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1.
Cogent Biol ; 52019.
Artigo em Inglês | MEDLINE | ID: mdl-31440524

RESUMO

Acetaldehyde is a physiological species existing in blood. Glyceraldehyde is a commonly-used surrogate for glucose in studies of nonenzymatic glycation. Both species exist in dynamic equilibrium between two forms, an aldehyde and a hydrate. Nonenzymatic covalent protein modification (NECPM) is a process whereby a protein is covalently modified by a non-glucose species. The purpose here was to elucidate the NECPM mechanism(s) for acetaldehyde and glyceraldehyde with human hemoglobin (HbA). For the first time, both aldehydic and hydrate forms of acetaldehyde and glyceraldehyde were considered. Computations and model reactions followed by 1H NMR were employed. Results demonstrated that the aldehyde and hydrate forms of acetaldehyde bind and covalently-modify Val1 of HbA via different chemical mechanisms, yet generated an identical protonated Schiff base (PSB). The aldehyde and hydrate of glyceraldehyde also covalently-modified Val1 via mechanisms distinct from one another, yet generated an identical PSB. It is noteworthy that the PSB from acetaldehyde and glyceraldehyde were different structures. The PSB from acetaldehyde is proposed to proceed to covalent adducts that have been implicated in alcohol toxicity. Conversely, the PSB generated from glyceraldehyde can form an Amadori which has been implicated in diabetic complications. Thus, the PSB structure generated from acetaldehyde versus glyceraldehyde may be central to pathophysiological outcomes because it determines the structure of the stable covalent adduct formed.

2.
Hemoglobin ; 43(1): 42-49, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31060394

RESUMO

Nonenzymatic glycation (NEG) of human hemoglobin (Hb A) consists of initial non covalent, reversible steps involving glucose and amino acid residues, which may also involve effector reagent(s) in the formation of labile Hb A1c (the conjugate acid of the Schiff base). Labile Hb A1c can then undergo slow, largely irreversible, formation of stable Hb A1c (the Amadori product). Stable Hb A1c is measured to assess diabetic progression after labile Hb A1c removal. This study aimed to increase the understanding of the distinctions between labile and stable Hb A1c from a mechanistic perspective in the presence of 2,3-bisphosphoglycerate (2,3-BPG). 2,3-Bisphosphoglycerate is an effector reagent that reversibly binds in the Hb A1c pocket and modestly enhances overall NEG rate. The deprotonation of C2 on labile Hb A1c in the formation of the Amadori product was previously proposed to be rate-limiting. Computational chemistry was used here to identify the mechanism(s) by which 2,3-BPG facilitates the deprotonation of C2 on labile Hb A1c. 2,3-Bisphosphoglycerate is capable of abstracting protons on C2 and the α-nitrogen of labile Hb A1c and can also deprotonate water and/or amino acid residues, therefore preparing these secondary reagents to deprotonate labile Hb A1c. Parallel reactions not leading to an Amadori product were found that include formation of the neutral Schiff base, dissociation of glucose from the protein, and cyclic glycosylamine formation. These heretofore under appreciated parallel reactions may help explain both the selective removal of labile from stable Hb A1c and the slow rate of NEG.


Assuntos
2,3-Difosfoglicerato/metabolismo , Hemoglobinas Glicadas/metabolismo , 2,3-Difosfoglicerato/química , Aminoácidos/química , Glucose/química , Glucose/metabolismo , Hemoglobinas Glicadas/química , Glicosilação , Humanos , Ligação Proteica , Multimerização Proteica
3.
Cogent Biol ; 42018.
Artigo em Inglês | MEDLINE | ID: mdl-30918913

RESUMO

Nonenzymatic glycation (NEG) begins with the non-covalent binding of a glucopyranose to a protein. The bound glucopyranose must then undergo structural modification to generate a bound electrophile that can reversibly form a Schiff base, which can then lead to Amadori intermediates, and ultimately to glycated proteins. Inorganic phosphate (Pi) is known to accelerate the glycation of human hemoglobin (HbA), although the specific mechanism(s) of Pi as an effector reagent have not been determined. The aim of this study was to determine whether Pi and a glucopyranose can concomitantly bind to HbA and react while bound within the early, noncovalent stages to generate electrophilic species capable of progress in NEG. 31P and 1HNMR of model reactions confirm that bimolecular reactions between Pi and glucopyranose occur generating modified glucose electrophiles. Computations of protein/substrate interactions predict that Pi can concomitantly bind with a glucopyranose in HbA pockets with geometries suitable for multiple acid/base mechanisms that can generate any of four transient electrophiles. Pi-facilitated mechanisms in the noncovalent stages predict that the glycation of ß-Val1 of HbA to HbA1c is a "hot spot" because the ß-Val1 pocket facilitates many more mechanisms than any other site. The mechanistic diversity of the Pi effect within the early noncovalent stages of NEG predicts well the overall site selectivity observed from the in vivo glycation of HbA in the presence of Pi. These insights extend our basic understanding of the NEG process and may have clinical implications for diabetes mellitus and even normal aging.

