bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermostable Transketolase from Geobacillus stearothermophilus: Characterization and Catalytic Properties
Authors: Abdoul‐Zabar Juliane , Sorel Isabelle , Hélaine Virgil , Charmantray Franck , Devamani Titu , Yi Dong , de Berardinis Véronique , Louis Dominique , Marlière Philippe , Fessner Wolf‐Dieter , Hecquet Laurence 
Published: December 2012

AbstractHere we have characterized the first transketolase (TK) from a thermophilic microorganism, Geobacillus stearothermophilus, which was expressed from a synthetic gene in Escherichia coli. The G. stearothermophilus TK (mTKgst) retained 100% activity for one week at 50 °C and for 3 days at 65 °C, and has an optimum temperature range around 60–70 °C, which will be useful for preparative applications and for future biocatalyst development. The thermostability of the mTKgst allowed us to carry out an easy, one‐step purification by heat shock treatment of crude cell extracts at 65 °C for 45 min, directly yielding 132 mg of pure mTKgst from 1 L of culture. The reaction rate of mTKgst with glycolaldehyde was 14 times higher at 70 °C than at 20 °C, and 4 times higher at 50 °C when compared to E. coli TK under identical conditions. When tested at 50 °C with other aldehydes as acceptors, mTKgst activity was approximately 3 times higher than those obtained at 20 °C. Applications of this new TK in biocatalysis were performed with hydroxypyruvate as donor and three different aldehydes as acceptors – glycolaldehyde, D‐glyceraldehyde and butyraldehyde – from which the corresponding products L‐erythrulose 1, D‐xylulose 2 and 1,3‐dihydroxyhexan‐2‐one 3 were obtained, respectively. The optical rotations for products 1 and 2 indicate that the stereospecificity of mTKgst is identical to that of other TK sources, leading to a (3S) configuration. With the non‐hydroxylated substrate, butanal, the ee value was 85% (3S), showing higher enantioselectivity than the E. coli TK (75% ee, 3S). Processes at elevated temperatures could offer opportunities to extend the applications of TK biocatalysis, by favoring hydrophobic aldehyde acceptor substrate solubility and tolerance towards non‐conventional media.
Multidimensional high‐temperature liquid chromatography: A new technique to characterize the chemical heterogeneity of Ziegler‐Natta‐based bimodal HDPE
Authors: Ginzburg Anton , Macko Tibor , Dolle Volker , Brüll Robert 
Published: December 2012

AbstractHigh temperature two‐dimensional liquid chromatography (HT 2D‐LC) was recently introduced as a new technique to analyze the heterogeneities with regard to composition and molar mass present in model blends of polyolefins and various olefin copolymers. The method uses graphite as stationary phase and solvent gradients of 1‐decanol → 1,2,4‐trichlorobenzene as mobile phase for the compositional separation. With the aim to maximize the chromatographic resolution, the influence of the separation's temperature in the first dimension was evaluated: approaching the θ‐temperature of polyethylene (PE) in 1‐decanol selectively enhances the retention of higher molar mass PE standards while that of the lower molar mass ones is hardly affected. A bimodal ethylene/1‐butene copolymer and its temperature rising elution fraction (TREF) fractions were separated by HT 2D‐LC. For the first time, both axes of the contour plot were calibrated with regard to chemical composition and molar mass, respectively. Prefractionation of the bulk sample by TREF enhances the detectability of separated components of the 2D separation. The influence of the separation temperature, that is, working around the θ‐temperature of PE in 1‐decanol, can be used to enhance the chromatographic resolution of the 2D chromatography. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Circulating Citrullinated Vimentin Fragments Reflect Disease Burden in Ankylosing Spondylitis and Have Prognostic Capacity for Radiographic Progression
Authors: Bay‐Jensen Anne C. , Karsdal Morten A. , Vassiliadis Efstathios , Wichuk Stephanie , Marcher‐Mikkelsen Kathrine , Lories Rik , Christiansen Claus , Maksymowych Walter P. 
Published: December 2012

