Intraoperative mechanical ventilation and incidence of pneumothorax in lymphangioleiomyomatosis.

Patients with lymphangioleiomyomatosis (LAM) are considered high risk for most surgeries and require specific anesthetic considerations mainly because of the common spontaneous pneumothorax (PTX). To explore whether intraoperative mechanical ventilation could increase the risk of PTX in those patients, we included 12 surgical patients with LAM in this study, of whom four (33.3%) experienced postoperative PTX. According to our results, patients with higher CT grade, poorer pulmonary function, and a history of preoperative PTX might be more likely to develop postoperative PTX. However, intraoperative mechanical ventilation did not show obvious influence, which might help clinicians reconsider the perioperative management of LAM patients.

Risk factors associated with severe adverse events in patients with relapsing polychondritis undergoing flexible bronchoscopy.

BACKGROUND: Patients with relapsing polychondritis (RP) sometimes experience upper airway collapse or lower airway stenosis, and bronchoscopy may provide a valuable typical image to confirm the diagnosis. This study aimed to identify potential risk factors associated with severe adverse effects during bronchoscopy. METHODS: We performed a retrospective cohort study of 82 consecutive patients with RP hospitalized at Peking Union Medical College Hospital between January 1, 2012 and December 31, 2022. Clinical features and disease patterns were compared among patients with RP undergoing bronchoscopy with or without severe adverse effects. Binary logistic regression analysis was performed to identify the associated risk factors. RESULTS: For patients with RP undergoing bronchoscopy with severe adverse effects, the forced vital capacity (FVC), forced vital capacity percent predicted values (FVC%), and peak expiratory flow were significantly lower (P = 0.001, P = 0.001, and P = 0.021, respectively) than those in the non-severe adverse effect subgroup. Binary logistic regression analysis revealed that low FVC% (odds ratio, 0.930; 95% confidence interval, 0.880-0.982; P = 0.009) was an independent risk factor for severe adverse events in patients undergoing bronchoscopy. CONCLUSIONS: Low FVC or FVC% suggests a high risk of severe adverse effects in patients with RP undergoing bronchoscopy. Patients with such risk factors should be carefully evaluated before bronchoscopy and adequately prepared for emergency tracheal intubation or tracheostomy.

Mutations in CFAP47, a previously reported MMAF causative gene, also contribute to the respiratory defects in patients with PCD.

BACKGROUND: Primary ciliary dyskinesia (PCD) is a genetic ciliopathy characterized by dysfunction of motile cilia. Currently, approximately 50 causative genes accounting for 60%-70% of all PCD cases have been identified in PCD-affected individuals, but the etiology in approximately 30%-40% of PCD cases remains unknown. METHODS: We analyzed the clinical and genetic data of two PCD individuals who were suspected of having PCD. Whole-exome sequencing and Sanger sequencing were performed to identify and verify the variants in CFAP47. We also evaluated the expression of CFAP47 by real-time quantitative PCR and immunofluorescence. Transmission electron microscopy in respiratory epithelial cells was also conducted to analyze ciliary function. RESULTS: Two hemizygous missense variants of X-linked CFAP47 in two unrelated PCD individuals were identified. The expression of CFAP47 in two PCD individuals was significantly reduced in vivo and in vitro assays. A reduction in the amount of epithelial ciliary cells and basal bodies from PCD individuals was also observed. CONCLUSIONS: We describe two hemizygous missense variants of X-linked CFAP47 in two unrelated PCD individuals and prove CFAP47 variants are related to a reduced number of epithelial ciliary cells. Therefore, we suggest that CFAP47 should be known as a novel pathogenic gene of human PCD.

GOLM1 Promotes Pulmonary Fibrosis through Upregulation of NEAT1.

