bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Tetraoxygenated Terephthalates via a Dichloroquinone Route: Characterization of Cross‐Conjugated Liebermann Betaine Intermediates
Authors: Hintermann Lukas , Altmann Philipp J. , Naumov Panče , Suzuki Keisuke 
Published: January 2017

Cross‐conjugated quinoid betaines 4 (2,5‐bis(alkoxycarbonyl)‐3,6‐dioxo‐4‐(1‐pyridinium‐1‐yl)cyclohexa‐1,4‐dien‐1‐olates; Liebermann betaines) were synthesized from 2,5‐dichloro‐3,6‐dioxocyclohexa‐1,4‐diene‐1,4‐dicarboxylates (2) and pyridines in acetone containing H2O. Their structure was secured by NMR spectroscopy and by X‐ray diffraction analysis of 4f (alkoxy = EtO, pyridine = 4‐Me2N–C5H4N). Betaines 4 show comparatively high reactivity towards nucleophiles as a consequence of their cross‐conjugated character. Betaine 4a and hydroxy‐3,4‐methylenedioxybenzene (sesamol) condense to give a pyridinium quinolate salt 14 which has a bifurcate H‐bond from a pyridinium N+–H donor to both carbonyl (C=O) and olate (C–O−) acceptors in the solid state. Betaine 4b hydrolyzes in aqueous solution to give diethyl 2,5‐dihydroxy‐3,6‐dioxocyclohexa‐1,4‐diene‐1,4‐dicarboxylate (11) as a pyridinium salt, or as polymeric zinc(II) complex of the dianion of 11 in the presence of ZnCl2. Dihydroxyquinone 11 was analytically differentiated from its independently prepared hydroquinone form, diethyl 2,3,5,6‐tetrahydroxyterephthalate (12), by NMR analysis in solution and X‐ray crystal structure determination of both compounds.
Urinary exosomes as a novel biomarker for evaluation of α‐lipoic acid's protective effect in early diabetic nephropathy
Authors: Sun Hanxiao , Yao Weifeng , Tang Yubin , Zhuang Wenfang , Wu Dan , Huang Shan , Sheng Huiming 
Published: January 2017

BackgroundLong‐term administration of α‐lipoic acid (α‐LA) is proved to ameliorate renal impairment. Herein we assessed serum, urinary biomarkers and vascular endothelium function to evaluate its short‐period therapeutic effect and identify novel biomarkers for diabetic nephropathy (DN).MethodsSixty‐two microalbuminuria‐stage DN patients were randomly divided into two groups and received the following treatment for 8 weeks: (1) routine treatment(DM group); (2) routine treatment with 600 mg/d α‐lipoic acid intravenously (α‐LA group). Another total of 21 patients were recruited for the second‐stage study and randomly divided into two groups: normoalbuminuria (UAER <30 mg/24 h) and microalbuminuria (UAER from 30‐300 mg/24 h).ResultsWith α‐LA treatment, urinary albumin excretion rates (UAER), serum creatinine (SCr) and malonaldehyde (MDA) declined significantly, whereas plasma superoxide dismutase (SOD)activity increased and endothelium‐dependent flow mediated vasodilation (FMD) flexibility improved dramatically. Furthermore, the improvement of FMD showed positive correlation with the variation in MDA and SOD as well (r values are .516 and .435, P<.01 and P<.05, respectively). In contrast, these markers have no significant difference in the DM group with routine treatment. Notably, the CD63 expressing of exosomes in urine was found higher in the normoalbuminuria patients compared with those in microalbuminuria, parallelly only declined markedly after α‐LA administration in normoalbuminuria patients.ConclusionIn summary, we emphasize short‐term α‐LA could protect the kidney in the early DN against general oxidative stress, particularly the urinary CD63‐positive exosome could be a potential sensitive and therapeutic indicator.
The association of NLRP3 and TNFRSF1A polymorphisms with risk of ankylosing spondylitis and treatment efficacy of etanercept
Authors: Zhao Shengchun , Chen Hongwei , Wu Guolin , Zhao Chen 
Published: January 2017

