bluuebunny/crossref_metadata_2025 huggingface dataset:
Fatty acid and product selectivities of potato tuber lipid acyl hydrolase in esterification reactions with glycerol in organic media
Authors: Pinsirodom Praphan , Parkin Kirk L.
Published: May 2007

Fatty acid [FA; butanoic (C4); octanoic (C8); tetradecanoic (C14); and cis‐9,12‐octadecadienoic (C18:2) acids] reaction selectivity and the corresponding acyl profiles in differentially accumulating acylglycerol (AG) products (mono‐, di‐, and triacylglycerols; MAG, DAG, TAG, respectively) were evaluated for Celite™‐immobilized potato tuber lipid acyl hydrolase (LAH)‐mediated esterification reactions in isooctane at 35°C and water activity of 0.19. The ordinal pattern of FA selectivities was C8>C14>C18:2>C4, and the AG products accumulating were α‐MAG>DAG>β‐MAG>TAG. A dimensionless expression for fatty acid partitioning coefficient (FAPC) was contrived to represent the partitioning patterns of specific FA into specific AG pools on the basis of an equivalent extent of FA reaction. These FAPC values indicated that preferential partitioning of FA was as follows: C4 was preferentially partitioned into TAG, DAG, and β‐MAG; C8 was preferentially partitioned into DAG; C14 was preferentially partitioned into α,β‐MAG; C18:2 was preferentially partitioned into α,β‐MAG and TAG. These findings infer that the tendency for LAH‐mediated esterifications to accumulate MAG is based, in part, on a constraint in reactivity of α‐MAG of ≥10 acyl carbon groups to serve as acceptors for further esterification events. The general approach taken in this study may assist in identifying the discrete steps in assembling structured glycerides where different biocatalysts exhibit the greatest degree or control of reaction selectivity.
Alkylguanidine‐catalyzed heterogeneous transesterification of soybean oil
Authors: Sercheli Ricardo , Matheus Vargas Rogério , Schuchardt Ulf
Published: May 2007

Transesterification of soybean oil with methanol has been carried out in the presence of heterogenized alkylguanidines as catalysts. The alkylguanidines were anchored to modified polystyrene or siliceous MCM‐41, encapsulated in the supercages of zeolite Y, or entrapped in SiO2 sol‐gel matrices. The catalytic activity of these catalysts was compared with that of their homogeneous counterparts, showing that the yields of methyl esters obtained in the homogeneous phase can be obtained with the guanidines anchored to the supports after longer reaction times. The catalysts prepared by immobilization of alkylguanidines in microporous systems showed diffusion restrictions for the vegetable oil as well as the low stability of the inorganic framework.
Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry of Vernonia galamensis oil
Authors: Ayorinde Folahan O. , Elhilo Eisa , Hlongwane Caswell , Saeed Kamal A.
Published: May 2007

Matrix‐assisted laser desorption/ionization (MALDI) time‐of‐flight (TOF) mass spectrometry (MS) has been used to identify eight triacylglycerols (TAG) in Vernonia galamensis oil (VO). The TAG include trivernolin, divernoloylstearoylglycerol, divernoloyloleoylglycerol, vernoloyllinoleoylstearoylglycerol, vernoloyllinoleoyloleoylglycerol, and vernoloyldilinoleoylglycerol. Samples for the MALDI/TOF/MS analysis were prepared with alpha‐cyano‐4‐hydroxycinnamic acid (matrix) in an acetonitrile/tetrahydrofuran solvent system. A mol ratio of matrix/VO (44:1) gave reproducible composite spectra, resulting in resolutions greater than 8,000 and signal‐to‐noise ratios of above 1000 for the most abundant molecular species. 1,3‐Dioleoyl‐2‐stearoylglycerol and 1,2‐dioleoyl‐3‐palmitoylglycerol were used as calibration standards.
Apparent rapid fisheries escalation at a remote Caribbean island
Authors: MILLER M.W. , MCCLELLAN D.B. , WIENER J.W. , STOFFLE B.
Published: May 2007

Navassa Island is a small uninhabited island, approximately 60 km west of the south-west tip of Haiti (18°24′N, 75°00′W). Haiti laid claim to the island in 1804, however the USA claimed it under the Guano Act of 1856 and recently placed it under jurisdiction of the US Fish and Wildlife Service (USFWS). Remoteness from USFWS administration in Puerto Rico and disputed sovereignty by Haiti make enforcement of management impractical. Artisanal fishers from Haiti have frequented Navassa over the past several decades. Given the lack of current land-based development and limited transient land-based activity (for example salting fish and gear construction), Navassa provides a case study where fishing is largely isolated as the dominant human impact on coastal resources.
A population viability analysis (PVA) for Cabot's Tragopan (Tragopan caboti) in Wuyanling, south-east China
Authors: Zhang Yanyun , Zheng Guangmei
Published: May 2007

