bluuebunny/crossref_metadata_2025 huggingface dataset:
Two novel point mutations in the long‐range SHH enhancer in three families with triphalangeal thumb and preaxial polydactyly
Authors: Gurnett Christina A. , Bowcock Anne M. , Dietz Frederick R. , Morcuende Jose A. , Murray Jeffrey C. , Dobbs Matthew B.
Published: December 2006

Spatio‐temporal expression of sonic hedgehog (SHH) is driven by a regulatory element (ZRS) that lies 1 Mb upstream from SHH. Point mutations within the highly conserved ZRS have been described in the hemimelic extra toes mouse and in four families with preaxial polydactyly [Lettice et al., 2003]. Four North American Caucasian families were identified with autosomal dominant triphalangeal thumb. DNA from 20 affected and 36 unaffected family members was evaluated by sequence analysis of a 774‐bp highly conserved ZRS contained within LMBR1 intron 5. Mutations within ZRS were identified in three of four families. In pedigree A and C, a novel A/G transition was identified near the 5′ end of ZRS at bp 739 that segregated with disease or carrier status. Pedigree A, described previously [Dobbs et al., 2000], is a large family with 19 affected members who exhibit a milder phenotype, including predominantly triphalangeal thumbs and low penetrance (82%) relative to other families. Pedigree C is a small family with two affected family members with triphalangeal thumb, and one affected with both triphalangeal thumb and preaxial polydactyly. A novel C/G mutation at bp 621 was identified in pedigree B that segregated with the disease in all four affected individuals who manifested both preaxial polydactyly and triphalangeal thumb. Both mutations alter putative Cdx transcription factor binding sites. Mutations within ZRS appear to be a common cause of familial triphalangeal thumb and preaxial polydactyly. A genotype/phenotype correlate is suggested by pedigree A, whose mutation lies near the 5′ end of ZRS; this family demonstrates a higher rate of nonpenetrance and milder phenotype. However, modifier genes may be contributing to the milder phenotype in this family. © 2006 Wiley‐Liss, Inc.
Anophthalmia‐plus syndrome: A clinical report and review of the literature
Authors: Makhoul Imad R. , Soudack Michalle , Kochavi Orna , Guilburd Joseph N. , Maimon Shimon , Gershoni‐Baruch Ruth
Published: December 2006

We describe a term male infant of healthy non‐consanguineous parents, born with congenital malformations, including bilateral cleft palate and lip, mild microphthalmia with iris coloboma and glaucoma of the right eye, and blepharophimosis with severe microphthalmia of the left eye. Spine radiograph and MRI showed first sacral hemivertebra with spina bifida, and agenesis of the 2nd, 3rd, 4th, and 5th sacral vertebrae and coccyx. Spine MRI showed caudal tethering of spinal cord at L3 level, filum terminalis lipoma and a syringomyelia. Brain ultrasound and MRI showed hypoplasia of corpus callosum with mild dilatation of the lateral ventricles. Orbital MRI showed bilateral microphthalmia—distorted small left eyeball with posteriorly located lens, and a split vitreous body in the right eye, suggestive of primary hyperplastic vitreous. The karyotype was normal. Summary of the findings in nine cases (our case and eight published cases) support the notion that anophthalmia‐plus syndrome (APS) is a distinct syndrome. Gene locus of APS is yet to be identified. © 2006 Wiley‐Liss, Inc.
Synthesis and Antiviral Evaluation of Some Sugar Arylglycinoylhydrazones and Their Oxadiazoline Derivatives
Authors: Abdel‐Aal Mohammed T. , El‐Sayed Wael A. , El‐Ashry El‐Sayed H.
Published: December 2006

Sugar N‐arylaminoacetylhydrazones 2–5 were prepared by the reaction of N‐arylaminoacetylhydrazides 1 with equivalent amounts of the corresponding monosaccharides. Per‐O‐acetyl derivatives 6‐9 of sugar hydrazones 2–5 were prepared by using acetic anhydride in pyridine at room temperature, while on boiling with acetic anhydride, cyclization had taken place to give the oxadiazolines 10–12. The prepared compounds were tested for antiviral activity against Herpes Simplex virus type‐1 (HSV‐1) and hepatitis‐A virus (HAV, MBB‐cell culture adapted strain). Plaque reduction infectivity assay was used to determine virus count reduction as a result of treatment with tested compounds.
Molecular portrait of high productivity in recombinant NS0 cells
Authors: Seth Gargi , Philp Robin J. , Lau Ally , Jiun Kok Yee , Yap Miranda , Hu Wei‐Shou
Published: December 2006

