Development and validation of a prognostic model for patients with sepsis in intensive care unit / 中华危重病急救医学

Objective:To analyze the risk factors related to the prognosis of patients with sepsis in intensive care unit (ICU), construct a nomogram model, and verify its predictive efficacy.Methods:A retrospective cohort study was conducted using data from Medical Information Mart for Intensive Care-Ⅳ 0.4 [MIMIC-Ⅳ (version 2.0)]. The information of 6 500 patients with sepsis who meet the diagnostic criteria of Sepsis-3 were collected, including demography characteristics, complications, laboratory indicators within 24 hours after ICU admission, and final outcome. Using a simple random sampling method, the patients were divided into a training set and a validation set at a ratio of 7∶3. The restricted cubic spline (RCS) was used to explore whether there was a linear relationship between each variable and the prognosis, and the nonlinear variables were truncated into categorical variables. All variables were screened by LASSO regression and included in multivariate Cox regression analysis to analyze the death risk factors in ICU patients with sepsis, and construct a nomograph. The consistency index, calibration curve and receiver operator characteristic curve (ROC curve) were used to evaluate the prediction efficiency of nomogram model. The decision curve analysis (DCA) was used to validate the clinical value of the model and its impact on actual decision-making.Results:Among 6 500 patients with sepsis, 4 551 were in the training set and 1 949 were in the validation set. The 28-day, 90-day and 1-year mortality in the training set were 27.73% (1?262/4?551), 34.76% (1?582/4?551), and 42.98% (1?956/4?551), respectively, those in the validation set were 27.24% (531/1?949), 33.91% (661/1?949), and 42.23% (823/1?949), respectively. Both in training set and the validation set, compared with the final survival patients, the death patients were older, and had higher sequential organ failure assessment (SOFA) score and simplified acute physiology scoreⅡ (SAPSⅡ), more comorbidities, less urine output, and more use of vasoactive drugs, kidney replacement therapy, and mechanical ventilation. By RCS analysis, the variables with potential nonlinear correlation with the prognosis risk of septic patients were transformed into categorical variable. The variables screened by LASSO regression were enrolled in the multivariate Cox regression model. The results showed that age [hazard ratio ( HR) = 1.021, 95% confidence interval (95% CI) was 1.018-1.024], SOFA score ( HR = 1.020, 95% CI was 1.000-1.040), SAPSⅡ score > 44 ( HR = 1.480, 95% CI was 1.340-1.634), mean arterial pressure (MAP) ≤ 75 mmHg (1 mmHg ≈ 0.133 kPa; HR = 1.120, 95% CI was 1.026-1.222), respiratory rate (RR; HR = 1.044, 95% CI was 1.034-1.055), cerebrovascular disease ( HR = 1.620, 95% CI was 1.443-1.818), malignant tumor ( HR = 1.604, 95% CI was 1.447-1.778), severe liver disease ( HR = 1.330, 95% CI was 1.157-1.530), use of vasoactive drugs within 24 hours ( HR = 1.213, 95% CI was 1.101-1.336), arterial partial pressure of oxygen (PaO 2; HR = 0.999, 95% CI was 0.998-1.000), blood lactic acid (Lac; HR = 1.066, 95% CI was 1.053-1.079), blood urea nitrogen (BUN) > 8.9 mmol/L ( HR = 1.257, 95% CI was 1.144-1.381), total bilirubin (TBil; HR = 1.023, 95% CI was 1.015-1.031), and prothrombin time (PT) > 14.5 s ( HR = 1.232, 95% CI was 1.127-1.347) were associated with the death of ICU patients with sepsis (all P < 0.05). Based on the above factors, a nomogram model was constructed, and the model validation results showed that the consistency index was 0.730. The calibration curve showed a good consistency between the predicted results of the nomogram model and observed results in the training and validation sets. ROC curve analysis showed that the area under the ROC curve (AUC) predicted by the nomogram model in the training set and the validation set for 28-day, 90-day and 1-year death risk was 0.771 (95% CI was 0.756-0.786) and 0.761 (95% CI was 0.738-0.784), 0.777 (95% CI was 0.763-0.791) and 0.765 (95% CI was 0.744-0.787), 0.677 (95% CI was 0.648-0.707) and 0.685 (95% CI was 0.641-0.728), respectively. DCA analysis showed that the nomogram model had significant net benefits in predicting 28-day, 90-day, and 1-year death risk, verifying the clinical value of the model and its good impact on actual decision-making. Conclusions:The death risk factors related to ICU patients with sepsis include age, SOFA score, SAPSⅡ score > 44, MAP ≤ 75 mmHg, RR, cerebrovascular disease, malignant tumors, severe liver disease, use of vasoactive drugs within 24 hours, PaO 2, Lac, BUN, TBil, PT > 14.5 s. The nomogram model constructed based on this can predict the death risk of ICU patients with sepsis.

