Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 18 de 18
Filtrar
1.
Am Heart J ; 179: 175-83, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27595693

RESUMO

DEVOTE was designed to evaluate the cardiovascular safety of insulin degludec (IDeg) vs insulin glargine U100 (IGlar) in patients with T2D at high risk of cardiovascular events. DEVOTE is a phase 3b, multicenter, international, randomized, double-blind, active comparator-controlled trial, designed as an event-driven trial that would continue until 633 positively adjudicated primary events were accrued. The primary end point was the time from randomization to a composite outcome consisting of the first occurrence of cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke. Patients with T2D at high risk of cardiovascular complications were randomized 1:1 to receive either IDeg or IGlar, each added to background therapies. This trial was designed to demonstrate statistical noninferiority of IDeg vs IGlar for the primary end point. DEVOTE enrolled 7,637 patients between October 2013 and November 2014 at 436 sites in 20 countries. Of these, 6,506 patients had prior cardiovascular disease or chronic kidney disease, and the remainder had multiple cardiovascular risk factors. DEVOTE was designed to provide conclusive evidence regarding the cardiovascular safety of IDeg relative to IGlar in a high-risk population of patients with T2D.


Assuntos
Doenças Cardiovasculares/mortalidade , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina Glargina/uso terapêutico , Insulina de Ação Prolongada/uso terapêutico , Idoso , Angina Instável/epidemiologia , Comorbidade , Doença das Coronárias/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/metabolismo , Método Duplo-Cego , Feminino , Hemoglobinas Glicadas/metabolismo , Insuficiência Cardíaca/epidemiologia , Hospitalização/estatística & dados numéricos , Humanos , Hipoglicemia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Modelos de Riscos Proporcionais , Insuficiência Renal Crônica/epidemiologia , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia
2.
Diabetes Care ; 38(11): 2151-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26407587

RESUMO

OBJECTIVE: The aim of this trial was to investigate the impact of nocturnal hypoglycemia on sleep patterns (assessed by polysomnography) and counterregulatory hormones. RESEARCH DESIGN AND METHODS: In this single-blinded, crossover trial, 26 subjects with type 2 diabetes attended two experimental night visits (one normoglycemic and one hypoglycemic) in randomized order. Plasma glucose (PG) levels were controlled by hyperinsulinemic glucose clamping. On the hypoglycemic night, hypoglycemia was induced after reaching sleep stage N2 by turning off glucose infusion until the PG target of 2.7-2.8 mmol/L was reached and maintained for 15 min. Thereafter, subjects were brought back to normoglycemia for the rest of the night. On the normoglycemic night, PG was maintained at 5.0-7.0 mmol/L throughout the night. RESULTS: During the first 4 h of sleep (0-4 h; after reaching sleep stage N2), no difference between experimental nights was observed in the rate of electroencephalography-identified arousals or awakenings, but the rate of awakenings was 27% lower during 4-8 h and 20% lower during 0-8 h on the hypoglycemic night than on the normoglycemic night (both statistically significant). Total sleep time tended to be longer on the hypoglycemic night (observed means 366 vs. 349 min, P nonsignificant). Statistically significantly higher counterregulatory hormonal responses (adrenaline, growth hormone, and cortisol) to hypoglycemia were observed compared with normoglycemia. CONCLUSIONS: Nocturnal hypoglycemia in patients with type 2 diabetes caused a decrease in awakening response in the 4-8-h period following the event. These findings underscore the risks associated with nocturnal hypoglycemia because nocturnal hypoglycemia potentially affects the patient's ability to wake up and respond with an adequate intake of carbohydrates.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Hormônios/sangue , Sono/fisiologia , Adulto , Glicemia/análise , Estudos Cross-Over , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Homeostase , Hormônios/fisiologia , Humanos , Hipoglicemia/sangue , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Polissonografia , Método Simples-Cego
3.
Endocr Pract ; 20(8): 785-91, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24518180