4.
Diabet Med ; 35(1): 72-77, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29057545

RESUMO

AIM: Glucose-lowering interventions in Type 2 diabetes mellitus have demonstrated reductions in microvascular complications and modest reductions in macrovascular complications. However, the degree to which targeting different HbA1c reductions might reduce risk is unclear. METHODS: Participant-level data for Trial Evaluating Cardiovascular Outcomes with Sitagliptin (TECOS) participants with established cardiovascular disease were used in a Type 2 diabetes-specific simulation model to quantify the likely impact of different HbA1c decrements on complication rates. Ten-year micro- and macrovascular rates were estimated with HbA1c levels fixed at 86, 75, 64, 53 and 42 mmol/mol (10%, 9%, 8%, 7% and 6%) while holding other risk factors constant at their baseline levels. Cumulative relative risk reductions for each outcome were derived for each HbA1c decrement. RESULTS: Of 5717 participants studied, 72.0% were men and 74.2% White European, with a mean (sd) age of 66.2 (7.9) years, systolic blood pressure 134 (16.9) mmHg, LDL-cholesterol 2.3 (0.9) mmol/l, HDL-cholesterol 1.13 (0.3) mmol/l and median Type 2 diabetes duration 9.6 (5.1-15.6) years. Ten-year cumulative relative risk reductions for modelled HbA1c values of 75, 64, 53 and 42 mmol/mol, relative to 86 mmol/mol, were 4.6%, 9.3%, 15.1% and 20.2% for myocardial infarction; 6.0%, 12.8%, 19.6% and 25.8% for stroke; 14.4%, 26.6%, 37.1% and 46.4% for diabetes-related ulcer; 21.5%, 39.0%, 52.3% and 63.1% for amputation; and 13.6%, 25.4%, 36.0% and 44.7 for single-eye blindness. CONCLUSIONS: These simulated complication rates might help inform the degree to which complications might be reduced by targeting particular HbA1c reductions in Type 2 diabetes.


Assuntos
Doenças Cardiovasculares/complicações , Complicações do Diabetes/epidemiologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hemoglobinas Glicadas/metabolismo , Hipoglicemiantes/uso terapêutico , Idoso , Amputação Cirúrgica/estatística & dados numéricos , Cegueira/epidemiologia , Cegueira/etiologia , Complicações do Diabetes/etiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Pé Diabético/epidemiologia , Pé Diabético/etiologia , Retinopatia Diabética/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , Planejamento de Assistência ao Paciente , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia
5.
New Microbes New Infect ; 20: 43-50, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29158908

RESUMO

A cross-sectional serosurvey was performed to identify environmental features or practices of dairy farms associated with risk for exposure to vaccinia-like viruses in dairy cattle in Brazil. Sera from 103 cows from 18 farms in Minas Gerais state were examined for Orthopoxvirus-neutralizing antibodies. A database of 243 binary or multiple-selection categorical variables regarding the physical features and surrounding ecology of each property was obtained. Thirteen of 46 presumptive predictor variables were found to be significantly associated with Orthopoxvirus serostatus by univariate logistic regression methods. Use of teat sanitizer and having felids on the property were independently associated with virus exposure by multivariable analysis. Rodents have long been suspected of serving as maintenance reservoirs for vaccinia-like viruses in Brazil. Therefore, domestic felids are not only effective predators of small rodent pests, but also their urine can serve as a deterrent to rodent habitation in buildings such as stables and barns. These results corroborate previous evidence of the high significance of rodents in the Vaccinia virus transmission cycle, and they also raise questions regarding the common use of teat sanitizers in dairy production areas.

