Changes in intestinal microflora in rats with acute respiratory distress syndrome

AIM:To implement high-throughput 16S rDNA sequencing to study microbial diversity in the fecal matter of rats with acute lung injury/acute respiratory distress syndrome(ALI/ARDS).METHODS:Intratracheal instillation of lipopolysaccharide was used to induce ALI,and the pathological changes in the lungs and intestines were observed.D-lactate levels and diamine oxidase(DAO)activities were determined by enzymatic spectrophotometry.The fragments encompassing V4 16S rDNA hypervariable regions were PCR amplified from fecal samples,and the PCR products of V4 were sequenced by Illumina MiSeq.RESULTS:Increased D-lactate levels and DAO activities were observed in the model group(P<0.01).Sequencing results revealed the presence of 3780 and4142 species in the control and model groups,respectively.The percentage of shared species was 18.8419%.Compared with the control group,the model group had a higher diversity index and a lower number of species of Fusobacteria(at the phylum level),Helicobacter and Roseburia(at the genus level)(P<0.01).Differences in species diversity,structure,distribution and composition were found between the control group and early ARDS group.CONCLUSION:The detection of specific bacteria allows early detection and diagnosis of ALI/ARDS.

The efficacy of TKIs in treatment of human primary small cell lung cancer xenograft model in vivo

Objective: To study the treatmaient of non-small cell lung cancer, we established the HU-Prim allograft transplantation tumor model. Methods: The fresh tumor samples were transplanted in the right scapular subcutaneous layer of the severe combined immunodeficient Non-obese diabetic/severe combined immunodeficient(NOD/SCID) mice. The pathological features of the tumors were observed. Nonnecrotic tissue was inoculated subcutaneously into the right axillary. When the tumor in burdened rat grew approximately 100 mm3, according to the tumor size all the animals were divided into the following four groups, eight rats in each group: solvent control group, gefitinib group(100 mg/kg), erlotinib group(50 mg/kg), afatinib group(20 mg/kg). Aniamals were treated with drugs by intragastric(i.g.) administrated, once daily, for consecutively 14 days. Measure the tumor size 2-3 times every week. Results: Hu Prime1-NSCLC mutant sensitive xenograft model research data showed that reversible tyrosine kinase inhibitors gefitinib, erlotinib and irreversible tyrosine kinase inhibitor afatinib could effectively inhibit tumor growth in EGFR positive NSCLC allografts model. The pharmacodynamic activity of irreversible inhibitor was better than that of the reversible inhibitor. Specimens from clinical anthropogenic tumor retain characteristics of the human primary malignancy, histopathology, biological characteristics, and tumor markers, etc., which can more accurately reflect the characteristics of the tumor and the impact of interventions. Conclusion: The model is not only a good antitumor drug experimental platform, but also a new evaluation tool of individualized medication.