Search

High-entropy alloys (HEAs) provide new research avenues for alloy combinations in the periodic table, opening numerous possibilities in novel-alloy applications. However, their electrical characteristics have been relatively underexplored. The challenge in establishing an HEA electrical conductivity model lies in the changes in electronic characteristics caused by lattice distortion and complexity of nanostructures. Here we show a low-frequency electrical conductivity model for the Nb-Mo-Ta-W HEA system. The cocktail effect is found to explain trends in electrical-conductivity changes in HEAs, while the magnitude of the reduction is understood by the calculated plasma frequency, free electron density, and measured relaxation time by terahertz spectroscopy. As a result, the refractory HEA Nb 15 Mo 35 Ta 15 W 35 thin film exhibits both high hardness and excellent conductivity. This combination of Nb 15 Mo 35 Ta 15 W 35 makes it suitable for applications in atomic force microscopy probe coating, significantly improving their wear resistance and atomic-scale image resolution., (© 2024. The Author(s).)

Due to extraordinary electronic and optoelectronic properties, large-scale single-crystal two-dimensional (2D) semiconducting transition metal dichalcogenide (TMD) monolayers have gained significant interest in the development of profit-making cutting-edge nano and atomic-scale devices. To explore the remarkable properties of single-crystal 2D monolayers, many strategies are proposed to achieve ultra-thin functional devices. Despite substantial attempts, the controllable growth of high-quality single-crystal 2D monolayer still needs to be improved. The quality of the 2D monolayer strongly depends on the underlying substrates primarily responsible for the formation of grain boundaries during the growth process. To restrain the grain boundaries, the epitaxial growth process plays a crucial role and becomes ideal if an appropriate single crystal substrate is selected. Therefore, this perspective focuses on the latest advances in the growth of large-scale single-crystal 2D TMD monolayers in the light of enhancing their industrial applicability. In the end, recent progress and challenges of 2D TMD materials for various potential applications are highlighted., (© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Background: The present meta-analysis aims to investigate the effectiveness of heparin administration in suppressing physiological myocardial 18 F-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET)/computed tomography (CT), as its role in this regard has not been well investigated., Methods: PRISMA guidelines were used to interrogate the PubMed, Embase, Cochrane library, Web of Knowledge, and www.clinicaltrail.gov databases from the earliest records to March 2023. The final analysis included five randomized controlled trials (RCTs). Meta-analysis was conducted to compare the effectiveness of unfractionated heparin (UFH) administration versus non-UFH administration, and subgroup analysis based on fixed and variable fasting durations was conducted. Effect sizes were pooled using a random-effects model, and the pooled odds ratios (ORs) were calculated., Results: Five eligible RCTs with a total of 910 patients (550 with heparin, 360 without heparin) were included. The forest plot analysis initially indicated no significant difference in the suppression of myocardial FDG uptake between the UFH and non-UFH groups (OR 2.279, 95% CI 0.593 to  8.755, p = 0.23), with a high degree of statistical heterogeneity (I 2  = 91.16%). Further subgroup analysis showed that the fixed fasting duration group with UFH administration had statistically significant suppression of myocardial FDG uptake (OR 4.452, 95% CI 1.221 to 16.233, p = 0.024), while the varying fasting duration group did not show a significant effect., Conclusions: According to the findings of our meta-analysis, we suggest that intravenous administration of UFH can be considered as a supplementary approach to suppress myocardial FDG uptake., (© 2023. The Author(s) under exclusive licence to American Society of Nuclear Cardiology.)

Background and Objectives : Treatment for antineutrophil cytoplasmic antibody-associated vasculitis (AAV) must deal with immunosuppression, as well as infections associated with a compromised immune system, such as tuberculosis (TB). Our aim was to examine the risk of incidental TB after diagnosis of AAV. Materials and Methods : This retrospective population-based cohort study was based on the data from the National Health Insurance Research Database in Taiwan. Patients with newly diagnosed granulomatous polyangiitis or microscopic polyangiitis were identified between 1 January 2000 and 31 December 2012. The primary outcome was risk of incidental TB. Cox proportional hazard models were used to evaluate the association between AAV and incidental TB. Results : A total of 2257 patients with AAV and a propensity-score matched cohort of 9028 patients were studied. Overall, patients with AAV were at a 1.48× higher risk of contracting incidental TB than the patients in the matched cohort (adjusted HR 1.48; 95% confidence interval [CI], 1.02-2.15). Note that the highest risk of contracting incidental TB was in the first two years following a diagnosis of AAV, with a nearly 1-fold increase in risk (adjusted HR, 1.91; 95% CI, 1.01-3.60). Female AAV patients were 3.24× more likely than females without AAV to develop TB (adjusted HR 3.24; 95% CI, 1.85-5.67). Conclusions : Patients with AAV exhibit a 48% elevated TB risk, notably, a 91% increase within the first two years postdiagnosis. Female AAV patients face a 3.24 times higher TB risk compared to females without AAV. This study is limited by potential misclassification and overestimation of AAV cases. Clinicians should closely monitor TB risk in AAV patients, especially in females and the initial two years following diagnosis.

Extrastriatal accumulation on technetium-99m-([2-[[2-[[[3-(4-chlorophenyl)-8-methyl-8-azabicyclo[3,2,1]oct-2-yl]methyl](2-mercaptoethyl)amino]ethyl]amino]- ethanethiolato(3-)-N2,N2',S2,S2']oxo-[1R-(exo-exo)])( 99m Tc)-TRODAT-1 is unexpected during nuclear medicine nigrostriatal pathway examinations on 99m Tc-TRODAT-1 brain single photon emission computed tomography (SPECT). An 86-year-old female with a history of right hemiparesis, speech expressive difficulties, unstable gait, and bradykinesia on right side was reported. Technetium-99m -TRODAT-1 dopamine transporter SPECT revealed an incidental extrastriatal accumulation of radiotracer in the left anterior frontal region, accompanied by a photopenic area which resulted in the displacement of the left striatum with decreased dopaminergic neuronal function. The brain magnetic resonance imaging (MRI) revealed an invasive meningioma corresponding to the extrastriatal uptake on SPECT, accompanied by edema and mass effect. The patient received surgery and the histopathological results confirmed the diagnosis of atypical meningioma.This study emphasizes the importance of understanding the underlying causes of extrastriatal uptake from 99m Tc-TRODAT-1 brain SPECT, which may indicate an invasive brain tumor.

