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1.
Rev. bras. farmacogn ; 28(4): 468-473, July-Aug. 2018. graf
Artigo em Inglês | LILACS | ID: biblio-958887

RESUMO

Abstract Flavones have the potential of being used as a dietary supplement for bone health promotion beyond calcium and vitamin D. Recent studies have showed that flavones enhanced bone formation and inhibited bone resorption by affecting osteoblast and osteoclast differentiation through various cell signaling pathways. In this study, we investigated the effects of a new flavone (2R,3S)-pinobanksin-3-cinnamate, isolated from the metabolites of the endophytic fungus Penicillium sp. FJ-1 of Acanthus ilicifolius L., Acanthaceae, on osteoblast differentiation by using MC3T3-E1 cells. It was observed that (2R,3S)-pinobanksin-3-cinnamate promoted osteoblast differentiation, as evidenced by increased mineralization process and alkaline phosphatase activity, as well as expression of genes encoding the bone differentiation. Moreover (2R,3S)-pinobanksin-3-cinnamate treatment upregulated the gene expression of wingless-type MMTV integration site family, bone morphogenetic protein and runt-related transcription factor 2, and protein expression of phosphor-Smad1/5/8, β-catenin and runt-related transcription factor 2 in MC3T3-E1 cells. The osteoblast differentiation effects induced by (2R,3S)-pinobanksin-3-cinnamate were attenuated by the bone morphogenetic protein antagonist Noggin, and wingless-type MMTV integration site family signaling pathway inhibitors Dickkopf-1. Co-treatment with adenosine 30,50-cyclic monophosphate and guanosine 30,50-cyclic monophosphate pathway inhibitors, H89 and KT5823, respectively, reversed the (2R,3S)-pinobanksin-3-cinnamate-induced activations of p-Smad1/5/8, β-catenin, and runt-related transcription factor 2. Our data demonstrated that (2R,3S)-pinobanksin-3-cinnamate promoted the osteoblast differentiation of MC3T3-E1 cells, at least partially through the adenosine 30,50-cyclic monophosphate and guanosine 30,50-cyclic monophosphate signaling pathways, providing the scientific rational to develop (2R,3S)-pinobanksin-3-cinnamate against bone loss-associated diseases.

2.
Front Genet ; 9: 223, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29988524

RESUMO

Halenia (Gentianaceae) originated from the mountain regions of East Asia, and diversified in America following long migrations via Beringia. While Halenia elliptica, one species of the genus in China, migrated toward high latitudes in China. Spur length of H. elliptica is highly variable. We examined the relationship between spur length and mating pattern along a latitude gradient. Field experiments were performed in two populations of H. elliptica, and we found that this species could produce seeds via both autonomous selfing and the aid of pollinators, suggesting a mixed mating system. In seven populations of H. elliptica along a latitudinal gradient, we found a trend of decrease in spur length with the increase of latitude. Based on molecular data from 11 microsatellite loci, we found that multilocus outcrossing rate decreased with the increase of latitude while the estimated inbreeding depression increased significantly, indicating that a high degree of inbreeding depression might have prevented evolution toward complete selfing in the high latitude populations with short spur length, and thus maintained mixed mating system of H. elliptica. Our results suggest that the mixed mating system of this species might be helpful in overcoming pollinator scarcity in newly colonized populations toward high latitudes after its origination in the mountain regions of China, and the decrease of spur length in the high latitude populations could result from reduced resource allocation to pollinator associated traits.

3.
Ecol Evol ; 7(2): 541-549, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28116051

RESUMO

Pollination systems and associated floral traits generally differ between core and marginal populations of a species. However, such differences are rarely examined in plants with a mixed wind- and bumblebee-pollination system, and the role of wind pollination during range expansion in ambophilous plants remains unclear. We compared floral traits and the contributions of bumblebee and wind pollination in refugium and marginal populations of the ambophilous plant Aconitum gymnandrum. We found that most floral traits differed between the two populations, and those traits associated with the shift to wind pollination were pronounced in the marginal population. Bumblebee visitation rates varied significantly, but were generally low in the marginal population. Wind pollination occurred in both populations, and the efficiency was lower than that of bumblebee pollination. Two types of pollen grains, namely round and fusiform pollen, were transported to a stigma by bumblebees and wind, but fusiform pollen contributed to wind pollination to a larger degree, especially in the marginal population. Our results suggest that wind pollination was enhanced by pollen dimorphism in the marginal population of A. gymnandrum, and wind pollination may provide reproductive assurance when bumblebee activity is unpredictable during range expansion, indicating that ambophily is stable in this species and shift in pollination system could be common when plants colonize new habitats.

