bluuebunny/crossref_metadata_2025 huggingface dataset:
Exercise Capacity in Prepubertal Children with Cystic Fibrosis
Authors: Kilbride Emma , Widger John , Hussey Juliette , El Nazir Basil , Greally Peter
Published: July 2012

Background. Patients with cystic fibrosis (CF) are observed to have diminished lung function, nutritional status, and aerobic exercise capacity. All three parameters are related to prognosis and survival. However, there is little information regarding these parameters in prepubertal patients. Methods. Our study groups consisted of sixteen patients with CF (7 girls) and 99 healthy volunteers (52 girls). Subjects performed spirometry and a progressive exercise test to exhaustion on a cycle ergometer. Leg muscle strength was measured using an isokinetic dynamometer. Physical activity was examined using the modifiable activity questionnaire and accelerometer. Results. Nutritional status was similar between groups (BMI—boys control versus CF 18.5 versus 17.9, girls control versus CF 19.5 versus 17.4). Girls with CF were significantly smaller and lighter than controls. Lung function was significantly reduced in CF groups (FEV1—boys control versus CF 91% versus 84%, girls control versus CF 90% versus 82%). Patients with CF were as active and as fit as their healthy controls. Conclusion. In this group of prepubertal children with CF, nutritional status was comparable to healthy children of the same age. Their aerobic exercise tolerance and peripheral muscle strength were also relatively well preserved despite significantly lower lung function.
Center-Vortex Loops with One Self-Intersection
Authors: Moosmann Julian , Hofmann Ralf
Published: July 2012

We investigate the 2D behavior of one-fold self-intersecting, topologically stabilized center-vortex loops in the confining phase of an SU(2) Yang-Mills theory. This coarse-graining is described by curve-shrinking evolution of center-vortex loops immersed in a flat 2D plane driving the renormalization-group flow of an effective “action.” We observe that the system evolves into a highly ordered state at finite noise level, and we speculate that this feature is connected with 2D planar high Tc superconductivity in FeAs systems.
Simulation Analysis of Threshold Autoregressive Unit Root Tests
Authors: Cook Steve
Published: July 2012

Using numerical simulation, the finite-sample properties of threshold autoregressive (TAR) and momentum-threshold (MTAR) autoregressive-based unit root tests under both deterministic and consistent methods of threshold estimation are examined in the presence of generalised autoregressive conditional heteroskedasticity (GARCH). Previous research is extended by considering both the impact of alternative robust methods of covariance matrix estimation and the behaviour of the secondary tests of asymmetry associated with the TAR and MTAR models. The results obtained reveal many interesting features, in particular the distortionary effects of consistent-threshold estimation. In summary, the findings presented indicate that caution should be exercised when interpreting the results of these frequently employed threshold-based testing methods.
Predictors of Prolonged Stay in the Intensive Care Unit following Cardiac Surgery
Authors: Eltheni Rokeia , Giakoumidakis Konstantinos , Brokalaki Hero , Galanis Petros , Nenekidis Ioannis , Fildissis George
Published: July 2012

The prediction of intensive care unit length of stay (ICU-LOS) could contribute to more efficient ICU resources' allocation and better planning of care among cardiac surgery patients. The aim of this study was to identify the preoperative and intraoperative predictors for prolonged cardiac surgery ICU-LOS. An observational cohort study was conducted among 150 consecutive patients, who were admitted to the cardiac surgery ICU of a tertiary hospital of Athens, Greece from September 2010 to January 2011. Multivariate regression analysis revealed that patients with increased creatinine levels preoperatively (odds ratio (OR) 3.0, P=0.049), history of atrial fibrillation (AF) (OR 6.3, P=0.012) and high EuroSCORE values (OR 2.6, P=0.017) had a significant greater probability to stay in the ICU for more than 2 days. In addition, intraoperative hyperglycemia (OR 3.0, P=0.004) was strongly associated with longer ICU-LOS. In conclusion, the high perioperative risk, the history of AF and renal dysfunction, and the intraoperative hyperglycemia are significant predictors of prolonged ICU stay. The early identification of patients at risk could allow the efficient ICU resources' allocation and the reduction of healthcare costs. This would contribute to nursing care planning depending on the availability of healthcare personnel and ICU bed capacity.
Cytokines and Growth Factors Promote Airway Smooth Muscle Cell Proliferation
Authors: Stamatiou R. , Paraskeva E. , Gourgoulianis K. , Molyvdas P.-A. , Hatziefthimiou A.
Published: July 2012

Chronic airway diseases, such as asthma or chronic obstructive pulmonary disease, are characterized by the presence in the airways of inflammation factors, growth factors and cytokines, which promote airway wall remodelling. The aim of this study was to investigate the effect of cytokines and growth factors on airway smooth muscle cell (ASMC) proliferation, phenotype and responsiveness. Incubation of serum starved human bronchial ASMCs with TNF-α, TGF, bFGF, and PDGF, but not IL-1β, increased methyl-[3H]thymidine incorporation and cell number, mediated by the PI3K and MAPK signalling pathways. Regarding rabbit tracheal ASMC proliferation, TNF-α, IL-1β, TGF, and PDGF increased methyl-[3H]thymidine incorporation in a PI3K- and MAPK-dependent manner. bFGF increased both methyl-[3H]thymidine incorporation and cell number. Moreover, incubation with TGF, bFGF and PDGF appears to drive human ASMCs towards a synthetic phenotype, as shown by the reduction of the percentage of cells expressing SM-αactin. In addition, the responsiveness of epithelium-denuded rabbit tracheal strips to carbachol was not significantly altered after 3-day treatment with bFGF. In conclusion, all the tested cytokines and growth factors increased ASMC proliferation to a different degree, depending on the specific cell type, with bronchial ASMCs being more prone to proliferation than tracheal ASMCs.
Monte Carlo Study of Magnetism of the Fe/Gd Multilayers: Dependence on the Layers Thickness and Interface Morphology
Authors: Razouk Abdelati , Sahlaoui Mohamed , Sajieddine Mohamed
Published: July 2012

