Global, Regional, and National Epidemiology of Alopecia Areata: A Systematic Review and Modelling Study.

BACKGROUND: Alopecia areata (AA) is a chronic autoimmune disease that leads to a high psychiatric, economic, and systemic disease burden. A comprehensive understanding of AA epidemiology is essential for evaluating healthcare source utilization; however, there is a lack of systematic approach for summarizing epidemiologic data on AA. OBJECTIVES: To systematically investigate the global, regional, and national incidence and prevalence of AA. METHODS: A structured search was conducted using the Ovid MEDLINE, EMBASE, Cochrane Library, Web of Science, SciELO, and Korean journal databases from their inception date to October 4, 2023. Studies that reported the prevalence or incidence of AA were included. We used a Bayesian hierarchical linear mixed model to analyse the prevalence estimates. The primary outcomes of our study were the global, regional, and national prevalence of physician-diagnosed AA for overall population, adults, and children. The incidence data were summarised descriptively. RESULTS: In total, 88 studies from 28 countries were included in the analysis. The reported incidence of alopecia areata tended to be higher in adults aged 19-50 years, and this trend was consistent with its estimated prevalence. The reported prevalence in overall population tended to be higher in men compared to in women. The estimated lifetime prevalence of AA was 0.10% (95% credible intervals, 0.03%-0.39%) in the general population worldwide, 0.12% (95% credible intervals, 0.02%-0.52%) in adults, and 0.03% (95% credible intervals, 0.01%-0.12%) in children. The estimated prevalence was highest in the Asian region and lowest in the African region. CONCLUSIONS: In this study, 48% of the total Global Burden of Disease regions had insufficient data reporting the prevalence or incidence of AA. Further studies are needed to provide epidemiological information on middle- and low-income countries. Our study can serve as a crucial reference in terms of healthcare policy decisions.

Comparing the diagnostic accuracy of PCR-reverse blot hybridization assay and conventional fungus study in superficial fungal infection of the skin: A systematic review.

BACKGROUND: In superficial fungal infections, prompt diagnosis and treatment are essential to prevent the spread of infection and minimise the impact on patients' quality of life. Traditional diagnostic methods, such as KOH smear and fungal culture, have limitations in terms of sensitivity and turnaround time. Recently, the PCR-reverse blot hybridization assay (PCR-REBA) has been developed for the direct detection of dermatophyte DNA. However, there is a lack of information assessing the diagnostic accuracy of PCR-REBA. OBJECTIVES: This systematic review aimed to evaluate the diagnostic accuracy of PCR-REBA in superficial fungal infections compared to conventional and molecular methods. METHODS: The comprehensive search containing Ovid MEDLINE and Embase databases was conducted on 7 August 2022. Two reviewers independently reviewed the included articles. Quality assessment was performed using the Newcastle-Ottawa Scale tool. RESULTS: The included studies were conducted in Korea (five studies) and the Netherlands (two studies), all of which were conducted in a single institution. The quality assessment of these studies indicated low risk of bias. When compared to the potassium hydroxide (KOH) smear and fungus culture, the sensitivity of PCR-REBA ranged from 85% to 100%, and the positive predictive values ranged from 58.9% to 100%. When compared to the RT-PCR, the sensitivity of PCR-REBA ranged from 93.3% to 100%, and the positive and negative predictive values were 91.6%-99.6% and 81.0%-89.1%, respectively. CONCLUSIONS: The PCR-REBA shows promise as a valuable diagnostic tool for dermatophytosis, offering practical and cost-effective benefits.

Highly efficient blue organic light-emitting diodes using quantum well-like multiple emissive layer structure.

