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Gallium‐based liquid metal, eutectic gallium–indium alloy (EGaIn), is becoming a leading innovation in soft electronic devices due to its exceptional electronic conductivity and deformability. However, the formation of insulating oxide films on EGaIn surfaces poses a significant impediment to translating electrochemical reactions, thereby limiting its use as an electrochemical biosensor. Here, functionalized EGaIn electrodes with reduced‐graphene‐oxide assembled EGaIn core–shell particles (REGs) for soft and deformable electrochemical biosensors are presented. Exploiting EGaIn's capability as a reducing agent, REGs can undergo further modification with metal nanoparticles through additional galvanic replacement reactions. The REGs and metal‐coated REGs (M‐REGs) provide strong interfacial adhesion with the EGaIn current collector, exhibiting no exfoliation during and after the mechanical deformation. Moreover, RIDE and metal‐decorated RIDE (M‐RIDE) show excellent electrochemical sensing performances by taking advantage of the facile surface tunability of REGs, allowing simultaneous detection of ascorbic acid, dopamine, and uric acid, and enzymatic detection of glucose. The developed RIDE/M‐RIDE paves the way for utilizing EGaIn in the development of soft and deformable electrochemical biosensors. [ABSTRACT FROM AUTHOR]

Tracing fast nanopore‐translocating analytes requires a high‐frequency measurement system that warrants a temporal resolution better than 1 µs. This constraint may practically shift the challenge from increasing the sampling bandwidth to dealing with the rapidly growing noise with frequencies typically above 10 kHz, potentially making it still uncertain if all translocation events are unambiguously captured. Here, a numerical simulation model is presented as an alternative to discern translocation events with different experimental settings including pore dimension, bias voltage, the charge state of the analyte, salt concentration, and electrolyte viscosity. The model allows for simultaneous analysis of forces exerting on a large analyte cohort along their individual trajectories; these forces are responsible for the analyte movement leading eventually to the nanopore translocation. Through tracing the analyte trajectories, the Brownian force is found to dominate the analyte movement in electrolytes until the last moment at which the electroosmotic force determines the final translocation act. The mean dwell time of analytes mimicking streptavidin decreases from ≈6 to ≈1 µs with increasing the bias voltage from ±100 to ±500 mV. The simulated translocation events qualitatively agree with the experimental data with streptavidin. The simulation model is also helpful for the design of new solid‐state nanopore sensors. [ABSTRACT FROM AUTHOR]

2D transition‐metal dichalcogenide (TMDC) materials are promising candidates with excellent thermoelectric (TE) properties owing to their low dimensionality in electronic and phonon transport. However, the considerable coupling of the Seebeck coefficient and electrical conductivity in such TE materials eventually results in the limit of the TE power factor increase, which severely hinders potential TE device applications. Herein, an alternative approach is demonstrated for breaking the strong coupling between the Seebeck coefficient and electrical conductivity in single TE materials by adopting a novel stacked PtSe2/PtSe2 homostructure. By alternately piling low‐resistance (LR) PtSe2 (3 nm) onto high‐resistance (HR) PtSe2 (2 nm) as one unit, the Seebeck coefficient and electrical conductivity of such stacked homostructures can be greatly enhanced with slightly improved electrical conductivity, ultimately resulting in a TE power factor in three‐unit‐stacked homostructures that is ≈1,648% higher than that of a single PtSe2 (15 nm) layer with the same thickness. This enhancement is attributed to an independent increase in the Seebeck coefficient, which depends on the interface among the LR and HR PtSe2 layers. The findings pave the way for a method that, unlike power factor optimization in conventional thermoelectric materials, can only utilize the Seebeck coefficient and electrical conductivity of each layer in a stacked homostructure. [ABSTRACT FROM AUTHOR]

When a thermoelectric (TE) material is deposited with a secondary TE material, the total Seebeck coefficient of the stacked layer is generally represented by a parallel conductor model. Accordingly, when TE material layers of the same thickness are stacked vertically, the total Seebeck coefficient in the transverse direction may change in a single layer. Here, an abnormal Seebeck effect in a stacked two‐dimensional (2D) PtSe2/PtSe2 homostructure film, i.e., an extra in‐plane Seebeck voltage is produced by wet‐transfer stacking at the interface between the PtSe2 layers under a transverse temperature gradient is reported. This abnormal Seebeck effect is referred to as the interfacial Seebeck effect in stacked PtSe2/PtSe2 homostructures. This effect is attributed to the carrier‐interface interaction, and has independent characteristics in relation to carrier concentration. It is confirmed that the in‐plane Seebeck coefficient increases as the number of stacked PtSe2 layers increase and observed a high Seebeck coefficient exceeding ≈188 µV K−1 at 300 K in a four‐layer‐stacked PtSe2/PtSe2 homostructure. [ABSTRACT FROM AUTHOR]

