[Study on formulation and revision of detection methods of "Standards for indoor air quality (GB/T 18883-2022)" in China].

The formulation and revision of the detection methods of indoor air quality standards is an important, rigorous and delicate endeavor. This paper introduced the formulation and revision of the detection methods of the standards for indoor air quality (GB/T 18883-2022), focusing on the revision process, revision principles, main adjustments and technical points of some key indicators to facilitate users to better understand and apply the detection methods in standards for indoor air quality (GB/T 18883-2022).

[Outcome of surgical repair for aortic coarctation with coexisting descending aortic aneurysm in adult patients].

Objective: To evaluate the efficacy of surgical treatment of aortic coarctation combined with descending aortic aneurysm in adult patients. Methods: This is a retrospective cohort study. Adult patients with aortic coarctation who were hospitalized in Beijing Anzhen Hospital from January 2015 to April 2019 were enrolled. The aortic coarctation was diagnosed by aortic CT angiography, and the included patients were divided into the combined descending aortic aneurysm group and the uncomplicated descending aortic aneurysm group based on descending aortic diameter. General clinical data and surgery-related data were collected from the included patients, and death and complications were recorded at 30 days after surgery, and upper limb systolic blood pressure was measured in all patients at discharge. Patients were followed up after discharge by outpatient visit or telephone call for their survival and the occurrence of repeat interventions and adverse events, which included death, cerebrovascular events, transient ischemic attack, myocardial infarction, hypertension, postoperative restenosis, and other cardiovascular-related interventions. Results: A total of 107 patients with aortic coarctation aged (34.1±15.2) years were included, and 68 (63.6%) were males. There were 16 cases in the combined descending aortic aneurysm group and 91 cases in the uncomplicated descending aortic aneurysm group. In the combined descending aortic aneurysm group, 6 cases (6/16) underwent artificial vessel bypass, 4 cases (4/16) underwent thoracic aortic artificial vessel replacement, 4 cases (4/16) underwent aortic arch replacement+elephant trunk procedure, and 2 cases (2/16) underwent thoracic endovascular aneurysm repair. There was no statistically significant difference between the two groups in the choice of surgical approach (all P>0.05). In the combined descending aortic aneurysm group at 30 days after surgery, one case underwent re-thoracotomy surgery, one case developed incomplete paraplegia of the lower extremity, and one case died; and the differences in the incidence of endpoint events at 30 days after surgery were similar between the two groups (P>0.05). Systolic blood pressure in the upper extremity at discharge was significantly lower in both groups compared with the preoperative period (in the combined descending aortic aneurysm group: (127.3±16.3) mmHg vs. (140.9±16.3) mmHg, P=0.030, 1 mmHg=0.133 kPa; in the uncomplicated descending aortic aneurysm group: (120.7±13.2) mmHg vs. (151.8±26.3) mmHg, P=0.001). The follow-up time was 3.5 (3.1, 4.4) years. There were no new deaths in the combined descending aortic aneurysm group, no transient ischemic attack, myocardial infarction or re-thoracotomy surgery, and one patient (1/15) suffered cerebral infarction and 10 patients (10/15) were diagnosed with hypertension. The differences in the occurrence of endpoint events during postoperative follow-up were similar between the two groups (P>0.05). Conclusion: In experienced centers, long-term prognosis of patients with aortic coarctation combined with descending aortic aneurysm is satisfactory post surgical intervention.

[Role of functional hydrogel in promoting wound healing].

Cutaneous wounds are one of the commonest clinical diseases. At present, there are still many challenges in how to repair wounds quickly with high quality. With the rapid development and cross-integration of materials science and biomedicine, hydrogels that can integrate various excellent properties through flexible structural modification and combination of different functional components are widely applied in wound management and research. This paper attempted to summarize the role of hydrogel in promoting wound repair from the respects of matrix materials, special structures, and diverse functions of hydrogel.

[Effects of interleukin-4-modified gold nanozymes on the full-thickness skin defects in diabetic mice].

