Vertically grown TiO 2 -nanotubes (TiO 2 -NT) on a Ti metal substrate synthesized by electrochemical anodization followed by calcination have been studied using X-ray absorption near-edge structures (XANES) and X-ray excited optical luminescence (XEOL). It is found that the TiO 2 -NT system undergoes a series of phase transformations from amorphous (as-prepared) to anatase (400 °C) to rutile (>600 °C); the phase and morphology transformation is accompanied by unusual light-emitting properties, which are strongly dependent upon the crystal phase and morphology controlled by calcination temperatures, i.e. the as-prepared TiO 2 -NT exhibits no luminescence, whereas the anatase phase exhibits green luminescence, and an intense near-IR emission dominates in the rutile phase. The implications of these observations are discussed.

An intact extracellular matrix (ECM) with a mesh-like architecture has been identified in the peri-muscular sub-serosal connective tissue (PSCT) of cholecyst (gallbladder). The PSCT layer of cholecyst wall is isolated by mechanical delamination of other layers and decellularized with a treatment with peracetic acid and ethanol solution (PES) in water to obtain the final matrix, which is referred to as cholecyst-derived ECM (CEM). CEM is cross-linked with different concentrations of glutaraldehyde (GA) to demonstrate that the susceptibility of CEM to degradation can be controlled. Quantitative and qualitative macromolecular composition assessments revealed that collagen is the primary structural component of CEM. Elastin is also present. In addition, the ultra-structural studies on CEM reveal the presence of a three-dimensional fibrous mesh-like network structure with similar nanoscale architecture on both mucosal and serosal surfaces. In vitro cell culture studies show that CEM provides a supporting structure for the attachment and proliferation of murine fibroblasts (3T3) and human umbilical vein endothelial cells (HUVEC). CEM is also shown to support the attachment and differentiation of rat adrenal pheochromocytoma cells (PC12).

Background Interposition vein grafts (IVG) and vascular bridge flaps (VBF) have been exploited as vascular conduit in challenging head and neck reconstructions. Methods A retrospective review was conducted on 6025 flaps. The effect of patients' characteristics and length of IVG on flap compromise and loss were analyzed. Comparison between IVG and VBF was performed. Results The flap compromise and loss rates for the overall group were 8.2% and 3.2%, respectively. An IVG was used in 309 free flaps. The average length of the vein grafts was 6.9 ± 4.2 cm. An unplanned return to the operation room occurred in 32 cases (10.4%) and failure of the flap in 12 patients (3.9%). Binary logistic regression found a significant association between flap compromise and loss rates and length of IVG, hypertension, prior radiation, and neck dissection. In the multiple regression model, length of IVG and prior radiation significantly influenced the outcomes. Thirty‐nine patients underwent reconstruction with a long IVG (>10 cm). Twenty‐six patients underwent surgical reconstruction with radial forearm flap as a VBF. The rate of flap compromise was higher in the group with a long IVG (P = .01). Conclusions In head and neck free flap reconstruction, the length of IVGs and history of radiotherapy are associated with flap compromise and loss. In case of long distance between the pedicle and the recipient site, the use of a VBF bridge should be considered as a safe alternative.

