Brain endothelial cell-derived extracellular vesicles with a mitochondria-targeting photosensitizer effectively treat glioblastoma by hijacking the blood‒brain barrier

Glioblastoma (GBM) is the most aggressive malignant brain tumor and has a high mortality rate. Photodynamic therapy (PDT) has emerged as a promising approach for the treatment of malignant brain tumors. However, the use of PDT for the treatment of GBM has been limited by its low blood‒brain barrier (BBB) permeability and lack of cancer-targeting ability. Herein, brain endothelial cell-derived extracellular vesicles (bEVs) were used as a biocompatible nanoplatform to transport photosensitizers into brain tumors across the BBB. To enhance PDT efficacy, the photosensitizer chlorin e6 (Ce6) was linked to mitochondria-targeting triphenylphosphonium (TPP) and entrapped into bEVs. TPP-conjugated Ce6 (TPP-Ce6) selectively accumulated in the mitochondria, which rendered brain tumor cells more susceptible to reactive oxygen species-induced apoptosis under light irradiation. Moreover, the encapsulation of TPP-Ce6 into bEVs markedly improved the aqueous stability and cellular internalization of TPP-Ce6, leading to significantly enhanced PDT efficacy in U87MG GBM cells. An in vivo biodistribution study using orthotopic GBM-xenografted mice showed that bEVs containing TPP-Ce6 [bEV(TPP-Ce6)] substantially accumulated in brain tumors after BBB penetration via transferrin receptor-mediated transcytosis. As such, bEV(TPP-Ce6)-mediated PDT considerably inhibited the growth of GBM without causing adverse systemic toxicity, suggesting that mitochondria are an effective target for photodynamic GBM therapy.

Current status of ultrasonography in national cancer surveillance program for hepatocellular carcinoma in South Korea: a large-scale multicenter study

Background@#/Aim: Abdominal ultrasonography (USG) is recommended as a surveillance test for high-risk groups for hepatocellular carcinoma (HCC). This study aimed to analyze the current status of the national cancer surveillance program for HCC in South Korea and investigate the effects of patient-, physician-, and machine-related factors on HCC detection sensitivity. @*Methods@#This multicenter retrospective cohort study collected surveillance USG data from the high-risk group for HCC (liver cirrhosis or chronic hepatitis B or C >40 years of age) at eight South Korean tertiary hospitals in 2017. @*Results@#In 2017, 45 experienced hepatologists or radiologists performed 8,512 USG examinations. The physicians had a mean 15.0±8.3 years of experience; more hepatologists (61.4%) than radiologists (38.6%) participated. Each USG scan took a mean 12.2±3.4 minutes. The HCC detection rate by surveillance USG was 0.3% (n=23). Over 27 months of follow-up, an additional 135 patients (0.7%) developed new HCC. The patients were classified into three groups based on timing of HCC diagnosis since the 1st surveillance USG, and no significant intergroup difference in HCC characteristics was noted. HCC detection was significantly associated with patient-related factors, such as old age and advanced fibrosis, but not with physician- or machine-related factors. @*Conclusions@#This is the first study of the current status of USG as a surveillance method for HCC at tertiary hospitals in South Korea. It is necessary to develop quality indicators and quality assessment procedures for USG to improve the detection rate of HCC.

The development of hepatocellular carcinoma during long-term treatment for recurrent non-small cell lung cancer: a case report

Multiple primary malignancies (MPMs) are defined as the presence of two or more malignancies in different organs, without a subordinate relationship. Although rarely reported, hepatocellular carcinoma (HCC) occasionally presents with simultaneous or metachronous primary malignancies in other organs. In this report, we describe a patient with lung adenocarcinoma and lymph node and bone metastases, treated with five chemotherapeutic regimens for 24 months. Changing the chemotherapy regimen based on the suspicion of metastasis of a new liver mass did not lead to improvements. This prompted a liver biopsy and a revised diagnosis of HCC. Sixth-line treatment with the concurrent use of cisplatin-paclitaxel for lung cancer and sorafenib for HCC, stabilized the disease. The concurrent treatment was not tolerated and was discontinued owing to adverse events. Considering our findings, treatment with increased efficacy and lower toxicity for MPMs is warranted.

