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1.
J Chem Phys ; 160(9)2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38426527

RESUMEN

A time-dependent vibrational electronic coupled-cluster (VECC) approach is proposed to simulate photo-electron/UV-VIS absorption spectra as well as time-dependent properties for non-adiabatic vibronic models, going beyond the Born-Oppenheimer approximation. A detailed derivation of the equations of motion and a motivation for the ansatz are presented. The VECC method employs second-quantized bosonic construction operators and a mixed linear and exponential ansatz to form a compact representation of the time-dependent wave-function. Importantly, the method does not require a basis set, has only a few user-defined inputs, and has a classical (polynomial) scaling with respect to the number of degrees of freedom (of the vibronic model), resulting in a favorable computational cost. In benchmark applications to small models and molecules, the VECC method provides accurate results compared to multi-configurational time-dependent Hartree calculations when predicting short-time dynamical properties (i.e., photo-electron/UV-VIS absorption spectra) for non-adiabatic vibronic models. To illustrate the capabilities, the VECC method is also successfully applied to a large vibronic model for hexahelicene with 14 electronic states and 63 normal modes, developed in the group by Aranda and Santoro [J. Chem. Theory Comput. 17, 1691, (2021)].

2.
Anal Bioanal Chem ; 414(10): 3279-3289, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35260937

RESUMEN

Early detection of CKD using point of care creatinine and eGFR testing improves patient management outcomes. We undertook a field study to evaluate the use of a whole blood creatinine/eGFR device to screen a rural Nicaraguan population to determine the variability between creatinine methods and specimen types. All specimens including capillary and venous dried blood spots (DBS) were tested with an isotope dilution liquid chromatography mass spectrometry (ID-LCMS) gold standard method. This is to our knowledge the first time a capillary whole blood (POC) method has been directly compared to the gold standard IDMS method, through the novel approach of using dried blood spots. Capillary and venous whole blood specimens were obtained and tested directly with the BCMS method, and then, DBS samples were prepared. Venous plasma specimens were tested using three laboratory analyzer creatinine methods. DBS were sent to the site performing ID-LCMS. Control samples were also prepared to assess the stability of shipment and storage of DBS. The ID-LCMS method was aligned using primary and secondary standards. Sixty-six (66) patients participated in the study, and the CKD prevalence rate was 7.8%. While all creatinine methods showed a good correlation to ID-LCMS, there was a positive bias (mean absolute bias range: 0.21-0.63 mg/dL). All methods used were 100% sensitive, but specificity varied from 62.7 to 94.9% with PPV ranging from 25 to 62.5%. A correction factor was used to align the values from each method to ID-LCMS which improved the specificity of each method. This study used a unique DBS approach to align capillary whole blood creatinine to ID-LCMS. To ensure reliability of BCMS for identifying screened patients with CKD, it is important to establish IDMS traceability and alignment prior to undertaking CKD studies.


Asunto(s)
Insuficiencia Renal Crónica , Cromatografía Liquida/métodos , Creatinina , Pruebas con Sangre Seca/métodos , Humanos , Estándares de Referencia , Insuficiencia Renal Crónica/diagnóstico , Reproducibilidad de los Resultados
3.
Pediatr Diabetes ; 21(7): 1322-1332, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32783254

RESUMEN

OBJECTIVES: To identify biomarkers of renal disease in adolescents with type 1 diabetes (T1D) and to compare findings in adults with T1D. METHODS: Twenty-five serum biomarkers were measured, using a Luminex platform, in 553 adolescents (median [interquartile range] age: 13.9 [12.6, 15.2] years), recruited to the Adolescent Type 1 Diabetes Cardio-Renal Intervention Trial. Associations with baseline and final estimated glomerular filtration rate (eGFR), rapid decliner and rapid increaser phenotypes (eGFR slopes <-3 and > 3 mL/min/1.73m2 /year, respectively), and albumin-creatinine ratio (ACR) were assessed. Results were also compared with those obtained in 859 adults (age: 55.5 [46.1, 64.4) years) from the Scottish Diabetes Research Network Type 1 Bioresource. RESULTS: In the adolescent cohort, baseline eGFR was negatively associated with trefoil factor-3, cystatin C, and beta-2 microglobulin (B2M) (B coefficient[95%CI]: -0.19 [-0.27, -0.12], P = 7.0 × 10-7 ; -0.18 [-0.26, -0.11], P = 5.1 × 10-6 ; -0.12 [-0.20, -0.05], P = 1.6 × 10-3 ), in addition to clinical covariates. Final eGFR was negatively associated with osteopontin (-0.21 [-0.28, -0.14], P = 2.3 × 10-8 ) and cystatin C (-0.16 [-0.22, -0.09], P = 1.6 × 10-6 ). Rapid decliner phenotype was associated with osteopontin (OR: 1.83 [1.42, 2.41], P = 7.3 × 10-6 ), whereas rapid increaser phenotype was associated with fibroblast growth factor-23 (FGF-23) (1.59 [1.23, 2.04], P = 2.6 × 10-4 ). ACR was not associated with any of the biomarkers. In the adult cohort similar associations with eGFR were found; however, several additional biomarkers were associated with eGFR and ACR. CONCLUSIONS: In this young population with T1D and high rates of hyperfiltration, osteopontin was the most consistent biomarker associated with prospective changes in eGFR. FGF-23 was associated with eGFR increases, whereas trefoil factor-3, cystatin C, and B2M were associated with baseline eGFR.


