Assessment of the Suitability of the Fleischner Society Imaging Guidelines in Evaluating Chest Radiographs of COVID-19 Patients

Background@#The Fleischner Society established consensus guidelines for imaging in patients with coronavirus disease 2019 (COVID-19). We investigated the prevalence of pneumonia and the adverse outcomes by dividing groups according to the symptoms and risk factors of patients and assessed the suitability of the Fleischner society imaging guidelines in evaluating chest radiographs of COVID-19 patients. @*Methods@#From February 2020 to May 2020, 685 patients (204 males, mean 58 ± 17.9 years) who were diagnosed with COVID-19 and hospitalized were included. We divided patients into four groups according to the severity of symptoms and presence of risk factors (age > 65 years and presence of comorbidities). The patient groups were defined as follows: group 1 (asymptomatic patients), group 2 (patients with mild symptoms without risk factors), group 3 (patients with mild symptoms and risk factors), and group 4 (patients with moderate to severe symptoms). According to the Fleischner society, chest imaging is not indicated for groups 1–2 but is indicated for groups 3–4. We compared the prevalence and score of pneumonia on chest radiographs and compare the adverse outcomes (progress to severe pneumonia, intensive care unit admission, and death) between groups. @*Results@#Among the 685 COVID-19 patients, 138 (20.1%), 396 (57.8%), 102 (14.9%), and 49 (7.1%) patients corresponded to groups 1 to 4, respectively. Patients in groups 3–4 were significantly older and showed significantly higher prevalence rates of pneumonia (group 1–4: 37.7%, 51.3%, 71.6%, and 98%, respectively, P < 0.001) than those in groups 1-2. Adverse outcomes were also higher in groups 3–4 than in groups 1–2 (group 1–4: 8.0%, 3.5%, 6.9%, and 51%, respectively, P < 0.001). Patients with adverse outcomes in group 1 were initially asymptomatic but symptoms developed during follow-up. They were older (mean age, 80 years) and most of them had comorbidities (81.8%). Consistently asymptomatic patients had no adverse events. @*Conclusion@#The prevalence of pneumonia and adverse outcomes were different according to the symptoms and risk factors in COVID-19 patients. Therefore, as the Fleischner Society recommended, evaluation and monitoring of COVID-19 pneumonia using chest radiographs is necessary for old symptomatic patients with comorbidities.

Carnitine Orotate Complex Ameliorates Insulin Resistance and Hepatic Steatosis Through Carnitine Acetyltransferase Pathway

Background@#Carnitine orotate complex (Godex) has been shown to decrease glycated hemoglobin levels and improve steatosis in patients with type 2 diabetes mellitus with non-alcoholic fatty liver disease. However, the mechanisms of Godex in glucose metabolism remain unclear. @*Methods@#Male C57BL/6J mice were divided into four groups: normal-fat diet, high-fat diet, a high-fat diet supplemented with intraperitoneal injection of (500 mg or 2,000 mg/kg/day) Godex for 8 weeks. Computed tomography, indirect calorimetry, and histological analyses including electron microscopy of the liver were performed, and biochemical profiles and oral glucose tolerance test and insulin tolerance test were undertaken. Expressions of genes in the lipid and glucose metabolism, activities of oxidative phosphorylation enzymes, carnitine acetyltransferase, pyruvate dehydrogenase, and acetyl-coenzyme A (CoA)/CoA ratio were evaluated. @*Results@#Godex improved insulin sensitivity and significantly decreased fasting plasma glucose, homeostatic model assessment for insulin resistance, steatosis, and gluconeogenesis, with a marked increase in fatty acid oxidation as well as better use of glucose in high-fat diet-fed mice. It preserved mitochondrial function and ultrastructure, restored oxidative phosphorylation enzyme activities, decreased acetyl-CoA/CoA ratio, and increased carnitine acetyltransferase content and pyruvate dehydrogenase activity. Carnitine acetyltransferase knockdown partially reversed the effects of Godex in liver and in vitro. @*Conclusion@#Godex improved insulin resistance and steatosis by regulating carnitine acetyltransferase in liver in high-fat diet-fed mice.