Effects of interleukin-17A on liver and kidney injury and prognosis in septic mice / 中华危重病急救医学

OBJECTIVE@#To explore the effect of interleukin-17A (IL-17A) on liver and kidney injury and prognosis in septic mice.@*METHODS@#A total of 84 SPF male C57BL/6 mice were randomly divided into sham operation group (Sham group), cecal ligation and puncture (CLP) induced sepsis model group (CLP group), and IL-17A intervention group. IL-17A intervention group were then divided into five subgroups according to the dose of IL-17A (0.25, 0.5, 1, 2, 4 μg). Mice in the IL-17A intervention group were intraperitoneally injected with the corresponding dose of IL-17A 100 μL immediately after surgery. The other groups were intraperitoneally injected with 100 μL phosphate buffer solution (PBS). The survival rate of mice was observed at 7 days, and peripheral blood and liver, kidney and spleen tissues were collected. According to the 7-day survival, another 18 mice were randomly divided into Sham group, CLP group, and 1 μg IL-17A intervention group. Peripheral blood samples were collected at 12 hours and 24 hours after CLP, and the mice were sacrificed to obtain liver, kidney, and spleen tissues. The behavior and abdominal cavity of each group were observed. The levels of peripheral blood liver and kidney function indexes and inflammatory factors were detected. The histopathological changes of liver and kidney were observed under light microscope. The peripheral blood and spleen tissues were inoculated in the medium, the number of bacterial colonies was calculated, and the bacterial migration of each group was evaluated in vitro.@*RESULTS@#Except for the Sham group, the 7-day survival rate of mice in the 1 μg IL-17A intervention group was the highest (75.0%), so this condition was selected as the intervention condition for the subsequent study. Compared with Sham group, the liver and kidney functions of CLP group were significantly damaged at each time point after operation. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN) and serum creatinine (SCr) reached the peak at 24 hours after operation, and the liver and kidney pathological scores reached the peak at 7 days after operation, the levels of inflammatory cytokines interleukin (IL-17A, IL-6, IL-10) reached the peak at 12 hours after operation, and tumor necrosis factor-α (TNF-α) reached the peak at 24 hours after operation. In addition, a large number of bacteria proliferated in the peripheral blood and spleen, which reached the peak on day 7. Compared with the CLP group, exogenous administration of 1 μg IL-17A significantly delayed the rising trend of each index in the early stage of sepsis [24-hour ALT (U/L): 166.95±5.20 vs. 271.30±6.11, 24-hour AST (U/L): 599.42±7.25 vs. 1 013.27±3.37, 24-hour BUN (mg/L): 815.4±26.3 vs. 1 191.2±39.4, 24-hour SCr (μmol/L): 29.34±0.87 vs. 60.75±3.83, 7-day liver pathological score: 2.50 (2.00, 3.00) vs. 9.00 (8.50, 9.00), 7-day kidney pathological score: 1.00 (1.00, 2.00) vs. 5.00 (4.50, 5.00), 12-hour IL-17A (ng/L): 105.21±0.31 vs. 111.28±1.37, 12-hour IL-6 (ng/L): 83.22±1.01 vs. 108.88±0.99, 12-hour IL-10 (ng/L): 731.54±3.04 vs. 790.25±2.54, 24-hour TNF-α (μg/L): 454.67±0.66 vs. 576.18±0.76, 7-day peripheral blood colony count (CFU/mL): 600 (400, 600) vs. 4 200 (4 200, 4 300), 7-day spleen tissue colony count (CFU/g): 4 600 (4 400, 4 600) vs. 23 400 (23 200, 23 500), all P < 0.05].@*CONCLUSIONS@#Appropriate dose (1 μg) of exogenous IL-17A can reduce the lethal inflammatory response induced by CLP and improve the ability of bacterial clearance, thereby alleviating liver and kidney injury and improving the 7-day survival rate of septic mice.

