bluuebunny/crossref_metadata_2025_split huggingface dataset:
Heterocyclic Chemistry of Sulfur Chlorides – Fast Ways to Complex Heterocycles
Authors: García‐Valverde María , Torroba Tomás 
Published: December 2005

AbstractThis microreview highlights the most important advances in the synthetic applications of sulfur dichloride and disulfur dichloride for the preparation of heterocycles. Sulfur chlorides can be considered some of the best sulfur‐transfer reagents for the synthesis of heterocyclic systems. Their high reactivity towards nucleophilic organic compounds such as alkenes, alkynes, amines, nitriles, oximes, and their both chlorinating and sulfurating character explain the extensive use of these reagents. In many cases, the initial reactions give rise to reactive intermediates that can be trapped by nucleophiles in a tandem fashion, expanding the possibilities of the reactions. In this way, several new heterocyclic systems can be obtained by a careful selection of the appropriate combination of reagents. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Ion‐pair association and acid–base equilibria in nonaqueous capillary electrophoresis of weakly basic compounds
Authors: Carabias‐Martínez Rita , Rodríguez‐Gonzalo Encarnación , Hernández‐Méndez Jesús , Cruz Edith Miranda , Domínguez‐Álvarez Javier 
Published: December 2005

AbstractCE in nonaqueous media was used to study the migrating behavior of two weakly basic s‐triazine pesticides and one of their metabolites. The target pesticides were selected to be representative for each of the two main groups: propazine and deethylatrazine for the chloro‐s‐triazines group and ametryn for the methylthio‐s‐triazines group. To elucidate the phenomena involved, systematic studies were carried out in the different organic media studied. Absolute mobilities were determined in 50% v/v methanol (MeOH)/ACN by extrapolation of the effective mobilities to zero ionic strength in the presence of different concentrations of perchloric acid. Conductivity measurements performed in MeOH and 50 and 20% v/v methanol/ACN permitted the evaluation of the associations of the components of the BGE. The effects of ionic strength on the actual mobilities of the compounds were determined in the presence of perchloric acid and SDS in different organic media. Two different ion‐pair equilibria were considered: one due to the presence of perchlorate anions present in the BGE and second that from the added dodecyl sulfate anions. Bearing in mind that these weakly basic compounds can exhibit ion‐pair and acid–base equilibria, the acid–base and ion‐pair parasite reaction coefficients were determined. Finally, the effects of ionic strength, ion‐pair interactions and acid–base properties on the effective electrophoretic mobilities of the analytes are discussed.
An inexpensive microslab gel DNA electrophoresis system with real‐time fluorescence detection
Authors: Chen Xiaojia , Ugaz Victor M. 
Published: December 2005

AbstractIn this paper, we describe the construction of a simple yet powerful gel electrophoresis apparatus that can be used to perform size‐selective separations of DNA fragments in virtually any laboratory. This system employs a microslab gel format with a novel gel casting technique that eliminates the need for delicate combs to define sample loading wells. The compact size of the microslab gel format allows rapid separations to be performed at low voltages using submicroliter sample volumes. Real time fluorescence detection of the migrating DNA fragments is accomplished using an inexpensive digital microscope that directly connects to any PC with a USB interface. The microscope is readily adaptable for this application by replacing its white light source with a blue light‐emitting diode (LED) and adding an appropriate emission filter. Both polyacrylamide and agarose gels can be used as separation matrices. Separation performance was characterized using standard dsDNA ladders, and correct sizing of a 191 bp PCR product was achieved in 15 min. The low cost and simplicity of this system makes it ideally suited for use in a variety of laboratory and educational settings.
Ionizing radiation and leukaemia: more questions than answers
Authors: Wright Eric G 
Published: December 2005

