[Effects of a Customized Health Promotion Program on Depression, Cognitive Functioning, and Physical Health of Elderly Women Living Alone in Community: A Cluster Randomized Controlled Trial].

PURPOSE: This study aimed to evaluate the effectiveness of a customized health promotion program (CHPP) on depression, cognitive functioning, and physical health of elderly women living alone in the community. METHODS: A randomized comparison of pre-and post-test design was used with 62 participants assigned to either an intervention (n=32 in seven clusters) or a control group (n=30 in seven clusters) in 14 areas of a town. The final sample included 30 intervention participants who completed the CHPP for 10 weeks, and 26 control participants. The intervention group participated in the CHPP weekly; they were provided with instructions about coping with their chronic illnesses, lifestyle modification, risk management, providing emotional support to each other, and floor-seated exercise, which they were encouraged to do three times a week in their homes. RESULTS: Significant group differences were found in depression (U=48.50, p<.001), cognitive functioning (U=2.50, p<.001), left arm flexibility (U=251.50, p=.023), right arm flexibility (U=225.00, p=.007), static balance (U=237.00, p=.012), and gait ability (U=190.50, p=.004). However, there were no significant differences in bothgrip strength and muscle mass between the two groups. CONCLUSION: The findings indicate that CHPP was overall effective at improving depression, cognitive functioning, and physical functioning of elderly women living alone, and could therefore be considered a positive program for community-dwelling elderly women living alone.

NF-κB signaling is key in the wound healing processes of silk fibroin.

Silk fibroin (SF) is a well-studied biomaterial for tissue engineering applications including wound healing. However, the signaling mechanisms underlying the impact of SF on this phenomenon have not been determined. In this study, through microarray analysis, regulatory genes of NF-ĸB signaling were activated in SF-treated NIH3T3 cells along with other genes. Immunoblot analysis confirmed the activation of the NF-ĸB signaling pathway as SF induced protein expression levels of IKKα, IKKß, p65, and the degradation of IκBα. The treatment of NIH3T3 cells with SF also increased the expression of cyclin D1, vimentin, fibronectin, and vascular endothelial growth factor (VEGF). The expression of these factors by SF treatment was abrogated when NF-ĸB was inhibited by a pharmacological inhibitor Bay 11-7082. Knockdown of NF-ĸB using siRNA of IKKα and IKKß also inhibited the SF-induced wound healing response of the NIH3T3 cells in a wound scratch assay. Collectively, these results indicated that SF-induced wound healing through the canonical NF-κB signaling pathway via regulation of the expression of cyclin D1, vimentin, fibronectin, and VEGF by NIH3T3 cells. Using an in vivo study with a partial-thickness excision wound in rats we demonstrated that SF-induced wound healing via NF-κB regulated proteins including cyclin D1, fibronectin, and VEGF. The in vitro and in vivo data suggested that SF induced wound healing via modulation of NF-ĸB signaling regulated proteins. STATEMENT OF SIGNIFICANCE: Silk fibroin has been effectively used as a dressing for wound treatment for more than a century. However, mechanistic insight into the basis for wound healing via silk fibroin has not been elucidated. Here we report a key mechanism involved in silk fibroin induced wound healing both in vitro and in vivo. Using genetic- and protein-level analyses, NF-κB signaling was found to regulate silk fibroin-induced wound healing by modulating target proteins. Thus, the NF-κB signaling pathway may be utilized as a therapeutic target during the formulation of silk fibroin-based biomaterials for wound healing and tissue engineering.

In vitro and in vivo evaluation of the duck's feet collagen sponge for hemostatic applications.

Recently different hemostatic agents have been developed, but most of them are ineffective in severe bleeding and expensive or cause safety concerns. In this study, we fabricated duck's feet collagen-based porous sponges and investigated its use as a hemostatic agent. We determined the sponge's physical and biological characteristics and compared with Avitene via scanning electron microscope analysis, water-uptake abilities and porosity test, and cytotoxicity assay. The duck's feet collagen/silk sponge showed a larger interconnected porous structure compared to others sponges. The duck's feet collagen/silk sponge also exhibited significantly higher porosity than Avitene. Hemostatic properties of the sponges were evaluated by whole blood clotting and rat femoral artery hemorrhage experiment. The addition of silk to duck's feet collagen showed better blood clotting ability than Avitene in vitro. However, rat femoral artery hemorrhage test showed a similar hemostatic property between the duck's feet collagen-based sponges and Avitene. We suggest that duck's feet collagen-based sponge can be effectively used for hemostatic applications.

Application of a Collagen Patch Derived from Duck Feet in Acute Tympanic Membrane Perforation.

