bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determining particle density distribution of expanded bed adsorbents
Authors: Hassan Sally , Titchener‐Hooker Nigel , Willoughby Nik 
Published: October 2005

AbstractThis study presents an experimental approach to measure the density distribution of expanded bed adsorption (EBA) matrices. We report on the use of a series of solutions of caesium trifluoroacetate (CsTFA) of varying density spun in a laboratory centrifuge so as to separate representative matrix samples on the basis of bead density. Mass data was used to plot a decumulative density distribution for the matrix. By performing laser light scattering‐based measurements on the same samples of matrix the variation in particle size with density was determined. Particle settling velocity distributions were then calculated using these data and compared with a settling velocity distribution calculated on the basis of an assumed constant bead density. The study demonstrates a reliable and simple method for the characterisation of matrix density distribution. For the case of the Streamline matrices tested the particle size distribution is constant with varying bead density. Bead densities varied from 1.5 to 2.1 g/cm3 in the CsTFA solutions. These were then adjusted using bead porosity to give a density range of 1.11–1.33 g/cm3 in aqueous buffer (assumed 1.0 g/cm3) The differences in resultant settling velocity distributions when based upon measured density distribution than when based upon an assumed mean density value were shown to be insignificant. This result confirms experimentally that an assumption of a single constant mean density for EBA particles is acceptable for hydrodynamic modelling and performance prediction purposes. © 2005 Wiley Periodicals, inc.
Optimization of DsRed production in Escherichia coli: Effect of ribosome binding site sequestration on translation efficiency
Authors: Pfleger Brian F. , Fawzi Nicolas J. , Keasling Jay D. 
Published: October 2005

AbstractDsRed‐Express, a popular reporter protein, cannot be expressed in Escherichia coli using a consensus ribosome binding site (RBS) potentially due to basepairing in the RBS that inhibits translation initiation. Saturation mutagenesis was used to probe for a gene sequence that minimized basepairing in the RBS while maintaining the same spectral properties and maturation characteristics as DsRed‐Express. The new DsRed, designated here as RFPEC for E. coli optimized red fluorescent protein, fluoresces 2.5 times greater than DsRed‐Express when expressed from the same vector. © 2005 Wiley Periodicals, inc.
Comparison of melatonin, vitamin E and L‐carnitine in the treatment of neuro‐ and hepatotoxicity induced by thioacetamide
Authors: Túnez Isaac , Muñoz M. Carmen , Medina Francisco J. , Salcedo Manuel , Feijóo Montserrat , Montilla Pedro 
Published: October 2005

AbstractThis study was designed to evaluate and compare the effect of melatonin, vitamin E and L‐carnitine on brain and liver oxidative stress and liver damage. Oxidative stress and hepatic failure were produced by a single dose of thioacetamide (TAA) (150 mg kg−1) in Wistar rats. A dose of either melatonin (3 mg kg−1) vitamin E (20 mg kg−1) or L‐carnitine (100 mg kg−1) was used. Blood samples were taken from the neck vasculature in order to determine ammonium, blood urea nitrogen (BUN) and liver enzymes. Lipid peroxidation products, glutathione (GSH) content and antioxidative enzymes were determined in cerebral and hepatic homogenates. The results showed a decrease in BUN and in the antioxidant enzymes activities and GSH in the brain and liver. Likewise, TAA induced significant enhancement of lipid peroxidation products levels in both liver and brain, as well as in ammonia values. Melatonin, vitamin E and L‐carnitine, although melatonin more significantly, decreased the intensity of the changes produced by the administration of TAA alone. Furthermore melatonin combined with TAA, decreased the ammonia levels and increased the BUN values compared with TAA animals. Also it was more effective than vitamin E or L‐carnitine in these actions. These data show the protective effect of these agents, especially melatonin, against oxidative stress and hepatic damage present in fulminant hepatic failure. Copyright © 2005 John Wiley & Sons, Ltd.
Ischemic preconditioning preserves proton leakage from mitochondrial membranes but not oxidative phosphorylation during heart reperfusion
Authors: Muscari Claudio , Bonafè Francesca , Gamberini Chiara , Giordano Emanuele , Lenaz Giorgio , Caldarera Claudio Marcello 
Published: October 2005