Asunto(s)
Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/complicaciones , Nefropatías Diabéticas/sangre , Nefropatías Diabéticas/etiología , Adolescente , Adulto , Factores de Edad , Biomarcadores/sangre , Niño , Estudios de Cohortes , Cistatina C/sangre , Nefropatías Diabéticas/diagnóstico , Factor-23 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos/sangre , Tasa de Filtración Glomerular , Humanos , Persona de Mediana Edad , Osteopontina/sangre , Factor Trefoil-3/sangre , Adulto Joven , Microglobulina beta-2/sangre
4.
J Chem Phys ; 148(19): 194110, 2018 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-30307181

RESUMEN

We introduce a new path integral Monte Carlo method for investigating nonadiabatic systems in thermal equilibrium and demonstrate an approach to reducing stochastic error. We derive a general path integral expression for the partition function in a product basis of continuous nuclear and discrete electronic degrees of freedom without the use of any mapping schemes. We separate our Hamiltonian into a harmonic portion and a coupling portion; the partition function can then be calculated as the product of a Monte Carlo estimator (of the coupling contribution to the partition function) and a normalization factor (that is evaluated analytically). A Gaussian mixture model is used to evaluate the Monte Carlo estimator in a computationally efficient manner. Using two model systems, we demonstrate our approach to reduce the stochastic error associated with the Monte Carlo estimator. We show that the selection of the harmonic oscillators comprising the sampling distribution directly affects the efficiency of the method. Our results demonstrate that our path integral Monte Carlo method's deviation from exact Trotter calculations is dominated by the choice of the sampling distribution. By improving the sampling distribution, we can drastically reduce the stochastic error leading to lower computational cost.

5.
Am J Respir Crit Care Med ; 196(7): 892-900, 2017 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-28594570

RESUMEN

RATIONALE: Obstructive sleep apnea (OSA) is associated with several pathophysiological deficits found in diabetic retinopathy (DR). Hence, it's plausible that OSA could play a role in the pathogenesis of sight-threatening DR (STDR). OBJECTIVES: To assess the relationship between OSA and DR in patients with type 2 diabetes and to assess whether OSA is associated with its progression. METHODS: A longitudinal study was conducted in diabetes clinics within two U.K. hospitals. Patients known to have any respiratory disorder (including OSA) were excluded. DR was assessed using two-field 45-degree retinal images for each eye. OSA was assessed using a home-based multichannel cardiorespiratory device. MEASUREMENTS AND MAIN RESULTS: A total of 230 patients were included. STDR and OSA prevalence rates were 36.1% and 63.9%, respectively. STDR prevalence was higher in patients with OSA than in those without OSA (42.9% vs. 24.1%; P = 0.004). After adjustment for confounders, OSA remained independently associated with STDR (odds ratio, 2.3; 95% confidence interval, 1.1-4.9; P = 0.04). After a median (interquartile range) follow-up of 43.0 (37.0-51.0) months, patients with OSA were more likely than patients without OSA to develop preproliferative/proliferative DR (18.4% vs. 6.1%; P = 0.02). After adjustment for confounders, OSA remained an independent predictor of progression to preproliferative/proliferative DR (odds ratio, 5.2; 95% CI confidence interval, 1.2-23.0; P = 0.03). Patients who received continuous positive airway pressure treatment were significantly less likely to develop preproliferative/proliferative DR. CONCLUSIONS: OSA is associated with STDR in patients with type 2 diabetes. OSA is an independent predictor for the progression to preproliferative/proliferative DR. Continuous positive airway pressure treatment was associated with reduction in preproliferative/proliferative DR. Interventional studies are needed to assess the impact of OSA treatment on STDR.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Retinopatía Diabética/complicaciones , Apnea Obstructiva del Sueño/complicaciones , Estudios Transversales , Diabetes Mellitus Tipo 2/fisiopatología , Retinopatía Diabética/fisiopatología , Progresión de la Enfermedad , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Apnea Obstructiva del Sueño/fisiopatología , Reino Unido
6.
Diabetologia ; 57(6): 1249-56, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24623102

