no statistical difference between the groups in each period of the study. The hydroxyproline content, expressed as hydroxyproline /protein ratio, varied from 0.0816 ñ 0.0651 to 0.0622 ñ 0.0184 in Group l and from 0.0734 ñ 0.0577 to 0.0460 ñ 0.0271 in Group 2, with no significant difference between periods and groups (p>0.05). Histology showed slight increase of inflammatory and reparative reactions in Group 2. PSP technique demonstrated predominant type I collagen in relation to type III collagen in the anastomosis of both groups, with no significant difference between them. CONCLUSION: Fibrin glue was less harmful to the arterial wall than conventional suture. Even using less sutures in fibrin glue anastomosis, similar tensile strength and healing characteristics were noted in both groups. Completion times for the fibrin glue group was significantly greater than for the conventional anastomosis.


Assuntos
Animais , Coelhos , Anastomose Cirúrgica/métodos , Artérias Carótidas/cirurgia , Adesivo Tecidual de Fibrina , Hidroxiprolina , Adesivos Teciduais , Cicatrização , Suturas
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