AbstractThe aim of this study was to evaluate the role of mitochondria in the recovery of cardiac energetics induced by ischaemic preconditioning at reperfusion. Isolated rat hearts were aerobically perfused (control), subjected to global ischaemia and reperfusion (reperfusion), or subjected to 3 brief cycles of ischaemia/reperfusion and then to the protocol of reperfusion (preconditioning). At the end of the perfusion, antimycin A was delivered to the heart for 25 min, to inhibit mitochondrial respiration and stimulate glycolysis. The increased amount of lactate released in the coronary effluent was correlated with the number of viable cells producing this end‐product of glycolysis. Preconditioned hearts released 18% more lactate than reperfused hearts (p < 0.05). This result indicates that preconditioning partially preserved cell viability, as was also evidenced by the MTT assay performed on cardiac biopsies. The difference between antimycin A‐stimulated and basal lactate concentration, representing the contribution of mitochondria to the overall energetics of cardiac tissue, was also 18% more elevated in the preconditioned hearts than in the reperfused hearts (p < 0.01). The study of the respiratory function of mitochondria isolated at the end of perfusion, showed that preconditioning did not improve the oxygen‐dependent production of ATP (state 3 respiration, ADP/O). On the contrary, state 4 respiration, which is related to proton leakage, was 35.0% lower in the preconditioned group than reperfusion group (p < 0.05). Thus, preconditioning ameliorates cardiac energetics by preserving cell death, but without affecting mitochondrial oxidative phosphorylation. Mitochondria can contribute to cell survival by the attenuation of proton leak from inner membrane. Copyright © 2005 John Wiley & Sons, Ltd.
Effects of intraperitoneally administered ubiquinone on the level of total lipid and fatty acids in rat liver
Authors: Çelik Sait , Akarçay Hatice , Yılmaz Ökkeş , Özkaya Ahmet 
Published: October 2005

AbstractThe purpose of the present study was to evaluate the effect of ubiquinone (coenzyme Q‐10) on total lipid and fatty acid composition of liver tissues in rats. Twenty male wistar rats were randomly divided into two groups. The first group was used as a control. The second group received ubiquinone (8 mg/every other day) intraperitoneally. This administration was done for a period of 38 days. Body weight increases in animals fed diets for 38 days were on average 35 g in control group (C), and only 11 g in the ubiquinone group. Total lipid content of liver tissues in the ubiquinone group (UB) decreased significantly (p < 0.0001) compared to the control group (C). The ratio of 22:6 and total ω3 fatty acid in the UB increased (p < 0.01) compared to C. While the level of oleic acid (18:1), palmitoleic acid (16:1) and total monounsaturated fatty acid (MUFA) in UB significantly decreased (p < 0.01, p < 0.001, p < 0.001, respectively), the level of stearic acid (18:0) in liver tissue increased (p < 0.05) in the same group when compared to C. Stearoyl‐CoA desaturase (SCD) is the rate‐limiting enzyme catalyzing the synthesis of monounsaturated fatty acid mainly oleate (18:1). We speculate that ubiquinone inhibits SCD activity. SCD is an important metabolic control point in body weight regulation. Our results indicate that ubiquinone supplementation may have an inhibitory effect on obesity and it seems that the level of 22:6 in liver increased due to ubiquinone. Copyright © 2005 John Wiley & Sons, Ltd.
Binding of Helix‐Threading Peptides to E. coli 16S Ribosomal RNA and Inhibition of the S15–16S Complex
Authors: Gooch Barry D. , Krishnamurthy Malathy , Shadid Mohammad , Beal Peter A. 
Published: October 2005

AbstractHelix‐threading peptides (HTPs) constitute a new class of small molecules that bind selectively to duplex RNA structures adjacent to helix defects and project peptide functionality into the dissimilar duplex grooves. To further explore and develop the capabilities of the HTP design for binding RNA selectively, we identified helix 22 of the prokaryotic ribosomal RNA 16S as a target. This helix is a component of the binding site for the ribosomal protein S15. In addition, the S15–16S RNA interaction is important for the ordered assembly of the bacterial ribosome. Here we present the synthesis and characterization of helix‐threading peptides that bind selectively to helix 22 of E. coli 16S RNA. These compounds bind helix 22 by threading intercalation placing the N termini in the minor groove and the C termini in the major groove. Binding is dependent on the presence of a highly conserved purine‐rich internal loop in the RNA, whereas removal of the loop minimally affects binding of the classical intercalators ethidium bromide and methidiumpropyl–EDTA⋅Fe (MPE⋅Fe). Moreover, binding selectivity translates into selective inhibition of formation of the S15–16S complex.
Unidirectional Threading Synthesis of Isomer‐Free [2]Rotaxanes
Authors: Wang Qiao‐Chun , Ma Xiang , Qu Da‐Hui , Tian He 
Published: October 2005

