Relationship between plasma SP-A expression level and disease stage in silicosis patients / 上海预防医学

ObjectiveTo investigate the relationship between plasma surfactant protein⁃A （SP⁃A） expression level and silicosis progression， and to provide early evidence for exploring whether SP⁃A can be used as a biomarker for clinical monitoring of silicosis disease progression. MethodsWe recruited 187 silicosis patients in Guangdong Province hospital for occupational disease prevention and treatment between November， 2019 and November，2020. Their peripheral venous blood samples were collected for the plasma isolation. The level of pulmonary SP⁃A was detected by enzyme-linked immunosorbent assay. ResultsThere was a statistically significant difference in the level of SP⁃A among the silicosis groups （P<0.05）， and the plasma SP-A level of the silicosis patients in stage Ⅲ was higher than that in stage Ⅰ and stage Ⅱ （P<0.05）. Smoking had effect on plasma SP⁃A levels， Age， working years and drinking had no effect on plasma SP⁃A levels. ConclusionThe expression level of SP⁃A in the plasma of silicosis patients is increased， which has a certain correlation with the disease stage， and plays a certain early warning role in the occurrence and development of silicosis， and may be a potential biomarker for the diagnosis and prognosis of silicosis.

Un caso poco frecuente: síndrome de Erasmus y tuberculosis / A rare case: Erasmus syndrome and tuberculosis

Resumen Presentamos el caso de un hombre de 35 años, are nador durante ocho años, con diagnóstico reciente de tuberculosis pulmonar y esclerosis sistémica, que ingre só por cuadro de disnea y mal estado general. Se realizó radiografía de tórax donde se evidenció neumotórax grado I, en la tomografía de tórax, también presentó masas hiperdensas confluyentes, asociadas a un patrón de neumonía intersticial no especifica (NSIP), hallazgos compatibles con silicosis pulmonar complicada. Debi do al avanzado estadio clínico, no pudieron realizarse estudios diagnósticos invasivos ni estudios de función pulmonar. Como tratamiento inicial se colocó un tubo de avenamiento pleural, se realizó tratamiento antifímico y se indicó oxigenoterapia crónica domiciliaria. Se remitió al paciente a consultorios de enfermedades intersticia les y reumatología para un manejo multidisciplinario, aunque el cuadro infeccioso contraindicó la posibilidad de un tratamiento inmunosupresor. Finalmente, el pa ciente falleció bajo cuidados paliativos. La inhalación de sílice es la causa de la silicosis, pero también está implicada en el desarrollo de la esclerosis sistémica (síndrome de Erasmus) y aunque comparten un factor de riesgo común, es raro encontrar ambas enfermedades coexistiendo. Presentamos el caso de un paciente joven donde ambas condiciones se presentaron de manera agresiva, con el objetivo de remarcar la importancia de la búsqueda activa de las enfermedades por exposición y sus condiciones asociadas.

Abstract We present the case of a 35-year-old male patient, sandblaster for eight years, recently diagnosed with pulmonary tuberculosis and systemic sclerosis, who was admitted with dyspnea and poor general condition. Chest X-ray showed a grade I pneumothorax, and on the chest tomography he presented confluent hyperdense masses associated with a pattern of non- specific in terstitial pneumonia (NSIP), findings compatible with complicated silicosis. Due to the advanced clinical stage, neither invasive diagnostic test nor pulmonary func tion test could be performed. Initial treatment included placement of a pleural drainage tube, antituberculosis treatment and chronic home oxygen. The patient was referred to the interstitial disease and rheumatology de partments for multidisciplinary management, although the infectious condition contraindicated the possibility of immunosuppressive treatment. The patient eventu ally died under palliative care. Silica inhalation is the cause of silicosis, but it is also implicated in the devel opment of systemic sclerosis (Erasmus syndrome) and although they share a common risk factor, it is rare to find both diseases coexisting. We present the case of a young patient in whom both diseases presented aggres sively, with the aim of highlighting the importance of actively searching for expositional diseases and associ ated conditions.

Occupational lung diseases in South African miners at autopsy: 2020 surveillance report

The Pathology Division at the National Institute for Occupational Health (NIOH) provides autopsy services for deceased workers who worked in controlled mines or works under the provisions of the South African Occupational Diseases in Mines and Works Act, 1973 (Act No. 78 of 1973). This report describes the ages, commodities, employment durations, and occupational cardio-respiratory diseases in miners whose organs were submitted for autopsies in 2019 and 2020. Data were exported from the PATHAUT database into STATA for analysis. Differences in the proportions of disease (expressed per 1 000) were calculated using the Pearson's chi-square test; significance was set at p ≤ 0.05. There were 759 and 557 records of deceased miners and ex-miners in 2019 and 2020, respectively. Pulmonary tuberculosis decreased from 192/1 000 in 2019 to 153/1 000 autopsies in 2020, and silicosis decreased from 246/1 000 to 223/1 000. However, neither decrease was significant. There was a significant increase in the rate of asbestosis from 50/1 000 in 2019 to 79/1 000 in 2020. Pulmonary tuberculosis (TB), emphysema, and silicosis were the most frequent diseases, with high rates. There was a non-significant decrease in occupational respiratory disease rates in 2020 from 2019, but these remain higher than the rates seen in the early 1990s. The NIOH continues to conduct autopsy surveillance on miners to support compensation for families, and the development of policy and intervention programmes in the mining industry