RESUMEN

AIMS/HYPOTHESIS: The aim of this work was to assess the impact of cardiac autonomic neuropathy (CAN) on the development and progression of chronic kidney disease (CKD) in patients with type 2 diabetes. METHODS: We conducted a cohort study in adults with type 2 diabetes. Patients with end-stage renal disease were excluded. CKD was defined as the presence of albuminuria (albumin/creatinine ratio GFR > 3.4 mg/mmol) or an estimated (eGFR) < 60 ml min(-1) 1.73 m(-2). CKD progression was based on repeated eGFR measurements and/or the development of albuminuria. CAN was assessed using heart rate variability. RESULTS: Two hundred and four patients were included in the analysis. At baseline, the prevalence of CKD and CAN was 40% and 42%, respectively. Patients with CAN had lower eGFR and higher prevalence of albuminuria and CKD. Spectral analysis variables were independently associated with eGFR, albuminuria and CKD at baseline. After a follow-up of 2.5 years, eGFR declined to a greater extent in patients with CAN than in those without CAN (-9.0 ± 17.8% vs -3.3 ± 10.3%, p = 0.009). After adjustment for baseline eGFR and baseline differences, CAN remained an independent predictor of eGFR decline over the follow-up period (ß = -3.5, p = 0.03). Spectral analysis variables were also independent predictors of eGFR decline. CONCLUSIONS/INTERPRETATION: CAN was independently associated with CKD, albuminuria and eGFR in patients with type 2 diabetes. In addition, CAN was an independent predictor of the decline in eGFR over the follow-up period. CAN could be used to identify patients with type 2 diabetes who are at increased risk of rapid decline in eGFR, so that preventative therapies might be intensified.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Neuropatías Diabéticas/complicaciones , Insuficiencia Renal Crónica/etiología , Adulto , Anciano , Femenino , Tasa de Filtración Glomerular/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
7.
Health Qual Life Outcomes ; 12: 83, 2014 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-24902492

RESUMEN

BACKGROUND: The objective of this study was to investigate the association between ethnicity and health related quality of life (HRQoL) in patients with type 2 diabetes. METHODS: The EuroQol EQ-5D measure was administered to 1,978 patients with type 2 diabetes in the UK Asian Diabetes Study (UKADS): 1,486 of south Asian origin (Indian, Pakistani, Bangladeshi or other south Asian) and 492 of white European origin. Multivariate regression using ordinary least square (OLS), Tobit, fractional logit and Censored Least Absolutes Deviations estimators was used to estimate the impact of ethnicity on both visual analogue scale (VAS) and utility scores for the EuroQol EQ-5D. RESULTS: Mean EQ-5D VAS and utility scores were lower among south Asians with diabetes compared to the white European population; the unadjusted effect on the mean EQ-5D VAS score was -7.82 (Standard error [SE] = 1.06, p < 0.01) and on the EQ-5D utility score was -0.06 (SE = 0.02, p < 0.01) (OLS estimator). After controlling for socio-demographic and clinical confounders, the adjusted effect on the EQ-5D VAS score was -9.35 (SE = 2.46, p < 0.01) and on the EQ-5D utility score was 0.06 (SE = 0.04), although the latter was not statistically significant. CONCLUSIONS: There was a large and statistically significant association between south Asian ethnicity and lower EQ-5D VAS scores. In contrast, there was no significant difference in EQ-5D utility scores between the south Asian and white European sub-groups. Further research is needed to explain the differences in effects on subjective EQ-5D VAS scores and population-weighted EQ-5D utility scores in this context.


Asunto(s)
Diabetes Mellitus Tipo 2/etnología , Etnicidad/estadística & datos numéricos , Calidad de la Atención de Salud , Bangladesh/etnología , Diabetes Mellitus Tipo 2/psicología , Etnicidad/psicología , Femenino , Humanos , India/etnología , Masculino , Persona de Mediana Edad , Pakistán/etnología , Encuestas y Cuestionarios , Reino Unido/epidemiología , Escala Visual Analógica , Población Blanca/psicología , Población Blanca/estadística & datos numéricos
8.
J Chem Theory Comput ; 20(14): 5882-5900, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38950345

RESUMEN

A vibrational electronic-thermofield coupled cluster (VE-TFCC) approach is developed to calculate thermal properties of non-adiabatic vibronic coupling systems. The thermofield (TF) theory and a mixed linear exponential ansatz based on second-quantized Bosonic construction operators are introduced to propagate the thermal density operator as a "pure state" in the Bogoliubov representation. Through this compact representation of the thermal density operator, the approach is basis-set-free and scales classically (polynomial) as the number of degrees of freedoms (DoF) in the system increases. The VE-TFCC approach is benchmarked with small test models and a real molecular compound (CoF4- anion) against the conventional sum over states (SOS) method and applied to calculate thermochemistry properties of a gas-phase reaction: CoF3 + F- → CoF4-. Results shows that the VE-TFCC approach, in conjunction with vibronic models, provides an effective protocol for calculating thermodynamic properties of vibronic coupling systems.

