Trends in acute viral gastroenteritis among children aged ≤5 years through the national surveillance system in South Korea, 2013-2019.

Acute gastroenteritis is a global public health concern. This study aimed to analyze the trend and characteristics of acute viral gastroenteritis through a national surveillance network. Enteric viruses were detected in 9510 of 31,750 (30.1%) cases assessed from 2013 to 2019 by EnterNet. The most prevalent pathogens were norovirus (15.2%) and group A rotavirus (9.7%); most infections were reported in 2017 (34.0%). Norovirus and rotavirus coinfections were the most common. Norovirus infections were prevalent among 1-year-old children (1835 out of 9510 cases) during winter, and group A rotavirus infections were common during spring. Seasonality was not observed among enteric adenovirus, astrovirus, and sapovirus. The prevalent viral genotypes detected included norovirus GII.4, enteric adenovirus F41, astrovirus genotype 1, and sapovirus GI.1. However, changes in enteric virus trends were noted during the study period. Norovirus prevalence extended into spring, and new genotypes of enteric adenovirus, astrovirus, and sapovirus were identified. These surveillance data elucidate enteric virus epidemiological characteristics.

Professional self-concept and burnout among medical school faculty in South Korea: a cross-sectional study.

BACKGROUND: Medical school faculty members have been reported to be highly likely to suffer burnout. Research is being conducted on professional self-concepts as a factor that relieves burnout in many professions. However, there is a paucity of data on the relationship between professional self-concept and burnout among medical school faculty. Professional self-concept means a perception of oneself as a member of the profession. It influences an individual's thoughts, actions, and emotions. The more positive the professional self-concept, the higher is the self-esteem in the profession, which can contribute to reducing burnout. This study aimed to investigate the professional self-concept and incidence of burnout among medical school clinical faculty members, and to ascertain the factors that affect professional self-concept with respect to burnout. METHODS: A total of 68 clinical faculty members at the Ajou University School of Medicine completed a modified form of the professional self-concept scale and the Maslach Burnout Inventory. We undertook the following statistical analyses: a descriptive analysis to understand the distribution of participants, correlation analysis to indicate associations between variables and a multiple regression analysis to examine the influence of gender, position, and specialty on professional self-concept and burnout, and the effect of each subscale of professional self-concept on burnout. RESULTS: As professional self-concept increases, burnout decreases. There was no significant difference between professional self-concept and burnout with respect to gender or field of medical specialty, while a significant difference was observed across faculty position levels. Additionally, the professional self-concept subscale, which included satisfaction and communication skill, was found to significantly affect burnout. CONCLUSIONS: This study shows that professional self-concept affects burnout. Through these results, we can infer that professional self-concept functioned to protect medical school faculty from burnout. This may be a strategy that fortifies the professional identity of medical school faculty, and it is suggested that educational programs that are directed toward this goal be established.

Age-dependent gait abnormalities in mice lacking the Rnf170 gene linked to human autosomal-dominant sensory ataxia.

Really interesting new gene (RING) finger protein 170 (RNF170) is an E3 ubiquitin ligase known to mediate ubiquitination-dependent degradation of type-I inositol 1,4,5-trisphosphate receptors (ITPR1). It has recently been demonstrated that a point mutation of RNF170 gene is linked with autosomal-dominant sensory ataxia (ADSA), which is characterized by an age-dependent increase of walking abnormalities, a rare genetic disorder reported in only two families. Although this mutant allele is known to be dominant, the functional identity thereof has not been clearly established. Here, we generated mice lacking Rnf170 (Rnf170(-/-)) to evaluate the effect of its loss of function in vivo. Remarkably, Rnf170(-/-) mice began to develop gait abnormalities in old age (12 months) in the form of asynchronous stepping between diagonal limb pairs with a fixed step sequence during locomotion, while age-matched wild-type mice showed stable gait patterns using several step sequence repertoires. As reported in ADSA patients, they also showed a reduced sensitivity for proprioception and thermal nociception. Protein blot analysis revealed that the amount of Itpr1 protein was significantly elevated in the cerebellum and spinal cord but intact in the cerebral cortex in Rnf170(-/-) mice. These results suggest that the loss of Rnf170 gene function mediates ADSA-associated phenotypes and this gives insights on the cure of patients with ADSA and other age-dependent walking abnormalities.

