[Study on the molecular mechanism of autophagy and apoptosis induced by ultrafine carbon black in human bronchial epithelial cells and the intervention effect of N-acetylcysteine].

Objective: To investigate the molecular mechanism of autophagy and apoptosis induced by ultrafine carbon black in human bronchial epithelial cells (BEAS-2B cells), and to study the intervention effect and mechanism of N-acetylcysteine (NAC) on ultrafine carbon black-induced oxidative damage in BEAS-2B cells. Methods: In March 2023, BEAS-2B cells were used as research object, an in vitro airway model exposed to ultrafine carbon black was constructed. A control group and three carbon black exposure groups (50, 100, 200 µg/ml) were set up, and the cells were treated with corresponding concentrations of ultrafine carbon black for 24 hours. In addition, the experiment was divided into control group, NAC+ control group, 100 µg/ml carbon black exposure group and NAC+ exposure group. The corresponding groups were treated with 2 mmol/L NAC for 1 h and 100 µg/ml ultrafine carbon black for 24 h, respectively. Cell viability was measured by CCK-8 assay. Intracellular reactive oxygen species (ROS) level was detected by chemical fluorescence method. The activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT), as well as the content of malondialdehyde (MDA) were detected by colorimetry. The mRNA and protein expressions of autophagy-related genes[Atg5, Atg7, Beclin1, microtubule-associated protein light chain 3B (LC3B), p62 and lysosome-associated membrane protein 2 (LAMP2) ] and apoptosis-related genes [B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), Caspase3, Caspase9 and poly (ADP-ribose) polymerase 1 (PARP1) ] were determined by fluorescence quantitative PCR and Western blot. Cell apoptosis was determined by flow cytometry. Results: Compared with the control group, the relative survival rates of BEAS-2B cells in 50, 100, 200 µg/ml carbon black exposure groups were significantly decreased, the levels of ROS and MDA were significantly increased, and the activities of SOD, GSH-Px and CAT were significantly decreased (P<0.05). The relative survival rate, ROS and MDA levels, SOD, GSH-Px and CAT activities were significantly correlated with the exposure dose of ultrafine carbon black (r(s)=-0.755, 0.826, 0.934, -0.810, -0.880, -0.840, P<0.05). Compared with the control group, the relative expression levels of Atg5, Atg7, Beclin1, LC3B, p62, LAMP2, Bax, Caspase3, Caspase9, PARP1 mRNA and Atg5, Atg7, Beclin1, LC3BⅡ, p62, LAMP2, Bax, cleaved Caspase3 (C-Caspase3), cleaved Caspase9 (C-Caspase9), cleaved PARP1 (C-PARP1) protein and the ratio of LC3BⅡ/LC3BⅠ in 50, 100 and 200 µg/ml carbon black exposure groups were significantly increased, while the relative expression levels of Bcl-2 mRNA and protein were significantly decreased (P<0.05). The changes of the above indexes were significantly correlated with the exposure dose of carbon black (r(s)=0.892, 0.879, 0.944, 0.892, 0.828, 0.880, 0.814, 0.794, 0.931, 0.918, 0.813, 0.866, 0.774, 0.695, 0.918, 0.761, 0.794, 0.944, 0.833, 0.866, 0.905, -0.886, -0.748, P<0.05). Compared with 100 µg/ml carbon black exposure group, the relative survival rate, the activities of SOD, GSH-Px and CAT in NAC+exposure group were significantly increased, while the levels of ROS and MDA were significantly decreased, and the relative expression levels of LC3B, p62 and Caspase3 mRNA and protein as well as the ratio of LC3BⅡ/LC3BⅠ were significantly decreased, and the differences were statistically significant (P<0.05). Compared with the control group, the apoptosis rates of BEAS-2B cells in 50, 100, 200 µg/ml carbon black exposure groups were significantly increased (P<0.05), and there was a significant positive correlation between ultrafine carbon black exposure dose and cell apoptosis rate (r(s)=0.944, P<0.05). While compared with 100 µg/ml carbon black exposure group, the apoptosis rate of NAC+exposure group was significantly decreased, and the difference was statistically significant (P<0.05) . Conclusion: Cell autophagy and apoptosis may be important pathophysiological mechanisms of ultrafine carbon black-induced oxidative damage in BEAS-2B cells. NAC can alleviate the occurrence of BEAS-2B cell damage caused by ultrafine carbon black by regulating oxidative stress and the cascading autophagy and apoptosis pathways.

