Artificial intelligence (AI) has rapidly transformed various aspects of life, and the launch of the chatbot “ChatGPT” by OpenAI in November 2022 has garnered significant attention and user appreciation. ChatGPT utilizes natural language processing based on a ”generative pre-trained transfer” (GPT) model, specifically the transformer architecture, to generate human-like responses to a wide range of questions and topics. Equipped with approximately 57 billion words and 175 billion parameters from online data, ChatGPT has potential applications in medicine and orthopedics. One of its key strengths is its personalized, easy-to-understand, and adaptive response, which allows it to learn continuously through user interaction. This article discusses how AI, especially ChatGPT, presents numerous opportunities in orthopedics, ranging from preoperative planning and surgical techniques to patient education and medical support. Although ChatGPT’s user-friendly responses and adaptive capabilities are laudable, its limitations, including biased responses and ethical concerns, necessitate its cautious and responsible use. Surgeons and healthcare providers should leverage the strengths of the ChatGPT while recognizing its current limitations and verifying critical information through independent research and expert opinions. As AI technology continues to evolve, ChatGPT may become a valuable tool in orthopedic education and patient care, leading to improved outcomes and efficiency in healthcare delivery. The integration of AI into orthopedics offers substantial benefits but requires careful consideration and continuous improvement.

Viral load and the duration of viral shedding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are important determinants of the transmission of coronavirus disease 2019.In this study, we examined the effects of viral doses on the lung and spleen of K18-hACE2 transgenic mice by temporal histological and transcriptional analyses. Approximately, 1×105 plaque-forming units (PFU) of SARS-CoV-2 induced strong host responses in the lungs from 2 days post inoculation (dpi) which did not recover until the mice died, whereas responses to the virus were obvious at 5 days, recovering to the basal state by 14 dpi at 1×102 PFU. Further, flow cytometry showed that number of CD8+ T cells continuously increased in 1×102 PFU-virusinfected lungs from 2 dpi, but not in 1×105 PFU-virus-infected lungs. In spleens, responses to the virus were prominent from 2 dpi, and number of B cells was significantly decreased at 1×105PFU; however, 1×102 PFU of virus induced very weak responses from 2 dpi which recovered by 10 dpi. Although the defense responses returned to normal and the mice survived, lung histology showed evidence of fibrosis, suggesting sequelae of SARS-CoV-2 infection. Our findings indicate that specific effectors of the immune response in the lung and spleen were either increased or depleted in response to doses of SARS-CoV-2. This study demonstrated that the response of local and systemic immune effectors to a viral infection varies with viral dose, which either exacerbates the severity of the infection or accelerates its elimination.

Background/Aims: Epstein-Barr virus (EBV) and Helicobacter pylori (HP) coinfection may synergistically induce severe inflammatory responses in the stomach tissue, increasing the risk of developing gastric cancer. We aimed to analyze the effect of EBV and HP coinfection on the clinicopathologic features and prognosis of gastric cancer, as well as to evaluate the role of EBV infection in non-gastric carcinoma with lymphoid stroma (non-GCLS). Methods: Overall, 956 patients who underwent surgery for gastric cancer between September 2014 and August 2015 were eligible and divided into groups, according to GCLS morphology, EBV infection, and HP infection. Clinicopathologic characteristics and oncologic outcomes were analyzed retrospectively. Results: EBV and HP coinfection was significantly associated with male sex, proximal location, GCLS morphology, and equivocal p53 expression (p<0.001). Multivariate analysis revealed that EBV infection alone (hazard ratio [HR], 0.362; 95% CI, 0.131 to 0.996; p=0.049) and lower third location (HR, 0.624; 95% CI, 0.413 to 0.943; p=0.025) were inversely correlated with overall survival. During median follow-up period of 72 months, overall survival rate was not significantly different between the EBV and HP coinfection group and others (97.6% vs 86.8%, log-rank p=0.144). In non-GCLS patients (n=920), overall survival rate was not significantly different between the EBV infection group and others (96.9% vs 86.4%, log-rank p=0.126). Conclusions EBV and HP coinfection is not an independent prognostic factor for gastric cancer. EBV infection status, regardless of HP infection, affects the clinicopathologic features of all types of gastric cancer. However, it does not lead to a significant difference in overall survival of nonGCLS patients.

