bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of T1 relaxation time in rotating frame (T1ρ) and apparent diffusion coefficient to estimate cerebral stroke evolution
Authors: Tan Yuefa , Xu Jun , Chen Ruiying , Chen Bin , Xu Juan , Ren Daokun , Chan Queenie , Mei Yingjie , Wu Yuankui , Xu Yikai 
Published: February 2018

BackgroundThe major factor for the appropriate treatment strategies for ischemia patients is its onset timing.Purpose/HypothesisTo study to evaluate the diagnostic accuracy of T1 relaxation time in a rotating frame (T1ρ) and apparent diffusion coefficient (ADC) from MRI to estimate ischemia stages.Study TypeProspective.Population/Subjects/Phantom/Specimen/Animal ModelIn all, 73 patients (49 males, aged 29–78 years and 24 females, aged 22–94 years) with ischemia were prospectively imaged with T1ρ and diffusion MRI during the postischemic period.Field Strength/Sequence3T/T1ρ and diffusion‐weighted imaging (DWI).AssessmentIschemic parenchyma included tissue with elevated signal areas on DWI and correlative hypointense areas on ADC maps.Statistical TestsThe sensitivity of variables to ischemia time was quantified by analyzing the respective correlations of these values with onset time.ResultsΔT1ρ (ipsilateral‐contralateral differences in T1ρ) (R2 = 0.956) and T1ρipsi (ipsilateral ischemia T1ρ values) (R2 = 0.941) were elevated in all ischemic lesions; these values increased linearly as a function of time, unlike ΔADC (ipsilateral‐contralateral differences in ADC) (R2 = –0.410) and ADCipsi (ipsilateral ischemia ADC values) (R2 = 0.550). ΔT1ρ and T1ρipsi were significantly different between all stages (P < 0.01), except the acute and hyperacute stages (P = 0.589 for ΔT1ρ, P = 0.290 for T1ρipsi, respectively), but ΔADC and ADCipsi only between the late subacute and early subacute stages (P < 0.01) and the late subacute and chronic stages (P < 0.01).Data ConclusionThese data suggest that T1ρ can provide estimates for the ischemic time in patients. T1ρ has the potential to outperform diffusion for single‐timepoint examination because the T1ρ change during strokes is positive and linear. If patients with suspected stroke are scanned by MRI within the appropriate timeframe, T1ρ may provide tools for evaluating stroke onset, potentially aiding in treatment strategies.Level of Evidence: 4Technical Efficacy: Stage 3J. Magn. Reson. Imaging 2018;47:1247–1254.
Liquid chromatography/mass spectrometry‐based plasma metabolic profiling study of escitalopram in subjects with major depressive disorder
Authors: Bandu Raju , Lee Hyun Jeong , Lee Hyeong Min , Ha Tae Hyon , Lee Heon‐Jeong , Kim Se Joo , Ha Kyooseob , Kim Kwang Pyo 
Published: February 2018

AbstractLiquid chromatography‐mass spectrometry (LC‐MS) method revealed the plasma metabolite profiles in major depressive disorder patients treated with escitalopram (ECTP) (n = 7). Depression severity was assessed according to the 17‐item Hamilton Depression Rating Scale. Metabolic profiles were derived from major depressive disorder subject blood samples collected after ECTP treatment. Blood plasma was separated and processed in order to effectively extract metabolites, which were then analyzed using LC‐MS. We identified 19 metabolites and elucidated their structures using LC‐tandem MS (LC‐MS/MS) combined with elemental compositions derived from accurate mass measurements. We further used online H/D exchange experiments to verify the structural elucidations of each metabolite. Identifying molecular metabolites may provide critical insights into the pharmacological and clinical effects of ECTP treatment and may also provide useful information informing the development of new antidepressant treatments. These detailed plasma metabolite analyses may also be used to identify optimal dose concentrations in psychopharmacotherapeutic treatment through drug monitoring, as well as forming the basis for response predictions in depressed subjects.
Evaluation and validation of an ion mobility quadrupole time‐of‐flight mass spectrometry pesticide screening approach
Authors: Bauer Anna , Kuballa Juergen , Rohn Sascha , Jantzen Eckard , Luetjohann Jens 
Published: February 2018

