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1.
Alzheimers Res Ther ; 16(1): 112, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762725

RESUMEN

BACKGROUND: Alzheimer's disease (AD) is characterized by the accumulation of amyloid-ß (Aß) plaques, neurofibrillary tau tangles, and neurodegeneration in the brain parenchyma. Here, we aimed to (i) assess differences in blood and imaging biomarkers used to evaluate neurodegeneration among cognitively unimpaired APOE ε4 homozygotes, heterozygotes, and non-carriers with varying risk for sporadic AD, and (ii) to determine how different cerebral pathologies (i.e., Aß deposition, medial temporal atrophy, and cerebrovascular pathology) contribute to blood biomarker concentrations in this sample. METHODS: Sixty APOE ε4 homozygotes (n = 19), heterozygotes (n = 21), and non-carriers (n = 20) ranging from 60 to 75 years, were recruited in collaboration with Auria biobank (Turku, Finland). Participants underwent Aß-PET ([11C]PiB), structural brain MRI including T1-weighted and T2-FLAIR sequences, and blood sampling for measuring serum neurofilament light chain (NfL), plasma total tau (t-tau), plasma N-terminal tau fragments (NTA-tau) and plasma glial fibrillary acidic protein (GFAP). [11C]PiB standardized uptake value ratio was calculated for regions typical for Aß accumulation in AD. MRI images were analysed for regional volumes, atrophy scores, and volumes of white matter hyperintensities. Differences in biomarker levels and associations between blood and imaging biomarkers were tested using uni- and multivariable linear models (unadjusted and adjusted for age and sex). RESULTS: Serum NfL concentration was increased in APOE ε4 homozygotes compared with non-carriers (mean 21.4 pg/ml (SD 9.5) vs. 15.5 pg/ml (3.8), p = 0.013), whereas other blood biomarkers did not differ between the groups (p > 0.077 for all). From imaging biomarkers, hippocampal volume was significantly decreased in APOE ε4 homozygotes compared with non-carriers (6.71 ml (0.86) vs. 7.2 ml (0.7), p = 0.029). In the whole sample, blood biomarker levels were differently predicted by the three measured cerebral pathologies; serum NfL concentration was associated with cerebrovascular pathology and medial temporal atrophy, while plasma NTA-tau associated with medial temporal atrophy. Plasma GFAP showed significant association with both medial temporal atrophy and Aß pathology. Plasma t-tau concentration did not associate with any of the measured pathologies. CONCLUSIONS: Only increased serum NfL concentrations and decreased hippocampal volume was observed in cognitively unimpaired APOEε4 homozygotes compared to non-carriers. In the whole population the concentrations of blood biomarkers were affected in distinct ways by different pathologies.


Asunto(s)
Péptidos beta-Amiloides , Apolipoproteína E4 , Atrofia , Biomarcadores , Tomografía de Emisión de Positrones , Proteínas tau , Humanos , Femenino , Masculino , Anciano , Biomarcadores/sangre , Atrofia/patología , Persona de Mediana Edad , Apolipoproteína E4/genética , Proteínas tau/sangre , Péptidos beta-Amiloides/sangre , Imagen por Resonancia Magnética/métodos , Proteínas de Neurofilamentos/sangre , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/patología , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Heterocigoto , Proteína Ácida Fibrilar de la Glía/sangre , Compuestos de Anilina , Tiazoles
2.
Am J Physiol Endocrinol Metab ; 326(4): E503-E514, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38416072