In this study, the properties of blue organic light-emitting diodes (OLEDs), employing quantum well-like structure (QWS) that includes four different blue emissive materials of 4,4'-bis(2,2'-diphenylyinyl)-1,1'-biphenyl (DPVBi), 9,10-di(naphth-2-yl)anthracene (ADN), 2-(N,N-diphenyl-amino)-6-[4-(N,N-diphenyl amine)styryl]naphthalene (DPASN), and bis(2-methyl-8-quinolinolate)-4-(phenyl phenolato) aluminum (BAlq), were investigated. Conventional QWS blue OLEDs composed of multiple emissive layers and charge blocking layer with lower highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy level, and devices with triple emissive layers for more significant hole-electron recombination and a wider region for exciton generation were designed. The properties of triple emissive layered blue OLEDs with the structure of indium tin oxide (ITO) /N,N'-diphenyl-N,N'-bis(1-naphthyl-phenyl)-(1,1'-biphenyl)-4,4'-diamine (NPB) (700 Ǻ)/X (100 Ǻ)/BAlq (100 Ǻ)/X (100 Ǻ)/4,7-diphenyl-1,10-phenanthroline (Bphen) (300 Ǻ)/lithium quinolate (Liq) (20 Ǻ)/aluminum (Al) (1,200 Ǻ) (X = DPVBi, ADN, DPASN) were examined. HOMO-LUMO energy levels of DPVBi, ADN, DPASN, and BAlq are 2.8 to 5.9, 2.6 to 5.6, 2.3 to 5.2, and 2.9 to 5.9 eV, respectively. The OLEDs with DPASN/BAlq/DPASN QWS with maximum luminous efficiency of 5.32 cd/A was achieved at 3.5 V.

Effects of electron transport material on blue organ light-emitting diode with fluorescent dopant of BCzVBi.

High efficiency blue organic light emitting diodes (OLEDs), based on 2-me-thyl-9,10-di(2-naphthyl) anthracene (MADN) doped with 4,4'-bis(9-ethyl-3-carbazovinylene)-1,1'-biphenyl (BCzVBi), were fabricated using two different electron transport layers (ETLs) of tris(8-hydroxyquinolino)-aluminum (Alq3) and 4,7-di-phenyl-1,10-phenanthroline (Bphen). Bphen ETL layers favored the efficient hole-electron recombination in the emissive layer of the BCzVBi-doped blue OLEDs, leading to high luminous efficiency and quantum efficiency of 8.34 cd/A at 100 mA/cm2 and 5.73% at 100 cd/m2, respectively. Maximum luminance of blue OLED with Bphen ETL and Alq3 ETL were 10670 cd/m2, and CIExy coordinates of blue OLEDs were (0.180, 0279) and (0.155, 0.212) at 100 cd/m2.

High contrast blue organic light-emitting diodes using inorganic multilayers of Al and ZnSe.

High contrast blue organic light-emitting diodes were fabricated using an inorganic multilayer of NPB (700 Å)/MADN (200 Å)/Alq3 (300 Å)/LiF (10 Å)/Al (70 Å)/ZnSe (300 Å)/Al (1000 Å). The optical and electrical characteristics were measured and compared to conventional organic light-emitting devices (OLEDs) and OLEDs with polarizers. OLEDs with the metal multilayer cathodes had an improved contrast ratio of 135∶1 compared to 104∶1 for OLEDs with polarizers. In addition, the multilayer OLEDs had a low turn-on voltage of 3.5 V due to energy band fitting of ZnSe with Al and the electron transport layer.

Flexible top-emitting organic light-emitting diodes using semi-transparent multi-metal layers.

In this paper, the improved device performance of top-emitting organic light-emitting diodes (TEOLEDs) with a thin multi-metal layer stack of nickel/silver/nickel (Ni/Ag/Ni) and aluminum/silver/aluminum (Al/Ag/Al) that were used as the anode and cathode on a flexible substrate is discussed. In particular, Indium-Tin-Oxide (ITO) as an anode electrode has been used recently even though it has some problems for flexible devices. Therefore we suggested that a thin multi-metal layer electrode as a new anode is fabricated instead of ITO anode. It was verified that the ITO-free TEOLEDs showed an enhanced probability of the recombination of the electrons and holes through an improved electron/hole charge balance. We also analyzed the optical and electrical characteristics using the current density, luminance, luminance efficiency, external quantum efficiency (EQE), CIE x, y coordinates, and EL spectra of flexible TEOLED devices were characterized. ITO-free, flexible, green-emitting OLEDs with a low cost and a simple process were demonstrated.

