Cerebrospinal fluid flow artifact reduction with deep learning to optimize the evaluation of spinal canal stenosis on spine MRI.

PURPOSE: The aim of study was to employ the Cycle Generative Adversarial Network (CycleGAN) deep learning model to diminish the cerebrospinal fluid (CSF) flow artifacts in cervical spine MRI. We also evaluate the agreement in quantifying spinal canal stenosis. METHODS: For training model, we collected 9633 axial MR image pairs from 399 subjects. Then, additional 104 image pairs from 19 subjects were gathered for the test set. The deep learning model was developed using CycleGAN to reduce CSF flow artifacts, where T2 TSE images served as input, and T2 FFE images, known for fewer CSF flow artifacts. Post training, CycleGAN-generated images were subjected to both quantitative and qualitative evaluations for CSF artifacts. For assessing the agreement of spinal canal stenosis, four raters utilized an additional 104 pairs of original and CycleGAN-generated images, with inter-rater agreement evaluated using a weighted kappa value. RESULTS: CSF flow artifacts were reduced in the CycleGAN-generated images compared to the T2 TSE and FFE images in both quantitative and qualitative analysis. All raters concordantly displayed satisfactory estimation results when assessing spinal canal stenosis using the CycleGAN-generated images with T2 TSE images (kappa = 0.61-0.75) compared to the original FFE with T2 TSE images (kappa = 0.48-0.71). CONCLUSIONS: CycleGAN demonstrated the capability to produce images with diminished CSF flow artifacts. When paired with T2 TSE images, the CycleGAN-generated images allowed for more consistent assessment of spinal canal stenosis and exhibited agreement levels that were comparable to the combination of T2 TSE and FFE images.

Effect of belimumab in patients with systemic lupus erythematosus treated with low dose or no corticosteroids.

BACKGROUND/AIMS: Systemic lupus erythematosus (SLE) responder index (SRI)-4 response has been achieved with belimumab treatment in patients with moderate disease activity in cornerstone clinical trials and following studies. However, most studies involved patients treated with a mean prednisolone-equivalent dose of approximately 10 mg/d and focused on the steroid-sparing effect of belimumab. We aimed to identify the effect of belimumab in patients with mild-to-moderate SLE who were treated with low-dose or no corticosteroids. METHODS: We retrospectively reviewed the electronic medical records of patients treated with belimumab for at least 6 months between May 2021 and June 2022. The primary endpoint was SRI-4 response at 6 months. RESULTS: Thirty-one patients were included (13 low dose- and 18 steroid non-users). The mean age was 39.2 ± 11.4 years, and 90.3% of patients were female. The baseline Safety of Estrogens in Lupus Erythematosus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) score was 6.0 (4.0-9.0). The primary endpoint was achieved in 32.3% (10/31) of patients. Significant improvements in anemia, C4 levels, and SELENA-SLEDAI score were observed during treatment. Univariate analysis showed that the baseline SELENA-SLEDAI and arthritis were significantly associated with SRI-4 response at 6 months, and only the SELENA-SLEDAI remained significant (p = 0.014) in multivariate analysis. CONCLUSION: This cohort study is the first to report the efficacy of belimumab after minimizing the effect of corticosteroids. Belimumab showed efficacy in improving the SELENA-SLEDAI score, anemia, and low C4 in patients who did not receive corticosteroids or received only low doses.

Relapse in patients with antineutrophil cytoplasmic antibody-associated vasculitis undergoing dialysis: a single-centre retrospective study in South Korea.