RESUMEN

Metabolic flexibility (MetFlex) describes the ability to respond and adapt to changes in metabolic demand and substrate availability. The relationship between physical (in)activity and MetFlex is unclear. This study aimed to determine whether sedentary time, physical activity (PA), and cardiorespiratory fitness associate with MetFlex. Sedentary time, standing, and PA were measured with accelerometers for 4 weeks in 64 sedentary adults with metabolic syndrome [37 women, 27 men; 58.3 (SD 6.8) years]. Fitness (V̇o2max; mL·kg-1·min-1) was measured with graded maximal cycle ergometry. MetFlex was assessed with indirect calorimetry as the change in respiratory exchange ratio (ΔRER) from fasting to insulin stimulation with hyperinsulinemic-euglycemic clamp and from low-intensity to maximal exercise. Carbohydrate (CHOox) and fat oxidation (FATox) were calculated from respiratory gases. High sedentary time associated with higher fasting RER [ß = 0.35 (95% confidence interval: 0.04, 0.67)], impaired insulin-stimulated MetFlex (ΔRER) [ß=-0.41 (-0.72, -0.09)], and lower fasting FATox [ß=-0.36 (-0.67, -0.04)]. Standing associated with lower fasting RER [ß=-0.32 (-0.62, -0.02)]. Higher standing time and steps/day associated with higher fasting FATox [ß = 0.31 (0.01, 0.61), and ß = 0.26 (0.00, 0.53)]. Light-intensity and total PA associated with better insulin-stimulated MetFlex [ß = 0.33 (0.05, 0.61)], and ß = 0.33 (0.05, 0.60)]. Higher V̇o2max associated with higher CHOox during maximal exercise [ß = 0.81 (0.62, 1.00)], as well as during insulin stimulation [ß = 0.43 (0.13, 0.73)]. P values are less than 0.05 for all associations. Sedentary time and PA associate with MetFlex. Reducing sitting and increasing PA of even light intensity might aid in the prevention of metabolic diseases in risk populations through their potential effects on energy metabolism.NEW & NOTEWORTHY High accelerometer-assessed sedentary time associates with metabolic inflexibility measured during hyperinsulinemic-euglycemic clamp in adults with metabolic syndrome, and more light-intensity and total physical activity associate with more metabolic flexibility. Physical activity behaviors may thus play an important role in the regulation of fuel metabolism. This highlights the potential of reduced sedentary time and increased physical activity of any intensity to induce metabolic health benefits and help in disease prevention in risk populations.


Asunto(s)
Resistencia a la Insulina , Síndrome Metabólico , Masculino , Adulto , Humanos , Femenino , Resistencia a la Insulina/fisiología , Conducta Sedentaria , Ejercicio Físico/fisiología , Insulina
3.
Am J Physiol Endocrinol Metab ; 325(2): E152-E162, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37378623

RESUMEN

Sedentary behavior (SB) and physical inactivity associate with impaired insulin sensitivity. We investigated whether an intervention aimed at a 1-h reduction in daily SB during 6 mo would improve insulin sensitivity in the weight-bearing thigh muscles. Forty-four sedentary inactive adults [mean age 58 (SD 7) yr; 43% men] with metabolic syndrome were randomized into intervention and control groups. The individualized behavioral intervention was supported by an interactive accelerometer and a mobile application. SB, measured with hip-worn accelerometers in 6-s intervals throughout the 6-mo intervention, decreased by 51 (95% CI 22-80) min/day and physical activity (PA) increased by 37 (95% CI 18-55) min/day in the intervention group with nonsignificant changes in these outcomes in the control group. Insulin sensitivity in the whole body and in the quadriceps femoris and hamstring muscles, measured with hyperinsulinemic-euglycemic clamp combined with [18F]fluoro-deoxy-glucose PET, did not significantly change during the intervention in either group. However, the changes in hamstring and whole body insulin sensitivity correlated inversely with the change in SB and positively with the changes in moderate-to-vigorous PA and daily steps. In conclusion, these results suggest that the more the participants were able to reduce their SB, the more their individual insulin sensitivity increased in the whole body and in the hamstring muscles but not in quadriceps femoris. However, according to our primary randomized controlled trial results, this kind of behavioral interventions targeted to reduce sedentariness may not be effective in increasing skeletal muscle and whole body insulin sensitivity in people with metabolic syndrome at the population level.NEW & NOTEWORTHY Aiming to reduce daily SB by 1 h/day had no impact on skeletal muscle insulin sensitivity in the weight-bearing thigh muscles. However, successfully reducing SB may increase insulin sensitivity in the postural hamstring muscles. This emphasizes the importance of both reducing SB and increasing moderate-to-vigorous physical activity to improve insulin sensitivity in functionally different muscles of the body and thus induce a more comprehensive change in insulin sensitivity in the whole body.


Asunto(s)
Resistencia a la Insulina , Síndrome Metabólico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ejercicio Físico/fisiología , Músculo Esquelético , Conducta Sedentaria , Anciano
4.
Neurobiol Dis ; 183: 106175, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37268240