BackgroundTo discover how NLRP3 and TNFRSF1A polymorphisms affect the efficacy of traditional medicine and etanercept for ankylosing spondylitis (AS) patients.MethodsSingle nucleotide polymorphism (SNP) and haplotype analyses were conducted based on determined NLRP3 and TNFRSF1A among AS patients. We subsequently analyzed the relationship between relevant clinical indexes and polymorphisms of NLRP3 and TNFRSF1A.ResultsThe 4 SNP loci on NLRP3 and 3 SNP loci on TNFRSF1A showed significant linkage disequilibrium, respectively. The T allele of NLRP3 rs4612666 and the T allele of TFRSF1A rs4149570 are both associated with AS (P<.05). The T‐A‐C‐T haplotype of NLRP3 as well as the G‐C‐C, T‐C‐C, T‐C‐T, and T‐T‐T haplotypes of TFRSF1A are associated with AS (P<.05). The morning stiffness time, BASDAI scoring, and ESR of patients receiving etanercept were significantly higher than those receiving traditional medicine. T allele of NLRP3 rs4612666 had a significantly greater negative impact on the ASAS20 improvement than C allele. Whereas the A allele of NLRP3 rs3806268 had a significantly greater positive impact on the ASAS20 improvement than G allele. There is no significant association between SNP and efficacy of traditional medicine in the treatment of AS.ConclusionNLRP3 and TFRSF1A (rs4149570) are associated with AS susceptibility. There is a significant association between NLRP3 polymorphisms and treatment of etanercept.
Clinical phenotypes and the biological parameters of Congolese patients suffering from sickle cell anemia: A first report from Central Africa
Authors: Mikobi Tite M. , Lukusa Tshilobo Prosper , Aloni Michel N. , Akilimali Pierre Z. , Mvumbi‐Lelo Georges , Mbuyi‐Muamba Jean Marie 
Published: January 2017

BackgroundThe influence of phenotype on the clinical course and laboratory features of sickle cell anemia (SCA) is rarely described in sub‐Saharan Africa.MethodsA cross‐sectional study was conducted in Kinshasa. A clinical phenotype score was built up. The following definitions were applied: asymptomatic clinical phenotype (ACP; score≤5), moderate clinical phenotype (MCP; score between 6 and 15), and severe clinical phenotype (SCP; score≥16). ANOVA test were used to compare differences among categorical variables.ResultsWe have studied 140 patients. The mean body mass index (BMI) value of three groups was lower (<25 kg/m2) than the limit defining overweight. BMI of the subjects with ACP was significantly higher than those of other phenotypes (P<.05). Sickle cell patients with ACP have a high mean steady‐state hemoglobin concentration compared to those with MCP and SCP (P<.001). A significant elevated baseline leukocyte count is associated with SCP (P<.001). Fetal Hemoglobin (HbF) was significantly higher in ACP. Significant elevation of alpha 1 and alpha 2 globulins in SCP were observed.ConclusionIn our study, fetal hemoglobin has an influence on the clinical severity and the biological parameters of SCA. The study provides data concerning the sickle cell anemia clinical and biological variability in our midst.
Elevated adiabatic T1ρ and T2ρ in articular cartilage are associated with cartilage and bone lesions in early osteoarthritis: A preliminary study
Authors: Casula Victor , Nissi Mikko J. , Podlipská Jana , Haapea Marianne , Koski Juhani M. , Saarakkala Simo , Guermazi Ali , Lammentausta Eveliina , Nieminen Miika T. 
Published: January 2017

PurposeTo evaluate adiabatic T1ρ and T2ρ of articular cartilage in symptomatic osteoarthritis (OA) patients and asymptomatic volunteers, and to determine their association with magnetic resonance imaging (MRI)‐based structural abnormalities in cartilage and bone.Materials and MethodsA total of 24 subjects (age range: 50–68 years; 12 female) were enrolled, including 12 early OA patients and 12 volunteers with normal joint function. Patients and volunteers underwent 3T MRI. T2, adiabatic T1ρ, and T2ρ relaxation times of knee articular cartilage were measured. Proton density (PD)‐ and T1‐weighted MR image series were also obtained and separately evaluated for morphological changes using the MRI OA Knee Scoring (MOAKS) system. Comparisons using the Mann–Whitney nonparametric test were performed after dividing the study participants according to physical symptoms as determined by Western Ontario and McMaster Universities (WOMAC) score or presence of cartilage lesions, bone marrow lesions, or osteophytes.ResultsElevated adiabatic T1ρ and T2ρ relaxation times of articular cartilage were associated with cartilage loss (P = 0.024–0.047), physical symptoms (0.0068–0.035), and osteophytes (0.0039–0.027). Elevated adiabatic T1ρ was also associated with bone marrow lesions (0.033).ConclusionPreliminary data suggest that elevated adiabatic T1ρ and T2ρ of cartilage are associated with morphological abnormalities of cartilage and bone, and thus may be applicable for in vivo OA research and diagnostics.Level of Evidence: 2Technical Efficacy: Stage 2J. MAGN. RESON. IMAGING 2017;46:678–689
Microstructural and functional correlates of glutamate concentration in the posterior cingulate cortex
Authors: Arrubla Jorge , Farrher Ezequiel , Strippelmann Johanna , Tse Desmond H. Y. , Grinberg Farida , Shah N. Jon , Neuner Irene 
Published: January 2017