Development of a novel quality assurance system based on rolled-up and rolled-out radiochromic films in volumetric modulated arc therapy.

PURPOSE: To develop a cylindrical phantom with rolled-up radiochromic films and dose analysis software in the rolled-out plane for quality assurance (QA) in volumetric modulated arc therapy (VMAT). METHODS: The phantom consists of an acrylic cylindrical body wrapped with radiochromic film inserted into an outer cylindrical shell of 5 cm thickness. The rolled-up films with high spatial resolution enable detection of specific dose errors along the arc trajectory of continuously irradiated and modulated beams in VMAT. The developed dose analysis software facilitates dosimetric evaluation in the rolled-up and rolled-out planes of the film; the calculated doses on the corresponding points where the rolled-up film was placed were reconstructed into a rectangular dose matrix equivalent to that of the rolled-out plane of the film. The VMAT QA system was implemented in 3 clinical cases of prostate, nasopharynx, and pelvic metastasis. Each calculated dose on the rolled-out plane was compared with measurement values by modified gamma evaluation. Detected positions of dose disagreement on the rolled-out plane were also distinguished in cylindrical coordinates. The frequency of error occurrence and error distribution were summarized in a histogram and in an axial view of rolled-up plane to intuitively identify the corresponding positions of detected errors according to the gantry angle. RESULTS: The dose matrix reconstructed from the developed VMAT QA system was used to verify the measured dose distribution along the arc trajectory. Dose discrepancies were detected on the rolled-out plane and visualized on the calculated dose matrix in cylindrical coordinates. The error histogram obtained by gamma evaluation enabled identification of the specific error frequency at each gantry angular position. The total dose error occurring on the cylindrical surface was in the range of 5%-8% for the 3 cases. CONCLUSIONS: The developed system provides a practical and reliable QA method to detect dosimetric errors according to the gantry angle. Film dosimetry based on rolled-up and rolled-out techniques leads to dose verification in the subspaces of the 3D dose volume. The system can be employed as an alternative tool to detect the pitfalls of planar dose verification.

Effect of ciprofloxacin/dexamethasone versus ciprofloxacin/hydrocortisone on lipopolysaccharide-induced experimental otitis media.

OBJECTIVES: The purpose of this study is to compare the effect of topical ciprofloxacin/dexamethasone versus topical ciprofloxacin/hydrocortisone on the outcome of lipopolysaccharide (LPS)­induced otitis media with effusion in chinchillas. STUDY DESIGN: A randomized experimental animal study. SETTING: Jerry L. Pettis Veteran's Medical Center. SUBJECTS AND METHODS: Otitis media with effusion was induced in 5 groups of chinchillas, 6 per group, by injecting 0.3 mL (1 mg/mL) of Salmonella enteric LPS into the superior bullae of each chinchilla with a venting needle in place. Each group was treated with 0.2 mL of test substance at ­2, 24, 48, and 72 hours relative to the 0-hour LPS induction. Group 1 was treated with vehicle control. Groups 2 to 5 received 0.3% ciprofloxacin with either 0.1% dexamethasone (group 2), 1% dexamethasone (group 3), 0.1% hydrocortisone (group 4), or 1% hydrocortisone (group 5). The outcome of each treatment was measured by the amount of middle ear effusion present and mucosal thickness at 120 hours posttreatment. RESULTS: Ciprofloxacin/dexamethasone 1% significantly (P = .0150) reduced middle ear effusion compared with control. Ciprofloxacin/dexamethasone 1% significantly reduced the mucosal thickness when compared with vehicle control (P = .0005), ciprofloxacin/dexamethasone 0.1% (P = .0240), and ciprofloxacin/hydrocortisone 0.1% (P = 1.00). Results also showed a dose-response effect between the ciprofloxacin/dexamethasone concentrations. CONCLUSIONS: This study demonstrated that treatment with a combination of topical ciprofloxacin and corticosteroid decreased the middle ear effusion when compared with the control group and that ciprofloxacin/dexamethasone suspension reduced the severity of LPS-induced experimental otitis media more than ciprofloxacin/hydrocortisone did.