Direct selective leaching of lithium from industrial-grade black mass of waste lithium-ion batteries containing LiFePO4 cathodes.

Demand for lithium-ion batteries (LIBs) is projected to maintain unprecedented acceleration for decades, towards satisfying international climate and source objectives. LIB wastes pose a threat to the environment, but also may be considered a strategic, high-grade resource. Yet, recycling the black mass of waste LIBs, which contains plastic, C, Li, Fe, Ni, Co, Mn, Cu, and Al, is very complex. Herein, the direct selective leaching of Li from the industrial-grade black mass powder of waste LIBs is proposed for the first time. Results demonstrated that the leaching efficiency of Li is shown to exceed 97%, while other metals remain below 1%. The mechanism of selective leaching was also investigated in this study. Under the experimental conditions, Fe is not leached out and remains in the form of solid FePO4. As for other impurity metal elements, they are removed from the solution due to the alkaline environment of the post-leaching solution and the adsorption effect of the anodic carbon. Furthermore, the alkaline post-leaching solution can avoid the neutralizing stage before the precipitation of lithium salts. This highly efficient and Li-selective leaching strategy offers a broadly applicable approach to reclaiming critical energy minerals from the black mass of wasted LIBs.

Thalamic T-type Ca²+ channels mediate frontal lobe dysfunctions caused by a hypoxia-like damage in the prefrontal cortex.

Hypoxic damage to the prefrontal cortex (PFC) has been implicated in the frontal lobe dysfunction found in various neuropsychiatric disorders. The underlying subcortical mechanisms, however, have not been well explored. In this study, we induced a PFC-specific hypoxia-like damage by cobalt-wire implantation to demonstrate that the role of the mediodorsal thalamus (MD) is critical for the development of frontal lobe dysfunction, including frontal lobe-specific seizures and abnormal hyperactivity. Before the onset of these abnormalities, the cross talk between the MD and PFC nuclei at theta frequencies was enhanced. During the theta frequency interactions, burst spikes, known to depend on T-type Ca(2+) channels, were increased in MD neurons. In vivo knockout or knockdown of the T-type Ca(2+) channel gene (Ca(V)3.1) in the MD substantially reduced the theta frequency MD-PFC cross talk, frontal lobe-specific seizures, and locomotor hyperactivity in this model. These results suggest a two-step model of prefrontal dysfunction in which the response to a hypoxic lesion in the PFC results in abnormal thalamocortical feedback driven by thalamic T-type Ca(2+) channels, which, in turn, leads to the onset of neurological and behavioral abnormalities. This study provides valuable insights into preventing the development of neuropsychiatric disorders arising from irreversible PFC damage.

Real time measurement of myocardial oxygen dynamics during cardiac ischemia-reperfusion of rats.

Because oxygen plays a critical role in the pathophysiology of myocardial injury during subsequent reperfusion, as well as ischemia, the accurate measurement of myocardial oxygen tension is crucial for the assessment of myocardial viability by ischemia-reperfusion (IR) injury. Therefore, we utilized a sol-gel derived electrochemical oxygen microsensor to monitor changes in oxygen tension during myocardial ischemia-reperfusion. We also analyzed differences in oxygen tension recovery in post-ischemic myocardium depending on ischemic time to investigate the correlation between recovery parameters for oxygen tension and the severity of IR injury. An oxygen sensor was built using a xerogel-modified platinum microsensor and a coiled Ag/AgCl reference electrode. Rat hearts were randomly divided into 5 groups: control (0 min ischemia), I-10 (10 min ischemia), I-20 (20 min ischemia), I-30 (30 min ischemia), and I-40 (40 min ischemia) groups (n = 3 per group, respectively). After the induction of ischemia, reperfusion was performed for 60 min. As soon as the ischemia was initiated, oxygen tension rapidly declined to near zero levels. When reperfusion was initiated, the changes in oxygen tension depended on ischemic time. The normalized peak level of oxygen tension during the reperfusion episode was 188 ± 27 in group I-10, 120 ± 24 in group I-20, 12.5 ± 10.6 in group I-30, and 1.24 ± 1.09 in group I-40 (p < 0.001, n = 3, respectively). After 60 min of reperfusion, the normalized restoration level was 129 ± 30 in group I-10, 88 ± 4 in group I-20, 3.40 ± 4.82 in group I-30, and 0.99 ± 0.94 in group I-40 (p < 0.001, n = 3, respectively). The maximum and restoration values of oxygen tension in groups I-30 and I-40 after reperfusion were lower than pre-ischemic values. In particular, oxygen tension in the I-40 group was not recovered at all. These results were also demonstrated by TTC staining. We suggest that these recovery parameters could be utilized as an index of tissue injury and severity of ischemia. Therefore, quantitative measurements of oxygen tension dynamics in the myocardium would be helpful for evaluation of the cardioprotective effects of therapeutic treatments such as drug administration.