Many important therapeutic proteins are produced in recombinant mammalian cells. Upon the introduction of the product gene, the isolated clones typically exhibit a wide range of productivity and high producers are subsequently selected for use in production. Using DNA microarray, two‐dimensional gel electrophoresis (2DE), and iTRAQ™ as global surveying tools, we examined the transcriptome and proteome profiles of 11 lines of NS0 cells producing the same antibody molecule. Genes that are significantly differentially expressed between high and low producer groups statistically fall into a number of functional classes. Their distribution among the functional classes differs somewhat between transcriptomic and proteomic results. Overall, a high degree of consistency between transcriptome and proteome analysis are seen, although some genes exhibiting inconsistent trends between transcript and protein levels were observed as expected. In a novel approach, functional gene networks were retrieved using computational pathway analysis tools and their association with productivity was tested by physiological comprehension of the possible pathways involved in high recombinant protein production. Network analysis indicates that protein synthesis pathways were altered in high producers at both transcriptome and proteome levels, whereas the effect on cell growth/death pathways was more prominent only at the transcript level. The results suggest a common mechanism entailing the alteration of protein synthesis and cell growth control networks leading to high productivity. However, alternate routes with different sets of genes may be invoked to give rise to the same mechanistic outcomes. Such systematic approaches, combining transcriptomic and proteomic tools to examine high and low producers of recombinant mammalian cells will greatly enhance our capability to rationally design high producer cells. This work is a first step towards shedding a new light on the global physiological landscape of hyper productivity of recombinant cells. Biotechnol. Bioeng. 2007;97: 933–951. © 2006 Wiley Periodicals, Inc.
Perfusion flow bioreactor for 3D in situ imaging: Investigating cell/biomaterials interactions
Authors: Stephens J.S. , Cooper J.A. , Phelan F.R. , Dunkers J.P.
Published: December 2006

The capability to image real time cell/material interactions in a three‐dimensional (3D) culture environment will aid in the advancement of tissue engineering. This paper describes a perfusion flow bioreactor designed to hold tissue engineering scaffolds and allow for in situ imaging using an upright microscope. The bioreactor can hold a scaffold of desirable thickness for implantation (>2 mm). Coupling 3D culture and perfusion flow leads to the creation of a more biomimetic environment. We examined the ability of the bioreactor to maintain cell viability outside of an incubator environment (temperature and pH stability), investigated the flow features of the system (flow induced shear stress), and determined the image quality in order to perform time‐lapsed imaging of two‐dimensional (2D) and 3D cell culture. In situ imaging was performed on 2D and 3D, culture samples and cell viability was measured under perfusion flow (2.5 mL/min, 0.016 Pa). The visualization of cell response to their environment, in real time, will help to further elucidate the influences of biomaterial surface features, scaffold architectures, and the influence of flow induced shear on cell response and growth of new tissue. Biotechnol. Bioeng. 2007;97: 952–961. © 2006 Wiley Periodicals, Inc.
Proteome analysis of heat shock protein expression in Pseudomonas alcaligenes NCIMB 9867 in response to gentisate exposure and elevated growth temperature
Authors: Zhao Bing , Yeo Chew Chieng , Tan Chew Ling , Poh Chit Laa
Published: December 2006

Pseudomonas alcaligenes NCIMB 9867 (strain P25X) degrades xylenols and cresols via the gentisate pathway. P25X expresses two isofunctional gentisate 1,2‐dioxygenases (GDO I and GDO II). The expression of both GDOs was not detected when P25X cells were grown at 42°C, even in the presence of gentisate. A total of 19 heat shock proteins (Hsps) belonging to the Hsp100, Hsp90, Hsp70, Hsp60, Hsp45, and small heat shock protein (sHsp) families were identified among the protein spots that were either newly detected or were expressed at levels of at least twofold higher when P25X cells were cultured at 32 or 42°C in the presence and absence of gentisate. Among these, 16 Hsps were commonly expressed at 42°C. Two additional Hsps (H5 and H13) from the Hsp90 and Hsp60 families, respectively, were expressed only when P25X cells were grown at 42°C and in the presence of gentisate. A protein of the sHsp (H16) family was expressed only in the presence of gentisate at 32°C but not at 42°C. The GroEL chaperonins of the Hsp60 family comprised the largest group of Hsps identified and exhibited high level of expression at 42°C following gentisate exposure. Biotechnol. Bioeng. 2007;97: 506–514. © 2006 Wiley Periodicals, Inc.
Perfusion culture process plus H2O2 stimulation for efficient astaxanthin production by Xanthophyllomyces dendrorhous
Authors: Liu Yuan Shuai , Wu Jian Yong
Published: December 2006

