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1.
Chemistry ; : e202401280, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38739534

ABSTRACT

4- and 5-coordinate zinc thiolate complexes supported either by bis(carboxamide)pyridine frameworks or by substituted tris(pyrazolyl)borate ligands react with elemental sulfur (S8) following two distinct pathways. Some zinc thiolate moieties insert sulfur atoms to form zinc polysulfanide complexes, while others reduce sulfur and oxidize the thiolate. Here, we compare the effects of ligand electronics, strain, and sterics for selecting the respective reaction pathway. These results show that chelating and electron-deficient thiolate ligands better stabilize persistent zinc-bound polysulfanide species.

2.
Chem Sci ; 15(19): 7332-7341, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38756819

ABSTRACT

Sulfur-containing anions (e.g. thiolates, polysulfides) readily exchange in solution, making control over their solution speciation and distribution challenging. Here, we demonstrate that different redox-inactive alkali, alkaline earth, and transition metals (Li+, Na+, K+, Mg2+, Ca2+, Zn2+, and Cd2+) shift the equilibria of sulfur catenation or sulfur reduction/oxidation between thiolate, polysulfanide, and polysulfide anions in acetonitrile solution. The thermodynamic factors that govern these equilibria are examined by identification of intermediate metal thiolate and metal polysulfide species using a combination of NMR spectroscopy, electronic absorption spectroscopy, and mass spectrometry. Electrochemical measurements demonstrate that the metal cation of the electrolyte modulates both sulfur reduction and thiolate oxidation potentials. DFT calculations suggest that the changes in equilibria are driven by stronger covalent interactions between polysulfide anions and more highly charged cations.

3.
J Am Chem Soc ; 144(45): 20630-20640, 2022 11 16.
Article in English | MEDLINE | ID: mdl-36326496

ABSTRACT

A zinc dithiolate complex supported by a [N3S2] ligand was studied as a model for zinc-mediated thiolate-disulfide exchange, enabling isolation of a zinc-bound mixed-disulfide intermediate. Solution-phase characterization of this zinc-disulfide complex indicates an interaction between the zinc center and the disulfide moiety that results in activation of the S-S bond for subsequent reactions. Comparison of this reaction with disulfide exchange by a previously prepared zinc tetrasulfanido complex demonstrates that sulfane sulfur (S0) acts as an efficient thiolate trapping agent, that is, polysulfanide anions are much less basic than thiolates. The resulting polysulfanide anions also exhibit decreased nucleophilicity compared to the parent thiolate anions. Alkylation kinetics comparisons between the zinc dithiolate and zinc tetrasulfanido complexes indicate attenuation of zinc-bound thiolate nucleophilicity by sulfane. These results suggest a general interplay between zinc, sulfane, and thiol/thiolate reactivity that can significantly impact biological redox processes.


Subject(s)
Sulfur , Zinc , Zinc/chemistry , Sulfur/chemistry , Sulfhydryl Compounds/chemistry , Disulfides
4.
Br J Surg ; 107(6): 712-719, 2020 05.
Article in English | MEDLINE | ID: mdl-32031248

ABSTRACT

BACKGROUND: Indocyanine green (ICG) fluorescence lymphography can be used to visualize the lymphatic drainage of gastric cancer. Few studies have been performed to identify lymphatic drainage patterns after endoscopic submucosal dissection (ESD). ESD results in changes to lymphatics owing to fibrosis of the submucosal layer. This study aimed to evaluate the efficacy of ICG fluorescence lymphography for visualization of lymphatic drainage after ESD, and to assess its clinical application in additional gastrectomy after ESD for early gastric cancer. METHODS: All patients who underwent gastrectomy after ESD between 2014 and 2017 in a single centre were reviewed. ICG was injected endoscopically into the submucosal layer around the ESD scar the day before surgery. At the time of surgery, lymph nodes (LNs) were visualized and lymphadenectomy was performed with near-infrared imaging. Ex vivo, all LNs were examined for the presence of fluorescence. Number of LNs resected and number of tumour-positive LNs were compared between patients who underwent near-infrared imaging and those who had conventional lymphadenectomy without intraoperative imaging. RESULTS: Some 290 patients underwent gastrectomy after ESD, 98 with fluorescence lymphography-guided lymphadenectomy and 192 with conventional lymphadenectomy. Fluorescence lymphography visualized lymphatic drainage in all patients, without complications related to ICG injection or near-infrared imaging. Fluorescence lymphography visualized all stations containing metastatic LNs. The sensitivity for detecting LN metastasis in fluorescent stations was 100 per cent (9 of 9 stations), and the negative predictive value was 100 per cent (209 of 209). One patient with LN metastasis had one non-fluorescent metastatic LN within a fluorescent station. CONCLUSION: Fluorescence lymphography successfully visualized all draining LNs after ESD, with high sensitivity and negative predictive value for detecting LN metastasis. Fluorescence lymphography-guided lymphadenectomy could be an alternative to systematic lymphadenectomy during additional surgery after ESD.