Non-invasive screening of progressive joint defects in the Type II collagen-induced arthritis animal model using radiographic paw images.

OBJECTIVE: This study presents a method for non-invasive screening of progressive arthritic reactions in a representative rheumatoid arthritis (RA) animal model of Type II collagen-induced arthritis (CIA). MATERIALS: Seventeen male DBA/1J mice (9 weeks old) were used for the control group (seven) and the CIA group (ten). TREATMENT: The CIA model was induced by the injection of a Type II collagen and incomplete Freund's adjuvant emulsion. METHODS: Arthritic reactions including joint space narrowing (JSN), bone erosion, inflammation, and physiological defects were observed using five non-invasive methods. The degrees of JSN and bone erosion were quantified using macro-radiographs of specific joints and bones, while the severity of inflammation was evaluated by changes in paw volume and visual scoring of edema and erythema. RESULTS: Significant differences were observed in JSN (≤48.29%, p < 0.0001), bone erosion (78.30%, p < 0.0001), grip strength (p < 0.05), and inflammation (91.67% in edema and 194.12% increase in paw volume, p < 0.001) between the CIA group and the controls. The relationships between factors exhibited significant positive correlations (R ≥ 0.9229, p < 0.05) between radiographic parameters, with symmetries of ≥0.9062 (p < 0.05) for JSN and ≥ 0.8575 (p < 0.001) for bone erosion, 0.8770 (p < 0.0001) for inflammatory parameters, and ≥0.9527 (p < 0.0001) for radiographic and non-radiographic parameters. CONCLUSIONS: Our non-invasive radiographic and non-radiographic methods of documentation were both acceptable for screening joint defects during RA progression. In addition, the results of this study may be useful for monitoring the progression of joint pathology in RA diseases.

The laboratory test procedure to confirm rotavirus vaccine infection in severe complex immunodeficiency patients.

The rotavirus vaccine is a live vaccine, and there is a possibility of infection by the virus strain used in the vaccine. We investigated the process of determining whether an infection was caused by the vaccine strain in a severe complex immunodeficiency (SCID) patient with rotavirus infection. The patient was vaccinated with RotaTeq prior to being diagnosed with SCID. The testing process was conducted in the following order: confirming rotavirus infection, determining its genotype, and confirming the vaccine strain. Rotavirus infection was confirmed through enzyme immunoassay and VP6 gene detection. G1 and P[8] were identified by multiplex polymerase chain reaction for the genotype, and G3 was further identified using a single primer. By detecting the fingerprint gene (WC3) of RotaTeq, it was confirmed that the detected virus was the vaccine strain. Genotypes G1 and P[8] were identified, and the infection was suspected of having been caused by rotavirus G1P[8]. G1P[8] is the most commonly detected genotype worldwide and is not included in the recombinant strains used in vaccines. Therefore, the infection was confirmed to have been caused by the vaccine strain by analyzing the genetic relationship between VP4 and VP7. Rotavirus infection by the vaccine strain can be identified through genotyping and fingerprint gene detection. However, genetic linkage analysis will also help to identify vaccine strains.

Molecular laterality encodes stress susceptibility in the medial prefrontal cortex.

Functional lateralization of the prefrontal cortex has been implicated in stress and emotional disorders, yet underlying gene expression changes remains unknown. Here, we report molecular signatures lateralized by chronic social defeats between the two medial prefrontal cortices (mPFCs). Stressed mice show 526 asymmetrically expressed genes between the mPFCs. This cortical asymmetry selectively occurs in stressed mice with depressed social activity, but not in resilient mice with normal behavior. We have isolated highly asymmetric genes including connective tissue growth factor (CTGF), a molecule that modulates wound healing at the periphery. Knockdown of CTGF gene in the right mPFC by shRNA led to a stress-resistant behavioral phenotype. Overexpression of CTGF in the right mPFC using viral transduction induces social avoidance while the left mPFC thereof prevent stress-induced social avoidance. Our study provides a molecular window into the mechanism of stress-induced socioemotional disorders, which can pave the way for new interventions by targeting cortical asymmetry.