AbstractAn ion mobility quadrupole time‐of‐flight mass spectrometry‐based pesticide suspect screening methodology was developed and validated covering 20 plant‐derived food matrices deriving from six commodity groups of different complexity according to the actual European Commission document SANTE/11813/2017 applying a QuEChERS sample preparation protocol. The method combines ultra‐performance liquid chromatography, traveling wave ion mobility, and quadrupole time‐of‐flight mass spectrometry. Besides the determination of the physicochemical property collision cross‐section and the establishment of a corresponding scientific suspect screening database comprising 280 pesticides for several pesticides, different protomers, sodium adducts, as well as dimers were identified in ion mobility spectrometry traces. Additionally, collision cross‐section values were included in the validation requirements regarding chromatography and mass spectrometry for the detection of pesticides. A collision cross‐section value window was analyzed within a tolerable error of ±2%. For this cross‐matrix validation, screening detection limits were determined at concentration levels of 0.100 mg/kg (84% of the original pesticide scope), 0.010 mg/kg (56%), and 0.001 mg/kg (21%). By application of ion mobility spectrometry, the compound identification was improved due to independence of commodity of concern and concentration levels of analyte molecules, as false assignments are reduced by application of a collision cross‐section range.
Telemedicine in otolaryngology outpatient setting—single Center Head and Neck Surgery experience
Authors: Rimmer Ryan A. , Christopher Vanessa , Falck Ailsa , de Azevedo Pribitkin Edmund , Curry Joseph M. , Luginbuhl Adam J. , Cognetti David M. 
Published: February 2018

Objectives/HypothesisWe present our experience with telemedicine visits in an otolaryngology outpatient setting within our institution's Center for Head and Neck Surgery.Study DesignRetrospective chart review.MethodsA review of telemedicine outpatient encounters examining patient demographics, visit type, and wait times was conducted. Internet‐based navigation applications were used to calculate travel distance and estimate commute time to our clinic. Patient survey responses were reviewed.ResultsTwo hundred fifty telemedicine encounters were reviewed between December 2015 and June 2017. The average age of patients was 50 years (range, 4–87 years). Patients waited an average of 10 minutes for their telemedicine appointments and avoided an average estimated commute time of 78 minutes (64 miles). The majority of visits were postoperative encounters (70%). Clinical follow‐up of recent results or nonpostoperative complaints accounted for the remaining 30% of visits. All patients were offered a post‐telemedicine survey, and 78 (31%) completed the survey. Of the respondents, 95% of patients reported that they were satisfied with their visit. Among patients who were dissatisfied, wait time and technical issues were cited as reasons.ConclusionsWith appropriate patient selection, telemedicine is an effective way to safely conduct outpatient clinic visits while maintaining high patient satisfaction. It can be particularly useful for institutions with large catchment areas to minimize travel times and increase ease of communication.Level of Evidence4. Laryngoscope, 128:2072–2075, 2018
Clinical criteria for CT scan evaluation of upper digestive tract fishbone
Authors: Jahshan Forsan , Sela Eyal , Layous Eli , Levy Einat , Assadi Niddal , Shilo Etgar , Ibrahim Nour , Maayan Dor , Ronen Ohad 
Published: February 2018

ObjectivesTo establish clinical criteria for performing computed tomography scan for suspected upper digestive tract fishbone.MethodsThis is a prospective study of all adult patients referred to the otolaryngology emergency department at our medical center for suspected fishbone in the upper digestive tract after no fishbone was seen on physical examination. The patients were divided into two groups: 1) The first was a high clinical suspicion group, which included patients with at least one of the following criteria: drooling, accumulation of saliva in the sinus piriformis, fever, referral 24 hours after the ingestion with worsening/continuing symptoms, and readmission. These patients underwent nonenhanced CT scan (NECT) of the neck. 2) The second was a low clinical suspicion group, which included patients discharged with no NECT performed. These patients were followed at 1 week and 3 months.ResultsOne hundred and fourteen patients were included in the study; the median age was 41 years. Half of the patients arrived at the emergency department within 7 hours. There were no false negatives. The negative predictive value and sensitivity were 100%. Positive predictive value and specificity were 28.5% and 65%, respectively. Referral to the emergency department 24 hours after the ingestion with continuing symptoms had the highest false positive rate.ConclusionsOur clinical criteria score for excluding foreign body fishbone in the upper aerodigestive tract was established. According to this score, a NECT can be spared in about 75% of all cases, thus reducing unnecessary ionizing radiation, stay at the emergency department, and costs with a very high NPV of almost 99%.Level of Evidence4. Laryngoscope, 2467–2472, 2018
Heparin mimetics with anticoagulant activity
Authors: Nahain Abdullah Al , Ignjatovic Vera , Monagle Paul , Tsanaktsidis John , Ferro Vito 
Published: February 2018