[Diagnostic value of apparent diffusion coefficient histograms using multiplexed sensitivity encoding diffusion-weighted imaging for distinguishing nasopharyngeal carcinoma from benign hyperplasia].

The data of 115 patients with nasopharyngeal masses (78 males and 37 females) aged between 12 and 78 years at the Sun Yat-sen University Cancer Center from May 2022 to July 2023 were retrospectively reviewed, including 70 cases of nasopharyngeal carcinoma and 45 cases of benign hyperplasia. The mean, median, and percentiles (10th, 25th, 75th, and 90th) of the apparent diffusion coefficient (ADC) histogram derived from multiplexed sensitivity encoding diffusion-weighted imaging (MUSE-DWI) of the benign hyperplasia group were significantly higher than those of the nasopharyngeal carcinoma group (all P<0.05). Conversely, the kurtosis and skewness of benign hyperplasia group were significantly lower than those of the nasopharyngeal carcinoma group (both P<0.05). The area under receiver operating characteristic (ROC) curve of the combined ADC histogram parameters was 0.812 (95%CI: 0.732-0.892), and the sensitivity, specificity and accuracy were 92.86%, 57.78% and 79.13%, respectively. The current study indicates ADC histogram parameters derived MUSE-DWI exhibit significant discriminatory value between nasopharyngeal carcinoma and benign hyperplasia.

Signatures of a magnetic-field-induced Lifshitz transition in the ultra-quantum limit of the topological semimetal ZrTe5.

The quantum limit (QL) of an electron liquid, realised at strong magnetic fields, has long been proposed to host a wealth of strongly correlated states of matter. Electronic states in the QL are, for example, quasi-one dimensional (1D), which implies perfectly nested Fermi surfaces prone to instabilities. Whereas the QL typically requires unreachably strong magnetic fields, the topological semimetal ZrTe5 has been shown to reach the QL at fields of only a few Tesla. Here, we characterize the QL of ZrTe5 at fields up to 64 T by a combination of electrical-transport and ultrasound measurements. We find that the Zeeman effect in ZrTe5 enables an efficient tuning of the 1D Landau band structure with magnetic field. This results in a Lifshitz transition to a 1D Weyl regime in which perfect charge neutrality can be achieved. Since no instability-driven phase transitions destabilise the 1D electron liquid for the investigated field strengths and temperatures, our analysis establishes ZrTe5 as a thoroughly understood platform for potentially inducing more exotic interaction-driven phases at lower temperatures.

[Analysis of change in esophageal varices and clinical characteristics in hepatitis B virus-related cirrhosis after antiviral therapy].

Objective: To clarify the effect and related factors of antiviral therapy on the change of esophageal varices in patients with hepatitis B virus-related cirrhosis. Methods: Fifty-two cases with hepatitis B virus-related cirrhosis who underwent endoscopy before and after antiviral therapy were selected from prospective cohorts. Patients were divided into three groups: no, mild, and moderate-severe based on the degree of esophageal varices. The changes in the severity of esophageal varices in each group were compared after antiviral therapy. Clinical characteristics (platelet, liver and kidney function, liver stiffness, and virological response) of patients with different regressions were analyzed. Measurement data were analyzed by independent sample t-test, one-way ANOVA, Mann-Whitney U test and Kruskal-Wallis H test, and Chi-Square test was used for count data. Results: All patients received entecavir-based antiviral therapy. The median treatment time was 3.1 (2.5-4.4) years. The proportion of patients without esophageal varices increased from 30.8% to 51.9%, the proportion of mild esophageal varices decreased from 40.4% to 30.8%, and the proportion of patients with moderate-to-severe esophageal varices decreased from 28.8% to 17.3% (χ2=14.067, P=0.001). A total of 40.4% of patients had esophageal varices regression, and 13.5% had esophageal varices progression. The progression rate was significantly higher in patients with moderate-severe esophageal varices than patients with mild and no esophageal varices (χ2=28.126, P<0.001), and 60.0% of patients with moderate-severe esophageal varices still remained in moderate-severe state after antiviral treatment. Baseline platelet count and 5-year mean change rates were significantly lower in patients with progressive moderate-to-severe esophageal varices than in those without progression (+3.3% vs. +34.1%, Z=7.00, P=0.027). Conclusion: After effective antiviral treatment, 40.4% of patients with hepatitis B virus-related cirrhosis combined with esophageal varices has obtained esophageal varices regression, but those with moderate to severe esophageal varices still have a considerable risk of progression while receiving mono antiviral treatment only. Thrombocytopenia and without significant improving are the clinical signs of progression risk after receiving antiviral treatment.

