bluuebunny/crossref_metadata_2025_split huggingface dataset:
Correction of eddy‐current distortions in diffusion tensor images using the known directions and strengths of diffusion gradients
Authors: Zhuang Jiancheng , Hrabe Jan , Kangarlu Alayar , Xu Dongrong , Bansal Ravi , Branch Craig A. , Peterson Bradley S. 
Published: October 2006

AbstractPurposeTo correct eddy‐current artifacts in diffusion tensor (DT) images without the need to obtain auxiliary scans for the sole purpose of correction.Materials and MethodsDT images are susceptible to distortions caused by eddy currents induced by large diffusion gradients. We propose a new postacquisition correction algorithm that does not require any auxiliary reference scans. It also avoids the problematic procedure of cross‐correlating images with significantly different contrasts. A linear model is used to describe the dependence of distortion parameters (translation, scaling, and shear) on the diffusion gradients. The model is solved numerically to provide an individual correction for every diffusion‐weighted (DW) image.ResultsThe assumptions of the linear model were successfully verified in a series of experiments on a silicon oil phantom. The correction obtained for this phantom was compared with correction obtained by a previously published method. The algorithm was then shown to markedly reduce eddy‐current distortions in DT images from human subjects.ConclusionThe proposed algorithm can accurately correct eddy‐current artifacts in DT images. Its principal advantages are that only images with comparable signals and contrasts are cross‐correlated, and no additional scans are required. J. Magn. Reson. Imaging 2006. © 2006 Wiley‐Liss, Inc.
Dual‐Syringe Reactive Electrospinning of Cross‐Linked Hyaluronic Acid Hydrogel Nanofibers for Tissue Engineering Applications
Authors: Ji Yuan , Ghosh Kaustabh , Li Bingquan , Sokolov Jonathan C. , Clark Richard A. F. , Rafailovich Miriam H. 
Published: October 2006

AbstractSummary: A facile fabrication of a cross‐linked hyaluronic acid (HA) hydrogel nanofibers by a reactive electrospinning method is described. A thiolated HA derivative, 3,3′‐dithiobis(propanoic dihydrazide)‐modified HA (HA‐DTPH), and poly(ethylene glycol) diacrylate (PEGDA) are selected as the cross‐linking system. The cross‐linking reaction occurs simultaneously during the electrospinning process using a dual‐syringe mixing technique. Poly(ethylene oxide) (PEO) is added into the spinning solution as a viscosity modifier to facilitate the fiber formation and is selectively removed with water after the electrospinning process. The nanofibrous structure of the electrospun HA scaffold is well preserved after hydration with an average fiber diameter of 110 nm. A cell morphology study on fibronectin (FN)‐adsorbed HA nanofibrous scaffolds shows that the NIH 3T3 fibroblasts migrate into the scaffold through the nanofibrous network, and demonstrate an elaborate three‐dimensional dendritic morphology within the scaffold, which reflects the dimensions of the electrospun HA nanofibers. These results suggest the application of electrospun HA nanofibrous scaffolds as a potential material for wound healing and tissue regeneration.Laser scanning confocal microscopy demonstrates that the NIH3T3 fibroblast develops an extended 3D dendritic morphology within the fibronectin‐adsorbed electrospun HA nanofibrous scaffold.magnified imageLaser scanning confocal microscopy demonstrates that the NIH3T3 fibroblast develops an extended 3D dendritic morphology within the fibronectin‐adsorbed electrospun HA nanofibrous scaffold.
Predicted function of the vaccinia virus G5R protein
Authors: Silva Melissa Da , Shen Ling , Tcherepanov Vasily , Watson Cristalle , Upton Chris 
Published: October 2006

