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1.
Arthritis Res Ther ; 25(1): 131, 2023 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-37501212

RESUMO

INTRODUCTION: Patients with psoriatic arthritis (PsA) are frequently obese. We have previously shown decreased disease activity in patients with PsA with a body mass index (BMI) ≥ 33 kg/m2 following weight loss treatment with Very Low Energy Diet (VLED), resulting in a median weight loss of 18.6% at six months (M6) after baseline (BL). In this study we assessed the effects of VLED on cytokines and adipokines at M6 in the same patients with PsA and controls (matched on sex, age and weight). METHODS: VLED (640 kcal/day) during 12 or 16 weeks, depending on BL BMI < 40 or ≥ 40 kg/m2, was taken and followed by an energy-restricted diet. Cytokines and adipokines were measured with Magnetic Luminex Assays at BL and M6. RESULTS: Serum interleukin (IL)-23, (median (interquartile range) 0.40 (0.17-0.54) ng/mL vs. 0.18 (0.10-0.30) ng/mL, p < 0.001) and leptin (26.28 (14.35-48.73) ng/mL vs. 9.25 (4.40-16.24) ng/mL, p < 0.001) was significantly decreased in patients with PsA. Serum total (tot)-adiponectin and high molecular weight (HMW) adiponectin increased significantly. Similar findings were found in controls. Also, in patients with PsA, ∆BMI was positively correlated with ∆IL-23 (rS = 0.671, p < 0.001). In addition, significant positive correlations were found between ΔBMI and ΔDisease Activity Score (DAS28CRP), ΔCRP, Δtumor necrosis factor (TNF)-α, ΔIL-13, ∆IL-17 and Δleptin, and negative correlations between ΔBMI and Δtot-adiponectin. CONCLUSIONS: Weight loss was associated with decreased levels of leptin and cytokines, in particular IL-23. These findings may partly explain the anti-inflammatory effect of weight reduction in PsA. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02917434, registered on September 21, 2016, retrospectively registered.


Assuntos
Artrite Psoriásica , Leptina , Humanos , Adiponectina , Interleucina-23 , Obesidade/complicações , Obesidade/terapia , Adipocinas , Citocinas , Redução de Peso , Fator de Necrose Tumoral alfa
2.
Nat Commun ; 12(1): 6209, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34707115

RESUMO

Stimulated Brillouin scattering experiments in the ionospheric plasma using a single electromagnetic pump wave have previously been observed to generate an electromagnetic sideband wave, emitted by the plasma, together with an ion- acoustic wave. Here we report results of a controlled, pump and probe beat-wave driven Brillouin scattering experiment, in which an ion-acoustic wave generated by the beating of electromagnetic pump and probe waves, results in electromagnetic sideband waves that are recorded on the ground. The experiment used the EISCAT facility in northern Norway, which has several high power electromagnetic wave transmitters and receivers in the radio frequency range. An electromagnetic pump consisting of large amplitude radio waves with ordinary (O) or extraordinary (X) mode polarization was injected into the overhead ionosphere, along with a less powerful probe wave, and radio sideband emissions observed on the ground clearly show stimulated Brillouin emissions at frequencies agreeing with, and changing with, the pump and probe frequencies. The experiment was simulated using a numerical full-scale model which clearly supports the interpretation of the experimental results. Such controlled beat-wave experiments demonstrate a way of remotely investigating the ionospheric plasma parameters.

3.
Scand J Rheumatol ; 49(3): 195-199, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31631735

RESUMO

Objectives: We aimed to determine the prevalence of cardiovascular risk factors in patients with psoriatic arthritis (PsA) followed at a large Swedish Rheumatology Clinic, and to compare differences in cardiovascular risk factors between men and women with PsA and with the general population.Method: A questionnaire was sent to patients with PsA registered at the Rheumatology Clinic at Sahlgrenska University Hospital, Gothenburg (n = 982). Comparisons with the general population were made using data from the Swedish National Public Health Survey. Descriptive statistics are presented. Body mass index (BMI) was calculated using self-reported height and weight.Results: Overall, 692 (70.6%) of the patients with PsA responded. The mean ± sd age was 55.6 ± 11.4 years and 52% were women. Obesity (BMI ≥ 30 kg/m2) was more prevalent (p < 0.001) in patients with PsA (28.6%) than in matched subjects from the general population (16.3%). Hypertension was also more prevalent (p < 0.001) in PsA (40.3%) than in matched subjects from the general population (24.1%), as was diabetes, with a prevalence of 10.5% in the PsA population compared with 6.2% in matched subjects (p < 0.001).Conclusion: We found obesity to be highly overrepresented in patients with PsA compared with matched subjects from the general population. This difference was particularly seen in women with PsA. Hypertension and ever smoking were also more prevalent in women with PsA compared with matched subjects from the general population.


