[The mediating role of worker-occupation fit between occupational stress and anxiety symptoms in medical staff]

Objective: To analyze the mediating effect of work-occupation fit between occupational stress and anxiety symptoms in medical staff. Methods: Convenience sampling method was adopted to select participants of one general hospital and three specialized hospitals as respondents for a questionnaire survey in Henan Province from October 2020 to January 2021. A total of 2050 medical staff were investigated, and 1988 valid questionnaires were collected, and the effective rate of the questionnaire was 97.0% (1988/2050) . The "Depression-Anxiety-Stress Scale" and "Worker-Occupation Fit Inventory" were used to evaluate the occupational stress, anxiety symptoms and worker-occupation fit level of medical staff, and the mediation effect of work-occupation fit on the relationship between occupational stress and anxiety symptoms was analyzed using a mediating effect model. Results: The average age of the 1988 medical staff was (32.7±7.8) years old, the positive detection rates of occupational stress and anxiety symptoms were 42.5% (845/1988) and 56.7% (1127/1988) , respectively. Anxiety symptoms of medical staff were positively correlated with occupational stress, negatively correlated with worker-occupation fit (r=0.831, -0.364, P<0.001) , work-occupation fit was negatively correlated with occupational stress (r=-0.259, P<0.001) . The results of the mediation effect analysis showed that occupational stress had a direct effect on anxiety symptoms (β=0.677, BCa 95%CI: 0.648-0.707) , and worker-occupation fit (β=0.047, BCa 95%CI: 0.039-0.056) , characteristic fit (β=0.089, BCa 95%CI: 0.074-0.104) , need-supply fit (β=0.075, BCa 95%CI: 0.062-0.089) , and ability-demand fit (β=0.035, BCa 95%CI: 0.026-0.044) mediated the association between occupational stress and anxiety symptoms in medical staff, with the mediating effect as a percentage of 6.5%, 12.3%, 10.3%, and 4.8%, respectively. Conclusion: Worker-occupation fit has a mediating effect between occupational stress and anxiety symptoms in medical staff, but mainly direct effect.

[Literature analysis of hot topics on occupational noise-induced hearing loss]

Objective: To analyze the literature of related research reports on occupational hearing loss (ONIHL) , study the characteristics of the subject and determine the research hotspots. Methods: In December 2020, PubMed database was searched by bibliometrics for ONIHL published in PubMed database from January 1971 to December 2020. Bicomb 2.03 software was used to extract the subject. The publication year, publication country, source magazine and subject words were summarized and analyzed. Results: A total of 1 473 papers were included in this study, and the number of papers was 66 from 1971 to 1980, and 628 from 2011 to 2020, an increase of nearly 10 times. The top three countries were the United States, China and Germany, with 31.5% (464/1473) , 11.5% (171/1473) and 6.2% (91/1473) ; The cross-sectional study was the most applied type; The top five words for 2011-2020: Mental Illness, polymorphism, cardiovascular disease, high frequency hearing impairment and standards and regulations. Conclusion: Susceptibility Genes, Psychological Disorders, Cardiovascular Diseases and Risk Assessment are hot areas in ONIHL at present. Researchers should focus on major fields and grasp future trends as a whole.

[The influence of subjective comfort of working environment on occupational stress of railway station workers]

