Synergistic Renoprotective Effects of Green Tea Extract and Gemigliptin against Tacrolimus-Induced Nephrotoxicity in Mice

SUMMARY: Although tacrolimus (TAC) significantly reduces allograft rejection incidence in solid-organ transplantation, its long-term use is associated with an increased risk of TAC-induced nephrotoxicity. In this study, we investigated the renoprotective effects of green tea extract (GTE) with or without the dipeptidyl peptidase 4 inhibitor, gemigliptin, by assessing serum creatinine levels, the amount of proteinuria, and histopathology in TAC-induced nephrotoxicity. TAC-induced nephrotoxicity was induced by intraperitoneal TAC injection, GTE was administered via subcutaneous injection, and gemigliptin was administered orally. Mice with TAC-induced nephrotoxicity exhibited a significant increase in both serum creatinine levels and 24-hour urine protein. However, when treated with GTE via subcutaneous injection, mice showed a decrease in serum creatinine levels and the amount of proteinuria. When GTE was combined with gemigliptin, further renoprotective effects were observed in biochemical assessments, consistent with the attenuation of TAC-induced nephrotoxicity in histopathology. The expression of p53 protein was lower in the mice treated with the combination of GTE and gemigliptin compared to mice with TAC-induced nephrotoxicity. Our results demonstrate that the combination of GTE and gemigliptin treatment reveals synergistic renoprotective effects by decreasing the expression of p53 protein. These findings suggest that the combination of GTE and gemigliptin could potentially be used as a prophylactic or therapeutic strategy for TAC-induced nephrotoxicity.

Aunque tacrolimus (TAC) reduce significativamente la incidencia de rechazo de aloinjertos en trasplantes de órganos sólidos, su uso a largo plazo se asocia con un mayor riesgo de nefrotoxicidad inducida por TAC. En este estudio, investigamos los efectos renoprotectores del extracto de té verde (GTE) con o sin el inhibidor de la dipeptidil peptidasa 4, gemigliptina, mediante la evaluación de los niveles de creatinina sérica, la cantidad de proteinuria y la histopatología en la nefrotoxicidad inducida por TAC. La nefrotoxicidad inducida por TAC se indujo mediante inyección intraperitoneal de TAC, el GTE se administró mediante inyección subcutánea y la gemigliptina se administró por vía oral. Los ratones con nefrotoxicidad inducida por TAC mostraron un aumento significativo tanto en los niveles de creatinina sérica como en la proteína en orina de 24 horas. Sin embargo, cuando se trataron con GTE mediante inyección subcutánea, los ratones mostraron una disminución en los niveles de creatinina sérica y en la cantidad de proteinuria. Cuando se combinó GTE con gemigliptina, se observaron efectos renoprotectores adicionales en las evaluaciones bioquímicas, lo que concuerda con la atenuación de la nefrotoxicidad inducida por TAC en histopatología. La expresión de la proteína p53 fue menor en los ratones tratados con la combinación de GTE y gemigliptina en comparación con los ratones con nefrotoxicidad inducida por TAC. Nuestros resultados demuestran que la combinación de tratamiento con GTE y gemigliptina revela efectos renoprotectores sinérgicos al disminuir la expresión de la proteína p53. Estos hallazgos sugieren que la combinación de GTE y gemigliptina podría usarse potencialmente como estrategia profiláctica o terapéutica para la nefrotoxicidad inducida por TAC.