Cerebellar 5HT-2A receptor mediates stress-induced onset of dystonia.

Stress is a key risk factor for dystonia, a debilitating motor disorder characterized by cocontractions of muscles leading to abnormal body posture. While the serotonin (5HT) system is known to control emotional responses to stress, its role in dystonia remains unclear. Here, we reveal that 5HT neurons in the dorsal raphe nuclei (DRN) send projections to the fastigial deep cerebellar nuclei (fDCN) and that photostimulation of 5HT-fDCN induces dystonia in wild-type mice. Moreover, we report that photoinhibition of 5HT-fDCN reduces dystonia in a1A tot/tot mice, a genetic model of stress-induced dystonia, and administration of a 5HT-2A receptor inverse agonist (MDL100907; 0.1 to 1 mg/kg) or shRNA-mediated knockdown of the ht2ar gene in fDCN can notably reduce the onset of dystonia in a1A tot/tot mice. These results support the serotonin theory of dystonia and suggest strategies for alleviating symptoms in human patients by blocking 5HT-2A receptors.

Nationwide seroprevalence of hepatitis A in South Korea from 2009 to 2019.

Hepatitis A, an acute type of hepatitis caused by the hepatitis A virus, occurs worldwide. Following the 2009 hepatitis A epidemic in South Korea, patient outbreak reports were collectively converted to an "all-patient report" in 2011, and national immunization programs were introduced for children in 2015. In this study, we aimed to analyze the changes and characteristics of hepatitis A antibody titers in South Korea following the epidemic. The results of hepatitis A antibody tests performed at clinical laboratories from 2009 to 2019 were analyzed based on year, age, region, sex, and medical institution. The average 2009-2018 positive anti-hepatitis A virus immunoglobulin G rate was 51.8%, but it increased (56.06%) in 2019. Significantly different antibody-positive rates were observed based on age: <10 years, 54.5%; 20-29 years, 19.5%; ≥50 years, almost 100%. The positive rate of individuals in their teens and 20s gradually increased, whereas that of those in their 30s and 40s gradually decreased. Males had higher antibody-positive rates than females, and samples from higher-level general hospitals exhibited higher antibody rates. The positive anti-hepatitis A virus immunoglobulin M rates gradually decreased after 2009 and were <1% after 2012. However, a high positive rate of 3.69% was observed in 2019 when there was an epidemic. Anti-hepatitis A virus immunoglobulin G-positive rates were similar throughout the year, but the anti-hepatitis A virus immunoglobulin M-positive rates increased from January, peaked in April, and decreased from July, exhibiting distinct seasonality. This is considered to be related to groundwater pollution during the spring drought season. The introduction of the "all-patient report" and national vaccination program for children has had an effective influence on hepatitis A management. However, for hepatitis A prevention, policy considerations for high-risk age groups with low antibody-positive rates will be necessary.

The mediating effect of resilience on the relationship between the academic burnout and psychological well-being of medical students.

PURPOSE: This study aimed to examine the medicating effect of resilience on the relationship between academic burnout and psychological well-being of medical students. METHODS: The participants were a group of 97 medical students. Scales measuring Maslach Burnout Inventory-Student Survey, Ryff's Psychological Well-Being, and Korean Resilience Quotient-53 were utilized. The data were analyzed by descriptive statistics, correlation analysis, t-test, and multiple regression analyses using IBM SPSS ver. 22.0 (IBM Corp., Armonk, USA). RESULTS: According to the study results, the medical students' psychological well-being was negatively correlated with their academic burnout and positively correlated with their resilience; the degree of academic burnout experienced by the first and second year preclinical students was greater than that experienced by the third and fourth year clinical students; the male students' average score for cynicism was higher than that of the female students; and the significant effects of academic burnout on the medical students' psychological well-being were mediated by resilience. CONCLUSION: It was confirmed that medical students' academic burnout and resilience are significant factors that explain their psychological well-being; resilience is also an important variable in improving psychological well-being. This suggests that education and counseling support are needed to increase medical students' resilience in order to increase their psychological well-being.

