Clinical and Laboratory Factors Associated with Symptom Development in Asymptomatic COVID-19 Patients at the Time of Diagnosis.

In preparation for the surge of coronavirus disease 2019 (COVID-19), it is crucial to allocate medical resources efficiently for distinguishing people who remain asymptomatic until the end of the disease. Between January 27, 2020, and April 21, 2020, 517 COVID-19 cases from 13 healthcare facilities in Gyeonggi province, Korea, were identified out of which the epidemiologic and clinical information of 66 asymptomatic patients at the time of diagnosis were analyzed retrospectively. An exposure-diagnosis interval within 7 days and abnormal aspartate aminotransferase levels were identified as characteristic symptom development in asymptomatic COVID-19 patients. If asymptomatic patients without these characteristics at the time of diagnosis could be differentiated early, more medical resources could be secured for mild or moderate cases in this COVID-19 surge.

Aberrant growth of the anterior cranial base relevant to severe midface hypoplasia of Apert syndrome.

BACKGROUND: A 9-year-old male showed severe defects in midface structures, which resulted in maxillary hypoplasia, ocular hypertelorism, relative mandibular prognathism, and syndactyly. He had been diagnosed as having Apert syndrome and received a surgery of frontal calvaria distraction osteotomy to treat the steep forehead at 6 months old, and a surgery of digital separation to treat severe syndactyly of both hands at 6 years old. Nevertheless, he still showed a turribrachycephalic cranial profile with proptosis, a horizontal groove above supraorbital ridge, and a short nose with bulbous tip. METHODS: Fundamental aberrant growth may be associated with the cranial base structure in radiological observation. RESULTS: The Apert syndrome patient had a shorter and thinner nasal septum in panthomogram, PA view, and Waters' view; shorter zygomatico-maxillary width (83.5 mm) in Waters' view; shorter length between the sella and nasion (63.7 mm) on cephalogram; and bigger zygomatic axis angle of the cranial base (118.2°) in basal cranial view than a normal 9-year-old male (94.8 mm, 72.5 mm, 98.1°, respectively). On the other hand, the Apert syndrome patient showed interdigitating calcification of coronal suture similar to that of a normal 30-year-old male in a skull PA view. CONCLUSION: Taken together, the Apert syndrome patient, 9 years old, showed retarded growth of the anterior cranial base affecting severe midface hypoplasia, which resulted in a hypoplastic nasal septum axis, retruded zygomatic axes, and retarded growth of the maxilla and palate even after frontal calvaria distraction osteotomy 8 years ago. Therefore, it was suggested that the severe midface hypoplasia and dysostotic facial profile of the present Apert syndrome case are closely relevant to the aberrant growth of the anterior cranial base supporting the whole oro-facial and forebrain development.

Trichostatin A induces apoptosis in oral squamous cell carcinoma cell lines independent of hyperacetylation of histones.

AIM OF STUDY: To investigate the apoptotic event of trichostatin A (TSA) and its associated mechanism in oral squamous cell carcinoma (OSCC) lines. MATERIALS AND METHODS: HSC-3 and Ca9.22 cell lines were evaluated using a trypan blue exclusion assay, histone isolation, soft agar assay, live/dead assay, 4%,6-diamidino-2-phenylindole staining, JC-1 mitochondrial membrane potential (MMP) assay, and Western blot analysis to demonstrate the anticancer activity of TSA. RESULTS: TSA decreased OSCC cell viability and proliferation without affecting the histone acetylation. TSA-induced caspase-dependent or -independent apoptosis according to cell types, TSA enhanced the expression levels of Bim protein by dephosphorylating ERK1/2 pathway in HSC-3 cells. TSA also damaged MMP and increased cytosolic apoptosis-inducing factor (AIF) in Ca9.22 cells. CONCLUSION: The present study suggests that TSA may be a potential anticancer drug candidate for the treatment of OSCC through the induction of apoptosis.

Recombinant human IGF-1 produced by transgenic plant cell suspension culture enhances new bone formation in calvarial defects.