RESUMEN

Plasma phosphorylated tau (p-tau) and glial fibrillary acidic protein (GFAP) both reflect early changes in Alzheimer's disease (AD) pathology. Here, we compared the biomarker levels and their association with regional ß-amyloid (Aß) pathology and cognitive performance head-to-head in clinically unimpaired elderly (n = 88) at three levels of APOE4-related genetic risk for sporadic AD (APOE4/4 n = 19, APOE3/4 n = 32 or non-carriers n = 37). Concentrations of plasma p-tau181, p-tau231 and GFAP were measured using Single molecule array (Simoa), regional Aß deposition with 11C-PiB positron emission tomography (PET), and cognitive performance with a preclinical composite. Significant differences in plasma p-tau181 and p-tau231, but not plasma GFAP concentrations were present between the APOE4 gene doses, explained solely by brain Aß load. All plasma biomarkers correlated positively with Aß PET in the total study population. This correlation was driven by APOE3/3 carriers for plasma p-tau markers and APOE4/4 carriers for plasma GFAP. Voxel-wise associations with amyloid-PET revealed different spatial patterns for plasma p-tau markers and plasma GFAP. Only higher plasma GFAP correlated with lower cognitive scores. Our observations suggest that plasma p-tau and plasma GFAP are both early AD markers reflecting different Aß-related processes.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Anciano , Humanos , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/genética , Apolipoproteína E4/genética , Proteína Ácida Fibrilar de la Glía , Apolipoproteína E3 , Proteínas tau , Péptidos beta-Amiloides , Biomarcadores , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/genética
5.
J Cereb Blood Flow Metab ; 43(9): 1588-1600, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37113066

RESUMEN

Metabolic risk factors are associated with peripheral low-grade inflammation and an increased risk for dementia. We evaluated if metabolic risk factors i.e. insulin resistance, body mass index (BMI), serum cholesterol values, or high sensitivity C-reactive protein associate with central inflammation or beta-amyloid (Aß) accumulation in the brain, and if these associations are modulated by APOE4 gene dose. Altogether 60 cognitively unimpaired individuals (mean age 67.7 years (SD 4.7); 63% women; 21 APOE3/3, 20 APOE3/4 and 19 APOE4/4) underwent positron emission tomography with [11C]PK11195 targeting TSPO (18 kDa translocator protein) and [11C]PIB targeting fibrillar Aß. [11C]PK11195 distribution value ratios and [11C]PIB standardized uptake values were calculated in a cortical composite region of interest typical for Aß accumulation in Alzheimer's disease. Associations between metabolic risk factors, [11C]PK11195, and [11C]PIB uptake were evaluated with linear models adjusted for age and sex. Higher logarithmic HOMA-IR (standardized beta 0.40, p = 0.002) and BMI (standardized beta 0.27, p = 0.048) were associated with higher TSPO availability. Voxel-wise analyses indicated that this association was mainly seen in the parietal cortex. Higher logarithmic HOMA-IR was associated with higher [11C]PIB (standardized beta 0.44, p = 0.02), but only in APOE4/4 homozygotes. BMI and HOMA-IR seem to influence TSPO availability in the brain.


Asunto(s)
Enfermedad de Alzheimer , Índice de Masa Corporal , Resistencia a la Insulina , Receptores de GABA , Humanos , Estudios Transversales , Tomografía de Emisión de Positrones , Proteína C-Reactiva/análisis , LDL-Colesterol/sangre , HDL-Colesterol/sangre , Masculino , Femenino , Anciano , Análisis de Regresión , Inflamación/metabolismo , Demencia/patología , Receptores de GABA/metabolismo , Apolipoproteínas E/genética , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología
6.
Alzheimers Res Ther ; 15(1): 71, 2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-37016464

RESUMEN

BACKGROUND: Neuroinflammation, characterized by increased reactivity of microglia and astrocytes in the brain, is known to be present at various stages of the Alzheimer's disease (AD) continuum. However, its presence and relationship with amyloid pathology in cognitively normal at-risk individuals is less clear. Here, we used positron emission tomography (PET) and blood biomarker measurements to examine differences in neuroinflammation and beta-amyloid (Aß) and their association in cognitively unimpaired homozygotes, heterozygotes, or non-carriers of the APOE ε4 allele, the strongest genetic risk for sporadic AD. METHODS: Sixty 60-75-year-old APOE ε4 homozygotes (n = 19), heterozygotes (n = 21), and non-carriers (n = 20) were recruited in collaboration with the local Auria biobank. The participants underwent 11C-PK11195 PET (targeting 18-kDa translocator protein, TSPO), 11C-PiB PET (targeting Aß), brain MRI, and neuropsychological testing including a preclinical cognitive composite (APCC). 11C-PK11195 distribution volume ratios and 11C-PiB standardized uptake value ratios (SUVRs) were calculated for regions typical for early Aß accumulation in AD. Blood samples were drawn for measuring plasma glial fibrillary acidic protein (GFAP) and plasma Aß1-42/1.40. RESULTS: In our cognitively unimpaired sample, cortical 11C-PiB-binding increased according to APOE ε4 gene dose (median composite SUVR 1.47 (range 1.38-1.66) in non-carriers, 1.55 (1.43-2.02) in heterozygotes, and 2.13 (1.61-2.83) in homozygotes, P = 0.002). In contrast, cortical composite 11C-PK11195-binding did not differ between the APOE ε4 gene doses (P = 0.27) or between Aß-positive and Aß-negative individuals (P = 0.81) and associated with higher Aß burden only in APOE ε4 homozygotes (Rho = 0.47, P = 0.043). Plasma GFAP concentration correlated with cortical 11C-PiB (Rho = 0.35, P = 0.040), but not 11C-PK11195-binding (Rho = 0.13, P = 0.47) in Aß-positive individuals. In the total cognitively unimpaired population, both higher composite 11C-PK11195-binding and plasma GFAP were associated with lower hippocampal volume, whereas elevated 11C-PiB-binding was associated with lower APCC scores. CONCLUSIONS: Only Aß burden measured by PET, but not markers of neuroinflammation, differed among cognitively unimpaired elderly with different APOE ε4 gene dose. However, APOE ε4 gene dose seemed to modulate the association between neuroinflammation and Aß.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Apolipoproteína E4 , Dosificación de Gen , Anciano , Humanos , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/metabolismo , Apolipoproteína E4/genética , Biomarcadores , Genotipo , Enfermedades Neuroinflamatorias , Tomografía de Emisión de Positrones , Receptores de GABA/genética
7.
Med Sci Sports Exerc ; 55(3): 342-353, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36251378