OBJECTIVES: The disease activity of antineutrophil cytoplasmic antibody-associated vasculitis (AAV) can decrease after dialysis, and relapse after dialysis is not well-studied. We investigated the clinical manifestations and factors associated with relapse in patients with AAV undergoing dialysis. METHODS: This retrospective study included data of patients with AAV undergoing dialysis due to renal involvement from July 2005 to March 2021 in a single tertiary centre in Seoul, Korea. Cox regression analysis was performed to identify relapse-associated factors. RESULTS: The study cohort included 38 patients with a median age of 64.0 years; 28 (73.7%) were female, and 35 (92.1%) patients were diagnosed with microscopic polyangiitis (MPA). At diagnosis, the mean Birmingham vasculitis activity score (BVAS) was 18.3 and 66.3% of the patients exhibited pulmonary manifestations. During follow-up, 12 patients experienced AAV relapse, including nine patients with diffuse alveolar haemorrhage (DAH), two patients with aggravated interstitial lung disease, and one patient with DAH accompanied with neuropathy. Clinical features including age, sex, and baseline BVAS did not significantly differ between the relapse and non-relapse groups. By univariable analysis, lung infiltration, DAH, corticosteroid pulse therapy for induction, and mean corticosteroid dose were significantly associated with relapse. Multivariable analysis revealed that DAH (adjusted hazard ratio 5.509, 95% CI 1.569-19.339; P=0.008) and mean corticosteroid dose (adjusted hazard ratio 1.381, 95% CI 1.161-1.642; P<0.001) were significantly associated with relapse. CONCLUSIONS: In patients with AAV undergoing dialysis, DAH and mean corticosteroid dose were significantly associated with relapse, highlighting the importance of close monitoring.

Fat quantification of the rotator cuff muscles using CT histogram analysis in comparison with Dixon MRI sequence.

OBJECTIVES: To quantify the proportion of fat within the rotator cuff muscles using CT histogram analysis (HA) and to compare fat fraction (FF) values obtained from CT and T2*-corrected 6-echo three-dimensional gradient-echo Dixon sequences. METHODS: Twenty-six patients who underwent both shoulder CT and MRI were enrolled. The FF of rotator cuff muscles was measured on FF maps of the Dixon technique. Using CT, the FF values were obtained in two ways: 1) CT mean Hounsfield Unit (HU) measurement-based fat quantification using subcutaneous fat and the teres major muscle as internal standards; and 2) CT HA-based fat quantification in which pixels from -190 to -30 HU were arbitrarily classified as fat, and those from -30 to 150 HU as muscle. Afterward, the relationship between FF values from MRI (FF-MR), CT mean HU-based analysis (FF-HU), and CT HA (FF-HA) was assessed. RESULTS: There were strong positive correlations (p < 0.001) between FF-MR and FF-HA, which were higher when compared with FF-HU (r = 0.90 vs. 0.77 for total). For a total of 104 rotator cuff muscles, the intraclass correlation between FF-MR and FF-HA was excellent (ICC, 0.90), which was higher than that between FF-MR and FF-HU (ICC, 0.76). The ICCs showed excellent interobserver agreement between FF-MR, FF-HU, and FF-HA (ICCs, 0.93-0.96). CONCLUSIONS: Fat quantification within the rotator cuff muscles using CT HA is both feasible and reliable. ADVANCES IN KNOWLEDGE: CT HA provides reliable quantification of intramuscular fat and has strengths regarding its retrospective applicability to conventional CT studies without additional radiation dose to subjecting patients.

Recovery and long-term renal outcome of patients with anti-neutrophil cytoplasmic antibody-associated vasculitis who are on dialysis at presentation.