Intracellular purine- and pyrimidine-related derivatives are vital molecules for preserving genetic information and are essential for cellular bioenergetics and signal transduction. This study developed a practical liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for quantifying intracellular purine- and pyrimidine-related derivatives. To solve the distorted peak shape related to di- and triphosphate nucleotides, in-sample addition of medronic acid and ammonium phosphate was performed. Using the BEH-amide column, the results showed that adding 0.5 mM medronic acid to the sample significantly improved the peak shape without causing an obvious ion suppressive effect. Method validation confirmed that the coefficients of determination ( R 2 ) values for linearity evaluation were above 0.94 for all analytes. The intraday and interday accuracies ranged from 85.1 to 128.4%, with the precision below 16.6%. The validated method was successfully applied in characterizing the alterations of purine- and pyrimidine-related derivatives in the A549 cell line with perturbed mitochondrial fission or blockade of the electron transport chain. Collectively, this study demonstrates that the strategy of in-sample medronic acid addition is effective in improving the quantification of intracellular purine- and pyrimidine-related derivatives. We believe that our proposed platform can facilitate the development of novel drugs targeting purine and pyrimidine metabolism in the future.

In this study, we have designed an electrically tunable multi-band terahertz (THz) metamaterial filter based on graphene and multiple-square-loop structures. The structure contains multiple metal square loops, and these loops with different sizes correspond to different THz frequencies, achieving our expected efficacy of a multiband wave filter. Furthermore, by sweeping external voltages, we could change graphene's Fermi levels, and thus the high-sensitivity THz filter's capability from single-band to multi-band filtering can be modulated. We expect that this study of a hybrid THz wave filter would be promising for the development of selecting channels in THz and 6 G communications.

Purpose: Wearing a mask during the coronavirus disease 2019 epidemic (COVID-19) is a preventive way to reduce droplet and aerosol transmission. The purpose of this study was to evaluate the position error of wearing a surgical mask during radiotherapy in head and neck cancer patients., Patients and Methods: We collected and analyzed 2351 kV X-ray image records of 81 patients with head and neck cancer who underwent image-guided radiotherapy (IGRT). Patients with/without a surgical mask were divided into the head-neck (HN) mask group and head-neck-shoulder (HNS) mask group. The position error in the X (left-right), Y (superior-inferior), Z (anterior-posterior), 3D (three dimensional) vectors, as well as the pitch and yaw axes were compared between the four groups., Results: We found that patients wearing surgical masks in the HN mask group showed no significant differences in the mean position error of the different types of headrest (p>0.05). In the HNS mask group, only the type C headrest group showed significant differences (P < 0.05). The X axis values were -0.05±0.07 and -0.11± 0.01 cm (P = 0.04), and the pitch axis values were 0.34±0.29° and 0.83±0.08° (P = 0.01)., Conclusion: The mean position error of most patients wearing surgical masks was not greater than patients without a surgical mask. Patients wearing while receiving treatment is a low-cost and easy-to-implement prevention method., Competing Interests: The authors report no conflicts of interest in this work., (© 2022 Chan et al.)

Objective: Visceral obesity, assessed using the visceral adiposity index (VAI), is related to mortality, but studies of populations with chronic kidney disease (CKD) are scarce. The aim of this study was to evaluate the relationship between VAI and all-cause mortality among individuals with CKD., Methods: We retrospectively explored the relationship between VAI and risk for all-cause death by analyzing the data of 4145 patients with CKD who participated in the National Health and Nutrition Examination Survey (NHANES) 2001-2006. Patients were followed until December 31, 2015., Results: After an average follow-up of 134.14 mo, 1034 (24.95%) deaths were recorded. Comparison of VAI quartiles with the reference showed an unstable association of VAI with all-cause mortality after adjusting for a wide range of potential confounders in Cox regression analysis. The correlation between VAI and mortality was J-shaped after applying the penalized spline method. Before the inflection point (VAI = 68.23), higher VAI had a protective effect against mortality (hazard ratio [HR], 0.47; 95% confidence interval [CI], 0.28-0.77). However, the risk for all-cause mortality gradually increased with the VAI (HR, 1.13; 95% CI, 1.05-1.21)., Conclusion: Visceral obesity may influence the rate of all-cause mortality in a nonlinear manner in populations with CKD. Risk for death was higher with visceral fat deficiency than with excessive visceral fat deposition., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Diet property grounded on inflammatory potential, evaluated by the dietary inflammatory index (DII), has been proven to be connected with mortality, while studies of adults with chronic kidney disease (CKD) are scarce., Objective: The purpose of this research was to evaluate the interrelationships between DII and all-cause mortality among adults with CKD., Methods: In the National Health and Nutrition Examination Survey (NHANES) 2001-2006, we identified and evaluated data of 4,554 adults with CKD. DII scores were calculated from 24 h of dietary consumption at baseline. Vital status was followed through 31 December 2015. The association of all-cause mortality with DII score was assessed using the Kaplan-Meier curve and the Cox regression analysis., Results: After an average follow-up of 132.103 months, a total of 1,246 (27.36%) deaths were recorded. The death rates in the DII tertile categories were 24.04, 26.81, and 31.23%, respectively. The Kaplan-Meier curve showed increased death risks for the high DII tertile as compared with the low DII tertile. After we adjusted for a broad range of possible confounders, the estimation between extreme tertiles of DII scores presented a positive and significant association with all-cause mortality [hazard ratio ( HR ): 1.21, 95% CI : 1.05-1.39]., Conclusion: Our results confirm the hypothesis that proinflammatory diets contribute to the increased all-cause mortality in adults with CKD., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yan, Zhang, Ma and Zheng.)

Recently, nanoscale light manipulation using surface plasmon polaritons (SPPs) has received considerable research attention. The conventional method of detecting SPPs is through light scattering or using bulky Si or Ge photodetectors. However, these bulky systems limit the application of nanophotonic circuits. In this study, the light-matter interaction between graphene and SPP was investigated. For realizing an improved integration in nanocircuits, single-layer graphene was added to asymmetric SPP nanoantenna arrays for nonscattering detection in the near field. The developed device is capable of detecting the controlled propagation of SPPs with a photoresponsivity of 15 mA/W, which paves the way for the new-generation on-chip optical communication.

