Search for bosonic superweakly interacting massive dark matter particles with the XMASS-I detector

Bosonic superweakly interacting massive particles (super-WIMPs) are a candidate for warm dark matter. With the absorption of such a boson by a xenon atom, these dark matter candidates would deposit an energy equivalent to their rest mass in the detector. This is the first direct detection experiment exploring the vector super-WIMPs in the mass range between 40 and 120 keV. With the use of 165.9 day of data, no significant excess above background was observed in the fiducial mass of 41 kg. The present limit for the vector super-WIMPs excludes the possibility that such particles constitute all of dark matter. The absence of a signal also provides the most stringent direct constraint on the coupling constant of pseudoscalar super-WIMPs to electrons. The unprecedented sensitivity was achieved exploiting the low background at a level 10(-4)  kg-1 keVee-1 day-1 in the detector.

Differential impact of unrecognised brain infarction on stroke outcome in non-valvular atrial fibrillation

There has been little information regarding the impact of unrecognised brain infarctions (UBIs) on stroke outcome in patients with non-valvular atrial fibrillation (NVAF). By using volumetric analysis of ischaemic lesions, we evaluated the potential impact of UBIs on clinical outcome according to their presence and categorised type. This study enrolled 631 patients with NVAF having no clinical stroke history. UBIs were categorised into three types as territorial, lacunar, or subcortical. We collected stroke severity, functional outcome at three months, and the total volume of UBIs and acute infarction lesions. We investigated the association between clinical outcome and the type or volume of UBI, using a linear mixed model and logistic regression analysis. UBIs were detected in 285 (45.2 %) patients; territorial UBIs were observed in 24.4 % of patients (154/631), lacunar UBIs in 25 % (158/631), and subcortical UBIs in 15.7 % (99/631). Although initial stroke severity was not different between patients with UBIs and those without, those with UBIs had less improvement during hospitalisation, leading to poorer outcome at three months. Among the three types of UBIs, only territorial UBIs were associated with poor outcome, especially in patients with relatively smaller acute infarction volume. UBIs, in particular, territorial UBIs, may be considered as predictors for poor outcome after ischaemic stroke in patients with NVAF. Our results suggest that the impact of UBIs on clinical outcome differs according to the type of UBIs and the acute stroke severity.

Comparison of stent retriever and intra-arterial fibrinolysis in patients with acute ischaemic stroke

BACKGROUND AND PURPOSE

Although the stent retriever (SR) has shown a better reperfusion rate and clinical outcome than the older generation mechanical clot retrieval device, it is uncertain whether the SR is superior to intra-arterial fibrinolysis (IAF).

METHODS

Ischaemic stroke patients who were treated with SR or IAF as initial endovascular treatment modality for unilateral arterial occlusion in the anterior circulation were included. Successful reperfusion was defined as Thrombolysis in Cerebral Infarction grade ≥2b. A favourable clinical outcome was defined as a modified Rankin Score ≤2 at 3 months.

RESULTS

Between January 2009 and May 2012, 55 patients were treated with SR and 50 patients were treated with IAF. The baseline characteristics were similar between the two groups except for the occlusion site and rescue treatment. In binary logistic regression analysis adjusted for the occlusion site and rescue treatment, SR was independently associated with increased successful reperfusion [82.0% vs. 47.3%; odds ratio (OR) 5.21; 95% confidence interval (CI) 1.92-14.14) and a more favourable clinical outcome at 3 months (54.0% vs. 43.6%; OR 3.40; 95% CI 1.31-8.84). The frequency of symptomatic intracranial haemorrhage and mortality at 3 months was not different between the two groups.

CONCLUSIONS

Stent retriever was as safe as and more effective than IAF. Our findings suggest that SR may be considered as an initial modality rather than IAF in acute stroke patients who undergo endovascular treatment.