Assuntos
Artrite Psoriásica/epidemiologia , Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus/epidemiologia , Hipertensão/epidemiologia , Obesidade/epidemiologia , Fumar/epidemiologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Sexuais , Suécia/epidemiologia
4.
Diabetes Res Clin Pract ; 153: 14-22, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31078666

RESUMO

AIMS: To compare the effects of long-term treatment with the GLP-1RA exenatide twice-daily versus titrated insulin glargine (iGlar) on renal function and albuminuria in type 2 diabetes (T2DM) patients. METHODS: We post-hoc evaluated renal outcome-data of 54 overweight T2DM patients (mean  ±â€¯SD age 60 ±â€¯8 years, HbA1c 7.5 ±â€¯0.9%, eGFR 86 ±â€¯16 mL/min/1.73 m2, median [IQR] urinary albumin-to-creatinine-ratio (UACR) 0.75 [0.44-1.29] mg/mmol) randomised to exenatide 10 µg twice-daily or titrated iGlar on-top-of metformin for 52-weeks. Renal efficacy endpoints were change in creatinine clearance (CrCl) and albuminuria (urinary albumin-excretion [UAE] and UACR) based on 24-h urines, collected at baseline and Week-52. eGFR and exploratory endpoints were collected throughout the intervention-period, and after a 4-week wash-out. RESULTS: HbA1c-reductions were similar with exenatide (mean ±â€¯SEM -0.80 ±â€¯0.10%) and iGlar (-0.79 ±â€¯0.14%; treatment-difference 0.02%; 95% CI -0.31 to 0.42%). Change from baseline to Week-52 in CrCl, UAE or UACR did not statistically differ; only iGlar reduced albuminuria (P < 0.05; within-group). eGFR decreased from baseline to Week-4 with exenatide (-3.9 ±â€¯2.1 mL/min/1.73 m2; P = 0.069) and iGlar (-2.7 ±â€¯1.2 mL/min/1.73 m2; P = 0.034), without treatment-differences in ensuing trajectory. Exenatide versus iGlar reduced bodyweight (-5.4 kg; 2.9-7.9; P < 0.001), but did not affect blood pressure, lipids or plasma uric acid. CONCLUSIONS: Among T2DM patients without overt nephropathy, one-year treatment with exenatide twice-daily does not affect renal function-decline or onset/progression of albuminuria compared to titrated iGlar. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT00097500.


Assuntos
Albuminúria/urina , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Exenatida/uso terapêutico , Hipoglicemiantes/uso terapêutico , Insulina Glargina/uso terapêutico , Testes de Função Renal/métodos , Nefropatias Diabéticas/patologia , Exenatida/farmacologia , Feminino , Humanos , Hipoglicemiantes/farmacologia , Insulina Glargina/farmacologia , Masculino , Pessoa de Meia-Idade
5.
J Intern Med ; 282(2): 187-201, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28548281

RESUMO

BACKGROUND: Overconsumption of dietary sugars, fructose in particular, is linked to cardiovascular risk factors such as type 2 diabetes, obesity, dyslipidemia and nonalcoholic fatty liver disease. However, clinical studies have to date not clarified whether these adverse cardiometabolic effects are induced directly by dietary sugars, or whether they are secondary to weight gain. OBJECTIVES: To assess the effects of fructose (75 g day-1 ), served with their habitual diet over 12 weeks, on liver fat content and other cardiometabolic risk factors in a large cohort (n = 71) of abdominally obese men. METHODS: We analysed changes in body composition, dietary intake, an extensive panel of cardiometabolic risk markers, hepatic de novo lipogenesis (DNL), liver fat content and postprandial lipid responses after a standardized oral fat tolerance test (OFTT). RESULTS: Fructose consumption had modest adverse effects on cardiometabolic risk factors. However, fructose consumption significantly increased liver fat content and hepatic DNL and decreased ß-hydroxybutyrate (a measure of ß-oxidation). The individual changes in liver fat were highly variable in subjects matched for the same level of weight change. The increase in liver fat content was significantly more pronounced than the weight gain. The increase in DNL correlated positively with triglyceride area under the curve responses after an OFTT. CONCLUSION: Our data demonstrated adverse effects of moderate fructose consumption for 12 weeks on multiple cardiometabolic risk factors in particular on liver fat content despite only relative low increases in weight and waist circumference. Our study also indicates that there are remarkable individual differences in susceptibility to visceral adiposity/liver fat after real-world daily consumption of fructose-sweetened beverages over 12 weeks.