A highly sensitive amperometric galactose biosensor was developed by encapsulating galactose oxidase within the graphene‐doped sol‐gel titania‐Nafion composite film on platinized glassy carbon electrode. Due to the combined electrocatalytic activity of graphene and Pt NPs on the electrode towards hydrogen peroxide as well as the mesoporous nature of the titania‐Nafion composite, the present galactose biosensor exhibited relatively fast response time under 2 s, high sensitivity of 40.6 mAM−1cm−2, and wide dynamic range over three orders of magnitude with a detection limit of 3.78×10−6 M (S/N=3). In addition, the biocompatible composite in the biosensor secures excellent long‐term stability. [ABSTRACT FROM AUTHOR]

The spin current is significantly limited by the spin‐orbit interaction strength, material quality, and spin‐mixing conductance at material interfaces. Such limitations lead to spin current decay at the interfaces, which severely hinders potential applications in spin‐current‐generating thermoelectric devices. Thus, methodical studies on the enhancement of spin currents are indispensable. Herein, a novel approach for enhancing the spin current injected into a normal metal, Pt, using interface effects with a ferromagnetic insulator, yttrium iron garnet (YIG), is demonstrated. This is accomplished by inserting atomically thin monolayer (ML), tungsten diselenide (WSe2) between Pt and YIG layers. A comparative study of longitudinal spin Seebeck effect (LSSE) measurements is conducted. Two types of ML WSe2 (continuous and large‐area ML WSe2 and isolated ML WSe2 flakes) are used as intermediate layers on YIG film. Notably, the insertion of ML WSe2 between the Pt and YIG layers significantly enhances the thermopower, VLSSE/ΔT by a factor of approximately 5.6 compared with that of the Pt/YIG reference sample. This enhancement in the measured LSSE voltages in the Pt/ML WSe2/YIG trilayer can be explained by the increased spin‐to‐charge conversion at the interface owing to the large spin‐orbit coupling and improved spin mixing conductance with the ML WSe2 intermediate layer. [ABSTRACT FROM AUTHOR]

Background: While a considerable number of cases with papulopustular rosacea (PPR) are resistant to conventional medications, therapeutic regimens are not currently established. Pulsed dye laser (PDL) and fractional microneedling radiofrequency (FMR) have previously demonstrated satisfactory results for anti‐angiogenesis, anti‐inflammation, and dermal remodeling. Aims: To evaluate the efficacy and safety of novel combination regimen with low‐dose oral isotretinoin, PDL, and FMR in the treatment of recalcitrant PPR. Patients and methods: A retrospective study was undertaken for recalcitrant PPR patients to evaluate the clinical course of novel combination regimen. Twenty‐five PPR patients who had failed in previous first‐line therapies were enrolled. They were treated with three sessions of PDL and FMR consecutively at 4‐week intervals, maintaining daily oral administration of 10 mg isotretinoin for 8 weeks. Objective assessments, erythema index measurement, and patients' subjective satisfaction were evaluated at each visit and 16 weeks after the final treatment. Results: At the final follow‐up visit, the number of papules and pustules decreased by 71%, and erythema index by 54% compared with baseline (P < 0.05 for both). Physician's global assessment based on rosacea severity score and patients' subjective assessments paralleled with these results. No serious side effect was observed during whole study periods. Conclusion: This novel combination regimen demonstrated satisfactory efficacy with reasonable safety profiles for the treatment of recalcitrant PPR. [ABSTRACT FROM AUTHOR]