We present the results of the Monte Carlo simulations of Fe/Gd multilayers and a comparison of the models studied with experimental results. The Heisenberg model interactions are considered for both ferromagnetic and antiferromagnetic cases. At thermal equilibrium magnetization, the Curie temperature is investigated for different thicknesses of Fe layers and interface morphology in Fe/Gd multilayers. It turns out that the magnetic properties of the Fe/Gd multilayers strongly depend on magnetization amplitude with interface composition, the spatial arrangement of magnetic atoms, and the thickness of Fe layers.
Comparison of the Anterior Limit of the Dentition in Patients Treated with Self-Ligating Straight-Wire, Conventional Straight-Wire and Standard Edgewise Appliances
Authors: Lombardo Luca , Ficara Paolo , Maltoni Ivano , Moser Lorenz , Guarneri Maria Paola , Siciliani Giuseppe
Published: July 2012

The aim of this study was to identify and compare any differences in the position of the anterior limit of the dentition provoked by three different types of orthodontic mechanics: traditional edgewise, straightwire and self-ligating. A sample of 54 patients (selected from a group of 289 patients) possessed a range of Little’s Irregularity Index values for the upper and lower dental arches between a minimum of 6.5 and a maximum of 13.5 at T0, and corresponding final values no greater than 2 and hence of minimal irregularity. The 54 patients were subdivided into three groups according to the type of brackets used in their treatment: Group 1 was composed of 24 patients treated using the self-ligating technique, Group 2 of 15 patients treated using a conventional straight-wire technique (Roth) and Group 3 of 15 patients treated using the standard edgewise technique. Cephalometric tracings were performed on laterolateral teleradiography. Group 1 value was found to be nonsignificant, whereas significant labial inclination was noted in Groups 2 and 3 (). A significant labial inclination of the upper incisors was also evidenced in all three sample groups.
Amenability of the Restricted Fourier Algebras
Authors: Amini Massoud , Shams Yousefi Marzieh
Published: July 2012

We discuss amenability of the restricted Fourier-Stieltjes algebras on inverse semigroups. We show that, for an E-unitary inverse semigroup, amenability of the restricted Fourier-Stieltjes algebra is related to the amenability of an associated Banach algebra on a Fell bundle.
An Experimental Study of Vegetable Solar Drying Systems with and without Auxiliary Heat
Authors: Khalifa Abdul Jabbar N. , Al-Dabagh Amer M. , Al-Mehemdi W. M.
Published: July 2012

An experimental study is conducted to investigate the performance of a solely solar drying system and a system equipped with an auxiliary heater as a supplement to the solar heat. The performances of both are compared to that of natural drying. Beans and peas are dehydrated in a system that consists of two flat plate collectors, a blower, and a drying chamber. Tests with four different airflow rates, namely, 0.0383, 0.05104, 0.0638, and 0.07655 m3/s are conducted. It was found that the drying time was reduced from 56 hours for natural drying to 12–14 hours for solar drying and to 8-9 hours for mixed (solar and auxiliary) drying. The efficiency of the mixed drying system was found to increase by 25% to 40% compared to the solely solar drying. A best fit to the experimental data of peas and beans was obtained by six exponential equations for the various systems with a correlation coefficient in the range 0.933 and 0.997.
Evaluation of Oral Robenacoxib for the Treatment of Postoperative Pain and Inflammation in Cats: Results of a Randomized Clinical Trial
Authors: King Stephen , Roberts Elizabeth S. , Roycroft Linda M. , King Jonathan N.
Published: July 2012

The efficacy and safety of robenacoxib were assessed for the control of postoperative pain and inflammation in cats. The study was a multicenter, prospective, randomized, blinded, and parallel group clinical trial. A total of 249 client-owned cats scheduled for forelimb onychectomy plus either ovariohysterectomy or castration surgeries were included. All cats received butorphanol prior to anesthesia and forelimb four-point regional nerve blocks with bupivacaine after induction of general anesthesia. Cats were randomized to receive daily oral tablet robenacoxib, at a mean (range) dosage of 1.84 (1.03–2.40) mg/kg , or placebo , once prior to surgery and for two days postoperatively. Significantly fewer robenacoxib cats received additional analgesia rescue therapy (16.5%) than placebo cats (46.3%). Pain elicited on palpation of the soft tissue incision site, behavior following social interaction, and posture assessed during the first 8 hours after extubation were significantly improved in cats receiving robenacoxib. Frequency of reported adverse clinical signs, hematology, serum chemistry and urinalysis variables, and body weight changes weresimilar between groups. In conclusion, robenacoxib was effective and well tolerated in the control of postoperative pain and inflammation in cats undergoing onychectomy with ovariohysterectomy or castration.
Streptococcal Pharyngitis: A Prospective Study of Compliance and Complications
Authors: Sarrell E. Michael , Giveon Shmuel M.
Published: July 2012

Background. Uncertainty exists concerning the necessity of 10-day antibiotic treatment of group A beta hemolytic streptococcus (GABHS) pharyngitis. Objective. To assess the incidence of GABHS recurrence and suppurative and nonsuppurative complications in relation to compliance. Methods. (Design). Prospective cohort observational study. (Subjects). 2,000 children aged 6 months to 18 years with sore throat and positive GABHS culture. (Main Outcome Measures). Recurrence of symptomatic culture positive GABHS pharyngitis, incidence of suppurative, and long-term, regional, nonsuppurative complications of GABHS pharyngitis, over a ten year period. Results. 213 (11%) of the children received no treatment. Most children received antibiotics for only 4–6 days (in correlation with the duration of fever, which in most cases lasted up to 3 days). Three hundred and six (15.3%) children had clinically diagnosed recurrent tonsillopharyngitis; 236 (12.3%) had positive GABHS findings within 10 to 14 days and thirty-four (1.7%) within 21–30 days after the index positive GABHS culture. The remaining 1.3% had no positive culture despite the clinical findings. Almost all recurrences [236 (11.6%)] occurred within 14 days and 156 (7.6%) in the fully treated group. The presence of fever during the first 3 days of the disease was the most significant predictor for recurrence. Other predictors were the age younger than 6 years and the presence of cervical lymphadenitis. No increase in the incidence of nonsuppurative or suppurative complications was noted during the 10-year follow-up period, compared to the past incidence of those complications in Israel. Conclusions. Our data suggests that the majority of children discontinue antibiotics for GABHS tonsillopharyngitis a day or two after the fever subsides. The incidence of complications in our study was not affected by this poor compliance.
Relative Prognostic Value of Human Epidermal Growth Factor Receptor 2 (HER2) Expression in Operable Oesophagogastric Cancer
Authors: Chan David S. Y. , Campbell Fiona , Edwards Paul , Jasani Bharat , Williams Geraint T. , Lewis Wyn G.
Published: July 2012