Mitochondria in reproduction / 대한생식의학회지

In reproduction, mitochondria produce bioenergy, help to synthesize biomolecules, and support the ovaries, oogenesis, and preimplantation embryos, thereby facilitating healthy live births. However, the regulatory mechanism of mitochondria in oocytes and embryos during oogenesis and embryo development has not been clearly elucidated. The functional activity of mitochondria is crucial for determining the quality of oocytes and embryos; therefore, the underlying mechanism must be better understood. In this review, we summarize the specific role of mitochondria in reproduction in oocytes and embryos. We also briefly discuss the recovery of mitochondrial function in gametes and zygotes. First, we introduce the general characteristics of mitochondria in cells, including their roles in adenosine triphosphate and reactive oxygen species production, calcium homeostasis, and programmed cell death. Second, we present the unique characteristics of mitochondria in female reproduction, covering the bottleneck theory, mitochondrial shape, and mitochondrial metabolic pathways during oogenesis and preimplantation embryo development. Mitochondrial dysfunction is associated with ovarian aging, a diminished ovarian reserve, a poor ovarian response, and several reproduction problems in gametes and zygotes, such as aneuploidy and genetic disorders. Finally, we briefly describe which factors are involved in mitochondrial dysfunction and how mitochondrial function can be recovered in reproduction. We hope to provide a new viewpoint regarding factors that can overcome mitochondrial dysfunction in the field of reproductive medicine.

A New Prognostic Index for Extranodal Natural Killer/T-Cell Lymphoma:Incorporation of Serum β-2 Microglobulin to PINK / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#Prognostic Index for Natural Killer Lymphoma (PINK) is the most widely accepted prognostic model for patients withextranodal natural killer/T-cell lymphoma (ENKTL) treated with non-anthracycline–based therapy. We aimed to evaluate the prognostic implications of serum β-2 microglobulin (β2M) in the context of PINK and proposed a new prognostic model. @*Materials and Methods@#A total of 138 patients who were newly diagnosed with ENKTL and treated with non-anthracycline-based chemotherapy were identified. The cut-off value of high serum β2M was calculated by maximal-chi square methods (4.1 mg/L). A new prognostic model incorporating serum β2M into PINK was proposed and validated in an independent validation cohort (n=88). @*Results@#The patients’ median age was 53.5 years (range, 19 to 80 years). Patients with high serum β2M levels had significantly worse overall survival (OS) and progression-free survival (PFS). In multivariate analysis, high serum β2M was an independent adverse prognostic factor for OS. A new PINK-B (Prognostic Index for Natural Killer Lymphoma-serum β-2 microglobulin) model stratifiedpatients into three groups with distinct OS and PFS in the training cohort (3-year OS, 84.1% [95% confidence interval, 75.1 to 94.2], 46.8% [36.1 to 60.8] and 17.6% [6.3 to 49.2] for the low-, intermediate, and high-risk groups, respectively; 3-year PFS, 70.6% [59.4 to 83.8], 35.9% [25.9 to 49.8], and 7.35% [1.1 to 46.7] for the low-, intermediate-, and high-risk groups, respectively). The PINK-B model was further validated in an independent cohort. @*Conclusion@#Serum β2M is an independent prognostic factor for ENKTL patients. The new serum β2M-based prognostic model may be useful for identifying ultra-high-risk patients, and it can easily be adopted into daily clinical practice.

Post-percutaneous core needle biopsy sputum cytology: diagnostic value and factors for positive prediction in diagnosing malignancy / 고신대학교의과대학학술지

