bluuebunny/crossref_metadata_2025 huggingface dataset:
Blurred time resolution of tooth dentin serial sections
Authors: Tsutaya Takumi
Published: September 2020

Objectives

The growth of tooth dentin is incremental, so its formation represents a dietary record in early life. With archeological skeletons, applying sequential stable isotope analysis to the horizontal sections of tooth dentin has revealed weaning patterns and dietary changes that took place during childhood. However, the assignment of ages to dentin serial sections (DSSs) is problematic due to the changing extension rate and oblique growth layers of dentin, and these effects have not been quantified. This study presents a mathematical model for investigating the corresponding age range of the horizontal DSSs of human permanent incisors, canines, and molars.

Methods

Parameters describing the tooth dentin microstructure were taken from previous studies, and dentin growth patterns were modeled. The model was implemented as the R package MDSS.

Results

The developed model shows that the true corresponding age of the sections differed by a few years on average from the estimated age with equal temporal divisions, that the model gave values extending across a wide range, and that these differences become large for sections formed at older ages. The stable isotope ratio of the sections presented an aggregate representation of possibly complex dietary changes across a few years, and dietary changes over short times, such as several months, could not be accurately reconstructed even when using a finer horizontal sectioning method.

Conclusions

These results demonstrate that DSSs correspond to an unexpectedly wider (i.e., three to four times) and different (i.e., −2 to 0.5 years on average) age range than previously assumed and that complicated patterns of dietary change blur in the isotopic trajectory of the sections. Alternative experimental methods, such as imaging‐assisted oblique sampling, should be used to retrieve an accurate and precise sequential dietary record from tooth dentin.
A study on nonlinear model predictive control for helicopter/turboshaft engine with variable rotor speed based on piecewise objective function
Authors: Wang Yong , Peng Yerong , Xi Zhihua , Zhang Haibo
Published: September 2020

In order to obtain the high‐quality fast response control for helicopter/turboshaft engine with variable rotor speed, a nonlinear model predictive control (NMPC) method based on piecewise objective function is proposed. The piecewise objective function takes into account both the control index of power turbine speed and the rotor dynamics of engine output shaft, which optimizes the transient overshoot and sag of the power turbine speed caused by torques mismatch during variable rotor speed from the root. The results show that compared with conventional MPC method with single objective function only involving the control index of power turbine speed, the novel NMPC method proposed can reduce the overshoot or sag of the power turbine speed by more than 30% during variable rotor speed, which possesses superior control effect of turboshaft engine without losing real‐time performance.
Impact of complete surgical resection on outcome in aggressive non‐Hodgkin lymphoma treated with immunochemotherapy
Authors: Schmitz Christine , Rekowski Jan , Müller Stefan P. , Farsijani Navid , Hertenstein Bernd , Franzius Christiane , von Verschuer Ulla , La Rosée Paul , Freesmeyer Martin , Wilop Stefan , Krohn Thomas , Raghavachar Aruna , Ganser Arnold , Bengel Frank M. , Prange‐Krex Gabriele , Kroschinsky Frank , Kotzerke Jörg , Giagounidis Aristoteles , Dührsen Ulrich , Hüttmann Andreas
Published: September 2020

Background

Surgical resection is considered to be of purely diagnostic value in aggressive lymphoma. Evidence for an impact on outcome is scant and restricted to retrospective observations.

Methods

In the “Positron Emission Tomography‐guided Therapy of Aggressive non‐Hodgkin Lymphomas” (PETAL) trial, patients with a negative baseline positron emission tomography (PET) scan were documented in a prospective observational substudy. Baseline PET‐negative patients with the absence of lymph node enlargement on computed tomography and a negative bone marrow biopsy were considered to have undergone complete lymphoma resection.

Results

Eighty‐two of 1,041 patients (7.9%) had a negative baseline PET scan, and 67 were included in this analysis. All were treated with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP), plus rituximab for CD20‐positive lymphomas. Among 52 patients with diffuse large B‐cell lymphoma (DLBCL), 48 had completely resected disease. Their outcome tended to be better than that of 115 baseline PET‐positive stage I DLBCL patients treated in the main part of the PETAL trial (2‐year progression‐free survival 92.7% [95% confidence interval 84.7‐100] versus 88.4% [82.5‐94.3], P = .056; 2‐year overall survival 92.7% [84.7‐100] versus 93.7% [89.2‐98.2], P = .176), but this was restricted to patients below the age of 60 years (2‐year progression‐free survival 100% versus 92.2% [84.8‐99.6], P = .031; 2‐year overall survival 100% versus 95.9% [90.2‐100], P = .075). In peripheral T‐cell lymphoma, eight of 11 patients had completely resected disease. In contrast to DLBCL, complete resection was not associated with improved outcome compared to the control.

Conclusion

Young patients with early stage DLBCL may benefit from complete lymphoma resection prior to immunochemotherapy.
Hepatitis B virus core–related antigen is useful for surveillance of hepatocellular carcinoma recurrence in a patient with occult hepatitis B virus infection: Case report
Authors: Yokoyama Keiji , Yamauchi Eri , Uchida Yotaro , Kitaguchi Takanori , Fukuda Hiromi , Yamauchi Ryo , Tsuchiya Naoaki , Umeda Kaoru , Takata Kazuhide , Tanaka Takashi , Inomata Shinjiro , Morihara Daisuke , Takeyama Yasuaki , Shakado Satoshi , Sakisaka Shotaro , Hirai Fumihito
Published: September 2020