Effect of topical glucocorticoid treatment in chinchilla model of lipopolysaccharide induced otitis media with effusion.

OBJECTIVE: To compare the efficacy of topical treatment with three glucocorticoids in lipopolysaccharide induced otitis media with effusion (OME). METHODS: Chinchillas were divided into seven treatment groups consisting of vehicle and three glucocorticoids: dexamethasone sodium phosphate (DSP), fluticasone propionate (FP), and hydrocortisone, each at concentrations of 0.1% and 1.0%. LPS (300 µg) was injected into the superior bullae of chinchillas to induce OME. Animals were treated with test substances at -2, 24, and 48 h relative to LPS inoculation. After 96 h, chinchillas were euthanized, samples of middle ear effusion (MEE) were collected, and temporal bones were removed for histopathological examination. Reduction of OME was evaluated by measuring MEE volume and thickness of mucosal lining for each bulla. RESULTS: One percent treatment of FP significantly reduced MEE. One percent treatment of DSP and HC significantly reduced the mucosal thickness (MT), DSP (15.0 µM) more than HC (30.8 µM). Treatment with 0.1% glucocorticoids did not lead to any significant reduction. CONCLUSIONS: Clearance of otitis media with effusion seems to be a class effect among glucocorticoids. DSP was the best in reducing MT. It is important to evaluate treatment with various glucocorticoids in order to discover alternative drugs for OME.

Application of a novel dose-uncertainty model for dose-uncertainty analysis in prostate intensity-modulated radiotherapy.

PURPOSE: To analyze dose uncertainty using a previously published dose-uncertainty model, and to assess potential dosimetric risks existing in prostate intensity-modulated radiotherapy (IMRT). METHODS AND MATERIALS: The dose-uncertainty model provides a three-dimensional (3D) dose-uncertainty distribution in a given confidence level. For 8 retrospectively selected patients, dose-uncertainty maps were constructed using the dose-uncertainty model at the 95% CL. In addition to uncertainties inherent to the radiation treatment planning system, four scenarios of spatial errors were considered: machine only (S1), S1 + intrafraction, S1 + interfraction, and S1 + both intrafraction and interfraction errors. To evaluate the potential risks of the IMRT plans, three dose-uncertainty-based plan evaluation tools were introduced: confidence-weighted dose-volume histogram, confidence-weighted dose distribution, and dose-uncertainty-volume histogram. RESULTS: Dose uncertainty caused by interfraction setup error was more significant than that of intrafraction motion error. The maximum dose uncertainty (95% confidence) of the clinical target volume (CTV) was smaller than 5% of the prescribed dose in all but two cases (13.9% and 10.2%). The dose uncertainty for 95% of the CTV volume ranged from 1.3% to 2.9% of the prescribed dose. CONCLUSIONS: The dose uncertainty in prostate IMRT could be evaluated using the dose-uncertainty model. Prostate IMRT plans satisfying the same plan objectives could generate a significantly different dose uncertainty because a complex interplay of many uncertainty sources. The uncertainty-based plan evaluation contributes to generating reliable and error-resistant treatment plans.

The characteristics of dental X-ray fluoroscopic equipment 'DreamRay 60F'.