RATIONALE: Volatile organic compounds (VOCs) are ubiquitous environmental pollutants that have a high vapor pressure at room temperature. Some VOCs have been classified as carcinogenic to humans by the International Agency for Research on Cancer (IARC), because they can bind to DNA and cause cell mutations. Therefore, monitoring of VOCs in human urine is very important to evaluate the correlation between exposure to VOCs and human disease. METHODS:We have developed an improved analyticalmethod for the simultaneous determination of VOCswith awide range of polarities in human urine samples by headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography/mass spectrometry (GC/MS). In the improved method, a bi-polar carboxen-polydimethylsiloxane (CAR/PDMS) fiber was used for the optimized extraction of 15 VOCs with a wide range of polarities, including benzene, toluene, ethylbenzene, xylenes (BTEX), alkylbenzenes, cresols, and naphthalene, in human urine samples. Extracted VOCs from the human urine were effectively separated by GC using a mid-polarity column (DB-35, 35% phenylmethylpolysiloxane) and monitored by MS using extracted ion monitoring (EIM) mode. RESULTS: Under the optimized method, the linearity of the calibration curves was greater than 0.993. The limits of detection (LODs) at a signal-to-noise (S/N) ratio of 3 were 0.3-0.6 ng/mL. The coefficients of variation were in the range of 0.1-9.7% for within-day variation and 0.2-14.2% for day-to-day variation. CONCLUSIONS: Themethod was shown to be rapid and simple for the simultaneous determination of VOCswith awide range of polarities in human urine and it could be applied to monitoring and to biomedical investigations to check exposure to VOCs. [ABSTRACT FROM AUTHOR]

We aimed to compare Dysport (abobotulinumtoxinA, Ipsen Biopharm, Slough, UK) and Botox (onabotulinumtoxinA, Allergan, Irvine, CA, USA) at a 2.5:1 ratio in the treatment of cervical dystonia (CD). A Dysport/Botox ratio of lower than 3:1 was suggested as a more appropriate conversion ratio, considering its higher efficacy and more frequent incidence of adverse effects not only in the treatment of CD but also in other focal movement disorders. A randomized, double-blind, multicenter, non-inferiority, two-period crossover study was done in CD, with a duration of at least 18 months. Patients were randomly assigned to treatment for the first period with Dysport or Botox, and they were followed up for 16 weeks after the injection. After a 4-week washout period, they were switched to the other formulation and then followed up for 16 weeks. The primary outcome was the changes in the Tsui scale between the baseline value and that at 1 month after each injection. A total of 103 patients were enrolled, and 94 completed the study. Mean changes in the Tsui scale between baseline and 4 weeks after each injection tended to favor Botox; however, this was not statistically significant (4.0 ± 3.9 points for the Dysport treatment vs. 4.8 ± 4.1 points for Botox; 95% confidence interval, −0.1-1.7; P = 0.091). The mean change of the Toronto western spasmodic torticollis rating scale score, the proportion of improvement in clinical global impression and patient global impression, and the incidences of adverse events were not significantly different between the two treatments. With regard to safety and efficacy, Dysport was not inferior to Botox in patients with CD at a conversion factor of 2.5:1. [: NCT00950664] © The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Background: Freezing of gait is a common and disabling symptom of parkinsonism. However, the corresponding anatomic structures have yet to be clearly elucidated. Methods: We performed diffusion tensor imaging on 40 subjects with white matter changes. We compared apparent diffusion coefficient values and fraction anisotropy values of 7 candidate anatomic structures between 14 patients with freezing of gait (freezing of gait group) and 26 without freezing of gait (control group). Results: Fraction anisotropy values of the bilateral pedunculopontine nucleus, bilateral superior premotor cortex, right orbitofrontal area, and left supplement motor area were significantly lower in the freezing of gait group than in the control group. In contrast, there were no significant differences in apparent diffusion coefficient values between freezing of gait and control groups. Conclusions: Our findings suggest that the bilateral pedunculopontine nucleus, bilateral superior premotor cortex, right orbitofrontal area, and left supplement motor area are closely related to freezing of gait. © 2011 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Background: Although leucine-rich repeat kinase 2 ( LRRK2) is the gene most commonly linked to autosomal dominant inherited Parkinson's disease (PD), there have been few reports in Asia, probably because of population-specific differences in allele frequencies. Methods: We identified a large Korean PD family with the p.Tyr1699Cys mutation in LRRK2 and analyzed genealogical, clinical, and genetic data from the family. Results: Although the clinical findings of these patients were indistinguishable from those of patients with sporadic PD, the patients with the p.Tyr1699Cys mutation demonstrated clinical heterogeneity including differences in age at onset, rate of disease progression, clinical phenotype, and prognosis. Conclusions: This is the first report describing an Asian PD family with the p.Tyr1699Cys mutation in LRRK2. The affected members of this family showed clinical heterogeneity. © 2011 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Objective. To evaluate the usefulness of video pneumatic otoscopy (VPO) for the diagnosis of conductive hearing loss (CHL) with normal tympanic membranes (TM).Study Design. Prospective study.Setting. Tertiary care hospital.Subjects and Methods. Thirty-seven ears with CHL and 9 control ears with normal TMs were included. The VPO was performed preoperatively in all patients. The authors captured TM images in 3 stages of the VPO (static, positive, and negative pressure stage) in all subjects and measured the amount of relative position differences of the umbo. Pure-tone audiometry and temporal bone computed tomography (TBCT) were performed preoperatively. The possible causes of hearing loss were evaluated during exploratory tympanotomy in the patients with CHL.Results. Fifteen patients had stapedial fixation, 10 had fixation of the malleus or incus (MIF), and 12 had ossicular discontinuity. The positional differences between the negative and positive pressure stage of the MIF group were significantly smaller between the CHL and control groups (P = .001). The air-bone gap showed no significant difference among the CHL groups. The sensitivity, specificity, and diagnostic accuracy of the VPO for the diagnosis of MIF, with a cutoff value of 1.5% or less in terms of the movement of umbo, were 80.0%, 92.6%, and 89.2%, respectively. These findings were comparable to those of the TBCT, which were 90.0%, 85.2%, and 86.5%, respectively.Conclusion. The VPO is a simple, noninvasive, and accurate tool for the differential diagnosis of CHL with a normal TM. [ABSTRACT FROM PUBLISHER]

