Evaluation of polyhexamethylene guanidine-induced lung injuries by chest CT, pathologic examination, and RNA sequencing in a rat model

AbstractOur aim was to correlate chest CT and pathologic findings of polyhexamethylene guanidine phosphate (PHMG)-induced lung injuries in a rat model, to determine whether PHMG exposure causes lung tumors, and to explore genetic alterations according to PHMG exposure under the guidance of CT. A PHMG solution was intratracheally administrated to 40 male rats. Chest CT was carried out in all rats and both lungs were collected for histopathologic evaluation. At 4- and 8-weeks post-instillation, one lobe of the right lung from 3 rats was subjected to RNA sequencing. At least one abnormal CT finding was found in all rats at all weeks. The major CT findings were inflammation, fibrosis, and tumors in the pathologic analysis, where significant changes were observed over time. The lung lesions remained persistent after 8 weeks of PHMG exposure. In the pathologic analysis, the extent/severity of inflammation did not show statistically significant changes over time, whereas the extent/severity of fibrosis increased continuously up to 6 weeks after PHMG exposure and then decreased significantly at 8 weeks. Bronchiolar-alveolar adenomas which have malignant potential were found in 50% of rats at 6 and 8 weeks after PHMG exposure. Also, several genes associated with lung cancer, acute lung injury, and pulmonary fibrosis were detected. Our study revealed that PHMG-induced lung injury and its changes according to the number of weeks after exposure were demonstrated using chest CT and pathologic evaluation. In addition, we showed that PHMG exposure caused lung tumors and genetic alterations according to PHMG exposure under the guidance of CT.

Download Full-text

Polyhexamethylene Guanidine-induced Lung Injuries and Tumorigenesis in a Rat Model: Radiologic Evaluation With Pathologic Correlation and RNA Sequencing

10.21203/rs.3.rs-33203/v1 ◽

2020 ◽

Author(s):

Cherry Kim ◽

Sang Hoon Jeong ◽

Jaeyoung Kim ◽

Ki Yeol Lee ◽

Jaehyung Cha ◽

...

Keyword(s):

Lung Injury ◽

Rna Sequencing ◽

Rat Model ◽

Genetic Alterations ◽

Lung Tumors ◽

Chest Ct ◽

Pathologic Correlation ◽

Polyhexamethylene Guanidine ◽

Lung Injuries ◽

Pathologic Analysis

Abstract Background: Polyhexamethylene guanidine phosphate (PHMG) is was used as humidifier disinfectants. We aimed to evaluate PHMG-induced lung injuries and their chronological changesin a rat model using chest CT with pathologic correlation, to determine whether PHMG exposure causes lung tumors, and to explore genetic alterations according to PHMG exposure under the guidance of CT.Methods: A PHMG solution was intratracheally administrated to 40 male rats. Chest CT was carried out in all rats and both lungs were collected for histopathologic evaluation. At 4 weeks after instillation, one lobe of the right lung from 3 rats was subjected to RNA sequencing.Results: At least one abnormal CT finding was found in all rats at all weeks. The major CT findings were inflammation, fibrosis, and tumors in the pathologic analysis, where significant changes were observed over time.The lung lesions remained persistent after 8 weeks of PHMG exposure. In the pathologic analysis, the extent/severity of inflammation did not show statistically significant changes over time, whereas the extent/severity of fibrosis increased continuously up to 6 weeks after PHMG exposure and then decreased significantly at 8 weeks. Bronchiolar-alveolar adenomas which have malignant potential were found in 50% of rats at 6 and 8 weeks after PHMG exposure. Also, several genes associated with lung cancer, acute lung injury, and pulmonary fibrosis were detected.Conclusions: PHMG-induced lung injury and its changes according to the number of weeks after exposure were demonstrated using chest CT and pathologic evaluation. In addition, we showed that PHMG exposure caused lung tumors and genetic alterations according toPHMG exposure under the guidance of CT.

Download Full-text

Evaluation of the effect of filtered ultrafine particulate matter on bleomycin-induced lung fibrosis in a rat model using computed tomography, histopathologic analysis, and RNA sequencing

Scientific Reports ◽

10.1038/s41598-021-02140-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Cherry Kim ◽

Sang Hoon Jeong ◽

Jaeyoung Kim ◽

Ja Young Kang ◽

Yoon Jeong Nam ◽

...

