Gender difference in the effect of uric acid on striatal dopamine in early Parkinson's disease.

BACKGROUND AND PURPOSE: High uric acid (UA) levels have been shown to exert a neuroprotective effect in Parkinson's disease (PD) by inhibiting oxidative stress in the nigrostriatal pathway. However, the association between striatal dopamine activity and UA level has not been clarified. METHODS: A total of 213 patients with early PD were enrolled. All patients underwent positron emission tomography using 18 F-N-(3-fluoropropyl)-2beta-carbon ethoxy-3beta-(4-iodophenyl) nortropane and a venous blood test for quantification of serum UA. All patients were stratified into either the lower UA group or the higher UA group using the median UA level. After normalizing the positron emission tomography images, differences in the regional standardized uptake value ratios (SUVRs) were analyzed with a volume-of-interest template. All tested SUVRs were also compared after categorizing patients by gender. RESULTS: The UA affected dopamine transporter SUVRs in different ways by gender. In female patients, the higher UA level group showed a smaller reduction in dopamine transporter uptake in the posterior putamen, whereas there was no such association observed in male patients. CONCLUSIONS: Higher UA levels were correlated with higher dopamine transporter uptake in the putamen in female patients with early PD. This finding suggests that UA has a neuroprotective effect, as demonstrated by the relatively preserved striatal dopamine activity in women.

Observation of incoherently coupled dark-bright vector solitons in single-mode fibers.

We report experimental observation of incoherently coupled dark-bright vector solitons in single-mode fibers. Properties of the vector solitons accord well with those predicted by the respective systems of incoherently coupled nonlinear Schrödinger equations. To our knowledge, this is the first experimental observation of temporal incoherently coupled dark-bright solitons in single-mode fibers.

Modulation of error monitoring in obsessive-compulsive disorder by individually tailored symptom provocation.

BACKGROUND: The enhanced error monitoring in patients with obsessive-compulsive disorder (OCD), typically measured with the error-related negativity (ERN), has been found to be temporally stable and independent of symptom expression. Here, we examined whether the error monitoring in patients with OCD could be experimentally modulated by individually tailored symptom provocation. METHOD: Twenty patients with OCD and 20 healthy controls performed a flanker task in which OCD-relevant or neutral pictures were presented prior to a flanker stimulus. An individualized stimulus set consisting of the most provoking images in terms of OCD symptoms was selected for each patient with OCD. Response-locked event-related potentials were recorded and used to examine the error-related brain activity. RESULTS: Patients with OCD showed larger ERN amplitudes than did control subjects in both the OCD-symptom provocation and neutral conditions. Additionally, while patients with OCD exhibited a significant increase in the ERN under the OCD-symptom provocation condition when compared with the neutral condition, control subjects showed no variation in the ERN between the conditions. CONCLUSIONS: Our results strengthen earlier findings of hyperactive error monitoring in OCD, as indexed by higher ERN amplitudes in patients with OCD than in controls. Importantly, we showed that the patients' overactive error-signals were experimentally enhanced by individually tailored OCD-symptom triggers, thus suggesting convincing evidence between OCD-symptoms and ERN. Such findings imply that therapeutic interventions should target affective regulation in order to alleviate the perceived threatening value of OCD triggers.

Welding fume exposure and chronic obstructive pulmonary disease in welders.

BACKGROUND: Occupational exposure is estimated to contribute 15% to the burden of chronic obstructive pulmonary disease (COPD). Welding fumes are suspected to accelerate the decline of lung function and development of COPD. AIMS: To examine the relationship between welding fume exposure and COPD in Korean shipyard welders. METHODS: The study involved a group of male welders working at two shipyards who underwent an annual health examination in 2010. Subjects completed a questionnaire about smoking habits and occupational history and a pulmonary function test (PFT) was carried out with strict quality control measures. Welding fume exposure concentrations were estimated using 884 measurements taken between 2002 and 2009 in one of the shipyards. Multiple linear and logistic regression was employed to evaluate the association between cumulative fume exposure and lung function parameters, controlling for age, height and cigarette smoking. RESULTS: Two hundred and forty subjects participated, with a mean age of 48 and mean work duration of 15 years. The mean cumulative fume exposure was 7.7mg/m(3). The prevalence of COPD was 15%. FEV1 and FVC showed non-significant negative correlations with cumulative fume exposure. Odds ratios of COPD were significantly elevated for the middle (3.9; 95% CI 1.4-13.3) and high exposure groups (3.8; 95% CI 1.03-16.2) compared with the low fume exposure group. CONCLUSIONS: Our findings support an association between welding fume exposure and increased risk of COPD. Further prospective study is needed to investigate whether this is a causal relationship.

Preemptive living-donor renal transplantation: outcome and clinical advantages.

