bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapid strain improvement through optimized evolution in the cytostat
Authors: Gilbert Alan , Sangurdekar Dipen P. , Srienc Friedrich 
Published: January 2009

AbstractAcetate is present in lignocellulosic hydrolysates at growth inhibiting concentrations. Industrial processes based on such feedstock require strains that are tolerant of this and other inhibitors present. We investigated the effect of acetate on Saccharomyces cerevisiae and show that elevated acetate concentrations result in a decreased specific growth rate, an accumulation of cells in the G1 phase of the cell cycle, and an increased cell size. With the cytostat cultivation technology under previously derived optimal operating conditions, several acetate resistant mutants were enriched and isolated in the shortest possible time. In each case, the isolation time was less than 5 days. The independently isolated mutant strains have increased specific growth rates under conditions of high acetate concentrations, high ethanol concentrations, and high temperature. In the presence of high acetate concentrations, the isolated mutants produce ethanol at higher rates and titers than the parental strain and a commercial ethanol producing strain that has been analyzed for comparison. Whole genome microarray analysis revealed gene amplifications in each mutant. In one case, the LPP1 gene, coding for lipid phosphate phosphatase, was amplified. Two mutants contained amplified ENA1, ENA2, and ENA5 genes, which code for P‐type ATPase sodium pumps. LPP1 was overexpressed on a plasmid, and the growth data at elevated acetate concentrations suggest that LPP1 likely contributes to the phenotype of acetate tolerance. A diploid cross of the two mutants with the amplified ENA genes grew faster than either individual haploid parent strain when 20 g/L acetate was supplemented to the medium, which suggests that these genes contribute to acetate tolerance in a gene dosage dependent manner. Biotechnol. Bioeng. 2009;103: 500–512. © 2009 Wiley Periodicals, Inc.
Analysis of cell locomotion on ligand gradient substrates
Authors: Sarvestani Alireza S. , Jabbari Esmaiel 
Published: January 2009

AbstractDirectional cell motility plays a key role in many biological processes like morphogenesis, inflammation, wound repair, angiogenesis, immune response, and tumor metastasis. Cells respond to the gradient in surface ligand density by directed locomotion towards the direction of higher ligand density. Theoretical models which address the physical basis underlying the regulatory effect of ligand gradient on cell motility are highly desirable. Predictive models not only contribute to a better understanding of biological processes, but they also provide a quantitative interconnection between cell motility and biophysical properties of the extracellular matrix (ECM) for rational design of biomaterials as scaffolds in tissue engineering. In this work, we consider a one‐dimensional (1D) continuum viscoelastic model to predict the cell velocity in response to linearly increasing density of surface ligands on a substrate. The cell is considered as a 1D linear viscoelastic object with position dependent elasticity due to the variation in actin network density. The cell–substrate interaction is characterized by a frictional force, controlled by the density of ligand–receptor pairs. The generation of contractile stresses is described in terms of kinetic equations for the reactions between actins, myosins, and guanine nucleotide regulatory proteins. The model predictions show a reasonable agreement with experimentally measured cell speeds, considering biologically relevant values for the model parameters. The model predicts a biphasic relationship between cell speed and slope of gradient as well as a maximum limiting speed after a finite migration time. For a given slope of ligand gradient, the onset of the limiting speed appears at longer times for substrates with lower ligand gradients. The model can be applied to the design of biomaterials as scaffolds for guided tissue regeneration as it predicts an optimum range for the slope of ligand gradient. Biotechnol. Bioeng. 2009;103: 424–429. © 2009 Wiley Periodicals, Inc.
Quality monitoring in thyroid surgery using the Shewhart control chart
Authors: Duclos A , Touzet S , Soardo P , Colin C , Peix J L , Lifante J C 
Published: January 2009

Abstract

Background
A control chart can help to interpret and reduce sources of variability in patient safety by continuously monitoring indicators. The aim of this study was to monitor the outcome of thyroid surgery using control charts.

Methods
Patients who had thyroid surgery during 2006–2007 were included in the study. Safety was monitored based on postoperative complications of recurrent laryngeal nerve palsy and hypocalcaemia. Indicators were extracted prospectively from the hospital information system and plotted each month on a P-control chart. Performance of the surgical team was also measured retrospectively for 2004–2005 (baseline period) to compare surgical outcomes before and after control chart implementation. Electromyographic monitoring of recurrent laryngeal nerves was not used, nor was calcium or vitamin D given routinely.