Abstract: Objective: To investigate whether preserving the external jugular vein (EJV) in neck dissection reduces postoperative edema of the face and neck. Study Design: A prospective, randomized controlled trial. Setting: A tertiary hospital. Subjects and Methods: Thirty-eight subjects were randomly assigned to two groups: EJV preservation versus sacrifice during neck dissection after stratification according to the neck dissection extent and type, the previous treatment, the primary site, and the reconstruction type. The relative soft-tissue thickness was evaluated by follow-up computed tomography (CT) scans at one week and four to five weeks postoperatively and compared with preoperative findings. The preserved EJV patency was also determined by contrast enhancement of EJV on follow-up CT scans. In addition, the scores for pain/discomfort on the upper neck/face and laryngeal edema were recorded at each time point. Results: Relative soft-tissue thickness reached up to 160 percent of preoperative status at the hyoid and cricoid levels at one week postoperatively but resolved at four to five weeks. EJV preservation reduced the soft-tissue thickness significantly compared with EJV sacrifice (P < 0.05) at one week postoperatively, particularly at the mandible and hyoid level. All preserved EJVs remained patent at one week, and 18 of 19 remained patent at four to five weeks. In addition, EJV preservation diminished the discomfort/pain of the upper neck/face compared with EJV sacrifice at one week (P = 0.036). The extent of laryngeal edema did not differ between the two groups. Conclusion: EJV preservation may reduce immediate postoperative neck edema and pain/discomfort related to neck dissection. [Copyright &y& Elsevier]

Abstract: Objective: The purpose of this study is to compare the efficacy of intratympanic steroid injection (ITSI) with that of systemic steroids as an initial treatment of sudden sensorineural hearing loss (SNHL) with diabetes. Study Design: Prospective, nonrandomized multicenter clinical trial. Setting: Multicenter study in Busan and Masan, South Korea. Subjects and Methods: A total of 114 sudden SNHL patients who were diagnosed with diabetes were divided into peroral (PO) group (n = 48), intravenous (IV) group (n = 32), and intratympanic (IT) group (n = 34). In the PO group, prednisolone was used orally for 10 days, per schedule. In the IV group, prednisolone was administered intravenously for seven days, followed by oral administration of tapered doses for another several days. In the IT group, dexamethasone was injected into the tympanic cavity four times within a two-week period. Hearing outcome was assessed before and after the treatment. Results: All groups showed significant improvement with criteria of 15 dB (P < 0.05). However, there was no significant difference in hearing gain and recovery rate among groups (P > 0.05). Systemic steroid treatment was stopped for two patients in the IV group and for one in the PO group due to uncontrolled hyperglycemia. However, in the IT group, there were no patients who failed to control their blood sugar level. Conclusion: ITSI is as effective as systemic steroid treatment for sudden SNHL patients with diabetes and it can avoid undesirable side effects. Therefore, we consider ITSI to be a more reasonable alternative as an initial treatment for sudden SNHL patients with diabetes. [Copyright &y& Elsevier]