ANTECEDENTES: La linfografía de fluorescencia con verde de indocianina (indocyanine green, ICG) visualiza el drenaje linfático del cáncer gástrico. Se han realizado pocos estudios para identificar los patrones de drenaje linfático tras una disección submucosa endoscópica (endoscopic submucosal dissection, ESD). La ESD introduce cambios de los linfáticos debido a la fibrosis de la capa submucosa. El objetivo de este estudio era valorar la eficacia de la linfografía con ICG para visualizar el drenaje linfático tras ESD y evaluar su aplicación clínica en la gastrectomía adicional después de ESD por carcinoma precoz gástrico (early gastric cancer, EGC). MÉTODOS: Se revisaron todos los pacientes sometidos a gastrectomía tras ESD entre 2014 y 2017 en un único centro. El ICG se inyectó por vía endoscópica en la capa submucosa alrededor de la cicatriz tras ESD el día antes de la cirugía. En el momento de la cirugía, se visualizaron los ganglios linfáticos (lymph nodes, LNs) y se realizó la linfadenectomía siguiendo las imágenes de infrarrojo. Ex vivo, todos los LNs se examinaron para detectar la presencia de fluorescencia. Se compararon el número de LNs resecados y el número de LNs afectados por el tumor entre pacientes sometidos a imágenes de infrarrojo y pacientes a los que se les realizó una linfadenectomía convencional sin imágenes intraoperatorias. RESULTADOS: Un total de 290 pacientes fueron sometidos a gastrectomía tras ESD (98 con linfadenectomía por linfografía con ICG y 192 con linfadenectomía convencional). La linfografía con ICG visualizó el drenaje linfático en todos los pacientes, sin complicaciones relacionadas con la inyección de ICG o con las imágenes de infrarrojo. La linfografía con ICG permitió visualizar todas las estaciones ganglionares en las que había LNs metastásicos. La sensibilidad para detectar los LN con metástasis en las estaciones con fluorescencia fue del 100% (9 de 9 estaciones), y el valor predictivo negativo (negative predictive value, NPV) del 100% (209 de 209 estaciones). Un paciente con metástasis en LN tenía un ganglio metastásico sin fluorescencia en el seno de una estación con fluorescencia. CONCLUSIÓN: La linfografía con fluorescencia visualiza satisfactoriamente todos los LNs que drenan después de ESD, con una elevada sensibilidad y NPV para detectar metástasis en LN. La linfadenectomía guiada por fluorescencia podría ser una alternativa a la linfadenectomía convencional durante la cirugía adicional después de ESD.