Comparative study on nutritional status of patients in intensive care unit with different assessment tools / 中华危重病急救医学

Objective:To evaluate the nutritional status of patients in intensive care unit (ICU) by using nutritional risk screening 2002 scale (NRS2002), subjective general assessment (SGA) and critical illness nutritional risk score (NUTRIC), and to compare the characteristics and applicability of three scoring tools.Methods:A cross-sectional survey was conducted. 315 patients admitted to the comprehensive ICU of Affiliated Qingdao Municipal Hospital of Qingdao University from April 2018 to July 2019 were enrolled. Basic information of patients was collected, and patients were divided into two groups with 65 years old as the standard to compare the nutritional status of patients among different genders and ages. The nutritional status of patients were assessed by NRS2002, SGA, and NUTRIC. Height, weight, body mass index (BMI), triceps skinfold thickness (TSF), upper arm circumference (AC), leg circumference (LC), and other related parameters of human nutrition were measured. Total protein (TP), albumin (Alb), prealbumin (PA), serum creatinine (SCr), blood urea nitrogen (BUN), total cholesterol (TC), triglyceride (TG), total number of lymphocytes (LYM), hemoglobin (Hb), C-reactive protein (CRP) and other blood biochemical indicators were performed. Spearman rank correlation analysis was used to analyze the correlation between the three nutrition evaluation scales and other objective nutrition parameters. Binary multivariate Logistic regression analysis was used to evaluate the influencing factors of nutritional status with three scales of patients in ICU.Results:Among 315 patients in ICU, 183 were male and 132 were female. There were 143 patients < 65 years old and 172 ≥ 65 years old. In male patients, the acute physiology and chronic health evaluation Ⅱ (APACHEⅡ) score, age and BUN of patients aged ≥ 65 years old were significantly increased, and the height, weight, BMI, TSF, AC, LC, Alb and PA were significantly lowered as compared with those aged < 65 years old, while the difference in other indicators was not statistically significant. In the female patients, the APACHEⅡ score, age, SCr and BUN of the patients aged ≥ 65 years old were significantly increased, the height, Alb, PA and Hb were significantly decreased as compared with those aged < 65 years old, and the difference in other indicators was not statistically significant. The proportion of patients with nutritional risk evaluated by NRS2002 (NRS2002 score ≥ 3) was 87.62% (276/315). SGA showed that the proportion of malnourished patients (SGA was grade B or C) was 62.86% (198/315). NUTRIC showed 66.03% of patients (208/315) in high nutritional risk (NUTRIC score ≥ 5). Spearman rank correlation analysis showed that there were significant correlations among NRS2002, SGA and NUTRIC of patients in ICU ( rNRS2002 with SGA = 0.522, rNRS2002 with NUTRIC = 0.392, rSGA with NUTRIC = 0.442, all P < 0.01). Among the three assessment tools, SGA had the best correlation with blood biochemical indicators and body measurements to assess nutritional status, followed by NRS2002, and NUTRIC had the worst correlation. Binary multivariate Logistic regression showed that APACHEⅡ score, BMI, AC, BUN and TG were factors influencing NRS2002 assessment of nutritional status in ICU patients [odds ratio ( OR) were 2.535, 0.404, 1.438, 0.858, and 2.391, respectively, all P < 0.05]; APACHEⅡ score, age, weight, TP, BUN, LYM and CRP were influence factors of SGA for evaluating the malnutrition of patients in ICU ( OR values were 1.074, 1.038, 0.921, 0.947, 1.077, 1.625 and 0.991, respectively, all P < 0.05); APACHEⅡ score, age, LYM and CRP were the influence factors of NUTRIC assessment for malnutrition of patients in ICU ( OR values were 1.159, 1.049, 0.715 and 0.995, respectively, all P < 0.05). Conclusions:The nutrition status of ICU patients evaluated by NRS2002, SGA and NUTRIC was simple and easy to operate, and the positive screening rate of NRS2002 was the highest, which was suitable for patients with mild conditions in ICU. SGA is the most valuable tool to evaluate the nutritional status of ICU patients. NUTRIC has a poor correlation with objective indicators reflecting nutritional status, while its indicators are objective and easy to obtain, which is suitable for ICU patients with critical condition and unclear consciousness. Nutritional assessment tools should be integrated with the patient's gender, age, anthropometric and biochemical indicators.