Parkinson's disease (PD) with autonomic dysfunction is difficult to differentiate from Parkinsonism-predominant multiple system atrophy (MSA-p). This study aimed to analyze the validity of MIBG scintigraphy for PD with autonomic dysfunction and MSA-p. Thirty-nine patients (PD: 27 patients, MSA-p type: 12) and 12 age-matched controls were prospectively enrolled and underwent MIBG scintigraphy and autonomic function test (AFT). We separately calculated early and delayed heart-to-mediastinal ( H/ M) ratio and washout rates (WRs). AFT was composed of sympathetic skin reflex and parasympathetic tests based on heart rate variability. Abnormal AFT was observed in 17 (63%) of PD and 10 (83%) of MSA-p. On comparing PD with abnormal AFT with MSA-p, either the early or delayed H/ M ratio in PD was not different from that in MSA-p ( P > 0.05). Only the WR could differentiate PD with abnormal AFT from MSA-p (47.07 ± 57.48 vs. 31.39 ± 31.52, respectively) ( P = 0.026). According to the results, WR may be more useful than the early and delayed H/ M ratio to distinguish MSA-p from PD with abnormal AFT. Furthermore, the MIBG uptake did not reflect the disease duration or severity. © 2009 Movement Disorder Society [ABSTRACT FROM AUTHOR]

To investigate whether Helicobacter pylori (HP) infection affects the clinical response to levodopa and whether its eradication could improve motor fluctuation in patients with Parkinson's disease (PD). Using the [13C] urea breath test, we monitored HP infection in 65 patients with PD and motor fluctuations of the 'wearing-off' or delayed 'on' types, with or without dyskinesia. We compared the clinical features and response to L-dopa between HP noninfected (n = 30) and HP infected patients (n = 35) by reviewing home diaries kept for 72 hours. Among HP infected patients, we compared the differences in L-dopa 'onset' time, 'on-time' duration, and scores on the motor examination section of the Unified PD Rating Scale (UPDRS-III) during the medication 'on' phase before and after HP eradication. There were no differences in the age, disease duration, Hoehn and Yahr stage, UPDRS-III score, L-dopa daily dose, and frequency of dyskinesia between HP noninfected and HP infected groups. However, L-dopa 'onset' time was longer and 'on-time' duration was shorter in HP infected patients than in HP noninfected patients (78.4 ± 28.2 vs. 56.7 ± 25.1 and 210.0 ± 75.7 vs. 257.7 ± 68.9 min, respectively, P < 0.05). HP eradication improved the delay L-dopa 'onset' time and short 'on-time' duration (to 58.1 ± 25.6 and to 234.4 ± 66.5 min, respectively, P < 0.05). These data demonstrated that HP infection could interfere with the absorption of L-dopa and provoke motor fluctuations. HP eradication can improve the motor fluctuations of HP infected patients with PD. © 2008 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Voluntary movement mediated by skeletal muscle relies on endplate acetylcholine receptors (AChR) to detect nerve-released ACh and depolarize the muscle fiber. Recent structural and mechanistic studies of the endplate AChR have catalyzed a leap in our understanding of the molecular steps in this chemical-to-electrical transduction process. Studies of acetylcholine binding protein (AChBP) give insight into ACh recognition, the first step in activation of the AChR. An atomic structural model of the Torpedo AChR at a resolution of 0.4 nm, together with single-ion channel recording methods, allow tracing of the link between the agonist binding event and gating of the ion channel, as well as determination of how the channel moves when it opens to allow flow of cations. Structural models of the human AChR enable precise mapping of disease-causing mutations, while studies of the speed with which single AChR channels open and close cast light on pathogenic mechanisms. [ABSTRACT FROM AUTHOR]

Repetitive transcranial magnetic stimulation (rTMS) has been used as a potential therapeutic tool in Parkinson's disease (PD). However, the therapeutic value and/or the placebo effect of rTMS on PD remain to be elucidated. To investigate the therapeutic value and/or placebo effect of rTMS in PD, we compared the motor section of unified PD rating scale (UPDRS III) and the amount of extracellular dopamine concentration using [(11)C] raclopride PET before and after two sessions of rTMS in 9 PD patients. During a consecutive 2 days while off-medication, two series of 15 trains of 5 Hz-frequency rTMS (intensity, 90% of the resting motor threshold) were applied to the hand area of more severely symptomatic motor cortex (MC). After unilateral rTMS of MC, mean raclopride binding potentials (BPs) were reduced not only in putaminal and caudate areas on the stimulated side (-4.9% and -6.5%, respectively) (P > 0.05) but also in putaminal and caudate areas of nonstimulated hemispheres (-6.6%, P > 0.05 and -12.1%, P = 0.049, respectively). UPDRS III scores were significantly decreased (35.0 +/- 14.1 to 32.0 +/- 13.4, P = 0.049). A reduction of raclopride BP in nonstimulated ventral striatum by unilateral rTMS supports the placebo response during rTMS. [ABSTRACT FROM AUTHOR]

