Predicting Postoperative Lung Function in Patients with Lung Cancer Using Imaging Biomarkers.

There have been previous studies conducted to predict postoperative lung function with pulmonary function tests (PFTs). Computing tomography (CT) can quantitatively measure small airway walls' thickness, lung volume, pulmonary vessel volume, and emphysema area, which reflect the severity of respiratory diseases. These measurements are considered imaging biomarkers. This study aimed to predict postoperative lung function with imaging biomarkers. A retrospective analysis of 79 patients with lung cancer who had undergone lung surgery was completed. Postoperative lung function measured by forced expiratory volume in one second (FEV1) was defined as an outcome. Preoperative clinico-pathological parameters and imaging biomarkers representing airway walls' thickness, severity of emphysema, total lung volume, and pulmonary vessel volume were measured quantitatively in chest CT by an automated segmentation software, AVIEW COPD. Pi1 was defined as the first percentile along the histogram of lung attenuation that represents the degree of emphysema. Wafw was defined as the airway thickness, which was calculated by the full-width at half-maximum method. Logistic and linear regressions were used to assess these variables. If the actual postoperative FEV1 was higher than the postoperative FEV1 projected by a formula, the group was considered to be preserved. Among the 79 patients, 16 of the patients were grouped as a non-preserved group, and 63 of them were grouped as a preserved group. The patients in the preserved FEV1 group had a higher vessel volume than the non-preserved group. Pi1 and Wafw were independent predictors of postoperative lung function. Imaging biomarkers can be considered significant variables in predicting postoperative lung function in patients with lung cancer.

DOT1L is critical for adult vessel maintenance and functions.

Objective: DOT1L is the only known histone H3K79 methyltransferase essential for the development of the embryonic cardiovascular system, including the heart, blood vessels, and lymphatic vessels, through transcriptional regulation. Our previous study demonstrated that Dot1l deletion results in aberrant lymphatic development and function. However, its precise function in the postnatal cardiovascular system remains unknown. Methods: Using conditional and inducible Dot1l knockout (KO) mice, along with a reporter strain carrying the Geo gene at the Dot1l locus, DOT1L expression and its function in the vascular system during postnatal life were investigated. To assess vessel morphology and vascular permeability, we administered Latex or Evans blue dye to KO mice. In addition, in vitro tube formation and cell migration assays were performed using DOT1L-depleted human umbilical vein endothelial cells (HUVECs). Changes in the expression of vascular genes in HUVECs were measured by quantitative polymerase chain reaction. Results: Our findings demonstrate that conditional Dot1l knockout in the Tg (Tie2-cre) strain results in abnormal blood vessel formation and lymphatic anomalies in the intestine. In a mouse model of Rosa26-creER-mediated inducible Dot1l knockout, we observed vascular phenotypes, including increased vascular permeability and brain hemorrhage, when DOT1L was deleted in adulthood. Additionally, DOT1L depletion in cultured HUVECs led to impaired cell migration and tube formation, likely due to altered gene transcription. These findings highlight the essential role of DOT1L in maintaining vascular integrity and function during embryonic development and postnatal life. Conclusion: Our study revealed that DOT1L is required for the maintenance of adult vascular function through the regulation of gene expression.

RNA helicase DEAD-box-5 is involved in R-loop dynamics of preimplantation embryos.