Transgenic plant cell suspension culture systems have been utilized extensively as convenient and efficient expression systems for the production of recombinant human growth factors. We produced insulin-like growth factor-1 using a plant suspension culture system (p-IGF-1) and explored its effect on new bone formation in calvarial defects. We also compared the bone regenerating potential of p-IGF-1 with commercial IGF-1 derived from Escherichia coli (e-IGF-1). Male C57BL/6 mice underwent calvarial defect surgery, and the defects were loaded with absorbable collagen sponge (ACS) only (ACS group) or ACS impregnated with 13µg of p-IGF-1 (p-IGF-1 group) or e-IGF-1 (e-IGF-1 group). The sham group did not receive any treatment with ACS or IGFs after surgery. Live µCT and histological analyses showed critical-sized bone defects in the sham group, whereas greater bone formation was observed in the p-IGF-1 and e-IGF-1 groups than the ACS group both 5 and 10weeks after surgery. Bone mineral density, bone volume, and bone surface values were also higher in the IGF groups than in the ACS group. Local delivery of p-IGF-1 or e-IGF-1 more greatly enhanced the expression of osteoblast-specific markers, but inhibited osteoclast formation, in newly formed bone compared with ACS control group. Specifically, p-IGF-1 treatment induced higher expression of alkaline phosphatase, osteocalcin, and osteopontin in the defect site than did e-IGF-1. Furthermore, treatment with p-IGF-1, but not e-IGF-1, increased mineralization of MC3T3-E1 cells, with the attendant upregulation of osteogenic marker genes. Collectively, our findings suggest the potential of p-IGF-1 in promoting the processes required for bone regeneration.

The genial tubercle: A prospective novel landmark for the diagnosis of mandibular asymmetry.

INTRODUCTION: Identifying menton (Me) on posteroanterior cephalograms and three-dimensional (3D) cone-beam computed tomography (CBCT) images is difficult, because the midpoint of the symphyseal area is not identifiable after the mandibular symphysis fuses at an early age. The aim of this study was to evaluate the reliability of the identification of the genial tubercle (GT) in patients with mandibular asymmetry and to compare it with that of the traditional landmark, Me. METHODS: The samples comprised 20 CBCT images of adults with mandibular asymmetry. Two examiners performed the identifications and measurements. Me and GT were marked, and the anteroposterior, vertical, and transverse distances to the three reference planes were measured on 3D-reconstructed CBCT images. The intra- and inter-examiner reliability of landmark identification of Me and GT were assessed using the intraclass correlation coefficient (ICC) and Bland-Altman plots. RESULTS: The Me and GT landmarks showed excellent reliability (ICC ≥ 0.993) three-dimensionally. In the transverse evaluation, the ICC values of the GT (range, 0.997-0.999) tended to be slightly higher than those of Me (range, 0.993-0.996). In the Bland-Altman plots for the two separate assessments, Me showed a maximum error of 1.76 mm in the transverse direction, whereas the GT showed a maximum error of 0.96 mm in the 95% limit. CONCLUSIONS: Our results suggest that both Me and GT are clinically reliable and equally useful landmarks for the evaluation of mandibular asymmetry on CBCT images.

Alterations of papilla dimensions after orthodontic closure of the maxillary midline diastema: a retrospective longitudinal study.

PURPOSE: The aim of this study was to evaluate alterations of papilla dimensions after orthodontic closure of the diastema between maxillary central incisors. METHODS: Sixty patients who had a visible diastema between maxillary central incisors that had been closed by orthodontic approximation were selected for this study. Various papilla dimensions were assessed on clinical photographs and study models before the orthodontic treatment and at the follow-up examination after closure of the diastema. Influences of the variables assessed before orthodontic treatment on the alterations of papilla height (PH) and papilla base thickness (PBT) were evaluated by univariate regression analysis. To analyze potential influences of the 3-dimensional papilla dimensions before orthodontic treatment on the alterations of PH and PBT, a multiple regression model was formulated including the 3-dimensional papilla dimensions as predictor variables. RESULTS: On average, PH decreased by 0.80 mm and PBT increased after orthodontic closure of the diastema (P<0.01). Univariate regression analysis revealed that the PH (P=0.002) and PBT (P=0.047) before orthodontic treatment influenced the alteration of PH. With respect to the alteration of PBT, the diastema width (P=0.045) and PBT (P=0.000) were found to be influential factors. PBT before the orthodontic treatment significantly influenced the alteration of PBT in the multiple regression model. CONCLUSIONS: PH decreased but PBT increased after orthodontic closure of the diastema. The papilla dimensions before orthodontic treatment influenced the alterations of PH and PBT after closure of the diastema. The PBT increased more when the diastema width before the orthodontic treatment was larger.