Assuntos
Bebidas/efeitos adversos , Frutose/efeitos adversos , Metabolismo dos Lipídeos , Fígado/metabolismo , Obesidade Abdominal/complicações , Obesidade Abdominal/metabolismo , Edulcorantes/efeitos adversos , Adulto , Idoso , Composição Corporal , Doenças Cardiovasculares/etiologia , Dieta , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
6.
Nutr Metab Cardiovasc Dis ; 27(6): 534-542, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28428027

RESUMO

BACKGROUND AND AIMS: Incretin hormones glucagon-like peptide (GLP)-1 and glucose-dependent insulinotropic polypeptide (GIP) are affected early on in the pathogenesis of metabolic syndrome and type 2 diabetes. Epidemiologic studies consistently link high fructose consumption to insulin resistance but whether fructose consumption impairs the incretin response remains unknown. METHODS AND RESULTS: As many as 66 obese (BMI 26-40 kg/m2) male subjects consumed fructose-sweetened beverages containing 75 g fructose/day for 12 weeks while continuing their usual lifestyle. Glucose, insulin, GLP-1 and GIP were measured during oral glucose tolerance test (OGTT) and triglycerides (TG), GLP-1, GIP and PYY during a mixed meal test before and after fructose intervention. Fructose intervention did not worsen glucose and insulin responses during OGTT, and GLP-1 and GIP responses during OGTT and fat-rich meal were unchanged. Postprandial TG response increased significantly, p = 0.004, and we observed small but significant increases in weight and liver fat content, but not in visceral or subcutaneous fat depots. However, even the subgroups who gained weight or liver fat during fructose intervention did not worsen their glucose, insulin, GLP-1 or PYY responses. A minor increase in GIP response during OGTT occurred in subjects who gained liver fat (p = 0.049). CONCLUSION: In obese males with features of metabolic syndrome, 12 weeks fructose intervention 75 g/day did not change glucose, insulin, GLP-1 or GIP responses during OGTT or GLP-1, GIP or PYY responses during a mixed meal. Therefore, fructose intake, even accompanied with mild weight gain, increases in liver fat and worsening of postprandial TG profile, does not impair glucose tolerance or gut incretin response to oral glucose or mixed meal challenge.


Assuntos
Bebidas/efeitos adversos , Glicemia/metabolismo , Carboidratos da Dieta/efeitos adversos , Frutose/efeitos adversos , Hormônios Gastrointestinais/sangue , Teste de Tolerância a Glucose , Insulina/sangue , Síndrome Metabólica/sangue , Obesidade/sangue , Adulto , Idoso , Biomarcadores/sangue , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/sangue , Ingestão de Líquidos , Europa (Continente) , Frutose/administração & dosagem , Frutose/sangue , Humanos , Resistência à Insulina , Fígado/metabolismo , Fígado/patologia , Masculino , Síndrome Metabólica/diagnóstico , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade , Obesidade/diagnóstico , Obesidade/fisiopatologia , Período Pós-Prandial , Valor Preditivo dos Testes , Quebeque , Fatores de Tempo , Triglicerídeos/sangue , Aumento de Peso , Adulto Jovem
7.
Diabet Med ; 34(3): 411-418, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27647178

