[Role of pyroptosis pathway related molecules in acute lung injury induced by gas explosion in rats]

Objective: To explore the role and significance of pyroptosis in gas explosion-induced acute lung injury (ALI) in rats. Methods: In February 2018, 126 SPF male SD rats were selected and randomly divided into blank control group (18 rats) and experimental group (40 m, 80 m, 120 m, 160 m, 200 m and 240 m, 18 per group) . The experimental group carried out gas explosion in the roadway to build the ALI model, the control group did not carry out gas explosion, and other conditions were consistent with the experimental group. Respiratory function indexes such as respiratory frequency (f) , tidal volume (TV) , minute ventilation (MV) and airway stenosis index (Penh) were measured 24 hours after the explosion. 5 rats in each group were sacrificed after anesthesia, Hematoxylin-Eosin (HE) staining was used to observe the pathological morphology of lung tissue. Immunohistochemistry was used to detect the content of Caspase-1. Western blotting was used to detect the content of cell pyroptosis including nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) , Caspase-1, interleukin-1β (IL-1β) and interleukin-18 (IL-18) in lung tissue related protein expression. Results: The f and MV of rats in the experimental group were higher than those in the control group (P<0.05) . Except for the 40 m and 80 m groups, the TV of rats in the other experimental groups were higher than those in the control group (P<0.05) . Except for the 40 m group, the Penh of rats in the experimental groups were lower than those in the control group (P<0.05) . HE staining showed that the lung tissue of the experimental groups at different distance points showed obvious edema of the pulmonary interstitium and alveoli, a large number of red blood cells and inflammatory cells exuded in the alveolar space, thickening of the pulmonary interstitium, and increased lung injury score (P<0.05) . The results of immunohistochemistry showed that the positive expression of Caspase-1 in each experimental group was higher than that in the control group (P<0.05) . Western blotting results showed that the expression of pyroptosis-related proteins in each experimental group was higher than that in the control group (P<0.05) . Conclusion: Pyroptosis is involved in the pathophysiological process of gas explosion-induced ALI in rats.

[Expression of LIAS and NRF2 in PBMCs from patients with silicosis and their correlation with silicosis]

Objective: To investigate the expression of lipoic acid synthase gene (LIAS) and nuclear factor-erythroid 2-related factor 2 gene (NRF2) in peripheral blood mononuclear cells (PBMCs) from patients with silicosis and their correlation with silicosis. Methods: A total of 45 healthy controls and 107 patients with silicosis were randomly selected in this study in May 2019. PBMCs were isolated from peripheral blood and NRF2 protein expression was detected by immunofluorescence. The mRNA levels of LIAS and NRF2 in PBMCs were determined by real-time PCR. The dose-response relationship beween LIAS and NRF2 mRNA expression levels and their association with silicosis were analyzed by restricted cubic spline (RCS) and logistic regression. Results: Compared with the control group, the number of monocytes in the case group was significantly increased, and the forced expiratory volume in the first second (FEV(1.0)) decreased, the difference was statistically significant (P<0.05) . The positive expression rate of NRF2 in PBMCs of silicosis patients in stage Ⅰ group was significantly higher than that in the control group, and the positive expression rate of NRF2 in silicosis patients in stageⅡ and Ⅲ groups was lower than that in silicosis patients in control group and stage Ⅰ group (P<0.01) . Results of RCS showed that there was a linear dose-response relationship between LIAS and NRF2 mRNA expression (overall correlation test, χ(2)=213.710, P<0.01; non-linear test, χ(2)=1.340, P=0.511) . There was a positive correlation between mRNA expression of LIAS and that of NRF2 (r=0.651, P<0.01) . The results of multivariate analysis showed that LIAS and NRF2 were increased the risk of incidence in silicosis patients with stageⅠ (OR=11.184, 4.332, P<0.05) and NRF2 was the protective factor in silicosis patients with stage Ⅱ and Ⅲ (OR=0.225, 0.208, P<0.05) after adjusting for potential confounding factors including age, education level, BMI and smoking. Conclusion: There is a linear dose-response relationship between the expression of LIAS and NRF2 mRNA in PBMCs of silicosis patients, LIAS and NRF2 are involved in the pathogenesis of silicosis.

