bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oxygenation‐sensitive cardiovascular magnetic resonance in hypertensive heart disease with left ventricular myocardial hypertrophy and non‐left ventricular myocardial hypertrophy: Insight from altered mechanics and cardiac BOLD imaging
Authors: Chen Bing‐Hua , Wu Rui , An Dong‐Aolei , Shi Ruo‐Yang , Yao Qiu‐Ying , Lu Qing , Hu Jiani , Jiang Meng , Deen James , Chandra Ankush , Xu Jian‐Rong , Wu Lian‐Ming 
Published: May 2018

BackgroundBOLD (blood oxygen level dependent) MRI can detect regional condition of myocardial oxygen supply and demand by means of paramagnetic properties.PurposeNoninvasive assessment of myocardial oxygenation by BOLD MRI in hypertensive patients with hypertension (HTN) left ventricular myocardial hypertrophy (LVMH) and HTN non‐LVMH and its correlation with myocardial mechanics were performed.Study TypeProspective.POPULATIONTwenty patients with HTN LVMH, 21 patients with HTN non‐LVMH, and 23 normotensive controls were enrolled.Field Strength/SequenceCine imaging, T2* and T1 mapping sequences were achieved at 3.0T.AssessmentDedicated T1 mapping, T2*, and cine imaging analysis were performed by two radiologists using cvi42.Statistical TestsOne‐way analysis of variance, Kruskal‐Wallis test, Bland‐Altman analysis, Pearson's correlation coefficient, Spearman's rank correlation.ResultsT2* values of HTN LVMH group were significantly lower versus the controls (23.78 ± 3.09 versus 30.77 ± 2.71; P < 0.001) and HTN non‐LVMH group (23.78 ± 3.09 versus 28.64 ± 4.23; P < 0.001). Left ventricular peak circumferential strain were reduced in HTN LVMH patients compared with other two groups (−11.32 [−15.64, −10.3], −16.78 [−19.35, −15.34], and −19.73 [−20.57, −18.73]; P < 0.05); and longitudinal strain of HTN LVMH patients were lower than other two groups (−11.31 ± 2.91, −15.1 ± 3.06, and −18.85 ± 1.85; P < 0.05); radial strain of HTN LVMH patients were also lower than other two groups (25.03 ± 16, 40.95 ± 17.5 and 47.9 ± 10.23; P < 0.05). Extracellular volume correlated with peak circumferential, longitudinal, and radial strain (spearman rho = 0.6, 0.64, and −0.69; P < 0.05), respectively; T2* negatively correlated with peak circumferential and longitudinal strain (spearman rho = −0.43 and −0.49; P < 0.05), respectively. Patients with lower T2* values had significant decreases in myocardial mechanics (P < 0.05).Data ConclusionHTN LVMH patients have both impaired myocardial mechanics and decreased T2* values compared with HTN non‐LVMH and normotensive groups. BOLD MRI could provide a feasible assessment modality for detecting altered T2* due to the change of de‐oxygenated hemoglobin and hence to the change of signal intensity in oxygenation‐sensitive images.Level of Evidence: 1Technical Efficacy: Stage 3J. Magn. Reson. Imaging 2018;47:1297–1306.
Pseudoprogression of brain tumors
Authors: Thust Stefanie C. , van den Bent Martin J. , Smits Marion 
Published: May 2018

This review describes the definition, incidence, clinical implications, and magnetic resonance imaging (MRI) findings of pseudoprogression of brain tumors, in particular, but not limited to, high‐grade glioma. Pseudoprogression is an important clinical problem after brain tumor treatment, interfering not only with day‐to‐day patient care but also the execution and interpretation of clinical trials. Radiologically, pseudoprogression is defined as a new or enlarging area(s) of contrast agent enhancement, in the absence of true tumor growth, which subsides or stabilizes without a change in therapy. The clinical definitions of pseudoprogression have been quite variable, which may explain some of the differences in reported incidences, which range from 9–30%. Conventional structural MRI is insufficient for distinguishing pseudoprogression from true progressive disease, and advanced imaging is needed to obtain higher levels of diagnostic certainty. Perfusion MRI is the most widely used imaging technique to diagnose pseudoprogression and has high reported diagnostic accuracy. Diagnostic performance of MR spectroscopy (MRS) appears to be somewhat higher, but MRS is less suitable for the routine and universal application in brain tumor follow‐up. The combination of MRS and diffusion‐weighted imaging and/or perfusion MRI seems to be particularly powerful, with diagnostic accuracy reaching up to or even greater than 90%. While diagnostic performance can be high with appropriate implementation and interpretation, even a combination of techniques, however, does not provide 100% accuracy. It should also be noted that most studies to date are small, heterogeneous, and retrospective in nature. Future improvements in diagnostic accuracy can be expected with harmonization of acquisition and postprocessing, quantitative MRI and computer‐aided diagnostic technology, and meticulous evaluation with clinical and pathological data.Level of Evidence: 3Technical Efficacy: Stage 2J. Magn. Reson. Imaging 2018;48:571–589.
Esophageal carcinoma: Intravoxel incoherent motion diffusion‐weighted MRI parameters and histopathological correlations
Authors: Zhu Shaocheng , Wei Yi , Gao Feifei , Li Linlin , Liu Yuehua , Huang Zixing , Tang Hehan , Zheng Dandan , Wei Xiaocheng , Sun Tingyi , Song Bin 
Published: May 2018