6.
Front Chem ; 5: 39, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28713809

RESUMO

This perspective focuses on illustrating the underappreciated connections between reactive carbonyl species (RCS), initial binding in the nonenzymatic glycation (NEG) process, and nonenzymatic covalent protein modification (here termed NECPM). While glucose is the central species involved in NEG, recent studies indicate that the initially-bound glucose species in the NEG of human hemoglobin (HbA) and human serum albumin (HSA) are non-RCS ring-closed isomers. The ring-opened glucose, an RCS structure that reacts in the NEG process, is most likely generated from previously-bound ring-closed isomers undergoing concerted acid/base reactions while bound to protein. The generation of the glucose RCS can involve concomitantly-bound physiological species (e.g., inorganic phosphate, water, etc.); here termed effector reagents. Extant NEG schemes do not account for these recent findings. In addition, effector reagent reactions with glucose in the serum and erythrocyte cytosol can generate RCS (e.g., glyoxal, glyceraldehyde, etc.). Recent research has shown that these RCS covalently modify proteins in vivo via NECPM mechanisms. A general scheme that reflects both the reagent and mechanistic diversity that can lead to NEG and NECPM is presented here. A perspective that accounts for the relationships between RCS, NEG, and NECPM can facilitate the understanding of site selectivity, may help explain overall glycation rates, and may have implications for the clinical assessment/control of diabetes mellitus. In view of this perspective, concentrations of ribose, fructose, Pi, bicarbonate, counter ions, and the resulting RCS generated within intracellular and extracellular compartments may be of importance and of clinical relevance. Future research is also proposed.

7.
Diabetes Res Clin Pract ; 131: 161-168, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28750219

RESUMO

AIMS: Hypoglycaemia is a significant risk in insulin treated type 2 diabetes and has been associated with future risk of cardiovascular events. We compared the frequency of low-glucose events using continuous glucose monitoring (CGM) with that of self-reported hypoglycemic events at the end of the first and third years of the Treating to Target in Type 2 Diabetes Trial (4-T), which compared biphasic, prandial and basal insulin regimens added to sulfonylurea and metformin. METHODS: CGM using a Medtronic Gold system was performed in a subgroup of 4-T participants. CGM detected low-glucose events were defined at thresholds of ≤3.0 (CGM3.0) and ≤2.2 (CGM2.2) mmol/l. RESULTS: Of the 110 participants, 106 and 70 had CGM analysable data at the end of years 1 and 3 respectively. In both years, the frequency of CGM detected low glucose events was several fold higher than that of self-reported hypoglycaemia (symptoms with blood glucose less than 3.1mmol/l [<56mg/dl]). At the end of the first year, CGM3.0 and CGM2.2 mean (95%CI) event frequencies, expressed at events per participant per year, were 120 (85, 155) and 41 (21, 61) compared with 17 (8, 29) self-reported events during CGM, each p=0.001. The disparity at the end of the third year was similar. CONCLUSIONS: These data demonstrate the likely under-reporting of hypoglycaemia and of potential hypoglycaemia unawareness in clinical trials. The clinical implications of these findings need to be explored further (ISRCTN No ISRCTN51125379).


Assuntos
Automonitorização da Glicemia/métodos , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Hipoglicemia/diagnóstico , Insulina/uso terapêutico , Diabetes Mellitus Tipo 1/sangue , Feminino , Humanos , Hipoglicemia/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade
8.
Diabet Med ; 34(9): 1284-1290, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28477414

RESUMO

AIMS: To evaluate whether plasma glycated albumin, which provides an integrated measure of plasma glucose levels over the preceding 2-4 weeks, better reflects changes in postprandial glucose excursions than HbA1c . METHODS: People with suboptimum glycaemic control on dual oral therapy were enrolled in the Treating-to-Target-in-Type 2 diabetes (4-T) trial, in which participants were randomized to the addition of once-daily basal insulin, twice-daily biphasic insulin or thrice-daily prandial insulin. Glycated albumin levels were assayed enzymatically from baseline and 1-year fasting plasma samples. We evaluated robust correlations of glycated albumin and HbA1c both with fasting and postprandial glucose levels at these two time points, and with insulin-induced changes in the postprandial excursion. RESULTS: Requisite data were available for 625 of the participants in the 4-T trial. Their mean (±sd) age was 62 ± 10 years and body weight was 85.8 ± 15.9 kg, and their median (interquartile range) diabetes duration was 9 (6, 13) years. Partial correlations at baseline and 1 year between postprandial glucose excursions and glycated albumin/HbA1c , after adjusting for fasting glucose, were 0.27/0.15 and 0.22/0.18, respectively. Glycated albumin, compared with HbA1c , explained 66% more of the variation in postprandial glucose excursions at baseline. At 1 year, postprandial glucose excursions on basal, biphasic and prandial and insulin therapy were reduced by 0.43, 0.78 and 1.88 mmol/l, respectively. These reductions were associated with changes in both glycated albumin and HbA1c (P < 0.01), with a stronger association for glycated albumin. CONCLUSION: Changes in glycated albumin and HbA1c reflect changes in postprandial glucose excursions to a similar extent.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Hiperglicemia/sangue , Período Pós-Prandial , Albumina Sérica/fisiologia , Idoso , Biomarcadores/sangue , Insulinas Bifásicas/administração & dosagem , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Esquema de Medicação , Quimioterapia Combinada , Feminino , Hemoglobinas Glicadas/efeitos dos fármacos , Hemoglobinas Glicadas/metabolismo , Produtos Finais de Glicação Avançada , Humanos , Hiperglicemia/diagnóstico , Hiperglicemia/tratamento farmacológico , Insulina Detemir/administração & dosagem , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial/efeitos dos fármacos , Albumina Sérica/metabolismo , Albumina Sérica Glicada
9.
Infection ; 45(5): 669-676, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28349491