The development of optical organic nanoparticles (NPs) is desirable and widely studied. However, most organic dyes are water-insoluble such that the derivatization and modification of these dyes are difficult. Herein, we demonstrated a simple platform for the fabrication of organic NPs designed with emissive properties by loading ten different organic dyes (molar masses of 479.1-1081.7 g/mol) into water-soluble polymer nanosponges composed of poly(styrene-alt-maleic acid) (PSMA). The result showed a substantial improvement over the loading of commercial dyes (3.7-50% loading) while preventing their spontaneous aggregation in aqueous solutions. This packaging strategy includes our newly synthesized organic dyes (> 85% loading) designed for OPVs (242), DSSCs (YI-1, YI-3, YI-8), and OLEDs (ADF-1-3, and DTDPTID) applications. These low-cytotoxicity organic NPs exhibited tunable fluorescence from visible to near-infrared (NIR) emission for cellular imaging and biological tracking in vivo. Moreover, PSMA NPs loaded with designed NIR-dyes were fabricated, and photodynamic therapy with these dye-loaded PSMA NPs for the photolysis of cancer cells was achieved when coupled with 808 nm laser excitation. Indeed, our work demonstrates a facile approach for increasing the biocompatibility and stability of organic dyes by loading them into water-soluble polymer-based carriers, providing a new perspective of organic optoelectronic materials in biomedical theranostic applications., (© 2022. The Author(s).)

Borophene (B), with remarkably unique chemical binding in its crystallographic structural phases including anisotropic structures, theoretically has high Young's modulus and thermal conductivity. Moreover, it is metallic in nature, and has recently joined the family of two-dimensional (2D) materials and is poised to be employed in flexible hetero-layered devices and sensors in fast electronic gadgets and excitonic devices. Interfacial coupling helps individual atomic sheets synergistically work in tandem, and is very crucial in controllable functionality. Most of the microscopic and spectroscopic scans reveal surface information; however, information regarding interfacial coupling is difficult to obtain. Electronic signatures of dynamic inter-layer coupling in B/boron nitride (BN) and B/molybdenum disulfide (MoS 2 ) have been detected in the form of distinct peaks in differential current signals obtained from scanning tunneling spectroscopy (STS) and conducting atomic force microscopy (CAFM). These unique sets of observed peaks represent interfacial coupling quantum states. The peaks in the electronic density of states (DOS) obtained via density functional theory (DFT) band structure calculations matched well with the electronic signatures of coupling quantum states. In our calculations, we found that the DOS peak evolves when the component layers are brought to compromised distances. While B/BN exhibits green sensitivity indicating mid-gap formation, B/MoS 2 bestows red sensitivity indicating band-gap excitation of MoS 2 . Molecular detection of methylene blue (MB) based on surface-enhanced Raman spectroscopy (SERS) was carried out with borophene-based hetero-layered stacks as molecular anchoring platforms.

Background: The coexistence of sarcopenia and dementia in aging populations is not uncommon, and they may share common risk factors and pathophysiological pathways. This study aimed to evaluate the relationship between brain atrophy and low lean mass in the elderly with impaired cognitive function., Methods: This cross-sectional study included 168 elderly patients who visited the multi-disciplinary dementia outpatient clinic at Kaohsiung Chang Gung Memorial Hospital for memory issues, between 2017 and 2019. The body composition was assessed by dual energy X-ray absorptiometry (DEXA) and CT based skeletal muscle index including L3 skeletal muscle index (L3SMI) and masseter muscle mass index (MSMI). The brain atrophy assessment was measured by CT based visual rating scale. Possible predictors of low lean mass in the elderly with cognitive impairement were identified by binary logistic regression. ROC curves were generated from binary logistic regression., Results: Among the 81 participants, 43 (53%) remained at a normal appendicular skeletal muscle index (ASMI), whereas 38 (47%) showed low ASMI. Compared with the normal ASMI group, subjects with low ASMI exhibited significantly lower BMI, L3SMI, and MSMI (all p < 0.05), and showed significant brain atrophy as assessed by visual rating scale (p < 0.001). The accuracy of predictive models for low ASMI in the elderly with cognitive impairment were 0.875, (Area under curve (AUC) = 0.926, 95% confidence interval [CI] 0.844-0.972) in model 1 (combination of BMI, GCA and L3SMI) and 0.885, (Area under curve (AUC) = 0.931, [CI] 0.857-0.979) in model 2 (combination of BMI, GCA and MSMI)., Conclusions: Global cortical atrophy and body mass index combined with either L3 skeletal muscle index or masseter skeletal muscle index can predict low lean mass in the elderly with cognitive impairment., (© 2021. The Author(s).)

Objective: To evaluate the association between radiation exposure from repeated nuclear medicine (NM) examinations and the subsequent risk of neoplasm in pediatric patients. Methods: From 2000 to 2017, participants under 18 years of age who underwent NM scanning were identified using the Health and Welfare Data Science Center (HWDC) dataset, which was extracted from the Taiwan National Health Insurance Research Database (NHIRD). Both the exposed cohort and unexposed subjects were followed up with until the presence of any malignancy arose, including malignant brain, lymphoid and hematopoietic tumors and benign brain or other central nervous tumors. Results: There were 35,292 patients in the exposed cohort and 141,152 matched subjects in the non-exposed group. The exposed cohort had an overall higher IR (IR: incidence rate, per 100,000 person-years) of any malignancy and benign central nervous tumor than the non-exposed group [IR, 16.9 vs. 1.54; adjusted hazard ratio (HR), 10.9; 95% CI, 6.53-18.2]. Further stratifying the number of NM examinations into 1-2, 3-4, and 5 or more times revealed that the IR of pediatric neoplasms increased gradually with the increased frequency of NM examinations (IR, 11.5; adjusted HR, 7.5; 95% CI, 4.29-13.1; IR, 25.8; adjusted HR, 15.9; 95% CI, 7.00-36.1; IR, 93.8; adjusted HR, 56.4; 95% CI, 28.8-110.3). Conclusion: NM examination is significantly associated with a higher risk of pediatric neoplasms, according to our population-based data. Thorough radiation protection and dose reduction in pediatric NM procedures should be an issue of concern., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Yuan, Chang, Yuan, Foo, Chan, Wang, Lin, Hsu and Kao.)