Idiopathic pulmonary fibrosis (IPF) is a lethal progressive disease with elusive molecular mechanisms and limited therapeutic options. Aberrant activation of fibroblasts is a central hallmark of lung fibrosis. Here, we report that Golgi membrane protein 1 (GOLM1, also known as GP73 or GOLPH2) was increased in the lungs of patients with pulmonary fibrosis and mice with bleomycin (BLM)-induced pulmonary fibrosis. Loss of GOLM1 inhibited proliferation, differentiation, and extracellular matrix deposition of fibroblasts, whereas overexpression of GOLM1 exerted the opposite effects. Similarly, worsening pulmonary fibrosis after BLM treatment was observed in GOLM1-knock-in mice, whereas BLM-treated Golm1-knockout mice exhibited alleviated pulmonary fibrosis and collagen deposition. Furthermore, we identified long noncoding RNA NEAT1 downstream of GOLM1 as a potential mediator of pulmonary fibrosis through increased GOLM1 expression. Depletion of NEAT1 inhibited fibroblast proliferation and extracellular matrix production and reversed the profibrotic effects of GOLM1 overexpression. Additionally, we identified KLF4 as a downstream mediator of GOLM1 signaling to NEAT1. Our findings suggest that GOLM1 plays a pivotal role in promoting pulmonary fibrosis through the GOLM1-KLF4-NEAT1 signaling axis. Targeting GOLM1 and its downstream pathways may represent a novel therapeutic strategy for treating pulmonary fibrosis.

Effects of COVID-19 infection in patients with autoimmune pulmonary alveolar proteinosis: a single-center study.

BACKGROUND: Autoimmune pulmonary alveolar proteinosis (aPAP) is a rare interstitial lung disease. COVID-19 is associated with worse prognosis in previous lung diseases patients. But the prognosis of aPAP patients after infection with COVID-19 is unclear. In December 2022, China experienced a large-scale outbreak of Omicron variant of the SARS-CoV-2. In this study, we aim to explore the clinical outcomes of aPAP patients infected with COVID-19. RESULTS: A total of 39 aPAP patients were included in this study. 30.77% patients had a decrease in oxygen saturation after COVID-19 infection. We compared the two groups of patients with or without decreased oxygen saturation after COVID-19 infection and found that patients who had previous oxygen therapy (decreased oxygen saturation vs. non decreased oxygen saturation: 6/12 vs. 4/27, P = 0.043), with lower baseline arterial oxygen partial pressure (74.50 ± 13.61 mmHg vs. 86.49 ± 11.92 mmHg, P = 0.009), lower baseline DLCO/VA% [77.0 (74.3, 93.6) % vs. 89.5 (78.2, 97.4) %, P = 0.036], shorter baseline 6MWD [464 (406, 538) m vs. 532 (470, 575) m, P = 0.028], higher disease severity score (P = 0.017), were more likely to have decreased oxygen saturation after COVID-19 infection. CONCLUSION: aPAP patients with poor baseline respiration have a higher probability of hypoxia after COVID-19 infection, but fatal events were rare.

Lack of CFAP54 causes primary ciliary dyskinesia in a mouse model and human patients.

Primary ciliary dyskinesia (PCD) is a highly heterogeneous recessive inherited disorder. FAP54, the homolog of CFAP54 in Chlamydomonas reinhardtii, was previously demonstrated as the C1d projection of the central microtubule apparatus of flagella. A Cfap54 knockout mouse model was then reported to have PCD-relevant phenotypes. Through whole-exome sequencing, compound heterozygous variants c.2649_2657delinC (p. E883Dfs*47) and c.7312_7313insCGCAGGCTGAATTCTTGG (p. T2438delinsTQAEFLA) in a new suspected PCD-relevant gene, CFAP54, were identified in an individual with PCD. Two missense variants, c.4112A>C (p. E1371A) and c.6559C>T (p. P2187S), in CFAP54 were detected in another unrelated patient. In this study, a minigene assay was conducted on the frameshift mutation showing a reduction in mRNA expression. In addition, a CFAP54 in-frame variant knock-in mouse model was established, which recapitulated the typical symptoms of PCD, including hydrocephalus, infertility, and mucus accumulation in nasal sinuses. Correspondingly, two missense variants were deleterious, with a dramatic reduction in mRNA abundance from bronchial tissue and sperm. The identification of PCD-causing variants of CFAP54 in two unrelated patients with PCD for the first time provides strong supportive evidence that CFAP54 is a new PCD-causing gene. This study further helps expand the disease-associated gene spectrum and improve genetic testing for PCD diagnosis in the future.

Association between the temperature difference and acute exacerbations of chronic obstructive pulmonary disease: A time-series analysis with 143,318 hospital admissions in Beijing, China.