Keyword(s):

Particulate Matter ◽

Rna Sequencing ◽

Rat Model ◽

Lung Fibrosis ◽

Chest Ct ◽

Male Rats ◽

Saline Control ◽

Control Group ◽

Histopathologic Evaluation ◽

Pathologic Analysis

AbstractWe aimed to investigate the effect of chronic particulate matter (PM) exposure on bleomycin-induced lung fibrosis in a rat model using chest CT, histopathologic evaluation, and RNA-sequencing. A bleomycin solution was intratracheally administrated to 20 male rats. For chronic PM exposure, after four weeks of bleomycin treatment to induce lung fibrosis, PM suspension (experimental group) or normal saline (control group) was intratracheally administrated for 10 weeks. Chest CT was carried out in all rats, and then both lungs were extracted for histopathologic evaluation. One lobe from three rats in each group underwent RNA sequencing, and one lobe from five rats in each group was evaluated by western blotting. Inflammation and fibrosis scores in both chest CT and pathologic analysis were significantly more aggravated in rats with chronic PM exposure than in the control group. Several genes associated with inflammation and immunity were also upregulated with chronic PM exposure. Our study revealed that chronic PM exposure in a bleomycin-induced lung fibrosis rat model aggravated pulmonary fibrosis and inflammation, proven by chest CT, pathologic analysis, and RNA sequencing.

Download Full-text

Evaluation of the long-term effect of polyhexamethylene guanidine phosphate in a rat lung model using conventional chest computed tomography with histopathologic analysis

PLoS ONE ◽

10.1371/journal.pone.0256756 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0256756

Author(s):

Cherry Kim ◽

Sang Hoon Jeong ◽

Jaeyoung Kim ◽

Ja Young Kang ◽

Yoon Jeong Nam ◽

...

Keyword(s):

Computed Tomography ◽

Rat Model ◽

Chest Ct ◽

P Value ◽

Chest Computed Tomography ◽

Polyhexamethylene Guanidine ◽

Histopathologic Analysis ◽

Guanidine Phosphate ◽

Over Time

There have been no studies on the effects of polyhexamethylene guanidine phosphate (PHMG) after a long period of exposure in the rodent model. We aimed to evaluate long-term lung damage after PHMG exposure using conventional chest computed tomography (CT) and histopathologic analysis in a rat model. A PHMG solution was intratracheally administrated to 24 male rats. At 8, 26, and 52 weeks after PHMG instillation, conventional chest CT was performed in all rats and both lungs were extracted for histopathologic evaluation. At 52 weeks after PHMG instillation, four carcinomas had developed in three of the eight rats (37.5%). Bronchiolo-alveolar hyperplasia and adenoma were found in rats at 8, 26, and 52 weeks post-instillation. The number of bronchiolo-alveolar hyperplasia significantly increased over time (P-value for trend< 0.001). The severity of lung fibrosis and fibrosis scores significantly increased over time (P-values for trend = 0.002 and 0.023, respectively). Conventional chest CT analysis showed that bronchiectasis and linear density scores suggestive of fibrosis significantly increased over time (P-value for trend < 0.001). Our study revealed that one instillation of PHMG in a rat model resulted in lung carcinomas and progressive and irreversible fibrosis one year later based on conventional chest CT and histopathologic analysis. PHMG may be a lung carcinogen in the rat model.

Download Full-text

High dimensional mapping of temporal evolution within the marrow microenvironment in response to FLT3 inhibitor therapy.

Journal of Clinical Oncology ◽

10.1200/jco.2021.39.15_suppl.7020 ◽

2021 ◽

Vol 39 (15_suppl) ◽

pp. 7020-7020

Author(s):

Matthew Newman ◽

Sunil K. Joshi ◽

Daniel Bottomly ◽

Shannon McWeeney ◽

Brian J. Druker ◽

...