Objective: To investigate the effects and mechanism of interleukin-4-modified gold nanoparticle (IL-4-AuNP) on the wound healing of full-thickness skin defects in diabetic mice. Methods: Experimental research methods were adopted. Gold nanoparticle (AuNP) and IL-4-AuNP were synthesized by improving the methods described in published literature. The morphology of those two particles were photographed by transmission electron microscopy, and their particle sizes were calculated. The surface potential and hydration particle size of the two particles were detected by nanoparticle potentiometer and particle size analyzer, respectively. The clearance rate of IL-4-AuNP to hydrogen peroxide and superoxide anion was measured by hydrogen peroxide and superoxide anion kits, respectively. Mouse fibroblast line 3T3 cells were used and divided into the following groups by the random number table (the same below): blank control group, hydrogen peroxide alone group treated with hydrogen peroxide only, hydrogen peroxide+IL-4-AuNP group treated with IL-4-AuNP for 0.5 h and then treated with hydrogen peroxide. After 24 h of culture, the reactive oxygen species (ROS) levels of cells were detected by immunofluorescence method; cell count kit 8 was used to detect relative cell survival rate. The macrophage Raw264.7 mouse cells were then used and divided into blank control group and IL-4-AuNP group that treated with IL-4-AuNP. After 24 h of culture, the expression of arginase 1 (Arg-1) in cells was observed by immunofluorescence method. Twelve male BALB/c mice (mouse age, sex, and strain, the same below) aged 8 to 10 weeks were divided into IL-4-AuNP group and blank control group, treated accordingly. On the 16th day of treatment, whole blood samples were collected from mice for analysis of white blood cell count (WBC), red blood cell count (RBC), hemoglobin level, or platelet count and the level of aspartate aminotransferase (AST), alanine transaminase (ALT), urea, or creatinine. The inflammation, bleeding, or necrosis in the heart, liver, spleen, lung, and kidney tissue of mice were detected by hematoxylin-eosin (HE). Another 36 mice were selected to make diabetic model, and the full-thickness skin defect wounds were made on the back of these mice. The wounds were divided into blank control group, AuNP alone group, and IL-4-AuNP group, with 12 mice in each group, and treated accordingly. On the 0 (immediately), 4th, 9th, and 15th day of treatment, the wound condition was observed and the wound area was calculated. On the 9th day of treatment, HE staining was used to detect the length of neonatal epithelium and the thickness of granulation tissue in the wound. On the 15th day of treatment, immunofluorescence method was used to detect ROS level and the number of Arg-1 positive cells in the wound tissue. The number of samples was 6 in all cases. Data were statistically analyzed with independent sample t test, corrected t test, Tukey test, or Dunnett T3 test. Results: The size of prepared AuNP and IL-4-AuNP were uniform. The particle size, surface potential, and hydration particle size of AuNP and IL-4-AuNP were (13.0±2.1) and (13.9±2.5) nm, (-45.8±3.2) and (-20.3±2.2) mV, (14±3) and (16±4) nm, respectively. For IL-4-AuNP, the clearance rate to hydrogen peroxide and superoxide anion were (69±4)% and (52±5)%, respectively. After 24 h of culture, the ROS level of 3T3 in hydrogen peroxide alone group was significantly higher than that in blank control group (q=26.12, P<0.05); the ROS level of hydrogen peroxide+IL-4-AuNP group was significantly lower than that in hydrogen peroxide alone group (q=25.12, P<0.05) and close to that in blank control group (P>0.05). After 24 h of culture, the relative survival rate of 3T3 cells in hydrogen peroxide+IL-4-AuNP group was significantly higher than that in hydrogen peroxide alone group (t=51.44, P<0.05). After 24 h of culture, Arg-1 expression of Raw264.7 cells in IL-4-AuNP group was significantly higher than that in blank control group (t'=8.83, P<0.05).On the 16th day of treatment, there were no significant statistically differences in WBC, RBC, hemoglobin level, or platelet count and the level of AST, ALT, urea, or creatinine of mice between blank control group and IL-4-AuNP group (P>0.05). No obvious inflammation, bleeding or necrosis was observed in the heart, liver, spleen, lung, and kidney of important organs in IL-4-AuNP group, and no significant changes were observed compared with blank control group. On the 0 and 4th day of treatment, the wound area of diabetic mice in blank control group, AuNP alone group, and IL-4-AuNP group had no significant difference (P>0.05). On the 9th day of treatment, the wound areas both in AuNP alone group and IL-4-AuNP group were significantly smaller than that in blank control group (with q values of 9.45 and 14.87, respectively, P<0.05), the wound area in IL-4-AuNP group was significantly smaller than that in AuNP alone group (q=5.42, P<0.05). On the 15th day of treatment, the wound areas both in AuNP alone group and IL-4-AuNP group were significantly smaller than that in blank control group (with q values of 4.84 and 20.64, respectively, P<0.05), the wound area in IL-4-AuNP group was significantly smaller than that in AuNP alone group (q=15.80, P<0.05); moreover, inflammations such as redness and swelling were significantly reduced in IL-4-AuNP group compared with the other two groups. On the 9th day of treatment, compared with blank control group and AuNP alone group, the length of neonatal epithelium in the wound of diabetic mice in IL-4-AuNP group was significantly longer (all P<0.05), and the thickness of the granulation tissue in the wound was significantly increased (with q values of 11.33 and 9.65, respectively, all P<0.05). On the 15th day of treatment, compared with blank control group, ROS levels in wound tissue of diabetic mice in AuNP alone group and IL-4-AuNP group were significantly decreased (P<0.05). On the 15th day of treatment, the number of Arg-1 positive cells in the wounds of diabetic mice in IL-4-AuNP group was significantly more than that in blank control group and AuNP alone group, respectively (all P<0.05). Conclusions: IL-4-AuNP is safe in vivo, and can improve the oxidative microenvironment by removing ROS and induce macrophage polarization towards M2 phenotype, thus promote efficient diabetic wound healing and regeneration of full-thickness skin defects in diabetic mice.

[Mediation effect of inflammatory biomarkers on the association between blood lead levels and blood pressure changes in Chinese adults].

Objective: To investigate the role of inflammatory biomarkers in the relationship between blood lead levels and blood pressure changes. Methods: A total of 9 910 people aged 18-79 years who participated in the China National Human Biomonitoring in 2017-2018 were included in this study. A self-made questionnaire was used to collect demographic characteristics, lifestyle and other information, and the data including height, weight and blood pressure were determined through physical examination. Blood and urinary samples were collected for the detection of blood lead and cadmium levels, urinary arsenic levels, white blood cells, neutrophils, lymphocytes, and hypersensitive C-reactive protein (hs-CRP). Weighted linear regression models were used to evaluate the associations between blood lead, inflammatory biomarkers and blood pressure. Mediation analysis was performed to investigate the role of inflammation in the relationship between blood lead levels and blood pressure changes. Results: The median (Q1, Q3) age of all participants was 45.4 (33.8, 58.4)years, including 4 984 males accounting for 50.3%. Multivariate logistic regression model analysis showed that after adjusting for age, gender, residence area, BMI, education level, smoking and drinking status, family history of hypertension, consumption frequency of rice, vegetables, and red meat, fasting blood glucose, total cholesterol, triglycerides, blood cadmium and urinary arsenic levels, there was a positive association between blood lead levels, inflammatory biomarkers and blood pressure (P<0.05). Each 2.71 µg/L (log-transformed) increase of the lead was associated with a 2.05 (95%CI: 0.58, 3.53) mmHg elevation in systolic blood pressure (SBP), 2.24 (95%CI: 1.34, 3.14) mmHg elevation in diastolic blood pressure (DBP), 0.25 (95%CI: 0.05, 0.46) mg/L elevation in hs-CRP, 0.16 (95%CI: 0.03, 0.29)×109/L elevation in white blood cells, and 0.11 (95%CI: 0.02, 0.21)×109/L elevation in lymphocytes, respectively. Mediation analysis showed that the levels of hs-CRP significantly mediated the association of blood lead with SBP, with a proportion about 3.88% (95%CI: 0.45%, 7.32%). The analysis also found that the levels of hs-CRP and neutrophils significantly mediated the association of blood lead with SBP, with a proportion about 4.10% (95%CI: 1.11%, 7.10%) and 2.42% (95%CI: 0.07%, 4.76%), respectively. Conclusion: This study suggests that inflammatory biomarkers could significantly mediate the association of blood lead levels and blood pressure changes.