RESUMO

There is a paucity of data on the immune reconstitution inflammatory syndrome (IRIS) in the Central African region. We followed ART-naive HIV-infected patients initiating antiretroviral therapy in an HIV clinic in Gabon, for 6 months. Among 101 patients, IRIS was diagnosed in five. All IRIS cases were mucocutaneous manifestations. There were no cases of tuberculosis (TB) IRIS, but active TB (n = 20) was associated with developing other forms of IRIS (p = 0.02). Six patients died. The incidence of IRIS is low in Gabon, with mild, mucocutaneous manifestations.


Assuntos
Antirretrovirais/efeitos adversos , Infecções por HIV/tratamento farmacológico , Síndrome Inflamatória da Reconstituição Imune/epidemiologia , Adulto , Feminino , Gabão/epidemiologia , Humanos , Síndrome Inflamatória da Reconstituição Imune/induzido quimicamente , Síndrome Inflamatória da Reconstituição Imune/etiologia , Síndrome Inflamatória da Reconstituição Imune/imunologia , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tuberculose/complicações
10.
Acta Paediatr ; 105(7): 773-81, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26936312

RESUMO

AIM: Various early intervention programmes have been developed in response to the high rate of neurodevelopmental problems in very preterm infants. We investigated longitudinal effects of the Infant Behavioral Assessment and Intervention Program on cognitive and motor development of very preterm infants at the corrected ages of six months to five and a half years. METHODS: This randomised controlled trial divided 176 infants with a gestational age <32 weeks or birthweight <1500 g into intervention (n = 86) and control (n = 90) groups. Cognitive development and motor development were assessed with the Bayley Scales of Infant Development at the CAs of six, 12 and 24 months and at five and a half years with the Wechsler Preschool and Primary Scale of Intelligence and the Movement Assessment Battery for Children. RESULTS: We found significant longitudinal intervention effects (0.4 SD, p = 0.006) on motor development, but no significant impact on cognitive development (p = 0.063). Infants with bronchopulmonary dysplasia showed significant longitudinal intervention effects for cognitive (0.7 SD; p = 0.019) and motor (0.9 SD; p = 0.026) outcomes. Maternal education had little effect on intervention effects over time. CONCLUSION: The Infant Behavioral Assessment and Intervention Program led to long-term developmental improvements in the intervention group, especially in infants with BPD.


Assuntos
Recém-Nascido Prematuro/crescimento & desenvolvimento , Recém-Nascido de muito Baixo Peso/crescimento & desenvolvimento , Transtornos do Neurodesenvolvimento/prevenção & controle , Displasia Broncopulmonar/complicações , Cognição , Escolaridade , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Destreza Motora , Transtornos do Neurodesenvolvimento/etiologia
11.
Diabet Med ; 33(11): 1569-1574, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26887663

RESUMO

AIMS: To investigate whether metformin therapy alters circulating aromatic and branched-chain amino acid concentrations, increased levels amino acid concentrations, increased levels of which have been found to predict Type 2 diabetes. METHODS: In the Carotid Atherosclerosis: Metformin for Insulin Resistance (CAMERA) study (NCT00723307), 173 individuals without Type 2 diabetes, but with coronary disease, were randomized to metformin (n=86) or placebo (n=87) for 18 months. Plasma samples, taken every 6 months, were analysed using quantitative nuclear magnetic resonance spectroscopy. Ten metabolites consisting of eight amino acids [three branched-chain (isoleucine, leucine, valine), three aromatic (tyrosine, phenylalanine, histidine) and two other amino acids (alanine, glutamine)], lactate and pyruvate were quantified and analysed using repeated-measures models. On-treatment analyses were conducted to investigate whether amino acid changes were dependent on changes in weight, fat mass or insulin resistance estimated using homeostasis model assessment (HOMA-IR). RESULTS: Tyrosine decreased [-6.1 µmol/l (95% CI -8.5, -3.7); P<0.0001], while alanine [42 umol/l (95% CI 25, 59); P<0.0001] increased in the metformin-treated group compared with the placebo-treated group. Decreases in phenylalanine [-2.0 µmol/l (95% CI -3.6, -0.3); P=0.018] and increases in histidine [2.3 µmol/l (95% CI 0.1, 4.6); P=0.045] were also observed in the metformin group, although these changes were less statistically robust. Changes in these four amino acids were not accounted for by changes in weight, fat mass or HOMA-IR values. Levels of branched-chain amino acids, glutamine, pyruvate and lactate were not altered by metformin therapy. CONCLUSIONS: Metformin therapy results in a sustained and specific pattern of changes in aromatic amino acid and alanine concentrations. These changes are independent of any effects on weight and insulin sensitivity. Any causal link to metformin's unexplained cardiometabolic benefit requires further study.