Purpose: Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) has the adverse influence on quality of life and creates significant healthcare costs. However, there were sparse studies investigating the correlation between AECOPD hospital admissions and temperature change. Therefore, it is noteworthy to investigate the impact of various temperature differences and recognize the susceptible population. The purpose of this study was to investigate the impact of temperature differences on AECOPD hospital admissions, and to give potentially helpful material for disease preventative efforts. Methods: The distributed lag non-linear model was adopted to characterize the exposure-response relationship and to assess the impact of temperature difference. The stratified analysis and sensitivity analysis were also conducted to determine the susceptible populations and examine the robustness of the results. Results: There were 143,318 AECOPD hospital admissions overall during the study period. The AECOPD hospital admissions had significant association with the daily mean temperature difference (DTDmean) such as the extreme-cold temperature difference (1st DTDmean), the ultra-cold temperature difference (5th DTDmean), the ultra-hot temperature difference (95th DTDmean) and the extreme-hot temperature difference (99th DTDmean). Besides, there was the "U-shaped" association between DTDmean and 21 days cumulative relative risk of AECOPD. Conclusion: The AECOPD hospital admissions was correlated with the DTDmean temperature differences, especially the extreme-cold and extreme-hot temperature difference. Moreover, people older than 65 years were more susceptible to the extreme-hot and extreme-cold temperature difference.

Updated severity and prognosis score of pulmonary alveolar proteinosis: A multi-center cohort study in China.

Background: The high-resolution computed tomography (HRCT) score is an important component of the severity and prognosis score of pulmonary alveolar proteinosis (SPSP). However, the HRCT score in SPSP only considers the extent of opacity, which is insufficient. Methods: We retrospectively evaluated HRCT scores for 231 patients with autoimmune pulmonary alveolar proteinosis (APAP) from three centers of the China Alliance for Rare Diseases. The SPSPII was created based on the overall density and extent, incorporating the SPSP. The severity of APAP patients was assessed using disease severity scores (DSS), SPSP, and SPSPII to determine the strengths and weaknesses of the different assessment methods. We then prospectively applied the SPSPII to patients before treatment, and the curative effect was assessed after 3 months. Results: The HRCT overall density and extent scores in our retrospective analysis were higher than the extent scores in all patients and every original extent score severity group, as well as higher related to arterial partial oxygen pressure (PaO2) than extent scores. The mild patients accounted for 61.9% based on DSS 1-2, 20.3% based on SPSP 1-3, and 20.8% based on SPSPII 1-3. Based on SPSP or SPSPII, the number of severe patients deteriorating was higher in the mild and moderate groups. When applied prospectively, arterial PaO2 differed between any two SPSPII severity groups. The alveolar-arterial gradient in PaO2 (P[A-a]O2), % predicted carbon monoxide diffusing capacity of the lung (DLCO), and HRCT score were higher in the severe group than in the mild and moderate groups. After diagnosis, mild patients received symptomatic treatment, moderate patients received pure whole lung lavage (WLL) or granulocyte-macrophage colony-stimulating factor (GM-CSF) therapy, and severe patients received WLL and GM-CSF therapy. Importantly, the SPSPII in mild and severe groups were lower than baseline after 3 months. Conclusion: The HRCT density and extent scores of patients with APAP were better than the extent score. The SPSPII score system based on smoking status, symptoms, PaO2, predicted DLCO, and overall HRCT score was better than DSS and SPSP for assessing the severity and efficacy and predicting the prognosis. Trial registration: ClinicalTrial.gov, identifier: NCT04516577.

Determinants of Progression and Mortality in Lymphangioleiomyomatosis.