Analysis of serum CA125 and related influencing factors in silicosis patients with pulmonary heart disease / 中华劳动卫生职业病杂志

Objective: To analyze the serum carbohydrate antigen 125 (CA125) level and its influencing factors in male silicosis patients with pulmonary heart disease. Methods: In October 2021, data of 38 male patients with simple silicosis (silicosis group), 28 cases of silicosis with pulmonary heart disease (pulmonary heart disease group), and 27 healthy controls (control group) in the same age group were collected in inpatient and outpatient of Nanjing Occupational Disease Prevention and Control Hospital from January 2017 to December 2020. The serum CA125 levels of the three groups were compared, and the correlation between disease-related indexes and serum CA125 in silicosis patients with pulmonary heart disease was analyzed, as well as the influencing factors of pulmonary heart disease and serum CA125 levels in silicosis patients. Results: The serum CA125 level[ (19.95±7.52) IU/ml] in pulmonary heart disease group was higher than that in silicosis group[ (12.98±6.35) IU/ml] and control group[ (9.17±5.32) IU/ml] (P<0.05). There was no significant difference in serum CA125 level between the silicosis group and the control group (P>0.05). Serum CA125 levels were positively correlated with blood uric acid and fasting blood glucose in silicosis patients with pulmonary heart disease (r=0.39, 0.46, P<0.05). Serum CA125 level was a risk factor for silicosis patients with pulmonary heart disease (OR=1.13, 95%CI: 1.02-1.24, P<0.05). Dust exposure time, lactate dehydrogenase and smoking history were positively correlated with serum CA125 level in silicosis patients (P<0.05) . Conclusion: The serum CA125 level of male silicosis patients with pulmonary heart disease is significantly increased, and the level of CA125 is correlated with the level of fasting blood glucose and blood uric acid.

Research progress of thyroid hormone in pulmonary fibrosis / 中华劳动卫生职业病杂志

Pulmonary fibrosis is end-stage of variety of heterogeneous interstitial lung disease, characterizedby excessive proliferation of fibroblasts and extracellular matrix deposition and destruction of lung parenchyma. Thyroid and lung are derived from the same endodermal cells, thyroid hormone affect the occurrence、development and prognosis of the chronic obstructive pulmonary disease, lung cancer and other lung diseases, This article reviews the role and mechanism of thyroid hormone in pulmonary fibrosis in order to provide new idea for the study of the role and mechanism of thyroid hormone in silicosis.

Epidemiological characteristics of newly diagnosed occupational pneumoconiosis in Guangdong Province from 2011 to 2020 / 中国职业医学

Objective To analyze the epidemiological characteristics of newly diagnosed occupational pneumoconiosis (hereinafter referred to as "pneumoconiosis") in Guangdong Province from 2011 to 2020. Methods Clinical data of newly diagnosed pneumoconiosis in Guangdong Province from 2011 to 2020 was collected from the “Health Hazards Monitoring Information System” under “China Disease Prevention and Control Information System”. The distribution of the cases was analyzed retrospectively. Results A total of 2 731 cases of newly diagnosed pneumoconiosis were reported from 2011 to 2020 in Guangdong Province, with cases at stages Ⅰ,Ⅱ, and Ⅲ accounting for 61.6%, 23.8%, and 14.6%, respectively. Except for talc pneumoconiosis, 12 other types of pneumoconiosis were reported. The top three incidence of diseases were silicosis, other pneumoconiosis, and welder's pneumoconiosis, accounting for 58.8%, 22.0% and 11.0%, respectively. Males accounted for 97.5%, and females 2.5%. The median age of onset was 47 years old. The median dust exposure duration was 9.8 years, with 19.4% of cases having a dust exposure duration less than 5.0 years. And 80.7% of the cases were distributed in the Pearl River Delta region. The industries with the new cases were mainly the manufacturing (accounting for 69.4%), and 34.8% of cases were found in private limited liability companies. Cases in medium- and small-sized enterprises accounted for 35.7% and 34.3% respectively. Conclusion Silicosis, other pneumoconiosis, and welder's pneumoconiosis are predominant in Guangdong Province. The prevention and control of pneumoconiosis should focus on small- and medium-sized private enterprises in the concentrated manufacturing industry in the Pearl River Delta region.