9.
Am J Respir Crit Care Med ; 186(5): 434-41, 2012 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-22723291

RESUMEN

RATIONALE: Diabetic peripheral neuropathy is common and causes significant morbidity. Obstructive sleep apnea (OSA) is also common in patients with type 2 diabetes. Because OSA is associated with inflammation and oxidative stress, we hypothesized that OSA is associated with peripheral neuropathy in type 2 diabetes. OBJECTIVES: To assess the relationship between OSA and peripheral neuropathy in patients with type 2 diabetes. METHODS: A cross-sectional study of adults with type 2 diabetes recruited randomly from the diabetes clinic of two UK hospitals. MEASUREMENTS AND MAIN RESULTS: Peripheral neuropathy was diagnosed using the Michigan Neuropathy Screening Instrument. OSA (apnea-hypopnea index ≥ 5 events/h) was assessed using home-based, multichannel respiratory monitoring. Serum nitrotyrosine was measured by ELISA, lipid peroxide by spectrophotometer, and microvascular function by laser speckle contrast imaging. Two hundred thirty-four patients (mean [SD] age, 57 [12] yr) were analyzed. OSA prevalence was 65% (median apnea-hypopnea index, 7.2; range, 0-93), 40% of which were moderate to severe. Neuropathy prevalence was higher in patients with OSA than those without (60% vs. 27%, P < 0.001). After adjustment for possible confounders, OSA remained independently associated with diabetic neuropathy (odds ratio, 2.82; 95% confidence interval, 1.44-5.52; P = 0.0034). Nitrotyrosine and lipid peroxide levels (n = 102, 74 with OSA) were higher in OSA and correlated with hypoxemia severity. Cutaneous microvascular function (n = 71, 47 with OSA) was impaired in OSA. CONCLUSIONS: We describe a novel independent association between diabetic peripheral neuropathy and OSA. We identified increased nitrosative/oxidative stress and impaired microvascular regulation as potential mechanisms. Prospective and interventional studies are needed to assess the impact of OSA and its treatment on peripheral neuropathy development and progression in patients with type 2 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Neuropatías Diabéticas/etiología , Apnea Obstructiva del Sueño/complicaciones , Adulto , Anciano , Biomarcadores/sangre , Estudios Transversales , Diabetes Mellitus Tipo 2/sangre , Neuropatías Diabéticas/sangre , Neuropatías Diabéticas/epidemiología , Femenino , Humanos , Modelos Lineales , Peróxidos Lipídicos/sangre , Masculino , Microcirculación , Persona de Mediana Edad , Análisis Multivariante , Estrés Oxidativo , Prevalencia , Índice de Severidad de la Enfermedad , Piel/irrigación sanguínea , Apnea Obstructiva del Sueño/sangre , Apnea Obstructiva del Sueño/epidemiología , Apnea Obstructiva del Sueño/fisiopatología , Tirosina/análogos & derivados , Tirosina/sangre
10.
Transplantation ; 104(3): e65-e74, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31895342

RESUMEN

BACKGROUND: Understanding the outcomes and risks for live kidney donors (LD) is increasingly important; this study investigated all-cause mortality and morbidity outcomes of LD compared with a healthy cohort. METHODS: Live donor dataset was obtained from the UK Transplant Registry and a comparator nondonor cohort selected from The Health Improvement Network (THIN) database, a UK primary healthcare database. All LD from January 1, 2001, to December 31, 2013, were included, with follow-up until December 31, 2016. RESULTS: There were 9750 LD and 19 071 THIN participants. Median follow-up (interquartile range) for LD was 8.4 (6.0-11.3) years and for THIN was 5.4 (2.6-8.5) years. In up to 15 years, follow-up end-stage renal disease was observed in 1 LD versus 7 THIN (P = 0.280). Nine LD had estimated glomerular filtration rate of <30 mL/min/1.73 m versus 43 in THIN (P = 0.012), but no statistically significant difference in adjusted logistic regression analyses. Risk of diabetes mellitus, depression, and cardiovascular disease was significantly higher for THIN cohort in adjusted analyses. The risk of hypertension was higher for LD at 5 years but was not significantly different in fully adjusted analyses at 10 years. There were 68 deaths in LD and 485 in THIN over the follow-up period, with significant difference in mortality favoring LD (P < 0.001). CONCLUSIONS: The medium-term morbidity and mortality outcomes of live donors in comparison with a healthy cohort suggest that live donation is not associated with excess mortality, end-stage renal disease, or morbidity, in at least 10 years follow-up.


Asunto(s)
Fallo Renal Crónico/epidemiología , Donadores Vivos/estadística & datos numéricos , Nefrectomía/efectos adversos , Recolección de Tejidos y Órganos/efectos adversos , Adolescente , Adulto , Causas de Muerte , Conjuntos de Datos como Asunto , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Fallo Renal Crónico/etiología , Trasplante de Riñón/métodos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Factores de Riesgo , Reino Unido/epidemiología , Adulto Joven
11.
BMC Public Health ; 9: 175, 2009 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-19500375