Keyword(s):

Rna Sequencing ◽

Targeted Therapies ◽

Temporal Evolution ◽

Genetic Alterations ◽

High Dimensional ◽

Mass Cytometry ◽

Development Of Resistance ◽

Flt3 Inhibitor ◽

Marrow Stroma ◽

Over Time

7020 Background: The advent of genomic sequencing technologies has revealed underlying genetic alterations, such as FLT3 mutations, that can be targeted in acute myeloid leukemia (AML). However, development of resistance limits the durability of response. Recent data has implicated that factors from the bone marrow microenvironment mediate initial resistance to FLT3 inhibitors (FLT3i) in AML. We combined high dimensional characterization techniques, time-of-flight mass cytometry (CyTOF) and RNA sequencing, to examine sequential marrow stromal samples from a subset of patients with FLT3 mutated AML treated with the FLT3i gilteritinib. Here, we report on the heterogeneity and evolution of cell surface and secreted factors over time. Methods: RNA sequencing of primary FLT3-ITD stromal samples (N = 29) from pre-study and on-treatment patients enabled prioritization of candidate targets for CyTOF. Target-specific purified antibodies were purchased pre-conjugated to metal lanthanides or conjugated in house according to manufacturer protocols (after validation via traditional flow cytometry). Primary stromal cells were cultured ex vivo until confluent and were harvested and stained according to a standardized protocol, and subsequently run on a Helios (Fluidigm) mass cytometer. A computational approach was employed to compensate and visualize data via the CATALYST R package. A total of four pre-treatment and four post-gilteritinib timepoint isolates (N = 8) were analyzed. Results: A 36-target mass cytometry panel revealed protein level differences in patients before and after gilteritinib therapy. Dimensional reduction techniques such as MDS and UMAP showed that samples taken from later timepoints clustered together compared to their earlier counterparts with respect to global protein expression. Inflammatory mediators such as IL1-beta and MCP-1 were upregulated in patient stroma soon after gilteritinib treatment and therefore potentially contribute to early resistance. Novel markers previously implicated in early resistance to targeted therapies in AML such as FGF2 and FGFR1 similarly peaked earlier in treatment, mimicking the clinical course of expression observed in marrow stroma of patients treated with another FLT3 inhibitor quizartinib (Traer et al. Cancer Res. 2016). Conclusions: Our findings show that primary marrow stroma evolves during gilteritinib treatment, and that stromal proteins previously reported to promote early resistance to FLT3i are also upregulated during gilteritinib resistance. The heterogeneity of stromal cell isolates detected by mass cytometry highlights the utility of high dimensional tracking of disease course in patients, and may enable a better understanding of how the temporal evolution of the marrow microenvironment contributes to development of resistance to targeted therapies such as gilteritinib and other FLT3i over time.

Download Full-text

Tractotomy using the Penrose drain guide for deep lung injury caused by chest drainage: a case report

Surgical Case Reports ◽

10.1186/s40792-021-01215-6 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Hironori Oyamatsu ◽

Hideki Tsubouchi ◽

Kunio Narita

Keyword(s):

Lung Injury ◽

Chest Tube ◽

Drain Tube ◽

Chest Drainage ◽

Respiratory Condition ◽

Penrose Drain ◽

Multiple Rib Fractures ◽

Lung Injuries ◽

The Right ◽

Damaged Vessel

Abstract Background Pulmonary tractotomy effectively treats deep pulmonary penetrating injuries; however, it requires the accurate insertion of forceps or a stapler into the wound tract. This report describes a case of tractotomy using the Penrose drain guide for a deep lung injury caused by chest drainage. Case presentation A 75-year-old man suffered multiple rib fractures and hemothorax. After admission, chest tube drainage was performed because the patient’s respiratory condition deteriorated due to increased right pleural effusion. However, as the chest tube was stabbing into the right upper lobe, a pulmonary tractotomy was performed to treat the injury. Cutting the visceral pleura just over the tip of the chest tube caused the tube to completely penetrate the lung. A Penrose drain tube was fixed to the chest tube, which was then removed. The Penrose drain tube completely penetrated the lung and was coupled to the anvil side of the stapler to guide it smoothly into the wound tract. After stapling left the wound tract open, selective suture ligation of the damaged vessel and bronchioles was performed. Conclusions Although the indications for tractotomy using the Penrose drain guide are limited, we believe that this technique can be useful in patients with deep stabbing or penetrating lung injuries with rod- or tube-shaped foreign body remnants.