Clinical characteristics of artificial quartz stone silicosis patients / 中国职业医学

Objectives To explore and compare the clinical characteristics and risk factors for mortality between patients with artificial quartz stone silicosis and those with classic silicosis. Methods A total of 48 patients with artificial quartz stone silicosis (experiment group) and 98 patients with classic silicosis (control group) were recruited as the research subjects using the convenience sampling method. Data of clinical symptoms, laboratory tests, high-resolution computed tomography (HRCT), and pulmonary pathology of the research subjects were retrospectively analyzed. The Cox proportional hazards regression model was used to analyze the influencing factors on the survival time of silicosis patients. Results Patients in the experiment group had shorter years of dust exposure, latency period and time since last exposure than those in the control group (all P<0.01). The positive rate of anti-nuclear antibodies and the expression of neuron-specific enolase in the experiment group were higher than those in the control group (39.6% vs 10.2%, median： 28.44 vs 16.25, both P<0.01). The PaO2 levels in the experiment group were lower than those in the control group (median： 66.0 vs 89.0, P<0.01). The patients in the experiment group had lower vital capacity, inspiratory reserve volume, forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), and carbon monoxide diffusion capacity compared to the control group (all P<0.05), but the maximal expiratory flow in 75% vital capacity was higher than the control group (P<0.05). Compared with the control group, patients in the experiment group had the presence of ground-glass opacity (GGO) in both lungs, aggregation and fusion of subpleural nodules, and gradual formation of progressive massive fibrosis (PMF), with higher potential of pneumothorax. Within 5 years after diagnosis, the mortality of patients in the experiment group was higher than that in the control group (27.1% vs 4.1%, P<0.01). The Cox regression model analysis results showed that patients with nodule aggregation on lung HRCT images had a higher risk of mortality than those without nodule aggregation, and lower lung function including vital capacity, FVC, FEV1 and maximum expiratory flow in 25% vital capacity had higher risk of reduced survival time (all P<0.05). Conclusion Compared with patients with classic silicosis, patients with artificial quartz stone silicosis have higher level of serum neuron-specific enolase, increasing the risk of autoimmune diseases. Pulmonary imaging features in patients with artificial quartz stone silicosis include GGO, PMF and susceptibility to pneumothorax, and rare calcification of mediastinal lymph nodes, leading to a higher mortality rate within 5 years after diagnosis.

Exploring the mechanism of action of curcumin in the treatment of silicosis based on network pharmacology and molecular docking / 中国职业医学

Objective To explore the mechanism of action of curcumin in the treatment of silicosis by network pharmacology combined with molecular docking technology. Methods The targets prediction network of curcumin in treating silicosis was established based on the collection of targets of curcumin and silicosis in multiple databases, cross-targets were submitted to the STRING database, and their connectivity was analyzed by Cytoscape software. Gene ontology (GO) function analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed on the top 20 genes. The molecular docking was performed on the key targets to study the mechanism of action of curcumin in treating silicosis. Results A total of 311 targets related to curcumin, 270 targets related to silicosis, and 74 cross-targets were obtained from the databases. GO function analysis revealed 2 665 related pathways, and KEGG pathway enrichment analysis revealed 188 related pathways. Molecular docking results showed that curcumin had good binding ability with the targets of mitogen-activated protein kinase 3 (MAPK3), interleukin (IL) 6, serine/threonine kinase 1 (AKT1), vascular endothelial growth factor A (VEGFA), signal transducer and activator of transcription 3, albumin, Jun proto-oncogene, tumor necrosis factor (TNF), IL1B, tumor protein p53, C-C motif chemokine ligand 2 and fibronectin 1. Conclusion The therapeutical effects of curcumin on silicosis were implemented through multi-targets and multi-pathways. Curcumin may play a role in the treatment of silicosis by binding to the core targets MAPK3, IL6, AKT1, VEGFA and TNF and regulating the MAPK, IL6, TNF, phosphatidylinositol 3-kinase/protein kinase B and VEGF signaling pathways.

Analyzing the current status of newly diagnosed occupational pneumoconiosis patients in Zhangdian District of Zibo City / 中国职业医学

Objective To analyze the distribution, survival conditions, and medical support of newly diagnosed occupational pneumoconiosis (hereinafter referred to as pneumoconiosis) patients in Zhangdian District, Zibo City. Methods A total of 1 189 newly diagnosed pneumoconiosis patients in Zhangdian District from 1956 to 2019 were selected as the study subjects using retrospective method. Data of their age of onset, years of occupational exposure, category of working industry, type of pneumoconiosis, and status of medical support was collected and analyzed. Results The median and the 25th-75th percentiles ［M (P25, P75)］ of the age of onset were 51.8 (45.5, 56.1) years, and the mortality was 37.0%. The majority of pneumoconiosis cases were silicosis (45.2%) and coal workers' pneumoconiosis (39.8%). The highest prevalence of pneumoconiosis was in the coal mining and washing industry (42.4%), followed by manufacturing (33.4%). Pneumoconiosis patients in stage Ⅰ,Ⅱ, and Ⅲ accounted for 89.1%, 8.7%, and 2.2%, respectively. The M (P25, P75) of the length of work exposed to dust were 24.1 (16.5, 29.9) years.The higher stage of pneumoconiosis the shorter of the length of work exposed to dust among these pneumoconiosis patients(all P<0.05). The overall survival rate, the 5-year survival rate and the 10-year survival rate of these pneumoconiosis patients were 63.0%, 92.3% and 85.9%, respectively. Among the 749 surviving cases, 60.8% were aged 60.0 to <80.0 years. In terms of social security, 100.0% surviving cases enjoyed basic medical insurance, meanwhile, 96.1% and 81.8% patients were covered by major medical insurances and occupational injury insurances, respectively. The M (P25, P75) of age at death were 73.1 (64.0, 77.1) years. The main causes of death were respiratory diseases (59.3%) and malignant tumors (20.4%). Conclusion The prevalent types of pneumoconiosis in Zhangdian District, Zibo City, are coal workers' pneumoconiosis and silicosis. Medical support and assistance are relatively limited. The pneumoconiosis prevention and control focus should be on silicosis and coal workers' pneumoconiosis, particularly in the manufacturing industry.