Results
The outcomes of 1114 thyroid procedures were monitored. Although the proportion of patients with recurrent laryngeal nerve palsy was similar for baseline and monitored periods (6·4 and 7·2 per cent respectively), there was a 35·3 per cent decrease in hypocalcaemia after implementation of control charts (P &lt; 0·001). Complications almost doubled during a period when one surgeon was away and operating room renovations took place.

Conclusion
Outcome monitoring in thyroid surgery using control charts is useful for identifying potential issues in patient safety.
Treatment of liver metastases from neuroendocrine tumours in relation to the extent of hepatic disease
Authors: Frilling A , Li J , Malamutmann E , Schmid K-W , Bockisch A , Broelsch C E 
Published: January 2009

Abstract

Background
Hepatic surgery is presumed to improve survival of patients with liver metastases (LM) from neuroendocrine tumours (NET). This study identified LM-specific variables that could be used as additional selection criteria for aggressive treatment.

Methods
A novel classification of LM from NET was established based on their localization and presentation.

Results
From 1992 to 2006, 119 patients underwent staging and treatment of LM. Three growth types of LM were identified radiologically: single metastasis (type I), isolated metastatic bulk accompanied by smaller deposits (type II) and disseminated metastatic spread (type III). The three groups differed significantly in terms of chronological presentation of LM, hormonal symptoms, Ki-67 index, 5-hydroxyindoleacetic acid and chromogranin A levels, lymph node involvement, presence of bone metastases and treatment options. The 3-, 5- and 10-year disease-specific survival rates for the entire cohort were 76·4, 63·9 and 46·5 per cent respectively. There were significant differences in survival between the three groups: 5- and 10-year rates were both 100 per cent for type I, 84 and 75 per cent respectively for type II, and 51 and 29 per cent for type III.

Conclusion
The localization and biological features of LM from NET defines therapeutic management and is predictive of outcome.
Oxidant‐Free Dehydrogenation of Alcohols Heterogeneously Catalyzed by Cooperation of Silver Clusters and Acid–Base Sites on Alumina
Authors: Shimizu Ken‐ichi , Sugino Kenji , Sawabe Kyoichi , Satsuma Atsushi 
Published: January 2009

AbstractTrifunctional green catalysis: In‐depth characterization shows that oxidant‐free selective oxidation of alcohols by silver nanoparticles on γ‐Al2O3, as a new heterogeneous catalyst, proceeds through cooperation of silver, acid, and base sites (see figure).magnified imageA γ‐alumina‐supported silver cluster catalyst—Ag/Al2O3—has been shown to act as an efficient heterogeneous catalyst for oxidant‐free alcohol dehydrogenation to carbonyl compounds at 373 K. The catalyst shows higher activity than conventional heterogeneous catalysts based on platinum group metals (PGMs) and can be recycled. A systematic study on the influence of the particle size and oxidation state of silver species, combined with characterization by Ag K‐edge XAFS (X‐ray absorption fine structure) has established that silver clusters of sizes below 1 nm are responsible for the higher specific rate. The reaction mechanism has been investigated by kinetic studies (Hammett correlation, kinetic isotope effect) and by in situ FTIR (kinetic isotope effect for hydride elimination reaction from surface alkoxide species), and the following mechanism is proposed: 1) reaction between the alcohol and a basic OH group on the alumina to yield alkoxide on alumina and an adsorbed water molecule, 2) CH activation of the alkoxide species by the silver cluster to form a silver hydride species and a carbonyl compound, and 3) H2 desorption promoted by an acid site in the alumina. The proposed mechanism provides fundamental reasons for the higher activities of silver clusters on acid–base bifunctional support (Al2O3) than on basic (MgO and CeO2) and acidic to neutral (SiO2) ones. This example demonstrates that catalysts analogous to those based on of platinum group metals can be designed with use of a less expensive d10 element—silver—through optimization of metal particle size and the acid–base natures of inorganic supports.
Drosophila RSK negatively regulates bouton number at the neuromuscular junction
Authors: Fischer Matthias , Raabe Thomas , Heisenberg Martin , Sendtner Michael 
Published: January 2009

