bluuebunny/crossref_metadata_2025 huggingface dataset:
Genomic organization, gene structure, and developmental expression of three Clustered otx genes in the sea anemone Nematostella vectensis
Authors: Mazza Maureen E. , Pang Kevin , Martindale Mark Q. , Finnerty John R.
Published: March 2007

Otx homeodomain transcription factors have been studied in a variety of eumetazoan animals where they have roles in anterior neural development, endomesoderm formation, and the formation of larval ciliated fields. Here, we describe the gene structure and developmental expression of three Otx loci in the starlet sea anemone, Nematostella vectensis (phylum Cnidaria; class Anthozoa). Nematostella's three Otx genes (OtxA, OtxB, and OtxC) are located in a compact genomic cluster spanning 63.6 kb. The homeodomains of all three Otx genes are highly similar to their bilaterian counterparts, but only OtxB exhibits the conserved WSP motif that is located downstream of the homeodomain in many Otx proteins. The genomic organization, in concert with phylogenetic analyses, indicates that two tandem duplications occurred in the lineage leading to Nematostella some time after the Cnidaria diverged from the Bilateria. In situ hybridization reveals that otx is initially expressed by invaginating mesendodermal cells in the gastrula. Later, each of the three otx paralogs is expressed in three discrete larval body regions: in the endoderm of the foot or physa, in an endodermal ring surrounding the pharynx, and in the ectoderm of the tentacles. These data suggest that a single otx locus had already acquired diverse developmental functions in the cnidarian‐bilaterian ancestor. Furthermore, following two gene duplications in the line leading to Nematostella, there have been only minor alterations in the spatiotemporal expression of the three Otx paralogs. However, the absence of a conserved protein domain in OtxA and OtxC suggests functional evolution of the protein itself. J. Exp. Zool. (Mol. Dev. Evol.) 308B:494–506, 2007. © 2007 Wiley‐Liss, Inc.
Fast “real time” imaging with different k‐space update strategies for interventional procedures
Authors: Busch Martin , Bornstedt Axel , Wendt Michael , Duerk Jeffrey L. , Lewin Jonathan S. , Grönemeyer Dietrich
Published: March 2007

Interventional procedures under MR guidance require the images to be acquired with a fast acquisition strategy, a rapid reconstruction algorithm for “real‐time” imaging (ie, high temporal resolution), acquisition of at least three adjacent slices to track a tool reliably, and high tissue contrast to ensure safe positioning of interventional devices. Often times, the field strength for interventional MR‐imaging units is limited by the open magnet design. This complicates the trade‐off between scan time and image quality, particularly when applied during low field interventional MRI procedures. To minimize the impact of some of these tradeoffs, a combination of keyhole techniques or modified k‐space trajectories, in conjunction with a fluoroscopic (ie, continuous acquisition) mode and a real time reconstruction, permits rapid imaging in a low field system using standard (speed optimized) reconstruction hardware and standard gradient electronics. The purpose of this study was to design and describe different keyhole strategies that can be used in a real time mode to increase the image frame rate by a factor of up to 16. By updating the entire raw data space with our strategies, even small changes of the object could be recognized. Our results using these new strategies on two commercially available open magnet MR‐imaging units (Siemens Magnetom Open 0.2T resistive magnet, Toshiba Access 0.064T permanent magnet) and a 1.5T superconductive solenoidal magnet design imager (Siemens SP) are presented to show the potential of these acquisition strategies in interventional MRI. Furthermore, these strategies may also be helpful for several other medical applications requiring high temporal resolution like contrast‐enhanced breast imaging or functional brain imaging.
MR‐guided biopsy using a T2‐weighted single‐shot Zoom Imaging sequence (Local Look technique)
Authors: Buecker Arno , Adam Gerhard , Neuerburg Joerg M. , Glowinski Arndt , van Vaals Joop J. , Guenther Rolf W.
Published: March 2007

The purpose of this study was to demonstrate the utility of a T2‐weighted single shot turbo spin‐echo technique — the so‐called “Local Look” (LoLo) and more recently renamed “Zoom Imaging” technique — for MR‐guided percutaneous interventions. We performed 28 procedures on 22 patients using a 1.5‐T system for MR guidance. All procedures were controlled with the LoLo technique, which acquires T2‐weighted images in 600 msec. This is achieved by using a small field of view (250 × 125 mm) along with a maximum echo train length, the so‐called “single shot method.” To prevent backfolding artifacts, the 90° and 180° pulses were oriented orthogonally to each other. Because signal is created only in the region in which the pulses overlap, no backfolding can occur from outside this area. Half of the biopsies were additionally monitored using a fast gradient‐echo sequence, which was compared with the LoLo technique. All of the procedures were technically successful, and there were no procedural complications. The LoLo technique produced images that had good contrast between the lesion and the needle artifact, and the artifact size was smaller than that produced by the gradient‐echo technique. Subjective judgment of the ability to accurately delineate the needle tip indicated that the LoLo technique was either superior to (73%) or equal to (27%) the gradient‐echo sequence in all cases. The LoLo technique is an accurate and effective method for MR guidance of percutaneous procedures, because it shows good lesion contrast and small needle artifacts. The additional use of a gradient‐echo sequence during the procedure planning stage is advisable in more difficult cases, particularly when adjacent blood vessels are a concern. Monitoring of the needle tip is best performed with the LoLo technique.
Gradient echo MRI for measurement of the pulmonary autograft diameter after transplantation to the aortic root: Validation and comparison with ultrasound
Authors: Hokken Raymond B. , de Bruin Hein G. , Taams Meindert A. , Bogers Ad J. J. C. , van Herwerden Lex A. , Roelandt Jos R. T. C. , Bos Egbert , Oudkerk Matthijs
Published: March 2007