AbstractHeparin, a sulfated polysaccharide belonging to the glycosaminoglycan family, has been widely used as an anticoagulant drug for decades and remains the most commonly used parenteral anticoagulant in adults and children. However, heparin has important clinical limitations and is derived from animal sources which pose significant safety and supply problems. The ever growing shortage of the raw material for heparin manufacturing may become a very significant issue in the future. These global limitations have prompted much research, especially following the recent well‐publicized contamination scandal, into the development of alternative anticoagulants derived from non‐animal and/or totally synthetic sources that mimic the structural features and properties of heparin. Such compounds, termed heparin mimetics, are also needed as anticoagulant materials for use in biomedical applications (e.g., stents, grafts, implants etc.). This review encompasses the development of heparin mimetics of various structural classes, including synthetic polymers and non‐carbohydrate small molecules as well as sulfated oligo‐ and polysaccharides, and fondaparinux derivatives and conjugates, with a focus on developments in the past 10 years.
Longterm persistence and nonrecurrence of depression treatment in Germany: a four‐year retrospective follow‐up using linked claims data
Authors: Wagner Christoph J. , Dintsios Charalabos Markos , Metzger Florian G. , L'Hoest Helmut , Marschall Ursula , Stollenwerk Bjoern , Stock Stephanie 
Published: February 2018

AbstractObjectivesTo measure persistence and nonrecurrence of depression treatment and investigate potential risk factors.MethodsWe retrospectively observed a closed cohort of insurees with new‐onset depression treatment in 2007 and without most psychiatric comorbidity for 16 quarters (plus one to ascertain discontinuation). We linked inpatient/outpatient/drug‐data per person and quarter. Person‐quarters containing specified depression services were classified as depression‐treatment‐person‐quarters (DTPQ). We defined longterm‐DTPQ‐persistence as 16 + 1 continuous DTPQ and longterm‐DTPQ‐nonrecurrence as 12 continuous quarters without DTPQ and used multivariate logistic regression to explore associations with these outcomes.ResultsWithin first 16 quarters, 28,348 patients' first period (total time) persisted for a mean/median 5.4/3 (8.7/8) quarters. Fourteen percent had longterm‐DTPQ‐persistence, associated (p < .05) with baseline hospital (odds ratio, OR = 1.80), psychotherapy/specialist‐interview and antidepressants (OR = 1.81), age (years, OR = 1.03), unemployment (OR = 1.21), retirement (OR = 1.31), and insured as a dependent (OR = 1.32). Thirty‐four percent had longterm‐DTPQ‐nonrecurrence, associated with psychotherapy/specialist‐interview (OR = 1.40), antidepressants (OR = 0.54), female sex (OR = 0.84), age (years, OR = 0.99), retirement (OR = 1.18), and insured as a dependent (OR = 0.88). Women differed for episodic and not chronic treatment.ConclusionTreatment measures compared to survey's symptoms measures. We suggest further research on “treatment‐free‐time.” Antidepressants(−) and psychotherapy/specialist‐interview(+) were significantly associated with longterm‐DTPQ‐nonrecurrence. This was presumably moderated by possible short‐time/low‐dosage antidepressants use(−) and selective therapy assignment(+). Sample selectivity limited data misclassification.
Whole‐body MRI for metastatic cancer detection using T2‐weighted imaging with fat and fluid suppression
Authors: Wang Xinzeng , Pirasteh Ali , Brugarolas James , Rofsky Neil M. , Lenkinski Robert E. , Pedrosa Ivan , Madhuranthakam Ananth J. 
Published: February 2018