Management of gastric epithelial neoplasia in patients requiring esophagectomy for esophageal cancer

Esophageal squamous cell carcinoma is occasionally associated with malignancies located in other regions of the alimentary tract, as well as in the head, neck, and upper respiratory tract. The stomach is most commonly used for reconstruction of the alimentary tract after esophagectomy for esophageal cancer. When synchronous tumors are located in the stomach, it is often unsuitable for use in esophageal reconstruction. In such cases, an invasive procedure involving anastomosis between the esophagus and the colon must be performed. However, this procedure is associated with a high incidence of mortality and morbidity. Seven patients with synchronous esophageal cancer and gastric epithelial neoplasia were encountered. First, endoscopic submucosal dissection (ESD) was performed for the gastric epithelial neoplasia. Then, following successful ESD, Ivor-Lewis esophagectomy for esophageal cancer was planned 1 to 2 weeks later. A total of 11 gastric epithelial lesions were found in seven patients. En bloc resection by ESD was possible in all 11 lesions and histologically complete resection was achieved in all 11 lesions. Follow-up endoscopy was done 1-2 weeks after ESD; six patients with well-healing ulcers underwent esophagectomy the next day (8 or 15 days after ESD). In one patient with a poorly healed ulcer, a second follow-up endoscopy was done 1 week later and then esophagectomy was performed the next day (22 days after ESD). Post-surgical complications related to ESD, such as bleeding or mediastinal leak, were not seen in any of the seven patients. In patients with synchronous esophageal cancer and gastric epithelial neoplasia, ESD for gastric epithelial neoplasia followed by Ivor-Lewis esophagectomy 1 to 2 weeks later is an effective choice of treatment.

Ultra-low gamma-ray measurement system for neutrinoless double beta decay

An experiment for the detection of 0νβ(+)/EC and 0νEC/EC in 92Mo nuclei has been carried out with a scintillating crystal, CaMoO4, in coincidence with the HPGe detector. We study the background events inside the event selection window for 0ν β(+)/EC decays of CaMoO4 detector. For 51.2 days of data taking period, we didn't observe any event in the neutrinoless EC/EC decay event window. The (92)Mo 0νβ(+)/EC decay half-life limit was set to 0.61×10(20) years with a 90% confidence by method of Feldman and Cousins. This ultra-low gamma ray measurement utilizing coincidence technique can be used for the resonant EC/EC decay process of some nuclei which is potentially important for neutrinoless double beta decay process.

The role of external defects in chemical sensing of graphene field-effect transistors

A fundamental understanding of chemical sensing mechanisms in graphene-based chemical field-effect transistors (chemFETs) is essential for the development of next generation chemical sensors. Here we explore the hidden sensing modalities responsible for tailoring the gas detection ability of pristine graphene sensors by exposing graphene chemFETs to electron donor and acceptor trace gas vapors. We uncover that the sensitivity (in terms of modulation in electrical conductivity) of pristine graphene chemFETs is not necessarily intrinsic to graphene, but rather it is facilitated by external defects in the insulating substrate, which can modulate the electronic properties of graphene. We disclose a mixing effect caused by partial overlap of the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) of adsorbed gas molecules to explain graphene's ability to detect adsorbed molecules. Our results open a new design space, suggesting that control of external defects in supporting substrates can lead to tunable graphene chemical sensors, which could be developed without compromising the intrinsic electrical and structural properties of graphene.

The association between asymptomatic coronary artery disease and CHADS2 and CHA2 DS2 -VASc scores in patients with stroke

BACKGROUND AND PURPOSE

CHADS2 and CHA2 DS2 -VASc scores are measurement tools that stratify thromboembolic risk in patients with non-valvular atrial fibrillation, and are predictive of cerebral atherosclerosis, fatal stroke and ischaemic heart disease. Patients with higher CHADS2 and CHA2 DS2 -VASc scores are more likely to have had an akinetic/hypokinetic left ventricular segment or a recent myocardial infarction, all of which are associated with coronary artery disease (CAD). Most of the CHADS2 score components are also risk factors for atherosclerosis. Thus, CHADS2 and CHA2 DS2 -VASc scores may be predictive of CAD.

METHODS

In all, 1733 consecutive patients with acute ischaemic stroke who underwent multi-slice computed tomography coronary angiography were enrolled. The association of CHADS2 and CHA2 DS2 -VASc scores with the presence and severity of CAD was investigated.

RESULTS

Of the 1733 patients, 1220 patients (70.4%) had any degree of CAD and 576 (33.3%) had significant CAD (≥ 50% stenosis in at least one coronary artery). As the CHADS2 and CHA2 DS2 -VASc scores increased, the presence of CAD also increased (P < 0.001). The severity of CAD was correlated with CHADS2 score (Spearman coefficient 0.229, P < 0.001) and CHA2 DS2 -VASc score (Spearman coefficient 0.261, P < 0.001). In multivariate analysis, after adjusting for confounding factors, CHADS2 and CHA2 DS2 -VASc scores ≥2 were independently associated with CAD. The CHA2 DS2 -VASc score was a better predictor of the presence of CAD than the CHADS2 score on area under the curve analysis.