The purpose of this study was to s the value of MRI for measurement of pulmonary autograft diameters after transplantation to the aortic root in adults. Thirty‐eight adults underwent this operation. MRI and trans‐esophageal echocardiography (TEE) were performed in 30 and 27 patients, respectively, after a mean follow‐up period of 2.8 years. For internal validation of MRI, measurements at the diastolic short and long axes of the sinus level were used. Pulmonary autograft diameters were measured and compared with MRI and TEE at five different levels: the subannular region (1), an‐nulus (2), sinus (3), sinotubular junction (4), and the distal part of the autograft (5). The correlation coefficient (r2) between long‐ and short‐axis measurements for corresponding sinuses was .97. Diameters obtained with MRI were 1 to 3 mm larger than those obtained with TEE (P < .05), except for the annulus at systole (P > .3). Cine gradient echo MRI is an appropriate technique to evaluate pulmonary autograft diameters during follow‐up. Concordance with TEE was good, apart from a systematic difference of ≈︁ 2 mm.
Optimized outer volume suppression for single‐shot fast spin‐echo cardiac imaging
Authors: Le Roux Patrick , Gilles Raymond J. , McKinnon Graeme C. , Carlier Pierre G.
Published: March 2007

Among the ultrafast MRI techniques, the single‐shot fast spin‐echo sequence offers a robust alternative to echo planar imaging, essentially because of a much reduced sensitivity to B0 inhomogeneity. This property is particularly appealing in situations in which B0 in‐homogeneities can be severe and difficult to correct, such as in cardiac imaging. With single‐shot cardiac imaging, however, achieving high resolution over the necessarily large field of views without introducing back‐folding artifacts is problematic. One option is to use multishot sequences. However, then issues related to cardiac gating arise. Another solution is to use, optimized presaturation slabs with quadratic phase pulses generated by the Shinnar‐LeRoux algorithm. These can be set to reduce the field of view in the phase‐encoding direction, resulting in a reduction in the number of phase‐encoding steps. For instance, for a 1 × 2‐mm spatial resolution, over a rectangular, 250 × 125‐mm field of view, and using a half Fourier acquisition, an echo‐train length of only 40 is required. With a 4.5‐msec echo spacing, the total imaging time is ≈︁ 180 msec. The efficacy of this solution on phantoms and volunteers is demonstrated. Multislice short‐axis examinations of the whole heart, realized within a single short breath‐hold of ∼ 10 seconds, are shown. The possibility of investigating not only cardiac anatomy but also both contractility and myocardial perfusion is discussed.
Three‐dimensional high‐resolution dynamic contrast‐enhanced MR angiography of the pelvis and lower extremities with use of a phased array coil and subtraction: Diagnostic accuracy
Authors: Yamashita Yasuyuki , Mitsuzaki Katsuhiko , Ogata Ichiro , Takahashi Mutsumasa , Hiai Yasuhiro
Published: March 2007

In this study, our purpose was to compare the high‐resolution contrast‐material‐enhanced three‐dimensional subtraction MR angiography with conventional angiography for occlusive disease in the pelvic and lower extremity arteries. A three‐dimensional fast‐imaging with steady precession (FISP) sequence with a 256 × 512 matrix was obtained on 1.5T MR unit using a phased array coil. Twenty patients with arteriosclerotic obstructive disease underwent subtraction dynamic contrast‐enhanced MR angiography. In 15 patients, three regions (pelvis, upper knee, and lower knee) were sequentially obtained after repeated injection of gadolinium‐diethylenetriamine pentaacetic acid (Gd‐DTPA). In the other five patients, one region was imaged (total of 50 examinations); a maximum‐intensity projection (MIP) algorithm was used for subtracted images. All patients also underwent conventional angiography. Angiographic images were divided into several anatomical segments. Three blinded radiologists independently graded a total of 50 anatomic segments with stenotic or obstructive diseases and 90 segments without disease. Subtracted images allowed resolution of small branch vessels in all examinations, although misregistration was seen in eight examinations of five patients. All arteries larger than 1 mm in diameter were visualized on subtracted images. For detection of significant stenosis (>50%), MR angiography had 96% sensitivity and 83% specificity. The correlation coefficient of degree of agreement between MR angiography and conventional angiography was .92. Stenotic vessels tended to be overestimated. We conclude that high‐resolution dynamic contrast‐enhanced three‐dimensional MR angiography is capable of depicting small vessel anatomy of the pelvis and lower extremities. Sequential MR angiography of different regions was feasible by repeated injection of Gd‐DTPA and subtraction. This technique is highly sensitive in detecting lesions, but stenosis tended to be overestimated.
A new method for imaging perfusion and contrast extraction fraction: Input functions derived from reference tissues
Authors: Kovar David A. , Lewis Marta , Karczmar Gregory S.
Published: March 2007

