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1.
J Healthc Qual Res ; 39(2): 89-99, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38195377

RESUMO

INTRODUCTION: Today, primary care professionals' (PCPs) perspectives on hospital quality are unknown when evaluating hospital quality priorities. The aims of the present study were to identify key healthcare quality attributes from PCPs' perspective, to validate an instrument that measures PCPs' experiences of healthcare quality multidimensionally and to define hospital quality priorities based on PCPs' experiences. MATERIAL AND METHODS: Focus groups with PCPs were conducted to identify quality attributes through a qualitative in-depth analysis. A multicentre study of 18 hospitals was used to quantitatively assess construct, discriminant and criterion validity of the FlaQuM-Quickscan, an instrument that measures 'Healthcare quality for patients and kin' (part 1) and 'Healthcare quality for professionals' (part 2). To set quality priorities, scores on quality domains were analyzed descriptively and between-hospital variation was examined by evaluating differences in hospitals' mean scores on the quality domains using one-way Analysis of Variance (ANOVA). RESULTS: Identified key attributes largely corresponded with Lachman's multidimensional quality model. Including 'Communication' as a new quality domain was recommended. The FlaQuM-Quickscan was completed by 550 PCPs. Confirmatory factor analyses showed reasonable to good fit, except for the Root Mean Square Error of Approximation (RMSEA) in part 2. The 'Equity' domain scored the highest in parts 1 and 2. Domains 'Kin-centred care' and 'Accessibility and timeliness' scored the lowest in part 1 and 'Resilience' and 'Partnership and co-production' in part 2. Significant variation in hospitals' mean scores was observed for eleven domains in part 1 and sixteen domains in part 2. CONCLUSIONS: The results gained a better understanding of PCPs' perspective on quality. The FlaQuM-Quickscan is a valid instrument to measure PCPs' experiences of hospital quality. Identified priorities indicate that hospital management should focus on multifaceted quality strategies, including technical domains, person-and kin-centredness, core values and catalysts.


Assuntos
Hospitais , Qualidade da Assistência à Saúde , Humanos , Análise de Variância , Grupos Focais , Atenção Primária à Saúde
2.
Mol Cell Biol ; 10(9): 4518-23, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2201893

RESUMO

Addition of glucose or related fermentable sugars to derepressed cells of the yeast Saccharomyces cerevisiae triggers a RAS-mediated cyclic AMP (cAMP) signal that induces a protein phosphorylation cascade. In yeast mutants (tpk1w1, tpk2w1, and tpk3w1) containing reduced activity of cAMP-dependent protein kinase, fermentable sugars, as opposed to nonfermentable carbon sources, induced a permanent hyperaccumulation of cAMP. This finding confirms previous conclusions that fermentable sugars are specific stimulators of cAMP synthesis in yeast cells. Despite the huge cAMP levels present in these mutants, deletion of the gene (BCY1) coding for the regulatory subunit of cAMP-dependent protein kinase severely reduced hyperaccumulation of cAMP. Glucose-induced hyperaccumulation of cAMP was also observed in exponential-phase glucose-grown cells of the tpklw1 and tpk2w1 strains but not the tpk3w1 strain even though addition of glucose to glucose-repressed wild-type cells did not induce a cAMP signal. Investigation of mitochondrial respiration by in vivo 31P nuclear magnetic resonance spectroscopy showed the tpk1w1 and tpk2w1 strains, to be defective in glucose repression. These results are consistent with the idea that the signal transmission pathway from glucose to adenyl cyclase contains a glucose-repressible protein. They also show that a certain level of cAMP-dependent protein phosphorylation is required for glucose repression. Investigation of the glucose-induced cAMP signal and glucose-induced activation of trehalase in derepressed cells of strains containing only one of the wild-type TPK genes indicates that the transient nature of the cAMP signal is due to feedback inhibition by cAMP-dependent protein kinase.


