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Highly porous emulsion templated polymers (PolyHIPEs) provide a number of potential advantages in the fabrication of scaffolds for tissue engineering and regenerative medicine. Porosity enables cell ingrowth and nutrient diffusion within, as well as waste removal from, the scaffold. The properties offered by emulsion templating alone include the provision of high interconnected porosity, and, in combination with additive manufacturing, the opportunity to introduce controlled multiscale porosity to complex or custom structures. However, the majority of monomer systems reported for PolyHIPE preparation are unsuitable for clinical applications as they are nondegradable. Thiol-ene chemistry is a promising route to produce biodegradable photocurable PolyHIPEs for the fabrication of scaffolds using conventional or additive manufacturing methods; however, relatively little research has been reported on this approach. This study reports the groundwork to fabricate thiol- and polycaprolactone (PCL)-based PolyHIPE materials via a photoinitiated thiolene click reaction. Two different formulations, either three-arm PCL methacrylate (3PCLMA) or four-arm PCL methacrylate (4PCLMA) moieties, were used in the PolyHIPE formulation. Biocompatibility of the PolyHIPEs was investigated using human dermal fibroblasts (HDFs) and human osteosarcoma cell line (MG-63) by DNA quantification assay, and developed PolyHIPEs were shown to be capable of supporting cell attachment and viability.

Wound healing involves a complex series of events where cell–cell and cell-extracellular matrix (ECM) interactions play a key role. Wounding can be simple, such as the loss of the epithelial integrity, or deeper and more complex, reaching to subcutaneous tissues, including blood vessels, muscles and nerves. Rapid neovascularisation of the wounded area is crucial for wound healing as it has a key role in supplying oxygen and nutrients during the highly demanding proliferative phase and transmigration of inflammatory cells to the wound area. One approach to circumvent delayed neovascularisation is the exogenous use of pro-angiogenic factors, which is expensive, highly dose-dependent, and the delivery of them requires a very well-controlled system to avoid leaky, highly permeable and haemorrhagic blood vessel formation. In this study, we decorated polycaprolactone (PCL)-based polymerised high internal phase emulsion (PolyHIPE) scaffolds with fibroblast-derived ECM to assess fibroblast, endothelial cell and keratinocyte activity in vitro and angiogenesis in ex ovo chick chorioallantoic membrane (CAM) assays. Our results showed that the inclusion of ECM in the scaffolds increased the metabolic activity of three types of cells that play a key role in wound healing and stimulated angiogenesis in ex ovo CAM assays over 7 days. Herein, we demonstrated that fibroblast-ECM functionalised PCL PolyHIPE scaffolds appear to have great potential to be used as an active wound dressing to promote angiogenesis and wound healing.

Tissue engineering (TE)-based bone grafts are favorable alternatives to autografts and allografts. Both biochemical properties and the architectural features of TE scaffolds are crucial in their design process. Synthetic polymers are attractive biomaterials to be used in the manufacturing of TE scaffolds, due to various advantages, such as being relatively inexpensive, enabling precise reproducibility, possessing tunable mechanical/chemical properties, and ease of processing. However, such scaffolds need modifications to improve their limited interaction with biological tissues. Structurally, multiscale porosity is advantageous over single-scale porosity; therefore, in this study, we have considered two key points in the design of a bone repair material; (i) manufacture of multiscale porous scaffolds made of photocurable polycaprolactone (PCL) by a combination of emulsion templating and three-dimensional (3D) printing and (ii) decoration of these scaffolds with the in vitro generated bone-like extracellular matrix (ECM) to create biohybrid scaffolds that have improved biological performance compared to PCL-only scaffolds. Multiscale porous scaffolds were fabricated, bone cells were cultured on them, and then they were decellularized. The biological performance of these constructs was tested in vitro and in vivo. Mesenchymal progenitors were seeded on PCL-only and biohybrid scaffolds. Cells not only showed improved attachment on biohybrid scaffolds but also exhibited a significantly higher rate of cell growth and osteogenic activity. The chick chorioallantoic membrane (CAM) assay was used to explore the angiogenic potential of the biohybrid scaffolds. The CAM assay indicated that the presence of the in vitro generated ECM on polymeric scaffolds resulted in higher angiogenic potential and a high degree of tissue infiltration. This study demonstrated that multiscale porous biohybrid scaffolds present a promising approach to improve bioactivity, encourage precursors to differentiate into mature bones, and to induce angiogenesis.

