3,162 research outputs found
Akt1-Inhibitor of DNA binding2 is essential for growth cone formation and axon growth and promotes central nervous system axon regeneration.
Mechanistic studies of axon growth during development are beneficial to the search for neuron-intrinsic regulators of axon regeneration. Here, we discovered that, in the developing neuron from rat, Akt signaling regulates axon growth and growth cone formation through phosphorylation of serine 14 (S14) on Inhibitor of DNA binding 2 (Id2). This enhances Id2 protein stability by means of escape from proteasomal degradation, and steers its localization to the growth cone, where Id2 interacts with radixin that is critical for growth cone formation. Knockdown of Id2, or abrogation of Id2 phosphorylation at S14, greatly impairs axon growth and the architecture of growth cone. Intriguingly, reinstatement of Akt/Id2 signaling after injury in mouse hippocampal slices redeemed growth promoting ability, leading to obvious axon regeneration. Our results suggest that Akt/Id2 signaling is a key module for growth cone formation and axon growth, and its augmentation plays a potential role in CNS axonal regeneration
Fatal Biliary-Systemic Air Embolism during Endoscopic Retrograde Cholangiopancreatography: A Case with Multifocal Liver Abscesses and Choledochoduodenostomy
We report a rare case of a massive fatal embolism that occurred in the middle of endoscopic retrograde cholangiopancreatography (ERCP) and retrospectively examine the significant causes of the event. The patient was a 50-year old female with an uncertain history of previous abdominal surgery for multiple biliary stones 20 years prior. The patient presented with acute right upper quadrant pain. An abdominal computed tomographic (CT) scan revealed the presence of multiple stones in the common bile duct (CBD) and intra-hepatic duct (IHD) with biliary obstruction, multifocal liver abscesses, and air-biliarygram. Emergency ERCP showed a wide and straight opening of choledochoduodenostomy, which may have been created during a previous surgery, and multiple filling defects in the CBD. With the use of a forward endoscope, mud stones were extracted through the opening of the choledochoduodenostomy. Cardiac arrest suddenly developed during the procedure, and despite immediate resuscitation, the patient died due to a massive systemic air embolism. We reviewed previously reported fatal cases and accessed factors facilitating air embolisms in this case
Validation and Reliability of a Smartphone Application for the International Prostate Symptom Score Questionnaire: A Randomized Repeated Measures Crossover Study
Background: Smartphone-based assessment may be a useful diagnostic and monitoring tool for patients. There have been many attempts to create a smartphone diagnostic tool for clinical use in various medical fields but few have demonstrated scientific validity. Objective: The purpose of this study was to develop a smartphone application of the International Prostate Symptom Score (IPSS) and to demonstrate its validity and reliability. Methods: From June 2012 to May 2013, a total of 1581 male participants (>= 40 years old), with or without lower urinary tract symptoms (LUTS), visited our urology clinic via the health improvement center at Soonchunhyang University Hospital (Republic of Korea) and were enrolled in this study. A randomized repeated measures crossover design was employed using a smartphone application of the IPSS and the conventional paper form of the IPSS. Paired t test under a hypothesis of non-inferior trial was conducted. For the reliability test, the intraclass correlation coefficient (ICC) was measured. Results: The total score of the IPSS (P=.289) and each item of the IPSS (P=.157-1.000) showed no differences between the paper version and the smartphone version of the IPSS. The mild, moderate, and severe LUTS groups showed no differences between the two versions of the IPSS. A significant correlation was noted in the total group (ICC=.935, P<.001). The mild, moderate, and severe LUTS groups also showed significant correlations (ICC=.616,.549, and .548 respectively, all P<.001). There was selection bias in this study, as only participants who had smartphones could participate. Conclusions: The validity and reliability of the smartphone application version were comparable to the conventional paper version of the IPSS. The smartphone application of the IPSS could be an effective method for measuring lower urinary tract symptoms.X1144Ysciescopu
Effect of DPSS laser on the shear bond strength of orthodontic brackets
PurposeāTo test the bonding of orthodontic brackets to teeth using a diode-pumped solid state
(DPSS) laser.
MethodsāA total of 60 extracted human teeth were divided randomly into four groups: Group 1
(control) - the brackets were bonded to teeth using the quartz-tungsten-halogen (QTH) light (800
mW/cm2) for 40 seconds; Groups 2ā4 - the brackets were bonded to teeth using the DPSS laser
(500 mW/cm2) for 40 seconds, 20 seconds, and 10 seconds, respectively. The teeth were debonded
using shear force in a universal testing machine, and the amount of residual adhesive remaining on
each tooth was evaluated. Statistical analysis was carried out for the shear bond strength (SBS)
and Adhesive Remnant Index (ART).