Abstract
Motivation: Of the ∼200 proteins that have been identified for the vaccinia virus (VACV) genome, many are currently listed as having an unknown function, and seven of these are also found in all other poxvirus genomes that have been sequenced. The G5R protein of VACV is included in this list, and to date, very little is known about this essential and highly conserved protein. Conventional similarity searches of protein databases do not identify significantly similar proteins, and experimental approaches have been unsuccessful at determining protein function.
Results: Using HHsearch, a hidden Markov model (HMM) comparison search tool, the G5R protein was found to be similar to both human and archaeal flap endonucleases (FEN-1) with 96% probability. The G5R protein structure was subsequently successfully modeled using the Robetta protein structure prediction server with an archaeal FEN-1 as the template. The G5R model was then compared to the human FEN-1 crystal structure and was found to be structurally similar to human FEN-1 in both active site residues and DNA substrate binding regions.
Contact: cupton@uvic.ca
Supplementary information: Supplementary data are available at Bioinformatics online.
Moisturizing effect of cosmetic formulations containing Aloe vera extract in different concentrations assessed by skin bioengineering techniques
Authors: Dal'Belo Susi Elaine , Rigo Gaspar Lorena , Berardo Gonçalves Maia Campos Patrícia Maria 
Published: October 2006

Background/purpose: The polysaccharide‐rich composition of Aloe vera extracts (Aloe barbadensis Miller), often used in cosmetic formulations, may impart moisturizing properties to the product. The aim of this study was to evaluate the effect of cosmetic formulations containing different concentrations of freeze‐dried Aloe vera extract on skin hydration, after a single and a 1‐ and 2‐week period of application, by using skin bioengineering techniques.Methods: Stable formulations containing 5% (w/w) of a trilaureth‐4 phosphate‐based blend were supplemented with 0.10%, 0.25% or 0.50% (w/w) of freeze‐dried Aloe vera extract and applied to the volar forearm of 20 female subjects. Skin conditions in terms of the water content of the stratum corneum and of transepidermal water loss (TEWL) (CorneometerTM CM 825 and TewameterTM TM 210) were analysed before and after a single and 1‐ and 2‐week period of daily application.Results: After a single application, only formulations supplemented with 0.25% and 0.50% (w/w) of Aloe vera extract increased the water content of the stratum corneum, while after the 2‐week period application, all formulations containing the extract (0.10%, 0.25% and 0.50%) had the same effect, in both cases as compared with the vehicle. TEWL was not modified after a single and after 1‐ and 2‐week period of application, when compared with the vehicle.Conclusion: Our results show that freeze‐dried Aloe vera extract is a natural effective ingredient for improving skin hydration, possibly through a humectant mechanism. Consequently, it may be used in moisturizing cosmetic formulations and also as a complement in the treatment of dry skin.
Shear wave splitting changes associated with the 2001 volcanic eruption on Mt Etna
Authors: Bianco Francesca , Scarfı Luciano , Del Pezzo Edoardo , Patanè Domenico 
Published: October 2006

Summary
The time delays and polarizations of shear wave splitting above small earthquakes show variations before the 2001 July 17–August 9 2001 flank eruption on Mt Etna, Sicily. Normalized time delays, measured by singular value decomposition, show a systematic increase starting several days before the onset of the eruption. On several occasions before the eruption, the polarization directions of the shear waves at Station MNT, closest to the eruption, show 90°–flips where the faster and slower split shear waves exchange polarizations. The last 90°–flip being 5 days before the onset of the eruption. The time delays also exhibit a sudden decrease shortly before the start of the eruption suggesting the possible occurrence of a ‘relaxation’ phenomena, due to crack coalescence. This behaviour has many similarities to that observed before a number of earthquakes elsewhere.
Routine elastic staining assists detection of vascular invasion in colorectal cancer
Authors: Abdulkader M , Abdulla K , Rakha E , Kaye P 
Published: October 2006