A case report of stage Ⅲ silicosis complicated by pulmonary tuberculosis and secondary pneumothorax treated with minimally invasive thoracoscopic surgery / 中国职业医学

Objective To analyze the feasibility of using minimally invasive thoracoscopic surgery to treat stage Ⅲ silicosis complicated by pulmonary tuberculosis and secondary pneumothorax. Methods This study retrospectively analyzed the clinical data of a patient with stage Ⅲ silicosis complicated by pulmonary tuberculosis and secondary pneumothorax. Results The patient had stage Ⅲ silicosis complicated with active pulmonary tuberculosis for 1.5 years. In March 2021, a left-sided pneumothorax occurred and was conservatively treated with closed chest drainage. In April 2022, the patient was admitted with sudden frequent coughing and left-sided chest discomfort. Based on occupational history, dust exposure history, high-kilovolt anterior-posterior chest radiography, chest computed tomography, and sputum smear results, the diagnosis was "stage Ⅲ silicosis; active tuberculosis (positive for acid-fast bacilli in sputum smear); left-sided pleural effusion, pulmonary bulla rupture; secondary pneumothorax (recurrent tension type in left, encapsulated in right); left pleural adhesion". On the second day of admission, left-sided closed chest drainage was performed with poor outcome. On the fifth day of admission, minimally invasive thoracoscopic treatment was performed, including left lung volume reduction, pleural adhesion cauterization, and pleural fixation. Postoperative anti-inflammation, anti-tuberculosis, and symptomatic supportive treatments were administered. Due to the patient's severe underlying disease, wound healing was slow postoperatively, but no serious complications occurred. The pneumothorax completely absorbed and recovered in 17.0 days. Conclusion Minimally invasive thoracoscopic surgery is an effective treatment for silicosis complicated with pulmonary tuberculosis and secondary pneumothorax, and it is worth promoting.

Research progress on using traditional Chinese medicine and extracts for activating blood circulation in prevention and treatment of silicosis / 中国职业医学

Occupational silicosis features as irreversible pulmonary fibrosis, which is caused by long-term inhalation of free silica dust. The pathogenesis of silicosis is complex and there is no cure at present. Traditional Chinese medicine classifies silicosis fibrosis into the category of diseases as "pulmonary paralysis" and "pulmonary arthralgia", and its treatment is based on promoting blood circulation and activating qi. Traditional Chinese medicine for activating blood circulation is one of the commonly used medications, which has the effects of anti-oxidation, anti-inflammation, anti-fibrosis and immunomodulation, and has broad application prospect in the prevention and treatment of silicosis. At present, animal experiments and clinical studies have been carried out using the single Chinese herbs extracts that could activate blood circulation such as Salvia miltiorrhiza, Ligusticum chuanxiong Hort., Panax notoginseng, Curcuma longa L., peach kernel and Carthamus tinctorius L. as well as their compound herbs for the prevention and treatment of silicosis. The mechanisms of anti-pulmonary fibrosis and the efficacy and safety of treating silicosis and its complications were explored. There are also scholars studying Salvia miltiorrhiza, Curcuma longa L. and Danhong injection, Taohong Siwu Decoction and others for prevention and treatment of pulmonary fibrosis. Additionally, network pharmacological research, analyzing potential targets and pathways, were carried out to provide scientific rationale for prevention and treatment of silicosis. However, the effectiveness of research is still uncertain, and it cannot meet the clinical needs. In the future, it is necessary to explore the application of more high-quality active components of traditional Chinese medicine monomer or mixture of activating blood circulation in the prevention and treatment of silicosis, to provide new ideas and scientific basis for the prevention and treatment of silicosis using traditional Chinese medicine.