AbstractObjectiveAnkylosing spondylitis (AS) has been considered a seronegative rheumatic disease based on absent or low levels of antibodies against citrullinated proteins. The present study was undertaken to evaluate whether a citrullinated and matrix metalloproteinase–degraded fragment of vimentin (VICM) could be a prognostic biomarker in AS.MethodsVICM was measured in serum samples from healthy controls (n = 35), control patients with rheumatoid arthritis (RA) (n = 47), and patients with AS (n = 201). The optimal cutoff for diagnostic sensitivity and specificity was determined by receiver operating characteristic curve analysis. Baseline and 2‐year spine radiographs were available from 118 AS patients, and were scored using the modified Stoke AS Spine Score (mSASSS). We assessed correlations with patient demographic characteristics (age, disease duration), disease activity (Bath AS Disease Activity Index [BASDAI], C‐reactive protein level), and disease severity (mSASSS) using Spearman's rho. The independent association of VICM with 2‐year radiographic progression, defined as a change of >0 in the mSASSS or the development of a new syndesmophyte, was analyzed by multivariate regression.ResultsLevels of degraded VICM were significantly higher in both RA patients and AS patients than in healthy controls (both P < 0.001). AS patients with the highest levels of VICM had the largest burden of disease (P < 0.01), i.e., highest mSASSS score and BASDAI. VICM levels were significantly and independently associated with radiographic progression after 2 years (β = 0.69, P = 0.0005). Patients with both a high VICM level and a high baseline mSASSS had the highest risk of radiographic progression (odds ratio 13 for mSASSS change, 32 for new syndesmophytes), with progression occurring in 67% of these patients.ConclusionThe present findings show that serum VICM may be of prognostic value in AS. The data also suggest that citrullination may be relevant in AS pathogenesis.
Development of A Behavior‐Based Cooperative Search Strategy for Distributed Autonomous Mobile Robots Using Zigbee Wireless Sensor Network
Authors: Shih Tzu‐Chiang , Yeh Syh‐Shiuh , Hsu Pau‐Lo 
Published: December 2012

AbstractTo achieve efficient and objective search tasks in an unknown environment, a cooperative search strategy for distributed autonomous mobile robots is developed using a behavior‐based control framework with individual and group behaviors. The sensing information of each mobile robot activates the individual behaviors to facilitate autonomous search tasks to avoid obstacles. An 802.15.4 ZigBee wireless sensor network then activates the group behaviors that enable cooperative search among the mobile robots. An unknown environment is dynamically divided into several sub‐areas according to the locations and sensing data of the autonomous mobile robots. The group behaviors then enable the distributed autonomous mobile robots to scatter and move in the search environment. The developed cooperative search strategy successfully reduces the search time within the test environments by 22.67% (simulation results) and 31.15% (experimental results).
Biofilm model calibration and microbial diversity study using Monte Carlo simulations
Authors: Brockmann D. , Caylet A. , Escudié R. , Steyer J.‐P. , Bernet N. 
Published: December 2012

AbstractMathematical models are useful tools for studying and exploring biological conversion processes as well as microbial competition in biological treatment processes. A single‐species biofilm model was used to describe biofilm reactor operation at three different hydraulic retention times (HRT). The single‐species biofilm model was calibrated with sparse experimental data using the Monte Carlo filtering method. This calibrated single‐species biofilm model was then extended to a multi‐species model considering 10 different heterotrophic bacteria. The aim was to study microbial diversity in bulk phase biomass and biofilm, as well as the competition between suspended and attached biomass. At steady state and independently of the HRT, Monte Carlo simulations resulted only in one unique dominating bacterial species for suspended and attached biomass. The dominating bacterial species was determined by the highest specific substrate affinity (ratio of µ/KS). At a short HRT of 20 min, the structure of the microbial community in the bulk liquid was determined by biomass detached from the biofilm. At a long HRT of 8 h, both biofilm detachment and microbial growth in the bulk liquid influenced the microbial community distribution. Biotechnol. Bioeng. 2013; 110: 1323–1332. © 2012 Wiley Periodicals, Inc.
Oxygen transfer characteristics of miniaturized bioreactor systems
Authors: Kirk Timothy V. , Szita Nicolas 
Published: December 2012