AbstractGlutamate is the major excitatory neurotransmitter in the human brain and has a central role in both intrinsic and stimulus‐induced activity. We conducted a study in a cohort of healthy, male volunteers in which glutamate levels were measured in the posterior cingulate cortex (PCC) using 1H magnetic resonance spectroscopy at 3T. The advantages of simultaneous electroencephalography and magnetic resonance imaging (EEG‐MRI) were exploited and the subjects were measured in the same session and under the same physiological conditions. Diffusion tensor imaging (DTI), functional MRI (fMRI) and EEG were measured in order to investigate the functional and microstructural correlates of glutamate. The concentration of glutamate (institute units) was calculated and those values were tested for correlation with the metrics of resting state fMRI, DTI, and EEG electrical sources. Our results showed that the concentration of glutamate in the PCC had a significant negative correlation with the tissue mean diffusivity in the same area. The analysis of resting state networks did not show any relationship between the concentration of glutamate and the intrinsic activity of the resting state networks. The concentration of glutamate showed a positive correlation with the electrical generators of α–1 frequency and a negative correlation with the generators of α–2 and β–1 electrical generators. © 2017 Wiley Periodicals, Inc.
Long‐term analysis of the asynchronicity between temperature and precipitation maxima in the United States Great Plains
Authors: Flanagan Paul X. , Basara Jeffrey B. , Xiao Xiangming 
Published: January 2017

ABSTRACTAgriculture is a critical industry to the economy of the Great Plains (GP) region of North America and sensitive to change in weather and climate. Thus, improved knowledge of meteorological and climatological conditions during the growing season and associated variability across spatial and temporal scales is important. A distinct climate feature in the GP is the asynchronicity (AS) between the timing of temperature and precipitation maxima. This study investigated a long‐term observational data set to quantify the AS and to address the impacts of climate variability and change. Global Historical Climate Network Daily (GHCN‐Daily) data were utilized for this study; 352 GHCN‐Daily stations were identified based on specific criteria and the dates of the precipitation and temperature maxima for each year were identified at daily and weekly intervals. An asynchronous difference index (ADI) was computed by determining the difference between these dates averaged over each decade. Analysis of daily and weekly ADI revealed two physically distinct regimes of ADI (positive and negative), with comparable shifts in the timing of both the maximum of precipitation and temperature over all six states within the GP examined when comparing the two different regimes. Time series analysis of decadal average ADI yielded moderate shifts (∼5 to 10 days from linear regression analysis) in ADI in several states with increased variability occurring over much of the study region.
Comparison of spatial interpolation techniques to generate high‐resolution climate surfaces for Nigeria
Authors: Arowolo Aisha Olushola , Bhowmik Avit Kumar , Qi Wei , Deng Xiangzheng 
Published: January 2017

ABSTRACTClimate datagaps are a major challenge for understanding the impacts of climate change on ecosystems, particularly in highly climate vulnerable countries such as Nigeria. The generation of gridded climate data sets in the form of interpolated surfaces may help to fill climate datagaps and in turns enable climate change impact assessments. This article generates climate surfaces of monthly total precipitation and minimum and maximum temperatures for Nigeria at 0.001° spatial resolution by comparing two spatial interpolation techniques, i.e. kriging with external drifts and thin plate splines. Climate data from 43 meteorological stations covering the period of 1960–2012 were used to generate climate surfaces fitting the longitude, latitude, elevation and distance to coastline of the stations as independent variables. Three model error statistics, i.e. root mean square error (RMSE), Nash–Sutcliffe efficiency (NSE) and index of agreement (d), were used to evaluate and compare the performances of interpolation techniques. The second‐order and third‐order partial thin plate splines were identified as the optimal models for generating precipitation, and minimum and maximum temperatures surfaces, respectively. The best‐fit surfaces yielded an average RMSE, NSE and d of 14.98, 0.87 and 0.97 for precipitation, 0.42, 0.91 and 0.98 for minimum temperature and 0.52, 0.89 and 0.97 for maximum temperature. Our high‐resolution climate surfaces are freely available from an online repository and widely applicable for climate change analysis as well as for biological, forestry and agricultural studies in Nigeria.
Neurotological findings after electrical injury at the workplace
Authors: Wuesthoff Carolina , Ilan Ophir , Rutka John Alexander 
Published: January 2017

