Physiologic dentin regeneration: its past, present, and future perspectives

Regenerative dentistry has rapidly progressed since the advancement of stem cell biology and material science. However, more emphasis has been placed on the success of tissue formation than on how well the newly generated tissue retains the original structure and function. Once dentin is lost, tertiary dentinogenesis can be induced by new odontoblastic differentiation or re-activation of existing odontoblasts. The characteristic morphology of odontoblasts generates the tubular nature of dentin, which is a reservoir of fluid, ions, and a number of growth factors, and protects the inner pulp tissue. Therefore, understanding the dynamic but delicate process of new dentin formation by odontoblasts, or odontoblast-like cells, following dentinal defects is crucial. In this regard, various efforts have been conducted to identify novel molecules and materials that can promote the regeneration of dentin with strength and longevity. In this review, we focus on recent progress in dentin regeneration research with biological molecules identified, and discuss its potential in future clinical applications

Control of mammalian G protein signaling by N-terminal acetylation and the N-end rule pathway

Rgs2, a regulator of G proteins, lowers blood pressure by decreasing signaling through Gαq. Human patients expressing Met-Leu-Rgs2 (ML-Rgs2) or Met-Arg-Rgs2 (MR-Rgs2) are hypertensive relative to people expressing wild-type Met-Gln-Rgs2 (MQ-Rgs2). We found that wild-type MQ-Rgs2 and its mutant, MR-Rgs2, were destroyed by the Ac/N-end rule pathway, which recognizes Nα-terminally acetylated (Nt-acetylated) proteins. The shortest-lived mutant, ML-Rgs2, was targeted by both the Ac/N-end rule and Arg/N-end rule pathways. The latter pathway recognizes unacetylated N-terminal residues. Thus, the Nt-acetylated Ac-MX-Rgs2 (X = Arg, Gln, Leu) proteins are specific substrates of the mammalian Ac/N-end rule pathway. Furthermore, the Ac/N-degron of Ac-MQ-Rgs2 was conditional, and Teb4, an endoplasmic reticulum (ER) membrane-embedded ubiquitin ligase, was able to regulate G protein signaling by targeting Ac-MX-Rgs2 proteins for degradation through their N^α-terminal acetyl group

FSE T2-weighted two-point Dixon technique for fat suppression in the lumbar spine: comparison with SPAIR technique

PURPOSE:Fat suppression magnetic resonance imaging (MRI) technique has been used to improve the diagnostic confidence in lumbar spine diseases. We aimed to compare T2-weighted water-fat separation technique (T2 Dixon) with spectral attenuated inversion recovery (SPAIR) image for fat suppression.METHODS:Lumbar spine MRI examinations were performed in 79 patients by using a 3.0 T machine. We compared T2 Dixon water-only image and SPAIR image for the evaluation of fat suppression quality and lesion conspicuity. For qualitative evaluation, two radiologists scored the images from Dixon and SPAIR for fat suppression uniformity and lesion conspicuity. Quantitative assessment was also performed for 39 lesions in 26 patients who had lesions in their spine bodies. Contrast ratio (CR) and contrast-to-noise ratio (CNR) were calculated by signal intensity measurement of the lesions, adjacent bodies, and background noise. The Wilcoxon’s signed-rank test and paired sample t-test were used to assess the statistical significance of qualitative and quantitative data, respectively.RESULTS:For qualitative assessment, T2 Dixon water-only image showed higher mean scores for fat suppression quality and lesion conspicuity than SPAIR (2.99±0.11 vs. 2.18±0.38 and 2.84±0.37 vs. 2.28±0.51, respectively). For quantitative measurement, the CR and CNR values of the lesions were higher on T2 Dixon than on SPAIR. Both qualitative and quantitative results showed statistically significant differences between T2 Dixon and SPAIR (P < 0.01 in all).CONCLUSION:T2 Dixon sequence was superior to SPAIR for the quality of fat suppression and for the delineation of lumbar spine lesions

