Background: and Purpose The National Brain Biobank of Korea (NBBK) is a brain bank consortium supported by the Korea Disease Control and Prevention Agency and the Korea National Institute of Health, and was launched in 2015 to support research into neurodegenerative disease dementia (NDD). This study aimed to introduce the NBBK and describes clinicopathological correlations based on analyses of data collected from the NBBK. Methods: Four hospital-based brain banks have been established in South Korea: Samsung Medical Center Brain Bank (SMCBB), Seoul National University Hospital Brain Bank (SNUHBB), Pusan National University Hospital Brain Bank (PNUHBB), and Myongji Hospital Brain Bank (MJHBB). Clinical and pathological data were collected from these brain banks using standardized protocols. The prevalence rates of clinical and pathological diagnoses were analyzed in order to characterize the clinicopathological correlations. Results: Between August 2016 and December 2023, 185 brain specimens were collected and pathologically evaluated (SNUHBB: 117; PNUHBB: 27; SMCBB: 34; MJHBB: 7). The age at consent was 70.8±12.6 years, and the age at autopsy was 71.7±12.4 years. The four-most-common clinical diagnoses were Alzheimer’s disease (AD) dementia (20.0%), idiopathic Parkinson’s disease (15.1%), unspecified dementia (11.9%), and cognitively unimpaired (CU) (11.4%).Most cases of unspecified dementia had a pathological diagnosis of central nervous system (CNS) vasculopathy (31.8%) or AD (31.8%). Remarkably, only 14.2% of CU cases had normal pathological findings. The three-most-common pathological diagnoses were AD (26.5%), CNS vasculopathy (14.1%), and Lewy body disease (13.5%). Conclusions These clinical and neuropathological findings provide a deeper understanding of the mechanisms underlying NDD in South Korea.

Background: We evaluated severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2)-specific humoral and cellular responses for up to 6 months after the 3rd dose of ancestral coronavirus disease 2019 (COVID-19) vaccination in people living with HIV (PLWH) and healthy controls (HCs) who were not infected with COVID-19. Methods: Anti-spike receptor-binding domain IgG (anti-RBD IgG) concentrations using chemiluminescence immunoassay and neutralizing antibodies using focus reduction neutralization test (FRNT) were assessed at 1 week after each dose of vaccination, and 3 and 6 months after the 3rd dose in 62 PLWH and 25 HCs. T-cell responses using intracellular cytokine stain were evaluated at 1 week before, and 1 week and 6 months after the 3rd dose. Results: At 1 week after the 3rd dose, adequate anti-RBD IgG (> 300 binding antibody unit /mL) was elicited in all PLWH except for one patient with 36 CD4 T-cell count/mm3 . The geometric mean titers of 50% FRNT against wild type (WT) and omicron BA.5 strains of SARS-CoV-2 in PLWH with CD4 T-cell count ≥ 500 cells/mm3(high CD4 recovery, HCDR) were comparable to HC, but they were significantly decreased in PLWH with CD4 T-cell count < 500/mm3 (low CD4 recovery, LCDR). After adjusting for age, gender, viral suppression, and number of preexisting comorbidities, CD4 T-cell counts < 500/mm3 significantly predicted a poor magnitude of neutralizing antibodies against WT, omicron BA.5, and XBB 1.5 strains among PLWH. Multivariable linear regression adjusting for age and gender revealed that LCDR was associated with reduced neutralizing activity (P = 0.017) and interferon-γ-producing T-cell responses (P = 0.049 for CD T-cell; P = 0.014 for CD8 T-cell) against WT, and strongly associated with more decreased cross-neutralization against omicron BA.5 strains (P < 0.001). Conclusion HCDR demonstrated robust humoral and cell-mediated immune responses after a booster dose of ancestral SARS-CoV-2 vaccine, whereas LCDR showed diminished immune responses against WT virus and more impaired cross-neutralization against omicron BA.5 strain.