Aim To determine the value of routine staining of colorectal cancer (CRC) specimens with elastic stains.Methods and results Four hundred and ninety‐eight cases of CRC were included. In 208 cases, vascular invasion (VI) was assessed using elastic stains [Elastic van Gieson or Elastin haematoxylin and eosin (H&E)] that were introduced as routine staining in CRC in our hospital. As a control, 290 cases in which VI was assessed solely on H&E staining were included. The site, stage and presence of vascular invasion were determined in both groups. The cost, time and workload resulting from the addition of these stains were also taken into account. The sensitivity of detection of VI in CRC was significantly improved after the introduction of these elastic stains in our routine practice (46.2% compared with 35.5% in the control group; P = 0.014). Particular improvement was noted in Dukes' stage A and B. We also noted that the net benefits gained from the introduction of these special stains outweighed the small extra cost and effort and, in addition, saved time for the reporting pathologists.Conclusion Routine elastic stains are very useful and practical in evaluation of VI status in CRC and we recommend implementing these stains in routine pathological practice to improve patient care.
External quality assurance for the laboratory diagnosis of Buruli ulcer disease in Ghana
Authors: Bretzel G. , Siegmund V. , Nitschke J. , Herbinger K. H. , Thompson R. , Fleischmann E. , Fleischer B. , Adjei O. 
Published: October 2006

SummaryObjective  To assure the quality of the laboratory diagnosis of Buruli ulcer disease; microscopy and PCR were subjected to external quality assurance (EQA).Methods  Slides were read by test laboratory staff, followed by blinded re‐reading by the controller. Parallel testing of PCR specimens was carried out at the local and external reference laboratory. Slides and PCR specimens with discordant results were subjected to a second reading/testing by the controller to determine the final result. For training purposes, slides and PCR specimens with discrepant results were subsequently re‐read/re‐tested under supervision at the test laboratory.Results  Microscopy. First reading: concordance rate 82.9%, discordance rate 17.1%, percentage false negatives 27.1% (sensitivity 72.9%), percentage false positives 10.1% (specificity 89.9%). Second reading: concordance rate 97.9%, discordance rate 2.1%, percentage false negatives 4.2% (sensitivity 95.8%), percentage false positives 0.6% (specificity 99.4%). PCR. First testing: concordance rate 87.9%, discordance rate 12.1%, percentage false negatives 8.2% (sensitivity 91.8%), percentage false positives 19.1% (specificity 80.9%). Second testing: concordance rate 96.2%, discordance rate 3.8%, percentage false negatives 4.7% (sensitivity 95.3%), percentage false‐positives 2.1% (specificity 97.9%).Conclusions  EQA identified deficiencies in the laboratory performance. Corrective action consisted in on‐site training and reduced the number of false‐negative and false‐positive microscopy and PCR results.Keywords  Buruli ulcer diagnosis , quality assurance , microscopy , PCR , Ghana
INCORPORATION OF ORTHO [32P]PHOSPHATE INTO THE SUBCELLULAR FRACTIONS OF DEVELOPING RAT BRAIN*
Authors: Abdel‐Latif Ata A. , ABood L. G. 
Published: October 2006

The refinement of techniques for the isolation of the cytoplasmic fractions of rat brain has now made it possible to study more accurately the biochemical development and turnover of the various subcellular elements of the neuron. A previous communication (Abdel‐Latif and Abood, 1964) described enzymic studies with cytoplasmic constituents prepared from embryonic and neonatal rat brains by the technique of density gradient centrifugation. It was the object of the present study to examine, with the aid of ortho [32P]phosphate, the formation and turnover of the phospholipids, phosphoproteins, and other phosphate‐containing compounds of the various subcellular components of the rat brain at various stages of development.While several investigations have dealt with the incorporation of32P1 into the phospholipids of rat brain (Ansell, 1960; Davison and Dobbing, 1960; Ansell and Spanner, 1959; Rossiter, 1957; and Dziewiatkowski and Bodian, 1950) none has dealt with the incorporation into the phospholipids and phosphoproteins of the various subfractions, and very little work has been done on the turnover of well‐defined phospholipids in the developing brain.
IONIC BASIS FOR THE DEPOLARIZATION OF CEREBRAL TISSUES BY EXCITATORY ACIDIC AMINO ACIDS
Authors: Bradford H. F. , McIlwain H. 
Published: October 2006