This study describes a new method for analysis of dynamic MR contrast data that greatly increases the time available for data acquisition. The capillary input function, CB(t), is estimated from the rate of contrast agent uptake in a reference tissue such as muscle, based on literature values for perfusion rate, extraction fraction, and extracellular volume. The rate constant for contrast uptake (the product of perfusion rate, F, and extraction fraction, E; F‐E) is then determined in each image pixel using CB(t), extracellular volume (relative to the reference tissue) measured from MR and the tissue concentration of contrast media as a function of time calculated from the MR data. The “reference tissue method” was tested using rats with mammary (n = 10) or prostate (n = 15) tumors implanted in the hindlimb. Dynamic MR images at 4.7 T were acquired before and after Gd‐DTPA intravenous bolus injections to determine F·EGd‐DTPA. Acquisition parameters were optimized for detection of the first pass of the contrast agent bolus, so that “first‐pass analysis” could be used as the “gold standard” for determination of F·E. The accuracy of values of F·E determined using the reference tissue method was determined based on comparison with first‐pass analysis. In some cases, deuterated water (D2O) was injected IV immediately after Gd‐DTPA measurements, and the reference tissue method was used to calculate F, based on the rate of uptake of D2O. Comparison of rate constants for Gd‐DTPA uptake and D2O uptake allowed calculation of EGd‐DTPA. Values for F·EGd‐DTPA, F, and EGd.DTPA were determined for selected regions and on a pixel‐by‐pixel basis. Values for F·E and EGd.DTPA measured using the reference tissue method correlated well (P = .90 with a standard error of ±.016, n = 15) with values determined based on first‐pass contrast media uptake. The reference tissue method has important advantages: (a) A large volume of reference tissue can be used to determine the contrast agent input function with high precision. (b) Data obtained for 20 minutes after injection are used to calculate F or F·E. The greatly increased acquisition time can be used to increase the spatial resolution, field of view or SNR of measurements. The reference tissue method is most useful when the volume of tissue that must be imaged and/or the spatial resolution required precludes use of traditional first‐pass methods.
Limits to the accuracy of vessel diameter measurement in MR angiography
Authors: Hoogeveen Romhild M. , Bakker Chris J. G. , Viergever Max A.
Published: March 2007

This work addresses the fundamental limits imposed by the MRI process on the accuracy with which vessel diameters and cross‐sectional areas can be derived from time‐of‐flight (TOF) and phase‐contrast (PC) MR source images. By means of simulations and in vitro experiments, it is demonstrated that, even in the absence of flow‐related artifacts, severe inaccuracies in the determination of diameters or cross‐sectional areas may occur solely because of the physical process of the MR image acquisition. Resolution and intraluminal saturation have strong effects on the vessel appearance and thus on the diameter estimation error. It is shown that low resolution leads to diameter overestimation or even underestimation and that intraluminal saturation causes severe underestimation, even for relatively low flip angles. Velocity and velocity encoding do not have a major influence on lumen appearance in PC images. Accurate diameter estimations can be attained only if lumen diameters constitute at least three pixels for both TOF and PC acquisitions, provided that intraluminal saturation is suppressed or avoided. Additionally, since the constitution of TOF and PC images is dissimilar, lumina should be analyzed differently to obtain accurate diameters and cross‐sectional areas.
In Vivo quantitative mapping of cardiac perfusion in rats using a noninvasive MR spin‐labeling method
Authors: Belle Valérie , Kahler Elke , Waller Christiane , Rommel Eberhard , Voll Sabine , Hiller Karl‐Heinz , Bauer Wolfgang R. , Haase Axel
Published: March 2007

Measurement of myocardial perfusion is important for the functional assessment of heart in vivo. Our approach is based on the modification of the longitudinal relaxation time T1 induced by magnetic spin labeling of endogenous water protons. Labeling is performed by selectively inverting the magnetization within the detection slice, and longitudinal relaxation is measured using a fast gradient echo MRI technique. As a result of blood flow, nonexcited spins enter the detection slice, which leads to an acceleration of the relaxation rate. Incorporating this phenomenon in a mathematical model that describes tissue as two compartments yields a simple expression that allows the quantification of perfusion from a slice‐selective and a global inversion recovery experiment. This model takes into account the difference between T1 in blood and T1 in tissue. Our purpose was to evaluate the feasibility and reproducibility of this technique to map quantitatively myocardial perfusion in vivo in rats. Quantitative maps of myocardial blood flow were obtained from nine rats, and the reproducibility of the technique was evaluated by repeating the whole perfusion experiment four times. Evaluation of regions of interest within the myocardium yielded a mean perfusion value of 3.6 ± .5 ml min−1 g‐1 over all animals, which is in good agreement with previously reported literature values.
MRI of patellar articular cartilage: Evaluation of an optimized gradient‐echo sequence (3D‐DESS)
Authors: Ruehm Stefan , Zanetti Marco , Romero José , Hodler Juerg
Published: March 2007

Our purpose was to evaluate the diagnostic efficacy of a gradient‐echo sequence optimized for cartilage imaging in patellar cartilage abnormalities and to compare it to a standard turbo‐spin‐echo sequence. Fifty‐eight consecutive patients who underwent, within 3 months both MRI and arthroscopy or surgery, were included in the investigation. Two radiologists specializing in musculoskeletal imaging independently assessed axial three‐dimensional double‐echo steady state (3D‐DESS) gradient‐echo images and sagittal proton‐ and T2‐weighted turbo‐spin‐echo images with regard to retropatellar cartilage abnormalities. Possible findings were: 0: normal, 1: cartilage softening, and 2: lesion of the articular surface. Inter‐ and intraobserver variability was assessed. For cartilage softening, the axial 3D‐DESS sequence had a sensitivity of 73%, a specifity of 75%, and an accuracy of 70%. The corresponding results for the sagittal turbo‐spin‐echo sequence were 53%, 65%, and 62%. For surface lesions, the results for the 3D‐DESS sequence were 43%, 92%, and 83% and for the turbo‐spin‐echo sequence were 60%, 92%, and 86%. Intra‐ and interobserver agreement was moderate (k = 0.59 and 0.45 [DESS], 0.6 and 0.46 [turbo ‐spin‐echo]). We conclude that the 3D‐DESS sequence is moderately accurate in detecting patellar cartilage abnormalities. Compared with the sagittal turbo‐spin‐echo sequence, the axial 3D‐DESS sequence is superior in diagnosing cartilage softening but not surface lesions.
A compact respiratory‐triggering device for routine microimaging of laboratory mice
Authors: Minard Kevin R. , Wind Robert A. , Phelps Robyn L.
Published: March 2007