Subject(s)
Endoscopic Mucosal Resection , Gastrectomy , Intraoperative Care/methods , Lymph Nodes/diagnostic imaging , Lymphography/methods , Optical Imaging/methods , Stomach Neoplasms/surgery , Adult , Aged , Female , Fluorescent Dyes , Humans , Indocyanine Green , Lymph Node Excision , Lymph Nodes/pathology , Lymph Nodes/surgery , Lymphatic Metastasis , Male , Middle Aged , Neoplasm Staging , Predictive Value of Tests , Reoperation , Retrospective Studies , Sensitivity and Specificity , Stomach Neoplasms/diagnostic imaging , Stomach Neoplasms/pathology
5.
Eur J Neurol ; 27(5): 900-902, 2020 05.
Article in English | MEDLINE | ID: mdl-32064742

ABSTRACT

BACKGROUND AND PURPOSE: We analyzed the incidence and causes of oral anticoagulant (OAC) cessation and subsequent stroke after OAC withdrawal in a cohort of Korean stroke patients with atrial fibrillation. METHODS: The Korean Atrial Fibrillation Evaluation Registry in Ischemic Stroke patients (K-ATTENTION) is a multicenter cohort study, merging stroke registries from 11 tertiary centers in Korea. The number of OAC interruption episodes and the reasons were reviewed from hospital records. Stroke after OAC withdrawal was defined when a patient experienced ischaemic stroke within 31 days after OAC withdrawal. Clinical variables were compared between patients who experienced stroke recurrence during OAC interruption and those who did not experience recurrence. RESULTS: Among 3213 stroke patients with atrial fibrillation, a total of 329 episodes of OAC interruption were detected in 229 patients after index stroke (mean age 72.9 ± 8.3 years, 113 female patients). The most frequent reason for OAC withdrawal was poor compliance [103 episodes (31.3%)] followed by extracranial bleeding [96 episodes (29.2%)]. Stroke after OAC withdrawal was noted in 13 patients. Mean age, vascular risk factor profile and mean CHA2 DS2 -VASc score were not significantly different between patients with and without recurrent stroke. CONCLUSIONS: A considerable number of stroke patients with atrial fibrillation experienced temporary interruption of OAC after index stroke, which was associated with stroke recurrence of 4.0 cases per 100 interruption episodes.


Subject(s)
Atrial Fibrillation , Brain Ischemia , Stroke , Administration, Oral , Aged , Aged, 80 and over , Anticoagulants/therapeutic use , Atrial Fibrillation/complications , Atrial Fibrillation/drug therapy , Atrial Fibrillation/epidemiology , Brain Ischemia/complications , Brain Ischemia/drug therapy , Brain Ischemia/epidemiology , Cohort Studies , Female , Humans , Incidence , Male , Middle Aged , Registries , Republic of Korea/epidemiology , Risk Assessment , Risk Factors , Stroke/complications , Stroke/drug therapy , Stroke/epidemiology
6.
Sci Rep ; 8(1): 4851, 2018 Mar 19.
Article in English | MEDLINE | ID: mdl-29555981

ABSTRACT

We propose the unique structure of highly dispersible single-walled carbon nanotubes (SWCNTs) in various solvents and polymers using the ZnO nano particle template. Buckled nanospring-shaped carbon nanotubes (NS-CNTs) were synthesized by a chemical reaction of ZnO nanoparticles with acid-treated SWCNTs and then dissolving ZnO through chemical etching. The unique structure of distorted hexagonal NS-CNTs encircled around ZnO nanoparticles was formed by the bending of SWCNTs caused by the agglomeration of chemically adsorbed Zn(OH)2, which is further crystallized as the polycrystalline ZnO inner core. The highly dispersible NS-CNTs could be incorporated in the poly[(vinylidenefluoride-co-trifluoroethylene] [P(VDF-TrFE)] copolymer, one of widely studied ferro- and piezo-electric polymer, up to the value of 15 wt% as nanofillers. The relative dielectric constant (K) of polymer nanocomposite, at 1 kHz, was greatly enhanced from 12.7 to the value of 62.5 at 11 wt% of NS-CNTs, corresponding to a 492% increase compared to that of pristine P(VDF-TrFE) with only a small dielectric loss tangent (D) of 0.1.

