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Herein, gellan gum (GG), a nature-derived polysaccharide, was applied to combine fluorescein isothiocyanate (FITC) to fabricate a bio-imaging material. The synthesis process of the FITC grafted GG (GG-F) and manufacturing method of GG-F scaffolds are presented. Chemical, physicochemical, and mechanical properties were characterized. In vitro study and in vivo study by implanting the GG-F scaffolds under the subcutaneous area of the nude mice were carried out to verify biocompatibility and safety of the material. The emission of the FITC was confirmed with high-resolution confocal laser scanning microscope (SR CLMS) and fluorescence in vivo imaging (FOBI). The results exhibited well-synthesized GG-F and the manufactured GG-F scaffolds showed similar property of GG scaffolds which confirms that the chemical modification does not affect the property of GG scaffolds. The in vitro and in vivo study exhibited biocompatibility of the GG-F material. Overall, the properly blended GG-F in GG did not influence the characteristics of the pristine GG except for the chemical property. Therefore, the GG-F can be applied for the future analysis in verifying the mechanism of GG characters and can be a promising candidate for bio-imaging.

In this study, 6-(6-aminohexyl) amino-6-deoxy-β-cyclodextrin-gellan gum complex hydrogel (HCD-GG) was developed to enhance the affinity of anti-inflammatory drug dexamethasone (Dx), improve chondrogenesis, and decrease the inflammatory response. The modified chemical structure was confirmed by NMR and FTIR. Mechanical and physicochemical properties were characterized by performing viscosity study, compression test, injection force test, swelling kinetic, weight loss, and morphological study. The release profile of the drug-loaded hydrogels was analyzed to confirm the affinity of the hydrophobic drugs and the matrix and characterize cumulative release. In vitro test was carried out with MTT assay, live/dead staining, glycosaminoglycan (GAGs) content, double-stranded DNA (dsDNA) content, morphological analysis, histology, and gene expression. In vivo experiment was conducted by implanting the samples under a subcutaneous area of SPD rat and cartilage defected rabbit model. The results displayed successfully synthesized HCD-GG. The gelation temperature of the modified hydrogels was decreased while the mechanical property was improved when the drug was loaded in the modified hydrogel. Swelling and degradation kinetics resulted in a higher level compared to the pristine GG but was a sufficient level to support drugs and cells. The affinity and release rate of the drug was higher in the HCD-GG group which shows an improved drug delivery system of the GG-based material. The microenvironment provided a suitable environment for cells to grow. Also, chondrogenesis was affected by the existence of Dx and microenvironment, resulting in higher expression levels of cartilage-related genes while the expression of the inflammation mediators decreased when the Dx was loaded. In vivo study showed an improved anti-inflammatory response in the drug-loaded hydrogel. Furthermore, the cartilage defected rabbit model showed an enhanced regenerative effect when the Dx@HCD-GG was implanted. These results suggest that HCD-GG and Dx@HCD-GG have the potential for cartilage regeneration along with multiple applications in tissue engineering and regenerative medicine.

Gellan gum (GG), a nature-derived polysaccharide, is one of the materials widely used in cartilage tissue engineering (TE). Glycol chitosan (GC), a derivative of chitosan, is a water-soluble natural polymer that has excellent biocompatibility and biodegradability as well as cell adhesion. Herein, GG was physically blended with GC to enhance the mechanical properties and microenvironment of the GG to apply in cartilage TE. The study was conducted with a hydrogel model which is similar to the extracellular matrix (ECM) of cartilage tissue. The physicochemical studies were carried out with morphological study, swelling ratio, weight loss, and sol fraction. The mechanical characterization was conducted with compression test and rheological study to confirm availability in cartilage TE material. Furthermore, in vitro studies such as morphology investigation, viability assay, GAG content, qRT-PCR, and histological study were performed to verify biocompatibility and chondrogenesis of the material. The mechanical and biological properties improved with a proper amount of GC. Overall results verify the potential of the material and can be further used for the cartilage TE.

Osteochondral (OC) lesions can occur in the knee and ankle. Such lesions induce a fracture in the cartilage protecting the bone joints. Cartilage tissue shows limited self-regeneration ability, hence the tissue is avascular and lack of vascular innervation, while the bone is a unique organ with the capacity to self-repair of small defects. In this present study, we have prepared a scaffold using demineralized bone powder (DBP) extracted from Gallus gallus var domesticus (GD), and Gellan gum (GG) for OC tissue regeneration. They were characterized for their chemical, physical, mechanical and biological properties using different available techniques, in vitro bioactivity was performed in simulated body fluid for 14 days confirming the formation of bone-like apatite. The in vitro biocompatibility was analyzed using chondrocyte cells and osteogenic and chondrogenic marker gene expression using RT-PCR, in vivo experiments performed by implanting scaffold in rabbit and characterized by histology and immunofluorescent stainings. The obtained results indicated that the prepared pores scaffold was biocompatible, and promote OC regeneration and integration of newly formed tissues with the host tissues in a rabbit. The prepared 1% DBP/GG scaffold can be used as a potential and promising alternate material for OC regeneration.