[The applications and challenges of liquid chromatography tandem mass spectrometry in maternal and child health].

Due to its ultra-high sensitivity, specificity and throughput, liquid chromatography tandem mass spectrometry (LC-MS/MS) has become an important analytical tool in clinical laboratories in quantifying various small molecules, such as vitamins, bile acids, steroids and other internal metabolites relevant to maternal diseases. As an effective means of screening and diagnosing diseases in preventive medicine, LC-MS/MS has been widely used in maternal and child health, contributing to the reduction of the incidence of maternal and child diseases and premature morbidity and mortality. At present, LC-MS/MS is an emerging and powerful platform in laboratory testing in China, facing both challenges and opportunities. In this article, the representative applications in the field of maternal and child health are summarized and discussed, along with the major hurdles of LC-MS/MS in clinical recognition and implementation.

[Clinical study of digital six-axis external fixation frame based on CT data for tibiofibular fractures].

Objective: To investigate the clinical effect of applying the digital six-axis external fixation frame based on CT data in the treatment of tibiofibular fractures. Methods: The clinical data of 43 patients with tibiofibular fractures treated by the self-developed digital six-axis external fixation frame based on CT data at Integrated Orthopedic Department of Traditional Chinese Medicine (TCM) and Western Medicine,HongHui Hospital from January 2018 to January 2021 were retrospective analysis.There were 27 males and 16 females,aged (36.0±9.4) years(range:25 to 50 years).AO classification:15 cases of 42A,11 cases of 42B, and 17 cases of 42C.There were 7 open fractures and Gustilo fracture classification:2 cases of type Ⅰ,4 cases of type Ⅱ,and 1 case of type Ⅲ.The two or three plane rings were connected with six connecting rods to form a complete six-axis external fixation frame,and the distal and proximal fracture blocks were connected to the distal and proximal rings by fixation pins,and the lengths of the six connecting rods needed to be adjusted were calculated by using the supporting software according to the CT data after surgery,and then the lengths of the connecting rods were adjusted one by one to complete the reduction of the fracture. The reduction accuracy of this six-axis external fixation brace was evaluated by measuring postoperative radiographs; postoperative recovery and complications were collected,the time of brace removal was recorded,and the function of the affected limb was evaluated according to the Johner-Wruhs score at the final follow-up. Results: Postoperative radiographs showed that all patients achieved satisfactory reduction with lateral displacement(M(IQR)) of 2.3(2.5) mm (range:0.3 to 7.3 mm),anteroposterior displacement of 2.1 (2.4) mm (range:0.3 to 5.7 mm),anteroposterior angulation of 2.5(2.4)°(range:0 to 5°),internal and external angulation of 2.1(1.5)°(range:0 to 4°), and no significant internal or external rotational deformity was detected on the exterior.On the second postoperative day,all patients were able to walk with partial weight-bearing on crutches. All 43 patients were followed up for more than 6 months,with a follow-up period of (33.3±7.3) weeks (range:24 to 42 weeks).The external fixation frame was removed after the fracture healed.The external frame was removed at 20(3)weeks (range:18 to 25 weeks) postoperatively. Up to the final follow up, no secondary fracture occurred in any of them.The Johner-Wruhs score of the affected limb at the last follow-up was excellent in 39 cases and good in 4 cases. Conclusion: The digital six-axis external fixator based on CT data for tibiofibular fractures has the advantages of precise reduction,firm fixation,simple operation,rapid fracture healing,and minimal trauma, which is a minimally invasive method for treating tibiofibular fractures,especially suitable for patients with poor skin and soft tissue conditions such as open injuries.

[Analysis of differences and influencing factors of liver injury associated with different strains of 2019-nCoV infection].

Objective: To analyze whether there are differences and related influencing factors in liver injury associated with different strains of 2019-nCoV/SARS-CoV-2 infection. Methods: Data of epidemiology, clinical symptoms, laboratory tests, and treatment outcomes of patients with COVID-19 infection confirmed with Alpha and Delta virus strain in Zhejiang Province were retrospectively collected. Statistical analysis was performed using independent samples t-test or Mann-Whitney U test, χ2 test or Fisher's exact test, and logistic regression analysis. Results: A total of 788 and 381 cases with Alpha and Delta virus strain were included. Vaccination ratio was 0% in Alpha and 85.30% in Delta group (P<0.001), The proportion of patients with fever (80.71% vs. 40.94%, P<0.001) was significantly higher in Alpha than Delta strain group. The proportion of critical ill patients was significantly higher in Delta group (9.90% vs. 1.57%, respectively, P<0.001). The virus negative conversion time was significantly longer in Delta than Alpha group (22 d vs. 11 d, P<0.001), but the incidence of liver injury was significantly higher in Alpha than Delta group (20.05% vs. 13.91%, P=0.011). Univariate analysis showed that Alpha virus strain infection, male sex, body mass index, chronic liver disease, fever, diarrhea, shortness of breath, severe/critical illness, elevated creatine kinase (CK), elevated international normalized ratio (INR) and an elevated neutrophil/lymphocyte ratio was significantly associated with an increased risk of liver injury occurrence, and in patients with pharyngeal pain the risk of liver injury occurrence was significantly reduced. Multivariate analysis showed that shortness of breath [OR, 2.667 (CI: 1.389-5.122); P=0.003], increased CK [OR, 2.544 (CI: 1.414-4.576); P=0.002] and increased INR [OR, 1.721] (CI: 1.074-2.758); P=0.024] was significantly associated with an increased risk of liver injury occurrence, and in patients with pharyngeal pain the risk of liver injury occurrence was significantly reduced [OR, 0.424 (CI: 0.254-0.709); P=0.001]. Conclusion: Although the virulence of the Delta is stronger than Alpha strain, most patients infected with Delta strain vaccinated against COVID-19 in Zhejiang province had milder clinical symptoms and a lower incidence and degree of liver injury. Notably, the infection risk even remains after vaccination; however, symptoms and the incidence of severe and critical illness can be significantly reduced.