SUMMARY1. Membrane potentials were measured in samples of guinea pig cerebral cortex, before and after small localized additions of neutral solutions of a number of acidic amino acids.2. Prompt depolarization from resting membrane potentials of about −60 mv to values of −30 to −45 mv occurred in response to l‐aspartate, l‐cysteate, l‐glutamate, dl‐homocysteate and l‐α‐aminoadipate. Slower, smaller and less frequent depolarization followed N‐methyl‐d‐aspartate, N‐methyl‐dl‐aspartate and N‐ethyl‐D‐aspartate. No change was observed to follow N‐n‐propyl‐d‐aspartate, N‐methyl‐dl‐glutamate, β‐alanine or glutamine.3. The five amino acids which promptly depolarized, were found also to lower the phosphocreatine of cerebral tissues to which they were added during in vitro metabolism. They also increased the tissues’inorganic phosphate and in some cases diminished its acid‐labile nucleotide phosphate.4. The five amino acids which promptly depolarized increased the intracellular sodium of the tissues within a minute of their addition; two of the N‐alkylated acids also had this effect. None of the acids had a comparably prompt effect on the tissues’potassium content.5. Calculation from the data presented suggests (i) that glutamate increases fivefold the tissues’permeability to sodium relative to that to potassium; and (ii) that the additional sodium entering the tissue could accelerate its Na,K‐dependent adenosine triphosphatase sufficiently to account for the observed loss of energy‐rich phosphate and appearance of inorganic phosphate.
COMPARISON OF SPONTANEOUS LOSS OF CATECHOLAMINES AND ATP IN VITRO FROM ISOLATED BOVINE ADRENOMEDULLARY, VESICULAR GLAND, VAS DEFERENS AND SPLENIC NERVE GRANULES
Authors: Stjärne L. , Lishajko F. 
Published: October 2006

SUMMARYThe molar ratio catecholamines/ATP in the high speed sediment from homogenates of bovine adrenal medulla, vesicular gland, vas deferens and splenic nerve was relatively close to the‘equivalence ratio’of 4/1. On incubation in vitro the loss of amines and ATP from the medullary granules was slow and largely parallel. Thus the original amine/ATP ratio was maintained. The amine loss from the nerve granules occurred at a very high, and from the vesicular gland and vas deferens granules at an intermediate, rate. On the other hand, the decrease in ATP in these preparations was quite slow, leading to a marked change in the original amine/ATP ratio. These findings are regarded as further evidence of functional differences between granules derived from chromaffin cells and from sympathetic nerve tissue, and even between nerve granules from‘long’and 'short’noradrenergic neurons. The possible implications of these in vitro differences in amine and ATP release are discussed in relation to the mechanisms of amine release in vivo.
COMPARTMENTATION OF GLUTAMIC ACID METABOLISM IN BRAIN SLICES*
Authors: Berl S. , Nicklasi W. J. , Clarke D. D. 
Published: October 2006

Abstract—(1) Compartmentation of glutamate metabolism in brain cortex previously observed only in vivo, has now been demonstrated in vitro.This was shown by using [U‐14C]aspartate and [U‐14C]glutamate as tracer substrates.(2) Preparation and maintenance of the slices at 0° resulted in reversible inhibition of glutamine synthesis. Preincubation at 37° for 10 min or preparation of the slices at room temperature partially overcame this inhibition.(3) Transfer to fresh medium after preincubation had an added stimulatory effect on glutamine synthesis.(4) Incubation in high K+ medium (27 mm) altered the relative specific activity of glutamine.(5) The data are in keeping with the postulate of the existence of at least two different pools of citric acid cycle intermediates in the cerebral cortex.
THE EFFECTS OF 4‐HYDROXYBUTYRIC ACID ON THE BIOSYNTHESIS OF AMINO ACIDS IN THE CENTRAL NERVOUS SYSTEM
Authors: Godin Y. , Mark J. , Mandel P. 
Published: October 2006

