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.

Genetic analysis of 18 families with tuberous sclerosis complex.

Tuberous sclerosis complex (TSC) is mainly caused by variants in TSC1 and TSC2, which encodes hamartin protein and tuberin protein, respectively. Here, we report clinical and molecular characteristics of 18 families with TSC. High-throughput DNA sequencing was employed to detect variants in all the exons and flanking region of TSC1 and TSC2. TA clone and real-time PCR were performed to verify the pathogenicity of candidate variants. A total of 17 mutations were identified, including 13 mutations in TSC2 and 4 mutations in TSC1. Fifty-six percent (10/18) of the families carried de novo mutations, and 8 of these mutations were not reported previously. Most mutations detected were loss-of-function mutations (15/17). One splice-site mutation (TSC2 c.599 + 5G > A) caused abnormal splicing and was confirmed by in vitro analysis. Facial angiofibromas (94%) and epilepsy (89%) were the most prevalent clinical features in our patients. Treatment with anti-seizure medication (ASM) or in combination with rapamycin results in clinical remission in most patients with TSC-associated seizures (14/15). For genotype-phenotype correlation, patients in our cohort with TSC2 mutations had an earlier onset age and patients with TSC1 showed better response to ASM. Our study has expanded the spectrum of TSC1 and TSC2 causing TSC.

Associations between ambient temperature and adult asthma hospitalizations in Beijing, China: a time-stratified case-crossover study.

BACKGROUND: Studies on the associations between ambient temperature and asthma hospitalizations are limited, and the results are controversial. We aimed to assess the short-term effects of ambient temperature on the risk of asthma hospitalizations and quantify the hospitalization burdens of asthma attributable to non-optimal temperature in adults in Beijing, China. METHODS: We collected daily asthma hospitalizations, meteorological factors and air quality data in Beijing from 2012 to 2015. We applied a time-stratified case-crossover design and fitted a distributed lag non-linear model with a conditional quasi-Poisson regression to explore the association between ambient temperature and adult asthma hospitalizations. The effect modifications of these associations by gender and age were assessed by stratified analyses. We also computed the attributable fractions and numbers with 95% empirical confidence intervals (eCI) of asthma hospitalizations due to extreme and moderate temperatures. RESULTS: From 2012 to 2015, we identified a total of 18,500 hospitalizations for asthma among adult residents in Beijing, China. Compared with the optimal temperature (22 °C), the cumulative relative risk (CRR) over lag 0-30 days was 2.32 with a 95% confidence interval (CI) of 1.57-3.42 for extreme cold corresponding to the 2.5th percentile (- 6.5 °C) of temperature distribution and 2.04 (95% CI 1.52-2.74) for extreme heat corresponding to the 97.5th percentile (29 °C) of temperature distribution. 29.1% (95% eCI 17.5-38.0%) of adult asthma hospitalizations was attributable to non-optimum temperatures. Moderate cold temperatures yielded most of the burdens, with an attributable fraction of 20.3% (95% eCI 9.1-28.7%). The temperature-related risks of asthma hospitalizations were more prominent in females and younger people (19-64 years old). CONCLUSIONS: There was a U-shaped association between ambient temperature and the risk of adult asthma hospitalizations in Beijing, China. Females and younger patients were more vulnerable to the effects of non-optimum temperatures. Most of the burden was attributable to moderate cold. Our findings may uncover the potential impact of climate changes on asthma exacerbations.

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.

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.

Ga-68 EDTA aerosols in evaluation of inhaled-particle deposition and clearance of obstructive pulmonary diseases: A pilot prospective study compared with Galligas.