Glucose oxidase facilitates osteogenic differentiation and mineralization of embryonic stem cells through the activation of Nrf2 and ERK signal transduction pathways.

Nuclear factor (erythroid-derived 2)-like 2 (Nrf2)/heme oxygenase-1 (HO-1) signal is known to play important roles in controlling bone homeostasis. This study examined how oxidative stress affects the mineralization of embryonic stem (ES) cells by exposing them to glucose oxidase (GO), which continuously generates H2O2 at low concentrations. The roles of Nrf2/HO-1 and mitogen-activated protein kinases on osteogenesis in GO-exposed ES cells were also investigated. GO treatment at relatively low concentrations did not change the viability of ES cells, whereas it enhanced osteogenic differentiation and mineralization in the cells. GO treatment (1 mU/ml) augmented the induction of runt-related transcription factor 2 (Runx2), Nrf2, and HO-1 in ES cells. GO-mediated acceleration of Runx2 expression and mineralization was inhibited either by Nrf2 knockdown or by treating with 5 µM PD98059, an inhibitor of phospho-extracellular signal-regulated kinase (p-ERK). The GO-stimulated mineralization was also suppressed by treating the cells with reduced glutathione or catalase, but not by superoxide dismutase or N-acetyl-cysteine. Collectively, our results demonstrate that a mild oxidative stress activates Nrf2/HO-1 signaling and an ERK-mediated pathway, and facilitates the mineralization of ES cells with a corresponding increase in Runx2.

Regional Differences of Proteins Expressing in Adipose Depots Isolated from Cows, Steers and Bulls as Identified by a Proteomic Approach.

Adipose tissue in the loin muscle area of beef cattle as a marbling factor is directly associated with beef quality. To elucidate whether properties of proteins involved in depot specific adipose tissue were sex-dependent, we analyzed protein expression of intramuscular adipose tissue (IMAT) and omental adipose tissue (OMAT) from Hanwoo cows, steers, and bulls of Korean native beef cattle by liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomic analysis, quantitative polymerase chain reaction (PCR) and western blot analysis. Two different adipose depots (i.e. intramuscular and omental) were collected from cows (n = 7), steers (n = 7), or bulls (n = 7). LC-MS/MS revealed a total of 55 and 35 proteins in IMAT and OMAT, respectively. Of the 55 proteins identified, 44, 40, and 42 proteins were confirmed to be differentially expressed in IMAT of cows, steers, and bulls, respectively. In OMAT of cows, steers, and bulls, 33, 33, and 22 were confirmed to be differentially expressed, respectively. Tropomyosin (TPM) 1, TPM 2, and TPM3 were subjected to verification by quantitative PCR and western blot analysis in IMAT and OMAT of Hanwoo cows, steers, and bulls as key factors closely associated with muscle development. Both mRNA levels and protein levels of TPM1, TPM2, and TPM3 in IMAT were lower in bulls compared to in cows or steers suggesting that they were positively correlated with marbling score and quality grade. Our results may aid the regulation of marbling development and improvement of meat quality grades in beef cattle.

Proteomic Assessment of the Relevant Factors Affecting Pork Meat Quality Associated with Longissimus dorsi Muscles in Duroc Pigs.

Meat quality is a complex trait influenced by many factors, including genetics, nutrition, feeding environment, animal handling, and their interactions. To elucidate relevant factors affecting pork quality associated with oxidative stress and muscle development, we analyzed protein expression in high quality longissimus dorsi muscles (HQLD) and low quality longissimus dorsi muscles (LQLD) from Duroc pigs by liquid chromatographytandem mass spectrometry (LC-MS/MS)-based proteomic analysis. Between HQLD (n = 20) and LQLD (n = 20) Duroc pigs, 24 differentially expressed proteins were identified by LC-MS/MS. A total of 10 and 14 proteins were highly expressed in HQLD and LQLD, respectively. The 24 proteins have putative functions in the following seven categories: catalytic activity (31%), ATPase activity (19%), oxidoreductase activity (13%), cytoskeletal protein binding (13%), actin binding (12%), calcium ion binding (6%), and structural constituent of muscle (6%). Silver-stained image analysis revealed significant differential expression of lactate dehydrogenase A (LDHA) between HQLD and LQLD Duroc pigs. LDHA was subjected to in vitro study of myogenesis under oxidative stress conditions and LDH activity assay to verification its role in oxidative stress. No significant difference of mRNA expression level of LDHA was found between normal and oxidative stress condition. However, LDH activity was significantly higher under oxidative stress condition than at normal condition using in vitro model of myogenesis. The highly expressed LDHA was positively correlated with LQLD. Moreover, LDHA activity increased by oxidative stress was reduced by antioxidant resveratrol. This paper emphasizes the importance of differential expression patterns of proteins and their interaction for the development of meat quality traits. Our proteome data provides valuable information on important factors which might aid in the regulation of muscle development and the improvement of meat quality in longissimus dorsi muscles of Duroc pigs under oxidative stress conditions.