AbstractRibosomal S6 kinases (RSKs) are growth factor‐regulated serine‐threonine kinases participating in the RAS‐ERK signaling pathway. RSKs have been implicated in memory formation in mammals and flies. To characterize the function of RSK at the synapse level, we investigated the effect of mutations in the rsk gene on the neuromuscular junction (NMJ) in Drosophila larvae. Immunostaining revealed transgenic expressed RSK in presynaptic regions. In mutants with a full deletion or an N‐terminal partial deletion of rsk, an increased bouton number was found. Restoring the wild‐type rsk function in the null mutant with a genomic rescue construct reverted the synaptic phenotype, and overexpression of the rsk‐cDNA in motoneurons reduced bouton numbers. Based on previous observations that RSK interacts with the Drosophila ERK homologue Rolled, genetic epistasis experiments were performed with loss‐ and gain‐of‐function mutations in Rolled. These experiments provided evidence that RSK mediates its negative effect on bouton formation at the Drosophila NMJ by inhibition of ERK signaling. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2009
Moisture controls on carbon dioxide dynamics of peat‐Sphagnum monoliths
Authors: Strack M. , Price J. S. 
Published: January 2009

AbstractSphagnum moss is the major peat‐forming vegetation component in boreal peatlands. The relationship between Sphagnum productivity and moss moisture content has been documented; however, the link between moss moisture content and conditions in the underlying peat column is less clear. We conducted a pilot study in which we monitored volumetric moisture content with depth and gravimetric water content of Sphagnum capitula and CO2 exchange for two peat monoliths with intact moss layer dominated by Sphagnum fuscum and S. magellanicum. Measurements were made under drying conditions and rewetting from below and following simulated precipitation events. Capitulum moisture content was related to water table position but varied between species. Both capitulum moisture content and water table position could be used to explain net CO2 exchange and respiration during drying and rewetting from below, although hysteresis was apparent where respiration was lower on rewetting than drying for the same water table position. Precipitation complicated these relationships because small events (<5 mm) rewetted the upper few centimeters of moss resulting in a change in capitulum moisture content equivalent to a rise in water table position of ∼20 cm. This change in capitulum moisture content resulted in substantial shifts in both photosynthesis and respiration rates without affecting water table position or subsurface volumetric water contents as shallow as 5 cm below the surface. While these small events will be difficult to measure in the field, this study suggests they are essential to effectively track or model Sphagnum productivity because they may contribute significantly to seasonal carbon balance. Copyright © 2009 John Wiley & Sons, Ltd.
Linking water sources with foliar nutrient status in upland plant communities in the Everglades National Park, USA
Authors: Saha Amartya K. , Lobo O'Reilly Sternberg Leonel da Silviera , Miralles‐Wilhelm Fernando 
Published: January 2009

AbstractPlant communities within an ecosystem can vary in water source usage and nutrient availabilities, thus permitting community coexistence and diversity. We investigated the differences in water source utilization in two ecologically important upland plant communities: tropical hardwood hammocks and pine rocklands in the predominantly flooded Everglades ecosystem. We then linked these differences with their foliar nutrient levels and photosynthetic performance as measured by δ13C abundance. Based on a comparison of δ18O of plant stem waters with those of potential water sources (nutrient‐poor groundwater and nutrient‐rich water in organic litter referred to as soilwater), we observed that during the wet season hammock plants relied on soilwater while in the dry season they relied on groundwater. A similar seasonal shift was observed in pineland plants, however, groundwater constituted the major part of water uptake throughout the year except for late wet season. Consistent with the nutrient concentration of different water sources used in the two communities, hammocks had a greater annual mean foliar nitrogen and phosphorus concentration at the community level over pinelands as well as a higher leaf area index. High foliar N concentration in hammock plants was associated with eventual stomatal limitation of photosynthesis. Hammock species being intolerant of flooded soils are restricted to water uptake in the shallow unsaturated soil layer in the wet season, yet access the lowered groundwater table in the dry season. This dependence on a relatively narrow annual range of water table levels should be considered in South Florida water management and Everglades restoration. Copyright © 2009 John Wiley & Sons, Ltd.
Catalytic Asymmetric Oxidation of Heteroaromatic Sulfides with tert‐Butyl Hydroperoxide Catalyzed by a Titanium Complex with a New Chiral 1,2‐Diphenylethane‐1,2‐diol Ligand
Authors: Jiang Biao , Zhao Xiao‐Long , Dong Jia‐Jia , Wang Wan‐Jun 
Published: January 2009

