Glycyrrhizin could reduce ocular hypertension induced by triamcinolone acetonide in rabbits

Purpose: To evaluate the hypotensive effects of glycyrrhizin (GL) on a rabbit model of ocular hypertension (OH) induced by triamcinolone acetonide (TA). Methods: Forty New Zealand White Rabbits were divided as follows: control (intravitreal injection of sterile saline solution); GL (intravitreal injection of sterile saline solution, then fed with 25mg GL/day); TA (intravitreal TA injection); TA+GL (intravitreal TA injection, then fed with GL) and GL+TA (pre-treated with GL for 3 days, then got TA injection and the following GL treatment). Intraocular pressure (IOP), flash electroretinogram (flash ERG) and flash visual evoked potential (flash VEP) were measured during the follow-up (28 days). The aqueous humor was analyzed, using (1)H-nuclear magnetic resonance spectroscopy and principal components analysis (PCA). Results: IOP elevation was observed in the TA group during the follow-up, compared to the controls (p<0.01). The IOP was decreased in the TA+GL group and the GL+TA group, compared to the TA group (p<0.05). Both in flash ERG and VEP, the amplitudes were decreased, and the implicit time was prolonged in the TA group, compared to the controls (p<0.05); and the parameters were improved after intervention of GL, compared to the TA group (p<0.05). PCA results indicated that TA could affect ocular metabolism (especially the sugar metabolism), and GL could inhibit it. Conclusions: The administration of GL could suppress OH induced by TA in rabbits, and improve their electrophysiological parameters. Metabolomics is a useful tool in ophthalmology research. Our results indicate that TA-induced ocular metabolism changes could be compensated by GL.Biochemistry & Molecular BiologyOphthalmologySCI(E)6ARTICLE2242056-20641

3D printing high interfacial bonding polyether ether ketone components via pyrolysis reactions

Recently, 3D-printed polyether-ether-ketone (PEEK) components have been shown to offer many applications in state-of-the-art electronics, 5G wireless communications, medical implantations, and aerospace components. Nevertheless, a critical barrier that limits the application of 3D printed PEEK components is their weak interfacial bonding strength. Herein, we propose a novel method to improve this unsatisfied situation via the interface plasticizing effect of benzene derivatives obtained from the thermal pyrolysis of trisilanolphenyl polyhedral oligomeric silsequioxane (POSS). Based on this method, the bonding strength of the filaments and interlayers of 3D-printed POSS/PEEK components can reach 82.9 MPa and 59.8 MPa, respectively. Moreover, the enhancing mechanism of the pyrolysis products derived from the POSS is characterized using pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), Fourier transform infrared spectroscopy (FTIR), and X-ray computed tomography (X-CT). Our proposed strategy broadens the novel design space for developing additional 3D-printed materials with satisfactory interfacial bonding strength

LGR6 Is a High Affinity Receptor of R-Spondins and Potentially Functions as a Tumor Suppressor

BACKGROUND: LGR6 (leucine-rich repeat containing, G protein-coupled receptor 6) is a member of the rhodopsin-like seven transmembrane domain receptor superfamily with the highest homology to LGR4 and LGR5. LGR6 was found as one of the novel genes mutated in colon cancer through total exon sequencing and its promoter region is hypermethylated in 20-50% of colon cancer cases. In the skin, LGR6 marks a population of stem cells that can give rise to all cell lineages. Recently, we and others demonstrated that LGR4 and LGR5 function as receptors of R-spondins to potentiate Wnt/β-catenin signaling. However, the binding affinity and functional response of LGR6 to R-spondins, and the activity of colon cancer mutants of LGR6 have not been determined. PRINCIPAL FINDINGS: We found that LGR6 also binds and responds to R-spondins 1-3 with high affinity to enhance Wnt/β-catenin signaling through increased LRP6 phosphorylation. Similar to LGR4 and LGR5, LGR6 is not coupled to heterotrimeric G proteins or to β-arrestin following R-spondin stimulation. Functional and expression analysis of three somatic mutations identified in colon cancer samples indicates that one mutant fails to bind and respond to R-spondin (loss-of-function), but the other two have no significant effect on receptor function. Overexpression of wild-type LGR6 in HeLa cells leads to increased cell migration following co-treatment with R-spondin1 and Wnt3a when compared to vector control cells or cells overexpressing the loss-of-function mutant. CONCLUSIONS: LGR6 is a high affinity receptor for R-spondins 1-3 and potentially functions as a tumor suppressor despite its positive effect on Wnt/β-catenin signaling

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Investigation of the Structure-Property Effect of Phosphorus-Containing Polysulfone on Decomposition and Flame Retardant Epoxy Resin Composites