Objective: Renal involvement in anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) can lead to severe renal dysfunction requiring dialysis at diagnosis. We aimed to study the clinical and pathologic characteristics of patients with AAV dependent on dialysis at presentation and the long-term renal outcomes of patients who recovered from dialysis. Methods: This retrospective study analyzed data of patients diagnosed with AAV who were on dialysis from July 2005 to May 2021 at a single tertiary center in Korea. Results: Thirty-four patients were included in the study (median age 64.5 years, females 61.8%), of which 13 discontinued and 21 continued dialysis. The proportion of normal glomeruli (p<0.001) and interstitial fibrosis (p=0.024) showed significant differences between both groups. Multivariable analysis showed that the proportion of normal glomeruli was associated with dialysis discontinuation (odds ratio=1.29, 95% confidence interval 0.99~1.68, p=0.063), although without statistical significance. Treatment modalities, including plasmapheresis, did not show significance with dialysis discontinuation. In the follow-up analysis of 13 patients who had discontinued dialysis for a median of 81 months, 12 did not require dialysis, and their glomerular filtration rate values significantly increased at follow-up time compared to when they stopped dialysis (37.5 [28.5~45.5] vs. 24.0 [18.5~30.0] mL/min/1.73 m²; p=0.008). Conclusion: Approximately 38% of AAV patients on dialysis discontinued dialysis, and the recovered patients had improved renal function without dialysis during longer follow-up. Patients with AAV on dialysis should be given the possibility of dialysis discontinuation and renal recovery, especially those with normal glomeruli in kidney pathology.

When MRI would be useful in patients without evidence of sacroiliitis on radiographs?

We aimed to identify when magnetic resonance imaging (MRI) would be useful to diagnose patients with suspected axial spondyloarthropathy (AxSpA) without evidence of sacroiliitis on radiographs. We retrospectively reviewed electronic medical records of patients who underwent pelvis MRI after radiographs at the rheumatology clinic in a single tertiary center in Korea. Patients underwent imaging from January 2020 to July 2022. We collected data including complete blood count, erythrocyte sedimentation rate, C-reactive protein (CRP), human leukocyte antigen (HLA)-B27, history of acute anterior uveitis (AAU), peripheral arthritis, dactylitis, inflammatory bowel disease (IBD), enthesopathy, and psoriasis. A total of 105 patients who showed no evidence of sacroiliitis on radiographs were included. The median age of patients was 41.0 years, and 44.8% were male. Of them, 34 showed sacroiliitis on MRI (group 1), and 71 showed no evidence of sacroiliitis even on MRI (group 2). Known AxSpA-related clinical features including AAU, peripheral arthritis, dactylitis, IBD, enthesopathy, and psoriasis were not different between the two groups. HLA-B27 positivity (79.4% vs. 40.0%, p < 0.001), median white blood cell count (7700 vs. 6300, p = 0.007), mean platelet count (307.7 ± 69.7 vs. 265.3 ± 68.9 × 103/µL, p = 0.005), and median CRP level (0.38 vs. 0.10, p = 0.001) showed significant differences between the two groups. In a multivariate analysis, HLA-B27 positivity and platelet count were significantly associated with sacroiliitis on MRI. In our cohort, sacroiliitis was observed on MRI in one-third of patients without radiographic evidence. MRI could be recommended to evaluate sacroiliitis in patients with positive HLA-B27 and a high platelet count.

Feasibility and clinical usefulness of deep learning-accelerated MRI for acute painful fracture patients wearing a splint: A prospective comparative study.

OBJECTIVE: To evaluate the feasibility and clinical usefulness of deep learning (DL)-accelerated turbo spin echo (TSEDL) sequences relative to standard TSE sequences (TSES) for acute radius fracture patients wearing a splint. METHODS: This prospective consecutive study investigated 50 patients' preoperative wrist MRI scans acquired between July 2021 and January 2022. Examinations were performed at 3 Tesla MRI with body array coils due to the wrist splint. Besides TSES obtained according to the routine protocol, TSEDL sequences for axial T2-, coronal T1-, and coronal PD-weighted TSE sequences were scanned for comparison. For quantitative assessment, the relative signal-to-noise ratio (rSNR), the relative contrast-to-noise ratio (rCNR), and the relative contrast ratio (rCR) were measured. For qualitative assessment, all images were assessed by two independent musculoskeletal radiologists in terms of perceived SNR, image contrast, image sharpness, artifacts disturbing evaluation, overall image quality and diagnostic confidence for injuries using a four- or five-point Likert scale. RESULTS: The scan time was shortened approximately by a factor of two for TSEDL compared to TSES. TSEDL images showed significantly better rSNR, rCNR, and rCR values for all sequences, and scored significantly better in terms of both image quality and diagnostic confidence for both readers than TSES images (all p < .05). Interrater reliabilities were in almost perfect agreement. CONCLUSION: The DL-accelerated technique proved to be very helpful not only to reduce scan time but also to improve image quality for acute painful fracture patients wearing a splint despite using body array coils instead of a wrist-specific coil. Based on our study, the DL-accelerated technique can be very useful for MRI of any part of the extremities in trauma settings just with body array coils.