This study examined the characteristics of the dental X-ray fluoroscopic equipment, 'DreamRay 60F', which was recently developed in Korea. The output linearity, output reproducibility, half-value layer (HVL), leakage radiation and scattered radiation were measured using an ionisation chamber. The surface dose equivalent rate and estimated dose equivalent of the operator were also calculated. The output linearity was 0.0015-0.0175 and the coefficient of variation for the output reproducibility was 0.0013-0.0074. The experimental HVL was 2.1 mm Al, and the leakage dose rate at 100 cm from the X-ray focus ranged from 2.70 to 19.66 microGy h (-1) depending on the direction. The scattered radiation doses differed significantly (1.7-16.8 times) depending on the distance and direction. If an operator is exposed for 10 min per procedure, 5 procedures a day at 5 days a week, he/she sitting at a 90 degrees direction will receive an annual dose equivalent of 13.0 mSv (at 30 cm) and 63.7 mSv (at 50 cm) in the trunk and face surface, respectively.

Glucocorticoids reduce nitric oxide concentration in middle ear effusion from lipopolysaccharide induced otitis media.

OBJECTIVE: Otitis media with effusion (OME) is a common childhood disease that is characterized by an accumulation of fluid in the middle ear. Chronic OME can also lead to sensorineural hearing loss (SNHL). Nitric oxide (NO), an inflammatory mediator (IM) of OME, is a free radical known to regulate cell proliferation, cell death, and angiogenesis. Previous studies have shown that nitric oxide may cause SNHL through outer hair cell (OHC) cytotoxicity. This experiment was designed to determine whether glucocorticoids, dexamethasone, fluticasone propionate, or rimexolone, can reduce the concentration of NO in middle ear effusion (MEE). METHODS: Fifty-three chinchillas were divided into 7 groups, vehicle vs. each glucocorticoid at 0.1% and 1.0% concentrations. Due to anesthesia complications, N ranged from 6 to 9 per group. Two hundred microlitres of each test article was injected into the bullae of each animal. Two hours later, lipopolysaccharide (LPS) (0.3mg in solution) was added. Test articles were re-administered at 24 and 48h post-LPS induction. After 96h, animals were euthanized and the MEE was collected. RESULTS: All three glucocorticoids numerically reduced NO concentration in the middle ear when administered at 0.1%, but only FP showed a significant reduction. At 1.0% concentrations, all 3 steroids significantly reduced NO concentration. CONCLUSION: This study suggests that glucocorticoid treatment reduces NO concentration in the MEE and may protect the ear from the SNHL caused by NO.

Medial or medio-lateral graft tympanoplasty for repair of tympanic membrane perforation.

OBJECTIVE: To describe and evaluate the medio-lateral graft tympanoplasty(1) for the reconstruction of anterior or subtotal tympanic membrane (TM) perforation and medial graft tympanoplasty for posterior TM perforation. METHODS: Retrospective study of 200 patients who underwent medio-lateral graft tympanoplasty (100 cases) and medial graft tympanoplasty (100 cases) at community and tertiary care medical centers from 1995 to 2006. All patients underwent preoperative and postoperative audiograms. In the medial graft tympanoplasty, the graft is placed entirely medial to the remaining TM and malleus. First, margin of TM perforation is denuded removing ring of squamous tissue. Tympanomeatal flap is elevated. Temporalis fascia is harvested, semidried, and grafted medial to the TM perforation and malleus with Gelfoam packing supporting the graft. In the medio-lateral graft technique, posterior tympanomeatal flap is elevated same as in the medial graft tympanoplasty first. Anterior-medial canal skin is elevated down to the annulus. At the annulus only squamous epithelial layer of TM is elevated up to anterior half of the TM perforation. Temporalis fascia is grafted medial to posterior half of the perforation and lateral to anterior half of the de-epithelialized TM perforation up to the annulus. Anterior canal skin is rotated to cover the fascia graft and TM perforation as a second layer closure. Patients were followed for at least six months. Outcome was considered successful if TM is healed and intact. RESULTS: There were four failures (96% success rate) in medial graft method for posterior TM perforation due to infection and re-perforation. In the medio-lateral graft tympanoplasty, there were three failures (97% success rate) due to a postoperative infection, anterior blunting and recurrent cholesteatoma. CONCLUSION: The medial graft tympanoplasty works well for posterior TM perforation. The medio-lateral graft method is an excellent method for the reconstruction of large anterior or subtotal TM perforation. This new method should help otologic surgeons to improve outcome of tympanoplasty for anterior or subtotal TM perforation.

