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1.
Osteoporos Int ; 24(5): 1647-61, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23104199

RESUMO

UNLABELLED: Arachidonic fatty acid (AA) induces adipogenesis in human mesenchymal stem cells cultures, and high concentrations inhibit osteoblastogenesis; whereas eicosapentaenoic and docosahexaenoic fatty acids do not induce adipogenesis and do not inhibit osteoblastogenesis. In mesenchymal stem cells, omega-6 arachidonic polyunsaturated fatty acid promotes the differentiation of adipocytes and inhibits the osteoblast differentiation. While omega-3 fatty acids do not affect the adipogenic differentiation their effects on osteoblastogenesis are less relevant. An increased ratio of omega-3/omega-6 fatty acid consumption can prevent bone mass loss. INTRODUCTION: Consumption of omega-3 may protect against osteoporosis since they may inhibit osteoclastogenesis. However, with aging, MSC in bone marrow are increasingly differentiated into adipocytes, reducing the number of osteoblasts. Products derived from omega-6 and omega-3 metabolism may affect MSC differentiation into osteoblasts and adipocytes. METHODS: Human MSC have been differentiated into osteoblasts or adipocytes in the presence of omega-6 (AA), or omega-3 (DHA and EPA), and osteoblastic and adipocytic markers have been analyzed. RESULTS: AA decreases the expression of osteogenic markers and the osteoprotegerin/receptor activator of nuclear factor kappa ß ligand gene expression ratio (opg/rankl). High concentrations of AA inhibit the mineralization and cause the appearance of adipocytes in MSC differentiating into osteoblasts to a higher extent than DHA or EPA. In MSC differentiated into adipocytes, AA increases adipogenesis, while DHA and EPA do not affect it. AA caused the appearance of adipocytes in undifferentiated MSC. The lipoxygenase gene (alox15b) is induced by omega-3 in MSC induced to osteoblasts, and by omega-6 in MSC induced to adipocytes. CONCLUSIONS: An increase in the intake of omega-3 respect to omega-6 may provide protection against the loss of bone mass, since omega-6 favors the osteoclastic activity by diminishing the opg/rankl gene expression in osteoblasts and promotes MSC differentiation into adipocytes, thus diminishing the production of osteoblasts.


Assuntos
Adipogenia/efeitos dos fármacos , Ácido Araquidônico/farmacologia , Ácidos Graxos Ômega-3/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipogenia/fisiologia , Adolescente , Adulto , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , Ácidos Graxos Ômega-6/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Lipoxigenase/biossíntese , Lipoxigenase/genética , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/citologia , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Osteoporose/patologia , Osteoporose/fisiopatologia , Ligante RANK/genética , Ligante RANK/metabolismo , Adulto Jovem
2.
Water Sci Technol ; 50(2): 91-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15344778

RESUMO

The removal of detergents from clarified wastewaters by activated petroleum coke (CAPA) was assessed. These substances, owing to their foamy properties, constitute a problem for ammonia removal by the air stripping process that could be installed in a wastewater treatment train to produce reclaimed water. CAPA was evaluated as a more economical alternative than a commercial activated carbon. Experimental work was divided in three stages: 1) production and characterisation of materials; 2) pretreatment of raw wastewater through the Fenton's reagent or coagulation-flocculation process with Al2(SO4)3; and 3) adsorption and bio-adsorption tests of clarified effluents. These tests were carried out in the laboratory in discontinuous and continuous reactors, the former by the "point-by-point" technique, with and without a previous fixing of bacteria, and the latter by the Rapid Small Scale Column Test. Detergents content, color, COD and UV254nm were measured in raw and treated wastewaters. Results show that the best pretreatment for the adsorption process was coagulation-flocculation rather than Fenton's method. Oxidation by this process decreased the adsorptive properties of detergents. Biomass fixed on the CAPA particles significantly increased the UV254nm and COD removal efficiencies (20% and 170% respectively). The breakthrough curves showed that CAPA could attain the expected detergents removal efficiency (66%) for the alum effluent.