Background: Oxidative stress has been implicated in the pathogenesis of many diseases, including Parkinson's disease. Large protein aggregates may be produced after the breakdown of the proteostasis network due to overt oxidative stress. Meanwhile, brain volume loss and neuropsychiatric deficits are common comorbidities in Parkinson's disease patients. In this study, we applied a mediation model to determine the potential influences of oxidative stress-related plasma abnormal protein aggregate levels on brain volume and neuropsychiatric consequences in Parkinson's disease., Method: 31 patients with PD and 24 healthy controls participated in this study. The PD patients were further grouped according to the presentation of cognitive decline or not. All participants received complete examinations to determine plasma abnormal protein aggregates levels, brain volume, and neuropsychiatric performance. The results were collected and analyzed in a single-level three-variable mediation model., Results: Patients with PD cognitive decline exhibited higher plasma NfL levels, decreased regional brain volume, and poor neuropsychiatric subtest results compared with PD patients with normal cognition, with several correlations among these clinical presentations. The mediation model showed that the superior temporal gyrus completely mediated the effects of elevated plasma NfL levels due to the poor psychiatric performance of picture completion and digit span., Conclusion: This study provides insight into the effects of oxidative stress-related plasma abnormal protein aggregate levels on regional brain volume and neuropsychiatric consequences in Parkinson's disease patients., Competing Interests: The authors declare no conflict of interest concerning the research related to the manuscript., (Copyright © 2021 Pei-Chin Chen et al.)

Background and Objectives : To evaluate the effectiveness of hepatic arterial infusion chemotherapy (HAIC) followed by lipiodol infusion in advanced hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT). Materials and Methods : Thirty-two patients with advanced HCC and PVTT who received HAIC with regimens of cisplatin, mitomycin-C, and 5-fluorouracil followed by lipiodol infusion were enrolled. The primary efficacy endpoint was tumor response rate. The modified Response Evaluation Criteria in Solid Tumors (mRECIST) was used for assessment of treatment response. The secondary endpoints were overall survival (OS) and progression free survival (PFS). Prognostic factors for survival also were evaluated. Results : The median OS and PFS were 11.9 and 9.5 months, respectively. Seventeen patients (53.1%) achieved objective response, and 23 patients (71.9%) achieved disease control. The length of survival in the responder and disease control groups was longer than in the non-responder and progressive disease groups after two cycles of HAIC (responder vs. non-responder: 16.5 vs. 7.9 months, p = 0.001; disease control vs. progressive disease: 12.3 vs. 5.6 months, p < 0.001) and after completing HAIC (responder vs. non-responder: 15.7 vs. 6.9 months, p = 0.001; disease control vs. progressive disease: 13.6 vs. 6.9 months, p < 0.001). Better survival was associated with Child-Pugh A liver function ( p = 0.013), with early response to two HAIC cycles ( p = 0.009), and with response ( p = 0.02) and disease control ( p = 0.001) after completing HAIC treatment. Conclusion: HAIC followed by lipiodol infusion is a safe and feasible treatment for advanced HCC with PVTT. Patients with early response could continue HAIC treatment with expected prolonged survival.

Twisted light carries a well-defined orbital angular momentum (OAM) of l ℏ per photon. The quantum number l of its OAM can be arbitrarily set, making it an excellent light source to realize high-dimensional quantum entanglement and ultrawide bandwidth optical communication structures. In spite of its interesting properties, twisted light interaction with solid state materials, particularly two-dimensional materials, is yet to be extensively studied via experiments. In this work, photoluminescence (PL) spectroscopy studies of monolayer molybdenum disulfide (MoS 2 ), a material with ultrastrong light-matter interaction due to reduced dimensionality, are carried out under photoexcitation of twisted light. It is observed that the measured spectral peak energy increases for every increment of l of the incident light. The nonlinear l -dependence of the spectral blue shifts is well accounted for by the analysis and computational simulation of this work. More excitingly, the twisted light excitation revealed the unusual lightlike exciton band dispersion of valley excitons in monolayer transition metal dichalcogenides. This linear exciton band dispersion is predicted by previous theoretical studies and evidenced via this work's experimental setup.

Background: Whitefly Bemisia tabaci is a phloem-feeding insect and causes extensive agricultural damage around the world. Although the parasitic wasp Encarsia formosa is widely used to control B. tabaci on glasshouse tomatoes, low efficiency and discontinuity are frequently recorded. It has been well-documented that herbivore-induced plant volatiles (HIPVs) are important cues in the foraging behavior of the natural enemies of herbivores. However, the volatiles emitted from tomatoes infested by different developmental stages of B. tabaci (nymphs versus adults) have not been compared in terms of their effects on E. formosa attraction., Results: Olfactometer assays with four tomato cultivars revealed that the E. formosa wasps showed a significant attraction to the volatiles from adult-infested plants (except for cv. Castlemart), but not to those from nymph-infested plants. In a close-range habitat, however, the wasps appeared to use visual or tactile cues derived from nymphs for host location. Volatile analyses and behavioral assays showed that wasp attraction was correlated with enhanced β-myrcene and β-caryophyllene emissions from adult-infested plants. Furthermore, the use of B. tabaci adult-induced plant cues under glasshouse conditions resulted in a higher parasitism rate by this parasitoid., Conclusion: Our findings confirm that E. formosa uses the HIPVs resulting from feeding of B. tabaci adults to locate host habitat. Release of β-myrcene and β-caryophyllene from dispensers may enhance the efficacy of E. formosa as a biological control agent against B. tabaci in glasshouse production systems., (© 2020 Society of Chemical Industry.)

Purpose: Maintaining immobilization to minimize spine motion is very important during salvage stereotactic ablative radiation therapy (SABR) for recurrent head and neck cancer. This study aimed to compare the intrafractional motion between two immobilization methods., Patients and Methods: With a spine tracking system for image guiding, 9094 records from 41 patients receiving SABR by CyberKnife were obtained for retrospective comparison. Twenty-one patients were immobilized with a thermoplastic mask and headrest (Group A), and another 20 patients used a thermoplastic mask and headrest together with a vacuum bag to support the head and neck area (Group B). The intrafractional motion in the X (superior-inferior), Y (right-left), Z (anterior-posterior) axes, 3D (three-dimensional) vector, Roll, Pitch and Yaw in the two groups was compared. The margins of the planning target volume (PTV) to cover 95% intrafractional motion were evaluated., Results: The translational movements in the X-axis, Y-axis, and 3D vector in Group A were significantly smaller than in Group B. The rotational errors in the Roll and Yaw in Group A were also significantly smaller than those in Group B; conversely, those in the Pitch in Group A were larger. To cover 95% intrafractional motion, margins of 0.96, 1.55, and 1.51 mm in the X, Y and Z axes, respectively were needed in Group A, and 1.06, 2.86, and 1.34 mm, respectively were required in Group B., Conclusion: The immobilization method of thermoplastic mask and head rest with vacuum bag did not provide better immobilization than that without vacuum bag in most axes. The clinical use of 2 mm as a margin of PTV to cover 95% intrafractional motion was adequate in Group A but not in Group B., Competing Interests: The authors declare that they have no conflicts of interests., (© 2020 Kang et al.)