7.
Open Respir Med J ; 10: 36-45, 2016.
Article in English | MEDLINE | ID: mdl-27499820

ABSTRACT

INTRODUCTION: Pranlukast is a leukotriene receptor antagonist (LTRA) that is used as an additional controller of mild to moderate asthma. This study compared the efficacy and side effects of two bioequivalent preparations of pranlukast: original pranlukast (Onon(®); Ono Pharmaceutical, Japan) and a modified formulation of pranlukast (Prakanon(®); Yuhan Co, Korea) in patients with mild to moderate asthma. METHODS: Of the 34 subjects screened, 30 patients who were using standard medication to control asthma and scored less than 20 points on the Asthma Control Test(™) (ACT) were assigned randomly to one of the two groups in a prospective, open label, crossover study: group 1 received Prakanon(®) (150 mg/day) and group 2 received Onon(®) (450 mg/day) for 8 weeks each; after a 1-week rest period, the groups were switched to the alternative medication for further 8 weeks and monitored for 2 more weeks without study medication. Evaluation parameters included the ACT, quality of life questionnaire adult Korean asthmatics (QLQAKA), pulmonary function tests, peripheral blood tests, vital signs, and adverse events. RESULTS: Thirty patients were enrolled and 21 completed the trial: 10 in group 1 and 11 in group 2. The baseline data of the two groups did not differ. No statistical significant differences were observed in efficacy and lung function at each time and in changes from baseline value between the two kinds of pranlukast. The final asthma control rate was 81% with Prakanon(®) and 76% with Onon(®). There were no differences in vital signs and laboratory data at each time and in changes from baseline value between the two drugs. There were no differences in adverse events between the two drugs. The most common side effect was abdominal pain. Drug compliance was high, without differences between the two drugs. CONCLUSION: These findings suggest that Prakanon(®) which is an improved formulation of pranlukast at a lower dose than the original formulation, Onon(®), has a similar efficacy and side effect profile in the control of persistent asthma.

8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 303-306, 2016 Aug.
Article in English | MEDLINE | ID: mdl-28268337

ABSTRACT

This paper reports a low-cost solution to the early detection of urinary nitrite, a common surrogate for urinary tract infection (UTI). We present a facile method to fabricate a disposable and flexible colorimetric [1] nitrite sensor and its urine-activated power source [2] on a hydrophobic (wax) paper through laser-assisted patterning and lamination. Such device, integrated with interface circuitry and a Bluetooth low energy (BLE) module can be embedded onto a diaper, and transmit semi-quantitative UTI monitoring information in a point-of-care and autonomous fashion. The proposed nitrite sensing platform achieves a sensitivity of 1.35 ms/(mg/L) and a detection limit of 4 mg/L.


Subject(s)
Absorbent Pads , Biosensing Techniques/methods , Electric Power Supplies , Mass Screening , Nitrites/analysis , Urinalysis/methods , Urinary Tract Infections/diagnosis , Urinary Tract Infections/urine , Calibration , Colorimetry , Electricity , Humans , Point-of-Care Systems
9.
Oncogene ; 34(34): 4500-8, 2015 Aug 20.
Article in English | MEDLINE | ID: mdl-25417701

ABSTRACT

Deleted in Breast Cancer 1 (DBC1), a negative regulator of deacetylase SIRT1, has been shown to act as an estrogen receptor α (ER) coactivator that has a key role in ER transcription complex assembly and estrogen-dependent breast cancer cell proliferation. However, little is known about its physiological role and mechanism of action in ER-negative breast cancer cells. Here we report that DBC1 functions as a coactivator for the oncogenic ETS transcription factor PEA3 to promote ER-negative breast cancer progression. DBC1 is required for the expression of PEA3 target genes and for recruitment of PEA3 and RNA polymerase II to PEA3 target promoters. We also demonstrated that acetylation of PEA3 stimulates its DNA binding and association with DBC1 by disrupting the intramolecular interaction of PEA3. The molecular mechanism underlying DBC1 function in PEA3-mediated transcription involves inhibition of SIRT1 interaction with PEA3 and of SIRT1-mediated deacetylation of PEA3. Moreover, DBC1 depletion inhibited the tumorigenic properties of ER-negative breast cancer cells in vitro and in vivo. Importantly, increased DBC1 expression correlated with shorter relapse-free survival of ER-negative breast cancer patients. Our results firmly established DBC1 as a critical coactivator of PEA3 and as a key player in PEA3-mediated breast cancer progression.


