Development and evaluation of an online monitoring single-particle optical particle counter with polarization detection.

We developed a single-particle optical particle counter with polarization detection (SOPC) for the real-time measurement of the optical size and depolarization ratio (defined as the ratio of the vertical component to the parallel component of backward scattering) of atmospheric particles, the polarization ratio (DR) value can reflect the irregularity of the particles. The SOPC can detect aerosol particles with size larger than 500 nm and the maximum particle count rate reaches ∼1.8 × 105 particles per liter. The SOPC uses a modulated polarization laser to measure the optical size of particles according to forward scattering signal and the DR value of the particles by backward S and P signal components. The sampling rate of the SOPC was 106 #/(sec·channel), and all the raw data were processed online. The calibration curve was obtained by polystyrene latex spheres with sizes of 0.5-10 µm, and the average relative deviation of measurement was 3.96% for sub 3 µm particles. T-matrix method calculations showed that the DR value of backscatter light at 120° could describe the variations in the aspect ratio of particles in the above size range. We performed insitu observations for the evaluation of the SOPC, the mass concentration constructed by the SOPC showed good agreement with the PM2.5 measurements in a nearby state-controlled monitoring site. This instrument could provide useful data for source appointment and regulations against air pollution.

Comparison of ultrasound-guided and traditional localisation in intraspinal anesthesia: a systematic review and network meta-analysis.

OBJECTIVES: The optimal puncture technique for neuraxial anaesthesia in different populations is unclear. We sought to obtain data from randomised controlled trials comparing the impact of ultrasound-guided technology and traditional positioning technology on the success rate of neuraxial anaesthesia. DESIGN: Systematic review and network meta-analysis using study populations, interventions, intervention comparisons, outcome measures and study types. DATA SOURCES: PubMed, Embase, Cochrane Library and Web of science were searched until 31 September 2022. ELIGIBILITY CRITERIA: We included randomised controlled trials comparing three types of neuraxial anaesthesia: ultrasound-assisted, ultrasound real-time guidance and conventional positioning to describe which neuraxial anaesthesia modality is best for patients and to recommend the appropriate one for different populations. DATA EXTRACTION AND SYNTHESIS: Five independent reviewers retrieved, screened and edited included studies using standardised methods. Assess risk of bias using the Cochrane Collaboration and Evidence Project tools. Network meta-analysis was performed using STATA V.15 statistical software. RESULTS: Twenty-two studies containing three different interventions were included. The SUCRA values of first-pass success rates for the three neuraxial anaesthesia methods were real-time guidance (82.8%), ultrasound-assisted (67.1%) and traditional positioning (0.1%). Both ultrasound techniques improved first-pass success rates compared with traditional localization, but there was no significant difference between the two. Subgroup analysis showed that the use of real-time ultrasound guidance for neuraxial anaesthesia in pregnant and patients with obesity improved first-pass success rates. Ultrasound-assisted technology can improve first-attempt success rates in older patients with abnormal lumbar spine anatomy. CONCLUSION: Compared with conventional positioning, ultrasound guidance technology can improve the first-pass success rate of neuraxial anaesthesia, but there is no significant difference between ultrasound-assisted and real-time guidance technology. The results of subgroup analysis tell us that the most suitable neuraxial anaesthesia method is different for different groups of people. PROSPERO REGISTRATION NUMBER: PROSPERO number: CRD42022376041.

Effect of perioperative acupoint electrical stimulation on macrophages in mice under operative stress.