[Histological regression and clinical benefits in patients with liver cirrhosis after long-term anti-HBV treatment].

Objective: Our study aims to determine histological regression and clinical improvement after long-term antiviral therapy in hepatitis B virus-related cirrhosis patients. Methods: Treatment-naïve chronic hepatitis B patients with histologically or clinically diagnosed liver cirrhosis were enrolled. Liver biopsies were performed after 5 years entecavir-based antiviral treatment. Patients were followed up every 6 months. Cirrhosis regression was evaluated based on Metavir system and P-I-R score. Clinical improvement was evaluated before and after the long-term treatment. Kruskal Wallis test and Wilcoxon signed-rank test were used for continuous variables, Fisher's exact test was used for categorical variables and multivariate analysis was performed using logistic regression analysis. Results: Totals of 73 patients with HBV-related liver cirrhosis were enrolled. Among them, 30 (41.1%) patients were biopsy proved liver cirrhosis and the remaining 43 (58.9%) cirrhotic patients were diagnosed by clinical features. Based on Metavir system and P-I-R score, 72.6% (53/73) patients attained histological regression. Furthermore, 30.1% (22/73) were defined as significant regression (Metavir decrease ≥2 stage), 42.5% (31/73) were mild regression (Metavir decrease 1 stage or predominantly regressive by P-I-R system if still cirrhosis after treatment) and 27.4% (20/73) were the non-regression. Compared to levels of clinical characteristics at baseline, HBV DNA, ALT, AST, liver stiffness(decreased from 12.7 to 6.4 kPa in significant regression, from 18.1 to 7.3 kPa in mild regression and from 21.4 to 11.2 kPa in non-regression)and Ishak-HAI score significantly decreased after 5 years of anti-HBV treatment, while serum levels of platelets and albumin improved remarkably (P<0.05). In multivariate analysis, only the pre-treatment liver stiffness level was associated with significant regression (OR=0.887, 95%CI: 0.802-0.981, P=0.020). Conclusions: After long-term antiviral therapy, patients with HBV-related cirrhosis are easily to attain improvements in clinical parameters, while a certain percentage of these patients still cannot achieve histological reversal.

[Self-awareness rate and its influencing factors of their infection status among hepatitis B surface antigen-positive persons aged 15-69 years in China].