Background@#This study evaluated the diagnostic yield and positive predictive factors of post-percutaneous core needle biopsy (PCNB) sputum cytology in diagnosing malignancy. @*Methods@#This retrospective study included patients who underwent PCNB at a single center from January 2014 to March 2022. Patient demographics, lung lesion characteristics on computed tomography, underlying lung disease, post-PCNB complications, histopathologic results of PCNB, post-PCNB sputum specimens, and final diagnoses were reviewed. The diagnostic yields and related factors were analyzed. @*Results@#Overall, 177 consecutive patients with sputum specimens obtained after PCNB for intrapulmonary lesions were enrolled. Among them, 152 patients had a final diagnosis of malignancy. Diagnostic sputum specimens with atypical or malignant cells were obtained in 12 patients. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of sputum cytology were 7.89%, 100%, 20.90%, 100%, and 15.15%, respectively. Lesion size, air-bronchogram, lesion multiplicity, and the cell type of squamous cell and adenocarcinoma differed significantly between the groups with diagnostic versus non-diagnostic sputum (p<0.05). The lesion size (odds ratio [OR], 1.035; 95% confidence interval [CI], 1.008–1.064; p=0.013), presence of air-bronchogram (OR, 23.485; 95% CI, 2.532–217.316; p=0.005), and squamous cell carcinoma (OR, 7.397; 95% CI, 1.773–30.865; p=0.006) were significantly associated with a diagnostic sputum specimen post-PCNB. @*Conclusions@#Although post-PCNB sputum cytology had low sensitivity in diagnosing lung cancer, it showed diagnostic results in some peripheral lung cancer patients who have squamous cell types, relatively large tumors, and air-bronchograms in the lesions.

Head and neck manifestations of fibrodysplasia ossificans progressiva: Clinical and imaging findings in 2 cases

Fibrodysplasia ossificans progressiva is a rare hereditary disorder characterized by progressive heterotopic ossifica-tion in muscle and connective tissue, with few reported cases affecting the head and neck region. Although plain radiographic findings and computed tomography features have been well documented, limited reports exist onmagnetic resonance findings. This report presents 2 cases of fibrodysplasia ossificans progressiva, one with limited mouth opening due to heterotopic ossification of the lateral pterygoid muscle and the other with restricted neck movement due to heterotopic ossification of the platysma muscle. Clinical findings of restricted mouth opening or limited neck movement, along with radiological findings of associated heterotopic ossification, should prompt consideration of fibrodysplasia ossificans progressiva in the differential diagnosis. Dentists should be particularly vigilant with patients diagnosed with fibrodysplasia ossificans progressiva to avoid exposure to diagnostic biopsy andinvasive dental procedures.

A case report of an unusual temporomandibular joint mass: Nodular fasciitis

Nodular fasciitis (NF) is a benign myofibroblastic proliferation that grows very rapidly, mimicking a sarcoma on imaging. It is treated by local excision, and recurrence has been reported in only a few cases, even when excised incompletely. The most prevalent diagnoses of temporomandibular joint (TMJ) masses include synovial chondromatosis, pigmented villonodular synovitis, and sarcomas. Cases of NF in the TMJ are extremely rare, and only 3 cases have been reported to date. Due to its destructive features and rarity, NF has often been misdiagnosed as a more aggressive lesion, which could expose patients to unnecessary and invasive treatment approaches beyond repair. This report presents a case of NF in the TMJ, focusing on various imaging features, along with a literature review aiming to determine the hallmark features of NF in the TMJ and highlight the diagnostic challenges.

Predictors of Post-chemoradiotherapy Pulmonary Complication in Locally Advanced Non–Small Cell Lung Cancer / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#We investigated the clinical effects and predictive factors of severe post-chemoradiotherapy pulmonary complications (PCPC) in locally advanced non–small cell lung cancer (LA-NSCLC). @*Materials and Methods@#Medical records of 317 patients who underwent definitive concurrent chemoradiation (CCRT) for LA-NSCLC were reviewed retrospectively. PCPC was defined as an event of admission or emergency department visit for acute or subacute pulmonary inflammatory complications, including pneumonitis and pneumonia, within 6 months after CCRT initiation. Patient characteristics, baseline lung function tests, radiation dosimetric parameters, and laboratory tests were analyzed to investigate their association with PCPC. Prognostic endpoints were disease progression rate (DPR) and overall survival (OS). @*Results@#PCPC was reported in 53 patients (16.7%). The OS of patients with PCPC was significantly worse (35.0% in 2 years) than that of patients without PCPC (67.0% in 2 years, p < 0.001). However, 2-year DPRs were 77.0% and 70.7% in patients with and without PCPC, respectively, which were not significantly different (p=0.087). In multivariate logistic regression, PCPC was independently associated with grade ≥ 1 hypoalbuminemia during CCRT (odds ratio [OR], 5.670; 95% confidence interval [CI], 2.487 to 13.40; p < 0.001), lower diffusing capacity of carbon monoxide (DLCO) (per mL/min/mmHg; OR, 0.855; 95% CI, 0.743 to 0.974; p=0.022), and higher lung V5 (per 10%; OR, 1.872; 95% CI, 1.336 to 2.699; p < 0.001). @*Conclusion@#PCPC might be a clinical endpoint to evaluate complications and predict the survival of patients subjected to CCRT for LA-NSCLC. Hypoalbuminaemia, DLCO, and lung V5 might predict PCPC in LA-NSCLC.