AbstractSince their introduction in 2001 miniaturized bioreactor systems have made great advances in function and performance. In this article the dissolved oxygen (DO) transfer performance of submilliliter microbioreactors, and 1–10 mL minibioreactors was examined. Microbioreactors have reached kLa values of 460 h−1, and are offering instrumentation and some functionality comparable to production systems, but at high throughput screening volumes. Minibioreactors, aside from one 1,440 h−1 kLa system, have not offered as high rates of DO transfer, but have demonstrated superior integration with automated fluid handling systems. Microbioreactors have been typically limited to studies with E. coli, while minibioreactors have offered greater versatility in this regard. Further, mathematical relationships confirming the applicability of kLa measurements across all scales have been derived, and alternatives to fluorescence lifetime DO sensors have been evaluated. Finally, the influence on reactor performance of oxygen uptake rate (OUR), and the possibility of its real‐time measurement have been explored. Biotechnol. Bioeng. 2013; 110: 1005–1019. © 2012 Wiley Periodicals, Inc.
Intravenous injection of neural progenitor cells facilitates angiogenesis after cerebral ischemia
Authors: Moriyama Yoshiyuki , Takagi Norio , Hashimura Kanae , Itokawa Chisa , Tanonaka Kouichi 
Published: December 2012

AbstractEarlier we demonstrated that the injection of neural progenitor cells (NPCs) has therapeutic potential for the improvement of learning dysfunction after cerebral ischemia. However, it remained to be clarified how transplantation of NPCs can improve ischemia‐induced dysfunction. In this study, we examined whether intravenous injection of NPCs after cerebral ischemia could enhance angiogenesis by affecting the expression of angiogenic factors. The injection of NPCs on day 7 after cerebral ischemia enhanced angiogenesis on day 28. Vascular endothelial growth factor (VEGF) and its receptor VEGFR2 were increased in expression by the NPC injection. The level of angiopoietin‐1 (Ang‐1), an angiogenic factor, but not that of Ang‐2, which acts as an antagonist for the Ang‐1 receptor, was also increased on day 28. In addition, the expression of Ang‐1 receptor Tie2 was enhanced in brain capillaries. Furthermore, the amounts of tight junctional proteins, which are in the blood–brain barrier and whose expression occurs downstream of Ang‐1/Tie2 signaling, were increased by the NPC injection. These results suggest that the NPC injection promoted angiogenesis through Ang‐1/Tie2 and/or VEGF/VEGFR2 signaling in brain capillaries after cerebral ischemia. Such signaling might have the potential for causing vascular stabilization and maturation for a long period after cerebral ischemia.
Salen‐Based Coordination Polymers of Manganese and the Rare‐Earth Elements: Synthesis and Catalytic Aerobic Epoxidation of Olefins
Authors: Bhunia Asamanjoy , Gotthardt Meike A. , Yadav Munendra , Gamer Michael T. , Eichhöfer Andreas , Kleist Wolfgang , Roesky Peter W. 
Published: December 2012