BACKGROUND: Lymphangioleiomyomatosis is a progressive diffuse cystic lung disease with approximately 85% survival at 10 years. The determinants of disease progression and mortality after the introduction of sirolimus therapy and vascular endothelial growth factor D (VEGF-D) as a biomarker have not been well defined. RESEARCH QUESTION: Which factors, including VEGF-D and sirolimus therapy, influence disease progression and survival prognosis in patients with lymphangioleiomyomatosis? STUDY DESIGN AND METHODS: The progression dataset and the survival dataset included 282 and 574 patients, respectively, from Peking Union Medical College Hospital, Beijing, China. A mixed-effects model was used to compute the rate of decline in FEV1, and generalized linear models were used to identify variables affecting FEV1 decline. A Cox proportional hazards model was used to explore the association between clinical variables and the outcomes of death or lung transplantation in patients with lymphangioleiomyomatosis. RESULTS: VEGF-D levels and sirolimus treatment were associated with FEV1 changes and survival prognosis. Compared with patients with VEGF-D of < 800 pg/mL at baseline, patients with VEGF-D of ≥ 800 pg/mL lost FEV1 faster (SE, -38.86 mL/y; 95% CI, -73.90 to -3.82 mL/y; P = .031). The 8-year cumulative survival rates of patients with VEGF-D of ≥ 2,000 pg/mL and < 2,000 pg/mL were 82.9% and 95.1%, respectively (P = .014). The generalized linear regression model also demonstrated the benefit of delaying the decline of FEV1 by 65.56 mL/y (95% CI, 29.06-102.06 mL/y) in patients treated with sirolimus compared with those without sirolimus (P < .001). The 8-year risk of death was reduced by 85.1% (hazard ratio, 0.149; 95% CI, 0.075-0.299) after sirolimus treatment. After inverse treatment probability weighting, the risks of death in the sirolimus group were reduced by 85.6%. CT scan results of grade III severity were associated with worse progression than results of grades I or II severity. Patients with baseline FEV1 of 70% predicted or St. George's Respiratory Questionnaire Symptoms domain 50 or higher predicted a higher risk of worse survival. INTERPRETATION: Serum VEGF-D levels, a biomarker of lymphangioleiomyomatosis, are associated with disease progression and survival. Sirolimus therapy is associated with slower disease progression and better survival in patients with lymphangioleiomyomatosis. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT03193892; URL: www. CLINICALTRIALS: gov.

Association between Norovirus epidemics and school toilets design and management in Chengdu City / 中国学校卫生

Objective@#To analyze the relationship between the toilet design and sanitary condition of primary and secondary schools in Chengdu and the epidemic situation of Norovirus infection, so as to provide scientific references for school toilet design and Norovirus prevention and control.@*Methods@#A total of 78 cases of norovirus epidemics from 2019 to 2020 were included in this study. These epidemics happened in 78 schools and the causes were indicated as human-to-human transmission. The Chi square and Mann-Whitney U test were used to compare categorical and continuous data respectively. Unconditional binary Logistic regression was used to examine the multivariate associations.@*Results@#Most epidemics happened from October in 2019 to March in 2020(79.49%, 62 cases), in primary schools (71.79%, 56 cases) and in the center area (52.56%, 41 cases). The median of the case number in each epidemic was 10. Overall, 56 schools (71.79%) were equipped with toilets which were flushed independently, and 22 schools (28.21%) were equipped with toilets which were flushed uniformly. There were 27 schools (34.62%) that did not have enough water taps. Logistic regression analysis found that those with toilets flushed uniformly had a stronger epidemic, compared to the schools with toilets flushed independently( OR=5.53, 95%CI=1.63-18.76, P <0.05).@*Conclusion@#In order to prevent intestinal infectious diseases , it is suggested that schools should design or reconstruct independent flushing toilets with adequate faucets.

Long-term efficacy and safety of sirolimus for retinal astrocytic hamartoma associated with tuberous sclerosis complex.

Mammalian target of rapamycin (mTOR) inhibitors (sirolimus or everolimus) have been demonstrated effective in reducing the size of tuberous sclerosis complex (TSC)-associated retinal astrocytic hamartoma (RAH) in short term. To investigate the long-term efficacy and safety of sirolimus on TSC-associated RAH, 13 TSC-associated RAH patients (59 RAH lesions) who received sirolimus therapy for at least 2 years were retrospectively enrolled in this study. Changes in the maximal thickness (MT) of RAH on optical coherence tomography and the longest base diameter (LBD) of RAH on color fundus photography were assessed. The results showed that for a mean follow-up of 39 months, sirolimus was associated with a mean reduction of 14.6% in MT and 6.8% in LBD of RAHs. The main impacts of sirolimus occurred within the first 6-12 months, with 14.8% reduction in MT and 4.7% reduction in LBD. Mouth ulceration (10 [76.9%]) and acne (9 [69.2%]) were the most common adverse events. These follow-up data support the long-term use of sirolimus in TSC-associated RAH patients, and persistent use of sirolimus possibly prevents tumor regrowth.

Gene mutations in sporadic lymphangioleiomyomatosis and genotype-phenotype correlation analysis.