RESUMO

OBJECTIVE: The purpose of the present study was to provide clinical data on the efficacy and safety of insulin degludec (IDeg) 200 U/mL compared with IDeg 100 U/mL in patients with type 2 diabetes mellitus (T2DM) currently treated with basal insulin in combination with oral antidiabetic drugs. METHODS: In this 22-week, treat-to-target trial, eligible adult patients with T2DM were randomized 1:1 to IDeg 200 or IDeg 100 U/mL once daily (OD) (n = 186 and 187, respectively). The starting insulin dose was based on a 1:1 transfer of the total prerandomization basal insulin dose. The primary endpoint was change (%) from baseline in glycosylated hemoglobin A1C (A1C) after 22 weeks of treatment. RESULTS: A total of 373 subjects (mean age 59.8 years, A1C 8.2%, fasting plasma glucose 149.6 mg/dL [8.3 mmol/L], body mass index 33.3 kg/m2) were randomized. A1C reduction with IDeg 200 U/mL was noninferior to that of IDeg 100 U/mL (IDeg 200 U/mL - IDeg 100 U/mL estimated treatment difference: -0.11%, 95% confidence interval (CI): -0.28 to 0.05). Rates of overall confirmed hypoglycemia were low and similar between both formulations (5.17 and 5.66 events/patient-year of exposure [PYE] for IDeg 200 and 100 U/mL, respectively). Similarly, the rates of nocturnal confirmed hypoglycemia were low (1.27 and 1.70 events/PYE for 200 and 100 U/mL). In general, both IDeg formulations were well tolerated (respective rates of adverse events: 4.16 and 3.00 events/PYE for 200 and 100 U/mL). CONCLUSION: The 200 and 100 U/mL formulations of IDeg provide comparable and effective levels of glycemic control with similar, low rates of overall confirmed and nocturnal confirmed hypoglycemia.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina de Ação Prolongada/uso terapêutico , Idoso , Glicemia/análise , Peso Corporal , Diabetes Mellitus Tipo 2/sangue , Feminino , Humanos , Insulina de Ação Prolongada/efeitos adversos , Masculino , Pessoa de Meia-Idade
4.
Biochim Biophys Acta ; 1837(2): 226-31, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24184346

RESUMO

It has been suggested that human mitochondrial variants influence maximal oxygen uptake (VO2max). Whether mitochondrial respiratory capacity per mitochondrion (intrinsic activity) in human skeletal muscle is affected by differences in mitochondrial variants is not known. We recruited 54 males and determined their mitochondrial haplogroup, mitochondrial oxidative phosphorylation capacity (OXPHOS), mitochondrial content (citrate synthase (CS)) and VO2max. Intrinsic mitochondrial function is calculated as mitochondrial OXPHOS capacity divided by mitochondrial content (CS). Haplogroup H showed a 30% higher intrinsic mitochondrial function compared with the other haplo group U. There was no relationship between haplogroups and VO2max. In skeletal muscle from men with mitochondrial haplogroup H, an increased intrinsic mitochondrial function is present.


Assuntos
Haplótipos/genética , Mitocôndrias/metabolismo , Citrato (si)-Sintase/metabolismo , Geografia , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Musculares Esqueléticas/metabolismo , Fosforilação Oxidativa , Permeabilidade
5.
Diabetes ; 61(11): 2711-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22829450

RESUMO

Aging is closely associated with muscle insulin resistance, hyperlipidemia, nonalcoholic fatty liver disease (NAFLD), and type 2 diabetes. We examined the hypothesis that muscle insulin resistance in healthy aging promotes increased hepatic de novo lipogenesis (DNL) and hyperlipidemia by altering the distribution pattern of postprandial energy storage. Healthy, normal weight, sedentary elderly subjects pair-matched to young subjects were given two high-carbohydrate meals followed by ¹³C/¹H magnetic resonance spectroscopy measurements of postprandial changes in muscle and liver glycogen and lipid content, and assessment of DNL using ²H2O. Net muscle glycogen synthesis was reduced by 45% (P < 0.007) in the elderly subjects compared with the young, reflecting severe muscle insulin resistance. Net liver glycogen synthesis was similar between groups (elderly, 143 ± 23 mmol/L vs. young, 138 ± 13 mmol/L; P = NS). Hepatic DNL was more than twofold higher in the elderly than in the young subjects (elderly, 14.5 ± 1.4% vs. young, 6.9 ± 0.7%; P = 0.00015) and was associated with approximately threefold higher postprandial hepatic triglyceride (TG) content (P < 0.005) and increased fasting plasma TGs (elderly, 1.19 ± 0.18 mmol/L vs. young, 0.74 ± 0.11 mmol/L; P = 0.02). These results strongly support the hypothesis that muscle insulin resistance in aging promotes hyperlipidemia and NAFLD by altering the pattern of postprandial carbohydrate storage away from muscle glycogen and into hepatic DNL.


