Osteogenesis of Adipose-Derived Stem Cells

Current treatment options for skeletal repair, including immobilization, rigid fixation, alloplastic materials and bone grafts, have significant limitations. Bone tissue engineering offers a promising method for the repair of bone deficieny caused by fractures, bone loss and tumors. The use of adipose derived stem cells （ASCs） has received attention because of the self-renewal ability, high proliferative capacity and potential of osteogenic differentiation in vitro and in vivo studies of bone regeneration. Although cell therapies using ASCs are widely promising in various clinical fields, no large human clinical trials exist for bone tissue engineering. The aim of this review is to introduce how they are harvested, examine the characterization of ASCs, to review the mechanisms of osteogenic differentiation, to analyze the effect of mechanical and chemical stimuli on ASC osteodifferentiation, to summarize the current knowledge about usage of ASC in vivo studies and clinical trials, and finally to conclude with a general summary of the field and comments on its future direction.

DAPT Enhances the Apoptosis of Human Tongue Carcinoma Cells

Aim To investigate the effect of DAPT （γ-secretase inhibitor） on the growth of human tongue carcinoma cells and to determine the molecular mechanism to enable the potential application of DAPT to the treatment of tongue carcinoma. Methodology Human tongue carcinoma Tca8113 cells were cultured with DAPT. Cell growth was determined using Indigotic Reduction method. The cell cycle and apoptosis were analyzed by flow cytometry. Real-time PCR and Immuno-Fluorescence （IF） were employed to determine the intracellular expression levels. Results DAPT inhibited the growth of human tongue carcinoma Tca8113 cells by inducing G0-G1 cell cycle arrest and apoptosis, The mRNA levels of Hairy/Enhancer of Split-1 （Hes-1）, a target of Notch activation, were reduced by DAPT in a dose-dependent manner. Coincident with this observation, DAPT induced a dose-dependent promotion of constitutive Caspase-3 in Tca8113 cells. Conclusion DAPT may have a therapeutic value for human tongue carcinoma. Moreover, the effects of DAPT in tumor inhibition may arise partly via the modulation of Notch- 1 and Caspase-3.

Comparison of Effects of Mechanical Stretching on Osteogenic Potential of ASCs and BMSCs

Mechanical forces play critical roles in the development and remodeling processes of bone. As an alternative cell source for bone engineering, adipose-derived stem cells （ASCs） should be fully investigated for their responses to mechanical stress. Similarly, the osteogenic potential, stimulated by mechanical stress, should be compared with bone marrow stromal cells （BMSCs）, which have been clinically used for bone tissue engineering. In this study, ASCs and BMSCs were osteogenic-induced for 48 hours, and then subjected to uniaxial mechanical stretching for 2 or 6 hours. Cell orientation, osteogenic regulatory genes, osteogenic genes and ALP activities were measured and compared between ASCs and BMSCs. ASCs could align in a perpendicular way to the direction of stretching stress, while BMSCs did not present a specific alignment. Both 2 and 6 hours mechanical stretching could enhance the mRNA expression of Osx and Runx2 in BMSCs and ASCs, while OCN mRNA only increased in ASCs after 6 hours mechanical loading. Mechanical stretching enhanced the BMP-2 mRNA expression in ASCs, while only after 6 hours of mechanical loading significantly increased the BMP-2 gene expression in BMSCs. Significant differences only exist between ASCs and BMSCs loaded at 2 hours of mechanical stretching. It is concluded that ASCs are more rapid responders to mechanical stress, and have greater potential than BMSCs in osteogenesis when stimulated by mechanical stretching, indicating their usefulness for bone study in a rat model.

