bluuebunny/crossref_metadata_2025_split huggingface dataset:
Energy costs constrain the evolution of gene expression
Authors: Wagner Andreas 
Published: February 2007

AbstractChanges in gene expression affect the energy budget of a cell. A previous contribution estimated the energetic cost of yeast mRNA and protein expression from very limited information on protein half‐lives. Using recently published genome‐scale measurements of protein half‐lives, I here confirm that even small increases in gene expression are opposed by natural selection. In small organisms with large effective population sizes, the evolution of transcription and translation rates are thus not evolutionarily neutral processes. J. Exp. Zool. (Mol. Dev. Evol.) 308B:322–324, 2007. © 2007 Wiley‐Liss, Inc.
Plastic‐embedded semithin cross‐sections as a tool for high‐resolution immunofluorescence analysis of the neuromuscular junction molecules: Specific cellular location of protease‐activated receptor‐1
Authors: Lanuza Maria A. , Besalduch Núria , Garcia Neus , Sabaté Mar , Santafé Manel M. , Tomàs Josep 
Published: February 2007

AbstractIn the neuromuscular junction (NMJ), three cellular elements (nerve ending, postsynaptic muscle component, and teloglial Schwann cell) are closely juxtaposed and functionally interdependent. It is important to determine the precise location of the relevant molecules involved in structural stability and neurotransmission at the three cellular components of this synapse in order to understand the molecular mechanisms underlying NMJ formation, maintenance, and functionality. In this paper, we show that plastic‐embedded 0.5‐μm semithin cross‐sections from whole‐mount multiple‐immunofluorescence‐stained muscles provide a simple and sensitive high‐resolution procedure for analyzing the cellular and subcellular distribution of molecules at the NMJ. We have used this procedure to resolve the location of protease‐activated receptor 1 (PAR‐1). Previously, by immunohistochemistry we had detected PAR‐1 in muscle fibers concentrated in the synaptic area but could not determine whether PAR‐1 is expressed only in the muscle fiber at the NMJ. Our present results demonstrate that PAR‐1 is concentrated in the postsynaptic region but not in the presynaptic terminal and that the labelling pattern for PAR‐1 overlapped with Schwann cell staining. © 2007 Wiley‐Liss, Inc.
Effect of body temperature on chondroitinase ABC's ability to cleave chondroitin sulfate glycosaminoglycans
Authors: Tester Nicole J. , Plaas Anna H. , Howland Dena R. 
Published: February 2007

AbstractChondroitinase ABC (Ch'ase ABC) is a bacterial lyase that degrades chondroitin sulfate (CS), dermatan sulfate, and hyaluronan glycosaminoglycans (GAGs). This enzyme has received significant attention as a potential therapy for promoting central nervous system and peripheral nervous system repair based on its degradation of CS GAGs. Determination of the stability of Ch'ase ABC activity at temperatures equivalent to normal (37°C) and elevated (39°C) body temperatures is important for optimizing its clinical usage. We report here data obtained from examining enzymatic activity at these temperatures across nine lots of commercially available protease‐free Ch'ase ABC. CS GAG degrading activity was assayed by using 1) immunohistochemical detection of unsaturated disaccharide stubs generated by digestion of proteoglycans in tissue sections and 2) fluorophore‐assisted carbohydrate electrophoresis (FACE) and/or high‐performance liquid chromatography (HPLC) to separate and quantify unsaturated disaccharide digestion products. Our results indicate that there is a significant effect of lot and time on enzymatic thermostability. Average enzymatic activity is significantly decreased at 1 and 3 days at 39°C and 37°C, respectively. Furthermore, the average activity seen after 1 day was significantly different between the two temperatures. Addition of bovine serum albumin as a stabilizer significantly preserved enzymatic activity at 1 day, but not 3 days, at 39°C. These results show that the CS GAG degrading activity of Ch'ase ABC is significantly decreased with incubation at body temperature over time and that all lots do not show equal thermostability. These findings are important for the design and interpretation of experimental and potential clinical studies involving Ch'ase ABC. © 2007 Wiley‐Liss, Inc.
Pretreatment with low nitric oxide protects osteoblasts from high nitric oxide‐induced apoptotic insults through regulation of c‐Jun N‐terminal kinase/c‐Jun‐mediated Bcl‐2 gene expression and protein translocation
Authors: Tai Yu‐Ting , Cherng Yih‐Giun , Chang Chia‐Chen , Hwang Yi‐Ping , Chen Jui‐Tai , Chen Ruei‐Ming 
Published: February 2007