Prognostic value of proteinuria monitoring in anti-neutrophil cytoplasmic antibody-associated vasculitis.

OBJECTIVE: To determine the prognostic significance of proteinuria monitoring in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV). METHODS: We retrospectively analyzed the data of kidney biopsy-confirmed patients with AAV. Proteinuria was evaluated by a urine dipstick test. Poor renal outcome was defined as stage 4/5 chronic kidney disease (CKD) (estimated glomerular filtration rate < 30 mL/min/1.73 m2). RESULTS: We enrolled 77 patients with a median follow-up duration of 36 months (interquartile range, 18-79) in this study. Excluding 8 patients on dialysis at 6 months, 59/69 (85.5%) achieved remission after induction therapy. Patients were then divided into two groups according to the presence of proteinuria at 6 months after induction therapy (n = 29 with proteinuria, 40 without proteinuria). There was no significant difference in the rate of relapse or death according to the presence of proteinuria (p = 0.304 relapse, 0.401 death). In contrast, patients with proteinuria had significantly lower kidney function than those without proteinuria (41 vs. 53.5 mL/min/1.73 m2, p = 0.003). Multivariate analysis revealed that eGFR values at 6 months (hazard ratio [HR] 0.925; 95% CI 0.875-0.978, p = 0.006) and proteinuria at 6 months (HR 4.613; 95% CI 1.230-17.298, p = 0.023) were significantly associated with stage 4/5 CKD. CONCLUSION: The presence of proteinuria at 6 months after induction therapy and low renal function was significantly associated with a higher risk of stage 4/5 CKD in patients with AAV. Monitoring for proteinuria after induction therapy may help predict poor renal outcomes in patients with AAV.

Past and Future Epidemiological Perspectives and Integrated Management of Rice Bakanae in Korea.

In the past, rice bakanae was considered an endemic disease that did not cause significant losses in Korea; however, the disease has recently become a serious threat due to climate change, changes in farming practices, and the emergence of fungicide-resistant strains. Since the bakanae outbreak in 2006, its incidence has gradually decreased due to the application of effective control measures such as hot water immersion methods and seed disinfectants. However, in 2013, a marked increase in bakanae incidence was observed, causing problems for rice farmers. Therefore, in this review, we present the potential risks from climate change based on an epidemiological understanding of the pathogen, host plant, and environment, which are the key elements influencing the incidence of bakanae. In addition, disease management options to reduce the disease pressure of bakanae below the economic threshold level are investigated, with a specific focus on resistant varieties, as well as chemical, biological, cultural, and physical control methods. Lastly, as more effective countermeasures to bakanae, we propose an integrated disease management option that combines different control methods, including advanced imaging technologies such as remote sensing. In this review, we revisit and examine bakanae, a traditional seed-borne fungal disease that has not gained considerable attention in the agricultural history of Korea. Based on the understanding of the present significance and anticipated risks of the disease, the findings of this study are expected to provide useful information for the establishment of an effective response strategy to bakanae in the era of climate change.

Risk of New-Onset Diabetes Mellitus Associated with Antirheumatic Drugs in Patients with Rheumatoid Arthritis: A Nationwide Population Study.