The prevalence of bone-related diseases has increased, the population growth as a result of the aging phenomenon requires more effective treatments for regeneration of bone defect. Although an autogenous bone graft was used in traditional operation method, they are very inefficient in current bone defect surgery and very difficult to gather the required amount of bone for operation. It is becoming a gradually growing disease, hence there is a need for developing a new method for preparing biomimetic scaffolds. DBP (demineralized bone powder), a potent bone regeneration material, has a trace amount of ions and bone mineral component. Especially, GD (Gallus gallus var domesticus) DBP has a unique property, which has melanin, for strengthening bones, increasing ALP activity and bone mineralization, compared to other available biomaterials. For that reason, GD DBP was combined with GG (gellan gum). The material was characterized in vitro and in vivo rat model. The first priority in this work was given to assessing the attachment and proliferation rates of BMSCs following the in vivo experiment in rats. The results of 1% sample showed better osteogenic effects that can be used in clinical application after studying in larger animals for better bone regeneration and tissue engineering.

Retinal pigment epithelium (RPE) plays an important role in maintaining normal function and visual function of the retina, and the degeneration of RPE causes various retinal degenerative diseases. Currently, there is a lack of effective treatment for this, and it is being studied to produce a suitable scaffold for cell transplantation. In this experiment, Polyethylene glycol (PEG)/Gellan Gum (GG) hydrogel was prepared by adding harmless PEG and gellan gum, which is a biocompatible, degradable and widely used in modern tissue engineering. PEG/GG hydrogel was prepared with 0, 1, 3, 5 wt% PEG/GG according to the concentration of PEG, and ARPE-19 cells were used to confirm the cell attachment environment. As a result, it showed superior biocompatibility (>90%), cell adhesion and improved cell growth compared to gellan gum hydrogel. In addition, RT-PCR was used to confirm RPE-specific gene expression, and the result showed that it was positively influenced. As a result, it was observed that PEG/GG hydrogel promotes retinal regeneration compared to pure gellan gum. 3 wt% PEG/GG could be used as an alternative for retinal regeneration.

Tissue engineered scaffolds, made of natural derived materials, have the potential to be used in bone regeneration fields due to the biocompatible and biodegradable features. In this study, we propose duck's feet-derived collagen (DC) sponges blended with hydroxyapatite (HAp), incorporated with different concentrations of silymarin (Smn), for improved bone regeneration. The morphological and structural properties of DC/HAp and DC/HAp loaded with 25, 50 and 100 μM of Smn sponges were analyzed using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). In vitro evaluations were carried out on rabbit bone marrow stem cells (rBMSCs) using MTT assay for cell proliferation, ALP assay for osteogenic differentiation and reverse transcription-polymerase chain reaction (RT-PCR) for expression of mRNAs. For the evaluation of new bone formation in vivo, histological analysis and micro computed tomography (μCT) were used. Preliminary results, on Smn/DC/HAp morphology and mechanical properties, showed an interconnected porosity suitable for cells ingrowth and a higher compressive strength with the presence of Smn. Similarly, the cells proliferation and ALP activity modulation were positively influenced by the Smn content. Especially, the 100 μM Smn/DC/HAp sponge efficiently enhances the rBMSCs adhesion, growth and gene expression of osteogenic markers. The enhanced osteoinductive effects of sponges blended with Smn were confirmed using μ-CT and histological evaluations. In conclusion, results suggest that collagen sponges represent an excellent environment for cells growth and proliferation, while Smn plays an important role to improve materials osteogenic properties.

The retinal pigment epithelium (RPE) plays a significant role in retaining structural integrity of eye. Factors such as reduction in cell regeneration due to aging and physical injury pose a major hurdle in RPE regeneration. In this study, we exploited the use of alginate (AGT) incorporated with Curcumin (CCI) forming a hydrogel based system CCI/AGT. The fabricated hydrogel could anchor RPE cell in it. In vitro cell analysis revealed that the CCI/AGT hydrogel shows good biocompatibility, enhanced cell growth ability and higher ECM formation compared to the pure AGT hydrogel. In particular, the presence of CCI in the hydrogels enhances the cells proliferation of the 23% respect to the pure alginate. Also the expression of crucial genes for retina functions and matrix production were positively affected by CCI presence, with an increment of 45% for RPE65, 32% for CRALBP and 26% for Collagen type 1. In vitro tests demonstrated the potential application of CCI/AGT hydrogels for transplantation under the sub-retinal space acting as a cell delivery vehicle and also their capability to provide an appropriate environment for RPE regeneration. These results suggest that CCI/AGT hydrogel could be translated into a potential surgical graft for biological implantation of retinal tissue engineering.