Background/Aims: AT-rich interactive domain 1A (ARID1A) is frequently mutated in gastric cancer (GC), especially Epstein-Barr virus (EBV)-associated and microsatellite instability high GC.The loss of ARID1A expression has been reported as a poor prognostic marker in GC. However, the relationships between ARID1A alteration and EBV-associated and microsatellite instability high GC, which are known to have a favorable prognosis, has hampered proper evaluation of the prognostic significance of ARID1A expression in GC. We aimed to analyze the true prognostic significance of ARID1A expression by correcting confounding variables. Methods: We evaluated the ARID1A expression in a large series (n=1,032) of advanced GC and analyzed the relationships between expression pattern and variable parameters, including clinicopathologic factors, key molecular features such as EBV-positivity, mismatch repair protein deficiency, and expression of p53 and several receptor tyrosine kinases including human epidermal growth factor receptor 2, epidermal growth factor receptor, and mesenchymal-epithelial transition factor. Survival analysis of the molecular subtypes was done according to the ARID1A expression patterns. Results: Loss of ARID1A expression was found in 52.5% (53/101) of mutL homolog 1 (MLH1)-deficient and 35.8% (24/67) of EBV-positive GCs, compared with only 9.6% (82/864) of the MLH1-proficient and EBV-negative group (p<0.001). The loss of ARID1A expression was associated only with MLH1 deficiency and EBV positivity. On survival analysis, the loss of ARID1A expression was associated with worse prognosis only in MLH1-proficient and EBV-negative GC. Multivariate analysis revealed that both loss of ARID1A and decreased ARID1A expression were independent worse prognostic factors in patients with advanced GC. Conclusions Only in MLH1-proficient and EBV-negative GC, the loss of ARID1A expression is related to poorer prognosis.

OBJECTIVES: We estimated the population prevalence of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), including unreported infections, through a Korea Seroprevalence Study of Monitoring of SARS-CoV-2 Antibody Retention and Transmission (K-SEROSMART) in 258 communities throughout Korea. METHODS: In August 2022, a survey was conducted among 10,000 household members aged 5 years and older, in households selected through two stage probability random sampling. During face-to-face household interviews, participants self-reported their health status, COVID-19 diagnosis and vaccination history, and general characteristics. Subsequently, participants visited a community health center or medical clinic for blood sampling. Blood samples were analyzed for the presence of antibodies to spike proteins (anti-S) and antibodies to nucleocapsid proteins (anti-N) SARS-CoV-2 proteins using an electrochemiluminescence immunoassay. To estimate the population prevalence, the PROC SURVEYMEANS statistical procedure was employed, with weighting to reflect demographic data from July 2022. RESULTS: In total, 9,945 individuals from 5,041 households were surveyed across 258 communities, representing all basic local governments in Korea. The overall population-adjusted prevalence rates of anti-S and anti-N were 97.6% and 57.1%, respectively. Since the Korea Disease Control and Prevention Agency has reported a cumulative incidence of confirmed cases of 37.8% through July 31, 2022, the proportion of unreported infections among all COVID-19 infection was suggested to be 33.9%. CONCLUSIONS The K-SEROSMART represents the first nationwide, community-based seroepidemiologic survey of COVID-19, confirming that most individuals possess antibodies to SARS-CoV-2 and that a significant number of unreported cases existed. Furthermore, this study lays the foundation for a surveillance system to continuously monitor transmission at the community level and the response to COVID-19.

Background: As the number of large-scale studies involving multiple organizations producing data has steadily increased, an integrated system for a common interoperable format is needed. In response to the coronavirus disease 2019 (COVID-19) pandemic, a number of global efforts are underway to develop vaccines and therapeutics. We are therefore observing an explosion in the proliferation of COVID-19 data, and interoperability is highly requested in multiple institutions participating simultaneously in COVID-19 pandemic research. Results: In this study, a laboratory information management system (LIMS) approach has been adopted to systemically manage various COVID-19 non-clinical trial data, including mortality, clinical signs, body weight, body temperature, organ weights, viral titer (viral replication and viral RNA), and multiorgan histopathology, from multiple institutions based on a web interface. The main aim of the implemented system is to integrate, standardize, and organize data collected from laboratories in multiple institutes for COVID-19 non-clinical efficacy testings. Six animal biosafety level 3 institutions proved the feasibility of our system. Substantial benefits were shown by maximizing collaborative high-quality non-clinical research. Conclusions This LIMS platform can be used for future outbreaks, leading to accelerated medical product development through the systematic management of extensive data from non-clinical animal studies.