Objectives: To understand the awareness rate and its influencing factors of their HBV infection status among HBsAg-positive persons aged 15-69 years in China. Methods: A cross-sectional design was used to conduct a questionnaire survey on the awareness of their infection status among HBsAg-positive persons aged 15-69 years who were identified in the 2020 national hepatitis B seroepidemiology survey. The awareness rate of the whole respondent and respondents with different characteristics were described, and the differences were compared with the χ2 test. The logistic regression model was used to analyze the factors influencing the awareness rate. Results: The overall awareness rate among the respondents was 43.10% (1 828/4 241). The awareness rate was lower in males than in females (41.30% vs. 44.65%). The awareness rate was lower in the 60-69-years-old age group than in other age groups (30.38% vs. 36.77%-57.58%). The awareness rate was lower in rural areas than in urban areas (39.43% vs. 47.32%). The awareness rate was lower in regions with a per capita gross domestic product (GDP) below RMB 54 000 than in regions with a per capita GDP of RMB 54 000 and above (36.81% vs. 41.61%-50.30%). The awareness rate was lower in respondents without other liver diseases than with other liver diseases (41.52% vs. 60.68%). The awareness rate was lower in respondents without a family history of hepatitis B-related disease or unknown family history than with a family history (43.58% vs. 68.26%; 24.71% vs. 68.26%). Multivariate logistic regression analysis showed that male [odds ratio (OR)=0.841, 95% confidence interval (CI): 0.734-0.964], high school and below [primary school and below, junior middle school, high school/technical secondary school, OR (95%CI): 0.247 (0.190-0.321), 0.451 (0.352-0.577), 0.634 (0.486-0.827)], rural areas (OR=0.822, 95%CI: 0.715-0.945) and regions with a per capita GDP below RMB 80 000 [54 000-80 000, OR (95%CI): 0.810 (0.688-0.954), below RMB 54 000, OR (95%CI): 0.793 (0.669-0.941)] were the negative factors influencing the awareness rate. While 30-39-years-old (OR=2.089, 95%CI: 1.626-2.683) and 40-49-years-old (OR=1.590, 95%CI: 1.250-2.023) age groups, with other liver diseases (OR=2.244, 95%CI: 1.754-2.871) and family history related to hepatitis B (OR=2.688, 95%CI: 2.242-3.223) were the positive factors influencing the awareness rate. Conclusion: The overall awareness rate of their infection status among HBsAg-positive persons aged 15-69 years is 43.10% in China. Health promotion and coverage expansion on HBV screening should be further strengthened to achieve the proposed World Health Organization's target of 90% HBV infection diagnosis rate by 2030.

Primary highly differentiated breast angiosarcoma in an adolescent girl.

Primary angiosarcoma of the breast is very rare. Surgery is the principal mode of treatment for primary angiosarcoma of the breast and generally consists of a total mastectomy. To discuss its etiology and treatment principles, we reported a case of primary mammary angiosarcoma in an adolescent girl. The patient had been treated in other hospitals several times due to erythema of the breast as inflammatory treatment was considered, until pathological nature was determined after we performed pathological needle puncture. The case discussed here is unique in its own way, having clinical imaging and pathological features of primary angiosarcoma in an adolescent girl and it is known that primary angiosarcoma is unusual for this age group.

Promoting effect of the recombinant resuscitation promoting factors-2 of Rhodococcus erythropolis on petroleum degradation and cultivable bacterial diversities of the oil-contaminated soils.

Resuscitation-promoting factors (Rpfs) belong to peptidoglycan hydrolases, which participate in recovery of dormant cells and promoting bacteria growth. In this study, the resuscitation promoting factor rpf2 gene of Rhodococcus erythropolis KB1 was expressed in Escherichia coli and purified by Ni2+ affinity chromatography. The purified recombinant fusion protein Rpf2 showed a closely 50 kDa band on sodium dodecyl sulphate polyacrylamide gel electrophoresis. The protein showed muralytic activity, with a specific activity of 1503 ± 123 U mg-1 when determined with 4-methylumbelliferyl-ß-d-N, N',N″-triacetotri-ylchitoside as substrate. It also showed protease activity when measured with azocasein as substrate, with a specific activity of 1528 ± 411 U mg-1 . The addition of the recombinant Rpf2 protein significantly increased petroleum degradation efficiency of the indigenous micro-organisms and the petroleum degradation rates increased from 30·86 to 43·45%, 45·20 and 49·23% in the treatment groups. The recombinant protein also increased the petroleum-degrading bacterial diversities enriched from the contaminated soils. The cultivable bacterial flora of the treatment groups supplemented with different concentrations of Rpf2 increased from 82 genera in 9 phyla to 116 genera in 16 phyla and 138 genera in 16 phyla respectively. Thirteen extra petroleum-degrading bacteria strains were isolated from the petroleum-contaminated soils in the groups containing the recombinant Rpf2.

