Osteoinductivity of gelatin/β-tricalcium phosphate sponges loaded with different concentrations of mesenchymal stem cells and bone morphogenetic protein-2 in an equine bone defect model

Fracture is one of the most life-threatening injuries in horses. Fracture repair is often associated with unsatisfactory outcomes and is associated with a high incidence of complications. This study aimed to evaluate the osteogenic effects of gelatin/β-tricalcium phosphate (GT) sponges loaded with different concentrations/ratios of mesenchymal stem cells (MSCs) and bone morphogenetic protein-2 (BMP-2) in an equine bone defect model. Seven thoroughbred horses were used in this study. Eight bone defects were created in the third metatarsal bones of each horse. Then, eight treatments, namely control, GT, GT/M-5, GT/M-6, GT/M-5/B-1, GT/M-5/B-3, GT/M-6/B-1, and GT/M-6/B-3 were applied to the eight different sites in a randomized manner (M-5: 2?×?10⁵ MSCs; M-6: 2?×?10⁶ MSCs; B-1: 1 μg of BMP-2; B-3: 3 μg of BMP-2). Repair of bone defects was assessed by radiography, quantitative computed tomography (QCT), and histopathological evaluation. Radiographic scores and CT values were significantly lower in the control group than in the other groups, while they were significantly higher in the GT/M-5/B-3 and GT/M-6/B-3 groups than in the other groups. The amount of mature compact bone filling the defects was greater in the GT/M-5/B-3 and GT/M-6/B-3 groups than in the other groups. The present study demonstrated that the GT sponge loaded with MSCs and BMP-2 promoted bone regeneration in an equine bone defect model. The GT/MSC/BMP-2 described here may be useful for treating horses with bone injuries.     

Role of small-scale fishing in Kompong Thom Province, Cambodia

ABSTRACT:   Household surveys of small-scale fishing were conducted in Svay Ear and Srey Rangit villages in Kompong Thom Province, Cambodia. Data were collected from 104 of 183 households and 105 of 140 households in Svay Ear and Srey Rangit, respectively. In both villages, almost all households conducted rice cultivation and approximately 75% of them also conducted fishing. Three fishing groups: (i) inside lake; (ii) around lake; and (iii) around village were observed in both villages, according to their main fishing grounds. The inside lake group conduct fishing only in Tonle Sap Lake which is located 30 km away from the villages. The around lake group fish in lakes, marshes and flooded forests adjacent to Tonle Sap Lake, which are more than 5 km from the villages. The around village group collects fish from rice fields and ponds located inside the villages and also in some streams, rivers and lakes adjacent to the villages. The distance to the fishing grounds is less than 5 km from the villages. Most fishing groups were the inside and around lake groups, which occupied 76.0 and 65.7% of Svay Ear and Srey Rangit, respectively. These two groups produced 80.6 and 69.7% of the respective village annual total fish catches. These two groups sold a large portion of their fish catches. Although previous reports indicated that small-scale fishing is for subsistence, present results indicated that small-scale fishing was commercially conducted and fishing was important as an income source.     

Evaluation of a d-Octaarginine-linked polymer as a transfection tool for transient and stable transgene expression in human and murine cell lines

Poly(N-vinylacetamide-co-acrylic acid) coupled with d-octaarginine (VP-R8) promotes the cellular uptake of peptides/proteins in vitro; however, details of the transfection efficacy of VP-R8, such as the cell types possessing high gene transfer, are not known. Herein, we compared the ability of VP-R8 to induce the cellular uptake of plasmid DNA in mouse and human cell lines from different tissues and organs. A green fluorescent protein (GFP)-expression plasmid was used as model genetic material, and fluorescence as an indicator of uptake and plasmid-derived protein expression. Three mouse and three human cell lines were incubated with a mixture of plasmid and VP-R8, and fluorescence analysis were performed two days after transfection. To confirm stable transgene expression, we performed drug selection three days after transfection. A commercially available polymer-based DNA transfection reagent (PTR) was used as the transfection control and standard for comparing transgene expression efficiency. In the case of transient transgene expression, slight-to-moderate GFP expression was observed in all cell lines transfected with plasmid via VP-R8; however, transfection efficiency was lower than using the PTR for gene delivery. In the case of stable transgene expression, VP-R8 promoted drug-resistance acquisition more efficiently than the PTR did. Cells that developed drug resistance after VP-R8-mediated gene transfection expressed GFP more efficiently than cells that developed drug resistance after transfection with the PTR. Thus, VP-R8 shows potential as an in vitro or ex vivo nonviral transfection tool for generating cell lines with stable transgene expression.