A partial‐body plethysmograph was developed for measuring the respiratory flow of anesthetized mice during routine microimaging experiments performed in the close confines of an 89‐mm‐diameter, vertical‐bore magnet. Respiratory flow patterns were used for synchronizing conventional T2‐weighted spin‐echo imaging with the respiratory cycle, thereby, significantly reducing motion‐induced artifacts and increasing observed liver lesion contrast.
Comparison of intranasal with targeted lymph node immunization using PR8‐Flu ISCOM adjuvanted HIV antigens in macaques
Authors: Koopman G. , Bogers W.M.J.M. , van Gils M. , Koornstra W. , Barnett S. , Morein B. , Lehner T. , Heeney J.L.
Published: March 2007

The rapidly spreading HIV epidemic requires a vaccine that elicits potent mucosal immunity to halt or slow transmission. Induction of these responses will depend on the use of appropriate adjuvants and targeting of the mucosal immune system. Previously, immune stimulating complexes (ISCOM) have shown great potency as adjuvant in the induction of mucosal responses in mice and systemic responses in non‐human primates. In this study, HIV formulated in PR8‐Flu ISCOM adjuvant was applied to immunize rhesus macaques against HIV; targeting the mucosa either via intranasal (IN) application or via targeted lymph node immunization (TLNI). While, strong systemic, HIV specific, cytokine, lymphoproliferative, and antibody responses were induced via the TLNI route, the IN application generated only low responses. Furthermore, all four animals immunized via TLNI developed vaginal IgA antibodies against gp120. In conclusion, in contrast to what has been demonstrated in mice, the IN application of PR8‐Flu ISCOM did not induce strong immune responses in rhesus macaques unlike those immunized by the TLNI route. J. Med. Virol. 79:474–482, 2007. © 2007 Wiley‐Liss, Inc.
Differential binding and activation of caspase‐3 in cultured hippocampal neurons by assembly forms of Aβ1–42
Authors: St. John Paul A.
Published: March 2007

Amyloid‐β (Aβ) peptides, the primary constituents of amyloid plaques in the brain in Alzheimer's disease (AD), may cause AD, but how they do so is not clear. Aβ peptides spontaneously aggregate, or self‐assemble, to generate several distinct macromolecular and morphological forms that can differ significantly in their effects on cells. We have compared different assembly forms of Aβ1–42 (Aβ42) for their ability to trigger apoptosis in cultured hippocampal neurons at a submicromolar concentration and for their binding to such neurons. Fibrillar Aβ42 caused both morphological changes indicative of apoptosis and specific activation of caspase‐3, a characteristic marker of neurodegeneration in AD, in hippocampal neurons, whereas other preparations tested did not do so under the same conditions. More aggregated forms of Aβ42, including both fibrils and a mixture of assembly forms termed Aβ‐derived diffusible ligands (ADDLs), bound to neurons much more extensively and at lower concentrations than preparations that contained smaller forms. Fibrillar Aβ42, in particular, bound to neurons at concentrations as low as 1 nM. Colocalization studies showed that fibrillar Aβ42 bound almost exclusively at nonsynaptic sites. These results show differences between assembly forms of Aβ42 in the ability to trigger apoptotic signaling in CNS neurons, and they directly demonstrate differences between assembly forms in the binding to CNS neurons, a possible first step in the pathogenesis of AD. These results suggest that fibrillar Aβ42 contributes to the pathogenesis of AD. © 2007 Wiley‐Liss, Inc.
Barriers to pain management in the rehabilitation of the surgical oncology patient
Authors: Silver Julie , Mayer R. Samuel
Published: March 2007

Virtually every surgical oncology patient faces pain, and it can become a major barrier to rehabilitation and quality of life. Pain must be assessed as to its severity, etiology (somatic, visceral, or neuropathic), causation (directly from malignancy or from treatment side effects), and its impact on daily function. Treatments can include physical modalities, exercise, opioids, adjuvant medications, and interventional techniques. Barriers to treatment may include side effects, finances, and attitudes. New technologies in medication delivery systems, intrathecal pumps, injections, and surgery have greatly strengthened the armamentarium available to manage pain. J. Surg. Oncol. 95:427–435. © 2007 Wiley‐Liss, Inc.
Metastasis‐related factors expressed in pT1 pN0 breast cancer: Assessment of recurrence risk
Authors: Ogura Shigeto , Ohdaira Takeshi , Hozumi Yasuo , Omoto Yawara , Nagai Hideo
Published: March 2007

Objectives

Previous reports have indicated that small breast cancers without lymph node metastasis present a favorable prognosis. However, 10–20% of patients with T1 N0 invasive ductal carcinoma experience recurrence and have a poor prognosis. The objective of this study was to examine whether certain metastasis‐related factors are prognostic of cancer recurrence in such patients at risk for relapse.

