bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel route for synthesizing hyperbranched polyamine
Authors: Liu Jianhua , Ren Chun , Yang Zhu , Shi Wenfang 
Published: January 2007

AbstractA novel route for the synthesis of hyperbranched polyamine containing imidazolidine rings was developed, proceeding by the step‐growth polymerization of acrolein with ethylene diamine. The reaction kinetics and polymerization mechanism were studied with NMR and ultraviolet–visible spectroscopy. The influence of the reaction temperature and the concentration and feed ratio of the reactants on the structural characteristics of the obtained products was investigated. To obtain stable hyperbranched polyamines as analogues of hyperbranched poly(ethylene imine) or dendrimeric poly(propylene imine), sodium borohydride was used to reduce the synthesized hyperbranched polyamines to open the imidazolidine rings. The molecular weights, degrees of branching, and glass‐transition temperatures of the hyperbranched polyamines before and after reduction were compared. The polymerization behaviors of acrolein with other amines such as ethanol amine, propylene diamine, and 1,6‐hexane diamine were also investigated. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 699–708, 2007
Combining tight‐binding and molecular dynamics methods to model the behaviour of metals in the plastic regime
Authors: Bobrowski M. , Dziedzic J. , Rybicki J. 
Published: January 2007

AbstractUltra‐precision machining of metals, the breaking of nanowires under tensile stress and fracture of nanoscale materials are examples of technologically important processes which are both extremely difficult and costly to investigate experimentally. We describe a multiscale method for the simulation of such systems in which the energetically active region is modelled using a robust tight‐binding scheme and the rest of the system is treated with the molecular dynamics method. We introduce a computer code implementing the method, geared towards non‐equilibrium, cross‐scaled tight‐binding and molecular dynamics simulations. Apart from the presentation of the method and implementation, we discuss preliminary physical results obtained and discuss their validity. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Non‐finite‐difference algorithm for integrating Newton's motion equations
Authors: Brzostowski B. , Dudek M. R. , Grabiec B. , Nadzieja T. 
Published: January 2007

AbstractWe have presented some practical consequences on the molecular‐dynamics simulations arising from the numerical algorithm published recently in paper [1]. The algorithm is not a finite‐difference method and therefore it could be complementary to the traditional numerical integrating of the motion equations. It consists of two steps. First, an analytic form of polynomials in some formal parameter λ (we put λ = 1 after all) is derived, which approximate the solution of the system of differential equations under consideration. Next, the numerical values of the derived polynomials in the interval, in which the difference between them and their truncated part of smaller degree does not exceed a given accuracy ε become the numerical solution. The particular examples, which we have considered, represent the forced linear and nonlinear oscillator and the 2D Lennard–Jones fluid. In the latter case we have restricted to the polynomials of the first degree in formal parameter λ.The computer simulations play very important role in modeling materials with unusual properties being contradictictory to our intuition. The particular example could be the auxetic materials. In this case, the accuracy of the applied numerical algorithms as well as various side‐effects, which might change the physical reality, could become important for the properties of the simulated material. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On simultaneous positive and negative Poisson's ratio laminates
Authors: Lim Teik‐Cheng 
Published: January 2007

AbstractStudies on the mechanical behavior of materials are often performed on the assumption of positive Poisson's ratio except for auxetic materials. Auxetic materials and structures are intriguing systems that exhibit negative Poisson's ratio. Recently some investigation were made on semi‐auxetic materials in terms of their directional and positional auxeticity. In this paper we furnish a simple example of a 3‐ply laminate consisting of isotropic plies whereby the sign of its effective Poisson's ratio changes when the loading mode changes between pure axial loading and pure bending. In addition, both positive and negative Poisson ratio behaviors do not cancel one another, but are simultaneously manifested when the above‐mentioned loading modes are combined. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
QSPR Modeling of Heats of Combustion for Carboxylic Acids
Authors: Duchowicz Pablo R. , Garro Juan C. M. , Andrada Matías F. , Castro Eduardo A. , Fernández Francisco M. 
Published: January 2007

AbstractIn the present study, the predictions for heats of combustion achieved with a modified Kharash model are compared with results obtained from the QSPR theory. The homogeneous set of carboxylic acids investigated comprises 52 compounds, and a pool of 1202 theoretically defined molecular descriptors provided by the software Dragon 5 are explored using both the Forward Stepwise Regression technique and the new proposed Replacement Method procedure. Final results suggest that the linear regression analyses employed are not able to lead to a better quality model.
In Silico ADME Modeling 3: Computational Models to Predict Human Intestinal Absorption Using Sphere Exclusion and kNN QSAR Methods
Authors: Gunturi Sitarama B. , Narayanan Ramamurthi 
Published: January 2007