RESUMO

AIMS: To describe factors associated with prevalence or absence of microvascular and macrovascular complications in people with Type 1 diabetes of very long duration and to investigate the risk factors associated with the incidence of such complications. METHODS: We included individuals with Type 1 diabetes who had been entered in the Swedish National Diabetes Register between 2002 and 2004 (n = 18 450). First, risk factor distribution in people with diabetes duration of ≥ 50 years was compared between people with and without complications. Second, the incidence of complications during a 10-year follow-up period was studied in all individuals who had no complications at baseline. RESULTS: Among people with a diabetes duration of ≥ 50 years (n = 1023), 453 (44%) had macrovascular disease, 534 (52%) had microvascular disease and 319 (31%) did not have either of the diagnoses. Factors that differed significantly between people with and without macrovascular disease were gender, age, HbA1c , BMI, LDL cholesterol, HDL cholesterol, triglycerides, systolic blood pressure, albuminuria, antihypertensive medication and lipid-lowering medication. The same factors differed significantly between people with and without microvascular disease, with the exception of gender and HDL cholesterol. During the follow-up period, 6.1% of the study cohort were diagnosed with macrovascular disease and 19.6% with microvascular disease. Incidence of macrovascular disease was significantly associated with HbA1c levels. Hazard ratios decreased with longer diabetes duration. CONCLUSIONS: People with Type 1 diabetes who have survived ≥ 50 years without complications are significantly younger, and have significantly lower HbA1c levels, BMI and triglyceride levels than survivors with complications. HbA1c level is a predictor of macrovascular disease, independently of diabetes duration.


Assuntos
Envelhecimento , Diabetes Mellitus Tipo 1/terapia , Angiopatias Diabéticas/prevenção & controle , Hiperglicemia/prevenção & controle , Adolescente , Adulto , Idoso , Estudos de Coortes , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/fisiopatologia , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/fisiopatologia , Progressão da Doença , Feminino , Seguimentos , Hemoglobinas Glicadas/análise , Humanos , Incidência , Masculino , Microvasos/fisiopatologia , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Sistema de Registros , Fatores de Risco , Suécia/epidemiologia , Adulto Jovem
8.
Diabet Med ; 33(3): 316-23, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26498834

RESUMO

AIM: LDL cholesterol (LDL-C) is considered an important cardiovascular disease (CVD) risk factor. Less is known in Type 1 diabetes. We assessed LDL-C and total cholesterol to HDL cholesterol ratio (TC/HDL-C) as predictors of CVD in Type 1 diabetes. METHODS: The study monitored 30 778 people with Type 1 diabetes, baseline 2003-2006, to 31 December 2011. Cox regression analyses were performed with LDL-C and TC/HDL-C as predictors of fatal/non-fatal CVD. Models were adjusted for traditional CVD risk factors. RESULTS: Hazard ratios (HR) (with 95% CI) per 1 mmol/l increase in LDL-C for CVD were 1.09 (1.01-1.18) in people without lipid-lowering medication and 1.02 (0.95-1.09) in people with lipid-lowering medication (P = 0.02 and 0.65). In people aged 40 years or older having a CVD risk factor, and in people with a history of CVD, HR was 1.07 (0.99-1.16) and 1.02 (0.92-1.13) (P = 0.07 and 0.66). HR per 1 unit increase in TC/HDL-C was 1.12 (1.05-1.20) in people without lipid-lowering medication and 1.08 (1.02-1.15) in people with lipid-lowering medication (P < 0.001 and 0.01). For people aged 40 or older and people with a history of CVD, HR was 1.16 (1.09-1.24) and 1.04 (0.95-1.14) (P < 0.001 and 0.43). Broken down into octiles, LDL-C was not a significant predictor of CVD in any group. Higher octiles of TC/HDL-C were significant predictors for CVD in people without lipid-lowering medication and in those aged 40 years or older. CONCLUSION: In this study of people with Type 1 diabetes in clinical practice, LDL-C was not a good predictor of CVD. We found no support for an LDL-C cut-off point < 2.6 mmol/l. TC/HDL-C seems more reliable as a marker for CVD risk when considering primary prevention.


Assuntos
Biomarcadores/sangue , Doenças Cardiovasculares/etiologia , LDL-Colesterol/sangue , Diabetes Mellitus Tipo 1/sangue , Adolescente , Adulto , Idoso , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Estudos de Coortes , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/epidemiologia , Feminino , Humanos , Hipolipemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Suécia/epidemiologia , Adulto Jovem
9.
Artigo em Inglês | MEDLINE | ID: mdl-25019886

RESUMO

The influence of localized water currents on the nonlinear dynamics and stability of large amplitude, statistically distributed gravity waves is investigated theoretically and numerically by means of an evolution equation for a Wigner function governing the spectrum of waves. It is shown that water waves propagating in the opposite direction of a localized current channel can be trapped in the channel, which can lead to the amplification of the wave intensity. Under certain conditions the wave intensity can be further localized due to a self-focusing (Benjamin-Feir) instability. The localized amplification of the wave intensity may increase the probability of extreme events in the form of freak waves, which have been observed in connection with ocean currents.