Assuntos
Glucose/farmacologia , Proteínas Quinases/metabolismo , Saccharomyces cerevisiae/metabolismo , Trifosfato de Adenosina/metabolismo , Ativação Enzimática , Repressão Enzimática , Genótipo , Concentração de Íons de Hidrogênio , Cinética , Proteínas Quinases/biossíntese , Proteínas Quinases/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Transdução de Sinais , Trealase/metabolismo
5.
Int. j interdiscip. dent. (Print) ; 14(2): 152-157, ago. 2021. tab
Artigo em Espanhol | LILACS | ID: biblio-1385205

RESUMO

RESUMEN Objetivo: El objetivo fue definir los contenidos mínimos y sus indicadores de aplicación clínica en el currículo de cariología para las escuelas de odontología chilenas. Metodología: Basados en los 5 dominios curriculares internacionales, se elaboró un documento que define los contenidos e indicadores de aplicación clínica para la enseñanza de cariología en Chile. Posteriormente, profesores de cariología de 20 de 21 escuelas de odontología chilenas (95%), sesionaron para revisar, retroalimentar y elaborar el documento final, denominado "Listado de contenidos mínimos e indicadores de aplicación clínica" en cariología para estudiantes de pregrado de odontología en Chile. Resultados: Se definieron 23 contenidos y 31 indicadores de aplicación clínica para la enseñanza de la cariología. La cantidad de contenidos e indicadores separados por dominio fueron respectivamente: conocimiento de base: 5 y 7; riesgo/detección y diagnóstico: 6 y 6; toma de decisiones/manejo preventivo no operatorio: 5 y 5; decisión de tratamiento operatorio: 4 y 9 y cariología basada en la evidencia: 3 y 4. Conclusiones: Se definieron los contenidos mínimos que tributan a cada dominio y sus indicadores de aplicación clínica para la enseñanza de la cariología en Chile.


ABSTRACT: The objective: was to define the minimum contents and their indicators of clinical application in the cariology curriculum for the Chilean Dental Schools. Methodology: Based on the 5 international curricular domains, a document defining the contents and indicators of clinical application for the teaching of cariology in Chile was elaborated. Later, cariology professors from 20 out of the 21 Chilean Dentistry Schools (95%) met to review, feedback and elaborate the final document, called "List of minimum contents and indicators of clinical application" in cariology for undergraduate dentistry students in Chile. Results: Twenty-three contents and 31 indicators of clinical application for the teaching of cariology were agreed upon. The amount of contents and indicators separated by domain respectively were: basic knowledge: 5 and 7; risk/detection and diagnosis: 6 and 6; decision making/non-operative preventive management: 5 and 5; decision of operative treatment: 4 and 9 and evidence-based cariology: 3 and 4. Conclusions: The minimum contents for each domain and its clinical application indicators for the teaching of cariology in Chile were defined.


Assuntos
Humanos , Faculdades de Odontologia , Cárie Dentária , Educação em Odontologia , Competência Profissional , Chile
6.
Biochim Biophys Acta ; 970(3): 241-50, 1988 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-3401508

RESUMO

Perchloric acid extracts of LLC-PK1/Cl4 cells, a renal epithelial cell line, incubated with either [2-13C]glycine L-[3-13C]alanine, or D,L-[3-13C]aspartic acid were investigated by 13C-NMR spectroscopy. All amino acids, except labelled glycine, gave rise to glycolytic products and tricarboxylic acid cycle (TCA) intermediates. For the first time we also observed activity of gamma-glutamyltransferase activity and glutathione synthetase activity in LLC-PK1 cells, as is evident from enrichment of reduced glutathione. Time courses showed that only 6% of the labelled glycine was utilized in 30 min, whereas 31% of L-alanine and 60% of L-aspartic acid was utilized during the same period. 13C-NMR was also shown to be a useful tool for the determination of amino acid uptake in LLC-PK1 cells. These uptake experiments indicated that glycine, alanine and aspartic acid are transported into Cl4 cells via a sodium-dependent process. From the relative enrichment of the glutamate carbons, we calculated the activity of pyruvate dehydrogenase to be about 61% when labelled L-alanine was the only carbon source for LLC-PK1/Cl4 cells. Experiments with labelled D,L-aspartic, however, showed that about 40% of C-3-enriched oxaloacetate (arising from a de-amination of aspartic acid) reached the pyruvate pool.