Analyzing the distribution characteristics of occupational pneumoconiosis in Sichuan Province, 2012-2021 / 中国职业医学

Objective: To analyze the distribution feature of occupational pneumoconiosis in Sichuan Province. Methods: The cases of newly diagnosed occupational pneumoconiosis from 2012 to 2021 in Sichuan Province were collected from the Occupational Diseases and Hazards Monitoring Information System under China Disease Prevention and Control Information System, and were analyzed retrospectively. Results: From 2012 to 2021, there were 30 136 newly diagnosed occupational pneumoconiosis cases in Sichuan Province. The average age of patients was 55.2 years and the median work age was 12.1 years. There were 6 471 cases (accounting for 21.5%) exposed to dust for less than 5.0 years. The number of the cases declined in newly diagnosed occupational pneumoconiosis and occupational pneumoconiosis with less than 5.0 years of dust exposure. The numbers of coal workers' pneumoconiosis and silicosis were 16 210 and 13 577, respectively (accounting for 98.9% of the total cases). The majority of pneumoconiosis cases were classified as stage Ⅰ(accounting for 67.1%). The cases from Leshan City, Bazhong City, Dazhou City, Yibin City, Guangyuan City and Luzhou City accounted for 68.8% of the total cases. The main types of work were coal miner and excavation worker, which accounted for 31.7% and 18.8%, respectively. The scale of enterprises was mostly small and micro, accounting for 35.1% of the cases, and the industry distribution was mostly coal mining and washing, accounting for 53.4% of the cases. Conclusion: In Sichuan Province, the number of cases shows an overall decline in both newly diagnosed occupational pneumoconiosis and occupational pneumoconiosis with less than 5.0 years of dust exposure, with a relatively short duration of occupational exposure. The key cities for pneumoconiosis prevention and control are Leshan City, Bazhong City, and Dazhou City, while the key industry is coal mining and washing.

Survival analysis on patients with occupational pneumoconiosis in Guangdong Province from 1980 to 2019 / 中国职业医学

Objective: To study the survival time and its risk factors of patients with occupational pneumoconiosis. Methods: A total of 11 011 newly diagnosed occupational pneumoconiosis patients in Guangdong Province from 1980 to 2019 were selected as study subjects. The life table method was used for survival analysis. The influencing factors of survival time of occupational pneumoconiosis patients were analyzed using the WilCoxon (Gehan) test and Cox proportional hazards regression model. Results: The median survival time of pneumoconiosis patients was 26.0 years. The median survival period of stage Ⅰpatients was 3.5 years longer than that of stage Ⅱ patients and 10.1 years longer than that of stage Ⅲ patients. The median survival time of patients with an initial diagnosis age under 40.0 years old was 34.8 years longer than that of patients with an initial diagnosis age over 60.0 years old. The median survival time of patients with dust exposure duration under 25.0 years old was 13.6 years longer than patients with dust exposure duration age over 45.0 years old. The results of the Cox proportional hazards regression model showed that the initial diagnosis stage, initial diagnosis age, dust exposure duration, and medical insurance were risk factors of the survival time of occupational pneumoconiosis patients (all P<0.01). The risk of reduced survival time for patients with stage Ⅱ and stage Ⅲ as the initial diagnosis stage was 1.15 and 2.04 times higher, respectively, compared with stage Ⅰ patients (both P<0.01). The risk of reduced survival time for patients without medical insurance was 60.22 times higher than those with medical insurance (P<0.01). Conclusion: The risk factors of the survival time of occupational pneumoconiosis patients in Guangdong Province are initial diagnosis stage, initial diagnosis age, the dust exposure age, and medical insurance. Earlier detection, earlier diagnosis, and improvement of medical insurance coverage for patients can effectively improve the survival time of occupational pneumoconiosis patients.

Study on changes in complete blood cell count parameters of patients with occupational silicosis / 中国职业医学

{L-End}Objective To study the changes of complete blood cell count parameters and its influencing factors in patients with occupational silicosis (hereinafter referred to as "silicosis"). {L-End}Methods A total of 354 silicosis patients were selected as the research subjects using judgment sampling method. The patients were divided into stage Ⅰ, stage Ⅱ and stage Ⅲ groups according to the stage of silicosis. Based on the course of the disease, they were divided into groups of ≤3, >3-≤6, >6-≤9 and >9-≤12 years. The peripheral blood of the patients was collected for complete blood cell count analysis, and the influencing factors of complete blood cell count were analyzed by multiple linear regression model. {L-End}Results The levels of hemoglobin and the average red blood cell hemoglobin in patients with silicosis at stage Ⅱ and Ⅲ groups were lower than those at stageⅠgroup (all P<0.05). The percentage and counts of neutrophils increased in patients at stage Ⅲ group (all P<0.05), while the percentage and counts of lymphocytes decreased (all P<0.05) compared with those in stage Ⅰand Ⅱ groups. The percentage of eosinophils in patients at stage Ⅲ was lower than those at stage Ⅰ group (P<0.05). The red blood cell count in the courses of silicosis >6-􀰤9 years group was lower (P<0.05), and the percentage of neutrophils was higher, while the percentage of lymphocyte was lower in the courses of silicosis >6-􀰤9 years group and >9-􀰤12 years group (all P<0.05) compared with the courses of silicosis ≤3 years and >3-􀰤6 years groups. The mean corpuscular volume of the courses of silicosis >6-􀰤9 years group and the neutrophil count of the courses of silicosis >9-􀰤12 years group increased (all P<0.05) compared with the courses of silicosis ≤3 years group. The results of multiple linear regression analysis showed that the silicosis stage and course of silicosis were influencing factors of erythrocyte count (all P<0.05), gender and age of first dust-exposure were influencing factors of hemoglobin level (all P<0.05), while age at diagnosis, duration of dust-exposure, age of first dust-exposure and comorbidities were influencing factors of neutrophil count (all P<0.05). Gender, comorbidities, smoking and silicosis stage were influencing factors of lymphocyte count (all P<0.05). {L-End}Conclusion There are differences in complete blood cell count parameters in patients with silicosis at different stages and courses of the disease. Silicosis stage, course of disease, gender, age, smoking,comorbidities, duration of dust-exposure and age of first dust-exposure were influencing factors affecting complete blood cell count in silicosis patients.

