34 research outputs found
Detailed prenatal and postnatal MRI findings and clinical analysis of RAF1 in Noonan syndrome
Noonan syndrome is a genetically heterogeneous developmental disorder, which usually includes findings such as short stature, facial dysmorphia, cardiac abnormalities and a varying degree of intellectual disability. We present a unique case of a rare variant of Noonan syndrome in a very preterm female infant born at 28Â +Â 4 gestational weeks, with abnormal radiological findings visible at fetal magnetic resonance imaging (MRI) and evolution of the brain lesions during infancy
In Vivo and In Vitro Study of a Polylactide-Fiber-Reinforced β-Tricalcium Phosphate Composite Cage in an Ovine Anterior Cervical Intercorporal Fusion Model
A poly-70L/30DL-lactide (PLA70)âβ-tricalcium phosphate (β-TCP) composite implant reinforced by continuous PLA-96L/4D-lactide (PLA96) fibers was designed for in vivo spinal fusion. The pilot study was performed with four sheep, using titanium cage implants as controls. The composite implants failed to direct bone growth as desired, whereas the bone contact and the proper integration were evident with controls 6 months after implantation. Therefore, the PLA70/β-TCP composite matrix material was further analyzed in the in vitro experiment by human and ovine adipose stem cells (hASCs and oASCs). The composites proved to be biocompatible as confirmed by live/dead assay. The proliferation rate of oASCs was higher than that of hASCs at all times during the 28âd culture period. Furthermore, the composites had only a minor osteogenic effect on oASCs, whereas the hASC osteogenesis on PLA70/β-TCP composites was evident. In conclusion, the composite implant material can be applied with hASCs for tissue engineering but not be evaluated in vivo with sheep
Iron Overload in Allogeneic Hematopoietic Cell Transplantation Outcome: A Meta-Analysis
AbstractAn elevated ferritin level before allogeneic hematopoietic cell transplantation (HCT) is an adverse prognostic factor for overall survival (OS) and nonrelapse mortality. Because ferritin is an imperfect surrogate of iron stores, the prognostic role of iron overload remains unclear. We conducted a patient-level meta-analysis of 4Â studies that used magnetic resonance imaging to estimate pre-HCT liver iron content (LIC). An elevated LIC was not associated with a significant increase in mortality: the hazard ratio (HR) for mortality associated with LICÂ >Â 7Â mg/g dry weight (primary endpoint) was 1.4 (PÂ = .18). In contrast, ferritin >1000Â ng/mL was a significant prognostic factor (HR for mortality, 1.7; PÂ = .036). There was, however, no significant association between ferritin > 2500 and mortality. This meta-analysis suggests that iron overload, as assessed by LIC, is not a strong prognostic factor for OS in a general adult HCT population. Our data also suggest that ferritin is an inadequate surrogate for iron overload in HCT
Human Bone Marrow Adipose Tissue is a Metabolically Active and Insulin-Sensitive Distinct Fat Depot
ContextBone marrow (BM) in adult long bones is rich in adipose tissue, but the functions of BM adipocytes are largely unknown. We set out to elucidate the metabolic and molecular characteristics of BM adipose tissue (BMAT) in humans.ObjectiveOur aim was to determine if BMAT is an insulin-sensitive tissue, and whether the insulin sensitivity is altered in obesity or type 2 diabetes (T2DM).DesignThis was a cross-sectional and longitudinal study.SettingThe study was conducted in a clinical research center.Patients or Other ParticipantsBone marrow adipose tissue glucose uptake (GU) was assessed in 23 morbidly obese subjects (9 with T2DM) and 9 healthy controls with normal body weight. In addition, GU was assessed in another 11 controls during cold exposure. Bone marrow adipose tissue samples for molecular analyses were collected from non-DM patients undergoing knee arthroplasty.Intervention(s)Obese subjects were assessed before and 6 months after bariatric surgery and controls at 1 time point.Main Outcome MeasureWe used positron emission tomography imaging with 2-[18F]fluoro-2-deoxy-D-glucose tracer to characterize GU in femoral and vertebral BMAT. Bone marrow adipose tissue molecular profile was assessed using quantitative RT-PCR.ResultsInsulin enhances GU in human BMAT. Femoral BMAT insulin sensitivity was impaired in obese patients with T2DM compared to controls, but it improved after bariatric surgery. Furthermore, gene expression analysis revealed that BMAT was distinct from brown and white adipose tissue.ConclusionsBone marrow adipose tissue is a metabolically active, insulin-sensitive and molecularly distinct fat depot that may play a role in whole body energy metabolism.</p