Assuntos
Gravitação , Modelos Químicos , Dinâmica não Linear , Reologia/métodos , Movimentos da Água , Água/química , Simulação por Computador
10.
Diabet Med ; 31(8): 954-62, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24750341

RESUMO

AIM: To predict mortality risk and life expectancy for patients with type 2 diabetes after a major diabetes-related complication. METHODS: The study sample, taken from the Swedish National Diabetes Register, consisted of 20 836 people with type 2 diabetes who had their first major complication (myocardial infarction, stroke, heart failure, amputation or renal failure) between January 2001 and December 2007. A Gompertz proportional hazards model was derived which determined significant risk factors associated with mortality and was used to estimate life expectancies. RESULTS: Risk of death changed over time according to type of complication, with myocardial infarction initally having the highest initial risk of death, but after the first month, the risk was higher for heart failure, renal failure and amputation. Other factors that increased the risk of death were male gender (hazard ratio 1.06, 95% CI 1.02-1.12), longer duration of diabetes (hazard ratio 1.07 per 10 years, 95% CI 1.04-1.10), smoking (hazard ratio 1.51, 95% CI 1.40-1.63) and macroalbuminuria (hazard ratio 1.14, 95% CI 1.06-1.22). Low BMI, low systolic blood pressure and low estimated GFR also increased mortality risk. Life expectancy was highest after a stroke, myocardial infarction or heart failure, lower after amputation and lowest after renal failure. Smoking and poor renal function were the risk factors which had the largest impact on reducing life expectancy. CONCLUSIONS: Risk of death and life expectancy differs substantially among the major complications of diabetes, and factors significantly increasing risk included smoking, low estimated GFR and albuminuria.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/mortalidade , Cardiomiopatias Diabéticas/mortalidade , Insuficiência Cardíaca/complicações , Modelos Biológicos , Infarto do Miocárdio/complicações , Acidente Vascular Cerebral/complicações , Idoso , Idoso de 80 Anos ou mais , Amputação Cirúrgica/efeitos adversos , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/mortalidade , Angiopatias Diabéticas/cirurgia , Nefropatias Diabéticas/mortalidade , Feminino , Seguimentos , Insuficiência Cardíaca/mortalidade , Humanos , Expectativa de Vida , Masculino , Mortalidade , Infarto do Miocárdio/mortalidade , Prognóstico , Estudos Prospectivos , Sistema de Registros , Insuficiência Renal/complicações , Insuficiência Renal/mortalidade , Fatores de Risco , Acidente Vascular Cerebral/mortalidade , Suécia/epidemiologia
11.
Eur J Prev Cardiol ; 21(2): 244-51, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24227183

RESUMO

AIMS: To estimate risks of coronary heart disease (CHD), cardiovascular disease (CVD), and total mortality with low or higher levels of physical activity (PA) assessed with questionnaire, in an observational study of patients with type-2 diabetes from the Swedish National Diabetes Register. SUBJECTS AND METHODS: A total of 15,462 patients (60 years), were followed for 5 years from baseline in 2004 until 2009, with 760 CVD events and 427 total mortality events based on 54,344 person-years. RESULTS: Comparing 6963 patients with low baseline PA (never or 1-2 times/week for 30 min) and 8499 patients with higher baseline PA (regular 3 times/week or more), hazard ratios for fatal/nonfatal CHD, fatal/nonfatal CVD, fatal CVD, and total mortality were 1.25 (95% CI 1.05-1.48; p = 0.01), 1.26 (95% CI 1.09-1.45; p = 0.002), 1.69 (95% CI 1.18-2.41; p = 0.004), and 1.48 (95% CI 1.22-1.79; p < 0.001), adjusting for age, sex, diabetes duration, diabetes treatment, and smoking (model 1). Adjusting also for HbA1c, systolic blood pressure, low- and high-density lipoprotein cholesterol, triglycerides, body mass index, and albuminuria (model 2), HRs were 1.19 (95% CI 1.00-1.42; p = 0.049), 1.18 (95% CI 1.02-1.36; p = 0.04), 1.54 (95% CI 1.07-2.22; p = 0.02), and 1.41 (95% CI 1.16-1.72; p < 0.001), respectively. Corresponding results (model 2), comparing 4166 patients having low PA both baseline and at follow up with all other 11,296 patients were 1.68 (95% CI 1.41-2.01), 1.68 (95% CI 1.45-1.96), 2.12 (95% CI 1.48-3.03), and 2.03 (95% CI 1.66-2.48) (all p < 0.001) and compared to 2797 patients with low baseline PA and higher PA at follow up were 2.51 (95% CI 1.87-3.38), 2.54 (95% CI 1.98-3.27), 3.26 (95% CI 1.74-6.10), and 2.91 (95% CI 2.08-4.07) (all p < 0.001). CONCLUSIONS: This large observational study of patients with type-2 diabetes showed considerably increased risks for CVD and mortality with low PA.