PURPOSE: 68-gallium (Ga-68) ethylenediaminetetraacetic acid (EDTA) aerosols and Galligas were compared in evaluation of inhaled-particle deposition and clearance in volunteers with or without obstructive pulmonary diseases. METHODS: Nonsmoking healthy volunteers, healthy smokers, asthma patients and patients with chronic obstructive pulmonary disease (COPD) were recruited to undergo the dynamic lung ventilation positron emission tomography/computerized tomography (PET/CT) scans within two consecutive days. The inhaled particles were Ga-68-labelled carbon nanoparticles (Galligas, 30-60 nm in size) and Ga-68-labelled EDTA aerosols (1-2 µm in size), respectively. The volunteers' lung function parameters were measured for comparison. RESULTS: Central deposition and inhomogeneity of both tracers were negatively correlated with lung function parameters, including the ratio of forced expiratory volume at 1 second to forced vital capacity (FEV1 /FVC). The central or hilum deposition of Galligas, but not 68-gallium (Ga-68) EDTA, was negatively correlated with the maximal expiratory flow at 25%, 50% and 75% of the forced vital capacity. Compared with Galligas, Ga-68 EDTA aerosols were more concentrated in the central region in all groups except for the healthy nonsmokers. Ventilation inhomogeneity was more evident when using Ga-68 EDTA aerosols, especially in patients with COPD and asthma patients. In the healthy smokers, the central region accumulated more Ga-68 EDTA at 30 minutes after inhalation than immediately after inhalation. Ga-68 EDTA cleared faster in lungs than Galligas. CONCLUSIONS: Both Galligas and Ga-68 EDTA aerosols can be used for PET/CT lung ventilation scan. However, Ga-68 EDTA aerosols showed more advantages in diagnosis and evaluation of obstructive airway diseases by revealing the inhaled-particle deposition and clearance.

The value of transbronchial lung biopsy in the diagnosis of lymphangioleiomyomatosis.

BACKGROUND: Transbronchial lung biopsy (TBLB) in the diagnosis of lymphangioleiomyomatosis (LAM) is not a common approach, although TBLB is often performed in diffuse lung diseases. We aimed to examine the diagnostic value and safety of TBLB in LAM patients based on the data collected in our center. METHODS: We reviewed LAM patients registered in our LAM Clinic from December 8, 2006, to December 31, 2019. All patients with definite or probable diagnosis of LAM who had been examined using TBLB were included. All available pathology slides were reviewed by an experienced LAM pathologist. All complications were reviewed by the medical records and confirmed using telephone interviews. RESULTS: The pathology results of 86 patients (including 74 definite LAM and 12 probable LAM) were available. The positive rate of TBLB in LAM patients was 49/86 (57.0%). The positive rates of SMA, HMB-45, ER, and PR in LAM patients were 97.6%, 93%, 84.6%, and 78.4% respectively. The positive rate of TBLB was 40%, 60% and 60.8% in patients with CT Grade I, Grade II, and Grade III respectively, and the difference was not significant. Patients who had 3-4 or 5-6 biopsied specimens had a higher rate of diagnosis than those with 1-2 biopsied specimens. Four patients (5.6%) reported pneumothorax. No major hemoptysis was reported. CONCLUSIONS: TBLB is a feasible and safe procedure for obtaining a pathological diagnosis of LAM. Taking more than 2 samples during the biopsy procedure increased the rate of diagnosis.

Lymphangioleiomyomatosis.

Lymphangioleiomyomatosis (LAM) is a slow albeit progressive rare neoplastic disease featured with diffuse thin-walled cysts in lungs and angiomyolipomas in kidneys. LAM affects almost exclusively women and has one of the strongest gender predispositions of any extragenital human disease. Two forms of LAM present clinically, sporadic (S-LAM) and tuberous sclerosis complex-associated (TSC-LAM). TSC is an autosomal dominant genetic multisystems neoplastic disease. A high prevalence of LAM can be detected in adult female TSC patients. Tremendous progress has been made in our understanding and management of this rare disease. Both LAM and TSC are TSC2 or TSC1 mutated diseases that result in overactivation of the mechanistic target of rapamycin (mTOR) pathway. Sirolimus, an mTOR inhibitor, has been approved for LAM treatment in the United States and many other countries. Therapies targeting female sex hormones have shown preclinical efficacy in animal and cell culture-based experiments, but have not been properly investigated clinically. In this review, we summarize current recommendations in the diagnosis and treatment of LAM.

Lung function and systemic inflammation associated with short-term air pollution exposure in chronic obstructive pulmonary disease patients in Beijing, China.