AbstractNitric oxide (NO) can regulate osteoblast activity. In this study, we evaluated the effects of pretreatment with a low concentration of NO on osteoblast injuries induced by a high level of NO and its possible molecular mechanisms. Exposure of osteoblasts to 0.3 mM sodium nitroprusside (SNP), an NO donor, slightly increased cellular NO levels without affecting cell viability. SNP at 2 mM greatly increased the levels of cellular NO and reactive oxygen species, and induced osteoblast death. Thus, osteoblasts were treated with 0.3 and 2 mM SNP as the sources of low and high NO, respectively. Exposure of osteoblasts to high NO decreased alkaline phosphatase (ALP) activity and cell viability, and induced cell apoptosis. With low‐NO pretreatment, the high NO‐induced cell insults were significantly ameliorated. When the culture medium was totally replaced after pretreatment with low NO, the protective effects obviously decreased. Administration of high NO significantly decreased c‐Jun N‐terminal kinase (JNK) phosphorylation and nuclear c‐Jun levels. Meanwhile, pretreatment with low NO significantly alleviated the high NO‐induced reduction in activation of JNK and c‐Jun. Sequentially, high NO inhibited Bcl‐2 mRNA and protein synthesis. After pretreatment with low NO, the high NO‐induced inhibition of the production of Bcl‐2 mRNA and protein significantly decreased. Imaging analysis from confocal microscopy further revealed that high NO decreased translocation of the Bcl‐2 protein from the cytoplasm to mitochondria. However, pretreatment with low NO significantly ameliorated the high NO‐induced suppression of Bcl‐2′s translocation. Exposure of human osteoblasts to high NO significantly decreased ALP activity and cell viability, and induced cell apoptosis. Pretreatment with low NO significantly lowered the high NO‐induced alterations in ALP activity, cell viability, and cell apoptosis. This study shows that pretreatment with low NO can protect osteoblasts from high NO‐induced cell insults via JNK/c‐Jun‐mediated regulation of Bcl‐2 gene expression and protein translocation. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:625–635, 2007
Guidewire assisted cephalic vein cutdown for insertion of totally implantable access ports
Authors: Chang H.M. , Hsieh H.F. , Hsu S.D. , Liao G.S. , Lin C.H. , Hsieh C.B. , Yu J.C. 
Published: February 2007

AbstractBackgroundTotally implantable access ports (TIAP) placed by the cephalic vein cutdown technique have high failure rates.MethodsWe describe a guidewire assisted technique of the cephalic vein cutdown for TIAP placement that can be easily introduced catheter when difficulties in insertion of the catheter. The key point of the presented technique is the use of J guidewire to go beyond the stenosis and advancement of catheter through the guidewire into the superior vena cava.ResultsWe used this technique for introducing the catheter in six patients without failure or complication.ConclusionThe presented technique is easy and simple. It can be used where there are difficulties in insertion of the catheter by cephalic vein cutdown method. J. Surg. Oncol. 2007;95:156–157. © 2007 Wiley‐Liss, Inc.
Was ist neu?
Authors: Kock Holger , Thoß Andreas 
Published: February 2007

AbstractLiebe Leserin, lieber Leser,was ist neu? – Genau diese Frage stand beim Zusammenstellen der Inhalte fürs neue Laser Technik Journal im Mittelpunkt. Denn wir wollen der Laserbranche nicht nur einfach eine neue Zeitschrift präsentieren, sondern vielmehr auch inhaltlich mit Neuem überzeugen. Was für uns neu ist? Lesen Sie selbst!Neu ist, … was die Zukunft bringt.Arnold Mayer analysiert für Sie den Lasermarkt in der Materialbearbeitung und sieht bis zum Jahr 2010 gute Wachstumsperspektiven – mit jährlichen Zuwachsraten im zweistelligen Bereich! Mehr dazu auf Seite 9.Neu ist, … was Entscheider denken.Menschen sind die treibende Kraft. Lesen Sie ab Seite 13, was Dirk Basting, der ehemalige Vorstandsvorsitzende von Lambda Physik, zu neuen Märkten und neuen Projekten zu sagen hat.Neu ist, … was neu gesehen wird.Das Laser Technik Journal beleuchtet Schwerpunktthemen aus verschiedenen Blickwinkeln. Das aktuelle Spezial “Lasermaterialbearbeitung” befasst sich mit Strahlquellen und Anwendungen im industriellen Einsatz – mehr dazu ab Seite 40.Neu ist, … was Bewährtes ablöst.In engen Märkten wächst die Bedeutung von gutem Qualitätsmanagement. Wie wichtig optimierte Prozesse für effiziente Abläufe sind, lesen Sie auf Seite 35.Neu ist, … was man noch nicht weiß.Aktuelle Produkte, Nachrichten zu Firmen und Personen sowie Veranstaltungstipps halten Sie auf dem Laufenden.Viel Spaß beim Lesen wünscht Ihnen die Redaktion
Laser in der Materialbearbeitung – Eine Marktübersicht
Authors: Mayer Arnold 
Published: February 2007