CONCLUSION

CHADS2 and CHA2 DS2 -VASc scores were predictive of the presence and severity of CAD in patients with stroke. When a patient has high CHADS2 or CHA2 DS2 -VASc scores, physicians should consider coronary artery evaluation.

cAMP response element binding protein H mediates fenofibrate-induced suppression of hepatic lipogenesis

AIMS/HYPOTHESIS

Fenofibrate is a drug used to treat hyperlipidaemia that works by inhibiting hepatic triacylglycerol synthesis. Sterol regulatory element binding protein-1c (SREBP-1c) is a major regulator of the expression of genes involved in hepatic triacylglycerol synthesis. In addition, endoplasmic reticulum (ER)-bound transcription factor families are involved in the control of various metabolic pathways. Here, we show a novel function for an ER-bound transcription factor, cAMP response element binding protein H (CREBH), in fenofibrate-mediated inhibition of hepatic lipogenesis.

METHODS

The effects of fenofibrate and adenovirus-mediated Crebh (also known as Creb313) overexpression (Ad-Crebh) on hepatic SREBP-1c production and lipogenesis in vitro and in vivo were investigated. We also examined whether downregulation of endogenous hepatic Crebh by small interfering (si)RNA restores the fenofibrate effect on hepatic lipogenesis and SREBP-1c production. Finally, we examined the mechanism by which CREBH inhibits hepatic SREBP-1c production.

RESULTS

Fasting and fenofibrate treatment induced CREBH production and decreased SREBP-1c levels. Indeed, Ad-Crebh inhibited insulin- and liver X receptor agonist TO901317-induced Srebp-1c (also known as Srebf1) mRNA expression in cultured hepatocytes. Moreover, increased production of CREBH in the liver of mice following tail-vein injection of Ad-Crebh inhibited high-fat diet-induced hepatic steatosis through inhibition of Srebp-1c expression. The inhibition of endogenous Crebh expression by siRNA restored fenofibrate-induced suppression of Srebp-1c expression and hepatic lipid accumulation both in vitro and in vivo.

CONCLUSIONS/INTERPRETATION

These results show that fenofibrate decreases hepatic lipid synthesis through induction of CREBH. This study suggests CREBH as a novel negative regulator of SREBP-1c production and hepatic lipogenesis.

Comparison of chest digital tomosynthesis and chest radiography for detection of asbestos-related pleuropulmonary disease

AIM

To compare chest digital tomosynthesis (DTS) with digital radiography for the detection of asbestos-related pleuropulmonary disease.

MATERIALS AND METHODS

The institutional review board approved this study and all participants gave informed consent. Forty-five participants with a history of asbestos exposure were examined with DTS and radiography. Low-dose multidetector computed tomography (CT) in the prone position served as the reference. Two observers evaluated all images for the presence of pleural abnormalities and asbestosis. Interobserver agreement was analysed by using the k statistic. Diagnostic performance of the two imaging methods was compared using McNemar's test.

RESULTS

Interobserver agreement regarding DTS findings was moderate to very good (k = 0.544-0.846) and superior to the radiographic findings (k = 0.236-1.000). Overall, the diagnostic accuracy of DTS for the lesion detection was significantly better than with radiography (all p < 0.05, except that for the comparison of diagnostic accuracy of DTS versus radiographic detection of left diaphragmatic plaques and asbestosis). DTS was more sensitive than radiography for the detection of asbestosis (82% versus 27%, p = 0.031).

CONCLUSION

DTS is more accurate than radiography in the detection of pleural plaques and more sensitive than radiography in the detection of asbestosis. Interobserver agreements with respect to the DTS findings were superior to the radiographic findings.

The frequency of cerebral microbleeds increases with CHADS(2) scores in stroke patients with non-valvular atrial fibrillation

BACKGROUND AND PURPOSE

Cerebral microbleeds (CMBs) are extravasations of blood from lipohyalinized or amyloid angiopathic cerebral arterioles, and the presence and numbers of CMBs are significantly associated with the development of oral anticoagulation (OA)-related intracranial haemorrhage (ICH). The aim of this study was to investigate whether there is a difference in CMBs burden according to CHADS(2) scores or CHA(2) DS(2) -VASc scores in non-valvular atrial fibrillation (NVAF) patients.