Background: We aimed to investigate the natural course of coronary artery calcium progression in an Asian population with a baseline coronary artery calcium (CAC) score of zero, and to determine subclinical coronary atherosclerosis., Methods: Four hundred fifty-nine subjects with at least two CAC scans with an initial score of zero were included. CAC progression (+) was defined by the development of any CAC (i.e., CAC > 0) during subsequent CT scans. Clinical characteristics and Framingham risk profiles were also recorded., Results: Among 459 subjects, 106 (23.09%) experienced CAC progression during the average follow-up period of 5.71 ± 2.68 years. Older age, male gender, HDL-C, total cholesterol and higher Framingham risk score were independently associated with CAC progression. Framingham risk score had the better discriminative ability (AUC = 0.660) to predict CAC progression compared to the other parameters with a sensitivity of 75.24% and specificity of 53.95%. For the double zero score with coronary artery atherosclerosis prediction, older age, triglycerides, hypertension, and Framingham risk score were significantly associated with these events. Among these parameters, Framingham risk score may be a relatively acceptable parameter with high negative predictive (NPV = 96.4%) value to rule out double zero score with obstructive coronary artery atherosclerosis scenario with an optimum cut-off value of <16.9 (AUC =0.652, sensitivity of 57.69%; specificity of 68.82%)., Conclusions: A baseline zero CAC score in asymptomatic Chinese population with low to intermediate risk have a low incidence for CAC progression within the 5-years period. For CAC progression prediction, Framingham risk score with the cutoff < 11.1 may help confirm subjects at low risk to improve cardiovascular risk stratification and reclassification in the field of preventive cardiology.

Graphene near charge neutrality is expected to behave like a quantum-critical, relativistic plasma-the "Dirac fluid"-in which massless electrons and holes collide at a rapid rate. We used on-chip terahertz spectroscopy to measure the frequency-dependent optical conductivity of clean, micrometer-scale graphene at electron temperatures between 77 and 300 kelvin. At charge neutrality, we observed the quantum-critical scattering rate characteristic of the Dirac fluid. At higher doping, we detected two distinct current-carrying modes with zero and nonzero total momenta, a manifestation of relativistic hydrodynamics. Our work reveals the quantum criticality and unusual dynamic excitations near charge neutrality in graphene., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Background: Arteriovenous grafting offers an alternative for patients whose vessels are unsuitable for arteriovenous fistula. However, as a result of subcutaneous tunnel dissection, postoperative pain and edema of the operated limb present early after surgery. As a traditional therapeutic approach, cryotherapy has the ability to suppress postoperative pain and edema., Aims: The purpose of the study was to investigate the feasibility of cryotherapy after arteriovenous graft surgery to decrease perioperative medication usage., Design: This study was a randomized controlled trial., Setting: A large integrated health care facility in South China., Participants/subjects: A total of 85 hemodialysis patients who received arteriovenous graft surgery from March 2011 to February 2017 were enrolled., Methods: The participants were divided into an intervention group and a control group according to the postoperative management. Ice packs were applied covering the operative forearm for 120 minutes after wound closure in the intervention group. General information, pain score, analgesic consumption, wound inflammation, forearm edema, and participant satisfaction were compared between the two groups., Results: Cryotherapy-treated patients required less analgesia (26.19% vs. 48.84%, p < .05), reported lower pain score from 30 minutes to 48 hours postoperative (p < .05), less wound inflammation (11.90% vs. 25.58%, p < .05), and higher participant satisfaction (8.92 ± 0.57 vs. 6.52 ± 0.63, p < .05), whereas the incidence of forearm edema was equivalent (p > .05). No adverse events were reported in either group., Conclusions: Cryotherapy is a preferable intervention for patients after arteriovenous graft implantation as a result of its favorable cost, convenience, and fewer side effects., (Copyright © 2019 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.)

Development of the wideband and tunable quasi-optic terahertz (THz) components is in high demand. In this work, we demonstrate a tunable achromatic quarter-wave plate (AQWP) for the THz frequency range. The phase retardation of this device can be set at 90° ± 9° from 0.20 to 0.50 THz. The operation range from 0.20 to 0.50 THz can be tuned to from 0.30 to 0.70 THz by introducing three nematic liquid crystals phase retarders, of which the birefringence can be magnetically tuned. The frequency-dependent phase retardation is in good agreement with theoretical predictions.

Background and Aim: Colonoscopy can be performed with two-operator (2OP) or one-operator (1OP) methods. This study aimed to investigate the feasibility and colonoscopy quality outcomes for the two different colonoscopy insertion techniques., Methods: One colonoscopist from Changhua Christian Hospital learned and changed the colonoscopy insertion technique from 2OP to 1OP during 2013. Real-life results of screening colonoscopies performed by this colonoscopist between these two insertion techniques (year 2012: 2OP vs year 2014: 1OP) were retrospectively reviewed and compared., Results: In total, 219 screening colonoscopies were reviewed (2OP group, n = 103 vs 1OP group, n = 116). No differences were noted between both groups in terms of patient age, gender, weight, and height. The overall cecum intubation was 98.2%, adenoma detection rate (ADR) was 29.7%, and colonoscopy withdrawal time was 518.58 ± 972.04 s. On comparing colonoscopy quality outcomes between both methods, no differences were observed in cecal intubation rates (2OP vs 1OP: 100 vs 96.6%, P = 0.1626), ADR (28 vs 31%, P = 0.7401), and colonoscopy withdrawal time (454.88 ± 178.21 vs 576.92 ± 1325.01 s, P = 0.355). However, the 1OP group demonstrated significantly shorter colonoscopy insertion time (2OP vs 1OP: 298.28 ± 202.95 vs 216.21 ± 121.99 s, P = 0.003)., Conclusion: Colonoscopy quality outcomes were not impaired when one endoscopist changed the colonoscopy practice pattern from 2OP to 1OP. However, 1OP significantly shortened the colonoscopy insertion time.

