bluuebunny/crossref_metadata_2025_split huggingface dataset:
Divergent Synthesis of Oxa‐Cyclic Nitrones through Gold(I)‐Catalyzed 1,3‐Azaprotio Transfer of Propargylic α‐Ketocarboxylate Oximes: Experimental and DFT Studies
Authors: Wang Chunhong , Cui Qi , Zhang Zhixin , Yao Zhu‐Jun , Wang Shaozhong , Yu Zhi‐Xiang 
Published: May 2019

Abstract1,3‐Azaprotio transfer of propargylic α‐ketocarboxylate oximes, a new type of alkynyl oximes featuring an ester tether, has been explored by taking advantage of gold catalysis. The incorporation of an oxygen atom to the chain of alkynyl oximes led to the formation of two different oxa‐cyclic nitrones. It was found that internal alkynyl oximes with an E‐configuration deliver five‐membered nitrones, whereas terminal alkynyl oximes with an E‐configuration afford six‐membered nitrones. DFT calculations on four possible pathways supported a stepwise formation of C−N and C−H bonds, in which a 1,3‐acyloxy‐migration competes with the 1,3‐azaprotio‐transfer, especially in the case of internal alkynyl oximes. The relative nucleophilic properties of oxygen in the carbonyl group and the nitrogen in the oxime, the electronic effects of alkynes, and the influence of the ring system have been investigated computationally.
CuII and AuIII Complexes with Glycoconjugated Dithiocarbamato Ligands for Potential Applications in Targeted Chemotherapy
Authors: Pettenuzzo Nicolò , Brustolin Leonardo , Coltri Elisa , Gambalunga Alberto , Chiara Federica , Trevisan Andrea , Biondi Barbara , Nardon Chiara , Fregona Dolores 
Published: May 2019

AbstractThis work is focused on the synthesis, characterization, and preliminary biological evaluation of bio‐conjugated AuIII and CuII complexes with the aim of overcoming the well‐known side effects of chemotherapy by improving the selective accumulation of an anticancer metal payload in malignant cells. For this purpose, carbohydrates were chosen as targeting agents, exploiting the Warburg effect that accounts for the overexpression of glucose‐transporter proteins (in particular GLUTs) in the phospholipid bilayer of most neoplastic cells. We linked the dithiocarbamato moiety to the C1 position of three different monosaccharides: d‐glucose, d‐galactose, and d‐mannose. Altogether, six complexes with a 1:2 metal‐to‐ligand stoichiometry were synthesized and in vitro tested as anticancer agents. One of them showed high cytotoxic activity toward the HCT116 colorectal human carcinoma cell line, paving the way to future in vivo studies aimed at evaluating the role of carbohydrates in the selective delivery of whole molecules into cancerous cells.
Pathologic staging changes in oral cavity squamous cell carcinoma: Stage migration and implications for adjuvant treatment
Authors: Lee Nicholas C. J. , Eskander Antoine , Park Henry S. , Mehra Saral , Burtness Barbara A. , Husain Zain 
Published: May 2019

BackgroundThe eighth edition of the AJCC Cancer Staging Manual (AJCC 8) incorporates depth of invasion (DOI) into the pathologic tumor (pT) classification and pathologic extranodal extension (pENE) into the pathologic nodal (pN) classification for oral cavity squamous cell carcinoma (OCSCC). This study evaluated the incidence and prognostic importance of stage migration as a result of these changes in the AJCC 8 staging system.MethodsFrom the National Cancer Database, cohorts were identified from patients with OCSCC undergoing definitive surgery between 2004 and 2013 for pT (n = 7184), pN (n = 13,627), and pathologic stage (pStage) analysis (n = 5580).ResultsDOI and pENE were prognostic in all groups except for pN3 according to the seventh edition of the AJCC Cancer Staging Manual (AJCC 7). Upstaging was seen in 12.4% of patients for the pT classification, in 13.3% for the pN classification, and in 24.8% for the overall pStage grouping. Notably, upstaging led to similar or improved 5‐year overall survival (OS) for every AJCC 8 pT/N classification except pStage IVB. Patients with AJCC 7 pT1 tumors that were upstaged to AJCC 8 pT3 tumors had improved OS in comparison with the remainder of the pT3 group (71.7% vs 43.7%; P < .0001). A multivariable analysis of upstaged pT3N0 patients demonstrated a reduced risk of death with the receipt of postoperative radiotherapy (PORT; hazard ratio, 0.56; 95% confidence interval, 0.33‐0.95; P = .03).ConclusionsUpstaging is common in AJCC 8, and patients with upstaged tumors demonstrate improved survival; these factors should be kept in mind when one is interpreting data with the new staging system. PORT may reduce deaths among newly upstaged pT3N0 patients, and further study is needed in this area.
Patient‐reported and clinician‐reported chemotherapy‐induced peripheral neuropathy in patients with early breast cancer: Current clinical practice
Authors: Nyrop Kirsten A. , Deal Allison M. , Reeder‐Hayes Kathryn E. , Shachar Shlomit S. , Reeve Bryce B. , Basch Ethan , Choi Seul Ki , Lee Jordan T. , Wood William A. , Anders Carey K. , Carey Lisa A. , Dees Elizabeth C. , Jolly Trevor A. , Kimmick Gretchen G. , Karuturi Meghan S. , Reinbolt Raquel E. , Speca JoEllen C. , Muss Hyman B. 
Published: May 2019