Objective: To explore the influential factors of job stress suffered by workers in railway stations, the level of job stress of were measured and subjective comfort of employees targeting to working environment were reported. Methods: In March 2019, a cluster sampling study was designed to collect the personal characteristics, job characteristics and subjective comfort degree of working environment of 432 employees in Chongqing railway stations. Meanwhile, job stress was assessed using the effort-reward imbalance scale. Chi-square test was used to compare the difference of occupational stress detection rate among different stratified factors such as occupational characteristics. Logistic regression was applied to analyze the influential factors of occupational stress. Results: The detection rate of job stress of workers in the railway stations was 31.02% (134/432) . The detection rate of job stress was higher among the divorced workers in railway stations, those earning less than 5, 000 yuan per month, those with 10-20 years' length of service, those who worked as a conductor and other workers including baggageman, station master on duty and assistant engineer (χ(2)=9.61, 14.76, 23.28, 11.06, P=0.008, 0.002, 0.000, 0.011) . The detection rate of job stress was higher among those whose working environment subjective feelings were uncomfortable, the differences were statistically significant (P<0.001) . The results showed that the occupational stress of the staff in the railway stations was influenced by their subjective feeling of air quality, noise and Space Layout (P<0.05) . The risk factors of occupational stress were air quality, noise and uncomfortable space layout (OR=0.571, 0.068, 0.441, P=0.051, 0.054, 0.007) . Conductor, other (Bellboy, Duty Station Master, assistant engineer) were the risk factors of occupational stress (OR=1.884, 2.703, P=0.065, 0.019) . The employees of station A and station B were the risk factors of occupational stress (OR=4.681, 1.811, P=0.002, 0.067) . Conclusion: The higher detection rate of job stress of workers in the railway stations is correlated with the subjective comfort degree of the working environment of the workers.

[Endovascular repair of ruptured abdominal aortic aneurysms assisted by double balloon occlusion technique combined with intra-aneurysm fibrin binder injection technique]

Objective: To investigate the long-term efficacy and safety of alternating double balloon occlusion combined with intra-aneurysm injection of human fibrin binder in the endovascular repair of ruptured abdominal aortic aneurysm (rAAA). Methods: The clinical data of 28 patients with rAAA admitted to Department of Vascular Surgery, the Fourth Affiliated Hospital of Guangxi Medical University from January 2015 to December 2019 were retrospectively analyzed. There were 23 males and 5 females, aged (62±5) years (range: 46 to 88 years).The maximum diameter of the tumors was (65.2±10.5) mm (range: 47.3 to 100.5 mm), all of which were subrenal rAAA. The intraoperative EVAR for abdominal aortic aneurysm was successfully performed under the emergency green channel procedure, and this surgery was assisted used the double balloon occlusion technique in aorta of inferior renal and superior renalcombined with intraoperative human fibrin binder injection technique. Observation indexes included: patients with preoperative preparation, operation time, hospitalization days, surgical treatment success rate and the incidence of postoperative complications, and aortic stent form during the follow-up period, the incidence of leakage, branch stents patency rate and infection rates. Results: The preoperative preparation time of 28 patients was (45.5±8.5) minutes (range:20 to 100 minutes). The operation time was (100.0±15.5) minutes (range:85 to 210 minutes), the ICU stay time was (7±2) days(range:1 to 17 days). The length of hospitalization was (13.5±2.5) days(range:5 to 43 days). The success rate of surgical treatment was 92.9% (26/28). Two patients died, 1 case died of postoperative multifocal lacunar cerebral infarction and massive gastrointestinal hemorrhage, and another elderly patient (84 years old) died of massive abdominal fluid due to preoperative abdominal aortic aneurysm rupture, postoperative complicated with significant abdominal compartment syndrome, and secondary multiple organ failure. Balloon occlusion of the upper renal aorta took (13±2)minutes (range:12 to 30 minutes). The intraoperative injection of fibrin adhesive was (14±2) ml(range:6 to 28 ml) in 22 cases. The incidence of major postoperative complications was 57.1% (16/28). Among the 26 patients who survived the surgery, 69.2% (18/26) completed the 3-year follow-up, and the follow-up time was (30±3) months(range:13 to 36 months). During the follow-up, the aortic stent was in good shape without obvious displacement. The incidence of leakage within 6 months after the operation was 10.7% (3/28), and there was no internal leakage in the patients who were followed up for 36 months after the operation. The patency rate of renal artery and iliac artery branch stents was 16/18. The incidence of stent infection was 7.7% (2/26), 1 case occurred at 1 month and another case at 6 months, respectively. All patients recovered after prolonged intensive anti-infection therapy. Conclusions: Under the standard emergency treatment process, the double balloon alternating occlusion technique combined with the intra-aneurysm injection of human fibrin adhesive technique can assist the successful completion of the endovascular repair of rAAA, effectively improve the success rate of treatment for patients, and reduce the incidence of postoperative leakage and serious complications. The mid-term and long-term results of EVAR for rAAA are good, safe and reliable.