Assuntos
Alanina/metabolismo , Ácido Aspártico/metabolismo , Ciclo do Ácido Cítrico , Glicina/metabolismo , Rim/metabolismo , Algoritmos , Animais , Linhagem Celular , Epitélio/metabolismo , Espectroscopia de Ressonância Magnética
7.
Biochim Biophys Acta ; 969(2): 194-7, 1988 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-2833317

RESUMO

In order to characterize intracellular pH regulation and cellular metabolism in PKE 5 cells, a mutant of the renal epithelial cell line LLC-PK1 supposed to lack Na+-H+ exchanger activity, 31P and 13C-NMR studies were conducted. The 31P studies on intact cell suspensions revealed that these cells have an ATP content and an ATP/ADP ratio similar to the parent cell line. Their intracellular pH, in the presence of 5 mM HCO3-, was 7.17 +/- 0.04 (n = 5) - identical to that of LLC-PK1 cells. After acid loading the cells with 15% CO2, the initial rate of realkalinization was 0.027 pH units/min (n = 6), 50% lower than in the parent cells. The recovery rate was not affected by the removal of extracellular sodium or by the addition of 1 mM amiloride. These results indicate that PKE 5 cells are devoid of Na+-H+ exchange activity, but are able to regulate their intracellular pH by amiloride-insensitive, sodium-independent mechanisms. Extracts prepared from PKE 5 cells incubated with [13C]lactate showed 13C spectra identical to those of the parent cell line. In particular, no synthesis of 13C-labeled D-glucose was observed.


Assuntos
Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas de Transporte/metabolismo , Animais , Isótopos de Carbono , Linhagem Celular , Epitélio/metabolismo , Concentração de Íons de Hidrogênio , Rim , Cinética , Espectroscopia de Ressonância Magnética/métodos , Fósforo , Trocadores de Sódio-Hidrogênio
8.
Biochim Biophys Acta ; 971(2): 157-62, 1988 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-2901859

RESUMO

Renal papillary collecting duct cells have been postulated to adapt their intracellular osmolality to the large changes in interstitial osmolality by changing their content of 'non-perturbing' organic osmolytes such as sorbitol and myo-inositol. 13C-NMR was used in this study to elucidate the metabolic pathways leading to a synthesis of those compounds. Incubation of rabbit renal papillary tissue with [1-13C]glucose showed label scrambling mainly into sorbitol (C-1) and lactate (C-3). This result confirms activity of aldose reductase and glycolytic enzymes in renal papillary cells. Using [3-13C]alanine or [2-13C]pyruvate as carbon source, 13C-labeling of sorbitol and myo-inositol was observed, indicating that renal papillary tissue possesses, in addition, gluconeogenic activity. The latter assumption is supported by the result that in enzyme assays rabbit kidney papilla and isolated rat kidney papillary collecting duct cells show significant fructose-1,6-bisphosphatase activity.


Assuntos
Glicerilfosforilcolina/biossíntese , Inositol/biossíntese , Medula Renal/metabolismo , Sorbitol/biossíntese , Alanina/metabolismo , Aldeído Redutase/metabolismo , Animais , Ciclo do Ácido Cítrico , Glucose/metabolismo , Glutamatos/metabolismo , Ácido Glutâmico , Glutamina/metabolismo , Glicólise , Lactatos/metabolismo , Ácido Láctico , Espectroscopia de Ressonância Magnética , Masculino , Concentração Osmolar , Piruvatos/metabolismo , Ácido Pirúvico , Coelhos
9.
Biochim Biophys Acta ; 1136(2): 129-35, 1992 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-1504097