Aims. The aim of this study was to determine the prognostic significance of HER2 receptor expression in operable oesophagogastric adenocarcinoma.
Methods. Eighty-five consecutive patients diagnosed with oesophagogastric adenocarcinoma [18 oesophageal (OC), 32 junctional (JC) and 35 gastric (GC)] undergoing potentially curative resection were studied retrospectively. Immunohistochemistry was used to determine HER2 status at endoscopic biopsy and resection specimen. The primary outcome measure was survival.
Results. Twenty (24%) patients had HER2 positive tumours which was commoner in JC (14/32, 44% versus 2/18, 11% in OC and 4/35, 11% in GC, P=0.003). The sensitivity, specificity, positive and negative predictive values of HER2 status at endoscopic biopsy were 56%, 93%, 63%, 91% respectively (weighted Kappa=0.504, P<0.0001). Five-year survival in OC HER2 positive negative was 100% and 36% (P=0.167) compared with 14% and 44% (P=0.0726) in JC and 50% and 46% (P=0.942) in GC respectively. Conclusions. Endoscopic biopsy had a high specificity and negative predictive value in determining HER2 status. Patients with JC had a significantly higher rate of HER2 overexpression and this was associated with a nonsignificant poorer survival trend. A larger study is needed to confirm these findings because of the implications for neoadjuvant and adjuvant chemotherapy regimens.
Cardiovascular Autonomic Response to Amlodipine in Primary Hypertension
Authors: Radjab Youssouf , Aboudrar Souad , Milouk Fatima Zahra , Rkain Hanan , EL Bakkali Mustapha , Dakka Taoufiq , Coghlan Leslie , Benjelloun Halima
Published: July 2012

Sympathetic hyperactivity may be involved in primary hypertension. The purpose of this study was to evaluate both sympathetic and vagal activity responses in patients receiving amlodipine as antihypertensive agent. Patients and Methods. This prospective study included a group of primary hypertensive patients (N=32, mean age 54.6±7.6 years). The cardiovascular autonomic tests performed in this group, before and after 3 months of daily oral administration of amlodipine, included deep breathing, hand-grip, and mental stress tests. Statistical analysis was done using the Student’s t-test. Results. Cardiovascular autonomic reflexes responses before and after 3 months of amlodipine oral administration were as follows: the mental stress test stimulation method produced a central alpha adrenergic response of 23.9±8.7% versus 11.2±2.0% (P<0.05), a central beta sympathetic response of 16.7±9.2% versus 10.4±1.3% (P<0.05), a blood pressure increase in response to hand grip test of 20.5±7.3% versus 10.7±2.4% (P<0.05), vagal response to deep breathing test was 21.2±6.5% versus 30.8±2.9%, (P<0.05). Conclusion. The results attest that amlodipine may have an anti-sympathetic effect.
Threads of Time
Authors: Annila Arto , Salthe Stanley
Published: July 2012

The concept of time’s arrow is examined using the principle of least action as given in its original non-Abelian form. When every entity of nature is considered to be composed of quantized actions, such an entity will change, either by absorbing quanta from surrounding actions or by emitting quanta to the surrounding actions. In natural processes, quanta disperse from high-energy density actions to low-energy density actions in quest of consuming free energy in least time. We propose that the flux of quanta embodies the flow of time, and therefore the irreversible consumption of free energy creates time’s arrow in a fundamental physical sense. The cosmological arrow of time results from universal processes that take place, most notably, in stars and other celestial systems, where matter, that is, bound actions, combusts to photons, that is, freely propagating actions. The biological arrow of time manifests itself in maturation processes where quanta absorb to emerging functional structures, leading eventually to aging processes where quanta, on balance, emit from disintegrating organs. Mathematical analysis of an evolutionary equation of motion, given in general terms of a spontaneous symmetry breaking process of actions, reveals the reason why future paths—and the future itself—remain inherently intractable.
Experimental Study of Laser-Induced Brass and Copper Plasma for Spectroscopic Applications
Authors: Gojani Ardian B.
Published: July 2012

This paper presents time-resolved and space-integrated laser-induced breakdown spectroscopic (LIBS) analysis of copper and brass plasma. It was observed that copper emission is very strong during the first hundred nanoseconds of the plasma, but then some lines (e.g., at 327.4 nm) decrease in intensity, while others (e.g., 521.8 nm) slightly increase. Zinc lines, on the other hand, did not decrease significantly in intensity even two microseconds after ablation, but they became narrower due to the decrease of the density of free electrons. Copper line intensities showed the same characteristics regardless whether the plasma was created in a metallic copper or brass sample. Assuming local thermodynamic equilibrium, plasma temperature, and electron density is obtained from Boltzmann plot and Lorentzian profile fitting, respectively. The effect of subsequent irradiation on the same spot was investigated, and the number of necessary shots for surface cleaning was determined.
A Study of Non-Euclidean s-Topology
Authors: Agrawal Gunjan , Shrivastava Sampada
Published: July 2012

