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: This study aimed to evaluate ChatGPT’s performance accuracy in responding to questions from the national dentalhygienist examination. Moreover, through an analysis of ChatGPT’s incorrect responses, this research intended to pinpoint the predominant types of errors. Methods: To evaluate ChatGPT-3.5’s performance according to the type of national examination questions, the researchers classified 200 questions of the 49th National Dental Hygienist Examination into recall, interpretation, and solving type questions. The researchers strategically modified the questions to counteract potential misunderstandings from implied meanings or technical terminology in Korea. To assess ChatGPT-3.5’s problem-solving capabilities in applying previously acquired knowledge, the questions were first converted to subjective type. If ChatGPT-3.5 generated an incorrect response, an original multiple-choice framework was provided again. Two hundred questions were input into ChatGPT-3.5 and the generated responses were analyzed.After using ChatGPT, the accuracy of each response was evaluated by researchers according to the types of questions, and the types of incorrect responses were categorized (logical, information, and statistical errors). Finally, hallucination was evaluated when ChatGPT provided misleading information by answering something that was not true as if it were true. Results: ChatGPT’s responses to the national examination were 45.5% accurate. Accuracy by question type was 60.3% for recall and 13.0% for problem-solving type questions. The accuracy rate for the subjective solving questions was 13.0%, while the accuracy for the objective questions increased to 43.5%. The most common types of incorrect responses were logical errors 65.1% of all. Of the total 102 incorrectly answered questions, 100 were categorized as hallucinations. Conclusion ChatGPT-3.5 was found to be limited in its ability to provide evidence-based correct responses to the Korean nationaldental hygiene examination. Therefore, dental hygienists in the education or clinical fields should be careful to use artificial intelligence-generated materials with a critical view.

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: Few scales are currently available to evaluate changes in hand volume. We aimed to develop a hand grading scale for quantitative assessments of dorsal hand volume with additional consideration of changes in skin texture; to validate and prove the precision and reproducibility of the new scale; and to demonstrate the presence of clinically significant differences between grades on the scale. METHODS: Five experienced plastic surgeons developed the Hand Volume Rating Scale (HVRS) and rated 91 images. Another five plastic surgeons validated the scale using 50 randomly selected images. Intra- and inter-rater agreement was calculated using the weighted kappa statistic and intraclass correlation coefficients (ICCs). Paired images were also evaluated to verify whether the scale reflected clinical differences. RESULTS: The intra-rater agreement was 0.95 (95% confidence interval, 0.922–0.974). The interrater ICCs were excellent (first rating, 0.94; second rating, 0.94). Image pairs that differed by 1, 2, and 3 grades were considered to contain clinically relevant differences in 80%, 100%, and 100% of cases, respectively, while 84% of image pairs of the same grade were found not to show clinically relevant differences. This confirmed that the scale of the HVRS corresponded to clinically relevant distinctions. CONCLUSIONS: The scale was proven to be precise, reproducible, and reflective of clinical differences.
Asian Continental Ancestry Group ; Hand ; Humans ; Plastics ; Rejuvenation ; Skin ; Skin Aging ; Surgeons ; Weights and Measures

The rate of detection of thyroid nodules and carcinomas has increased with the widespread use of ultrasonography (US), which is the mainstay for the detection and risk stratification of thyroid nodules as well as for providing guidance for their biopsy and nonsurgical treatment. The Korean Society of Thyroid Radiology (KSThR) published their first recommendations for the US-based diagnosis and management of thyroid nodules in 2011. These recommendations have been used as the standard guidelines for the past several years in Korea. Lately, the application of US has been further emphasized for the personalized management of patients with thyroid nodules. The Task Force on Thyroid Nodules of the KSThR has revised the recommendations for the ultrasound diagnosis and imaging-based management of thyroid nodules. The review and recommendations in this report have been based on a comprehensive analysis of the current literature and the consensus of experts.
Ablation Techniques ; Advisory Committees ; Biopsy ; Consensus* ; Diagnosis* ; Humans ; Korea ; Lymph Nodes ; Multidetector Computed Tomography ; Thyroid Gland* ; Thyroid Neoplasms ; Thyroid Nodule* ; Ultrasonography*

Essential tremor (ET) is one of the most common movement disorders. The prevalence of ET varies substantially among studies. In Korea, there is no well-designed epidemiological study of the prevalence of ET. Thus, we investigated the prevalence of ET in a community in Korea. Standardized interviews and in-person neurological examinations were performed in a random sample of the elderly aged 65 yr or older. Next, movement specialists attempted to diagnose ET clinically. People who showed equivocal parkinsonian features underwent dopamine transporter imaging using [123I]-FP-CIT SPECT, to differentiate ET from parkinsonism. A total of 714 subjects participated in this population-based study. Twenty six of these subjects were diagnosed as having ET. The crude prevalence of ET was 3.64 per 100 persons. Age, gender, or education period were not different between the ET patients and the non-ET subjects. The prevalence of ET was slightly lower than those reported in previous studies. Further studies including more subjects are warranted.
Age Distribution ; Aged ; Aged, 80 and over ; Essential Tremor/*diagnosis/*epidemiology ; Female ; Geriatric Assessment/*statistics & numerical data ; Humans ; Male ; Prevalence ; Republic of Korea/epidemiology ; Risk Factors ; Sex Distribution