PurposeTo develop a whole‐body MRI technique at 3T with improved lesion conspicuity for metastatic cancer detection using fast, high‐resolution and high SNR T2‐weighted (T2W) imaging with simultaneous fat and fluid suppression.Theory and MethodsThe proposed dual‐echo T2‐weighted acquisition for enhanced conspicuity of tumors (DETECT) acquires 4 images, in‐phase (IP) and out‐of‐phase (OP) at a short and a long TE using single‐shot turbo spin echo. The IP/OP images at the short and long TEs are reconstructed using the standard Dixon and shared‐field‐map Dixon reconstruction respectively, for robust fat–water separation. An adaptive complex subtraction between the 2 TE water‐only images achieves fluid attenuation. DETECT imaging was optimized and evaluated in whole‐body imaging of 5 healthy volunteers, and compared against diffusion‐weighted imaging with background suppression (DWIBS) in 5 patients with known metastatic renal cell carcinoma.ResultsRobust fat–water separation and fluid attenuation were achieved using the shared‐field‐map Dixon reconstruction and adaptive complex subtraction, respectively. DETECT imaging technique generated co‐registered T2W images with and without fat suppression, heavily T2W, and fat and fluid suppressed T2W whole‐body images in <7 min. Compared to DWIBS acquired in 17 min, the DETECT imaging achieved better detection and localization of lesions in patients with metastatic cancer.ConclusionDETECT imaging technique generates T2W images with high resolution, high SNR, minimal geometric distortions, and provides good lesion conspicuity with robust fat and fluid suppression in <7 min for whole‐body imaging, demonstrating efficient and reliable metastatic cancer detection at 3T.
Water suppression in the human brain with hypergeometric RF pulses for single‐voxel and multi‐voxel MR spectroscopy
Authors: Chan Kimberly L. , Ouwerkerk Ronald , Barker Peter B. 
Published: February 2018

PurposeTo develop and investigate a novel water suppression sequence with hypergeometric pulses at 3 T.MethodsSimulations were used to optimize the delays and amplitudes of 5 hypergeometric prepulses, to minimize the residual water over a range of T1 and B1 values. Single‐voxel data with hypergeometric water suppression (HGWS) prepulses were acquired in the centrum semiovale, 2 parietal regions, and insula of 7 subjects, and compared with VAPOR water suppression. Magnetic resonance spectroscopic imaging (MRSI) data using both VAPOR and HGWS prepulses were also collected and compared. Water suppression performance was calculated as the residual water peak height relative to the unsuppressed water peak. MRSI voxel‐by‐voxel comparison was performed by calculating the ratio between HGWS and VAPOR residual water peaks.ResultsIn simulations, HGWS and VAPOR are insensitive to B1 and water T1 variations, but with no B1 variation, HGWS has a lower average residual water fraction (0.0033) than that of VAPOR (0.0091). In single‐voxel acquisitions, HGWS performs better than VAPOR in all regions with a 2.3‐fold to 5.7‐fold lower residual water. In MRSI acquisitions, HGWS performs on average 2.3‐fold better than VAPOR in 98.9% of the voxels.ConclusionHGWS provides better water suppression than VAPOR in both single‐voxel and multivoxel acquisitions with a shorter sequence duration.
Feasibility of high spatiotemporal resolution for an abbreviated 3D radial breast MRI protocol
Authors: Jimenez Jorge E. , Strigel Roberta M. , Johnson Kevin M. , Henze Bancroft Leah C. , Reeder Scott B. , Block Walter F. 
Published: February 2018

PurposeTo develop a volumetric imaging technique with 0.8‐mm isotropic resolution and 10‐s/volume rate to detect and analyze breast lesions in a bilateral, dynamic, contrast‐enhanced MRI exam.MethodsA local low‐rank temporal reconstruction approach that also uses parallel imaging and spatial compressed sensing was designed to create rapid volumetric frame rates during a contrast‐enhanced breast exam (vastly undersampled isotropic projection [VIPR] spatial compressed sensing with temporal local low‐rank [STELLR]). The dynamic‐enhanced data are subtracted in k‐space from static mask data to increase sparsity for the local low‐rank approach to maximize temporal resolution. A T1‐weighted 3D radial trajectory (VIPR iterative decomposition with echo asymmetry and least squares estimation [IDEAL]) was modified to meet the data acquisition requirements of the STELLR approach. Additionally, the unsubtracted enhanced data are reconstructed using compressed sensing and IDEAL to provide high‐resolution fat/water separation. The feasibility of the approach and the dual reconstruction methodology is demonstrated using a 16‐channel breast coil and a 3T MR scanner in 6 patients.ResultsThe STELLR temporal performance of subtracted data matched the expected temporal perfusion enhancement pattern in small and large vascular structures. Differential enhancement within heterogeneous lesions is demonstrated with corroboration from a basic reconstruction using a strict 10‐second temporal footprint. Rapid acquisition, reliable fat suppression, and high spatiotemporal resolution are presented, despite significant data undersampling.ConclusionThe STELLR reconstruction approach of 3D radial sampling with mask subtraction provides a high‐performance imaging technique for characterizing enhancing structures within the breast. It is capable of maintaining temporal fidelity, while visualizing breast lesions with high detail over a large FOV to include both breasts.
Distinction of the GABA 2.29 ppm resonance using triple refocusing at 3 T in vivo
Authors: Tiwari Vivek , An Zhongxu , Wang Yiming , Choi Changho 
Published: February 2018