RESUMEN

BACKGROUND: There is uncertainty as to whether there is a safe threshold for drinking alcohol during pregnancy. We explored pregnant women's attitudes towards drinking alcohol in pregnancy and their attitudes towards sources of information about drinking in pregnancy following recent changes in UK government guidance. METHODS: A qualitative study involving individual, semi-structured interviews with 20 pregnant women recruited from community organisations in the UK. Interview transcripts were analysed qualitatively using thematic analysis. RESULTS: Most women found information and advice about safe levels of drinking in pregnancy confusing and lacking in evidence and detail. Although most women considered that there were risks involved with drinking in pregnancy and these perceptions influenced their behaviour, only six women reported abstinence. Women reported being influenced by advice from family and friends and their experiences of previous pregnancies. Many had received no individual advice from general practitioners or midwives relating to drinking during pregnancy. CONCLUSION: Pregnant women wished to take responsibility for their own health and make choices based on informed advice. In order to do so, they require clear and consistent advice about safe levels of drinking from policy makers and health professionals. This is an important issue as women might drink socially during their pregnancy.


Asunto(s)
Consumo de Bebidas Alcohólicas/psicología , Conocimientos, Actitudes y Práctica en Salud , Mujeres Embarazadas/psicología , Atención Prenatal/métodos , Adulto , Consejo , Inglaterra , Femenino , Adhesión a Directriz , Humanos , Educación del Paciente como Asunto , Guías de Práctica Clínica como Asunto , Embarazo , Adulto Joven
12.
Transplantation ; 103(7): 1486-1493, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30801508

RESUMEN

BACKGROUND: A glass ceiling effect exists for women in male-dominated professions. Recent studies also show a glass-cliff effect where senior women can more easily fall from positions of leadership. Transplantation remains a male-dominated specialty. This study investigated gender and the perception of adverse clinical incidents in transplantation. METHODS: Prospective randomised web-based survey involving five clinical scenarios presenting two versions of episodes with errors or mistakes, with either a male or female as a randomly named protagonist (Set1 and Set2). To address unconscious bias, the study was described as examining actions following clinical adverse incidents in transplantation. Each scenario was followed by 2 closed questions: (1) clinical performance rating and (2) selection of action required. Reasoning was invited (open-text comments). Responses were analyzed using quantitative and qualitative methods. RESULTS: One hundred ninety-one invitees responded; 134 completed questionnaires. There were no statistically significant differences (P > 0.05) in responses between sets for performance ratings or recommended actions. However, for "first solo laparoscopic surgery" scenario, there was some indication that "No Action" was more likely if surgeon was male (P = 0.056). Male responses rated female performance as significantly worse (P = 0.035) for the laboratory-based scenario. One hundred two participants provided open-text comments. Thematic analysis identified 7 themes. Acceptable levels of risk theme demonstrated engendered leadership beliefs, that is, when clinical judgment proved incorrect, males described as forceful but females as needing support. In cases where things went wrong, respondents were more likely to comment females should not have decided to proceed. CONCLUSIONS: While gender may no longer be an overt issue in perceived performance of senior staff in transplantation, respondents' use of language and their choice of words display elements of unconscious (covert) engendered views.


Asunto(s)
Errores Médicos , Trasplante de Órganos/efectos adversos , Rol del Médico , Médicos Mujeres , Sexismo , Cirujanos , Mujeres Trabajadoras , Adulto , Actitud del Personal de Salud , Selección de Profesión , Movilidad Laboral , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Liderazgo , Masculino , Persona de Mediana Edad , Trasplante de Órganos/mortalidad , Seguridad del Paciente , Estudios Prospectivos , Investigación Cualitativa , Medición de Riesgo , Factores de Riesgo , Adulto Joven
13.
Curr Med Res Opin ; 35(11): 1893-1900, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31251092

RESUMEN

Background: Early onset of type 2 diabetes (T2DM) is associated with prolonged exposure to hyperglycaemia and increased propensity to chronic complications. The aim of this study was to characterize and compare the phenotypic characteristics and risk factors in a multi-ethnic cohort of young adults with type 2 diabetes (T2DMY). Methods: One hundred young adults (White European [WE], South Asian [SA] and African-Caribbean [AC]) diagnosed with T2DM before the age of 40 years were recruited. Demographics, family history, diabetes related complications, co-morbidities, anthropometry (body mass index [BMI], body composition), physical activity and biochemistry (HbA1c, lipid profile, liver and renal function) and autoantibodies (anti GAD, anti islet cell) were collected for all participants. Data were analysed for the most represented ethnic groups: (WE, N = 36 and SA, N = 53) using SPSS version 23. Results: Mean (± standard deviation) age at diagnosis was 32.5 ± 5.5 years and mean diabetes duration was 7.7 ± 3.8 years. Overweight/obesity was present in 95% of participants, history of maternal diabetes in 68%, deprivation 75%, low physical activity 40%, polycystic ovarian disease 29% (in females), acanthosis nigricans 12% and non-alcoholic fatty liver 11%. There was considerable clustering of risk factors within the cohort with over 75% of all subjects having three or more of the above risk factors and 52% required insulin within 3 years of diagnosis. Two-thirds of the patients had evidence of at least one diabetes related microvascular complication. Conclusion: T2DMY is characterized by a high burden of commonly associated risk factors for both the disease and its long-term complications.