Effects of aerosol inhalation on respiratory mechanical parameters under different ventilation patterns and ventilator parameters / 中华危重病急救医学

Objective To investigate the effects of aerosol inhalation on respiratory mechanical parameters under different ventilation patterns and ventilator parameters in patients on mechanical ventilation and simulated model of aqualung in vitro. Methods ① Clinical research: the patients needed sedative undergoing mechanical ventilation admitted to intensive care unit (ICU) of Qingdao Municipal Hospital from January 2016 to January 2018 were enrolled. They were randomly divided into volume controlled ventilation (VCV) group and pressure controlled ventilation (PCV) group according to random number table. Main parameters setting of respirator: the predetermined tidal volume (VT) was set at 500 mL in the VCV group; the preset pressure was regulated, so that when the atomizer was connected to the atomization device, the VT was nearly equal to or slightly larger than 500 mL in the PCV group. Respiratory mechanical indices [peak airway pressure (Ppeak), inspiratory tidal volume (VTi), exhaled tidal volume (VTe)] were recorded before atomization (atomized oxygen flow was 0) and 10 minutes after the beginning of atomization under the condition of 7 L/min and 9 L/min of atomized oxygen flow respectively. ② Simulated scuba test in vitro: the ventilator was connected to the simulated scuba, and an external mechanical ventilation model was constructed. They were divided into VCV group and PCV group according to ventilation mode. Main parameters setting of respirator: VCV group was given 450, 550, 650 mL preset VT, and PCV group was given 12, 16, 20 cmH2O (1 cmH2O = 0.098 kPa) preset suction pressure. The changes in respiratory mechanical indexes were observed under different ventilation patterns and ventilator parameters of 0 (only connected with atomizing device), 5, 7, 9 L/min atomizing oxygen flow. Results ① Clinical research results: all 77 patients were enrolled in the final analysis, including 20 patients with 7 L/min of atomized oxygen flow under VCV mode, 18 patients with 9 L/min of atomized oxygen flow, and 21 patients with 7 L/min of atomized oxygen flow under PCV mode and 18 patients with 9 L/min of atomized oxygen flow. Under VCV mode, the levels of Ppeak and VTe were increased with the increase in atomized oxygen flow, and there was significant difference at 9 L/min as compared with those before atomization [Ppeak (cmH2O): 29.44±4.58 vs. 24.39±4.64, VTe (mL): 896.26±24.91 vs. 497.61±8.67, both P < 0.05]. There was no significant change in VTi, and no significant difference at 9 L/min of atomized oxygen flow as compared with that before atomization (mL: 494.67±3.07 vs. 492.61±6.05, P > 0.05). Under PCV mode, with the increase in oxygen atomization flow, VTi was decreased gradually, and VTe was increased gradually, with significant difference as compared with those before atomization when the atomized oxygen flow was 9 L/min [VTi (mL): 322.78±17.75 vs. 518.17±8.97, VTe (mL): 730.89±31.20 vs. 519.00±9.06, both P < 0.05]. There was no significant change in Ppeak, and no significant difference at 9 L/min of atomized oxygen flow as compared with that before atomization (cmH2O: 21.44±2.23 vs. 21.39±2.55, P > 0.05). ② Simulated scuba results in vitro: under VCV mode, VTe monitored by respirator and VT showed by simulated scuba in different preset VT groups were continuously increased with the increase in oxygen atomization flow, while VTi monitored by ventilator was not significantly changed. At 10 minutes after the beginning of atomization, the VTi monitored by ventilator in different preset VT groups was significantly lower than VT showed by simulated water lung (mL: 649.67±5.03 vs. 840.00±10.00 at 650 mL of preset VT and 9 L/min of atomized oxygen flow, P < 0.05), and VTe was significantly higher than VT showed by simulated water lung (mL: 1 270.33±11.06 vs. 840.00±10.00 at 650 mL of preset VT and 9 L/min of atomized oxygen flow, P < 0.05). Under PCV mode, with the increase in atomized oxygen flow, VTi monitored by ventilator in different preset suction pressure groups was decreased gradually, and VTe was increased gradually, but Ppeak monitored by ventilator did not changed significantly. At 10 minutes after the beginning of atomization, the VTi monitored by ventilator in different preset suction pressure groups was significantly lower than VT showed by simulated water lung (mL: 917.33±4.51 vs. 1 103.33±5.77 at 20 cmH2O of preset suction pressure and 9 L/min of atomized oxygen flow, P < 0.05), and VTe was significantly higher than VT showed by simulated water lung (mL: 1 433.33±4.73 vs. 1 103.33±5.77 at 20 cmH2O of preset suction pressure and 9 L/min of atomized oxygen flow, P < 0.05). Conclusions Under the VCV mode, the oxygen flow outside the atomization could lead to the increase in VT of the patient side, while under the PCV mode, the VT and Ppeak in the patient side had no significant change. Both VTi and VTe monitored by ventilator could not reflect the patient's VT under either VCV or PCV mode.

