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In order to accurately master and understand the national occupational health standard Diagnosis for Occupational Radiation Thyroid Disease(GBZ 101-2020), the significance of the publication of this standard, the relevant background, the basic principles of the revision, the main basis for technical content revision, and the application of the standard are described. To provide guidance for t the physcians for occupational disease diagnosiss to understand the diagnostic principles, make correct diagnosis and avoid confusion in using the standard, so as to better protect the occupational health rights of radiation workers.
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Objective:To investigate chromosomal aberrations in peripheral blood lymphocytes of underground miners, in order to explore the influencing factors involved in chromosomal aberration levels of non-uranium metal mines.Methods:Totall 135 workers were recruited from an iron mine and a gold mine located in different cities of Henan province, where 69 workers worked aboveground and 66 miners worked underground in the metal mines. The radon concentration in the mines was measured by solid-state nuclear track detectors. Chromosomal aberrations in peripheral blood lymphocytes from the subjects were detected using conventional analysis method, and the influence factors of chromosomal aberrations were analyzed.Results:Radon concentration was 30-2 943 Bq/m 3 in the aboveground workplace of the mines, and 62-28 314 Bq/m 3 in underground. The age of the underground group was obviously lower than that of the aboveground group( t=2.12, P<0.05), but the frequencies of dicentrics, translocation, acentric fragment, and total chromosome-type aberrations in the underground group were significantly higher than those in the aboveground group ( χ2=10.49, 16.74, 8.15, 29.50, P<0.01). Consistent results were obtained when only male workers were regarded as object of observation ( χ2=8.44, 11.63, 4.94, 20.81, P<0.05). The frequency of translocation ( χ2=8.44, P<0.05) was dependent on the length of service in the underground group. Poisson regression analysis indicated that the aboveground and undergroud grouping partly affected the levels of dicentrics, translocation, acentric fragment, and total chromosome-type aberrations (the underground group IRR=3.25, 2.69, 1.97, 2.18, P<0.05). Conclusions:The radon exposure in the underground workplace of the metal mines may be the main factor resulting in the increase of chromosome-type aberrations of miners. The occupational health and safety of the miners who may be exposed to high radon levels are worthy of great attention.
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Objective:To investigate the effect of irradiation on the expression of miR-150-5p and miR-23a-3p in human peripheral blood serum by collecting peripheral blood of tumor patients before and after radiotherapy, so as to provide scientific basis for finding radiation biomarkers.Methods:A total of 63 tumor patients treated with radiotherapy from October 2021 to March 2022 were enrolled in this study. The relative expression levels of miR-150-5p and miR-23a-3p in peripheral blood serum in these patients were detected using the real-time fluorescence quantitative PCR (qPCR) before and after radiotherapy. The differential changes in the expression levels of the two miRNAs in the peripheral blood serum of the patients before and after radiotherapy were compared, and their relationships with factors such as cancer types were analyzed.Results:The relative expression levels of miR-150-5p and miR-23a-3p in peripheral blood serum of the patients after radiotherapy were significantly lower than those before radiotherapy ( t = 4.97, Z = -2.77, P < 0.05). Among different cancer types, the relative expression level of miR-150-5p in the patients with breast cancer, esophageal cancer, or other digestive tract cancer decreased after radiotherapy ( t = 3.47, 2.47, 2.87, P < 0.05), and the relative expression level of miR-23a-3p in the patients with digestive tract cancer decreased after radiotherapy ( Z = -1.99, P < 0.05). The changes in the expression level of miR-150-5p before and after radiotherapy were not affected by gender, age, chemotherapy, and cancer type ( P > 0.05). By contrast, the changes in the expression level of miR-23a-3p before and after radiotherapy were significantly affected by gender, age, and chemotherapy ( t=2.04, -3.34, -2.29, P<0.05). Conclusions:The expression of miR-150-5p in the serum of tumor patients may be affected by radiotherapy, which has the potential to be used as a biological indicator of radiation.
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The application of chromosome translocation to retrospective biodosimetry for A-bomb survivors, the victims previously exposed to nuclear/ radiation accident has experienced nearly 40 years of development. Retrospective biodosimetry was internationally paid close attention to radiation workers, exposed atomic veterans and medical exposure subjects, respectively, along with the development of molecular cytogenetic technology such as mFISH and cGH. And the remarkable breakthrough and progress have been made in recent years. This paper reviews the progress of translocation indicator as retrospective biodosimetry for the subjects, in order to provide a reference for retrospective dose estimation based on translocation analysis.