[Study on serum metabolomics of combined injury induced by gas explosion in rats]

Objective: To analyze the changes of serum metabolomics in rats with combined injuries caused by gas explosion and explore its possible mechanism. Methods: In April 2018, the large coal mine gas explosion test roadway and explosion test system were used to simulate the gas explosion experiment. All 32 SD rats were randomly divided into four groups, control group (not involved in the explosion) , close range (40 m) group, medium range (160 m) group and long range (240 m) group, 8 in each group. The respiratory function at 2 hours and the neural behavior at 48 hours were detected after the explosion. The rats were anesthetized and sacrificed after 48 hours, and the serum, lung, liver and other tissues of the rats were isolated and histopathological changes of lung and liver tissues were observed by HE staining. Serum samples were detected by liquid chromatography-high resolution mass spectrometry (UPLC-Orbitrap Elite/MS) , and metabolic spectrum differences between groups were evaluated by principal component analysis. Differential metabolites were screened and identified, and metabolic pathways were analyzed. Results: Compared with control group, respiratory function indexes (respiratory frequency, minute ventilation, peak inspiratory flow rate, peak expiratory flow rate and 1/2 tidal volume expiratory flow) of rats in different explosion groups were significantly decreased (P<0.05) , but respiration pause, inspiratory time and 2/3 tidal volume required time were significantly increased (P<0.05) in 2 hours after the explosion. However, the residence times of the neurobehavioral indicators of the 40 m group and 160 m group were significantly increased (P<0.05) , and the movement distances were significantly decreased (P<0.05) in 48 hours after the explosion. HE staining results showed that the lung and liver tissues of the rats in the gas explosion group structurally damaged, and the cells were disordered, with inflammatory cell infiltration, bleeding and edema. Metabonomics analysis showed that there were significant differences in metabolic profiles between groups. A total of 18 differential metabolites were identified in serum samples, including aconitum acid, citric acid, niacinamide and pyruvate, which involved in 12 major metabolic pathways, including the glutamic acid and glutamine metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, glyoxylic acid and dicarboxylic acid metabolism, phenylalanine metabolism, nicotinic acid and nicotinamide metabolism, citric acid cycle (TCA cycle) . Conclusion: Gas explosion can cause multi-organ system damage in rats, the mechanism of which may be related to the biosynthesis of alanine, tyrosine and tryptophan, metabolism of niacin and niacinamide, metabolism of acetaldehyde and dicarboxylic acid, and TCA cycle, etc.

[Changes and significance of autophagy in rat lung injury induced by gas explosion]

Objective: To explore the changes and significance of autophagy in acute lung injury (ALI) induced by gas explosion in rats. Methods: In February 2018, the gas explosion in underground coal mine was simulated by large tunnel explosion experiment system, SD rats were randomly divided into control group and 6 distance groups (40 m, 80 m, 120 m, 160 m, 200 m, 240 m) with 18 rats in each group. The respiratory function of rats 24 h before and after explosion was detected. Post-explosion rats were anesthetized and sacrificed, histopathological changes of lung were observed by HE staining. Immunohistochemistry was performed to detect the in situ expression of autophagy marker protein microtubule-associated protein 1 light chain 3 (LC3B) . The expression levels of autophagy related gene 12 (Atg12) , LC3B, P62, lysosomal associated membrane protein 2 (Lamp2) , B-cell lymphoma/leukemia-2 (Bcl-2) and Bcl2 interaction protein (Beclin-1) were detected by Western blot. Results: After gas explosion, the rats in 80 m distance point group had the hightest mortality (n=13, 72.22%) and the most severe lung injury degree, and the histopathological scores was (4.00±0.00) point. After gas explosion, the minute ventilation volume (MVb) , maximum inspiratory flow rate (PIFb) and maximum expiratory flow rate (PEFb) of rats were lower than before the gas explosion (P<0.05) . The respiratory frequency of rats in 80 m, 200 m, and 240 m distance point groups were significantly higher than that in the control group (P<0.05) . The expression levels of LC3B in 40 m, 80 m, 120 m, 160 m, and 200 m distance point groups were higher than that in the control group (P<0.05) . The relative expression levels of Atg12 and LC3BⅡ/Ⅰ in lung tissues of rats in different distance point groups were higher than those in the control group (P<0.05) . The relative expression levels of Beclin1 in 40 m, 80 m, 120 m, and 160 m distance point groups were significantly higher than that in the control group (P<0.05) . The relative expression levels of P62 in 80 m, 160 m and 200 m distance point groups were lower than that in the control group (P<0.05) . The relative expression levels of Lamp2 and Bcl-2 in lung tissues of rats in all distance groups except 240 m distance group were lower than those in the control group (P<0.05) . Conclusion: Gas explosion could induce increased autophagy in lung tissues of ALI rats. Autophagy-related signaling pathway could be involved in the pathophysiological process of ALI in rats caused by gas explosion, then the autophagy and the severity of the lesion showed a significant positive correlation.

