Novel electrospun polycaprolactone/graphene oxide/Fe3O4 nanocomposites for biomedical applications.

In this study, one of the most promising methods of tailoring a composite scaffold material in nano sized diameters, electrospinning method were used to produce Polycaprolactone (PCL)/Graphene Oxide (GO)/Iron(II, III) Oxide (Fe3O4) nanocomposite fibers as biocompatible scaffolds for biomedical applications. Products were analyzed by scanning electron microscopy (SEM) for morphological analysis of the electrospun nanocomposites and Fourier Transform Infrared Spectroscopy (FTIR) was used to determine functional groups of the PCL, GO, and Fe3O4 materials in the electrospun nanocomposites. For physical properties, viscosity, density, permittivity, dielectric loss and liquid and solid state alternating current conductivity, measurements were done for each nanocomposite fibers. Effects of concentration percentage of GO on permittivity, dielectric loss and AC conductivity have been analyzed by using measured and calculated data. Trend lines have been drawn for permittivity, dielectric loss and conductivity via concentration percentage of GO. The relation between ac conductivity and frequency have been studied for each concentration percentage of GO and interpretations have been done by using the obtained results.

Osteogenesis of human adipose-derived stem cells on poly(dopamine)-coated electrospun poly(lactic acid) fiber mats.

Electrospinning is a versatile technique to generate large quantities of micro- or nano-fibers from a wide variety of shapes and sizes of polymer. The aim of this study is to develop functionalized electrospun nano-fibers and use a mussel-inspired surface coating to regulate adhesion, proliferation and differentiation of human adipose-derived stem cells (hADSCs). We prepared poly(lactic acid) (PLA) fibers coated with polydopamine (PDA). The morphology, chemical composition, and surface properties of PDA/PLA were characterized by SEM and XPS. PDA/PLA modulated hADSCs' responses in several ways. Firstly, adhesion and proliferation of hADSCs cultured on PDA/PLA were significantly enhanced relative to those on PLA. Increased focal adhesion kinase (FAK) and collagen I levels and enhanced cell attachment and cell cycle progression were observed upon an increase in PDA content. In addition, the ALP activity and osteocalcin of hADSCs cultured on PDA/PLA were significantly higher than seen in those cultured on a pure PLA mat. Moreover, hADSCs cultured on PDA/PLA showed up-regulation of the ang-1 and vWF proteins associated with angiogenesis differentiation. Our results demonstrate that the bio-inspired coating synthetic degradable PLA polymer can be used as a simple technique to render the surfaces of synthetic biodegradable fibers, thus enabling them to direct the specific responses of hADSCs.

Clinical outcome and radiographic change of ipsilateral scapular neck and clavicular shaft fracture: comparison of operation and conservative treatment.

OBJECTIVE: The purpose of this study is to compare glenopolar angle (GPA) and the functional outcomes of fixation of both the clavicle and the scapular neck, fixation of the clavicle alone, and conservative treatment for floating-shoulder injuries. METHODS: A prospective stratified randomized study was performed in 39 adult patients who suffered floating-shoulder injuries and underwent fixation of both the clavicle and the scapular neck (group A), or fixation of the clavicle alone (group B), or conservative treatment (group C) between January 2005 and September 2011. The GPA, Disabilities of the Arm, Shoulder and Hand (DASH) score, and Constant-Murley Shoulder Outcome (Constant) score were compared between the three groups. RESULTS: All 39 patients were followed up for more than 2 years. GPA after bony consolidation was significantly better in group A than in groups B and C (p = 0.015). Functional outcomes measured by DASH and Constant scores were significantly better in group A at final follow-up (p = 0.008 and 0.002, respectively). Both DASH and Constant scores were highly correlated with GPA after consolidation (p < 0.001, respectively). The receiver operating characteristic (ROC) analysis showed that of the two randomly selected DASH scores, the smaller DASH score would have a larger GPA than the larger DASH score. Similarly, the larger Constant score would have a larger GPA than the smaller Constant score. CONCLUSIONS: Fixation of both the clavicle and the scapular neck may correct GPA and improve functional outcomes for the treatment of floating-shoulder injuries. GPA after fracture consolidation is a useful prognostic indicator of a satisfactory clinical outcome as defined by either DASH score or Constant score.

TiO2 nanowire FET device: encapsulation of biomolecules by electro polymerized pyrrole propylic acid.

Silane-based methods have become the standards for the conjugation of biomolecules, especially for the preparation of one-dimensional nanomaterial biosensors. However, the specific binding of those target molecules might raise problems with regard to the sensing and non-sensing regions, which may contaminate the sensing devices and decrease their sensitivity. This paper attempts to explore the encapsulation of biomolecules on a one-dimensional nanomaterial field effect transistor (FET) biosensor using polypyrrole propylic acid (PPa). Specifically, the encapsulation of biomolecules via the electropolymerization of pyrrole propylic acid (Pa), a self-made low-conductivity polymer, on TiO(2)-nanowire (NW)-based FETs is presented. The energy dispersive spectrum (EDS) was obtained and electrical analysis was conducted to investigate PPa entrapping anti-rabbit IgG (PPa/1°Ab) on a composite film. The specificity, selectivity and sensitivity of the sensor were analyzed in order to determine the immunoreaction of PPa/1°Ab immobilized NW biosensors. Our results show that PPa/1°Ab achieved high specificity immobilization on NWs under the EDS analysis. Furthermore, the TiO(2)-NW FET immunosensor developed in this work successfully achieved specificity, selectivity and sensitivity detection for the target protein rabbit IgG at the nano-gram level. The combination of PPa material and the electropolymerization method may provide an alternative method to immobilize biomolecules on a specific surface, such as NWs.

A surgical model of fulminant hepatic failure in rabbits.

AIM: Animal models of fulminant hepatic failure (FHF) have been developed for characterization of disease progression and to evaluate the effectiveness of liver-assist devices, some by treatment with hepatotoxic drugs, viral hepatitis or surgical procedures. We have developed a model in the rabbit by combining resection of the three anterior lobes with ligation of the pedicle of the right lateral lobes, resulting in liver necrosis; the remnant quadrate lobes are left intact. MATERIALS AND METHODS: Adult male New Zealand white rabbits (n=16) were used. Six animals were killed to measure the weight of the separate liver lobes. The others (n=10) underwent left neck central line placement to monitor continuous blood pressure and collect blood for laboratory analysis, and a burr hole on the right parietal bone to monitor the intracranial pressure (ICP). Blood laboratory analysis, clinical hepatic encephalopathy and ICP levels were measured in FHF animals (n=6). Animals (n=4) undergoing a sham operation served as controls. RESULTS: All FHF animals died between 12 and 26 h after liver surgery from FHF characterized by a progressive increase in liver enzymes, ammonia, total bilirubin, coagulopathy, hepatic encephalopathy and intracranial hypertension. Histological features of the ischaemic lobes showed coagulative necrosis of hepatocytes with absence of nuclei and collapse of cell plates. Brain histology revealed hypoxic cell damage. CONCLUSION: We have developed a simple, reproducible model of FHF in rabbits that has a number of features comparable with clinical FHF patients and is well suited for testing experimental bioartificial liver systems and investigating the pathogenesis of FHF.