AbstractModeling of human intestinal absorption (HIA) data of 175 diverse drugs and 336 calculated descriptors is performed to develop global predictive models that are applicable to the whole medicinal chemistry space. With this aim, we employed two automated procedures, (a) Sphere Exclusion Algorithm (SEA) to select members of the training and test sets based on structural dissimilarity and (b) k‐Nearest Neighbors (kNN) method along with Genetic Algorithms (kNN‐QSAR‐GA) to select significant and independent descriptors. This methodology helped us to derive optimal Quantitative Structure–Property Relationship (QSPR) models based on three and four descriptors. The best three descriptor model is based on Delta Chi Index of order 3 (Cluster), Hydrogen type E‐State index ShsOH, AlogP99 ($\rm{ q_{{\rm{LOO}}}^2 }$=0.7401 and $\rm{ q_{{\rm{ext}}}^2 }$=0.7989); the best four variable model is based on auto‐correlation descriptor (Moran) weighted by atomic weights – order 7, AI‐State_Indices_AISssssC, number of hydrogen bond acceptors, AlogP99 ($\rm{ q_{{\rm{LOO}}}^2 }$=0.8196 and $\rm{ q_{{\rm{ext}}}^2 }$=0.6999). Based on extensive validation tests of the models M1–M4, comparison of their overall performance and $\rm{ q_{{\rm{ext}}}^2 }$ statistics with reported models using other approaches, it is shown that: (a) the models have high stability and are robust and (b) for the first time in HIA modeling, the combination of an automated training set selection (SEA) followed by variable selection (kNN‐QSAR_GA) is shown to be a promising methodology to build multiple stable models that are useful in consensus prediction. From the analysis of the physical meaning of the selected descriptors, it is inferred that the HIA of small organic compounds can be accurately predicted using calculated descriptors that code for the following fundamental properties: (1) lipophilicity, (2) hydrogen bonding capacity, (3) size, and (4) shape and further, the role of new calculated descriptors on the HIA profile of small organic compounds is uncovered. Finally, as the models reported herein are based on computed properties, they appear to be a valuable tool in virtual screening, where selection and prioritization of candidates is required.
NO migration from N‐methyl‐N‐nitrosobenzene‐sulfonamide to 3,6‐dibromocarbazole: Concerted or stepwise reaction path?
Authors: Zhang Dongju , Sun Hui , Wang Fang , Liu Chengbu 
Published: January 2007

AbstractThe NO migration from N‐methyl‐N‐nitrosobenzene‐sulfonamide to 3,6‐dibromocarbazole was proposed in a recent literature to follow a stepwise reaction path. However, the present density functional theory calculations at the MP2/6–31G(d,p)//B3LYP/6–31G(d,p) level show that this reaction exclusively proceeds via a concerted mechanism involving a four‐membered ring transition state. The calculated barrier is in good agreement with the experimental finding. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
A repeated measures concordance correlation coefficient
Authors: King Tonya S. , Chinchilli Vernon M. , Carrasco Josep L. 
Published: January 2007

AbstractThe concordance correlation coefficient is commonly used to assess agreement between two raters or two methods of measuring a response when the data are measured on a continuous scale. However, the situation may arise in which repeated measurements are taken for each rater or method, e.g. longitudinal studies in clinical trials or bioassay data with subsamples. This paper proposes a coefficient for measuring agreement between two raters or two methods of measuring a response in the presence of repeated measurements. We illustrate the methodology with examples comparing (1) 1‐hr versus 2‐hr blood draws for measuring cortisol in an asthma clinical trial and (2) two measurements of percentage body fat, from skinfold calipers and dual energy X‐ray absorptiometry. Copyright © 2007 John Wiley & Sons, Ltd.
Experimental investigation on weather cues for mast seeding of Fagus crenata
Authors: Kon Hirokazu , Noda Takashi 
Published: January 2007