Flexor tendon repair: a comparative study between a knotless barbed suture repair and a traditional four-strand monofilament suture repair. We compared the tensile strength of a novel knotless barbed suture method with a 2 traditional four-strand Adelaide technique for flexor tendon repairs. Forty fresh porcine 3 flexor tendons were transected and randomly assigned to one of the repair groups before 4 repair. Biomechanical testing demonstrated that the tensile strengths between both tendon 5 groups were very similar. However, less force was required to create a 2 mm gap in the 6 four-strand repair method compared with the knotless barbed technique. There was a 7 significant reduction in the cross-sectional area in the barbed suture group after repair 8 compared with the Adelaide group. This would create better gliding within the pulley 9 system in vivo and could decrease gapping and tendon rupture. 10 11 Strickland (1995; 2000) reported that the ideal flexor tendon repair includes safe, easily 12 placed sutures to permit the stress of early post-operative motion, close approximation 13 between the tendon sections with little gapping, congruity of the tendon ends, and a 14 minimally compromised tendon blood supply. 15 INTRODUCTIONFactors that affect the strength of a flexor tendon have been well researched and include 16 the type and diameter of suture material used (Wada et al., 2001) the number of strands 17 crossing the repair site (Barrie et al., 2000) the length of core suture purchase (Cao et al., 18 2006; Tang et al., 2005), the number of throws on the knot (Strick et al., 2004), the tension 19 of the core suture (Wu and Tang, 2012) and the method of epitendinous repair (Moriya et 20 al., 2010). Suture rupture as a cause of repair failure has almost been eliminated because of 21 advances in suture materials and the refinement of multi-strand repair techniques (Parikh et 22 al., 2009). Nowadays, the tensile strength of flexor tendon repairs is limited by inadequate 23 suture-tendon interaction at the site of locking loops as well as failure of the suture knot 24 (Tang et al., 2005; Trail et al., 1989; Xie and Tang, 2005) MATERIALS AND METHODS 20Forty fresh porcine flexor digitorum profundus tendons were obtained for our study. These 21 were chosen as they have been used in many previous studies on the tensile strengths of 22 tendon repairs. They have similar biomechanical properties to the flexor tendon of the 23 middle finger in humans (Cao et al., 2006; Hausmann et al., 2009; Mao et al., 2011; Rigó et 24 al., 2012;Smith et al., 2005; Tang et al., 2005). We examined all the tendons for any 25 4 abnormalities and imperfections including synovitis, degeneration and trauma. Those that 1 had any defects were rejected. 2 3 Cross-sectional area measurements 4To ensure all tendons were of a similar size, the height and width of each tendon was 5 measured using a caliper (Digi-Max™ Slide Caliper, Bel-Art, N.J., USA). Measurements were 6 taken at the repair site and also 1 cm proximal and 1 cm ...

A method to functionalize cholecyst-derived extracellular matrix (CEM) with free amine groups was established in an attempt to improve its potential for tethering of bioactive molecules. CEM was incorporated with Generation-1 polyamidoamine (G1 PAMAM) dendrimer by using N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide and N-hydroxysuccinimide cross-linking system. The nature of incorporation of PAMAM dendrimer was evaluated using shrink temperature measurements, Fourier transform infrared (FTIR) assessment, ninhydrin assay, and swellability. The effects of PAMAM incorporation on mechanical and degradation properties of CEM were evaluated using a uniaxial mechanical test and collagenase degradation assay, respectively. Ninhydrin assay and FTIR assessment confirmed the presence of increasing free amine groups with increasing quantity of PAMAM in dendrimer-incorporated CEM (DENCEM) scaffolds. The amount of dendrimer used was found to be critical in controlling scaffold degradation, shrink temperature, and free amine content. Cell culture studies showed that fibroblasts seeded on DENCEM maintained their metabolic activity and ability to proliferate in vitro. In addition, fluorescence cell staining and scanning electron microscopy analysis of cell-seeded DENCEM showed preservation of normal fibroblast morphology and phenotype.

No abstract

Background and ObjectivesIn patients with lymphedema, the disruption of the lymphatic network increases skin turgor and fibrosis of subcutaneous tissue, delays wound healing, causing recurrent ulcerations and infections. In these cases, management of ulcers can be challenging.MethodsBetween January 2016 and June 2018, patients presenting with lymphedema were enrolled at our Institution. We selected patients with severe lymphedema and ulcers of lower limbs and we performed a surgical approach, involving free gastroepiploic lymph nodes and omentum flap, harvested through laparoscopy.ResultsWe enrolled 135 patients presenting for lymphedema. Among them, 10 eligible cases underwent excision of the ulcer and reconstruction with omentum flap. Mean age was 57.8 years and average follow‐up 24.1 months. Circumferences and skin tonicity significantly decreased from the preoperative period. Lymphoscintigraphy showed improvement of the lymphatic drainage and restoration of lymphatic network. No episodes of infection were recorded in the postoperative period.ConclusionsOur combined procedure merges free flap techniques and lymphedema surgery: omentum covers the defect while providing a new source of lymph nodes, improving the lymphatic networks of the affected limb. This technique can highly increase the quality of life of the patient in a single‐stage operation with fast recovery and low donor site morbidity.

No abstract