Download Full-text

Simulated aeromedical evacuation exacerbates burn induced lung injury: targeting mitochondrial DNA for reversal

Military Medical Research ◽

10.1186/s40779-021-00320-9 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Meng-Jing Xiao ◽

Xiao-Fang Zou ◽

Bin Li ◽

Bao-Long Li ◽

Shi-Jian Wu ◽

...

Keyword(s):

Lung Injury ◽

Nlrp3 Inflammasome ◽

Hypobaric Hypoxia ◽

Dnase I ◽

Treatment Intervention ◽

Aeromedical Evacuation ◽

Hypoxia Exposure ◽

Histopathological Evaluation ◽

Lung Injuries ◽

Mda Content

Abstract Background Aeromedical evacuation of patients with burn trauma is an important transport method in times of peace and war, during which patients are exposed to prolonged periods of hypobaric hypoxia; however, the effects of such exposure on burn injuries, particularly on burn-induced lung injuries, are largely unexplored. This study aimed to determine the effects of hypobaric hypoxia on burn-induced lung injuries and to investigate the underlying mechanism using a rat burn model. Methods A total of 40 male Wistar rats were randomly divided into four groups (10 in each group): sham burn (SB) group, burn in normoxia condition (BN) group, burn in hypoxia condition (BH) group, and burn in hypoxia condition with treatment intervention (BHD) group. Rats with 30% total body surface area burns were exposed to hypobaric hypoxia (2000 m altitude simulation) or normoxia conditions for 4 h. Deoxyribonuclease I (DNase I) was administered systemically as a treatment intervention. Systemic inflammatory mediator and mitochondrial deoxyribonucleic acid (mtDNA) levels were determined. A histopathological evaluation was performed and the acute lung injury (ALI) score was determined. Malonaldehyde (MDA) content, myeloperoxidase (MPO) activity, and the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome level were determined in lung tissues. Data among groups were compared using analysis of variance followed by Tukey’s test post hoc analysis. Results Burns resulted in a remarkably higher level of systemic inflammatory cytokines and mtDNA release, which was further heightened by hypobaric hypoxia exposure (P < 0.01). Moreover, hypobaric hypoxia exposure gave rise to increased NLRP3 inflammasome expression, MDA content, and MPO activity in the lung (P < 0.05 or P < 0.01). Burn-induced lung injuries were exacerbated, as shown by the histopathological evaluation and ALI score (P < 0.01). Administration of DNase I markedly reduced mtDNA release and systemic inflammatory cytokine production. Furthermore, the NLRP3 inflammasome level in lung tissues was decreased and burn-induced lung injury was ameliorated (P < 0.01). Conclusions Our results suggested that simulated aeromedical evacuation further increased burn-induced mtDNA release and exacerbated burn-induced inflammation and lung injury. DNase I reduced the release of mtDNA, limited mtDNA-induced systemic inflammation, and ameliorated burn-induced ALI. The intervening mtDNA level is thus a potential target to protect from burn-induced lung injury during aeromedical conditions and provides safer air evacuations for severely burned patients.

Download Full-text

Mechanism of protective effect of xuan-bai-cheng-qi decoction on LPS-induced acute lung injury based on an integrated network pharmacology and RNA-sequencing approach

Respiratory Research ◽

10.1186/s12931-021-01781-1 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Huahe Zhu ◽

Shun Wang ◽

Cong Shan ◽

Xiaoqian Li ◽

Bo Tan ◽

...