Objectives/HypothesisNeurotological findings secondary to electrical injuries have rarely been reported in the world literature. We attempt to characterize the neurotological findings following electrical injury and to determine the role head injury and loss of consciousness play in this population's clinical presentation.Study DesignRetrospective cohort study.MethodsA database containing 3,438 patients with work‐related injuries was scanned for individuals who sustained and survived electrical injuries at work. Detailed analysis of the frequencies of presenting features and test results was performed. A comparative analysis was made between the subsets of patients with and without loss of consciousness and/or head injury.ResultsA cohort of 42 patients was identified. All patients had multiple symptoms. Dizziness was a significant complaint in all workers with electrical injuries. Other common complaints included tinnitus and imbalance. Characterization of these symptoms is provided in detail according to statistical frequency. In this cohort, 25 workers had a concomitant head injury and 17 workers had an associated loss of consciousness. There was no statistically significant difference when clinical presentation, examination, and balance testing results were compared between the subsets.ConclusionsFrequency and characterization of symptoms following electrical injury are provided. Dizziness is the most common presenting neurotological feature. Loss of consciousness and/or associated head injury do not affect the clinical presentation in this particular population.Level of Evidence2b. Laryngoscope, 127:2126–2131, 2017
Indwelling voice prosthesis insertion after total pharyngolaryngectomy with free jejunal reconstruction
Authors: Fukushima Hirofumi , Kanazawa Takeharu , Kawabata Kazuyoshi , Mitani Hiroki , Yonekawa Hiroyuki , Sasaki Toru , Shimbashi Wataru , Seto Akira , Kamiyama Ryousuke , Misawa Kiyoshi , Asakage Takahiro 
Published: January 2017

ObjectivesTotal pharyngolaryngectomy with free jejunal reconstruction is often performed in patients with hypopharyngeal carcinoma. However, postoperative speechlessness significantly decreases patient quality of life. We investigated whether Provox® insertion could preserve speech after total pharyngolaryngectomy with free jejunal reconstruction.Study DesignRetrospective chart review.MethodsA total of 130 cases of secondary Provox® insertions after total pharyngolaryngectomy with free jejunal reconstruction were analyzed. Communication outcomes were compared using the Head and Neck Cancer Understandability of Speech Subscale. Outcomes and complications associated with insertion site (jejunal insertion vs. esophageal insertion) and adjuvant irradiation therapy were also evaluated.ResultsProvox® insertion had favorable communication outcomes in 102 cases (78.4%). Neither the insertion site nor irradiation affected the communication outcome. Complications were observed in 20 cases (15.4%). Local infection was the most common complication. Free jejunal insertion, in which the resection range was enlarged, had a lower complication rate than did esophageal insertion, and its complication rate was unaffected by previous irradiation. For all patients, the hospitalization duration and duration of speechlessness were 13.4 days and 14.6 months, respectively. Patients receiving jejunal insertions had a significantly shorter hospitalization duration than did those receiving esophageal insertions. Unlike Provox®2, Provox®Vega significantly reduced the complication rate to zero.ConclusionFor jejunal inserson of a Provox® prosthetic, a sufficient margin can be maintained during total pharyngolaryngectomy and irradiation can be performed, and satisfactory communication outcomes were observed. Provox® insertion after total pharyngolaryngectomy with free jejunal reconstruction should be considered the standard therapy for voice restoration.Level of Evidence4.
A Copolymer Scaffold Functionalized with Nanodiamond Particles Enhances Osteogenic Metabolic Activity and Bone Regeneration
Authors: Yassin Mohammed A. , Mustafa Kamal , Xing Zhe , Sun Yang , Fasmer Kristine Eldevik , Waag Thilo , Krueger Anke , Steinmüller‐Nethl Doris , Finne‐Wistrand Anna , Leknes Knut N. 
Published: January 2017