Serum HBV core–related antigen (HBcrAg) is useful for detecting HCC in patients with occult HBV infection. Surveillance for HCC is needed in patients who are positive for HBcrAg, even if they are negative for HBsAg and HBV DNA.
Immunopharmacology and Quantitative Analysis of Tyrosine Kinase Signaling
Authors: Brian Ben F. , Guerrero Candace R. , Freedman Tanya S.
Published: September 2020

In this article we describe the use of pharmacological and genetic tools coupled with immunoblotting (Western blotting) and targeted mass spectrometry to quantify immune signaling and cell activation mediated by tyrosine kinases. Transfer of the ATP γ phosphate to a protein tyrosine residue activates signaling cascades regulating the differentiation, survival, and effector functions of all cells, with unique roles in immune antigen receptor, polarization, and other signaling pathways. Defining the substrates and scaffolding interactions of tyrosine kinases is critical for revealing and therapeutically manipulating mechanisms of immune regulation. Quantitative analysis of the amplitude and kinetics of these effects is becoming ever more accessible experimentally and increasingly important for predicting complex downstream effects of therapeutics and for building computational models. Secondarily, quantitative analysis is increasingly expected by reviewers and journal editors, and statistical analysis of biological replicates can bolster claims of experimental rigor and reproducibility. Here we outline methods for perturbing tyrosine kinase activity in cells and quantifying protein phosphorylation in lysates and immunoprecipitates. The immunoblotting techniques are a guide to probing the dynamics of protein abundance, protein–protein interactions, and changes in post‐translational modification. Immunoprecipitated protein complexes can also be subjected to targeted mass spectrometry to probe novel sites of modification and multiply modified or understudied proteins that cannot be resolved by immunoblotting. Together, these protocols form a framework for identifying the unique contributions of tyrosine kinases to cell activation and elucidating the mechanisms governing immune cell regulation in health and disease. © 2020 The Authors.

Basic Protocol 1: Quantifying protein phosphorylation via immunoblotting and near‐infrared imaging

Alternate Protocol: Visualizing immunoblots using chemiluminescence

Basic Protocol 2: Enriching target proteins and isolation of protein complexes by immunoprecipitation

Support Protocol: Covalent conjugation of antibodies to functionalized beads

Basic Protocol 3: Quantifying proteins and post‐translational modifications by targeted mass spectrometry
Pharmacokinetics and Drug‐Drug Interactions of Isoniazid and Efavirenz in Pregnant Women Living With HIV in High TB Incidence Settings: Importance of Genotyping
Authors: Gausi Kamunkhwala , Wiesner Lubbe , Norman Jennifer , Wallis Carole L. , Onyango‐Makumbi Carolyne , Chipato Tsungai , Haas David W. , Browning Renee , Chakhtoura Nahida , Montepiedra Grace , Aaron Lisa , McCarthy Katie , Bradford Sarah , Vhembo Tichaona , Stranix‐Chibanda Lynda , Masheto Gaerolwe R. , Violari Avy , Mmbaga Blandina T. , Aurpibul Linda , Bhosale Ramesh , Nevrekhar Neetal , Rouzier Vanessa , Kabugho Enid , Mutambanengwe Mercy , Chanaiwa Vongai , Nyati Mandisa , Mhembere Tsungai , Tongprasert Fuanglada , Hesseling Anneke , Shin Katherine , Zimmer Bonnie , Costello Diane , Jean‐Philippe Patrick , Sterling Timothy R. , Theron Gerhard , Weinberg Adriana , Gupta Amita , Denti Paolo ,   IMPAACT P1078 (TB APPRISE) Study Group Team
Published: September 2020

The World Health Organization guidelines recommend that individuals living with HIV receive ≥ 6 months of isoniazid preventive therapy, including pregnant women. Yet, plasma isoniazid exposure during pregnancy, in the antiretroviral therapy era, has not been well‐described. We investigated pregnancy‐induced and pharmacogenetic‐associated pharmacokinetic changes and drug‐drug interactions between isoniazid and efavirenz in pregnant women. Eight hundred forty‐seven women received isoniazid for 28 weeks, either during pregnancy or at 12 weeks postpartum, and 786 women received efavirenz. After adjusting for NAT2 and CYP2B6 genotype and weight, pregnancy increased isoniazid and efavirenz clearance by 26% and 15%, respectively. Isoniazid decreased efavirenz clearance by 7% in CYP2B6 normal metabolizers and 13% in slow and intermediate metabolizers. Overall, both isoniazid and efavirenz exposures were reduced during pregnancy, but the main determinants of drug concentration were NAT2 and CYP2B6 genotypes, which resulted in a five‐fold difference for both drugs between rapid and slow metabolizers.
Effect of arbitrary temperature degeneracy and ion magnetization on shear Alfven waves in electron‐positron‐ion plasmas
Authors: Safdar A. , Mushtaq A. , Ikram M. , Ahmad Zulfiqar , Batool Syeda R.
Published: September 2020

Linear properties of low‐frequency electromagnetic shear Alfven waves (SAWs) are studied in quantum electron‐positron‐ion plasmas with effect of arbitrary temperature degeneracy for magnetized () and unmagnetized ( ) ions by using the quantum hydrodynamic model. Dispersion relations are derived for nearly degenerate () and nearly non‐degenerate () plasmas. Bohm potential due to density correlation and temperature degeneracy due to Fermi–Dirac statistics of electron–positron, and their effects on the dispersion of SAWs are studied in detail both analytically and numerically. The relevance of the work regarding dense astrophysical plasmas is highlighted.
Person‐Oriented Research Ethics to Address the Needs of Participants on the Autism Spectrum
Authors: Cascio M. Ariel , Weiss Jonathan A. , Racine Eric
Published: September 2020