Understanding of Dense Breast and Perception of Breast Cancer Risk of Nurses with or without Dense Breast Notification

Purpose@#This study was conducted to identify nurses’ understanding of dense breast and their perception of breast cancer risk based on their status of dense breast notification. @*Methods@#Data were collected between September 13 and November 2, 2021, using self-report questionnaires from 220 female nurses in their 40s or 50s who are currently working at hospitals and have had mammogram experiences. @*Results@#Only 44.5% (n=98) of participants reported receiving dense breast notification; the remaining participants either did not receive the notification (n=106, 48.2%) or did not remember receiving it (n=16, 7.3%). Nurses’ status of dense breast notification was significantly associated with their understanding of dense breast, but not with their perception of breast cancer risk. @*Conclusion@#Future studies should focus on improving the notification process since nurses play a key role in educating clients about breast cancer prevention in relation to dense breast.

Orbital wall restoration with primary bone fragments in complex orbital fractures

Background@#Complex orbital fractures are impure orbital fractures because they involve the orbital walls and mid-facial bones. The author reported an orbital wall restoration technique in which the primary orbital wall fragments were restored to their prior position in complex orbital fractures in 2020. As a follow-up to a previous preliminary study, this study retrospectively reviewed the surgical results of complex orbital wall fractures over a 4-year period and compared the surgical outcomes by dividing them into groups with and without balloon restoration. @*Methods@#Data of 939 patients with facial bone fractures between August 2018 and August 2022 were reviewed. Of these, 154 had complex orbital fractures. Among them, 44 and 110 underwent reduction with and without the balloon technique respectively. Pre- and postoperative Naugle exophthalmometer (Good-Lite Co.) scales were evaluated. The orbital volume and orbital volume ratio were calculated from preoperative and 6 months postoperative computed tomography images. @*Results@#Among 154 patients with complex orbital fractures, 44 patients underwent restoration with the balloon technique, and 110 patients underwent restoration without it. The Naugle scale did not differ significantly between the two groups, but the orbital volume ratio significantly decreased by 3.32% and 2.39% in groups with and without the balloon technique and the difference in OVR was significantly greater in patients in the balloon restoration group compared with the control group. Postoperative balloon rupture occurred in six out of 44 cases (13.64%). None of the six patients with balloon rupture showed significant enophthalmos at 6 months of follow-up. @*Conclusion@#The balloon rupture rate was 13.64% (6/44 cases) with marginal screw fixation, blunt screws, and extra protection with a resorbable foam dressing. Furthermore, we restored the orbital wall with primary orbital fragments using balloon support in complex orbital wall fractures.

Highly water-soluble diacetyl chrysin ameliorates diabetes-associated renal fibrosis and retinal microvascular abnormality in db/db mice