Assuntos
Conservação dos Recursos Naturais , Detergentes/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Adsorção , Amônia/isolamento & purificação , Biomassa , Reatores Biológicos , Petróleo
3.
Water Sci Technol ; 49(1): 147-54, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14979550

RESUMO

The feasibility of using basaltic dust as a flocculant additive or coagulant aid for wastewater treatment was assessed in this research. The experimental study was divided into two stages: 1) physicochemical characterisation of the basaltic dust by applying standardised techniques, and 2) evaluation of this material as flocculant additive for the coagulation-flocculation of wastewater treated for reuse. Coagulation-flocculation experiments were carried out in the laboratory with a mixture of industrial and municipal wastewater samples collected from two points of the final discharge of the Mexico City sewerage system. Aluminium sulphate and lime were used as coagulants and the basaltic dust as flocculant additive, by applying the jar-test technique. The results of the corrosivity, reactivity, explosiveness, toxicity, inflammability and biological risk tests indicated that this material is classified as a non-hazardous waste (according to the Mexican legislation, NOM-052-ECOL-1993). The density, oxide content and particle size values of basaltic dust were similar to those reported for the flocculant additive denominated activated silica. The jar test results showed a positive effect of basaltic dust over the effluent and sludge qualities, to the extent that coagulant doses can be reduced 30% (from 150 mg/L to 110 mg/L of Al2(SO4)3).


Assuntos
Minerais/química , Silicatos/química , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Materiais de Construção , Corrosão , Poeira , Floculação , Teste de Materiais
4.
Acta Otorhinolaryngol Ital ; 22(4): 215-9, 2002 Aug.
Artigo em Italiano | MEDLINE | ID: mdl-12379042

RESUMO

The aim of this study was to test the effects of the iodine bromide water of the thermal baths of Salsomaggiore on patients suffering from specific nonseasonal rhinitis (Dermatophagoides Farinae and Dermatophagoides Pteronyssinus). The patients, 80 in all, were divided in two groups (group A and group B). All of the patients underwent rhinoscopic examination, anterior rhinomanometry, prick test, rast screening, total IgE assay together with that of the other immunoglobulins (IgA, IgM, IgG), mucociliary clearance evaluation and were asked to evaluate their degree of nasal obstruction, before and after 30 days of treatment. Group A carried out the experiment by applying endonasal Acqua Sal spray seven times a day for 30 days; group B used oily drops for the same time and with the same frequency. At the end of the trial period, the patients in group A showed a 100% improvement in their subjective perception of their symptomatology, in comparison with a 33% improvement in the control group. A characteristic decrease in the IgE and increase in the IgA was observed in the serum of the patients who had been treated with Acqua Sal spray. Iodine bromide water has a general and local anti-inflammatory effect, which is also due to the activation of the corticosurrenal system (with a relative increase in cortisol). The cleansing action of hypertonic water in the nasal cavities must also be cited, as it minimizes contact between the mucosa and allergens.


Assuntos
Balneologia/métodos , Brometos/uso terapêutico , Temperatura Alta , Imunoglobulina A/sangue , Imunoglobulina E/sangue , Iodetos/uso terapêutico , Rinite Alérgica Perene/tratamento farmacológico , Rinite Alérgica Perene/imunologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Depuração Mucociliar/imunologia
5.
Appl Environ Microbiol ; 65(3): 999-1004, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10049854

RESUMO

Various alkylbenzenes were depleted during growth of an anaerobic, sulfate-reducing enrichment culture with crude oil as the only source of organic substrates. From this culture, two new types of mesophilic, rod-shaped sulfate-reducing bacteria, strains oXyS1 and mXyS1, were isolated with o-xylene and m-xylene, respectively, as organic substrates. Sequence analyses of 16S rRNA genes revealed that the isolates affiliated with known completely oxidizing sulfate-reducing bacteria of the delta subclass of the class Proteobacteria. Strain oXyS1 showed the highest similarities to Desulfobacterium cetonicum and Desulfosarcina variabilis (similarity values, 98.4 and 98.7%, respectively). Strain mXyS1 was less closely related to known species, the closest relative being Desulfococcus multivorans (similarity value, 86.9%). Complete mineralization of o-xylene and m-xylene was demonstrated in quantitative growth experiments. Strain oXyS1 was able to utilize toluene, o-ethyltoluene, benzoate, and o-methylbenzoate in addition to o-xylene. Strain mXyS1 oxidized toluene, m-ethyltoluene, m-isoproyltoluene, benzoate, and m-methylbenzoate in addition to m-xylene. Strain oXyS1 did not utilize m-alkyltoluenes, whereas strain mXyS1 did not utilize o-alkyltoluenes. Like the enrichment culture, both isolates grew anaerobically on crude oil with concomitant reduction of sulfate to sulfide.