Research ethics scholarship often attends to vulnerability. People with autism may be vulnerable in research, but are also vulnerable to unjust exclusion from participation. Addressing the needs of participants with autism can facilitate inclusion and honor the bioethics principle of respect for persons while accounting for risk and vulnerability. Drawing from a review of the literature and informed by a moral deliberation process involving a task force of stakeholders (including autistic people and parents of autistic people), we use the model of person‐oriented research ethics to identify several practical strategies researchers can use to address these needs and foster inclusion. Strategies include using multiple means of communication, addressing the sensory environment, preparing participants in advance, and accounting for social context. These practical strategies are not just methodological or design choices; they are inherently related to ethical issues. Method and design choices fulfill ethical aspirations by facilitating inclusion, reducing discomfort, and focusing on individuals.
Crosstalk between coronavirus disease 2019 and cardiovascular disease and its treatment
Authors: Ye Qing , Lu Dezhao , Shang Shiqiang , Fu Junfen , Gong Fangqi , Shu Qiang , Mao Jianhua
Published: September 2020

People with cardiovascular disease (CVD) often contract coronavirus disease 2019 (COVID‐19). However, the interaction between COVID‐19 and CVD is unclear. In this systematic review, the available evidence for the crosstalk between COVID‐19 and CVD and its treatment was analysed. A search was performed in the electronic databases MEDLINE and EMBASE. Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infects human cells via angiotensin‐converting enzyme 2. SARS‐CoV‐2 can cause CVD by inducing cytokine storms, creating an imbalance in the oxygen supply and demand and disrupting the renin–angiotensin–aldosterone system; SARS‐CoV‐2 infection can also lead to the development of CVD through the side effects of therapeutic drugs, psychological factors, and aggravation of underlying CVD. The most common CVDs caused by SARS‐CoV‐2 infection are acute myocardial injury, arrhythmia, and heart failure. Studies have found that there is an interaction between COVID‐19 and CVD. Underlying CVD is associated with a high risk of mortality in patients with COVID‐19. SARS‐CoV‐2 infection can also cause new‐onset CVD. Clinicians need to pay close attention to cardiovascular complications during the diagnosis and treatment of patients with COVID‐19 to reduce patient mortality.
Toxicities of Neonicotinoid-Containing Pesticide Mixtures on Nontarget Organisms
Authors: Zhao Guo-Ping , Yang Fang-Wei , Li Jin-Wang , Xing Han-Zhu , Ren Fa-Zheng , Pang Guo-Fang , Li Yi-Xuan
Published: September 2020

Neonicotinoids are a widely used class of pesticides. Co-exposure to neonicotinoids and other classes of pesticides can exert potentiating or synergistic effects, and these mixtures have been detected in human bodily fluids. The present review summarizes studies into the effects of neonicotinoid-containing pesticide mixtures on humans and other nontarget organisms. Exposure to these mixtures has been reported to result in reproductive and hormonal toxicity, genotoxicity, neurotoxicity, hepatotoxicity, and immunotoxicity in vertebrates. Mortality of pollinators and toxicity in other organisms has also been reported. The underlying mechanism of pesticide mixture toxicity may be associated with impairment of cytochrome 450 enzymes, which are involved in metabolizing pesticides. However, a comprehensive explanation of the adverse effects of neonicotinoid-containing pesticide mixtures is still required so that effective prevention and control measures can be formulated. Environ Toxicol Chem 2020;39:1884–1893. © 2020 SETAC
Higher psychogeriatric admissions in COVID‐19 than in severe acute respiratory syndrome
Authors: Lee Allen T. C. , Mo Flora Y. M. , Lam Linda C. W.
Published: September 2020

Objectives

To examine whether psychogeriatric admissions increased after COVID‐19, independent of seasonal variation; whether the increase was comparable with that seen in severe acute respiratory syndrome (SARS); and which factors were associated with such increase.

Methods

All psychiatric admissions aged 65 or older in the 3 months before and after COVID‐19 (from November 2019 to April 2020), in the previous 2 years (from November 2017 to April 2018 and from November 2018 to April 2019), and in the year of SARS (from November 2002 to April 2003) in a major gazette inpatient psychiatric unit in Hong Kong, which serves a catchment population of 1.4 million, were anonymously reviewed. The number of psychogeriatric admissions between different timeframes was compared, and factors that might explain the increase in admissions following COVID‐19 were examined.

Results

Psychogeriatric admissions increased by 21.4% following the COVID‐19 outbreak. This increase was not explained by seasonal variation and was greater and lasted longer than that in SARS. A rising trend in admissions for older adults living in residential care homes was observed. The increase in admissions was associated with fewer outpatient attendance, fewer home visits by nurses, and more older adults with dementia requiring inpatient care.

Conclusions

Our findings highlight the impact of COVID‐19 on older adults' mental health, greater demand for inpatient psychogeriatric services in COVID‐19 than in SARS, and the importance of maintaining support for community‐living older adults, in particular those with dementia, and their caregivers in reducing the needs for inpatient psychiatric treatment during the pandemic.

Clinicaltrials.gov # ChiCTR2000033317
Consolidated framework for advancing implementation science for the implementation process and adherence assessment of a non‐pharmacological delirium prevention program
Authors: Garrido Maricel A. , Alvarez Evelyn A. , Ponce Daniela P. , Salech Felipe , Tobar Daniel I. , Tobar Eduardo A.
Published: September 2020

Objective

To evaluate the contribution of applying the theoretical framework of implementation science for adherence to non‐pharmacological interventions to prevent delirium.