Fungal dysbiosis predicts the diagnosis of pediatric Crohn's disease

AIM To investigate the accuracy of fungal dysbiosis inmucosa and stool for predicting the diagnosis of Crohn's disease(CD). METHODS Children were prospectively enrolled in two medical centers: one university hospital and one private gastroenterology clinic in the city of Riyadh, Kingdom of Saudi Arabia. The children with confirmed diagnosis of CD by standard guidelines were considered cases, and the others were considered non-inflammatory bowel disease controls. Mucosal and stool samples were sequenced utilizing Illumina MiSeq chemistry following the manufacturer's protocols, and abundance and diversity of fungal taxa in mucosa and stool were analyzed. Sparse logistic regression was used to predict the diagnosis of CD. The accuracy of the classifier was tested by computing the receiver operating characteristic curves with 5-fold stratified cross-validation under 100 permutations of the training data partition and the mean area under the curve(AUC) was calculated. RESULTS All the children were Saudi nationals. There were 15 children with CD and 20 controls. The mean age was 13.9(range: 6.7-17.8) years for CD children and 13.9(3.25-18.6) years for controls, and 10/15(67%) of the CD and 13/20(65%) of the control subjects were boys. CD locations at diagnosis were ileal(L1) in 4 and colonic(L3) in 11 children, while CD behavior was non-stricturing and non-penetrating(B1) in 12 and stricturing(B2) in 3 children. The mean AUC for the fungal dysbiosis classifier was significantly higher in stools(AUC = 0.85 ± 0.057) than in mucosa(AUC = 0.71 ± 0.067)(P < 0.001). Most fungal species were significantly more depleted in stools than mucosal samples, except for Saccharomyces cerevisiae and S. bayanus, which were significantly more abundant. Diversity was significantly more reduced in stools than in mucosa. CONCLUSION We found high AUC of fungal dysbiosis in fecal samples of children with CD, suggesting high accuracy in predicting diagnosis of CD.

Management and outcomes of congenital chylothorax in the neonatal intensive care unit:A case series

Importance:Congenital chylothorax is a rare condition with pulmonary and multiorgan system effects,for which there are no standardized treatment recommendations.Collective review of known cases offers some conclusions and suggestions for treatment.Objective:The aim of this study was to present a case series of 5 patients who were treated in the neonatal intensive care unit with chylothorax.Methods:We describe 5 infants who were diagnosed prenatally with hydrops fetalis and postnatally had clinically significant congenital chylothorax.Results:Treatment guidelines specific to congenital forms of chylothorax have not yet been developed,although there are consistent trends across our cases.Four of the 5 infants in this study have survived to date.Chylothorax was treated with chest tube placement and chylous fluid drainage,scrupulous attention to fluid balance,mechanical ventilation,and nutritional management and,in 3 cases,with octreotide infusions.Some of the infants also required treatment for immunodeficiency and altered coagulation pathways.None of the infants underwent surgical thoracic duct ligation.Interpretation:Aided by the advantage of prenatal diagnosis,many cases of congenital chylothorax can be successfully treated by a combination of nutritional and medical management as well as careful attention to fluid and electrolyte balance and avoidance of infection,thereby avoiding the need for surgical ligation of the thoracic duct.

The classification of ATP-binding cassette subfamily A member 3 mutations using the cystic fibrosis transmembrane conductance regulator classification system

Importance: The ATP-binding cassette subfamily A member 3 (ABCA3) protein plays a vital role in surfactant homeostasis. Mutations in the ABCA3 gene lead to the development of interstitial lung disease. In the most severe manifestation, mutations can lead to a fatal respiratory distress syndrome in neonates. ABCA3 belongs to the same ATP-binding cassette transporter superfamily as the cystic fibrosis transmembrane conductance regulator (CFTR), the gene that causes cystic fibrosis. Objective: To classify ABCA3 mutations in a manner similar to CFTR mutations in order to take advantage of recent advances in therapeutics. Methods: Sequence homology between the CFTR protein and the ABCA3 protein was established. The region of CFTR that is a target for the new potentiator class of drugs was of particular interest. We performed a literature search to obtain all published mutations that were thought to be disease causing. We classified these mutations using the established CFTR classification system. When possible, we drew on previous experimental classification of ABCA3 mutations. Results: Although the proteins share the same overall structure, only a 19％identity was established between CFTR and ABCA3. The CFTR therapeutic target region has a 22％ homology with the corresponding ABCA3 region. Totally 233 unique protein mutations were identified. All protein mutations were classified and mapped to a schematic diagram of the ABCA3 protein. Interpretation: This new classification system for ABCA3, based on CFTR classification, will likely aid further research of clinical outcomes and identification of mutation-tailored therapeutics, with the aim for improving clinical care for patients with ABCA3 mutations.