High efficient white organic light-emitting diodes using BCzVBi as blue fluorescent dopant.

Efficiency improvement and color optimization of white organic light-emitting diodes (WOLEDs) were achieved via employing blue host DPVBi doped with blue fluorescent, BCzVBi. The structure of high efficient WOLED device was composed of ITO/NPB/DPVBi:BCzVBi-6%/MADN:DCM2-0.5%/Bphen/Liq/Al. WOLED doped by blue fluorescent BCzVBi exhibits 6.19 cd/A of luminous efficiency and 15400 cd/m2 of maximum luminescence. It also performs 480 cd/m2 of luminance at 5.7 V and 15400 cd/m2 at 12.9 V with CIE(x,y) coordinates of (0.33, 0.32) and (0.32, 0.32), respectively. Hole carrier and energy transfer from DPVBi to BCzVBi are proposed to explain the observed phenomena.

Improved imaging of the cervico-thoracic junction in computed tomography.

PURPOSE: To reduce beam hardening artifacts caused by the shoulder joint, we explored new and unique methods to improve the quality of images, such as varying the injection site and changing the position of patients (swimmers position). MATERIALS AND METHODS: Fifth-four patients underwent neck CT examinations performed in routine and swimmers position and with a 64-slice MDCT scanner in spiral scanning. To examine the difference due to the injection sites of contrast material, subjects were divided into right- and left-side groups. For the evaluation of images, we carried out a subjective and objective assessment based on radiologists' ratings and noise measurement. RESULTS: Images of the lower neck in the swimmers position exhibited less hardening and streak artifacts. The subjective and objective evaluations showed that the swimmers position received higher rating by radiologists and had lower noise level than that of routine position. The swimmers position was the most effective for the diagnosis of the cervico-thoracic junction area. As for the injection site, we obtained better images by an injection of contrast material in the right arm than in the left. CONCLUSION: CT examination of the lower neck in the swimmers position may improve the quality of image and the effectiveness of diagnosis. The injection of a contrast material to the right side rather than the left side reduced foreign body artifacts.

Patient dose measurements in diagnostic radiology procedures in Korea.

This study is the first nationwide investigation aimed at estimating the patient dose for radiographic examinations in Korea including gastrointestinal studies, computed tomography and mammography. The survey data from 161 hospitals and the dose data from 32 hospitals were analysed. The third quartile entrance surface dose, dose area product (DAP), weighted CT dose index (CTDIw) and mean glandular dose (MGD) were reported. All the estimated doses were less than the stated International Atomic Energy Agency (IAEA) reference levels for radiographic examinations. However, DAPs for the fluoroscopic examinations had higher dose values than the IAEA reference levels. In addition, the CTDIw and MGD were lower than the IAEA reference levels.

Storage of multiple holograms of equal diffraction efficiency in a phase-code multiplexing system.

Computer simulations of 8-, 32-, and 128-bit phase-code multiplexing systems are presented, and exposure schedules are obtained numerically for equal diffraction efficiency. An analytic prediction of the exposure schedule is derived as a double exponential function that can be applied to the three different systems for variation of diffraction efficiency of less than +/- 13.5%. Eight holograms were experimentally recorded in a BaTiO3 crystal according to our exposure schedule and also to conventional schedules, which had originally been derived for an angle-multiplexing system. It is shown that the experimental data agree well with the computer simulations.