Repetitive transcranial magnetic stimulation (rTMS) has been used as a potential therapeutic tool in Parkinson's disease (PD). However, the therapeutic value and/or the placebo effect of rTMS on PD remain to be elucidated. To investigate the therapeutic value and/or placebo effect of rTMS in PD, we compared the motor section of unified PD rating scale (UPDRS III) and the amount of extracellular dopamine concentration using [11C] raclopride PET before and after two sessions of rTMS in 9 PD patients. During a consecutive 2 days while off-medication, two series of 15 trains of 5 Hz-frequency rTMS (intensity, 90% of the resting motor threshold) were applied to the hand area of more severely symptomatic motor cortex (MC). After unilateral rTMS of MC, mean raclopride binding potentials (BPs) were reduced not only in putaminal and caudate areas on the stimulated side (−4.9% and −6.5%, respectively) ( P > 0.05) but also in putaminal and caudate areas of nonstimulated hemispheres (−6.6%, P > 0.05 and −12.1%, P = 0.049, respectively). UPDRS III scores were significantly decreased (35.0 ± 14.1 to 32.0 ± 13.4, P = 0.049). A reduction of raclopride BP in nonstimulated ventral striatum by unilateral rTMS supports the placebo response during rTMS. © 2007 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Transcranial sonography (TCS) is potentially useful for the diagnosis of Parkinson's disease (PD). However, studies on TCS have so far been restricted to European populations. To investigate the efficacy of TCS in Korean PD patients and its correlation with the clinical features, we carried out midbrain TCS in 43 PD patients and 35 normal controls and evaluated the area of the substantia nigra (SN) hyperechogenicity and its ratio to the area of the whole midbrain. In 16 subjects (21%), TCS was unsuccessful due to insufficient acoustic temporal bone windows. The mean area of bilateral SN hyperechogenicity and its ratio to the midbrain area were greater in the PD patients than that in the controls (P < 0.01). In the PD patients, the area of SN hyperechogenicity and its ratio to the individual midbrain area were moderately correlated with the PD duration (r = 0.526 and 0.536, P = 0.01, respectively) but not with the age, UPDRS motor scores or H-Y stage. There was no difference in the SN hyperechogenicity between the tremor-dominant, akinetic-rigid, and mixed-type PD patients. In conclusion, midbrain TCS is an effective diagnostic tool for detecting PD in the Korean population. However, it does not reflect the severity or phenotypes of parkinsonism. [ABSTRACT FROM AUTHOR]

Tongue tremor is a rare form of focal tremor. Even though the dysfunction of the dentato-rubro-olivary circular pathway has been proposed as its mechanism, the origin of the rhythmic activities remains unknown. We experienced a case of isolated tongue tremor after the removal of a cerebellar pilocytic astrocytoma. To localize the activated structures corresponding to the isolated tongue tremor, we analyzed subtracted ictal SPECT coregistered to MRI (SISCOM). SISCOM demonstrated multiregional hyperperfusion including the Guillain-Mollaret triangular and extratriangular structures. The activation of the inferior olive and red nucleus and accompanying extratriangular structures might be related to the isolated tongue tremor. [ABSTRACT FROM AUTHOR]

Olfactory deficit is known to occur frequently in Parkinson's disease (PD). This study aimed to explore olfactory deficit in PD and to investigate its possible correlation with the disease severity or the depth of the olfactory sulcus. Fifty-nine PD patients and 25 normal controls were examined by the odor identification test with the crosscultural smell identification test (CC-SIT). Among these subjects, the depth of the olfactory sulcus of 42 PD patients and 8 controls was measured in the plane of the posterior tangent through the eyeballs using the coronal view brain MRI. The CC-SIT scores of the PD patients were significantly lower than those of the normal control ( P < 0.001). However, CC-SIT did not correlate with the disease duration, H-Y stage, score of UPDRS Part III, or the depth of either side of the olfactory sulcus ( P > 0.05). Our study confirms that CC-SIT is a helpful test in detecting the olfactory deficit in Korean PD patients. The absence of correlation of olfactory deficit with the disease severity or the depth of olfactory sulcus may suggest that olfactory loss precede the development of motor signs and not be a primary consequence of damage to the olfactory sulcus. © 2007 Movement Disorder Society [ABSTRACT FROM AUTHOR]