Asunto(s)
Diabetes Mellitus Tipo 2/etiología , Adulto , Estudios de Cohortes , Diabetes Mellitus Tipo 2/etnología , Ejercicio Físico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Fenotipo , Factores de Riesgo , Adulto Joven
14.
Kidney Int ; 74(10): 1343-53, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18784644

RESUMEN

To examine any potential role for 1,25-dihydroxyvitamin D (1,25(OH)2D) in inflammation associated with chronic kidney disease we measured vitamin D metabolites, markers of inflammation and gene expression in 174 patients with a variety of kidney diseases. Urinary MCP-1 protein and renal macrophage infiltration were each significantly but inversely correlated with serum 1,25(OH)2D levels. Logistic regression analysis with urinary MCP-1 as binary outcome showed that a 10-unit increase in serum 1,25(OH)2D or 25OHD resulted in lower renal inflammation. Analysis of 111 renal biopsies found that renal injury was not associated with a compensatory increase in mRNA for the vitamin D-activating enzyme 25-hydroxyvitamin D-1alpha-hydroxylase (CYP27B1), its catabolic counterpart 24-hydroxylase, or the vitamin D receptor. There was, however, a significant association between tissue MCP-1 and CYP27B1. Patients with acute renal inflammation had a significant increase in urinary and tissue MCP-1, macrophage infiltration, and macrophage and renal epithelial CYP27B1 expression but significantly lower levels of serum 1,25(OH)2D in comparison to patients with chronic ischemic disease despite similar levels of renal damage. In vitro, 1,25(OH)2D attenuated TNFalpha-induced MCP-1 expression by human proximal tubule cells. Our study indicates that renal inflammation is associated with decreased serum vitamin D metabolites and involves activation of the paracrine/autocrine vitamin D system.


Asunto(s)
Inflamación/etiología , Enfermedades Renales/patología , Vitamina D/sangre , 25-Hidroxivitamina D3 1-alfa-Hidroxilasa/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Comunicación Autocrina , Quimiocina CCL2/análisis , Enfermedad Crónica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Comunicación Paracrina , ARN Mensajero/análisis , Vitamina D/análogos & derivados , Vitamina D/metabolismo , Adulto Joven
15.
PLoS One ; 13(7): e0200354, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29995947

RESUMEN

BACKGROUND AND OBJECTIVES: Exercise capacity is reduced in chronic kidney failure (CKF). Intra-dialytic cycling is beneficial, but comorbidity and fatigue can prevent this type of training. Low-frequency electrical muscle stimulation (LF-EMS) of the quadriceps and hamstrings elicits a cardiovascular training stimulus and may be a suitable alternative. The main objectives of this trial were to assess the feasibility and efficacy of intra-dialytic LF-EMS vs. cycling. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: Assessor blind, parallel group, randomized controlled pilot study with sixty-four stable patients on maintenance hemodialysis. Participants were randomized to 10 weeks of 1) intra-dialytic cycling, 2) intra-dialytic LF-EMS, or 3) non-exercise control. Exercise was performed for up to one hour three times per week. Cycling workload was set at 40-60% oxygen uptake (VO2) reserve, and LF-EMS at maximum tolerable intensity. The control group did not complete any intra-dialytic exercise. Feasibility of intra-dialytic LF-EMS and cycling was the primary outcome, assessed by monitoring recruitment, retention and tolerability. At baseline and 10 weeks, secondary outcomes including cardio-respiratory reserve, muscle strength, and cardio-arterial structure and function were assessed. RESULTS: Fifty-one (of 64 randomized) participants completed the study (LF-EMS = 17 [77%], cycling = 16 [80%], control = 18 [82%]). Intra-dialytic LF-EMS and cycling were feasible and well tolerated (9% and 5% intolerance respectively, P = 0.9). At 10-weeks, cardio-respiratory reserve (VO2 peak) (Difference vs. control: LF-EMS +2.0 [95% CI, 0.3 to 3.7] ml.kg-1.min-1, P = 0.02, and cycling +3.0 [95% CI, 1.2 to 4.7] ml.kg-1.min-1, P = 0.001) and leg strength (Difference vs. control: LF-EMS, +94 [95% CI, 35.6 to 152.3] N, P = 0.002 and cycling, +65.1 [95% CI, 6.4 to 123.8] N, P = 0.002) were improved. Arterial structure and function were unaffected. CONCLUSIONS: Ten weeks of intra-dialytic LF-EMS or cycling improved cardio-respiratory reserve and muscular strength. For patients who are unable or unwilling to cycle during dialysis, LF-EMS is a feasible alternative.