PurposeTo develop 1H MR spectroscopy that provides distinction of γ‐aminobutyric acid (GABA) signal at 3 T in vivo.MethodsTriple‐refocusing was tailored at 3 T, with numerical simulations and phantom validation, for distinction of the GABA 2.29‐ppm resonance from the neighboring glutamate resonance. The optimization was performed on the inter‐RF pulse time delays and the duration and carrier frequency of a non‐slice‐selective RF pulse. The optimized triple refocusing was tested in multiple regions in 6 healthy subjects, including hippocampus. The in vivo spectra were analyzed with the LCModel using in‐house basis spectra. After normalization of the metabolite signal estimates to water, the metabolite concentrations were quantified with reference to medial‐occipital creatine at 8 mM.ResultsA triple‐refocusing scheme with optimized inter‐RF pulse time delays (TE = 74 ms) was obtained for GABA detection. With optimized duration (14 ms) and carrier frequency (4.5 ppm) of the non‐slice‐selective RF pulse, the triple refocusing gave rise to distinction between the GABA 2.29‐ppm and glutamate 2.35‐ppm signals. The GABA 2.29‐ppm signal was clearly discernible in spectra in vivo (voxel size 4 to 12 mL; scan times 4.3 to 17 minutes). With a total of 24 spectra from 6 gray or white matter–dominant regions, the GABA concentration was measured to be 0.62 to 1.15 mM (Cramer‐Rao lower bound of 8 to 14%), and the glutamate level 5.8 to 11.2 mM (Cramer‐Rao lower bound of 3 to 6%).ConclusionThe optimized triple refocusing provided distinction between GABA and glutamate signals and permitted direct codetection of these metabolites in the human brain at 3 T in vivo.
Evolution of the mechanical properties and estimation of the useful lifespan of poly(lactic acid) based compounds
Authors: Anakabe Jon , Santamaria‐Echart Arantzazu , Eceiza Arantxa , Arbelaiz Aitor , Zaldua Huici Ane Miren 
Published: February 2018

AbstractThe useful lifespans of a poly(lactic acid)/poly(methyl methacrylate) (PLA/PMMA) 80/20 (wt%) blend and a poly(lactic acid)/dioctyl adipate/talc (PLA/DOA/talc) compound have been estimated by applying an Arrhenius relationship to the evolution of the mechanical properties whilst ageing. The studied PLA based systems showed lower activation energies (ca 8 − 20 kJ mol−1) than those reported in the literature for other synthetic thermoplastics, indicating lower thermo‐oxidative stability. However, both systems were interesting choices for semi‐durable applications in terms of useful lifespan estimations. The PLA/PMMA blend showed a drastic loss in stiffness at Tg due to its almost amorphous structure whereas, in contrast, PLA/DOA/talc showed acceptable mechanical properties above its glass transition temperature due to its semicrystalline structure. © 2018 Society of Chemical Industry
Supramolecular elastomers: Switchable mechanical properties and tuning photohealing with changes in supramolecular interactions
Authors: Razgoniaev Anton O. , Mikhailov Kirill I. , Obrezkov Filipp A. , Butaeva Evgeniia V. , Ostrowski Alexis D. 
Published: February 2018

ABSTRACTTo study light‐triggered self‐healing in supramolecular materials, we synthesized supramolecular thermoplastic elastomers with mechanical properties that were reversibly modulated with temperature. By changing the supramolecular architecture, we created polymers with different temperature responses. Detailed characterization of the hydrogen‐bonding material revealed dramatically different temperature and mechanical stress response due to two different stable states with changes in the hydrogen bonding interactions. A semi‐crystalline state showed no response to oscillatory shear deformations while the melt state behaved as a typical energy dissipative material with a clear crossover between storage and loss moduli. Comparison studies on heat generation after light excitation revealed no differences in photo‐thermal conversion when an Fe(II)‐phenanthroline chromophore was either physically blended into the H‐bonding polymer or covalently attached to the supramolecular network. These materials showed healing of scratches with light‐irradiation, as long as the overlap of material absorbance and laser excitation was sufficient. Differences in the efficiency and rate of photohealing were observed, depending on the type of supramolecular interaction, and these were attributed to the differences in the thermal response of the materials' moduli. Such results provide insight into how materials can be designed with chromophores and supramolecular bonding interactions to tune the light‐healing efficiency of the materials. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1003–1011