[Association of cadmium internal exposure with chronic kidney disease in Chinese adults].

Objective: To analyze the association of the cadmium internal exposure with chronic kidney disease (CKD) in Chinese adults aged 18 and older. Methods: A total of 9 821 adults aged 18-79 from the China National Human Biomonitoring (CNHBM) from 2017 to 2018 were included. Blood and urine cadmium exposure levels were measured by inductively coupled plasma mass spectrometry (ICP-MS), and urine cadmium levels were adjusted with urine creatinine; CKD were defined by estimated glomerular filtration (eGFR) using the chronic kidney disease epidemiology collaboration (CKD-EPI). Weights were considered due to complex sampling process for in statistical analysis. Logistic regression is used to analyze the association of blood cadmium, urine cadmium, and urine cadmium adjusted with creatinine exposure levels with CKD, and restricted cube spline (RCS) was used to assess the exposure-response curve of blood cadmium, urine cadmium and urine cadmium adjusted with creatinine with CKD. Results: The weighted age was 44.75 and males accounted for 61.1%. The prevalence rate of CKD was 12.7%. The geometric mean values of blood cadmium, urine cadmium, and urine cadmium adjusted with creatinine were 0.96 µg/L, 0.61 µg/L, and 0.58 µg/g. After adjusting for confounding factors, the weighted logistic regression showed that the lowest quintile (Q1) was compared with the odds ratio (OR) of the highest quintile (Q5) of blood cadmium, urine cadmium, and urine cadmium adjusted with creatinine and the 95% confidence interval (CI) was 1.80 (1.02-3.20), 1.77 (0.94-3.31) and 1.94 (1.11-3.37) respectively. In the restricted cubic spline regression model, non-linear association of blood cadmium, urine cadmium, and urine cadmium adjusted with creatinine with CKD were observed after adjusting for related confounding factors (P<0.001, 0.018, 0.031 respectively). The risk of CKD increased with the increment of cadmium exposure without risk threshold, and the exposure response curve was steeper at low cadmium exposure. Conclusions: Among Chinese adults aged 18 and older, cadmium exposure is positively associated with the risk of chronic kidney disease.

Automated Radiographic Evaluation of Adenoid Hypertrophy Based on VGG-Lite.

Adenoid hypertrophy is a pathological hyperplasia of the adenoids, which may cause snoring and apnea, as well as impede breathing during sleep. The lateral cephalogram is commonly used by dentists to screen for adenoid hypertrophy, but it is tedious and time-consuming to measure the ratio of adenoid width to nasopharyngeal width for adenoid assessment. The purpose of this study was to develop a screening tool to automatically evaluate adenoid hypertrophy from lateral cephalograms using deep learning. We proposed the deep learning model VGG-Lite, using the largest data set (1,023 X-ray images) yet described to support the automatic detection of adenoid hypertrophy. We demonstrated that our model was able to automatically evaluate adenoid hypertrophy with a sensitivity of 0.898, a specificity of 0.882, positive predictive value of 0.880, negative predictive value of 0.900, and F1 score of 0.889. The comparison of model-only and expert-only detection performance showed that the fully automatic method (0.07 min) was about 522 times faster than the human expert (36.6 min). Comparison of human experts with or without deep learning assistance showed that model-assisted human experts spent an average of 23.3 min to evaluate adenoid hypertrophy using 100 radiographs, compared to an average of 36.6 min using an entirely manual procedure. We therefore concluded that deep learning could improve the accuracy, speed, and efficiency of evaluating adenoid hypertrophy from lateral cephalograms.

Laser vibrational excitation of radicals to prevent crystallinity degradation caused by boron doping in diamond.

Pursuing high-level doping without deteriorating crystallinity is prohibitively difficult but scientifically crucial to unleashing the hidden power of materials. This study demonstrates an effective route for maintaining lattice integrity during the combustion chemical vapor deposition of highly conductive boron-doped diamonds (BDDs) through laser vibrational excitation of a growth-critical radical, boron dihydride (BH2). The improved diamond crystallinity is attributed to a laser-enabled, thermal nonequilibrium suppression of the relative abundance of boron hydrides (BH), whose excessive presence induces boron segregation and disturbs the crystallization. The BDDs show a boron concentration of 4.3 × 1021 cm-3, a film resistivity of 28.1 milliohm·cm, and hole mobility of 55.6 cm2 V-1 s-1, outperforming a commercial BDD. The highly conductive and crystalline BDDs exhibit enhanced efficiency in sensing glucose, confirming the advantages of laser excitation in producing high-performance BDD sensors. Regaining crystallinity with laser excitation in doping process could remove the long-standing bottlenecks in semiconductor industry.

[Effects and mechanism of Lactococcus lactis thermo-sensitive hydrogel on the wound healing of full-thickness skin defects in diabetic mice].