Asunto(s)
Ciclismo , Terapia por Estimulación Eléctrica , Terapia por Ejercicio , Músculos Isquiosurales , Fallo Renal Crónico/terapia , Músculo Cuádriceps , Adulto , Ciclismo/fisiología , Capacidad Cardiovascular , Estudios de Factibilidad , Femenino , Músculos Isquiosurales/fisiopatología , Humanos , Fallo Renal Crónico/diagnóstico por imagen , Fallo Renal Crónico/fisiopatología , Masculino , Persona de Mediana Edad , Fuerza Muscular , Proyectos Piloto , Músculo Cuádriceps/fisiopatología , Diálisis Renal , Rigidez Vascular
16.
J Clin Sleep Med ; 13(4): 583-589, 2017 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-28162147

RESUMEN

STUDY OBJECTIVES: To assess and compare obstructive sleep apnea (OSA) prevalence in South Asians and White Europeans with type 2 diabetes mellitus (T2DM). Secondary aims included exploring possible causes for observed ethnic differences. METHODS: A cross-sectional study of patients with T2DM recruited from secondary care diabetes clinics. OSA was defined as an apnea-hypopnea index (AHI) ≥ 5 events/h using home-based, multi-channel respiratory monitoring. RESULTS: Two hundred thirty-four patients (105 South Asian and 129 White Europeans) were studied. The prevalence of mild, moderate, and severe OSA in South Asians was 36.2% (n = 38/105), 9.5% (n = 10/105), and 5.7% (n = 6/105) respectively. After adjustment, OSA was associated with a higher body mass index in South Asians. OSA was significantly less common in South Asians compared to White Europeans (51.4% [54/105] versus 75.2% [97/129], P < .001). OSA was also less severe in South Asians compared to White Europeans (median [interquartile range]: AHI 5.1 [1.4-11.5] versus 8.5 [5.0-20.7] events/h, P < .001; time spent with oxygen saturations < 90% 0.5 [0.0-2.9]% versus 4.0 [0.7-14.4]%, P < .001). Logistic regression showed that only obesity measures explained the ethnic differences in OSA. CONCLUSIONS: South Asians with T2DM are at considerable risk of OSA. OSA in South Asians was associated with obesity. However, OSA prevalence was lower in South Asians than in White Europeans. Obesity measures accounted for the observed ethnic differences. Examining factors contributing to ethnic differences will be important to inform screening and treatment strategies.


Asunto(s)
Pueblo Asiatico/estadística & datos numéricos , Diabetes Mellitus Tipo 2/epidemiología , Apnea Obstructiva del Sueño/epidemiología , Población Blanca/estadística & datos numéricos , Asia/epidemiología , Comorbilidad , Estudios Transversales , Europa (Continente)/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo
17.
Diab Vasc Dis Res ; 3(1): 22-5, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16784177

RESUMEN

Microalbuminuria is more common in South Asian individuals compared to white Europeans. The aim of this study was to determine the relationship between blood pressure and microalbuminuria in a cohort of patients with type 2 diabetes in these two ethnic groups. These further data were analysed from 552 patients (311 South Asian patients and 241 white Europeans) who had microalbuminuria screening data collected. Prevalence of microalbuminuria was significantly higher in South Asian compared with white European patients (31% versus 20%, p=0.007). Among patients with normal, untreated blood pressure, the proportion who had microalbuminuria was three times higher among South Asian patients compared with the white European group (30.7% versus 10.1%, p=0.049, relative risk = 3.1 [1.0-9.5]). In addition, despite their higher cardiovascular risk, South Asian patients were less likely to be prescribed a statin or antihypertensive drug treatment. In conclusion, thresholds and targets for treatment of cardiovascular risk factors in South Asians may need to be lower than those for white Europeans, and targeted intervention will be required to achieve this.


Asunto(s)
Albuminuria/etnología , Pueblo Asiatico , Diabetes Mellitus Tipo 2/complicaciones , Hipertensión/etnología , Población Blanca , Adulto , Anciano , Anciano de 80 o más Años , Albuminuria/etiología , Femenino , Humanos , Hipertensión/etiología , Masculino , Persona de Mediana Edad , Prevalencia , Reino Unido/epidemiología
18.
Br J Gen Pract ; 56(528): 511-7, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16834877

RESUMEN

BACKGROUND: Tight glycaemic control in people with type 2 diabetes can lead to a reduction in microvascular and possibly macrovascular complications. The use of near-patient (rapid) testing offers a potential method to improve glycaemic control. AIM: To assess the effect and costs of rapid testing for glycated haemoglobin (HbA1c) in people with type 2 diabetes. DESIGN OF STUDY: Pragmatic open randomised controlled trial. SETTING: Eight practices in Leicestershire, UK. METHOD: Patients were randomised to receive instant results for HbA1c or to routine care. The principal outcome measure was the proportion of patients with an HbA1c <7% at 12 months. We also assessed costs for the two groups. RESULTS: Of the 681 patients recruited to the study 638 (94%) were included in the analysis. The mean age at baseline was 65.7 years (SD = 10.8 years) with a median (interquartile range) duration of diabetes of 4(1-8) years. The proportion of patients with HbA1c < 7% did not differ significantly between the intervention and control groups (37 versus 38%, odds ratio 0.95 [95% confidence interval = 0.69 to 1.31]) at 12 months follow up. The total cost for diabetes-related care was 390 UK pounds per patient for the control group and 370 UK pounds for the intervention group. This difference was not statistically significant. CONCLUSION: Near-patient testing for HbA1c alone does not lead to outcome or cost benefits in managing people with type 2 diabetes in primary care. Further research is required into the use of rapid testing as part of an optimised patient management model including arrangements for patient review and testing.