Context: Tension-free hernioplasty under local anesthetic infiltration is a reasonable choice for end-stage renal disease patients with hernia., Objectives: The purpose of the study was to investigate the feasibility of cryotherapy after hernioplasty surgery to relieve pain and scrotal edema., Methods: This was a prospective, randomized, and controlled trial held in a large integrated health care facility in South China. One hundred sixty-nine male patients on hemodialysis and scheduled for hernioplasty were enrolled between March 2013 and February 2017. The participants were divided into an intervention group and a control group. In the intervention group, ice packs were applied after surgery. Demographic information, vital signs, pain score, opioid consumption, wound inflammation, scrotal edema, and patient satisfaction were compared between the two groups. The primary outcome was pain score., Results: Cryotherapy-treated patients required less opioid consumption (5.95 vs. 15.29 mg; P < 0.05), reported lower pain scores from 30 minutes to 48 hours after operation (P < 0.05), less wound inflammation (11.90 vs. 32.94%; P < 0.05), lower incidence of scrotal edema in the first and second days (P < 0.05), and higher patient satisfaction (8.95 vs. 6.50 cm; P < 0.05), with stable vital signs throughout the monitoring period (P > 0.05)., Conclusion: Owing to its favorable cost, convenience, and low frequency of adverse effects, cryotherapy is useful for end-stage renal disease populations after hernioplasty to relieve pain and scrotal edema., (Copyright © 2018 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.)

Beauveria bassiana is a potential candidate for use as an environmentally friendly bio-pesticide. We studied the infection process and histopathology of B. bassiana strain NDBJJ-BFG infection of the Colorado potato beetle (Leptinotarsa decemlineata) using scanning electron microscopy and hematoxylin-eosin staining of tissue sections. The results show that the fungus penetrated the insect epidermis through germ tubes and appressoria after spraying the larvae with conidial suspensions. The conidia began to germinate after 24 h and invade the epidermis. After 48 h, the conidia invaded the larvae with germ tubes and began to enter the haemocoel. By 72 h, hyphae had covered the host surface and had colonized the body cavity. The dermal layer was dissolved, muscle tissues were ruptured and adipose tissue was removed. The mycelium had damaged the intestinal wall muscles, and invaded into intestinal wall and midfield cells resulting in cell separation and tracheal deformation. After 96 h of inoculation, the internal structure of the larvae was destroyed. The research shows that B. bassiana NDBJJ-BFG surface inoculation resulted in a series of histopathological changes to the potato beetle larvae that proved lethal within 72 h. This indicated that this fungus has a high pathogenicity to Colorado potato beetle larvae., (Copyright © 2017. Published by Elsevier Ltd.)

Prolonged cardiac arrest with pulseless electrical activity (PEA) results in death if its aetiology cannot be corrected immediately. We describe the case of a 75-year-old man with chest pain and his electrocardiogram (ECG) revealing ST-segment elevation in leads II, III, and aVf. Inferior wall myocardial infarction was subsequently diagnosed. Before performing emergency coronary angiography, however, a sudden cardiac arrest with PEA developed and the patient was placed on advanced cardiac life support. Oxygenation support for the extracorporeal membrane was initiated approximately 65min after prolonged cardiopulmonary resuscitation. Emergency coronary arteriogram showed no obstructive lesions in the right coronary artery. This result, however, was not consistent with the ECG findings, and thus, a massive pulmonary embolism was suspected. Subsequent pulmonary artery angiography showed severe emboli in bilateral branches of the pulmonary arteries. Catheter-directed thrombolysis with urokinase was administered, which ultimately failed, and surgical embolectomy was performed with extracorporeal membrane oxygenation support. After the above intervention, the patient was discharged on hospital day 60 without any sequelae or neurological deficits., (Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.)

Purpose: To evaluate the elasticity of the coracohumeral ligament (CHL) in healthy individuals and patients with clinical findings suggestive of unilaterally involved adhesive capsulitis of the shoulder (ACS)., Materials and Methods: The institutional review board approved this single-institution prospective study, which was performed between November 15, 2012, and July 8, 2014. Informed consent was obtained from all subjects. Measurement of CHL thickness was performed in the axial oblique plane under shoulder maximal external rotation. Shear-wave elastography (SWE) was used to evaluate elasticity of the CHL in healthy individuals (11 men, 19 women aged 22-62 years) and those with clinical findings suggestive of ACS (nine men, 11 women aged 41-70 years). SWE was performed in the shoulder-neutral position and under maximal external rotation. The Wilcoxon signed-rank test was performed to compare the thickness and elastic modulus of the CHL between bilateral shoulders., Results: In all subjects, the CHL elastic modulus was larger under maximal external rotation than in the neutral position (P < .001 for all). For healthy subjects, there was no significant difference in the CHL elastic modulus between the dominant and nondominant shoulders. For patients presumed to have ACS, the CHL thickness was significantly greater in the symptomatic shoulder than in the unaffected shoulder (P < .001). The CHL elastic modulus of the symptomatic shoulder (median, 234.8 kPa; interquartile range [IQR], 174.4-256.7 kPa) was significantly greater than that of the unaffected shoulder (median, 203.3 kPa; IQR, 144.1-242.7 kPa) in the shoulder-neutral position (P = .004) but not under maximal external rotation (P = .123). When bilateral shoulders were maintained at the same angle of external rotation, the CHL elastic modulus was greater in the symptomatic shoulder than in the unaffected shoulder (P = .005)., Conclusion: In patients with clinical findings suggestive of ACS, SWE showed that the CHL is stiffer in the symptomatic shoulder than in the unaffected shoulder., (© RSNA, 2015.)

We present a measurement of the time-resolved photoelectron kinetic energy spectrum of ethylene using 156 nm and 260 nm laser pulses. The 156 nm pulse first excites ethylene to the (1)B1u (ππ(∗)) electronic state where 260 nm light photoionizes the system to probe the relaxation dynamics with sub-30 fs resolution. Recent ab initio calculations by Mori et al. [J. Phys. Chem. A 116, 2808-2818 (2012)] have predicted an ultrafast population transfer from the initially excited state to a low-lying Rydberg state during the relaxation of photoexcited ethylene. The measured photoelectron kinetic energy spectrum reveals wave packet motion on the valence state and shows indications that the low-lying π3s Rydberg state is indeed transiently populated via internal conversion following excitation to the ππ(∗) state, supporting the theoretical predictions.