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Parental exposure to ionizing radiation (IR) can induce mutation in germline that may lead to genome instability, chromosomal aberrations, sex ratio variations, increased cancer susceptibility, and even increased probability of birth defects among their offspring, which substantially increase the burden of hereditary diseases. Up to now, the hereditary effect of IR has been observed in a number of species, but there is lack of evidence in humans. With reference to related studies in China and globally, this article reviews the human epidemiological studies of the hereditary effect of IR and briefly discusses why the hereditary effect of IR is not obvious in humans, so as to provide a reference for future assessment of the hereditary effect of radiation in China.
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Objective:To investigate the influence of low-dose ionizing radiation on the expression level of serum insulin-like growth factor binding protein-3 (IGFBP-3) in radiation workers in hospitals.Methods:183 radiation workers were randomly selected and grouped by work type including interventional radiology ( n=37), nuclear medicine ( n=43), radiotherapy ( n=48), and diagnostic radiology ( n=55). The content of IGFBP-3 in the serum of radiation workers was detected by ELISA assay. Results:It was observed that the expression level of serum IGFBP-3 in the four groups had significant differences ( F=6.056, P<0.05), and the content of serum IGFBP-3 in the interventional radiology group was significantly higher than that of nuclear medicine, radiotherapy, and diagnostic radiology groups ( t= 2.815, 3.611, 3.936, P<0.05). The concentration of IGFBP-3 in the serum of radiation workers among different annual effective dose groups was statistically different ( F=8.380, P<0.05), which gradually increased with the increase of annual effective dose and length of service ( rs=0.202, 0.151, P<0.05). Conclusions:The expression level of serum IGFBP-3 has the potential to be used as a biomarker to reflect the cumulative exposure of long-term chronic low-dose ionizing radiation.
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Objective:To carry out investigation and analysis of an extensive skin radiation injury to the back accidentally caused by interventional procedure and to explore the problems faced in the event with emphasis on avoiding the reoccurance of similar events in the future.Methods:The data were collected by consulting the patient′s detailed medical history, collecting and analyzing clinical diagnosis and treatment data, tracking and observing their clinical manifestations and signs. The patient′s peripheral blood samples were also collected, together with the biological dose estimated and the equipment data collected on the site of the interventional treatment hospital.Results:The whole body dose to the patient was estimated to be 0.95 Gy. The typical values of kerma rate of radiation incident on the body surface due to fluoroscopic procedures were 373.5 mGy/min in subtraction modality and 47.8 mGy/min in fluoroscopy modality, respectively. The annual effective dose to the interventional radiologist was 20.51 mSv due to his operation in long-time radiation exposure conditions, higher than 3.09 mSv for other interventional radiologists with similar workload in the same department. The whole body and local clinical manifestations of the patients were in line with radiation injury. No clear diagnosis has been obtained in several hospitals, nor can obvious treatment outcomes be obsevered.Conclusion:Combined with the biological dose estimation result and clinical manifestations, the case was diagnosed as degree Ⅳ skin radiation injury. Radiation injury is closely related to whether the operation is conducted according to the standard and the output dose of X-ray machine. Non-specialized hospitals should strengthen clinical diagnosis and treatment of radiation injury.
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Objective:To evaluate biological dose and retrospective biodosimetry of a case of large area back skin injury caused by suspected interventional procedure.Methods:Peripheral blood from the patient was collected at about 7 months after interventional procedure, and the chromosomal aberrations in peripheral blood cells were analyzed to evaluate the retrospective biodosimetry using the correction factor of dose estimation, Dolphin′s model and Qdr method, respectively. Results:Based on the amounts of semi-automated dic and manually detected dic plus ring, the whole-body average absorbed dose of the victim was estimated to be 0.68-0.95 Gy by four different dose response curves. Over dispersion of dic or dic plus ring was also detected, and the efficiency of dose assessment was obviously increased using dic semi-automatic detection. Based on three different retrospective biodosimetry models, the estimated average absorbed dose was further corrected to be between 1.80-2.86 Gy, which was consistent with clinical diagnosis of degree Ⅳ radiation skin injury.Conclusions:A case of suspected radiation skin injury was confirmed by chromosomal aberration analysis and it’s biodosimetry was reconstructed, suggesting that the unstable chromosomal aberration analysis may be applicable to assess the retrospective biodosimetry of non-uniform local radiation exposure.