AbstractSeit dem Spitzenjahr 2000 ist die Nachfrage für Lasersysteme zur Materialbearbeitung rückläufig. Prognosen für die nächsten Jahre setzen nicht nur auf eine konjunkturelle Erholung, sondern vor allem auf eine stärkere Marktdurchdringung und neue Anwendungen der Lasertechnologie. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Selective Enzymatic Grafting by Steric Control
Authors: Duxbury Christopher J. , Cummins David , Heise Andreas 
Published: February 2007

AbstractEnzymatic grafting of caprolactone was carried out from poly[styrene‐co‐(4‐vinylbenzyl alcohol)] containing 10% hydroxyl functional monomer and compared with the grafting of vinyl acetate. A molecular weight increase due to the grafting of polycaprolactone was observed by size exclusion chromatography. Closer investigation of the grafting density by 1H NMR revealed an upper limit to the amount of grafting of about 50–60% of the pendant hydroxyl groups leaving unreacted hydroxyl groups on the polymer backbone available for subsequent reactions. The higher grafting density (95%) obtained with vinyl acetate suggests that this is not due to limited accessibility of the backbone but sterical constrains. Moreover, the grafting action of polycaprolactone seems to be a combination of grafting from by monomer initiation and grafting onto by transesterification of polycaprolactone.magnified image
Synthesis of Ferrocene‐Branched Chitosan Derivatives: Redox Polysaccharides and their Application to Reagentless Enzyme‐Based Biosensors
Authors: Yang Weiwei , Zhou Hong , Sun Changqing 
Published: February 2007

AbstractFerrocene‐branched chitosan derivatives (CHIT‐Fc) are synthesized by reductive N‐alkylation of chitosan with ferrocenecarboxaldehyde. The structures of the products are determined by 1H NMR and FT‐IR spectra. CHIT‐Fc is used as a functionalized matrix to immobilize GOD on glassy carbon electrodes. Ferrocenyls in CHIT‐Fc exhibit an excellent redox activity and establish efficient electrical communication between GOD and the electrodes for the oxidation of glucose. The development of a reagentless glucose biosensor is described.magnified image
Fatty acids in tea shoots (Camellia sinensis (L.) O. Kuntze) and their effects on the growth of retinal RF/6A endothelial cell lines
Authors: Shen Sheng‐rong , Yu Hai‐ning , Chen Ping , Yin Jun‐jie , Xiong Yao‐kang 
Published: February 2007

AbstractChemo‐protective effects of tea on ocular diseases were recorded in Chinese pharmacopoeia about 2000 years ago by eating tea. In the present study, contents of fatty acids (FAs) in tea shoots were determined by capillary GC; and the growth of RF/6A cells was also investigated by exposure to various representative FAs existing in tea shoots with pathologically relevant concentrations (40–500 μM) by ameliorated MTT assay and flow cytometry. Electron spin resonance (ESR) was used to measure oxygen consumption and investigate the free radical scavenging ability of linoleic acid (LA). Results showed that the most abundant long chain FAs were palmitic, linoleic, and α‐linolenic acid in tea shoots; some RF/6A cells became suspended in culture medium treated by a high dose of both saturated and unsaturated FAs, but no apoptosis was observed. Moreover, it seemed that those FAs with different structure had various effects on the cell proliferation at their relatively low concentrations, LA expressed antioxidant activity in this study, which might be an important mechanism on the protection of eyes.
Theoretical study of the gas‐phase elimination kinetics of several heterocyclic carbamates
Authors: Graterol Mariana , Cordova Tania , Chuchani G. 
Published: February 2007