RESUMO

The aim of this study was to investigate the effect of NH4+ on the intracellular pH in TALH SVE.1 cells derived from the medullary thick ascending limb of Henle's loop (TALH) of rabbit kidney. These cells are specialized to perform NH4+ transport in vivo. Intracellular pH was monitored by 31P-NMR. The steady state intracellular pH (pHi) under standard conditions was 7.24 +/- 0.04 (n = 46). Exposure to NH4Cl resulted in an initial intracellular acidification of the TALH SVE.1 cells, followed by a recovery to the initial steady-state pHi value. The NH4(+)-induced acidification followed saturation kinetics up to 20 mM NH4Cl (delta pHmax = 0.2 pHunits). Half-maximal acidification was observed at 0.6 mmol/l. The intracellular acidification due to NH4Cl exposure was completely inhibited by 0.1 mM of the diuretic bumetanide, an inhibitor of the Na+/K+/2Cl- cotransporter. The effect of bumetanide was dose-dependent and a Ki value of 8.10(-7) M was calculated. NH4+ influx via K+ channels or the (Na+ + K+)ATPase could not be detected. pHi recovery to the initial value was caused mainly by amiloride-sensitive Na+/H+ exchange and to a lesser extent by an amiloride-insensitive system, which was not studied in detail. In the presence of bumetanide, pulses of high concentrations of NH4Cl induced small intracellular alkalinizations. From these experiments, an intrinsic buffer capacity (beta i) in TALH SVE.1 cells of 26 +/- 3 mM x pH-1 (pHi = 7.65) was determined. It could also be shown that the TALH SVE.1 cells exhibit maximal 'functional buffer capability' between pHout 6.9 and 7.3. Within these limits the cells can maintain their intracellular pH at a constant level, even though the extracellular pH changes. These data strongly suggest that the Na+/K+/2Cl- cotransporter is the main site of NH4+ entry into rabbit thick ascending limb cells in culture. A high intracellular buffer capacity and potent acid extrusion mechanism cooperate in counteracting the intracellular acidification caused by NH4+ influx into the cell.


Assuntos
Cloreto de Amônio/farmacologia , Rim/metabolismo , Amilorida/farmacologia , Amônia/metabolismo , Animais , Transporte Biológico , Soluções Tampão , Linhagem Celular , Permeabilidade da Membrana Celular , Cloretos/metabolismo , Concentração de Íons de Hidrogênio , Rim/citologia , Rim/efeitos dos fármacos , Cinética , Espectroscopia de Ressonância Magnética , Potássio/metabolismo , Coelhos , Sódio/metabolismo
10.
Biochim Biophys Acta ; 931(3): 326-34, 1987 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-3676349

RESUMO

The regulation of intracellular pH (pHi) in a renal epithelial cell line, LLC-PK1/Cl4, during re-acidification from an alkaline load was studied by 31P-NMR. Intracellular alkalinization was induced by 10 mM ammonium glucuronate or by preloading with and subsequent removal of 20% CO2; the rate of re-acidification was found to be 0.047 pH units/min and 0.053 pH units/min, respectively. This rate of re-acidification was inhibited by 83% if Cl- was removed from the extracellular medium. A similar inhibition was found in the presence of 1 mM 4-acetamido-4'-isothiocyanostilbene-2,2'-disulphonic acid (SITS) (76% inhibition) and 1 mM bumetanide (81% inhibition). No change in recovery was found after removing sodium from the extracellular medium, indicating that LLC-PK1/Cl4 cells recover from an intracellular alkaline load by a Cl-/HCO3- exchanger, which is SITS- and bumetanide-sensitive and has no requirement for sodium. In addition, the steady-state pHi in Cl4 cells was monitored by 31P-NMR. Removal of Cl- from the extracellular medium introduced an increase in pHi by 0.33 pH units, whereas 1 mM SITS and 1 mM bumetanide caused an increase in pHi by 0.14 or 0.13 pH units. In the presence of 1 mM amiloride, an inhibitor of the Na+/H+ exchanger, the steady-state pHi did not change significantly. These results indicate that at pHo 7.4 the steady-state intracellular pH of LLC-PK1/Cl4 cells strongly depends on the activity of the Cl-/HCO3- exchanger. Under the same conditions the activity of the Na+/H+ exchanger seems to be negligible.