[Influences of gas explosion on acute blast lung injury and time phase changes of pulmonary function in rats under real roadway environment]

Objective: The aims of this study were to investigate the effect of gas explosion on rats and to explore the pulmonary function alterations associated with gas explosion-induced acute blast lung injury (ABLI) in real roadway environment. Methods: In April 2018, the large coal mine gas explosion test roadway and explosion test system were used to simulate the real gas explosion roadway environment, fixed the cage and set the explosion parameters. 72 SD rats, male, SPF grade, were randomly divided into nine groups by completely random grouping method according to their body weight: control group, close range group (160 m) , and long range group (240 m) . In each group, there were wound groups (24 h group and 48h group, 8/group, total 48 in six groups) and no wound groups (8/group, total 24 in three groups) . Except for the control group, the other groups were placed in cages at different distances under anesthesia, the experiment of gas explosion was carried out by placing the rats in a position that could force the lungs. The changes of respiratory function of the rats in the non-invasive group were monitored with pulmonary function instrument at 2 h, 24 h, 48 h, 72 h and 168h after the explosion, and were killed under anesthesia 7 days later; the rats in invasive groups were anesthetized and killed at 24 h, 48 h and 168 h, respectively. Gross observation, lung wet-dry ratio and lung histopathology were performed. Results: Compared with the control group, f (respiratory frequency, f) , MV (minute ventilation, MV) , PEF (peak expiratory flow rate, PEF) , PIF (peak inspiratory flow rate, PIF) and EF50 (1/2 tidal volume expiratory flow, EF50) of rats in the close and long range groups decreased significantly after gas explosion 2 h. PAU (respiration pause, PAU) , Te (expiratory time, Te) , Ti (inspiratory time, Ti) and Tr (relaxation time, Tr) were significantly increased (P<0.05) . After 48 h, TV (tidal volume, TV) , Penh (enhanced respiration pause, Penh) , PAU, and PIF of rats in the long range group were significantly increased (P<0.05) . After 72 h, MV in the long range group was significantly decreased (P<0.05) . Compared with the control group, Penh, PAU, Ti and Te were significantly decreased after 168 h in the close and long range groups, with statistical significance (P<0.05) . At the same time, the body weight of rats in different range groups was significantly decreased (P<0.05) . In addition, both HE staining and routine observation of lung tissues of rats in different range groups showed that gas explosion caused pulmonary edema, obviously congested pulmonary capillaries, a large number of inflammatory cells and infiltrated red blood cells. Conclusion: Gas explosion in real roadway environment can cause the change of respiratory function phase and lung tissue damage in rats, suggesting that the model of gas explosion-induced ABLI has been initially established successfully, which would provide a basis for further study on the pathogenesis of ABLI.

[Association between dust exposure and the risk of hypertension of male coal miners in Henan Province]

Objective: To explore the association between dust exposure and the incidence of hypertension in male coal miners. Methods: Using the method of retrospective cohort study,a hypertension cohort of colliery in Henan Province was established in January 2006. From 2006 to 2017,all the male coal miners in a colliery who were exposed to dust were selected into the exposure group including tunneling, mining,auxiliary and combining workers, and workers from administrative logistics departments who were not exposed to dust were selected into the control group. The eligible participants should satisfy following conditions: working more than one year, with clear and complete record of occupation change, and with complete archives and reliable diagnosis of occupational health surveillance. The exclusion criteria of participants were with hypertension at the baseline of study or with heart,liver,kidney diseases and malignant tumors. A total of 12 647 participants were enrolled in this study (11 663 in the exposure group and 984 in the control group). The follow-up period was from January 2006 to December 2017,with a total follow-up of 89 259.75 person-years. Questionnaires and physical measurements were used to collect general demographic characteristics, occupational exposure history and occupational health surveillance data of all participants. The Cox proportional hazards regression model was used to estimate the association between the dust exposure and the incidence of hypertension. Results: During the follow-up period, 2 549 new-onset hypertension patients were identified with an incidence density of hypertension about 2 855.71 per 100 000 person-years. The incidence density of hypertension was 2 967.58 per 100 000 person-years in the exposure group, and 1 643.85 per 100 000 person-years in the control group. The results of multivariate Cox proportional hazards regression model showed that after the adjustment of marriage, age, smoking, alcohol drinking and body mass index,the risk of hypertension was higher in the exposure group compared with the control group (HR=1.692, 95%CI: 1.410-2.032). Further analysis showed that compared with workers from administrative logistics departments,the risk of hypertension in tunneling,mining and auxiliary working was 1.629(1.345-1.973),1.677(1.374-2.046) and 1.782(1.475-2.151),respectively. Conclusion: Dust exposure may increase the risk of hypertension in male coal miners.