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Objective@#To study the effects of sex, age, length of service, type of work and annual effective radiation dose on nucleoplasmic bridge (NPB) in the peripheral blood lymphocytes of radiation workers.@*Methods@#The peripheral blood samples of 100 radiation workers in Henan province were collected and the NPB in peripheral blood lymphocytes were measured by CBMN assay. The frequencies of NPB formation and NPB-containing cells were calculated, and the effects of various factors on NPB incidence were analyzed statistically.@*Results@#The NPB frequency in radiation workers was higher than that in healthy people (Z=-8.123, P<0.01). Except for sex, the factors of age, length of service, type of work and annual effective dose had significant influences on NPB (χ2= 7.202-45.571, P<0.05).@*Conclusions@#NPB reflects the effect of low-dose long-term chronic irradiation on the occupational radiation workers.
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Objective To study the effects of sex,age,length of service,type of work and annual effective radiation dose on nucleoplasmic bridge (NPB) in the peripheral blood lymphocytes of radiation workers.Methods The peripheral blood samples of 100 radiation workers in Henan province were collected and the NPB in peripheral blood lymphocytes were measured by CBMN assay.The frequencies of NPB formation and NPB-containing cells were calculated,and the effects of various factors on NPB incidence were analyzed statistically.Results The NPB frequency in radiation workers was higher than that in healthy people (Z=-8.123,P<0.01).Except for sex,the factors of age,length of service,type of work and annual effective dose had significant influences on NPB (x2=7.202-45.571,P<0.05).Conclusions NPB reflects the effect of low-dose long-term chronic irradiation on the occupational radiation workers.
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Objective:To explore the influence factors of chromosomal aberration levels in radiation workers in hospitals.Methods:Two hundred and fourteen age- and sex- matched hospital radiation workers were recruited by stratified random sampling method. According to the job title, the individuals were divided into four groups including diagnostic radiology group ( n=57), radiotherapy group ( n=49), nuclear medicine group ( n=52) and interventional radiology group ( n=56). Chromosomal aberrations in peripheral blood lymphocytes from the subjects were measured using conventional cytogenetic analysis method, and the influence factors of chromosomal aberrations were analyzed. Results:There was significant difference in the frequencies of acentric fragment, translocation and total chromosome-type aberrations among the four groups ( χ2=9.906, 19.965, 32.824, P<0.05), and the rates of aberrations were significantly higher in the interventional radiology group and the nuclear medicine groups than those in the diagnostic radiology (interventional group: χ2=4.711, 10.798, 10.845, P<0.05; nuclear medicine group: χ2=3.853, 7.674, 7.708, P<0.05) and the radiotherapy groups (interventional group: χ2=9.209, 9.772, 21.330, P<0.05; nuclear medicine group: χ2=8.010, 6.969, 10.812, P<0.05). The rates of translocation and total aberrations ( χ2=7.706, 6.667, P<0.05) and the frequencies of acentric fragment, translocation and total aberrations ( χ2=12.263, 15.360, 21.478, P<0.01) were dependent on the length of service and the dose among different groups. The rates of translocation and total aberrations significantly increased along with exposure doses ( r=0.347, 0.263, P<0.01). Poisson regression analysis indicated that the job titles and annual effective dose partly affected the levels of chromosomal aberrations[ IRR=1.797 (nuclear medicine group), 2.136 (interventional group) and 1.422 (0.5-1 mSv group); P<0.05]. Conclusions:The frequencies of chromosomal aberrations in the radiation workers of interventional and nuclear medicine groups remain higher levels in hospital, thus it is necessary to strengthen the radiation protection on these radiation workers.