Neurofibromatosis type I is a genetic disease caused by mutations in the neurofibromin 1 (NF1) gene. Although it is characterized by a number of distinct clinical features, including cafe au lait macules, freckling in the axillary or inguinal regions, neurofibromas, and Lisch nodules (iris harmartomas), it can affect all physiological systems in the body [1]. Neurofibromatosis-related pulmonary hypertension has also been reported, and some patients showed a poor prognosis despite having received proper medical treatment [2-4]. We herein describe a case of pulmonary hypertension in a patient with neurofibromatosis type I who had no identified risk factors of pulmonary hypertension. To our knowledge, this is the first such report in Korea.
Humans ; Hypertension ; Hypertension, Pulmonary* ; Korea ; Neurofibroma ; Neurofibromatoses* ; Neurofibromatosis 1* ; Neurofibromin 1 ; Prognosis ; Risk Factors

Neurofibromatosis type I is a genetic disease caused by mutations in the neurofibromin 1 (NF1) gene. Although it is characterized by a number of distinct clinical features, including cafe au lait macules, freckling in the axillary or inguinal regions, neurofibromas, and Lisch nodules (iris harmartomas), it can affect all physiological systems in the body [1]. Neurofibromatosis-related pulmonary hypertension has also been reported, and some patients showed a poor prognosis despite having received proper medical treatment [2-4]. We herein describe a case of pulmonary hypertension in a patient with neurofibromatosis type I who had no identified risk factors of pulmonary hypertension. To our knowledge, this is the first such report in Korea.
Humans ; Hypertension ; Hypertension, Pulmonary* ; Korea ; Neurofibroma ; Neurofibromatoses* ; Neurofibromatosis 1* ; Neurofibromin 1 ; Prognosis ; Risk Factors

Stress-induced cardiomyopathy is frequently confused with acute coronary syndromes. We encountered a 64-year old female patient with panhypopituitarism initially suspected as atypical stress-induced cardiomyopathy due to her history and initial echocardiographic findings. She was finally diagnosed as non ST-segment elevation myocardial infarction based on the findings of coronary angiogram, intravascular ultrasound and subsequent echocardiogram.
Acute Coronary Syndrome ; Cardiomyopathies ; Echocardiography ; Female ; Humans ; Hypopituitarism ; Myocardial Infarction

PURPOSE: Central venous catheterization is widely used to supply substantial amounts of fluids, total parenteral nutrition and hemodialysis in renal failure patients, as well as for measuring the central venous pressure. The most common complications encountered during central venous catheterization include catheter-related infections and subsequent sepsis. Therefore, when fever exists in patients with a central venous catheter, an immediate blood culture should be performed, and if the fever persists, an infection must be suspected and the catheter immediately removed; a culture of the catheter tip should also be performed. To date, no definite clinical details relating to this matter have been reported. METHODS: Between December 2002 and March 2005, a retrospective study was undertaken using the medical records of 85 patients. In those patients where a fever lasted for more than 8 hours, or when catheterization was no longer needed, the catheter tip cultures were sent to the microbiology laboratory. Blood cultures were also performed on 49 patients with a fever. The Chi-square method using the PC SPSS program, with P value less than 0.05 as statically significant. RESULTS: Of the 85 patients where the catheters were removed, significant microorganisms were detected 20 of the 49 with a fever. Only 5 of the remaining 36 patients had their catheters spontaneously removed. Moreover, 14 of the 20 patients with significant microorganisms were found to have kept their catheter in place for more than 14 days. Of the 49 patients with a fever, in who blood cultures were undertaken, 13 showed specific microorganisms, with 6 of these showing the same results for both their blood and catheter tip cultures, which enabled the definite diagnosis of the catheter-related infection and underlying sepsis. Various microorganisms were detected from the catheter tip cultures, including Staphylococcus species the CNS, with S. aureus being the most common, at 61.6%. CONCLUSION: A central venous catheter should be removed immediately when an infection is suspected, but early broad-spectrum antibiotics therapy should be commenced due to the time required to obtain the culture results. Moreover, even if a fever does not exist in patients with a catheter inserted for more than 14 days, infection and sepsis from the catheter should be of concern, with a more cautious approach being mandatory.
Anti-Bacterial Agents ; Catheter-Related Infections ; Catheterization ; Catheterization, Central Venous ; Catheters ; Central Venous Catheters* ; Central Venous Pressure ; Diagnosis ; Fever ; Humans ; Medical Records ; Parenteral Nutrition, Total ; Renal Dialysis ; Renal Insufficiency ; Retrospective Studies ; Sepsis ; Staphylococcus