[Summary and prospect of early warning models and systems for infectious disease outbreaks]

This paper summarizes the basic principles and models of early warning for infectious disease outbreaks, introduces the early warning systems for infectious disease based on different data sources and their applications, and discusses the application potential of big data and their analysing techniques, which have been studied and used in the prevention and control of COVID-19 pandemic, including internet inquiry, social media, mobile positioning, in the early warning of infectious diseases in order to provide reference for the establishment of an intelligent early warning mechanism and platform for infectious diseases based on multi-source big data.

[Establishment of multi-point trigger and multi-channel surveillance mechanism for intelligent early warning of infectious diseases in China]

This paper reviews the limitations of current infectious disease surveillance and early warning system in China, analyzes the concepts and countermeasures of the establishment of an intelligent early warning platform of infectious diseases based on multi-point trigger mechanism and multi-channel surveillance mechanism and proposes the realization routes for the purpose of facilitating capacity building and improvement of surveillance and early warning of infectious diseases in China.

[The correlation between worker-occupation fit and occupational stress in nurses]

Objective: To explore the relationship between the worker-occupation fit and occupational stress in nurses. Methods: Convenience sampling method was used to collect 1 463 nurses from one general hospital and three specialized hospitals from July to October 2019. Depression-anxiety-stress scale (DASS-21) was used to assess the level of occupational stress. Pearson correlation and multivariate logistic regression model were used to analyze the relationship between the worker-occupation fit and occupational stress. Results: The average age of 1 463 nurses was (31.8±7.2) years, and 92.3% (n=1 350) of nurses were female. 47.2% (n=690) of nurses had occupational stress and the mean score of worker-occupation fit was (34.4±6.1). The worker-occupation fit and occupational stress had a significant negative correlation (r=-0.472, P<0.001). The moderate and high level of the worker-occupation fit, characteristic fit, need supply fit, and demand ability fit had protective effects on occupational stress based on the outcome of multivariate logistic regression model [OR (95%CI) were 0.40 (0.28-0.59), 0.16 (0.10-0.24); 0.32 (0.22-0.47), 0.18 (0.11-0.20); 0.33 (0.21-0.52), 0.18 (0.11-0.30); 0.59 (0.37-0.9), 0.54 (0.38-0.78), respectively]. Conclusion: The worker-occupation fit and different types of fit, including characteristic fit, need supply fit, and demand ability fit, could be associated with the occupational stress.

[The hearing self-protection behavior and internal factors of workers exposured to occupational noise]

Objective: To analyze the hearing self-protection behavior patterns and internal factors of workers exposured to occupational noise in an aircraft manufacturing industry based on health belief model, so as to provide reference for further health promotion programs and intervention measures. Methods: A total of 1600 front-line workers were selected from 10 units of an aircraft manufacturing enterprise by cluster sampling method. The basic and occupational information of employees were collected, and a self-reported questionnaire was designed according to the health belief model to acquire the hearing self-protection behaviors of workers. Results: There were significant differences in the perceived severity, perceived benefit, perceived impairment, self-efficacy and behavioral incentive scores of different hearing self-protection behaviors among the noise-causing workers (P<0.05). There were significant differences in the distribution of hearing self-protection behaviors among different genders, ages, education levels, length of service, initial noise exposure time and cumulative noise reception time (P<0.05). The perceived benefits, perceived barriers, behavioral incentives, self-efficacy scores, and educational attainment of the noise-causing workers were all related to the type of hearing self-protection behavior (P<0.05) . Conclusion: The educational level and health belief model can predict the hearing self-protection behavior patterns of front-line workers to some extent, more attention should be paid to the monitoring of the well-educated employees.