AbstractThe homogeneous, unimolecular, gas‐phase elimination kinetics of several heterocyclic carbamates was studied at the MP2/6‐31G level of theory under the average experimental conditions for each substrate. The elimination products for these carbamates are the corresponding carbamic acid and isobutylene. The intermediate acids are unstable and decarboxylate at the reaction temperature. Calculated thermodynamic and kinetic parameters are in good agreement with the experimental values, displaying the same reactivity order observed experimentally. An increase in the electron‐withdrawing effect of the substituent on the carbamate nitrogen, increases the elimination rate. Transition state structures are described as six‐membered rings with some departure from planarity. NBO charge analysis reveals strong polarization at the O(ester) δ−Cδ+ bond. Bond indexes and synchronicity parameters are consistent with a concerted polar type of mechanism with O(ester) δ−Cδ+ bond breaking as the most important process. Copyright © 2007 John Wiley & Sons, Ltd.
Substituent effects on ion complexation of para‐tert‐butylcalix[4]arene esters
Authors: Lazzarotto Márcio , Francisco Marjarie Marrie , Nachtigall Francine Furtado , Lazzarotto Marcelo 
Published: February 2007

AbstractPhenoxy‐carboxy‐methoxy‐p‐tert‐butylcalix[4]arene esters were synthesized in order to evaluate the role of electronic parameters on the complexation of alkaline metal cations. Extraction constants of metal picrates to organic phase were determined. Plots of log (KR/KH) against Hammett σ and σ gave good linear correlations. The best correlations with σ were obtained for K+ and Rb+, while the best correlations with σ were obtained for Li+ and Na+. All Hammett plots gave a straight descending line, which is consistent with a dependence of the electronic density on the CO. Treatment of data using the Yukawa–Tsuno equation revealed a variation in the contribution of resonance in the complexation of alkaline metal ions, which is maximum for Na+ and minimum for Rb+. Electronic parameters were calculated for a related acyclic model structure and only the HOMO energy showed a good correlation with log (KR/KH). Copyright © 2007 John Wiley & Sons, Ltd.
Overexpression of cyclooxygenase‐2 in human prostate carcinoma and prostatic intraepithelial neoplasia‐association with increased expression of polo‐like kinase‐1
Authors: Denkert Carsten , Thoma Andrea , Niesporek Silvia , Weichert Wilko , Koch Ines , Noske Aurelia , Schicktanz Hanka , Burkhardt Mick , Jung Klaus , Dietel Manfred , Kristiansen Glen 
Published: February 2007

AbstractBACKGROUNDCyclooxygenases (COX) as well as Polo‐like kinases (PLK) are involved in proliferation and cell cycle regulation and have been suggested for preventive and therapeutic approaches in prostate carcinoma.METHODSIn this study, we studied expression and prognostic impact of COX‐2 in invasive prostate carcinoma, prostatic intraepithelial neoplasia (PIN), atrophic glands, and normal prostatic glands, and investigated the association between COX‐2 and PLK‐1.RESULTSWe observed a positivity for COX‐2 in 72.1% of PIN and in 44.7% of prostate carcinomas with an overexpression of COX‐2 in prostate cancer and PIN compared to benign prostatic tissue (P < 0.0005). Furthermore, we observed a strong correlation between expression of PLK‐1 and COX‐2 (P < 0.0005).CONCLUSIONSTo our knowledge, this is the first report of a correlation between COX‐2 and PLK‐1 in a malignant tumor. COX‐2 and PLK‐1 may be interesting targets for new molecular therapies in prostate cancer. Prostate 67: 361–369, 2007. © 2007 Wiley‐Liss, Inc.
Antiinflammatory effect of topically applied propolis extract in carrageenan‐induced rat hind paw edema
Authors: Naito Yukiko , Yasumuro Misao , Kondou Keiichiro , Ohara Naoki 
Published: February 2007

AbstractThe antiinflammatory effect of an ointment containing propolis extract (3%–7%) was examined using carrageenan‐induced hind paw edema in rats. Treatment with the ointment inhibited the edema moderately, and the inhibition was significant at 5% and 7%. Additionally, the effect of the ointment on chemotaxis of human polymorphonuclear leukocytes (PMNs) was investigated using the agarose plate method. Migration of PMNs toward zymosan‐treated serum was inhibited in the presence of 5% propolis ointment. These results demonstrate that topical application of propolis extract is effective in inhibiting carrageenan‐induced rat hind paw edema, and its inhibitory effect on the chemotaxis of PMNs may also contribute to the antiinflammatory effect. Copyright © 2007 John Wiley & Sons, Ltd.
Meteorology of Nigeria and adjacent territory
Authors: Hamilton R. A. , Archbold J. W. , Douglas C. K. M. 
Published: February 2007

AbstractThis paper deals with the general meteorology of Nigeria and adjacent territory. Part I describes the air masses and prevailing winds and the characteristic weather of four weather zones. Part II describes dust haze and just storms which occur and discusses the question of forecasting the onset and clearance of dust haze. Part III deals with instability phenomena in the form disturbance lines and local thunderstorms; a theory of their mechanism is put forward which agrees well with observed phenomena.
Convection in the atmosphere near the ground
Authors: Sutton O. G. 
Published: February 2007