RESUMEN

PURPOSE: This study aimed to investigate whether a reduction in daily sedentary behavior (SB) improves insulin sensitivity in adults with metabolic syndrome in 6 months, without adding intentional exercise training. METHODS: Sixty-four sedentary inactive middle-age adults with overweight and metabolic syndrome (mean (SD) age, 58 (7) yr; mean (SD) body mass index, 31.6 (4.3) kg·m -2 ; 27 men) were randomized into intervention and control groups. The 6-month individualized behavioral intervention supported by an interactive accelerometer and a mobile application aimed at reducing daily SB by 1 h compared with baseline. Insulin sensitivity by hyperinsulinemic euglycemic clamp, body composition by air displacement plethysmography, and fasting blood samples were analyzed before and after the intervention. SB and physical activity were measured with hip-worn accelerometers throughout the intervention. RESULTS: SB decreased by 40 (95% confidence interval, 17-65) min·d -1 , and moderate-to-vigorous physical activity increased by 20 (95% confidence interval, 11-28) min·d -1 on average in the intervention group with no significant changes in these outcomes in the control group. After 6 months, fasting plasma insulin decreased (~1 mU·L -1 ) in the intervention group compared with the control group (time-group, P = 0.0081), but insulin sensitivity did not change in either group. The changes in body mass or adiposity did not differ between groups. Among all participants, the changes in SB and body mass correlated inversely with the change in insulin sensitivity ( r = -0.31, -0.44; P = 0.025, 0.0005, respectively). CONCLUSIONS: An intervention aimed at reducing daily SB resulted in slightly decreased fasting insulin, but had no effects on insulin sensitivity or body adiposity. However, as the change in insulin sensitivity associated with the changes in SB and body mass, multifaceted interventions targeting to weight loss are likely to be beneficial in improving whole-body insulin sensitivity.


Asunto(s)
Resistencia a la Insulina , Síndrome Metabólico , Masculino , Adulto , Persona de Mediana Edad , Humanos , Conducta Sedentaria , Síndrome Metabólico/terapia , Obesidad , Insulina
8.
Scand J Med Sci Sports ; 33(3): 353-358, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36517882

RESUMEN

OBJECTIVE: The objective of the study was to investigate the associations of sedentary time, physical activity, and cardiorespiratory fitness with skeletal muscle glucose uptake (GU). METHODS: Sedentary time and physical activity were measured with accelerometers and VO2 max with cycle ergometry in 44 sedentary adults with metabolic syndrome. Thigh muscle GU was determined with [18 F]FDG-PET imaging. RESULTS: Sedentary time (ß = -0.374), standing (ß = 0.376), steps (ß = 0.351), and VO2 max (ß = 0.598) were associated with muscle GU when adjusted for sex, age, and accelerometer wear time. Adjustment for body fat-% turned all associations non-significant. CONCLUSION: Body composition is a more important determinant of muscle GU in this population than sedentary time, physical activity, or fitness.