Methods

A quasi‐experimental prospective design was conducted from March 2017 to October 2018 in a teaching hospital. Participants included 149 healthcare staff and 72 elderly inpatients. A non‐pharmacological delirium prevention program was designed, applied and evaluated in accordance with the consolidated framework for advancing implementation research (CFIR). The primary outcome was the global adherence rate to 12 predefined indicators, comparing measurements at baseline (O1), after training (O2) and at a 6‐month follow‐up (O3) assessed by an external reviewer. Staff knowledge and beliefs about delirium were assessed using a validated tool, and delirium incidence was evaluated using the confusion assessment method.

Results

Overall adherence increased from 58.2% (O1) to 77.9% (O2) and 75.6% (O3) (O2 vs. O1: p < 0.001 and O3 vs. O1: p < 0.001). Staff perceptions regarding implementation of non‐pharmacological interventions increased from 74.8% to 81.9% (p = 0.004). Delirium incidence was non‐significantly reduced from 20% (O1) to 16% (O3) (p = 0.99).

Conclusions

Implementation of a delirium prevention program using a CFIR model was useful in improving adherence to activities included in this program, as well as improving the knowledge and beliefs regarding delirium by healthcare workers. The impact of this implementation strategy on the incidence of delirium should be evaluated in a larger scale multicenter trial.
Theoretical predictions on pentaerythritol tetranitrate‐based high energy density compounds
Authors: Lu Meng , Zhu Weihua
Published: September 2020

A novel family of pentaerythritol tetranitrate (PETN) derivatives based parent PETN skeleton were designed by introducing two energetic groups –NF2 and –NO2. Their electronic structure, heats of formation, detonation properties, impact sensitivity, and thermal stability were investigated by using density functional theory. The findings reveal that most of the title compounds have good detonation performance. The –NF2 group played an important role in improving the densities, heats of detonation, and detonation properties of the designed molecules. The values of h50 for almost all the PETN derivatives are higher than that of octahydro‐1,3,5,7‐tetranitro‐1,3,5,7‐tetrazocine. An analysis of bond dissociation energy suggests that the N‐NO2 bond tends to be a trigger bond in thermal decomposition. Taking both detonation properties and thermal stabilities into consideration, the three compounds may be selected as potential high‐energy‐density compounds.
Numerical modeling of two microwave sensors for biomedical applications
Authors: Bao Xiue , Crupi Giovanni , Ocket Ilja , Bao Juncheng , Ceyssens Frederik , Kraft Michael , Nauwelaers Bart , Schreurs Dominique
Published: September 2020

The purpose of this invited paper is to give readers a critical and comprehensive overview on how to extract dielectric properties of a bioliquid within a broad frequency range. Two sensors are used in the paper to characterize saline solutions by measuring the broadband complex permittivity. The two sensors are based on transmission line and interdigital electrodes designed for low‐ and high‐ frequency measurements, respectively, on the basis of the coplanar waveguide structure due to its convenience of fabrication and integration with microfluidic structures for liquid measurements. Different from traditional work where the finite element simulation method is used, the characterization theories of the two sensors are built based on a numerical modeling procedure, which can dramatically increase the device design efficiency, taking just a few seconds. Differently from the finite element method, the proposed numerical analysis utilizes a conformal mapping technique for both sensors. The characterization theories of the two sensors are validated by measuring de‐ionized water. The platform is finally used to measure 0.1 and 0.5 mol/L saline solutions within a broadband frequency range going from 10 up to 50 GHz, with the repeatability error within 5%.
Surgical Implantation of Acoustic Tags in American Shad to Resolve Riverine and Marine Restoration Challenges
Authors: Gahagan Benjamin I. , Bailey Michael M.
Published: September 2020

A variety of data needs challenge the successful restoration and management of alosine populations, including information on the migration, mortality, behavior, demographic rates, and distribution of fish, both in riverine and marine environments. Radiotelemetry with gastric-implanted transmitters has typically been used to answer some of these questions; however, observing alosines over extended periods and in the marine environment has remained beyond the limitations of this technology and implantation technique. To address these issues, we conducted an acoustic telemetry study on American Shad Alosa sapidissima by using surgical implantation methods. We tagged fish during 2015 (n =46) and 2016 (n =52) in the Charles River, Massachusetts, an urbanized watershed where American Shad were believed to be extirpated prior to restoration efforts beginning in 2006. Surgical implantation produced rates of in-river mortality (40% overall) and posttagging fallback (39% overall) that were comparable to those from traditionally used gastric implantation methods. Data from American Shad that were retained for statistical analyses (n =59) demonstrated that Watertown Dam (at river kilometer 14.3) impeded upstream migration and that New Boston Dam and Locks (at the mouth of the river) delayed postspawn emigration from the river. In total, 49 American Shad were detected outside of the Charles River. The distribution and low number of total detections, despite a large number of nearshore arrays, suggest that American Shad occupy waters farther offshore during their marine phase. American Shad were detected as overwintering on the Scotian Shelf (n =5) and the Mid-Atlantic Bight (n =1). In 2017, 10 of the individuals that were tagged in 2016 returned to spawn, providing the first reported data on total migration timing and migratory behavior free of handling effects. Surgical implantation of acoustic telemetry tags is an effective method that can provide necessary and previously unattainable data on a species of conservation need.
Novel variants in POLH and TREM2 genes associated with a complex phenotype of xeroderma pigmentosum variant type and early‐onset dementia
Authors: Soares Izadora Fonseca Zaiden , Christofolini Denise Maria , Silva Lis Gomes , Feder David , de Siqueira Carvalho Alzira Alves
Published: September 2020

Background

Xeroderma pigmentosum (XP) is a rare, genetically heterogeneous, autosomal recessive disorder caused by defects in the genes involved in repairing DNA damaged by ultraviolet radiation. These defects lead to a propensity to develop skin cancer at early ages as a hallmark, and progressive neurological degeneration can be observed in around 25% of patients. Eight clinically heterogeneous groups have been identified so far (XPA to XPG and XPV). Xeroderma pigmentosum variant type (XPV) is associated with pathogenic variants in POLH on chromosome 6, and no neurological dysfunction has been seen in these cases. However, on the same chromosome, it has been shown that TREM2 is associated with some types of dementia, particularly in patients with a behavioral variant frontotemporal phenotype.