The present paper focuses on the characterization of compact sets of Minkowski space with a non-Euclidean -topology which is defined in terms of Lorentz metric. As an application of this study, it is proved that the 2-dimensional Minkowski space with -topology is not simply connected. Also, it is obtained that the -dimensional Minkowski space with -topology is separable, first countable, path-connected, nonregular, nonmetrizable, nonsecond countable, noncompact, and non-Lindelöf.
Steroid-Induced Diabetes: Is It Just Unmasking of Type 2 Diabetes?
Authors: Simmons Lisa R. , Molyneaux Lynda , Yue Dennis K. , Chua Elizabeth L.
Published: July 2012

Aims. We compared the demographic profile and clinical characteristics of individuals with new onset steroid-induced diabetes (NOSID) to Type 2 diabetes (T2DM) patients with and without steroid treatment. Methods. The demographic profile and clinical characteristics of 60 individuals who developed NOSID were examined and matched to 60 type 2 diabetes patients receiving steroid therapy (T2DM+S) and 360 diabetic patients not on steroids (T2DM) for age, duration of diabetes, HbA1c, gender, and ethnicity. Results. Patients who developed NOSID had less family history of diabetes (P≤0.05) and were less overweight (P≤0.02). NOSID was more commonly treated with insulin. Despite a matching duration of diabetes and glycaemic control, significantly less retinopathy was found in the group of patients with NOSID (P<0.03). Conclusions. It appears that steroid treatment primarily precipitated diabetes in a group of individuals otherwise less affected by risk factors of diabetes at that point in time, rather than just opportunistically unmasking preexisting diabetes. Furthermore, the absence of retinopathy suggests that patients with NOSID had not been exposed to long periods of hyperglycaemia. However, the impact of the underlying conditions necessitating steroid treatment and concomitant medications such as immunosuppressants on diabetes development remain to be defined.
Urinary Bisphenol A Levels and Measures of Obesity: Results from the National Health and Nutrition Examination Survey 2003–2008
Authors: Shankar Anoop , Teppala Srinivas , Sabanayagam Charumathi
Published: July 2012

Bisphenol A (BPA) is a widely used chemical. We examined the association between urinary BPA levels and obesity in the National Health and Nutritional Examination Survey (NHANES) 2003–2008. The main outcome of interest was obesity defined as (1) body mass index (BMI) ≥ 30 Kg/m2 and (2) waist circumference (WC) ≥ 102 cm in men and ≥ 88 cm in women. Urinary BPA levels were examined in quartiles. Overall, we observed a positive association between increasing levels of urinary BPA and both measures of obesity, independent of potential confounding factors including, smoking, alcohol consumption, and serum cholesterol levels. Compared to quartile 1 (referent), the multivariate-adjusted odds ratio (95% confidence interval) associated with quartile 4 for BMI-based obesity was 1.69 (1.30–2.20); P-trend < 0.0001 and for WC-based obesity was 1.59 (1.21–2.09); P-trend = 0.0009. This association between BPA and both measures of obesity was consistently present across gender and race-ethnic groups (all P-trend < 0.05). Elevated levels of urinary BPA are associated with measures of obesity independent of traditional risk factors. This association is consistently present across gender and race-ethnic groups. Future prospective studies are needed to confirm or disprove this finding.
The Insulin-Like Growth Factor System and Nutritional Assessment
Authors: Livingstone Callum
Published: July 2012

Over recent years there has been considerable interest in the role of the insulin-like growth factor (IGF) system in health and disease. It has long been known to be dysregulated in states of under- and overnutrition, serum IGF-I levels falling in malnourished patients and responding promptly to nutritional support. More recently, other proteins in this system have been observed to be dysregulated in both malnutrition and obesity. Currently no biochemical marker is sufficiently specific for use in screening for malnutrition, but levels may be valuable in providing information on nutritional status and in monitoring of nutritional support. All have limitations as nutritional markers in that their serum levels are influenced by factors other than nutritional status, most importantly the acute phase response (APR). Levels should be interpreted along with clinical findings and the results of other investigations such as C-reactive protein (CRP). This paper reviews data supporting the use of proteins of the IGF system as nutritional markers.
Exclusive 1,2‐Aryl Shift in Platinum(II) Chloride‐Catalyzed Cyclization of 1‐(Indol‐2‐yl)‐2,3‐allenols
Authors: Kong Wangqing , Qiu Youai , Zhang Xue , Fu Chunling , Ma Shengming
Published: July 2012

An efficient cyclization of 1‐(indole‐2‐yl)‐2,3‐allenols in the presence of platinum(II) chloride leading to polysubstituted carbazoles via 1,2‐methyl or an exclusive 1,2‐aryl migration of the metal‐carbene intermediate was observed. The reaction proceeds via the intermediacy of a metal carbene intermediate, which induces the carbon‐carbon bond cleavage via 1,2‐migration to afford the products.
A Three‐Enzyme System Involving an Ene‐Reductase for Generating Valuable Chiral Building Blocks
Authors: Mangan David , Miskelly Iain , Moody Thomas S.
Published: July 2012

The use of ene‐reductase (ERED) enzymes for the asymmetric reduction of olefins offers a green, renewable alternative to metal‐catalysed asymmetric reduction. We report herein the first example of an ERED‐catalysed enantiospecific reduction carried out at large scale using a carbonyl reductase (CRED) enzyme in the cofactor recycle. This reaction has been paired with a hydrolase‐mediated regioselective ester hydrolysis to generate a valuable chiral building block using a straightforward one‐pot process.
Regio‐ and Stereoselective Hydroxylation of Optically Active α‐Ionone Enantiomers by Engineered Cytochrome P450 BM3 Mutants
Authors: Venkataraman Harini , Beer Stephanie B. A. de , Geerke Daan P. , Vermeulen Nico P. E. , Commandeur Jan N. M.
Published: July 2012