Assuntos
Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/mortalidade , Atividade Motora , Idoso , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/fisiopatologia , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Sistema de Registros , Medição de Risco , Fatores de Risco , Inquéritos e Questionários , Suécia/epidemiologia , Fatores de Tempo
12.
Eur J Prev Cardiol ; 21(11): 1420-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23774274

RESUMO

AIMS: We assessed the association between different blood lipid measures and risk of fatal/nonfatal coronary heart disease (CHD), which has been less analysed previously in type 2 diabetes. DESIGN, METHODS: Observational study of 46,786 patients with type 2 diabetes, aged 30-70 years, from the Swedish National Diabetes Register, followed for a mean of 5.8 years until 2009. Baseline and updated mean low-density lipoprotein (LDL)-, high-density lipoprotein (HDL)-, non-HDL-cholesterol, and non-HDL-to-HDL-cholesterol ratio were measured. RESULTS: Hazard ratios (HR) for CHD with quartiles 2-4 of baseline lipid measures, with lowest quartile 1 as reference: 1.03-1.29-1.63 for LDL; 1.23-1.41-1.95 for non-HDL; 1.29-1.39-1.57 for HDL; and 1.31-1.67-2.01 for non-HDL:HDL, all p < 0.001 except for quartile 2 of LDL, when adjusted for clinical characteristics and nonlipid risk factors. A similar picture was seen with updated mean values. Splines with absolute 6-year CHD rates in a Cox model showed decreasing rates only down to around 3 mmol/l for LDL, with linearly decreasing rates to the lowest level of non-HDL:HDL. Non-HDL and HDL were independent additive risk factors for CHD risk. HRs per 1 SD continuous decrease in baseline or updated mean HDL were 1.14-1.17 when fully adjusted as above, and 1.08-1.13 when also adjusted for non-HDL (p < 0.001). HRs were 1.13-1.16 adjusted for LDL, and 1.22-1.26 adjusted for total cholesterol and triglycerides (p < 0.001). Splines showed progressively increasing 6-year CHD rates with lower HDL down to 0.5 mmol/l. CONCLUSIONS: This study suggests that lower levels of non-HDL:HDL are a better risk marker for CHD than LDL-cholesterol below 3 mmol/l.


Assuntos
HDL-Colesterol/sangue , LDL-Colesterol/sangue , Doença das Coronárias/epidemiologia , Diabetes Mellitus Tipo 2/sangue , Adulto , Idoso , Biomarcadores/sangue , Doença das Coronárias/diagnóstico , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Sistema de Registros , Medição de Risco , Fatores de Risco , Suécia/epidemiologia , Fatores de Tempo
13.
Artigo em Inglês | MEDLINE | ID: mdl-23496629

RESUMO

We present a theory for the quantum-electrodynamical (QED) parametric scattering instability of an intense photon pulse in an incoherent radiation background. The pump electromagnetic (EM) wave can decay into a scattered daughter EM wave and an acousticlike wave due to the QED vacuum polarization nonlinearity. By a linear instability analysis we obtain a nonlinear dispersion relation for the growth rate of the scattering instability. The nonlinear QED scattering instability can give rise to the exchange of orbital angular momentum between intense Laguerre-Gaussian mode photon pulses and the two daughter waves, which may be a useful method to detect the highly energetic photon gases existing in the vicinity of rotating dense bodies in the Universe, such as pulsars and magnetars. The observation of the scattered waves may reveal information about the twisted acoustic waves in the incoherent photon gas.


