罗勒多糖对博莱霉素诱导小鼠肺纤维化的作用

目的：研究罗勒多糖对博莱霉素诱导肺纤维化小鼠肺组织病理的影响。方法：将40只C57BL/6J雄性小鼠随机分为假手术组，模型组，罗勒多糖高、中、低剂量组。模型组和罗勒多糖组小鼠，气管注射博来霉素（1.5mg/kg），诱导其肺纤维化，假手术组注射等量生理盐水同法造模。罗勒多糖组小鼠每天用100、50、25mg/kg罗勒多糖，假手术组、模型组小鼠同法给药相应剂量的生理盐水，每天给药。造模28d后处死小鼠，肺组织病理切片进行HE和Masson染色，观察肺泡炎和肺纤维化程度，ELISA检测肺组织羟脯氨酸含量。结果：与模型组相比，罗勒多糖不同剂量组小鼠肺组织胶原染色明显减少，肺泡间隔增厚程度较轻，区域性实质性病变少见，炎症细胞浸润减少，纤维化程度均有所减轻，羟脯氨酸含量下降，中、高剂量组优于低剂量组。结论：罗勒多糖能减轻博莱霉素诱导肺纤维化小鼠肺组织炎症和肺纤维化程度，是一种潜在的可用于特发性肺纤维化（IPF）治疗的中药提取物。

Screening and Identification of Cellulase-producing Strains Isolated from Crayfish Intestine

The intestinal microbes are the main driving force for crayfish to degrade cellulose and hemicellulose. In order to explore the probiotic resources and genetic resources of degrading cellulose in the crayfish intestine,the cellulase-producing bacteria were isolated from crayfish intestine by plate screening method,and the genome of the maximum active strain was analyzed by Illumina MiSeq high-throughput sequencing. Morphological and 16S rRNA gene molecular identification showed that strain 13 was Bacillus velezensis,and strain 33 was Bacillus subtilis. Strain 33 has multiple hydrolase activities and high cellulose-degrading ability. The high-throughput sequencing results indicated that the bacterial genome contained many carbohydrate-related enzyme genes. Crayfish intestines are rich in cellulose-degrading bacteria,and Bacillus bacteria accounts for a certain proportion.