Accuracy of intentionally tilted implant placement in the maxilla using dynamic navigation: a retrospective clinical analysis.

The aim of this retrospective study was to investigate the accuracy of dynamic navigation for the placement of intentionally tilted implants in the posterior maxilla. The study included 12 patients with edentulism or continuous multiple tooth loss, who had 48 implants inserted under dynamic navigation guidance in the posterior maxilla. Twenty-four implants near maxillary sinuses were intentionally tilted. The average platform deviation was 1.3 ± 0.4 mm (range 0.8-2.3 mm), apex deviation was 1.1 ± 0.5 mm (range 0.2-2.3 mm), and axis deviation was 3.1 ± 1.0° (range 1.8-6.7°). The other 24 implants were axially positioned. The average platform deviation was 1.5 ± 0.5 mm (range 0.7-3.1 mm), apex deviation was 1.3 ± 0.7 mm (range 0.5-3.1 mm), and axis deviation was 3.2 ± 1.5° (range 1.5-7.7°). There was no significant difference in platform deviation, apex deviation, or axis deviation between the tilted implants and implants in the axial position (P > 0.05). This analysis indicates that a dynamic navigation system can be used as a method of guidance to place intentionally tilted implants as accurately as axially positioned implants in the posterior maxilla, thereby preventing damage to the maxillary sinuses and the need to graft bone.

[Analysis on hepatitis B cases reported from surveillance points in China, 2019].

Objective: To understand the characteristics of hepatitis B cases reported through the National Notifiable Disease Reported System (NNDRS) of China in 2019, analyze the quality of hepatitis B reporting. Methods: The survey forms and reporting cards of hepatitis B cases in 200 surveillance points in China in 2019 were collected from NNDRS, the completeness rate of the reporting card was calculated, and the reported hepatitis B cases were verified based on the diagnostic criteria (WS 299-2008). The clinical types of the cases after verification were compared with the reported ones, the consistency was evaluated with Kappa test. The reasons for the inconsistent clinical types of the cases were analyzed. Results: In 2019, a total of 64 686 hepatitis B cases were reported through NNDRS. Acute, chronic and unclassified hepatitis B cases accounted for 5.8%, 92.4% and 1.8%, respectively. The average age of reported cases was 47 (47±15) years, and males accounted for 64.4%. The average level of alanine aminotransferase was 214.2 (214.2±1 253.4) U/L. The reported cases mainly worked in agriculture, forestry, animal husbandry, fishery, and water conservancy (50.6%, 32 722). The proportions of cases reported from the eastern, western and central regions were 42.5% (27 501),22.1% (14 315) and 35.4% (22 870), respectively. The consistent rate of the clinical types between the reported cases and the verified cases was 58.8%, with a Kappa value of 0.15. For the 39 271 cases confirmed as acute and chronic hepatitis B cases in the reporting cards, the consistent rate of the clinical types between the reported cases and the verified cases was 96.9%, with a Kappa value of 0.73. In 94.5% (24 267/25 681) of the cases with inconsistent clinical types, the reporting card information were incomplete. Conclusion: The diagnosis of hepatitis B has been improved in the hepatitis B surveillance in China, but it is necessary to improve the completeness of the reporting cards of hepatitis B cases to NNDRS.

Origin of the quasi-quantized Hall effect in ZrTe5.

The quantum Hall effect (QHE) is traditionally considered to be a purely two-dimensional (2D) phenomenon. Recently, however, a three-dimensional (3D) version of the QHE was reported in the Dirac semimetal ZrTe5. It was proposed to arise from a magnetic-field-driven Fermi surface instability, transforming the original 3D electron system into a stack of 2D sheets. Here, we report thermodynamic, spectroscopic, thermoelectric and charge transport measurements on such ZrTe5 samples. The measured properties: magnetization, ultrasound propagation, scanning tunneling spectroscopy, and Raman spectroscopy, show no signatures of a Fermi surface instability, consistent with in-field single crystal X-ray diffraction. Instead, a direct comparison of the experimental data with linear response calculations based on an effective 3D Dirac Hamiltonian suggests that the quasi-quantization of the observed Hall response emerges from the interplay of the intrinsic properties of the ZrTe5 electronic structure and its Dirac-type semi-metallic character.