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Objective:To investigate the late effects induced by external ionizing radiation through long-term follow-up of the victims exposed to 60Co radiation source at " 4.26" accident in Henan in 1999, and to provide valuable experience in the radiological medicine. Methods:Medical observations of the clinical symptoms, signs, eye lens examination and previous medical history of the five exposed victims were performed and recorded. The changes of the laboratory routine examinations, immune function, thyroid function, reproductive hormone levels, tumor markers, radiation genetic indicators as well as ultrasound examination of thyroid, cardiac, reproductive system, electrocardiogram, chest CT were systematically reviewed.Results:The typical radiation-induced cataract was found in " Mei" 2-3 years after 60Co accidental irradiation. 13 years after irradiation, the cataract surgery and intraocular lens implantation in left eye were performed followed by the same operation in right eye in November 2019. Different degrees phacoscotasmus under the posterior capsule or equatorial part of the eyes were also found in the rest of victims. ECG result of " Mei" indicated myocardial ischemia 7 years after accident. " Tian" confirmed diagnosis coronary heart disease 12 years after irradiation, and the surgery about coronary angiography heart stent implantation was taken at 20 years after irradiation. Five victims showed increased serum total cholesterol and/or triglycerides, and 4 victims showed bilateral or unilateral common carotid atherosclerotic plaque formation. Higher levels of thyroid stimulating hormone (TSH) were observed in " Mei" at 11 years after the irradiation. The thyroglobulin antibody (TGA)and thyroid microsomal antibody (TMA) were obviously increased in " Yi" , accompanied by thyroid uneven found by ultrasound. The thyroid nodules in " Mei" and " Min" were observed at 15 years after irradiation. The diagnosis of diffuse large B cell lymphoma(DLBL) in " Tian" was confirmed at 13 years after irradiation. Slightly higher of Neuron-specific enolase(NSE) were found in " Tian" , " Min" and " Yi" . A small nodule was detected from chest CT of " Tian" . Most of the chromosome aberrations observed in peripheral blood lymphocytes from the victims were stable chromosomal aberration such as translocation (t) with a few dicentric chromosome (dic) and acentric fragment (ace) in " Wang" and " Tian" . Conclusions:Ionizing radiation can cause variable degrees of deterministic effects in lens, thyroid gland and cardiovascular circulatory system and stochastic effects such as neoplasm. The genetic damages will last long in the patients.
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Objective:To explore the feasibility of using a High-Throughput Chromosome Automatic Scanning System (Metafer 4) to carry out automatic micronucleus detection for radiation workers.Methods:A total of 2 005 radiation workers selected were divided into five groups in terms of diagnostic radiology, radiotherapy, nuclear medicine, interventional radiology and industrial application.The Metafer 4 was used to assay micronuclei in peripheral blood lymphocytes from the subjects, with the factors affecting micronuclei analyzed. A total of 200 micronucleus samples collected by stratified random sampling were manually assayed for comparison of micronuclei frequency and detection efficiency between automatic and manual analysis.Results:The mean micronuclei frequency in 2 005 radiation workers were measured to be (0.92±0.02) ×10 -3. There was significant difference in the frequencies of micronuclei among the five groups ( χ2=11.054, P<0.05), with higher micronuclei frequency in interventional radiology group(1.00±0.03) ×10 -3 than in other groups ( χ2=5.568, 5.334, 7.689, P<0.05). Statistically significant difference could be observed in annual effective dose, length of service and micronuclei frequency among the radiation workers in different medical applications ( F=3.026, χ2=11.582, 8.878, P<0.05). A positive correlation between annual effective dose and micronucleus frequency was shown by Pearson analysis ( r=0.106, P<0.05). Multiple linear regression analysis showed that the automatic assay-based micronuclei frequencies were associated with length of service and work categories( r=9.485×10 -6, 5.660×10 -5, P<0.05), significantly lower when compared with manual analysis ( χ2=169.259, P<0.05). There was a consistency (ICC=0.713, P<0.05) between the two assay methods, but automatic analysis can increase the assayed micronucleus frequency by about 5 folds. Conclusions:The micronucleus frequency tested by automatic detection reflects genetic damage from low-dose chronic radiation exposure, and there may be feasibility of using automatic analysis to assay micronucleus of radiation workers.
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Objective:To explore the advantage of dose estimation based on semi-automated dicentric (dic) scoring and the feasibility of reflecting a large scale radiation accident for population clinical triage by mean of the comparison between semi-automatic and manual detection.Methods:Human peripheral blood samples from two healthy volunteers were irradiated by 60Co γ-rays at the doses of 0, 0.5, 1, 2, 3, 4, 5 and 6 Gy with a dose rate of 0.27 Gy/min, and chromosome preparation was carried out using the conventional method. The dic and dic plus ring were analyzed automatically with the DCScore software and manually with the Ikaros software, respectively, in a high-throughput chromosome automatic scanning system. The dose-response curves were fitted with dic or dic plus ring per cell. Twelve standard samples of biodosimetry were used to validate the dose-response curves. Results:The numbers of dic or dic plus ring per cell by semi-automatic or manual detection increased with the exposure doses ( r=0.984, 0.972, 0.972, P<0.01). The yields of semi-automated dic or manually detected dic plus ring were well fitted with the correlation coefficients ( R2=0.998, 0.999, 0.999, P<0.01). When the exposure dose of the standard samples was more than 2 Gy, the relative deviation between actual and predict doses was within 21% using the dose-response curve based on automated dic before human verification and correction of dic (elimination of false positives and inclusion of true positives), and wiht ±10% after manual elimination of false positive dic. Bio-doses estimated from the dic detected by manual scoring were similar to the actual exposure doses with the exception of 0.7 Gy, but the efficiency of semi-automatic analysis of dic was increased by 6-times in bio-dose assessment. Conclusions:The semi-automated dic detection obviously improves the level and efficiency of biodosimetry analysis, and thus can meet the requirements of clinical classification diagnosis of medical emergency response to large-scale nuclear radiation events.