Understanding the status of fragmented populations and predicting their fate is an increasingly important part of bird conservation. Population viability analysis (PVA) can help in this process and is widely used for assessing the extinction risk faced by threatened species and for finding the key factors affecting population status and survival prospects. From 1982 to 2004, 14 scientists studied the population of the globally threatened Cabot's Tragopan Tragopan caboti in Wuyanling National Natural Reserve (WNNR), south-east China and collected life-history data on the population. Using VORTEX, we analysed the viability of the population in the reserve and this predicted that the population size will increase for the next 50 years and will then show a very slight decline for the next 50 years. The loss of heterozygosity is predicted to be 14%, suggesting that the population may not be viable in the long term. Sensitivity analyses showed that nest loss is the most important factor affecting population size and the survival probability of the population, which is supported by field studies. Though the new evidence shows that Cabot's Tragopan can build nests in spruce forest successfully, broad-leaf forest is still necessary for them for foraging, especially at some times of the year. The simulation also shows that the probability of survival and the size of the population will decrease markedly if the extent of suitable habitat is reduced even relatively slowly (such as 0.1% per year). Overall, we conclude that the PVA has provided very informative guidance to future management and research on Cabot's Tragopan at Wuyanling National Nature Reserve.
Historical emissions of black and organic carbon aerosol from energy‐related combustion, 1850–2000
Authors: Bond Tami C. , Bhardwaj Ekta , Dong Rong , Jogani Rahil , Jung Soonkyu , Roden Christoph , Streets David G. , Trautmann Nina M.
Published: May 2007

We present an emission inventory of primary black carbon (BC) and primary organic carbon (OC) aerosols from fossil fuel and biofuel combustion between 1850 and 2000. We reconstruct fossil fuel consumption and represent changes in technology on a national and sectoral basis. Our estimates rely on new estimates of biofuel consumption, and updated emission factors for old technologies. Emissions of black carbon increase almost linearly, totaling about 1000 Gg in 1850, 2200 Gg in 1900, 3000 Gg in 1950, and 4400 Gg in 2000. Primary organic carbon shows a similar pattern, with emissions of 4100 Gg, 5800 Gg, 6700 Gg, and 8700 Gg in 1850, 1900, 1950, and 2000, respectively. Biofuel is responsible for over half of BC emission until about 1890, and dominates energy‐related primary OC emission throughout the entire period. Coal contributes the greatest fraction of BC emission between 1880 and 1975, and is overtaken by emissions from biofuel around 1975, and by diesel engines around 1990. Previous work suggests a rapid rise in BC emissions between 1950 and 2000. This work supports a more gradual increase between 1950 and 2000, similar to the increase between 1850 and 1925; implementation of clean technology is a primary reason.
Low‐latitude hydrological cycle and rapid climate changes during the last deglaciation
Authors: Levi Camille , Labeyrie Laurent , Bassinot Franck , Guichard François , Cortijo Elsa , Waelbroeck Claire , Caillon Nicolas , Duprat Josette , de Garidel‐Thoron Thibault , Elderfield Harry
Published: May 2007

Sea surface temperature and oxygen isotopic records from two well‐dated Indian Ocean cores covering the last deglaciation show the occurrence of two periods of increased salinity along the route of warm surface water transport from the Indian to the Atlantic Ocean, one between 18 and 14.5 ka and the other during the Younger Dryas. Our results imply that during these periods, salt accumulated in the tropical Atlantic, creating favorable conditions for an abrupt resumption of the thermohaline circulation and abrupt northern hemisphere warming. Furthermore, we suggest that the observed pattern of millennial climate variability during the last glacial and deglaciation resulted from the interaction between the relatively slow rhythm of expansion and decay of the northern hemisphere ice sheets, and El Niño–Southern Oscillation variability, through changes in the position of the Intertropical Convergence Zone. This interaction generated an oscillator with millennial time response that operated at times of sufficient northern hemisphere ice sheets extent.
Enhanced deformation of limestone and sandstone in the presence of high fluids
Authors: Le Guen Y. , Renard F. , Hellmann R. , Brosse E. , Collombet M. , Tisserand D. , Gratier J.‐P.
Published: May 2007

Geological repositories subject to the injection of large amounts of anthropogenic carbon dioxide will undergo chemical and mechanical instabilities for which there are currently little experimental data. This study reports on experiments where low and high (8 MPa) aqueous fluids were injected into natural rock samples. The experiments were performed in flow‐through triaxial cells, where the vertical and confining stresses, temperature, and pressure and composition of the fluid were separately controlled and monitored. The axial vertical strains of two limestones and one sandstone were continuously measured during separate experiments for several months, with a strain rate resolution of 10−11 s−1. Fluids exiting the triaxial cells were continuously collected and their compositions analyzed. The high fluids induced an increase in strain rates of the limestones by up to a factor of 5, compared to the low fluids. Injection of high fluids into the sandstone resulted in deformation rates one order of magnitude smaller than the limestones. The creep accelerating effect of high fluids with respect to the limestones was mainly due to the acidification of the injected fluids, resulting in a significant increase in solubility and reaction kinetics of calcite. Compared to the limestones, the much weaker response of the sandstone was due to the much lower solubility and reactivity of quartz in high fluids. In general, all samples showed a positive correlation between fluid flow rate and strain rate. X‐ray tomography results revealed significant increases in porosity at the inlet portion of each core; the porosity increases were dependent on the original lithological structure and composition. The overall deformation of the samples is interpreted in terms of simultaneous dissolution reactions in pore spaces and intergranular pressure solution creep.
Thermal conductivity anisotropy of metasedimentary and igneous rocks
Authors: Davis Michael G. , Chapman David S. , Van Wagoner Thomas M. , Armstrong Phillip A.
Published: May 2007