Relationship between COVID-19 and the male reproductive system.

OBJECTIVE: The objective of this review is to provide currently available information on the potential effects of coronavirus disease 2019 (COVID-19) on male fertility. MATERIALS AND METHODS: This is a mini-review. Due to the similarity between the COVID-19 and severe acute respiratory syndrome (SARS) virus, we searched for the following keywords: "SARS-CoV, male reproductive system, infertility, COVID-19, SARS-CoV-2, and orchitis". By reviewing and analyzing the literature, we analyzed the influence of temperature on sperm, the expression of angiotensin-converting enzyme 2 (ACE2) in the testes, and the impact of SARS-CoV-2 on the male reproductive system. RESULTS: SARS-CoV-2 enters the body through the ACE2 receptor. The high expression of ACE2 on the surface of spermatogonia and supporting cells in the testes, as well as the immune response caused by COVID-19, can lead to testicular spermatogenesis dysfunction and reduced sperm count. CONCLUSIONS: COVID-19 infection can affect male reproductive function, and standard treatment strategies should be established in time to help male patients infected with COVID-19.

Investigation of the feasibility of synthetic MRI in the differential diagnosis of non-keratinising nasopharyngeal carcinoma and benign hyperplasia using different contoured methods for delineation of the region of interest.

AIM: To assess the feasibility and preliminary diagnostic performances of relaxation times derived from synthetic magnetic resonance imaging (syMRI) for differentiating nasopharyngeal carcinoma from nasopharyngeal benign lymphoid hyperplasia, and to assess the influence of tissue segmentation method on relaxation estimates. MATERIALS AND METHODS: Fifty participants with nasopharyngeal carcinoma (NPC) and 40 participants with benign hyperplasia (NPH) who underwent syMRI examination were enrolled prospectively. T1, T2, and proton density (PD) values were obtained from four different regions of interest (ROIs), namely, partial-section, single-section, three-sections, and whole-lesion. The metrics between NPC and NPH or among different ROIs were compared using Student's t-test or one-way ANOVA. The area under curve (AUC) was calculated to assess the performance of metrics obtained from different ROIs to differentiate NPC and NPH. RESULTS: The T1, T2, and PD values for NPH were significantly higher than those for NPC, regardless of the type of ROI used, except for the PD value obtained from the whole-lesion ROI. The T2 values obtained from the single-section ROI showed the highest diagnostic accuracy in distinguishing NPC from NPH, with an AUC of 0.894, sensitivity of 0.900, and specificity of 0.800. Additionally, the T1, T2, and PD values for nasopharyngeal lesions showed no statistical difference among different kinds of ROI, except for the difference in T1 value between partial-section and other methods. CONCLUSION: Quantitative analysis of syMRI has the potential to distinguish NPC from NPH. Moreover, different types of ROI showed limited influence on the relaxation time estimation for nasopharyngeal lesions.

Unconventional Hall response in the quantum limit of HfTe5.

Interacting electrons confined to their lowest Landau level in a high magnetic field can form a variety of correlated states, some of which manifest themselves in a Hall effect. Although such states have been predicted to occur in three-dimensional semimetals, a corresponding Hall response has not yet been experimentally observed. Here, we report the observation of an unconventional Hall response in the quantum limit of the bulk semimetal HfTe5, adjacent to the three-dimensional quantum Hall effect of a single electron band at low magnetic fields. The additional plateau-like feature in the Hall conductivity of the lowest Landau level is accompanied by a Shubnikov-de Haas minimum in the longitudinal electrical resistivity and its magnitude relates as 3/5 to the height of the last plateau of the three-dimensional quantum Hall effect. Our findings are consistent with strong electron-electron interactions, stabilizing an unconventional variant of the Hall effect in a three-dimensional material in the quantum limit.