Scaffolds, used for tissue regeneration are important to preserve their function and morphology during tissue healing. Especially, scaffolds for bone tissue engineering should have high mechanical properties to endure load of bone. Silk fibroin (SF) from Bombyx mori silk cocoon has potency as a type of biomaterials in the tissue engineering. β-tricalcium phosphate (β-TCP) as a type of bioceramics is also critical as biomaterials for bone regeneration because of its biocompatibility, osteoconductivity, and mechanical strength. The aim of this study was to fabricate three-dimensional SF/β-TCP scaffolds and access its availability for bone grafts through in vitro and in vivo test. The scaffolds were fabricated in each different ratios of SF and β-TCP (100:0, 75:25, 50:50, 25:75). The characterizations of scaffolds were conducted by FT-IR, compressive strength, porosity, and SEM. The in vitro and in vivo tests were carried out by MTT, ALP, RT-PCR, SEM, μ-CT, and histological staining. We found that the SF/β-TCP scaffolds have high mechanical strength and appropriate porosity for bone tissue engineering. The study showed that SF/β-TCP (75:25) scaffold exhibited the highest osteogenesis compared with other scaffolds. The results suggested that SF/β-TCP (75:25) scaffold can be applied as one of potential bone grafts for bone 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.

The ZnO nanoneedles (ZNNs) were grown in large quantity by thermal evaporation technique on non-catalytic Si (100) substrates and used as an effective photocatalyst for photocatalytic degradation of methyl orange dye (MO). The detailed characteristics of ZNNs confirmed that the synthesized nanostructures are grown in high density and exhibit well-crystallinity with good optical properties. The photocatalytic properties of ZNNs were investigated under UV light irradiation. A fast decomposition of the MO dye was observed with a degradation rate of ~95.4% within 140 min.

The purpose of this study is to produce injectable taurine (Tr)-loaded alginate (Agn) hydrogel for age-related macular degeneration (AMD) treatment by inducing the regeneration of RPE (retinal pigment epithelium) cells. Porosity and swelling ratio were measured to evaluate the mechanical properties of the hydrogels, and Fourier transform infrared spectroscopy (FTIR) was used to evaluate the physical and chemical properties. RPE cells extracted from the pigmented epithelium of rabbits were encapsulated in the Tr/Agn hydrogels. Cells proliferation and migration were improved in Tr/Agn hydrogels with an enhanced expression of RPE-specific genes including RPE65, CRALBP, NPR-A, MITF and collagen type I and II. In vivo tests demonstrated the excellent biocompatibility and biodegradability without inflammatory response by the host when implanted with the hydrogel. Moreover, when the Tr/Agn hydrogels were injected into the sub-retinal space, high adhesion of RPE cells and retinal regeneration were confirmed. These results demonstrated a potential role of injectable Tr/Agn hydrogels as potential therapeutic tools for the treatment of retinal diseases, including AMD.

There are two distinct subtypes of autoimmune pancreatitis (AIP): type 1 and type 2. Type 1 AIP is the pancreatic manifestation of systemic fibroinflammatory disease, which is named as IgG4-related disease. On the other hand, type 2 AIP is a pancreatic disorder that is not associated with IgG4. Type 1 and type 2 AIP have different clinical profiles and histologic findings. We present a 22-year-old man who has been diagnosed as type 1 AIP with histologically proven granulocytic epithelial lesion after surgical resection for pancreatic head mass. Since the patient had no pancreatic duct narrowing, elevation of serum IgG4, and other organ involvement, it was very difficult to diagnose preoperatively. This is a rare and interesting case in which histologic features of type 1 and type 2 AIP coexist.

Methods: A retrospective 1:2 matched cohort study was performed to evaluate the risk of PTE in patient with gemcitabinebased chemotherapy for pancreatic cancer. Clinical parameter including rate of increment of platelet count (Inc-Plt) was checked in PTE group and non-PTE group. Inc-Plt was defined as the difference of platelet count from new cycle day 1 to last cycle day 15. The rate of Inc-Plt was defined as the rate of increased platelet count at new cycle day 1 compared with previous cycle day 15. Each patient in PTE group was matched with two patients in the non-PTE group.