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Objective To understand effects of the interventional operation on thyroid,peripheral blood indexes and chromosomal aberrations (CA) of peripheral lymphocyte of children with congenital heart disease (CHD).Methods Follow-up studies were conducted in 70 child patients undergoing cardiac catheterization and 23 with open heart surgery as control from 2010 to 2013.Postoperative follow-up examinations included thyroid ultrasound,blood routine indexes and analyses of CAs.Results Difference in thyroid ultrasound abnormality rate was not statistically significant between children with cardiac catheterization and control group (40.0% vs.43.5%,P > 0.05).There was no significant difference in white blood cell (WBC) count between interventional group and control group (P > 0.05).The effects of disease type and operation time on thyroid ultrasound and WBC count were not observed (P > 0.05).The frequency of chromosome aberrations,including acentric fragment,dicentrics and translocation in interventional group [(0.76 ± 0.07) %],was higher than in control group [(0.25 ± 0.07) %,(Z =-3.631,P < 0.05],and the rates of acentric fragment and translocation were also higher in interventional group (Z =-2.531,-2.397,P < 0.05).Conclusions Effect of intervention therapy on thyroid structure and WBC count in children with CHD was not observed,but the genotoxic effects remain in children with cardiac catheterization.
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Objective To explore the influence of long-term low-dose ionizing radiation on 8-hydroxy-2-deoxyguanosine(8-OHdG) level in the serum of radiation workers in hospitals.Methods 307 age-and sex-matched hospital radiation workers were recruited by stratified random sampling method.After deleting the subjects without dosage information,230 individuals were divided into four groups according to their job title [including diagnostic radiology (n =75),radiotherapy (n =60),nuclear medicine (n =41) and interventional radiology (n =54)].Serum 8-OHdG level was measured by ELISA assay.Results According to the statistical analysis,there was significant difference in the serum 8-OHdG level among four groups (F =9.071,P < 0.05),and the content of serum 8-OHdG was significantly higher in the interventional radiology group than that in the groups of diagnostic radiology,radiotherapy and nuclear medicine (t =-4.473,-3.011,-2.189,P < 0.05).There were significant differences in serum 8-OHdG level among different dose groups and working period groups(F =7.659,3.058,P < 0.05).The serum 8-OHdG levels significantly increased along with exposure dose and working period (r =0.300,0.142,P < 0.05).Conclusions Serum 8-OHdG may be a potential biomarker of oxidative DNA damage in radiation workers exposed to low-dose ionizing radiation.
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Long-term exposure to low dose ionizing radiation contributes to the damage of radiosensitive tissue and organ in radiation workers.The main cytogenetic index used to evaluate radiation damage induced by chronic low dose ionizing radiation is the chromosome aberrations of peripheral blood lymphocytes.In this paper,the cytogenetic evaluation indicators of radiation workers exposed to low dose ionizing radiation were reviewed basing on the research achievements of domestic and foreign scholars.The goals of this review were to supply the present situation and limitation of chromosomal aberration analysis in peripheral blood lymphocytes of radiation workers and to provide a reference for the chromosomal aberration test and assessment of radiation workers in China.