Effects of short-term sprint interval and moderate-intensity continuous training on liver fat content, lipoprotein profile, and substrate uptake: a randomized trial
Type 2 diabetes (T2D) and increased liver fat content (LFC) alter lipoprotein profile and composition and impair liver substrate uptake. Exercise training mitigates T2D and reduces LFC, but the benefits of different training intensities in terms of lipoprotein classes and liver substrate uptake are unclear. The aim of this study was to evaluate the effects of moderate-intensity continuous training (MICT) or sprint interval training (SIT) on LFC, liver substrate uptake, and lipoprotein profile in subjects with normoglycemia or prediabetes/T2D. We randomized 54 subjects (normoglycemic group, n = 28; group with prediabetes/T2D, n = 26; age = 40-55 yr) to perform either MICT or SIT for 2 wk and measured LFC with magnetic resonance spectroscopy, lipoprotein composition with NMR, and liver glucose uptake (GU) and fatty acid uptake (FAU) using PET. At baseline, the group with prediabetes/T2D had higher LFC, impaired lipoprotein profile, and lower whole body insulin sensitivity and aerobic capacity compared with the normoglycemic group. Both training modes improved aerobic capacity (P 5.6%; low LFC, NEW & NOTEWORTHY: In the short term, both sprint interval training and moderate-intensity continuous training (MICT) reduce liver fat content and improve lipoprotein profile; however, MICT seems to be preferable in improving liver insulin sensitivity.</div
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Decreased insulinâstimulated brown adipose tissue glucose uptake after shortâterm exercise training in healthy middleâaged men
Aims To test the hypothesis that highâintensity interval training (HIIT) and moderateâintensity continuous training (MICT) improve brown adipose tissue (BAT) insulin sensitivity. Participants and methods Healthy middleâaged men (n = 18, age 47 years [95% confidence interval {CI} 49, 43], body mass index 25.3 kg/m2 [95% CI 24.1â26.3], peak oxygen uptake (VO2peak) 34.8 mL/kg/min [95% CI 32.1, 37.4] ) were recruited and randomized into six HIIT or MICT sessions within 2 weeks. Insulinâstimulated glucose uptake was measured using 2â[18F]flouroâ2âdeoxyâDâglucose positronâemission tomography in BAT, skeletal muscle, and abdominal and femoral subcutaneous and visceral white adipose tissue (WAT) depots before and after the training interventions. Results: Training improved VO2peak (P = .0005), insulinâstimulated glucose uptake into the quadriceps femoris muscle (P = .0009) and femoral subcutaneous WAT (P = .02) but not into BAT, with no difference between the training modes. Using preâintervention BAT glucose uptake, we next stratified subjects into high BAT (>2.9 Âľmol/100 g/min; n = 6) or low BAT (<2.9 Âľmol/100 g/min; n = 12) groups. Interestingly, training decreased insulinâstimulated BAT glucose uptake in the high BAT group (4.0 [2.8, 5.5] vs 2.5 [1.7, 3.6]; training*BAT, P = .02), whereas there was no effect of training in the low BAT group (1.5 [1.2, 1.9] vs 1.6 [1.2, 2.0] Âľmol/100 g/min). Participants in the high BAT group had lower levels of inflammatory markers compared with those in the low BAT group. Conclusions: Participants with functionally active BAT have an improved metabolic profile compared with those with low BAT activity. Shortâterm exercise training decreased insulinâstimulated BAT glucose uptake in participants with active BAT, suggesting that training does not work as a potent stimulus for BAT activation
Dopamine and Opioid Neurotransmission in Behavioral Addictions: A Comparative PET Study in Pathological Gambling and Binge Eating.