Assuntos
Modelos Químicos , Gases em Plasma/química , Teoria Quântica , Simulação por Computador , Campos Eletromagnéticos , Fótons
14.
Phys Rev E Stat Nonlin Soft Matter Phys ; 86(4 Pt 2): 046402, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23214695

RESUMO

We present a fully nonlinear theory for dust acoustic (DA) shocks and DA solitary pulses in a strongly coupled dusty plasma, which have been recently observed experimentally by Heinrich et al. [Phys. Rev. Lett. 103, 115002 (2009)], Teng et al. [Phys. Rev. Lett. 103, 245005 (2009)], and Bandyopadhyay et al. [Phys. Rev. Lett. 101, 065006 (2008)]. For this purpose, we use a generalized hydrodynamic model for the strongly coupled dust grains, accounting for arbitrary large-amplitude dust number density compressions and potential distributions associated with fully nonlinear nonstationary DA waves. Time-dependent numerical solutions of our nonlinear model compare favorably well with the recent experimental works (mentioned above) that have reported the formation of large-amplitude nonstationary DA shocks and DA solitary pulses in low-temperature dusty plasma discharges.

15.
Phys Rev E Stat Nonlin Soft Matter Phys ; 86(3 Pt 2): 036406, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23031033

RESUMO

The quantum relativistic Buneman instability is investigated theoretically using a collective Klein-Gordon model for the electrons and a cold fluid model for the ions. The growth rate and unstable wave spectrum is investigated in different parameter regimes corresponding to various degrees of relativistic and quantum effects. The results may be important for streaming instabilities involving ion dynamics in very dense plasmas.


Assuntos
Modelos Químicos , Gases em Plasma/química , Teoria Quântica , Simulação por Computador
16.
Phys Rev E Stat Nonlin Soft Matter Phys ; 85(5 Pt 2): 056411, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-23004883

RESUMO

A multistream model for spinless electrons in a relativistic quantum plasma is introduced by means of a suitable fluidlike version of the Klein-Gordon-Maxwell system. The one- and two-stream cases are treated in detail. A new linear instability condition for two-stream quantum plasmas is obtained, generalizing the previously known nonrelativistic results. In both the one- and two-stream cases, steady-state solutions reduce the model to a set of coupled nonlinear ordinary differential equations, which can be numerically solved, yielding a manifold of nonlinear periodic and soliton structures. The validity conditions for the applicability of the model are addressed.

17.
Phys Rev E Stat Nonlin Soft Matter Phys ; 86(1 Pt 2): 016403, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23005546

RESUMO

We investigate stimulated scattering instabilities of coherent circularly polarized electromagnetic (CPEM) waves carrying orbital angular momentum (OAM) in dense quantum plasmas with degenerate electrons and nondegenerate ions. For this purpose, we employ the coupled equations for the CPEM wave vector potential and the driven (by the ponderomotive force of the CPEM waves) equations for the electron and ion plasma oscillations. The electrons are significantly affected by the quantum forces (viz., the quantum statistical pressure, the quantum Bohm potential, as well as the electron exchange and electron correlations due to electron spin), which are included in the framework of the quantum hydrodynamical description of the electrons. Furthermore, our investigation of the stimulated Brillouin instability of coherent CPEM waves uses the generalized ion momentum equation that includes strong ion coupling effects. The nonlinear equations for the coupled CPEM and quantum plasma waves are then analyzed to obtain nonlinear dispersion relations which exhibit stimulated Raman, stimulated Brillouin, and modulational instabilities of CPEM waves carrying OAM. The present results are useful for understanding the origin of scattered light off low-frequency density fluctuations in high-energy density plasmas where quantum effects are eminent.


Assuntos
Campos Eletromagnéticos , Modelos Químicos , Gases em Plasma/química , Reologia/métodos , Espalhamento de Radiação , Simulação por Computador , Movimento (Física)
18.
Phys Rev Lett ; 108(16): 165007, 2012 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-22680730

RESUMO

We report a new attractive force between ions that are shielded by degenerate electrons in quantum plasmas. Specifically, we show that the electric potential around an isolated ion has a hard core negative part that resembles the Lennard-Jones-type potential. Physically, the new electric potential is attributed to the consideration of the quantum statistical pressure and the quantum Bohm potential, as well as the electron exchange and electron correlations due to electron-1/2 spin within the framework of the quantum hydrodynamical description of quantum plasmas. The shape of the attractive potential is determined by the ratio between the Bohr radius and the Wigner-Seitz radius of degenerate electrons. The existence of the hard core negative potential will be responsible for the attraction of ions forming lattices and atoms or molecules, as well as for critical points and phase transitions in quantum plasmas at nanoscales.