[The inhibition effect of miR-29c on lung fibroblasts transdifferentiation induced by SiO(2)]

Objective: To investigate the regulatory effect of miR-29c on the trans-differentiation of pulmonary fibroblasts into myofibroblasts induced by silica dust. Methods: Fibroblasts obtained from SD rat lung tissue and pulmonary macrophages (NR8383) were co-cultured to establish the silicosis cell model in vitro. And real time-quantitative polymerase chain reaction (RT-qPCR) and Western Blot assays were performed to detect the altered expression level of miR-29c and α-smooth muscle actin (α-SMA) . After that, the in vitro cell model was transfected with corresponding viruses to establish miR-29c overexpression and inhibition cell models, and the mRNA and protein expression levels of α-SMA were detected simultaneously. Results: Compared with control group, the expression level of miR-29c in the silicosis cell model in vitro was down-regulated significantly after 12 or 18 h exposed to SiO(2), and both of the mRNA and protein expression levels of α-SMA were up-regulated instead (P<0.05) . When transfected with corresponding viruses, the mRNA and protein expression levels of α-SMA in the pulmonary fibroblasts were significantly up-regulated in miR-29c inhibition group and down-regulated in miR-29c overexpression group (P<0.05) . Conclusion: Based on the findings, it could be safely infered that the development of pulmonary fibrosis could be impeded by inhibiting transdifferentiation process of pulmonary fibroblasts into myofibroblasts regulated by miR-29c, miR-29c could be an potential therapeutic target to lung fibrosis induced by silica.

[Application of lower abdominal aorta balloon occlusion technique by ultrasound guiding during caesarean section in patients with pernicious placenta previa]

Objective: To discuss the feasibility, effect and safety of lower abdominal aorta balloon occlusion technique by ultrasound guiding during caesarean section in patients with pernicious placenta previa. Methods: The clinical data of 40 patients with pernicious placenta previa complicated with placenta accreta from January 2015 to August 2017 in Liuzhou workers hospital were analyzed retrospectively. The study group included 20 cases, which were operated in the way of cesarean section combined lower abdominal aorta balloon occlusion technique by ultrasound guiding, while the control group also included 20 cases, which were operated in the way of the conventional cesarean section without balloon occlusion technique. The bleeding amount, blood transfusion volume, operative total time, hysterectomy and complications of the two groups were compared. Results: The bleeding amount and blood transfusion volume in study group were(850±100)ml and (400±50)ml, which were lower than that of the control group[(2 500±230)ml and (1 500±100)ml], the difference was statistically significant(t=35.624, 16.523, all P<0.05). In addition, the hysterectomy rate in study group was 5%, which was lower than that in the control group(30%), the difference was statistically significant(χ²=8.672, P<0.05). And the total time of operation was (2.0±0.5)h in the study group, which was shorter than that in the control group[(3.5±0.4)h]. The difference was statistically significant(t=11.362, P<0.05). No postoperative complications took place in the study group.The blood pressure, heart rate and blood oxygen fluctuated significantly, and the postoperative renal function was significantly reduced in the control group. Conclusions: The lower abdominal aorta balloon occlusion technique by ultrasound guiding during a caesarean section in patients with pernicious placenta previa can effectively control the bleeding during operation, and preserve reproductive function to the utmost degree.Therefore, the technique is safe, feasible, convenient and cheaper, and worthy of being widely applied in clinic.

[Effects of Personality and Psychological Acceptance on Medical Workers' Occupational Stress]

Objective: To assess psychological acceptance and occupational stress of medical staff, analyze the relationship among personality, psychological acceptance and occupational stress and discuss the direct or indirect effects of personality to occupational stress. Methods: Eysenck Personality Questionnaire (EPQ-RSC) , Acceptance and Action Questionnaire-II (AAQ-Ⅱ) and Revised Occupational Stress Inventory (OSI-R) were administered to 749 medical staff. Results: The level of occupational stress of medical staff was high, the score of PSY was 26.8±7.13 and the score of PHS was 24.3±6.50. Personality and psychological acceptance can predict occupational stress. Psychological acceptance was a protective factor of occupational stress. Medical staff with personality of introversion, neuroticism and psychoticism suffered higher occupational stress. Personality have both direct and indirect effects on occupational stress. Neuroticism have the strongest effect on occupational stress with effect size of 0.496 (psychological stress) and 0.431 (physical strain) . Conclusion: Medical staff have heavier occupational stress. There is a significant correlation between personality and occupational stress. Measures depending on personality should be taken to deal with this situation.