BackgroundThe pathological grade of esophageal carcinoma is highly determinant of patient prognosis, but it still cannot be adequately evaluated preoperatively. Compared with conventional diffusion‐weighted imaging (DWI), intravoxel incoherent motion (IVIM) diffusion‐weighted MRI can separate true molecular diffusion and perfusion in tissues and has been shown to be useful in characterizing malignant tumors. There is no report that compared IVIM and conventional DWI in grading esophageal carcinoma.PurposeTo prospectively determine the diagnostic performance of conventional DWI and IVIM models in differentiating the pathological differentiated grade of esophageal carcinoma.Study TypeProspective.PopulationA cohort comprising 81 patients with newly diagnosed esophageal squamous cell carcinoma (ESCC) between December 2015 and August 2017 were evaluated.Field Strength/Sequence3.0T, axial echo‐planer imaging, fast spin echo (FSE) sequence, IVIM sequence (b = 0, 20, 50, 80, 100, 150, 200, 400, 600, 800, 1000, 1200).AssessmentApparent diffusion coefficient (ADC), true ADC (ADCslow), pseudo ADC (ADCfast), and perfusion fraction (f) of each tumor were calculated by two independent radiologists. Histopathologic grade was used as the reference standard.Statistical TestsGames‐Howell test; diagnostic accuracy; Spearman correlation; intraclass correlation coefficient; and Bland–Altman analysis. Receiver operating characteristics (ROC) curves.ResultsADCslow demonstrated the highest area under curve (AUC) with a value of 0.830 (95% confidence interval [CI]: 0.730–0.904) and 0.816 (95% CI: 0.714–0.893) by two radiologists, followed by ADC with a value of 0.754 (95% CI: 0.646–0.843) and 0.761 (95% CI: 0.653–0.848). Good correlation was obtained between the histologic grade and ADCslow (r(R1) = 0.748, r(R2) = 0.720) and ADC (r(R1) = 0.576, r(R2) = 0.571).Data ConclusionADCslow and ADC had a significantly higher performance than the ADCfast and f, and ADCslow had a significantly higher performance than the ADC.Level of Evidence: 1Technical Efficacy: Stage 2J. Magn. Reson. Imaging 2019;49:253–261.
Radiomic features from pretreatment biparametric MRI predict prostate cancer biochemical recurrence: Preliminary findings
Authors: Shiradkar Rakesh , Ghose Soumya , Jambor Ivan , Taimen Pekka , Ettala Otto , Purysko Andrei S. , Madabhushi Anant 
Published: May 2018