19.
Diabetologia ; 55(8): 2109-17, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22566103

RESUMO

AIMS/HYPOTHESIS: The aim of this study was to analyse whether the increased mortality rates observed in insulin-treated patients with type 2 diabetes and coronary artery disease are explained by comorbidities and complications. METHODS: A retrospective analysis of data from two Swedish registries of type 2 diabetic patients (n = 12,515) undergoing coronary angiography between the years 2001 and 2009 was conducted. The association between glucose-lowering treatment and long-term mortality was studied after extensive adjustment for cardiovascular- and diabetes-related confounders. Patients were classified into four groups, according to glucose-lowering treatment: diet alone; oral therapy alone; insulin in combination with oral therapy; and insulin alone. RESULTS: After a mean follow-up time of 4.14 years, absolute mortality rates for patients treated with diet alone, oral therapy alone, insulin in combination with oral therapy and insulin alone were 19.2%, 17.4%, 22.9% and 28.1%, respectively. Compared with diet alone, insulin in combination with oral therapy (HR 1.27; 95% CI 1.12, 1.43) and insulin alone (HR 1.62; 95% CI 1.44, 1.83) were associated with higher mortality rates. After adjustment for baseline differences, insulin in combination with oral glucose-lowering treatment (HR 1.22; 95% CI 1.06, 1.40; p < 0.005) and treatment with insulin only (HR 1.17; 95% CI 1.02, 1.35; p < 0.01) remained independent predictors for long-term mortality. CONCLUSIONS/INTERPRETATION: Type 2 diabetes patients treated with insulin and undergoing coronary angiography have a higher long-term mortality risk after adjustment for measured confounders. Further research is needed to evaluate the optimal glucose-lowering treatment for these high-risk patients.


Assuntos
Angiografia Coronária/estatística & dados numéricos , Doença das Coronárias/mortalidade , Diabetes Mellitus Tipo 2/mortalidade , Angiopatias Diabéticas/mortalidade , Dietoterapia/estatística & dados numéricos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Idoso , Comorbidade , Angiografia Coronária/mortalidade , Doença das Coronárias/etiologia , Doença das Coronárias/terapia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/terapia , Angiopatias Diabéticas/etiologia , Angiopatias Diabéticas/terapia , Feminino , Seguimentos , Humanos , Hipoglicemiantes/efeitos adversos , Insulina/efeitos adversos , Masculino , Estudos Retrospectivos , Análise de Sobrevida , Suécia/epidemiologia , Fatores de Tempo
20.
Diabetes Obes Metab ; 14(8): 717-26, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22364580

RESUMO

AIMS: To analyse clinical characteristics and treatment results in unselected type 2 diabetes mellitus (T2DM) patients, with non-pharmacological treatment as well as the most commonly used pharmacological glucose-lowering treatment regimens, in everyday clinical practice. METHODS: In this population-based cross-sectional study, information was linked from the Swedish National Diabetes Register, Prescribed Drug Register and Patient Register. T2DM patients with non-pharmacological treatment and T2DM patients continuously using the 12 most common pharmacological treatment regimens were included in the study (n = 163121). RESULTS: There were statistically significant differences in clinical characteristics between the groups. Patients with insulin-based treatment regimens had the longest duration of diabetes and more cardiovascular risk factors than the T2DM-population in general. The proportion of patients reaching HbA1c ≤ 7% varied between 70.1% (metformin) and 25.0% [premixed insulin (PMI) + SU) in patients with pharmacological treatment. 84.8% of the patients with non-pharmacological treatment reached target. Compared to patients on metformin, patients on other pharmacological treatments had a lower likelihood, with hazard ratios ranging from 0.58; 95% confidence interval (CI), 0.54-0.63 to 0.97;0.94-0.99, of having HbA1c ≤ 7% (adjusted for covariates). Patients on insulin-based treatments had the lowest likelihood, while non-pharmacological treatment was associated with an increased likelihood of having HbA1c ≤ 7%. CONCLUSION: This nation-wide study shows insufficiently reached treatment goals for haemoglobin A1c (HbA1c) in all treatment groups. Patients on insulin-based treatment regimens had the longest duration of diabetes, more cardiovascular risk factors and the highest proportions of patients not reaching HbA1c target.


Assuntos
Doenças Cardiovasculares/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Angiopatias Diabéticas/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Metformina/uso terapêutico , Idoso , Biomarcadores/sangue , Glicemia/metabolismo , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Angiopatias Diabéticas/sangue , Angiopatias Diabéticas/epidemiologia , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Fatores de Risco , Suécia/epidemiologia , Fatores de Tempo , Resultado do Tratamento
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