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Rna Sequencing ◽

Target Genes ◽

Mammalian Target Of Rapamycin ◽

Network Pharmacology ◽

Protective Mechanism ◽

Rna Seq ◽

Active Components ◽

Integrated Network

AbstractXuan-bai-cheng-qi decoction (XCD), a traditional Chinese medicine (TCM) prescription, has been widely used to treat a variety of respiratory diseases in China, especially to seriously infectious diseases such as acute lung injury (ALI). Due to the complexity of the chemical constituent, however, the underlying pharmacological mechanism of action of XCD is still unclear. To explore its protective mechanism on ALI, firstly, a network pharmacology experiment was conducted to construct a component-target network of XCD, which identified 46 active components and 280 predicted target genes. Then, RNA sequencing (RNA-seq) was used to screen differentially expressed genes (DEGs) between ALI model rats treated with and without XCD and 753 DEGs were found. By overlapping the target genes identified using network pharmacology and DEGs using RNA-seq, and subsequent protein–protein interaction (PPI) network analysis, 6 kernel targets such as vascular epidermal growth factor (VEGF), mammalian target of rapamycin (mTOR), AKT1, hypoxia-inducible factor-1α (HIF-1α), and phosphoinositide 3-kinase (PI3K) and gene of phosphate and tension homology deleted on chromsome ten (PTEN) were screened out to be closely relevant to ALI treatment. Verification experiments in the LPS-induced ALI model rats showed that XCD could alleviate lung tissue pathological injury through attenuating proinflammatory cytokines release such as tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β. Meanwhile, both the mRNA and protein expression levels of PI3K, mTOR, HIF-1α, and VEGF in the lung tissues were down-regulated with XCD treatment. Therefore, the regulations of XCD on PI3K/mTOR/HIF-1α/VEGF signaling pathway was probably a crucial mechanism involved in the protective mechanism of XCD on ALI treatment.

Download Full-text

LGG-31. CHARACTERIZING TEMPORAL GENOMIC HETEROGENEITY IN PEDIATRIC LOW GRADE GLIOMAS: ANALYSIS OF AN EXPANDED MULTI-INSTITUTIONAL COHORT WITH 101 PAIRED TUMOR SAMPLES

Neuro-Oncology ◽

10.1093/neuonc/noaa222.413 ◽

2020 ◽

Vol 22 (Supplement_3) ◽

pp. iii372-iii372

Author(s):

Margot A Lazow ◽

Austin Schafer ◽

Mariko D DeWire-Schottmiller ◽

Adam Lane ◽

Daniel R Boué ◽

...

Keyword(s):

Genetic Alterations ◽

Rapid Progression ◽

Low Grade ◽

Valuable Insight ◽

Histologic Diagnosis ◽

Low Grade Gliomas ◽

Genomic Landscape ◽

Cdkn2a Deletion ◽

Diagnostic Biopsy ◽

Over Time

Abstract INTRODUCTION Recent discoveries have provided valuable insight into the genomic landscape of pediatric low grade gliomas (LGGs) at diagnosis, facilitating molecularly targeted treatment. However, little is known about their temporal and therapy-related genomic heterogeneity. An adequate understanding of the evolution of pediatric LGGs’ genomic profiles over time is critically important in guiding decisions about targeted therapeutics and diagnostic biopsy at recurrence. METHODS Fluorescence in situ hybridization, mutation-specific immunohistochemistry, and exome analyses were performed on paired tumor samples from primary diagnostic and subsequent surgeries. RESULTS 101 tumor samples from 48 patients (43 with 2 specimens, 5 with 3 specimens) from 3 institutions underwent testing. BRAF fusion and BRAFV600E status were conserved in 100% and 97% of paired specimens, respectively. No loss or gain of IDH1 mutations or FGFR1, NTRK2, MYB, or MYBL1 rearrangements were detected over time. Histologic diagnosis remained the same in all tumors, with no acquired H3K27M mutations or malignant transformation. CDKN2A deletions were acquired in 7 patients (including 3 who received chemotherapy [2 with temozolomide] and 1 who received radiation), and were associated with a trend toward shorter time to progression (median: 5.5 vs. 13.0 months [p=0.08]). CONCLUSIONS Most targetable genetic alterations in pediatric LGGs, including BRAF alterations, are conserved at recurrence and following chemotherapy or radiation. However, CDKN2A deletion acquisition was demonstrated and may define a higher risk group. Given potential for targeted therapies for tumors acquiring CDKN2A deletions, performing a biopsy at recurrence may be indicated in certain patients, especially those with rapid progression.

Download Full-text