BackgroundRadiomics or computer‐extracted texture features derived from MRI have been shown to help quantitatively characterize prostate cancer (PCa). Radiomics have not been explored depth in the context of predicting biochemical recurrence (BCR) of PCa.PurposeTo identify a set of radiomic features derived from pretreatment biparametric MRI (bpMRI) that may be predictive of PCa BCR.Study TypeRetrospective.SubjectsIn all, 120 PCa patients from two institutions, I1 and I2, partitioned into training set D1 (N = 70) from I1 and independent validation set D2 (N = 50) from I2. All patients were followed for ≥3 years.Sequence3T, T2‐weighted (T2WI) and apparent diffusion coefficient (ADC) maps derived from diffusion‐weighted sequences.AssessmentPCa regions of interest (ROIs) on T2WI were annotated by two experienced radiologists. Radiomic features from bpMRI (T2WI and ADC maps) were extracted from the ROIs. A machine‐learning classifier (CBCR) was trained with the best discriminating set of radiomic features to predict BCR (pBCR).Statistical TestsWilcoxon rank‐sum tests with P < 0.05 were considered statistically significant. Differences in BCR‐free survival at 3 years using pBCR was assessed using the Kaplan–Meier method and compared with Gleason Score (GS), PSA, and PIRADS‐v2.ResultsDistribution statistics of co‐occurrence of local anisotropic gradient orientation (CoLlAGe) and Haralick features from T2WI and ADC were associated with BCR (P < 0.05) on D1. CBCR predictions resulted in a mean AUC = 0.84 on D1 and AUC = 0.73 on D2. A significant difference in BCR‐free survival between the predicted classes (BCR + and BCR–) was observed (P = 0.02) on D2 compared to those obtained from GS (P = 0.8), PSA (P = 0.93) and PIRADS‐v2 (P = 0.23).Data ConclusionRadiomic features from pretreatment bpMRI can be predictive of PCa BCR after therapy and may help identify men who would benefit from adjuvant therapy.Level of Evidence: 4Technical Efficacy: Stage 5J. Magn. Reson. Imaging 2018;48:1626–1636
Design and analysis of multi‐stage PID controller for frequency control in an islanded micro‐grid using a novel hybrid whale optimization‐pattern search algorithm
Authors: Khadanga Rajendra Kumar , Padhy Sasmita , Panda Sidhartha , Kumar Amit 
Published: May 2018

AbstractIn this research work, a maiden approach is made for the frequency control in an islanded AC Microgrid (MG) by considering a hybrid Whale Optimization Algorithm and Pattern Search (hWOA‐PS) algorithm based multi‐stage Proportional Integrator Derivative controller. A MG may be formed by combining some of the unique assets like renewable energy sources, wind electricity era, and the sun electricity irradiation. Variation in any of the source influences the system frequency, and thus frequency control issue in MG is always a challenge for the researchers. In light of these difficulties, this paper considers a multi‐stage PID controller for the secondary frequency control of the islanded MGs, and a novel hWOA‐PS algorithm is used to tune the controller parameters. The proposed hybrid controller is inspected on a MG test system, and the robustness and execution are assessed by considering different disturbances and parametric variations. In order to show the effectiveness of the proposed hybrid algorithm based multi‐stage Proportional Integrator Derivative controller, it is being compared with some conventional controllers like Integral (I), Proportional Integral (PI), and Proportional Integral and Derivative (PID) controller.
Discrete mitochondrial aberrations in the spinal cord of sporadic ALS patients
Authors: Delic Vedad , Kurien Crupa , Cruz Josean , Zivkovic Sandra , Barretta Jennifer , Thomson Avery , Hennessey Daniel , Joseph Jaheem , Ehrhart Jared , Willing Alison E. , Bradshaw Patrick , Garbuzova‐Davis Svitlana 
Published: May 2018

AbstractAmyotrophic lateral sclerosis (ALS) is an adult onset neurodegenerative disease characterized by progressive motor neuron degeneration in the brain and spinal cord leading to muscle atrophy, paralysis, and death. Mitochondrial dysfunction is a major contributor to motor neuron degeneration associated with ALS progression. Mitochondrial abnormalities have been determined in spinal cords of animal disease models and ALS patients. However, molecular mechanisms leading to mitochondrial dysfunction in sporadic ALS (sALS) patients remain unclear. Also, segmental or regional variation in mitochondrial activity in the spinal cord has not been extensively examined in ALS. In our study, the activity of mitochondrial electron transport chain complex IV was examined in post‐mortem gray and white matter of the cervical and lumbar spinal cords from male and female sALS patients and controls. Mitochondrial distribution and density in spinal cord motor neurons, lateral funiculus, and capillaries in gray and white matter were analyzed by immunohistochemistry. Results showed that complex IV activity was significantly decreased only in gray matter in both cervical and lumbar spinal cords from ALS patients. In ALS cervical and lumbar spinal cords, significantly increased mitochondrial density and altered distribution were observed in motor neurons, lateral funiculus, and cervical white matter capillaries. Discrete decreased complex IV activity in addition to changes in mitochondria distribution and density determined in the spinal cord in sALS patients are novel findings. These explicit mitochondrial defects in the spinal cord may contribute to ALS pathogenesis and should be considered in development of therapeutic approaches for this disease.
Updating chromatographic predictions by accounting ageing for single and tandem columns
Authors: Alvarez‐Segura Tamara , Torres‐Lapasió José Ramón , García‐Alvarez‐Coque María Celia 
Published: May 2018