Background: This study aimed to investigate the effect of disease-modifying antirheumatic drugs (DMARDs) on diabetes mellitus (DM) development in rheumatoid arthritis (RA). Methods: This nested case−control study with a cohort of 69,779 DM-naïve adult patients with RA was conducted from 2011 to 2019 in South Korea. Cases with incident DM were identified and individually matched to randomly selected controls (1:4). DMARDs use was measured for 1 year before the index date and stratified by exposure duration. The association of each DMARD use with DM risk was estimated using conditional logistic regression adjusted for comorbidities and concomitant drug use. Results: Of the patients, 5.4% were newly diagnosed with DM. The use of statins and a higher cumulative dose of corticosteroids were associated with an increased DM risk. In a multivariable-adjusted analysis, cumulative duration of exposure (CDE) >270 days/year, hydroxychloroquine (HCQ; adjusted odds ratio [aOR], 0.76) and methotrexate (MTX; aOR, 0.81) were associated with a significant decrease in DM risk, and tacrolimus (TAC; aOR, 1.27) was associated with an increased risk. Conclusions: Long-term use of HCQ and MTX (>270 days/year) was associated with a reduction in DM incidence as opposed to TAC.

Identification of a new strain of ligustrum virus A causing leaf necrosis and chlorosis symptoms in Syringa oblata var. dilatata (Nakai) Rehder.

In 2020, lilac trees showing virus-like symptoms such as leaf necrosis and chlorosis were observed in Korea. After RT-PCR detection with specific primer sets designed based on previously reported nucleotide sequences of viruses in lilac, the agent was identified as ligustrum virus A (LVA). The complete genome of the virus was sequenced and used for phylogenetic analysis. The genome of this novel strain of LVA, LVA-SNU, is 8524 nucleotides long, excluding the poly(A) tail, and shares the highest nucleotide sequence identity (77.28%) with LVA-Sob, which was detected in a plant of the same species, Syringa oblata, in China, whereas LVA-Sob shares higher sequence identity (97.89%) with LVA-SK, which has been detected in host plants of various species.

Effectiveness of radiologist training in improving reader agreement for Lung-RADS 4X categorization.

OBJECTIVES: To identify the agreement on Lung CT Screening Reporting and Data System 4X categorization between radiologists and an expert-adjudicated reference standard and to investigate whether training led to improvement of the agreement measures and diagnostic potential for lung cancer. METHODS: Category 4 nodules in the Korean Lung Cancer Screening Project were identified retrospectively, and each 4X nodule was matched with one 4A or 4B nodule. An expert panel re-evaluated the categories and determined the reference standard. Nineteen radiologists were asked to determine the presence of CT features of malignancy and 4X categorization for each nodule. A review was performed in two sessions, and training material was given after session 1. Agreement on 4X categorization between radiologists and the expert-adjudicated reference standard and agreement between radiologist-assessed 4X categorization and lung cancer diagnosis were evaluated. RESULTS: The 48 expert-adjudicated 4X nodules and 64 non-4X nodules were evenly distributed in each session. The proportion of category 4X decreased after training (56.4% ± 16.9% vs. 33.4% ± 8.0%; p < 0.001). Cohen's κ indicated poor agreement (0.39 ± 0.16) in session 1, but agreement improved in session 2 (0.47 ± 0.09; p = 0.03). The increase in agreement in session 2 was observed among inexperienced radiologists (p < 0.05), and experienced and inexperienced reviewers exhibited comparable agreement performance in session 2 (p > 0.05). All agreement measures between radiologist-assessed 4X categorization and lung cancer diagnosis increased in session 2 (p < 0.05). CONCLUSION: Radiologist training can improve reader agreement on 4X categorization, leading to enhanced diagnostic performance for lung cancer. KEY POINTS: • Agreement on 4X categorization between radiologists and an expert-adjudicated reference standard was initially poor, but improved significantly after training. • The mean proportion of 4X categorization by 19 radiologists decreased from 56.4% ± 16.9% in session 1 to 33.4% ± 8.0% in session 2. • All agreement measures between the 4X categorization and lung cancer diagnosis increased significantly in session 2, implying that appropriate training and guidance increased the diagnostic potential of category 4X.