Thermal conductivity anisotropy was determined for three sets of metasedimentary and igneous rocks from central Utah, USA. Most conductivity measurements were made in transient mode with a half‐space, line source instrument oriented in two orthogonal directions on a flat face cut perpendicular to bedding. One orientation of the probe yields thermal conductivity parallel to bedding (kpar) directly, the other orientation of the probe measures a product of conductivities parallel and perpendicular to bedding from which the perpendicular conductivity (kperp) is calculated. Some direct measurements of kpar and kperp were made on oriented cylindrical discs using a conventional divided bar device in steady state mode. Anisotropy is defined as kpar/kperp. Precambrian argillites from Big Cottonwood Canyon have anisotropy values from 0.8 to 2.1 with corresponding conductivity perpendicular to bedding of 2.0 to 6.2 W m−1 K−1. Anisotropy values for Price Canyon sedimentary samples are less than 1.2 with a mean of 1.04 although thermal conductivity perpendicular to bedding for the samples varied from 1.3 to 5.0 W m−1 K−1. The granitic rocks were found to be essentially isotropic with thermal conductivity perpendicular to bedding having a range of 2.2 to 3.2 W m−1 K−1 and a mean of 2.68 W m−1 K−1. The results confirm the observation by Deming [1994] that anisotropy is negligible for rocks having kperp greater than 4.0 W m−1 K−1 and generally increases for low conductivity metamorphic and clay‐rich rocks. There is little evidence, however, for his suggestion that thermal conductivity anisotropy of all rocks increases systematically to about 2.5 for low thermal conductivity rocks.
A new VLF/LF atmospheric noise model
Authors: Fieve S. , Portala P. , Bertel L.
Published: May 2007

Atmospheric noise, originating essentially from lightning discharges, is the main disturbance of VLF/LF telecommunications. This paper characterizes atmospheric noise in the 10–80 kHz range and proposes a new model: very accurate low‐frequency noise model (VALERIE). This model uses a new approach, which combines noise measurements with lightning data. The noise statistics were obtained from several years of measurements taken by the Délégation Générale de l'Armement (DGA)/Centre Technique des Systèmes Naval (CTSN) (Toulon, France) and the Space and Naval Warfare Systems (SPAWAR) (San Diego, California). Lightning data were provided by recent satellite observations made by NASA. A comparison of VALERIE predictions with measurements by cross validation showed an increase in accuracy compared to the current International Telecommunication Union (Geneva) model and a decreased average deviation. The model has been validated for the Atlantic area but may be extended as new measurements are collected.
Inhibition of acute nociceptive responses in rats after i.c.v. injection of Thr6‐bradykinin, isolated from the venom of the social wasp, Polybia occidentalis
Authors: Mortari M R , Cunha A O S , Carolino R O G , Coutinho‐Netto J , Tomaz J C , Lopes N P , Coimbra N C , dos Santos W F
Published: May 2007

Background and purpose:

In this work, a neuroactive peptide from the venom of the neotropical wasp Polybia occidentalis was isolated and its anti‐nociceptive effects were characterized in well‐established pain induction models.

Experimental approach:

Wasp venom was analysed by reverse‐phase HPLC and fractions screened for anti‐nociceptive activity. The structure of the most active fraction was identified by electron‐spray mass spectrometry (ESI‐MS/MS) and it was further assessed in two tests of anti‐nociceptive activity in rats: the hot plate and tail flick tests.

Key Results:

The most active fraction contained a peptide whose structure was Arg‐Pro‐Pro‐Gly‐Phe‐Thr‐Pro‐Phe‐Arg‐OH, which corresponds to that of Thr6‐BK, a bradykinin analogue. This peptide was given by i.c.v. injection to rats. In the tail flick test, Thr6‐BK induced anti‐nociceptive effects, approximately twice as potent as either morphine or bradykinin also given i.c.v. The anti‐nociceptive activity of Thr6‐BK peaked at 30 min after injection and persisted for 2 h, longer than bradykinin. The primary mode of action of Thr6‐BK involved the activation of B2 bradykinin receptors, as anti‐nociceptive effects of Thr6‐BK were antagonized by a selective B2 receptor antagonist.

Conclusions and implications:

Our data indicate that Thr6‐BK acts through B2 bradykinin receptors in the mammalian CNS, evoking antinociceptive behaviour. This activity is remarkably different from that of bradykinin, despite the structural similarities between both peptides. In addition, due to the increased metabolic stability of Thr6‐BK, relative to that of bradykinin, this peptide could provide a novel tool in the investigation of kinin pathways involved with pain.

British Journal of Pharmacology (2007) 151, 860–869; doi:10.1038/sj.bjp.0707275
Molecular expression and pharmacological identification of a role for Kv7 channels in murine vascular reactivity
Authors: Yeung S Y M , Pucovský V , Moffatt J D , Saldanha L , Schwake M , Ohya S , Greenwood I A
Published: May 2007

Background and purpose:

This study represents a novel characterisation ofKCNQ‐encoded potassium channels in the vasculature using a variety of pharmacological and molecular tools to determine their role in contractility.

Experimental approach:

Reverse transcriptase polymerase chain reaction (RT‐PCR) experiments were undertaken on RNA isolated from mouse aorta, carotid artery, femoral artery and mesenteric artery using primers specific for all knownKCNQgenes. RNA isolated from mouse heart and brain were used as positive controls. Pharmacological experiments were undertaken on segments from the same blood vessels to determine channel functionality. Immunocytochemical experiments were performed on isolated myocytes from thoracic aorta.