Assuntos
Envelhecimento/metabolismo , Fígado Gorduroso/metabolismo , Hiperlipidemias/metabolismo , Resistência à Insulina , Lipogênese , Fígado/metabolismo , Músculo Esquelético/metabolismo , Adulto , Idoso , Envelhecimento/sangue , Carboidratos da Dieta/efeitos adversos , Carboidratos da Dieta/metabolismo , Fígado Gorduroso/etiologia , Feminino , Glicogênio/metabolismo , Humanos , Hiperlipidemias/etiologia , Masculino , Síndrome Metabólica/fisiopatologia , Hepatopatia Gordurosa não Alcoólica , Período Pós-Prandial , Triglicerídeos/sangue , Triglicerídeos/metabolismo , Adulto Jovem
6.
Proc Natl Acad Sci U S A ; 108(33): 13705-9, 2011 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-21808028

RESUMO

Skeletal muscle insulin resistance has been implicated in the pathogenesis of nonalcoholic fatty liver disease (NAFLD) and atherogenic dyslipidemia associated with the metabolic syndrome by altering the distribution pattern of postprandial energy storage. We conducted a study to examine this hypothesis by reversing muscle insulin resistance with a single bout of exercise and measuring hepatic de novo lipogenesis and hepatic triglyceride synthesis after a carbohydrate-rich meal. We studied 12 healthy, young, lean, insulin resistant individuals in an interventional, randomized cross-over trial. The response to the ingestion of a carbohydrate-rich meal was studied at rest and after one 45-min bout of exercise on an elliptical trainer. Hepatic de novo lipogenesis was assessed by using (2)H(2)O, and changes in glycogen and fat content in liver and muscle were measured by (13)C and (1)H magnetic resonance spectroscopy, respectively. Exercise resulted in a greater than threefold increase in postprandial net muscle glycogen synthesis (P < 0.001), reflecting improved muscle insulin responsiveness, and a ≈40% reduction (P < 0.05) in net hepatic triglyceride synthesis. These changes in whole body energy storage were accompanied by a ≈30% decrease in hepatic de novo lipogenesis (P < 0.01) and were independent of changes in fasting or postprandial plasma glucose and insulin concentrations. These data demonstrate that skeletal muscle insulin resistance is an early therapeutic target for the treatment and prevention of atherogenic dyslipidemia and NAFLD in young insulin resistant individuals who are prone to develop the metabolic syndrome and type 2 diabetes.


Assuntos
Dislipidemias/prevenção & controle , Terapia por Exercício , Fígado Gorduroso/prevenção & controle , Resistência à Insulina/fisiologia , Lipogênese/fisiologia , Fígado/metabolismo , Músculo Esquelético/metabolismo , Adulto , Glicemia , Estudos Cross-Over , Carboidratos da Dieta/administração & dosagem , Humanos , Músculo Esquelético/fisiologia , Hepatopatia Gordurosa não Alcoólica , Período Pós-Prandial , Triglicerídeos/biossíntese , Adulto Jovem
7.
Eur J Endocrinol ; 165(4): 631-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21798960