The selective hydroxylation of an unactivated CH bond is a crucial step in the synthesis of fine chemicals such as hydroxylated terpenoids. In the present study, the ability of 40 cytochrome P450 BM3 mutants to perform the regio‐ and stereoselective hydroxylation of α‐ionone has been investigated. Based on their activity and selectivity to produce 3‐hydroxy‐α‐ionone from racemic α‐ionone, 6 BM3 mutants were selected. Out of these, 3 mutants (M01 A82W, M11 A82W and M11 V87I) showed high selectivity for trans‐3‐hydroxy‐α‐ionone formation while 3 other mutants (M11 L437N, M11 L437S and M11 L437T) formed almost equal amounts of both cis‐3‐hydroxy‐ and trans‐3‐hydroxy‐α‐ionone. Incubation with individual enantiomers showed that M11 L437N, M11 L437S and M11 L437T exhibited opposite stereoselectivity producing (3S,6S)‐hydroxy‐α‐ionone with the (6S)‐enantiomer and (3S,6R)‐hydroxy‐α‐ionone with the (6R)‐enantiomer. Thus for the first time, BM3 mutants that can selectively produce diastereomers of 3‐hydroxy‐α‐ionone (>90% de), with high turnover numbers and minimal secondary metabolism, have been identified. Docking studies have been performed to rationalize the basis of the experimentally observed selectivity. In conclusion, engineered P450 BM3s are promising biocatalysts for regio‐ and stereoselective production of hydroxylated α‐ionones for industrial applications.
Nitrile Reductase from Geobacillus kaustophilus: A Potential Catalyst for a New Nitrile Biotransformation Reaction
Authors: Wilding Birgit , Winkler Margit , Petschacher Barbara , Kratzer Regina , Glieder Anton , Klempier Norbert
Published: July 2012

The cloning, expression and characterization of a nitrile reductase (NRed) from the thermophile Geobacillus kaustophilus is reported. The enzyme shows a 12‐fold increase in activity in response to a temperature change from 25 °C to 65 °C. The substrate scope regarding its biocatalytic applicability was investigated by testing a range of common nitriles. The narrow substrate range observed for the wild‐type enzyme prompted the rational design of GkNRed active site mutants based on a previously published homology model from Bacillus subtilis. The activities of the mutants and the wild‐type enzyme were investigated in their structure‐function relationship regarding the natural substrate 7‐cyano‐7‐deazaguanine (preQ0) as well as a range of synthesized preQ0‐like substrate structures. A distinct dependence of the wild‐type enzyme activity on specific structural modifications of the natural substrate was observed. Two non‐natural nitriles derived from preQ0 could be reduced to their corresponding amino compounds.
Tetraflic Acid (1,1,2,2‐Tetrafluoroethanesulfonic Acid, HC2F4SO3H) and Gallium Tetraflate as Effective Catalysts in Organic Synthesis
Authors: Prakash G. K. Surya , Mathew Thomas , Panja Chiradeep , Kulkarni Aditya , Olah George A. , Harmer Mark A.
Published: July 2012

Tetraflic acid offers ample acidity for various organic reactions that require high acidity. Its gallium(III) salt is an efficient catalyst under mild condtions for synthetic transformations such as the ketonic Strecker reaction for the synthesis of fluorinated α‐amino nitriles and condensation–cyclzation reactions using suitable fluoro ketones and 1,2‐disubstituted benzenes for the direct preparation of 5‐membered or 6‐membered fluorinated heterocycles.
Modular Bifunctional Chiral Thioureas as Versatile Organocatalysts for Highly Enantioselective Aza‐Henry Reaction and Michael Addition
Authors: Li Hua , Zhang Xu , Shi Xin , Ji Nan , He Wei , Zhang Shengyong , Zhang Bangle
Published: July 2012

A series of new modular bifunctional chiral thiourea organocatalysts were synthesized from natural Cinchona alkaloids and amino acids, and their performance in the aza‐Henry reaction of nitroalkanes to imines, the Michael addition of acetylacetone to nitroolefins and the Michael addition of acetone to nitroolefins was investigated. Under the mild conditions, the important building blocks β‐nitro amines and γ‐nitro carbonyl compounds could be obtained in good yields (up to 95%) with excellent enantioselectivities (up to 99% ee) and diastereoselectivity (up to 17:1).
Rhodium‐Catalyzed Asymmetric 1,4‐Additions, in Water at Room Temperature, with In‐Flask Catalyst Recycling
Authors: Lipshutz Bruce H. , Isley Nicholas A. , Moser Ralph , Ghorai Subir , Leuser Helena , Taft Benjamin R.
Published: July 2012

Using the newly introduced designer surfactant polyethylene glycol ubiquinol sebacate (PQS), as the platform for micellar catalysis, non‐racemic BINAP has been covalently attached and rhodium(I) inserted to form PQS‐BINAP‐Rh. This species, the first example of a non‐racemically‐ligated transition metal catalyst‐tethered amphiphile, can be utilized for Rh‐catalyzed asymmetric conjugate addition reactions of arylboronic acids to acyclic and cyclic enones. These are performed in water at room temperature, while the catalyst can be recycled without its removal from water in the reaction vessel.
Oxy Effects on the Platinum‐Catalyzed Carbo‐ and Oxacyclizations of 2‐Oxiranyl‐1‐(1‐oxyalk‐2‐ynyl)benzenes
Authors: Chaudhuri Rupsha , Pawar Samir Kundlik , Pati Kamalkishore , Liu Rai‐Shung
Published: July 2012

We report new platinum‐catalyzed protocols for the synthesis of carbocycles and oxacycles from 2‐oxiranyl‐1‐(1‐oxyalk‐2‐ynyl)benzenes. For 1,2,2‐trisubstituted epoxides bearing an acyloxy group, their platinum‐catalyzed cyclizations proceed through an initial 1,3‐acyloxy shift, followed by an intramolecular attack of an allenyl acetate at the carbonyl group, ultimately giving 2‐naphthyl ketones through a selective 1,2‐alkyl shift. 1,1‐Disubstituted epoxides bearing a siloxy group undergo an oxacyclization to give bicyclic ketals with high diastereoselectivity.
First Metal‐ and Base‐Free Selective Oxidative Coupling of Thiols in Neat Ionic Liquids: NMR Probed “Ambiphilic” Character of Neutral [hmim]Br towards Atom‐Efficient Synthesis of Disulfides
Authors: Kumar Rajesh , Sharma Nandini , Sharma Upendra K. , Shard Amit , Sinha Arun K.
Published: July 2012