von Hippel-Lindau (VHL) disease is a genetic condition predisposing individuals to the development of benign and malignant tumors across various organs. This review explores the intricate genetic underpinnings of VHL disease, its clinical manifestations, and the associated malignancy risks. The latest diagnostic criteria, surveillance guidelines, and advancements in therapeutic strategies, including the Food and Drug Administration-approved hypoxia-inducible factor-2α inhibitor, belzutifan, are focused on. Through a multidisciplinary approach, tailored surveillance programs aim to improve patient outcomes while balancing intervention risks. Emerging technologies such as wholebody magnetic resonance imaging and liquid biopsies hold promises for enhancing non-invasive surveillance. This review underscores the significance of ongoing research and interdisciplinary care in managing this complex syndrome.

Background: Epidermal growth factor receptor (EGFR) gene mutation testing is crucial for the administration of tyrosine kinase inhibitors to treat non–small cell lung cancer. In addition to traditional tissue-based tests, liquid biopsies using plasma are increasingly utilized, particularly for detecting T790M mutations. This study compared tissue- and plasma-based EGFR testing methods. Methods: A total of 248 patients were tested for EGFR mutations using tissue and plasma samples from 2018 to 2023 at Pusan National University Yangsan Hospital. Tissue tests were performed using PANAmutyper, and plasma tests were performed using the Cobas EGFR Mutation Test v2. Results: All 248 patients underwent tissue-based EGFR testing, and 245 (98.8%) showed positive results. Of the 408 plasma tests, 237 (58.1%) were positive. For the T790M mutation, tissue biopsies were performed 87 times in 69 patients, and 30 positive cases (38.6%) were detected. Plasma testing for the T790M mutation was conducted 333 times in 207 patients, yielding 62 positive results (18.6%). Of these, 57 (27.5%) were confirmed to have the mutation via plasma testing. Combined tissue and plasma tests for the T790M mutation were positive in nine patients (13.4%), while 17 (25.4%) were positive in tissue only and 12 (17.9%) in plasma only. This mutation was not detected in 28 patients (43.3%). Conclusions Although the tissue- and plasma-based tests showed a sensitivity of 37.3% and 32.8%, respectively, combined testing increased the detection rate to 56.7%. Thus, neither test demonstrated superiority, rather, they were complementary.

Purpose: This study evaluated the therapeutic efficacy of intravitreal methotrexate (MTX) injections in patients diagnosed with intraocular lymphoma via vitrectomy and immunocytochemical staining. Methods: In a retrospective analysis of medical records, we reviewed data from four patients (six eyes) diagnosed with intraocular lymphoma cytologically after undergoing vitrectomy at our hospital between December 2021 and December 2023. Each case was followed for a minimum of 6 months after treatment, with comparisons made between pre- and post-treatment observations Results: The mean age of the patients was 63.5 ± 9.8 years, with an average interval of 29.3 ± 32.0 months from initial symptom onset to intraocular lymphoma diagnosis. Diagnosis was confirmed through cytological and immunocytochemical analysis of vitreous specimens, identifying diffuse large B-cell lymphoma in four eyes and atypical lymphoid cells in two eyes. On average, 14.0 ± 1.7 intravitreal MTX injections were administered per eye. The mean best-corrected visual acuity improved from 1.18 ± 0.90 pre-treatment to 0.37 ± 0.70 post-treatment. Ophthalmic complications included toxic keratopathy in three eyes and retinal hemorrhage in one eye. Additionally, nasal cavity lymphoma was diagnosed in two patients. Conclusions Diagnostic vitrectomy combined with cytology and immunocytochemical staining is essential for the early diagnosis of intraocular lymphoma and differentiation from inflammatory diseases, such as uveitis. Intravitreal MTX injections can induce clinical remission in intraocular lymphoma cases.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection contribute to platelet activation and thrombus formation. Severe coronavirus disease 2019 (COVID-19) is characterized by an increased risk of thromboembolic events that can lead to adverse outcomes in patients with severe disease manifestations. We present the case of a 41-year-old man who died from a pulmonary embolism and review the connection between SARS-CoV-2 infection, increased platelet counts, and the resulting fatal thrombosis. Total knee replacement surgery was performed and the patient was able to ambulate for a few days postoperatively. The platelet count exceeded the upper limit between postoperative days six and nine, reaching 708,000/μL on day 20. SARS-CoV-2 was confirmed 14 days after surgery, and the patient died 23 days after surgery while hospitalized. Autopsy revealed a fatal pulmonary embolism and deep vein thrombosis. If blood clots are caused by increased platelet counts due to COVID-19, it is essential to understand this relationship and prepare for complications that may arise after infection. Several recent studies have shown a link between COVID-19 and coagulation. We propose several considerations for autopsies of unexpected fatal pulmonary embolism during the SARS-CoV-2 endemic period.