Assuntos
Concentração de Íons de Hidrogênio , Túbulos Renais Proximais/citologia , Animais , Bicarbonatos/farmacologia , Linhagem Celular , Cloretos/farmacologia , Células Epiteliais , Espectroscopia de Ressonância Magnética , Suínos
11.
Biochim Biophys Acta ; 1091(2): 179-87, 1991 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-1847303

RESUMO

NMR spectroscopy has been used to characterize a new renal cell line, TALH-SVE.1, which is derived from the medullary thick ascending limb of Henle's loop. From the 31P-NMR spectrum of a suspension of TALH-SVE cells using the chemical shift of the intracellular inorganic phosphate a value of 7.24 +/- 0.04 for the steady-state intracellular pH (pHi) was determined at pHo = 7.40. In addition, the 31P-NMR spectrum indicated rather high levels of UDPG, a finding confirmed by 1H-NMR spectra of perchloric acid extracts. The 1H-NMR data also demonstrate the presence of 'organic osmolytes' such as inositol, sorbitol, choline and glycerophosphoryl choline (GPC). 13C-NMR spectra of perchloric acid extracts of TALH-SVE cells incubated with [2-13C]- and [3-13 C]alanine were used to determine the relative influx in the Krebs cycle via pyruvate carboxylase (PCB) versus the influx via pyruvate dehydrogenase (PDH). The ratio was 0.41, while about 52% of all acetyl-CoA entering the Krebs cycle was unlabeled. 13C-NMR experiments also indicated that TALH-SVE cells lack gluconeogenic activity. The NMR study presented indicates that TALH-SVE cells possess metabolic pathways similar to those of the parental cells.


Assuntos
Ciclo do Ácido Cítrico , Medula Renal/química , Alça do Néfron/química , Alanina/farmacologia , Animais , Linhagem Celular/química , Epitélio/química , Concentração de Íons de Hidrogênio , Alça do Néfron/enzimologia , Alça do Néfron/metabolismo , Espectroscopia de Ressonância Magnética , Modelos Biológicos , Percloratos , Fosfatos , Piruvato Carboxilase/metabolismo , Complexo Piruvato Desidrogenase/metabolismo , Coelhos , Uridina Difosfato Glucose/metabolismo
12.
Biochim Biophys Acta ; 927(2): 203-12, 1987 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-3028491

RESUMO

31P-NMR spectroscopy was used to monitor intracellular pH (pHi) in a suspension of LLC-PK1 cells, a renal epithelial cell line. The regulation of intracellular pH (pHi) was studied during intracellular acidification with 20% CO2 or intracellular alkalinization with 30 mM NH4Cl. The steady-state pHi in bicarbonate-containing Ringer's solution (pHo 7.40) was 7.14 +/- 0.04 and in bicarbonate-free Ringer's solution (pHo 7.40) 7.24 +/- 0.04. When pHo was altered in nominally HCO3(-)-free Ringer's, the intracellular pHi changed to only a small extent between pHo 6.6 and pHo 7.6; beyond this range pHi was linearly related to pHo. Below pHo 6.6 the cell was capable of maintaining a delta pH of 0.2 pH unit (inside more alkaline), above pH 7.6 a delta pH of 0.4 unit could be generated (inside more acid). During exposure to 20% CO2 in HCO3(-)-free Ringer's solution, pHi dropped initially to 6.9 +/- 0.05, the rate of realkalinisation was found to be 0.071 pH unit X min-1. After removal of CO2 the pHi increased by 0.65 and the rate of reacidification was 0.056 pH unit X min-1. Exposure to 30 mM NH4Cl caused a raise of pHi by 0.48 pH unit and an initial rate of re-acidification of 0.063 pH unit X min-1, after removal of NH4Cl the pHi fell by 0.58 pH unit below the steady-state pHi, followed by a subsequent re-alkalinization of 0.083 pH unit X min-1. Under both experimental conditions, the pHi recovery after an intracellular acidification, introduced by exposure to 20% CO2 and by removal of NH4+, was found to be inhibited by 53% and 63%, respectively, in the absence of sodium and 60% and 72%, respectively, by 1 mM amiloride. These studies indicate that 31P-NMR can be used to monitor steady-state intracellular pH as well a pHi transients in suspensions of epithelial cells. The results support the view that LLC-PK1 cells use an Na+-H+ exchange system to readjust their internal pH after acid loading of the cell.