Low dose metformin delays silicosis-induced pulmonary fibrosis in mice / 中国职业医学

{L-End}Objective To investigate the effect and mechanism of low dose metformin in delaying pulmonary fibrosis in silicosis mice. {L-End}Methods The specific pathogen free C57BL/6 male mice were randomly divided into four groups,with six mice in each group. Mice in the silicosis model group and the metformin intervention group were given 20 μL of a mass concentration of 250 g/L silica suspension, and mice in the blank control group and the drug control group were given 20 μL of 0.9% sodium chloride solution, using tracheal exposure method. After 72.0 hours of dust exposure, the mice of drug control group and metformin intervention group were intraperitoneally injected with metformin at a dose of 65 mg/kg body mass, while the mice in the blank control group and the silicosis model group were given 0.9% sodium chloride solution at the same volume, once every other day for 28 days. After the treatment, histopathological change of the lungs was observed, lung organ coefficient was calculated, degree of pulmonary fibrosis was evaluated with Ashcroft score, and mRNA expression of fibronectin (Fn)1 and collagen typeⅠ(COLⅠ) alpha 1 (Col1a1) in lung tissues were detected by real-time fluorescence quantitative polymerase chain reaction. The relative expression of FN and COLⅠ in lung tissues was determined by Western blot. {L-End}Results The results of histopathological examination of the lungs showed that there were no inflammation and fibrosis in the lungs of mice in the blank control group and the drug control group; mice in silicosis model group had inflammation and fibrosis in lung; the degree of lung inflammation and fibrosis was reduced in the mice of metformin intervention group compared with the silicosis model group. The lung organ coefficient, Ashcroft score, the relative expression of Fn1 and Col1a1 mRNA, the relative expression of FN and COLⅠprotein in lung tissues increased in silicosis model group (all P<0.05), compared with those in both blank control group and drug control group. The indexes above decreased of mice in the metformin intervention group than those in the silicosis model group (all P<0.05). {L-End}Conclusion Low-dose metformin can delay the progression of pulmonary fibrosis in silicosis mice. The mechanism may be related to metformin's improving excessive deposition of extracellular matrix induced by silica.

Hydrogen intervenes early inflammation of silicosis through the NF-κB/NLRP3 signaling pathway / 中国职业医学

{L-End}Objective To study the intervention effect of hydrogen on early inflammation in a rat silicosis model and its mechanism. {L-End}Methods Wistar rats of specific pathogen free were randomly divided into the control group, model group, tetrandrine group, hydrogen group and combined intervention group, with 10 rats in each group. The rats in the last four groups were treated with a dose of l.00 mL silica suspension with a mass concentration of 50.0 g/L by a one-time non-exposed tracheal method. The rats in the control group were given 0.9% sodium chloride solution in equal volume. After 24 hours of dust exposure, rats of the tetrandrine group were given 30 mg/kg body mass tetrandrine by gavage daily, rats of the hydrogen group were given 66.6% hydrogen inhalation continuously for four hours daily, rats of the combined intervention group were given the same interventions as the rats in the tetrandrine group and the hydrogen group, rats in the control group and model group were given 0.9% sodium chloride solution in equal volume by gavage. After 14 days of treatment, the lung coefficient of rats was determined, and lung histopathology was performed. The level of malondialdehyde in serum was detected by colorimetry. The level of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in serum were detected by enzyme-linked immunosorbent assay. The relative expression of nucleotide-binding oligomerization domain-like receptor thermal protein domain associated protein 3 (NLRP3), nuclear factor-κB (NF-κB) p65, NF-κB phosphorylated p65 (NF-κB p-p65), cysteinyl aspartate specific proteinase1 (Caspase1) and apoptosis-associated speck-like protein containing a CARD (ASC) in serum were detected in lung tissues by Western blot. The relative expression of NLRP3 and NF-κB p65 in lung tissues were detected by immunohistochemistry. {L-End}Results The result of pulmonary histopathology showed that the model group had obvious alveolar rupture and fusion, interstitial lymphocyte and macrophage infiltration, and alveolar wall thickening, collagen fibre deposition, and mild fibrotic hyperplasia, compared with the control group. The pathological outcomes of lung tissues in the three treated groups were alleviated compared with the model group, and the alveolar structure was more complete and the alveolar wall was thinner and the fewer collagen fibres in the rats of combined intervention group, compared with tetrandrine group and hydrogen group. The lung coefficient and Szapiel score of rats of the tetrandrine group, hydrogen group and combined intervention group were lower than those of the model group (all P<0.05). The levels of serum malondialdehyde, TNF-α and IL-1β in lung tissues, and the relative expression of NLRP3, NF-κB p65, NF-κB P-p65, Caspase1 and ASC in lung tissues increased in the model group, compared with the control group (all P<0.05). The indexes above decreased in the three treated groups than those in the model group (all P<0.05). The indexes above decreased in the combined intervention group than those in the tetrandrine group and hydrogen group (all P<0.05), except for the level of malondialdehyde in serum and the relative expression of NF-κB p-p65 in lung tissue. {L-End}Conclusion Hydrogen can intervene the early inflammation of silicosis through NF-κB/ NLRP3 signaling pathway.