Indium-tin-oxide nanowhiskers were employed as transparent electrodes in a liquid-crystal terahertz phase shifter. Transmittance of the device was as high as ∼75%. Phase shift exceeding π/2 at 1.0 THz is achieved in a ∼500  μm-thick cell. The driving voltage required for the device operating as a quarter-wave plate was as low as 17.68 V (rms), an improvement of nearly an order of magnitude over previous work.

Aflatoxins (AFs), a group of mycotoxins, are generally produced by fungi Aspergillus species. The naturally occurring AFs including AFB1, AFB2, AFG1, and AFG2 have been clarified as group 1 human carcinogen by International Agency for Research on Cancer. Developing a sensitive analytical method has become an important issue to accurately quantify trace amount of AFs in foodstuffs. In this study, we employed a microfluidic chip-based nano LC (chip-nanoLC) coupled to triple quadrupole mass spectrometer (QqQ-MS) system for the quantitative determination of AFs in peanuts and related products. Gradient elution and multiple reaction monitoring were utilized for chromatographic separation and MS measurements. Solvent extraction followed by immunoaffinity solid-phase extraction was employed to isolate analytes and reduce matrix effect from sample prior to chip-nanoLC/QqQ-MS analysis. Good recoveries were found to be in the range of 90.8%-100.4%. The linear range was 0.048-16 ng g(-1) for AFB1, AFB2, AFG1, AFG2 and AFM1. Limits of detection were estimated as 0.004-0.008 ng g(-1). Good intra-day/inter-day precision (2.3%-9.5%/2.3%-6.6%) and accuracy (96.1%-105.7%/95.5%-104.9%) were obtained. The applicability of this newly developed chip-nanoLC/QqQ-MS method was demonstrated by determining the AFs in various peanut products purchased from local markets., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Indium-tin-oxide (ITO) nanorods (NRs) and nanowhiskers (NWhs) were fabricated by an electron-beam glancing-angle deposition (GLAD) system. These nanomaterials are of interests as transparent conducting electrodes in various devices. Two terahertz (THz) time-domain spectrometers (TDS) with combined spectral coverage from 0.15 to 9.00 THz were used. These allow accurate determination of the optical and electrical properties of such ITO nanomaterials in the frequency range from 0.20 to 4.00 THz. Together with Fourier transform infrared spectroscopic (FTIR) measurements, we found that the THz and far-infrared transmittance of these nanomaterials can be as high as 70% up to 15 THz, as opposed to about 9% for sputtered ITO thin films. The complex conductivities of ITO NRs, NWhs as well films are well fitted by the Drude-Smith model. Taking into account that the volume filling factors of both type of nanomaterials are nearly same, mobilities, and DC conductivities of ITO NWhs are higher than those of NRs due to less severe carrier localization effects in the former. On the other hand, mobilities of sputtered ITO thin films are poorer than ITO nanomaterials because of larger concentration of dopant ions in films, which causes stronger carrier scattering. We note further that consideration of the extreme values of Re{σ} and Im{σ} as well the inflection points, which are functions of the carrier scattering time (τ) and the expectation value of cosine of the scattering angle (γ), provide additional criteria for accessing the accuracy of the extraction of electrical parameters of non-Drude-like materials using THz-TDS. Our studies so far indicate ITO NWhs with heights of ~1000 nm show outstanding transmittance and good electrical characteristics for applications such as transparent conducting electrodes of THz Devices.

Omohyoid muscle syndrome has a characteristic feature of a protruding lateral neck mass during swallowing. We present a case of omohyoid muscle syndrome diagnosed based on the clinical presentation and a dynamic imaging study. Botulinum toxin was injected into the inferior belly of one omohyoid muscle, and the neck mass resolved., (Copyright © 2012 Wiley Periodicals, Inc.)

Novel peripheral nerve conduits containing the negatively charged Tremella fuciformis polysaccharide (TF) were prepared, and their efficacy in bridging a critical nerve gap was evaluated. The conduits were made of poly(D,L-lactide) (PLA) with asymmetric microporous structure. TF was immobilized on the lumen surface of the nerve conduits after open air plasma activation. The TF-modified surface was characterized by the attenuated total reflection Fourier-transformed infrared spectroscopy and the scanning electron microscopy. TF modification was found to enhance the neurotrophic gene expression of C6 glioma cells in vitro. TF-modified PLA nerve conduits were tested for their ability to bridge a 15 mm gap of rat sciatic nerve. Nerve regeneration was monitored by the magnetic resonance imaging. Results showed that TF immobilization promoted the nerve connection in 6 weeks. The functional recovery in animals receiving TF-immobilized conduits was greater than in those receiving the bare conduits during an 8-month period. The degree of functional recovery reached ~90% after 8 months in the group of TF-immobilized conduits.

Indium-tin-oxide (ITO) nanowhiskers with attractive electrical and anti-reflection properties were prepared by the glancing-angle electron-beam evaporation technique. Structural and crystalline properties of such nanostructures were examined by scanning transmission electron microscopy and X-ray diffraction. Their frequency-dependent complex conductivities, refractive indices and absorption coefficients have been characterized with terahertz time-domain spectroscopy (THz-TDS), in which the nanowhiskers were considered as a graded-refractive-index (GRIN) structure instead of the usual thin film model. The electrical properties of ITO GRIN structures are analyzed and fitted well with Drude-Smith model in the 0.2~2.0 THz band. Our results indicate that the ITO nanowhiskers and its bottom layer atop the substrate exhibit longer carrier scattering times than ITO thin films. This signifies that ITO nanowhiskers have an excellent crystallinity with large grain size, consistent with X-ray data. Besides, we show a strong backscattering effect and fully carrier localization in the ITO nanowhiskers.