[Analysis of the relationship between the changes of lung function and serum proinflammatory cytokines in workers occupationally exposed to toluene diisocyanate].

Objective: To analyze the correlation between the changes of lung function and serum proinflammatory cytokines in workers occupationally exposed to toluene diisocyanate (TDI), and to explore the evaluation index of respiratory toxicity of TDI. Methods: In October 2014, 61 male workers engaged in TDI synthesis process, purification process, packaging process and the above production process in a TDI factory in western China were selected as TDI exposure group; 62 male enterprise managers who were not exposed to TDI and other known allergenic chemicals were selected as control group, which were matched at the age of workers in exposure group. The questionnaire survey obtained information such as gender, length of service, age, occupational history, exposed length of service and so on. The lung function indexes [forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), FEV1/FVC] and serum levels of interleukin (IL)-1 ß, IL-6, IL-8, tumor necrosis factor (TNF)-α, macrophage inflammatory factor-1 ß, monocyte chemoattractant factor-1 and vascular endothelial growth factor were measured. The urine was collected after the weekend shift, and the concentration of (TDA), the metabolite of TDI, was determined as the index of internal exposure. Spearman rank correlation was used to analyze the correlation between cytokines and lung function indexes, and multivariate linear regression was used to analyze the changes of lung function indexes and cytokines with TDI exposure concentration and time. Results: The median age (P5-P95) of the exposed group and the control group was 36.5 (24.0-51.0) and 38.0 (24.0-50.0) years, respectively. In the exposed group, the median length of service (P5-P95) was 6.94 (0.97-26.33) years, and the median concentration of TDA in urine was 15.56 (2.28-112.16) ng/ml. The three indexes of lung function, FVC, FEV1, FEV1/FVC and the levels of serum IL-8 and TNF-α were significantly lower than those in the control group (P<0.01). With the increase of exposure concentration and exposure time, the level of serum TNF-α, FVC and FEV1 decreased, and showed a good dose-effect and time-effect relationship (all Ptrend values< 0.05). Serum IL-8 and TNF-α were positively correlated with FVC, FEV1 and FEV1/FVC (all P values<0.01). Conclusion: The levels of serum inflammatory factors IL-8 and TNF-α in worker exposed to TDI are related to lung function indexes, which can be used as early evaluation indexes of respiratory toxicity induced by TDI.

[Study on fibrosis changes in the lungs of mice caused by repeated inhalation of polyhexamethyleneguaidine disinfectant].

Objective: To explore the lung damage caused by repeated inhalation of polyhexamethyleneguanidine (PHMG) disinfectant aerosol and the corresponding toxicological characteristics. Methods: Thirty four-week-old mice of C57BL/6N strain were randomly divided into three groups, the control group, low-dose group, and high-dose group. Each group had 5 male mice and 5 female mice. Lab II-level purified water was used in the control group. The PHMG disinfectant aerosol was generated by using the ultrasonic atomization of the aqueous solution containing PHMG. The PHMG concentrations in the low-and high-dose groups were 0.1 mg/ml (0.01%) and 1 mg/ml (0.1%), respectively. The concentration of PHMG in the post-chemical exposure room was 1.03 mg/m(3) and 9.09 mg/m(3) according to the air sampler analysis. The experimental mice were exposed to the PHMG in dynamic respiratory exposure mode for 4 hours every day in 21 days. After 21-day exposure, bronchia alveolus lung fluids (BALFs) were used to evaluate the inflammatory cells in the lungs, and pathological evaluation, special staining and immunohistochemical methods were further performed to evaluate the key indicators of pulmonary fibrosis. Results: Compared to the control group, the body weight of mice in the high-dose group was significantly decreased (P<0.05), while that of mice in the low-dose group did not significantly differ (P>0.05). The number of inflammatory cells in BALFs of low-dose exposed mice was slightly reduced, and the lung tissue pathology began to show lung damage with early fibrosis symptoms (P<0.05). The pathological examination of mice in the high-dose group showed changes in pulmonary fibrosis. Immunohistochemical staining showed that pulmonary fibrosis marker, α-SMA, was significantly increased in low-dose group and high-dose group (P<0.05). Conclusion: The repeated inhalation of PHMG disinfectant could cause lung damage such as pulmonary fibrosis in mice. It could suggest that special warnings should be given to this common disinfectant and respiratory protection measures should be adopted during industrial production and daily use.