We developed an analytical method for a simple, sensitive and simultaneous determination of oxidized nucleosides in urine using column-switching liquid chromatography-electrospray/tandem mass spectrometry (LC-ESI/MS/MS). We connected two columns through a six-way switching valve and effectively separated nucleosides in the urine from the interference by column-switching liquid chromatography. We monitored separated nucleosides using positive ionization tandem mass spectrometry in selective reaction monitoring (SRM) mode. The calibration ranges of nucleosides were 0.2-100 nmol/mL. The linearity of the method was 0.994-0.999, and the limits-of-detection (LOD) at a signal-to-noise (S/N) ratio of 3 were 0.1-0.2 nmol/mL. The coefficients of variation were in the range 2.28-11.74% for within-day variation and 4.36-11.15% for day-to-day variation, respectively. To explore the relationship between breast cancer and the nucleosides level in human urine, we measured the concentrations of nucleosides in female patients with breast cancer ( n = 30) and in normal female subjects ( n = 30). The concentration of nucleosides was significantly increased in patients with breast cancer when compared with the normal controls (1-methyladenosine; p < 0.005, N2, N2-dimethylguanosine; p < 0.01, 5-hydroxymethyl-2′-deoxyuridine; p < 0.001, 8-hydroxy-2-deoxyguanosine; p < 0.001). Therefore, the elevated levels of nucleosides could be used as an important biomarker for breast-cancer research. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A simple and highly sensitive method for the quantification of dehydroepiandrosterone-3-sulfate (DHEAS) in human plasma was developed. DHEAS was directly determined in plasma using column-switching liquid chromatography/mass spectrometry (LC-MS). The plasma was filtered with a membrane filter. The filtrate was injected onto a pre-column without further sample preparation such as extraction or derivatization. The pre-column was washed with an aqueous solution to remove interference and the analyte was eluted into a reversed-phase C18 analytical column for separation and detection using a column-switching valve. The calibration range of DHEAS was 0.01-10 µmol/L, and the linearity of the method was 0.999. The limit of detection (LOD) at a signal-to-noise (S/N) ratio of 3 was 5 nmol/L. The accuracy and precision (%CV) were less than 10% in within-day and day-to-day variations. To explore the relationship between Alzheimer's disease and the DHEAS level in human plasma, the concentrations of DHEAS in female patients with Alzheimer's disease ( n = 20) and in normal female subjects ( n = 20) were measured. The level of DHEAS was significantly decreased in the plasma of patients with Alzheimer's disease ( p < 0.0002) compared with that in normal subjects. From the results, we concluded that our method is sufficiently sensitivity and reliability for the quantification of DHEAS in clinical samples. Plasma DHEAS concentration could be an important marker to understand the pathogenesis of Alzheimer's disease. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Valvular heart disease, associated with ergot derivative dopamine agonists, has been reported in patients with Parkinson's disease (PD). There are few comparative studies on the frequency, severity, and dose dependency of valvular disease associated with ergot derivatives. We analyzed these factors in 58 PD patients who were taking ergot derivatives (22 were taking bromocriptine and 36 were taking pergolide) and compared them with 20 age-matched controls based on the two-dimensional echocardiographic findings. Aortic, mitral, and tricuspid valvular thicknesses, as well as tenting areas and tenting distance of the mitral valve were measured. We also assessed the correlation between the cumulative or daily doses of ergot derivatives and each valvular parameter. There was no significant increase in the frequency of valvulopathy in the PD patients taking bromocriptine or pergolide. We identified a positive correlation between the daily dose of pergolide and the tenting area of the mitral valve ( r = 0.385; P = 0.020). However, other valvular parameters were not found to correlate with the age, disease duration, treatment duration, or dosage of medication. Our study failed to uncover definitive harmful effects of ergot derivative dopamine agonists on cardiac valves; this is considering the relatively lower daily doses than other reported cases. To establish a dosage dependency with valvulopathy, a more detailed study with higher doses of ergot derivatives for longer duration of treatment may be needed. © 2006 Movement Disorder Society [ABSTRACT FROM AUTHOR]