The strong perioperative stress response caused by surgical anesthesia can significantly suppress immune function, and the body is in a state of immunosuppression for 3 to 4 days after surgery, which leads to an increase in the probability of postoperative infection. Traditional Chinese medicine believes that acupuncture points can "reconcile yin and yang", promote the recovery of immune function, and help reduce the incidence of postoperative infection. Macrophages are an important type of immune cells that participate in the body's innate immunity. They have powerful phagocytosis and clearance functions. They can be polarized into M1 and M2 types under the regulation of the body, and play different roles in fighting microbial infections. Among them, the M1 type can participate in the elimination of pathogens. In this study, we will investigate the perioperative acupoint electrical stimulation to alleviate the immunosuppressive state of surgical stress mice, clarify the regulation of perioperative acupoint electrical stimulation on glucocorticoids and the relationship between NF-κB molecules and macrophage polarization.The key molecules of related pathways were verified by glucocorticoid receptor inhibitors, and it was found that electrical stimulation of acupoints during the perioperative period can affect the polarization of macrophages in surgically stressed mice to the M1 type by reducing the level of glucocorticoids and promoting the expression of NF κB molecules. Further reveal the partial mechanism of electroacupuncture regulating the anti-inflammatory and pro-inflammatory processes of macrophages in the immune response.

[Relationship between "1-hour serum lactate" level and 30-day mortality in critical care patients in intensive care unit].

OBJECTIVE: To investigate the relationship between 1-hour lactate (1 h Lac) and 30-day mortality in critical care patients in intensive care unit (ICU). METHODS: A retrospective, observational cohort study was performed with adult critical patients (age ≥ 16 years old) having lactate records within 1 hour after ICU admission from Medical Information Mart for Intensive Care-III database (MIMIC-III). According to the 1 h Lac level, the patients were divided into three groups: < 2 mmol/L, 2-4 mmol/L, and > 4 mmol/L groups. The baseline characteristics were analyzed. Multivariable Logistic regression analysis was performed to assess the association between 1 h Lac and 30-day mortality. The receiver operating characteristic (ROC) curve was used to analyze the predictive value of 1 h Lac for 30-day mortality, and Kaplan-Meier survival curve was performed according to the best cut-off value. In addition, sensitivity analysis was carried out for each classification variable. RESULTS: A total of 3 969 ICU patients were included, with 673 died in 30 days, and the total mortality was 16.95%. There were 1 664, 1 588, 717 patients in Lac < 2 mmol/L, 2-4 mmol/L and > 4 mmol/L group, respectively. There were significant differences in age, ICU duration, ICU type, heart rate, leukocyte count, hemoglobin, creatinine, sequential organ failure score (SOFA), ventilator application, vasoactive drug use and main diagnosis among the three groups. Multivariable Logistic regression analysis showed that a 1 mmol/L increment in Lac was associated with 0.24 times higher risk of 30-day mortality [odds ratio (OR) = 1.24, 95% confidence interval (95%CI) was 1.19-1.29, P < 0.000 1]. ROC curve analysis showed that the area under ROC curve (AUC) of 1 h Lac for predicting 30-day mortality of severe patients was 0.694 (95%CI was 0.669-0.718). The cut-off value was 3.35 mmol/L with sensitivity of 0.499 and specificity of 0.779, whilst positive likelihood ratio was 2.260, and negative likelihood ratio was 0.643. According to the cut-off value of 1 h Lac, the patients were divided into high lactate group (≥ 3.35 mmol/L) and low lactate group (< 3.35 mmol/L). In the two subgroups, 30-day mortality was 31.58% (336/1 064) and 11.60% (337/2 905), respectively. The Kaplan-Meier survival curve showed that the 30-day cumulative survival rate of high lactate group was significantly lower than that of low lactate group (Log-rank test: χ2 = 247.72, P < 0.000 1). Multiple Logistic regression analysis showed that the 30-day mortality rate of high lactate group was 2.34 times that the level of low lactate group (OR = 2.34, 95%CI was 1.90-2.88, P < 0.000 1), after the adjustment of age, time of admission, type of ICU, hemoglobin, leukocyte count, use of vasopressor, use of ventilator and main diagnosis of patients. Stratified analysis showed that the relationship between 1 h Lac and 30-day mortality was stable. CONCLUSIONS: 1 h Lac is associated with 30-day mortality in critical care patients. The risk of death was significantly increased in critically ill patients with 1 h Lac higher than 3.35 mmol/L.

