Detecting sphenoid sinus fluid (SSF) is an additional finding in autopsies for diagnosing drowning. SSF can provide additional forensic evidence through laboratory tests such as diatom and electrolyte analyses. If drowning is suspected, accurately assessing the presence and volume of SSF during an autopsy is crucial. Utilizing postmortem computed tomography (PMCT) images could aid in accurately sampling SSF. Accurately segmenting the region of interest is essential for volume analysis using computed tomography images. However, manual segmentation techniques are labor-intensive and time-consuming, and their success depends on the experience of the observer. Therefore, this study aimed to develop a U-Net–based deep learning model for the automatic segmentation of SSF in drowning cases using PMCT images and to evaluate the performance of the model. We retrospectively reviewed 34 drowning cases in which both PMCT scans and forensic autopsies were performed at our institution. The U-Net architecture of deep learning was used for automatic segmentation. The proposed model achieved the Dice similarity coefficient (DSC) and Intersection over Union (IoU) of a maximum of 95.85% and 92.03%, a minimum of 0% and 0%, and an average of 77.15% and 67.18%, respectively. Although the average DSC and IoU did not show high similarity, this study showed that PMCT images can be used for automatic segmentation of SSF in drowning cases, which could improve the performance with sufficient dataset acquisition and further model training.

Abattoirs ; Agriculture ; Animals ; Drug Resistance, Multiple ; Farmers ; Korea ; Livestock ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; Multilocus Sequence Typing ; Phenotype ; Prevalence ; Red Meat ; Staphylococcus aureus ; Swine ; Tetracycline ; Zinc

The emergence of livestock-associated (LA)-methicillin-resistant Staphylococcus aureus (MRSA) in livestock animal has become a significant zoonotic concern. In the present study, we investigated nationwide prevalence of LA-MRSA across pork production chain including pig farms, slaughterhouses, and retail markets. A total of 40 MRSA strains were isolated during the investigation and the overall prevalence of MRSA was 3.4% (n = 37), 0.6% (n = 2), and 0.4% (n = 1) in pig farms, slaughterhouses, and retail markets, respectively. Multilocus sequence typing analyses revealed that the 2 most significant clonal lineages in pork production chain in Korea were ST398 (n = 25) and ST541 (n = 6). All of the 40 MRSA isolates were further characterized to investigate key genotypic and phenotypic correlates associated with the emergence and spread of clonal complex 398 (CC398; ST398, and ST541) LA-MRSA. Although the prevalence of swine-associated MRSA was still relatively low and mostly restricted to pig farms, multidrug-resistant CC398 LA-MRSA isolates with new spa types (t18102 and t18103) were identified as a major clonal lineage. The CC398 LA-MRSA strains tended to exhibit increased levels of multiple drug resistance (MDR) phenotype compared with non-CC398 MRSA strains. Of note, in comparison with non-CC398 MRSA isolates, CC398 LA-MRSA isolates exhibited significantly enhanced tetracycline (TET) and zinc resistance. These findings suggested that co-selection pressure associated with MDR phenotype, especially TET resistance, and zinc resistance may have played a significant role in the emergence and persistence of CC398 LA-MRSA in pig farms in Korea.

The emergence of livestock-associated (LA)-methicillin-resistant Staphylococcus aureus (MRSA) in livestock animal has become a significant zoonotic concern. In the present study, we investigated nationwide prevalence of LA-MRSA across pork production chain including pig farms, slaughterhouses, and retail markets. A total of 40 MRSA strains were isolated during the investigation and the overall prevalence of MRSA was 3.4% (n = 37), 0.6% (n = 2), and 0.4% (n = 1) in pig farms, slaughterhouses, and retail markets, respectively. Multilocus sequence typing analyses revealed that the 2 most significant clonal lineages in pork production chain in Korea were ST398 (n = 25) and ST541 (n = 6). All of the 40 MRSA isolates were further characterized to investigate key genotypic and phenotypic correlates associated with the emergence and spread of clonal complex 398 (CC398; ST398, and ST541) LA-MRSA. Although the prevalence of swine-associated MRSA was still relatively low and mostly restricted to pig farms, multidrug-resistant CC398 LA-MRSA isolates with new spa types (t18102 and t18103) were identified as a major clonal lineage. The CC398 LA-MRSA strains tended to exhibit increased levels of multiple drug resistance (MDR) phenotype compared with non-CC398 MRSA strains. Of note, in comparison with non-CC398 MRSA isolates, CC398 LA-MRSA isolates exhibited significantly enhanced tetracycline (TET) and zinc resistance. These findings suggested that co-selection pressure associated with MDR phenotype, especially TET resistance, and zinc resistance may have played a significant role in the emergence and persistence of CC398 LA-MRSA in pig farms in Korea.