We investigated the utility of the duck-feet collagen extraction patching procedure in the traumatic tympanic membrane (TM) perforation via a comparison with spontaneous healing or paper patch. Fifty-six ears of adult male Sprague-Dawley rats, each weighing in the range of 250 to 300 g, were used for the animal studies. Sixteen rats had one-side ear in the control group and the opposite-side ear in the treated groups. The remaining twelve rats had a one-side ear with the duck-feet collagen patch and the opposite-side ear with a paper patch. The proliferating cell nuclear antigen (PCNA) expression cells were calculated among the 200 basal cells, and the expression percentage was identified as the labeling index. The healing of the perforation in the duck-feet collagen patch group was confirmed to be more rapid compared to the healing of the other groups. PCNA staining was observed in the migrating portion of PCNA enhanced cell to collagen scaffold in Post operative day (POD) 7 of collagen patch group. Thus, the adhesive effect of the duck-feet collagen patch to perforated margin was better than that of the paper patch. After completing the healing process, the collagen patch shrank and detached from the tympanic membrane (POD 14). In this study, we confirmed that the use of a duck-feet collagen patch had the advantage of early healing, inducing natural TM contour, and disappearing ability after the patch effect is complete.

Novel fabrication method of the peritoneal dialysis filter using silk fibroin with urease fixation system.

During the last decade, there has been a great advance in the kidney dialysis system by wearable artificial kidney (WAK) system for end-stage renal disease patients. Uremic solute removal and water regeneration system are the most prerequisite for WAK to work properly. In this study, we designed a filtering membrane system by using immobilized urease silk fibroin filter and evaluated its comparative effectiveness with a PVDF filtering system in peritoneal dialysate regeneration system by urea removal efficacy. We evaluated this membrane's characteristic and performances by conducting SEM-EDX analyze, water-binding abilities and porosity test, removal abilities of urea, cytotoxicity assay and enzyme activity assay. Under the condition for optimization of urease, the percentage removal of urea was about 40% and 60% in 50 mg/dL urea solution by urease immobilized PVDF and silk fibroin scaffolds, respectively. The batch experimental result showed that immobilized filter removed more than 50% of urea in 50 mg/dL urea solution. In addition silk fibroin with urease filter removed 90 percent of urea in the peritoneal dialysate after 24 h filtration. We suggest that silk fibroin with urease fixation filter can be used more effectively for peritoneal dialysate regeneration system, which have hydrophilic property and prolonged enzyme activity. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2136-2144, 2017.

Three dimensional poly(ε-caprolactone) and silk fibroin nanocomposite fibrous matrix for artificial dermis.

Ideal dermal substitutes should have comparable physicochemical and biological properties to the natural skin tissue. In this study, we report a novel strategy to "engineer" controlled 3D nanocomposite fibrous matrix of poly(ε-caprolactone) (PCL) and silk fibroin (SF) for an artificial dermis application. Using a custom-designed cold-plate electrospinning and automatic magnet agitation system, up to 6mm of the thickness was achieved resulting from the accumulation of ice crystal layers on the PCL nanofibers surface-modified with the SF particles. The sacrificed ice crystals induced interconnected macro-pores ranging from tens to hundreds µm. The agitation system introduced uniform distribution of the SF protein within/on the nanofibers, preventing the particles from precipitation and agglomeration. NIH 3T3 fibroblasts proliferated in vitro on the PCL and PCL/SF scaffolds for 7days, but there was no statistical difference between the groups. Conversely, In vivo rat model studies revealed that the wound healing rate and collagen deposition increased with the SF content within the nanocomposites. The unique 3D construct with the PCL/SF nanocomposite fibers provided desirable spatial cues, surface topography, and surface chemistry for the native cells to infiltrate into the scaffolds. The wound healing potential of the nanocomposites was comparable to the commercial Matriderm® artificial dermis.

Three-dimensional electrospun silk-fibroin nanofiber for skin tissue engineering.

Tissue-engineered skin substitutes may offer an effective therapeutic option for the treatment of patients with skin damages. In this study, a novel three-dimensional (3D) scaffold composed of electrospun silk fibroin (SF) nanofiber was fabricated using electrospinning with the addition of NaCl crystals. It has well known that the electrospun SF nanofibers were excellent scaffold for tissue. However, it is generally difficult for cells to infiltrate the electrospun silk fibroin due to its small pore size. To resolve this problem, we dropped the NaCl crystals above the rotating collector, which become incorporated into the nanofibers. Three methods (freeze-drying, salt-leaching, and electrospinning with NaCl) for fabrication of SF scaffolds were compared to the difference of their characteristics using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), mechanical strength, porosity, swelling abilities, and cell proliferation. Additionally, using air-liquid culture system, keratinocytes were co-cultured with fibroblasts in each type of SF scaffolds to construct an artificial bilayer skin in vitro. In our experimental results, histologic findings in only electrospun SF scaffolds showed more proliferation of fibroblasts in deep layer and more differentiation of keratinocytes in superficial layer. The present study suggests that 3D electrospun SF scaffolds might be a suitable for skin tissue engineering.

Fabrication of 3D porous SF/ß-TCP hybrid scaffolds for bone tissue reconstruction.

