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Diabetes type I is associated with bone loss and increased bone adiposity. Osteoblasts and adipocytes are both derived from mesenchymal stem cells located in the bone marrow, therefore we hypothesized that if we could block adipocyte differentiation we might prevent bone loss in diabetic mice. Control and insulin-deficient diabetic BALB/c mice were chronically treated with a peroxisomal proliferator-activated receptor gamma (PPARgamma) antagonist, bisphenol-A-diglycidyl ether (BADGE), to block adipocyte differentiation. Effects on bone density, adiposity, and gene expression were measured. BADGE treatment did not prevent diabetes-associated hyperglycemia or weight loss, but did prevent diabetes-induced hyperlipidemia and effectively blocked diabetes type I-induced bone adiposity. Despite this, BADGE treatment did not prevent diabetes type I suppression of osteoblast markers (runx2 and osteocalcin) and bone loss (as determined by micro-computed tomography). BADGE did not suppress osteoblast gene expression or bone mineral density in control mice, however, chronic (but not acute) BADGE treatment did suppress osteocalcin expression in osteoblasts in vitro. Taken together, our findings suggest that BADGE treatment is an effective approach to reduce serum triglyceride and free fatty acid levels as well as bone adiposity associated with type I diabetes. The inability of BADGE treatment to prevent bone loss in diabetic mice suggests that marrow adiposity is not linked to bone density status in type I diabetes, but we cannot exclude the possibility of additional BADGE effects on osteoblasts or other bone cells, which could contribute to preventing the rescue of the bone phenotype.  相似文献   
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Autism spectrum disorders (ASDs), which include the prototypic autistic disorder (AD), Asperger’s syndrome (AS) and pervasive developmental disorders not otherwise specified (PDD‐NOS), are complex neurodevelopmental conditions of unknown aetiology. The current study investigated the metabolites in the methionine cycle, the transsulphuration pathway, folate, vitamin B12 and the C677T polymorphism of the MTHFR gene in three groups of children diagnosed with AD (n= 15), AS (n= 5) and PDD‐NOS (n= 19) and their age‐ and sex‐matched controls (n= 25). No metabolic disturbances were seen in the AS patients, while in the AD and PDD‐NOS groups, lower plasma levels of methionine (P= 0.01 and P= 0.03, respectively) and α‐aminobutyrate were observed (P= 0.01 and P= 0.001, respectively). Only in the AD group, plasma cysteine (P= 0.02) and total blood glutathione (P= 0.02) were found to be reduced. Although there was a trend towards lower levels of serine, glycine, N, N‐dimethylglycine in AD patients, the plasma levels of these metabolites as well as the levels of homocysteine and cystathionine were not statistically different in any of the ASDs groups. The serum levels of vitamin B12 and folate were in the normal range. The results of the MTHFR gene analysis showed a normal distribution of the C677T polymorphism in children with ASDs, but the frequency of the 677T allele was slightly more prevalent in AD patients. Our study indicates a possible role for the alterations in one carbon metabolism in the pathophysiology of ASDs and provides, for the first time, preliminary evidence for metabolic and genetic differences between clinical subtypes of ASDs.  相似文献   
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Cristofor  Sergiu  Vadineanu  Angheluta  Sarbu  Anca  Postolache  Carmen  Dobre  Roxana  Adamescu  Mihai 《Hydrobiologia》2003,506(1-3):625-634
Hydrobiologia - Transition towards hypertrophy has affected biodiversity and productivity of most aquatic and wetland systems in the Lower Danube Wetland System (LDWS) over the last two decades....  相似文献   
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Monogenic neurodevelopmental disorders provide key insights into the pathogenesis of disease and help us understand how specific genes control the development of the human brain. Timothy syndrome is caused by a missense mutation in the L-type calcium channel Ca(v)1.2 that is associated with developmental delay and autism. We generated cortical neuronal precursor cells and neurons from induced pluripotent stem cells derived from individuals with Timothy syndrome. Cells from these individuals have defects in calcium (Ca(2+)) signaling and activity-dependent gene expression. They also show abnormalities in differentiation, including decreased expression of genes that are expressed in lower cortical layers and in callosal projection neurons. In addition, neurons derived from individuals with Timothy syndrome show abnormal expression of tyrosine hydroxylase and increased production of norepinephrine and dopamine. This phenotype can be reversed by treatment with roscovitine, a cyclin-dependent kinase inhibitor and atypical L-type-channel blocker. These findings provide strong evidence that Ca(v)1.2 regulates the differentiation of cortical neurons in humans and offer new insights into the causes of autism in individuals with Timothy syndrome.  相似文献   