AbstractAlthough a recent study has suggested that the minimum temperature from late April to mid‐May in the year preceding flowering causes mast seeding in Fagus crenata, no direct evidence is available to support this finding. The aim of the present investigation was, therefore, to test – in a field experiment – whether the minimum temperature determines mast seeding in F. crenata. We examined the effect of nighttime temperatures on flower‐bud initiation in F. crenata by enclosing fruit‐bearing branches in heated bags at night, thereby maintaining average nighttime temperatures of approximately 2°C above the ambient temperatures. Heating was applied at night from 21 April to 20 May, 21 May to 19 June, and 21 April to 19 June in 2001. Female inflorescence initiation was inhibited by the nocturnal heating in the period 21 April to 20 May and 21 May to 19 June. However, nocturnal heating from 21 April to 20 May was the more important based on the odds ratio of the former being much lower than that of the latter in a logistic regression model. Male inflorescence initiation was also inhibited by nocturnal heating from 21 April to 20 May. We therefore conclude that flower‐bud initiation in F. crenata was controlled by nighttime temperatures between 21 April and 20 May.
Prevalence of ECG abnormalities in an international survey of patients with suspected or confirmed heart failure at death or discharge
Authors: Khan Nasrin K. , Goode Kevin M. , Cleland John G.F. , Rigby Alan S. , Freemantle Nick , Eastaugh Joanne , Clark Andrew L. , de Silva Ramesh , Calvert Melanie J. , Swedberg Karl , Komajda Michael , Mareev VIu , Follath Ferenc ,   EuroHeart Failure Survey Investigators
Published: January 2007

AbstractBackgroundMost patients suspected of having heart failure (HF) will get a 12‐lead electrocardiogram (ECG) but its utility for excluding HF or assisting in its management has rarely been investigated.MethodsThe EuroHeart Failure survey identified 11,327 patients hospitalised with a suspected diagnosis of HF from 115 hospitals in 24 countries. ECGs were obtained from 9315 patients, of whom 5934 had cardiac imaging tests. The utility of the ECG was assessed for excluding or diagnosing major structural heart disease (MSHD) or major left ventricular systolic dysfunction (MLVSD) and for therapeutic decision making.FindingsMSHD was present in 70% and MLVSD in 54% of patients overall but in only 21% and 5%, respectively, if the ECG was entirely normal. However, <2% of patients had a normal ECG. No single ECG characteristic identified a probability <25% of MSHD or <20% of MLVSD. Patients with QRS width ≥120 ms or anterior pathological Q‐waves had a probability >80% of MSHD and >70% of MLVSD. Diagnostic models suggested that electrocardiographic criteria alone were not accurate for the diagnosis or exclusion of important heart disease in this population. However, 2468 patients (42%) had an electrocardiographic finding that should be used to guide the choice of therapy.ConclusionsA normal ECG is rare in patients with suspected HF but has limited diagnostic value in this setting. The ECG has an important role in guiding therapy.
Health-enhancing physical activity among Saudi adults using the International Physical Activity Questionnaire (IPAQ)
Authors: Al-Hazzaa Hazzaa M 
Published: January 2007

AbstractObjectivesTo describe the physical activity profile of Saudi adults living in Riyadh, using the International Physical Activity Questionnaire (IPAQ) short-version telephone format.MethodsPhysical activity was assessed using the official Arabic short form of IPAQ, intended for use in telephone interview. The instrument asks for times spent in walking, moderate- and vigorous-intensity physical activity of at least 10 min duration. The sample consisted of 1616 Saudis, between 15 and 78 years of age, living in Riyadh. Participants were drawn from a list of names in the telephone book using a simple random method. Telephone interviews were administered during the spring of 2003 by trained male interviewers.ResultsThe final sample size was 1064 Saudi males and females (response rate of 66%), with males comprising about 66% of the respondents. Over 43% of Saudis did not participate in any type of moderate-intensity physical activity lasting for at least 10 min. More than 72% of the sample did not engage in any type of vigorous-intensity physical activity lasting for at least 10 min. The proportion of Saudis who walked for 150 min or more per week was 33.3%. Females were engaged more in moderate physical activity than males, whereas males participated more in vigorous activity compared with females. Activity levels did not show significant relationships with education level or job hours per week. Based on the three activity categories established by IPAQ, 40.6% of Saudis were inactive, 34.3% were minimally active and 25.1% were physically active. Physical inactivity increased with advancing age.ConclusionThe data suggest that the prevalence of physical inactivity among Saudis adults is relatively high. Efforts are needed to encourage Saudis to be more physically active, with the goal of increasing the proportion of Saudis engaging in health-enhancing physical activity.
Impact of parental education and income inequality on children's food intake
Authors: Sausenthaler Stefanie , Kompauer Iris , Mielck Andreas , Borte Michael , Herbarth Olf , Schaaf Beate , von Berg Andrea , Heinrich Joachim ,   for the LISA Study Group
Published: January 2007