BACKGROUND: Exposure to air pollution is associated with chronic obstructive pulmonary disease (COPD). However, findings on the effects of air pollution on lung function and systemic inflammation in Chinese COPD patients are inconsistent and scarce. This study aims to evaluate the effects of ambient air pollution on lung function parameters and serum cytokine levels in a COPD cohort in Beijing, China. METHODS: We enrolled COPD participants on a rolling basis from December 2015 to September 2017 in Beijing, China. Follow-ups were performed every 3 months for each participant. Serum levels of 20 cytokines were detected every 6 months. Hourly ambient pollutant levels over the same periods were obtained from 35 monitoring stations across Beijing. Geocoded residential addresses of the participants were used to estimate daily mean pollution exposures. A linear mixed-effect model was applied to explore the effects of air pollutants on health in the first-year of follow-up. RESULTS: A total of 84 COPD patients were enrolled at baseline. Of those, 75 COPD patients completed the first-year of follow-up. We found adverse cumulative effects of particulate matter less than 2.5 µm in aerodynamic diameter (PM2.5), nitrogen dioxide (NO2), sulfur dioxide (SO2) and carbon monoxide (CO) on the forced vital capacity % predicted (FVC % pred) in patients with COPD. Further analyses illustrated that among COPD patients, air pollution exposure was associated with reduced levels of serum eotaxin, interleukin 4 (IL-4) and IL-13 and was correlated with increased serum IL-2, IL-12, IL-17A, interferon γ (IFNγ), monocyte displacing protein 1 (MCP-1) and soluble CD40 ligand (sCD40L). CONCLUSION: Acute exposures to PM2.5, NO2, SO2 and CO were associated with a reduction in FVC % pred in COPD patients. Furthermore, short-term exposure to air pollutants increased systemic inflammation in COPD patients; this may be attributed to increased Th1 and Th17 cytokines and decreased Th2 cytokines.

Clinical features and optical coherence tomography findings of retinal astrocytic hamartomas in Chinese patients with tuberous sclerosis complex.

PURPOSE: To investigate the clinical features and spectral-domain optical coherence tomography (SD-OCT) findings of retinal astrocytic hamartoma (RAH) in Chinese patients with tuberous sclerosis complex (TSC). METHODS: The medical records of 91 consecutive patients with established TSC diagnosis were retrospectively reviewed. Fundus findings regarding RAH documented by fundus photography and SD-OCT at presentation were collected and analyzed. RESULTS: RAHs were seen in 69 of the 91 patients (75.8%); 50.7% of these patients showed bilateral retinal involvement. Type 1 RAH was found the most common type with a prevalence of 94.2%, while type 2 and type 3 RAH with 7.2% and 18.8% respectively. A significant correlation between age and RAH types was shown by Fisher's exact test (p < 0.001). By SD-OCT, non-calcified RAHs featured in hyperreflective thickening of the retinal nerve fiber layer with some degree of retinal disorganization, while multinodular calcified RAHs characterized with moth-eaten appearances representing intraretinal calcification with posterior dense optical shadowing. CONCLUSION: A higher prevalence of TSC-associated RAH but an unexpected lower prevalence of calcified RAHs was shown in Chinese compared with that of Caucasians. SD-OCT can be used to facilitate the detection and follow-up of RAHs.

Pulmonary benign metastasizing leiomyomas: a case series of 23 patients at a single facility.

BACKGROUND: Pulmonary benign metastasizing leiomyoma (PBML) is a rare disease characterized by leiomyoma of benign histopathology existing in the lungs. Because of its rarity, limited literature with a single case or small number of cases has been regarding to the clinical course, pathology or management of PBML. METHODS: A retrospective study was performed of all PBML cases diagnosed and managed at Peking Union Medical College Hospital (PUMCH) from 2001 to 2019. The clinical characteristics, pathology, treatment and outcomes of each case were studied. RESULTS: There were 25 PBML patients identified in the 19-year period in PUMCH, and 23 patients' data was analyzed. The median age at diagnosis was 46 years. There were 7 patients (30.4%) diagnosed with postmenopausal status. Two patients (8.7%) had no uterine leiomyoma, and 3 patients (13.0%) had no gynecologic surgery history. Immunohistochemistry of most lesions demonstrated positive for desmin, SMA and Estrogen/Progesterone Receptors; and negative for S-100 were shown in 7 cases. After curative or diagnostic surgeries for the PBML, several treatments from observation to medical or surgical castration were performed. Nine premenopausal patients preserved their ovaries at first. At a median follow-up of 8 years, 3 patients finally had oophorectomy. CONCLUSIONS: PBML is a rare disease and should be treated by individualization according to the patients' age, symptoms and extent of lesion. Curative surgery for patients with limited lesions can achieve the complete response. For patients that are young and asymptomatic, close observation is recommended as the first choice. All patients should undergo long-term surveillance.