Methods

Nineteen patients with the carcinoma who had recurrence 1–15 years after margin‐free resection were examined. The control group consisted of 20 patients with pT1 pN0 invasive ductal carcinoma who had no recurrence for ≥10 years after radical surgery. The two groups were compared with respect to clinical profiles, conventional neoplastic features, and immunohistochemical expressions of 16 metastasis‐related factors.

Results

No significant difference was found between the two groups in clinical profiles and conventional neoplastic features. However, six factors (MMP‐2, MT1‐MMP, T1MP‐2, VEGF, cMET, and PCNA) were significantly expressed in the recurrence group against the control group. MMP‐9 was significantly less expressed in the recurrence group. Of these factors, MMP‐2, MT1‐MMP, and VEGF showed the highest adjusted odds ratios.

Conclusion

MMP family and growth factors may be promising predictors of recurrence risk of early stage breast cancer. J. Surg. Oncol. 2007;96:46–53. © 2007 Wiley‐Liss, Inc.
Highly Efficient and Well‐Controlled Ambient Temperature RAFT Polymerization under Solar Radiation
Authors: Jiang Wending , Lu Lican , Cai Yuanli
Published: March 2007

Highly efficient and well‐controlled ambient temperature reversible addition–fragmentation chain transfer (RAFT) polymerization is readily carried out under environmentally friendly mild solar radiation. This discovery has significantly extended studies from man‐made separated‐spectroscopic‐emission UV‐vis radiation (Macromolecules 2006, 39, 3770) to natural continuous‐spectroscopic‐emission solar radiation for ambient temperature RAFT polymerization.

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Synthesis and Properties of Novel Cross‐Linked Fluoroalkyl End‐Capped Oligomeric Nanoparticles Containing Adamantane Units
Authors: Mugisawa Masaki , Ueno Katsuya , Hamazaki Kazuo , Sawada Hideo
Published: March 2007

Fluoroalkyl end‐capped cooligomers that contain both oxime‐blocked isocyanato and hydroxyadamantyl segments are prepared by the cooligomerization of fluoroalkanoyl peroxide with the corresponding monomers under mild conditions. This fluorinated cooligomer affords new cross‐linked fluoroalkyl end‐capped cooligomeric nanoparticles that contain adamantane segments by the deprotecting reaction of oxime‐blocked isocyanato segments in cooligomers in excellent to moderate isolated yield. A variety of cross‐linked fluoroalkyl end‐capped cooligomeric nanoparticles that contain adamantane segments are also prepared by similar deprotecting reactions with this fluorinated cooligomer in the presence of adamantane‐1,5‐diol. Furthermore, we have prepared cross‐linked fluoroalkyl end‐capped cooligomers that contain oxime‐blocked isocyanato segments by the use of 2‐hydroxyethyl acrylate and poly(ethylene glycol)‐containing methacrylate monomer as comonomers, respectively. However, the deprotecting reactions of the oxime‐blocked isocyanato segments in the cooligomers do not afford the expected nanoparticles, and these cross‐linked cooligomers are found to show a gelling characteristic. The thermal stability of these cross‐linked fluorinated cooligomeric nanoparticles that contain adamantane segments increases significantly compared to that of the parent fluorinated cooligomer. More interestingly, the thermal stability of these cross‐linked fluorinated nanoparticles is almost the same as that of the fluoroalkyl end‐capped acrylic acid oligomer/SiO2 nanocomposites (content of SiO2 in composites: 70%). In addition, these cross‐linked fluorinated nanoparticles have been applied to the surface modification of traditional organic polymers such as poly(methyl methacrylate) to exhibit a good oleophobicity imparted by fluorine on their surface.

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A New Strategy for the Synthesis of Polyaniline Nanostructures: From Nanofibers to Nanowires
Authors: Li Jing , Tang Heqing , Zhang Aiqing , Shen Xiantao , Zhu Lihua
Published: March 2007

A new approach for the synthesis of polyaniline (PANI) nanostructures under UV light illumination has been developed, which is the first report of a templateless chemical process for preparing pure PANI nanowires. The acceleration effect of photo‐assistance on the polymerization can promote the homogeneous nucleation and elongation of the nanofibers and nanowires, leading to easy preparation of tunable diameters of the nanowires and nanofibers of PANI.

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Paroxysmal nonkinesigenic dystonia and celiac disease
Authors: Hall Deborah A. , Parsons Julie , Benke Tim
Published: March 2007

Celiac disease has been associated with ataxia and other neurological signs but has not been associated with paroxysmal nonkinesigenic dyskinesias (PNKD) to date. We present a child with biopsy‐proven celiac disease and a movement disorder resembling PNKD since the age of 6 months. She had complete resolution of her neurological symptoms with introduction of a gluten‐free diet. Because a susceptibility locus for celiac disease has been reported on 2q33 and studies in PNKD show linkage to 2q, this report suggests further genetic investigations around this locus may be useful. We also review the literature regarding the genetic susceptibility to PNKD and celiac disease. © 2007 Movement Disorder Society
Effects of caffeine on the freezing of gait in Parkinson's disease
Authors: Kitagawa Mayumi , Houzen Hideki , Tashiro Kunio
Published: March 2007