A semicontinuous perfusion culture process (repeated medium renewal with cell retention) was evaluated together with batch and repeated fed‐batch processes for astaxanthin production in shake‐flask cultures of Xanthophyllomyces dendrorhous. The perfusion process with 25% medium renewal every 12 h for 10 days achieved a biomass density of 65.6 g/L, a volumetric astaxanthin yield of 52.5 mg/L, and an astaxanthin productivity of 4.38 mg/L‐d, which were 8.4‐fold, 5.6‐fold, and 2.3‐fold of those in the batch process, 7.8 g/L, 9.4 mg/L, and 1.88 mg/L‐d, respectively. The incorporation of hydrogen peroxide (H2O2) stimulation of astaxanthin biosynthesis into the perfusion process further increased the astaxanthin yield to 58.3 mg/L and the productivity to 4.86 mg/L‐d. The repeated fed‐batch process with 8 g/L glucose and 4 g/L corn steep liquor fed every 12 h achieved 42.2 g/L biomass density, 36.5 mg/L astaxanthin yield, and 3.04 mg/L‐d astaxanthin productivity. The lower biomass and astaxanthin productivity in the repeated fed‐batch than in the perfusion process may be mostly attributed to the accumulation of inhibitory metabolites such as ethanol and acetic acid in the culture. The study shows that perfusion process plus H2O2 stimulation is an effective strategy for enhanced astaxanthin production in X. dendrorhous cultures. Biotechnol. Bioeng. 2007;97: 568–573. © 2006 Wiley Periodicals, Inc.
Consumer confusion in the Thai mobile phone market
Authors: Leek Sheena , Chansawatkit Suchart
Published: December 2006

Consumer confusion is likely to be an ever increasing problem as customers live in an environment where they are bombarded with information and where rapid technological developments are taking place. Although consumer confusion has been investigated in individualistic cultures such as the United Kingdom, it has received little attention in collectivist cultures such as Thailand. This research examines confusion in the Thai mobile phone industry. More specifically, it aims to determine what aspects of the mobile phone industry are confusing and what sources of information are used to reduce or eliminate it. Thai consumers experience confusion and find a number of aspects of the mobile phone industry to be problematic especially handsets, services and tariffs. In terms of reducing confusion, family and friends are the most popular source of information being both credible and reliable. It is put forward that the problems associated with handsets, services and tariffs are due to differing degrees of technological complexity and overchoice both of which are sub‐components of confusion. Copyright © 2006 John Wiley & Sons, Ltd.
Different to ‘dust collectors’? The giving and receiving of experience gifts
Authors: Clarke Jackie R.
Published: December 2006

Gift giving theory has evolved around the giving and receiving of physical goods, yet experiences as gifts are increasingly important in modern Western economies. This research generating data from consumer informants focuses exclusively on experiences. The donor, recipient, occasion and gift, and the three gift giving process stages provide a synthesising framework for the findings. The concepts of donor sacrifice of time and effort, alongside gift surprise emerge as especially pertinent to experience gift giving, and notions of sharing, suspense and recipient sacrifice reinforce the proposition that experience gifts are deserving of researcher effort to better understand the phenomenon. Copyright © 2006 John Wiley & Sons, Ltd.
Carbon Dioxide Activation by Surface Excess Electrons: An EPR Study of the CO2− Radical Ion Adsorbed on the Surface of MgO
Authors: Chiesa Mario , Giamello Elio
Published: December 2006

The CO2− radical anion has been generated at the surface of MgO by direct electron transfer from surface trapped excess electrons and characterized by electron paramagnetic resonance spectroscopy. Both 13C and 17O hyperfine structures have been resolved for the first time, leading to a detailed mapping of the unpaired electron spin density distribution over the entire radical anion. The magnetic equivalence of the two O nuclei has been ascertained allowing a side‐on adsorption structure at low‐coordinate Mg2+ ions to be proposed for the surface stabilized radical.
Crystal and molecular structures of trichloro‐cobalt(II) complexes of epiquinine, epiquinidine, and epidihydrocinchonine
Authors: Tesarowicz Iwona , Oleksyn Barbara J. , Nitek Wojciech
Published: December 2006