AbstractThe mechanisms underlying the unequivocal association between ionizing radiation and the development of leukaemia remain unknown. Recent progress in defining sub‐cellular events has contributed to our understanding of the production of genetic lesions in irradiated cells but the importance of tissue effects in response to radiation damage has attracted much less attention. Thus, genetic lesions induced by radiation are considered to result from the deposition of energy in the cell nucleus and the initiating lesion for radiation‐induced transformation has been similarly attributed to direct DNA damage. Recently, however, there have been many reports of radiation effects, characteristically associated with the consequences of energy deposition in the cell nucleus, arising in non‐irradiated cells as a consequence of communication with irradiated cells. These, so‐called, non‐targeted radiation effects pose major challenges to current views of the mechanisms of radiation‐induced DNA damage and the mechanisms underlying radiogenic malignancies. Considered together with data obtained from laboratory model systems, a rather complex picture of radiation leukaemogenesis is emerging in which, additional to any damage induced directly in target stem cells, the haemopoietic microenvironment can be a source of damaging signals and cellular interactions make important genotype‐dependent contributions to determining overall outcome after radiation exposures. Copyright © 2005 John Wiley & Sons, Ltd.
Detection rates of high‐grade prostate cancer during subsequent screening visits. Results of the European Randomized Screening Study for Prostate Cancer
Authors: van der Kwast Theodorus H. , Ciatto Stefano , Martikainen Paula M. , Hoedemaeker Robert , Laurila Marita , Pihl Carl‐Gustaph , Hugosson Jonas , Neetens Ingrid , Nelen Vera , Di Lollo Simonetta , Roobol Monique J. , Määtänen Liisa , Santonja Carlos , Moss Sue , Schröder Fritz H. 
Published: December 2005

AbstractScreening for prostate cancer using prostate‐specific antigen (PSA) tests has led to a stage and grade shift as compared to the pre‐PSA era. Effectiveness of screening for prostate cancer should be manifested by a reduction in detection rate of aggressive cancers during subsequent screening. In 6 centers of the European Randomized Screening study for Prostate Cancer, a total of 58,710 men were tested for prostate cancer. Screening centers differed with regard to age‐range, screening interval and biopsy indications. During the 2nd visit, the proportion of Gleason score 6 cancers increased from 62.5 to 75%, mainly at the expense of Gleason score 7 cancers. High‐grade (Gleason score 8–10) cancer detection rates varied per screening center during the 1st visit from 5.1 to 41.1, and during the 2nd visit from 6.4 to 29.3/10,000 men. The overall detection rate of high‐grade cancers showed a reduction during the 2nd visit from 26 to 12/10,000 men, an effect mainly attributable to the screening center with the highest cancer detection rate (i.e. 507/10,000 men). Variations in detection rates among screening centers related among others to biopsy compliance and age range. © 2005 Wiley‐Liss, Inc.
Frequent EGFR mutations in noninvasive bronchioloalveolar carcinoma
Authors: Matsumoto Shingo , Iwakawa Reika , Kohno Takashi , Suzuki Kenji , Matsuno Yoshihiro , Yamamoto Seiichiro , Noguchi Masayuki , Shimizu Eiji , Yokota Jun 
Published: December 2005

AbstractMutations of the epidermal growth factor receptor gene (EGFR) have been reported to be present in a considerable fraction of lung adenocarcinomas showing dramatic response to EGFR tyrosine kinase inhibitors. To clarify pathogenic significance of the mutations for the development of lung adenocarcinoma, we investigated stage I lung adenocarcinomas for the mutations. First, 107 cases of macrodissected stage I adenocarcinomas were examined for mutations in exons 18–21 of the EGFR gene. EGFR mutations were detected in 36 of the 107 cases (34%). In particular, among the stage I cases, the mutations were detected in 17 of 42 small‐sized adenocarcinomas (≤2 cm in diameter) (40%), including 7 of 11 noninvasive bronchioloalveolar carcinomas (BACs) (64%) and 7 of 25 invasive adenocarcinomas with BAC components (28%). Second, 26 cases of laser capture microdissected small‐sized adenocarcinomas, including 9 cases in the first analysis, were examined for the mutations. Reanalysis of microdissected materials in the 9 cases identified the mutations in 2 more adenocarcinomas with BAC components. Moreover, in the analysis of the other 17 microdissected materials, EGFR mutations were detected in 7 of 12 BACs (58%) and in 3 of 5 adenocarcinomas with BAC components (60%). EGFR mutations are present frequently in BACs, and are thus likely to be a critical genetic alteration for the formation of noninvasive lung adenocarcinoma. © 2005 Wiley‐Liss, Inc.
Lung cancer risk and occupational exposure to meat and live animals
Authors: Durusoy Raika , Boffetta Paolo , Mannetje Andrea 't , Zaridze David , Szeszenia‐Dabrowska Neonila , Rudnai Peter , Lissowska Jolanta , Fabiánová Eleonóra , Cassidy Adrian , Mates Dana , Bencko Vladimir , Salajka Frantisek , Janout Vladimir , Fevotte Joelle , Fletcher Tony , Brennan Paul 
Published: December 2005