Caffeine is a nonselective competitive blockade of adenosine A1 and A2A receptors. In this report, we studied the efficacy of 100 mg of caffeine per day on the freezing of gait (FOG) for patients with Parkinson's disease. Different subtypes of FOG showed different therapeutic responses to caffeine. Caffeine improved “total akinesia” type of FOG, but had no effect on “trembling in place.” Tolerance developed to the beneficial effect of caffeine on FOG within a few months, but a 2‐week caffeine withdrawal period could restore the effect of caffeine. © 2007 Movement Disorder Society
Antiparkinsonian activity of L‐propyl‐L‐leucyl‐glycinamide or melanocyte‐inhibiting factor in MPTP‐treated common marmosets
Authors: Katzenschlager Regina , Jackson Michael J. , Rose Sarah , Stockwell Kim , Tayarani‐Binazir Kayhan A. , Zubair Mohammed , Smith Lance A. , Jenner Peter , Lees Andrew J.
Published: March 2007

The neuropeptide melanocyte‐inhibiting factor (MIF) or L‐propyl‐L‐leucyl‐glycinamide (PLG) has been reported in some studies to improve the motor signs of Parkinson's disease (PD) and in rodent models of PD. In this study of oral and intravenous MIF in N‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP)‐lesioned marmosets, a wide range of doses of MIF administered alone (0.25, 1, 2, 5, 10, 20 mg/kg orally) did not increase locomotor activity, relieve motor disability, or induce dyskinesias. When MIF (1.0 and 5.0 mg/kg orally or 10 and 20 mg/kg intravenously) was administered concomitantly with levodopa/benserazide, no significant differences in motor function or dyskinesias were observed compared with levodopa/benserazide alone. The results of this first study of MIF in the marmoset MPTP model provide no encouragement for the reinvestigation of MIF in the clinical management of the motor signs of PD. © 2007 Movement Disorder Society
Malignant melanoma in early Parkinson's disease: The DATATOP trial
Authors: Constantinescu Radu , Romer Megan , Kieburtz Karl ,   DATATOP Investigators of the Parkinson Study Group
Published: March 2007

The available epidemiological data on the incidence of malignant melanoma in Parkinson's disease are contradictory. The role of levodopa therapy in this context has been debated. We identified all known cases of malignant melanoma (N = 5) in the DATATOP clinical trial cohort and compared that to published expected values (N = 1.5) for a standard healthy population. The standardized event ratio was 3.3 (95% confidence interval, 1.1–7.8), indicating that incidence of malignant melanoma was higher than expected. We found no association between levodopa therapy and the incidence of melanoma. © 2007 Movement Disorder Society
Predictors of freezing in Parkinson's disease: A survey of 6,620 patients
Authors: Macht Michael , Kaussner Yvonne , Möller Jens Carsten , Stiasny‐Kolster Karin , Eggert Karla Maria , Krüger Hans‐Peter , Ellgring Heiner
Published: March 2007

Data from a survey of 6,620 Parkinson's disease patients were examined for correlation of freezing with age, sex, duration, subjective severity of Parkinson's disease, and antiparkinsonian medication. Forty‐seven percent of the patients reported experiencing freezing regularly. Logistic regression analysis showed that freezing was significantly associated with a longer disease duration and a more advanced stage of the disease. Freezing episodes were more likely in men than in women and in patients taking, in addition to levodopa, Entacapone, Amantadine, or dopamine agonists. Finally, patients considering tremor as their main symptom reported freezing less frequently. Common antiparkinsonian drugs given in combination with levodopa were not negatively correlated with freezing. The results underline the necessity to develop appropriate countermeasures against this phenomenon, which is widely known to cause significant impairment of patients' quality of life and—as our data also showed—may cause traffic accidents in licensed patients. © 2007 Movement Disorder Society
Joint additive Kullback–Leibler residual minimization and regularization for linear inverse problems
Authors: Resmerita Elena , Anderssen Robert S.
Published: March 2007

For the approximate solution of ill‐posed inverse problems, the formulation of a regularization functional involves two separate decisions: the choice of the residual minimizer and the choice of the regularizor. In this paper, the Kullback–Leibler functional is used for both. The resulting regularization method can solve problems for which the operator and the observational data are positive along with the solution, as occur in many inverse problem applications. Here, existence, uniqueness, convergence and stability for the regularization approximations are established under quite natural regularity conditions. Convergence rates are obtained by using ana prioristrategy. Copyright © 2007 John Wiley & Sons, Ltd.
Ganglioside mimicry and peripheral nerve disease
Authors: Yuki Nobuhiro
Published: March 2007

Four criteria must be satisfied to conclude that a given microorganism causes Guillain–Barré (GBS) or Fisher (FS) syndrome associated with anti‐ganglioside antibodies: (1) an epidemiological association between the infecting microbe and GBS or FS; (2) isolation in the acute progressive phase of illness of that microorganism from GBS or FS patients with associated anti‐ganglioside IgG antibodies; (3) identification of a microbial ganglioside mimic; and (4) a GBS or FS with associated anti‐ganglioside antibodies model produced by sensitization with the microbe itself or its component, as well as with ganglioside. Campylobacter jejuni is a definitive causative microorganism of acute motor axonal neuropathy and may cause FS and related conditions. Haemophilus influenzae and Mycoplasma pneumoniae are possible causative microorganisms of acute motor axonal neuropathy or FS. Acute and chronic inflammatory demyelinating polyneuropathies may be produced by mechanisms other than ganglioside mimicry. Muscle Nerve, 2007
Atom transfer radical polymerization of styrene initiated by bromoacetylated syndiotactic polystyrene macroinitiator
Authors: Gao Yong , Li Huaming , Wang Xiayu
Published: March 2007