Cinchona alkaloids are very well known antimalarials but the mechanism of their biological action still remains to be elucidated. The structural studies of active erythro and inactive threo alkaloid complexes are an important step to this aim. In this paper results of crystal structure analysis of three cobalt complexes of threo alkaloids are presented: (epiquininium)trichlorocobalt(II) (EpiQnCoCl3), (epiquinidinium)trichlorocobalt(II) (EpiQdCoCl3) and (epidihydrocinchoninium)trichlorocobalt(II) (EpiCnCoCl3). The complexes are zwitterions in which trichlorocobalt substituents are coordinated to quinoline nitrogen atoms and quinuclidine nitrogen atoms are protonated. EpiQnCoCl3 adopts uncommon conformation with quinoline moiety oriented in the opposite direction in comparison to the analogous uncomplexed alkaloid. The packing in the crystal structures is determined mainly by the hydrogen bonds, in which the chlorine atoms of substituents and solvent molecules contribute. Atoms participating in hydrogen bonds in EpiQnCoCl3 and EpiQdCoCl3 form large rings, while in EpiCnCoCl3 only chains are present. Solvent molecules are very important for the packing mode. In contrast to most erythro alkaloids, the hydroxyl oxygen atom in the title complexes forms weak or not well defined hydrogen bonds. The contribution of very weak intramolecular interactions N1H1…O12 cannot be excluded. Such “trace” interactions can be considered a relic of the unprotonated status of an epi alkaloid. Chirality, 2007. © 2006 Wiley‐Liss, Inc.
Synthesis and Transition Metal Complexes of Novel N,N,O Scorpionate Ligands Suitable for Solid Phase Immobilisation (Eur. J. Inorg. Chem. 24/2006)
Authors: Hübner Eike , Haas Thomas , Burzlaff Nicolai
Published: December 2006

The cover picture shows the constellation scorpio (lat. scorpius), which symbolises the heteroscorpionate ligands described in the article. To the left, a complex bearing such a heteroscorpionate ligand is fixed on a solid phase. In the back, another ligand with a linker for immobilisation is approaching the resin. The IR spectra (from bottom to top) correspond to a homogenous tricarbonylmanganese complex, the solid phase, a control experiment and a tricarbonyl complex grafted on the solid phase. The A1 and two E bands prove the facial coordination of the ligands and the fixation of the ligand on the solid phase. Details are discussed in the article by N. Burzlaff et al. on p. 4989 ff.
Effects of alternative reinforcer and craving on the choice to smoke cigarettes in the laboratory
Authors: Bisaga Adam , Padilla Margarita , Garawi Fatima , Sullivan Maria A. , Haney Margaret
Published: December 2006

We examined to what extent craving for cigarettes and the magnitude of an alternative monetary reinforcer were predictors of the choice to smoke in the human laboratory. Twelve non‐treatment‐seeking nicotine‐dependent volunteers participated in a series of outpatient sessions during which they had repeated opportunities to select between three puffs of a cigarette and a variety of monetary alternatives ($0.50–3), responding under a progressive‐ratio schedule. Level of cigarette craving was measured at baseline and between each choice opportunity. The probability of choosing a cigarette decreased significantly with the increase in the magnitude of the alternative reinforcer. Baseline level of craving did not significantly alter the probability of choosing a cigarette, but a craving component related to the anticipation of positive effects from smoking, assessed repeatedly between choice opportunities, was predictive of the choice to smoke. These results demonstrate that the cigarette puff self‐administration procedure is sensitive to environmental manipulations and cigarette puff choice can be modified by the availability of an alternative reinforcer. This paradigm models the motivational component associated with choice to smoke and could be used to evaluate the effects of pharmacological and behavioral interventions to decrease cigarette smoking. Copyright © 2006 John Wiley & Sons, Ltd.
Chlorpromazine and apigenin reduce adenovirus replication and decrease replication associated toxicity
Authors: Kanerva Anna , Raki Mari , Ranki Tuuli , Särkioja Merja , Koponen Jarmo , Desmond Renee A. , Helin Aija , Stenman Ulf‐Håkan , Isoniemi Helena , Höckerstedt Krister , Ristimäki Ari , Hemminki Akseli
Published: December 2006

Background

Adenoviruses can cause severe toxicity in immunocompromised individuals. Although clinical trials have confirmed the potency and safety of selectively oncolytic adenoviruses for treatment of advanced cancers, increasingly effective agents could result in more toxicity and therefore it would be useful if replication could be abrogated if necessary.

Methods

We analyzed the effect of chlorpromazine, an inhibitor of clathrin‐dependent endocytosis and apigenin, a cell cycle regulator, on adenovirus replication and toxicity. First, we evaluated the in vitro replication of a tumor targeted Rb‐p16 pathway selective oncolytic adenovirus (Ad5/3‐Δ24) and a wild‐type adenovirus in normal cells, fresh liver samples and in ovarian cancer cell lines. Further, we analyzed the in vitro cell killing efficacy of adenoviruses in the presence and absence of the substances. Moreover, the effect on in vivo efficacy, replication and liver toxicity of the adenoviruses was evaluated.