Abstract—The effect of 4‐hydroxybutyrate (GHB) on cerebral glucose metabolism has been studied. GHB increases the glucose level, decreases the lactate concentration and diminishes the incorporation of glucose carbon into glutamic acid, glutamine, aspartic acid and GABA in the brain of the rat in a state of general anaesthesia. The data reported here suggest that GHB interferes in the metabolism of glucose in brain.
DEVELOPMENT OF TRANSPORT MECHANISMS FOR SULPHATE AND IODIDE IN IMMATURE CHOROID PLEXUS*
Authors: Robinson R. J. , Cutler R. W. P. , Lorenzo A. V. , Barlow C. F. 
Published: October 2006

Abstract—The time‐course of development of sulphate and iodide transport mechanisms in choroid plexus was studied by measuring uptake of [35S]sulphate and [125I]iodide from an incubating medium by isolated choroid plexuses of foetal and newborn rabbits and cats. Sulphate uptake by choroid plexus was poorly developed in rabbit foetuses just before term, but highly developed in newborn animals. Iodide uptake was already well developed in the most immature foetuses studied.
Measurement of acid monoamine metabolites in human and animal cerebrospinal fluid
Authors: Gerbode F. A. , Bowers M. B. 
Published: October 2006

SUMMARYTechniques for measuring 5‐hydroxyindolacetic acid (5‐HIAA) and homovanillic acid (HVA) have been modified to permit the use of smaller samples for measuring these acid monoamine metabolites in human and animal CSF. Levels of both HVA and 5‐HIAA were approximately three times as high in human ventricular CSF as in human lumbar CSF. Lumbar CSF levels of 5‐HIAA in neurologic patients were significantly higher than those in psychiatric patients. Values were obtained for HVA in dog cisternal CSF and for 5‐HIAA in dog, rabbit, and cat cisternal CSF.
A CHEMICAL METHOD FOR THE DETERMINATION OF ACETYLCHOLINE: ITS APPLICATION IN A STUDY OF PRESYNAPTIC RELEASE AND A CHOLINE ACETYLTRANSFERASE ASSAY1
Authors: FELLMAN J. H. 
Published: October 2006

Abstract— 1. A chemical method for the determination of acetylcholine has been devised based upon(a) The precipitation of acetylcholine out of solution as an iodine complex.(b) The absorption of the quaternary ester to a ‘carboxyl’ ion exchange resin column.(c) The hydrazinolysis of the acetylcholine to form acetyl hydrazide.(d) The formation of a fluorescent molecule with salicylaldehyde.2. The method was utilized to determine(a) If tetramethylammonium ions would release acetylcholine from the cat cervical synaptic ganglion.(b) The activity of enzyme choline acetyltransferase in rat brain.3. The observation that tetramethylammonium ions do release acetylcholine sustains the viability of the hypothesis that acetylcholine forms a primary acyl bond with its receptor.
PURINE AND PYRIMIDINE NUCLEOTIDES IN THE BRAIN OF NORMAL AND CONVULSANT RATS
Authors: Piccoli F. , Camarda R. , Bonavita V. 
Published: October 2006