RESUMO

OBJECTIVE: Polycystic ovarian syndrome (PCOS) is associated with skeletal muscle insulin resistance (IR), which has been linked to decreased mitochondrial function. We measured mitochondrial respiration in lean and obese women with and without PCOS using high-resolution respirometry. METHODS: Hyperinsulinemic-euglycemic clamps (40  mU/min per m(2)) and muscle biopsies were performed on 23 women with PCOS (nine lean (body mass index (BMI) <25 kg/m(2)) and 14 obese (BMI >25 kg/m(2))) and 17 age- and weight-matched controls (six lean and 11 obese). Western blotting and high-resolution respirometry was used to determine mitochondrial function. RESULTS: Insulin sensitivity decreased with PCOS and increasing body weight. Mitochondrial respiration with substrates for complex I and complex I+II were similar in all groups, and PCOS was not associated with a decrease in mitochondrial content as measured by mitochondrial DNA/genomic DNA. We found no correlation between mitochondrial function and indices of insulin sensitivity. CONCLUSIONS: In contrast to previous reports, we found no evidence that skeletal muscle mitochondrial respiration is reduced in skeletal muscle of women with PCOS compared with control subjects. Furthermore, mitochondrial content did not differ between our control and PCOS groups. These results question the causal relationship between reduced mitochondrial function and skeletal muscle IR in PCOS.


Assuntos
Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Síndrome do Ovário Policístico/metabolismo , Absorciometria de Fóton , Adulto , Amenorreia/metabolismo , Composição Corporal/fisiologia , Índice de Massa Corporal , DNA Mitocondrial/biossíntese , DNA Mitocondrial/genética , Transporte de Elétrons/fisiologia , Feminino , Técnica Clamp de Glucose , Teste de Tolerância a Glucose , Homeostase/fisiologia , Humanos , Fibras Musculares Esqueléticas/metabolismo , Obesidade/metabolismo , Oligomenorreia/metabolismo , Consumo de Oxigênio/fisiologia
8.
Dan Med Bull ; 58(4): B4272, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21466770

RESUMO

Reduced skeletal muscle mitochondrial function has been proposed to lead to insulin resistance and type 2 diabetes. It has been known for several years that oxidative capacity of skeletal muscle is reduced in patients with type 2 diabetes compared to weight matched controls. The reduction in oxidative capacity supposedly leads to the accumulation of intramyocellular lipid which inhibits insulin signalling and causes insulin resistance. It is not known whether this reduction in mitochondrial capacity is the cause or the effect of type 2 diabetes. This PhD-thesis describes the effect of different pharmacological interventions on mitochondrial function in type 2 diabetes and describe whether mitochondrial function is uniformly distributed to both upper and lower extremities. Furthermore, a hypothesis on the molecular mechanism for weight gain observed with anthyperglycaemic treatment will be presented.


Assuntos
Diabetes Mellitus Tipo 2/patologia , Mitocôndrias/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/enzimologia , Diabetes Mellitus Tipo 2/metabolismo , Transporte de Elétrons/efeitos dos fármacos , Humanos , Hiperglicemia/enzimologia , Hiperglicemia/metabolismo , Hipoglicemiantes/uso terapêutico , Estilo de Vida , Mitocôndrias/efeitos dos fármacos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/enzimologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/enzimologia , Músculo Esquelético/metabolismo , Obesidade , Estresse Oxidativo/efeitos dos fármacos , Consumo de Oxigênio , Rosiglitazona , Saponinas/uso terapêutico , Tiazolidinedionas/uso terapêutico
9.
Clin Physiol Funct Imaging ; 31(2): 124-31, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21091605

RESUMO

Evidence exists for locomotor muscle impairment in patients with chronic obstructive pulmonary disease (COPD), including fiber type alterations and reduced mitochondrial oxidative capacity. In this study high-resolution respirometry was used to quantify oxygen flux in permeabilized fibres from biopsies of the vastus lateralis muscle in patients with COPD and compared to healthy control subjects. The main findings of this study were that (i) routine state 2 respiration was higher in COPD; (ii) state 3 respiration in the presence of ADP was similar in both groups with substrate supply of electrons to complex I (COPD 38·28 ± 3·58 versus control 42·85 ± 3·10 pmol s(-1) mg tissue(-1) ), but O(2) flux with addition of succinate was lower in COPD patients (COPD 63·72 ± 6·33 versus control 95·73 ± 6·53 pmol s(-1) mg tissue(-1) ); (iii) excess capacity of cytochrome c oxidase in COPD patients was only ~50% that of control subjects. These results indicate that quadriceps muscle mitochondrial function is altered in patients with COPD. The regulatory mechanisms underlying these functional abnormalities remain to be uncovered.


