A novel unsaturated polyphosphoester (UPPE) was devised in our previous research, which is a kind of promising scaffold for improving bone regeneration. However, the polymerization process of UPPE scaffolds was unfavorable, which may adversely affect the bioactivity of osteoinductive molecules added if necessary, such as recombinant human bone morphogenetic protein-2 (rhBMP2). The purpose of this study was to build a kind of optimal scaffold named UPPE-PLGA-rhBMP2 (UPB) and to investigate the bioactivity of rhBMP2 in this scaffold. Furthermore, the cytotoxicity and biocompatibility of UPB scaffold was assessed in vitro. A W1/O/W2 method was used to fabricate PLGA-rhBMP2 microspheres, and then the microspheres were added to UPPE for synthesizing UPB scaffold. The morphological characters of PLGA-rhBMP2 microspheres and UPB scaffolds were observed under the scanning electron microscopy and laser scanning confocal microscopy. The cumulative release of UPB scaffolds was detected by using ELISA. The cytotoxicity and biocompatibility of UPB scaffolds were evaluated through examining the adsorption and apoptosis of bone marrow stromal cells (bMSCs) seeded on the surface of UPB scaffolds. The bioactivity of rhBMP2 in UPB scaffolds was assessed through measuring the alkaline phosphates (ALP) activity in bMSCs seeded. The results showed that UPB scaffolds sequentially exhibited burst and sustained release of rhBMP2. The cytotoxicity was greatly reduced when the scaffolds were immersed in buffer solution for 2 h. bMSCs attached and grew on the surface of soaked UPB scaffolds, exerting well biocompatibility. The ALP activity of bMSCs seeded was significantly enhanced, indicating that the bioactivity of rhBMP2 remained and still took effect after the unfavorable polymerization process of scaffolds. It was concluded that UPB scaffolds have low cytotoxicity, good biocompatibility and preserve bioactivity of rhBMP2. UPB scaffolds are promising in improving bone regeneration.

OBJECTIVETo investigate the clinical and laboratory features of very long chain acyl-CoA dehydrogenase deficiency ( VLCADD ) and the correlations between its genotype and phenotype.

METHODEleven patients diagnosed as VLCADD of Shanghai Jiaotong University School of Medicine seen from September 2006 to May 2014 were included. There were 9 boys and 2 girls, whose age was 2 d-17 years. Analysis was performed on clinical features, routine laboratory examination, and tandem mass spectrometry (MS-MS) , gas chromatography mass spectrometry (GC-MS) and genetic analysis were conducted.

RESULTAll cases had elevated levels of blood tetradecanoylcarnitine (C14:1) recognized as the characteristic biomarker for VLCADD. The eleven patients were classified into three groups: six cases in neonatal onset group, three in infancy onset group form patients and two in late onset group. Neonatal onset patients were characterized by hypoactivity, hypoglycemia shortly after birth. Infancy onset patients presented hepatomegaly and hypoglycemia in infancy. The two adolescent patients showed initial manifestations of exercise intolerance or rhabdomyolysis. Six of the eleven patients died at the age of 2-8 months, including four neonatal onset and two infant onset patients, with one or two null mutations. The other two neonatal onset patients were diagnosed since early birth through neonatal screening and their clinical manifestation are almost normal after treatments. Among 11 patients, seventeen different mutations in the ACADVL gene were identified, with a total mutation detection rate of 95.45% (21/22 alleles), including eleven reported mutations ( p. S22X, p. G43D, p. R511Q, p. W427X, p. A213T, p. C215R, p. G222R, p. R450H, p. R456H, c. 296-297delCA, c. 1605 + 1G > T) and six novel mutations (p. S72F, p. Q100X, p. M437T, p. D466Y, c. 1315delG insAC, IVS7 + 4 A > G). The p. R450H was the most frequent mutation identified in three alleles (13.63%, 3/22 alleles), followed by p. S22X and p. D466Y mutations which were detected in two alleles (9.09%, 2/22 alleles).