Assuntos
Aminoácidos/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Metformina/uso terapêutico , Adulto , Aminoácidos de Cadeia Ramificada/sangue , Doença das Coronárias/sangue , Doença das Coronárias/tratamento farmacológico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/sangue , Angiopatias Diabéticas/tratamento farmacológico , Método Duplo-Cego , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Placebos
12.
Diabet Med ; 33(2): 224-30, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26043186

RESUMO

AIMS: Reduced aspirin efficacy has been demonstrated in people with Type 2 diabetes. Because increased platelet reactivity and/or turnover are postulated mechanisms, we examined whether higher and/or more frequent aspirin dosing might reduce platelet reactivity more effectively. METHODS: Participants with Type 2 diabetes (n = 24) but without known cardiovascular disease were randomized in a three-way crossover design to 2-week treatment periods with aspirin 100 mg once daily, 200 mg once daily or 100 mg twice daily. The primary outcome was platelet reactivity, assessed using the VerifyNow(™) ASA method. Relationships between platelet reactivity and aspirin dosing were examined using generalized linear mixed models with random subject effects. RESULTS: Platelet reactivity decreased from baseline with all doses of aspirin. Modelled platelet reactivity was more effectively reduced with aspirin 100 mg twice daily vs. 100 mg once daily, but not vs. 200 mg once daily. Aspirin 200 mg once daily did not differ from 100 mg once daily. Aspirin 100 mg twice daily was also more effective than once daily as measured by collagen/epinephrine-stimulated platelet aggregation and urinary thromboxane levels, with a similar trend measured by serum thromboxane levels. No episodes of bleeding occurred. CONCLUSIONS: In Type 2 diabetes, aspirin 100 mg twice daily reduced platelet reactivity more effectively than 100 mg once daily, and numerically more than 200 mg once daily. Clinical outcome trials evaluating primary cardiovascular disease prevention with aspirin in Type 2 diabetes may need to consider using a more frequent dosing schedule.


Assuntos
Aspirina/administração & dosagem , Doenças Cardiovasculares/prevenção & controle , Inibidores de Ciclo-Oxigenase/administração & dosagem , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/prevenção & controle , Cardiomiopatias Diabéticas/prevenção & controle , Inibidores da Agregação Plaquetária/administração & dosagem , Adulto , Aspirina/efeitos adversos , Aspirina/uso terapêutico , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/epidemiologia , Estudos Cross-Over , Inibidores de Ciclo-Oxigenase/efeitos adversos , Inibidores de Ciclo-Oxigenase/uso terapêutico , Diabetes Mellitus Tipo 2/sangue , Angiopatias Diabéticas/epidemiologia , Cardiomiopatias Diabéticas/epidemiologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Resistência a Medicamentos , Inglaterra/epidemiologia , Feminino , Hemorragia/induzido quimicamente , Hemorragia/complicações , Hemorragia/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Agregação Plaquetária/uso terapêutico , Risco , Medição de Risco
13.
Phys Rev Lett ; 114(17): 171301, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25978223

RESUMO

Models such as Natural Inflation that use pseudo-Nambu-Goldstone bosons as the inflaton are attractive for many reasons. However, they typically require trans-Planckian field excursions ΔΦ>MPl, due to the need for an axion decay constant f>MPl to have both a sufficient number of e-folds and values of ns,r consistent with data. Such excursions would in general require the addition of all other higher dimension operators consistent with symmetries, thus disrupting the required flatness of the potential and rendering the theory nonpredictive. We show that in the case of Natural Inflation, the existence of spinodal instabilities (modes with tachyonic masses) can modify the inflaton equations of motion to the point that versions of the model with f