Results

We demonstrate in vitro and in vivo reduction of adenovirus replication and associated toxicity with chlorpromazine and apigenin. Effective doses were well within what would be predicted safe in humans.

Conclusions

Chlorpromazine and apigenin might reduce the replication of adenovirus, which could provide a safety switch in case replication‐associated side effects are encountered in patients. In addition, these substances could be useful for the treatment of systemic adenoviral infections in immunosuppressed patients. Copyright © 2006 John Wiley & Sons, Ltd.
Labeling G‐rich oligonucleotides (GROs) with N‐succinimidyl 4‐[18F]fluorobenzoate (S18FB)
Authors: Li Junling , Trent John O. , Bates Paula J. , Ng Chin K.
Published: December 2006

Three G‐rich oligonucleotides (GROs) were conjugated with N‐succinimidyl 4‐[18F]fluorobenzoate (S18FB). The yields for GRO5, the shortest sequence among those three GROs being tested, were 42, 70, 84, and 99% at GRO5 concentration of 59, 118, 236, and 472 nmol/100 µl, respectively. Reaction temperature (22 and 40°C), reaction time (15 and 30 min), and borate buffer concentration (25 and 50 mM) showed no noticeable effects on the labeling results. Two longer sequences of GROs, GRO15A and GRO26A, were also labeled with the same procedures and the corresponding yields were 80 ± 2% at 93 nmol/100 µl (n = 3) and 47 ± 3% at 98 nmol/100 µl (n = 3), respectively. Finally, CROa was conjugated with S18FB to further confirm our results. The radiochemical yields were 13.7 ± 2.5, 40.9 ± 3.5, 70.1 ± 2.0, 93.4 ± 1.4% at 8.7, 17.5, 35 and 52.5 OD of CROa (non‐isolated, decay‐corrected and based on S18FB, n = 3) in comparison to 7, 17, 22 and 28% at 5, 10, 20 and 40 OD of CROa, respectively, as reported by Hedberg et al. (Acta Chem Scand 1998; 52: 1034–1039). Copyright © 2006 John Wiley & Sons, Ltd.
Correlation between diffusion in lumbar intervertebral disks and lumbar artery status: Evaluation with fresh blood imaging technique
Authors: Tokuda Osamu , Okada Munemasa , Fujita Takeshi , Matsunaga Naofumi
Published: December 2006

Purpose

To evaluate the correlation of the lumbar artery status with the diffusion values in lumbar vertebral disks in patients with low back problems using a fresh blood imaging (FBI) technique.

Materials and Methods

First, both digital subtraction angiography (DSA) and MR angiography (MRA) was performed, and the weighted kappa value between DSA and MR angiography in evaluating the status of lumbar arteries was calculated. Then, The sagittal diffusion‐weighted MR images in 260 intervertebral disks (L1‐2 to L4‐5) and MR angiographic images using FBI technique in the corresponding 260 lumbar artery pairs (total of 520 arteries) of the 65 patients with low back problems were separately evaluated by two radiologists.

Results

The weighted kappa value between DSA and MRA in evaluating the status of lumbar arteries in both observes indicated good agreement. There were significant correlations between the status of lumbar arteries and the ADC values of the lumbar disks in all orthogonal directions (x, y, and z) at all intervertebral levels except L4‐5 by both observers (P < 0.001).

Conclusion

There is a strong association between the diminished flow in lumbar arteries and the decreased diffusion of lumbar intervertebral disks at all intervertebral levels except at L4‐5. J. Magn. Reson. Imaging 2007. © 2006 Wiley‐Liss, Inc.
Investigation of muscle lipid metabolism by localized one‐ and two‐dimensional MRS techniques using a clinical 3T MRI/MRS scanner
Authors: Velan S. Sendhil , Durst Christopher , Lemieux Susan K. , Raylman Raymond R. , Sridhar Rajagopalan , Spencer Richard G. , Hobbs Gerald R. , Thomas M. Albert
Published: December 2006

Purpose

To demonstrate the feasibility of estimating the relative intra‐ and extramyocellular lipid (IMCL and EMCL) pool magnitudes and calculating the degree of lipid unsaturation within soleus muscle using single‐voxel localized one‐ and two‐dimensional (1D and 2D) MR spectroscopy (MRS).

Materials and Methods

Localized 1D point resolved spectroscopy (PRESS) and 2D correlation spectroscopy (L‐COSY) were performed in identical locations in the soleus muscle of 10 healthy subjects. A GE 3‐T MRI/MRS scanner and a quadrature extremity transmit/receive coil was used.