Volume and Mass Doubling Time of Lung Adenocarcinoma according to WHO Histologic Classification

Objective@#This study aimed to evaluate the tumor doubling time of invasive lung adenocarcinoma according to the International Association of the Study for Lung Cancer (IASLC)/American Thoracic Society (ATS)/European Respiratory Society (ERS) histologic classification. @*Materials and Methods@#Among the 2905 patients with surgically resected lung adenocarcinoma, we retrospectively included 172 patients (mean age, 65.6 ± 9.0 years) who had paired thin-section non-contrast chest computed tomography (CT) scans at least 84 days apart with the same CT parameters, along with 10 patients with squamous cell carcinoma (mean age, 70.9 ± 7.4 years) for comparison. Three-dimensional semiautomatic segmentation of nodules was performed to calculate the volume doubling time (VDT), mass doubling time (MDT), and specific growth rate (SGR) of volume and mass. Multivariate linear regression, one-way analysis of variance, and receiver operating characteristic curve analyses were performed. @*Results@#The median VDT and MDT of lung cancers were as follows: acinar, 603.2 and 639.5 days; lepidic, 1140.6 and 970.1 days; solid/micropapillary, 232.7 and 221.8 days; papillary, 599.0 and 624.3 days; invasive mucinous, 440.7 and 438.2 days; and squamous cell carcinoma, 149.1 and 146.1 days, respectively. The adjusted SGR of volume and mass of the solid-/ micropapillary-predominant subtypes were significantly shorter than those of the acinar-, lepidic-, and papillary-predominant subtypes. The histologic subtype was independently associated with tumor doubling time. A VDT of 465.2 days and an MDT of 437.5 days yielded areas under the curve of 0.791 and 0.795, respectively, for distinguishing solid-/micropapillary-predominant subtypes from other subtypes of lung adenocarcinoma. @*Conclusion@#The tumor doubling time of invasive lung adenocarcinoma differed according to the IASCL/ATS/ERS histologic classification.

2020 Clinical Practice Guideline for Percutaneous Transthoracic Needle Biopsy of Pulmonary Lesions: A Consensus Statement and Recommendations of the Korean Society of Thoracic Radiology

Percutaneous transthoracic needle biopsy (PTNB) is one of the essential diagnostic procedures for pulmonary lesions. Its role is increasing in the era of CT screening for lung cancer and precision medicine. The Korean Society of Thoracic Radiology developed the first evidence-based clinical guideline for PTNB in Korea by adapting pre-existing guidelines. The guideline provides 39 recommendations for the following four main domains of 12 key questions: the indications for PTNB, pre-procedural evaluation, procedural technique of PTNB and its accuracy, and management of post-biopsy complications. We hope that these recommendations can improve the diagnostic accuracy and safety of PTNB in clinical practice and promote standardization of the procedure nationwide.

Incremental Image Noise Reduction in Coronary CT Angiography Using a Deep Learning-Based Technique with Iterative Reconstruction

Objective@#To assess the feasibility of applying a deep learning-based denoising technique to coronary CT angiography (CCTA) along with iterative reconstruction for additional noise reduction. @*Materials and Methods@#We retrospectively enrolled 82 consecutive patients (male:female = 60:22; mean age, 67.0 ± 10.8 years) who had undergone both CCTA and invasive coronary artery angiography from March 2017 to June 2018. All included patients underwent CCTA with iterative reconstruction (ADMIRE level 3, Siemens Healthineers). We developed a deep learning based denoising technique (ClariCT.AI, ClariPI), which was based on a modified U-net type convolutional neural net model designed to predict the possible occurrence of low-dose noise in the originals. Denoised images were obtained by subtracting the predicted noise from the originals. Image noise, CT attenuation, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were objectively calculated. The edge rise distance (ERD) was measured as an indicator of image sharpness. Two blinded readers subjectively graded the image quality using a 5-point scale. Diagnostic performance of the CCTA was evaluated based on the presence or absence of significant stenosis (≥ 50% lumen reduction). @*Results@#Objective image qualities (original vs. denoised: image noise, 67.22 ± 25.74 vs. 52.64 ± 27.40; SNR [left main], 21.91 ± 6.38 vs. 30.35 ± 10.46; CNR [left main], 23.24 ± 6.52 vs. 31.93 ± 10.72; all p < 0.001) and subjective image quality (2.45 ± 0.62 vs. 3.65 ± 0.60, p < 0.001) improved significantly in the denoised images. The average ERDs of the denoised images were significantly smaller than those of originals (0.98 ± 0.08 vs. 0.09 ± 0.08, p < 0.001). With regard to diagnostic accuracy, no significant differences were observed among paired comparisons. @*Conclusion@#Application of the deep learning technique along with iterative reconstruction can enhance the noise reduction performance with a significant improvement in objective and subjective image qualities of CCTA images.