Key results:

All blood vessels expressedKCNQ1,4and5with hitherto ‘neuronal’KCNQ4being, surprisingly, the most abundant. The correlated proteins Kv7.1, Kv7.4 and Kv7.5 were identified in the cell membranes of aortic myocytes by immunocytochemistry. Application of three compounds known to activate Kv7 channels, retigabine (2 –20 μM), flupirtine (20 μM) and meclofenamic acid (20 μM), relaxed vessels precontracted by phenylephrine or 1 mM 4‐aminopyridine but had no effect on contractions produced by 60 mM KCl or the Kv7 channel blocker XE991 (10 μM). All vessels tested contracted upon application of the Kv7 channel blockers XE991 and linopirdine (0.1‐10 μM).

Conclusions and implications:

Murine blood vessels exhibit a distinctiveKCNQexpression profile with ‘neuronal’KCNQ4dominating. The ion channels encoded byKCNQgenes have a crucial role in defining vascular reactivity as Kv7 channel blockers produced marked contractions whereas Kv7 channel activators were effective vasorelaxants.

British Journal of Pharmacology(2007)151, 758–770; doi:10.1038/sj.bjp.0707284
Characterization of spinal α‐adrenergic modulation of nociceptive transmission and hyperalgesia throughout postnatal development in rats
Authors: Walker S M , Fitzgerald M
Published: May 2007

Background and purpose:

The selective α2‐adrenergic agonist dexmedetomidine is used clinically for analgesia and sedation, but effects in early life are not well characterized. Investigation of age‐related effects of dexmedetomidine is important for evaluating responses to exogenously administered analgesics and provides insight into postnatal function of noradrenergic pathways.

Experimental Approach:

We examined effects of epidural dexmedetomidine in anaesthetized rat pups (3, 10 and 21 postnatal days) using a quantitative model of nociception and C‐fibre induced hyperalgesia. Electromyographic recordings of withdrawal responses to hindpaw mechanical stimuli measured effects of dexmedetomidine upon the baseline reflex and the response to mustard oil application on the hindpaw (primary hyperalgesia) or hindlimb (secondary hyperalgesia). In addition, we compared epidural with systemic administration, examined effects of spinal transection and evaluated heart rate changes following dexmedetomidine.

Key Results:

Epidural dexmedetomidine dose‐dependently prevented mustard oil‐induced hyperalgesia at all ages but dose requirements were lower in the youngest pups. Higher doses also suppressed the baseline nociceptive reflex when given epidurally, but had no effect when given systemically. Analgesic efficacy was the same for primary and secondary hyperalgesia, and was not diminished by spinal cord transection.

Conclusions and Implications:

Our laboratory studies predict that spinally mediated α2‐agonist analgesia would be effective throughout postnatal development, dose requirements would be lower in early life and selective anti‐hyperalgesic effects could be achieved with epidural administration at doses lower than associated with antinociceptive or cardiovascular effects. Clinical trials of α2agonists in neonates and infants should consider developmentally regulated changes.

British Journal of Pharmacology(2007)151, 1334–1342; doi:10.1038/sj.bjp.0707290
Combined pharmacological block of IKr and IKs increases short‐term QT interval variability and provokes torsades de pointes
Authors: Lengyel C , Varró A , Tábori K , Papp J G , Baczkó I
Published: May 2007

Background and purpose:

Assessing the proarrhythmic potential of compounds during drug development is essential. However, reliable prediction of drug‐induced torsades de pointes arrhythmia (TdP) remains elusive. Along with QT interval prolongation, assessment of the short‐term variability of the QT interval (STV(QT)) may be a good predictor of TdP. We investigated the relative importance of IKs and IKr block in development of TdP together with correlations between QTc interval, QT interval variability and incidence of TdP.

Experimental approach:

ECGs were recorded from conscious dogs and from anaesthetized rabbits given the IKr blocker dofetilide (DOF), the IKs blocker HMR‐1556 (HMR) and their combination, intravenously. PQ, RR and QT intervals were measured and QTc and short‐term variability of RR and QT intervals calculated.

Key results:

DOF increased QTc interval by 20% in dogs and 8% in rabbits. HMR increased QTc in dogs by 12 and 1.9% in rabbits. Combination of DOF+HMR prolonged QTc by 33% in dogs, by 16% in rabbits. DOF or HMR given alone in dogs or HMR given alone in rabbits induced no TdP. Incidence of TdP increased after DOF+HMR combinations in dogs (63%) and following HMR+DOF (82%) and DOF+HMR combinations (71%) in rabbits. STV(QT) markedly increased only after administration of DOF+HMR combinations in both dogs and rabbits.

Conclusion and implications:

STV(QT) was markedly increased by combined pharmacological block of IKr and IKs and may be a better predictor of subsequent TdP development than the measurement of QTc interval prolongation.

British Journal of Pharmacology (2007) 151, 941–951; doi:10.1038/sj.bjp.0707297
Treprostinil potentiates the positive inotropic effect of catecholamines in adult rat ventricular cardiomyocytes
Authors: Fontana M , Olschewski H , Olschewski A , Schlüter K‐D
Published: May 2007

Background and purpose:

Prostanoids have been shown to improve exercise tolerance, hemodynamics and quality of life in patients with pulmonary arterial hypertension (PAH). We investigated whether treprostinil exerts direct contractile effects on cardiomyocytes that may explain partly the beneficial effects of these drugs.

Experimental approach:

Ventricular cardiomyocytes from adult rats were paced at a constant frequency of 0.5 to 2.0 Hz and cell shortening was monitored via a cell edge detection system. Twitch amplitudes, expressed as percent cell shortening of the diastolic cell length, and maximal contraction velocity, relaxation velocity, time to peak of contraction and time to reach 50% of relaxation were analyzed.

