bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermal degradation and ageing behavior of microcomposites of natural rubber, carboxylated styrene butadiene rubber latices, and their blends
Authors: Stephen Ranimol , Siddique A. M. , Singh Fouran , Kailas Lekshmi , Jose Seno , Joseph Kuruvilla , Thomas Sabu 
Published: March 2007

AbstractThe effect of microfillers on the thermal stability of natural rubber (NR), carboxylated styrene butadiene rubber (XSBR) latices, and their 70/30 NR/XSBR blend were studied using thermogravimetric method. Microcomposites of XSBR and their blend were found to be thermally more stable than unfilled samples. The activation energy needed for the degradation of polymer chain was calculated from Coats‐Redfern plot. Activation energy needed for the thermal degradation of filled samples was higher than unfilled system. It indicated the improved thermal stability of the filled samples. The ageing resistance of the micro‐filled samples was evaluated from the mechanical properties of aged samples. The thermal ageing was carried out by keeping the samples in hot air oven for 7 days at 70°C. The mechanical properties such as tensile strength, modulus at 300% elongation, and strain at break were computed. As compared to unfilled samples, micron‐sized fillers reinforced systems exhibited higher ageing resistance. Finally, an investigation was made on the influence of ion‐beam irradiation on microcomposites of NR, XSBR latices, and their 70/30 blend systems using 28Si8+ performed at 100 MeV. The surface changes of the samples after irradiation were analyzed using X‐ray photoelectron spectroscopy. The results of XPS measurements revealed that the host elements were redistributed without any change in binding energies of C1s, O1s, and Si2p. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Percutaneous closure of an aortic paravalvular leak via the transradial approach
Authors: Hildick‐Smith D. , Behan M.W.H. , De Giovanni J. 
Published: March 2007

AbstractPercutaneous closure of aortic and mitral paraprosthetic leaks using the Amplatzer Occluders (muscular ventricular septal defect occluder) is now a well recognized procedure although as “off label” use. Aortic paravalvular leak closure is usually carried out via transfemoral puncture, but problems with this approach include the need to stop warfarin and the inadequate length of standard delivery sheaths. We report the first case of percutaneous aortic paravalvular leak closure through via the transradial route. © 2007 Wiley‐Liss, Inc.
Allele Specific C‐Bulge Probes with One Unique Fluorescent Molecule Discriminate the Single Nucleotide Polymorphism in DNA
Authors: Takei Fumie , Suda Hitoshi , Hagihara Masaki , Zhang Jinhua , Kobori Akio , Nakatani Kazuhiko 
Published: March 2007

AbstractA combination of an allele specific C‐bulge probe and the fluorescent molecule N,N′‐bis(3‐aminopropyl)‐2,7‐diamino‐1,8‐naphthyridine (DANP) that binds specifically to the C‐bulge provides a method for single nucleotide polymorphism (SNP) typing with only one fluorescent molecule without covalent modification of the DNA probe. The allele specific C‐bulge probe contains one additional cytosine and produces a C‐bulge directly flanking the SNP site upon hybridization to the target DNA. The C‐bulge is a scaffold to recruit and retain DANP directly neighboring the SNP site. The DANP fluorescent probe was selectively modulated by the flanking matched and mismatched base pairs. The mutation type could be discriminated by the modulated fluorescent intensity with respect to the allele specific C‐bulge probes used for the assay.
Mutual kinetic separation of isotopomers of pentafluorophenyl 2‐phenyl propionate using quasi‐enantiomeric oxazolidinones
Authors: Chavda Sameer , Coumbarides Gregory S. , Dingjan Marco , Eames Jason , Flinn Anthony , Northen Julian 
Published: March 2007

AbstractMutual separation of an equimolar mixture of quasi‐enantiomeric [D,13C]‐labeled isotopomers of pentafluorophenyl 2‐phenylpropionate can be achieved efficiently by use of two quasi‐enantiomeric Evans' oxazolidinones. The levels of stereocontrol were high, leading to products with predictable configurations. Chirality, 2007. © 2007 Wiley‐Liss, Inc.
Chiral crystallization of glutamic acid on self assembled films of cysteine
Authors: Dressler David H. , Mastai Yitzhak 
Published: March 2007