The flame retardant modification of epoxy (EP) is of great signification for aerospace, automotive, marine, and energy industries. In this study, a series of EP composites containing different variations of phosphorus-containing polysulfone (with a phosphorus content of approximately 1.25 wt %) were obtained. The obtained EP/polysulfone composites had a high glass transition temperature (Tg) and high flame retardancy. The influence of phosphorus-containing compounds (ArPN2, ArPO2, ArOPN2 and ArOPO2) on the thermal properties and flame retardancy of EP/polysulfone composites was investigated by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), a UL-94 vertical burning test, and cone calorimeter tests. The phosphorus-containing polysulfone enhanced the thermal stability of EP. The more stable porous char layer, less flammable gases, and a lower apparent activation energy at a high degree of conversion demonstrated the high gas inhibition effect of phosphorus-containing compounds. Moreover, the gas inhibition effect of polysulfone with a P⁻C bond was more efficient than the polysulfone with a P⁻O⁻C bond. The potential for optimizing flame retardancy while maintaining a high Tg is highlighted in this study. The flame-retardant EP/polysulfone composites with high thermal stability broaden the application field of epoxy

Flexural Properties and Fracture Behavior of CF/PEEK in Orthogonal Building Orientation by FDM: Microstructure and Mechanism

Fused deposition modeling possesses great advantages in fabricating high performance composites with controllable structural designs. As such, it has attracted attention from medical, automatic, and aerospace fields. In this paper, the influence of short carbon fibers (SCFs) and the orthogonal building orientation on the flexural properties of printed polyether ether ketone (PEEK) composites are systematically studied. The results show that the addition of SCFs raises the uniform nucleation process of PEEK during 3D printing, decreases the layer-to-layer bonding strength, and greatly changes the fracture mode. The flexural strength of vertically printed PEEK and its CF-reinforced composites show strengths that are as high as molded composites. X-ray micro-computed tomography reveals the microstructure of the printed composites and the transformation of pores during bending tests, which provides evidence for the good mechanical properties of the vertically printed composites. The effect of multi-scale factors on the mechanical properties of the composites, such as crystallization in different positions, layer-by-layer bonding, and porosity, provide a successful interpretation of their fracture modes. This work provides a promising and cost-effective method to fabricate 3D printed composites with tailored, orientation-dependent properties

Distribution and Release of Volatile Organic Sulfur Compounds in Yangcheng Lake

Volatile organic sulfur compounds (VOSCs) function as a water–atmosphere link in the global sulfur cycle. It is generally believed that the vast majority of VOSCs are released from the ocean. However, due to the pervasive eutrophication and pollution of inland waters, the VOSC production and emission in rivers, lakes and reservoirs are attracting more attention. In this study, the temporal and spatial distributions of three VOSCs, including methanethiol, Dimethyl sulfide, and dimethyl disulfide in Yangcheng Lake, a eutrophic shallow lake, are investigated monthly and seasonally. Results show that VOSCs are higher in summer and autumn, with the western region as a hotspot. Our results show a positive correlation between VOSC and phytoplankton biomass (p < 0.05). Interestingly, from algal phylum composition, all the phylum, except those with low biomass, played a positive effect on VOSCs’ concentration. We did not find any specific phylum or species of cyanobacteria that contributed solely to the VOSCs. The water-air effluxes of Dimethyl sulfide (DMS) are estimated by a stagnant film model. The DMS effluxes from Yangcheng Lakes were higher than deep lakes and similar to the ocean, indicating that VOSCs, particularly DMS, in those eutrophic shallow lakes were non-negligible

Distribution and Release of Volatile Organic Sulfur Compounds in Yangcheng Lake

Volatile organic sulfur compounds (VOSCs) function as a water–atmosphere link in the global sulfur cycle. It is generally believed that the vast majority of VOSCs are released from the ocean. However, due to the pervasive eutrophication and pollution of inland waters, the VOSC production and emission in rivers, lakes and reservoirs are attracting more attention. In this study, the temporal and spatial distributions of three VOSCs, including methanethiol, Dimethyl sulfide, and dimethyl disulfide in Yangcheng Lake, a eutrophic shallow lake, are investigated monthly and seasonally. Results show that VOSCs are higher in summer and autumn, with the western region as a hotspot. Our results show a positive correlation between VOSC and phytoplankton biomass (p < 0.05). Interestingly, from algal phylum composition, all the phylum, except those with low biomass, played a positive effect on VOSCs’ concentration. We did not find any specific phylum or species of cyanobacteria that contributed solely to the VOSCs. The water-air effluxes of Dimethyl sulfide (DMS) are estimated by a stagnant film model. The DMS effluxes from Yangcheng Lakes were higher than deep lakes and similar to the ocean, indicating that VOSCs, particularly DMS, in those eutrophic shallow lakes were non-negligible