Background: Epidermal growth factor receptor (EGFR) gene mutation testing is crucial for the administration of tyrosine kinase inhibitors to treat non–small cell lung cancer. In addition to traditional tissue-based tests, liquid biopsies using plasma are increasingly utilized, particularly for detecting T790M mutations. This study compared tissue- and plasma-based EGFR testing methods. Methods: A total of 248 patients were tested for EGFR mutations using tissue and plasma samples from 2018 to 2023 at Pusan National University Yangsan Hospital. Tissue tests were performed using PANAmutyper, and plasma tests were performed using the Cobas EGFR Mutation Test v2. Results: All 248 patients underwent tissue-based EGFR testing, and 245 (98.8%) showed positive results. Of the 408 plasma tests, 237 (58.1%) were positive. For the T790M mutation, tissue biopsies were performed 87 times in 69 patients, and 30 positive cases (38.6%) were detected. Plasma testing for the T790M mutation was conducted 333 times in 207 patients, yielding 62 positive results (18.6%). Of these, 57 (27.5%) were confirmed to have the mutation via plasma testing. Combined tissue and plasma tests for the T790M mutation were positive in nine patients (13.4%), while 17 (25.4%) were positive in tissue only and 12 (17.9%) in plasma only. This mutation was not detected in 28 patients (43.3%). Conclusions Although the tissue- and plasma-based tests showed a sensitivity of 37.3% and 32.8%, respectively, combined testing increased the detection rate to 56.7%. Thus, neither test demonstrated superiority, rather, they were complementary.

Purpose: This study evaluated the therapeutic efficacy of intravitreal methotrexate (MTX) injections in patients diagnosed with intraocular lymphoma via vitrectomy and immunocytochemical staining. Methods: In a retrospective analysis of medical records, we reviewed data from four patients (six eyes) diagnosed with intraocular lymphoma cytologically after undergoing vitrectomy at our hospital between December 2021 and December 2023. Each case was followed for a minimum of 6 months after treatment, with comparisons made between pre- and post-treatment observations Results: The mean age of the patients was 63.5 ± 9.8 years, with an average interval of 29.3 ± 32.0 months from initial symptom onset to intraocular lymphoma diagnosis. Diagnosis was confirmed through cytological and immunocytochemical analysis of vitreous specimens, identifying diffuse large B-cell lymphoma in four eyes and atypical lymphoid cells in two eyes. On average, 14.0 ± 1.7 intravitreal MTX injections were administered per eye. The mean best-corrected visual acuity improved from 1.18 ± 0.90 pre-treatment to 0.37 ± 0.70 post-treatment. Ophthalmic complications included toxic keratopathy in three eyes and retinal hemorrhage in one eye. Additionally, nasal cavity lymphoma was diagnosed in two patients. Conclusions Diagnostic vitrectomy combined with cytology and immunocytochemical staining is essential for the early diagnosis of intraocular lymphoma and differentiation from inflammatory diseases, such as uveitis. Intravitreal MTX injections can induce clinical remission in intraocular lymphoma cases.