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Lacroix Hahn posted an update 6 months, 3 weeks ago
The physiological O2 microenvironment of mesenchymal stem cells (MSCs) and osteoblasts and the dimensionality of a substrate are known to be important in regulating cell phenotype and function. By providing the physiologically normoxic environments of bone marrow (5%) and matrix (12%), we assessed their potential to maintain stemness, induce osteogenic differentiation, and enhance the material properties in the micropatterned collagen/silk fibroin scaffolds that were produced in 2D or 3D. Expression of osterix (OSX) and vascular endothelial growth factor A (VEGFA) was significantly enhanced in the 3D scaffold in all oxygen environments. #link# At 21% O2, OSX and VEGFA expressions in the 3D scaffold were respectively 13,200 and 270 times higher than those of the 2D scaffold. Markers for assessing stemness were significantly more pronounced on tissue culture polystyrene and 2D scaffold incubated at 5% O2. At 21% O2, we measured significant increases in ultimate tensile strength (p less then 0.0001) and Young’s modulus (p = 0.003) of the 3D scaffold compared to the 2D scaffold, whilst 5% O2 hindered the positive effect of cell seeding on tensile strength. In conclusion, we demonstrated that the 3D culture of MSCs in collagen/silk fibroin scaffolds provided biomimetic cues for bone progenitor cells toward differentiation and enhanced the tensile mechanical properties.The dopamine D2/D3 receptor (D2R/D3R) agonists are used as therapeutics for Parkinson’s disease (PD) and other motor disorders. see more of D3R over D2R is attractive because of D3R’s restricted tissue distribution with potentially fewer side-effects and its putative neuroprotective effect. However, the high sequence homology between the D2R and D3R poses a challenge in the development of D3R selective agonists. To address the ligand selectivity, bitopic ligands were designed and synthesized previously based on a potent D3R-preferential agonist PF592,379 as the primary pharmacophore (PP). This PP was attached to various secondary pharmacophores (SPs) using chemically different linkers. Here, we characterize some of these novel bitopic ligands at both D3R and D2R using BRET-based functional assays. The bitopic ligands showed varying differences in potencies and efficacies. In addition, the chirality of the PP was key to conferring improved D3R potency, selectivity, and G protein signaling bias. In particular, compound AB04-88 exhibited significant D3R over D2R selectivity, and G protein bias at D3R. This bias was consistently observed at various time-points ranging from 8 to 46 min. Together, the structure-activity relationships derived from these functional studies reveal unique pharmacology at D3R and support further evaluation of functionally biased D3R agonists for their therapeutic potential.Pinus needle tea are very popular in Eastern countries such as Japan, Russia, Korea, and China. Pine needle tea is claimed to have significant anti-aging effects, but no clear evidence has supported this until now. In the present study, five undescribed compounds (1-5) as well as seventy-two known compounds were purified and characterized from the bioactive fraction of methanol extracts of P. taiwanensis needles. Most of the isolates were examined for their anti-inflammatory bioactivity by cellular neutrophil model and six compounds (45, 47, 48, 49, 50, and 51) exhibited a significant inhibition on superoxide anion generation and elastase release with IC50 values ranging from 3.3 ± 0.9 to 8.3 ± 0.8 μM. These anti-inflammatory ingredients were subjected to docking computing to evaluate their binding affinity on the ghrelin receptor, which played an important role in regulating metabolism, with anti-aging effects. Compounds 49, 50, and 51 formed a stable complex with the ghrelin receptor via hydrogen bonds and different types of interactions. These results suggest the flavonoids are responsible for the potential anti-aging effects of pine needle tea.Viola canescens Wall. ex. Roxb. is an important but threatened medicinal herb found at 1500-2400 m above mean sea level in the Himalayas. Overexploitation and habitat preference have put the plant under serious threat. Thus, the present study was undertaken to develop an efficient protocol for in vitro propagation via somatic embryogenesis. The results revealed that plant can be regenerated successfully through somatic embryogenesis using leaf derived calli. Regular subculturing of calli on Murashige and Skoog (MS) medium with 2,4-dichlorophenoxyacetic acid (2,4-D)/indole-3-butyric acid (IBA)/kinetin (Kn) and varying combinations of 2,4-D+Kn induced somatic embryogenesis. The maximum average number of somatic embryos (SE) (19.15 ± 2.66) was induced on the medium with 0.15 + 0.05 mg L-1 of 2,4-D and Kn, respectively, and this medium was used as a control. To enhance somatic embryo induction, the control MS medium was supplemented with l-glutamine (200-400 mg L-1) and casein hydrolysate (1-4%). The maximum average number of SE (27.66 ± 2.67) and average mature SE (13.16 ± 3.48) were recorded on the medium having 2 % l-glutamine and 50 mg L-1 casein hydrolysate. The induced SE were asynchronous, so, to foster their maturation, the culture medium (free from growth regulators) was supplemented with abscisic acid (ABA) and silver nitrate (AgNO3). The maximum average number (35.96 ± 3.68) of mature SE was noticed on MS medium supplemented with 1.5 mg L-1 ABA. Mature embryos had two well-developed cotyledons and an elongated hypocotyl root axis. The development of SE into plantlets was significant for embryos matured on the medium with AgNO3 and ABA, with 86.67% and 83.33% conversion on the medium with 0.20 mg L-1 6-benzylaminopurine (BAP). The plantlets thus produced acclimatized in a growth chamber before being transferred to the field, which showed 89.89% survival. The plants were morphologically similar to the mother plant with successful flowering.Recently, nonexposure simple suturing endoscopic full-thickness resection (NESS-EFTR) method was developed to avoid tumor exposure to the peritoneal cavity. The aim of this study is to compare the short-term outcomes of the NESS-EFTR method with those of laparoscopic and endoscopic cooperative surgery (LECS) for gastric subepithelial tumors (SETs). A prospective single-center trial of LECS for gastric SETs was performed from March 2012 to October 2013 with a separate prospective trial of NESS-EFTR performed from August 2015 to June 2017, enrolling 15 patients each. Among the 30 enrolled patients, 14 who underwent LECS and 11 who underwent NESS-EFTR were finally included in the analysis. The rate of complete resection and successful closure was 100% in both groups. The operating time was longer for NESS-EFTR group than for LECS (110 vs. 189 min; p less then 0.0001). There were no postoperative complications except one case of transient fever in the NESS-EFTR group. One patient in the LECS group had peritoneal seeding of gastrointestinal stromal tumor at 17 months postoperatively, and there was no other recurrence.