Assuntos
Líquidos Corporais/metabolismo , Líquido Intracelular/metabolismo , Rim/metabolismo , Cloreto de Amônio/farmacologia , Animais , Dióxido de Carbono/farmacologia , Proteínas de Transporte/metabolismo , Linhagem Celular , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Concentração de Íons de Hidrogênio , Soluções Isotônicas/farmacologia , Rim/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Solução de Ringer , Trocadores de Sódio-Hidrogênio , Suínos
13.
Magn Reson Imaging ; 14(10): 1205-15, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9065912

RESUMO

Nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) have been applied to visualize physiological phenomena in plants and agricultural crops. Imaging sequences that result in contrast of a combination of parameters (e.g., proton density, T1, T2, T2*) cannot be used for a correct and unique interpretation of the results. In this study multiecho imaging together with monoexponential T2 decay fitting was applied to determine reliable proton density and T2 distributions over a mushroom. This was done at three magnetic field strengths (9.4, 4.7, and 0.47 T) because susceptibility inhomogeneities were suspected to influence the T2 relaxation times negatively, and because the influences of susceptibility inhomogeneities increase with a rise in magnetic field strength. Electron microscopy was used to understand the different T2's for the various tissue types in mushrooms. Large influences of the tissue ultrastructure on the observed T2 relaxation times were found and explained. Based on the results, it is concluded that imaging mushrooms at low fields (around or below 0.47 T) and short echo times has strong advantages over its high-field counterpart, especially with respect to quantitative imaging of the water balance of mushrooms. These conclusions indicate general validity whenever NMR imaging contrast is influenced by susceptibility inhomogeneities.


Assuntos
Agaricus , Espectroscopia de Ressonância Magnética/métodos , Agaricus/ultraestrutura , Meios de Contraste , Gadolínio , Gadolínio DTPA , Compostos Organometálicos , Ácido Pentético/análogos & derivados
14.
Genet Couns ; 3(3): 139-43, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1388932

RESUMO

We report two sisters with mental retardation, coarse facial features, telecanthus, flat malar region, prominent lower lip, kyphoscoliosis, and tapering fingers. Although these patients' phenotypes showed considerable overlap with the Coffin-Lowry and the Atkin-Flaitz syndromes, their overall picture makes these diagnoses controversial.


Assuntos
Anormalidades Múltiplas/genética , Ossos Faciais/anormalidades , Dedos/anormalidades , Deficiência Intelectual/genética , Fenótipo , Aberrações dos Cromossomos Sexuais/genética , Cromossomo X , Anormalidades Múltiplas/diagnóstico , Adolescente , Diagnóstico Diferencial , Feminino , Genes Dominantes/genética , Humanos , Deficiência Intelectual/diagnóstico , Síndrome
15.
Arch Physiol Biochem ; 118(1): 22-30, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22117101

RESUMO

The perilipin proteins enclose intracellular lipid droplets. We describe the mRNA expression of the five perilipins in human skeletal muscle in relation to fatty acid supply, exercise and energy balance. We observed that all perilipins were expressed in skeletal muscle biopsies with the highest mRNA levels of perilipin 2, 4 and 5. Cultured myotubes predominantly expressed perilipin 2 and 3. In vitro, incubation of myotubes with fatty acids enhanced mRNA expression of perilipin 1, 2 and 4. In vivo, low fat diet increased mRNA levels of perilipin 3 and 4. Endurance training, but not strength training, enhanced the expression of perilipin 2 and 3. Perilipin 1 mRNA correlated positively with body fat mass, whereas none of the perilipins were associated with insulin sensitivity. In conclusion, all perilipins mRNAs were expressed in human skeletal muscle. Diet as well as endurance exercise modulated the expression of perilipins.