Too much of a good thing? Global trends in the curtailment of solar PV.

Solar photovoltaic (PV) systems generate electricity with no marginal costs or emissions. As a result, PV output is almost always prioritized over other fuel sources and delivered to the electric grid. However, PV curtailment is increasing as PV composes greater shares of grid capacity. In this paper, we present a novel synthesis of curtailment in four key countries: Chile, China, Germany, and the United States. We find that about 6.5 million MWh of PV output was curtailed in these countries in 2018. We find that: Policy and grid planning practices influence where, when, and how much PV is curtailed; Some PV curtailment is attributable to limited transmission capacity connecting remote solar resources to load centers; PV curtailment peaks in the spring and fall, when PV output is relatively high but electricity demand is relatively low. We discuss available measures to reduce PV curtailment as well as increasing PV curtailment in the contexts of evolving grids and energy technologies.

Global lung function initiative 2012 reference values for spirometry in Asian Americans.

BACKGROUND: Spirometry reference values specifically designed for Asian Americans are currently unavailable. The performance of Global Lung Function Initiative 2012 (GLI-2012) equations on assessing spirometry in Asian Americans has not been evaluated. This study aimed to assess the fitness of relevant GLI-2012 equations for spirometry in Asian Americans. METHODS: Asian subjects who never smoked and had qualified spirometry data were extracted from the National Health and Nutrition Examination Survey (NHANES) 2011-2012. Z-scores of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and FEV1/FVC were separately constructed with GLI-2012 equations for North East (NE) Asians, South East (SE) Asians, and individuals of mixed ethnic origin (Mixed). In addition, Proportions of subjects with observed spirometry data below the lower limit of normal (LLN) were also evaluated on each GLI-2012 equation of interest. RESULTS: This study included 567 subjects (250 men and 317 women) aged 6-79 years. Spirometry z-scores (z-FEV1, z-FVC, and z-FEV1/FVC) based on GLI-2012 Mixed equations had mean values close to zero (- 0.278 to - 0.057) and standard deviations close to one (1.001 to 1.128); additionally, 6.0% (95% confidence interval (CI) 3.1-8.9%) and 6.4% (95% CI 3.7-9.1%) of subjects were with observed data below LLN for FEV1/FVC in men and women, respectively. In contrast, for NE Asian equations, all mean values of z-FEV1 and z-FVC were smaller than - 0.5; for SE Asian equations, mean values of z-FEV1/FVC were significantly smaller than zero in men (- 0.333) and women (- 0.440). CONCLUSIONS: GLI-2012 equations for individuals of mixed ethnic origin adequately fitted spirometry data in this sample of Asian Americans. Future studies with larger sample sizes are needed to confirm these findings.

Secondary pulmonary alveolar proteinosis: a single-center retrospective study (a case series and literature review).