Methods

Gene mutational analysis was performed by whole‐exome sequencing.

Results

We report a case of a Caucasian woman with XP that developed behavioral and cognitive impairment at age 37. Whole‐exome sequencing identified novel homozygous variants in POLH c.638C>G (p.Ser213*) and TREM2 c.154C>T (p.Arg52Cys), classifying the patient as XPV and suggesting that her frontotemporal dementia phenotype could be related to the variant in TREM2.

Conclusion

This paper describes a rare case of a patient with two novel variants in the same chromosome associated with XPV and early‐onset dementia.
Influence of phosphate concentration on amine, amide, and hydroxyl CEST contrast
Authors: Yao Jingwen , Wang Chencai , Ellingson Benjamin M.
Published: September 2020

Purpose

To evaluate the influence of phosphate on amine, amide, and hydroxyl CEST contrast using Bloch‐McConnell simulations applied to physical phantom data.

Methods

Phantom solutions of 4 representative metabolites with exchangeable protons—glycine (α‐amine protons), Cr (η‐amine protons), egg white protein (amide protons), and glucose (hydroxyl protons)—were prepared at different pH levels (5.6 to 8.9) and phosphate concentrations (5 to 80 mM). CEST images of the phantom were collected with CEST‐EPI sequence at 3 tesla. The CEST data were then fitted to full Bloch‐McConnell equation simulations to estimate the exchange rate constants. With the fitted parameters, simulations were performed to evaluate the intracellular and extracellular contributions of CEST signals in normal brain tissue and brain tumors, as well as in dynamic glucose‐enhanced experiments.

Results

The exchange rates of α‐amine and hydroxyl protons were found to be highly dependent on both pH and phosphate concentrations, whereas the exchange rates of η‐amine and amide protons were pH‐dependent, albeit not catalyzed by phosphate. With phosphate being predominantly intracellular, CEST contrast of α‐amine exhibited a higher sensitivity to changes in the extracellular microenvironment. Simulations of dynamic glucose‐enhanced signals demonstrated that the contrast between normal and tumor tissue was mostly due to the extracellular CEST effect.

Conclusion

The proton exchange rates in some metabolites can be greatly catalyzed by the presence of phosphate at physiological concentrations, which substantially alters the CEST contrast. Catalytic agents should be considered as confounding factors in future CEST‐MRI research. This new dimension may also benefit the development of novel phosphate‐sensitive imaging methods.
Fusing acceleration and saturation techniques with wave amplitude labeling of time‐shifted zeniths MR elastography
Authors: Wang Hui , Pednekar Amol , Tkach Jean A. , Bridgewater Kaley R. , Trout Andrew T. , Dillman Jonathan R. , Dumoulin Charles L.
Published: September 2020

Purpose

To design a new 2D gradient recalled echo MR elastography (MRE) pulse sequence with inflow saturation for measuring liver stiffness in half the breath‐hold time compared to standard of care (SC) 2D GRE MRE sequences.

Methods

FASTWALTZ (fusing acceleration and saturation techniques with wave amplitude labeling of time‐shifted zeniths) MRE employs an interleaved dual TR strategy with wave amplitude labeling and compressed SENSE undersampling to reduce breath‐hold time while incorporating inflow saturation to suppress flow artifacts. The sequence was implemented and compared with SC MRE both in phantoms and in vivo in 5 asymptomatic volunteers. Stiffness values, region of interest size, and breath‐hold times were compared between sequences.

Results

Stiffness values were comparable between FASTWALTZ and SC MRE for both phantoms and in‐vivo data. In volunteers, the group mean stiffness values at 60 Hz and region of interest size were 1.96 ± 0.30 kilopascals and 2279 ± 516 mm2 for SC MRE, and 1.95 ± 0.29 kilopascals and 2061 ± 464 mm2 for FASTWALTZ. Breath‐hold duration for FASTWALTZ was 6.3 s compared to 13.3 s for SC MRE.

Conclusion

FASTWALTZ provides comparable stiffness values in half the breath‐hold time compared to SC MRE and may have clinical benefits in patients with limited breath‐holding capacity.
Blood oxygenation level‐dependent cardiovascular magnetic resonance of the skeletal muscle in healthy adults: Different paradigms for provoking signal alterations
Authors: Suo Shiteng , Tang Hui , Lu Qing , Zhang Lan , Ni Qihong , Cao Mengqiu , Chen Zengai , Zhao Huilin , Sun Beibei , Xu Jianrong
Published: September 2020

Purpose

Stress blood oxygenation level‐dependent (BOLD) cardiovascular magnetic resonance allows for quantitative evaluation of blood flow reserve in skeletal muscles. This study aimed to prospectively compare three commonly used skeletal BOLD cardiovascular magnetic resonance paradigms in healthy adults: gas inhalation, cuff compression‐induced ischemia and postocclusive reactive hyperemia, and exercise.