[Relationship between occupational stress, recovery experience, and physiological health of nurses in a municipal grade A tertiary hospital]

Objective: To examine the relationship between recovery experience, occupational stress, and physiological health of nurses in a municipal grade A tertiary hospital. Methods: A total of 296 in-service nurses from 7 municipal grade A tertiary hospitals were selected from October 2015 to February 2016. Individual characteristics of the subjects were collected using a self-made questionnaire. The recovery experience, occupational stress, and physiological health of the subjects were assessed based on the physiological health dimensions in the Chinese version of Recovery Experience Questionnaire (REQ-C) , Job Content Questionnaire (JCQ) , and Quality of Work Life (QWL7-32) . Results: The mean recovery experience score of nurses from the municipal grade A tertiary hospital was 45.04±7.72, and 51.35% of the nurses had satisfactory recovery experience. Occupational stress was identified in 81.76% of the nurses. Based on the four categories of occupational stress, 65 nurses were identified with high-strain jobs (21.95%) , 56 with relaxed (low-strain) jobs (18.92%) , 49 with passive jobs (16.55%) , and 126 with active jobs (42.57%) . In addition, the mean physiological health score of the nurses was 21.20±4.24. Physiological health was negatively correlated with occupational stress (r=-0.173, P<0.05) , but positively correlated with recovery experience (r=0.198, P<0.01) . Recovery experience was negatively correlated with occupational stress (r=-0.116, P<0.05) . Job demand was the major contributor to occupational stress, where subjects with high-demand active jobs had the poorest recovery experience (F=2.610, P<0.05) and physiological health (F=8.166, P<0.01) . Conclusion: Job demand has a great impact on the occupational stress of nurses, where increased job demand can lead to stronger stress response, reduced recovery experience, and poorer physiological health.

[Effect of vanadium exposure on neurobehavioral function in workers]

OBJECTIVE

To establish the comprehensive indicators for neurobehavioral function test, and to investigate the possible adverse effect of long-time vanadium exposure on neurobehavioral function and its features in workers.

METHODS

From July to November, 2012, The Neurobehavioral Core Test Battery(NCTB) recommended by WHO was used to conduct tests for 128 workers in vanadium exposure group and 128 workers in control group. The t-test and analysis of covariance were used to compare the differences in each indicator in NCTB between different populations, and the principal component analysis was used to establish the comprehensive neurobehavioral index(NBI) and investigate the effect of vanadium on workers' neurobehavioral function.

RESULTS

The vanadium exposure group had significantly lower visual retention score(6.9±1.9), digit span(order) score(8.9±2.9), lifting and turning dexterity(the non-handed hand) score (14.1±3.6), pursuit aiming test(the number of correct dots) score(65.7±24.8), and digit symbol score (31.1±15.0) than the control group (8.2±1.3, 9.4±2.7, 15.5±3.0, 76.5±23.8, and 33.7±9.5)(all P<0.05). The vanadium exposure group also had a significantly lower NBI than the control group(-0.167±0.602 vs 0.168±0.564, P<0.05).

CONCLUSION

Long-term vanadium exposure can influence the workers' neurobehavioral function, with the manifestations of decreased hearing and visual memory, movement velocity, accuracy, and coordination.

[Relationship of job stress with job burnout and quality of work life in workers for offshore oil platforms]

Objective: To evaluate the current status of job burnout and qual ity of work life (QWL) in workers for offshore oil platforms, and to analyze the relationship of job stress with job burnout and QWL and the direct and indirect effects of job stress on QWL. Methods: Cluster random sampling was used to select 382 work-ers for 8 oil platforms of China National Offshore Oil Corporation in October 2015. A self-designed questionnaire was used to collect the individual characteristics of subjects. The Quality of Work Life Scale (QWL7-32) , Occupa-tional Stress Inventory-Revised Edition (OSI-R) , and Maslach Burnout Inventory-General Survey (MBI-GS) were used to investigate the QWL, job stress, and job burnout of subjects. Results: Among all the workers for offshore oil platforms, 87.2% had mild job burnout. The total QWL score was 116.01 ± 16.73; 8.3% of the workers had poor QWL, and 68.5% had moderate QWL. QWL was reduced with heavier task, vaguer task, and increasing mental stress and physical stress (P<0.05) , and increased with more social support (P<0.05) . Job stress had di-rect and indirect effects on QWL; stress reaction had the most effect on QWL (total effect size -0.509) , followed by social support (total effect size 0.444) . Conclusion: Most workers for offshore oil platforms have mild job burn-out and moderate QWL. Job stress is associated with job burnout and QWL, and stress reaction and social support have relatively high influence on QWL.