A Randomized Phase II Study of Irinotecan Plus Cisplatin with or without Simvastatin in Ever-Smokers with Extended Disease Small Cell Lung Cancer / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#This study evaluated whether an addition of simvastatin to chemotherapy improves survival in ever-smokers with extensive disease (ED)–small cell lung cancer (SCLC). @*Materials and Methods@#This is an open-label randomized phase II study conducted in National Cancer Center (Goyang, Korea). Chemonaive patients with ED-SCLC, smoking history (≥ 100 cigarettes lifetime), and Eastern Cooperative Oncology Group performance status of ≤ 2 were eligible. Patients were randomized to receive irinotecan plus cisplatin alone or with simvastatin (40 mg once daily orally) for a maximum of six cycles. Primary endpoint was the the 1-year survival rate. @*Results@#Between September 16, 2011, and September 9, 2021, 125 patients were randomly assigned to the simvastatin (n=62) or control (n=63) groups. The median smoking pack year was 40 years. There was no significant difference in the 1-year survival rate between the simvastatin and control groups (53.2% vs. 58.7%, p=0.535). The median progression-free survival and overall survival between the simvastatin arm vs. the control groups were 6.3 months vs. 6.4 months (p=0.686), and 14.4 months vs. 15.2 months, respectively (p=0.749). The incidence of grade 3-4 adverse events was 62.9% in the simvastatin group and 61.9% in the control group. In the exploratory analysis of lipid profiles, patients with hypertriglyceridemia had significantly higher 1-year survival rates than those with normal triglyceride levels (80.0% vs. 52.7%, p=0.046). @*Conclusion@#Addition of simvastatin to chemotherapy provided no survival benefit in ever-smokers with ED-SCLC. Hypertriglyceridemia may be associated with better prognosis in these patient population.

Survival and Malignant Transformation of Pineal Parenchymal Tumors: A 30-Year Retrospective Analysis in a Single-Institution

Background@#This study aims to elucidate clinical features, therapeutic strategies, and prognosis of pineal parenchymal tumors (PPT) by analyzing a 30-year dataset of a single institution. @*Methods@#We reviewed data from 43 patients diagnosed with PPT at Seoul National UniversityHospital between 1990 and 2020. We performed survival analyses and assessed prognostic factors. @*Results@#The cohort included 10 patients with pineocytoma (PC), 13 with pineal parenchymaltumor of intermediate differentiation (PPTID), and 20 with pineoblastoma (PB). Most patients presented with hydrocephalus at diagnosis. Most patients underwent an endoscopic third ventriculostomy and biopsy, with some undergoing additional resection after diagnosis confirmation. Radiotherapy was administered with a high prevalence of gamma knife radiosurgery for PC and PPTID, and craniospinal irradiation for PB. Chemotherapy was essential in the treatment of grade 3 PPTID and PB. The 5-year progression-free survival rates for PC, grade 2 PPTID, grade 3 PPTID, and PB were 100%, 83.3%, 0%, and 40%, respectively, and the 5-year overall survival rates were 100%, 100%, 40%, and 55%, respectively. High-grade tumor histology was associated with lower survival rates. Significant prognostic factors varied among tumor types, with World Health Organization (WHO) grade and leptomeningeal seeding (LMS) for PPTID, and the extent of resection and LMS for PB. Three patients experienced malignant transformations. @*Conclusion@#This study underscores the prognostic significance of WHO grades in PPT. It is nec-essary to provide specific treatment according to tumor grade. Grade 3 PPTID showed a poor prognosis. Potential LMS and malignant transformations necessitate aggressive multimodal treatment and close-interval screening.

Licochalcone H Targets EGFR and AKT to Suppress the Growth of Oxaliplatin -Sensitive and -Resistant Colorectal Cancer Cells

Treatment of colorectal cancer (CRC) has always been challenged by the development of resistance. We investigated the antiproliferative activity of licochalcone H (LCH), a regioisomer of licochalcone C derived from the root of Glycyrrhiza inflata, in oxaliplatin (Ox)-sensitive and -resistant CRC cells. LCH significantly inhibited cell viability and colony growth in both Ox-sensitive and Ox-resistant CRC cells. We found that LCH decreased epidermal growth factor receptor (EGFR) and AKT kinase activities and related activating signaling proteins including pEGFR and pAKT. A computational docking model indicated that LCH may interact with EGFR, AKT1, and AKT2 at the ATP-binding sites. LCH induced ROS generation and increased the expression of the ER stress markers. LCH treatment of CRC cells induced depolarization of MMP. Multi-caspase activity was induced by LCH treatment and confirmed by Z-VAD-FMK treatment. LCH increased the number of sub-G1 cells and arrested the cell cycle at the G1 phase.Taken together LCH inhibits the growth of Ox-sensitive and Ox-resistant CRC cells by targeting EGFR and AKT, and inducing ROS generation and ER stress-mediated apoptosis. Therefore, LCH could be a potential therapeutic agent for improving not only Ox-sensitive but also Ox-resistant CRC treatment.