Although behavioral addictions share many clinical features with drug addictions, they show strikingly large variation in their behavioral phenotypes (such as in uncontrollable gambling or eating). Neurotransmitter function in behavioral addictions is poorly understood, but has important implications in understanding its relationship with substance use disorders and underlying mechanisms of therapeutic efficacy. Here, we compare opioid and dopamine function between two behavioral addiction phenotypes: pathological gambling (PG) and binge eating disorder (BED). Thirty-nine participants (15 PG, 7 BED, and 17 controls) were scanned with [11C]carfentanil and [18F]fluorodopa positron emission tomography using a high-resolution scanner. Binding potentials relative to non-displaceable binding (BPND) for [11C]carfentanil and influx rate constant (Ki) values for [18F]fluorodopa were analyzed with region-of-interest and whole-brain voxel-by-voxel analyses. BED subjects showed widespread reductions in [11C]carfentanil BPND in multiple subcortical and cortical brain regions and in striatal [18F]fluorodopa Ki compared with controls. In PG patients, [11C]carfentanil BPND was reduced in the anterior cingulate with no differences in [18F]fluorodopa Ki compared with controls. In the nucleus accumbens, a key region involved in reward processing, [11C]Carfentanil BPND was 30-34% lower and [18F]fluorodopa Ki was 20% lower in BED compared with PG and controls (p<0.002). BED and PG are thus dissociable as a function of dopaminergic and opioidergic neurotransmission. Compared with PG, BED patients show widespread losses of mu-opioid receptor availability together with presynaptic dopaminergic defects. These findings highlight the heterogeneity underlying the subtypes of addiction and indicate differential mechanisms in the expression of pathological behaviors and responses to treatment.This study was supported by the Academy of Finland (grant #256836), the Finnish Medical Foundation, the Finnish Alcohol Research Foundation and the Turku University Central Hospital (EVO grants). VV was supported by a Wellcome Trust Fellowship (093705/10/Z)
Brain volumes and white matter microstructure in 8- to 10-year-old children born with fetal growth restriction
Abstract
Background: Fetal growth restriction caused by placental insufficiency is associated with increased risk of poor neurodevelopment, even in the absence of specific perinatal brain injury. Placental insufficiency leads to chronic hypoxaemia that may alter cerebral tissue organisation and maturation.
Objective: The aim of this study was to assess the effects fetal growth restriction and fetal haemodynamic abnormalities have on brain volumes and white matter microstructure at early school age.
Materials and methods: This study examined 32 children born with fetal growth restriction at 24 to 40 gestational weeks, and 27 gestational age-matched children, who were appropriate for gestational age. All children underwent magnetic resonance imaging (MRI) at the age of 8â10 years. Cerebral volumes were analysed, and tract-based spatial statistics and atlas-based analysis of white matter were performed on 17 children born with fetal growth restriction and 14 children with birth weight appropriate for gestational age.
Results: Children born with fetal growth restriction demonstrated smaller total intracranial volumes compared to children with normal fetal growth, whereas no significant differences in grey or white matter volumes were detected. On atlas-based analysis of white matter, children born with fetal growth restriction demonstrated higher mean and radial diffusivity values in large white matter tracts when compared to children with normal fetal growth.
Conclusion: Children ages 8â10 years old born with fetal growth restriction demonstrated significant changes in white matter microstructure compared to children who were appropriate for gestational age, even though no differences in grey and white matter volumes were detected. Poor fetal growth may impact white matter maturation and lead to neurodevelopmental impairment later in life
Obesity Is Associated with Decreased Âľ-Opioid But Unaltered Dopamine D2 Receptor Availability in the Brain
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