Background: This study aimed to present the surgical facilitation of neurovascular bundle (NVB) sparing using the toggling technique (30° lens down/up switching) and to evaluate erectile dysfunction (ED) recovery after robot-assisted radical prostatectomy (RARP). Methods: We assessed 144 patients (group with toggling, n = 72; group without toggling, n = 72) who underwent RARP with bilateral NVB sparing using propensity score matching.Inclusion criteria were ≥ 1 year follow-up and preoperative potency as per the Sexual Health Inventory for Men (SHIM) questionnaire (≥ 17 points). Recovery of ED after RARP was defined as return to baseline sexual function or self-assessment regarding successful intercourse. The subjective surgeon’s nerve sparing (SNS) score and tunneling success rates were used to evaluate surgical facilitation. The recovery rate of ED between the groups was analyzed using Kaplan-Meier analysis. Results: A better ED recovery trend was confirmed according to the SNS score (R 2 = 0.142, P = 0.004). In the analysis of NVB sparing ease, the toggling group showed higher SNS scores (on right/left side: P = 0.011 and < 0.001, respectively) and overall tunneling success rates (87% vs. 74%, P = 0.001) than the group without toggling. Overall, ED recovery rates were 82% (59/72) and 75% (54/72) in the groups with and without toggling, respectively, at the 1-year follow-up (P = 0.047), and the toggling group showed a faster ED recovery rate at 3 months (47% vs. 35%, P = 0.013). In a specific analysis of the potent cohort (< 60 years, bilateral full NVB spared, SHIM score ≥ 22), the ED recovery rate reached 87% (14/16) in the toggling group. Conclusion The retrograde early release with the toggling technique improves the facilitation of NVB sparing, leading to improved ED recovery.

Background: and Purpose Ischemic stroke recurs despite the use of antiplatelet agents. Various mechanisms are involved in recurrence due to intracranial atherosclerosis (ICAS) and extracranial atherosclerosis (ECAS). High-on-aspirin platelet reactivity (HAPR) may differ between recurrent stroke due to ICAS and ECAS. Methods: Patients with recurrent ischemic stroke as a result of large-artery atherosclerosis despite taking aspirin were enrolled consecutively. Ischemic stroke was classified as stroke due to ICAS or ECAS according to the location of the culprit stenosis. An aspirin reaction units (ARU) value of >550 IU was defined as HAPR. HAPR and its associated factors were compared between the two groups and also considering the mechanism of stroke. Results: Among the 190 patients with recurrent stroke (111 with ICAS and 79 with ECAS), 36 (18.3%) showed HAPR. The ARU value was higher in the ECAS than the ICAS group (492± 83 vs. 465±78, mean±standard deviation; p=0.028), as was the proportion of patients with HAPR (27.8% vs. 12.6%, p=0.008). Being male and having stroke due to ECAS (reference = stroke due to ICAS: odds ratio=5.760; 95% confidence interval=2.154–15.403; p<0.001) was independently associated with HAPR. The ARU value differed according to the stroke mechanism, and was highest in those with artery-to-artery embolism. Artery-to-artery embolism was independently associated with HAPR in both the ICAS and ECAS groups. Conclusions Recurrent stroke due to ECAS was more strongly associated with HAPR and insufficient antiplatelet inhibition than was that due to ICAS. Artery-to-artery embolism was associated with HAPR in recurrent ischemic stroke as a result of ICAS or ECAS.

Background/Aims: Although localized lymphoid hyperplasia (LLH) of the rectum is occasionally observed, its clinical implications are unclear. This study aimed to investigate the clinical course and significance of LLH of the rectum. Methods: We identified 65 patients diagnosed with LLH of the rectum using a histopathologic examination and who received follow-up endoscopies between January 2009 and June 2015. Patients with a history of inflammatory bowel disease, lymphoma, familial adenomatous polyposis, or uncontrolled malignancy and patients who underwent scar biopsy after endoscopic resection or surgery were excluded. Endoscopic findings and clinical courses were analyzed. Results: During the median follow-up of 31 months (interquartile range, 19 to 40 months), 81.5% (53/65) of LLHs of the rectum were resolved. Clinically significant diseases, including ulcerative colitis (UC, n=5) and mucosa-associated lymphoid tissue (MALT) lymphoma (n=1), were diagnosed in 9.2% of patients (6/65). The other six patients showed no significant changes in the lesion (n=3) or a waxing and waning appearance (n=3). According to endoscopic findings, all of the 47 polypoid types showed resolution or waxing and waning patterns. Five of the 11 nodular types (45.5%) developed into UC. One of the seven submucosal tumor (SMT)-like types (14.3%) developed into MALT lymphoma. Conclusions LLH of the rectum with persistent symptoms or the endoscopic appearance of the nodular or SMT-like type may lead to clinically significant disease. Risk stratification according to endoscopic findings and careful surveillance are required for these lesions.