Please cite this paper as: Metabolic alterations of DHEA and cholesterol sulphates in the hair of patients with acne measured by liquid chromatography-mass spectrometry. Experimental Dermatology 2010; 19: 694-696. Abstract: As the hormonal levels in scalp hair reflects the condition of skin appendage, the level of dehydroepiandrosterone-3-sulphate (DHEAS) and cholesterol sulphate (CS) was evaluated in scalp hair obtained from patients with acne. The hair samples were extracted by alkaline solution and were analysed by liquid chromatography-mass spectrometry coupled to column switching system. The levels of DHEAS in scalp hair of women with acne were higher ( P < 0.001) than controls, while the levels of CS in scalp hair of women and men with acne were higher ( P < 0.001) than both control subjects. Increased hair levels of both DHEAS and CS could indicate acne development because of its direct action or stimulatory effect on local enzyme activity. It may be also helpful to understand the pathogenesis of acne based on follicular retention hyperkeratosis and increased sebum production of both steroid sulphates. [ABSTRACT FROM AUTHOR]

Novel, low‐voltage, high‐detectivity, solution‐processed, flexible near‐infrared (NIR) photodetectors for optoelectronic applications are realized and their optoelectronic properties are investigated for the first time. This is achieved by synthesizing Ag2Se nanoparticles (NPs) in aqueous solutions, and depositing highly crystalline Ag2Se thin films at 150 °C with redistributed Ag2Se NPs in aqueous inks. The high conductivity and low trap concentration of the 150 °C annealed Ag2Se films result from the Ag formed inside the films and the improved film quality, respectively. These factors are both critical for the realization of high‐performance flexible photodetectors. The fabricated device exhibits a high detectivity of 7.14 × 109 Jones (above 1 × 109) at room temperature, delivering low power consumption. This detectivity is superior to those of reported low band‐gap semiconductor systems, although the device has undergone 0.38% compressive and tensile strains. Moreover, the performance of the device is better than that of MoS2‐based phototransistors, black arsenic phosphorus field‐effect transistors, or commercial thermistor bolometers at room temperature (D* ≈ 108 Jones), and is exposed to mid‐infrared light. [ABSTRACT FROM AUTHOR]

Objectives: The inferior parathyroid glands receive blood supply from the inferior thyroid artery. The anatomic relationship of the inferior thyroid artery and recurrent laryngeal nerve (RLN) can be described in 3 different patterns. We reconsidered the anatomic relationship of these structures and mentioned the method to maintain vascular supply of inferior parathyroid gland during central neck dissection (CND) according to their anatomical relationship. Methods: For removal of fibrofatty tissue in central neck compartment, dissection proceeds along RLN. During the process, surgeons should be careful not to injure the inferior parathyroid gland. Results: To preserve the inferior parathyroid gland, dissection should proceed along RLN in the medial side of inferior parathyroid gland, if inferior parathyroid gland usually receives blood supply from posterolateral vascular pedicle. In cases in which inferior thyroid artery travels deep to right RLN and right parathyroid gland receives blood supply from posteromedial vascular pedicle, CND should be carefully performed along the lateral side of inferior parathyroid gland to preserve posteromedial vascular pedicle. Conclusions: To preserve the function of inferior parathyroid gland, the anatomical relationship between inferior thyroid artery and RLN should be understood. The direction of dissection along the RLN should be changed according to their anatomical pattern. [ABSTRACT FROM AUTHOR]

Objectives: We investigated extrathyroidal extension (ETE) through frozen biopsy for intraoperative decision‐making in patients with papillary thyroid cancer (PTC). Methods: During the period of the study an operation was performed in 268 patients with PTC and ETE was evaluated using intraoperative frozen biopsies of thyroid tissue. Results: ETE was confirmed in 54 patients (20%) on frozen biopsy. Fifty‐three patients among 54 patients showing ETE on frozen biopsy were confirmed on permanent pathologic analysis. Accordingly, frozen biopsy had a sensitivity of 66%, a specificity of 99%, a positive predictive value of 98%, and a negative predictive value of 87%. Tumor size (odds ratio 4.373; confidence interval 2.257‐8.475, P <. 001) was an independent factor for predicting ETE on frozen biopsy. Conclusions: Intraoperative frozen biopsy can be a useful tool in identifying the presence of ETE. It can also help the operator decide the extent of surgery and central neck dissection in patients with PTC. [ABSTRACT FROM AUTHOR]