AbstractThe threading of an α‐cyclodextrin (α‐CyD) by an unsymmetrical dumbbell generally results in two isomeric [2]rotaxanes differing in the orientation of the α‐CyD. In this work, two methods have been developed for the unidirectionally threading an α‐CyD to obtain isomer‐free [2]rotaxanes. These methods use the Suzuki coupling of a boronic acid derivative and a halide in aqueous alkaline solution. The conformations of the two unidirectional [2]rotaxanes‐R3 and R4 were determined by 2D 1H ROESY NMR spectra. The optical spectral studies revealed that each of the two [2]rotaxanes can proceed with E/Z photoisomerization and shuttling motions of the α‐CyD ring on the thread under alternating irradiation at 330 and 275 nm, accompanied by fluorescence intensity changes at 530 nm. The induced circular dichroism (ICD) spectra of another two analogous [2]rotaxanes R1 and R2 were also studied. Distinctive ICD signal changes resulting from the photoisomerization with respect to the movements of α‐CyD were detected. This demonstrates that, besides the fluorescence, ICD signal is another way to identify the shuttling motions of α‐CyD in these [2]rotaxanes.
Synthesis of Heterobimetallic RuMn Complexes and the Coupling Reactions of Epoxides with Carbon Dioxide Catalyzed by these Complexes
Authors: Man Man Lok , Lam King Chung , Sit Wing Nga , Ng Siu Man , Zhou Zhongyuan , Lin Zhenyang , Lau Chak Po 
Published: October 2005

AbstractThe heterobimetallic complexes [(η5‐C5H5)Ru(CO)(μ‐dppm)Mn(CO)4] and [(η5‐C5Me5)Ru(μ‐dppm)(μ‐CO)2Mn(CO)3] (dppm= bis‐diphenylphosphinomethane) have been prepared by reacting the hydridic complexes [(η5‐C5H5)Ru(dppm)H] and [(η5‐C5Me5)Ru(dppm)H], respectively, with the protonic [HMn(CO)5] complex. The bimetallic complexes can also be synthesized through metathetical reactions between [(η5‐C5R5)Ru(dppm)Cl] (R=H or Me) and Li+[Mn(CO)5]−. Although the complexes fail to catalyze the hydrogenation of CO2 to formic acid, they catalyze the coupling reactions of epoxides with carbon dioxide to yield cyclic carbonates. Two possible reaction pathways for the coupling reactions have been proposed. Both routes begin with heterolytic cleavage of the RuMn bond and coordination of an epoxide molecule to the Lewis acidic ruthenium center. In Route I, the Lewis basic manganese center activates the CO2 by forming the metallocarboxylate anion which then ring‐opens the epoxide; subsequent ring‐closure gives the cyclic carbonate. In Route II, the nucleophilic manganese center ring‐opens the ruthenium‐attached epoxide to afford an alkoxide intermediate; CO2 insertion into the RuO bond followed by ring‐closure yields the product. Density functional calculations at the B3LYP level of theory were carried out to understand the structural and energetic aspects of the two possible reaction pathways. The results of the calculations indicate that Route II is favored over Route I.
Medication safety in the ambulatory chemotherapy setting
Authors: Gandhi Tejal K. , Bartel Sylvia B. , Shulman Lawrence N. , Verrier Deborah , Burdick Elisabeth , Cleary Angela , Rothschild Jeffrey M. , Leape Lucian L. , Bates David W. 
Published: October 2005

AbstractBACKGROUNDLittle is known concerning the safety of the outpatient chemotherapy process. In the current study, the authors sought to identify medication error and potential adverse drug event (ADE) rates in the outpatient chemotherapy setting.METHODSA prospective cohort study of two adult and one pediatric outpatient chemotherapy infusion units at one cancer institute was performed, involving the review of orders for patients receiving medication and/or chemotherapy and chart reviews. The adult infusion units used a computerized order entry writing system, whereas the pediatric infusion unit used handwritten orders. Data were collected between March and December 2000.RESULTSThe authors reviewed 10,112 medication orders (8008 adult unit orders and 2104 pediatric unit orders) from 1606 patients (1380 adults and 226 pediatric patients). The medication error rate was 3% (306 of 10,112 orders). Of these errors, 82% occurring in adults (203 of 249 orders) had the potential for harm and were potential ADEs, compared with 60% of orders occurring in pediatric patients (34 of 57 orders). Among these, approximately one‐third were potentially serious. Pharmacists and nurses intercepted 45% of potential ADEs before they reached the patient. Several changes were implemented in the adult and pediatric settings as a result of these findings.CONCLUSIONSIn the current study, the authors found an ambulatory medication error rate of 3%, including 2% of orders with the potential to cause harm. Although these rates are relatively low, there is clearly the potential for serious patient harm. The current study identified strategies for prevention. Cancer 2005. © 2005 American Cancer Society.
Reducing adverse drug events in the outpatient chemotherapy setting
Authors: Nebeker Jonathan R. , Bennett Charles L. 
Published: October 2005