Key results:

Treprostinil (0.15 – 15 ng ml−1) slightly increased contractile dynamics of cardiomyocytes at clinically relevant concentrations. However, the drug significantly improved cell shortening of cardiomyocytes in the presence of isoprenaline, a β‐adrenoceptor agonist. Treprostinil exerted this effect at all beating frequencies under investigation. Treprostinil mimicked this potentiating effect in a Langendorff preparation as well. The potentiating effect of treprostinil on isoprenaline‐dependent cell shortening was no longer seen after phosphodiesterase inhibition. Long‐term cultivation of cardiomyocytes with treprostinil did not modify load free cell shortening of these cells, but reduces the duration of contraction.

Conclusions and implications:

We conclude that the clinically used prostanoid treprostinil potentiates the positive inotropic effects of catecholamines in adult ventricular cardiomyocytes. This newly described effect may contribute to the beneficial clinical effects of prostanoids in patients with PAH.

British Journal of Pharmacology (2007) 151, 779–786; doi:10.1038/sj.bjp.0707300
Chemogenomic approaches to drug discovery: similar receptors bind similar ligands
Authors: Klabunde T
Published: May 2007

Within recent years, a paradigm shift from traditional receptor‐specific studies to a cross‐receptor view has taken place within pharmaceutical research to increase the efficiency of modern drug discovery. Receptors are no longer viewed as single entities but grouped into sets of related proteins or receptor families that are explored in a systematic manner. This interdisciplinary approach attempting to derive predictive links between the chemical structures of bioactive molecules and the receptors with which these molecules interact is referred to as chemogenomics. Insights from chemogenomics are used for the rational compilation of screening sets and for the rational design and synthesis of directed chemical libraries to accelerate drug discovery.

British Journal of Pharmacology (2007) 152, 5–7; doi:10.1038/sj.bjp.0707308
Therapeutic treatment with poly(ADP‐ribose) polymerase inhibitors attenuates the severity of acute pancreatitis and associated liver and lung injury
Authors: Mota R , Sánchez‐Bueno F , Berenguer‐Pina J J , Hernández‐Espinosa D , Parrilla P , Yélamos J
Published: May 2007

Background and purpose:

The mortality associated with acute pancreatitis (AP) is largely attributable to abnormalities that occur in distant organs and supportive care remains the only treatment for patients with these complications. Recently, prophylactic pharmacological blockade of poly(ADP‐ribose) polymerase (PARP) enzymes has been shown to attenuate the severity of the disease. However, the clinical relevance of PARP inhibitors administered after the onset of AP remains uncertain. The aim of the present study was to investigate the therapeutic effects of PARP inhibitors in established AP.

Experimental approach:

Mice were fed a choline/methionine‐deficient/ethionine‐supplemented (CMDE) diet to induce AP. PARP inhibitors were given at 36 h after the onset of CMDE diet. Severity of pancreatitis was assessed by measurements of serum amylase, lipase, IL‐1β and IL‐6, and histological grading. Serum hepatic enzymes, myeloperoxidase (MPO) activity and morphological changes were measured as indicators of hepatic insult. Lung injury was evaluated by MPO activity and morphological changes. Survival rates of mice were monitored for 7 days.

Key results:

CMDE diet administration resulted in a significant increase in serum amylase, lipase, IL‐1β, IL‐6, alanine aminotransferase and aspartate aminotranferase levels, indicating AP and associated liver injury. Analysis of the histopathological changes in pancreas, liver and lung revealed extensive tissue damage. Treatment of mice with PARP‐inhibitors after the onset of AP was associated with a reduction in the severity of AP and, accordingly, with a reduced mortality rate.

Conclusions and Implications:

Our results support the therapeutic application of PARP inhibitors in the treatment of established AP.

British Journal of Pharmacology (2007) 151, 998–1005; doi:10.1038/sj.bjp.0707310
The SkyMapper Telescope and The Southern Sky Survey
Authors: Keller S. C. , Schmidt B. P. , Bessell M. S. , Conroy P. G. , Francis P. , Granlund A. , Kowald E. , Oates A. P. , Martin-Jones T. , Preston T. , Tisserand P. , Vaccarella A. , Waterson M. F.
Published: May 2007

This paper presents the design and science goals for the SkyMapper telescope. SkyMapper is a 1.3-m telescope featuring a 5.7-square-degree field-of-view Cassegrain imager commissioned for the Australian National University's Research School of Astronomy and Astrophysics. It is located at Siding Spring Observatory, Coonabarabran, NSW, Australia and will see first light in late 2007.

The imager possesses 16 384 × 16 384 0.5-arcsec pixels. The primary scientific goal of the facility is to perform the Southern Sky Survey, a six-colour and multi-epoch (four-hour, one-day, one-week, one-month and one-year sampling) photometric survey of the southerly 2π sr to g ∼23 mag. The survey will provide photometry to better than 3% global accuracy and astrometry to better than 50 milliarcsec. Data will be supplied to the community as part of the Virtual Observatory effort. The survey will take five years to complete.
Microwave-Accelerated Solvent- and Catalyst-Free Synthesis of 4-Aminoaryl/alkyl-7-chloroquinolines and 2-Aminoaryl/alkylbenzothiazoles
Authors: Motiwala Hashim F. , Kumar Raj , Chakraborti Asit K.
Published: May 2007