The selective oxidative coupling of thiols has been studied in several imidazolium‐based ionic liquids in the absence of any base/metal catalysts. Disulfides were obtained from the corresponding thiols in good to excellent yields in 1‐hexyl‐3‐methylimidazolium bromide ([hmim]Br). Furthermore, a 1H NMR‐based mechanistic study of the SS bond formation demonstrated the cooperative role of halide anion and imidazolium cation of [hmim]Br as an “ambiphile” – a character found to be imperative for the efficient syntheses of disulfides. The developed methodology is simple, selective and green that utilises molecular oxygen as an oxidant and produces water as the only by‐product.
Highly Active Multidentate Alkyne Metathesis Catalysts: Ligand‐Activity Relationship and Their Applications in Efficient Synthesis of Porphyrin‐Based Aryleneethynylene Polymers
Authors: Jyothish Kuthanapillil , Wang Qi , Zhang Wei
Published: July 2012

A series of tris(arylmethyl)ammonium‐coordinated molybdenum(VI) propylidyne catalysts was synthesized. Such N‐quarternized multidentate catalysts showed high robustness, strong resistance to small alkyne polymerization and significantly enhanced catalytic activity compared to their corresponding tris(arylmethyl)amine‐based analogues. The high activity of these new catalysts also enabled the efficient synthesis of ethynylene‐bridged porphyrin‐based arylene ethynylene polymers via alkyne metathesis, which represents a highly efficient, defect‐free, viable approach for the synthesis of this class of intriguing polymers.
Asymmetric Hydrogenation of N‐Arylimines Catalyzed by the Xyl‐Skewphos/DPEN‐Ruthenium(II) Complex
Authors: Arai Noriyoshi , Utsumi Noriyuki , Matsumoto Yuki , Murata Kunihiko , Tsutsumi Kunihiko , Ohkuma Takeshi
Published: July 2012

The new catalyst system of RuBr2[(S,S)‐xyl‐skewphos][(S,S)‐dpen] and potassium tert‐butoxide shows high reactivity and enantioselectivity in the hydrogenation of N‐arylimines [Xyl‐Skewphos=2,4‐bis(di‐3,5‐xylylphosphino)pentane, DPEN=1,2‐diphenylethylenediamine]. A range of imines derived from aromatic and heteroaromatic ketones as well as some ferrocenyl and vinylic imines are hydrogenated with a turnover number as high as 18,000 under 10–50 atm of hydrogen to afford the amine products in up to 99% enantiomeric excess. The reaction is applied to the synthesis of a chiral N‐arylamine, which is the synthetic intermediate of a biologically active compound. The mode of enantioselection is interpreted by using transition‐state models based on the X‐ray structure of the Xyl‐Skewphos/DPEN‐RuBr2 complex.
Catalytic Asymmetric Synthesis of 3‐Substituted Proline Derivatives by Using Phase‐Transfer‐Catalyzed Conjugate Addition
Authors: Liu Yan , Usui Asuka , Shirakawa Seiji , Maruoka Keiji
Published: July 2012

The catalytic enantio‐ and diastereoselective synthesis of trans‐3‐substituted proline derivatives has been accomplished by chiral phase‐transfer‐catalyzed asymmetric conjugate addition of N‐(diphenylmethylene)glycine ester to α,β‐unsaturated aldehydes. Various 3‐substituted prolines that contain aromatic, heteroaromatic, and alkyl groups were synthesized efficiently with good to high enantioselectivity. This synthetic method can be applied to the efficient enantioselective synthesis of core structures of L‐pyrrolysine and telaprevir, which are important biologically active compounds. The practicability of the method was demonstrated by a gram‐scale synthesis of a core structure of telaprevir.
Dioxygen Reactivity of Biomimetic Iron–Catecholate and Iron–o‐Aminophenolate Complexes of a Tris(2‐pyridylthio)methanido Ligand: Aromatic CC Bond Cleavage of Catecholate versus o‐Iminobenzosemiquinonate Radical Formation
Authors: Halder Partha , Paria Sayantan , Paine Tapan Kanti
Published: July 2012

An iron(III)–catecholate complex [L1FeIII(DBC)] (2) and an iron(II)–o‐aminophenolate complex [L1FeII(HAP)] (3; where L1=tris(2‐pyridylthio)methanido anion, DBC=dianionic 3,5‐di‐tert‐butylcatecholate, and HAP=monoanionic 4,6‐di‐tert‐butyl‐2‐aminophenolate) have been synthesised from an iron(II)–acetonitrile complex [L1FeII(CH3CN)2](ClO4) (1). Complex 2 reacts with dioxygen to oxidatively cleave the aromatic CC bond of DBC giving rise to selective extradiol cleavage products. Controlled chemical or electrochemical oxidation of 2, on the other hand, forms an iron(III)–semiquinone radical complex [L1FeIII(SQ)](PF6) (2ox‐PF6; SQ=3,5‐di‐tert‐butylsemiquinonate). The iron(II)–o‐aminophenolate complex (3) reacts with dioxygen to afford an iron(III)–o‐iminosemiquinonato radical complex [L1FeIII(ISQ)](ClO4) (3ox‐ClO4; ISQ=4,6‐di‐tert‐butyl‐o‐iminobenzosemiquinonato radical) via an iron(III)–o‐amidophenolate intermediate species. Structural characterisations of 1, 2, 2ox and 3ox reveal the presence of a strong ironcarbon bonding interaction in all the complexes. The bond parameters of 2ox and 3ox clearly establish the radical nature of catecholate‐ and o‐aminophenolate‐derived ligand, respectively. The effect of ironcarbon bonding interaction on the dioxygen reactivity of biomimetic iron–catecholate and iron–o‐aminophenolate complexes is discussed.
A Luminescent and Sublimable DyIII‐Based Single‐Molecule Magnet
Authors: Yi Xiaohui , Bernot Kevin , Pointillart Fabrice , Poneti Giordano , Calvez Guillaume , Daiguebonne Carole , Guillou Olivier , Sessoli Roberta
Published: July 2012

