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Boyce A.M.,Eunice Kennedy Shriver National Institute of Child Health and Human Development | Gafni R.I.,National Institute of Dental and Craniofacial Research
Journal of Clinical Endocrinology and Metabolism | Year: 2011

Evaluation of the child with fractures is challenging, as no clear guidelines exist to distinguish traumatic from pathological fractures. Although most fractures in childhood are benign, recurrent fractures may be associated with a wide variety of primary skeletal diseases as well as secondary causes, necessitating a careful history and physical exam to guide the evaluation. There is no "gold standard" for the evaluation and treatment of children with fractures and low bone mineral density (BMD); therefore, the diagnosis of osteoporosis in a pediatric patient should be made using a combination of clinical and radiographic features. Interpretation of bone densitometry in growing patients presents a unique set of challenges because areal BMD measured by dual-energy x-ray absorptiometry depends on multiple dynamic variables. Interpretation of pediatric dual-energy x-ray absorptiometry should be based on Z-scores (SD scores compared to age, sex, and ethnicity-matched controls), using normative databases specific to the brand of densitometer and the patient population. Given the skeleton's ability to recover from low BMD through modeling and remodeling, optimizing management of underlying conditions leading to bone fragility is the initial step. Conservative measures including calcium and vitamin D supplementation and weight-bearing physical activity are important interventions that should not be overlooked. The use of bisphosphonates in children and adolescents is controversial due to lack of long-term efficacy and safety data and should be limited to clinical trials and compassionate therapy in children with significantly compromised quality of life. Close monitoring is required, and further study is necessary to assess their long-term safety and efficacy in children. Copyright © 2011 by The Endocrine Society. Source

Collins M.T.,National Institute of Dental and Craniofacial Research | Singer F.R.,John Wayne Cancer Institute | Eugster E.,Indiana University
Orphanet Journal of Rare Diseases | Year: 2012

Fibrous dysplasia (FD) is sometimes accompanied by extraskeletal manifestations that can include any combination of café-au-lait macules, hyperfunctioning endocrinopathies, such as gonadotropin-independent precocious puberty, hyperthyroidism, growth hormone excess, FGF23-mediated renal phosphate wasting, and/or Cushing syndrome, as well as other less common features. The combination of any of these findings, with or without FD, is known as McCune-Albright syndrome (MAS). The broad spectrum of involved tissues and the unpredictable combination of findings owe to the fact that molecular defect is due to dominant activating mutations in the widely expressed signaling protein, G s, and the fact these mutations arises sporadically, often times early in development, prior to gastrulation, and can distribute across many or few tissues. The complexity can be mastered by a systematic screening of potentially involved tissues and cognizance that the pattern of involved tissues is established, to some degree, in utero. Thorough testing allows the clinician to establish, often times at presentation, the full extent of the disease, and importantly as well what tissues are unaffected. Treatment and follow-up can then be focused on affected systems and a meaningful prognosis can be offered to the patient and family. The authors outline screening and treatment strategies that allow for effective management of the extraskeletal manifestations of FD. © 2012 Collins et al; licensee BioMed Central Ltd. Source

Lumelsky N.,National Institute of Dental and Craniofacial Research
Cell Metabolism | Year: 2014

Obtaining large numbers of functional pancreatic islets via direct cellular reprogramming is an important clinically relevant goal. In a recent issue of Cell Stem Cell, Li et al. (2014) report a new step-wise protocol for generating islet cells from mouse embryonic fibroblasts using a combination of soluble molecules. © 2014 Elsevier Inc. Source

Kariko K.,University of Pennsylvania | Muramatsu H.,University of Pennsylvania | Keller J.M.,National Institute of Dental and Craniofacial Research | Weissman D.,University of Pennsylvania
Molecular Therapy | Year: 2012

Advances in the optimization of in vitro-transcribed mRNA are bringing mRNA-mediated therapy closer to reality. In cultured cells, we recently achieved high levels of translation with high-performance liquid chromatography (HPLC)-purified, in vitro-transcribed mRNAs containing the modified nucleoside pseudouridine. Importantly, pseudouridine rendered the mRNA non-immunogenic. Here, using erythropoietin (EPO)-encoding mRNA complexed with TransIT-mRNA, we evaluated this new generation of mRNA in vivo. A single injection of 100 ng (0.005 mg/kg) mRNA elevated serum EPO levels in mice significantly by 6 hours and levels were maintained for 4 days. In comparison, mRNA containing uridine produced 10-100-fold lower levels of EPO lasting only 1 day. EPO translated from pseudouridine-mRNA was functional and caused a significant increase of both reticulocyte counts and hematocrits. As little as 10 ng mRNA doubled reticulocyte numbers. Weekly injection of 100 ng of EPO mRNA was sufficient to increase the hematocrit from 43 to 57%, which was maintained with continued treatment. Even when a large amount of pseudouridine-mRNA was injected, no inflammatory cytokines were detectable in plasma. Using macaques, we could also detect significantly-increased serum EPO levels following intraperitoneal injection of rhesus EPO mRNA. These results demonstrate that HPLC-purified, pseudouridine-containing mRNAs encoding therapeutic proteins have great potential for clinical applications. © The American Society of Gene & Cell Therapy. Source

Chen W.,National Institute of Dental and Craniofacial Research | Konkel J.E.,National Institute of Dental and Craniofacial Research
Journal of Molecular Cell Biology | Year: 2010

In näive T cells transforming growth factor-beta (TGF-β) induces Foxp3, a transcription factor essential for programming and developing T regulatory cells (Treg cells). This finding reveals a physiological factor which can turn on the Foxp3 gene and establishes an experimental approach to induce antigen-specific Treg cells as a potential therapy for human diseases. While this role for TGF-β is well confirmed, several critical questions remain largely unanswered and await further investigation. In this regard, it is imperative to understand the molecular pathways by which TGF-β signaling initiates and regulates Foxp3 expression. It is also important to elucidate which factors and/or cytokines influence the TGF-β-mediated conversion of näive T cells and how to create an immunologically regulatory milieu to facilitate Treg cell generation in vivo. In this short article, we will highlight the key findings and recent progress in the field, discuss the molecular mechanisms underlying the TGF-β-mediated induction of Foxp3, and attempt to outline the challenges ahead. Source

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