Subject(s)
Adaptor Proteins, Signal Transducing/physiology , Adenovirus E1A Proteins/physiology , Breast Neoplasms/etiology , Proto-Oncogene Proteins/physiology , Receptors, Estrogen/analysis , Acetylation , Adaptor Proteins, Signal Transducing/chemistry , Binding Sites , Breast Neoplasms/chemistry , Cell Line, Tumor , Disease Progression , Female , Humans , Protein Conformation , Proto-Oncogene Proteins c-ets , Sirtuin 1/physiology
10.
Ocul Immunol Inflamm ; 23(5): 362-70, 2015.
Article in English | MEDLINE | ID: mdl-24724869

ABSTRACT

PURPOSE: Identification of optimal enrollment criteria for a CMVR screening program suitable for a resource-limited environment. METHODS: A prospective audit was performed on newly diagnosed HIV patients referred for CMVR screening with any of the following four criteria: (1) visual symptoms, (2) low CD4(+) counts (<50 cells/µL), (3) AIDS-defining illnesses (ADI), and/or (4) opportunistic infections (OI). Odds ratios for each of the demographic factors and enrollment criteria were calculated. Sensitivities, specificities, and workload reduction for the various combinations were determined. RESULTS: A total of 348 screening visits for 176 HIV patients were performed. While individually only ADI was statistically significant for increased CMVR risk, the combination of CD4(+) counts <50 cells/µL with either ADI or visual symptoms or all 3 criteria were also statistically significant. Two enrollment criteria, ADI and ADI with CD4(+) <50 cells/µL, demonstrated good sensitivities, specificities, and workload reduction. CONCLUSION: We propose ADI and possibly CD4(+) counts <50 cells/µL as enrollment criteria for CMVR screening.


Subject(s)
Clinical Audit/methods , Cytomegalovirus Retinitis/diagnosis , HIV Infections/diagnosis , HIV , Mass Screening/methods , Adult , Cytomegalovirus Retinitis/complications , Cytomegalovirus Retinitis/epidemiology , Female , Follow-Up Studies , HIV Infections/complications , HIV Infections/epidemiology , Humans , Male , Morbidity/trends , Prospective Studies , Singapore/epidemiology
11.
AJNR Am J Neuroradiol ; 35(1): 113-8, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23828108

ABSTRACT

BACKGROUND AND PURPOSE: Alterations in the central autonomic network are hypothesized to play a role in the pathophysiologic mechanism underlying neurocardiogenic syncope; however, few data are available regarding the structural changes of the brain in this condition. We used voxel-based morphometry and regional volumetry to identify possible neuroanatomic correlates. MATERIALS AND METHODS: We prospectively studied 32 patients with neurocardiogenic syncope with a positive response to the head-up tilt test and 32 controls who had no history of syncope. We used voxel-based morphometry to compare GM volumes between patients and controls. In addition, regional volumes of structures known to be included in the central autonomic network were measured and compared between the groups. Correlation analyses were also performed between clinical variables and anatomic data. RESULTS: Voxel-based morphometry showed a significant GM volume reduction in the right insular cortex in patients with neurocardiogenic syncope compared with controls (corrected P = .033). Regional volumetry showed a significant reduction of right insular volumes in patients compared with controls (P = .002, MANCOVA). Smaller right insular volumes in patients with neurocardiogenic syncope were related to larger drops in systolic (P = .020) and diastolic (P = .003) blood pressures during the head-up tilt test. CONCLUSIONS: We observed a novel finding of right insular atrophy in patients with neurocardiogenic syncope with a positive response to the head-up tilt test, implicating the role of right insular dysfunction in the pathophysiologic mechanism underlying neurocardiogenic syncope. Our findings further support the hypothesis that right insular dysfunction may cause a decrease in sympathetic activity and a reciprocal increase in parasympathetic activity, leading to syncope.