METHODS

We included 550 ischaemic stroke patients who had NVAF and who had undergone brain magnetic resonance imaging (MRI) with gradient-recalled echo (GRE) T2 sequences from our prospective stroke registry between January 2005 and November 2011. We calculated CHADS(2) scores and CHA(2) DS(2) -VASc scores for all patients based on their underlying cardiovascular diseases. The presence, location and number of CMBs were assessed in each patient. We also investigated whether the CMBs were actually associated with the development of ICH during follow-up.

RESULTS

The mean patient age was 70.4 ± 10.5 years, and 324 (58.9%) patients were men. One-hundred and seventy-three patients (31.5%) had CMBs detected on GRE MRI. Higher CHADS(2) scores or CHA(2) DS(2) -VASc scores were strongly associated with the presence and number of CMBs. During follow-up of median 3.1 ± 1.6 years, the presence of CMBs was independently associated with the development of ICH, whilst the CHADS(2) scores or CHA(2) DS(2) -VASc scores were not.

CONCLUSIONS

Considering the positive association between the presence of CMBs and OA-related ICH, our results suggest that the increase in ICH in high-risk groups during OA may be related to an increased burden of CMBs.

Proteins involved in DNA damage response pathways and survival of stage I non-small-cell lung cancer patients

BACKGROUND

Biological complexity leads to significant variation in the survival of patients with stage I non-small-cell lung cancer (NSCLC). DNA damage response (DDR) pathways play a critical role in maintaining genomic stability and in the progression of NSCLC. Therefore, the development of a prognostic biomarker focusing on DDR pathways is an intriguing issue.

PATIENTS AND METHODS

Expression of several proteins (ATM, ATMpS1981, γH2AX, 53BP1, 53BP1pS25, Chk2, Chk2pT68, MDC1, MDC1pS964, BRCA1pS1423, and ERCC1) and overall survival were investigated in 889 pathological stage I NSCLC patients.

RESULTS

Low expression of BRCA1pS1423 or ERCC1 was significantly associated with worse survival in the whole cohort of patients. Analysis performed based on histology revealed that low expression of γH2AX, Chk2pT68, or ERCC1 was a poor prognostic factor in squamous cell carcinoma patients [adjusted hazard ratio (aHR), Cox P: 1.544, 0.012 for γH2AX; 1.624, 0.010 for Chk2pT68; 1.569, 0.011 for ERCC1]. The analysis of the interaction between two proteins showed that this effect was more pronounced in squamous cell carcinoma patients. However, these effects were not detected in adenocarcinoma patients.

CONCLUSIONS

The proteins involved in DDR pathways exhibited differential expression between squamous cell carcinoma and adenocarcinoma and were important determinants of survival in stage I squamous cell carcinoma patients.

Observation of reactor electron antineutrinos disappearance in the RENO experiment

The RENO experiment has observed the disappearance of reactor electron antineutrinos, consistent with neutrino oscillations, with a significance of 4.9 standard deviations. Antineutrinos from six 2.8  GW(th) reactors at the Yonggwang Nuclear Power Plant in Korea, are detected by two identical detectors located at 294 and 1383 m, respectively, from the reactor array center. In the 229 d data-taking period between 11 August 2011 and 26 March 2012, the far (near) detector observed 17102 (154088) electron antineutrino candidate events with a background fraction of 5.5% (2.7%). The ratio of observed to expected numbers of antineutrinos in the far detector is 0.920±0.009(stat)±0.014(syst). From this deficit, we determine sin(2)2θ(13)=0.113±0.013(stat)±0.019(syst) based on a rate-only analysis.

New limits on interactions between weakly interacting massive particles and nucleons obtained with CsI(Tl) crystal detectors

New limits are presented on the cross section for weakly interacting massive particle (WIMP) nucleon scattering in the KIMS CsI(Tℓ) detector array at the Yangyang Underground Laboratory. The exposure used for these results is 24 524.3  kg·days. Nuclei recoiling from WIMP interactions are identified by a pulse shape discrimination method. A low energy background due to alpha emitters on the crystal surfaces is identified and taken into account in the analysis. The detected numbers of nuclear recoils are consistent with zero and 90% confidence level upper limits on the WIMP interaction rates are set for electron equivalent energies from 3 to 11 keV. The 90% upper limit of the nuclear recoil event rate for 3.6-5.8 keV corresponding to 2-4 keV in NaI(Tℓ) is 0.0098 counts/kg/keV/day, which is below the annual modulation amplitude reported by DAMA. This is incompatible with interpretations that enhance the modulation amplitude such as inelastic dark matter models. We establish the most stringent cross section limits on spin-dependent WIMP-proton elastic scattering for the WIMP masses greater than 20  GeV/c2.