Assuntos
Metabolismo Energético , Mitocôndrias Musculares/metabolismo , Consumo de Oxigênio , Doença Pulmonar Obstrutiva Crônica/metabolismo , Músculo Quadríceps/metabolismo , Difosfato de Adenosina/metabolismo , Idoso , Biópsia , Estudos de Casos e Controles , Respiração Celular , Dinamarca , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Testes de Função Respiratória , Ácido Succínico/metabolismo
10.
Metabolism ; 58(8): 1145-52, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19454354

RESUMO

Reduced oxidative capacity of skeletal muscle has been proposed to lead to accumulation of intramyocellular triglyceride (IMTG) and insulin resistance. We have measured mitochondrial respiration before and after a 10% low-calorie-induced weight loss in young obese women to examine the relationship between mitochondrial function, IMTG, and insulin resistance. Nine obese women (age, 32.3 years [SD, 3.0]; body mass index, 33.4 kg/m(2) [SD, 2.6]) completed a 53-day (SE, 3.8) very low calorie diet (VLCD) of 500 to 600 kcal/d without altering physical activity. The target of the intervention was a 10% weight loss; and measurements of mitochondrial respiration, IMTG, respiratory exchange ratio, citrate synthase activity, mitochondrial DNA copy number, plasma insulin, 2-hour oral glucose tolerance test, and free fatty acids were performed before and after weight loss. Mitochondrial respiration was measured in permeabilized muscle fibers using high-resolution respirometry. Average weight loss was 11.5% (P < .05), but the levels of IMTG remained unchanged. Fasting plasma glucose, plasma insulin homeostasis model assessment of insulin resistance, and insulin sensitivity index (composite) obtained during 2-hour oral glucose tolerance test improved significantly. Mitochondrial respiration per milligram tissue decreased by approximately 25% (P < .05), but citrate synthase activity and mitochondrial DNA copy number remained unchanged. Respiratory exchange ratio decreased from 0.87 (SE, 0.01) to 0.79 (SE, 0.02) (P < .05) as a sign of increased whole-body fat oxidation. Markers of insulin sensitivity improved after the very low calorie diet; but mitochondrial function decreased, and IMTG remained unchanged. Our results do not support a direct relationship between mitochondrial function and insulin resistance in young obese women and do not support a direct relationship between IMTG and insulin sensitivity in young obese women during weight loss.


Assuntos
Restrição Calórica , Respiração Celular , Resistência à Insulina , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Obesidade/metabolismo , Triglicerídeos/metabolismo , Redução de Peso , Adulto , Biomarcadores/metabolismo , Glicemia/metabolismo , Citrato (si)-Sintase/metabolismo , DNA Mitocondrial/metabolismo , Ácidos Graxos não Esterificados/sangue , Feminino , Teste de Tolerância a Glucose , Glicogênio/metabolismo , Humanos , Insulina/sangue , Canais Iônicos/metabolismo , Proteínas Mitocondriais/metabolismo , Músculo Esquelético/fisiopatologia , Obesidade/sangue , Obesidade/enzimologia , Proteína Desacopladora 3
11.
J Clin Endocrinol Metab ; 94(4): 1372-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19141588