4.
Mol Neurobiol ; 53(2): 1310-1321, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25631713

RESUMO

The development and/or progression of perihematomal edema (PHE) in patients with acute spontaneous intracerebral hemorrhage (ICH) vary substantially with different individuals. Although hematoma volume is a useful indicator for predicting PHE, its predictive power was not good at the early stage of ICH. Better predictors are urgently needed. In this study, we found that miR-130a was elevated in the serum of ICH patients and was an independent indicator positively associated with PHE volume within the first 3 days after onset. The R (2) was further evaluated when it is used in combination with hematoma mass. Serum miR-130a levels were associated with clinical outcome (National Institute of Health Stroke Scale (NIHSS) scores at day 14 and modified Rankin Scale (mRS) scores at day 90) only in patients with deep hematoma. Moreover, miR-130a was significantly increased in rat serum and perihematomal tissues and was in line with the change in brain edema. MiR-130a inhibitors reduced brain edema, blood-brain barrier (BBB) permeability, and increased neurological deficit scores, and miR-130a mimics increased monolayer permeability. Thrombin-stimulated brain microvascular endothelial cells (BMECs) were a main source of miR-130a under ICH. In the experimental model, the elevated miR-130a level was accompanied by the decreased caveolin-1 and increased matrix metalloproleinase (MMP)-2/9. Meanwhile, caveolin-1 (cav-1) was reduced by miR-130a mimics, accompanied by an increase in MMP-2/9 expression. The upregulated MMP-2/9 was then downregulated by cavtratin, a cav-1 scaffolding domain peptide. This regulation mechanism was authenticated in a thrombin-induced cellular ICH model. Our results suggest that serum miR-130a may serve as a useful early biomarker for monitoring post-ICH PHE and predicting prognosis and may be helpful in the decision-making of individualized therapy.


Assuntos
Edema Encefálico/sangue , Edema Encefálico/genética , Hemorragia Cerebral/sangue , Hemorragia Cerebral/genética , MicroRNAs/sangue , Doença Aguda , Animais , Comportamento Animal , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Encéfalo/patologia , Edema Encefálico/complicações , Edema Encefálico/enzimologia , Caveolina 1/metabolismo , Hemorragia Cerebral/complicações , Hemorragia Cerebral/enzimologia , Demografia , Modelos Animais de Doenças , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Feminino , Hematoma/sangue , Hematoma/complicações , Hematoma/genética , Humanos , Masculino , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Microvasos/patologia , Pessoa de Meia-Idade , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Trombina/farmacologia , Resultado do Tratamento , Regulação para Cima/genética
5.
World J Gastroenterol ; 19(4): 561-8, 2013 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-23382637

RESUMO

AIM: To evaluate the efficacy of reduced cathartic bowel preparation with 2 L polyethylene glycol (PEG)-4000 electrolyte solution and 10 mg bisacodyl enteric-coated tablets for computed tomographic colonography (CTC). METHODS: Sixty subjects who gave informed consent were randomly assigned to study group A, study group B or the control group. On the day prior to CTC, subjects in study group A were given 20 mL 40% wt/vol barium sulfate suspension before 3 mealtimes, 60 mL 60% diatrizoate meglumine diluted in 250 mL water after supper, and 10 mg bisacodyl enteric-coated tablets 1 h before oral administration of 2 L PEG-4000 electrolyte solution. Subjects in study group B were treated identically to those in study group A, with the exception of bisacodyl which was given 1 h after oral PEG-4000. Subjects in the control group were managed using the same strategy as the subjects in study group A, but without administration of bisacodyl. Residual stool and fluid scores, the attenuation value of residual fluid, and discomfort during bowel preparation in the three groups were analyzed statistically. RESULTS: The mean scores for residual stool and fluid in study group A were lower than those in study group B, but the differences were not statistically significant. Subjects in study group A showed greater stool and fluid cleansing ability than the subjects in study group B. The mean scores for residual stool and fluid in study groups A and B were lower than those in the control group, and were significantly different. There was no significant difference in the mean attenuation value of residual fluid between study group A, study group B and the control group. The total discomfort index during bowel preparation was 46, 45 and 45 in the three groups, respectively, with no significant difference. CONCLUSION: Administration of 10 mg bisacodyl enteric-coated tablets prior to or after oral administration of 2 L PEG-4000 electrolyte solution enhances stool and fluid cleansing ability, and has no impact on the attenuation value of residual fluid or the discomfort index. The former is an excellent alternative for CTC colorectum cleansing.