AbstractObjectiveTo analyse the association between socio-economic indicators and diet among 2-year-old children, by assessing the independent contribution of parental education and equivalent income to food intake.DesignThe analysis was based on data from a prospective birth cohort study. Information on diet was obtained using a semi-quantitative food-frequency questionnaire. Low and high intake of food was defined according to the lowest and the highest quintile of food consumption frequency, respectively.SettingFour German cities (Munich, Leipzig, Wesel, Bad Honnef), 1999–2001.SubjectsSubjects were 2637 children at the age of 2 years, whose parents completed questionnaires gathering information on lifestyle factors, including parental socio-economic status, household consumption frequencies and children's diet.ResultsBoth low parental education and low equivalent income were associated with a low intake of fresh fruit, cooked vegetables and olive oil, and a high intake of canned vegetables or fruit, margarine, mayonnaise and processed salad dressing in children. Children with a low intake of milk and cream, and a high intake of hardened vegetable fat, more likely had parents with lower education. Low butter intake was associated with low equivalent income only.ConclusionsThese findings may be helpful for future intervention programmes with more targeted policies aiming at an improvement of children's diets.
Fruit and vegetable consumption and self-reported functional health in men and women in the European Prospective Investigation into Cancer–Norfolk (EPIC–Norfolk): a population-based cross-sectional study
Authors: Myint Phyo K , Welch Ailsa A , Bingham Sheila A , Surtees Paul G , Wainwright Nicholas WJ , Luben Robert N , Wareham Nicholas J , Smith Richard D , Harvey Ian M , Day Nicholas E , Khaw Kay-Tee 
Published: January 2007

AbstractObjectivesTo investigate the association between fruit and vegetable consumption and self-reported physical and mental functional health measured by an anglicised short-form 36-item questionnaire (UK SF-36).DesignPopulation-based cross-sectional study.SettingGeneral community in Norfolk, UK.SubjectsA total of 16 792 men and women aged 40–79 years recruited from general practice population registers as part of the European Prospective Investigation into Cancer (EPIC)–Norfolk study, who completed food-frequency questionnaires in 1993–1997 and Health and Life Experiences Questionnaires 18 months later, were enrolled in the study.ResultsMean SF-36 physical component summary scores increased significantly with increasing total fruit and vegetable consumption in both men and women (P < 0.0001 for trend). Men and women in the top quartile of consumption compared with the bottom quartile had a significantly higher likelihood of reporting good physical health (defined as a score ≥ 55); odds ratio (OR) 1.30, 95% confidence interval (CI) 1.11–1.53 for men and OR 1.28, 95% CI 1.11–1.48 for women, after controlling for age, body mass index, smoking, education, social class, prevalent illness and total energy intake. Exclusion of current smokers and people with prevalent illness did not alter the associations.ConclusionHigher fruit and vegetable consumption is associated with better self-reported physical functional health within a general population. Increasing daily intake by two portions of fruit and vegetables was associated with an 11% higher likelihood of good functional health. Since the current average consumption of fruit and vegetables in the UK is about three portions, the recommended ‘five a day’ strategy may have additional benefit for functional as well as other health outcomes in the population.
4‐S‐Cysteaminylphenol‐loaded magnetite cationic liposomes for combination therapy of hyperthermia with chemotherapy against malignant melanoma
Authors: Ito Akira , Fujioka Masatake , Yoshida Tatsuro , Wakamatsu Kazumasa , Ito Shosuke , Yamashita Toshiharu , Jimbow Kowichi , Honda Hiroyuki 
Published: January 2007