BACKGROUND/OBJECTIVES@#Chronic or intermittent hyperglycemia is associated with the development of diabetic complications. Oxidative stress and inflammation can be altered by hyperglycemia in diverse tissues, including kidneys and eyes, and play a pivotal role in diabetic complications. Our previous studies showed that the water-insoluble 5,7-dihydroxyflvone chrysin effectively combats diabetic damages incurred in diabetic kidneys and retinas. The current study employed the newly-synthesized 5.7-di-O-acetylchrysin, having higher solubility than chrysin, to compare the effects on diabetes-associated renal fibrosis and abnormal retinal neovascularization.MATERIALS/METHODS: In the in vivo study, db/db mice as animal models of type 2 diabetes were orally administrated 10 mg/kg BW diacetylchrysin, daily for 10 weeks. @*RESULTS@#Unlike chrysin, oral administration of 10 mg/kg diacetylchrysin did not lower the blood glucose level and 24 h urine volume in db/db mice. Nevertheless, the urinary albumin excretion was markedly reduced. The administration of diacetylchrysin also diminished the deposition of collagen fibers in diabetic glomeruli and tubules by suppressing the induction of connective tissue growth factor and collagen IV in diabetic kidneys. Supplying diacetylchrysin enhanced the membrane type-1 matrix metalloproteinase (MMP) expression reduced in diabetic kidneys, while the tissue inhibitor of MMP-2 induction was attenuated in diacetylchrysin-challenged diabetic kidneys. In addition, supplementing diacetylchrysin to diabetic mice ameliorated renal injury due to glomerulosclerosis and tubular interstitial fibrosis. Furthermore, the reduced retinal inductions of Zonula occludens-1 and vascular endothelial cadherin in db/db mice were elevated in the retinal tissues of diacetylchrysintreated animals. Oral administration of diacetylchrysin curtailed the induction of vascular endothelial growth factor (VEGF) and VEGF receptor 2 in db/db mice, ultimately retarding diabetes-associated retinal neovascularization. Additionally, the retinal formation of acellular capillaries with leaky vessels was reduced in diacetylchrysin-treated db/db mice. @*CONCLUSION@#Diacetylchrysin may act as a potent pro-health agent for treating renal fibrosisassociated diabetic nephropathy and retinal neovascularization-associated diabetic retinopathy.

Aqueous extract of freeze-dried Protaetia brevitarsis larvae promotes osteogenesis by activating β-catenin signaling

Objective: To investigate the effect of an aqueous extract of Protaetia brevitarsis (AEPB) on osteogenesis using preosteoblast MC3T3-E1 cells and zebrafish larvae. Methods: Flow cytometric analysis was used to measure the cytotoxicy. Alkaline phosphatase activity was detetmined using p-nitrophenyl phosphate as a substrate. Calcium deposition was detected using alizarin red staining along with osteogenic marker expression in preosteoblast MC3T3E1 cells. In addition, vertebral formation in zebrafish larvae was detected using calcein staining and osteogenic gene expression. Results: AEPB highly promoted the expression of osteogenic markers including runt-related transcription factor 2, osterix, and alkaline phosphatase, along with elevated levels of mineralization in MC3T3-E1 cells. Moreover, AEPB accelerated vertebral formation in zebrafish larvae accompanied by upregulated expression of osteogenic genes. FH535, an inhibitor of Wnt/β-catenin, suppressed AEPB-induced osteogenic gene expression and vertebral formation, indicating that AEPB stimulates osteogenesis by activating the Wnt/β-catenin signaling pathway. Conclusions: AEPB stimulates osteoblast differentiation and bone formation by activating β-catenin. Therefore, AEPB is a promising material that induces osteogenesis, and is useful for the treatment of bone resorption diseases.

Clinical Efficacy of the Transradial Approach in Percutaneous Intervention for a Malfunctioning Arteriovenous Fistula

Purpose@#To evaluate the effectiveness of the transradial artery approach (TRA) for treating malfunctioning arteriovenous fistulas (AVFs) in patients on hemodialysis. @*Materials and Methods@#A retrospective analysis was conducted in this single-center study of TRA endovascular procedures in 73 patients (43 male and 30 female; mean age of 67.4 years (range, 42–92 years) with malfunctioning AVFs, between January 2008 and April 2019. Patients’ baseline and lesion characteristics, technical and clinical success, and complications were evaluated, and functional patency was analyzed using the Kaplan-Meier method. @*Results@#Radial artery approaches were successful in all patients. Angioplasty performed using the TRA achieved technical and clinical success rates of 98.6%(72/73) and 91.7%(67/73), respectively. The median primary patency time was 18.8 ± 15.9 months. The primary functional patency rates at 3, 6, and 12 months were 82.1%, 68.6%, and 63.9%, respectively. There were no major complications or adverse events, such as hand ischemia, related to the radial artery approach. @*Conclusion@#In selected cases, the TRA can be used complementary to the transvenous approach to treat malfunctioning AVFs.