Subject(s)
Cerebral Cortex/pathology , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Magnetic Resonance Imaging/methods , Neurons/pathology , Syncope, Vasovagal/pathology , Adolescent , Adult , Atrophy/pathology , Child , Female , Humans , Male , Reproducibility of Results , Sensitivity and Specificity , Young Adult
12.
Telemed J E Health ; 19(8): 627-31, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23756239

ABSTRACT

BACKGROUND: Screening for cytomegalovirus retinitis (CMVR) is important in patients with acquired immune deficiency syndrome and low CD4(+) counts. However, many human immunodeficiency virus (HIV) patients lack access to specialist ophthalmological care. Telemedicine screening is a cost-effective method for screening these patients. We aimed to report the use of composite nine-field digital fundus photography (DFP) images for CMVR screening. We report its sensitivity and specificity in detecting CMVR and the level of agreement with gold-standard binocular indirect ophthalmoscopy. MATERIALS AND METHODS: An audit was performed on our national CMVR screening program that screened all HIV patients referred to the Ophthalmology Department at Tan Tock Seng Hospital, Singapore. All patients underwent retinal screening with DFP. Images were categorized as CMVR-positive, CMVR-negative, suspicious, or unreadable by blinded retinal specialists. Patients subsequently underwent dilated gold-standard indirect ophthalmoscopy by a different retinal specialist. Diagnoses were categorized as CMVR-positive, CMVR-negative, or unreadable. Sensitivity and specificity of retinal findings on DFP and kappa values for level of agreement between the two screening methods were calculated. RESULTS: Three hundred seventy screenings on 188 patients were performed. Twenty-three eyes diagnosed with CMVR on indirect ophthalmoscopy were also identified on DFP (100% sensitivity). A 99.9% specificity was achieved. The fundus photograph of one eye without CMVR was read as CMVR-positive because of an artifact, accounting for a false-positive. Kappa values ranged from 0.739 to 0.987. CONCLUSIONS: DFP is a sensitive and specific method of screening HIV patients for CMVR and has a high level of agreement with indirect ophthalmoscopy.


Subject(s)
Cytomegalovirus Retinitis/diagnosis , Photography/methods , Telemedicine , Adult , Female , HIV Infections/complications , Humans , Male , Medical Audit , Middle Aged , Ophthalmoscopy/methods , Sensitivity and Specificity , Singapore
13.
J Nanosci Nanotechnol ; 13(1): 405-8, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23646746

ABSTRACT

The solution combustion process is used to synthesize Fe1.9925P0.0075O3 nano-powders. The sintered Fe1.9925P0.0075O3 bodies are alpha-Fe2O3-based single phase with the rhombohedral structure. The electrical conductivity increases with an increase in sintering temperature because of an increase in grain size and density. The absolute value of the Seebeck coefficient escalates with an increase in sintering temperature up to 1000 degrees C, and then decreases with a further rise in its sintering temperature. The Fe1.9925P0.0075O3 sintered at 1000 degrees C shows the highest power factor, i.e., 1.39 x 10(-5) W m(-1) K(-2) at 700 degrees C.


Subject(s)
Crystallization/methods , Ferric Compounds/chemistry , Metal Nanoparticles/chemistry , Metal Nanoparticles/ultrastructure , Electromagnetic Fields , Hot Temperature , Materials Testing , Particle Size , Thermal Conductivity
14.
Oncogene ; 32(35): 4160-8, 2013 Aug 29.
Article in English | MEDLINE | ID: mdl-22986521

ABSTRACT

Estrogen receptor α (ERα) has critical roles in the development and progression of breast cancer, and the coiled-coil co-activator (CoCoA) is an important ERα co-activator for estrogen-induced gene expression. The small ubiquitin-like modifier (SUMO) pathway is hyperactivated in breast cancer, but the mechanism by which SUMOylation regulates ERα-mediated transcription remains poorly understood. Here, we identified ZFP282 as a CoCoA-binding protein. ZFP282 associates directly with ERα and cooperates synergistically with CoCoA to enhance ERα function. ZFP282 is required for estrogen-induced expression of ERα target genes and estrogen-dependent breast cancer cell growth and tumorigenesis. In addition, we found that ZFP282 is SUMOylated and that SUMOylation positively regulates the co-activator activity of ZFP282 by increasing its binding affinity to ERα and CoCoA, and consequently increasing recruitment of ZFP282-CoCoA complex to the promoter of ERα target genes. These findings reveal essential roles for ZFP282 and its SUMOylation in estrogen signaling and breast tumorigenesis.