Enhanced compatibility and initial stability of Ti6Al4V alloy orthodontic miniscrews subjected to anodization, cyclic precalcification, and heat treatment.

OBJECTIVE: To evaluate the bioactivity, and the biomechanical and bone-regenerative properties of Ti6Al4V miniscrews subjected to anodization, cyclic precalcification, and heat treatment (APH treatment) and their potential clinical use. METHODS: The surfaces of Ti6Al4V alloys were modified by APH treatment. Bioactivity was assessed after immersion in simulated body fluid for 3 days. The hydrophilicity and the roughness of APH-treated surfaces were compared with those of untreated (UT) and anodized and heat-treated (AH) samples. For in vivo tests, 32 miniscrews (16 UT and 16 APH) were inserted into 16 Wistar rats, one UT and one APH-treated miniscrew in either tibia. The miniscrews were extracted after 3 and 6 weeks and their osseointegration (n = 8 for each time point and group) was investigated by surface and histological analyses and removal torque measurements. RESULTS: APH treatment formed a dense surface array of nanotubular TiO2 layer covered with a compact apatite-like film. APH-treated samples showed better bioactivity and biocompatibility compared with UT and AH samples. In vivo, APH-treated miniscrews showed higher removal torque and bone-to-implant contact than did UT miniscrews, after both 3 and 6 weeks (p < 0.05). Also, early deposition of densely mineralized bone around APH-treated miniscrews was observed, implying good bonding to the treated surface. CONCLUSIONS: APH treatment enhanced the bioactivity, and the biomechanical and bone regenerative properties of the Ti6Al4V alloy miniscrews. The enhanced initial stability afforded should be valuable in orthodontic applications.

Acteoside suppresses RANKL-mediated osteoclastogenesis by inhibiting c-Fos induction and NF-κB pathway and attenuating ROS production.

Numerous studies have reported that inflammatory cytokines are important mediators for osteoclastogenesis, thereby causing excessive bone resorption and osteoporosis. Acteoside, the main active compound of Rehmannia glutinosa, which is used widely in traditional Oriental medicine, has anti-inflammatory and antioxidant potentials. In this study, we found that acteoside markedly inhibited osteoclast differentiation and formation from bone marrow macrophages (BMMs) and RAW264.7 macrophages stimulated by the receptor activator of nuclear factor-kappaB (NF-κB) ligand (RANKL). Acteoside pretreatment also prevented bone resorption by mature osteoclasts in a dose-dependent manner. Acteoside (10 µM) attenuated RANKL-stimulated activation of p38 kinase, extracellular signal-regulated kinases, and c-Jun N-terminal kinase, and also suppressed NF-κB activation by inhibiting phosphorylation of the p65 subunit and the inhibitor κBα. In addition, RANKL-mediated increases in the expression of c-Fos and nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1) and in the production of tumor necrosis factor-α, interleukin (IL)-1ß, and IL-6 were apparently inhibited by acteoside pretreatment. Further, oral acteoside reduced ovariectomy-induced bone loss and inflammatory cytokine production to control levels. Our data suggest that acteoside inhibits osteoclast differentiation and maturation from osteoclastic precursors by suppressing RANKL-induced activation of mitogen-activated protein kinases and transcription factors such as NF-κB, c-Fos, and NFATc1. Collectively, these results suggest that acteoside may act as an anti-resorptive agent to reduce bone loss by blocking osteoclast activation.

X-ray radiation at low doses stimulates differentiation and mineralization of mouse calvarial osteoblasts.