Autoimmune Hepatitis Following Vaccination for SARS-CoV-2 in Korea:Coincidence or Autoimmunity?

Autoimmune hepatitis (AIH) is a chronic, autoimmune disease of the liver that occurs when the body’s immune system attacks liver cells, causing the liver to be inflamed. AIH is one of the manifestations of a coronavirus disease 2019 (COVID-19), as well as an adverse event occurring after vaccination against severe acute respiratory syndrome coronavirus 2 (SARSCoV-2). Few cases of AIH have been described after vaccination with two messenger RNA (mRNA)-based vaccines—BTN162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna)—against SARS-CoV-2. Herein, we report a case of AIH occurring after Pfizer-BioNTech COVID-19 vaccine. A 27-year-old female presented with jaundice and hepatomegaly, appearing 14 days after receiving the second dose of Pfizer-BioNTech vaccine. Her laboratory results showed abnormal liver function with high total immunoglobulin G level. She was diagnosed with AIH with histologic finding and successfully treated with oral prednisolone. We report an AIH case after COVID-19 vaccination in Korea.

Comparison of bolus administration effects of lidocaine on preventing tourniquet-induced hypertension in patients undergoing general anesthesia: a randomized controlled trial

Background@#This study assessed the effect of a single bolus administration of lidocaine on the prevention of tourniquet-induced hypertension (TIH) and compared the effect of lidocaine to that of ketamine in patients undergoing general anesthesia. @*Methods@#This randomized, controlled, double-blind study included 75 patients who underwent lower limb surgery using a tourniquet. The patients were administered lidocaine (1.5 mg/kg, n = 25), ketamine (0.2 mg/kg, n = 25) or placebo (n = 25). The study drugs were administered intravenously 10 min before tourniquet inflation. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were measured before tourniquet inflation, after tourniquet inflation for 60 min at 10 min intervals, and immediately after tourniquet deflation. The incidence of TIH, defined as an increase of 30% or more in SBP or DBP during tourniquet inflation, was also recorded. @*Results@#SBP, DBP, and HR increased significantly over time in the control group compared to those in the lidocaine and ketamine groups for 60 min after tourniquet inflation (P < 0.001, P < 0.001, and P = 0.007, respectively). The incidence of TIH was significantly lower in the lidocaine (n = 4, 16%) and ketamine (n = 3, 12%) group than in the control group (n = 14, 56%) (P = 0.001). @*Conclusion@#Single-bolus lidocaine effectively attenuated blood pressure increase due to tourniquet inflation, with an effect comparable to that of bolus ketamine.

Validation of Foot Pressure Variables during Walking according to Glycated Hemoglobin Levels / 임상당뇨병

The purpose of this study was to explore the variables of foot pressure according to glycated hemoglobin level during walking in diabetic patients with pes rectus. The subjects of this study were 39 people (78 feet) in their 40s and 60s, and they were divided into 11 pre-diabetic patients (22 feet) and 14 diabetic patients (28 feet) based on glycated hemoglobin; 14 patients without diabetes (28 feet) was used as a control. Foot pressure was measured using the EMED-LE Measurement system. The sole of the foot was divided into 12 parts, each of which was analyzed for pressure, force, contact area, and grounding time. For statistics, nonparametric Kruskal–Wallis and Wilcoxon signed rank test were used. Prediabetic and diabetic patients had lower hindfoot and second and third metatarsal foot pressure but higher first and third toe pressure compared to those without diabetes. In addition, the maximum and minimum force were high in all parts of the sole, and the contact time was long, signifying strong downward force for a long duration. Measurement of foot pressure by parts allowed detailed analysis of abnormal foot pressure and is valuable as basic data for diagnosis, prediction, and treatment of diabetic foot. Based on these data, maximum and minimum pressure better explain the problem of plantar pressure distribution rather than mean maximum pressure.