Asunto(s)
Diabetes Mellitus Tipo 2/sangre , Hemoglobina Glucada/análisis , Sistemas de Atención de Punto , Anciano , Glucemia/metabolismo , Costos y Análisis de Costo , Diabetes Mellitus Tipo 2/economía , Medicina Familiar y Comunitaria/economía , Medicina Familiar y Comunitaria/organización & administración , Femenino , Humanos , Hiperglucemia/economía , Hiperglucemia/prevención & control , Hipoglucemia/economía , Hipoglucemia/prevención & control , Masculino , Sistemas de Atención de Punto/economía , Estudios Prospectivos
19.
J Diabetes Complications ; 30(7): 1315-20, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27324704

RESUMEN

BACKGROUND: Obstructive sleep apnea (OSA) is associated with increased nitrosative stress, endothelial dysfunction, and peripheral neuropathy in patients with type 2 diabetes. We hypothesized that OSA is associated with Poly ADP ribose polymerase (PARP) activation, lower intra-epidermal nerve fiber density (IENFD), and diabetic foot ulceration (DFU). METHODS: A cross-sectional study of adults with type 2 diabetes recruited from a secondary care hospital in the UK. OSA was assessed by multi-channel home-based cardio-respiratory device (Alice PDX, Philips Respironics). DPN was assessed using the Michigan Neuropathy Screening Instrument (MNSI). IENFD and % PAR stained nuclei were assessed using immunohistochemistry staining on skin biopsies. DFU was assessed based on MNSI. RESULTS: Skin biopsies and DFU data were available from 52 and 234 patients respectively. OSA was associated with lower IENFD (12.75±1.93 vs. 10.55±1.62 vs. 9.42±1.16 fibers/mm of epidermis for no OSA, mild OSA and moderate to severe OSA respectively, p<0.001). Following adjustment, mild (B=-2.19, p=0.002) and moderate to severe OSA (B=-3.45, p<0.001) were independently associated with IENFD. The apnea hypopnea index (AHI) was associated with IENFD following adjustment (B=-2.45, p<0.001). AHI was associated with percentage of PAR stained nuclei following adjustment (B=13.67, p=0.025). DFU prevalence was greater in patients with OSA (7.1% vs. 28.1% vs. 26.2% for patients with no OSA, mild OSA and moderate to severe OSA respectively, p=0.001). Following adjustment, OSA was associated with DFU (OR 3.34, 95% CI 1.19-9.38, p=0.022). CONCLUSIONS: OSA is associated with lower IENFD, PARP activation and DFU in patients with type 2 diabetes. Our findings suggest that OSA is associated with small fiber neuropathy. PARP activation is a potential mechanisms linking OSA to DPN and endothelial dysfunction in patients with type 2 diabetes. Whether OSA treatment will have a favorable impact on these parameters and DFU requires interventional studies.


Asunto(s)
Diabetes Mellitus Tipo 2/patología , Pie Diabético/epidemiología , Epidermis/inervación , Fibras Nerviosas/fisiología , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Apnea Obstructiva del Sueño/epidemiología , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Michigan , Persona de Mediana Edad
20.
Diabetes ; 53(11): 2998-3001, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15504982

RESUMEN

We have recently shown that permanent neonatal diabetes can be caused by activating mutations in KCNJ11 that encode the Kir6.2 subunit of the beta-cell ATP-sensitive K(+) channel. Some of these patients were diagnosed after 3 months of age and presented with ketoacidosis and marked hyperglycemia, which could have been diagnosed as type 1 diabetes. We hypothesized that KCNJ11 mutations could present clinically as type 1 diabetes. We screened the KCNJ11 gene for mutations in 77 U.K. type 1 diabetic subjects diagnosed under the age of 2 years. One patient was found to be heterozygous for the missense mutation R201C. She had low birth weight, was diagnosed at 5 weeks, and did not have a high risk predisposing HLA genotype. A novel variant, R176C, was identified in one diabetic subject but did not cosegregate with diabetes within the family. In conclusion, we have shown that heterozygous activating mutations in the KCNJ11 gene are a rare cause of clinically defined type 1 diabetes diagnosed before 2 years. Although activating KCNJ11 mutations are rare in patients diagnosed with type 1 diabetes, the identification of a KCNJ11 mutation may have important treatment implications.


Asunto(s)
Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/genética , Mutación/genética , Canales de Potasio de Rectificación Interna/genética , Femenino , Variación Genética , Genoma Humano , Humanos , Masculino
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