Deep learning reconstruction for contrast-enhanced CT of the upper abdomen: similar image quality with lower radiation dose in direct comparison with iterative reconstruction.

OBJECTIVE: To evaluate the effect of a commercial deep learning algorithm on the image quality of chest CT, focusing on the upper abdomen. METHODS: One hundred consecutive patients who simultaneously underwent contrast-enhanced chest and abdominal CT were collected. The radiation dose was optimized for each scan (mean CTDIvol: chest CT, 3.19 ± 1.53 mGy; abdominal CT, 7.10 ± 1.88 mGy). Three image sets were collected: chest CT reconstructed with an adaptive statistical iterative reconstruction (ASiR-CHT; 50% blending), chest CT with a deep learning algorithm (DLIR-CHT), and abdominal CT with ASiR (ASiR-ABD; 40% blending). Afterwards, the images covering the upper abdomen were extracted, and image noise, the signal-to-noise ratio (SNR), and the contrast-to-noise ratio (CNR) were measured. For subjective evaluation, three radiologists independently assessed noise, spatial resolution, presence of artifacts, and overall image quality. Additionally, readers selected the most preferable reconstruction technique among three image sets for each case. RESULTS: The average measured noise for DLIR-CHT, ASiR-CHT, and ASiR-ABD was 8.01 ± 2.81, 14.8 ± 2.56, and 12.3 ± 2.28, respectively (p < .001). Deep learning-based image reconstruction (DLIR) also showed the best SNR and CNR (p < .001). However, in the subjective analysis, ASiR-ABD showed less subjective noise than DLIR (2.94 ± 0.23 vs. 2.87 ± 0.26; p < .001), while DLIR showed better spatial resolution (2.60 ± 0.34 vs. 2.44 ± 0.31; p = .02). ASiR-ABD showed a better overall image quality (p = .001), but two of the three readers preferred DLIR more frequently. CONCLUSION: With < 50% of the radiation dose, DLIR chest CT showed comparable image quality in the upper abdomen to that of dedicated abdominal CT and was preferred by most readers. KEY POINTS: • With < 50% radiation dose, a deep learning algorithm applied to contrast-enhanced chest CT exhibited better image noise and signal-to-noise ratio than standard abdominal CT with the ASiR technique. • Pooled readers mostly preferred deep learning algorithm-reconstructed contrast-enhanced chest CT reconstructed using a standard ASiR-reconstructed abdominal CT. • Reconstruction algorithm-induced distortion artifacts were more frequently observed on deep learning algorithm-reconstructed images, but diagnostic difficulty was reported in only 0.3% of cases.

Cochlear duct length and cochlear distance on preoperative CT: imaging markers for estimating insertion depth angle of cochlear implant electrode.

OBJECTIVES: Preoperative estimation of the insertion depth angle of cochlear implant (CI) electrodes is essential for surgical planning. The purpose of this study was to determine the cochlear size using preoperative CT and to investigate the correlation between cochlear size and insertion depth angle in morphologically normal cochlea. METHODS: Thirty-five children who underwent CI were included in this study. Cochlear duct length (CDL) and the diameter of the cochlear basal turn (distance A/B) on preoperative CT and the insertion depth angle of the CI electrode on postoperative radiographs were independently measured by two readers. Correlation between cochlear size and insertion depth angle was evaluated. Interobserver agreement was calculated using the intraclass correlation coefficient (ICC). RESULTS: The mean CDL, distance A, and distance B of 70 ears were 36.20 ± 1.57 mm, 8.67 ± 0.42 mm, and 5.73 ± 0.32 mm, respectively. The mean insertion depth angle was 431.45 ± 38.42°. Interobserver agreements of CDL, distance A/B, and insertion depth angle were fair to excellent (ICC 0.864, 0.862, 0.529, and 0.958, respectively). Distance A (r = - 0.7643) and distance B (r = - 0.7118) showed a negative correlation with insertion depth angle, respectively (p < 0.0001). However, the correlation between CDL and insertion depth angle was not statistically significant (r = - 0.2333, p > 0.05). CONCLUSIONS: The CDL and cochlear distance can be reliably obtained from preoperative CT. Distance A can be used as a predictive marker for estimating insertion depth angle during CI surgery.

