Objective To establish the model of serum-caused damage to pulmonary microvascular endothelial cells (PMVECs) of mice with renal ischemia-reperfusion (I/R) injury.Methods Mice PMVECs were cultured to measure the standard trans-endothelial electrical resistance (TER) in the monolayer of PMVECs.When PMVECs were cultured and arranged in compact monolayer and TER was achieved,they were divided into 4 groups (n =3 each) using a random number table:serum of normal mice group (NS group) and different concentrations (5％,10％ and 20％) of serum of mice with renal I/R injury groups (IRS5 group,IRS10group and IRS20 group).The PMVECs were cultured for 1 h in the serum-free endothelial culture medium.The 0.8 and 0.2 ml culture medium containing 20％ serum of normal mice were then added to the upper and lower chambers,respectively,in group NS.The 0.8 and 0.2 ml culture medium containing 5％,10％ and 20％ serum of mice with renal I/R injury were then added to the upper and lower chambers in IRS5,IRS10 and IRS20 groups,respectively.100 μg/ml FITC-BSA 100 μl was added to the upper chamber in the four groups.At 3,6,9,12,15,18,21 and 24 h of incubation,the PMVEC monolayer permeability (apparent permeability coefficient,Pa) was detected.Results Compared with NS group,the Pa was significantly increased at 12 and 15 h of incubation in IRS5 group,and the Pa was increased at 6-24 h of incubation in IRS10 and IRS20 groups.Compared with IRS5 group,the Pa at 21 and 24 h in IRS10 group and at 9-24 h in IRS20 group were significantly increased.Conclusion Both 10％ and 20％ serum of mice with renal I/R injury can successfully establish the model of damage to PMVECs,and 20％ serum causes a more severe damage.

Objective To evaluate the effect of the serum of rats with hepato-pulmonary syndrome (HPS) on the expression of caveolin-1 and VE-cadherin in pulmonary microvascular endothelial cells (PMVECs).Methods Among the 40 healthy Sprague-Dawley rats,aged 3-4 months,weighing 220-250 g,20 rats were taken randomly for establishment the model of HPS which was produced by chronic ligation of the common bile duct,and the left 20 rats served as sham operation group.Primary PMVECs were harvested from healthy adult Sprague-Dawley rats and inoculated in ECM culture medium or on 96-well culture plate.The PMVECs of 4th-9th generation were randomly divided into 2 groups (n =36 each):control group (group C) and HPS group.In group C,the serum obtained from normal rats in sham operation group was added to PMVECs,while the serum obtained from rats with HPS was added in HPS group.The final concentration of serum was 10％.After being incubated for 12,24 and 36 h (T1-3),the expression of caveolin-1 and VE-cadherin in PMVECs was detected by Western blot,and the PMVEC adhesion rate and proliferation were determined by CKK-8 method.Results Compared with group C,the expression of caveolin-1 and VE-cadherin was significantly down-regulated,the cell adhesion rate was decreased,and the proliferation of PMVECs was enhanced in HPS group.Conclusion The serum of rats with HPS induces weakened PMVEC contact inhibition through down-regulating caveolin-1 and VE-cadherin expression.

Objective To evaluate the role of Src kinase in liver injury in endotoxemic mice.Methods Forty-eight female BABL/c mice,aged 3-4 months,weighing 15-20 g,were randomly divided into 3 groups (n =16 each) using a random number table:control group (C group),endotoxemia group (lipopolysaccharide (LPS) group) and Src kinase inhibitor PP2 group (PP2 group).Endotoxemia was induced by intraperitoneal LPS 20 mg/kg in LPS and PP2 groups,while the equal volume of PBS was given in group C.In PP2 group,PP2 1 mg/kg was injected intraperitoneally at 2 h after LPS administration.At 6 h after LPS or PBS injection,8 mice in each group were chosen,and blood samples were collected from the abdominal aorta for determination of the serum levels of alkaline phosphatase (ALP).The mice were then sacrificed and livers were removed for determination of nuclear factor E2-related factor 2 (Nrf2) level,superoxide dismutase (SOD) activity,malondialdehyde (MDA) content and myeloperoxidase (MPO) activity in liver tissues.The other 8 mice in each group were sacrificed at 24 h after LPS or PBS injection,and the livers were harvested for examination of pathological changes.Results Compared with C group,the serum levels of ALP and MDA content and MPO activity in liver tissues were significantly increased,and SOD activity and Nrf2 levels in liver tissues were decreased in LPS and PP2 groups.Compared with LPS group,the serum levels of ALP and MDA content and MPO activity in liver tissues were significantly decreased,and SOD activity and Nrf2 levels in liver tissues were increased in PP2 group.The pathological changes of liver tissues were significantly attenuated in PP2 group as compared with LPS group.Conclusion Src kinase is involved in endotoxemia-induced liver injury in mice.