AbstractHeteroaromatic sulfoxides, especially 1H‐benzimidazolylpyridinylmethyl sulfoxides, usually used as the blockbuster gastric proton pump inhibitors (PPIs), have been prepared highly enantioselectivily by catalytic asymmetric oxidation of sulfides attached to nitrogen‐containing heterocyles with tert‐butyl hydroperoxide in the presence of a chiral titanium complex, formed in situ from Ti(iPrO)4, chiral 1,2‐diphenylethane‐1,2‐diol 3c and water. The chiral sufoxides were obtained in high yield (97 %) with excellent enantiomeric excess (up to 98 %). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Nanocomposite Films Obtained by Electrochemical Codeposition of Conducting Polymers and Carbon Nanotubes
Authors: Brânzoi Viorel , Pilan Luisa , Brânzoi Florina 
Published: January 2009

AbstractThe electrochemical growth of carbon nanotubes (CNTs) – conducting polymer composites offers the ability to produce three‐dimensional nanostructured films that combine the redox pseudo‐capacitive charge storage mechanism of conducting polymers with the high surface area and conductivity of CNTs [1–3]. In this paper we report the electropolymerization and characterization of polypyrrole films (PPy) doped with poly (m‐aminobenzenesulfonic acid) (PABS) functionalized single‐walled carbon nanotubes (SWCNTs) (PPy/CNTs). The negatively charged CNTs served as anionic dopant during the electropolymerization to synthesize PPy/CNTs composite films. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and scanning electron microscopy (SEM) were used to investigate the electrochemical properties of the composite films.
Caffeic acid phenethyl ester decreases cholangiocarcinoma growth by inhibition of NF‐κB and induction of apoptosis
Authors: Onori Paolo , DeMorrow Sharon , Gaudio Eugenio , Franchitto Antonio , Mancinelli Romina , Venter Julie , Kopriva Shelley , Ueno Yoshiyuki , Alvaro Domenico , Savage Jennifer , Alpini Gianfranco , Francis Heather 
Published: January 2009

AbstractCaffeic acid phenethyl ester (CAPE) inhibits the growth of tumor cells and is a known inhibitor of nuclear factor kappa beta (NF‐κB), which is constitutively active in cholangiocarcinoma (CCH) cells. We evaluated the effects of CAPE on CCH growth bothin vitroandin vivo.Inhibition of NF‐κB DNA‐binding activity was confirmed in nuclear extracts treated with CAPE at 50, 40 and 20 μM. CAPE decreases the expression of NF‐κB1 (p50) and RelA (p65). CAPE decreased the growth of a number of CCH cells but not normal cholangiocytes. Cell cycle decrease was seen by a decrease in PCNA protein expression and the number of BrdU‐positive cells treated with CAPE at 20 μM compared to vehicle. Inhibition of growth and increased cell cycle arrest of Mz‐ChA‐1 cells by CAPE were coupled with increased apoptosis. Bax expression was increased, whereas Bcl‐2 was decreased in cells treated with CAPE compared to vehicle.In vivostudies were performed in BALB/c nude (nu/nu) mice implanted subcutaneously with Mz‐ChA‐1 cells and treated with daily IP injections of DMSO or CAPE (10 mg/kg body weight in DMSO) for 77 days. Tumor growth was decreased and tumor latency was increased 2‐fold in CAPE compared to vehicle‐treated nude mice. In tumor samples, decreased CCH growth by CAPE was coupled with increased apoptosis. CAPE bothin vivoandin vitrodecreases the growth of CCH cells by increasing apoptosis. These results demonstrate that CAPE might be an important therapeutic tool in the treatment of CCH. © 2009 UICC
Increased levels of copper efflux transporter ATP7B are associated with poor outcome in colorectal cancer patients receiving oxaliplatin‐based chemotherapy
Authors: Martinez‐Balibrea Eva , Martínez‐Cardús Anna , Musulén Eva , Ginés Alba , Manzano José Luis , Aranda Enrique , Plasencia Carmen , Neamati Nouri , Abad Albert 
Published: January 2009