Licochalcone D Inhibits Skin Epidermal Cells Transformation through the Regulation of AKT Signaling Pathways

Cell transformation induced by epidermal growth factor (EGF) and 12-O-tetradecanoylphorbol-13-acetate (TPA) is a critical event in cancer initiation and progression, and understanding the underlying mechanisms is essential for the development of new therapeutic strategies. Licorice extract contains various bioactive compounds, which have been reported to have anticancer and anti-inflammatory effects. This study investigated the cancer preventive efficacy of licochalcone D (LicoD), a chalcone derivative in licorice extract, in EGF and TPA-induced transformed skin keratinocyte cells. LicoD effectively suppressed EGF-induced cell proliferation and anchorage-independent colony growth. EGF and TPA promoted the S phase of cell cycle, while LicoD treatment caused G1 phase arrest and down-regulated cyclin D1 and up-regulated p21 expression associated with the G1 phase. LicoD also induced apoptosis and increased apoptosis-related proteins such as cleaved-caspase-3, cleaved-caspase-7, and Bax (Bcl-2-associated X protein). We further investigated the effect of LicoD on the AKT signaling pathway involved in various cellular processes and found decreased p-AKT, p-GSK3β, and p-NFκB expression. Treatment with MK-2206, an AKT pharmacological inhibitor, suppressed EGF-induced cell proliferation and transformed colony growth. In conclusion, this study demonstrated the potential of LicoD as a preventive agent for skin carcinogenesis.

3-Deoxysappanchalcone Inhibits Cell Growth of Gefitinib-Resistant Lung Cancer Cells by Simultaneous Targeting of EGFR and MET Kinases

The mechanistic functions of 3-deoxysappanchalcone (3-DSC), a chalcone compound known to have many pharmacological effects on lung cancer, have not yet been elucidated. In this study, we identified the comprehensive anti-cancer mechanism of 3-DSC, which targets EGFR and MET kinase in drug-resistant lung cancer cells. 3-DSC directly targets both EGFR and MET, thereby inhibiting the growth of drug-resistant lung cancer cells. Mechanistically, 3-DSC induced cell cycle arrest by modulating cell cycle regulatory proteins, including cyclin B1, cdc2, and p27. In addition, concomitant EGFR downstream signaling proteins such as MET, AKT, and ERK were affected by 3-DSC and contributed to the inhibition of cancer cell growth. Furthermore, our results show that 3-DSC increased redox homeostasis disruption, ER stress, mitochondrial depolarization, and caspase activation in gefitinib-resistant lung cancer cells, thereby abrogating cancer cell growth. 3-DSC induced apoptotic cell death which is regulated by Mcl-1, Bax, Apaf-1, and PARP in gefitinib-resistant lung cancer cells. 3-DSC also initiated the activation of caspases, and the pan-caspase inhibitor, Z-VAD-FMK, abrogated 3-DSC induced-apoptosis in lung cancer cells. These data imply that 3-DSC mainly increased mitochondria-associated intrinsic apoptosis in lung cancer cells to reduce lung cancer cell growth. Overall, 3-DSC inhibited the growth of drug-resistant lung cancer cells by simultaneously targeting EGFR and MET, which exerted anti-cancer effects through cell cycle arrest, mitochondrial homeostasis collapse, and increased ROS generation, eventually triggering anticancer mechanisms. 3-DSC could potentially be used as an effective anti-cancer strategy to overcome EGFR and MET target drug-resistant lung cancer.