[Expression of type 1 and type 2 cytokines from serum of coal miners and the evaluation in surveillance of coal workers' pneumoconiosis at earlier stage]

Objectives: To explore the expression regulation of type 1 and type 2 (Th1 and Th2) cytokines from serum of coal miners and the evaluation in surveillance of coal workers' pneumoconiosis, 630 coal miners were studied. Methods: A total of 90 male patients diagnosed as coal workers' pneumoconiosis (CWP) in a institute for occupational health and 19 male workers newly diagnosed as CWP patients was chosen as CWP group with simple random sampling method from a coal mine group from January 2013 to December in 2015. 180 male coal miners with abnormal but not diagnosed as CWP were selected as CWP suspected group with simple random sampling methods, meanwhile 180 male coal miners with normal chest X-ray photograph was as dust-exposed group by 1∶1 matched as age. And 161 healthy males accepted pre-employed examination were selected as control group, CWP suspected group, dust-exposed group and control group called as non-CWP group. According to screening test and diagnosis test, the basic information and occupational history of all subjects were collected, and cytokines including IL-1β, IL-8, IFN-γ, IL-6 and IL-10 of serum were detected. Receiver operator characteristic (ROC) curve was used to determine the optimal cutoff value of each cytokine. Area under curve (AUC), the validity and reliability were calculated and judged. Results: The average age of control group, dust-exposed group, CWP suspected group and CWP group were (27.4±5.0) , (43.4±10.7) , (48.2±6.2) , (64.7±7.0) years old, respectively. The median level of IL-1β, IL-8, IFN-γ and IL-6 in cases group (1 638.30, 2 099.49, 815.18,140.32 pg/ml) were higher than that of non-cases group (1 445.57, 1 402.26, 736.38, 95.73 pg/ml) (P<0.05) . The level of IL-8 (1 503.99 pg/ml) in CWP suspected group was higher than that of control group (1 295.67 pg/ml) and dust-exposed group (1 376.94 pg/ml) , but the level of IL-10 (654.08 pg/ml) was lower than that of control group (596.64 pg/ml) . The ratio of IFN-γ/IL-6 ranged from 5 to 8, and the ratio in CWP group (5.87) was lower than that of non-CWP group (7.61) . The IL-6 and IL-8 among the subjects of dust-exposed group in terms of the age distribution of among had reached statistical significance. According to ROC, the cutoff value of IL-1β, IL-6, IL-8, IL-10 and INF-γ reached 1 582.65, 116.53, 1 791.54, 581.08 and 792.69 pg/ml, respectively. The AUC was 0.668, 0.895, 0.859, 0.716 and 0.637, respectively. It was found that IL-6 and IL-8 could be used as biomarkers in detecting CWP, the sensitivity and specificity was 82.6% and 84.6%, 78.0% and 84.8%, respectively; Youden's index was 0.674 and 0.628 and the consistency rate was 84.3% and 83.7%, while Kappa value was 0.55 and 0.52. Conclusion: There was Type 1 and type 2 cytokine dysregulation in CWP patients. IL-6 and IL-8 can be used as effective biomarkers to forecast lung injury before X-ray changes.

[Expression of AQP-1 and AQP-4 in the Lungs of Drown Rats]

OBJECTIVES

To observe the changes of expression of aquaporin-1（AQP-1） and AQP-4 in drowned and postmortem immersed rats' lungs.

METHODS

Thirty healthy male Wistar rats were randomly divided into drowning group, postmortem immersion group and cervical dislocation group. The morphological changes of rats' lungs were observed using HE staining. The mRNA and protein expressions of AQP-1 and AQP-4 in rats' lungs were detected by real-time PCR, immunohistochemistry and Western blotting, respectively.

RESULTS

The results of immunohistochemistry and the Western blotting showed that the protein expression of AQP-1 of the drowning group was higher than the postmortem immersion group and the cervical dislocation group （P<0.05）. The result of immunohistochemistry showed that the protein expression of AQP-4 of the drowning group was higher than the postmortem immersion group and the cervical dislocation group （P<0.05） while no difference were detected among the three of them by Western blotting （P>0.05）. The mRNA expressions of AQP-1 and AQP-4 in rats' lungs of the drowning group was significantly higher than the postmortem immersion group （P<0.05）.