Controlling Ferromagnetic Easy Axis in a Layered MoS2 Single Crystal

We report the effective methods to induce weak ferromagnetism in pristine MoS2 persisting up to room temperature with the improved transport property, which would lead to new spintronics devices. The hydrogenation of MoS2 by heating at 300 degrees C for 1 h leads to the easy axis out of plane, while the irradiation of proton with a dose of 1 x 10(13) P/cm(2) leads to the easy axis in plane. The theoretical modeling supports such magnetic easy axes.open16

Controlling ferromagnetic easy axis in a layered MoS2 single crystal

We report the effective methods to induce weak ferromagnetism in pristine MoS2 persisting up to room temperature with the improved transport property, which would lead to new spintronics devices. The hydrogenation of MoS2 by heating at 300 degrees C for 1 h leads to the easy axis out of plane, while the irradiation of proton with a dose of 1 x 10(13) P/cm(2) leads to the easy axis in plane. The theoretical modeling supports such magnetic easy axes.open116160Nsciescopu

Reliability and Validity of the Korean Version of the Childhood Trauma Questionnaire-Short Form for Psychiatric Outpatients

Objective The Childhood Trauma Questionnaire (CTQ) is perhaps the most widely used and well-studied retrospective measure of childhood abuse or neglect. This study tested the initial reliability and validity of a Korean translation of the Childhood Trauma Questionnaire (CTQ-K) among non-psychotic psychiatric outpatients.Methods The CTQ-K was administered to a total of 163 non-psychotic psychiatric outpatients at a university-affiliated training hospital. Internal consistency, four-week test-retest reliability, and validity were calculated. A portion of the participants (n=65) also completed the Trauma Assessment Questionnaire (TAQ), the Impact of Events Scale-Revised, and the Dissociative Experiences Scale-Taxon.Results Four-week test-retest reliability was high (r=0.87) and internal consistency was good (Cronbach&#39;s alpha=0.88). Each type of childhood trauma was significantly correlated with the corresponding subscale of the TAQ, thus confirming its concurrent validity. In addition, the CTQ-K total score was positively related to post-traumatic symptoms and pathological dissociation, demonstrating the convergent validity of the scale. The CTQ-K was also negatively correlated with the competence and safety subscale of the TAQ, confirming discriminant validity. Additionally, we confirmed the factorial validity by identifying a five-factor structure that explained 64% of the total variance.Conclusion Our study indicates that the CTQ-K is a measure of psychometric soundness that can be used to assess childhood abuse or neglect in Korean patients. It also supports the cross-cultural equivalence of the scale. Psychiatry Investig 2011;8:305-311This work was supported by the research fund of Hanyang University (HY-2010-I)

RELATIONSHIP BETWEEN BODY MASS INDEX AND EXTRAPYRAMIDAL SYMPTOMS IN ASIAN PATIENTS WITH SCHIZOPHRENIA: THE RESEARCH ON ASIAN PSYCHOTROPIC PRESCRIPTION PATTERNS FOR ANTIPSYCHOTICS (REAP-AP)

Background: Although an inverse relationship between body mass index (BMI) and Parkinson disease (PD) has been repeatedly reported, to our knowledge, the relationship between BMI and antipsychotic-induced extrapyramidal symptoms (EPS) has rarely been studied in patients with schizophrenia. Our study aimed to evaluate the relationship between BMI and EPS in patients with schizophrenia. Subjects and methods: Using data from the Research on Asian Psychotropic Prescription Patterns for Antipsychotics (REAP-AP) study, we compared the prevalence of EPS in 1448 schizophrenia patients stratified as underweight, normal range, overweight preobese, overweight obese I, overweight obese II, and overweight obese III according to the World Health Organization (WHO) classification system for body weight status, and with underweight, normal range, overweight at risk, overweight obese I, and overweight obese II according to the Asia-Pacific obesity classification. Results: In the first step of the WHO classification system for body weight status, adjusting for the potential effects of confounding factors, the multinomial logistic regression model revealed that underweight was significantly associated with greater rates of bradykinesia and muscle rigidity, and a lower rate of gait disturbance. In the second step of the Asia-Pacific obesity classification, adjusting for the potential effects of confounding factors, the multinomial logistic regression model revealed that underweight was significantly associated with a higher rate of muscle rigidity. Conclusion: Findings of the present study consistently revealed that underweight was associated with a greater rate of muscle rigidity in a stepwise pattern among Asian patients with schizophrenia. Although the mechanism underlying the inverse relationship between BMI and muscle rigidity cannot be sufficiently explained, it is speculated that low BMI may contribute to the development of muscle rigidity regardless of antipsychotic "typicality" and dose in patients with schizophrenia