OBJECTIVE: R-loops are DNA:RNA triplex hybrids, and their metabolism is tightly regulated by transcriptional regulation, DNA damage response, and chromatin structure dynamics. R-loop homeostasis is dynamically regulated and closely associated with gene transcription in mouse zygotes. However, the factors responsible for regulating these dynamic changes in the R-loops of fertilized mouse eggs have not yet been investigated. This study examined the functions of candidate factors that interact with R-loops during zygotic gene activation. METHODS: In this study, we used publicly available next-generation sequencing datasets, including low-input ribosome profiling analysis and polymerase II chromatin immunoprecipitation-sequencing (ChIP-seq), to identify potential regulators of R-loop dynamics in zygotes. These datasets were downloaded, reanalyzed, and compared with mass spectrometry data to identify candidate factors involved in regulating R-loop dynamics. To validate the functions of these candidate factors, we treated mouse zygotes with chemical inhibitors using in vitro fertilization. Immunofluorescence with an anti-R-loop antibody was then performed to quantify changes in R-loop metabolism. RESULTS: We identified DEAD-box-5 (DDX5) and histone deacetylase-2 (HDAC2) as candidates that potentially regulate R-loop metabolism in oocytes, zygotes and two-cell embryos based on change of their gene translation. Our analysis revealed that the DDX5 inhibition of activity led to decreased R-loop accumulation in pronuclei, indicating its involvement in regulating R-loop dynamics. However, the inhibition of histone deacetylase-2 activity did not significantly affect R-loop levels in pronuclei. CONCLUSION: These findings suggest that dynamic changes in R-loops during mouse zygote development are likely regulated by RNA helicases, particularly DDX5, in conjunction with transcriptional processes. Our study provides compelling evidence for the involvement of these factors in regulating R-loop dynamics during early embryonic development.

The Value of Residual Volume/Total Lung Capacity as an Indicator for Predicting Postoperative Lung Function in Non-Small Lung Cancer.

Chronic obstructive pulmonary disease (COPD) is one of the most frequently occurring concomitant diseases in patients with non-small cell lung cancer (NSCLC). It is characterized by small airways and the hyperinflation of the lung. Patients with hyperinflated lung tend to have more reserved lung function than conventionally predicted after lung cancer surgery. The aim of this study was to identify other indicators in predicting postoperative lung function after lung resection for lung cancer. Patients with NSCLC who underwent curative lobectomy with mediastinal lymph node dissection from 2017 to 2019 were included. Predicted postoperative FEV1 (ppoFEV1) was calculated using the formula: preoperative FEV1 × (19 segments-the number of segments to be removed) ÷ 19. The difference between the measured postoperative FEV1 and ppoFEV1 was defined as an outcome. Patients were categorized into two groups: preserved FEV1 if the difference was positive and non-preserved FEV1, if otherwise. In total, 238 patients were included: 74 (31.1%) in the FEV1 non-preserved group and 164 (68.9%) in the FEV1 preserved group. The proportion of preoperative residual volume (RV)/total lung capacity (TLC) ≥ 40% in the FEV1 non-preserved group (21.4%) was lower than in the preserved group (36.1%) (p = 0.03). In logistic regression analysis, preoperative RV/TLC ≥ 40% was related to postoperative FEV1 preservation. (adjusted OR, 2.02, p = 0.041). Linear regression analysis suggested that preoperative RV/TLC was positively correlated with a significant difference. (p = 0.004) Preoperative RV/TLC ≥ 40% was an independent predictor of preserved lung function in patients undergoing curative lobectomy with mediastinal lymph node dissection. Preoperative RV/TLC is positively correlated with postoperative lung function.

Hepatogastric fistula as a rare complication of pyogenic liver abscess.

Hepatogastric fistula following a pyogenic liver abscess is extremely rare, and only a handful of cases have been reported. An 88-year-old female presented with generalized weakness, fever and chills. An abdominal computed tomography scan revealed a 5cm-sized hypodense lesion with internal septa in the left lateral section of the liver. Due to initial suspicion of early liver abscess, she was treated with empirical intravenous antibiotics. Initially, aspiration or drainage of the liver abscess was not performed due to immature lesion characteristics. An ultrasonography-guided percutaneous drainage of the liver abscess was performed 17 days after hospitalization due to a more mature lesion appearance on follow-up imaging. On tubography, contrast media leakage through the fistulous tract was visualized. Surgical management was performed, and she was discharged 2 weeks after surgery.