AbstractRecently, the copper efflux transporters ATP7B and ATP7A have been implicated in the transport of and resistance to platinum drugs in breast and ovarian cancers. Because of the extensive use of oxaliplatin in colorectal cancer (CRC), we examined the expression of both transporters in tumors from CRC patients treated with oxaliplatin/5FU and sought to determine whether their expression can predict clinical outcome in these patients. ATP7B and ATP7A levels were determined by quantitative real‐time PCR in 50 primary tumors of previously untreated patients with advanced colorectal adenocarcinoma who were subsequently treated with oxaliplatin/5FU. Additionally, ATP7B protein expression was assessed by immunohistochemical staining using a tissue microarray. Patients with the lowest mRNA expression levels of ATP7B had a significantly longer time to progression (TTP) (p = 0.0009) than patients with the highest levels (12.14 months vs. 6.43 months) who also had an increased risk of progression (HR = 3.56; 95% CI, 1.6–7.9; p = 0.002). Furthermore, patients with low levels of both protein and mRNA of ATP7B derived the maximum benefit from oxaliplatin/5FU with the longest TTP as compared with patients with high levels of ATP7B protein and mRNA (14.64 months vs. 4.63 months, respectively, p = 0.01) and showed a nonsignificant trend toward a lower response rate (37.5% and 75%, respectively). In conclusion, ATP7B mRNA and protein expression in colorectal tumors is associated with clinical outcome to oxaliplatin/5FU. Prospective studies are required to evaluate the role of this marker in tailoring chemotherapy. © 2009 UICC
TMF/ARA160 downregulates proangiogenic genes and attenuates the progression of PC3 xenografts
Authors: Abrham Galya , Volpe Marina , Shpungin Sally , Nir Uri 
Published: January 2009

AbstractTMF/ARA160 is a Golgi‐associated protein whose level is downregulated in solid tumors. TMF changes its subcellular localization on exposure of cells to stress cues, thereby, directing proteins, such as the key transcription factor, Stat3, to proteasomal degradation. Here, we show that enforced ectopic expression of HA‐TMF in PC3 prostate carcinoma cells, which do not express Stat3, significantly attenuated the development and growth of xenograft tumors elicited by these cells in athymic mice. Immunohistochemical analysis revealed impaired angiogenesis and accelerated onset of apoptosis in the HA‐TMF‐expressing tumors. RNA expression profiling revealed the downregulation of several proangiogenic genes in HA‐TMF‐expressing xenografts. Among these were the interleukin‐8 and interleukin‐1β genes, whose expression is controlled by nuclear factor‐kB. The level of the nuclear factor‐kB component, p65/RelA, was decreased in HA‐TMF‐expressing xenografts, and TMF was found to direct the ubiquitination and proteasomal degradation of p65/RelA in metabolically stressed PC3 clones. Taken together, our findings indicate that TMF/ARA160 is a regulator of key transcription factors under metabolic constraints, thereby affecting angiogenesis and progression of solid tumors, which are subjected to metabolic stress. © 2009 UICC
High serum interleukin‐6 level predicts future hepatocellular carcinoma development in patients with chronic hepatitis B
Authors: Wong Vincent Wai‐Sun , Yu Jun , Cheng Alfred Sze‐Lok , Wong Grace Lai‐Hung , Chan Hoi‐Yun , Chu Eagle Siu‐Hong , Ng Enders Kai‐On , Chan Francis Ka‐Leung , Sung Joseph Jao‐Yao , Chan Henry Lik‐Yuen 
Published: January 2009

AbstractIncreased interleukin‐6 (IL‐6) production is implicated in the pathogenesis of hepatocellular carcinoma (HCC) in animal models. Although previous studies showed that HCC patients had higher serum IL‐6 level at the time of diagnosis, it is unclear if the cytokine contributes to the development of HCC or is just a reaction to cancer. To address this question, we performed a nested case‐control study. Consecutive chronic hepatitis B patients were recruited from 1997 to 2000 and followed till 2008. Profiling of 27 cytokines, chemokines and growth factors was performed at baseline, date of peak alanine aminotransferase (ALT) level and the last visit. Thirty‐seven patients developed HCC at a median follow‐up of 62 months (interquartile range: 41–110). Serum IL‐6 was higher in patients with HCC than controls both during peak ALT and at the last visit (both p = 0.02). Patients with IL‐6 above 7 pg/ml during peak ALT had increased risk of HCC or death (adjusted hazard ratio 3.0; 95% confidence interval 1.2, 7.8; p = 0.02). The sensitivity, specificity, positive and negative predictive values of this cutoff to predict future HCC development were 70%, 73%, 72% and 71%, respectively. Combination of IL‐6 and AFP improved the sensitivity in diagnosing HCC or predicting future HCC development. In conclusion, high serum IL‐6 level predates the development of HCC in chronic hepatitis B patients, and has moderate accuracy in predicting future cancer. This may assist clinicians in selecting high‐risk patients for HCC surveillance program. © 2009 UICC