Assuntos
Bisacodil/uso terapêutico , Catárticos/uso terapêutico , Colonografia Tomográfica Computadorizada , Defecação/efeitos dos fármacos , Tomografia Computadorizada Multidetectores , Polietilenoglicóis/uso terapêutico , Irrigação Terapêutica/métodos , Administração Oral , Adulto , Idoso , Bisacodil/administração & dosagem , Bisacodil/efeitos adversos , Catárticos/administração & dosagem , Catárticos/efeitos adversos , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Valor Preditivo dos Testes , Estudos Prospectivos , Comprimidos com Revestimento Entérico , Resultado do Tratamento , Adulto Jovem
6.
Aviat Space Environ Med ; 80(9): 781-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19750875

RESUMO

BACKGROUND: The push-pull maneuver (PPM) can lead to loss of consciousness in pilots of high-performance aircraft. Modeling of the physical and physiological aspects of this phenomenon should allow improved countermeasures. METHODS: A structurally based mechanistic computer model was developed to incorporate dynamic carotid baroreflex responses and detailed modeling of vessel segments for different anatomic regions. The model was used to predict the effect of the PPM on cardiovascular responses and the protection afforded by extended coverage anti-G suits (ECGS) and neck pressure. RESULTS: The model was validated by comparing the simulation results with previously published experimental data obtained during centrifuge and tilt-table studies. Simulations of various PPM acceleration profiles indicated that +Gz tolerance was reduced in the presence of higher +Gz levels prior to the push phase, more -Gz levels during the push phase, and prolongation of the push phase. On the other hand, the onset rate for the two phases had only minor effects on +Gz tolerance. Model output suggested that improved protection could be provided by an ECGS with minimal inflation delay and a multilevel pressure schedule in which the leg bladders inflated to a higher pressure than the abdominal bladder. Modeling application of a 100-mmHg neck pressure during the push phase partly inactivated the carotid baroreflex, but induced only a small increase in tolerance. CONCLUSIONS: Mathematical modeling and simulation showed that +Gz tolerance for the PPM might be increased by improving the design and inflation schedule of the ECGS.


Assuntos
Aceleração , Fenômenos Fisiológicos Cardiovasculares , Simulação por Computador , Modelos Cardiovasculares , Adaptação Fisiológica , Barorreflexo , Artérias Carótidas/fisiologia , Centrifugação , Trajes Gravitacionais , Humanos , Teste da Mesa Inclinada
7.
Aviat Space Environ Med ; 78(2): 100-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17310880

RESUMO

BACKGROUND: It is difficult to assess how different combinations of recently developed anti-G protective equipment will affect +Gz tolerance and central hemodynamics during high G solely by centrifuge experiments. In this paper we report a mathematical model simulating the effects of various combinations on human circulatory response and +Gz tolerance, and its validation with published centrifuge data. METHODS: A structurally based mechanistic model incorporating cardio-pulmonary function, as well as a more detailed modeling of vessel segments for different anatomic regions, was established to simulate hemodynamic responses during high-G exposure and the protection afforded by various protective modalities, such as tilt-back seats, extended coverage anti-G suits (ECGS), and positive pressure breathing for +Cz (PBC). RESULTS: There were 43 pairs of human data from centrifuge trials and model outputs under the same or similar conditions that were compared. This comparison indicated that in 86% of cases the differences were less than 15%. From the model outputs, the best combinations which satisfied different protective needs, such as protection to +9 Gz, +10 Gz, and +12 Gz, respectively, could be discovered. They also suggested that while the combined protection of ECGS with PBG may be expressed as a simple addition of the two effects, the combined effect of the tilt-back seat with ECCGS and/or PBG seemed to be better fitted by a synergistic model. CONCLUSIONS: Comparisons with published centrifuge data have suggested the validity and confidence of the model developed. The benefits and limitations of the model for future high-G physiology and protection are discussed.


Assuntos
Circulação Sanguínea/fisiologia , Fenômenos Fisiológicos Cardiovasculares , Simulação por Computador , Trajes Gravitacionais , Modelos Cardiovasculares , Centrifugação , Desenho de Equipamento , Frequência Cardíaca , Humanos , Modelos Biológicos , Postura/fisiologia , Fenômenos Fisiológicos Respiratórios
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