202 research outputs found
Remineralization Property of an Orthodontic Primer Containing a Bioactive Glass with Silver and Zinc
White spot lesions (WSLs) are irreversible damages in orthodontic treatment due to excessive etching or demineralization by microorganisms. In this study, we conducted a mechanical and cell viability test to examine the antibacterial properties of 0.2% and 1% bioactive glass (BAG) and silver-doped and zinc-doped BAGs in a primer and evaluated their clinical applicability to prevent WSLs. The microhardness statistically significantly increased in the adhesive-containing BAG, while the other samples showed no statistically significant difference compared with the control group. The shear bond strength of all samples increased compared with that of the control group. The cell viability of the control and sample groups was similar within 24 h, but decreased slightly over 48 h. All samples showed antibacterial properties. Regarding remineralization property, the group containing 0.2% of the samples showed remineralization properties compared with the control group, but was not statistically significant; further, the group containing 1% of the samples showed a significant difference compared with the control group. Among them, the orthodontic bonding primer containing 1% silver-doped BAG showed the highest remineralization property. The new orthodontic bonding primer used in this study showed an antimicrobial effect, chemical remineralization effect, and WSL prevention as well as clinically applicable properties, both physically and biologically
UVB Induces HIF-1α-Dependent TSLP Expression via the JNK and ERK Pathways
Thymic stromal lymphopoietin (TSLP) may have a key role in the initiation and maintenance of allergic inflammatory diseases, including atopic dermatitis. The present study revealed that UVB radiation exposure could induce TSLP expression in human keratinocytes and a human skin equivalent model. In addition, we investigated the regulatory mechanism of UVB-induced TSLP expression in keratinocytes. TSLP expression was upregulated by transfection with pcDNA3âhypoxia-inducible factor (HIF)-1α (P402A and P564A), which stably expresses HIF-1α protein. UVB-induced TSLP induction in keratinocytes was suppressed in the treatment of mitogen-activated protein kinase inhibitors or small interfering RNAs against HIF-1α. The results of chromatin immunoprecipitation assays indicate the direct involvement of HIF-1α in UVB-mediated TSLP induction. Taken together, these findings indicate that UVB exposure may increase TSLP expression through a HIF-1α-dependent mechanism via the c-JUN N-terminal kinase and extracellular signal-regulated kinase pathways in human keratinocytes. Our data showed that UVB-induced TSLP might increase secretion of the T-helper type 2âattracting chemokine (câc motif) ligand 17 by human dendritic cells. The present study suggests an important role of HIF-1α in UVB-mediated immune response in keratinocytes
Safety and feasibility of hybrid tracheostomy
Background Percutaneous dilatational tracheostomy (PDT) is widely used in intensive care units, but this conventional method has some disadvantages, such as requirement of a lot of equipment and experts at the site. Especially, in situations where the patient is isolated due to an infectious disease, difficulties in using the equipment may occur, and the number of exposed persons may increase. In this paper, we introduce hybrid tracheostomy that combines the advantages of surgical tracheostomy and PDT and describe our experiences. Methods Data from 55 patients who received hybrid tracheostomy without bronchoscopy from January 2020 to February 2021 were collected and reviewed retrospectively. Hybrid tracheostomy was performed at the bedside by a single thoracic surgeon. The hybrid tracheostomy method was as follows: after the skin was incised and the trachea was exposed, only the extent of the endotracheal tube that could not be removed was withdrawn, and then tracheostomy was performed by the Seldinger method using a PDT kit. Results The average age was 66.5 years, and the proportion of men was 69.1%. Among the patients, 21.8% were taking antiplatelet drugs and 14.5% were taking anticoagulants. The average duration of the procedure was 13.3 minutes. There was no major bleeding, and there was one case of paratracheal placement of the tracheostomy tube. Conclusions In most patients, the procedure can be safely performed without any major complications. However, patients with a short neck, a neck burn or patients who have received radiation therapy to the neck should be treated with conventional methods
Protective Effects of Platycodon grandiflorum Aqueous Extract on Thioacetamide-induced Fulminant Hepatic Failure in Mice
The aim of the present study was to evaluate the protective activity of aqueous extract
from Platycodon grandiflorum (BC703) on thioacetamide (TA)-induced
hepatotoxicity in mice. We found that BC703 significantly decreased mortality and the
change in serum transaminase following TA administration. The group treated with BC703 at
doses of 1, 5, and 10â
mg/kg produced significant hepatoprotective effects against
TA-induced liver damage by decreasing the activities of serum enzymes, nitric oxide and
lipid peroxidation in dose-dependent manners. Histopathological studies further
substantiated the protective effect of BC703. These results show the hepatoprotective
activity of aqueous extract from Platycodon grandiflorum on
thioacetamide-induced fulminant hepatic failure
The Origin of Systematic Forecast Errors of Extreme 2020 East Asian Summer Monsoon Rainfall in GloSea5
This study examined the origin of the systematic underestimation of rainfall anomalies over East Asia during July-August 2020 in operational forecasts. Through partial nudging experiments, we found that the East Asian rainfall anomalies were successfully predicted in GloSea5 with corrected tropical sea surface temperature (SST) forcing. Once the observed SST is applied over the Indian Ocean and tropical central-eastern Pacific, a low-level anticyclonic anomaly over the subtropical western Pacific, which transports warm-moist air from the tropics to increase the East Asian precipitation, is well reproduced as observed. By further separating the SST into climatological and anomalous components, we revealed that the cold and dry mean state bias over the Indian Ocean and central-eastern Pacific is responsible for the weak anomalous atmospheric teleconnection patterns from the tropics to East Asia. This implies that correcting the model mean climatological fields can directly impact the operational seasonal forecast skill
Medium Access Control for Opportunistic Concurrent Transmissions under Shadowing Channels
We study the problem of how to alleviate the exposed terminal effect in multi-hop wireless networks in the presence of log-normal shadowing channels. Assuming node location information, we propose an extension of the IEEE 802.11 MAC protocol that sched-ules concurrent transmissions in the presence of log-normal shadowing, thus mitigating the exposed terminal problem and improving network throughput and delay performance. We observe considerable improvements in throughput and delay achieved over the IEEE 802.11 MAC under various network topologies and channel conditions in ns-2 simulations, which justify the importance of considering channel randomness in MAC protocol design for multi-hop wireless networks
A Case of Cerebral Gumma Presenting as Brain Tumor in a Human Immunodeficiency Virus (HIV)-Negative Patient
Syphilis, along with the recent increase of human immunodeficiency virus (HIV) patients, has also been on the rise. It has a broad spectrum of clinical manifestations, among which cerebral gumma is, a kind of neurosyphilis, however, it is rare and can be cured by penicillin. Thus, cerebral gumma needs to be differentially diagnosed from other brain masses that may be present in syphilis patients. We have experienced a case where the patient was first suspected of brain tumor, but confirmed by surgery to be cerebral gumma due to neurosyphilis. This is the first such case encountered in Korea, therefore, we report it here in. A 40-year old woman complaining of headaches was found to have a brain mass on her CT scans and MRI. Suspecting a brain Tumor, a resection was performed on the patient, and histological results revealed that the central portion of the mass contained necrotic material and the peripheral region was infiltrated with plasma cells. Warthin-Starry staining of the region revealed spirochetes, and the patient was thus diagnosed as brain gumma. Venereal Disease Research Laboratory (VDRL) of cerebrospinal fluid (CSF) was reactive. After an operation, penicillin-G at a daily dose of 24Ă106 U was given for 10 days from post-operative day 10, and thereafter, the mass disappeared
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