AbstractTreatment of N,N′‐bis(4carboxysalicylidene)ethylenediamine (H4L), with MnCl2⋅(H2O)4, and Ln(NO3)3⋅(H2O)m (Ln=Nd, Eu, Gd, Dy, Tb), in the presence of N,N‐dimethylformamide (DMF)/pyridine at elevated temperature resulted (after work up) in the formation of 1D coordination polymers {[Ln2(MnLCl)2(NO3)2(dmf)5]⋅4 DMF}n (1–5). In these coordination polymers the rare earth ions are connected through carboxylate groups from Mn–salen units in a 1D chain structure. Thus, the Mn–salen complex acts as a “metalloligand” with open coordination sites. All compounds were used as catalysts in the liquid‐phase epoxidation of trans‐stilbene with molecular oxygen, which resulted in the formation of stilbene oxide. Since the choice of the lanthanide had virtually no influence on the performance of the catalyst, only the manganese–gadolinium was studied in detail. The influence of solvent, catalyst concentration, reaction temperature, oxidant, and oxidant flow rate on conversion, yield, and selectivity was analyzed. A conversion of up to 70 %, the formation of 61 % stilbene oxide (88 % selectivity), and a TON of 84 were observed after 24 h. A hot filtration test confirmed that the reaction is mainly catalyzed through a heterogeneous pathway, although a minor contribution of homogeneous species could not be completely excluded. The catalyst could be reused without significant loss of activity.
Reactivity of AllylSmBr/HMPA: Facile Synthesis of 3‐Aryl‐1,2,4‐benzotriazines
Authors: Yin Ruifeng , Zhou Liejin , Liu Huili , Mao Hui , Lü Xin , Wang Xiaoxia 
Published: December 2012

Abstract3‐Aryl‐1,2,4‐benzotriazines were conveniently prepared in moderate to good yields from 1,l‐bis(benzotriazol‐1‐yl)methylarenes with allylsamarium bromide/hexamethylphosphramide (allylSmBr/HMPA). Preliminary results indicate that HMPA may enhance the reducing ability as well as prohibit the nucleophicility of allylSmBr, thus making allylSmBr/HMPA as a promising single‐electron transfer (SET) reagent.
A Concise Total Synthesis of Amphidinin B
Authors: Wu Dongdong , Wu Jinlong , Dai Wei‐min 
Published: December 2012

AbstractA concise total synthesis of amphidinin B, a cytotoxic linear dicarboxylic acid associated with amphidinolide T marine macrolides, has been accomplished from the 19‐membered cycloalkene intermediates designed for diverted total synthesis of amphidinolide T1 and T3–T5. The 1H and 13C NMR spectra of the synthesized amphidinin B in C6D6 and CDCl3 were compared with those for the natural and synthetic forms reported in the literature, showing solvent‐dependence of the 1H and 13C NMR signals of amphidinin B in C6D6 and CDCl3.
Design and Synthesis of Polymeric Chiral Bicyclo[3.3.0] Diene as Reusable Ligand for Rhodium‐Catalyzed Asymmetric 1,4‐Addition
Authors: Yang Hongyu , Xu Minghua 
Published: December 2012

AbstractA series of A‐B type sterically regular bicyclio[3.3.0] diene‐based polymers were designed and synthesized as immobilized chiral diene ligands for asymmetric catalysis. With polymeric diene 6b, good to excellent enantioselectivities can be achieved in Rh‐catalyzed asymmetric 1,4‐addition of arylboronic acids to α,β‐unsaturated ketones.
Microbial Transformation of Pregnane‐3β,16β,20‐triol by Cunninghamella echinulata
Authors: Yang Chenru , Fan Huafang , Yuan Yuan , Gao Jinming 
Published: December 2012

AbstractMicrobial transformation of pregnane‐3β,16β,20‐triol (1) by Cunninghamella echinulata afforded four previously unreported polyhydroxylated steroids, namely pregnane‐3β,14α,16β,20‐tetrol (2), pregnane‐3‐oxo‐14α, 16β,20‐triol (3), pregnane‐3‐oxo‐7β,16β,20‐triol (4), and pregnane‐3β,7β,16β,20‐tetrol (5). The structures of these metabolites were established by means of spectroscopic analysis (1D and 2D NMR as well as HRESIMS analysis).
Monitoring of Microbiological Attributes of Soil and Groundwater Exposed to Metal Industrial Effluents
Authors: Rawat Monica , Rai Jaiprakash N. 
Published: December 2012