Asunto(s)
Capacidad Cardiovascular , Síndrome Metabólico , Humanos , Adulto , Síndrome Metabólico/metabolismo , Conducta Sedentaria , Ejercicio Físico , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/metabolismo , Glucosa/metabolismo , Aptitud Física
10.
Front Neurol ; 13: 826423, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35222254

RESUMEN

BACKGROUND: Detailed characterization of early pathophysiological changes in preclinical Alzheimer's disease (AD) is necessary to enable development of correctly targeted and timed disease-modifying treatments. ASIC-E4 study ("Beta-Amyloid, Synaptic loss, Inflammation and Cognition in healthy APOE ε4 carriers") combines state-of-the-art neuroimaging and fluid-based biomarker measurements to study the early interplay of three key pathological features of AD, i.e., beta-amyloid (Aß) deposition, neuroinflammation and synaptic dysfunction and loss in cognitively normal volunteers with three different levels of genetic (APOE-related) risk for late-onset AD. OBJECTIVE: Here, our objective is to describe the study design, used protocols and baseline demographics of the ASIC-E4 study. METHODS/DESIGN: ASIC-E4 is a prospective observational multimodal imaging study performed in Turku PET Centre in collaboration with University of Gothenburg. Cognitively normal 60-75-year-old-individuals with known APOE ε4/ε4 genotype were recruited via local Auria Biobank (Turku, Finland). Recruitment of the project has been completed in July 2020 and 63 individuals were enrolled to three study groups (Group 1: APOE ε4/ε4, N = 19; Group 2: APOE ε4/ε3, N = 22; Group 3: APOE ε3/ε3, N = 22). At baseline, all participants will undergo positron emission tomography imaging with tracers targeted against Aß deposition (11C-PIB), activated glia (11C-PK11195) and synaptic vesicle glycoprotein 2A (11C-UCB-J), two brain magnetic resonance imaging scans, and extensive cognitive testing. In addition, blood samples are collected for various laboratory measurements and blood biomarker analysis and cerebrospinal fluid samples are collected from a subset of participants based on additional voluntary informed consent. To evaluate the predictive value of the early neuroimaging findings, neuropsychological evaluation and blood biomarker measurements will be repeated after a 4-year follow-up period. DISCUSSION: Results of the ASIC-E4 project will bridge the gap related to limited knowledge of the synaptic and inflammatory changes and their association with each other and Aß in "at-risk" individuals. Thorough in vivo characterization of the biomarker profiles in this population will produce valuable information for diagnostic purposes and future drug development, where the field has already started to look beyond Aß.

11.
J Sci Med Sport ; 24(12): 1255-1260, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34489177

RESUMEN

OBJECTIVES: To determine how components of accelerometer-measured sedentary behavior (SB) and physical activity (PA), and fitness are associated with insulin sensitivity in adults with metabolic syndrome. DESIGN: Cross-sectional. METHODS: Target population was middle-aged (40-65 years) sedentary adults with metabolic syndrome. SB, breaks in SB, standing, and PA were measured for four weeks with hip-worn accelerometers. VO2max (ml/min/kg) was measured with maximal cycle ergometry. Insulin sensitivity was determined by hyperinsulinaemic-euglycaemic clamp (M-value) and fasting blood sampling (HOMA-IR, insulin). Multivariable regression was used for analyses. RESULTS: Sixty-four participants (37 women; 58.3 [SD 6.8] years) were included. Participants spent 10.0 (1.0) h sedentary, 1.8 (0.6) h standing, and 2.7 (0.6) h in PA and took 5149 (1825) steps and 29 (8) breaks daily. In sex-, age- and accelerometer wear time-adjusted model SB, standing, steps and VO2max were associated with M-value (ß = -0.384; ß = 0.400; ß = 0.350; ß = 0.609, respectively), HOMA-IR (ß = 0.420; ß = -0.548; ß = -0.252; ß = -0.449), and insulin (ß = 0.433; ß = -0.541; ß = -0.252; ß = -0.453); all p-values < 0.05. Breaks associated only with M-value (ß = 0.277). When further adjusted for body fat %, only standing remained significantly associated with HOMA-IR (ß = -0.381) and insulin (ß = -0.366); significance was maintained even when further adjusted for SB, PA and fitness. Light and moderate-to-vigorous PA were not associated with insulin sensitivity. CONCLUSIONS: Standing is associated with insulin sensitivity markers. The association with HOMA-IR and insulin is independent of adiposity, PA, SB and fitness. Further studies are warranted, but these findings encourage replacing sitting with standing for potential improvements in insulin sensitivity in adults at increased type 2 diabetes risk.