AbstractAn increased risk of lung cancer has been reported for butchers and meat workers in several cohort studies, although confounding from tobacco smoking could not be ruled out in any of these studies. These exposures, as well as a potential risk associated with contact with live animals, are addressed here in a large case–control study with full adjustment for smoking. More than 5,900 subjects were included in a case–control study conducted in 7 European countries. For each job they employed local experts who assessed the exposure to a number of occupational agents, including (i) meat aerosols and (ii) live animals, on the basis of detailed occupational questionnaires. Information on tobacco consumption and other risk factors was also collected. A small increased risk of lung cancer was observed with exposure to meat aerosols, after adjusting for smoking, (odds ratio (OR) = 1.27, 95% confidence interval (CI): 0.92, 1.75), which was most apparent for the upper tertile of cumulative exposure (OR = 1.73, 95% CI: 1.03, 2.92). A similar overall effect was observed for exposure to live animals, with an increased risk observed for a high frequency of exposure, (OR = 1.69, 95% CI: 1.21, 2.36) and a high intensity of exposure, (OR = 1.85, 95% CI: 1.16, 2.94), with significant trends for increasing frequency (p = 0.012), intensity (p = 0.015) and cumulative exposure (p = 0.024). In conclusion, this study provides evidence for an association between exposure to meat aerosols and lung cancer apparent in the highest tertile of exposure. The authors identified a more consistent association with exposure to live animals. © 2005 Wiley‐Liss, Inc.
In vitro antibacterial and cytotoxicity assay of multilayered polyelectrolyte‐functionalized stainless steel
Authors: Shi Z. , Neoh K.G. , Zhong S.P. , Yung L.Y.L. , Kang E.T. , Wang W. 
Published: December 2005

AbstractInfection of implanted materials by bacteria constitutes one of the most serious complications following prosthetic and implant surgery. In the present study, a new strategy for confering stainless steel with antibacterial property via the alternate deposition of quaternized polyethylenimine (PEI) or quaternized polyethylenimine‐silver complex and poly(acrylic acid) (PAA) was investigated. The success of the deposition of the polyelectrolyte multilayers (PEM) and its chemical nature was investigated by static water contact angle and X‐ray photoelectron spectroscopy (XPS), respectively. The antibacterial activity was assessed using Escherichia coli (E. coli, a gram‐negative bacterium) and Staphylococcus aureus (S. aureus, a gram‐positive bacterium). The inhibition of E. coli and S aureus growth on the surface of functionalized films was clearly shown using the LIVE/DEAD Baclight bacterial viability kits and fluorescence microscopy. The cytotoxicity of the PEM to mammalian cells, evaluated by the MTT assay, was shown to be minimal and long‐term antibacterial efficacy can be maintained. These results indicate new possibilities for the use of such easily built and functionalized architectures for the functionalization of surfaces of implanted medical devices. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
Electron group functions for the analysis of the electronic structures of molecules
Authors: Tokmachev A. M. , Dronskowski R. 
Published: December 2005

AbstractThe electronic structure of a vast majority of molecular systems can be understood in terms of electron groups and their wave functions. They serve as a natural basis for bringing intuitive chemical and physical concepts into quantum chemical calculations. This article considers the general electron group functions formalism as well as its simple geminal version. We try to characterize the wave function with the group structure and its capabilities in actual calculations. For this purpose we implement a variational method based on the wave function in the form of an antisymmetrized product of strongly orthogonal group functions and perform a series of electronic structure calculations for small molecules and model systems. The most important point studied is the relation between the choice of electron groups and the results obtained. We consider energetic characteristics as well as optimal geometry parameters. In view of practical importance, the structure of variationally optimized local one‐electron states is considered in detail as well as intuitive characteristics of chemical bonds. © 2005 Wiley Periodicals, Inc. J Comput Chem 27: 296–308, 2006
1‐methyl‐4‐phenylpyridinium neurotoxicity is attenuated by adenoviral gene transfer of human Cu/Zn superoxide dismutase
Authors: Barkats Martine , Horellou Philippe , Colin Philippe , Millecamps Stéphanie , Faucon‐Biguet Nicole , Mallet Jacques 
Published: December 2005