ResultsāThe brackets bonded using the DPSS laser for 40 seconds showed the highest mean
SBS (13.1Ā±1.2 MPa) among the groups. Furthermore, the DPSS laser with 10 seconds light-curing
could achieve 83% of the mean SBS obtained using the QTH light for 40 seconds. The ARI scores
showed no differences among all four groups suggesting a similar failure mode
Effect of 457ānm Diode-Pumped Solid State Laser on the Polymerization Composite Resins: Microhardness, Cross-Link Density, and Polymerization Shrinkage
Objective: The purpose of the present study was to test the usefulness of 457 nm diode-pumped solid state (DPSS) laser as a light source to cure composite resins. Materials and methods: Five different composite resins were light cured using three different light-curing units (LCUs): a DPSS 457 nm laser (LAS), a light-emitting diode (LED), and quartz-tungsten-halogen (QTH) units. The light intensity of LAS was 560 mW/cm2, whereas LED and QTH LCUs was ā¼900 mW/cm2. The degree of polymerization was tested by evaluating microhardness, cross-link density, and polymerization shrinkage. Results: Before water immersion, the microhardness of laser-treated specimens ranged from 40.8 to 84.7 HV and from 31.7 to 79.0 HV on the top and bottom surfaces, respectively, and these values were 3.3ā23.2% and 2.9ā31.1% lower than the highest microhardness obtained using LED or QTH LCUs. Also, laser-treated specimens had lower top and bottom microhardnesses than the other LCUs treated specimens by 2.4ā19.4% and 1.4ā27.8%, respectively. After ethanol immersion for 24 h, the microhardness of laser-treated specimens ranged from 20.3 to 63.2 HV on top and bottom surfaces, but from 24.9 to 71.5 HV when specimens were cured using the other LCUs. Polymerization shrinkage was 9.8ā14.7 Ī¼m for laser-treated specimens, and these were significantly similar or lower (10.2ā16.0 Ī¼m) than those obtained using the other LCUs. Conclusions: The results may suggest that the 457 nm DPSS laser can be used as a light source for light-curing dental resin composites
Appropriateness of rabies post-exposure prophylaxis in pediatric patients visiting the emergency department due to animal bite
Purpose To study the appropriateness of rabies post-exposure prophylaxis (rPEP) for children with animal bite who visited the emergency department (ED). Methods The study enrolled children younger than 18 years with animal bite who visited the National Medical Center ED between January 2014 and October 2017. The childrenās electronic medical records were retrospectively reviewed. Data for analysis included age, sex, body parts bitten by animals, species of animals, regions where animal bites occurred, history of recent antibiotics therapy and tetanus vaccination, and justification by the 2017 Guidelines for Rabies Control in Korea and implementation of rPEP. In children who underwent unjustified rPEP or did not undergo justified one, we recorded their guardiansā opinion for or against rPEP. Results Of the 63 enrolled children, rPEP was justified for 38 children by the Korean guidelines. Of the 38 children, 35 actually underwent rPEP. Among the remaining 3 children, 2 did not undergo the prophylaxis as per the guardiansā requests. Among the 25 children whose rPEP was not justified, 8 underwent the prophylaxis. Of these 8 children, 7 did based on the guardiansā requests. Conclusion In this study, inappropriate rPEP was usually affected by the guardiansā requests, regardless of the criteria for such prophylaxis. Thus, their requests for or against rPEP should be discussed with emergency physicians who are aware of the relevant criteria to prevent occurrence of rabies or unnecessary use of medical resources
The efficacy of tenofovir-based therapy in patients showing suboptimal response to entecavir-adefovir combination therapy
Background/Aims: Before tenofovir (TDF) become available in South Korea, combination therapy with entecavir (ETV) and adefovir (ADV) was the most potent regimen for chronic hepatitis B (CHB) patients who fail to respond to rescue therapy for drug resistance. We analyzed the efficacy of ETV-ADV combination therapy and investigated the clinical and clonal results of TDF-based rescue therapy in CHB patients refractory to this combination. Methods: We retrospectively reviewed the medical records of CHB patients treated for up to 3 years with ETV-ADV combination therapy as a rescue therapy for drug resistance. In cases refractory to this combination, clinical and clonal analyses were performed for TDF-based rescue therapy. Results: The analysis was performed on 48 patients. Twelve patients achieved a virological response (VR) within 3 years. A VR was subsequently achieved in nine of the ten patients without a VR who switched to TDF monotherapy. A VR was also achieved in six of the seven patients who switched to lamivudine-TDF combination therapy, and in two of the two patients who switched to ETV-TDF combination therapy. In an in vitro susceptibility test, viral replication was detected with TDF monotherapy but not with ETV-TDF combination therapy. Conclusions: The efficacy of ETV-ADV combination therapy was insufficient in CHB patients who were refractory to rescue therapy. A more potent regimen such as ETV-TDF combination therapy may be considered in such refractory cases
- ā¦