Autoantibodies against Protein Phosphatase Magnesium-Dependent 1A as a Biomarker for Predicting Radiographic Progression in Ankylosing Spondylitis Treated with Anti-Tumor Necrosis Factor Agents.

BACKGROUND: Patients with ankylosing spondylitis (AS) have increased levels of protein phosphatase magnesium-dependent 1A (PPM1A) and autoantibodies. We evaluated the usefulness of serum anti-PPM1A antibodies as a biomarker for AS. METHODS: Serum samples from 58 AS patients were obtained from a multicenter registry prior to the initiation of anti-TNF agents. The serum levels of anti-PPM1A antibodies were measured using ELISA. Spinal radiographic progression was defined as an increase in the modified stoke ankylosing spondylitis spinal score (mSASSS) by ≥2 units or a newly developed syndesmophyte. The role of exogenous PPM1A on bone mineralization was evaluated using primary osteoprogenitors acquired from patients with AS and non-inflammatory controls. RESULTS: The baseline levels of anti-PPM1A antibodies and mSASSS were higher in the radiographic progression group than in the non-progression group. In logistic regression analysis, baseline mSASSS and serum anti-PPM1A antibodies were associated with a higher risk of progression. The level of anti-PPM1A antibodies for predicting progression had an AUC of 0.716 (cut-off value: 43.77 ng/mL). PPM1A stimulation increased matrix mineralization in AS-osteoprogenitors but not in controls. CONCLUSION: Along with mSASSS, the serum levels of anti-PPM1A antibodies might be useful as a predictor of radiographic progression after treatment with anti-TNF agents.

Association between Use of Hydrochlorothiazide and Nonmelanoma Skin Cancer: Common Data Model Cohort Study in Asian Population.

Although hydrochlorothiazide (HCTZ) has been suggested to increase skin cancer risk in white Westerners, there is scant evidence for the same in Asians. We analyzed the association between the use of hydrochlorothiazide and non-melanoma in the Asian population using the common data model. METHODS: A retrospective multicenter observational study was conducted using a distributed research network to analyze the effect of HCTZ on skin cancer from 2004 to 2018. We performed Cox regression to evaluate the effects by comparing the use of HCTZ with other antihypertensive drugs. All analyses were re-evaluated using matched data using the propensity score matching (PSM). Then, the overall effects were evaluated by combining results with the meta-analysis. RESULTS: Positive associations were observed in the use of HCTZ with high cumulative dose for non-melanoma skin cancer (NMSC) in univariate analysis prior to the use of PSM. Some negative associations were observed in the use of low and medium cumulative doses. CONCLUSION: Although many findings in our study were inconclusive, there was a non-significant association of a dose-response pattern with estimates increasing in cumulative dose of HCTZ. In particular, a trend with a non-significant positive association was observed with the high cumulative dose of HCTZ.

Hepatocellular Carcinoma: Texture Analysis of Preoperative Computed Tomography Images Can Provide Markers of Tumor Grade and Disease-Free Survival.