Risks of complicated acute appendicitis in patients with psychiatric disorders

Background Acute appendicitis often presents with vague abdominal pain, which fosters diagnostic challenges to clinicians regarding early detection and proper intervention. This is even more problematic with individuals with severe psychiatric disorders who have reduced sensitivity to pain due to long-term or excessive medication use or disturbed bodily sensation perceptions. This study aimed to determine whether psychiatric disorder, psychotropic prescription, and treatment compliance increase the risks of complicated acute appendicitis. Methods The diagnosis records of acute appendicitis from four university hospitals in Korea were investigated from 2002 to 2020. A total of 47,500 acute appendicitis-affected participants were divided into groups with complicated and uncomplicated appendicitis to determine whether any of the groups had more cases of psychiatric disorder diagnoses. Further, the ratio of complicated compared to uncomplicated appendicitis in the mentally ill group was calculated regarding psychotropic dose, prescription duration, and treatment compliance. Results After adjusting for age and sex, presence of psychotic disorder (odds ratio [OR]: 1.951; 95% confidence interval [CI]: 1.218–3.125), and bipolar disorder (OR: 2.323; 95% CI: 1.194–4.520) was associated with a higher risk of having complicated appendicitis compared with absence of psychiatric disorders. Patients who are taking high-daily-dose antipsychotics, regardless of prescription duration, show high complicated appendicitis risks; High-dose antipsychotics for < 1 year (OR: 1.896, 95% CI: 1.077–3.338), high-dose antipsychotics for 1–5 years (OR: 1.930, 95% CI: 1.144–3.256). Poor psychiatric outpatient compliance was associated with a high risk of complicated appendicitis (OR: 1.664, 95% CI: 1.014–2.732). Conclusions This study revealed a close relationship in the possibility of complicated appendicitis in patients with severe psychiatric disorders, including psychotic and bipolar disorders. The effect on complicated appendicitis was more remarkable by the psychiatric disease entity itself than by psychotropic prescription patterns. Good treatment compliance and regular visit may reduce the morbidity of complicated appendicitis in patients with psychiatric disorders.This work was supported by the Technology Innovation Program (or Industrial Strategic Technology Development Program) (20004927, Upgrade of CDM based Distributed Biohealth Data Platform and Development of Verification Technology) funded by the Ministry of Trade, Industry & Energy (MOTIE, Korea), and the Bio Industrial Strategic Technology Development Program (20003883) funded by the Ministry of Trade, Industry & Energy (MOTIE, Korea), Bio & Medical Technology Development Program of the National Research Foundation of Korea funded by the Ministry of Health and Welfare, Ministry of Science and ICT, Ministry of Trade Industry and Energy (MOTIE, Korea) Disease Control and Prevention Agency (The National Project of Bio Big Data) (NRF‑2020M3E5D7085175), and Bio & Medical Technology Development Program of the National Research Foundation funded by the Ministry of Science & ICT (No. 2021M3A9E408078412)

Massive Left Atrial Calcification Associated with Mitral Valve Replacement

Calcification of the left atrium can be observed in patients with a long-lasting rheumatic heart disease. However, massive calcification of the atrial wall, so called porcelain or coconut atrium is very rare and has been generally reported only as incidental radiographic findings. We report a case of massive and firm calcifications at the left atrium in patient who underwent mitral valve replacement