INTRODUCTION: Kidney transplant recipients have a higher quality of life and consume fewer health care resources compared with patients on dialysis. However, optimal timing of transplantation has been controversial. Recent studies have clearly demonstrated that preemptive renal transplantation is associated with better graft survival, lower complications, and better cost-effective outcomes. We evaluated differential effects on long-term outcomes according to dialysis type/duration versus no dialysis. MATERIALS AND METHODS: We retrospectively analyzed 499 cases of first living-donor kidney transplantations performed in our center from January 1990 to January 2007. We compared 3 groups according to graft survival, acute and chronic rejection, postoperative complication, and delayed graft function rates. The mean duration of follow-up was 119.1 +/- 47.2 months. RESULTS: Among 499 cases, 81 cases were preemptive renal transplantations with 418 cases hemodialysis [HD], 343 cases, peritoneal dialysis [PD] 75 cases) performed after dialysis. The 1-, 5-, and 10-year graft survival rates were 98.8%, 89.5%, 79.4% among the preemptive renal transplantation group and 92.4%, 78.2%, and 69.2% and 85.3%, 74.5%, and 68.2% (P = .03) in the dialysis groups (HD, PD), respectively. The differential effect of pretransplantation HD or PD was not significant. However, the graft survival rates in the HD group were not significantly higher than the PD group (P = .61). The duration of dialysis was not associated with graft survival. CONCLUSION: We suggest that preemptive renal transplantation should be the first choice of treatment for patients with end-stage renal disease.

Hippocampal encoding of interoceptive context during fear conditioning.

Rodent models of auditory fear conditioning are often used to understand the molecular mechanisms regulating fear- and anxiety-related behaviors. Conditioning and extinction memories are influenced by contextual cues, and the reinstatement of conditioned fear occurs when the conditioning stimulus is presented in a context different from the extinction context. Although it has been proposed that internal state is a feature of context that could influence extinction, contributions of interoception to conditioning have not been experimentally addressed. Here we use ethanol (EtOH) to show that interoceptive cues are encoded through the hippocampus by mechanisms that involve increased phosphorylation of GluR1 on serine 845, and biophysical alterations in neuronal membranes that facilitate stabilization of surface-located calcium-permeable n-2-amino-3-(5-methyl-3-oxo-1,2-oxazol-4-yl) propanoic acid (AMPA) receptor (AMPAR) into membrane microdomains. Conflicting interoceptive cues during extinction and fear relapse testing resulted in a failure to consolidate extinction that was reversed by the administration of AMPAR antagonists immediately following the retrieval cue.

High-resolution CT appearance of miliary tuberculosis.

OBJECTIVE: The purpose of this study was to define the range of abnormalities and to assess the contribution of high-resolution CT (HRCT) in the evaluation of miliary tuberculosis involving the lung parenchyma. MATERIALS AND METHODS: The authors retrospectively reviewed HRCT scans of 11 patients with microbiologically or clinically proved miliary tuberculosis. RESULTS: In 10 patients, the most characteristic HRCT finding of miliary tuberculosis was the presence of small nodules uniformly distributed throughout both lungs. The profusion of nodules was numerous in all 10 patients. High-resolution CT scans showed both sharply and poorly defined, small nodules varying in sizes from 1 to 2 mm (n = 6), 1 to 3 mm (n = 2), and 1 to 4 mm (n = 2) in diameter. These nodules had a diffuse random distribution in the secondary lobule in all 10 patients. In 1 of the 10 patients with small nodules on HRCT, chest radiography had shown no evidence of miliary nodules in the lung. In addition to nodules, HRCT showed diffuse or localized reticular opacities superimposed on nodules in five patients, especially in the lower lung zones. In 1 of all 11 patients, ground-glass attenuation was the predominant abnormality seen on HRCT. CONCLUSION: We believe that in the appropriate clinical situation, miliary tuberculosis may be suggested on HRCT. Moreover, in cases with no evidence of miliary nodules on the chest radiograph, HRCT scan may depict miliary nodules in the lung parenchyma.

Can bone turnover markers correlate bone mass at the hip and spine according to menopausal period?

Changes in bone turnover with years since menopause (YSM) are responsible for bone loss and play a major role in osteoporosis. Although single measurements of the bone turnover marker appear unlikely to be clinically useful in predicting bone mineral density, the usefulness of these measurements in relation to the YSM has not been well established. The establishment of this relationship was the aim of this study. To address this issue, we have measured a battery of sensitive and specific markers of bone turnover in 272 women postmenopausal from -5 to 15 a, and the data was correlated with bone mineral density (BMD) at different skeletal sites measured utilizing dual-energy X-ray absorptiometry (DXA). Bone formation was assessed by serum osteocalcin (OC), and bone resorption by Pyr and D-pyr. The three markers and BMD were compared between the groups (YSM). Among the three markers, only Pyr exhibited a significant difference between pre and postmenopausal groups. In the aspect of correlation between bone turnover marker and BMD according to the groups (YSM), we found negative strong correlations between the BMD of lumbar spine (L2-4) vs. Pyr (P=0.01, r=-0.75) in the premenopausal group (-5 approximately 0 YSM), and we found negative correlation between the BMD of L2-4 vs. osteocalcin (P=0.05, r=-0.2 and P=0.01, r=-4).44) in the postmenopause groups (0 approximately 5 and 5 approximately 10 YSM). We concluded that Pyr in women -5 approximately 0 YSM and osteocalcin in women 0 approximately 10 YSM displayed negative correlation with BMD of L2-4.