Screening and activity verification of monoclonal antibody against PcrV protein of pseudomonas aeruginosa / 中国免疫学杂志

Objective:To obtain a high specificity and high affinity anti-PcrV protein monoclonal antibody which can be used for the treatment of Pseudomonas aeruginosa infected.Methods: The PcrV gene was amplified by PCR using P.aeruginosa PAO1 genome DNA as the template.The expression vector(pET-28a-PcrV) was constructed and transformed into E.coli BL21(DE3).The re-combinant PcrV protein was expressed by IPTG induction and purified by Ni2+affinity chromatography.The specific binders of PcrV were screened by phage display.The genes encoding VH and VL were amplified respectively by PCR using the plasmid of positive clone as the template.Then the recombinant expression vectors were constructed and transfected into 293E cells.Monoclonal antibody were purified by the Protein A affinity resin from the culture supernatants.The affinity of antibody was detected by ELISA and the function of YG5 was verified in murine pneumonia model caused by P.aeruginosa.Results: Recombinant PcrV protein was expressed and purified.A full human monoclonal antibody(named as YG5) against PcrV was obtained by phage display.The results of ELISA showed that YG5 had a high affinity with EC50=61 ng/ml.Furthermore,it was found that YG5 could protect mice from infection caused by P.aeruginosa.Conclusion:Our findings present a novel human monoclonal antibody YG5 against PcrV,which inhibits the infection casued by P.aeruginosa and may be a potential drug for treatment of P.aeruginosa infection.