RESUMO

AIM: Skeletal muscle mitochondrial content is reduced in type 2 diabetes mellitus (T2DM). Whether hyperglycemia inhibits mitochondrial biogenesis and/or function is unknown. This study examined the effect of different levels of glycemia on skeletal muscle mitochondrial function in patients with T2DM. PATIENTS AND METHODS: Eleven patients with T2DM [9 males, 2 females; age, 52.8 +/- 2.5 yr (mean +/- se); body mass index, 30.2 +/- 1.1 kg/m(2)] in poor glycemic control were treated with insulin aspart and NPH insulin for a median period of 46 d (range, 31-59). Mitochondrial respiration and citrate synthase activity (a marker of mitochondrial content) were measured before and after treatment. Eleven healthy subjects (age, 53.3 +/- 2.7 yr; body mass index, 30.6 +/- 1.1 kg/m(2)) were included as controls. RESULTS: Hemoglobin A1c (9.1 +/- 0.5 to 7.5 +/- 0.3%; P < 0.001) and fasting plasma glucose (12.7 +/- 1.1 to 6.5 +/- 0.3 mmol/liter; P < 0.001) were reduced after treatment. Mitochondrial respiration per milligram muscle was lower in T2DM compared to controls [substrates for complex I, 24% lower (P < 0.05); substrates for complex I+II, 17% lower (P < 0.05)]. Mitochondrial respiration and citrate synthase activity did not differ before and after improvements in glycemic control, but mitochondrial respiration correlated with fasting plasma glucose before (r(2) = 0.53; P < 0.05) but not after treatment [r(2) = 0.0024; not significant (NS)]. Mitochondrial respiration normalized to mitochondrial content did not differ between control subjects and patients with T2DM. DISCUSSION: Mitochondrial respiration and content was not improved after significant improvements in glycemic control. However, severe hyperglycemia inhibited respiration reversibly, but moderate hyperglycemia and mitochondrial function were not correlated.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Hiperglicemia/metabolismo , Mitocôndrias Musculares/metabolismo , Consumo de Oxigênio/fisiologia , Adulto , Idoso , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Frutosamina/sangue , Hemoglobinas Glicadas/efeitos dos fármacos , Hemoglobinas Glicadas/metabolismo , Humanos , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina/análogos & derivados , Insulina/uso terapêutico , Insulina Aspart , Insulina Isófana/uso terapêutico , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Consumo de Oxigênio/efeitos dos fármacos
12.
Aging Cell ; 6(2): 245-56, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17376148

RESUMO

According to the free radical theory of aging, reactive oxygen species (ROS) act as a driving force of the aging process, and it is generally believed that mitochondrial dysfunction is a major source of increased oxidative stress in tissues with high content of mitochondria, such as muscle or brain. However, recent experiments in mouse models of premature aging have questioned the role of mitochondrial ROS production in premature aging. To address the role of mitochondrial impairment and ROS production for aging in human muscles, we have analyzed mitochondrial properties in muscle fibres isolated from the vastus lateralis of young and elderly donors. Mitochondrial respiratory functions were addressed by high-resolution respirometry, and ROS production was analyzed by in situ staining with the redox-sensitive dye dihydroethidium. We found that aged human skeletal muscles contain fully functional mitochondria and that the level of ROS production is higher in young compared to aged muscle. Accordingly, we could not find any increase in oxidative modification of proteins in muscle from elderly donors. However, the accumulation of lipofuscin was identified as a robust marker of human muscle aging. The data support a model, where ROS-induced molecular damage is continuously removed, preventing the accumulation of dysfunctional mitochondria despite ongoing ROS production.


Assuntos
Envelhecimento/fisiologia , Lipofuscina/metabolismo , Mitocôndrias/fisiologia , Músculo Esquelético/metabolismo , Estresse Oxidativo/fisiologia , Adulto , Idoso , Biópsia , Respiração Celular , Feminino , Humanos , Masculino , Consumo de Oxigênio , Espécies Reativas de Oxigênio/metabolismo
13.
Ugeskr Laeger ; 168(13): 1307-10, 2006 Mar 27.
Artigo em Dinamarquês | MEDLINE | ID: mdl-16579882