The reaction of [Ln(hfac)3]⋅2 H2O and pyridine‐N‐oxide (PyNO) leads to isostructural dimers of the formula [Ln(hfac)3(PyNO)]2 (Ln=Eu, Gd, Tb, Dy). The Dy derivative shows a remarkable single‐molecule magnet behavior with complex hysteresis at 1.4 K. The dynamics of the magnetization features are two relaxation regimes: a thermally activated one at high temperature (τ0=(5.62±0.4)×10−11 s and Δ=(167±1) K) and a quantum tunneling regime at low temperature with a tunneling frequency of 0.42 Hz. The analysis of the Gd derivative evidences intradimer antiferromagnetic interactions (J=(−0.034±0.001) cm−1). Moreover, the Eu, Tb, and Dy derivatives are luminescent with quantum yield of 51, 53, and 0.1 %, respectively. The thermal investigation of [Dy(hfac)3(PyNO)]2 shows that the dimers can be sublimated intact, suggesting their possible exploit as active materials for surface‐confined nanostructures to be investigated by fluorimetry methods.
Anion Sensing in Aqueous Media by Photo‐active Transition‐Metal Bipyridyl Rotaxanes
Authors: Hancock Laura M. , Marchi Enrico , Ceroni Paola , Beer Paul D.
Published: July 2012

A chloride anion templation methodology is utilized in the construction of novel transition‐metal rhenium(I) and ruthenium(II) bipyridyl appended [2]rotaxanes. 1H NMR spectroscopic titrations reveal the ability of the rotaxanes to selectively bind chloride over the more basic oxoanions, with the ruthenium(II) bipyridyl appended rotaxane strongly binding chloride in 30 % water. Photophysical investigations demonstrate the ability of the rotaxanes to sense anions in aqueous media, with chloride being selectively complexed, in general agreement with NMR spectroscopy determined anion binding data.
TMBB-DB: a transmembrane β-barrel proteome database
Authors: Freeman Thomas C. , Wimley William C.
Published: July 2012

Motivation: We previously reported the development of a highly accurate statistical algorithm for identifying β-barrel outer membrane proteins or transmembrane β-barrels (TMBBs), from genomic sequence data of Gram-negative bacteria (Freeman,T.C. and Wimley,W.C. (2010) Bioinformatics, 26, 1965–1974). We have now applied this identification algorithm to all available Gram-negative bacterial genomes (over 600 chromosomes) and have constructed a publicly available, searchable, up-to-date, database of all proteins in these genomes.

Results: For each protein in the database, there is information on (i) β-barrel membrane protein probability for identification of β-barrels, (ii) β-strand and β-hairpin propensity for structure and topology prediction, (iii) signal sequence score because most TMBBs are secreted through the inner membrane translocon and, thus, have a signal sequence, and (iv) transmembrane α-helix predictions, for reducing false positive predictions. This information is sufficient for the accurate identification of most β-barrel membrane proteins in these genomes. In the database there are nearly 50 000 predicted TMBBs (out of 1.9 million total putative proteins). Of those, more than 15 000 are ‘hypothetical’ or ‘putative’ proteins, not previously identified as TMBBs. This wealth of genomic information is not available anywhere else.

Availability: The TMBB genomic database is available at http://beta-barrel.tulane.edu/.

Contact:  wwimley@tulane.edu
TAK1 contributes to the enhanced responsiveness of LTB4-treated neutrophils to Toll-like receptor ligands
Authors: Gaudreault Éric , Paquet-Bouchard Carine , Fiola Stéphanie , Le Bel Manon , Lacerte Patricia , Shio Marina Tiemi , Olivier Martin , Gosselin Jean
Published: July 2012

Pattern-recognition receptors such as Toll-like receptors (TLRs) are essential sensors implicated in the early and efficient innate immune response against pathogens. We have previously demonstrated that leukotriene B 4 (LTB 4 ) has the capacity to enhance leukocyte responses to TLR9 ligands and to control viral infection. In this report, we provide evidence that LTB 4 treatment of human neutrophils leads to a potentiation in proinflammatory cytokine secretion induced by various myeloid differentiation factor 88-dependent TLR agonists. LTB 4 failed to enhance TLR mRNA levels as well as expression of TLR2 and TLR4 receptors, suggesting that LTB 4 acts through intracellular mechanism(s) to potentiate neutrophil responses to TLR ligands. We found that while IRAK can be activated by LTB 4 , this process is dispensable to LTB 4 to potentiate neutrophil responses to TLR ligands since pretreatment of neutrophils with IRAK1/4 inhibitor did not affect its potentiating effects. However, our data clearly show that LTB 4 treatment of neutrophils led to the phosphorylation of downstream signaling molecules, TAK1 and p38, a process found essential to observe an increased secretion of cytokines by neutrophils activated with TLR ligands. Pretreatment of neutrophils with TAK1 or p38 kinase inhibitors strongly repressed the effect of LTB 4 on cytokine synthesis by neutrophils stimulated with LTA, LPS or CpG. The same pattern was observed in agonist-treated human embryonic kidney 293 cells transfected with TAK1-targeting siRNA where secretion of IL-8 was significantly reduced to basal levels. These results indicate that TAK1 and p38 kinases appear to be central in the ‘priming effect’ of LTB 4 on neutrophils to enhance response to TLR ligands.
Veillonella tobetsuensis sp. nov., an anaerobic, Gram-negative coccus isolated from human tongue biofilms
Authors: Mashima Izumi , Kamaguchi Arihide , Miyakawa Hiroshi , Nakazawa Futoshi
Published: July 2012

Four previously unknown, Gram-negative, anaerobic coccal strains were isolated from the tongue biofilm of healthy human adults (ages 22–29 years). The isolates displayed all phenotypic characteristics of the genus