Objective: To explore the effects and mechanism of Lactococcus lactis (L. lactis) thermo-sensitive hydrogel on the wound healing of full-thickness skin defects in diabetic mice. Methods: (1) According to the volume ratio of bacteria to medium of 1∶100, about 5×10(8) colony forming units/mL (the same concentration below) L. lactis was cultured in M17GS liquid medium. The growth conditions were observed at 0 (immediately), 2, 4, 6, 8, 10, and 12 h of culture with a microplate reader. In addition, another colony of the bacteria was taken and cultured under the same condition mentioned above. The culture medium was collected at the same time points as mentioned above, and the supernatant of bacterial culture was isolated. With the supernatant, the pH value was measured with a desktop pH meter, and the concentration of L-lactic acid at 0 (immediately), 2, 4, 8, and 12 h of culture was determined by the L-lactic acid detection and analysis kit (n=3). (2) To prepare a simple thermo-sensitive hydrogel, the poloxamer thermo-sensitive polymer and M17GS liquid medium were mixed thoroughly according to the mass-volume ratio of 0.2 g∶1 mL. L. lactis was added to the simple thermo-sensitive hydrogel according to the volume ratio of bacteria to hydrogel of 1∶100, and the L. lactis thermo-sensitive hydrogel was prepared after thorough mixing. Afterwards, the morphology of L. lactis thermo-sensitive hydrogel was observed after 4 ℃, 37 ℃ incubation and again at 4 ℃ incubation after gelation. The storage modulus and loss modulus of the L. lactis thermo-sensitive hydrogel at 10-40 ℃ were measured by rheometer, and the gel forming temperature was observed. After freeze-drying the L. lactis thermo-sensitive hydrogel, the surface and the morphological structure of L. lactis in the hydrogel were observed by scanning electron microscope. (3) Mouse macrophages Raw264.7 cells were M1-type polarization stimulated by culturing with lipopolysaccharide and interferon γ in the final mass concentration of 100 and 10 ng/mL respectively for 24 h. The cells were divided into blank control group (without other treatment), L. lactis thermo-sensitive hydrogel group, and lactic acid group. L. lactis thermo-sensitive hydrogel in the volume of 1 mL was added to the cells of L. lactis thermo-sensitive hydrogel group, while lactic acid with the final molarity of 30 mmol/L was added to the cells in lactic acid group. After being cultured at 37 ℃ for 24 h, mRNA expressions of the markers arginase 1 and CD206 of M2-type macrophages were detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR) (n=3), and the immunofluorescence method was used to detect the protein localization and expression of arginase 1 and CD206. (4) Fifteen female BALB/c mice aged 8-10 weeks were induced into diabetic mouse models by the method of streptozotocin combined with high-sugar and high-fat diet, and a full-thickness wound with the diameter of 6 mm was made on the back of each mouse. The mice were divided into blank control group (without other treatment), thermo-sensitive hydrogel alone group, and L. lactis thermo-sensitive hydrogel group according to the random number table, with 5 mice in each group. The mice in the hydrogel treatment two groups were dripped with 200 µL corresponding hydrogel to the wound surface immediately after injury, and the hydrogel was replaced every day. After treatment for 0 (immediately), 3, 6, 9, and 12 days in the hydrogel treatment two groups, wound healing was observed, and wound area was measured. After 12 days of treatment, the wound tissue was taken to observe the thickness of granulation tissue by hematoxylin-eosin staining and CD206 and the marker of M1-type macrophages of inducible nitric oxide synthase (iNOS) positive cells by immunofluorescence method. The mice in blank control group were observed at the same time points as mentioned above. (5) Nine female BALB/c mice aged 8-10 weeks were induced into diabetic mouse models by the same method of experiment (4). Then, they were divided into normal skin group (without other treatment), wound alone group, and L. lactis thermo-sensitive hydrogel group according to the random number table, with 3 mice in each group. Mice in wound alone group and L. lactis thermo-sensitive hydrogel group were prepared with full-thickness skin defect wounds according to the method of experiment (4). Mice in the former group was left untreated after injury, and in the latter group, 200 µL L. lactis thermo-sensitive hydrogel was dripped onto the wound surface immediately after injury. After treatment for 1 day in hydrogel treatment group, the wound tissue of