Methods

Twelve young (22 ± 0.9 years) and 10 elderly (58 ± 5.0 years) healthy subjects underwent BOLD cardiovascular magnetic resonance under the three paradigms. signal intensity time curves were generated and quantitative parameters were calculated. Meanwhile, stress transcutaneous oxygen pressure measurements were obtained as comparison. Measurement reproducibility was assessed with intraclass correlation coefficients. Differences in the BOLD variation, the correlation with transcutaneous oxygen pressure, and the age‐related change between paradigms were statistically analyzed.

Results

Minimum ischemic value and maximum hyperemic peak value showed the highest interobserver and interscan reproducibilities (intraclass correlation coefficient >0.90). The plantar dorsiflexion exercise paradigm elicited the largest BOLD variation (15.48% ± 10.56%), followed by ischemia (8.30% ± 6.33%). Negligible to weak changes were observed during gas inhalation. Correlations with transcutaneous oxygen pressure measurements were found in the ischemic phase (r = 0.966; P < .001) and in the postexercise phase (r = −0.936; P < .001). Minimum ischemic value, maximum hyperemic peak value, maximum postexercise value, and slope of postexercise signal decay showed significant differences between young and elderly subjects (P < .01).

Conclusion

Ischemia and reactive hyperemia have superior reproducibility, and exercise could induce the largest variation. Key parameters from the two paradigms show age‐related differences.
Separation of fluid and solid shear wave fields and quantification of coupling density by magnetic resonance poroelastography
Authors: Lilaj Ledia , Fischer Thomas , Guo Jing , Braun Jürgen , Sack Ingolf , Hirsch Sebastian
Published: September 2020

Purpose

Biological soft tissues often have a porous architecture comprising fluid and solid compartments. Upon displacement through physiological or externally induced motion, the relative motion of these compartments depends on poroelastic parameters, such as coupling density () and tissue porosity. This study introduces inversion recovery MR elastography (IR‐MRE) (1) to quantify porosity defined as fluid volume over total volume, (2) to separate externally induced shear strain fields of fluid and solid compartments, and (3) to quantify coupling density assuming a biphasic behavior of in vivo brain tissue.

Theory and Methods

Porosity was measured in eight tofu phantoms and gray matter (GM) and white matter (WM) of 21 healthy volunteers. Porosity of tofu was compared to values obtained by fluid draining and microscopy. Solid and fluid shear‐strain amplitudes and were estimated both in phantoms and in in vivo brain.

Results

T1‐based measurement of tofu porosity agreed well with reference values (R = 0.99, P < .01). Brain tissue porosity was 0.14 ± 0.02 in GM and 0.05 ± 0.01 in WM (P < .001). Fluid shear strain was found to be phase‐locked with solid shear strain but had lower amplitudes in both tofu phantoms and brain tissue (P < .05). In accordance with theory, tofu and brain were negative.

Conclusion

IR‐MRE allowed for the first time separation of shear strain fields of solid and fluid compartments for measuring coupling density according to the biphasic theory of poroelasticity. Thus, IR‐MRE opens horizons for poroelastography‐derived imaging markers that can be used in basic research and diagnostic applications.
Brand Reputation, Brand Experience, and Electronic Word of Mouth Toward Smartphone: Investigating the Mediating Role of Brand Love
Authors: Iqbal Jawad , Malik Mehak , Yousaf Saira , Yaqub Rana Muhammad Shahid
Published: September 2020

The basic purpose of this study is to understand the impact of brand experience, brand reputation, and brand love on electronic word of mouth (eWOM) in the Smartphone industry. The primary data includes 312 valid responses collected through a survey conducted in Bahawalpur city of Punjab Province, Pakistan. Findings have shown that Smartphone brand reputation and brand experience is positively associated with consumers' brand love and eWOM. Moreover, consumers' brand love has been found as a mediator in the relationships between (a) brand reputation and eWOM and (b) brand experience and eWOM. This study will increase awareness among the managers and other policy makers about the importance of brand love and other factors in getting eWOM particularly in Smartphone industry and generally in others. Limitations of the study, directions for future research, and policy guidelines are discussed.
Ribosomal protein L5 mediated inhibition of c‐Myc is critically involved in sanggenon G induced apoptosis in non‐small lung cancer cells
Authors: Park Ji Eon , Jung Ji Hoon , Lee Hyo‐Jung , Sim Deok Yong , Im Eunji , Park Woon Yi , Shim Bum Sang , Ko Seong‐Gyu , Kim Sung‐Hoon
Published: September 2020

Though Sanggenon G (SanG) from root bark of Morus alba was known to exhibit anti‐oxidant and anti‐depressant effects, its underlying mechanisms still remain unclear. Herein SanG reduced the viability of A549 and H1299 non‐small lung cancer cells (NSCLCs). Also, SanG increased sub‐G1 population via inhibition of cyclin D1, cyclin E, CDK2, CDK4 and Bcl‐2, cleavages of poly (ADP‐ribose) polymerase (PARP) and caspase‐3 in A549 and H1299 cells. Of note, SanG effectively inhibited c‐Myc expression by activating ribosomal protein L5 (RPL5) and reducing c‐Myc stability even in the presence of cycloheximide and 20% serum in A549 cells. Furthermore, SanG enhanced the apoptotic effect with doxorubicin in A549 cells. Taken together, our results for the first time provide novel evidence that SanG suppresses proliferation and induces apoptosis via caspase‐3 activation and RPL5 mediated inhibition of c‐Myc with combinational potential with doxorubicin.
Two‐layer model of equipment fault propagation in manufacturing system
Authors: Hou Zhi , Yu Zhonghua
Published: September 2020