AbstractOxidative stress has been suggested to be an important mediator of dopaminergic cell death in Parkinson's disease (PD). We investigated the neuroprotective potential of Cu/Zn superoxide dismutase (SOD1) overexpression in the rat substantia nigra (SN) following adenovirus‐mediated gene transfer. Human dopaminergic SK‐N‐SH cells were transduced with adenoviral vectors expressing either human SOD1 (Ad‐SOD1) or β‐galactosidase (Ad‐βgal) before exposure to 1 mM of the 1‐methyl‐4‐phenylpyridinium ion (MPP+). A strong neuroprotective effect of SOD1 gene transfer was observed in the SK‐N‐SH cells exposed to MPP+ compared with controls. Adult rats were then given unilateral injections of either Ad‐SOD1 or Ad‐βgal into the striatum, and MPP+ was administered 8 days later at the same location. Strong transgene expression was detected in the SN dopaminergic neurons, a consequence of retrograde axonal transport of the adenoviral particles. The amphetamine‐induced rotational behavior of the rats was markedly lower in Ad‐SOD1‐injected rats than in control animals. Also, behavioral recovery significantly correlated with the number of tyrosine hydrolase‐expressing neurons in the SN of the treated rats. These results are consistent with oxidative stress contributing to the MPP+‐induced neurodegenerative process. They also indicate that SOD1 gene transfer into the nigrostriatal system may be a potential neuroprotective strategy for treating PD. © 2005 Wiley‐Liss, Inc.
Differential expression of lysophosphatidic acid receptor‐2 in intestinal and diffuse type gastric cancer
Authors: Yamashita Hiroharu , Kitayama Joji , Shida Dai , Ishikawa Makoto , Hama Kotaro , Aoki Junken , Arai Hiroyuki , Nagawa Hirokazu 
Published: December 2005

AbstractBackground and ObjectivesLysophosphatidic acid (LPA), a natural phospholipid, can modulate diverse cellular responses through LPA receptor, LPA1–4. Although LPA1 is known to be widely expressed in human tissues, the distribution of other LPA receptors is not characterized in malignant tissues. Recently, it was reported that malignant transformation resulted in aberrant expression of LPA2 in a various type of cancer, suggesting the positive role of LPA2 in tumor development.MethodsWe investigated the expression of the LPA2 receptor immunohistochemically in 204 gastric cancers and analyzed the relationship between the expression of LPA2 and clinicopathological features.ResultsLPA2 was preferentially expressed (67%) in intestinal‐type cancer that was significantly higher than that in diffuse‐type cancer (32%, P < 0.0001). The expression of LPA2 showed correlation with a higher rate of lymphatic and venous invasion, lymphatic metastasis, and resultingly tumor stage in diffuse‐type cancer, but not in intestinal‐type cancer.ConclusionsOur results highlight the possibility that LPA2 expression is an important process in the carcinogenesis of gastric cancer, especially in intestinal‐type cancer. Since LPA can transactivate HGF receptor (c‐Met) as well as EGF‐receptor, LPA may promote the progression of gastric cancer in diffuse‐type with high expression of c‐Met. The development of LPA2‐specific antagonists might have future therapeutic relevance in the treatment as well as prevention of gastric cancer. J. Surg. Oncol. 2006;93:30–35. © 2005 Wiley‐Liss, Inc.
Real‐Time NMR. How Fast Can We Do It?
Authors: Litvinov Victor M. , Dias Aylvin A. 
Published: December 2005