Novel anatomical guidelines for botulinum neurotoxin injection in the mentalis muscle:a review / 대한해부학회지

The mentalis muscle is a paired muscle originating from the alveolar bone of the mandible. This muscle is the main target muscle for botulinum neurotoxin (BoNT) injection therapy, which aims to treat cobblestone chin caused by mentalis hyperactivity. However, a lack of knowledge on the anatomy of the mentalis muscle and the properties of BoNT can lead to side effects, such as mouth closure insufficiency and smile asymmetry due to ptosis of the lower lip after BoNT injection procedures. Therefore, we have reviewed the anatomical properties associated with BoNT injection into the mentalis muscle.An up-to-date understanding of the localization of the BoNT injection point according to mandibular anatomy leads to better injection localization into the mentalis muscle. Optimal injection sites have been provided for the mentalis muscle and a proper injection technique has been described. We have suggested optimal injection sites based on the external anatomical landmarks of the mandible. The aim of these guidelines is to maximize the effects of BoNT therapy by minimizing the deleterious effects, which can be very useful in clinical settings.

Intramuscular neural distribution of the teres minor muscle using Sihler’s stain: application to botulinum neurotoxin injection / 대한해부학회지

The aim of this study was to elucidate the intramuscular arborization of the teres minor muslce for effective botulinum neurotoxin injection. Twelve specimens from 6 adult Korean cadavers (3 males and 3 females, age ranging from 66 to 78 years) were used in the study. The reference line between the 2/3 point of the axillary border of the scapula (0/5), where the muscle originates ant the insertion point of the greater tubercle of the humerus (5/5). The most intramuscular neural distribution was located on 1/5–3/5 of the muscle. The tendinous portion was observed in the 3/5–5/5. The result suggests the botulinum neurotoxin should be delivered in the 1/5–3/5 area of the teres minor muscle.

Novel anatomical proposal for botulinum neurotoxin injection targeting depressor anguli oris for treating drooping mouth corner / 대한해부학회지

The depressor anguli oris (DAO) muscle is a thin, superficial muscle located below the corner of the mouth. It is the target for botulinum neurotoxin (BoNT) injection therapy, aimed at treating drooping mouth corners. Hyperactivity of the DAO muscle can lead to a sad, tired, or angry appearance in some patients. However, it is difficult to inject BoNT into the DAO muscle because its medial border overlaps with the depressor labii inferioris and its lateral border is adjacent to the risorius, zygomaticus major, and platysma muscles. Moreover, a lack of knowledge of the anatomy of the DAO muscle and the properties of BoNT can lead to side effects, such as asymmetrical smiles. Anatomical-based injection sites were provided for the DAO muscle, and the proper injection technique was reviewed. We proposed optimal injection sites based on the external anatomical landmarks of the face. The aim of these guidelines is to standardize the procedure and maximize the effects of BoNT injections while minimizing adverse events, all by reducing the dose unit and injection points.

Report on the methacholine bronchial provocation test protocol: An updated statement of Korean Academy of Asthma, Allergy and Clinical Immunology

The Korean Academy of Asthma, Allergy, and Clinical Immunology task force report aims to provide new protocols for methacholine challenge test (MCT). Although new devices have different delivery system compared to old ones, previous protocols are still used, which cannot guarantee adequate diagnoses of asthma. Another important issue is the recent recommendation in European Respiratory Society (ERS) technical standard guideline to use a delivered methacholine dose that causes a 20% decrease in forced expiratory volume in 1 second (FEV1) (PD 20). Although the previous protocol based on the methacholine concentration causing a 20% decrease in FEV1 (PC 20) has been used globally, several studies have reported that PD 20 is more reliable and applicable for new protocols of MCT. Indeed, a tidal breathing inhalation protocol using a breath-actuated or continuous nebulizer is recommended. Herein, we recommend 3 protocols for the MCT using new devices and provide a brief summary of the change in strategy based on the updated ERS guideline.

Intramuscular Neural Distribution of Adductor Pollicis Muscle Spasticity in Cadaver Model Regarding Botulinum Neurotoxin Treatment

Purpose@#The adductor pollicis muscle is frequently targeted for botulinum neurotoxin injective treatment for spasticity. However, there are no injective guidelines for delivering injection to the muscle. @*Materials and Methods@#A method known as the modified Sihler’s method was used to stain the adductor pollicis muscle in 16 specimens to reveal intramuscular neural distribution of the muscle. @*Results@#The most intramuscular neural distribution was located on 1/5 to 3/5 of the muscle regarding midline of 3rd metacarpal bone (0) to the base of the 1st proximal phalanx (5/5). The nerve entry point was mostly located on 0 to 1/5 of the muscle. @*Conclusion@#The result suggests that botulinum neurotoxin should be delivered at the middle of second metacarpal bone via deep injection.