Equipment fault is a major factor that affects the reliability of manufacturing systems. Fault source identification and propagation path search are primary means to reduce and eliminate equipment faults. To this end, this paper proposed a two‐layer model of equipment fault propagation in a manufacturing system. One layer, modeled by a small‐world network, is a network of parts for a single equipment device. The other, represented by the production relationships of the manufacturing process, is a network of equipment devices for a manufacturing system. Hence, the propagation path of an equipment fault is divided into physical propagation inside a single equipment device and flow propagation within the manufacturing process. The intensity of physical propagation is given by the product of the fault load and the propagation probability between fault nodes within a single equipment device, whereas the flow propagation intensity is equivalent to the yield loss of the manufacturing system due to equipment fault. Therefore, the total intensity of fault propagation in a manufacturing system is given by the product of these two intensities. Subsequently, the ant colony algorithm is used to find the propagation paths with the maximum intensity. Finally, the proposed method is verified using an example of a camshaft manufacturing system.
Predicting the Cardiac Troponin I (cTnl) Aptamer/Methylene Blue Configuration Using Computational Modeling Studies: A Screening Search Method for Constructing Aptasensors
Authors: Mokhtari Zaynab , Khajehsharifi Habibollah , Hashemnia Sedigheh , Shahrokhian Saeed
Published: September 2020

Acute Myocardial Infarction (AMI) is the most common cause of mortality, and cardiac troponin I (cTnI) is the gold standard for AMI diagnosis. Some aptamers have been reported to detect cTnI, but there is rarely any structural information on their binding with cTnI. There are many studies involving electrochemical aptasensors with methylene blue (MB) as a redox indicator that does not provide any significant new information. Our study, however, involves the computational modeling of the complexes of a documented 40‐mer ssDNA‐cTnI aptamer with its target and MB. Here, MB was used as a model system to investigate the rather complex interaction modes between small redox molecules and a cTnI‐aptamer. Understanding these modes is an important facet in designing electrochemical aptasensors to ascertain the effectiveness of a redox indicator. In our study, docking and molecular dynamics (MD) were used to provide information on the stability, fluctuations, and interaction analysis of the complexes. Based on computational evaluations, we understand how the structure of the cTnI‐aptamer steers the MB releasing after inducing cTnI. In order to evaluate the sensing performance of the cTnI‐aptamer in the presence of MB experimentally, after covalent immobilization of the 5‐amino terminated cTnI‐aptamer at a pre‐functionalized carboxylated multi‐walled carbon nanotube (COOH‐MWCNT) glassy carbon electrode, some techniques including spectroscopy and voltammetry were employed.
Ultrasound‐Assisted Natural Deep Eutectic Solvents as Separation‐Free Extraction Media for Hydroxytyrosol from Olives
Authors: Liang Yihong , Pan Zuchen , Chen Zhengjian , Fei Yuqing , Zhang Jiliang , Yuan Jumao , Zhang Ling , Zhang Jiaheng
Published: September 2020

A range of natural deep eutectic solvents (NADESs) as separation‐free media were applied as extraction solvents in combination with ultrasound‐assisted extraction (UAE) for the extraction of hydroxytyrosol from olive fruits. Following the investigation of 7 different NADESs, a tailor‐made DES composed of malic acid and betaine (BeMa) in a 1 : 1 molar ratio was screened for its efficiency. High performance liquid chromatography (HPLC) was used to test the content of hydroxytyrosol in the extraction. Response surface methodology (RSM) combined with central composite design (CCD) was used for the experimental design. The optimum extraction efficiency was obtained using a 1 : 20 sample: solvent mass/volume ratio upon sonication for 33.65 min in an aqueous solution containing 42.13 % (w/v) DES at 43.86 °C. In addition, the zebrafish embryo toxicity test showed that the selected DES exhibited essentially no biotoxicity, while BeMa was found to increase the antibacterial ability of the target subject. Our results indicated that NADESs are promising as green and safe solvents for the extraction and analysis of active substances from natural plants.
CuII Anchored onto the Magnetic Talc: A New Magnetic Nanostructured Catalyst for the One‐Pot Gram‐Scale Synthesis of 1H‐Pyrazolo[1,2‐b]phthalazine‐5,10‐dione Derivatives
Authors: Chalaki Samaneh B. , Akhlaghinia Batool
Published: September 2020

In the present study CuII anchored onto the magnetic talc (γ‐Fe2O3/ talc /CuII NPs) was successfully synthesized and characterized by FT‐IR, XRD, TEM, FE‐SEM, EDX, VSM, and ICP‐OES techniques. Structural characterizations reveal that the γ‐Fe2O3/talc/CuII NPs are superparamagnetic in nature, structured as a composite with average diameter of about 19–31 nm. The prepared nanostructured catalyst efficiently catalyzed the preparation of 1H‐pyrazolo[1,2‐b] phthalazine‐5,10‐diones at the gram scale without the use of the toxic organic solvents. The magnetically separable and environmentally friendly nanostructured catalyst remains quite stable during reaction conditions and reused for at least five recycle runs.
Novel Bile Acid Based 1,2,3‐Triazole Receptors for Recognition of Acetate and Dihydrogen Phosphate Ions
Authors: K. Muwal Pradeep , Mishra Roli , Pandey Pramod S.
Published: September 2020

Novel bile acid‐based receptors having 1,2,3‐triazolium and 1,2,3‐triazole moieties have been synthesized using click chemistry. These receptors show high binding affinity and selectivity for acetate ion in solution. Interestingly, the 1,2,3‐triazolium receptor shows precipitation behaviour with dihydrogen phosphate ion.
Alkanolammonium Protic Ionic Liquids for Low Temperature 68Ga‐Radiolabeling of DOTA‐Functionalized Compounds
Authors: Antuganov Dmitrii , Nadporojskii Mikhail , Sysoev Dmitry , Shatik Sergey , Kondratenko Yulia
Published: September 2020