mice was taken, and the mRNA expressions of interleukin 1ß (IL-1ß), tumor necrosis factor α (TNF-α), and nuclear factor κB were detected by real-time fluorescence quantitative RT-PCR; after the eyeball blood was collected, the leukocyte count, lymphocyte count, and monocyte count in peripheral blood were measured by an automatic blood cell analyzer, and the serum L-lactic acid concentration was measured by the L-lactic acid detection and analysis kit. At the same time point mentioned above, normal skin tissue was taken from the corresponding parts of mice in normal skin group, wound tissue was taken from mice in wound alone group, and blood was taken from mice of the two groups for corresponding detection. Data were statistically analyzed with one-way analysis of variance, analysis of variance for repeated measurement, Tukey, and Dunnett test. Results: (1) The growth of L. lactis reached the plateau in about 6 h of culture. In the culture supernatant of L. lactis, the pH value gradually decreased, reaching the nadir about 4.9 after 8 h of culture, and the L-lactic acid concentration gradually increased, which peaked about 70 mmol/L after 8 h of culture. (2) The L. lactis thermo-sensitive hydrogel was a liquid at 4 ℃, and a solid gel at 37 ℃. After gelation, it became a liquid again after incubating at 4 ℃. The gel forming temperature was about 25 ℃. The storage modulus was about 3 000 Pa, and the loss modulus was about 1 000 Pa after gelation. Under the scanning electron microscope, the L. lactis thermo-sensitive hydrogel showed a loose three-dimensional porous structure, and the L. lactis had an ellipsoidal shape being wrapped inside the hydrogel. (3) After 24 h of culture, compared with those in blank control group, the expression of arginase 1 increased significantly (q=11.620, 15.250, P<0.01), the expression of CD206 mRNA increased significantly (q=16.770, 19.030, P<0.01), and the expression of CD206 protein located in the cell membrane and arginase 1 protein located in the cytoplasm increased significantly in the macrophages of L. lactis thermo-sensitive hydrogel group and lactic acid group. The expressions of arginase 1 and CD206 mRNA in the macrophages between lactic acid group and L. lactis thermo-sensitive hydrogel group were similar (q=3.629, 2.259, P>0.05). (4) After 3-12 days of treatment, compared with those in blank control group and thermo-sensitive hydrogel alone group, the wound of mice in L. lactis thermo-sensitive hydrogel group healed faster, the wound area was significantly reduced, and the inflammation of the wound edge tissue was reduced. After treatment of 3, 6, 9, 12 days, the wound areas of mice in L. lactis thermo-sensitive hydrogel group were (25.8±5.9), (21.2±4.6), (16.0±2.4), (8.4±2.4) mm(2) respectively, which were significantly smaller than (31.8±5.3), (28.0±3.4), (22.6±3.7), (17.0±1.0) mm(2) in blank control group (q=3.506, 3.973, 3.856, 5.025, P<0.05 or P<0.01). After treatment of 3 and 6 days, the wound areas of mice in L. lactis thermo-sensitive hydrogel group were significantly smaller than those in thermo-sensitive hydrogel alone group (q=3.739, 3.739, P<0.05). After 12 days of treatment, compared with those in blank control group and thermo-sensitive hydrogel alone group, the wound granulation tissue of mice in L. lactis thermo-sensitive hydrogel group was thicker, with significantly reduced iNOS positive cells and increased CD206 positive cells in wound tissue. (5) After 1 day of treatment, the mRNA expressions of IL-1ß, TNF-α, and nuclear factor κB in the wound tissue of mice in wound alone group were significantly higher than those of normal skin tissue of mice in normal skin group (q=9.253, 4.819, 6.020, P<0.01) but similar to those in L. lactis thermo-sensitive hydrogel group (q=2.850, 2.735, 2.556, P>0.05). The peripheral blood leukocyte count, lymphocyte count, and monocyte count of mice in wound alone group were significantly higher than those in normal skin group (q=3.523, 5.373, 5.279, P<0.05 or P<0.01) but similar to those in L. lactis thermo-sensitive hydrogel group (q=0.621, 1.240, 1.293, P>0.05). The serum L-lactic acid concentration of mice in the three groups remained within the normal range and the overall comparison among them was not statistically significant (F=4.095, P>0.05). Conclusions: The L. lactis thermo-sensitive hydrogel was safe to use locally on the wounds of diabetic mice with full-thickness skin defects. It can produce and deliver lactic acid in situ, promote the polarization of macrophages from M1 to M2, reshape the wound healing microenvironment, and promote efficient wound healing.