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Ultrasound segmentation is a challenging problem due to the inherent speckle and some artifacts like shadows, attenuation and signal dropout. Existing methods need to include strong priors like shape priors or analytical intensity models to succeed in the segmentation. However, such priors tend to limit these methods to a specific target or imaging settings, and they are not always applicable to pathological cases. This work introduces a semi-supervised segmentation framework for ultrasound imaging that alleviates the limitation of fully automatic segmentation, that is, it is applicable to any kind of target and imaging settings. Our methodology uses a graph of image patches to represent the ultrasound image and user-assisted initialization with labels, which acts as soft priors. The segmentation problem is formulated as a continuous minimum cut problem and solved with an efficient optimization algorithm. We validate our segmentation framework on clinical ultrasound imaging (prostate, fetus, and tumors of the liver and eye). We obtain high similarity agreement with the ground truth provided by medical expert delineations in all applications (94% DICE values in average) and the proposed algorithm performs favorably with the literature.  相似文献   
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Background aimsSpinal cord injury (SCI) represents a devastating condition leading to severe disability related to motor, sensory and autonomic dysfunction. Stem cell transplantation is considered a potential emerging therapy to stimulate neuroplastic and neuroregenerative processes after SCI. In this clinical trial, the authors investigated the safety and clinical recovery effects of intrathecal infusion of expanded Wharton jelly mesenchymal stromal cells (WJ-MSCs) in chronic complete SCI patients.MethodsThe authors designed a randomized, double-blind, crossover, placebo-controlled, phase 1/2a clinical trial (NCT03003364). Participants were 10 patients (7 males, 3 females, age range, 25–47 years) with chronic complete SCI (American Spinal Injury Association A) at dorsal level (T3-11). Patients were randomly assigned to receive a single dose of intrathecal ex vivo-expanded WJ-MSCs (10 × 106 cells) from human umbilical cord or placebo and were then switched to the other arm at 6 months. Clinical evaluation (American Spinal Injury Association impairment scale motor and sensory score, spasticity, neuropathic pain, electrical perception and pain thresholds), lower limb motor evoked potentials (MEPs) and sensory evoked potentials (SEPs), Spinal Cord Independence Measure and World Health Organization Quality of Life Brief Version were assessed at baseline, 1 month, 3 months and 6 months after each intervention. Urodynamic studies and urinary-specific quality of life (Qualiveen questionnaire) as well as anorectal manometry, functional assessment of bowel dysfunction (Rome III diagnostic questionnaire) and severity of fecal incontinence (Wexner score) were conducted at baseline and at 6 months after each intervention.ResultsIntrathecal transplantation of WJ-MSCs was considered safe, with no significant side effects. Following MSC infusion, the authors found significant improvement in pinprick sensation in the dermatomes below the level of injury compared with placebo. Other clinically relevant effects, such as an increase in bladder maximum capacity and compliance and a decrease in bladder neurogenic hyperactivity and external sphincter dyssynergy, were observed only at the individual level. No changes in motor function, spasticity, MEPs, SEPs, bowel function, quality of life or independence measures were observed.ConclusionsIntrathecal transplantation of human umbilical cord-derived WJ-MSCs is a safe intervention. A single intrathecal infusion of WJ-MSCs in patients with chronic complete SCI induced sensory improvement in the segments adjacent to the injury site.  相似文献   
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