BACKGROUND: Sporadic lymphangioleiomyomatosis (S-LAM) is a rare neoplasm with heterogeneous clinical features that is conventionally considered to be related to TSC2. This study serves to elucidate the mutation landscape and potential correlation between S-LAM genomic profiles and clinical phenotypes. METHODS: Genomic profiles of 22 S-LAM patients were obtained by sequencing genomic DNA and cell-free DNA from various specimens using an NGS (next-generation sequencing)-based tumor-driver gene panel. Detected mutations were summarized. Symptoms, serum vascular endothelial growth factor D (VEGF-D) values, pulmonary function, and six-minute walk distance (6MWD) were compared among groups with different TSC2 status and genotypes to analyze genotype-phenotype correlations. RESULTS: 67 Variants in 43 genes were detected, with a TSC2 mutation detection rate of 68.2%. The TSC2 detection rate was similar in specimens obtained either through transbronchial lung biopsy (TBLB) or surgical lung biopsy (70.0% vs. 69.2%, p > 0.05). A novel mutation in VEZF1 (c.A659G) was detected in four participants and may represent a mild disease state. TSC2 mutation was significantly related to a shorter 6MWD (p < 0.05), and a higher percentage of VEGF-D over 800 pg/mL (p < 0.05); stop-gain mutation was significantly related to a higher prevalence of pneumothorax. CONCLUSIONS: Tumor-driver mutations in genes other than TSC2 may have a role in S-LAM, and TBLB specimens are practical alternatives for genomic analysis. TSC2 mutation detectability and types are related to the disease severity and phenotypes of S-LAM.

Increased Risk of Hospital Admission for Asthma from Short-Term Exposure to Low Air Pressure.

Purpose: Asthma has a major impact on patients' quality of life, mortality, and healthcare burden. Some evidence suggests that environmental factors may trigger asthma. However, there has been limited research on the relationship between air pressure and asthma hospital admissions, especially in China. Thus, we aimed to study the influence of air pressure and identify potentially susceptible populations. Methods: The study data were gathered from hospitalization records with a primary diagnosis of asthma from all secondary and tertiary hospitals in Beijing from January 1, 2013, to December 31, 2016. The study examined the association between the risk of asthma and air pressure using a distributed lag non-linear model (DLNM). We also performed a stratified analysis to identify the susceptible populations. Results: A total of 23,697 asthma hospital admissions were included in the study. We found that the relative risk (RR) and the 7-day cumulative relative risk (CRR) of asthma had an approximate negative correlation with air pressure. At the same time, we found that the association was most apparent on the day of exposure (lag = 0). Conclusion: Ambient air pressure had an approximately negative correlation with daily asthma hospital admissions in Beijing, China. That means the risk of hospital admission for asthma would be increased by low air pressure. Furthermore, air pressure has a significant effect on asthma only on the day of exposure. It is possibly significant to protect the vulnerable on days with low air pressure, especially those younger than 65 years.

Sirolimus reduces the risk of pneumothorax recurrence in patients with lymphangioleiomyomatosis: a historical prospective self-controlled study.

BACKGROUND: Spontaneous pneumothorax has a high incidence and high rate of recurrence in patients with lymphangioleiomyomatosis (LAM). The risk factors for pneumothorax and the effects of sirolimus on pneumothorax in patients with LAM are unknown. In our study, multivariate logistic regression was applied to a cross-sectional cohort to investigate factors associated with pneumothorax in LAM patients. Kaplan-Meier analysis was applied in the historical prospective self-controlled study to determine whether sirolimus reduces the risk of pneumothorax recurrence in patients with LAM. RESULTS: Of the 399 patients registered with LAM-CHINA at our center between May 10, 2017 and August 31, 2020, 142 had a history of pneumothorax at registration. High CT grade and age at presentation ≤ 35 years were associated with a higher risk of pneumothorax in patients with LAM. Postmenopausal status was correlated with a lower risk of pneumothorax. In the historical prospective self-controlled study, the 5-year probability of pneumothorax recurrence was 80% lower in the sirolimus group than in the control group (hazard ratio for pneumothorax recurrence, 0.20; 95% CI, 0.14 to 0.30, P < 0.001 by log-rank test). CONCLUSION: Sirolimus reduced the risk of pneumothorax recurrence in LAM patients.

Clinical and Genetic Comparison of Birt-Hogg-Dubé Syndrome (Hornstein-Knickenberg Syndrome) in Chinese: A Systemic Review of Reported Cases.