Effects of lentivirus-mediated heat shock protein 70 gene on endoplasmic reticulum calcium homeostasis and calcium channels of PC12 cells induced by ischemia and hypoxia / 中华危重病急救医学

Objective To investigate the effects of lentivirus-mediated heat shock protein 70 (HSP70) gene on calcium homeostasis and calcium channels of PC12 cells induced by ischemic and hypoxia and its mechanisms. Methods PC12 cells at logarithmic phase were collected, and they were divided into recombined lentiviral infection group [infected by lentivirus containing HSP70 and green fluorescent protein (GFP) fluorescin gene], lentivirus control group (infected by lentivirus containing GFP without HSP70 gene) and non-infection group. PC12 cells were subjected ischemia/hypoxia for 4, 8, 12, 24 hours, and the cell activity was determined by methylthiazolyl tetrazolium (MTT) assay test inorder to determine the best time for ischemia/hypoxia. The mRNA expressions of HSP70, muscle/endoplasmic reticulum Ca2+-ATP isoforms (SERCA2a, SERCA2b), ryanodine receptor 2 (RyR2), and inositol 1,4,5-triphosphate receptor 1 (IP3R1) were determined by real-time quantitative reverse transcription-polymerase chain reaction (RT-qPCR), and the protein expressions of HSP70, SERCA, and IP3R were determined by Western Blot at 8 hours after ischemic/hypoxia. Flow cytometry was used to determine the levels of intracellular reactive oxygen (ROS) and intracellular Ca2+ ([Ca2+]i). Results With the prolongation of time of ischemia/hypoxia, the cell viability in all groups showed an increase followed by a weakening, and peaked at 8 hours. The cell viability at 8 hours in lentiviral infection group was significantly higher than that of the non-infection group and lentivirus control group [A value (×10-2): 20.3±2.2 vs. 14.1±2.1, 15.0±1.6, both P 0.05]; the relative fluorescence intensity of ROS and [Ca2+]i in lentiviral infection group was significantly reduced (ROS: 30.54±1.23 vs. 58.03±1.97, 57.72±2.35; [Ca2+]i: 34.50±2.05 vs. 48.20±3.02, 46.80±2.75, all P < 0.01]. Conclusion Exogenous HSP70 can maintain calcium homeostasis in the endoplasmic reticulum of PC12 cells, affect the Ca2+ channel protein regulated by calcium channel IP3R and calcium pump SERCA, which may cause hypoxia/ischemia intracellular injury.

Effects of delayed sowing-date on yield components of Thladiantha setispina / 中草药

Objective: In order to discuss the influence difference of environmental stress on dioecious plants and the response of environmental factors influence on the fruiting and yield of Thladiantha setispina. Methods: The effects of the different sowing-dates on the female plant rate, fruit character, and seed yield of T. setispina were investigated by the comparative ways. Results: Different sowing-dates on differentiation of male and female plants had a significant impact. The appropriate delay of sowing-date could significantly improve the proportion of female T. setispina (P 0.05), but the sowing-date on yield components of T. setispina had a direct impact on related indicators, yield differences during the treatments reached a very significant level (P < 0.01). Conclusion: The appropriate delaying of sowing-date could help to improve the seed production of T. setispina.

Proficiency Testing of Three Organochlorine Pesticides Determination in Vegetable Oils in Laboratories in China / 环境与健康杂志

Objective To understand the testing capability for organochlorine pesticides of the food inspection labs in China. Methods The CNCA organized the proficiency testing(PT) of determination of heptachlor, aldrin and dieldrin in the vegetable oils. 21 labs from 14 provinces (cities) took part in the PT. The GC method prescribed by official method of AOAC was recommended, other method was also permitted. Results The PT showed that 81.0%-85.7% labs presented satisfactory results, 9.5% had questionable results and 4.8%-9.5% had dissatisfactory results. Conclusion Most of the labs that took part in the PT have good competence in analyzing organochlorine pesticides.