Bio-ceramic is a biomaterial actively studied in the field of bone tissue engineering. But, only certain ceramic materials can resolve the corrosion problem and possess the biological affinity of conventional metal biomaterials. Therefore, the recent development of composites of hybrid composites and polymers has been widely studied. In this study, we aimed to select the best scaffold of silk fibroin and ß-TCP hybrid for bone tissue engineering. We fabricated three groups of scaffold such as SF (silk fibroin scaffold), GS (silk fibroin/small granule size of ß-TCP scaffold) and GM (silk fibroin/medium granule size of ß-TCP scaffold), and we compared the characteristics of each group. During characterization of the scaffold, we used scanning electron microscopy (SEM) and a Fourier transform infrared spectroscopy (FTIR) for structural analysis. We compared the physiological properties of the scaffold regarding the swelling ratio, water uptake and porosity. To evaluate the mechanical properties, we examined the compressive strength of the scaffold. During in vitro testing, we evaluated cell attachment and cell proliferation (CCK-8). Finally, we confirmed in vivo new bone regeneration from the implanted scaffolds using histological staining and micro-CT. From these evaluations, the fabricated scaffold demonstrated high porosity with good inter-pore connectivity, showed good biocompatibility and high compressive strength and modulus. In particular, the present study indicates that the GM scaffold using ß-TCP accelerates new bone regeneration of implanted scaffolds. Accordingly, our scaffold is expected to act a useful application in the field of bone tissue engineering. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1779-1787, 2016.

Wound healing effect of electrospun silk fibroin nanomatrix in burn-model.

Silk fibroin has recently become an important biomaterial for tissue engineering application. In this study, silk fibroin nanomatrix was fabricated by electrospinning and evaluated as wound dressing material in a burn rat model. The wound size reduction, histological examination, and the quantification of transforming growth factor TGF-ß1 and interleukin IL-1α, 6, and 10 were measured to evaluate the healing effects. The silk fibroin nanomatrix treatment exhibited effective performance in decreasing the wound size and epithelialization. Histological finding also revealed that the deposition of collagen in the dermis was organized by covering the wound area in the silk fibroin nanomatrix treated group. The expression level of pro-inflammatory cytokine (IL-1α) was significantly reduced in the injured skin following the silk fibroin nanomatrix treatment compared to the medical gauze (control) at 7 days after burn. Also, the expression level of TGF-ß1 in the wound treated with silk fibroin nanomatrix peaked 21-days post-treatment whereas expression level of TGF-ß1 was highest at day 7 in the gauze treated group. In conclusion, this data demonstrates that silk fibroin nanomatrix enhances the burn wound healing, suggesting it is a good candidate for burn wound treatment.

Fabrication of duck's feet collagen-silk hybrid biomaterial for tissue engineering.

Collagen constituting the extracellular matrix has been widely used as biocompatible material for human use. In this study, we have selected duck's feet for extracting collagen. A simple method not utilizing harsh chemical had been employed to extract collagen from duck's feet. We fabricated duck's feet collagen/silk hybrid scaffold for the purpose of modifying the degradation rate of duck's feet collagen. This study suggests that extracted collagen from duck's feet is biocompatible and resembles collagen extracted from porcine which is commercially used. Duck's feet collagen is also economically feasible and it could therefore be a good candidate as a tissue engineering material. Further, addition of silk to fabricate a duck's feet collagen/silk hybrid scaffold could enhance the biostability of duck's feet collagen scaffold. Duck's feet collagen/silk scaffold increased the cell viability compared to silk alone. Animal studies also showed that duck's feet collagen/silk scaffold was more biocompatible than silk alone and more biostable than duck's feet or porcine collagen alone. Additionally, the results revealed that duck's feet collagen/silk hybrid scaffold had high porosity, cell infiltration and proliferation. We suggest that duck's feet collagen/silk hybrid scaffold could be used as a dermal substitution for full thickness skin defects.

Novel fabrication of fluorescent silk utilized in biotechnological and medical applications.

Silk fibroin (SF) is a natural polymer widely used and studied for diverse applications in the biomedical field. Recently, genetically modified silks, particularly fluorescent SF fibers, were reported to have been produced from transgenic silkworms. However, they are currently limited to textile manufacturing. To expand the use of transgenic silkworms for biomedical applications, a solution form of fluorescent SF needed to be developed. Here, we describe a novel method of preparing a fluorescent SF solution and demonstrate long-term fluorescent function up to one year after subcutaneous insertion. We also show that fluorescent SF labeled p53 antibodies clearly identify HeLa cells, indicating the applicability of fluorescent SF to cancer detection and bio-imaging. Furthermore, we demonstrate the intraoperative use of fluorescent SF in an animal model to detect a small esophageal perforation (0.5 mm). This study suggests how fluorescent SF biomaterials can be applied in biotechnology and clinical medicine.