Timing of gangrene tissue debridement after autologous bone marrow cell implantation in patients with superficial femoral arterial occlusion: preliminary experiences

AIM

Although implantation of bone marrow mononuclear cells (BMI) was shown to improve outcomes in patients with severe peripheral arterial occlusive disease (PAOD), little experience has been reported in patients with an arterial occlusion level above the knee, ischemic gangrene, and high cardiovascular risk. This study sought to investigate the timing of gangrene tissue debridement and the safety of BMI in these patients.

METHODS

Six "no-option" PAOD patients were enrolled with an arterial occlusion level above the knee, ischemic gangrene, and 3 systemic diseases related to a high cardiovascular risk. The ischemic status was evaluated by measuring the ankle-brachial index (ABI), transcutaneous oxygen pressure (TcPO2), and wound healing after BMI.

RESULTS

All patients safely underwent the procedures with intravenous general anesthesia by titrating propofol. Major lower extremity amputation, minor debridement amputation, and debridement surgery were performed in 2 (33.3%), 1 (16.7%), and 2 (33.3%) patients, respectively, 3.1 2.8 months after BMI. Compared to the amputation group (N=3), the salvage group (N=3) had a significantly higher baseline ABI (P=0.02) and a shorter distance between the gangrene site and arterial occlusion site (P=0.01). In the 3 patients who underwent debridement, ABI and TcPO2 significantly improved 1 month after BMI, and gangrenous tissues were debrided 3.8 ± 3.6 (range, 1~8) months after BMI with complete healing within 1 month.

CONCLUSION

Autologous BMI therapy is safe in patients at high cardiovascular risk with an arterial occlusion level above the knee and ischemic gangrene. Effective predictors of BMI include the baseline ABI and distance to the ischemia. Gangrene tissue should be debrided at least 1 month after BMI.

Cancer mortality among Chinese chrysotile asbestos textile workers

To determine mortality associated with exposure to chrysotile asbestos, a cohort of asbestos workers from an asbestos textile factory in China was followed prospectively from 1972 to 2008. A total 577 workers were successfully followed, achieving a follow-up rate of 98.5% over 37 years. Employment data and smoking information were obtained from factory and individual workers. Vital status was ascertained from factory personnel records and the municipal death registry. Workers were categorized into high, medium and low exposure groups in terms of their job titles and workshops. Follow-up generated 17,508 person-years, with 259 deaths from all causes, 96 all cancers and 53 lung cancers and 2 mesotheliomas. The highest cancer mortality was observed in the high exposure group, with 1.5-fold age-adjusted mortality from all cancers and 2-fold from lung cancer compared to the low exposure group. Age and smoking adjusted hazard ratio in the high exposure group was 2.99 (95%CI, 1.30, 6.91) for lung cancer and 2.04 (1.12, 3.71) for all cancers. Both smokers and nonsmokers at the high exposure level had a high death risk of lung cancer, with a clearer exposure-response trend seen in smokers. This study confirmed increased mortality from lung cancer and all cancers in asbestos workers, and the cancer mortality was associated with exposure level.

[Protective effects of recombinant SCR15-18 domain of human soluble complement receptor type 1 on myocardial ischemia and reperfusion injury]

OBJECTIVE

To investigate the protective effects of recombinant SCR15-18 domain of human soluble complement receptor type 1 (sCR1-SCR-15-18) in rats underwent myocardial ischemia and reperfusion (I/R).

METHODS

Sprague-Dawley rats were randomly divided into three groups (n = 12 each group): sham (SO); 30 min ischemia/3h reperfusion (I/R) and I/R plus sCR1-SCR15-18 (15 mg/kg before I/R, sCR1). Serum LDH, CK and cardiac myeloperoxidase (MPO) activity were measured. Infarct size, myocardial histopathological changes and myocardial C3c were also compared among groups.