Assuntos
Proteínas de Transporte/metabolismo , Ácidos Graxos/farmacologia , Expressão Gênica/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Fosfoproteínas/metabolismo , RNA Mensageiro/biossíntese , Tecido Adiposo , Idoso , Proteínas de Transporte/genética , Técnicas de Cultura de Células , Dieta , Gorduras na Dieta/metabolismo , Metabolismo Energético/fisiologia , Exercício Físico/fisiologia , Feminino , Humanos , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Especificidade de Órgãos , Perilipina-1 , Fosfoproteínas/genética , Resistência Física/fisiologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
19.
Biochem J ; 263(1): 231-41, 1989 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-2604695

RESUMO

13C-n.m.r. spectroscopy was used to determine the metabolic fate of alanine and aspartate in rat and rabbit kidney proximal tubules. The main purpose of the present study was to investigate the effect of streptozotocin-induced diabetes on the influx of 13C label from [3-13C]alanine into the tricarboxylic acid cycle and through the fructose-1,6-bisphosphatase pathway. This influx was calculated from the relative enrichment of 13C in the various glutamate and glutamine carbon atoms. The relative proportion of 13C label which entered the tricarboxylic acid cycle via pyruvate carboxylase relative to the proportion that entered via pyruvate dehydrogenase was 1.92 +/- 0.02 in fed control rats and 2.27 +/- 0.04 in streptozotocin-treated rats. However, streptozotocin-induced diabetes did not significantly affect this ratio in rabbit proximal convoluted tubular cells. Only in rat proximal convoluted tubular cells did we observe an increase in flux through the fructose-1,6-bisphosphatase pathway by streptozotocin treatment compared with fed controls. The data suggest that streptozotocin-induced diabetes in rats causes the same metabolic changes as does chronic acidosis.


Assuntos
Aminoácidos/metabolismo , Diabetes Mellitus Experimental/metabolismo , Túbulos Renais Proximais/metabolismo , Animais , Espectroscopia de Ressonância Magnética , Masculino , Matemática , Coelhos , Ratos , Ratos Endogâmicos
20.
Eur J Biochem ; 174(1): 67-73, 1988 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-3371365

RESUMO

Perchloric acid extracts of rabbit renal proximal convoluted tubular cells (PCT) incubated with [2-13C]glycerol and [1,3-13C]glycerol were investigated by 13C-NMR spectroscopy. These 13C-NMR spectra enabled us to determine cell metabolic pathways of glycerol in PCT cells. The main percentage of 13C-label, arising from 13C-enriched glycerol, was found in glucose, lactate, glutamine and glutamate. So far it can be concluded that glycerol is a suitable substrate for PCT cells and is involved in gluconeogenesis and glycolysis as well in the Krebs cycle intermediates. Label exchange and label enrichment in 13C-labelled glucose, arising from [2-13C]glycerol and [1,3-13C]glycerol, is explained by label scrambling through the pentose shunt and a label exchange in the triose phosphate pool. From relative enrichments it is estimated that the ratio of the pyruvate kinase flux to the gluconeogenetic flux is 0.97:1 and that the ratio of pyruvate carboxylase activity relative to pyruvate dehydrogenase activity is 2.0:1. Our results show that 13C-NMR spectroscopy, using 13C-labelled substrates, is a powerful tool for the examination of renal metabolism.


Assuntos
Glicerol/metabolismo , Túbulos Renais Proximais/metabolismo , Animais , Isótopos de Carbono , Transferência de Energia , Gluconeogênese , Túbulos Renais Proximais/enzimologia , Lactatos/biossíntese , Espectroscopia de Ressonância Magnética , Piruvato Carboxilase/metabolismo , Complexo Piruvato Desidrogenase/metabolismo , Coelhos
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