AbstractIn this article, we describe the preparation and use of chiral surfaces derived from enantiomerically pure crystals of amino acids. For this purpose, we chose to employ a self‐assembly process to grow nanoscale chiral films of (+)‐l or (−)‐d cysteine, onto gold surfaces. We utilized those chiral films as resolving auxiliaries in the crystallization of enantiomers from solutions. To demonstrate the chiral discriminating ability of the chiral surfaces in crystallization processes, we investigated the crystallization of rac‐glutamic acid onto the chiral films. Our study demonstrates the potential application of chiral films to control chirality throughout crystallization, where one enantiomer crystallizes on the chiral surfaces with relatively high enantiomeric excess. In addition, crystallization of pure glutamic acid enantiomers, and its racemic compound on to chiral films resulted in crystal morphology modification with preferred crystal orientation, which assists in the interpretation of the ability of our chiral surfaces to function as chiral selectors. Chirality, 2007. © 2007 Wiley‐Liss, Inc.
Microtubules' interaction with cell cortex is required for their radial organization, but not for centrosome positioning
Authors: Brodsky I. B. , Burakov A. V. , Nadezhdina E. S. 
Published: March 2007

AbstractMicrotubules in interphase mammalian cells usually form a radial array with minus‐ends concentrated in the central region and plus‐ends placed at the periphery. This is accepted as correct, that two factors determinate the radial organization of microtubules ‐ the centrosome, which nucleate and anchor the microtubules minus‐ends, and the interaction of microtubules with cortical dynein, which positions centrosome in the cell center. However, it looks as if there are additional factors, affecting the radial structure of microtubule system. We show here that in aged Vero cytoplasts (17 h after enucleation) microtubule system lost radial organization and became chaotic. To clear up the reasons of that, we studied centrosome activity, its position in the cytoplasts and microtubule dynamics. We found that centrosome in aged cytoplasts was still active and placed in the central region of the cytoplasm, while after total disruption of the microtubules it was displaced from the center. Microtubules in aged cytoplasts were not stabilized, but they lost their ability to stop to grow near cell cortex and continued to grow reaching it. Aged cytoplast lamellae was partially depleted with dynactin though Golgi remained compact indicating dynein activity. We conclude that microtubule stoppage at cell cortex is mediated by some (protein) factors, and these factors influence radial structure of microtubule system. It seems that the key role in centrosome positioning is played by dynein complexes anchored everywhere in the cytoplasm rather than anchored in cell cortex. Cell Motil. Cytoskeleton 2007. © 2007 Wiley‐Liss, Inc.
Centralization of care for patients with advanced‐stage ovarian cancer
Authors: Bristow Robert E. , Santillan Antonio , Diaz‐Montes Teresa P. , Gardner Ginger J. , Giuntoli Robert L. , Meisner Benjamin C. , Frick Kevin D. , Armstrong Deborah K. 
Published: March 2007

AbstractBACKGROUND.The objective of this study was to evaluate the cost‐effectiveness of centralized referral of patients with advanced‐stage epithelial ovarian cancer who underwent primary cytoreductive surgery and adjuvant chemotherapy.METHODS.A decision‐analysis model was used to compare 2 referral strategies for patients with advanced‐stage ovarian cancer: 1) referral to an expert center, with a rate of optimal primary cytoreduction of 75% and utilization of combined intraperitoneal and intravenous adjuvant chemotherapy, and 2) referral to a less experienced center, with a rate of optimal primary cytoreduction of 25% and adjuvant treatment that consisted predominantly of intravenous chemotherapy alone. The cost‐effectiveness of each strategy was evaluated from the perspective of society.RESULTS.A cost‐effectiveness analysis revealed that the strategy of expert center referral had an overall cost per patient of $50,652 and had an effectiveness of 5.12 quality‐adjusted life years (QALYs). The strategy of referral to a less experienced center carried an overall cost of $39,957 and had an effectiveness of 2.33 QALYs. The expert center strategy was associated with an additional 2.78 QALYs at an incremental cost of $10,695 but was more cost‐effective, with a cost‐effective ratio of $9893 per QALY compared with $17,149 per QALY for the less experienced center referral strategy. Sensitivity analyses and a Monte Carlo simulation confirmed the robustness of the model.CONCLUSIONS.According to results from the decision‐analysis model, centralized referral of patients with ovarian cancer to an expert center was a cost‐effective healthcare strategy and represents a paradigm for quality cancer care, delivering superior patient outcomes at an economically affordable cost. Increased efforts to align current patterns of care with a universal strategy of centralized expert referral are warranted. Cancer 2007. © 2007 American Cancer Society.
Assessment of prognosis with the total illness burden index for prostate cancer
Authors: Litwin Mark S. , Greenfield Sheldon , Elkin Eric P. , Lubeck Deborah P. , Broering Jeanette M. , Kaplan Sherrie H. 
Published: March 2007

