OBJECTIVETo develop an assay methodology for determination of lumbrukinase potency in Rongshuan capsules.

METHODThe agarose-fibrin plate assay methodology for determination of Lumbrukinase potency in Rongshuan capsules was studied including durability, specificity, linearity range, product's handling method, accuracy , repetitiveness, solution stability, recovery and statistical method. The method of parallel line assay based on quantitative responses in statistical methods for biological assays was used in the statistics of potency assay.

RESULTThe durability and specificity of assay accord with the requirement; The linearity range was 12.5 to approximately 400 U, the RSD of accuracy tests was 3.2%, the RSD of repetitiveness tests was 8.3%, the solution is stable under 4 degrees C for 72 hours, the recovery rate was 97.0% and the RSD of recovery assays was 16.5%.

CONCLUSIONThe agar-fibrin plate assay is rapidly, feasible, simple, convenient and accurate way for determining the Lumbrukinase potency. The method of parallel line assay based on quantitative responses in statistical methods for biological assays can control the error of determination.

Animals ; Biological Assay ; methods ; Capsules ; analysis ; Endopeptidases ; analysis ; Pharmaceutical Preparations ; analysis

Ischemia-reperfusion injury after lung transplantation is the main cause of primary graft dysfunction, which will subsequently reduce the function of lung allograft and lower the overall survival rate of lung transplant recipients. As a physiological regulatory molecule, hydrogen molecule has the functions of anti-inflammation, easing oxidative stress, alleviating direct cell injury and mitigating epithelial edema. Recent studies have demonstrated that hydrogen molecule and its products (hydrogen and hydrogen-rich solution) could significantly mitigate ischemia-reperfusion injury and postoperative complications after lung transplantation. In this article, the protective effect and exact mechanism of hydrogen molecule and its products in lung transplantation were reviewed, aiming to provide theoretical basis for the application of hydrogen molecule and its products as a novel treatment for lung transplantation-related complications, enhance the overall prognosis and improve the quality of life of lung transplant recipients

Objective To modify the mouse model of orthotopic left lung transplantation from different perspectives, aiming to establish a simpler, faster and stabler mouse model of lung transplantation. Methods Based on preliminary modified rat model of orthotopic left lung transplantation established by our team, varying extent of modifications were made regarding the tracheal intubation, cannula preparation and anastomosis procedures of orthotopic left lung transplantation in the recipient mice. Orthotopic left lung transplantation in 40 mice were performed by an operator with microsurgical experience. The dissection of the recipient's hilar structure was carried out at the plane of the hilar clamp model within the reverse-view, and the three branches (left main bronchus, pulmonary artery and pulmonary vein) of the pulmonary hilum were anastomosed in turn by the "pendulum" anastomosis method. The operation time of each procedure was recorded. The recipient mice were sacrificed at postoperative 2 weeks, and the incidence of postoperative complications was recorded. Results Lung transplantation was successfully completed in 40 mice, with no bronchial and vascular tearing or twisting, and no bleeding at the anastomosis site. The overall cardiopulmonary procurement time was (10.7±1.5) min, cannula preparation time was (16.2±1.5) min, cold ischemia time was (25.1±2.4) min, warm ischemia time was (19.4±1.6) min, and the total operation time was (57.2±2.9) min, respectively. During the follow-up from 6 to 14 days after surgery, one recipient mouse died of pleural effusion, probably caused by infection. No pneumothorax, thrombosis or atelectasis was found in the remaining recipient mice during postoperative follow-up. Conclusions The modified mouse model of orthotopic left lung transplantation based on "pendulum" anastomosis of the reverse-view plane possesses multiple advantages of short operation time, high success rate and few complications, which is expected to become an alternative model of studying pathological changes after lung transplantation and worthy of further application.