Detection and Isolation of SARS-CoV-2 in Serum, Urine, and Stool Specimens of COVID-19 Patients from the Republic of Korea.

OBJECTIVES: Coronavirus Disease-19 (COVID-19) is a respiratory infection characterized by the main symptoms of pneumonia and fever. It is caused by the novel coronavirus severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2), which is known to spread via respiratory droplets. We aimed to determine the rate and likelihood of SARS-CoV-2 transmission from COVID-19 patients through non-respiratory routes. METHODS: Serum, urine, and stool samples were collected from 74 hospitalized patients diagnosed with COVID-19 based on the detection of SARS-CoV-2 in respiratory samples. The SARS-CoV-2 RNA genome was extracted from each specimen and real-time reverse transcription polymerase chain reaction performed. CaCo-2 cells were inoculated with the specimens containing the SARS-COV-2 genome, and subcultured for virus isolation. After culturing, viral replication in the cell supernatant was assessed. RESULTS: Of the samples collected from 74 COVID-19 patients, SARS-CoV-2 was detected in 15 serum, urine, or stool samples. The virus detection rate in the serum, urine, and stool samples were 2.8% (9/323), 0.8% (2/247), and 10.1% (13/129), and the mean viral load was 1,210 ± 1,861, 79 ± 30, and 3,176 ± 7,208 copy/µL, respectively. However, the SARS-CoV-2 was not isolated by the culture method from the samples that tested positive for the SARS-CoV-2 gene. CONCLUSION: While the virus remained detectable in the respiratory samples of COVID-19 patients for several days after hospitalization, its detection in the serum, urine, and stool samples was intermittent. Since the virus could not be isolated from the SARS-COV-2-positive samples, the risk of viral transmission via stool and urine is expected to be low.

Observations of the Effects of Angiotensin II Receptor Blocker on Angiotensin II-Induced Morphological and Mechanical Changes in Renal Tubular Epithelial Cells Using Atomic Force Microscopy.

OBJECTIVE: Angiotensin II (Ang II) plays a profibrotic role in the kidneys. Although many pathways of Ang II have been discovered, the morphological and mechanical aspects have not been well investigated. We observed the changes in tubular epithelial cells (TECs) after Ang II treatment with or without Ang II receptor blockers (ARBs) using atomic force microscopy (AFM). METHODS: TECs were stimulated with Ang II with or without telmisartan, PD123319, and blebbistatin. AFM was performed to measure the cellular stiffness, cell volume, and cell surface roughness. Epithelial to mesenchymal transition markers were determined via immunocytochemistry. RESULTS: After Ang II stimulation, cells transformed to a flattened and elongated mesenchymal morphology. Cell surface roughness and volume significantly increased in Ang II treated TECs. Ang II also induced an increase in phospho-myosin light chain and F-actin and a decrease in E-cadherin. Ang II coincubation with either telmisartan or blebbistatin attenuated these Ang II-induced changes. CONCLUSION: We report, for the first time, the use of AFM in directly observing the changes in TECs after Ang II treatment with or without ARBs. Simultaneously, we successfully measured the selective effect of PD123319 or blebbistatin. AFM could be a noninvasive evaluating strategy for cellular processes in TECs.

Disruption of Ninjurin1 Leads to Repetitive and Anxiety-Like Behaviors in Mice.