The optimal surgical resection approach for T2 gallbladder carcinoma: evaluating the role of surgical extent according to the tumor location

PURPOSE: The clinical behavior of T2 gallbladder cancer varies among patients. The aims of this study were to identify prognostic factors for survival and recurrence, and to determine the optimal surgical strategy for T2 gallbladder cancer. METHODS: We conducted a retrospective analysis of 78 patients with T2 gallbladder cancer who underwent surgical resection for gallbladder cancer. RESULTS: Twenty-eight patients (35.9%) underwent simple cholecystectomy and 50 (64.1%) underwent extended cholecystectomy. Among 56 patients without LN metastasis (n = 20) or unknown LN status (no LN dissection, n = 36), the 5-year disease-free survival rates were 81.6%, and 69.8% (P = 0.080). In an analysis according to tumor location, patients with tumors located on the hepatic side (n = 36) had a higher recurrence rate than patients with tumors located on the peritoneal side only (n = 35) (P = 0.043). On multivariate analysis, R1 resection and lymph node metastasis were significant, independent prognostic factors for poor disease-free and overall survival. CONCLUSION: R0 resection and LN dissection are an appropriate curative surgical strategy in patients with T2 gallbladder cancer. Tumors located on the hepatic side show worse prognosis than tumors located on the peritoneal side only, hepatic resection should be considered.

Multicystic benign mesothelioma of the pelvic peritoneum presenting as acute abdominal pain in a young woman

Multicystic benign mesothelioma (MBM) of the peritoneum is a very rare condition. Since the first description of MBM in 1979, approximately 100 cases have been reported. This is a case report of MBM of the pelvic peritoneum presenting as acute abdominal pain in a young woman. Laparoscopy confirmed multiple grapelike clusters of cysts that originated in the peritoneum of the rectouterine pouch and histopathologic diagnosis was confirmed as MBM of the pelvic peritoneum. We hope to alert gynaecologists of the diagnostic and therapeutic approaches to MBM which can be accomplished by laparoscopy.

Effect of Vitamin E on Cadmium Accumulation and Excretion in Chronic Cadmium Poisoned Rats

The purpose of this study was to investigate the effect of vitamin E on the cadmium accumulation in body, cadmium excretion and detoxification functions in chronic cadmium poisoned rats. Sprague-Dawley male rats weighing 100+/-10 g were randomly assigned to one normal group and three cadmium poisoned groups. Cadmium poisoned groups were classified to vitamin E free diet (Cd-0E group), vitamin E 40 mg/kg diet (Cd-400E group) and 400 mg/kg diet (Cd-400E group) according to the levels of vitamin E supplement. Animals were maintained on 0, 40 mg and 400 mg vitamin E/kg diets for 20 weeks and simultaneously administered 50 ppm Cd2+ dissolved in the drinking water. Body weight, food intakes and food efficiency ratio were significantly decreased in all cadmium groups, compared with those of normal group. The accumulation of cadmium in rat liver, kidney and blood was reduced by sufficient vitamin E supplementation. The metallothionein (MT) content in liver and kidney were increased in all cadmium groups compared with that of normal group. The ratio of cadmium absorption and retention were significantly decreased in vitamin E supplementation groups. Accordingly, vitamin E supplementation resulted in an excretion of cadmium in urine and feces and a lowered accumulation of cadmium in liver and kidney. It can be suggested that increased MT synthesis lead to the significant decrease in cadmium absorption and retention rations.