AbstractThe present paper evaluates the temporal and spatial impact of heavy metal containing (Cr, Zn, Cu, Ni, Cd and Fe) effluents of brass, electroplating and tannery industries on chemical and microbiological characteristics of affected soil and groundwater. Therefore, samples were drawn from three sites, S1, S2 and S3, with a longitudinally distant from effluent drain of 20, 200 and 700 m, respectively. In general, the metals concentration exceeded the standard limits not only in the discharged effluents but also in the soil and groundwater. The significant reduction of microbial biomass C and N, soil respiration and microbial coefficient with increasing metal content from S3 to S1 was recorded, the effect being more pronounced in summer. However, the Cmic/Nmic ratio decreased whilst the metabolic quotient ($q_{{\rm CO}_{{\rm 2}} } $) increased with increasing metal concentration in soil. The content of Zn (11.5 mg/L) and Bacillus sp. was at maximum in groundwater of brass and electroplating industry site, whereas that of tannery site contained maximum Cr (2.34 mg/L) and Enterobacter sp. The toxic metals adversely polluted the groundwater which made it to harbours Escherichia coli beyond the prescribed limit. To check the soil and groundwater pollution, eco‐friendly measures involving improved effluent treatment technology and site‐specific application of treated effluent are recommended.
Hydrosoluble Benzo[e]pyridoindolones as Potent Inhibitors of Aurora Kinases
Authors: Le Ly‐Thuy‐Tram , Vu Hong‐Lien , Naud‐Martin Delphine , Bombled Marianne , Nguyen Chi‐Hung , Molla Annie 
Published: December 2012

AbstractAurora kinases play an essential role in mitotic progression and are potentially druggable targets in cancer therapy. We identified benzo[e]pyridoindoles (BePI) as powerful aurora kinase inhibitors. Their efficiency was demonstrated both in enzymatic inhibition studies and in cell culture assays. New BePI molecules were synthesized, and a structure–activity relationship study was conducted with the aim of improving the activity and solubility of the lead compound. Tetracyclic BePI derivatives are characterized by a particular curved shape, and the presence of an oxo group on the pyridine ring was found to be required for aurora kinase B inhibition. New hydrosoluble benzo[e]pyridoindolones were subsequently designed, and their efficacy was tested by a combination of cell‐cycle analysis and time‐lapse experiments in live cells. The most active BePI derivative, 13 b, inhibited the cell cycle, drove cells to polyploidy, and eventually induced apoptosis. It exhibited high antiproliferative activity in HeLa cells with an IC50 value of 63 nM. Relative to compounds tested in clinical trials, this antiproliferative potency places 13 b among the top 10 aurora kinase inhibitors. Our results justify further in vivo evaluation in preclinical animal models of cancer.
Synthesis of Stable Phosphomide Ligands and their Use in Ru‐Catalyzed Hydrogenations of Bicarbonate and Related Substrates
Authors: Gowrisankar Saravanan , Federsel Christopher , Neumann Helfried , Ziebart Carolin , Jackstell Ralf , Spannenberg Anke , Beller Matthias 
Published: December 2012

AbstractNew benzoyl‐ and naphthoyl‐substituted phosphines have been synthesized, which are stable to air and moisture. Testing these so‐called phosphomide ligands in the presence of different ruthenium precursors, the hydrogenation of sodium bicarbonate (NaHCO3) to sodium formate (NaHCO2) proceeded with good catalyst turnover numbers in the range of 1300–1600 at 80 °C and a total pressure of hydrogen of 60 bar in the absence of amines or other additives. Similarly, catalytic hydrogenations of carbon dioxide, cinnam‐, and benzaldehyde were possible with these new ruthenium complexes. As an intermediate of the catalytic cycle the defined ruthenium complex [(η6‐C6H6)‐RuCl2(Cy2P(1‐naphthoyl)] (Cy=cyclohexyl) was prepared and characterized by X‐ray crystallography.
Synthesis of 4‐(Carbonyloxyphenyl)‐1,4‐Dihydropyridines as Potential Antihypertensive Agents
Authors: Bansal Ranju , Narang Gaurav , Calle Carmen , Carron Rosalia , Pemberton Karen , Harvey Alan L. 
Published: December 2012