Over the last few decades, molecular neurobiology has uncovered many genes whose deficiency in mice results in behavioral traits associated with human neuropsychiatric disorders such as autism, obsessive-compulsive disorder (OCD), and schizophrenia. However, the etiology of these common diseases remains enigmatic with the potential involvement of a battery of genes. Here, we report abnormal behavioral phenotypes of mice deficient in a cell adhesion molecule Ninjurin 1 (Ninj1), which are relevant to repetitive and anxiety behaviors of neuropsychiatric disorders. Ninj1 knockout (KO) mice exhibit compulsive grooming-induced hair loss and self-made lesions as well as increased anxiety-like behaviors. Histological analysis reveals that Ninj1 is predominantly expressed in cortico-thalamic circuits, and neuron-specific Ninj1 conditional KO mice manifest aberrant phenotypes similar to the global Ninj1 KO mice. Notably, the brains of Ninj1 KO mice display altered synaptic transmission in thalamic neurons as well as a reduced number of functional synapses. Moreover, the disruption of Ninj1 leads to glutamatergic abnormalities, including increased ionotropic glutamate receptors but reduced glutamate levels. Furthermore, chronic treatment with fluoxetine, a drug reportedly ameliorates compulsive behaviors in mice, prevents progression of hair loss and alleviates the compulsive grooming and anxiety-like behavior of Ninj1 KO mice. Collectively, our results suggest that Ninj1 could be involved in neuropsychiatric disorders associated with impairments of repetitive and anxiety behaviors.

Genome Sequence of Bacteriophage GG32, Which Can Infect both Salmonella enterica Serovar Typhimurium and Escherichia coli O157:H7.

We report here a new virulent Salmonella enterica serovar Typhimurium (S Typhimurium) bacteriophage, GG32, which was isolated from the Guem River in the Republic of Korea. The strain can infect both S Typhimurium and Escherichia coli (E. coli) O157:H7 and may be a good candidate for a bio-control agent.

Complete Genome Sequence of Bacteriophage MA12, Which Infects both Campylobacter jejuni and Salmonella enterica Serovar Enteritidis.

Here, we announce the complete genome sequence of Salmonella enterica serovar Enteritidis (S Enteritidis) bacteriophage MA12, a 41-Kb chromosome. The strain can infect both Campylobacter jejuni (C. jejuni) and S Enteritidis and can be used in phage therapy experiments with poultry and poultry meat.

[Learning objectives achievement in ethics education for medical school students].

PURPOSE: This study aimed to examine the necessity for research ethics and learning objectives in ethics education at the undergraduate level. METHODS: A total of 393 fourth-year students, selected from nine medical schools, participated in a survey about learning achievement and the necessity for it. RESULTS: It was found that the students had very few chances to receive systematic education in research ethics and that they assumed that research ethics education was provided during graduate school or residency programs. Moreover, the students showed a relatively high learning performance in life ethics, while learning achievement was low in research ethics. CONCLUSION: Medical school students revealed low interest in and expectations of research ethics in general; therefore, it is necessary to develop guidelines for research ethics in the present situation, in which medical education mainly focuses on life ethics.

Left brain cortical activity modulates stress effects on social behavior.

When subjected to stress, some individuals develop maladaptive symptoms whereas others retain normal behavior. The medial prefrontal cortex (mPFC) is known to control these adaptive responses to stress. Here, we show that mPFC neurons in the left hemisphere control stress effects on social behavior. Mice made socially avoidant by the stress of chronic social defeats showed depressed neural activity in the left mPFC. Photoactivation of these neurons reversed social avoidance and restored social activity. Despite social defeats, resilient mice with normal sociability showed normal firing rates in the left mPFC; however, photoinhibition of these neurons induced social avoidance. The same photomodulation administered to the right mPFC caused no significant effects. These results explain how stressed individuals develop maladaptive behaviors through left cortical depression, as reported in mood and anxiety disorders.

Characterization of Salmonella enterica serovar Typhimurium and Salmonella enterica serovar 4,[5],12:i:- isolates from pigs presenting with diarrhea in Korea.

Between 2011 and 2012, a total of 896 pig fecal samples were collected from nine provinces in Korea, and 50 salmonella enterica susp. enterica serovar Typhimurium (S. Typhimurium) was isolated. The characteristics of the 50 strains were analyzed, and 4 strains were identified as Salmonella enterica subsp. enterica serovar 4,[5],12:i:-. Salmonella 4,[5],12:i:- could not be distinguished from S. Typhimurium through phage typing, antimicrobial resistance testing or multiple-locus variable-number tandem repeat analysis (MLVA). However, among the four Salmonella 4,[5],12:i:- strains, one (KVCC-BA1400078) was identified as a Salmonella 4,[5],12:i:- clone isolated from humans in the United States, and another (KVCC-BA1400080) was identified as DT193, which has been primarily isolated from humans and animals in European countries. The presence of Salmonella 4,[5],12:i:- in Korea poses a significant threat of horizontal transfer between pigs and humans.