Cancer agents have the potential for severe, and occasionally fatal, adverse drug events. Many receive accelerated approval for use after small clinical trials, with adverse drug events being identified after additional experience in the postmarketing clinical setting. Moreover, chemotherapy risks may be especially high in tertiary care settings where patients are frequently subject to complex treatment protocols with high dosages, novel agents, or novel combinations of agents. Recommendations from the study on medication errors by Gandhi et al. contribute to international efforts to prevent adverse drug reactions and improve their early recognition and treatment.See also pages 2477–83.
Reciprocal expression of lin‐41 and the microRNAs let‐7 and mir‐125 during mouse embryogenesis
Authors: Schulman Betsy R. Maller , Esquela‐Kerscher Aurora , Slack Frank J. 
Published: October 2005

AbstractIn C. elegans, heterochronic genes control the timing of cell fate determination during development. Two heterochronic genes, let‐7 and lin‐4, encode microRNAs (miRNAs) that down‐regulate a third heterochronic gene lin‐41 by binding to complementary sites in its 3′UTR. let‐7 and lin‐4 are conserved in mammals. Here we report the cloning and sequencing of mammalian lin‐41 orthologs. We find that mouse and human lin‐41 genes contain predicted conserved complementary sites for let‐7 and the lin‐4 ortholog, mir‐125, in their 3′UTRs. Mouse lin‐41 (Mlin‐41) is temporally expressed in developing mouse embryos, most dramatically in the limb buds. Mlin‐41 is down‐regulated during mid‐embryogenesis at the time when mouse let‐7c and mir‐125 RNA levels are up‐regulated. Our results suggest that mammalian lin‐41 is temporally regulated by miRNAs in order to direct key developmental events such as limb formation. Developmental Dynamics 234:1046–1054, 2005. © 2005 Wiley‐Liss, Inc.
Altered primary CD8+ T cell response to a modified virus Ankara(MVA)‐vectored vaccine in the absence of CD4+ T cell help
Authors: Estcourt Marie J. , McMichael Andrew J. , Hanke Tomáš 
Published: October 2005

AbstractT cell receptor‐transgenic F5 mice were used to assess primary CD8+ T cell responses to a modified virus Ankara (MVA)‐vectored vaccine in the absence of CD4+ T cell help. Naive, CD8‐enriched, CFSE‐labelled F5 cells were transferred into normal or CD4+ cell‐depleted mice and the mice were vaccinated with MVA.HIVA‐NP. At different time points during the primary response, F5 cells were re‐isolated and analysed on divisional basis for a number of parameters. We demonstrated that the primary CD8+ T cell response in the absence of CD4+ T cell help differed from that in normal CD4+ cell‐undepleted mice. While in the absence of CD4+ T cell help, the initial migratory progress from the local response to a systemic one was not grossly affected, the proportion of dying F5 cells during the expansion phase was markedly increased and resulted in an overall smaller expansion and significantly decreased frequency of CD8+ T cell memory after contraction. T cells primed without help displayed accelerated proliferation and activation, while expression of interferon‐γ remained similar. These phenomena were observed in the lymph nodes draining the MVA.HIVA‐NP immunization site and were similar, but delayed by 2–3 days in spleen and non‐draining lymph nodes.
Neural correlates of anosognosia for cognitive impairment in Alzheimer's disease
Authors: Salmon Eric , Perani Daniela , Herholz Karl , Marique Patricia , Kalbe Elke , Holthoff Vjera , Delbeuck Xavier , Beuthien‐Baumann Bettina , Pelati Oriana , Lespagnard Solange , Collette Fabienne , Garraux Gaëtan 
Published: October 2005