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Objective To observe late effect of 60Co radiation accident on eye lens in the victims.Methods Medical observations of eye lens were performed on ten victims accidentally exposed to 60Co sources in four radiation accidents that have occurred from 1986 to 2000 in Henan Province.Pathological changes of the eye lenses were examined by using slit lamp microscopy after mydriasis with compound tropicamide.Results Of these ten victims, Liang in a radiation accident in Kaifeng (in 1986), Mei in Xinxiang (in 1999) and Xu in Xuchang (in 2000) all had typical radiation-induced cataract 2, 3 and 6 years after irradiation, respectively.Follow-up observation of the lens showed the punctate and/or granular opacities present in the eye posterior subcapsular of Yan in Kaifeng accident, Jie in Zhengzhou (1987), and Tian, Yong and Yi in Xinxiang accident, featuring the early changes of radiation-induced cataract, but the posterior subcapsular opacities were not observed in Wang and Min in Xinxiang accident.Conclusions Focus should be on the eye lens as the target organ of radiation exposure in long-term follow-up of victims accidentally exposed to radiation source.Severity of the lens opacity induced by ionizing radiation is closely associated with radiation doses.
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<p><b>OBJECTIVE</b>To measure peripheral serum levels of matrix metalloproteinase 9 (MMP9) and matrix metalloproteinase 19 (MMP19) in patients with pneumoconiosis, and to investigate their feasibility as potential biomarkers for pneumoconiosis.</p><p><b>METHODS</b>Ninety-eight male patients with pneumoconiosis (49 patients in phase I, 36 patients in phase II, and 13 patients in phase III) were enrolled as subjects, which included 41 patients with silicosis and 57 patients with coal workers' pneumoconiosis. Ninety-eight healthy male physical examinees were used as controls. A fasting blood sample (3 ml) was collected from the peripheral venous blood of each patient or control, and the serum was separated from the blood sample. The expression levels of MMP9 and MMP19 in serum were measured by enzyme-linked immunosorbent assay.</p><p><b>RESULTS</b>Serum levels of MMP9 and MMP19 in patients with silicosis or coal workers' pneumoconiosis were significantly lower than those in the control group (P < 0.05). Serum levels of MMP19 in patients with silicosis were significantly higher than those in patients with coal workers' pneumoconiosis (P < 0.05). Serum levels of MMP19 in patients exposed to dust for less than 7 years were significantly higher than those in patients exposed to dust for more than 20 years (P < 0.05). There were no significant differences in serum levels of MMP9 and MMP19 between patients with different levels of pulmonary function impairment (P > 0.05). Serum expression levels of MMP9 and MMP19 were positively correlated with each other in both patients with pneumoconiosis and those in the control group (P < 0.05). The serum expression level of MMP9 was negatively correlated with the stage of pneumoconiosis (P < 0.05).</p><p><b>CONCLUSION</b>Serum MMP9 and MMP19 may be used as potential biomarkers for pneumoconiosis.</p>
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Humanos , Masculino , Antracose , Biomarcadores , Minas de Carvão , Poeira , Pulmão , Metaloproteinase 9 da Matriz , Sangue , Metaloproteinases da Matriz Secretadas , Sangue , Exposição Ocupacional , Pneumoconiose , Sangue , SilicoseRESUMO
Objective To analyze the differences in the clinical characteristics,endoscopy,pathology and therapy between the patients with new onset ulcerative colitis(UC) in the elderly versus youth and middle-aged patients.Methods A review analysis was carried out in the 178 hospitalized patients with UC in Third Hospital of Peking University from 1994 to 2010.The patients were divided into two groups according to the age of onset:UC onset at age of 60 years and older were enrolled in elderly group; UC onset at age less than sixty years were enrolled in youth and middle-aged group.The data of clinical manifestation,endoscopy,pathology,laboratory test,the severity of disease classification and therapy were analyzed and compared between the two groups.Results The elderly group consisted of 21 men and 6 women.The youth and middle-aged group consisted of 83 men and 68 women.The ratio of male was higher in elderly group than in youth and middle-aged group (77.8% vs.55.0%,P<0.05).No significant difference in the clinical type of UC was observed (P>0.05).The ratio of abdominal pain in elderly group was lower than in youth and middle-aged group (44.4% vs.78.8%,P<0.05).There were no significant differences in other symptoms,laboratory test and the severity of disease between the two groups (all P>0.05).The ratio of Grade Ⅰ and Ⅱwas much higher in the elderly than in youth-middle-aged group(70.4% vs.39.9%,P<0.05),but the ratio of Grade Ⅲ and Ⅳ was much lower in the elderly than in youth-middle group(29.6% vs.60.1%,P<0.05).No significant differences between the two groups were found in the extent of disease,pathological characteristics and therapy (all P>0.05).Conclusions Compared with the youth and middle-aged patients with onset UC,the ratio of male patients was higher,the ratio of abdominal pain was lower,and the severity of endoscopic manifestation was less in the elderly patients with onset UC.