AbstractThe most efficient optimization methodologies in liquid chromatography are based on the modeling and prediction of the chromatographic behavior for each compound in the sample. However, when the column suffers some ageing after the modeling process, predictions may differ significantly from the actual separation. Repeating the modeling is especially troublesome when several columns are involved, as is the case of coupled columns. We propose a shortcut to correct the time and peak profiles in these situations, after evaluating the effects of ageing. The original models are corrected by introducing parameters accounting for column ageing, obtained using the data of a small subset of compounds from those used to model the brand‐new column. The ageing parameters are fitted from the discrepancies between the data predicted with the original retention models for the brand‐new column and the experimental data measured for the aged column. The approach was developed and tested to predict the chromatographic behavior of 15 sulfonamides, analyzed with individual and tandem columns, using isocratic and gradient elution. Chromatograms more in line with the aged column performance were predicted. The agreement between predictions and experimental data in the aged columns was excellent.
Clinical Contribution of Wrist and Hand Sonography: Pilot Study
Authors: Tagliafico Alberto , Bignotti Bianca , Rossi Federica , Rubino Maurizio , Civani Alessandro , Martinoli Carlo 
Published: May 2018

ObjectivesThe purpose of this study was to evaluate the clinical contribution of wrist and hand sonography.MethodsThis study was performed in a tertiary academic medical center. Institutional review board approval was obtained. Data collection was done retrospectively from January 2012 to December 2016 and prospectively from January 2017 to July 2017. The study included 112 consecutive patients (52 men and 60 women; mean age, 47 ± 16 years; range, 15–87 years). A total of 126 examinations were performed. All ultrasound examinations were done with high‐resolution probes with up‐to‐date protocols. The clinical contribution of wrist and hand sonography was assessed (ultrasound examinations contributive/noncontributive). Descriptive statistic and nonparametric tests were used.ResultsIn 96 of 126 (76%) examinations, sonography proved to be contributive, and in 30 of 126 (24%) examinations, sonography proved to be noncontributive. The contributive/noncontributive ratio was 3.2 (96/30). A total of 51 of 126 (40%) examinations were performed in patients with a history of previous trauma. Sonography proved to be significantly more contributive in a posttraumatic setting (chi‐square, 9.2; P = .0023).ConclusionWrist and hand sonography significantly influences the diagnostic and therapeutic path, especially in a posttraumatic setting.
Feeding strategies for the acquisition of high‐quality food sources in stream macroinvertebrates: Collecting, integrating, and mixed feeding
Authors: Guo Fen , Bunn Stuart E. , Brett Michael T. , Fry Brian , Hager Hannes , Ouyang Xiaoguang , Kainz Martin J. 
Published: May 2018

AbstractAquatic macroinvertebrates play an important functional role in energy transfer in food webs, linking basal food sources to upper trophic levels that include fish, birds, and humans. However, the trophic coupling of nutritional quality between macroinvertebrates and their food sources is still poorly understood. We conducted a field study in subalpine streams in Austria to investigate how the nutritional quality (measured by long‐chain polyunsaturated fatty acids, LC‐PUFAs) in macroinvertebrates changes relative to their basal food sources. Samples of macroinvertebrates, periphyton, and leaves were collected from 17 streams in July and October 2016 and their fatty acid (FA) composition was analyzed. Periphyton FA varied strongly with time and space, and their trophic effect on macroinvertebrate FA differed among functional feeding groups. The match between periphyton FA and macroinvertebrate FA decreased with increasing trophic levels, but LC‐PUFA content increased with each trophic step from periphyton to grazers and finally predators. Macroinvertebrates fed selectively on, assimilated, and/or actively controlled their LC‐PUFA, especially eicosapentaenoic acid (EPA, 20 : 5ω3) relative to their basal food sources in the face of spatial and temporal changes. Grazer FA profiles reflected periphyton FA with relatively good fidelity, and especially their EPA feeding strategy was primarily linked to periphyton FA variation across seasons. In contrast, shredders appeared to preferentially assimilate more EPA over other FA, which was determined by the availability of high‐quality food over seasons. Predators may more actively control their LC‐PUFA distribution with respect to different quality foods and showed less fidelity to the basal FA profiles in plants and prey. Overall, grazers and shredders showed relatively good fidelity to food FA profiles and performed as both “collectors” and “integrators” for LC‐PUFA requirements across seasons, while predators at higher trophic levels were more “integrators” with added metabolic complexity leading to somewhat more divergent FA profiles. These results are potentially applicable for other aquatic consumers in freshwater and marine ecosystems.
An autonomous, in situ light‐dark bottle device for determining community respiration and net community production
Authors: Collins James R. , Fucile Paul D. , McDonald Glenn , Ossolinski Justin E. , Keil Richard G. , Valdes James R. , Doney Scott C. , Van Mooy Benjamin A. S. 
Published: May 2018