Veillonella

. Comparative analysis of the 16S rRNA, dnaK and rpoB gene sequences indicated that the four strains were phylogenetically homogeneous and comprised a distinct novel lineage within the genus

Veillonella

. The production of major cellular fatty acids (C13 : 0 and C17 : 1ω8) was consistent with that of other members of the genus

Veillonella

. Based on these observations, strains B16T, A16, B4 and Y6 represent a novel species, for which the name Veillonella tobetsuensis sp. nov. is proposed, with the type strain B16T ( = JCM 17976T = ATCC BAA-2400T).
Alkalibacterium gilvum sp. nov., slightly halophilic and alkaliphilic lactic acid bacterium isolated from soft and semi-hard cheeses
Authors: Ishikawa Morio , Yamasato Kazuhide , Kodama Kayo , Yasuda Hinako , Matsuyama Mioko , Okamoto-Kainuma Akiko , Koizumi Yukimichi
Published: July 2012

Nine novel strains of halophilic and alkaliphilic lactic acid bacteria isolated from European soft and semi-hard cheeses by using a saline, alkaline medium (7 % NaCl, pH 9.5) were taxonomically characterized. The isolates were Gram-stain-positive, non-sporulating and non-motile. They lacked catalase and quinones. Under anaerobic cultivation conditions, lactate was produced fromd-glucose with the production of formate, acetate and ethanol with a molar ratio of approximately 2 : 1 : 1. Under aerobic cultivation conditions, acetate and lactate were produced fromd-glucose. The isolates were slightly halophilic, highly halotolerant and alkaliphilic. The optimum NaCl concentration for growth ranged between 2.0 % and 5.0 % (w/v), with a growth range of 0–1 % to 15–17.5 %. The optimum pH for growth ranged between 8.5 and 9.5, with a growth range of 7.0–7.5 to 9.5–10.0. Comparative sequence analysis of the 16S rRNA genes revealed that the isolates occupied a phylogenetic position within the genusAlkalibacterium, showing the highest sequence similarity (98.2 %) toAlkalibacterium kapiiT22-1-2T. The isolates constituted a single genomic species with DNA–DNA hybridization values of 79–100 % among the isolates and <29 % between the isolates and other members of the genusAlkalibacterium, from which the isolates were different in motility and flagellation, growth responses to NaCl concentrations and pH, and profiles of sugar fermentation. The DNA G+C contents were between 36.0 and 37.6 mol%. The cell-wall peptidoglycan was type A4β, Orn-d-Asp. The major components of cellular fatty acids were C14 : 0, C16 : 0and C16 : 1ω9c. Based on the phenotypic characteristics and genetic distinctness, the isolates are classified as a novel species within the genusAlkalibacterium, for which the nameAlkalibacterium gilvumsp. nov. is proposed. The type strain is 3AD-1T( = DSM 25751T = JCM 18271T).
Diddensiella caesifluorescens gen. nov., sp. nov., a riboflavin-producing yeast species of the family Trichomonascaceae
Authors: Péter Gábor , Dlauchy Dénes , Price Neil P. J. , Kurtzman Cletus P.
Published: July 2012

Four strains of a novel heterothallic yeast species were isolated from rotten wood collected in or near the Pilis Mountains in Hungary. The strains produced riboflavin in liquid culture. Analysis of gene sequences for the D1/D2 domains of the LSU nuclear rRNA, as well as analysis of concatenated gene sequences for the D1/D2 nuclear LSU rRNA, mitochondrial SSU rRNA and cytochrome oxidase II placed the novel species in a small clade including only two recognized species, Candida santjacobensis and Candida transvaalensis, in the family Trichomonascaceae. DNA sequence analyses demonstrated that the novel species was distinct from all currently recognized teleomorphic yeast genera. The name Diddensiella caesifluorescens gen nov., sp. nov. is proposed to accommodate the novel genus and species. The new genus proposed here can be recognized only from gene sequence analysis, because the characters of its asexual reproduction and ascospore formation are shared by several members of the genera Trichomonascus, Sugiyamaella and Spencermartinsiella. The type and isotype strains of D. caesifluorescens are NCAIM Y.01949T ( = NRRL Y-48781T = CBS 12613T) and NCAIM Y.01956I ( = NRRL Y-48782I = CBS 12614I), respectively. In view of their close relatedness to D. caesifluorescens, C. santjacobensis and C. transvaalensis are transferred to the genus Diddensiella as new combinations in accordance with changes in the International Code of Nomenclature for algae, fungi and plants.
Loktanella cinnabarina sp. nov., isolated from a deep subseafloor sediment, and emended description of the genus

Loktanella
Authors: Tsubouchi Taishi , Shimane Yasuhiro , Mori Kozue , Miyazaki Masayuki , Tame Akihiro , Uematsu Katsuyuki , Maruyama Tadashi , Hatada Yuji
Published: July 2012

A Gram-stain-negative, aerobic, heterotrophic and salt-tolerant bacterium, designated strain LL-001T, was isolated from a deep subseafloor sediment in Japanese waters. Cells were non-motile rods and colonies were smooth, convex, circular and vermilion. The conditions for growth were 15–35 °C, pH 5.5–7.5 and 1–8 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences confirmed that strain LL-001T belonged to the genus

Loktanella

within the family

Rhodobacteraceae

of the class

Alphaproteobacteria

. 16S rRNA gene sequence similarity between strain LL-001T and members of the genus

Loktanella

was 94.5–98.5 %; the highest sequence similarity was with

Loktanella hongkongensis

UST950701-009PT. DNA–DNA relatedness between strain LL-001T and

L. hongkongensis

UST950701-009PT was 41.5–43.6 %. The DNA G+C content of strain LL-001T was 69.3 mol%. On the basis of biochemical features and 16S rRNA gene sequence comparison, strain LL-001T is considered to represent a novel species of the genus

Loktanella

, for which the name Loktanella cinnabarina sp. nov. is proposed. The type strain is LL-001T ( = JCM 18161T = CECT 8072T). The description of the genus

Loktanella

is also emended.