OBJECTIVE: To investigate the usefulness of computed tomography (CT) texture analysis (CTTA) in estimating histologic tumor grade and in predicting disease-free survival (DFS) after surgical resection in patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Eighty-one patients with a single HCC who had undergone quadriphasic liver CT followed by surgical resection were enrolled. Texture analysis of tumors on preoperative CT images was performed using commercially available software. The mean, mean of positive pixels (MPP), entropy, kurtosis, skewness, and standard deviation (SD) of the pixel distribution histogram were derived with and without filtration. The texture features were then compared between groups classified according to histologic grade. Kaplan-Meier and Cox proportional hazards analyses were performed to determine the relationship between texture features and DFS. RESULTS: SD and MPP quantified from fine to coarse textures on arterial-phase CT images showed significant positive associations with the histologic grade of HCC (p < 0.05). Kaplan-Meier analysis identified most CT texture features across the different filters from fine to coarse texture scales as significant univariate markers of DFS. Cox proportional hazards analysis identified skewness on arterial-phase images (fine texture scale, spatial scaling factor [SSF] 2.0, p < 0.001; medium texture scale, SSF 3.0, p < 0.001), tumor size (p = 0.001), microscopic vascular invasion (p = 0.034), rim arterial enhancement (p = 0.024), and peritumoral parenchymal enhancement (p = 0.010) as independent predictors of DFS. CONCLUSION: CTTA was demonstrated to provide texture features significantly correlated with higher tumor grade as well as predictive markers of DFS after surgical resection of HCCs in addition to other valuable imaging and clinico-pathologic parameters.

Infected cyst in patients with autosomal dominant polycystic kidney disease: Analysis of computed tomographic and ultrasonographic imaging features.

PURPOSE: To investigate the imaging features of cyst infection in autosomal dominant polycystic kidney disease (ADPKD) patients using computed tomography (CT) and ultrasonography (US). MATERIALS & METHODS: The institutional review board approved this retrospective study. Fifty-one episodes with proven cyst infection in forty-three ADPKD patients were included. Two experienced abdominal radiologists reviewed CT and US images and evaluated the following imaging features in consensus: cyst size, location, cyst shape, intracystic attenuation, intracystic echogenicity, intracystic heterogeneity, wall thickness, the presence of fluid-fluid level, septation, intracystic gas, pericystic fat infiltration, and pericystic hyperemia. Intracystic attenuation was measured for all infected cysts and two presumed normal cysts and compared using the Wilcoxon rank-sum test. RESULTS: On CT scans, the median size of infected cysts was 5.5 cm (range: 2.3-18.8 cm) and 46 of 51 (90.2%) infected cysts were located in the subcapsular region. Most (48 of 51, 94.1%) infected cysts showed lobulated, focal bulging or irregular shape. Discernible wall thickening (84.1%) was the most frequently found imaging feature of infected cysts followed by relatively higher intracystic attenuation compared to normal cysts (79.1%) and pericystic fat infiltration (52.9%). Fluid/fluid level was found in 3 of 51 (5.9%) infected cysts and intracystic gas was found in 3 of 51 (5.9%) infected cysts, respectively. For hepatic cysts, 11 of 14 (78.6%) infected cysts showed pericystic hyperemia. Intracystic attenuation was significantly higher in infected cysts (median; 19.0 HU) than in presumed normal cysts (median; 8.5 HU) (P<0.001), and exceeded 25 HU in 18 (35.3%) of 51 infected cysts. Among the 41 infected cysts for which US images were available, 35 (85.1%) showed heterogeneous echogenicity. CONCLUSION: Minute imaging features such as minimal wall thickening or relatively high attenuation compared to normal cysts would be helpful to detect infected cysts in ADPKD patients.

Enhanced cellular transfection by ternary non-viral gene vectors coupled with adeno-associated virus-derived peptides.

The establishment of efficient and safe gene delivery systems is crucial for biomedical applications. To address this objective, novel, ternary hybrid gene vectors are designed with viral capsid peptides in non-viral gene carriers. The viral peptide, TQVGQKT, is coupled with a membrane active peptide, LK15. Which acts as a linker to tag peptide with plasmid DNA. Additionally, polyethylenimine (PEI) is employed to condense the complexes further, thereby forming ternary DNA/TQVGQKT-LK15/PEI complexes. The ternary complexes result in rapid internalization leading to significantly enhanced cellular transfection. The new moiety, TQVGQKT, as well as enhanced cellular transfection, will certainly provide crucial insights for the design of novel non-viral gene carriers with efficient and safe properties.