Asunto(s)
Ejercicio Físico/fisiología , Resistencia a la Insulina/fisiología , Síndrome Metabólico/fisiopatología , Aptitud Física/fisiología , Conducta Sedentaria , Posición de Pie , Acelerometría , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Insulina/sangre , Masculino , Persona de Mediana Edad
12.
J Nucl Med ; 62(4): 577-583, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32817143

RESUMEN

Sialic acid-binding immunoglubulinlike lectin 9 (Siglec-9) is a ligand of vascular adhesion protein 1. A 68Ga-labeled peptide of Siglec-9, 68Ga-DOTA-Siglec-9, holds promise as a novel PET tracer for imaging of inflammation. This first-in-humans study investigated the safety, tolerability, biodistribution, and radiation dosimetry of this radiopharmaceutical. Methods: Six healthy men underwent dynamic whole-body PET/CT. Serial venous blood samples were drawn from 1 to 240 min after intravenous injection of 162 ± 4 MBq of 68Ga-DOTA-Siglec-9. In addition to γ-counting, the plasma samples were analyzed by high-performance liquid chromatography to detect intact tracer and radioactive metabolites. Radiation doses were calculated using the OLINDA/EXM software, version 2.2. In addition, a patient with early rheumatoid arthritis was studied with both 68Ga-DOTA-Siglec-9 and 18F-FDG PET/CT to determine the ability of the new tracer to detect arthritis. Results:68Ga-DOTA-Siglec-9 was well tolerated by all subjects. 68Ga-DOTA-Siglec-9 was rapidly cleared from the blood circulation, and several radioactive metabolites were detected. The organs with the highest absorbed doses were the urinary bladder wall (0.38 mSv/MBq) and kidneys (0.054 mSv/MBq). The mean effective dose was 0.022 mSv/MBq (range, 0.020-0.024 mSv/MBq). Most importantly, however, 68Ga-DOTA-Siglec-9 was comparable to 18F-FDG in detecting arthritis. Conclusion: Intravenous injection of 68Ga-DOTA-Siglec-9 was safe and biodistribution was favorable for testing of the tracer in larger group of patients with rheumatoid arthritis, as is planned for the next phase of clinical trials. The effective radiation dose of 68Ga-DOTA-Siglec-9 was within the same range as the effective radiation doses of other 68Ga-labeled tracers. Injection of 150 MBq of 68Ga-DOTA-Siglec-9 would expose a subject to 3.3 mSv. These findings support the possible repeated clinical use of 68Ga-DOTA-Siglec-9, such as in trials to elucidate the treatment efficacy of novel drug candidates.


Asunto(s)
Amina Oxidasa (conteniendo Cobre)/metabolismo , Antígenos CD/química , Moléculas de Adhesión Celular/metabolismo , Radioisótopos de Galio/química , Compuestos Heterocíclicos con 1 Anillo/química , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos/química , Radiofármacos/metabolismo , Lectinas Similares a la Inmunoglobulina de Unión a Ácido Siálico/química , Adulto , Femenino , Humanos , Ligandos , Masculino , Radiofármacos/efectos adversos , Radiofármacos/farmacocinética , Seguridad , Solubilidad , Distribución Tisular
13.
Stud Health Technol Inform ; 264: 1550-1551, 2019 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-31438226

RESUMEN

We report on the pilot evaluation of an experimental query-based search functionality that enables phrase-level query rewriting in an unsupervised way. It is intended for supporting search in clinical text. Qualitative evaluation is done by three clinicans using a prototype search tool. They report that they find the tested search functionality to be beneficial for making query-based searching in clinical text more efficient.


Asunto(s)
Procesamiento de Lenguaje Natural , Motor de Búsqueda , Escritura
14.
Physiol Rep ; 7(3): e13980, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30740933

RESUMEN

The effects of sprint interval training (SIT) on intramyocellular (IMCL) and extramyocellular (EMCL) lipid accumulation are unclear. We tested the effects of SIT and moderate-intensity continuous training (MICT) on IMCL and EMCL accumulation in a randomized controlled setting in two different study populations; healthy untrained men (n 28) and subjects with type 2 diabetes (T2D) or prediabetes (n 26). Proton magnetic resonance spectroscopy (1 H MRS) was used to determine IMCL and EMCL in the Tibialis anterior muscle (TA) before and after a 2-week exercise period. The exercise period comprised six sessions of SIT or MICT cycling on a cycle ergometer. IMCL increased after SIT compared to MICT (P = 0.042) in both healthy and T2D/prediabetic subjects. On EMCL the training intervention had no significant effect. In conclusion, IMCL serves as an important energy depot during exercise and can be extended by high intensity exercise. The effects of high intensity interval exercise on IMCL seem to be similar regardless of insulin sensitivity or the presence of T2D.