Vaginal meshes used in the treatment of stress urinary incontinence (SUI) and pelvic organ prolapse (POP) have produced highly variable outcomes, causing life-changing complications in some patients while providing others with effective, minimally invasive treatments. The risk:benefit ratio when using vaginal meshes is a complex issue in which a combination of several factors, including the inherent incompatibility of the mesh material with some applications in pelvic reconstructive surgeries and the lack of appropriate regulatory approval processes at the time of the premarket clearance of these products, have contributed to the occurrence of complications caused by vaginal mesh. Surgical mesh used in hernia repair has evolved over many years, from metal implants to knitted polymer meshes that were adopted for use in the pelvic floor for treatment of POP and SUI. The evolution of the material and textile properties of the surgical mesh was guided by clinical feedback from hernia repair procedures, which were also being modified to obtain the best outcomes with use of the mesh. Current evidence shows how surgical mesh fails biomechanically when used in the pelvic floor and materials with improved performance can be developed using modern material processing and tissue engineering techniques.

It’s a pleasure for us to take your offer to prepare a brief report on neonatal tetanus (NT). Regarding our study entitled "Neonatal tetanus in Turkey; what has changed in the last decade?" had been published in 2008 [1]; we want to emphasize the level reached in the field of neonatal tetanus under the light of the knowledge gathered in recent ten years, and we want to share with your journal.

Gulkesen, Kemal Hakan/0000-0002-2477-2481 WOS: 000256716300267 …

Aim: To evaluate the efficacy of two regimens of combined interferon-alpha 2a (IFN-alpha 2a) and lamivudine (3TC) therapy in childhood chronic hepatitis B.

ECE, AYDIN/0000-0001-9130-2431; Ece, Aydin/0000-0001-6764-8336; dikici, bunyamin/0000-0001-7572-6525 WOS: 000182327600008 PubMed: 12690275 Aim. Hepatitis B virus (HBV) infection is a major global health concern and is the most common cause of chronic liver disease worldwide. Our aim was to investigate the efficacy of specific HBV vaccination as active immunotherapy in treating chronic hepatitis B (CHB) infection during the immunotolerant phase of children with normal aminotransferase values and high viral load. Materials and methods. Seventy-four patients never vaccinated before were randomly and prospectively recruited into two groups. Group 1 included 43 patients vaccinated with three standard injections of the GenHevac B vaccine at 30-day intervals. Group 2 contained 31 patients who did not receive any medication or vaccination (control group). Postvaccination serologic and virologic evaluation was performed 6 months after the first injection and at the end of the 12th month. Response to therapy was defined as loss of HBV DNA in serum and hepatitis B e antigen (HBeAg) seroconversion (loss of HBeAg), development of hepatitis B e antibody (anti-HBe). Results. The mean baseline alanine aminotransferase (ALT) value in Group 1 was 33.0 +/- 9.6 IU/I, 34.6 +/- 13.9 IU/I at 6 months after first injection and 34.3 +/- 17.1 IU/I at end of 12 months (P > 0.05). In Group I the HBV DNA load at the start of immunization was 3571 +/- 1292 pg/ml; this value was 3220 +/- 1217 pg/ml at the 6th month and 2931 +/- 1292 pg/ml at the 12th month (P > 0.05). In Group 2 the mean ALT values at the beginning of therapy and at the 6th and 12th months were 32.6 +/- 7.8, 32.3 +/- 8.0 and 30.3 +/- 7.3 IU/I, respectively (P > 0.05), and the mean viral load HBV DNA values were 3909 1378, 3546 869 and 3106 +/- 718 pg/ml, respectively (P > 0.05). There was no statistically significant difference between Group 1 and Group 2 at the end of the 6th and 12th months in the mean ALT values and mean viral load of HBV DNA (P > 0.05). Except for one patient in each group, hepatitis B surface antigen and HBeAg clearance or hepatitis B surface antibody and anti-HBe seroconversion were not observed during follow-up (P > 0.05). Conclusion. In this multicentered study comparison of vaccinated and unvaccinated groups of immunotolerant children with CHB infection showed no difference in the clearance of HBV DNA or seroconversion from HBeAg to anti-HBe. Different immunization protocols should be considered for future investigations in the inununo-tolerant phase of children with CHB infection.