Assuntos
Derivados de Benzeno/metabolismo , Sulfatos/metabolismo , Bactérias Redutoras de Enxofre/isolamento & purificação , Xilenos/metabolismo , Alquilação , Anaerobiose , Composição de Bases , Biodegradação Ambiental , Meios de Cultura , DNA Bacteriano/química , DNA Bacteriano/genética , Genes de RNAr , Dados de Sequência Molecular , Oxirredução , Petróleo , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Bactérias Redutoras de Enxofre/genética , Bactérias Redutoras de Enxofre/crescimento & desenvolvimento , Bactérias Redutoras de Enxofre/metabolismo , Microbiologia da Água
6.
J Anim Sci ; 69(3): 879-85, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1648070

RESUMO

Voluntary intake and nutritive value of diets selected by goats grazing a shrubland at Marin county, N.L., Mexico were determined. Four esophageally cannulated Spanish female goats (average BW 35 kg), were used to collect extrusa samples monthly throughout 1 yr (June 1987 to May 1988). Organic matter intake (OMI) was estimated by total fecal collections from four castrated Spanish male goats (average BW 42 kg). Diets selected by goats were high in CP throughout the year (means = 18.9%). Available CP represented only about half the total CP. The ADF content of extrusa samples differed (P less than .05) among months, with high ADF values during winter months. Dietary lignin followed a similar pattern during the year. Goats consumed forage with sufficient amounts of Ca, Na, K, Mg, Cu, ZN, Mn, and Fe to meet requirements. The OMI of goats was different (P less than .05) among sampling periods. On the average, estimated OMI (means = 878.7 g/d) compared well with results of other studies in the area. Amounts of DE consumed by goats (1.1 Mcal DE/d) were not sufficient to meet requirements for maintenance plus low activity. High levels of browse in the diets presumably were responsible for low in vitro OM digestibility (means = 34.1%) throughout the year. Thus, productivity of range goats in these areas should be improved by supplementing with protein and energy.


Assuntos
Ração Animal , Ingestão de Alimentos , Cabras/metabolismo , Animais , Fibras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Fezes/química , Feminino , Lignina/administração & dosagem , Masculino , México , Minerais/administração & dosagem , Valor Nutritivo , Plantas Comestíveis , Estações do Ano
7.
J Biol Chem ; 262(34): 16590-5, 1987 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-3119589

RESUMO

In mammalian cells, a single major cellular protein (eukaryotic initiation factor 4D) is post-translationally modified by the conversion of a lysine residue into the unusual amino acid hypusine. This modification was reported to occur during mitogen-stimulated growth of lymphocytes but not during quiescence, suggesting that alternative forms of eukaryotic initiation factor 4D might play a role in the regulation of cell growth perhaps through the control of protein synthesis itself (Cooper, H. L., Park, M. H., and Folk, J. E. (1982) Cell 29, 791-797). We took advantage of the drastic changes in translational specificity which occur in heat-shocked cells of Drosophila melanogaster, and of the wide variations in translation rates which occur in response to alterations of growth media in the fungus Saccharomyces cerevisiae, to investigate the relationship between the intracellular level and state of modification of the hypusine-containing protein and the rate and specificity of translation. We also studied whether the hypusine residue in this protein might be subject to further modification or reversion to lysine. Under all conditions examined, the protein was remarkably long-lived. Furthermore, the hypusine persists in this protein as hypusine, without further modification or reversion to lysine. Thus, we observe no correlation between the state of cellular translation and the persistence or reversal of this protein's modification. In addition, the data imply that neither are the state of such key cellular processes as DNA replication, RNA transcription, or carbohydrate metabolism so correlated.


Assuntos
Lisina/análogos & derivados , Fatores de Iniciação de Peptídeos/biossíntese , Proteínas de Ligação a RNA , Animais , Drosophila melanogaster/metabolismo , Fluorometria , Temperatura Alta , Lisina/metabolismo , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , Saccharomyces cerevisiae/metabolismo , Esporos Fúngicos , Fator de Iniciação de Tradução Eucariótico 5A
8.
J Dermatol Surg Oncol ; 6(11): 939-43, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7462455

RESUMO

Clinical trials were carried out to determine if analgesia induced by nitrous oxide and oxygen could be useful as an adjunct to local anesthesia in dermatologic surgery. Patients readily accepted the procedure. The analgesia obtained reduced anxiety and pain, and no important adverse side effects were encountered. Overall, the agents and method are effective and have advantages over more commonly used agents and methods used as adjuncts to local anesthesia.


Assuntos
Anestésicos Locais , Procedimentos Cirúrgicos Dermatológicos , Óxido Nitroso/administração & dosagem , Oxigênio/administração & dosagem , Adolescente , Adulto , Idoso , Analgesia/instrumentação , Anestesia Local/instrumentação , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde
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