AbstractNetwork structure development during cross‐linking photopolymerization of polyethylene glycol di‐acrylate and its mixture with a mono‐functional 2‐ethylhexyl acrylate was studied using real‐time proton NMR T2 relaxation analysis. The time resolution of the method is typically in the order of seconds. The results reveal largely heterogeneous origin of network build up at the intermediate stages of photocuring. Domains of nano‐gel are already formed on initial stages of UV‐curing where hardly any change in viscosity is observed. Upon increasing curing time the fraction of gel increases at the expence of sol, the molar mass of network chains decreases and the molar mass of sol increases. The presence of mono‐acrylate slows down the curing rate. The curing continues after UV‐illumination causing a significant increase in the amount of gel and cross‐link density in the gel. Thus, the NMR method is a valuable tool for characterization of the kinetics of photopolymerization, the development of molecular structure and the resultant molecular scale heterogeneity during photocuring.
What are the supportive structures of the female urethra?
Authors: Fritsch Helga , Pinggera Germar Michael , Lienemann Andreas , Mitterberger Michael , Bartsch Georg , Strasser Hannes 
Published: December 2005

AbstractAimsFemale stress urinary incontinence is thought to result from impairment of the connective tissue “ligaments” of the urethra. Surgical repair of female incontinence mainly involves fixation of the urethra to the pubic bone or other surrounding structures. In the present anatomical‐radiological study, the anatomy of the connective tissue structures around the female urethra was investigated to determine the anatomical structures that support the urethra and the rhabdosphincter.Materials and MethodsThe topography of the anterior compartment of the female pelvis was studied in serial sections and one anatomical preparation of 30 female fetuses and of six adult females. The pelves of 29 female fetuses were processed according to plastination histology technique. The pelves of the six adult specimens were processed according to sheet plastination technique. In addition, the anatomical findings were compared with MR images of 41 adult female volunteers.ResultsThe ventro‐lateral aspect of the urethra remains free of fixating ligaments throughout its pelvic course. Ventro‐laterally the urethra is enclosed by the ventral parts of the levator ani, its fasciae and a ventral urethral connective tissue bridge connecting both sides. Dorsally, the urethra is intimately connected to the wall of the vagina.ConclusionsThe female urethra has no direct ligamentous fixation to the pubic bone. Urethral continence after pregnancy and childbirth may be explained by a widening of the hiatus of the levator ani or the anterior vaginal wall, resulting in overstretching of the ventral urethral connective tissue bridge or the disruption of the fixation between urethra and vagina. © 2005 Wiley‐Liss, Inc.
Optimal pricing and inventory control policy in periodic‐review systems with fixed ordering cost and lost sales
Authors: Chen Youhua (Frank) , Ray Saibal , Song Yuyue 
Published: December 2005

AbstractThis paper studies a periodic‐review pricing and inventory control problem for a retailer, which faces stochastic price‐sensitive demand, under quite general modeling assumptions. Any unsatisfied demand is lost, and any leftover inventory at the end of the finite selling horizon has a salvage value. The cost component for the retailer includes holding, shortage, and both variable and fixed ordering costs. The retailer's objective is to maximize its discounted expected profit over the selling horizon by dynamically deciding on the optimal pricing and replenishment policy for each period. We show that, under a mild assumption on the additive demand function, at the beginning of each period an (s,S) policy is optimal for replenishment, and the value of the optimal price depends on the inventory level after the replenishment decision has been done. Our numerical study also suggests that for a sufficiently long selling horizon, the optimal policy is almost stationary. Furthermore, the fixed ordering cost (K) plays a significant role in our modeling framework. Specifically, any increase in K results in lower s and higher S. On the other hand, the profit impact of dynamically changing the retail price, contrasted with a single fixed price throughout the selling horizon, also increases with K. We demonstrate that using the optimal policy values from a model with backordering of unmet demands as approximations in our model might result in significant profit penalty. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2006
Upgrading arcs to minimize the maximum travel time in a network
Authors: Campbell Ann Melissa , Lowe Timothy J. , Zhang Li 
Published: December 2005

AbstractIn transportation and telecommunication systems, the performance of the underlying network can often be improved by upgrading some of the arcs in the network. If an arc is upgraded, the travel time along this arc is reduced by a discount factor α, 0 ≤ α < 1. With respect to different minimax network objectives, we define a series of problems that involve finding the best q arcs in a network to upgrade. We show that these problems are NP‐hard on general graphs, but polynomially solvable on trees. Finally, we compare three heuristic solution approaches for complete graphs based on these polynomial results and find one to far outperform the others. © 2006 Wiley Periodicals, Inc. NETWORKS, Vol. 47(2), 72–80 2006