Terahertz (THz) radiation can be generated more efficiently from a low-temperature-grown GaAs (LT-GaAs) photoconductive (PC) antenna by considering the two-photon absorption (TPA) induced photo-carrier in the photoconductor. A rate-equation-based approach using the Drude-Lorentz model taking into account the band-diagram of LT-GaAs is used for the theoretical analysis. The use of transform-limited pulses at the PC antenna is critical experimentally. Previously unnoticed THz pulse features and anomalously increasing THz radiation power rather than saturation were observed. These are in good agreement with the theoretical predictions. The interplay of intensity dependence and dynamics of generation of photoexcited carriers by single-photon absorption and TPA for THz emission is discussed., (© 2011 Optical Society of America)

Study Design: Case report., Objective: Vertebral osteomyelitis, usually presented with back pain and local tenderness, can pose a great challenge of early diagnosis among spinal cord injury (SCI) patients who lost sensation below the injured level. We reported a paraplegic patient who had recurrent febrile episodes after being treated as urinary tract infection initially and was discovered later to have vertebral osteomyelitis., Case Report: A 41-year-old man, completely paralyzed at the T11 level and with Foley catheterization for 9 years, was re-admitted within 2 weeks for recurrent fever, turbid urine, bacteriuria and bacteremia with Escherichia coli. Spine X-ray and renal, cardiac and abdominal ultrasonography showed no definite lesions related to infection in a previous admission. Intermittently febrile episodes continued despite treatment with antibiotics for 1 week. He had no pressure sores or other wounds. Computerized tomography and magnetic resonance imaging showed lumbosacral osteomyelitis and bilateral paravertebral abscess. The patient underwent debridement of paravertebral tissue. Fever subsided soon after surgery and the patient continued antibiotics and remained free of fever at a 1-year follow-up., Conclusion: It can be challenging to diagnose vertebral osteomyelitis below injury levels in SCI patients. Vertebral osteomyelitis should be considered in febrile SCI patients even with known infectious foci, as classic symptoms of osteomyelitis are lacking in this population.

The performance of an asymmetric conduit made of microporous polylactic acid (PLA) in promoting the long-term peripheral nerve regeneration across a 20-mm-long sciatic nerve gap was evaluated by a rabbit sciatic nerve transection model. Magnetic resonance imaging (MRI) was employed to monitor the nerve regeneration process. The extents of nerve regeneration and conduit degradation were quantified by image analysis. Functional and histological analyses were followed to assess nerve reinnervation. MR images showed that the transected nerve was connected at about 4 months. The diameter of the regenerated nerve continued to increase while the conduit was gradually degraded. The conduit was completely degraded in 18 months. The degradation kinetics in vivo was estimated based on MR images. The functional recovery after 18 months was ∼82% based on electrophysiology. The extension range of the operated limb was slowly recuperated to ∼81% at 18 months. Histology showed that nerve bundles were self-assembled after 16-18 months, but the morphologies were still different from those of normal sciatic nerve. This was the first work on the long-term evaluation of peripheral nerve regeneration in a rabbit model, and the first to report the use of MRI to obtain the real-time images of regenerated nerve in a biomaterial conduit as well as to define the degradation rate of the conduit in vivo. The platform established in this study serves to evaluate the regeneration of larger-diameter (>3-mm) nerve across a long-gap bridged by a conduit., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Urinary 8-isoprostaglandin F(2α) (8-isoPGF(2α)) has been reported as an important biomarker to indicate the oxidative stress status in vivo. In order to quantitatively determine the low contents of 8-isoPGF(2α) (in sub- to low ng mL(-1) range) in physiological fluids, a sensitive detection method has become an important issue. In this study, we employed a microfluidic chip-based nano liquid chromatography (chip-nanoLC) with on-chip sample enrichment coupled to triple quadrupole mass spectrometer (QqQ-MS) for the quantitative determination of 8-isoPGF(2α) in human urine. This chip-nanoLC unit integrates a microfluidic switch, a chip column design having a pre-column (enrichment column) for sample enrichment prior to an analytical column for separation, as well as a nanospray emitter on a single polyimide chip. The introduction of enrichment column offers the advantages of online sample pre-concentration and reducing matrix influence on MS detection to improve sensitivity. In this study, the chip-nanoLC consisting of Zorbax 300A SB-C18 columns and Agilent QqQ Mass spectrometer were used for determining 8-isoPGF(2α) in human urine. Gradient elution was employed for effective LC separation and multiple reaction monitoring (MRM) was utilized for the quantitative determination of 8-isoPGF(2α) (m/z 353→193). We employed liquid-liquid extraction (LLE)/solid-phase extraction (SPE) for extracting analyte and reducing matrix effect from urine sample prior to chip-nanoLC/QqQ-MS analysis for determining urinary 8-isoPGF(2α). Good recoveries were found to be in the range of 83.0-85.3%. The linear range was 0.01-2 ng mL(-1) for urinary 8-isoPGF(2α). In addition, the proposed method showed good precision and accuracy for 8-isoPGF(2α) spiked synthetic urine samples. Intra-day and inter-day precisions were 1.8-5.0% and 4.3-5.8%, respectively. The method accuracy for intra-day and inter-day assays ranged from 99.3 to 99.9% and 99.4 to 99.7%, respectively. Due to its rapidity, enhanced sensitivity, and high recovery, this chip-nanoLC/QqQ-MS system was successfully utilized to determine the physiological biomarkers such as 8-isoPGF(2α) in human urine for clinical diagnosis., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Betel quid chewing, which contributes high concentration of safrole in saliva, is a popular oral habit in Taiwan. Safrole is a documented rodent hepatocarcinogen, yet its hepatocarcinogenic potential in human is not known. Here, we used LC/ESI-ITMS(n) and LC/QTOF-MS confirmed safrole-dGMP as reference standard to detect the safrole-DNA adduct in hepatic tissues from HBsAg-/HCV-seronegative hepatocellular carcinoma patients by (32)P-postlabeling. We first synthesized and confirmed safrole-dGMP by LC/MS. Two isomeric safrole-dGMPs were characterized as N(2)-(trans-isosafrol-3'-yl) deoxyguanosine and N(2)-(safrol-1'-yl) deoxyguanosine. This technique was able to detect hepatic safrole-DNA adduct in mice that were treated with safrole but not sensitive enough to detect safrole-DNA adduct in human samples. Using the nuclease P1 version of the (32)P-postlabeling technique, we detected the presence of safrole-DNA adduct in two out of 28 hepatic tissues from hepatocellular carcinoma patients, and only these two patients had a history of betel quid chewing lasting more than 10 years. From co-chromatography with the mass confirmed safrole-dGMPs, this safrole-DNA adduct was identified as N(2)-(trans-isosafrol-3'-yl) deoxyguanosine. These results suggest that betel quid-containing safrole might be involved in the pathogenesis of hepatocellular carcinoma in human beings and LC/MS has the potential to identify DNA adducts in clinical samples.