Background: Birt-Hogg-Dubé syndrome (BHD), also named Hornstein-Knickenberg syndrome, is a rare autosomal dominant disease characterized by lung cysts, recurrent pneumothoraxes, renal cell carcinoma and skin fibrofolliculomas. Purpose: This study summarizes the clinical and genetic information of Chinese BHD patients from all available reported cases and explores the relationship between the clinical and genetic spectrum in the hope of improving the prognosis of Chinese BHD patients. Methods: Relative studies were collected by searching PubMed, Cochrane Library, Embase, OVID medicine, SinoMed, Web of Science, China National Knowledge Infrastructure, Wanfang Data and China Hospital Knowledge Database from January 1, 1977 to December 31, 2021. The search strategy included the following term keys: (Birt-Hogg-Dubé syndrome OR Hornstein-Kinckenberg syndrome OR familial pulmonary cysts OR familial spontaneous pneumothorax OR fibrofolliculomas OR trichodiscomas OR inherited renal cancer syndromes OR FLCN) AND (Chinese OR China). Results: In total, 287 Chinese patients from 143 families described in 31 references were included in this article. Chinese BHD patients tended to present more pulmonary symptoms but fewer skin lesions and renal malignancies, which appeared to be atypical when compared with Caucasian patients. The FLCN mutation spectrum among Chinese BHD patients was established with the mutational hot spot c.1285depC/delC as the most frequent mutation. In addition, this mutation spectrum also showed some differences from other races, with a relatively frequent large deletion c.872-429_1740+1763del (exon 9-14 deletion) reported only in Chinese individuals but no observation of the two mutational hot spots found in Japanese individuals. We also attempted to establish potential pheno-genotype correlations in Chinese BHD patients, but the results were negative. Conclusion: To improve the prognosis of BHD patients, physicians need to increase their awareness of BHD by focusing on the family history of pneumothorax as well as skin lesions in patients with lung cysts and promptly advising patients on genetic sequencing.

Transcriptional regulation and small compound targeting of ACE2 in lung epithelial cells.

Angiotensin-converting enzyme 2 (ACE2) is the receptor of COVID-19 pathogen SARS-CoV-2, but the transcription factors (TFs) that regulate the expression of the gene encoding ACE2 (ACE2) have not been systematically dissected. In this study we evaluated TFs that control ACE2 expression, and screened for small molecule compounds that could modulate ACE2 expression to block SARS-CoV-2 from entry into lung epithelial cells. By searching the online datasets we found that 24 TFs might be ACE2 regulators with signal transducer and activator of transcription 3 (Stat3) as the most significant one. In human normal lung tissues, the expression of ACE2 was positively correlated with phosphorylated Stat3 (p-Stat3). We demonstrated that Stat3 bound ACE2 promoter, and controlled its expression in 16HBE cells stimulated with interleukin 6 (IL-6). To screen for medicinal compounds that could modulate ACE2 expression, we conducted luciferase assay using HLF cells transfected with ACE2 promoter-luciferase constructs. Among the 64 compounds tested, 6-O-angeloylplenolin (6-OAP), a sesquiterpene lactone in Chinese medicinal herb Centipeda minima (CM), represented the most potent ACE2 repressor. 6-OAP (2.5 µM) inhibited the interaction between Stat3 protein and ACE2 promoter, thus suppressed ACE2 transcription. 6-OAP (1.25-5 µM) and its parental medicinal herb CM (0.125%-0.5%) dose-dependently downregulated ACE2 in 16HBE and Beas-2B cells; similar results were observed in the lung tissues of mice following administration of 6-OAP or CM for one month. In addition, 6-OAP/CM dose-dependently reduced IL-6 production and downregulated chemokines including CXCL13 and CX3CL1 in 16HBE cells. Moreover, we found that 6-OAP/CM inhibited the entry of SARS-CoV-2 S protein pseudovirus into target cells. These results suggest that 6-OAP/CM are ACE2 inhibitors that may potentially protect lung epithelial cells from SARS-CoV-2 infection.

Lung function and air pollution exposure in adults with asthma in Beijing: a 2-year longitudinal panel study.