An efficient synthesis of 4-aminoaryl/alkyl-7-chloroquinolines and 2-aminoaryl/alkylbenzothiazoles has been developed by microwave-accelerated regioselective aromatic nucleophilic substitution of 4,7-dichloroquinoline and 2-chlorobenzothiazole with aromatic and aliphatic amines under solvent-free conditions in the absence of any added protic or Lewis acid catalyst. Chemoselective reaction with the amino group in preference to the phenolic hydroxy group was observed. Thus, the treatment of 4,7-dichloroquinoline (1 equiv.) with a mixture of aniline (2 equiv.) and phenol (2 equiv.) afforded exclusive formation of 4-aminophenyl-7-chloroquinoline. When 4,7-dichloroquinoline (1 equiv.) was separately treated with 2-aminophenol (2 equiv.) and 4-aminophenol (2 equiv.), 4-(2′-hydroxyphenyl)-7-chloroquinoline and 4-(4′-hydroxyphenyl)-7-chloroquinoline, respectively, were formed.
Halogenation of Carbonyl Compounds by an Ionic Liquid, [AcMIm]X, and Ceric Ammonium Nitrate (CAN)
Authors: Ranu Brindaban C. , Adak Laksmikanta , Banerjee Subhash
Published: May 2007

An ionic liquid, acetylmethylimidazolium halide ([AcMIm]X), in combination with ceric ammonium nitrate promotes halogenations of a wide variety of ketones and 1,3-keto esters at the α-position. The ionic liquid acts here as reagent as well as reaction medium, and thus the reaction does not require any organic solvent or conventional halogenating agent. The reaction is completely arrested when the radical quencher TEMPO is used. A plausible radical mechanism is also suggested.
Block of CaV1.2 Channels by Gd3+ Reveals Preopening Transitions in the Selectivity Filter
Authors: Babich Olga , Reeves John , Shirokov Roman
Published: May 2007

Using the lanthanide gadolinium (Gd3+) as a Ca2+ replacing probe, we investigated the voltage dependence of pore blockage of CaV1.2 channels. Gd+3 reduces peak currents (tonic block) and accelerates decay of ionic current during depolarization (use-dependent block). Because diffusion of Gd3+ at concentrations used (<1 μM) is much slower than activation of the channel, the tonic effect is likely to be due to the blockage that occurred in closed channels before depolarization. We found that the dose–response curves for the two blocking effects of Gd3+ shifted in parallel for Ba2+, Sr2+, and Ca2+ currents through the wild-type channel, and for Ca2+ currents through the selectivity filter mutation EEQE that lowers the blocking potency of Gd3+. The correlation indicates that Gd3+ binding to the same site causes both tonic and use-dependent blocking effects. The apparent on-rate for the tonic block increases with the prepulse voltage in the range −60 to −45 mV, where significant gating current but no ionic current occurs. When plotted together against voltage, the on-rates of tonic block (−100 to −45 mV) and of use-dependent block (−40 to 40 mV) fall on a single sigmoid that parallels the voltage dependence of the gating charge. The on-rate of tonic block by Gd3+ decreases with concentration of Ba2+, indicating that the apparent affinity of the site to permeant ions is about 1 mM in closed channels. Therefore, we propose that at submicromolar concentrations, Gd3+ binds at the entry to the selectivity locus and that the affinity of the site for permeant ions decreases during preopening transitions of the channel.
A new Chinese specimen indicates that ‘protofeathers’ in the Early Cretaceous theropod dinosaur
Sinosauropteryx
are degraded collagen fibres
Authors: Lingham-Soliar Theagarten , Feduccia Alan , Wang Xiaolin
Published: May 2007

Alleged primitive feathers or protofeathers in the theropod dinosaur
Sinosauropteryx
have potentially profound implications concerning feather morphogenesis, evolution of flight, dinosaur physiology and perhaps even the origin of birds, yet their existence has never been adequately documented. We report on a new specimen of
Sinosauropteryx
which shows that the integumental structures proposed as protofeathers are the remains of structural fibres that provide toughness. The preservation in the proximal tail area reveals an architecture of closely associated bands of fibres parallel to the tail's long axis, which originate from the skin. In adjacent more exposed areas, the fibres are short, fragmented and disorganized. Fibres preserved dorsal to the neck and back and in the distal part of the tail are the remains of a stiffening system of a frill, peripheral to the body and extending from the head to the tip of the tail. These findings are confirmed in the holotype
Sinosauropteryx
and NIGP 127587. The fibres show a striking similarity to the structure and levels of organization of dermal collagen. The proposal that these fibres are protofeathers is dismissed.
Asymmetry in the time‐lapse seismic response to injection and depletion
Authors: Sayers Colin M.
Published: May 2007

Large changes in seismic reflection amplitude have been observed around injectors, and result from the decrease in elastic‐wave velocity due to the increase in pore pressure in the reservoir. In contrast, the velocity change resulting from the decrease in pore pressure in depleting reservoirs is observed to be smaller in magnitude. Elastic‐wave velocities in sandstones vary with stress due to the presence of stress‐sensitive grain boundaries within the rock. Grain‐boundary stiffness increases non‐linearly with increasing compressive stress, due to increased contact between opposing faces of the boundary. This results in a change in velocity due to a decrease in pore pressure that is smaller than the change in velocity caused by an increase in pore pressure, in agreement with time‐lapse seismic observations. The decrease in porosity resulting from depletion is not fully recovered upon re‐pressurization, and this leads to an additional steepening of the velocity vs. effective stress curve for injection relative to depletion. This difference is enhanced by any breakage of cement or weakening of grain contacts that may occur during depletion and by the reopening or formation of fractures or joints and dilation of grain boundaries that may occur during injection.
Radiopacity of glass ionomer materials
Authors: SKARTVEIT L. , HALSE A.
Published: May 2007