Subject(s)
Breast Neoplasms/etiology , Estrogen Receptor alpha/physiology , Signal Transduction/physiology , Sumoylation , Zinc Fingers , Cell Proliferation , Cell Transformation, Neoplastic , Female , Human T-lymphotropic virus 1/genetics , Humans , Terminal Repeat Sequences , Transcription, Genetic
15.
J Periodontal Res ; 48(4): 500-6, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23199371

ABSTRACT

BACKGROUND AND OBJECTIVE: Periodontitis is becoming a highly prevalent disease worldwide. Obstructive sleep apnea (OSA) is a common disorder that is characterized by repeated disruptions in breathing during sleep, and mouth breathing is a common characteristic among patients with OSA. We aimed to assess the hypothesis that OSA is associated with the onset and progression of periodontal disease. MATERIAL AND METHODS: This is a cross-sectional study of a total of 687 participants (460 men and 227 women), 47-77 years of age, who were examined between August 2009 and September 2010 as part of the Korean Genome and Epidemiology Study. The participants underwent standard polysomnography, clinical periodontal examination and health-screening examinations. Periodontitis was defined as clinical attachment level (CAL) ≥ 6 mm and probing pocket depth ≥ 4 mm. OSA was determined using the apnea-hypopnea index (AHI), and an AHI score of ≥ 5 was the cut-off used to indicate the presence of OSA. RESULTS: The results showed that 17.5% of the participants had periodontitis, 46.6% had OSA and 60.0% who were diagnosed with periodontitis had OSA. In our study, old age, male gender, current smoking status, mouth breathing during sleep and high AHI were identified as risk factors for periodontitis. OSA was positively associated with periodontitis [odds ratio (OR) = 1.84, 95% confidence interval (CI) = 1.18-2.87], probing pocket depth (OR = 2.22, 95% CI = 1.30-3.77) and CAL (OR = 1.86, 95% CI = 1.07-3.21) in a dose-response manner. Additionally, OSA was positively associated with periodontitis (OR = 2.51, 95% CI = 1.37-4.62) in subjects ≥ 55 years of age, but not in subjects < 55 years of age. CONCLUSION: There is a significant association between OSA and periodontal disease. Further research is needed to clarify the causal relationship between the two conditions.


Subject(s)
Periodontitis/epidemiology , Sleep Apnea, Obstructive/epidemiology , Age Factors , Aged , Cohort Studies , Cross-Sectional Studies , Disease Progression , Female , Humans , Male , Middle Aged , Mouth Breathing/epidemiology , Periodontal Attachment Loss/epidemiology , Periodontal Pocket/epidemiology , Polysomnography , Population Surveillance , Prospective Studies , Republic of Korea/epidemiology , Risk Factors , Sex Factors , Smoking
16.
Dermatol Surg ; 38(11): 1816-22, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22882208

ABSTRACT

BACKGROUND: Microneedle treatment is currently used in the cosmetic industry for several skin conditions. Despite their extensive use, there is lack of sufficient data on the safety of microneedles. OBJECTIVE: To investigate the degree of acute skin damage and the time required for facial skin barrier function to recover using different microneedle lengths and numbers of applications. MATERIALS AND METHODS: Each side of a volunteer's face was randomly treated with one of the following treatments: five applications of 0.15-mm microneedles, five applications of 0.25-mm microneedles, 10 applications of 0.15-mm microneedles, or 10 applications of 0.25-mm microneedles. Transepidermal water loss, stratum corneum hydration, and skin erythema were measured at baseline, immediately after treatment, 4 hours after treatment, and 8 hours after treatment and at 24-hour intervals for 3 days. RESULTS: Prompt recovery of barrier function (within 72 hours) was observed after microneedle treatment. CONCLUSION: Microneedle treatment is simple and inexpensive, and the skin barrier disruption it causes resolves quickly. Therefore, it can serve as an effective physical method of enhancing transdermal delivery of medications for the treatment of many cosmetic and dermatological conditions.