Radiotherapy is considered to cause detrimental effects on bone tissue eventually increasing bone loss and fracture risk. However, there is a great controversy on the real effects of irradiation itself on osteoblasts, and the mechanisms by which irradiation affects osteoblast differentiation and mineralization are not completely understood. We explored how X-ray radiation influences differentiation and bone-specific gene expression in mouse calvarial osteoblasts. Irradiation at 2 Gy not only increased differentiation and mineralization of the cells, but also upregulated the expression of alkaline phosphatase, type I collagen, osteopontin, and osteocalcin at early stages of differentiation. However, irradiation at higher doses (>2 Gy) did not stimulate osteoblast differentiation, rather it suppressed DNA synthesis by the cells without a toxic effect. Additional experiments suggested that transforming growth factor-beta 1 and runt-transcription factor 2 play important roles in irradiation- stimulated bone differentiation by acting as upstream regulators of bone-specific markers.

Continuous presence of H2O2 induces mitochondrial-mediated, MAPK- and caspase-independent growth inhibition and cytotoxicity in human gingival fibroblasts.

The continuous generation of reactive oxygen species (ROS) is one of the most important events that occur during periodontal inflammation. Hydrogen peroxide (H(2)O(2)) is widely used in dental clinics. Many investigators have tried to elucidate the exact effect of H(2)O(2) on human gingival fibroblasts (HGFs). These studies have shown that H(2)O(2) induces growth inhibition and apoptosis in cells. However, the mechanisms involved in H(2)O(2)-induced cell death in HGFs are not completely understood. In this study, we examine how continuously generated H(2)O(2) affects the viability and proliferation of HGFs using glucose oxidase (GO). We also explored the mechanisms by which the continuous presence of H(2)O(2) induces cell death. GO treatment not only inhibited HGF growth and proliferation, but it also induced cell death in HGFs without typical apoptotic features such as nuclear DNA laddering. This GO-mediated cytotoxicity was proportional to the levels of intracellular ROS that were generated, rather than proportional to changes of cellular antioxidant activities. GO treatment also resulted in the loss of mitochondrial membrane potential and the relocation of mitochondrial apoptogenic factors. There was also an acute and severe depletion of cellular ATP levels. However, none of the pharmacological inhibitors specific for mitogen-activated protein kinases (MAPKs) or pancaspase prevented GO-induced cell death. Treatment with either catalase or acteoside significantly attenuated the GO-mediated cytotoxicity in the HGFs, thereby suggesting a protective effect of antioxidants against ROS-mediated gingival damage. Here we demonstrate that continuously generated H(2)O(2) not only inhibits the viability and proliferation of HGFs, but also causes pyknotic/necrotic cell death through mitochondrial stress-mediated, MAPK- and caspase-independent pathways.

Anti-inflammatory potential of Phaseolus calcaratus Roxburgh, a oriental medicine, on LPS-stimulated RAW 264.7 macrophages.

OBJECTIVES: The seed of Phaseolus calcaratus Roxburgh (PHCR) has traditionally been used as a herbal medicine, considered to have anti-inflammatory potential. Here we examined the ability of PHCR seed extract to inhibit inflammatory responses of macrophages to bacterial toxin and the mechanism involved. METHODS: In the present study, we prepared four fractions from an ethanol extract of PHCR seed and investigated their effects on the production of nitric oxide and cytokines, and the expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. KEY FINDINGS: The fractions inhibited LPS-induced nitric oxide production and cyclooxygenase-2 (COX-2) expression in the cells. The ethyl acetate fraction at 100 µg/ml almost completely suppressed NO production, iNOS and COX-2 expression, and TNF-α and IL-6 secretion in cells stimulated with LPS. The fraction also inhibited phosphorylation of extracellular signal-regulated kinase (ERK) and p38 in LPS-stimulated cells with the attendant suppression of IκBα nuclear translocation and nuclear factor (NF)-κB activation. Furthermore, PHCR seed extracts contained a large number of phenolic compounds having antioxidant potentials against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and hydroxyl radicals. We identified catechin-7-O-ß-D-glucopyranoside as one of the active compounds responsible for the biological activity of PHCR seed extract. CONCLUSIONS: These results suggest for the first time that ethanol extracts from PHCR seed have anti-inflammatory potential on LPS-stimulated macrophages through the down-regulation of ERK/p38- and NF-κB-mediated signalling pathways.