[Effects and mechanism of copper oxide nanozymes on wound healing of full-thickness skin defects in diabetic mice].

Objective: To investigate the effects and mechanism of copper oxide nanozymes on wound healing of full-thickness skin defects in diabetic mice. Methods: (1) Copper oxide nanozymes were synthesized through the reaction of copper chloride and L-ascorbic acid. Transmission electron microscope was used for observing the particle size and morphology of copper oxide nanozymes, and dynamic light scattering particle size analyzers and Zeta potentiometer were used to analyze the hydrated particle size and surface potential of copper oxide nanozymes, respectively. (2) The hydrogen peroxide detection kit, superoxide anion determination kit, and 3, 3', 5, 5'-tetramethylbenzidine were used to test the hydrogen peroxide, superoxide anion, and hydroxyl radicals scavenging ability of 150 ng/mL copper oxide nanozymes, respectively, and the scavenging proportions of hydrogen peroxide, superoxide anion, and hydroxyl radicals were calculated. The sample numbers were all 3. (3) Mouse fibroblast cell line 3T3 cells were divided into blank control group, simple hydrogen peroxide group, and hydrogen peroxide+ copper oxide group according to the random number table (the same grouping method below), with 3 wells in each group. Cells in hydrogen peroxide+ copper oxide group were pre-treated with copper oxide nanozymes in final mass concentration of 25 ng/mL for 30 minutes, and then hydrogen peroxide in final molarity of 250 µmol/L was added into simple hydrogen peroxide group and hydrogen peroxide+ copper oxide group. Cells in blank control group were routinely cultured. After 24 hours of culture, 2', 7'-dichlorodihydrofluorescein diacetate fluorescence probe was used to detect the level of reactive oxygen species (indicated by green fluorescence intensity) in cells and cell counting kit-8 assay was performed to detect and calculate the cell survival rate. (4) Ten male BALB/c mice aged 6-8 weeks (the same gender and age below) were divided into phosphate buffer saline (PBS) group and copper oxide group, with 5 mice in each group. The mice in the copper oxide group were injected with 800 ng/kg copper oxide nanozyme at a concentration of 200 ng/mL via the caudal vein, and the mice in PBS group were treated with the same volume of PBS. The mice in the two groups were treated once a day for seven consecutive days. On the eighth day, 5 mice from each group were conducted and blood samples were taken for analysis of blood panel and serum biochemistry, and then the heart, liver, spleen, lung, and kidney were harvested for histopathological observation by hematoxylin-eosin (HE) staining after the mice were sacrificed. (5) Twenty mice were divided into PBS group and copper oxide group, with 10 mice in each group. Diabetes was induced by streptozotocin and high-sugar and high-fat diet and a full-thickness skin defect wound with diameter of 6 mm was reproduced on the back of each diabetic mouse. Immediately after injury, 20 µL PBS and 20 µL copper oxide nanozymes at the concentration of 200 ng/mL were added respectively to the wounds of mice in PBS group and copper oxide group, with the treatment being continued for twelve consecutive days. Three mice were selected from each group, and the wound healing was observed on post injury day (PID) 0 (immediately), 3, 6, 9, and 12 and the un-healed area was calculated. On PID 6, three mice from each group that were not for wound observation were sacrificed, and the content of interleukin 1ß (IL-1ß), tumor necrosis factor-α (TNF-α), and IL-6 in the wound tissue were determined by enzyme-linked immunosorbent assay. On PID 12, the rest 7 mice in each group were sacrificed for observation of the length of regenerated epidermis in wound tissue by HE staining, and the level of reactive oxygen species (indicated as red fluorescence intensity) in wound tissue by dihydroethidium staining. Data were statistically analyzed with one-way analysis of variance, analysis of variance for repeated measurement, independent sample t test, and Bonferroni test. Results: (1) The prepared copper oxide nanozymes were uniform in size with an average diameter of 3.5-4.0 nm in dry state, the hydrated particle size of 4.5 nm, and the surface potential of (-9.8±0.3) mV. By comprehensive judgment, copper oxide nanozymes had been successfully prepared. (2) After being treated with copper oxide nanozyme for 2 hours, 10 minutes, and 5 minutes, respectively, the scavenging proportions of hydrogen peroxide, superoxide anion, and hydroxyl radicals were (77±5)%, (45±5)%, and (84±4)%, respectively. (3) After 24 hours of culture, the cells in simple hydrogen peroxide group showed a significantly increased level of reactive oxygen species with abnormal morphology and decrease in cell number, while the cells in hydrogen peroxide+ copper oxide group showed a remarkably decreased level of reactive oxygen species with normal morphology similar to that of blank control group. The cell survival rate in simple hydrogen peroxide group was obviously reduced compared with the rates in blank control group and hydrogen peroxide+ copper oxide group (P<0.01), while there was no significant difference in cell survival rate between hydrogen peroxide+ copper oxide group and blank control group. (4) After 7 days of injection, there were no obvious differences in liver and kidney function indexes and blood panel indexes between mice in PBS group and copper oxide group. No necrosis, hyperaemia or hemorrhage in heart, liver, spleen, lung, or kidney was observed in mice in copper oxide group, which was similar to that in PBS group. (5) Compared with that of PBS group, wounds of mice in copper oxide group showed an accelerated healing trend with less redness. On PID 6, 9, and 12, the areas of un-healed wound of mice in copper oxide group (28.8±1.9), (17.6±3.8), and (10.4±1.8) mm(2), respectively, significantly lower than (38.0±4.3), (30.2±3.0), and (24.2±3.0) mm(2) in PBS group (t=3.706, 5.075, 5.558, P<0.01). On PID 6, the content of IL-1ß, TNF-α, and IL-6 in wounds of mice in copper oxide group were significantly lower than that in PBS group (t=6.115, 11.762, 11.725, P<0.01). On PID 12, the length of regenerated epidermis in wounds of mice in copper oxide group was obviously longer than that in PBS group, the level of reactive oxygen species in wounds of mice in copper oxide group was obviously lower than that in PBS group. Conclusions: Copper oxide nanozyme not only has good biocompatibility, but also has efficient reactive oxygen species scavenging activity. It can eliminate the over-expressed reactive oxygen species in the full-thickness defect wounds of diabetic mice, reduce oxidative stress and inflammation, thus promoting wound repair.

Circ-ABCB10 acts as an oncogene in glioma cells via regulation of the miR-620/FABP5 axis.

OBJECTIVE: This study aims to investigate the biological function of circular RNA ABCB10 (circ-ABCB10) in regulating the progression of glioma and to study the possible underlying mechanisms. PATIENTS AND METHODS: The expression levels of circ-ABCB10, miR-620 and FABP5 mRNA in glioma tissues, normal surrounding tissues and glioma cell lines were measured by Real-time PCR (RT-PCR). Circ-ABCB10 was silenced by siRNA in glioma cell lines (U87, T98G). The proliferation, migration and invasion of glioma cells were measured by MTT, wound healing and transwell assays, respectively. The relationship between circ-ABCB10, miR-620 and FABP5 was tested by Dual-Luciferase assay. The expression of proteins was measured by Western blot. The cell cycle distribution and apoptosis were measured by flow cytometry. RESULTS: The expression levels of circ-ABCB10 and FABP5 in glioma tissues and cells were significantly higher than those in their normal counterparts. Moreover, the expression of miR-620 was lower in glioma tissues. Silencing of circ-ABCB10 in glioma cells significantly inhibited the proliferation, migration and invasion of glioma cells. Moreover, downregulation of circ-ABCB10 induced cell cycle arrest and apoptosis in glioma cells. Furthermore, inhibition of miR-620 showed the opposite effects to silencing circ-ABCB10 on glioma cells. Dual-Luciferase reporter assays demonstrated that circ-ABCB10 could bind to miR-620 and that FABP5 was a direct target of miR-620. Western blot results showed that circ-ABCB10 could stabilize the expression of FABP5, while miR-620 decreased the expression of FABP5. Furthermore, overexpression of FABP5 abrogated the silencing effects of circ-ABCB10 in glioma cells. CONCLUSIONS: These data suggest that circ-ABCB10 affects glioma progression by regulating the miR-620/FABP5 axis, and circ-ABCB10 might be used as a potential target for the treatment of glioma.

Isotopic determination with molecular emission using laser-induced breakdown spectroscopy and laser-induced radical fluorescence.