Subject(s)
Drug Delivery Systems/instrumentation , Face , Microinjections/instrumentation , Needles , Skin Physiological Phenomena , Administration, Cutaneous , Adult , Female , Humans , Male , Water Loss, Insensible , Young Adult
17.
Opt Lett ; 37(9): 1457-9, 2012 May 01.
Article in English | MEDLINE | ID: mdl-22555703

ABSTRACT

We report an axial-asymmetric high-Q Fabry-Perot cavity supporting nondegenerate Hermite-Gaussian modes of the same mode order. Axial asymmetry of mirror surface was introduced by mechanically grinding off one side of a cylindrical mirror substrate without degrading the original mirror quality. The bases of the resulting Hermite-Gaussian modes were aligned with respect to the direction of grinding, making it possible to prescribe the mirror principal axes.

18.
Ann Oncol ; 23(2): 361-7, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21566150

ABSTRACT

BACKGROUND: Nomograms are statistics-based tools that provide the overall probability of a specific outcome. In our previous study, we developed a nomogram that predicts recurrence of early gastric cancer (EGC) after curative resection. We carried out this study to externally validate our EGC nomogram. PATIENTS AND METHODS: The EGC nomogram was established from a retrospective EGC database that included 2923 consecutive patients. This nomogram was independently externally validated for a cohort of 1058 consecutive patients. For the EGC nomogram validation, we assessed both discrimination and calibration. RESULTS: Within the follow-up period (median 37 months), a total of 11 patients (1.1%) experienced recurrence. The concordance index (c-index) was 0.7 (P = 0.02) and the result of the overall C index was 0.82 [P = 0.006, 95% confidence interval (CI) 0.59-1.00]. The goodness of fit test showed that the EGC nomogram had significantly good fit for 1- and 2-year survival intervals (P = 0.998 and 0.879, respectively). The actual and predicted survival outcomes showed good agreement, suggesting that the survival predictions from the nomogram are well calibrated externally. CONCLUSIONS: A preexisting nomogram for predicting disease-free survival (DFS) of EGC after surgery was externally validated. The nomogram is useful for accurate and individual prediction of DFS, patient prognostication, counseling, and follow-up planning.


Subject(s)
Adenocarcinoma/surgery , Neoplasm Recurrence, Local , Nomograms , Stomach Neoplasms/surgery , Adenocarcinoma/pathology , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prognosis , Stomach Neoplasms/pathology
19.
Phys Rev Lett ; 109(24): 243601, 2012 Dec 14.
Article in English | MEDLINE | ID: mdl-23368317

ABSTRACT

We report the first experimental observation of the cavity-QED microlaser spectrum, specifically the unconventional frequency pulling brought by a strong atom-cavity coupling at off resonance. The pulling is enhanced quadratically by the atom-cavity coupling to result in a sensitive response to the number of pumping atoms (2.1 kHz per atom maximally). Periodic variation of the pulling due to the coherent Rabi oscillation is also observed as the number of pumping atoms is increased across multiple thresholds.

20.
J Nanosci Nanotechnol ; 11(8): 7176-9, 2011 Aug.
Article in English | MEDLINE | ID: mdl-22103151

ABSTRACT

The sintered Ca(1-x-y)Dy(x)CeyMnO3 bodies were a single phase with a perovskite structure without any impurity phases. The calculated crystallite sizes of the Ca(1-x-y)Dy(x)CeyMnO3 were in the range of 43.3 to 63.3 nm. The composition significantly affected their microstructural and thermoelectric characteristics. The doped Dy led to both an increase in the electrical conductivity as well as the absolute value of the Seebeck coefficient, resulting in an enhanced power factor. The highest power factor (5.1 x 10(-4) Wm(-1) K(-2)) was obtained for Ca(0.8)Dy(0.2)MnO3 at 800 degrees C. In this study, we systematically discussed the thermoelectric properties of the Ca(1-x-y)Dy(x)CeyMnO3, with respect to the substitution of Dy and/or Ce for Ca.

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