AbstractBACKGROUND.Among the most pressing challenges that face physicians who care for men with prostate cancer is evaluating the patient's potential for benefiting from treatment. Because prostate cancer often follows an indolent course, the presence and severity of comorbidities may influence the decision to treat the patient aggressively. The authors adapted the Total Illness Burden Index (TIBI) for use in decision‐making among men with prostate cancer at the time of the visit.METHODS.An observational study was performed of 2894 participants in the Cancer of the Prostate Strategic Urologic Research Endeavor, a national disease registry of men with prostate cancer, to examine how well the adapted TIBI for prostate cancer (TIBI‐CaP) predicted mortality over the subsequent 3.5 years and health‐related quality of life over the subsequent 6 months.RESULTS.The men who had the highest global TIBI‐CaP scores were 13 times more likely to die of causes other than prostate cancer over a 3.5‐year period than the men who had the lowest scores (hazard ratio, 13.1, 95% confidence interval, 6.3–27.4) after controlling for age, education, income, and race/ethnicity. Patients who had the highest TIBI‐CaP scores had 44% mortality compared with 4.9% mortality for patients who had the lowest scores. Demographic variables explained 16% of the variance in future physical function; TIBI‐CaP scores explained an additional 19% of the variance.CONCLUSIONS.The TIBI‐CaP, a patient‐reported measure of comorbidity, identified patients at high risk for nonprostate cancer mortality. It predicted both mortality and future quality of life. The TIBI‐CaP may aid physicians and patients in making appropriate treatment decisions. Cancer 2007. © 2007 American Cancer Society.
Glycemic control is related to the severity of impaired thermal sensations in type 2 diabetes
Authors: Chao Chi‐Chao , Hsieh Song‐Chou , Yang Wei‐Shiung , Lin Yea‐Hui , Lin Whei‐Min , Tai Tong‐Yuan , Hsieh Sung‐Tsang 
Published: March 2007

AbstractBackgroundSmall‐fibre sensory neuropathy of diabetes presenting as impaired thermal sensations is associated with ominous consequences, such as foot ulcer and amputation, but there is a lack of systematic studies on its occurrence in large cohorts. We investigated (1) the impact of glycemic control on thermal thresholds, (2) the frequencies and patterns of sensory deficits, and (3) the contribution of sensory nerve abnormalities to neuropathic symptoms.MethodsQuantitative sensory testing and nerve conduction studies were performed to measure warm and cold thresholds of extremities, and amplitudes of nerve action potentials on 498 type 2 diabetic patients and 434 control subjects with similar age and gender distributions, enrolled during the same period.ResultsThe diabetic patients had higher thermal thresholds than control subjects (p < 0.0001). Thermal thresholds of the lower and upper extremities were linearly correlated with HbA1C on multiple linear regression analysis (p < 0.01). By the multivariate logistic regression analysis, HbA1C and age were the most important risk factors independently associated with elevated thermal thresholds (p < 0.01). Elevated warm threshold in the big toe was the most frequent abnormality (60.2%) compared to abnormal cold threshold in the big toe (39.6%) and abnormal sural nerves on nerve conduction studies (12.9%). Elevated thermal thresholds were risk factors for neuropathic symptoms independent of HbA1C.ConclusionSmall‐fibre neuropathy with the impairment of thermal sensations is the most frequent sensory deficit in diabetes, and HbA1C is significantly associated with the elevated thermal thresholds. Copyright © 2007 John Wiley & Sons, Ltd.
Copper(II)–Purine Complexes Encapsulated in NaY Zeolite
Authors: Nunes Natércia , Amaro Raquel , Costa Filomena , Rombi Elisabetta , Carvalho M. Alice , Neves Isabel C. , Fonseca António M. 
Published: March 2007

