Preparation of a Cellulosic Photosensitive Hydrogel for Tubular Tissue Engineering

Since the concept of tissue engineering was proposed, biocompatible hydrogel materials have attracted the attention of researchers. With the help of three-dimensional (3D) printing technology, precise shaping of hydrogels can be realized. In this paper, we synthesized a cellulosic photosensitive acrylamide (AM)/N,N-methylenebisacrylamide (MBA) hydrogel. With the high-efficiency water-soluble photoinitiator TPO@Tw developed by our research group, the efficient photocuring cross-linking process of the hydrogel can be realized under 405 nm visible light. In consideration of the viscosity, curing mass, curing depth, and break distance of the hydrogel, we screened out hydroxypropyl cellulose (HPC) as the preferred tackifier of the material. The addition of HPC greatly improved the mechanical properties of the hydrogel. The compressive modulus of the optimal sample AM-HPC-5 increased by 709.2% and the tensile strength increased by 76.7% compared with the blank control group. By adding a PEGDA shell to the surface of the material, the water retention capacity of the hydrogel was effectively improved. The water loss rate was greatly reduced. The 3D wooden-pile structure model was printed by a DIW 3D printer. Further, through coaxial extrusion, the microtubule structure that may be applied in tissue engineering was obtained. Cell experiment results showed high biocompatibility of the hydrogel. NIH 3T3 cells could adhere and grow on the surface of microtubules

Production of Clean Fuels by Catalytic Hydrotreating a Low Temperature Coal Tar Distillate in a Pilot-Scale Reactor

China is one of the largest coal producers in the world and abundant coal tar is produced from coal gasification and carbonization every year. Thus, catalytic hydrotreating coal tar for the production of clean fuel has received substantial attention. In this work, clean liquid fuel was obtained from the catalytic hydrogenation of a low temperature coal tar (LTCT) distillate in a four-stage fixed bed reactor with various catalyst combinations on the pilot scale. Effects of dominant hydrotreating parameters, reaction temperature (290–390 °C), H₂ pressure (8–15 MPa), and liquid hourly space velocity (0.2–0.6 h^–1), on hydrotreating activity, the intermediate and final products, and chemical components of the hydrogenated oils were evaluated. Meanwhile, a possible reaction scheme for the conversion of alkyl-naphthalenes (AN) and phenols in feedstock was probed. The results showed that the four-stage reacting system was capable of removing sulfur and nitrogen to less than 10 μg/g. Furthermore, after hydrotreating, AN were transformed into decalins, tetralin, and indenes, and alkyl-cycloalkanes (CA) were the main and final products of phenolic compound hydrodeoxygenation (HDO). In addition, coke formation of the spent catalysts was also studied by thermogravimetric techniques, which suggested that the coke deposits are mainly concentrated in the second and third stages of the reactor. The results of this work show that high-quality clean fuels can be obtained through the multistage hydrotreating process with a catalyst gradation technology, which may bridge the gap between fundamental research and industrial production and offer a route for deep processing of LTCT

Discovery of Novel 1,2,4-Thiadiazole Derivatives as Potent, Orally Active Agonists of Sphingosine 1-Phosphate Receptor Subtype 1 (S1P₁)

A novel series of 1,2,4-thiadiazole compounds was discovered as selective S1P₁ agonists. The extensive structure–activity relationship studies for these analogues were reported. Among them, <b>17g</b> was identified to show high in vitro potency with reasonable free unbound fraction in plasma (<i>F</i>_u > 0.5%), good brain penetration (BBR > 0.5), and desirable pharmacokinetic properties in mouse and rat. Oral administration of 1 mg/kg <b>17g</b> resulted in significant peripheral lymphocytes reduction at 4 h after dose and rapid lymphocytes recovery at 24 h. <b>17g</b> showed a transient lymphopenia profile in the repeated dose study in mouse. In addition, <b>17g</b> also demonstrated efficacy comparable to that of FTY720 (<b>1</b>) in the mouse EAE model of MS

Discovery of Biaryl Amides as Potent, Orally Bioavailable, and CNS Penetrant RORγt Inhibitors

A novel series of biaryl amides was identified as RORγt inhibitors through core replacement of a starting hit <b>1</b>. Structure–activity relationship exploration on the biaryl moiety led to discovery of potent RORγt inhibitors with good oral bioavailability and CNS penetration. Compounds <b>9a</b> and <b>9g</b> demonstrated excellent <i>in vivo</i> efficacy in EAE mice dose dependently with once daily oral administration