Objective:To construct a recombinant plasmid pET30a-leucine-rich repeat (LRR) containing 15 (LRRC15) of Taenia solium, prokaryotically express and purify the LRRC15 recombinant protein, and prepare a rabbit polyclonal antibody. Methods:The LRRC15 protein encoding gene of Taenia solium was obtained by whole gene synthesis; it was cloned into pET30a vector, and the recombinant plasmid pET30a-LRRC15 was constructed and identified by double-enzyme PCR; the recombinant plasmid was transformed into competent cells of Escherichia coli BL21 (DE3), and the recombinant protein LRRC15 was induced to express by isopropyl-beta-D-thiogalactopyranoside (IPTG), the expression product was analyzed and identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE); the LRRC15 recombinant protein was purified by Ni-IDA affinity columns, the purified recombinant protein was analyzed and identified by SDS-PAGE, and the specificity of the purified recombinant protein was identified by Western blot (WB); the New Zealand rabbits were immunized with purified LRRC15 recombinant protein to prepare polyclonal antibodies against LRRC15, and the potency of the purified polyclonal antibody was determined by indirect enzyme-linked immunosorbent assay (ELISA). Results:After PCR identification, a band with a length of 1 506 bp was amplified, which was consistent with the LRRC15 gene; after SDS-PAGE and WB identification, the LRRC15 target protein with a relative molecular mass ( Mr) of about 55.36 × 10 3 was obtained; after immunizing New Zealand rabbits with purified LRRC15 recombinant protein, a polyclonal antibody against LRRC15 was obtained, and its potency was 1∶1 587 200. Conclusion:The recombinant plasmid pET30a-LRRC15 is successfully constructed, the LRRC15 recombinant protein of Taenia solium is prepared, and a high purity and high potency rabbit anti polyclonal antibody against LRRC15 recombinant protein is obtained.

Objective:Lung ultrasound (LUS) has been used in the diagnosis of neonatal respiratory distress syndrome(RDS) successfully, but there have been no multicenter prospective studies to verify its reliability or determine how to grade RDS with LUS findings.This study aimed to discuss the necessity and feasibility of using LUS findings to determine RDS grades through a multicenter prospective study.Methods:Every researcher participated in the National Neonatal Lung Ultrasound Training Course and receiving 3-6 months of lung ultrasound system training at the National Neonatal Lung Ultrasound Training Center.Patients between June 2018 and May 2020 who met the RDS ultrasound diagnostic criteria and had full available clinical data were included in this study.The LUS examination was completed immediately after the patients were admitted to the hospital.Some of them also underwent chest X-ray examination.Arterial blood gas analysis was completed immediately before or after the LUS ultrasound examination.RDS grading was performed according to the LUS findings and whether the patient had serious complications.Results:A total of 275 qualifying cases were included in this study, which included 220 premature infants and 55 full-term infants, and the primary RDS occurred in 117 cases (42.5%), and secondary RDS occurred in 158 cases (57.5%). LUS manifestations of RDS patients can be divided into three categories: (1)A ground-glass opacity sign: which could be found among 50 infants when they were admitted to the hospital (that was, at their first LUS examination). Twenty-eight of these infants were considered to have wet lungs and were not sent for special management on admission, but LUS showed typical snowflake-like lung consolidation within 0.5 to 4 hours.Twenty-two of them were given mechanical ventilation with exogenous pulmonary surfactant; Eighteen cases were controlled within 6-12 hours, but the lung lesions became more severe in the other 4 infants (due to severe intrauterine infection). (2)Snowflake-like lung consolidations: the first LUS on admission showed typical snowflake-like lung consolidation involving areas ranging from 1-2 intercostal spaces to 12 lung divisions in 204 cases.Thirty-eight infants among them the lung consolidation only had involvement of 1-2 intercostal spaces at the time of admission; Fifteen of them received invasive respiratory support and recovered within 4-12 hours.Twelve patients received noninvasive respiratory support; Seven of them recovered, while five cases developed severe lung illness.The remaining 11 patients who were not given any form of ventilator support developed severe conditions within 1-4 hours.Thirty of them showed snowflake signs involving 12 lung regions at admission.The remaining 136 patients had lung consolidation degree between the two degree above condition.(3)Snowflake-like sign with complications: Twenty-one patients had severe complications such as pneumothorax, pulmonary hemorrhage or/and persistent pulmonary hypertension of the newborn or large area atelectasis, etc, although snowflake lung consolidation did not involve all lung regions.Conclusion:(1) LUS is reliable and accurate for diagnosing RDS.RDS has the same characteristics on ultrasound for both preterm and full-term infants, both primary and secondary RDS.(2) To facilitate the management of RDS, it is necessary to classify RDS according to the ultrasound findings and the presence of severe complications.(3) Based on the results of this study, it is recommended that RDS can be divided into mild, moderate and severe degrees.The exact standards for grading are as follows: Mild RDS: the early stage of RDS, in which lung consolidation shows as a ground-glass opacity sign on ultrasound; Moderate RDS: lung consolidation shows a snowflake sign on ultrasound, not all of the lung fields are involved; Severe RDS meets one or more of the following criteria: lung consolidation shows as a snowflake sign on ultrasound and all lung regions are involved, or regardless of its degree and extent, lung consolidation has caused serious complications, such as pulmonary hemorrhage, pneumothorax, persistent pulmonary hypertension of the newborn, or/and a large area of pulmonary atelectasis.