BackgroundIn the current study, the authors investigated the incidence of moderate to severe chemotherapy‐induced peripheral neuropathy (CIPN) for chemotherapy regimens commonly used in current clinical practice for the treatment of patients with early breast cancer. Patient‐reported and clinician‐assessed CIPN severity scores were compared, and risk factors for CIPN severity were identified.MethodsPatients completed a Patient‐Reported Symptom Monitoring form and oncologists completed a Common Terminology Criteria for Adverse Events form. CIPN reports were collected prospectively during regularly scheduled infusion visits throughout the duration of chemotherapy.ResultsThe sample included 184 women with a mean age of 55 years; approximately 73% were white. The 4 chemotherapy regimens used were doxorubicin and cyclophosphamide plus paclitaxel (60 patients); docetaxel and cyclophosphamide (50 patients); docetaxel, carboplatin, and anti–human epidermal growth factor receptor 2 (HER2) (24 patients); and doxorubicin and cyclophosphamide plus paclitaxel and carboplatin (18 patients). All patients treated with doxorubicin and cyclophosphamide plus paclitaxel and doxorubicin and cyclophosphamide plus paclitaxel and carboplatin received paclitaxel; all patients treated with docetaxel and cyclophosphamide and docetaxel, carboplatin, and anti‐HER2 received docetaxel. The chemotherapy dose was reduced in 52 patients (28%); in 15 patients (29%), this reduction was due to CIPN. Chemotherapy was discontinued in 26 patients (14%), 8 because of CIPN. Agreement between patient‐reported and clinician‐assessed CIPN severity scores was minimal (weighted Cohen kappa, P = .34). Patient‐reported moderate to severe CIPN was higher for paclitaxel (50%) compared with docetaxel (17.7%) (P < .001). Pretreatment arthritis and/or rheumatism (relative risk [RR], 1.58; 95% CI, 1.06‐2.35 [P = .023]) and regimens containing paclitaxel (RR, 2.88; 95% CI, 1.72‐4.83 [P < .0001]) were associated with higher CIPN severity. Being married (RR, 0.57; 95% CI, 0.37‐0.887 [P = .01]) was found to be associated with lower CIPN severity.ConclusionsThe discrepancy between patient‐reported and clinician‐assessed CIPN underscores the need for both patient and clinician perspectives regarding this common, dose‐limiting, and potentially disabling side effect of chemotherapy.
Chirality and Excited State Proton Transfer: From Sensing to Asymmetric Synthesis
Authors: Posey Victoria , Hanson Kenneth 
Published: May 2019

AbstractExcited state proton transfer (ESPT) is a unique photochemical process where the electron density shift of a molecule in the excited state dramatically decreases the pKa value of a proton donor site. A majority of ESPT research to date has focused on achiral molecules but there is growing interest in understanding/harnessing ESPT to/from chiral molecules. This review summarizes and critically examines the literature to date describing the role of ESPT in enantioselective fluorescence sensing, asymmetric synthetic organic chemistry, and photoisomerization of chiral molecules. Our goal is to show that despite ESPT of chiral molecules being a relatively new pursuit, there has been significant progress and even greater potential for ESPT in these and other applications yet to be realized.
Condensation of laser‐produced gold plasma during expansion and cooling in a water environment
Authors: Petrov Yu.V. , Inogamov N.A. , Zhakhovsky V.V. , Khokhlov V.A. 
Published: May 2019