Purpose: Despite advances in treatment, lung cancer remains the leading cause of cancer mortality. This study aimed to characterise genome-wide tumorigenesis events and to understand the hypothesis of the multistep carcinogenesis of lung adenocarcinoma (LUAD) Materials and Methods: We conducted multiregion whole-exome sequencing of LUAD with synchronous atypical adenomatous hyperplasia (AAH), adenocarcinoma in situ, or minimally invasive adenocarcinoma of 19 samples from three patients to characterize genome-wide tumorigenesis events and validate the hypothesis of the multistep carcinogenesis of LUAD. We identified potential pathogenic mutations preserved in preinvasive lesions and supplemented the finding by allelic variant level from RNA sequencing. Results: Overall, independent mutational profiles were observed per patient and between patients. Some shared mutations including epidermal growth factor receptor (EGFR , p.L858R) were present across synchronous lesions. Conclusion Here, we show that there are driver gene mutations in AAH, and they may exacerbate as a sequence in a histological continuum, supporting the Darwinian evolution model of cancer genome. The intertumoral and intratumoral heterogeneity of synchronous LUAD implies that multi-biomarker strategies might be necessary for appropriate treatment.

The emergence and prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-susceptible S. aureus (MSSA) in livestock animals have become a worldwide public health concern. While the prevalence and genetic profiles of MRSA strains in pigs and pork meat have been actively studied, livestock-associated MSSA strains have only been characterized in a few small-scale studies. In this investigation, we assessed the nationwide prevalence of MSSA in the Korean pig production chain, including pig farms, slaughterhouses, and retail markets. Among the 41 MSSA strains, the predominant clonal lineages were sequence type (ST) 398 (n = 15, 37%) and ST5 (n = 13, 32%). Although the overall prevalence of MSSA (2.58%) was low and mostly restricted to pig farms, ST398 MSSA strains showed higher level of multidrug resistance phenotype versus non-ST398 MSSA strains. In addition to the MDR phenotype, all of the ST398 MSSA strains exhibited resistance to tetracycline as they harbored the tet(K), tet(L), and/or tet(M) genes. However, ST398 MSSA strains did not exhibit increased resistance to zinc compared with the non-ST398 strains. This study is the first to provide evidence of ST398 MSSA emergence in livestock animals in Korea. Further studies are necessary to elucidate the potential of ST398 MSSA strains for human transmission. Our findings suggest that the MDR phenotype and high levels of tetracycline resistance may have played an important role in the emergence and prevalence of ST398 MSSA in pig farms in Korea.
Abattoirs ; Agriculture ; Animals ; Drug Resistance, Multiple ; Humans ; Korea ; Livestock ; Meat ; Methicillin-Resistant Staphylococcus aureus ; Phenotype ; Prevalence ; Public Health ; Red Meat ; Staphylococcus aureus ; Staphylococcus ; Swine ; Tetracycline ; Tetracycline Resistance ; Zinc

BACKGROUND/AIMS: Patients with chronic kidney disease (CKD) have a high risk of gastrointestinal tract bleeding because of platelet dysfunction attributable to uremia, a poor blood supply, and frequent use of anticoagulant agents. We describe the colonoscopic characteristics of lower gastrointestinal tract bleeding (LGIB) in patients with CKD. METHODS: A total of 230 hospitalized patients with CKD who underwent colonoscopy because of suspected LGIB between January 2003 and August 2016 were reviewed retrospectively. We categorized CKD into five stages according to the estimated glomerular filtration rate and compared the colonoscopic findings and clinical manifestations among these five subgroups. RESULTS: Of the 230 patients with CKD suspected of LGIB, 73 (31.7%, 103 cases) were colonoscopically confirmed to exhibit LGIB. Their mean age was 65.7 ± 12.8 years, and 52.1% were female (n = 38). The most common causes of LGIB were hemorrhoidal bleeding (32 cases, 43.8%), followed by bleeding of colorectal ulcers (21 cases, 28.8%), diverticular bleeding (12 cases, 16.4%), colitis-related bleeding (12 cases, 16.4%), and angiodysplastic bleeding (12 cases, 16.4%). As the CKD stage progressed, the incidence of LGIB increased (p = 0.043). On multivariate logistic regression analysis, LGIB was more common in CKD patients with hemorrhoids (odds ratio [OR]: 4.349, 95% confidence interval [CI]: 2.043–9.256, p < 0.001) or colorectal ulcers (OR: 20.001, 95% CI: 4.780–83.686, p ℃ 0.001) and in those on hemodialysis (OR: 6.863, 95% CI: 1.140–41.308, p = 0.035). CONCLUSIONS: In CKD patients, the risk of LGIB is significantly increased by hemorrhoids, colorectal ulcers, and a positive hemodialysis status.
Anticoagulants ; Blood Platelets ; Colonoscopy ; Female ; Gastrointestinal Tract ; Glomerular Filtration Rate ; Hemorrhage ; Hemorrhoids ; Humans ; Incidence ; Logistic Models ; Lower Gastrointestinal Tract ; Renal Dialysis ; Renal Insufficiency, Chronic ; Retrospective Studies ; Ulcer ; Uremia

