The microbiota-gut-brain axis, which refers to the bidirectional communication pathway between gut bacteria and the central nervous system, has a profound effect on important brain processes, from the synthesis of neurotransmitters to the modulation of complex behaviors such as sociability and anxiety. Previous studies have revealed that the gut microbiota is potentially related to not only gastrointestinal disturbances, but also social impairment and repetitive behavior—core symptoms of autism spectrum disorder (ASD). Although studies have been conducted to characterize the microbial composition in patients with ASD, the results are heterogeneous. Nevertheless, it is clear that there is a difference in the composition of the gut microbiota between ASD and typically developed individuals, and animal studies have repeatedly suggested that the gut microbiota plays an important role in ASD pathophysiology. This possibility is supported by abnormalities in metabolites produced by the gut microbiota and the association between altered immune responses and the gut microbiota observed in ASD patients. Based on these findings, various attempts have been made to use the microbiota in ASD treatment. The results reported to date suggest that microbiota-based therapies may be effective for ASD, but largescale, well-designed studies are needed to confirm this.

Purpose: Emergency department (ED) is a common treatment setting for adolescents with clinically serious self-harm. Here, we investigated the clinical characteristics and trends of adolescents with self-harm who visited the ED in one Korean university hospital. We also compared patients with a single ED visit to those with multiple ED visits to identify the risk factor of repeated visits. Materials and Methods: We retrospectively identified patients aged 12 to 18 years who presented to ED for self-harm from January 2015 to December 2019, based on electronic medical records. Self-harm included all thoughts and behaviors indicating intents to harm or hurt oneself, regardless of the degree of such attempt. Results: A total of 168 individuals (male:female=31:137; average 15.99±1.64 years) presented to ED following 304 episodes (45 and 259 episodes in males and females, respectively). The number of episodes steeply increased between 2016 and 2019, and the overall number during the study showed an increasing trend (p=0.043). Repeated ED visitors with self-harm showed more history of psychiatric treatment/admission (58.3% vs. 85.4%, p=0.002; 14.2% vs. 43.9%, p<0.001), history of child abuse (32.3% vs. 53.7%, p=0.013), and familial psychiatric history (13.4% vs. 31.7%, p=0.008) compared to those with a single visit. Conclusion Among Korean adolescents, the number of ED visits and repetition of ED visits for self-harm is on the rise. For adolescents presenting to ED with self-harm, the history of psychiatric treatment/admission, child abuse, and familial psychiatric history should be properly obtained to identify the risk for multiple ED visits.

The best management strategy for angiographically intermediated coronary artery diseases remains controversial. Lesions, when coupled with spasm, can lead to catastrophic results and cardiogenic shock. We report a case of a 62-year-old man who had an intermediate coronary artery disease presenting with cardiogenic shock due to coronary spasm during a preoperative period.
Coronary Artery Disease* ; Coronary Vasospasm ; Humans ; Middle Aged ; Perioperative Period ; Preoperative Period ; Shock, Cardiogenic* ; Spasm*

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.