Changes of biomarkers in plasma of patients with occupational silicosis and their diagnostic value / 中国职业医学

{L-End}Objective To analyze the changes of seven potential biomarkers in plasma of patients with occupational silicosis (hereinafter referred to as "silicosis"), and explore their clinical value in determining the stage of silicosis. {L-End}Methods A total of 100 male silicosis patients were selected as the silicosis group (63 cases in stage Ⅰ and 37 cases in stage Ⅱ subgroups), and 100 male healthy individuals were selected as the control group using the 1∶1 matched case-control study. Enzyme-linked immunosorbent assay was used to analyze the level of interleukin-17 (IL-17), monocyte chemoattractant protein-1 (MCP-1), matrix metalloproteinase-9 (MMP-9), Krebs von den Lungen-6 (KL-6), connective tissue growth factor (CTGF), platelet-derived growth factor (PDGF), and histone H4 in plasma. Their clinical value for diagnosing silicosis was evaluated using receiver operating characteristic (ROC) curve, discriminant analysis stepwise method, and Fisher discriminant function analysis. {L-End}Results The levels of IL-17, MCP-1, MMP-9, KL-6, CTGF, PDGF, and histone H4 in the plasma of the silicosis group, silicosis stage Ⅰ subgroups, and stage Ⅱ subgroups were higher than those in the control group (all P<0.05). The levels of IL-17, MCP-1, and MMP-9 in the plasma of the stage Ⅱ subgroup decreased (all P<0.05), while the levels of KL-6, CTGF and histone H4 increased (all P<0.05) compared with the stage Ⅰ subgroup. The area under the ROC curve for diagnosing silicosis using these seven potential biomarkers ranged from 0.761 to 1.000 (all P<0.01), with the sensitivity of 0.640-1.000, the specificity of 0.840-0.990, and the Youden index of 0.540-0.990. The Fisher discriminant function was formed by stepwise discriminant analysis, and the results showed that the coincidence rate was 99.5%, and the misdiagnosis rate was 0.5% for diagnosing and staging silicosis with these seven potential biomarkers. The coincidence rate of diagnosing control group, silicosis stageⅠsubgroup and the silicosis stage Ⅱ subgroup was 100.0%, 98.4% and 100.0%, respectively. {L-End}Conclusion IL-17, MCP-1, MMP-9, KL-6, CTGF, PDGF and histone H4 in plasma can be used as biomarkers for the diagnosis of silicosis, and the Fisher discriminant function based on the combination of these seven biomarkers can assist in staging silicosis.

Analysis of epidemiological characteristics of newly diagnosed occupational pneumoconiosis in Henan Province from 2006 to 2020 / 中国职业医学

Objective: To analyze the epidemiological distribution of new occupational pneumoconiosis (hereinafter referred as pneumoconiosis) in Henan Province from 2006 to 2020. Methods: Clinical data of newly recruited pneumoconiosis cases from 2006 to 2020 in Henan Province were retrospectively analyzed. Results: A total of 9 624 cases of newly diagnosed pneumoconiosis were reported in Henan Province in the past 15 years, of which 98.6% were males. The number of cases had two peaks, one in 2009-2011 and the other in 2014-2017. There were 12 types of pneumoconiosis of all reported cases except for mica pneumoconiosis, in which coal workers' pneumoconiosis and silicosis accounted for 96.0%. The incidence of phase Ⅰ, Ⅱ and Ⅲ pneumoconiosis was 64.7%, 21.0% and 14.3%, respectively. The incidence of phase Ⅱ and Ⅲ silicosis was higher than that of coal miners' pneumoconiosis (56.3% vs 22.7%, P<0.01). Patients with pneumoconiosis were mainly distributed in Zhengzhou City, Sanmenxia City, Luoyang City, Pingdingshan City and Hebi City, accounting for 85.0%. The enterprises involved were mainly mining industry, large- and medium-sized enterprises, state-owned enterprises and collective enterprises. The top five position of patients were coal miners, rock drillers, excavators, coal mixed workers and pure coal miners, total accounting for 72.0%. There were 196 enterprises reported ≥10 cases, accounting for 17.2% of all enterprises and 80.3% of the total of newly diagnosed pneumoconiosis cases. The median (M) of onset age of new cases was 49 years old, and the M of onset of working age was 16 years. The onset age of silicosis was younger (M: 49 vs 48 years old, P<0.05), while the onset of working age was longer (M: 10 vs 20 years, P<0.05), compared with that of coal workers' pneumoconiosis. Conclusion: The incidence of pneumoconiosis in Henan Province were disease clustering distribution, regional distribution, industry of enterprise, enterprise scale, enterprise type, nature and working position distribution of enterprises. And it showed the characteristics of group incidence. The prevention and control treatment of pneumoconiosis should be strengthened in key areas, key enterprises and key diseases and jobs.