Tyrosine analogs are good candidates for developing melanoma chemotherapies because melanogenesis is inherently toxic and expressed uniquely in melanocytic cells. The sulfur homolog of tyrosine, 4‐S‐cysteaminylphenol (4‐S‐CAP), was shown to be a substrate of melanoma tyrosinase and can cause selective cytotoxicity of melanocytes and melanoma cells. Previously, in order to improve the adsorption of magnetite nanoparticles to target cell surfaces, and generate heat in an alternating magnetic field (AMF) for cancer hyperthermia, we produced hyperthermia using magnetite cationic liposomes (MCL) that have a positive charge at the liposomal surface. In the present study, we constructed 4‐S‐CAP‐loaded MCL (4‐S‐CAP/MCL), which act as a novel modality, combining melanoma‐specific chemotherapy by 4‐S‐CAP with intracellular hyperthermia mediated by MCL. The 4‐S‐CAP/MCL exerted 4‐S‐CAP‐mediated anticancer effects on B16 melanoma cells in vitro and in vivo. Moreover, after intratumoral injection of 4‐S‐CAP/MCL in vivo, the melanoma nodules were heated to 45°C under an AMF. Significantly higher therapeutic effects were observed in mice treated with the combination therapy mediated by 4‐S‐CAP/MCL plus AMF irradiation compared with mice treated with 4‐S‐CAP/MCL alone (without AMF) or mice treated with hyperthermia alone (MCL + AMF irradiation). These results suggest that this novel therapeutic tool is applicable to the treatment of malignant melanoma. (Cancer Sci 2007; 98: 424–430)
Specific overexpression of OLFM4GW112/hGC−1 mRNA in colon, breast and lung cancer tissues detected using quantitative analysis
Authors: Koshida Saori , Kobayashi Daisuke , Moriai Ryosuke , Tsuji Naoki , Watanabe Naoki 
Published: January 2007

Overexpression of the olfactomedin 4 (OLFM4GW112,/hGC−1) gene was recently reported to inhibit various apoptotic pathways and promote proliferation of cancer cells, suggesting that OLFM4 might serve as a diagnostic marker for human cancers. Therefore, we examined cancer‐specific OLFM4 overexpression. OLFM4 mRNA was highly expressed in cancerous tissues obtained from the colon, breast and lung. Positivity for OLFM4 mRNA, defined as the mean + 2 SD in non‐cancerous colon and breast tissues, was observed in 68 and 50% of the studied colon and breast cancer tissues. OLFM4 mRNA expression was not detected in non‐cancerous lung tissues but was evident in 62% of the lung cancer tissues. On comparing paired samples, the expression of OLFM4 mRNA was observed to be elevated in 90, 69 and 85% of colon, breast and lung cancer tissues, respectively. OLFM4 mRNA expression was observed even in the early stages of each cancer type. The expression of OLFM4 mRNA did not correlate with that of the antiapoptotic molecule survivin, indicating that it can be used independently in cancer diagnosis. Combining OLFM4 and survivin resulted in higher positivity. Thus, OLFM4 mRNA might be a useful tool to support the diagnosis of cancer, irrespective of the clinical stages. (Cancer Sci 2007; 98: 315–320)
Amrubicin, a novel 9‐aminoanthracycline, enhances the antitumor activity of chemotherapeutic agents against human cancer cells in vitro and in vivo
Authors: Hanada Mitsuharu , Noguchi Toshihiro , Yamaoka Takashi 
Published: January 2007

Amrubicin, a completely synthetic 9‐aminoanthracycline derivative, is an active agent in the treatment of untreated extensive disease‐small‐cell lung cancer and advanced non‐small‐cell lung cancer. Amrubicin administered intravenously at 25 mg/kg substantially prevented the growth of five of six human lung cancer xenografts established in athymic nude mice, confirming that amrubicin as a single agent was active in human lung tumors. To survey which antitumor agent available for clinical use produces a synergistic interaction with amrubicin, we examined the effects in combinations with amrubicinol, an active metabolite of amrubicin, of several chemotherapeutic agents in vitro using five human cancer cell lines using the combination index (CI) method of Chou and Talalay. Synergistic effects were obtained on the simultaneous use of amrubicinol with cisplatin, irinotecan, gefitinib and trastuzumab, with CI values after 3 days of exposure being <1. Additive effect was observed with the combination containing vinorelbine with CI values indistinguishable from 1, while the combination of amrubicinol with gemcitabine was antagonistic. All combinations tested in vivo were well tolerated. The combinations of cisplatin, irinotecan, vinorelbine, trastuzumab, tegafur/uracil, and to a lesser extent, gemcitabine with amrubicin caused significant growth inhibition of human tumor xenografts without pronouncedly enhancing body weight loss, compared with treatment using amrubicin alone at the maximum tolerated dose. Growth inhibition of tumors by gefitinib was not antagonized by amrubicin. These results suggest that amrubicin appears to be a possible candidate for combined use with cisplatin, irinotecan, vinorelbine, gemcitabine, tegafur/uracil or trastuzumab. (Cancer Sci 2007; 98: 447–454)