[The interaction between soluble CD73 and 90-day mortality from patients with non-septic shock and sepsis shock: a secondary analysis from the prospective FINNAKI study].

OBJECTIVE: Fundamental researches have shown that soluble CD73 (sCD73) can inhibit inflammatory response and limit excessive tissue damage caused by continuous immune cell activation. A Finnish prospective, observational study of acute kidney injury (FINNAKI) showed no association between sCD73 and 90-day mortality in sepsis patients. Clinical data of this study was used for secondary analysis to explore whether the relationship between sCD73 and 90-day mortality was consistent in septic shock and non-septic shock patients. METHODS: The FINNAKI study was a prospective, observational cohort study conducted in 17 intensive care units (ICUs) in Finland from September 1st, 2011 to February 1st, 2012. Sepsis/septic shock was defined according to Sepsis-1 definition. Demographic characteristics, treatment, comorbidities and 90-day mortality of the patients were analyzed. To evaluate the difference (interaction test) between the relationship of sCD73 and 90-day mortality in septic shock and non-septic shock patients, likelihood ratio test was used to integrate the product term (sCD73×septic shock or non-septic shock) into multivariable Logistic regression. Sensitivity analysis was performed with the definition of Sepsis-3. The interaction between sCD73 and 90-day mortality in patients with septic shock and non-septic shock were verified by generalized additive model (GAM). RESULTS: A total of 588 patients with severe sepsis/septic shock were enrolled. 164 patients died in 90 days, and the 90-day mortality was 27.89%. Based on the Sepsis-1 definition, there were 159 non-septic shock patients and 429 septic shock patients. Compared with the non-septic shock patients, lactate (Lac) level, sequential organ failure assessment (SOFA) score, fluid balance on the first day, and ratio of mechanical ventilation, 12-hour acute kidney injury (AKI), renal replacement therapy (RRT), and postoperative ICU transition in the septic shock patients were significantly increased and the proportion of emergency admission to ICU was significantly decreased. Based on the Sepsis-3 definition, there were 383 non-septic shock patients and 205 septic shock patients; the results of clinical data analysis between the two groups were similar to those based on Sepsis-1. Based on Sepsis-1, there was no significant difference in 90-day mortality between non-septic shock and septic shock patients [23.90% (38/159) vs. 29.37% (126/429), P > 0.05]. However, based on Sepsis-3, the 90-day mortality of patients with septic shock was significantly higher than that of patients with non-septic shock [37.56% (77/205) vs. 22.72% (87/383), P < 0.01]. Multivariate Logistic regression analysis and interaction test showed that after adjusting all confounding factors (except the number of complications) in non-sepsis shock and sepsis shock patients, sCD73 and 90-day mortality were significantly different in both Sepsis-1 and Sepsis-3. The P values for interaction tests were 0.046 and 0.027, respectively. In patients with non-septic shock, sCD73 tended to be positively associated with 90-day mortality [Sepsis-1: odds ratio (OR) = 1.46, 95% confidence interval (95%CI) was 0.99-2.13, P = 0.053; Sepsis-3: OR = 1.34, 95%CI was 1.02-1.74, P = 0.034]. In septic shock patients, sCD73 tended to be negatively associated with 90-day mortality (Sepsis-1: OR = 0.91, 95%CI was 0.69-1.20, P = 0.494; Sepsis-3: OR = 0.80, 95%CI was 0.55-1.17, P = 0.249). The results of GAM model validation were consistent with the results of Logistic regression equation cross validation. CONCLUSIONS: The relationship between sCD73 and 90-day mortality is significantly different from patients with non-sepsis shock and sepsis shock. In patients with non-sepsis shock, sCD73 is trend to positively associated with 90-day mortality, and there is a negative trend between sCD73 and 90-day mortality in patients with septic shock.