Molecular emission can be used for isotopic analysis in laser-induced breakdown spectroscopy (LIBS) due to its large isotopic shift. However, spectral weakness and interference have become the main flaws in molecular isotopic analysis, causing deterioration of quantitative accuracy and sensitivity. Here, to overcome these problems, laser-induced radical fluorescence (LIRF) was applied to enhance the molecular spectra and eliminate the spectral interference. The root mean square errors of cross validation (RMSECVs) of boron and carbon isotopes (11BO, 10BO, 12CN, and 13CN) improved to 2.632, 5.721, 5.990, and 1.543 at.%, as compared with 16.96, 35.79, 57.10, and 13.89 at.%, respectively, obtained in the case without LIRF. The limits of detection (LoDs) of 11BO, 10BO, 12CN, and 13CN were 0.9858, 0.8470, 1.606, and 1.193 at.%, respectively. This work demonstrates the feasibility of LIBS-LIRF to achieve isotopic determination with high accuracy and sensitivity.

One-point and multi-line calibration method in laser-induced breakdown spectroscopy.

The calibration-free laser-induced breakdown spectroscopy (CF-LIBS) and its variations are low cost, short time consumption, and high adaptability. However, seeking a more flexible and simple quantitative analysis method remains a challenge. A one-point and multi-line calibration (OP-MLC) was presented as a simple quantitative analysis method of LIBS. The results showed that OP-MLC-LIBS method can achieve quantitative analysis using only one standard sample, and the average relative errors (AREs) are 9, 22, 21 and 36% for Mn, Cr, Ni and Ti elements in six tested low-alloy steel samples, respectively. The method requires neither a large number of standard samples nor complicated calculations, which provides a flexible and low-cost quantitative analysis approach for development and application of LIBS.

[A new method of measuring leg length discrepancy on radiograph in patients undergoing total hip arthroplasty].

Objective: To investigate the reliability of the distance between the tip of the greater trochanter and inter-teardrop line (GT-IT) in evaluating the leg length discrepancy (LLD) in patients underwent total hip arthroplasty (THA). Methods: Patients who underwent THA in Xi'an Honghui Hospital from August 2015 to February 2016 were enrolled in this study.The patients were measured for bilateral hips anterior-posterior (AP) radiograph preoperatively and postoperatively.Four distances measured, included: GT-IT, the tip of lesser trochanter and bi-ischial line (LT-BI); LT-IT and the anterior superior iliac spine and the medial malleolus (ASIS-MM). Magnification factor was considered when calculating absolute values.Intraclass correlation coefficient (ICC) was used to detect the reliability of the measurement data.Single factor analysis and paired t test were performed to compare data among the methods. Results: The ICC values of the four groups were greater than 0.80, which showed excellent agreement in the measurements.Single factor analysis of variance showed there were no statistically significant differences in the LLDs of the four groups preoperatively and postoperatively (F=0.914, 0.886, both P>0.05). There was no significant differences in preoperative and postoperative LLD between group GT-IT and group ASIS-MM, LT-BI or LT-IT(t=-1.544-1.114, all P>0.05). The LLDs were comparable between group LT-BI, ASIS-MM and LT-IT both preoperatively and postoperatively (t=1.577, 0.976, 1.344, -0.087, all P>0.05). And the LLD in group LT-IT and ASIS-MM were equivalent preoperatively and postoperatively (t=0.130, 1.063, both P>0.05). Bland-Altman plot illustrated high level of agreements between the four methods. Conclusion: Great reliability can be obtained with the GT-IT in evaluating the LLD in patients undergoing THA.

[Effect of workplace bullying on posttraumatic stress disorder in nursing staff].

Objective: To investigate the relationship between workplace bullying and posttraumatic stress disorder (PTSD) in nursing staff, and to analyze the role of psychological capital between workplace bullying and PTSD. Methods: From December 2014 to June 2015, convenience sampling was used to collect 496 nurses from 5 grade A tertiary hospitals in a province of China. Their workplace bullying, psychological capital, and PTSD status were assessed using the Negative Acts Questionnaire, Psychological Capital Questionnaire, and Posttraumatic Stress Disorder Self-Rating Scale, respectively. The correlation between variables was analyzed using a structural equation model. Results: Among these nurses, the scores of negative acts, psychological capital, and PTSD were 37.15±12.83, 78.81±16.54, and 34.56±12.52, respectively. The score on each dimension of negative acts was positively correlated with that on each dimension of PTSD (P<0.01) ; the score on each dimension of psychological capital was negatively correlated with that on each dimension of PTSD and negative acts (P<0.01). Negative acts had a positive predictive effect on PTSD (ß=0.539, P<0.01) , which was reduced after inclusion of psychological capital (ß=0.513, P<0.01). The path coefficient was 0.62 for the effect of negative acts on PTSD, -0.18 for the effect of negative acts on psychological capital, and -0.11 for the effect of psychological capital on PTSD (P<0.05) . Conclusion: Workplace bullying is a predictive factor for PTSD, and psychological capital plays a mediating role between workplace bullying and PTSD. The manager should reduce workplace bullying to improve the psychological capital in nursing staff and to prevent and reduce PTSD.

Determination of boron with molecular emission using laser-induced breakdown spectroscopy combined with laser-induced radical fluorescence.

Boron is an essential element for industry, but it is hard to accurately and rapidly determine high boron content with conventional laser-induced breakdown spectroscopy (LIBS), due to the matrix and self-absorption effect. Using molecular emission is an alternative method for boron content analysis, but its weak spectra are major challenges. Here, boron monoxide (BO) radicals were used to establish calibration assisted by LIBS and laser-induced radical fluorescence (LIBS-LIRF). Two types of BO radical excitations, vibrational ground state excitation (LIRFG) and vibrational excited state excitation (LIRFE), were compared. The results showed that LIRFG achieved better sensitivity with a limit of detection of 0.0993 wt.%, while the LIRFE was more accurate with a root mean square error of cross validation of 0.2514 wt.%. In conclusion, this work provided a potential approach for molecular emission analysis with LIBS-LIRF.