CONCLUSIONS

The increase of mRNA and protein expressions of AQP-1 and AQP-4 in lungs of rats with cute lung injury of the drowning group would be useful for differentiating vital drowning from postmortem immersion.

Functionalized xenon as a biosensor

The detection of biological molecules and their interactions is a significant component of modern biomedical research. In current biosensor technologies, simultaneous detection is limited to a small number of analytes by the spectral overlap of their signals. We have developed an NMR-based xenon biosensor that capitalizes on the enhanced signal-to-noise, spectral simplicity, and chemical-shift sensitivity of laser-polarized xenon to detect specific biomolecules at the level of tens of nanomoles. We present results using xenon "functionalized" by a biotin-modified supramolecular cage to detect biotin-avidin binding. This biosensor methodology can be extended to a multiplexing assay for multiple analytes.

[A clinical study of autologous hematopoietic stem cells transplantation in 41 patients with leukemia and other malignant diseases]

41 patients (35 with leukemia, 4 lymphoma, 1 myeloma and 1 neuroblastoma) were treated with autologous hematopoietic stem cells transplantation. 8 patients were treated with autologous bone marrow transplant without purging (ABMT) 15 with autologous bone marrow transplant and purging (pABMT) and 18 with autologous blood hematopoietic stem cells transplant (ABHSCT). The mean hematopoietic reconstitution time was 60, 53, and 29.5 days respectively and the mean GM-CFU recovery time was 37, 44, and 30.5 days respectively in these three groups. The infection complication rates were 37.5%, 26.6% and 16.6% and the relapse rates were 37.5%, 30% and 18.7% respectively in the three groups. The results indicated that the ABHSCT had an earlier hematopoietic reconstitution time, a lesser infection complication rate and a lower relapse rate. Comparing with conventional chemotherapy, all the three transplant groups had an obviously longer disease-free survival time and a better curative effect.

Effects of exposure to trinitrotoluene on male reproduction

A cross-sectional study was performed in 2 plants located in Henan Province in 1990 for observing the reproductive and sexual functions of male workers exposed to trinitrotoluene (TNT). The TNT concentrations in the workplace air, except the packing site, were found to have exceeded MAC (1 mg/m3). TNT exposed male workers complained of more sexual disorders such as impotence, the loss of libido and sexual hypoesthesia than the control group. Compared with the control group, the volume of semen and percentage of motile spermatozoa were found to have significantly decreased, and the sperm malformation incidence increased significantly in TNT exposed workers. The serum testosterone content in TNT exposed male workers was significantly decreased too.

[Hemorrhagic cystitis in the course of hematopoietic stem cell transplantation]

Sixty patients consisting of 56 cases with leukemia, 3 with lymphoma and 1 with neuroblastoma were treated with various kinds of hematopoietic stem cell transplantation. The conditioning regimen consisted of mainly cyclophosphamide (CTX) and total body irradiation (TBI) with the addition of 1-3 doses of other antitumor drugs e.g. cytarabine, daunomycin, etoposide, 6-MP etc. The overall incidence of hemorrhagic cystitis in the course of transplantation was 23.3% (14 out of 60 patients). The time of onset of hematuria in 6 of 14 patients was within 1-4 days following high-dose CTX during conditioning and in the remaining 8 cases occurred 10-30 days after transplantation. The duration of hematuria lasted 2-31 days (mean, 4 days). Thirteen patients recovered and one patient died from the complication.

[Autologous peripheral hematopoietic stem cell transplantation in leukemia]

Six cases of acute leukemia patients were treated with APHSCT and the clinical results were satisfactory. The preparatory marrow ablative chemoradiotherapy regimen before APHSCT was same as that for autologous bone marrow transplantation (ABMT). The number of mononuclear cells infused to restore the hematopoietic function ranged from 1.65 to 2.92 x 10(8)/kg and these cells yielded 0.17 to 2.26 x 10(4)/kg CFU-GM. The hematopoietic and immunological function of patients returned to normal level 25 to 38 days after APHSCT; the recovery was faster than that of ABMT and FLT. One patient each died of recurrence of leukemia and fungi septicemia 90 and 70 days after transplantation respectively, whereas the other four patients have survived for 9, 8, 4, and 2 months respectively.