Atom transfer radical polymerization of styrene was conducted with bromoacetylated syndiotactic polystyrene as macroinitiator and copper bromide combined with N,N,N′,N′,N′‐pentamethyldiethylenetriamine as catalyst. A two‐stage process has been developed to synthesize the macroinitiator. First, syndiotactic polystyrene (sPS) was functionalized in the side phenyl rings with acetyl groups using the Friedel–Crafts reaction; second, the acetyl groups were converted to bromoacetyl groups by an acid‐catalyzed halogenation reaction. The initiator was found to be active in the polymerization of styrene, leading to the production of graft chains with well‐defined structure. The molecular weight and molecular weight distribution of the graft chains were determined using gel permeation chromatography after cleaving from the sPS backbone using peroxide acid oxidation followed by hydrazine‐catalyzed hydrolysis. The results indicated that the polymerization process was characteristic of a ‘living’ nature. Copyright © 2007 Society of Chemical Industry
Isolation of dinuclear dihydroxydiphenylmethanes and trinuclear novolacs (triphenylols) from phenol‐formaldehyde condensations
Authors: Moss W. H. , Moss Elsie
Published: March 2007

Previous work has shown that the intermediates in the formation of resins from phenol and formaldehyde— the 2,2′‐, 2,4′‐ and 4,4′‐dihydroxydiphenylmethanes can only be isolated from the reaction products in small yields and with difficulty.

It is now shown that after distillation of excess phenol and formaldehyde from the initial reaction mass at atmospheric pressure, a further high‐temperature steam distillation yields approximately 60% of the remaining product as white crystalline dihydroxydiphenylmethanes, 20% as triphenylols varying from hard crystalline masses to slowly crystallising oils, and 20% of fusible and soluble novolac resin of high melting point.

Some lens‐shaped crystals were also obtained.
Crystallisation kinetics and morphology of high density polyethylene containing organic and inorganic pigments
Authors: Turturro Antonio , Olivero Luigi , Pedemonte Enrico , Alfonso Gian Carlo
Published: March 2007

Some organic pigments, present in very small amounts (0.1 to 0.2%), can cause warpage and shrinkage phenomena in moulded parts of linear polyethylene. Investigations on such phenomena have been carried out by dilatometric and morphological analysis. The influence on polyethylene crystallisation kinetics and morphology of such organic and inorganic pigments, which do not cause any deformation effect, has been studied.

The experimental results show that only organic pigments increase the crystallisation rate, by acting as nucleating agents; in these cases, moreover, the crystalline grain is smaller and the typical morphology of polyethylene crystallised in bulk is altered.

A possible correlation between the nucleating action and the warpage effect of organic pigments on moulded polyethylene is discussed.
The emulsion polymerisation of vinyl acetate by redox initiation
Authors: Elgood Brian G. , Gulbekian Edward V.
Published: March 2007

Redox initiation enables polymerisation to be carried out at relatively low temperatures, and has been extensively studied in relation to styrene‐butadiene and acrylic esters. In the case of vinyl acetate, the hydrogen peroxide‐iron initiator system has been examined in detail, but is normally satisfactory only at higher temperatures of polymerisation (70 to 80 °C).

The low temperature redox polymerisation of vinyl acetate appears to have received little attention. In the present work, the emulsion polymerisation of vinyl acetate using ammonium persulphate with a reducing agent and a metal ion has been studied at 50 ° C. It is shown that to achieve maximum conversion of monomer to polymer the selection of both the reducing agent and the metal ion is important, and that the pH profile during the process is critical. These results are related to the availability of the metal ion at the locus of polymerisation.
Perspectives on research evidence and clinical practice: a survey of Australian physiotherapists
Authors: Grimmer‐Somers Karen , Lekkas Peter , Nyland Leah , Young Alexandra , Kumar Saravana
Published: March 2007

Background and Purpose. Physiotherapists' use of research evidence with clinical decision‐making has interested researchers world‐wide since 1980; however, little is known about such practices in Australia. The present survey sought information on Australian physiotherapists' perceptions of the importance of research, and barriers to uptake of evidence in clinical practice, when compared with an international cohort from 2001. Method. An Australian‐relevant version of an English (UK) National Health Service (NHS) survey instrument was used to canvass 453 physiotherapists, randomly selected from the South Australian Physiotherapy Registration Board 2004–2005 records. The first survey was mailed in August 2005, a reminder was sent two weeks later to non‐responders and a follow‐up survey was sent in April 2006 to non‐responders whose addresses had changed since 2005. Results. There was a 51% response rate. Of the non‐responders, 12% were not contactable at their listed address, highlighting the mobility of Australian physiotherapists. Most respondents had undertaken research as students (59.5%) or as students and clinicians (11.5%). Of these, 37.1% were encouraged to embark on more research, and 20.5% were discouraged. The significant predictors of positive perceived importance of research were: previous research experience; being positive about undertaking further research; working in hospitals and holding a postgraduate degree. Clinicians working privately were significantly less likely than managers to be positive about research importance. The only significant predictor for not perceiving barriers to uptake of evidence was being positive about undertaking future research. Conclusions. The study identified constraints on uptake of evidence into practice that were related to accessing, reading and interpreting published research, and implementing findings. Found consistently across employment categories were barriers relating to lack of time, uncertainty about what the research reported, scepticism about the value of research and being isolated from peer support and literature sources. The responses indicated a positive shift towards evidence uptake since the 2001 NHS survey, suggesting an influence of increased exposure to information on evidence‐based practice. A greater focus on research whilst training, the application of educational strategies for empowerment, better knowledge transfer and upskilling within the workplace, and ensuring dedicated time and organizational support for research activities are indicated. Copyright © 2007 John Wiley & Sons, Ltd.
Mutational analysis ofSPANXgenes in families with X‐Linked prostate cancer
Authors: Kouprina Natalay , Noskov Vladimir N. , Solomon Greg , Otstot John , Isaacs William , Xu Jianfeng , Schleutker Johanna , Larionov Vladimir
Published: March 2007