AbstractWe explored the neural substrate of anosognosia for cognitive impairment in Alzheimer's disease (AD). Two hundred nine patients with mild to moderate dementia and their caregivers assessed patients' cognitive impairment by answering a structured questionnaire. Subjects rated 13 cognitive domains as not impaired or associated with mild, moderate, severe, or very severe difficulties, and a sum score was calculated. Two measures of anosognosia were derived. A patient's self assessment, unconfounded by objective measurements of cognitive deficits such as dementia severity and episodic memory impairment, provided an estimate of impaired self‐evaluative judgment about cognition in AD. Impaired self‐evaluation was related to a decrease in brain metabolism measured with 18F‐2‐fluoro‐2‐deoxy‐D‐glucose positron emission tomography (FDG‐PET) in orbital prefrontal cortex and in medial temporal structures. In a cognitive model of anosognosia, medial temporal dysfunction might impair a comparison mechanism between current information on cognition and personal knowledge. Hypoactivity in orbitofrontal cortex may not allow AD patients to update the qualitative judgment associated with their impaired cognitive abilities. Caregivers perceived greater cognitive impairments than patients did. The discrepancy score between caregiver's and patient's evaluations, an other measure of anosognosia, was negatively related to metabolic activity located in the temporoparietal junction, consistent with an impairment of self‐referential processes and perspective taking in AD. Hum Brain Mapp, 2005. © 2005 Wiley‐Liss, Inc.
Optimization of expression ofdhaT gene encoding 1,3‐propanediol oxidoreductase fromKlebsiella pneumoniaeinEscherichia coliusing the methods of uniform design and regression analysis
Authors: Cao Yang , Xia Qirong , Fang Baishan 
Published: October 2005

AbstractThis paper is concerned with the optimization of expression conditions of 1,3‐propanediol oxidoreductase (PDOR) using the uniform design (UD) method and regression analysis. The concentration of the inducer isopropyl‐β‐D‐thiogalactopyranoside (IPTG), the induction temperature and the induction time, which were identified as three crucial factors, were optimized in 50 mL cultivation tubes containing 5 mL LB culture. The optimal expression conditions for enhanced PDOR activity were found to be an IPTG concentration of 0.1 mmol l−1, an induction temperature of 21.2 °C and an induction time of 5 h. Subsequent experimental trials confirmed the validity of the model. These optimal expression conditions in the cultivation tube culture led to a PDOR activity of 9.25 U mL−1, which was considerably higher than those obtained in the optimizing experimental trials. Copyright © 2005 Society of Chemical Industry
Chemical characterization and liberation of pentose sugars from brewer's spent grain
Authors: Mussatto Solange I , Roberto Inês C 
Published: October 2005

AbstractThe chemical composition of brewer's spent grain (BSG), generated from a process using 100% malted barley, was investigated. BSG is mainly composed of (g kg−1) hemicellulose (284), lignin (278), cellulose (168) and protein (152.5), but it also contains extractives and ashes in smaller proportions. Minerals in BSG include calcium, sodium, potassium, magnesium, aluminum, iron, barium, strontium, manganese, copper, zinc, phosphorus, sulfur, chromium and silicon. In order to find alternative uses for BSG, this by‐product was subjected to acid hydrolysis process to recover the hemicellulosic sugars, which have a large number of industrial applications. The process was carried out under different conditions of liquid‐to‐solid ratio and acid concentration to evaluate the influence of these two variables on BSG hemicellulose hydrolysis. Under all the hydrolysis conditions evaluated, arabinose was recovered with higher efficiency than xylose. Under the best evaluated reaction conditions (liquid‐to‐solid ratio of 10 g g−1 and 120 mg H2SO4 g−1 dry matter) 76.2% of the hemicellulose was hydrolyzed and the xylose and arabinose sugars were recovered with 67 and 97.8% efficiency, respectively. Copyright © 2005 Society of Chemical Industry
A correlation for dispersed phase axial mixing coefficients in rotating disc contactors
Authors: Murugesan Thanapalan , Regupathi Iyyasami 
Published: October 2005

AbstractA correlation for the estimation of dispersed phase axial mixing coefficients in terms of all the operating and fundamental variables was established. The proposed correlations are found to be a good representation of the present data (260 data points) obtained using four liquid‐liquid systems from two different sources. Copyright © 2005 Society of Chemical Industry
The effect of substrate concentrations on the production of biodiesel by lipase‐catalysed transesterification of vegetable oils
Authors: Al‐Zuhair Sulaiman 
Published: October 2005

AbstractAll the kinetic studies, found in the literature, on the production of biodiesel (fatty acids methyl esters) considered the esterifications of free fatty acids rather than the transesterification of the vegetable oil itself. The main industrial interest, however, is for the production of biodiesel with the triglyceride (oil) being the substrate. A mathematical model taking into account the mechanism of the methanolysis reaction starting from the vegetable oil as substrate, rather than the free fatty acids, has been developed. From the proposed model equation, the regions where the effect of alcohol inhibition fades, at different substrate concentrations, were identified. The proposed model equation can be used to predict the rate of methanolysis of vegetable oils in a batch or a continuous reactor and to determine the optimal conditions for biodiesel production. Copyright © 2005 Society of Chemical Industry