AbstractY‐encapsulated CuII–purine complexes were synthesized, characterized and studied in the catalytic oxidation of cyclohexene. Encapsulation was achieved by ion‐exchanging the complex from aqueous solutions containing both the purine ligand, 9‐methyl‐6‐(methylamino)purine, and copper, in different pH, with a purine/CuII molar ratio of 5:1. The resulting materials were characterized by surface analysis (XPS, SEM and XRD), chemical analysis, spectroscopic methods (EPR, FTIR and UV/Vis) and thermal analysis (TGA), which indicated that the CuII–purine complexes were effectively encapsulated in NaY, most probably inside the supercages, without any modification of the morphology and structure of the zeolite. Different CuII–purine complexes were formed, depending on the pH during synthesis. The coordination geometry of Y‐encapsulated CuII–purine complexes was obtained with preferentially 1:2 and 1:3 Cu/L stoichiometry: complexes A and B (1:2) and complex C (1:3). Complex A was formed at pH ≥ 7, and complexes B and C (Scheme 2) were formed at pH = 5.4. Oxidation of cyclohexene with tBuOOH (TBHP) as the oxygen source, gave 2‐cyclohexene‐1‐one, 2‐cyclohexene‐1‐ol, cyclohexene oxide and 3‐tert‐butylcyclohexenyl peroxide. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Comparison between the Photophysical Properties of Pyrazolo‐ and Isoxazolo[60]fullerenes with Dual Donors (Ferrocene, Aniline and Alkoxyphenyl)
Authors: Perez Laura , El‐Khouly Mohamed E. , de la Cruz Pilar , Araki Yasuyuki , Ito Osamu , Langa Fernando 
Published: March 2007

AbstractTwo series of new pyrazolo‐ and isoxazolo[60]fullerenes covalently linked to vinylenephenylene bearing ferrocene, dibutylaniline or dodecyloxyphenyl electron‐donor groups attached in the periphery have been synthesized. The photophysical properties of these newly synthesized dual‐donor–C60 derivatives have been investigated and compared by applying time‐resolved fluorescence and nanosecond transient techniques in both polar and nonpolar solvents. Charge separation via the excited singlet state of C60 is more efficient in the pyrazolo‐C60 triads than in the isoxazolo‐C60 triads. It was found that the pyrazoline ring mediates charge separation as a result of the stronger electron‐donating character of the nitrogen atom of the pyrazoline ring compared with the oxygen atom of the isoxazoline ring. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
An Environmentally Friendly Oxidation System for the Selective Oxygenation of Aldimines to Oxaziridines with Anhydrous TBHP and Alumina‐Supported MoO3 as a Recyclable Heterogeneous Catalyst
Authors: Singhal Sweety , Jain Suman L. , Prasad V. V. D. N. , Sain Bir 
Published: March 2007

AbstractA highly efficient and selective protocol for the oxygenation of various aldimines to oxaziridines, which proceeds in excellent yields with enhanced selectivity by using alumina‐supported MoO3 as a recyclable heterogeneous catalyst and anhydrous TBHP as the ultimate oxidant, is described. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Inhibition of glutamine transport into mitochondria protects astrocytes from ammonia toxicity
Authors: Pichili V. B. R. , Rao K. V. Rama , Jayakumar A. R. , Norenberg M. D. 
Published: March 2007

AbstractHepatic encephalopathy (HE) is a major neurological complication that occurs in the setting of severe liver failure. Ammonia is a key neurotoxin implicated in this condition, and astrocytes are the principal neural cells histopathologically and functionally affected. Although the mechanism by which ammonia causes astrocyte dysfunction is incompletely understood, glutamine, a by‐product of ammonia metabolism, has been strongly implicated in many of the deleterious effects of ammonia on astrocytes. Inhibiting mitochondrial glutamine hydrolysis in astrocytes mitigates many of the toxic effects of ammonia, suggesting the involvement of mitochondrial glutamine metabolism in the mechanism of ammonia neurotoxicity. To determine whether mitochondriaare indeed the organelle where glutamine exerts its toxic effects, we examined the effect of L‐histidine, an inhibitor of mitochondrial glutamine transport, on ammonia‐mediated astrocyte defects. Treatment of cultured astrocytes with L‐histidine completely blocked or significantly attenuated ammonia‐induced reactive oxygen species production, cell swelling, mitochondrial permeability transition, and loss of ATP. These findings implicate mitochondrial glutamine transport in the mechanism of ammonia neurotoxicity. © 2007 Wiley‐Liss, Inc.
ATP‐induced chemotaxis of microglial processes requires P2Y receptor‐activated initiation of outward potassium currents
Authors: Wu Long‐Jun , Vadakkan Kunjumon I. , Zhuo Min 
Published: March 2007

