The versatility of the free osteocutaneous fibula flap in the reconstruction of extremities after sarcoma resection

BACKGROUND: An understanding of the biology of bone and soft-tissue sarcomas, knowledge of adjuvant therapies and refinement in techniques of reconstructive surgery have allowed limb-sparing and limb salvage surgery to become a reality in the management of malignant tumors of the extremities. Functional limb salvage following radical resection has become a possibility in many resectable tumors by the use of alloplastic prostheses, homograft or autogenous bone for skeletal reconstitution combined with vascularized soft tissue coverage. Although the free fibula flap has been well described for reconstructions of the mandible and oral cavity, it has not been widely presented as an ideal tool to preserve extremities and to circumvent amputation. PATIENTS AND METHODS: We describe the complex surgical reconstruction in four patients with primary sarcomas of the extremities. The sarcomas (Ewing's sarcoma, osteosarcoma and epitheloid sarcoma) were resected radically and the massive bone and soft tissue defect was replaced by vascularized free fibula transfer. RESULTS: We present our experience with versatility of this osteocutaneous flap to allow reconstruction and salvage of extremitity sarcomas. There were no operative or postoperative complication and all the four patients had good limb function. The flap was found to be versatile as it could be used for either upper limb or lower limb and for large defects. The results were better in upper limb than in lower limb. CONCLUSIONS: Free fibular graft was found to be effective for salvaging limb function where a massive bone defect resulted from wide tumor resection in the extremities

Proppant immobilization facilitated by carbon nanotube mediated microwave treatment of polymer-proppant structures

The application of multi-walled carbon nanotubes (MWCNTs) to facilitate the aggregation of ceramic particles (proppants) by embedding in the coating through localized microwave heating is reported. Thermogravimetric analysis (TGA), scanning electron microscopy (SEM) along with energy dispersive X-ray analysis (EDX) and atomic force microscopy (AFM) were used to characterize a series of covalently functionalized proppants with carboxylic acids (lysine and fumaric acid). The bi-functional acids allow for a controlled reaction with a coating (resin and polymer). The addition of carbon nanotubes results in the melting of the coating under exposure to microwave irradiation (20 s @ 100 W) joining the particles. The significant reduction in reaction time (compared to the thermal treatments of 2–24 hours) is due to the presence of the MWCNTs. The microwave heating of the MWCNTs can thus be used to create interaction and adhesion between functionalized particles subject to a specific stimulus

Missense mutation of Brain Derived Neurotrophic Factor (BDNF) alters neurocognitive performance in patients with mild traumatic brain injury: a longitudinal study

The predictability of neurocognitive outcomes in patients with traumatic brain injury is not straightforward. The extent and nature of recovery in patients with mild traumatic brain injury (mTBI) are usually heterogeneous and not substantially explained by the commonly known demographic and injury-related prognostic factors despite having sustained similar injuries or injury severity. Hence, this study evaluated the effects and association of the Brain Derived Neurotrophic Factor (BDNF) missense mutations in relation to neurocognitive performance among patients with mTBI. 48 patients with mTBI were prospectively recruited and MRI scans of the brain were performed within an average 10.1 (SD 4.2) hours post trauma with assessment of their neuropsychological performance post full Glasgow Coma Scale (GCS) recovery. Neurocognitive assessments were repeated again at 6 months follow-up. The paired t-test, Cohen’s d effect size and repeated measure ANOVA were performed to delineate statistically significant differences between the groups [wildtype G allele (Val homozygotes) vs. minor A allele (Met carriers)] and their neuropsychological performance across the time point (T1 = baseline/ admission vs. T2 = 6th month follow-up). Minor A allele carriers in this study generally performed more poorly on neuropsychological testing in comparison wildtype G allele group at both time points. Significant mean differences were observed among the wildtype group in the domains of memory (M = -11.44, SD = 10.0, p = .01, d = 1.22), executive function (M = -11.56, SD = 11.7, p = .02, d = 1.05) and overall performance (M = -6.89 SD = 5.3, p = .00, d = 1.39), while the minor A allele carriers showed significant mean differences in the domains of attention (M = -11.0, SD = 13.1, p = .00, d = .86) and overall cognitive performance (M = -5.25, SD = 8.1, p = .01, d = .66).The minor A allele carriers in comparison to the wildtype G allele group, showed considerably lower scores at admission and remained impaired in most domains across the timepoints, although delayed signs of recovery were noted to be significant in the domains attention and overall cognition. In conclusion, the current study has demonstrated the role of the BDNF rs6265 Val66Met polymorphism in influencing specific neurocognitive outcomes in patients with mTBI. Findings were more detrimentally profound among Met allele carriers

Recapitulating the tumor ecosystem along the metastatic cascade using 3D culture models

Advances in cancer research have shown that a tumor can be likened to a foreign species that disrupts delicately balanced ecological interactions, compromising the survival of normal tissue ecosystems. In efforts to mitigate tumor expansion and metastasis, experimental approaches from ecology are becoming more frequently and successfully applied by researchers from diverse disciplines to reverse engineer and re-engineer biological systems in order to normalize the tumor ecosystem. We present a review on the use of 3D biomimetic platforms to recapitulate biotic and abiotic components of the tumor ecosystem, in efforts to delineate the underlying mechanisms that drive evolution of tumor heterogeneity, tumor dissemination, and acquisition of drug resistance.ope

Frontal thermoclinic structure displaced by tidal/inertial motion during JASON 1978, Second Multiship Experiment

The three Federal German research vessels "Planet", "Meteor" and "Poseidon" participated in the Second Multiship Experiment during JASIN 1978 as stationary ships with CTD yo-yo profiling. The analysis is concerned mainly with the weakly stratified layer between the seasonal thermocline and the turbulent mixed layer. The thermoclinic structure of a front in that layer and its tidal/inertial displacement is described and is shown to be in accordance with current meter data from the H2 mooring. It is shown that the CTD yo-yos cannot be treated as pure time-series but that the movement of the ships relative to the seabed and relative to the front has to be taken into account. The method of isopycnic analysis was used to eliminate the effect of internal waves. Temporal coordinates can be converted to spatial coordinates allowing for the tidal/inertial movements. Thus high resolution sections through the front can be given. The thermohaline structure is described on density levels in the seasonal thermocline and in the weakly stratified layer above it