Results

The 1D and 2D MR spectra were used to compute IMCL/creatine (Cr) and EMCL/Cr ratios. In addition to cross peaks between the methyl and methylene protons in the high‐field region, the 2D spectra showed cross peaks due to J‐coupling between allylic, diallylic methylene pro‐ tons, and olefinic protons. The cross‐peak volume ratios also provided a measure of double bonds, suggesting that this ratio can be used to assess unsaturation within IMCL and EMCL lipid pools.

Conclusion

We have demonstrated the feasibility of detecting 2D cross peaks between different groups of IMCL and EMCL, including the unsaturated protons within these two lipids pools. This protocol may be easily extended to study the lipids present in other tissues. J. Magn. Reson. Imaging 2007. © 2006 Wiley‐Liss, Inc.
Shoulder MR arthrography: In vitro determination of optimal gadolinium dilution as a function of field strength
Authors: Stecco Alessandro , Brambilla Marco , Puppi Anna M.A. , Lovisolo Marta , Boldorini Renzo , Carriero Alessandro
Published: December 2006

Purpose

To find the optimal contrast agent dilution to maximize signal intensity (SI), signal‐to‐noise ratio (SNR), and contrast‐to‐noise ratio (CNR) in shoulder MR arthrography using MR systems operating at different magnetic field strengths.

Materials and Methods

Autoptic human glenohumeral ligaments were inserted in eight egg‐shaped 20‐mL phantoms filled with saline and gadolinium diethylenetriaminepentaacetic acid bismethylamide (Gd‐DTPA‐BMA) in different dilutions of 0.5, 1, 2, 2.5, 5, 12.5, 50 mmol/liter, to simulate the shoulder articular capsule. These phantoms were inserted inside two plastic 240‐mL phantoms filled with water. MRI was performed on 0.2‐, 0.5‐, 1.0‐, 1.5‐, and 3.0‐T MR systems using a three‐dimensional gradient echo (GRE)‐T1‐weighted pulse sequence. SI, SNR, and CNR were determined.

Results

Peak SI and SNR were found at 5 mmol/liter, with the exception of the 0.2‐T scanner, where the maximum was at 2 mmol/liter. Peak CNR was observed at 1 mmol/liter for the 3‐T scanner, at 2 mmol/liter for the 0.2‐ and 0.5‐T scanners, and at 5 mmol/liter for the remaining scanners.

Conclusion

The optimal SI and SNR are provided by 5 mmol/liter contrast agent dilution. Peak CNR was found in a range between 1 and 5 mmol/liter dilutions, depending on the strength of the magnetic field. J. Magn. Reson. Imaging 2007. © 2006 Wiley‐Liss, Inc.
Two‐dimensional population map of cortical connections in the human internal capsule
Authors: Zarei Mojtaba , Johansen‐Berg Heidi , Jenkinson Mark , Ciccarelli Olga , Thompson Alan J. , Matthews Paul M.
Published: December 2006

Purpose

To exploit diffusion imaging tractography to produce a two‐dimensional (xy) probabilistic population map of the cortical connections within the human internal capsule (IC).

Materials and Methods

Diffusion tensor imaging (DTI) was carried out on 11 healthy volunteers. We parceled an axial section of the IC according to its connections to the prefrontal, premotor, primary motor, primary somatosensory, posterior parietal, and occipital cortices using our locally developed probabilistic algorithm.

Results

A consistent topographical organization was generated that was consistent with our anatomical knowledge of the IC. In addition, our study shows that in humans the anterior half of the IC is occupied by the prefrontal cortex.

Conclusion

This map may be of clinical use for correlating neurological deficit with hemispheric lesions, particularly those that affect sensorimotor function. J. Magn. Reson. Imaging 2007. © 2006 Wiley‐Liss, Inc.
Diagnosis of breast tumors by contrast‐enhanced MR imaging: Comparison between the diagnostic performance of dynamic enhancement patterns and morphologic features
Authors: Goto Mariko , Ito Hirotoshi , Akazawa Kentaro , Kubota Takao , Kizu Osamu , Yamada Kei , Nishimura Tsunehiko
Published: December 2006

Purpose

To compare the diagnostic performance of breast lesions by the enhancement patterns and morphologic criteria on magnetic resonance imaging (MRI).

Materials and Methods

Both T1‐weighted 3D gradient‐echo sequences with high temporal resolution and high‐spatial‐resolution MRI were performed on 190 patients with a total of 204 enhancing lesions (144 malignant and 60 benign). The enhancement patterns and morphologic features of each mass and nonmass lesion were analyzed, and the diagnostic performance was compared.