RESUMO

INTRODUCTION: A survey was conducted to evaluate the level of disagreement between the drug records of family doctors and information provided by patients at the time of hospitalisation. MATERIALS AND METHODS: One hundred patients acutely admitted to a hospital department of medicine were consecutively included if the patient ingested more than two non-OTC drugs. A second drug interview was performed shortly after admission, and the patient's current medication was recorded. If no written medical record from the referring family doctor was available at the time of admission, the doctor was contacted by phone for supplementary information. Discrepancies between the information given by the patient and the medical records of family doctors were recorded. The results were analysed blindly by two of the authors (one senior and one junior doctor) to determine if the discrepancies were clinically relevant for the patient. RESULTS: We found at least one clinically relevant and potentially dangerous discrepancy in the medical records of 40% (95% CI 30%-50%) of the patients. In all, discrepancies were found in the drug lists of 63% of the patients. The patients with discrepancies were similar in age, sex, way of hospitalization and number of drugs ingested, compared to those without discrepancies. Afterwards the family doctors were invited to a meeting in which these problems were evaluated. CONCLUSION: We conclude that there is an urgent need for improvement in the communication between the primary and secondary health care sectors concerning medication being prescribed for patients with chronic diseases. The large number of discrepancies in the drug records of patients in this study is discouraging.


Assuntos
Prescrições de Medicamentos , Prontuários Médicos , Admissão do Paciente , Cooperação do Paciente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Dinamarca , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Medicina de Família e Comunidade , Feminino , Humanos , Comunicação Interdisciplinar , Entrevistas como Assunto , Masculino , Registro Médico Coordenado , Prontuários Médicos/normas , Pessoa de Meia-Idade , Preparações Farmacêuticas/administração & dosagem , Médicos de Família , Estudos Prospectivos
14.
Ugeskr Laeger ; 168(5): 488-9, 2006 Jan 30.
Artigo em Dinamarquês | MEDLINE | ID: mdl-16472442

RESUMO

A 53-year-old non-diabetic man was admitted with hypoglycaemia, neuroglycopenic symptoms and acromegaloid facial swelling. Serum insulin concentration was suppressed, but the free concentration of insulin-like growth factor (IGF-II) was markedly elevated. CT scan demonstrated a large tumour in the liver. The histology showed a benign, solid, fibrous tumour. A hemihepatectomy was performed, and a 3.6 kg tumour was removed. Postoperatively, the blood glucose concentration and the concentration of free IGF-II returned to normal and the acromegaloid facial features disappeared.


Assuntos
Fibroma/complicações , Hipoglicemia/etiologia , Neoplasias Hepáticas/complicações , Diagnóstico Diferencial , Fibroma/diagnóstico , Fibroma/cirurgia , Hepatectomia , Humanos , Hipoglicemia/diagnóstico , Fator de Crescimento Insulin-Like II/análise , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade
15.
Appl Physiol Nutr Metab ; 31(6): 675-83, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17213881

RESUMO

The cause of insulin resistance and type 2 diabetes is unknown. The major part of insulin-mediated glucose disposal takes place in the skeletal muscle, and increased amounts of intramyocellular lipid has been associated with insulin resistance and linked to decreased activity of mitochondrial oxidative phosphorylation. This review will cover the present knowledge and literature on the topics of the activity of oxidative enzymes and the electron transport chain (ETC) in skeletal muscle of patients with type 2 diabetes. Different methods of studying mitochondrial function are described, including biochemical measurements of oxidative enzyme and electron transport activity, isolation of mitochondria for measurements of respiration, and ATP production and indirect measurements of ATP production using nuclear magnetic resonance (NMR) - spectroscopy. Biochemical markers of mitochondrial content are also discussed. Several studies show reduced activity of oxidative enzymes in skeletal muscle of type 2 diabetics. The reductions are independent of muscle fiber type, and are accompanied by visual evidence of damaged mitochondria. In most studies, the reduced oxidative enzyme activity is explained by decreases in mitochondrial content; thus, evidence of a functional impairment in mitochondria in type 2 diabetes is not convincing. These impairments in oxidative function and mitochondrial morphology could reflect the sedentary lifestyle of the diabetic subjects, and the influence of physical activity on oxidative activity and mitochondrial function is discussed. The studies on insulin-resistant offspring of type 2 diabetic parents have provided important insights in the earliest metabolic defects in type 2 diabetes. These defects include reductions in basal ATP production and an attenuated response to insulin stimulation. The decreased basal ATP production does not affect overall lipid or glucose oxidation, and no studies linking changes in oxidative activity and insulin sensitivity in type 2 diabetes have been published. It is concluded that evidence of a functional impairment in mitochondria in type 2 diabetes is not convincing, and that intervention studies describing the correlation between changes in insulin resistance and mitochondrial function in type 2 diabetes are lacking. Specific effects of regular physical training and muscular work on mitochondrial function and plasticity in type 2 diabetes remain an important area of research.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Resistência à Insulina , Mitocôndrias Musculares/metabolismo , Fosforilação Oxidativa , Feminino , Humanos , Masculino
17.
Ugeskr Laeger ; 165(15): 1565-8, 2003 Apr 07.
Artigo em Dinamarquês | MEDLINE | ID: mdl-12715661