Physical processes involved in laser ablation in liquid (LAL) are studied using a gold target irradiated through transparent water. During and after irradiation, the heated material from the surface of a target produces a plume that expands into liquid‐forming nanoparticles (NPs). The LAL method of NP production is ecologically much cleaner than others. A better understanding of the processes associated with complicated hydrodynamic phenomena leading to LAL is important for controlled manufacturing. We consider laser pulses with different durations τL covering fifth orders of magnitudes ranging from 0.1 ps to 0.5 ns and large absorbed fluences Fabs near optical breakdown of liquid. It is shown that the trajectory of the contact boundary with liquid at the middle and late stages after passing the maximum intensity of the longest pulse is rather similar for very different pulse durations if energies Fabs are comparable. We trace how hot (in a few eV range) dense gold plasma expands, cools down, intersects a saturation curve, and condenses into NPs appearing first inside the water‐gold diffusively mixed intermediate layer where gold vapour has the lowest temperature. Later, the pressure around the gold‐water contact drops down below the critical pressure for water. As a result, the nanoparticles find themselves in gaseous water bubble where density of water gradually decreases to 10−4 − 10−5  g/cm3 at maximum bubble expansion.
Understory plant composition and nitrogen transformations resistant to changes in seasonal precipitation
Authors: Ploughe Laura W. , Dukes Jeffrey S. 
Published: May 2019

AbstractClimate change has increased global mean surface temperatures and altered hydrological processes, and projections suggest that these changes will accelerate. As seasonal precipitation patterns change, so will the soil resources available for plants. In the midwestern United States, winter temperatures and precipitation are expected to increase, while snowfall is expected to be reduced. Reduced snowpack could lead to greater frost damage and alter the timing and amount of plant available resources at the start of the growing season. In the summer, precipitation is expected to decrease, and variability is expected to increase, creating longer and more frequent dry periods. In temperate forests, herbaceous understory plants and woody plants in early developmental stages are expected to be highly sensitive to changes in abiotic conditions. Here, we study how seasonal changes in precipitation affect the timing and availability of resources in a temperate deciduous forest. Further, we examine how changes in abiotic conditions influence understory composition and woody plant recruitment. We established a fully factorial experiment that manipulated winter snowfall and summer precipitation to create wet, dry, and control (ambient) conditions in a temperate deciduous forest near West Lafayette, Indiana, USA. We found that large changes in winter and summer precipitation appeared to affect forest processes independently of one another, and changes in seasonal precipitation altered understory composition minimally and had little to no effect on mineralization rates. The recruitment of woody plant species may be more sensitive to altered precipitation, as snow removal lowered germination rates and wet summer conditions lowered relative growth of a woody plant species, Lindera benzoin. In general, though, ecological processes in this forest understory were relatively resistant to change, at least in the short timeframe of this experiment.
TCR‐induced alteration of primary MHC peptide anchor residue
Authors: Madura Florian , Rizkallah Pierre J. , Legut Mateusz , Holland Christopher J. , Fuller Anna , Bulek Anna , Schauenburg Andrea J. , Trimby Andrew , Hopkins Jade R. , Wells Stephen A. , Godkin Andrew , Miles John J. , Sami Malkit , Li Yi , Liddy Nathaniel , Jakobsen Bent K. , Loveridge E. Joel , Cole David K. , Sewell Andrew K. 
Published: May 2019

AbstractThe HLA‐A*02:01‐restricted decapeptide EAAGIGILTV, derived from melanoma antigen recognized by T‐cells‐1 (MART‐1) protein, represents one of the best‐studied tumor associated T‐cell epitopes, but clinical results targeting this peptide have been disappointing. This limitation may reflect the dominance of the nonapeptide, AAGIGILTV, at the melanoma cell surface. The decapeptide and nonapeptide are presented in distinct conformations by HLA‐A*02:01 and TCRs from clinically relevant T‐cell clones recognize the nonapeptide poorly. Here, we studied the MEL5 TCR that potently recognizes the nonapeptide. The structure of the MEL5‐HLA‐A*02:01‐AAGIGILTV complex revealed an induced fit mechanism of antigen recognition involving altered peptide–MHC anchoring. This “flexing” at the TCR–peptide–MHC interface to accommodate the peptide antigen explains previously observed incongruences in this well‐studied system and has important implications for future therapeutic approaches. Finally, this study expands upon the mechanisms by which molecular plasticity can influence antigen recognition by T cells.
Synthesis of MoO3/polypyrrole nanocomposite and its adsorptive properties toward cadmium(II) and nile blue from aqueous solution: Equilibrium isotherm and kinetics modeling
Authors: Siddiqui Mohammad Fuzail , Khan Equbal A. , Alam Khan Tabrez 
Published: May 2019