Abstract

Preclinical Research

A series of novel symmetric and asymmetric 4‐(carbonyloxyphenyl)‐1,4‐dihydropyridines (DHPs) was synthesized and evaluated for calcium channel blocking, vasodilatory and antihypertensive properties. Some of these new DHPs displayed potent calcium channel blocking and good vasodilatory activities. Heart rate remained relatively constant in comparison with blood pressure changes in the case of these newly synthesized compounds, thereby decreasing the probability of reflex tachycardia, a major side effect of nifedipine. The most potent compound, ethyl methyl 4‐(3‐isopropylcarbonyloxyphenyl)‐2,6‐dimethyl‐1,4‐dihydropyridine‐3,5‐dicarboxylate (14c) exhibited antihypertensive activity comparable with the standard drug—nifedipine.
Should we change the target blood pressure in diabetic patients?
Authors: Shlomai Gadi , Grossman Ehud 
Published: December 2012

SummaryHypertension is a major modifiable risk factor for cardiovascular morbidity and mortality in diabetic patients. Guidelines recommend lowering blood pressure (BP) to less than 130/80 mmHg in diabetic patients. These recommendations are based on several studies in diabetic patients that showed the benefit of intensive BP control. However in all the studies the achieved BP was higher than 130/80 mmHg. Re‐evaluation of earlier studies, as well as more recently accumulated data suggest that intensive BP control is associated with a significant reduction in all‐cause mortality and stroke rate, but with no benefit for other microvascular or macrovascular (cardiac, renal and retinal) outcomes. Intensive BP control is associated with an increased risk of serious adverse effects, particularly for systolic BPs levels lower than 130 mmHg. When determining the target BP in diabetic patients one should balance the potential cerebrovascular protection against the increased risk of serious side effects, and the absence of benefit for other circulatory system. It seems therefore, that lowering BP to levels close to 130/80 mmHg should be the main goal of treatment in diabetic patients.
Obesity in Asia – is it different from rest of the world
Authors: Ramachandran Ambady , Chamukuttan Snehalatha , Shetty Samith A. , Arun Nanditha , Susairaj Priscilla 
Published: December 2012

SummaryAn epidemic of obesity and obesity related diseases such as diabetes and cardio vascular disease (CVD) is prevalent in many Asian countries. Migration from rural to urban areas, and rapid socio‐economic transition are associated with the lifestyle changes resulting in decreased levels of physical activity and increased intake of energy dense diet.
Prevention of diabetes: a strategic approach for individual patients
Authors: Shin Jeong‐Ah , Lee Jin‐Hee , Kim Hun‐Sung , Choi Yoon‐Hee , Cho Jae‐Hyoung , Yoon Kun‐Ho 
Published: December 2012

SummaryThe ‘diabetes epidemic’ is an important health and socioeconomic problem worldwide. Type 2 diabetes is a chronic disease with gradual deterioration in glucose metabolism which causes multiple systemic complications. Therefore, early intervention in the prediabetic stage is a valuable approach to reduce diabetes development and related complications. Many clinical trials have suggested that lifestyle intervention, including moderate‐intensity exercise and diet control, and pharmacologic intervention using metformin, α‐glucosidase inhibitors, thiazolidinediones, anti‐obesity drugs and incretin mimics, are effective in preventing diabetes development. However, an individualized approach with careful consideration of the patient’s risk status and health economics is needed to perform a successful intervention programmes. In this review, we will summarize the known evidence on treatment‐ and cost‐effectiveness of drug and lifestyle treatment. Additionally, we will propose a strategic approach algorithm that is applicable to clinical practice.