Transcriptomic changes in the nasal epithelium associated with diesel engine exhaust exposure.

BACKGROUND: Diesel engine exhaust (DEE) exposure causes lung cancer, but the molecular mechanisms by which this occurs are not well understood. OBJECTIVES: To assess transcriptomic alterations in nasal epithelium of DEE-exposed factory workers to better understand the cellular and molecular effects of DEE. METHODS: Nasal epithelial brushings were obtained from 41 diesel engine factory workers exposed to relatively high levels of DEE (17.2-105.4 µg/m3), and 38 unexposed workers from factories without DEE exposure. mRNA was profiled for gene expression using Affymetrix microarrays. Linear modeling was used to identify differentially expressed genes associated with DEE exposure and interaction effects with current smoking status. Pathway enrichment among differentially expressed genes was assessed using EnrichR. Gene Set Enrichment Analysis (GSEA) was used to compare gene expression patterns between datasets. RESULTS: 225 genes had expression associated with DEE exposure after adjusting for smoking status (FDR q < 0.25) and were enriched for genes in pathways related to oxidative stress response, cell cycle pathways such as MAPK/ERK, protein modification, and transmembrane transport. Genes up-regulated in DEE-exposed individuals were enriched among the genes most up-regulated by cigarette smoking in a previously reported bronchial airway smoking dataset. We also found that the DEE signature was enriched among the genes most altered in two previous studies of the effects of acute DEE on PBMC gene expression. An exposure-response relationship was demonstrated between air levels of elemental carbon and the first principal component of the DEE signature. CONCLUSIONS: A gene expression signature was identified for workers occupationally exposed to DEE that was altered in an exposure-dependent manner and had some overlap with the effects of smoking and the effects of acute DEE exposure. This is the first study of gene expression in nasal epithelial cells of workers heavily exposed to DEE and provides new insights into the molecular alterations that occur with DEE exposure.

Association between iodine intake and thyroid autoantibodies: a cross-sectional study of 7073 early pregnant women in an iodine-adequate region.

PURPOSE: The association between iodine intake and thyroid autoimmunity has been debated, especially in pregnant women. This study aimed to investigate thyroid autoantibodies and their association with iodine intake and hypothyroidism in early pregnancy. METHODS: 7073 early pregnant women from an iodine-sufficient region participated in this study. Urinary iodine concentrations (UICs) were measured using an ammonium persulfate method. Serum thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TgAb), thyroid-stimulating hormone (TSH), free thyroxine (FT4), and Tg were determined using an electrochemiluminescence immunoassay. RESULTS: Iodine deficiency (UIC < 100 µg/L) was associated with higher risks of TPOAb positivity [adjusted odds ratio (aOR) = 1.64, 95% confidence interval [CI] (1.29-2.08)] and TgAb positivity [aOR = 1.44, 95% CI (1.16-1.80)]. Women with isolated TPOAb positivity, isolated TgAb positivity, or both TPOAb and TgAb positivity had a 14.64-fold, 7.83-fold, and 44.69-fold increased risk of overt hypothyroidism, and a 4.36-fold, 2.86-fold, and 6.26-fold increased risk of subclinical hypothyroidism, respectively. Moreover, the risks of overt and subclinical hypothyroidism in women with a high TPOAb titer were 16.99 and 4.80 times that in TPOAb-negative women, respectively. The risk of overt hypothyroidism in women with a high TgAb titer was 6.97 times that in TgAb-negative women. CONCLUSIONS: Our work demonstrates that iodine deficiency during early pregnancy is an independent risk factor for both TPOAb positivity and TgAb positivity. Furthermore, positivity for both autoantibodies and a high thyroid autoantibody titer are associated with significantly higher risks of overt and subclinical hypothyroidism.