14.
Diabet Med ; 32(8): 1090-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25818859

RESUMO

AIM: To investigate whether previous physical activity levels are associated with blood glucose levels in individuals with impaired glucose tolerance in the context of an international pharmaceutical trial. METHODS: Data were analysed from the NAVIGATOR trial, which involved 9306 individuals with impaired glucose tolerance and high cardiovascular risk from 40 different countries, recruited in the period 2002-2004. Fasting glucose, 2-h post-challenge glucose and physical activity (pedometer) were assessed annually. A longitudinal regression analysis was used to determine whether physical activity levels 2 years (t-2 ) and 1 year (t-1 ) previously were associated with levels of glucose, after adjusting for previous glucose levels and other patient characteristics. Those participants with four consecutive annual measures of glucose and two consecutive measures of physical activity were included in the analysis. RESULTS: The analysis included 3964 individuals. Change in physical activity from t-2 to t-1 and activity levels at t-2 were both associated with 2-h glucose levels after adjustment for previous glucose levels and baseline characteristics; however, the associations were weak: a 100% increase in physical activity was associated with a 0.9% reduction in 2-h glucose levels. In addition, previous physical activity only explained an additional 0.05% of the variance in 2-h glucose over the variance explained by the history of 2-h glucose alone (R(2)  = 0.3473 vs. 0.3468). There was no association with fasting glucose. CONCLUSIONS: In the context of a large international clinical trial, previous physical activity levels did not meaningfully influence glucose levels in those with a high risk of chronic disease, after taking into account participants' previous trajectory of glucose control.


Assuntos
Glicemia/metabolismo , Jejum , Intolerância à Glucose/metabolismo , Atividade Motora , Comportamento de Redução do Risco , Acelerometria , Actigrafia , Idoso , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Doenças Cardiovasculares , Estudos de Coortes , Cicloexanos/uso terapêutico , Feminino , Intolerância à Glucose/tratamento farmacológico , Teste de Tolerância a Glucose , Humanos , Hipoglicemiantes/uso terapêutico , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Nateglinida , Fenilalanina/análogos & derivados , Fenilalanina/uso terapêutico , Estudos Prospectivos , Análise de Regressão , Fatores de Risco , Valsartana/uso terapêutico
15.
Diabetes Obes Metab ; 17(4): 395-402, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25600421

RESUMO

AIMS: To report baseline characteristics and cardiovascular (CV) risk management by region, age, sex and CV event type for 14 724 participants in the Trial Evaluating Cardiovascular Outcomes with Sitagliptin (TECOS), a randomized, double-blind, placebo-controlled trial exploring whether sitagliptin added to usual type 2 diabetes (T2DM) care affects time to first event in the composite endpoint of CV death, non-fatal myocardial infarction (MI), non-fatal stroke or unstable angina hospitalization. METHODS: TECOS enrolled patients aged ≥50 years, with T2DM and CV disease from 38 countries in five regions: North America, Eastern Europe, Western Europe, Asia Pacific and Latin America. Participants had a glycated haemoglobin concentration of 6.5-8.0% (48-64 mmol/mol) and were receiving oral and/or insulin-based antihyperglycaemic therapy. Analysis of variance or logistic regression was used to compare regional CV risk factors and treatments, referenced to North America. RESULTS: Patients had a mean [1 standard deviation (SD)] age of 66 (8) years, a median (interquartile range) diabetes duration of 9.4 (4.9, 15.3) years, and a mean (SD) body mass index 30.2 (5.7) kg/m² . Compared with North America, blood pressure and lipids were higher in all regions. Statin use was lowest in Latin America (68%) and Eastern Europe (70%) and aspirin use was lower compared with North America in all regions except Asia Pacific. Achievement of treatment targets did not differ by age group or insulin usage, but men and participants with previous MI were more likely than women or those with previous stroke or peripheral arterial disease to reach most treatment goals. CONCLUSION: The CV risk factors of participants in TECOS are reasonably controlled, but differences in CV risk management according to region, sex and history of disease exist. This diversity will enhance the generalizability of the trial results.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/tratamento farmacológico , Angiopatias Diabéticas/prevenção & controle , Cardiomiopatias Diabéticas/prevenção & controle , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Fosfato de Sitagliptina/uso terapêutico , Fatores Etários , Idoso , Ásia/epidemiologia , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/terapia , Estudos de Coortes , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/complicações , Angiopatias Diabéticas/epidemiologia , Angiopatias Diabéticas/terapia , Cardiomiopatias Diabéticas/complicações , Cardiomiopatias Diabéticas/epidemiologia , Cardiomiopatias Diabéticas/terapia , Inibidores da Dipeptidil Peptidase IV/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada/efeitos adversos , Europa (Continente)/epidemiologia , Feminino , Hospitalização , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/uso terapêutico , América Latina/epidemiologia , Masculino , Pessoa de Meia-Idade , Mortalidade , América do Norte/epidemiologia , Fatores de Risco , Caracteres Sexuais , Fosfato de Sitagliptina/efeitos adversos
16.
Diabet Med ; 32(4): 459-66, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25439048