Asunto(s)
Ciclismo , Diabetes Mellitus Tipo 2/terapia , Entrenamiento de Intervalos de Alta Intensidad , Metabolismo de los Lípidos , Músculo Esquelético/metabolismo , Estado Prediabético/terapia , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/metabolismo , Finlandia , Humanos , Resistencia a la Insulina , Masculino , Persona de Mediana Edad , Consumo de Oxígeno , Estado Prediabético/diagnóstico , Estado Prediabético/metabolismo , Factores de Tiempo , Resultado del Tratamiento
15.
Diabetologia ; 61(8): 1817-1828, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29717337

RESUMEN

AIMS/HYPOTHESIS: Pancreatic fat accumulation may contribute to the development of beta cell dysfunction. Exercise training improves whole-body insulin sensitivity, but its effects on pancreatic fat content and beta cell dysfunction are unclear. The aim of this parallel-group randomised controlled trial was to evaluate the effects of exercise training on pancreatic fat and beta cell function in healthy and prediabetic or type 2 diabetic participants and to test whether the responses were similar regardless of baseline glucose tolerance. METHODS: Using newspaper announcements, a total of 97 sedentary 40-55-year-old individuals were assessed for eligibility. Prediabetes (impaired fasting glucose and/or impaired glucose tolerance) and type 2 diabetes were defined by ADA criteria. Of the screened candidates, 28 healthy men and 26 prediabetic or type 2 diabetic men and women met the inclusion criteria and were randomised into 2-week-long sprint interval or moderate-intensity continuous training programmes in a 1:1 allocation ratio using random permuted blocks. The primary outcome was pancreatic fat, which was measured by magnetic resonance spectroscopy. As secondary outcomes, beta cell function was studied using variables derived from OGTT, and whole-body insulin sensitivity and pancreatic fatty acid and glucose uptake were measured using positron emission tomography. The measurements were carried out at the Turku PET Centre, Finland. The analyses were based on an intention-to-treat principle. Given the nature of the intervention, blinding was not applicable. RESULTS: At baseline, the group of prediabetic or type 2 diabetic men had a higher pancreatic fat content and impaired beta cell function compared with the healthy men, while glucose and fatty acid uptake into the pancreas was similar. Exercise training decreased pancreatic fat similarly in healthy (from 4.4% [3.0%, 6.1%] to 3.6% [2.4%, 5.2%] [mean, 95% CI]) and prediabetic or type 2 diabetic men (from 8.7% [6.0%, 11.9%] to 6.7% [4.4%, 9.6%]; p = 0.036 for time effect) without any changes in pancreatic substrate uptake (p ≥ 0.31 for time effect in both insulin-stimulated glucose and fasting state fatty acid uptake). In prediabetic or type 2 diabetic men and women, both exercise modes similarly improved variables describing beta cell function. CONCLUSIONS/INTERPRETATION: Two weeks of exercise training improves beta cell function in prediabetic or type 2 diabetic individuals and decreases pancreatic fat regardless of baseline glucose tolerance. This study shows that short-term training efficiently reduces ectopic fat within the pancreas, and exercise training may therefore reduce the risk of type 2 diabetes. TRIAL REGISTRATION: ClinicalTrials.gov NCT01344928 FUNDING: This study was funded by the Emil Aaltonen Foundation, the European Foundation for the Study of Diabetes, the Finnish Diabetes Foundation, the Orion Research Foundation, the Academy of Finland (grants 251399, 256470, 281440, and 283319), the Ministry of Education of the State of Finland, the Paavo Nurmi Foundation, the Novo Nordisk Foundation, the Finnish Cultural Foundation, the Hospital District of Southwest Finland, the Turku University Foundation, and the Finnish Medical Foundation.


Asunto(s)
Tejido Adiposo , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Ejercicio Físico/fisiología , Resistencia a la Insulina , Estado Prediabético/metabolismo , Adulto , Antropometría , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , Células Secretoras de Insulina/metabolismo , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Páncreas/metabolismo , Resultado del Tratamiento
16.
Stud Health Technol Inform ; 247: 725-729, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29678056

RESUMEN

We report on the development and evaluation of a prototype tool aimed to assist laymen/patients in understanding the content of clinical narratives. The tool relies largely on unsupervised machine learning applied to two large corpora of unlabeled text - a clinical corpus and a general domain corpus. A joint semantic word-space model is created for the purpose of extracting easier to understand alternatives for words considered difficult to understand by laymen. Two domain experts evaluate the tool and inter-rater agreement is calculated. When having the tool suggest ten alternatives to each difficult word, it suggests acceptable lay words for 55.51% of them. This and future manual evaluation will serve to further improve performance, where also supervised machine learning will be used.