BACKGROUND: Secondary pulmonary alveolar proteinosis (sPAP) is an extremely rare disease. The clinical features of sPAP patients remain to be summarizeds. METHODS: Patients pathologically diagnosed with PAP and with negative results for anti-granulocyte macrophage colony stimulating factor (GM-CSF) autoantibodies from Peking Union Medical College Hospital between January 2000 and July 2016 were retrospectively studied. The PubMed database was also searched for literature to collect published cases. RESULTS: In our center, nine patients were diagnosed as sPAP with a median age of 37 years. Hematological disorders, including myelodysplastic syndrome (MDS), chronic myelogenous leukemia (CML), and pulmonary tuberculosis (TB) infection were the underlying diseases. Cases secondary to MDS had very poor prognosis as all of them survived less than 2 years after their diagnosis, while those secondary to TB had favorable prognosis. Only 33.3% of cases showed interlobular septal thickening in our sPAP group. Through literature review, 164 sPAP cases were collected. The age at diagnosis was 45.0 ± 14.8 years old and the gender radio was 1.20:1 (M:F). 61.9% of cases were diagnosed by bronchoscopy. MDS and CML were common underlying diseases in 34.1% and 15.2% of patients, respectively. Patients with sPAP secondary to hematological diseases had a short survival time and half of them died within 14.95 months after diagnosis. CONCLUSIONS: MDS and TB infection were the most frequent underlying causes of sPAP in this single-center research in China, with cases secondary to MDS having a poor survival rate. sPAP was more likely to be secondary to hematological disorders, especially MDS and CML and had a fairly poor prognosis in published cases. sPAP should be suspected in PAP patients whose CT scan presents only ground-glass opacities without interlobular septal thickening.

A novel homozygous complex deletion in CFTR caused cystic fibrosis in a Chinese patient.

Cystic fibrosis (CF) is the most frequent lethal genetic disorder among Caucasians, but is considered to be a very rare disease in Chinese population. Here, we present an 11-year-old Chinese CF patient with disseminated bronchiectasis and salty sweat, for whom exon sequencing followed by multiplex ligation-dependent probe amplification analysis of the CFTR gene was applied for mutation screening. A homozygous deletion involving exon 20 of CFTR was observed in the patient's genome. Molecular characterization of the breakpoints indicated that both alleles of this locus had an identical novel complex rearrangement (c.3140-454_c.3367+249del931ins13, p.R1048_G1123del), leading to an in-frame removal of 76 amino acid residues in the second transmembrane domains of the CFTR protein. Although a same haplotype containing this complex rearrangement was observed on both of the maternal and paternal alleles, the parents denied any blood relationship as far as they know. Genome-wide homozygosity mapping was performed through SNP microarray and only a single homozygous interval of ~14.1 Mb at chromosome 7 containing the CFTR gene was observed, indicating the possible origin of the deletion from a common ancestor many generations ago. This study expands the mutation spectrum of CFTR in patients of Chinese origin and further emphasizes the necessity of MLPA analysis in mutation screening for CF patients.

Tsc1 deficiency-mediated mTOR hyperactivation in vascular endothelial cells causes angiogenesis defects and embryonic lethality.

This is a study on the role of tuberous sclerosis complex1 (TSC1) mutation and mTOR activation in endothelial cells during angiogenic and embryonic development. Past studies had shown that Tsc1/Tsc2 mutant genes lead to overactivation of mTOR in the regulating pathways in developing fetus. We used conditional Cre-loxp gene knockout approach to delete Tsc1 in mice's endothelial cells in our experimental models. Similarly, activation of mTOR signaling in endothelial cells of these embryos (Tie2-Cre/Tsc1(-/-)) was found. Majority of Tie2-Cre/Tsc1(-/-) embryos died at embryonic day 14.5 in utero. Cardiovascular defects, subcutaneous edema and hemorrhage were present among them. Whole-mount immunostaining in these embryos revealed a disorganized vascular network, defective sprouting of vessels in yolk sac and thickening of the labyrinth layer in the placenta. A thinner ventricular wall with disorganized trabeculae was present in the hearts of Tie2-Cre/Tsc1(-/-) embryos. Endothelial cells in Tsc1-deficient mice showed defective mitochondrial and endoplasmic reticular morphology, but no significant change was observed in cell junctions. The mutant embryos displayed significantly reduced cell proliferation, increased apoptosis and disturbed expression of angiogenic factors. A cohort of mice was treated prenatally with mTOR inhibitor rapamycin. The offspring of these mutant mice survived up to 22 days after birth. It was concluded that physiological TSC1-mTOR signaling in endothelial cells is crucial for vascular development and embryogenesis. We postulated that disruption of normal angiogenic pathways through hyperactive mTOR signaling maybe the mechanism that lead to deranged vascular pathogenesis in the tuberous sclerosis complex.