summary
To facilitate the detection of overhangs and defects adjacent to a filling, restorative materials should have a radiographic density higher than or at least similar to that of enamel. In the present study the density of 21 glass ionomer materials was measured and compared with the density of enamel, dentine, amalgam and aluminium. Most materials were more radiopaque than enamel, thereby satisfying the requirements as proposed by several investigators. The materials with lower density were mainly types intended for use in anterior teeth where the entire filling can more easily be examined clinically. They should not be used as a base under approximal fillings in order to avoid a false positive diagnosis of recurrent caries.
Tissue reactions to biodegradable and non‐degradable membranes placed transcutaneously in rats, observed longitudinally over a period of 4 weeks
Authors: GALGUT P. , WAITE I. , SMITHS R.
Published: May 2007

summary
The aim of this study was to observe the tissue responses to a number of membrane materials processed for use in guided tissue regeneration at different time periods. Non‐degradable Gore‐Tex° PTFE membrane and degradable polylactic acid (PLA) membranes were placed transcutaneously in surgical incisions made in the dorsum of rats. The tissue responses to these materials were observed histologically at 3 days, 1 week and 4 weeks after placement. A wide variation in the tissue responses to both materials was evident at each time period. These variations could not be attributed to different rates of healing over time, but rather to more complex factors. These factors may include differences in host responses between different animals, local factors pertaining to specific site variations, physical characteristics of the materials like surface texture, and contamination from the wound surface. Neither membrane material was found to be totally satisfactory. The PLA membranes were well tolerated by the tissues but they were unevenly absorbed within 2 weeks of placement. The Gore‐Tex PTFE membranes, however, were associated with prolonged acute inflammatory infiltrate throughout the duration of the study, indicating that they were less well tolerated by the tissues than the PLA materials. As the healing characteristics of tissues are complex and highly variable, and as neither the non‐degradable PTFE or degradable PLA membranes demonstrated ideal tissue responses, it is concluded that variations in clinical responses to these materials used in regeneration techniques must be anticipated.
Synergistic effect of malocclusion and oral parafunctions on craniomandibular dysfunction in children with and without unpleasant life events
Authors: VANDERAS A. P.
Published: May 2007

summary
An epidemiological study was conducted on 386 children aged 6–10, with and without unpleasant life events, to investigate the synergistic effect of malocclusion and oral parafunctions on cranio mandibular dysfunction. The results showed that the synergistic effect of certain occlusal factors and oral parafunctions was significantly correlated with clicking and symptoms of dysfunction in both groups and with TMJ and muscle tenderness in subjects without npleasant life events. In children with unpleasant life vents TMJ and muscle tenderness were not correlated with any combination of malocclusion and oral parafunction. The present study suggests that the synergistic effect of malocclusion and oral parafunctions is a ‘sufficient’ cause for development of clicking and symptoms of dysfunction in both groups and TMJ and muscle tenderness in subjects without unpleasant life events. Also, in children with unpleasant life events, other aetiologic factor(s) can be responsible for the development of TMJ and muscle tenderness.
The evaluation of masticatory function with low adhesive colour‐developing chewing gum
Authors: MATSUI Y. , OHNO K. , MICHI K. , HATA H. , YAMAGATA K. , OHTSUKA S.
Published: May 2007

summary
Many objective methods have been described to evaluate masticatory function. Recently, a new chewing gum system has been reported that utilizes a phloxine‐sodium bicarbonate reaction and measures a chromatic coordinate as a functional indicator. A low‐adhesive colour‐developing chewing gum has been developed by selecting an appropriate gum base. This study examined the applicability of the system and reproducibility of results in subjects with different dental states. Tests were performed on 15 natural dentate subjects and 15 complete denture wearers after determination of germane test conditions through a pilot study. The colour was measured by a*, one of the coordinates in the L*a*b* colour system. All subjects could perform the test. The coefficient of variation ranged from 1.87% to 7.90%, averaging 5.15% in the natural dentate subjects and from 1.5% to 17.9%, averaging 9.75% in the complete denture wearers. The 95% confidence interval of a* was 28.76 ± 1.76 in the natural dentate subjects and 10.05 ± 2.58 in the complete denture wearers. The results indicated that this material can be useful for both complete denture wearers and subjects with a natural dentition with adequate reproducibility.
Patterns of jaw muscle activity during voluntary chewing
Authors: PLESH O. , BISHOP B. , McCALL W.D.
Published: May 2007

summary
Mastication is controlled by central rhythm and burst generators, but whether this control is similar under automatic and voluntary chewing is not clear. Our first aim was to determine whether increased chewing frequency led to a proportional decrease in both the burst duration (the time of muscle activity) and the interburst interval (time of inactivity) of each muscle or to a minimal decrease in the burst duration and a substantial decrease in the interburst interval. Our second aim was to determine whether these two manifestations of control differed between the opening and closing muscles. Electromyograms from digastric, medial pterygoid, masseter and anterior temporalis muscles were obtained during gum chewing by five subjects at four frequencies. A nearly fourfold decrease in total cycle duratin (TCD) with increased chewing frequencies was accompanied by minimal changes in burst duration in the digastric muscle but proportional changes in the jaw closing muscles. The onset latency of the digastric muscle as a percentage of TCD decreased and became negative (i.e. occurred before opening started) as the TCD decreased. The onset latencies of the jaw closing muscles remained roughly 10.20% of the TCD for the three lower chewing frequencies. Control of the opening muscle appears to differ from control of the closing muscles
Failure of dental bridges. I. Age and sex of patients and distribution of replaced and abutment teeth
Authors: AL‐RAFEE M.A. , FAYYAD M.A.
Published: May 2007