Asunto(s)
Comprensión , Narración , Procesamiento de Lenguaje Natural , Semántica , Humanos , Aprendizaje Automático Supervisado , Aprendizaje Automático no Supervisado
17.
Med Sci Sports Exerc ; 50(1): 18-27, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28857909

RESUMEN

INTRODUCTION: The aim of this study was to investigate affective responses to repeated sessions of sprint interval training (SIT) in comparison with moderate-intensity continuous training (MICT) in insulin-resistant subjects. METHODS: Twenty-six insulin-resistant adults (age, 49 (4) yr; 10 women) were randomized into SIT (n = 13) or MICT (n = 13) groups. Subjects completed six supervised training sessions within 2 wk (SIT session, 4-6 × 30 s all-out cycling/4-min recovery; MICT session, 40-60 min at 60% peak work load). Perceived exertion, stress, and affective state were assessed with questionnaires before, during and after each training session. RESULTS: Perceived exertion, displeasure, and arousal were higher during the SIT compared with MICT sessions (all P < 0.01). These, however, alleviated similarly in response to SIT and MICT over the 6 d of training (all P < 0.05). SIT versus MICT exercise increased perceived stress and decreased positive affect and feeling of satisfaction acutely after exercise especially in the beginning of the intervention (all P < 0.05). These negative responses declined significantly during the training period: perceived stress and positive activation were no longer different between the training groups after the third, and satisfaction after the fifth training session (P > 0.05). CONCLUSIONS: The perceptual and affective responses are more negative both during and acutely after SIT compared with MICT in untrained insulin-resistant adults. These responses, however, show significant improvements already within six training sessions, indicating rapid positive affective and physiological adaptations to continual exercise training, both SIT and MICT. These findings suggest that even very intense SIT is mentally tolerable alternative for untrained people with insulin resistance.


Asunto(s)
Adaptación Fisiológica , Entrenamiento de Intervalos de Alta Intensidad/métodos , Resistencia a la Insulina , Afecto , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Satisfacción Personal , Esfuerzo Físico , Estrés Psicológico , Encuestas y Cuestionarios
18.
Sci Rep ; 7(1): 10531, 2017 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-28874821

RESUMEN

Type 2 diabetes mellitus (T2DM) is associated with reduced myocardial glucose uptake (GU) and increased free fatty acid uptake (FFAU). Sprint interval training (SIT) improves physical exercise capacity and metabolic biomarkers, but effects of SIT on cardiac function and energy substrate metabolism in diabetic subjects are unknown. We tested the hypothesis that SIT is more effective than moderate-intensity continuous training (MICT) on adaptations in left and right ventricle (LV and RV) glucose and fatty acid metabolism in diabetic subjects. Twenty-six untrained men and women with T2DM or prediabetes were randomized into two-week-long SIT (n = 13) and MICT (n = 13) interventions. Insulin-stimulated myocardial GU and fasted state FFAU were measured by positron emission tomography and changes in LV and RV structure and function by cardiac magnetic resonance. In contrast to our hypothesis, SIT significantly decreased GU compared to MICT in LV. FFAU of both ventricles remained unchanged by training. RV end-diastolic volume (EDV) and RV mass increased only after MICT, whereas LV EDV, LV mass, and RV and LV end-systolic volumes increased similarly after both training modes. As SIT decreases myocardial insulin-stimulated GU compared to MICT which may already be reduced in T2DM, SIT may be metabolically less beneficial than MICT for a diabetic heart.


Asunto(s)
Diabetes Mellitus Tipo 2/fisiopatología , Terapia por Ejercicio/métodos , Fluorodesoxiglucosa F18/farmacocinética , Ventrículos Cardíacos/diagnóstico por imagen , Acondicionamiento Físico Humano/métodos , Estado Prediabético/fisiopatología , Radiofármacos/farmacocinética , Adulto , Diabetes Mellitus Tipo 2/diagnóstico por imagen , Diabetes Mellitus Tipo 2/terapia , Terapia por Ejercicio/efectos adversos , Femenino , Ventrículos Cardíacos/metabolismo , Humanos , Insulina/sangre , Masculino , Persona de Mediana Edad , Consumo de Oxígeno , Acondicionamiento Físico Humano/efectos adversos , Tomografía de Emisión de Positrones , Estado Prediabético/diagnóstico por imagen , Estado Prediabético/terapia , Función Ventricular
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