Functionalizing polymer scaffolds with nanodiamond particles (nDPs) has pronounced effect on the surface properties, such as improved wettability, an increased active area and binding sites for cellular attachment and adhesion, and increased ability to immobilize biomolecules by physical adsorption. This study aims to evaluate the effect of poly(l‐lactide‐co‐ε‐caprolactone) (poly(LLA‐co‐CL)) scaffolds, functionalized with nDPs, on bone regeneration in a rat calvarial critical size defect. Poly(LLA‐co‐CL) scaffolds functionalized with nDPs are also compared with pristine scaffolds with reference to albumin adsorption and seeding efficiency of bone marrow stromal cells (BMSCs). Compared with pristine scaffolds, the experimental scaffolds exhibit a reduction in albumin adsorption and a significant increase in the seeding efficiency of BMSCs (p = 0.027). In the calvarial defects implanted with BMSC‐seeded poly(LLA‐co‐CL)/nDPs scaffolds, live imaging at 12 weeks discloses a significant increase in osteogenic metabolic activity (p = 0.016). Microcomputed tomography, confirmed by histological data, reveals a substantial increase in bone volume (p = 0.021). The results show that compared with conventional poly(LLA‐co‐CL) scaffolds those functionalized with nDPs promote osteogenic metabolic activity and mineralization capacity. It is concluded that poly(LLA‐co‐CL) composite matrices functionalized with nDPs enhance osteoconductivity and therefore warrant further study as potential scaffolding material for bone tissue engineering.
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The Kinetics of Surface‐Initiated RAFT Polymerization of Butyl acrylate Mediated by Trithiocarbonates
Authors: Moehrke Julia , Vana Philipp 
Published: January 2017

Stationary and time‐resolved electron spin resonance spectroscopy measurements are employed to investigate the kinetics of the surface‐initiated reversible addition fragmentation chain transfer (RAFT) polymerization of n‐butyl acrylate from silica nanoparticles using both R‐ and Z‐group‐attached trithiocarbonates as RAFT agents. The obtained kinetic parameters reveal that the addition rate coefficient in the main equilibrium of RAFT graft polymerizations is significantly smaller than the one for comparable RAFT polymerizations in solution phase, as translational diffusion of surface‐attached molecules is limited. In comparison to the R‐group approach, the equilibrium constants of the Z‐group approach are about one to two orders of magnitude smaller due to a stronger shielding of the RAFT moieties.
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Nitrogen‐Doped Nanocarbons Derived from Tetrazine Cross‐Linked Poly(4‐cyanostyrene)‐Silica Hybrids
Authors: Lamson Melissa , Chen Luyi , Zhong Mingjiang , Wu Dingcai , Matyjaszewski Krzysztof 
Published: January 2017

Nanoporous carbon materials containing heteroatoms are important for various applications. Novel carbon precursors containing cyano groups are grafted from silica particles by surface‐initiated atom transfer radical polymerization of 4‐cyanostyrene. The poly(4‐cyanostyrene) grafted silica particles are cross‐linked via the Pinner reaction to form tetrazine cross‐linking units. The cross‐linked nanoparticles exhibit intra‐ and interparticle cross‐linking, as confirmed by dynamic light scattering and scanning electron microscope analysis. Subsequent carbonization and silica etching yield a 3D‐interconnected network of nitrogen‐doped nanocarbons with surface areas exceeding 750 m2 g−1.
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Direct Synthesis of Fractal Polymer Dispersions by Miniemulsion Polymerization
Authors: López Ana B. , de la Cal José C. , Asua José M. 
Published: January 2017

Fractal colloids, which find applications in the preparation of advanced materials, are currently synthesized by means of a multistep procedure that yields a low solids content dispersion. This is not well suited for certain applications such as superhydrophobic coatings. In this work, a one‐step method for the synthesis of higher solids content waterborne fractal polymer dispersions is presented and it is shown that the surfaces obtained from the fractal dispersions are superhydrophobic (contact angle, θ > 150°) which is beyond the current waterborne coating technology (θ = 130°–137°). This opens the possibility for the large‐scale production of waterborne superhydrophobic coatings.
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Doubly Dynamic Self‐Healing Materials Based on Oxime Click Chemistry and Boronic Acids
Authors: Collins Joe , Nadgorny Milena , Xiao Zeyun , Connal Luke A. 
Published: January 2017

The dynamic covalent characteristics of oxime and boronate ester bonds have been explored. A small excess of a competing aldehyde under acidic conditions resulted in oxime polymer degradation from high molecular weights (30 kDa) to low molecular weight oligomers (2.2 kDa). The dynamic nature of oxime bonds imparts oxime cross‐linked hydrogels with self‐healing properties and the incorporation of phenyl boronic acid groups into the hydrogel network provides a platform for hydrogel functionalization. The addition of a polyphenol (tannic acid) proves a facile means to incorporate a second, dynamic covalent cross‐linking network through boronate ester formation which, owing to the increase in the degree of cross‐linking, is found to be nearly double the hydrogel strength (storage modulus increased from 4.6 to 8.5 kPa). Finally, the tannic acid cross‐linking network is selectively degraded returning the hydrogel storage modulus to its initial value and providing a means for the synthesis of materials with tunable mechanical properties.
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