summary
In this study, 156 dental bridges, constructed in 132 randomly selected patients were evaluated. There was no significant difference between the number of bridges placed in males and the number placed in females. However, the results revealed that the maxillary arch received more prostheses than the mandibular arch. The most‐frequently replaced teeth were the mandibular first molars and the least‐frequently replaced were mandibular canines. Maxillary second premolars, the mandibular second premolars and the mandibular second molars were the most frequent teeth used as abutments.
An in vitro microleakage study of a new multi‐purpose dental adhesive system
Authors: YAP A. , STOKES A.N. , PEARSON G.J.
Published: May 2007

summary
Despite the advances made in the field of adhesive dentistry, microleakage still remains an area of concern, as a secure seal to dentine and cementum still cannot be achieved with certainty. This project compared the effectiveness of a new adhesive, Scotchbond Multi‐Purpose Dental Adhesive System® (SBMP) with an established product, Gluma Bonding System® (Gluma) in preventing microleakage and the influence of storage, thermal and load cycling on microleakage patterns. In uncycled specimens, Gluma Bonding System had significantly less leakage (P < 001) at both occlusal and cervical margins. Thermocycling of composite restorations utilizing SBMP resulted in a significant decrease (P < 005) at the occlusal margins but had no effects on cervical leakage. Mechanical loading had no influence on leakage patterns either cervically or occlusally. Three months' storage and combined treatment resulted in a significant decrease in leakage (P < 005) at the occlusal margins.
Studies of changes in occlusion after the insertion of complete dentures. Part I*
Authors: UTZ K.‐H.
Published: May 2007

summary
The present study aims to investigate changes in the occlusion of complete dentures after their insertion. A total of 85 edentulous patients were provided with new complete dentures. Their individual hinge axes were determined using mechanical axiography and the upper finished dentures were transferred by facebows to Dentatus® articulators. The lower dentures were mounted according to an intraoral central bearing point (CBP) registration and equilibrated in terminal hinge position. An articulator specially modified for measurements in the condylar area was used. The differences between the positions of the condylar balls with CBP registration and those after equilibrating the occlusion were determined. On average, 19 days after insertion, 71 patients took part in a follow‐up examination. As in the first session, the terminal hinge position was registered with the CBP method using the apex of the Gothic arch. Thus, the positions of the condylar balls immediately after the new registration could be compared with those in equilibrated in‐tercuspation 3 weeks earlier. The differences were found to be 0–5 ± 0–4 mm (0.2–9 mm) in the three axes (sagittal, coronal and horizontal). They are thought to result from settling into the denture bearing tissues and also from neuromuscular adjustment of the masticatory system. Compulsory remounting of complete dentures after insertion is therefore recommended.
Alteration in the bite force and EMG activity with changes in the vertical dimension of edentulous subjects
Authors: MORIMOTO T. , ABEKURA H. , TOKUYAMA H. , HAMADA T.
Published: May 2007

summary
The bite force and EMG activity of jaw closing muscles were studied at seven different vertical jaw positions around the occlusal vertical dimension (OVD) in 10 edentulous subjects. When the masseteric EMG activity was maintained at constant values (40% and 20% of the maximum activity at the OVD), the bite force increased in proportion to increase of the vertical dimension. On the other hand, when the bite force was maintained at constant values (4 kg and 8 kg), the EMG activities of the jaw closing muscles decreased, with an increase of the vertical dimension. These results indicate that the OVD is not the position at which the most efficient exertion of the bite force is obtained.
Analysis of composition and structure of hard autopolymerizing reline resins
Authors: ARIMA T. , MURATA H. , HAMADA T.
Published: May 2007

summary
The authors investigated the composition and structure of six hard auto‐polymerizing reline resins. The chemical compositions, glass transition temperatures, molecular weights and particle size distributions of the powders, and the chemical compositions of the liquids were examined. The powder compositions were classified into three groups. The first group contained poly(methyl methacrylate). The second contained poly (ethyl methacrylate) and poly(methyl methacrylate/ethyl methacrylate) and the third contained poly(ethyl methacrylate). The average molecular weights of these powders was about 2 × 105. The indexes of molecular weight dispersion suggested that all powders contained polymers that had a narrow molecular weight distribution. The particle size distribution of these powders was classified into two groups. The first group was mainly in the range of 50–100 μm and the second mainly between 20 and 50 μm. The composition of the liquids was classified into three groups. The first group contained a monofunctional methacrylate monomer. The second contained a monofunctional methacrylate monomer and a plasticizer and the third contained monofunctional methacrylate monomers and cross‐linking agents. The results of this experiment showed the differences in composition among the products. This will be useful for examining the relationship between the composition and mechanical properties of hard autopolymerizing reline resins.
Retention force changes in implant‐supported titanium telescope crowns over long‐term use in vitro
Authors: BESIMO CH. , GRABER G. , FLÜHLER M.
Published: May 2007

summary
Titanium is used to fabricate spherical and bar attachments for overdentures on osseointegrated implants. This in vitro study investigated the long term effects of commercially pure titanium on the retention force of telescope crowns with conical interface. Combinations of various materials for the inner and outer crowns were tested. Telescope crowns of pure titanium showed retention force charac teristics comparable to telescope crowns fabricated conventionally in a precious alloy.