AbstractMicroglial cells are the resident macrophages that are involved in brain injuries and infections. Recent studies using transcranial two‐photon microscopy have shown that ATP and P2Y receptors mediated rapid chemotactic responses of miroglia to local injury. However, the molecular mechanism for microglial chemotaxis toward ATP is still unknown. To address this question, we employed a combination of simultaneous perforated whole‐cell recordings and time‐lapse confocal imaging in GFP‐labeled microglia in acute brain slices from adult mice. We found that ATP‐induced rapid chemotaxis is correlated with P2Y receptor associated‐outward potassium current in microglia. Activation of both P2Y receptor and its associated potassium channels are required for ATP‐induced chemotaxis and baseline motility of microglial cells. The chemotaxis required the activation of phosphoinositide 3‐kinase but not mitogen‐activated protein kinase pathway. Our results provide strong evidence that P2Y receptor‐associated outward potassium channels and the phosphoinositide 3‐kinase pathway are important for ATP‐induced microglial motility in acute brain slices. © 2007 Wiley‐Liss, Inc.
Gangliosides contribute to stability of paranodal junctions and ion channel clusters in myelinated nerve fibers
Authors: Susuki Keiichiro , Baba Hiroko , Tohyama Koujiro , Kanai Kazuaki , Kuwabara Satoshi , Hirata Koichi , Furukawa Keiko , Furukawa Koichi , Rasband Matthew N. , Yuki Nobuhiro 
Published: March 2007

AbstractParanodal axo‐glial junctions are important for ion channel clustering and rapid action potential propagation in myelinated nerve fibers. Paranode formation depends on the cell adhesion molecules neurofascin (NF) 155 in glia, and a Caspr and contactin heterodimer in axons. We found that antibody to ganglioside GM1 labels paranodal regions. Autoantibodies to the gangliosides GM1 and GD1a are thought to disrupt nodes of Ranvier in peripheral motor nerves and cause Guillain‐Barré syndrome, an autoimmune neuropathy characterized by acute limb weakness. To elucidate ganglioside function at and near nodes of Ranvier, we examined nodes in mice lacking gangliosides including GM1 and GD1a. In both peripheral and central nervous systems, some paranodal loops failed to attach to the axolemma, and immunostaining of Caspr and NF155 was attenuated. K+ channels at juxtaparanodes were mislocalized to paranodes, and nodal Na+ channel clusters were broadened. Abnormal immunostaining at paranodes became more prominent with age. Moreover, the defects were more prevalent in ventral than dorsal roots, and less frequent in mutant mice lacking the b‐series gangliosides but with excess GM1 and GD1a. Electrophysiological studies revealed nerve conduction slowing and reduced nodal Na+ current in mutant peripheral motor nerves. The amounts of Caspr and NF155 in low density, detergent insoluble membrane fractions were reduced in mutant brains. These results indicate that gangliosides are lipid raft components that contribute to stability and maintenance of neuron‐glia interactions at paranodes. © 2007 Wiley‐Liss, Inc.
Bridge over troubled water: Protection against hepatitis C virus persistence?
Authors: Thimme Robert , Spangenberg Hans-Christian , Blum Hubert E. 
Published: March 2007

Background:
Neither previous hepatitis C (HCV) infection nor vaccination with HCV-derived antigens protects against reinfection. However, HCV infection and vaccination in chimpanzees has been shown to reduce the magnitude and duration of viraemia with re-challenge. We aimed to establish whether similar immunity could be achieved in man.

Methods:
From a study of injecting drug users, we identified 164 people who had no evidence of previous HCV infection and 98 individuals who had been previously, but were not currently, infected with HCV. We compared the incidence and persistence of HCV viraemia in these two groups over four consecutive 6-month periods.

Findings:
Of participants without previous HCV infection, the incidence of HCV infection was 21% (35/164). By contrast, people previously infected were half as likely to develop new viraemia (12% (12/98)), even after accounting for risk behaviour (hazard ratio, 0.45; 95% CI 0.23-0.88). Furthermore, in HIV-negative people, those previously infected were 12 times less likely than people infected for the first time to develop persistent infection (odds ratio 0.05, 95% CI 0.01-0.3), and median peak HCV RNA concentration was two logs lower. HCV persisted in six of six HIV-1 positive people, even in one man who had previously cleared HCV infection when he was HIV-1 negative.

Interpretation:
There is an alarming frequency of HCV infection and persistence among injecting drug users. Our data suggest that immunity against viral persistence can be acquired, and that vaccines should be tested to reduce the burden of HCV-related liver disease.