Intramuscular Neural Distribution of the Gastrocnemius for Botulinum Neurotoxin Injection:Application to Cosmetic Calf Shaping

Purpose@#Anatomical landmarks can provide vital information on the distribution of nerves in the gastrocnemius muscle. We aimed to provide an anatomical perspective on appropriate locations for botulinum neurotoxin (BoNT) injections in the medial and lateral parts of the gastrocnemius for calf shaping. @*Materials and Methods@#A modified Sihler’s method was applied to both the medial and lateral parts of the gastrocnemius muscles (16 specimens). Intramuscular neural distributions were revealed by dissecting along a transverse line crossing the fibular head and superior margin of the calcaneal tuberosity. @*Results@#The intramuscular neural distribution for the medial and lateral parts of the gastrocnemius had the greatest arborized patterns in the 7/10–8/10 section of the medial head and 7.5/10–8.5/10 section of the lateral part of the gastrocnemius. @*Conclusion@#We propose that BoNT injections should be directed to the 7/10–8/10 section of the medial head and the 7.5/10– 8.5/10 section of the lateral part of the gastrocnemius. Following our guidelines, clinicians can ensure satisfactory results with the use of minimal doses to limit adverse effects, such as gait disturbance, antibody production, and bruising, due to multiple injections. The results can also be altered and applied to electromyography.

Development of Hetero-Cell Type Spheroids Via Core–Shell Strategy for Enhanced Wound Healing Effect of Human AdiposeDerived Stem Cells

BACKGROUND@#Stem cell-based therapies have been developed to treat various types of wounds. Human adiposederived stem cells (hADSCs) are used to treat skin wounds owing to their outstanding angiogenic potential. Although recent studies have suggested that stem cell spheroids may help wound healing, their cell viability and retention rate in the wound area require improvement to enhance their therapeutic efficacy. @*METHODS@#We developed a core–shell structured spheroid with hADSCs in the core and human dermal fibroblasts (hDFs) in the outer part of the spheroid. The core–shell structure was formed by continuous centrifugation and spheroid incubation. After optimizing the method for inducing uniform-sized core–shell spheroids, cell viability, cell proliferation, migration, and therapeutic efficacy were evaluated and compared to those of conventional spheroids. @*RESULTS@#Cell proliferation, migration, and involucrin expression were evaluated in keratinocytes. Tubular assays in human umbilical vein endothelial cells were used to confirm the improved skin regeneration and angiogenic efficacy of core–shell spheroids. Core–shell spheroids exhibited exceptional cell viability under hypoxic cell culture conditions that mimicked the microenvironment of the wound area. @*CONCLUSION@#The improvement in retention rate, survival rate, and angiogenic growth factors secretion from core– shell spheroids may contribute to the increased therapeutic efficacy of stem cell treatment for skin wounds.

Various Three-Dimensional Culture Methods and Cell Types for Exosome Production

Cell-based therapies have been used as promising treatments for several untreatable diseases. However, cellbased therapies have side effects such as tumorigenesis and immune responses. To overcome these side effects, therapeutic effects of exosomes have been researched as replacements for cell-based therapies. In addition, exosomes reduced the risk that can be induced by cell-based therapies. Exosomes contain biomolecules such as proteins, lipids, and nucleic acids that play an essential role in cell–cell and cell–matrix interactions during biological processes. Since the introduction of exosomes, those have been proven perpetually as one of the most effective and therapeutic methods for incurable diseases. Much research has been conducted to enhance the properties of exosomes, including immune regulation, tissue repair, and regeneration. However, yield rate of exosomes is the critical obstacle that should be overcome for practical cell-free therapy. Three-dimensional (3D) culture methods are introduced as a breakthrough to get higher production yields of exosomes. For example, hanging drop and microwell were well known 3D culture methods and easy to use without invasiveness. However, these methods have limitation in mass production of exosomes. Therefore, a scaffold, spinner flask, and fiber bioreactor were introduced for mass production of exosomes isolated from various cell types. Furthermore, exosomes treatments derived from 3D cultured cells showed enhanced cell proliferation, angiogenesis, and immunosuppressive properties. This review provides therapeutic applications of exosomes using 3D culture methods.