RESUMO

INTRODUCTION: The aim of the study was to compute the daily cost of drugs for patients admitted to internal medicine wards and to determine the impact of hospitalization on these costs. Secondly, the aim was to estimate the potential savings on ward drug expenses if the drug prescription was done in accordance with hospital recommendations. MATERIAL AND METHODS: A total of 113 patients from two general internal medicine wards were included consecutively. Drug information was obtained from the case records and through post-discharge telephone interviews. RESULTS: The patients' daily drug costs increased from admission to discharge by DKK 11.95 (95% CI: DKK 5.41-18.49), p = 0.0004. When prescriptions with explicitly determined end dates were excluded, no increment was observed. Post discharge interviews (n = 51) revealed that patients' daily drug costs were similar to the level at admission. The average ward drug expenses per admission were DKK 302.72 (95% CI: DKK 209.07-396.37). A total of 31% and 28% of the prescriptions could have been replaced by drugs in accordance with the hospital drug policy. The average potential amount which could be saved by using a consistent generic prescription was DDK 8.66 (95% CI: DKK 4.61-12.72) per admission. CONCLUSION: The patients' daily drug costs increased significantly from admission to discharge, but the cost increment did not exist one month after discharge. Although roughly one third of the prescriptions could have been substituted, the potential percentage saved only amounted to 2.9.


Assuntos
Custos de Medicamentos , Custos Hospitalares , Departamentos Hospitalares/economia , Medicina Interna/economia , Adulto , Idoso , Redução de Custos , Dinamarca , Uso de Medicamentos/economia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Política Organizacional , Admissão do Paciente , Alta do Paciente , Serviço de Farmácia Hospitalar/economia , Padrões de Prática Médica/economia , Inquéritos e Questionários
18.
Ugeskr Laeger ; 164(19): 2509-13, 2002 May 06.
Artigo em Dinamarquês | MEDLINE | ID: mdl-12025709

RESUMO

INTRODUCTION: A survey was conducted to estimate the benefits of giving supplementary written drug information to the hospitalised patient. The impact on patient knowledge, satisfaction, and attitude towards taking medicine was examined, as was the patients' evaluation of the information material. MATERIAL AND METHODS: The study was carried out in a prospective, non-blind, controlled design. Seventy-eight patients took part in the survey: 35 in the intervention group and 43 in the control group. They were entered consecutively from four different sections of a medical ward, one of which served as the study section and the three others as the control group. The study period ran from November 1999 to July 2000. The patients in the study group were given supplementary drug information in writing. RESULTS: Patients in the study group knew more about the side effects of their drugs than did the patients in the control group. We did not record any differences between the two groups in the number of drug names remembered or knowledge of indications for the prescribed drugs. The number of newly prescribed drugs that, even after a reminder, remained completely unknown to the patient was lower in the study group (30%) than in the control group (55%). Overall, the patients' knowledge about their drugs seems small. Less than half the patients knew the indication for treatment of most (3/4) of their drugs. DISCUSSION: This survey shows that patients' knowledge about their drugs is inadequate. Simple, written information can improve this.


Assuntos
Serviços de Informação sobre Medicamentos , Conhecimentos, Atitudes e Prática em Saúde , Educação de Pacientes como Assunto , Satisfação do Paciente , Autoadministração , Adulto , Idoso , Estudos de Coortes , Dinamarca , Prescrições de Medicamentos , Feminino , Humanos , Pacientes Internados/psicologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...