AbstractMolybdenum trioxide/polypyrrole (MoO3/Ppy) nanocomposite was prepared via oxidative polymerization of pyrrole monomer with MoO3 nanoparticles. The adsorption of Cd+2 and nile blue (NB) onto the nanocomposite was investigated in terms of various process parameters. The characterization of MoO3/Ppy nanocomposite was carried out by Fourier transform‐infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, and energy dispersive X‐ray spectroscopy. Higher R2 (0.992–0.997 for Cd+2 and 0.997–0.998 for NB) and lower standard error of estimation values (1.04–1.82 for Cd+2 and 0.87–1.07 for NB) for Freundlich isotherm highlighted the multilayer adsorption onto heterogeneous nanocomposite surface. The higher Qm values at 323 K for Cd+2 (181 mg/g) and NB (189 mg/g) compared to many reported adsorbents proved the adsorptive superiority of MoO3/Ppy. The energy of adsorption (E) values from Dubinin–Radushkevich model was 1.26–1.38 and 1.36–1.44 kJ/mol for Cd+2 and NB, respectively, suggesting physical adsorption. Pseudo‐second order kinetic model governed the adsorption of Cd+2 and NB with intraparticle and liquid film diffusion controlling the mechanism. The negative ΔG values (8.4–9.4 kJ/mol) and positive ΔH values (2.5–6.1 kJ/mol) implied spontaneous and endothermic adsorption process. The positive ΔS values (0.036–0.048 kJ/mol/K) indicated increased randomness at MoO3/Ppy‐Cd+2 or NB interface. The MoO3/Ppy nanocomposite proved to be suitable and efficient adsorbent for sequestering of Cd+2 and NB from aqueous solution.
Influence of prior pH and thermal stresses on thermal tolerance of foodborne pathogens
Authors: Kim Chyer , Bushlaibi Mariam , Alrefaei Rana , Ndegwa Eunice , Kaseloo Paul , Wynn Crystal 
Published: May 2019

AbstractImproper food processing is one of the major causes of foodborne illness. Accurate prediction of the thermal destruction rate of foodborne pathogens is therefore vital to ensure proper processing and food safety. When bacteria are subjected to pH and thermal stresses during growth, sublethal stresses can occur that may lead to differences in their subsequent tolerance to thermal treatment. As a preliminary study to test this concept, the current study evaluated the effect of prior pH and thermal stresses on thermal tolerance of Salmonella and Staphylococcus using a tryptic soy broth supplemented with yeast extract. Bacteria incubated at three pH values (6.0, 7.4, and 9.0) and four temperatures (15, 25, 35, and 45°C) for 24 hr were subjected to thermal treatments at 55, 60, and 65°C. At the end of each treatment time, bacterial suspensions were surface‐plated on standard method agar for quantification of bacterial survival and further calculation of the thermal death decimal reduction time (D‐value) and thermal destruction temperature (z‐value). The effect of pH stress alone during the incubation on the thermal tolerance of both bacteria was generally insignificant. An increasing pattern of D‐value was observed with the increment of thermal stress (incubation temperature). The bacteria incubated at 35°C required the highest z‐value to reduce the 90% in D‐values. Staphylococcus mostly displayed higher tolerance to thermal treatment than Salmonella. Although further research is needed to validate the current findings on food matrices, findings in this study clearly affirm that adaptation of bacteria to certain stresses may reduce the effectiveness of preservation procedures applied during later stage of food processing and storage.
Evaluation of nutritional value ofAsystasia mysorensisandSesamum angustifoliaand their potential contribution to human health
Authors: Maina Ernest G. , Madivoli Edwin S. , Ouma Josephine A. , Ogilo Joel K. , Kenya Jackson M. 
Published: May 2019