PURPOSE: Programmed death-1 (PD-1)/PD-1 ligand (PD-L1) axis blockades have revolutionized the treatment of advanced non-small cell lung cancer (NSCLC). We assessed the effect of platinum-based chemotherapy on tumor PD-L1 expression and its clinical implications. MATERIALS AND METHODS: We used immunohistochemistry to retrospectively evaluate the percentage of tumor cells with membranous PD-L1 staining (tumor proportion score) in paired tumor specimens obtained before and after platinum-based neoadjuvant chemotherapy (NACT) in 86 patients with NSCLC. We analyzed the correlation between the change in PD-L1 tumor proportion score and clinicopathologic characteristics, response to NACT, and survival. RESULTS: The PD-L1 tumor proportion score increased in a significant proportion of patients with NSCLC after platinum-based NACT (Wilcoxon signed-rank test, p=0.002). That pattern was consistent across clinically defined subgroups except for patients with partial response to NACT. Tumors from 26 patients (30.2%) were PD-L1‒negative before NACT but PD-L1-positive after NACT, whereas the reverse pattern occurred in six patients (7%) (McNemar’s test, p < 0.001). Increase in PD-L1 tumor proportion score was significantly associated with lack of response to NACT (Fisher exact test, p=0.015). There was a tendency, albeit not statistically significant, for patients with an increase in PD-L1 tumor proportion score to have shorter survival. CONCLUSION: Tumor PD-L1 expression increased after platinum-based NACT in a significant proportion of patients with NSCLC. Increase in tumor PD-L1 expression may predict poor clinical outcome.
Carcinoma, Non-Small-Cell Lung ; Drug Therapy ; Humans ; Immunohistochemistry ; Neoadjuvant Therapy ; Platinum ; Prognosis ; Retrospective Studies

BACKGROUND/AIMS: The Crohn's and Colitis Knowledge (CCKNOW) score does not reflect updated knowledge relating to inflammatory bowel disease (IBD). The aim of this study was to develop, validate, and apply a novel tool to measure disease-related knowledge in IBD patients. METHODS: A questionnaire composed of 24 items regarding knowledge of IBD was developed: Inflammatory Bowel Disease Knowledge (IBD-KNOW). Discriminate ability of IBD-KNOW was validated in three occupational groups (14 doctors, 20 nurses, and 19 clerks). The CCKNOW and IBD-KNOW were administered to IBD patients. Factors affecting the level of IBD-related knowledge were analyzed. RESULTS: The median Inflammatory Bowel Disease Knowledge (IBD-KNOW) score was significantly different among the three groups for validation (22 doctors, 20 nurses, and five clerks; p < 0.001). The IBD-KNOW showed excellent internal consistency (Cronbach α = 0.952) and high correlation with CCKNOW (Spearman ρ = 0.827, p = 0.01). A total of 200 IBD patients (120 Crohn's disease, 80 ulcerative colitis) completed questionnaires. Multivariate analysis showed that a higher IBD-KNOW score than the median was associated with hospitalization history (odds ratio [OR], 2.625; p = 0.003), high education level (OR, 2.498; p = 0.012), and information acquired from patient organization (OR, 3.305, p = 0.035). CONCLUSIONS: The IBD-KNOW demonstrated excellent test characteristics. Hospitalization history, education level, and information acquired from patient organization play an important role in correct IBD-related knowledge.
Colitis ; Crohn Disease ; Education ; Hospitalization ; Humans ; Inflammatory Bowel Diseases* ; Multivariate Analysis ; Occupational Groups ; Ulcer

BACKGROUND/AIMS: Patients with chronic kidney disease (CKD) have a high risk of gastrointestinal tract bleeding because of platelet dysfunction attributable to uremia, a poor blood supply, and frequent use of anticoagulant agents. We describe the colonoscopic characteristics of lower gastrointestinal tract bleeding (LGIB) in patients with CKD. METHODS: A total of 230 hospitalized patients with CKD who underwent colonoscopy because of suspected LGIB between January 2003 and August 2016 were reviewed retrospectively. We categorized CKD into five stages according to the estimated glomerular filtration rate and compared the colonoscopic findings and clinical manifestations among these five subgroups. RESULTS: Of the 230 patients with CKD suspected of LGIB, 73 (31.7%, 103 cases) were colonoscopically confirmed to exhibit LGIB. Their mean age was 65.7 ± 12.8 years, and 52.1% were female (n = 38). The most common causes of LGIB were hemorrhoidal bleeding (32 cases, 43.8%), followed by bleeding of colorectal ulcers (21 cases, 28.8%), diverticular bleeding (12 cases, 16.4%), colitis-related bleeding (12 cases, 16.4%), and angiodysplastic bleeding (12 cases, 16.4%). As the CKD stage progressed, the incidence of LGIB increased (p = 0.043). On multivariate logistic regression analysis, LGIB was more common in CKD patients with hemorrhoids (odds ratio [OR]: 4.349, 95% confidence interval [CI]: 2.043–9.256, p < 0.001) or colorectal ulcers (OR: 20.001, 95% CI: 4.780–83.686, p ℃ 0.001) and in those on hemodialysis (OR: 6.863, 95% CI: 1.140–41.308, p = 0.035). CONCLUSIONS In CKD patients, the risk of LGIB is significantly increased by hemorrhoids, colorectal ulcers, and a positive hemodialysis status.