Results

The sensitivity and specificity of the morphologic criteria were statistically significantly higher than those of the enhancement patterns (sensitivity: P = 0.0012, specificity: P = 0.0003), and the Az values for the three observers were 0.900, 0.919, and 0.900. The diagnostic accuracy of the morphologic criteria for both types of lesions was superior, and the differences were statistically significant (mass: P = 0.0001, nonmass: P = 0.0389).

Conclusion

The analysis of the morphologic features of enhancing breast lesions alone showed higher diagnostic performance; therefore, signal intensity (SI) time‐course data may not be needed to diagnose malignant breast lesions. J. Magn. Reson. Imaging 2007. © 2006 Wiley‐Liss, Inc.
High‐precision determination of 18O/16O ratios of silver phosphate by EA‐pyrolysis‐IRMS continuous flow technique
Authors: Lécuyer Christophe , Fourel François , Martineau François , Amiot Romain , Bernard Aurélien , Daux Valérie , Escarguel Gilles , Morrison John
Published: December 2006

A high‐precision, and rapid on‐line method for oxygen isotope analysis of silver phosphate is presented. The technique uses high‐temperature elemental analyzer (EA)‐pyrolysis interfaced in continuous flow (CF) mode to an isotopic ratio mass spectrometer (IRMS). Calibration curves were generated by synthesizing silver phosphate with a 13‰ spread in δ18O values. Calibration materials were obtained by reacting dissolved potassium dihydrogen phosphate (KH2PO4) with water samples of various oxygen isotope compositions at 373 K. Validity of the method was tested by comparing the on‐line results with those obtained by classical off‐line sample preparation and dual inlet isotope measurement. In addition, silver phosphate precipitates were prepared from a collection of biogenic apatites with known δ18O values ranging from 12.8 to 29.9‰ (V–SMOW). Reproducibility of ± 0.2‰ was obtained by the EA‐Py‐CF‐IRMS method for sample sizes in the range 400–500 µg. Both natural and synthetic samples are remarkably well correlated with conventional 18O/16O determinations. Silver phosphate is a very stable material and easy to degas and, thus, could be considered as a good candidate to become a reference material for the determination of 18O/16O ratios of phosphate by high‐temperature pyrolysis. Copyright © 2006 John Wiley & Sons, Ltd.
Use of the gamma distribution to represent monthly rainfall in Africa for drought monitoring applications
Authors: Husak Gregory J. , Michaelsen Joel , Funk Chris
Published: December 2006

Evaluating a range of scenarios that accurately reflect precipitation variability is critical for water resource applications. Inputs to these applications can be provided using location‐ and interval‐specific probability distributions. These distributions make it possible to estimate the likelihood of rainfall being within a specified range. In this paper, we demonstrate the feasibility of fitting cell‐by‐cell probability distributions to grids of monthly interpolated, continent‐wide data. Future work will then detail applications of these grids to improved satellite‐remote sensing of drought and interpretations of probabilistic climate outlook forum forecasts. The gamma distribution is well suited to these applications because it is fairly familiar to African scientists, and capable of representing a variety of distribution shapes. This study tests the goodness‐of‐fit using the Kolmogorov–Smirnov (KS) test, and compares these results against another distribution commonly used in rainfall events, the Weibull. The gamma distribution is suitable for roughly 98% of the locations over all months. The techniques and results presented in this study provide a foundation for use of the gamma distribution to generate drivers for various rain‐related models. These models are used as decision support tools for the management of water and agricultural resources as well as food reserves by providing decision makers with ways to evaluate the likelihood of various rainfall accumulations and assess different scenarios in Africa. Copyright © 2006 Royal Meteorological Society
Inter‐decadal variability in daily rainfall at Durham (UK) since the 1850s
Authors: Burt T. P. , Horton B. P.
Published: December 2006