Metformin ameliorates IL-6-induced hepatic insulin resistance via induction of orphan nuclear receptor small heterodimer partner (SHP) in mouse models

AIMS/HYPOTHESIS

IL-6 is a proinflammatory cytokine associated with the pathogenesis of hepatic diseases. Metformin is an anti-diabetic drug used for the treatment of type 2 diabetes, and orphan nuclear receptor small heterodimer partner (SHP, also known as NR0B2), a transcriptional co-repressor, plays an important role in maintaining metabolic homeostasis. Here, we demonstrate that metformin-mediated activation of AMP-activated protein kinase (AMPK) increases SHP protein production and regulates IL-6-induced hepatic insulin resistance.

METHODS

We investigated metformin-mediated SHP production improved insulin resistance through the regulation of an IL-6-dependent pathway (involving signal transducer and activator of transcription 3 [STAT3] and suppressor of cytokine signalling 3 [SOCS3]) in both Shp knockdown and Shp null mice.

RESULTS

IL-6-induced STAT3 transactivation and SOCS3 production were significantly repressed by metformin, adenoviral constitutively active AMPK (Ad-CA-AMPK), and adenoviral SHP (Ad-SHP), but not in Shp knockdown, or with the adenoviral dominant negative form of AMPK (Ad-DN-AMPK). Chromatin immunoprecipitation (ChIP), co-immunoprecipitation (Co-IP) and protein localisation studies showed that SHP inhibits DNA binding of STAT3 on the Socs3 gene promoter via interaction and colocalisation within the nucleus. Upregulation of inflammatory genes and downregulation of hepatic insulin signalling by acute IL-6 treatment were observed in wild-type mice but not in Shp null mice. Finally, chronic IL-6 exposure caused hepatic insulin resistance, leading to impaired insulin tolerance and elevated gluconeogenesis, and these phenomena were aggravated in Shp null mice.

CONCLUSIONS/INTERPRETATION

Our results demonstrate that SHP upregulation by metformin may prevent hepatic disorders by regulating the IL-6-dependent pathway, and that this pathway can help to ameliorate the pathogenesis of cytokine-mediated metabolic dysfunction.

Failure analysis of InGaN/GaN high power light-emitting diodes fabricated with ITO transparent p-type electrode during accelerated electro-thermal stress

We have investigated the high-temperature degradation of optical power as well as electrical properties of InGaN/GaN light-emitting diodes (LEDs) fabricated with ITO transparent p-electrode during accelerated electro-thermal stress. As the thermal stress increased from 150 degrees C to 250 degrees C at a electrical stress of 200 mA, the optical power of the LEDs was significantly reduced. Degradation of the optical power was thermally activated, with the activation of 0.9 eV. In addition, the activation energy of the degradation of optical power was fairly similar to that of the degradation of series resistance of the LEDs, 1.0 eV, which implies that the increase in the series resistance may result in the severe degradation of optical power. We also showed that the increase in the series resistance of the LEDs during the accelerated electro-thermal stress can be attributed to reduction of the active acceptor concentration in the p-type semiconductor layers and local joule heating due to the current crowding.

Alteration of ictal and interictal perfusion in patients with paroxysmal kinesigenic dyskinesia

Although previous cerebral blood flow studies have suggested that the basal ganglia or thalamus are involved in the pathogenesis of paroxysmal kinesigenic dyskinesia (PKD), the precise anatomic substrate or pathophysiological networks associated with PKD remain unclear. Here, ictal and interictal single photon emission computed tomography (SPECT) in 2 patients with idiopathic PKD compared to 6 age-matched normal controls and the perfusion findings of subtraction ictal SPECT co-registered to MRI (SISCOM) in 1 patient are reported. The interictal and ictal perfusion changes were different in each of the patients and there were no consistent anatomic substrates observed. 2 patients had significant perfusion changes in the left frontal/temporal cortices compared to controls, whereas the others showed an increased uptake of 99mTc-ethyl cysteinate dimer (ECD) in the left occipital area on subtraction SPECT imaging. The results of this study suggest that the pathophysiology of PKD cannot be simply explained by lesions of the basal ganglia or thalamus, and that other associated areas of the cortex are likely involved in these movement disorders.

