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Additive manufacturing is a promising technique in tissue engineering, as it enables truly individualized implants to be made to fit a particular defect. As previously shown, a feasible strategy to produce complex multicellular tissues is to deposit different small interfering RNA (siRNA) in porous implants that are subsequently sutured together. In this study, an additive manufacturing strategy to deposit carbohydrate hydrogels containing different siRNAs is applied into an implant, in a spatially controlled manner. When the obtained structures are seeded with mesenchymal stem (stromal) cells, the selected siRNAs are delivered to the cells and induces specific and localized gene silencing. Here, it is demonstrated how to replicate part of a patient's spinal cord from a computed tomography scan, using an additive manufacturing technique to produce an implant with compartmentalized siRNAs in the locations corresponding to distinct tissue. Hydrogel solutions loaded with different siRNA can be co-printed together with polycaprolactone that acts as rigid mechanical support to the hydrogel. This study demonstrates a new route for the production of 3D functionalized, individualized implants which may provide great clinical benefit. [ABSTRACT FROM AUTHOR]

AbstractObjectiveMethodsResultsConclusionAnastomotic leakage is a severe complication with multifactorial aetiology, including impaired tissue oxygenation, infection, inflammation, and anastomotic tension. Reinforcement with poly-ε-caprolactone (PCL) scaffold incorporated in a stapled intestinal anastomosis has demonstrated a significant increase in the anastomotic tensile strength. This study aimed to investigate whether incorporation of the scaffold would influence tensile strength with induced ischemia compared to normal blood perfusion.Eighteen pigs were randomly allocated into an intervention group with a induced relative reduction in blood perfusion to 30% at the anastomotic area and a control group with normal perfusion controlled by quantitative fluorescence angiography. Each pig recieved two stapled small intestinal anastomoses, one with a PCL scaffold incorporated and one without. On postoperative day five, the anastomoses were subjected to a maximal tensile strength test (MATS) and a histopathological analysis. Tensile strength was measured at three events: when a serosal tear became visible (MATS-1), at transmural rupture (MATS-2), and at maximum load before the load-strain curve dropped (MATS-3).In the intervention group, MATS-1 was significantly higher in scaffold-reinforced anastomoses compared to controls (7.9 ± 4.2N and 4.4 ± 2.5N, p < 0.02). The same tendency was found for MATS-2 and MATS-3, with statistically significant differences after adjusting for adhesion grade (p < 0.05). Histological analysis revealed no significant differences in wound healing between groups.Incorporating a PCL scaffold in a stapled small intestinal anastomosis with induced ischemia improved anastomotic tensile strength. [ABSTRACT FROM AUTHOR]

Elaeocarpus hainanensis has been used in the Oriental medicine but there are very few studies on its phytochemical profile. Our ongoing research on chemical constituents from Elaeocarpus plants in Vietnam led to the isolation of a new oleanane-type saponin from the aerial part of E. hainanensis. Its structure was identified as 1α-hydroxy-olean-11-oxo-12-en-3-O-β-L-arabinopyranoside (1) on the basis of extensive chemical and spectroscopic analyses including NMR and MS spectra. The occurence of the unique oleananetype saponins in E. hainanensis contributed to impact phytochemical profile associated with chemotaxanomy meaning of the title plant. [ABSTRACT FROM AUTHOR]

Background: Medicinal plants are widely used for the treatment of different infectious diseases. Infectious diseases caused by bacteria have a large impact on public health. This study aimed to determine the in vitro antibacterial activity of the medicinal plants traditionally used in Vietnam against the bacterial strains associated with infectious diseases., Methods: Methanol extracts of twelve Vietnamese medicinal plants were tested for their antibacterial activity against five bacterial species including Gram-positive bacteria (Bacillus cereus, Bacillus subtilis, and Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) using the broth microdilution method., Results: All the plant extracts showed antibacterial activity, especially against Gram-positive bacteria (Bacillus cereus, Bacillus subtilis, and Staphylococcus aureus). Baeckea frutescens extract revealed a potent activity against the Gram-positive bacteria with the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of 62.5 μg/ml. High activity against all the three Gram-positive bacteria was also observed for the extracts of Cratoxylum formosum ssp. pruniflorum, Pogostemon cablin, and Pedilanthus tithymaloides with MICs of 125, 125 and 250 μg/ml and MBCs of 125-250, 125-250 and 250-500 μg/ml, respectively. The extracts of C. formosum ssp. pruniflorum and P. tithymaloides showed a broad-spectrum antibacterial activity against all the bacteria tested with the MICs of 125-2,000 μg/ml., Conclusion: This study indicates clear evidence supporting the traditional use of the plants in treating infectious diseases related to bacteria. In particular, these plant species showed moderate to high antibacterial activity against the Gram-positive bacteria tested.