RESUMO

AIMS: To estimate the immediate and long-term inpatient and non-inpatient costs for Type 2 diabetes-related complications. METHODS: The costs of all consultations, visits, admissions and procedures associated with diabetes-related complications during UK Prospective Diabetes Study post-trial monitoring in the period 1997-2007 were estimated using hospitalization records for 2791 patients in England and resource use questionnaires that were administered to 3589 patients across the UK. RESULTS: The estimated (95% CI) inpatient care costs (in 2012 pounds sterling) in the event year for the example of a 60-year-old man were: non-fatal ischaemic heart disease £9767 (£7038-£12 696); amputation £9546 (£6416-£13 463); non-fatal stroke £6805 (£3856-£10 278); non-fatal myocardial infarction £6379 (£4290-£8339); fatal stroke £3954 (£2012-£6428); fatal ischaemic heart disease £3766 (£746-£5512); heart failure £3191 (£1678-4903); fatal myocardial infarction £1521 (£647-£2670); and blindness in one eye £1355 (£415-£2655). In subsequent years, estimated (95% CI) costs ranged from £1792 (£1060-£2943) for amputations to £453 (£315-£691) for blindness in one eye. Costs of non-inpatient healthcare in the event year were: amputation £2699 (£1409-£4126); blindness in one eye £1790 (£878-£3056); non-fatal stroke £1019 (£770-£1499); nonfatal myocardial infarction £1963 (£794-£1157); heart failure £979 (£708-£1344); non-fatal ischaemic heart disease £864 (£718-£1014); and cataract extraction £700 (£619-£780). In each subsequent year, non-inpatient costs ranged from £1611 (£1193-£2116) for amputations to £654 (£572-£799) for ischaemic heart disease. CONCLUSIONS: Diabetic complications are associated with substantial immediate and long-term healthcare costs. Our comprehensive new estimates of these costs, derived from detailed recent UK Prospective Diabetes Study post-trial data, should aid researchers and health policy analyses.


Assuntos
Complicações do Diabetes/economia , Diabetes Mellitus Tipo 2/economia , Custos de Cuidados de Saúde/estatística & dados numéricos , Idoso , Diabetes Mellitus Tipo 2/complicações , Feminino , Custos Hospitalares/estatística & dados numéricos , Hospitalização/economia , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reino Unido
17.
Eur J Cancer ; 50(18): 3198-205, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25454415

RESUMO

Myelodysplastic syndromes (MDS) comprise bone marrow failure diseases with a diverse clinical outcome. For improved risk stratification, the International Prognostic Scoring System (IPSS) has recently been revised (IPSS-R). This single-centre study aimed to validate the IPSS-R and to evaluate prior prognostic scoring systems for MDS. We retrospectively analysed 363 patients diagnosed with MDS according to the FAB criteria between 2000 and 2012. The IPSS, MD Anderson Risk Model Score (MDAS), World Health Organisation (WHO)-classification based Prognostic Scoring System (WPSS), refined WPSS (WPSS-R), IPSS-R and MDS-Comorbidity Index (MDS-CI) were applied to 222 patients considered with primary MDS following the WHO criteria and their prognostic power was investigated. According to the IPSS-R, 18 (8%), 81 (37%), 50 (23%), 43 (19%) and 30 (13%) patients were classified as very low, low, intermediate, high and very high risk with, respectively, a median overall survival of 96 (95% Confidence interval (CI) not reached), 49 (95% CI 34-64), 22 (95% CI 0-49), 19 (95% CI 11-27) and 10 (95% CI 6-13) months (p<.000). The IPSS-R showed improved prognostic power as compared to the IPSS, MDAS, WPSS and WPSS-R. Furthermore, the MDS-CI refined the risk stratification of MDS patients stratified according to the IPSS-R. In conclusion, accounting for the disease status by means of the IPSS-R and comorbidity through the MDS-CI considerably improves the prognostic assessment in MDS patients.


Assuntos
Síndromes Mielodisplásicas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Transformação Celular Neoplásica , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/mortalidade , Prognóstico , Estudos Retrospectivos , Medição de Risco , Análise de Sobrevida , Adulto Jovem
18.
Diabetes Obes Metab ; 16(12): 1265-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24861892

RESUMO

Increased physical activity is known to be beneficial in people with type 2 diabetes mellitus (T2DM), but it is not known whether individuals change their activity levels after T2DM diagnosis. The present Nateglinide and Valsartan in Impaired Glucose Tolerance Outcomes Research (NAVIGATOR) trial, conducted in participants with impaired glucose tolerance at high cardiovascular risk, assessed ambulatory activity annually using research-grade pedometers. Oral glucose tolerance tests were performed annually and repeated to confirm T2DM diagnosis. This observational analysis used general linear models to compare step counts before and after T2DM diagnosis in the 2816 participants with the requisite data. Participants were relatively inactive at baseline, taking a median (interquartile range) of 5488 (3258-8361) steps/day, which decreased after T2DM diagnosis by a mean (s.e.) of 258 (64) steps/day (p < 0.0001); however, after adjusting for background trend for activity, step count after T2DM diagnosis was unchanged [mean (s.e.) of 103 (87) fewer steps/day; p = 0.23]. Awareness of T2DM diagnosis had no impact on the trajectory of activity established before the diagnosis.