Evaluation of Isometric Shoulder Muscle Contraction during Awakening after Arthroscopic Rotator Cuff Repair / 대한스포츠의학회지

Purpose@#Most rotator cuff repairs are performed under general anesthesia, and the shoulder muscles undergo exertion during the patient’s awakening. These may lead to subsequent retear. The purpose of this study is to evaluate the characteristics of shoulder muscle contraction during awakening from general anesthesia after rotator cuff repair. @*Methods@#Twenty patients underwent arthroscopic rotator cuff repair. Surface electromyography was used to investigate the amplitude of shoulder (upper trapezius [UT] and biceps brachii [BB]) and body (rectus femoris, RF) muscles during awakening in the operating room and resting in the postanesthesia care unit (PACU). @*Results@#The mean maximum voluntary isometric contraction (MVIC) of the UT, BB, and RF during awakening were 28.00%, 27.84%, and 35.65%, and the mean durations of activation were 3.98, 2.50, and 2.71 seconds. In the PACU, the mean MVIC of the UT, BB, and RF were 27.18%, 25.03%, and 27.20%, and the mean durations were 2.72, 0.26, and 0.67 seconds. No correlation between muscle contraction and postoperative pain was identified. @*Conclusion@#Less than 10% of the involuntary muscle contractions of the UT and BB measured in this study exceeded 20% of the MVIC and the contractions lasted less than 4 seconds. As the percentage of the MVIC of the rotator cuff is typically lower than that of the UT and BB, strong contractions of the rotator cuff muscle with detrimental effects occur at a low frequency and short duration. Therefore, retear due to muscle contraction during awakening is unlikely.

Comparative Study on the Clinical Characteristics of Transient Tachypnea of Newborns according to the Need for Invasive Mechanical Ventilation

Purpose@#Transient tachypnea of the newborn (TTN) is the most prevalent respiratory disease worldwide. Many neonates with TTN generally demonstrate spontaneous improvement. However, only few patients present with severe complications. This study aimed to investigate the differences in clinical features to identify neonates at risk for further complications. @*Methods@#Between January 2015 and December 2020, 267 neonates who developed dyspnea within 6 h of birth were delivered at a gestational age of at least 37 weeks. The experimental group (group E) included 44 neonates who required invasive mechanical ventilation, whereas the control group (group C) included 223 neonates who required only observation or non-invasive respiratory support. We analyzed the differences in clinical and perinatal factors between the two groups. @*Results@#Gestational age and pH on arterial blood gas analysis at admission were significantly lower in group E (p90 breaths/min), and pneumothorax, were more frequently observed in group E (p90 breaths/min), and need for respiratory assistance (fraction of inspired oxygen concentration ≥0.25) are predictive factors for increased risk of progression to a more severe disease course in neonates with TTN. Additional studies are needed to identify definitive factors that can differentiate TTN that improves spontaneously from TTN that requires intensive care.

Effect of Cultivation Stages of Hericium erinaceus on the Contents of Major Components and α-Glucosidase Inhibitory Activity

Hericium erinaceus, also known as lion’s mane mushroom, is an edible and medicinal mushroom that belongs to the family Hericiaceae. We previously reported hericene A as an anti-diabetic constituent of H. erinaceus and the effect of cultivation substrates on its content was investigated. As the continuation, the contents of five major compounds such as hericenes A-D, which exerted α-glucosidase inhibitory activity, together with ergosterol were investigated depending on cultivation stages. H. erinaceus was cultured for 25 days (5 stages) to induce fruiting bodies, and the contents of the compounds at each stage were quantified. All the five compounds were detected in fruiting body by HPLC analysis. Among the hericene derivatives in the mushroom, the content of hericene A was the highest, followed by hericene C and the content of hericenes B and D was relative low. All four hericene derivatives present in the highest content at stage 4 whereas the content of ergosterol was highest at stage 5. The highest α-glucosidase inhibitory activity of H. erinaceus was measured at stage 4, which correlates with the contents of hericene derivatives. Conclusively, H. erinaceus with better efficacy and high content of active constituents can be secured by the optimization of cultivation conditions.