Diminished vascular guanylyl cyclase activity in deoxycorticosterone acetate-salt hypertension

Pathophysiological implications of the vascular nitric oxide (NO)/cGMP pathway in hypertension were investigated. Sprague-Dawley rats were made deoxycorticosterone acetate (DOCA)-salt hypertensive for six weeks. The protein expression of endothelial constitutive NO synthase (ecNOS) and the tissue content of NO were determined in the thoracic aorta. The protein expression and catalytic activity of soluble guanylyl cyclase (GC) were also determined. Systolic blood pressure measured on the day of experiment was significantly higher in the experimental group than in the control. The hypertension was associated with decreases in the vascular tissue content of NO metabolites, concomitantly with the expression of ecNOS proteins. The protein expression of GC was not affected, while its catalytic activity was significantly decreased in hypertension. These results indicate that the high blood pressure is associated with a decreased activity of vascular NO/cGMP pathway in DOCA-salt hypertension.

Cysteine carboxyl O-methylation of human placental 23 kDa protein

C-Terminal carboxyl methylation of a human placental 23 kDa protein catalyzed by membrane-associated methyltransferase has been investigated. The 23 kDa protein substrate methylated was partially purified by DEAE-Sephacel, hydroxyapatite and Sephadex G-100 gel filtration chromatographies. The substrate protein was eluted on Sephadex G-100 gel filtration chromatography as a protein of about 29 kDa. In the absence of Mg2+, the methylation was stimulated by guanine nucleotides (GTP, GDP and GTPgammaS), but in the presence of Mg2+, only GTPgammaS stimulated the methylation which was similar to the effect on the G25K/rhoGDI complex. AFC, an inhibitor of C-terminal carboxyl methylation, inhibited the methylation of human placental 23 kDa protein. These results suggests that the substrate is a small G protein different from the G25K and is methylated on C-terminal isoprenylated cysteine residue. This was also confirmed by vapor phase analysis. The methylated substrate protein was redistributed to membrane after in vitro methylation, suggesting that the methylation of this protein is important for the redistribution of the 23 kDa small G protein for its putative role in intracellular signaling.

Protein methylation in cellular proliferation and differentiation: Non-histone nuclear methyl acceptor protein(s) during 3'-methyl-4-dimethylaminoazobenzeneinduced hepatocarcinogenesis

An accelerating effect of methyl-deficient diet (MDD) on hepatocarcinogenesis and methylation pattern of nuclear protein(s) by S-adenosylmethionine: protein arginine N-methyltransferase (protein methylase I, PM-I) have been studied with 3'-methyl-4-dimethyl- aminoazobenzene(MeDAB)-treated rats. The MDD+MeDAB-fed group produced typical cancer cells in the liver almost two weeks earlier than the control synthetic diet (CSD)+MeDAB-fed group. Protein methylase I (PM-I) activity in the livers of MDD alone fed rats began to increase at around 2 weeks after MDD-feeding, reaching a peak at 4 weeks and declining thereafter. When nuclei isolated either from normal livers or from cholangiocarcinoma cells were incubated with PM-I preparation from normal liver, 16 and 23-kDa nuclear proteins were the major methylated proteins, regardless of the source of the nuclei. However, when the above mentioned nuclei were incubated with PM-I preparations either from MDD alone fed livers or MDD+ MeDAB-induced cholangiocarcinoma cells, the methylation of 23-kDa protein was not detected. The result suggests that there is a hitherto-unknown PM-I specific to 23 kDa nuclear protein which was lost during methyl deficient diet feeding and hepatocarcinogenesis. The N-terminal 20 amino acids sequence of the 23-kDa protein was found to be (1)Gly-Val-Pro-Leu-(5)X-Arg-Leu-Phe-Asp-(10)His-Ala-Met-Leu-Gln-(15)Ala -His-Arg-Ala-His-(20)Glu, having 94.7% sequence homology with human chorionic somatomammotropin precursor A and B.