RESULTS

Infarct size [(16.1 +/- 3.3)% vs. (22.9 +/- 3.0)%, infarct zone/left ventricular mass, P < 0. 05] and CK [(2532.5 +/- 597.1) U/L vs. (3400.9 +/- 534.9) U/L, P < 0. 05] and LDH [(5436.2 +/- 611.3) U/L vs. (6572.0 +/- 476.3) U/L, P < 0. 05] as well as MPO activity in infarct zone [(0.81 +/- 0.14) U/g vs. (1.12 +/- 0.13) U/g, P < 0.05] were significantly decreased post sCR1 compared to I/R group. sCR1 also significantly attenuated histological myocardial injury and reduced the deposition of C3c in infarct zone.

CONCLUSION

sCR1-SCR15-18 protein exerts cardioprotective effects in this rat I/R model.

Cancer mortality among workers exposed to amphibole-free chrysotile asbestos

The issue of whether exposure to chrysotile asbestos alone, without contamination from amphibole asbestos, causes lung cancer and mesothelioma was investigated in a 25-year longitudinal study (1972-1996) in Chongqin, China. The study cohort comprised 515 male asbestos plant workers exposed to chrysotile only; the control cohort included 650 non-dust-exposed workers. The results of analysis in which the proportional hazards model was used indicated that mortality due to all causes, all cancers, and lung cancer was related to asbestos exposure; the relative risks, adjusted for age and smoking, were 2.9, 4.3, and 6.6, respectively. Fiber concentrations in the raw material section and the textile section of the plant were 7.6 and 4.5 fibers/ml, respectively. Because of differences between the study and control plants, the authors also compared various sections of the asbestos plant that had different levels of dust exposure. The adjusted relative risk of lung cancer was 8.1 for workers exposed to high versus low levels of asbestos. Two cases of malignant mesothelioma, one pleural and the other peritoneal, were found in the asbestos cohort. These results suggest that heavy exposure to pure chrysotile asbestos alone, with negligible amphibole contamination, can cause lung cancer and malignant mesothelioma in exposed workers.

Multiple lymphomatous polyposis of the gut: case report

Multiple lymphomatous polyposis (MLP) is an uncommon type of primary non-Hodgkin's gastrointestinal B-cell lymphoma characterized by the presence of multiple lymphomatous polyps along the gut. We present a patient with MLP in which the involvement was unusually widespread. The diagnosis was confirmed by the typical polyposis lesion, histology, phenotyping and clinical presentations. A 68-year-old man had a large mass at the ileocecal valve as well as multiple polyps along the whole digestive tract. At the time of diagnosis, lymphoma had involved bone marrow, peripheral blood, spleen, prostate and peripheral lymph nodes. The patient received 8 courses of chemotherapy with no remission. He died of pneumonia 11 months after diagnosis. Clinically, the diagnosis may be confused with epithelial polyps; and histologically, the diagnosis must be distinguished from benign lymphoid proliferations as well as other types of lymphoma. The prognosis for patients with MLP is relatively poor (the median survival is usually less than 3 years).

Plasmacytoid lymphocytic lymphoma presenting with IgG hyperviscosity syndrome and peritoneal lymphomatosis

We reported a 74-year-old woman with plasmacytoid lymphocytic lymphoma who initially presented with exertional dyspnea, conscious disturbance, ascites, and lytic skull lesions. Protein electrophoresis and immunoelectrophoresis showed monoclonal IgG-lambda gammopathy with IgG level of 13300 mg/dl and marked suppression of the residual normal immunoglobulins. Abdominal computed tomography (CT) revealed a pattern mimicked cancerous peritonitis. She responded to plasmapheresis with much clinical improvement of the hyperviscosity syndrome but died of H. influenza sepsis 3 weeks after diagnosis. The unusual and interesting features of this case included: (1) IgG hyperviscosity syndrome and diffuse peritoneal involvement as the initial manifestations in plasmacytoid lymphocytic lymphoma, and (2) presence of lytic bone lesions in conjunction with high level of M--component and marked suppression of normal residual immunoglobulins in a patient with lymphoma rather than multiple myeloma.