Tzong-Fu Kuo

The main aim of this study is to investigate the therapeutic efficacy of direct intra-articular injection of bone-marrow-derived stem/stromal cells (BMSCs) and the adjuvant role of hyaluronic acid (HA) in facilitating rabbit articular cartilage repair. First, rabbit BMSCs were treated with a medium containing different concentrations of HA. Later, HA’s influence on BMSCs’ CD44 expression, cell viability, extracellular glycosaminoglycan (GAG) synthesis, and chondrogenic gene expression was evaluated during seven-day cultivation. For the in vivo experiment, 24 rabbits were used for animal experiments and 6 rabbits were randomly allocated to each group. Briefly, chondral defects were created at the medial femoral condyle; group 1 was left untreated, group 2 was injected with HA, group 3 was transplanted with 3 × 10⁶ BMSCs, and group 4 was transplanted with 3 × 10⁶ BMSCs suspended in HA. Twelve weeks post-treatment, the repair outcome in each group was assessed and compared both macroscopically and microscopically. Results showed that HA treatment can promote cellular CD44 expression. However, the proliferation rate of BMSCs was downregulated when treated with 1 mg/mL (3.26 ± 0.03, p = 0.0002) and 2 mg/mL (2.61 ± 0.04, p = 0.0001) of HA compared to the control group (3.49 ± 0.05). In contrast, 2 mg/mL (2.86 ± 0.3) of HA treatment successfully promoted normalized GAG expression compared to the control group (1.88 ± 0.06) (p = 0.0009). The type II collagen gene expression of cultured BMSCs was significantly higher in BMSCs treated with 2 mg/mL of HA (p = 0.0077). In the in vivo experiment, chondral defects treated with combined BMSC and HA injection demonstrated better healing outcomes than BMSC or HA treatment alone in terms of gross grading and histological scores. In conclusion, this study helps delineate the role of HA as a chondrogenic adjuvant in augmenting the effectiveness of stem-cell-based injection therapy for in vivo cartilage repair. From a translational perspective, the combination of HA and BMSCs is a convenient, ready-to-use, and effective formulation that can improve the therapeutic efficacy of stem-cell-based therapies.

The use of mesenchymal stem cells (MSCs), which can be differentiated into chondrocytes under specific conditions, has been proposed for the treatment of cartilage defects. Blood‐derived platelet‐rich fibrin releasate (PRFr), which is rich in growth factors and cytokines, may improve cartilage regeneration. In this study, the therapeutic effects of PRFr in combination with bone marrow‐derived MSCs for articular cartilage regeneration were evaluated in a rabbit model. Critical osteochondral defects were surgically created in the femoral condyle of the rabbits, and 3 × 10⁶ of MSCs, 0.8 mL of PRFr, or a combination of MSCs and PRFr were injected intra‐articularly and one week after first administration. The animals were sacrificed 12 weeks postoperatively, and the regenerated cartilages were assessed by gross inspection and histological examination. No treatment‐related adverse events were noted in any of the rabbits. The size of the defect decreased and the volume of regenerated cartilage increased in the medial femoral condyles of the MSCs + PRFr group. Relative to the MSCs or PRFr group, histological examination demonstrated that the MSCs + PRFr group had thicker hyaline‐like cartilaginous tissue with normal glycosaminoglycan production. Grading scores revealed that MSCs + PRFr injection had better matrix, cell distribution, and surface indices than other groups. The results showed that intra‐articular injections of MSCs + PRFr into the knee can reduce cartilage defects by regenerating hyaline‐like cartilage without adverse events. This approach may provide an alternative method of autologous chondrocyte implantation to repair cartilage defects with an unlimited source of cells and releasate. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1536–1543, 2017.

