Objective: Immunotoxin rRTA:DS27, which was prepared by conjugating DS27 with recombinanl ricin a chain, was compared with ricin:DS27 as immunotoxins. Methods: System analysis were performed regard to their cell-specific cytotoxicity, inhibition on the proliferation of hemoapeutic potential cells, immunogold-labelled intracellular routing and effect of NH_(4)Cl on the cytotoxicity. Results: Results showed that rRTA: DS27 got a more specific cytotoxicity and a weaker inhibition on the proliferation of hemoapeutic potential cells than ricin:DS27, NH_(4)Cl could obsolutelyy enhence the cytotoxicity of rRTA:DS27. Conclusion: rRTA:DS27 had more advantages than ricin: DS27 as immunotoxins.

To obtain active hFKBP52 protein for screening novel neu rotrophic drugs. Semi-nested and overlap PCR and affinity chromatography were u sed. hFKBP52 gene was cloned successfully from human fetal brain cDNA library, a nd then highly expressed (about 30%) as fusion protein in pET28a(+) vector syste m. The recombinant protein was purified as one band on SDS-PAGE. The purified h FKBP52 showed peptidyl-prolyl cis-trans isomerase (PPIase) activity, simil ar to the wild type.

Objective:To assess the value of the ROX index in evaluating the efficacy of high-flow nasal cannula oxygen therapy (HFNC) in patients with coronavirus infected disease (COVID-19).Methods:This is a retrospective study. The included patients were diagnosed as COVID-19 in the intensive care unit (ICU) of the Cancer Center of Union Hospital affiliated to Tongji Medical College of Huazhong University of Science and Technology from February 15, 2020 to March 15, 2020. All the patients were treated by HFNC. According to whether the patient subsequently received non-invasive positive pressure ventilation or invasive positive pressure ventilation, patients were divided into the HFNC success group and the HFNC failure group. Parameters in the two groups such as basic characteristics, lactic acid, number of chest radiographs, APACHE II, lymphocyte count, baseline respiratory rate, baseline percutaneous oxygen saturation, baseline PaO 2/FiO 2, baseline ROX index, and ROX index after 2, 6 and 12 h HFNC treatment were analyzed with t test, Chi-square test or rank sum test. Results:A total of 57 cases were included in this study. There were no significant differences in sex, age, comorbidities, lactic acid, quadrants of chest radiograph lung infection, APACHE II, lymphocyte count, and baseline respiratory frequency, transcutaneous oxygen saturation, oxygenation index, and ROX index between the HFNC success group and the HFNC faliure group ( P>0.05). Logistic regression analysis showed that ROX index after 2 h HFNC treatment ( OR=0.069), ROX index after 6 h HFNC treatment ( OR=0.194) and ROX index after 12 h HFNC treatment ( OR=0.036) were all protective factors for the therapeutic effect of HFNC treatment in COVID-19 patients. ROC curve showed that there were significant differences in ROX index after 2 h HFNC treatment, ROX index after 6 h HFNC treatment, and ROX index after 12 h HFNC treatment ( P<0.05). In the evaluation index, the area under the ROC curve of the ROX index after 2 h HFNC treatment was 0.838, the sensitivity was 64.5%, and the specificity was 100%. After 6 h HFNC treatment, the area under the ROX index ROC curve was 0.762, the sensitivity was 64.5%, and the specificity was 92.3%. After 12 h HFNC treatment, the ROX index ROC curve area was 0.866, the sensitivity was 67.7%, and the specificity was 100%. Conclusions:The ROX index can be used to evaluate the efficacy of HFNC in COVID-19 patients in a timely, simple and real-time manner.

The key to killing target cells by immunotoxin depends on the specific recognition of antibody to target cell and the cytotoxic effect of toxin. The comparative study of the killing effects of two anti-T immunotoxins, CD5:Ricin and CD5:rRA, on target cells was performed. The elimination rate of immunotoxins was analysed by flow cytometry and MLR. The effect of immunotoxins on the proliferation of hematopoiesis was evaluted by CFU-GM. The results showed that (1) CD5(+) T cells were eliminated and CD25(+) CD3(+) activated T cells were concentration-dependently inhibited by the two immunotoxins in the range of 10(-9) - 10(-11) mol/L; (2) both immunotoxins significantly inhibited the mixed lymphocyte reaction, and the inhibiting effect of CD5:rRA to T cell proliferation was markedly lower than that of CD5:Ricin in the range of 10(-10) - 10(-11) mol/L; (3) the combination of CD5:rRA with 10 mmol/L NH(4)Cl increased the T cell elimination rate; and (4) the two immunotoxins and the combination of NH(4)Cl and CD5:rRA did not suppressed proliferation of granulocyte-macrophage progenitors in the range of concentrations with killing effect. It was concluded that T cell and activated T cell could be eliminated effectively by immunotoxins, the proliferation of granulocyte-macrophage progenitor was not inhibited significantly.