Disseminated Staphylococcus aureus infection and acute bacterial pericarditis: a case report / 고신대학교의과대학학술지

We experienced a case of disseminated Staphylococcus aureus infection with bacterial pericarditis that progressed to septic shock and multiorgan failure despite pericardiocentesis and surgical removal of the original abscess with intensive antibiotic therapy. We report this case because of the patient’s very rare and remarkable echocardiographic findings and highly turbid pericardial effusion.

Hemorrhagic disease caused by bovine viral diarrhea virus-2a in Korean Indigenous Cattle: case reports

Bovine viral diarrhea virus (BVDV), which is prevalent worldwide, is one of the most important viral pathogens and causes substantial economic loss to the livestock industry. Despite its importance, BVDV is largely unnoticed in the Republic of Korea (ROK). In this study, we report the case of a steer with BVDV that died suddenly due to severe enteritis. Two 1-year-old Korean indigenous cattle in the same herd presented severe hemorrhagic diarrhea. Case 1 had severe dehydration and died after 3 days, whereas case 2 had anorexia, depression, and severe diarrhea with mucus and blood. Only case 2 was necropsied, and BVDV2a was detected in the tissues of its alimentary tract. Gross lesions, including erosion, ulceration, and extensive hemorrhage, were observed in the digestive tract mucosa. Immunohistochemistry revealed marked positive staining for BVDV2a antigen in the large intestine. This report describes the first case of hemorrhagic disease caused by acute BVDV2a infection, which is characterized by high mortality in Korean indigenous cattle. This study will help establish vaccination and control strategies for BVDV in the ROK.

Validation of CT-Based Risk Stratification System for Lymph Node Metastasis in Patients With Thyroid Cancer

Objective@#To evaluate the computed tomography (CT) features for diagnosing metastatic cervical lymph nodes (LNs) in patients with differentiated thyroid cancer (DTC) and validate the CT-based risk stratification system suggested by the Korean Thyroid Imaging Reporting and Data System (K-TIRADS) guidelines. @*Materials and Methods@#A total of 463 LNs from 399 patients with DTC who underwent preoperative CT staging and ultrasound-guided fine-needle aspiration were included. The following CT features for each LN were evaluated: absence of hilum, cystic changes, calcification, strong enhancement, and heterogeneous enhancement. Multivariable logistic regression analysis was performed to identify independent CT features associated with metastatic LNs, and their diagnostic performances were evaluated. LNs were classified into probably benign, indeterminate, and suspicious categories according to the K-TIRADS and the modified LN classification proposed in our study. The diagnostic performance of both classification systems was compared using the exact McNemar and Kosinski tests. @*Results@#The absence of hilum (odds ratio [OR], 4.859; 95% confidence interval [CI], 1.593–14.823; P = 0.005), strong enhancement (OR, 28.755; 95% CI, 12.719–65.007; P < 0.001), and cystic changes (OR, 46.157; 95% CI, 5.07–420.234; P = 0.001) were independently associated with metastatic LNs. All LNs showing calcification were diagnosed as metastases. Heterogeneous enhancement did not show a significant independent association with metastatic LNs. Strong enhancement, calcification, and cystic changes showed moderate to high specificity (70.1%–100%) and positive predictive value (PPV) (91.8%–100%). The absence of the hilum showed high sensitivity (97.8%) but low specificity (34.0%). The modified LN classification, which excluded heterogeneous enhancement from the K-TIRADS, demonstrated higher specificity (70.1% vs. 62.9%, P = 0.016) and PPV (92.5% vs. 90.9%, P = 0.011) than the K-TIRADS. @*Conclusion@#Excluding heterogeneous enhancement as a suspicious feature resulted in a higher specificity and PPV for diagnosing metastatic LNs than the K-TIRADS. Our research results may provide a basis for revising the LN classification in future guidelines.