Background: Tradescantia albiflora (TA) Kunth (Commelinaceae) has been used for treating gout and hyperuricemia as folklore remedies in Taiwan. Therefore, it is worthwhile to study the effect of TA extracts on lowering uric acid activity. The hypouricemic effects of TA extracts on potassium oxonate (PO)-induced acute hyperuricemia were investigated for the first time. Materials and Methods: All treatments at the same volume (1 ml) were orally administered to the abdominal cavity of PO-induced hyperuricemic rats. One milliliter of TA extract in n-hexane (HE), ethyl acetate (EA), n-butanol (BuOH), and water fractions has 0.28, 0.21, 0.28, and 1.03 mg TA, respectively; and the plasma uric acid (P_UA) level was measured for a consecutive 4 h after administration. Results: All four fractions' extracts derived from TA were observed to significantly reduce P_UAcompared with the PO group. The EA-soluble fraction (TA-EA) exhibited the best xanthine oxidase (XO) inhibitory activity. Following column chromatography, 12 phytochemicals were isolated and identified from the EA fraction. The IC₅₀values of isolated phytochemicals indicated that bracteanolide A (AR11) showed the remarkable XO inhibitory effect (IC₅₀value of 76.4 μg/ml). These findings showed that the in vivo hypouricemic effect in hyperuricemic rats was consistent with in vitro XO inhibitory activity, indicating that TA extracts and derived phytochemicals could be potential candidates as hypouricemic agents. SUMMARY

Background: Longan is a fruit tree known to contain many phenolic components, which are capable of protecting people from oxidative damage through an anti-inflammatory mechanism. It may be also worthwhile to study the effect on lowering uric acid activity. Materials and Methods: This study investigates the lowering of uric acid using longan extracts, including flowers, pericarps, seeds, leaves, and twigs, on potassium-oxonate-induced hyperuricemia mice and its inhibitory actions against xanthine oxidase (XO) activities. Results: The findings revealed that ethyl acetate fraction of longan extracts exhibited strong XO-inhibitory activity, and the flower extracts (IC₅₀ = 115.8 μg/mL) revealed more potent XO-inhibitory activity to those of pericarps (118.9 μg/mL), twigs (125.3 μg/mL), seeds (262.5 μg/mL), and leaves (331.1 μg/mL) in vitro. In addition, different dosages of longan extract (50–100 mg/kg) were administered to hyperuricemic mice. The lowering effect of longan extracts on uric acid at 75 mg/kg markedly reduced plasma uric acid levels in decreasing order: Flowers (80%) > seeds (72%) > pericarps (64%) > twigs (59%) > leaves (41%), compared with allopurinol (89%). Finally, 10 isolated phytochemicals from longan flowers were then examined in vitro. The results indicated that proanthocyanidin A2 and acetonylgeraniin A significantly inhibited XO activity in vitro. This is the first report providing new insights into the urate-reducing effect of phenolic dimer and hydrolyzable tannin, which can be developed to potential hypouricemic agents. SUMMARY

The purpose of this study was to demonstrate the feasibility of whole‐tooth regeneration using a tooth germ‐like construct. Dental pulp from upper incisors, canines, premolars, and molars were extracted from sexually mature miniature pigs. Pulp tissues were cultured and expanded in vitro to obtain dental pulp stem cells (DPSCs), and cells were differentiated into odontoblasts and osteoblasts. Epithelial cells were isolated from gingival epithelium. The epithelial cells, odontoblasts, and osteoblasts were seeded onto the surface, upper, and lower layers, respectively, of a bioactive scaffold. The lower first and second molar tooth germs were removed bilaterally and the layered cell/scaffold constructs were transplanted to the mandibular alveolar socket of a pig. At 13.5 months postimplantation, seven of eight pigs developed two teeth with crown, root, and pulp structures. Enamel‐like tissues, dentin, cementum, odontoblasts, and periodontal tissues were found upon histological inspection. The regenerated tooth expressed dentin matrix protein‐1 and osteopontin. All pigs had regenerated molar teeth regardless of the original tooth used to procure the DPSCs. Pigs that had tooth germs removed or who received empty scaffolds did not develop teeth. Although periodontal ligaments were generated, ankylosis was found in some animals. This study revealed that implantation of a tooth germ‐like structure generated a complete tooth with a high success rate. The implant location may influence the morphology of the regenerated tooth.