The effect of air pollution on the lung function of adults with asthma remains unclear to date. This study followed 112 patients with asthma at 3-month intervals for 2 years. The pollutant exposure of the participants was estimated using the inverse distance weight method. The participants were divided into three groups according to their lung function level at every visit. A linear mixed-effect model was applied to predict the change in lung function with each unit change in pollution concentration. Exposure to carbon monoxide (CO) and particles less than 2.5 micrometers in diameter (PM2.5) was negatively associated with large airway function in participants. In the severe group, exposure to chronic sulfur dioxide (SO2) was negatively associated with post-bronchodilator forced expiratory flow at 50%, between 25% and 75% of vital capacity % predicted (change of 95% CI per unit: -0.34 (-0.55, -0.12), -0.24 (-0.44, -0.03), respectively). In the mild group, the effect of SO2 on the small airways was similar to that in the severe group, and it was negatively associated with large airway function. Exposure to CO and PM2.5 was negatively associated with the large airway function of adults with asthma. The negative effects of SO2 were more evident and widely observed in adults with severe and mild asthma than in adults with moderate asthma. Patients with asthma react differently to air pollutants as evidenced by their lung function levels.

Novel mutation c.1210-3C > G in cis with a poly-T tract of 5T affects CFTR mRNA splicing in a Chinese patient with cystic fibrosis.

Cystic fibrosis (CF) is a rare autosomal recessive disease with only one pathogenic gene cystic fibrosis transmembrane conductance regulator (CFTR). To identify the potential pathogenic mutations in a Chinese patient with CF, we conducted Sanger sequencing on the genomic DNA of the patient and his parents and detected all 27 coding exons of CFTR and their flanking intronic regions. The patient is a compound heterozygote of c.2909G > A, p.Gly970Asp in exon 18 and c.1210-3C > G in cis with a poly-T of 5T (T5) sequence, 3 bp upstream in intron 9. The splicing effect of c.1210-3C > G was verified via minigene assay in vitro, indicating that wild-type plasmid containing c.1210-3C together with T7 sequence produced a normal transcript and partial exon 10-skipping-transcript, whereas mutant plasmid containing c.1210-3G in cis with T5 sequence caused almost all mRNA to skip exon 10. Overall, c.1210-3C > G, the newly identified pathogenic mutation in our patient, in combination with T5 sequence in cis, affects the CFTR gene splicing and produces nearly no normal transcript in vitro. Moreover, this patient carries a p.Gly970Asp mutation, thus confirming the high-frequency of this mutation in Chinese patients with CF.

Dynamic Observation of Autophagy and Transcriptome Profiles in a Mouse Model of Bleomycin-Induced Pulmonary Fibrosis.

Pulmonary fibrosis is a group of progressive, fibrotic, and fatal lung diseases, and the role of autophagy in pulmonary fibrosis is controversial. In the current research, we dynamically observed a bleomycin-induced pulmonary fibrosis mouse model after 3, 7, 14, 21, and 28 days and investigated the expression of autophagy markers. We found that autophagy markers were not significantly changed on the indicated days in the mouse lung tissue. Then, RNA-Seq was used to analyze the gene expression and associated functions and pathways in fibrotic lung tissue on different days post-bleomycin. In addition, short time series expression miner (STEM) analysis was performed to explore the temporal post-bleomycin gene expression. Through STEM, continually up- or downregulated profiles did not demonstrate the critical role of autophagy in the development of fibrosis. Furthermore, gene ontology (GO) annotations showed that continually upregulated profiles were mainly related to fibrosis synthesis, extracellular space, and inflammation, while enriched pathways were mainly related to the PI3K-Akt signaling pathway, ECM-receptor interactions, and focal adhesion signaling pathway. For continually downregulated profiles, GO annotations mainly involved sarcomere organization, muscle contraction, and muscle fiber development. The enriched KEGG signaling pathways were the cAMP signaling pathway, cGMP-PKG signaling pathway, calcium signaling pathway, and cardiac muscle contraction. Moreover, we analyzed autophagy-related genes' expression in specific cells from a publicly available database of three human and one animal study of pulmonary fibrosis using single-cell sequencing technology. All results consistently demonstrated no critical role of autophagy in the pathogenesis of pulmonary fibrosis. In summary, autophagy may not critically and consistently change during the development of pulmonary fibrosis at different stages post-bleomycin in a mouse model. These continually up- or downregulated profiles, including gene profiles, and the corresponding functions and pathways may provide mechanistic insights into IPF therapy.