AbstractWild indigenous vegetables make considerable contributions to food baskets among subsistence farmers in sub‐Saharan Africa. The aim of this study was to evaluate the proximate analysis, mineral composition, vitamin C content, β‐carotene content, and GC‐MS profile of crude methanolic extracts ofAsystasia mysorensisandSesamum angustifolia. Crude extracts obtained through sequential extraction using ethyl acetate and methanol were screened for the presence of secondary metabolites. Functional groups present were determined with a Shimadzu FT‐IR spectrophotometer, while β‐carotene content and ascorbic acid content were evaluated using a Shimadzu HPLC and Shimadzu UV‐VIS spectrophotometer, respectively. Secondary metabolites present in the extracts were determined qualitatively using a Shimadzu GC‐MS system equipped with a NIST spectral database. From the results obtained, the two plants could supply the recommended daily requirement for micronutrient and vitamin C content needed for a healthy diet. The total phenolic and flavonoid contents inS. amgustifoliawere higher as compared toA. myorensis;hence, their consumption is highly beneficial as some compounds identified in the GC‐MS profile have been reported to have medicinal properties. The findings on the mineral and chemical composition, GC‐MS profile ofA. mysorensisandS. angustifoliaindicate that their consumption may provide the recommended nutritional requirements needed for a healthy diet.
Evaluation of the 3D fractal dimension as a marker of structural brain complexity in multiple‐acquisition MRI
Authors: Krohn Stephan , Froeling Martijn , Leemans Alexander , Ostwald Dirk , Villoslada Pablo , Finke Carsten , Esteban Francisco J. 
Published: May 2019

AbstractFractal analysis represents a promising new approach to structural neuroimaging data, yet systematic evaluation of the fractal dimension (FD) as a marker of structural brain complexity is scarce. Here we present in‐depth methodological assessment of FD estimation in structural brain MRI. On the computational side, we show that spatial scale optimization can significantly improve FD estimation accuracy, as suggested by simulation studies with known FD values. For empirical evaluation, we analyzed two recent open‐access neuroimaging data sets (MASSIVE and Midnight Scan Club), stratified by fundamental image characteristics including registration, sequence weighting, spatial resolution, segmentation procedures, tissue type, and image complexity. Deviation analyses showed high repeated‐acquisition stability of the FD estimates across both data sets, with differential deviation susceptibility according to image characteristics. While less frequently studied in the literature, FD estimation in T2‐weighted images yielded robust outcomes. Importantly, we observed a significant impact of image registration on absolute FD estimates. Applying different registration schemes, we found that unbalanced registration induced (a) repeated‐measurement deviation clusters around the registration target, (b) strong bidirectional correlations among image analysis groups, and (c) spurious associations between the FD and an index of structural similarity, and these effects were strongly attenuated by reregistration in both data sets. Indeed, differences in FD between scans did not simply track differences in structure per se, suggesting that structural complexity and structural similarity represent distinct aspects of structural brain MRI. In conclusion, scale optimization can improve FD estimation accuracy, and empirical FD estimates are reliable yet sensitive to image characteristics.
Widespread and lateralized social brain activity for processing dynamic facial expressions
Authors: Sato Wataru , Kochiyama Takanori , Uono Shota , Sawada Reiko , Kubota Yasutaka , Yoshimura Sayaka , Toichi Motomi 
Published: May 2019

AbstractDynamic facial expressions of emotions constitute natural and powerful means of social communication in daily life. A number of previous neuroimaging studies have explored the neural mechanisms underlying the processing of dynamic facial expressions, and indicated the activation of certain social brain regions (e.g., the amygdala) during such tasks. However, the activated brain regions were inconsistent across studies, and their laterality was rarely evaluated. To investigate these issues, we measured brain activity using functional magnetic resonance imaging in a relatively large sample (n = 51) during the observation of dynamic facial expressions of anger and happiness and their corresponding dynamic mosaic images. The observation of dynamic facial expressions, compared with dynamic mosaics, elicited stronger activity in the bilateral posterior cortices, including the inferior occipital gyri, fusiform gyri, and superior temporal sulci. The dynamic facial expressions also activated bilateral limbic regions, including the amygdalae and ventromedial prefrontal cortices, more strongly versus mosaics. In the same manner, activation was found in the right inferior frontal gyrus (IFG) and left cerebellum. Laterality analyses comparing original and flipped images revealed right hemispheric dominance in the superior temporal sulcus and IFG and left hemispheric dominance in the cerebellum. These results indicated that the neural mechanisms underlying processing of dynamic facial expressions include widespread social brain regions associated with perceptual, emotional, and motor functions, and include a clearly lateralized (right cortical and left cerebellar) network like that involved in language processing.