The role of surfactant associated protein-A in silicosis / 中国职业医学

Objective: To investigate the role of surfactant associated protein-A (SP-A) in the development and progression of silicosis, and its mechanism. Methods: Homozygous and heterozygous mice of SP-A knockout of specific pathogen free (SPF) grade were selected for mating, and mice with SP-A-/- genotype were selected for subsequent experiments. SP-A wild-type (SP-A+/+) and SP-A-/- mice were divided into SP-A+/+ control group, SP-A-/- control group, SP-A+/+ silicosis group and SP-A-/- silicosis group with six mice in each group by random number table method. Mice in both silicosis groups were given 20.0 μL 250 g/L silica suspension by tracheal exposure, and mice in both control groups were injected with 0.9% sodium chloride solution at the same volume. On the 28th day after modeling, mice were sacrificed. Lung tissues were used for lung histopathology examination. The apoptosis of alveolar type Ⅱ epithelial cells of mice was detected by TUNEL method. The mRNA expression of B-lymphoblastoma 2 (Bcl-2), Bcl-2 associated X protein (Bax), cysteinyl aspartate specific proteinase (Caspase)-3 and Caspase-9 in lung tissues of mice was detected by quantitative real-time polymerase chain reaction. Results: The histopathological result of mice showed that thickened alveolar septum, scattered silicon nodule and collagen fiber formation were observed in the mice lungs of SP-A+/+ silicosis group, and a large number of inflammatory cells were observed in silicosis nodule, after exposure to silica dust. SP-A-/- silicosis group resulted in a more severe pulmonary inflammation and interstitial fibrosis compared to SP-A+/+ silicosis group. The apoptosis of alveolar type Ⅱ epithelial cells and the mRNA relative expression levels of Bax, Caspase-3 and Caspase-9 in lung tissues of mice in each silicosis groups were increased compared with their control groups (all P<0.05). The above four indexes of mice in SP-A-/- silicosis group were higher than those in SP-A+/+ silicosis group (all P<0.05). There was no significant difference in the expression of Bcl-2 mRNA in lung tissues of these four groups (P>0.05). Conclusion: Knockout of SP-A can aggravate inflammation and pulmonary fibrosis in silicosis model mice, and promote apoptosis of alveolar type Ⅱ epithelial cells. The mechanism may be related to the Bcl-2/Bax/Caspase-3 signaling pathway which affects the apoptosis of mitochondrial pathway.

Establishment of mouse silicosis fibrosis model by non-exposed tracheal perfusion / 中国职业医学

Objective: To establish a convenient non-invasive tracheal perfusion method for constructing a mouse model of silicosis-induced pulmonary fibrosis. Methods: The specific pathogen-free C57BL/6 mice were randomly divided into control group and model group, with 15 mice in each group. After anesthesia, a 22G arteriovenous indwelling needle was used to inset into the trachea through the mice's mouth. The model group mice were perfused with 0.1 mL of silica suspension with a mass concentration of 25 g/L, and the mice in the control group were perfused with an equal volume of 0.9% sodium chloride solution. On the 7th, 14th, and 30th day after modeling, the body weight of the mice was measured, and the lung tissue morphology and pathological changes were observed. The expression of α-smooth muscle actin (α-SMA) and collagen type 1 alpha 1 (COL1A1) protein in lung tissue of mice was detected by immunofluorescence on the 30th day after modeling. Results: There was no death of mice in the two groups during the experiment. There was no significant difference in body weight between the two groups (P>0.05). The lung tissues of the mice in the model group were pinkish-gray and uneven in color on the 7th and 14th days after dust exposure. On the 30th day after dust exposure, the lung tissue of the mice in the model group was gray and hard, and unevenly distributed silicon nodules were visible by the naked eyes. The histopathology results of lung tissue showed that compared with the mice in control group, the model group mice exhibited persistent aggravation of pulmonary inflammation, thickening of alveolar septum, infiltration of inflammatory cells gradually clustering into clumps, and an increasing number of fibrous foci.On the 30th day after dust exposure, the relative expression of α-SMA and COL1A1 proteins in the lung of the model group was higher than those in the control group (median： 72.59 vs 5.91, 35.62 vs 10.07, both P<0.05). Conclusion: The method of tracheal perfusion silica suspension of mice using 22G arteriovenous indwelling needle can successfully construct an animal model of silicosis fibrosis. This method is convenient, safe and effective, and is worth promoting.