BACKGROUND

Previous genetic linkage studies identified a locus for susceptibility to prostate cancer calledHPCXat Xq27. The candidate region contains two clusters ofSPANXgenes. The first cluster calledSPANX‐A/DincludesSPANX‐A1,SPANX‐A2,SPANX‐B,SPANX‐C, andSPANX‐D; the second cluster calledSPANX‐NincludesSPANX‐N1,SPANX‐N2,SPANX‐N3, andSPANX‐N4. TheSPANXgenes encode cancer‐testis (CT) specific antigens. Previous studies identifiedSPANX‐BandSPANX‐Dvariants produced by gene conversion events, none of which are associated with X‐linked prostate cancer.

METHODS

In this study we applied transformation‐associated recombination cloning (TAR) in yeast to analyze sequence variations inSPANX‐A1,SPANX‐A2, andSPANX‐Cgenes that are resided within large chromosomal duplications. ASPANX‐N1/N4cluster was analyzed by a routine PCR analysis.

RESULTS

None of the sequence variations in the coding regions of these genes is associated with susceptibility to prostate cancer.

CONCLUSIONS

Therefore, genetic variation in theSPANXgenes is not the actual target variants explaining HPCX. However, it is possible that they play a modifying role in susceptibility to prostate cancer through complex recombinational interaction. Prostate 67: 820–828, 2007. © 2007 Wiley‐Liss, Inc.
Recognition of Cdk2 by Cdk7
Authors: Lolli Graziano , Johnson Louise N.
Published: March 2007

Cdk7, a member of the cyclin dependent protein kinase family, regulates the activities of other Cdks through phosphorylation on their activation segment, and hence contributes to control of the eukaryotic cell cycle. Cdk7 is itself phosphorylated on the activation segment. Cdk7 phosphorylates Cdk1, Cdk2, Cdk4, and Cdk6, but only Cdk1 and Cdk2 can phosphorylate Cdk7 and none of them is able to auto‐phosphorylate. The activation segments of the Cdks are very similar in sequence. Their specificity does not appear to be dictated by the sequences surrounding the phosphorylation sites but by structural determinants at remote sites. Through mutagenesis studies, we have identified regions in Cdk2 responsible for its interaction with Cdk7. A model has been built that explains the molecular basis for the specificity observed in Cdk recognition. The two kinases are arranged in a quasi‐symmetric head‐to‐tail arrangement in which the N‐terminal lobe from one kinase docks against the C‐terminal lobe from the other kinase, and the activation segments are within reach of the opposite catalytic sites. Further experiments demonstrate that cyclin A hydrophobic pocket is not a recruitment site for Cdk7. Proteins 2007. © 2007 Wiley‐Liss, Inc.
ZnO:Mn:Cu nanowires prepared by template method
Authors: Sima Marian , Enculescu Ionut , Sima Mariana , Enache Mihaela , Vasile Eugen , Ansermet Jean‐Philippe
Published: March 2007

Manganese and copper doped ZnO films and nanowire arrays were prepared by cathodic electrodeposition from aqueous solution. The electrochemical process was examined by linear voltammetry and the morphology and the composition of obtained semiconductor were observed by SEM and EDX measurements. Optical absorption spectra indicated the presence of copper in ZnO:Mn:Cu nanowire arrays as Cu2+ ions. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Infrared properties of cirrus clouds in climate models
Authors: De Leon Ruben Rodriguez , Haigh Joanna D.
Published: March 2007

The representation in global climate models of the infrared radiative properties of cirrus clouds is assessed by comparing their radiative forcing calculated using airborne in‐situ‐measured size distributions and retrievals from combined lidar and Doppler‐radar data. The latter are fitted to a bimodal function, allowing the inclusion of the size distribution's shape, normally omitted in the characterization of cirrus.

The impact of the particle size distribution's shape on the atmosphere's radiation fields is evaluated using a two‐stream radiative code. The comparisons show that the effect of the shape of the size distributions used to calculate the radiative forcing of a cirrus layer composed of hexagonal cylinders is not negligible, evidencing the ambiguity linked to the commonly used two‐parameter (effective radius and ice water content) characterization of cirrus, and showing that the inclusion of a simple measure of the relative concentration of small particles improves its radiative parameterization. Copyright © 2007 Royal Meteorological Society
An innovation method for estimating radar radial‐velocity observation error and background wind error covariances
Authors: Xu Qin , Nai Kang , Wei Li
Published: March 2007

By using the non‐isotropic form of error covariance function derived for radial‐velocity fields on conical surfaces of low‐elevation radar scans, the conventional innovation method is reformulated to estimate Doppler radar radial‐velocity observation error covariance and background vector wind error covariance from time series of radar radial‐velocity innovation (observation minus independent background) fields. The method is applied to radar radial‐velocity innovation data obtained at the lowest elevation of radar scans for a real case. The results show that radar radial‐velocity observation errors are correlated between neighbouring range gates and between neighbouring beams. The radial‐velocity observation error correlation functions are estimated, along with the observation error variance and background vector wind error covariance functions, by the reformulated method. Published in 2007 by John Wiley & Sons, Ltd.