Abstract— Purine and pyrimidine nucleotides were measured in the brain of normal and electroshocked rats after chromatographic separation on ion‐exchange resin of mono‐, di‐ and tri‐phosphorylated derivatives.CMP, IMP and NAD did not show any significant quantitative change. Adenine nucleotides showed an abrupt change followed by a rapid return to the control value. GTP was the only purine nucleotide exhibiting a relatively slow return to its starting concentration. The greatest percentage increase after electroshock was observed in UMP, which returned to its control value only after 5 min; UDPCoenzymes (i.e. UDPA plus UDPG) showed a relatively small drop during the development of the seizure and the slowest return to the base line; UTP showed a late transistory increase above the normal level after an initial drop associated with convulsant activity.Tritiated uridine was injected intracisternally to investigate the turnover of pyrimidine nucleotides. UTP showed the highest specific radioactivity at the earliest time, followed by UMP, UDPCoenzymes and CMP. It was found that convulsant activity is associated with dramatic changes in the specific radioactivity of pyrimidine nucleotides.
THE EFFECT OF BREATHING OXYGEN ON THE METABOLISM OF THE RAT BRAIN UNDER NORMAL AND ISCHAEMIC CONDITIONS
Authors: Gercken G. , Preuss H. 
Published: October 2006

Abstract—

Breathing oxygen (1 atm.) for 2 hr increased the glycogen content of the rat brain from 3·38 to 4·35 μmoles glucosyl residues/g wet wt. At the same time the glucose and lactate concentrations were significantly decreased.
Both under normal conditions and when breathing oxygen, the sum (glycogen + glucose) × 2 + lactate, with which the balance of carbohydrate breakdown and lactate formation was assessed, was 13·5 μmoles/g wet wt.
Oxygen breathing effected a significant decrease in this sum after an ischaemic period of 1–15 min. In the control group breathing normal air, the sum, after all periods of ischaemia, ranged from 98 to 106 per cent of the starting value.
An increased partial pressure of oxygen did not change the breakdown rate of the high‐energy phosphate compounds. This result was not consistent with an oxidation of the carbohydrates which were missing in the balance. It is probable that other metabolites, which were not tested for, accumulated.
0 We failed to find any indication of storage of oxygen which the ischaemic brain could use for oxidative energy production.
DISTRIBUTION AND PROPERTIES OF CDP‐DIGLYCERIDE:INOSITOL TRANSFERASE FROM BRAIN1
Authors: Benjamins Joyce A. , Agranoff B. W. 
Published: October 2006

Abstract—CDP‐diglyceride is converted to phosphatidyl inositol by several particulate subcellular fractions of guinea pig brain, with highest specific activity in the microsomal fraction. Optimal conditions with respect to pH, metal ion concentration, and substrate concentrations have been determined. The reaction was stimulated by the addition of bovine serum albumin and by Tween 80.Of several dl‐CDP‐diglycerides synthesized and used as substrates in a spectrophoto‐metric assay for the enzyme, dl‐CDP‐didecanoin was the most active.The enzyme showed a high selectivity for myo‐inositol. Of a number of compounds tested, only scyllo‐inosose and epi‐inosose served as substrates. Three inositol isomers and three myo‐inositol monophosphates inhibited the reaction slightly. The most potent inhibitor found was galactinol, a myo‐inositol galactoside.
LIGHT‐INDUCED ALTERATIONS IN RETINAL PYRUVATE AND HIGH‐ENERGY PHOSPHATES,IN VIVO
Authors: Lolley R. N. 
Published: October 2006

Abstract—The effect of illumination upon some metabolic substrates of frog retina was investigatedin vivo, using conditions of illumination for which electrophysiological correlates in the retina are well defined. Frogs were frozen immediately after illumination, the tissue was processed for quantitative histochemistry, and the compounds were measured fluorometrically.Levels of P‐creatine were lower in flash‐illuminated retinas than in either dark‐ or light‐adapted retinas. The high‐energy phosphates and pyruvate changed rapidly upon exposure to flashing light, then returned towards the original steady‐state level, with ATP preceding pyruvate and P‐creatine. ATP and P‐creatine were primarily concentrated in the bipolar and ganglion cell layers.The energy reserve of the retina was depleted by an enhanced rate of neural activityin vivo.Levels of P‐creatine and ATP decreased in only those cellular layers which initiate neural action potentials. These data suggest that the mechanisms of neural excitation are closely coupled to energy and glucose metabolism in the retina.