Use of a handheld, computerized device as a decision support tool for stroke classification

BACKGROUND

The Trial of ORG 10172 in Acute Stroke Treatment (TOAST) classification has been widely used to determine etiology of ischemic stroke. However, interrater reliability is known to be modest. The complexity of abstraction and the interpretation of various clinical and laboratory data might limit the accuracy of the TOAST classification. In this study, we developed a computerized clinical decision support system for stroke classification that can be used in a handheld device and tested whether this system can improve diagnostic accuracy and reliability.

METHODS

Based on the TOAST classification, a logical algorithm was developed and implemented on a handheld device, named iTOAST. After answering six questions using the touch interface, the stroke subtype result is displayed on the screen. Four neurology residents were randomly assigned to classify stroke subtypes using iTOAST or the conventional method (cTOAST). Using a crossover design, they classified the stroke subtypes of 70 patients. The standard subtypes were determined by three stroke experts. Correlated kappa coefficients using iTOAST compared with cTOAST were determined.

RESULTS

The kappa (SE) value of iTOAST [0.790 (0.041), 95% CI: 0.707-0.870] was higher than that of cTOAST [0.692 (0.046), 95% CI: 0.600-0.782] (P<0.001). Neither sequence (P=0.857) nor period effect (P=0.999) was observed.

CONCLUSIONS

The stroke classification tool using a handheld, computerized device was easy, accurate, and reliable over the conventional method. It may have additional benefit because a handheld, computerized device is accessible anytime and anywhere.

Early neurological outcomes according to CHADS2 score in stroke patients with non-valvular atrial fibrillation

BACKGROUND AND PURPOSE

A higher CHADS(2) score or CHA(2)DS(2)-VASc score is associated with an increased risk of ischaemic stroke in patients with non-valvular atrial fibrillation (NVAF). However, there are no data regarding early neurological outcomes after stroke according to the risk levels.

METHODS

In this study, a total of 649 stroke patients with NVAF were enrolled and categorized into three groups: low-risk (CHADS(2) score of 0-1), moderate-risk (CHADS(2) score 2-3), or high-risk group (CHADS(2) score ≥4). CHA(2)DS(2)-VASc score was divided into four groups including 0-1, 2-3, 4-5, and ≥6. We investigated whether there were differences in initial stroke severity, early neurological outcome, and infarct size according to CHADS(2) score or CHA(2)DS(2)-VASc score in stroke patients with NVAF.

RESULTS

The initial National Institutes of Health Stroke Scale (NIHSS) score was highest in high-risk group [9.5, interquartile range (IQR) 4-18], followed by moderate-risk (8, IQR 2-17) and low-risk group (6, IQR 2-15) (P=0.012). Likewise, initial stroke severity increased in a positive fashion with increasing the CHA(2)DS(2)-VASc score. During hospitalization, those in the high-risk group or higher CHA(2)DS(2)-VASc score had less improvement in their NIHSS score. Furthermore, early neurological deterioration (END) developed more frequently as CHADS(2) score or CHA(2)DS(2)-VASc score increased. Multivariate analysis showed being in the high-risk group was independently associated with END (OR 2.129, 95% CI 1.013-4.477).

CONCLUSIONS

Our data indicate that patients with NVAF and higher CHADS(2) score or CHA(2)DS(2)-VASc score are more likely to develop severe stroke and a worse clinical course is expected in these patients after stroke presentation.