Diffuse Cystic Lung Diseases: Diagnostic Considerations.

Diffuse cystic lung disease (DCLD) is a group of heterogeneous diseases that present as diffuse cystic changes in the lung on computed tomography of the chest. Most DCLD diseases are rare, although they might resemble common diseases such as emphysema and bronchiectasis. Main causes of DCLD include lymphangioleiomyomatosis, Birt-Hogg-Dubé syndrome, pulmonary Langerhans cell histiocytosis, lymphoid interstitial pneumonia, amyloidosis, light-chain deposition disease, Sjögren syndrome, and primary or metastatic neoplasm. We discuss clinical factors that are helpful in the differential diagnosis of DCLDsuch as sex and age, symptoms and signs, extrapulmonary presentations, cigarette smoking, and family history. Investigations for DCLD include high-resolution computed tomography, biochemical and histopathological studies, genetic tests, pulmonary function tests, and bronchoscopic and video-assisted thoracoscopic biopsies. A proposed diagnostic algorithm would enhance ease of diagnosing most cases of DCLD.

Coexistence of pulmonary lymphangioleiomyomatosis and pulmonary angiomyolipoma.

BACKGROUND: Lymphangioleiomyomatosis (LAM) and angiomyolipoma are two different, but related rare diseases. To the best of our knowledge, pulmonary LAM and pulmonary angiomyolipoma have not previously been observed in the same patient. CASE PRESENTATION: A 38-year-old woman presented with a dry cough and left flank pain. She had a right nephrectomy for renal angiomyolipoma 17 years ago. A magnetic resonance imaging scan demonstrated a round mass in the left kidney. A chest computed tomography scan demonstrated scattered small thin-walled cysts and multifocal round nodules in both lungs. A lung biopsy via video-assisted thoracoscopic surgery revealed that the cysts and nodules were manifestations of LAM and angiomyolipomas, respectively. After sirolimus therapy, the renal angiomyolipoma and metastasized pulmonary angiomyolipomas shrank, but pulmonary cysts were unchanged. CONCLUSIONS: LAM and angiomyolipoma are significantly associated, and may coexist in the lungs in rare cases. Sirolimus is effective for both renal angiomyolipoma and metastasized pulmonary angiomyolipomas.

Occupational inhalational exposure and serum GM-CSF autoantibody in pulmonary alveolar proteinosis.

OBJECTIVES: Although the serum granulocyte-macrophage colony stimulating factor autoantibody (GMAb) levels have been recognised as a diagnostic marker in primary pulmonary alveolar proteinosis (PAP), their role in PAP with occupational inhalational exposure (PAPo) remains unclear. METHODS: Forty-five consecutive patients with PAP were enrolled. Each patient with PAP was assessed for baseline clinical characteristics, chest high-resolution CT (HRCT), serum GMAb and occupational exposure. Fifty healthy controls were included to define normal ranges for GMAb levels. Ninety-seven hospital controls with other respiratory diseases were included to establish prevalence of a history of occupational inhalation exposure. RESULTS: According to the serum GMAb cut-off value of 2.39 µg/mL, 84.4% of the recruited patients with PAP had positive serum GMAb with a median level of 28.7 µg/mL, defined as autoimmune PAP, and the remaining 15.6% had negative serum GMAb with a median level of 0.16 µg/mL, defined as non-autoimmune PAP. Also, 34.2% of patients with autoimmune PAP had a history of occupational inhalational exposure, which was not significantly higher than that of hospital controls (34.2% vs 19.6%, p=0.072). Four patients with PAPo showed negative GMAb. Their arterial oxygen tension, pulmonary function parameters and chest HRCT features were significantly different when compared with patients with autoimmune PAP (p<0.05). These four non-autoimmune occupational lung disease cases culminated in 3 deaths and a lung transplant. CONCLUSIONS: A number of patients with PAP who may have occupational inhalational exposure and negative serum GMAb represent a high possibility of silicoproteinosis and very poor survival.