Amoxicillin is an antibiotic which belongs to the group of penicillins. It is approved in Taiwan for treating bacterial infections caused by Streptococcus sp. and Photobacterium sp. in anguilliformes, perciformes and salmoniformes. The pharmacokinetics of amoxicillin were determined in pompano following oral administration of a single dose of 40 mg/kg. Residue studies were performed to determine residues in liver and kidney tissues of healthy fish after oral gavage of amoxicillin at a daily dose of 40 mg/kg for five consecutive days. Amoxicillin residues were analyzed by HPLC using Hypersil-100 C18 column (150 mm × 4.6 mm i.d.) and mobile phase consists of 10 mM K₂HPO₄(pH 8.5) with acetonitrile (80:20, v/v), at a flow rate of 1 mL/min. The effluent was monitored using a fluorescence detector set as 358 and 440 nm as excitation and emission wavelengths. Following a single oral dose, amoxicillin residues in 0.5 h post-dosing pompano were at a maximum of 6.17 μg/g in liver and 4.27 μg/g in kidney; the concentration of amoxicillin in liver and kidney declined with half-lives of 18.3 and 12.0 h. Amoxicillin residues in pompano liver and kidney tissues were proved to be under the MRL, 0.5 ug/g (liver and kidney) after a withdrawal period of five days.

Danggui Buxue Tang (DBT) is a traditional Chinese herbal decoction containing Radix Astragali and Radix Angelicae sinensis. Pharmacological results indicate that DBT can stimulate bone cell proliferation and differentiation. The aim of the study was to investigate the efficacy of adding DBT to bone substitutes on bone regeneration following bone injury. DBT was incorporated into porous composites (GGT) made from genipin-crosslinked gelatin and β-triclacium phosphates as bone substitutes (GGTDBT). The biological response of mouse calvarial bone to these composites was evaluated by in vivo imaging systems (IVIS), micro-computed tomography (micro-CT), and histology analysis. IVIS images revealed a stronger fluorescent signal in GGTDBT-treated defect than in GGT-treated defect at 8 weeks after implantation. Micro-CT analysis demonstrated that the level of repair from week 4 to 8 increased from 42.1% to 71.2% at the sites treated with GGTDBT, while that increased from 33.2% to 54.1% at GGT-treated sites. These findings suggest that the GGTDBT stimulates the innate regenerative capacity of bone, supporting their use in bone tissue regeneration.

Danofloxacin is an antibacterial drug of the fluoroquinolone group developed for therapeutic purposes in veterinary medicine. The studies described here include investigations of the residues following a single dose or multiple doses of danofloxacin. Residue depletion studies were performed to determine residues in plasma and tissues of saltwater tilapia fish (Oreochromis mossambicus) after a single oral administration of danofloxacin at the dose of 10 mg/kg body weight and also after daily dose of 10 mg/kg body weight for five consecutive days. Danofloxacin residues were analyzed by HPLC with fluorescence detection. Following a single oral dose, danofloxacin residues in 6 h postdosing tilapia were at a maximum of 1.44, 12.48, and 13.18 μg/g in serum, liver, and kidney samples, respectively, while a peak muscle concentration of 2.15 μg/g was reached at 12 h. From single-dose data, the concentration of danofloxacin in serum, muscle, liver, and kidney samples declined with half-lives of 29, 34, 49, and 44 h, respectively. Based on the maximum residue level (MRL) of 0.1 μg/g in edible tissue for fin fish, the withdrawal times of danofloxacin in muscle were estimated to fall below the MRL after a withdrawal period of 21 days following the multiple-dose administration. These results may be helpful to regulatory agencies as they determine what tissues should be monitored to ensure that the established residue safety tolerance levels are not exceeded.