Prediction of survival and cancer recurrence using F-18 FDG PET/CT in patients with surgically resected early stage (Stage I and II) non-small cell lung cancer

The aim of the current study was to investigate the prognostic value of SUV(max) in patients with completely resected early stage (stage I and II) NSCLC. A retrospective review identified 76 patients with surgically resected early (stage I and II) NSCLC who received F-18 FDG PET/CT at diagnosis of cancer. Survival analysis was conducted using Kaplan-Meier analysis, and survival curves stratified by age, sex, mediastinal lymph node involvement, SUV(max), and TNM staging were generated for estimation of overall survival and disease free survival (DFS). Independent predictive factors for survival were determined using Cox proportional hazard model. For overall survival, the median survival of the patients with tumor SUV(max)≤ 6.7 was 48.9 months and was significantly longer than the patients with tumor SUV(max)>6.7 (Log rank test, Χ²=18.01, p5.9. The median survival of the patients with tumor SUV(max)≤ 5.9 was 31.7 months (Log rank test, Χ²=16, p=0.0001). In conclusion, high FDG uptake measured by F-18 FDG PET/CT might have a prognostic value for overall survival and DFS in surgically resected early stage (stage I and II) NSCLC even after stratified by pathologic stages.

Analysis of 2D periodic nanostructures with an oxide overlayer via spectroscopic ellipsometry

The accurate nondestructive determination of the shapes or critical dimensions of periodic nanostructures is essential to the current integrated-circuits technology. Optical critical dimension (OCD) metrology is fast, nondestructive, and can be used in air, allows higher sampling rates compared to the non-optical methods such as scanning electron microscopy (SEM) or atomic-force microscopy (AFM), and does not damage the sample. The data are typically analyzed via rigorous coupled-wave analysis (RCWA), where the sample is modeled as a series of layers whose dimensional parameters are determined by a least-squares fit. The layers are typically approximated as a combination of core material and ambient. Oxide overlayers and surface roughness are common, however, and call into question two-phase approximation. In this study, a structure that is periodic in two dimensions and that is coated with a thin (3 nm) oxide was studied, and an extension of the RCWA method that allows structural information to be extracted from optical data even in the presence of oxide overlayers or surface roughness was developed.

Effects of low-level arsenic exposure on urinary N-acetyl-β-D-glucosaminidase activity

This study was aimed to evaluate whether renal tubular function is impaired by exposure to relatively low concentrations of arsenic. Mean urinary arsenic concentrations and N-acetyl-β-D-glucosaminidase (NAG) activities were compared among 365 and 502 Korean men and women, respectively, in relation to gender, smoking, alcohol consumption, and recent seafood consumption. The study subjects were divided into 4 groups according to urinary NAG activity and seafood consumption prior to urine sampling, and the correlation between arsenic concentration and urinary NAG activity was tested for each group. The mean urinary arsenic level was higher in women, non-smokers, and non-drinkers in comparison to men, smokers, and drinkers, respectively. Individuals who consumed seafood within 3 days prior to urine sampling showed a higher mean urinary arsenic level than those who did not. The correlation between urinary arsenic concentration and NAG activity in urine was significant only in subjects who did not consume seafood within 3 days prior to urine sampling and whose urinary NAG activity was 7.44 U/g creatinine (75th percentile) or higher. The urinary arsenic concentration was a significant determinant of urinary NAG activity in subjects with NAG activity higher than 7.44 U/g creatinine and especially in those who had not consumed seafood recently. These facts suggest that a relatively low-level exposure to inorganic arsenic produces renal tubular damage in humans.

Patient with positional wheezing due to endobronchial lipomatous hamartoma

Endobronchial hamartoma is a rare form of pulmonary hamartoma, and endobronchial lipomatous hamartomas are even rarer. We describe the case of a 39-year-old man who presented with a two-year history of dyspnea on exertion and wheezing over the left chest only while lying on his left side. The patient was diagnosed with endobronchial lipomatous hamartoma occluding the left main bronchus. He underwent a superior segmentectomy of the left lower lobe, which promptly relieved the dyspnea and positional wheezing. To our knowledge, fewer than 10 such cases are cited in the English literature, none of which presented with positional wheezing. This patient represents the first case of focal and positional wheezing resulting from endobronchial lipomatous hamartoma.

Subconjunctival fat prolapse and dermolipoma of the orbit: differentiation on CT and MR imaging

BACKGROUND AND PURPOSE

Subconjunctival fat prolapse and dermolipoma of the orbit are unfamiliar to radiologists and yet should be differentiated because their treatments are different. The purpose of this study was to investigate the CT and MR imaging findings that distinguish these 2 conditions.

MATERIALS AND METHODS

Between 1995 and 2009, we found 33 patients (27 men, 6 women; mean age, 63 years) with surgically proved subconjunctival fat prolapse and 27 patients (3 males, 24 females; mean age, 17 years) with dermolipoma in our hospital. Among them, 8 patients with subconjunctival fat prolapse and 6 patients with dermolipoma underwent CT and/or MR imaging examinations. We retrospectively reviewed CT scans and MR images in these patients.