Assuntos
Actigrafia , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/psicologia , Angiopatias Diabéticas/prevenção & controle , Monitorização Ambulatorial , Atividade Motora , Comportamento de Redução do Risco , Caminhada , Actigrafia/instrumentação , Glicemia/metabolismo , Pressão Sanguínea , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/terapia , Progressão da Doença , Exercício Físico , Feminino , Teste de Tolerância a Glucose , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Ambulatorial/instrumentação , Cooperação do Paciente , Educação de Pacientes como Assunto , Fatores de Risco
19.
Diabet Med ; 31(2): 200-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24267048

RESUMO

AIMS: Evidence of ethnic differences in vascular complications of diabetes has been inconsistent. The aim of this study was to examine the relationship between ethnicity and long-term outcome in a large sample of individuals with newly diagnosed Type 2 diabetes. METHODS: In a prospective observational study of 4273 UK Prospective Diabetes Study participants followed for a median of 18 years, 3543 (83%) were White Caucasian, 312 (7%) Afro-Caribbean and 418 (10%) Asian Indian. Relative risks for predefined outcomes were assessed comparing Afro-Caribbean and Asian Indian with White Caucasian using accelerated failure time models, with adjustment for cardiovascular risk factors and other potentially confounding variables. RESULTS: During follow-up, 2468 (58%) participants had any diabetes-related end point, 1037 (24%) a myocardial infarction and 401 (9%) a stroke, and 1782 (42%) died. Asian Indian were at greater risk (relative risk, 95% confidence interval) for any diabetes-related end point (1.18, 1.07-1.29), but at lower risk of all-cause mortality (0.89, 0.80-0.97) and peripheral vascular disease (0.43, 0.23-0.82), vs. White Caucasian. Afro-Caribbean participants were at lower risk for all-cause mortality (0.84, 0.76-0.93), diabetes-related death (0.75, 0.64-0.88), myocardial infarction (0.55, 0.43-0.71) and peripheral vascular disease (0.55, 0.33-0.93) vs. White Caucasian. No ethnicity-related associations were found for stroke or microangiopathy. CONCLUSIONS: Asian Indian ethnicity is associated with the greatest burden of disease, but not with an increased risk of major vascular complications or death. Afro-Caribbean ethnicity is associated with reduced risk of all-cause and diabetes-related death, myocardial infarction and peripheral vascular disease, suggesting an ethnicity-specific protective mechanism.


Assuntos
Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/etnologia , Etnicidade/estatística & dados numéricos , Adulto , Povo Asiático/estatística & dados numéricos , População Negra/estatística & dados numéricos , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Índia/etnologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Reino Unido/epidemiologia , Índias Ocidentais/etnologia , População Branca/estatística & dados numéricos
20.
Diabetologia ; 56(9): 1925-33, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23793713

RESUMO

AIMS/HYPOTHESIS: The aim of this project was to build a new version of the United Kingdom Prospective Diabetes Study (UKPDS) Outcomes Model (UKPDS-OM1), a patient-level simulation tool for predicting lifetime health outcomes of people with type 2 diabetes mellitus. METHODS: Data from 5,102 UKPDS patients from the 20 year trial and the 4,031 survivors entering the 10 year post-trial monitoring period were used to derive parametric proportional hazards models predicting absolute risk of diabetes complications and death. We re-estimated the seven original event equations and estimated new equations for diabetic ulcer and some second events. The additional data permitted inclusion of new risk factor predictors such as estimated GFR. We also developed four new equations for all-cause mortality. Internal validation of model predictions of cumulative incidence of all events and death was carried out and a contemporary patient-level dataset was used to compare 10 year predictions from the original and the new models. RESULTS: Model equations were based on a median 17.6 years of follow-up and up to 89,760 patient-years of data, providing double the number of events, greater precision and a larger number of significant covariates. The new model, UKPDS-OM2, is internally valid over 25 years and predicts event rates for complications, which are lower than those from the existing model. CONCLUSIONS/INTERPRETATION: The new UKPDS-OM2 has significant advantages over the existing model, as it captures more outcomes, is based on longer follow-up data, and more comprehensively captures the progression of diabetes. Its use will permit detailed and reliable lifetime simulations of key health outcomes in people with type 2 diabetes mellitus.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Avaliação de Resultados em Cuidados de Saúde , Estudos Prospectivos , Reino Unido
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