Nowadays, the radiolabeling of small biomolecules with isotope 68Ga is one of the important directions in the field of Positron‐Emission Tomography (PET). The right choice of buffer for reaction helps to achieve optimal conditions for higher yields. Earlier, we found that protic ionic liquids based on tris(2‐hydroxyethyl)ammonium and tris(hydroxymethyl)methyl ammonium salts are suitable buffers for the chelation of the 68Ga to the PSMA‐HBED‐CC (a peptide with an acyclic chelator). Herein we describe the labeling of p‐SCN‐Bn‐DOTA (DOTA=1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid) chelator and peptides (DOTA‐NOC, DOTA‐TATE, and PSMA‐617) with gallium‐68 isotope in media of alkanolammonium buffers based on tris(2‐hydroxyethyl)ammonium (TEA), tris(hydroxymethyl)methyl ammonium (TRIS) and N‐phenyl‐bis(2‐hydroxyethyl)ammonium (PDA) salts. Besides, for the first time, we present results of low‐temperature 68Ga‐complexation in the presence of organic solvents additives. An essential consequence of this study is that for the series of alkanolammonium buffers, high radiochemical conversions were achieved upon incubation of reaction media under 37 °C.
Synthesis of Extended Bipyridine‐proline Chiral Catalysts and Resulting Effects on the Asymmetric Aldol Reactions of Bulkier Aldehyde Derivatives with Cyclohexanone
Authors: Xu Guangpeng , Zhang Yajing , Sun Jihong , Bai Shiyang , Zhao Hongwu
Published: September 2020

Axially‐unfixed 2,2′‐bipyridine‐based chiral catalysts were synthesized using enantiopure amino acids as chiral sources, which were successfully used in asymmetric aldol reactions of p‐nitrobenzaldehyde with cyclohexanone, while the bulkier aldehyde derivatives (2‐naphthaldehyde, 9‐anthracenecarboxaldehyde, and 1‐pyrenecarboxaldehyde) were selected to further elucidate the catalytic properties. Particularly, the influences of the bipyridine‐proline chiral structures and the polarities of used solvents (petroleum ether, toluene, CH2Cl2, ethanol, DMF, DMSO, and water) on the catalytic performance were investigated. The results indicated that the structure of bipyridine catalysts, the molecular volume of aldehydes, and the polarity of solvents have significant eﬀects on the catalytic activities, in which, the smaller steric effects were conducive to the improvement of the yields and stereoselectivities for asymmetric aldol reaction, along with the increased polarity of used solvents and the decreased molecular volume of aldehydes. Meanwhile, the chemical identity of all compounds was confirmed by 1H‐NMR, 13C‐NMR, HRMS, and HPLC analysis.
Reduced fetal growth velocity precedes antepartum fetal death
Authors: Pacora P. , Romero R. , Jung E. , Gudicha D. W. , Hernandez‐Andrade E. , Musilova I. , Kacerovsky M. , Jaiman S. , Erez O. , Hsu C. D. , Tarca A. L.
Published: September 2020

Objectives

To determine whether decreased fetal growth velocity precedes antepartum fetal death and to evaluate whether fetal growth velocity is a better predictor of antepartum fetal death compared to a single fetal biometric measurement at the last available ultrasound scan prior to diagnosis of demise.

Methods

This was a retrospective, longitudinal study of 4285 singleton pregnancies in African‐American women who underwent at least two fetal ultrasound examinations between 14 and 32 weeks of gestation and delivered a liveborn neonate (controls; n = 4262) or experienced antepartum fetal death (cases; n = 23). Fetal death was defined as death diagnosed at ≥ 20 weeks of gestation and confirmed by ultrasound examination. Exclusion criteria included congenital anomaly, birth at < 20 weeks of gestation, multiple gestation and intrapartum fetal death. The ultrasound examination performed at the time of fetal demise was not included in the analysis. Percentiles for estimated fetal weight (EFW) and individual biometric parameters were determined according to the Hadlock and Perinatology Research Branch/Eunice Kennedy Shriver National Institute of Child Health and Human Development (PRB/NICHD) fetal growth standards. Fetal growth velocity was defined as the slope of the regression line of the measurement percentiles as a function of gestational age based on two or more measurements in each pregnancy.

Results

Cases had significantly lower growth velocities of EFW (P < 0.001) and of fetal head circumference, biparietal diameter, abdominal circumference and femur length (all P < 0.05) compared to controls, according to the PRB/NICHD and Hadlock growth standards. Fetuses with EFW growth velocity < 10th percentile of the controls had a 9.4‐fold and an 11.2‐fold increased risk of antepartum death, based on the Hadlock and customized PRB/NICHD standards, respectively. At a 10% false‐positive rate, the sensitivity of EFW growth velocity for predicting antepartum fetal death was 56.5%, compared to 26.1% for a single EFW percentile evaluation at the last available ultrasound examination, according to the customized PRB/NICHD standard.

Conclusions

Given that 74% of antepartum fetal death cases were not diagnosed as small‐for‐gestational age (EFW < 10th percentile) at the last ultrasound examination when the fetuses were alive, alternative approaches are needed to improve detection of fetuses at risk of fetal death. Longitudinal sonographic evaluation to determine growth velocity doubles the sensitivity for prediction of antepartum fetal death compared to a single EFW measurement at the last available ultrasound examination, yet the performance is still suboptimal. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.