A successfully treated case of colchicine poisoning with lethal dose / 中华危重病急救医学

At present, there is no specific antidote for colchicine intoxication, and 0.8 mg/kg is its lethal dose.The prognosis of colchicine intoxication patients is closely related to the dosage, but the individual difference is very great. A 38-year-old man with colchicine poisoning was admitted to the Seventh People's Hospital of Shanghai University of Traditional Chinese Medicine, who had ingested 80 mg colchicine tablets (1.19 mg/kg) orally for 4 hours. He was immediately put on gastric lavage, enema, and catharsis. Continuous blood purification was performed for 34 hours and 22 minutes, with a combination of hemoperfusion (HP) and continuous veno-venous hemofiltration dialysis (CVVHDF). He also received a large dose of the glucocorticoid with 80 mg of methylprednisolone injected intravenously every 8 hours and organ function support. The patient was hospitalized for 2 weeks and discharged with improvement. The successful treatment of this case was reported for reference.

Identification and characterization of six glycosyltransferases involved in the biosynthesis of a new bacterial exopolysaccharide in Paenibacillus elgii.

Paenibacillus elgii B69 produces a new xylose-containing exopolysaccharide (EPS) that effectively removes the pollutants from wastewater through flocculation. However, information about the biosynthesis of this EPS is limited. In this study, sequence analysis showed six putative glycosyltransferases (GTs) genes in polysaccharide gene clusters involved in glycosidic linkages of repeating units. Each gene was deleted and phenotypes were examined to understand the functions of these genes. Two of the genes were deleted successfully to encode a priming glucose GT and a side-chain xylose GT, but other genes were unsuccessfully deleted because of the accumulation of toxic intermediate products. The six genes were cloned and expressed in Escherichia coli, and the corresponding enzymes were purified. The activity of GTs was analyzed through mass spectrometry by using the purified membrane fraction as a lipid carrier receptor after a hexasaccharide repeated unit was reconstructed in vitro. The specificities of six different GTs and the building order of the hexasaccharide were characterized. This study provided a basis for future research on the biosynthetic pathway of EPS in Paenibacillus or other genera.

Progress in antimicrobial substances of endophytes / 生物工程学报

Isolation and characterization of metabolites produced by endophytes are significant ways to search for novel natural active substances, proving that the endophytes are the unique resources of newer and more effective compounds. Many new compounds with antimicrobial activity from different endophytes have been isolated so far. These new compounds provide alternatives to fight against multi-drug resistance of microorganisms. This review outlined the major achievements and latest developments of endophytes, including the diversity of endophytes and antimicrobial activity of endophytes, as well as its development in China.

Bone marrow mesenchymal stem cells combined with theaflavin for steroid-induced avascular necrosis of femoral head / 中国组织工程研究

BACKGROUND:Pathological mechanism of femoral head necrosis is not fuly known, and high-dose corticosteroids are prone to induce femoral head necrosis. OBJECTIVE:To investigate the clinical effect of bone marrow mesenchymal stem cels combined with theaflavin on steroid-induced avascular necrosis of femoral head in rats. METHODS: Rat bone marrow mesenchymal stem cels were isolated and culturedin vitro and compounded onto gelatin sponge, and then, divided into four groups: model group, decompression group, cel transplantation group and combined group. Models of steroid-induced avascular necrosis of femoral head were established using liquid nitrogen method. In the combined group, gelatin sponge carrying bone marrow mesenchymal stem cels was transplanted and 250 mg theaflavin was given daily after modeling. RESULTS AND CONCLUSION:At 4 weeks after modeling, the femoral head samples in the four groups were round with exfoliation of articular cartilage that was pale in color. Then, the exfoliation of articular cartilage was aggravated in the model group, and some specimens appeared to colapse; the femoral head specimens in the combined group were round and pale. Until the 8th week after modeling, bone necrosis was increased in the model group; osteoblasts were found in the decompression group with fibrous calus formation; a few of empty bone lacunae appeared with irregular medulary cavity in the cel transplantation group; a large amount of new bone tissues formed in the combined group, and intramedulary adiocytes were in regular array. At 4 and 8 weeks after modeling, the number of empty bone lacunae was significantly lower in the combined group than the other groups (P < 0.05). These findings indicate that bone marrow mesenchymal stem cels combined with theaflavin is an ideal therapy for steroid-induced avascular necrosis of femoral head.