RESULTS

In all of the 8 patients with subconjunctival fat prolapse, CT and MR images demonstrated the herniated fat at the superotemporal epibulbar area, continuous with the intraconal fat, extending forward between the lateral wall of the globe medially and the lateral rectus muscle and the lacrimal gland laterally, either bilaterally (n = 7) or unilaterally (n = 1). In contrast, all 6 patients with dermolipoma had a unilateral, crescent- (n = 5), or triangle-shaped (n = 1) fatty mass at the temporal or superotemporal epibulbar area, which lay on the lateral wall of the globe, anterior to the insertion of the lateral rectus muscle and medial to the lacrimal gland, without connection to the intraconal fat.

CONCLUSIONS

The characteristic CT and MR imaging findings may help easily differentiate subconjunctival fat prolapse and dermolipoma, both of which usually present as an epibulbar fatty mass in the lateral canthal area.

Effect of warfarin withdrawal on thrombolytic treatment in patients with ischaemic stroke

BACKGROUND AND PURPOSE

  Abruptly discontinuing warfarin may induce a rebound prothrombotic state. Thrombolytic agents may also paradoxically induce prothrombotic conditions, which include platelet activation and thrombin generation. Therefore, prothrombotic states may be enhanced by withdrawing warfarin in patients under thrombolytic treatment. This study was aimed to determine whether patients with warfarin withdrawal have different clinical outcomes from those without warfarin use after thrombolytic treatment.

METHODS

  A total of 148 consecutive patients with atrial fibrillation who were not on anticoagulants at admission and who received thrombolysis were included in this study. We compared the outcomes between a warfarin withdrawal group and a no-warfarin group.

RESULTS

  Fourteen patients (9.5%) were included in the warfarin withdrawal group. Although baseline National Institute of Health Stroke Scale (NIHSS) scores, recanalization rates, and hemorrhage frequencies did not differ between the groups, the warfarin withdrawal group showed poorer outcomes. Increased NIHSS scores during the first 7days were more frequent in the warfarin withdrawal group (57.1% vs. 26.9%, P=0.029). The median percent improvement in NIHSS scores at 24h after thrombolysis was also lower in the warfarin withdrawal group. After adjusting for covariates, warfarin withdrawal was a strong predictor of poor functional outcome at 3months (modified Rankin score≥3) (odds ratio, 17.067, 95% CI 2.703-107.748).

CONCLUSIONS

  Discontinuing warfarin was associated with early neurologic deterioration and poor long-term outcomes after thrombolytic treatment.

Failure of complete recanalization is associated with poor outcome after cardioembolic stroke

BACKGROUND

  Recanalization is strongly associated with outcomes after thrombolytic treatment. Cardiac emboli are known as better response to fibrinolytic agents because they are fibrin-rich; however, cardioembolic stroke itself is associated with poor outcomes and high mortality. Completeness of recanalization may therefore affect the outcome of cardioembolic stroke. We investigated whether degree of recanalization influences outcomes following fibrinolytic therapy in cardioembolic stroke.

METHODS

  Consecutive stroke patients with relevant artery occlusions on baseline CT angiography who had received thrombolytic treatment were enrolled. Completeness of recanalization was assessed by the Thrombolysis in Myocardial Infarction (TIMI) grade, which was compared between patients with and without cardiac sources of embolism (CSE). We also investigated independent predictors of poor outcome (modified Rankin scale score 3-6) at 3 months.

RESULTS

  Of the 127 patients enrolled, 65 (51%) had one or more CSE. Although the overall recanalization rates (TIMI 2 or 3) in patients with CSE (65%) and patients without CSE (68%) were similar (P=0.710), patients with CSE were less likely to show complete recanalization (TIMI 3) compared with those without CSE (19% vs. 39%, P=0.011). Multivariate analysis revealed that CSE was associated with failure of complete recanalization (OR 2.809, 95% CI 1.097-7.192) and was an independent predictor of poor outcome at 3months (OR 3.629, 95% CI 1.205-8.869).

CONCLUSIONS

  In cardioembolic strokes, failure of complete recanalization following thrombolytic therapy was frequent and was associated with poor outcome after thrombolysis.