CONCLUSIONThe ACADVL gene mutations were heterozygous in our patients. The mortality of neonatal onset form and infant onset form is much higher than the late onset form patients, suggesting a certain correlation between the genotype and phenotype was found. The earlier diagnosis and treatment of VLCADD are of vital importance for the improvement of the prognosis of the patients.

Acyl-CoA Dehydrogenase, Long-Chain ; deficiency ; genetics ; Adolescent ; Age of Onset ; Alleles ; Asian Continental Ancestry Group ; Child ; Child, Preschool ; China ; Female ; Genetic Testing ; Genotype ; Heterozygote ; Humans ; Infant ; Infant, Newborn ; Lipid Metabolism, Inborn Errors ; complications ; genetics ; Male ; Mitochondrial Diseases ; complications ; genetics ; Muscular Diseases ; complications ; genetics ; Mutation ; Neonatal Screening ; Phenotype ; Prognosis ; Rhabdomyolysis ; etiology ; Spectrum Analysis ; Tandem Mass Spectrometry

Summary: The aim of this study was to investigate the in vitro cytotoxieity of polyphosphoester polymer used as a novel injectable alveolar bone substitutes for controlled delivery of tetracycline. Cell culture medium was exposed to the polymer (0.01-10 mg/mL) for 24h. The L-929 mouse fibroblasts were then exposed to the treated cell culture medium for 24h. Finally, cell viability and growth were assessed by using MTT assay and Alamar Blue assay. No significant cytotoxicity of the polyphosphoester against L-929 mouse fibroblasts was observed at a concentration up to 10 mg/mL (P0.05). The two evaluation methods showed no significant differences (P0.05). This study suggests that polyphosphoester does not demonstrate any significant toxic effects to cells in vitro and has the potential to be used both as a medical device and as scaffolds in tissue engineering applications.

A novel unsaturated polyphosphoester (UPPE) was devised in our previous research, which is a kind of promising scaffold for improving bone regeneration. However, the polymerization process of UPPE scaffolds was unfavorable, which may adversely affect the bioactivity of osteoinductive molecules added if necessary, such as recombinant human bone morphogenetic protein-2 (rhBMP2). The purpose of this study was to build a kind of optimal scaffold named UPPE-PLGA-rhBMP2 (UPB) and to investigate the bioactivity of rhBMP2 in this scaffold. Furthermore, the cytotoxicity and biocompatibility of UPB scaffold was assessed in vitro. A W1/O/W2 method was used to fabricate PLGA-rhBMP2 microspheres, and then the microspheres were added to UPPE for synthesizing UPB scaffold. The morphological characters of PLGA-rhBMP2 microspheres and UPB scaffolds were observed under the scanning electron microscopy and laser scanning confocal microscopy. The cumulative release of UPB scaffolds was detected by using ELISA. The cytotoxicity and biocompatibility of UPB scaffolds were evaluated through examining the adsorption and apoptosis of bone marrow stromal cells (bMSCs) seeded on the surface of UPB scaffolds. The bioactivity of rhBMP2 in UPB scaffolds was assessed through measuring the alkaline phosphates (ALP) activity in bMSCs seeded. The results showed that UPB scaffolds sequentially exhibited burst and sustained release of rhBMP2. The cytotoxicity was greatly reduced when the scaffolds were immersed in buffer solution for 2 h. bMSCs attached and grew on the surface of soaked UPB scaffolds, exerting well biocompatibility. The ALP activity of bMSCs seeded was significantly enhanced, indicating that the bioactivity of rhBMP2 remained and still took effect after the unfavorable polymerization process of scaffolds. It was concluded that UPB scaffolds have low cytotoxicity, good biocompatibility and preserve bioactivity of rhBMP2. UPB scaffolds are promising in improving bone regeneration.
Bone Morphogenetic Protein 2 ; chemistry ; pharmacology ; Bone Regeneration ; drug effects ; Humans ; Lactic Acid ; chemistry ; pharmacology ; Phosphatidylinositol Phosphates ; chemistry ; pharmacology ; Polyglycolic Acid ; chemistry ; pharmacology ; Tissue Scaffolds