[Ultrasonographic manifestation and genetic analysis of a fetus with Stickler syndrome].

OBJECTIVE: To carry out genetic analysis for a family with a fetus manifesting micrognathia and a previous history for fetal micromandibular deformity. METHODS: Systematic ultrasound examination was carried out for the fetus, and the prenatal and postnatal phenotype of the first fetus were retrospectively analyzed. The fetus and his parents were subjected to whole exome sequencing (WES) to identify potential pathogenic variants. Candidate variants were verified by Sanger sequencing. RESULTS: Fetal ultrasound has indicated micrognathia. The first fetus was found to have micrognathia by prenatal ultrasonography and have featured macrosomia and dyspnea due to with tongue retraction, high palatal arch and small mandibular deformity. WES revealed that the fetus has a harbored a c.3G>C (p.Met1?) variant of the COL2A1 gene, which was inherited from the father who had myopia and retinal detachment. CONCLUSION: Stickler syndrome is mainly characterized prenatally by micrognathia, in addition with a variety of postnatal anomalies. The c.3G>C (p.Met1?) variant probably underlay the Stickler syndrome in this pedigree.

Efficient depolymerization of Kraft lignin to liquid fuels over an amorphous titanium-zirconium mixed oxide supported partially reduced nickel-cobalt catalyst.

A series of non-precious metal/metal oxide nickel-cobalt catalysts was prepared for a highly efficient depolymerization of Kraft lignin (KL) into liquid fuels using amorphous TiZr-oxide (Ti1-yZryO2) as a carrier. The effects of Ni-NiOx, Co-CoOx, NiCo-NiCoOx, NiCoOx and NiCo catalysts supported on amorphous TiZr-oxide carrier on KL depolymerization were investigated. It was found that the NiCo-NiCoOx/Ti1-yZryO2 catalyst is optimal for converting KL to petroleum ether (PE)-soluble product (mainly composed of monomers and dimers) in an 80.2% high yield at 320 °C for 24 h, with excellent reusability and a low formation of char. Under these conditions, the higher heating value (HHV) increased from 25.11 to 33.89 MJ/kg. A meticulous study on NiCo-NiCoOx/Ti1-yZryO2 catalysts revealed that the synergistic effect among Lewis acid sites, basic sites and metal active sites played an important role in obtaining high yields of monomers and low rates of char formation during lignin conversion.

Production of liquefied fuel from depolymerization of kraft lignin over a novel modified nickel/H-beta catalyst.

In this study, a novel modified nickel/H-beta (Ni/DeAl-beta) catalyst, which has active acidic sites and hydrogen binding sites, was prepared and used to produce liquefied fuel from lignin. The bifunctional Ni/DeAl-beta catalyst efficiently converted kraft lignin into liquefied fuel due to the synergistic effect of aluminum Lewis acid sites and nickel hydrogen binding sites. At a nickel content of 0.6 mmol/gzeolite, the Ni/DeAl-beta catalyst gave a high liquid product yield of 88.6% at 300 °C for 36 h. Most of the liquid product was dissolved in petroleum ether (73% of 88.6%), which was mainly composed of monomeric and dimeric degradation products. Under these conditions, the higher heating values (HHV) increased from 24.9 MJ/kg for kraft lignin to 32.0 MJ/kg for the liquid product. These results demonstrated the bifunctional Ni/DeAl-beta catalyst could be an efficient catalyst for lignin to liquefied fuel conversion.