AbstractWe describe a new, autonomous, incubation‐based instrument that is deployed in situ to determine rates of gross community respiration and net community production in marine and aquatic ecosystems. During deployments at a coastal pier and in the open ocean, the PHORCYS (PHOtosynthesis and Respiration Comparison‐Yielding System) captured dissolved oxygen fluxes over hourly timescales that were missed by traditional methods. The instrument uses fluorescence‐quenching optodes fitted into separate light and dark chambers; these are opened and closed with piston‐like actuators, allowing the instrument to make multiple, independent rate estimates in the course of each deployment. Consistent with other studies in which methods purporting to measure the same metabolic processes have yielded divergent results, respiration rate estimates from the PHORCYS were systematically higher than those calculated for the same waters using a traditional two‐point Winkler titration technique. However, PHORCYS estimates of gross respiration agreed generally with separate incubations in bottles fitted with optode sensor spots. An Appendix describes a new method for estimating uncertainties in metabolic rates calculated from continuous dissolved oxygen data. Multiple successful, unattended deployments of the PHORCYS represent a small step toward fully autonomous observations of community metabolism. Yet the persistence of unexplained disagreements among aquatic metabolic rate estimates—such as those we observed between rates calculated with the PHORCYS and two existing, widely accepted bottle‐based methods—suggests that a new community intercalibration effort is warranted to address lingering sources of error in these critical measurements.
The adsorption of dissolved organic carbon onto glass fiber filters and its effect on the measurement of particulate organic carbon: A laboratory and modeling exercise
Authors: Novak Michael G. , Cetinić Ivona , Chaves Joaquín E. , Mannino Antonio 
Published: May 2018

AbstractParticulate organic carbon (POC) represents a small portion of total carbon in the ocean. However, it plays a large role in the turnover of organic matter through the biological pump and other processes. Early on since the development of the POC measurement technique in the 1960s, it was known that dissolved organic carbon (DOC) adsorbs and is retained both on and in the filter. That retained DOC is measured as if it was part of the particulate fraction, an artifact that can cause significant overestimates of POC concentration. We set out to address the long‐standing question of whether the magnitude of the DOC adsorption is affected by the quantity and quality of the dissolved organic matter in the sample. However, our results precluded an unequivocal answer to that question; nevertheless, the experimental data generated did allow us to develop and test predictive models that relate the mass of carbon adsorbed to the volume of sample filtered. The results indicate that the uptake of DOC can be predicted using an exponential model and that a saturation point is approached when approximately a half‐liter of water is filtered. This model can be a valuable tool for correcting existing POC data sets that did not account for DOC adsorption. Nonetheless, this approach should not be regarded as a substitute for collecting in situ filter blanks in parallel with POC samples to properly correct for this artifact.
Folate‐Conjugated and Dual Stimuli‐Responsive Mixed Micelles Loading Indocyanine Green for Photothermal and Photodynamic Therapy
Authors: Chien Yu‐Ying , Wang Tung‐Yun , Liao Po‐Wen , Wu Wen‐Chung , Chen Ching ‐Yi 
Published: May 2018

AbstractA folic acid targeted mixed micelle system based on co‐assembly of poly(ε‐caprolactone)‐b‐poly(methoxytri(ethylene glycol) methacrylate‐co‐N‐(2‐methacrylamido)ethyl folatic amide) and poly(ε‐caprolactone)‐b‐poly(diethylene glycol monomethyl ether methacrylate) is developed to encapsulate indocyanine green (ICG) for photothermal therapy and photodynamic therapy. In this study, the use of folic acid is not only for specific cancer cell recognition, but also in virtue of the carboxylic acid on folic acid to regulate the pH‐dependent thermal phase transition of polymeric micelles for controlled drug release. The prepared ICG‐loaded mixed micelles possess several superior properties such as a preferable thermoresponsive behavior, excellent storage stability, and good local hyperthermia and reactive oxygen species generation under near‐infrared (NIR) irradiation. The photototoxicity induced by the ICG‐loaded micelles has efficiently suppressed the growth of HeLa cells (folate receptor positive cells) under NIR irradiation compared to that of HT‐29, which has low folate receptor expression. Hence, this new type of mixed micelles with excellent features could be a promising delivery system for controlled drug release, effective cancer cell targeting, and photoactivated therapy.