Dosimetric evaluation of magnetic resonance imaging-guided adaptive radiation therapy in pancreatic cancer by extent of re-contouring of organs-at-risk

Purpose@#The safety of online contouring and planning for adaptive radiotherapy is unknown. This study aimed to evaluate the dosimetric difference of the organ-at-risk (OAR) according to the extent of contouring in stereotactic magnetic resonance image-guided adaptive RT (SMART) for pancreatic cancer. @*Materials and Methods@#We reviewed the treatment plan data used for SMART in patients with pancreatic cancer. For the online contouring and planning, OARs within 2 cm from the planning target volume (PTV) in the craniocaudal direction were re-controlled daily at the attending physician's discretion. The entire OARs were re-contoured retrospectively for data analysis. We termed the two contouring methods the Rough OAR and the Full OAR, respectively. The proportion of dose constraint violation and other dosimetric parameters was analyzed. @*Results@#Nineteen patients with 94 fractions of SMART were included in the analysis. The dose constraint was violated in 10.6% and 43.6% of the fractions in Rough OAR and Full OAR methods, respectively (p = 0.075). Patients with a large tumor, a short distance from gross tumor volume (GTV) to OAR, and a tumor in the body or tail were associated with more occult dose constraint violations—large tumor (p = 0.027), short distance from GTV to OAR (p = 0.061), tumor in body or tail (p = 0.054). No dose constraint violation occurred outside 2 cm from the PTV. @*Conclusion@#More occult dose constraint violations can be found by the Full OAR method in patients with pancreatic cancer with some clinical factors in the online re-planning for SMART. Re-contouring all the OARs would be helpful to detect occult dose constraint violations in SMART planning. Since the dosimetric profile of SMART cannot be represented by a single fraction, patient selection for the Full OAR method should be weighted between the clinical usefulness and the time and workforce required.

Relationship of Job Stress to Turnover Intention in Hospital Nurses of Rural Areas: Job Embeddedness as a Mediator / 간호행정학회지

Purpose@#The purpose of this study was to identify the relationship between job stress and turnover intention and the mediating effect of job embeddedness on the relationship among hospital nurses in rural areas. @*Methods@#This is a descriptive study. A total of 277 registered nurses were enrolled in the study from three hospitals in rural areas of South Korea from April 29 to May 10, 2019. The participants completed self-reporting questionnaires, which measured job stress, turnover intention, and job embeddedness, and collected demographic information. The data were analyzed using IBM SPSS Statistics 25.0, for multiple regression, and a simple mediation model applying the Hayes PROCESS macro with a 95% bias-corrected bootstrap confidence interval (5,000 bootstrap resampling). @*Results@#Job stress had a direct effect (c’=0.35, p<.001) on turnover intention. It was also demonstrated that job embeddedness partially mediated the relationship between job stress and turnover intention among the hospital nurses (a ․ b=-0.40 × -0.58=0.23, 95% Boot C). @*Conclusion@#The job stress and turnover intention of nurses in rural areas are not higher than those in large cities. Nevertheless, hospital administrators need to provide a nursing workforce policy to increase job embeddedness and reduce nurses’ turnover intention.

Deep learning-based apical lesion segmentation from panoramic radiographs

Purpose@#Convolutional neural networks (CNNs) have rapidly emerged as one of the most promising artificial intelligence methods in the field of medical and dental research. CNNs can provide an effective diagnostic methodology allowing for the detection of early-staged diseases. Therefore, this study aimed to evaluate the performance of a deep CNN algorithm for apical lesion segmentation from panoramic radiographs. @*Materials and Methods@#A total of 1000 panoramic images showing apical lesions were separated into training (n=800, 80%), validation (n=100, 10%), and test (n=100, 10%) datasets. The performance of identifying apical lesions was evaluated by calculating the precision, recall, and F1-score. @*Results@#In the test group of 180 apical lesions, 147 lesions were segmented from panoramic radiographs with an intersection over union (IoU) threshold of 0.3. The F1-score values, as a measure of performance, were 0.828, 0.815, and 0.742, respectively, with IoU thresholds of 0.3, 0.4, and 0.5. @*Conclusion@#This study showed the potential utility of a deep learning-guided approach for the segmentation of apical lesions. The deep CNN algorithm using U-Net demonstrated considerably high performance in detecting apical lesions.