AbstractThe details of the processes by which heat is transported through the lower atmosphere are, for the most part, still obscure although our knowledge of typical temperature distributions near the ground is now well founded, thanks chiefly to the researches of Johnson (1929), Best (1935), Flower (1936) and Johnson and Heywood (1938). These investigations establish in considerable detail the principal features of the mean temperature field from 2·5 cm. to 87 m., so that the data for the elucidation of the problems of heat transfer are undeniably available, but the complexity of the situation, depending as it must upon the joint effects of radiation, conduction and convection, is such that there is little hope that a comprehensive mathematical theory will be evolved for some time yet.The present paper is an attempt to clarify certain aspects of the problem, and in particular to analyse the general nature of the flux of heat through the lower atmosphere on a clear day in summer. The conclusion is reached that to explain the type of heat flow which prevails in these conditions necessitates the consideration of the nature of the vertical currents due to buoyancy and their effect on the virtual coefficient of conduction, and for this purpose a theoretical treatment is proposed which differs in many ways from those previously advanced.
The dissipation of scattered and broken cloud
Authors: Hewson E. Wendell 
Published: February 2007

AbstractShaw's early work on the dissipation of scattered and broken cloud is outlined and the loss of heat by cloud resulting from terrestrial radiation is indicated. The process of cloud dissipation is described and various criteria are given.The implications of these concepts in evaluating the significance of the slice method for studying cumulus clouds are then considered.A method of calculating the time required for a specified system of scattered and broken cloud to dissipate as a result of radiational cooling is described and the assumptions involved are discussed. The influence of the turbulent transfer of heat and water vapour under various conditions is indicated in a general manner and the effect of the absorption of solar radiation by the cloud is evaluated.Widespread vertical motion of the atmosphere may have a marked influence on cloud dissipation, depending on whether ascent or subsidence of the whole air mass is occurring. A method of calculating the amount of subsidence required to cause a given system of cloud to dissipate is described. For a particular case, the effects of ascent of the air mass and of radiation are combined, and useful criteria thereby obtained.
Equatorial circulations
Authors: Sellick N. P. 
Published: February 2007

AbstractGrimes (1937) made a first essay to treat the passage of air across the equator dynamically. His work has been extended by Crossley (1948). In the present paper a flow pattern is presented which proves not intractable in spherical polar co‐ordinates in the equatorial belt. Frictionless horizontal flow is considered and it is shown that clockwise and counter‐clockwise circulations can exist in equilibrium on the equator. The centre of the pressure field is displaced into the hemisphere for which the circulation is cyclonic and both circulations thus appear as cyclones. It is found that trajectories and contours pass freely across the equator but that the relation between winds and contours is variable.
Empirical formulae for the terminal velocity of water drops falling through the atmosphere
Authors: Best A. C. 
Published: February 2007

AbstractFrom a consideration of experimental measurements of the terminal velocity of water drops and of the drag coefficient of rigid spheres it is suggested that a formula of the type V = A exp bz { 1 – exp [– (d/a)n]} may be used to represent the terminal velocity of water drops which are larger than those to which Stokes's law is applicable and which are falling through a standard atmosphere. If V (the terminal velocity) is measured in cm/sec, z (the height) in km and d (the drop diameter) in mm the values of the constants are as follows:— I.C.A.N. atmosphere Summer tropical atmosphere Range of d mm A b a n A b a n 0.3 to 6.0 932 0.0405 1.77 1.147 958 0.0354 1.77 1.147 0.05 to 0.3 191 0.0290 0.316 1.754 188 0.0256 0.304 1.819 If the drops have diameter less than 0.05 mm, Stokes's law is applicable and V = A d2 exp bz where A is 3040 and 2840 in the I.C.A.N. and S.T. atmospheres respectively and b has the values 0.0191 and 0.0172 in these two atmospheres.
The ratio between observed velocities of the wind at 50 feet and 2000 feet over the North Atlantic Ocean
Authors: Gordon A. H. 
Published: February 2007

AbstractThe ratio of the wind at 50 ft to the wind at 2000 ft has been calculated for a number of cases from ocean weather ship observations over the North Atlantic and mean values classified according to the lapse rate and the velocity of the wind at 2000 ft. Curves have been drawn showing the variation of the ratio v50/v2000 with lapse rate and v2000 respectively.