Records of daily rainfall at Durham (UK) are analysed from 1850 to the present. The most notable wet period is the 1870s, followed by a protracted period of below‐average rainfall. Other than the 1870s, summers tended to be much wetter than winters during the latter part of the 19th century. In the 20th century, summers had become drier and winters wetter. To analyse large daily totals, three thresholds, 15, 22.6, and 25 mm, are used. For all three indices, the frequency of large falls was highest from the 1860s to the 1880s, followed by a low frequency in the 1900s. Since then, the general trend has been for totals to gradually increase. There is a clear division for the annual total rainfall, number of heavy falls (≥15 mm), and proportion of total rainfall provided by heavy falls in the winter (154 mm, 147 days, 12%, respectively) and spring (140 mm, 180 days, 16%) seasons in comparison to the summer (181 mm, 329 days, 28%) and autumn (186 mm, 304 days, 23%) seasons. However, since 1990, winter total rainfall (164 mm) has overtaken the summer total (154 mm). Furthermore, since 1990, heavy falls of rain in spring (23 days) and the proportion of total rainfall (26%) have overtaken summer heavy rain (17 days) and the proportions of rainfall in both summer (24%) and autumn (24%). In terms of heavy rainfall, winters have seen only a small increase in its relative importance, whereas its relative importance declined from the 1960s to the mid‐1990s for summers. The widely recognised increase in the winter:summer ratio of rainfall since the 1960s is clearly evident. Overall, there has been a narrowing of the differences between seasons in terms of the frequency of heavy falls of rain in the 1990s. Copyright © 2006 Royal Meteorological Society
Binary logistic regression models for short term prediction of premonsoon convective developments over Kolkata (India)
Authors: Dasgupta S. , De U. K.
Published: December 2006

Scientists have identified certain dynamic and thermodynamic parameters, which are significant for the occurrence of convective developments in the premonsoon period (March–May) in Kolkata (India). In this paper Binary Logistic Regression Models have been considered for prediction of these convective developments from a prior knowledge of the values of the significant parameters. Analyses have been carried out for lead times of 12 h. Initially the evening radiosonde information (1200 UTC) has been considered as these convective developments occur in Kolkata mostly toward the evening. The performance of the model for similar developments in the morning has also been taken up at a later point. As some of the identified parameters are correlated, the dimension of the problem has been reduced and uncorrelated explanatory variables generated for the Logistic Regression Model. Two conventional variable selection methods, for example, forward and backward selections have been used for this purpose. A comparative study of the two variable selection procedures in the light of the predictive power of the resulting models has been presented. The probable causes underlying the poor performance of the models in case of correct prediction of morning convection over the city has been explored and possible remedies suggested at the end. Copyright © 2006 Royal Meteorological Society
A new quantitative Raman measurement scheme using Teflon as a novel intensity correction standard as well as the sample container
Authors: Nah Sanghee , Kim Donghyuk , Chung Hoeil , Han Sung‐Hwan , Yoon Moon‐Young
Published: December 2006

A novel and reliable quantitative Raman measurement scheme has been proposed for the analyses of ethanol and isopropanol solutions. Teflon tubing was employed as an effective intensity correction standard as well as the sample cell. This allowed for the synchronous collection of the mixed Raman spectrum from the Teflon standard and the sample without any extra optical configuration. A non‐overlapping Teflon band was used as the standard peak to correct the Raman intensity changes resulting from laser power variations. In addition to the use of Teflon tubing,a wide area illumination (WAI) scheme was employed, which made the laser illumination into a circle of 6 mm diameter (area: 28.7 mm2), to cover a wide sample area. The WAI scheme improved the reliability of the Raman measurement by significantly increasing the reproducibility of the sampling owing to a decreased sensitivity to sample placement with respect to the focal plane as well as a wider sample coverage area. The resulting Raman spectra were more reproducible and more representative of the correct sample composition. Overall, a superior prediction performance was achieved using the WAI scheme compared to the conventional Raman collection method. The proposed system has great potential for use in the quantitative analysis of diverse liquid samples with good reproducibility. Copyright © 2006 John Wiley & Sons, Ltd.
Competition between Host Aggregates and Isolated Guest Chromophores in Trapping Excitons in Polybenzazole Copolymers and Blends
Authors: Wang Shanfeng , Chen Yan , Zhuang Qixin , Li Xinxin , Wu Pingping , Han Zhewen
Published: December 2006

Summary: Host–guest systems have been prepared using the blends and copolymers consisting of the host molecule poly(p‐phenylene benzobisoxazole) (PBO) with a higher bandgap of 2.93 eV and the guest molecule poly(2,5‐thienylbenzobisoxazole) (PBOT) with a lower bandgap of 2.57 eV. These systems have been investigated using photoluminescence (PL) spectra and time‐resolved PL decay dynamics. Both PBOT‐PBO copolymers and PBOT/PBO blends with the PBOT compositions less than 20% demonstrate higher intensities and narrower bandwidths in solid‐state emission compared to that of PBOT, as well as larger fractions of the shorter lifetime component in PL decay dynamics. A general scheme on intrachain and interchain exciton migration and trapping mechanism has been proposed to interpret the phenomena in both solutions and thin films. Particularly, a competition in trapping exciton between PBO aggregates and isolated PBOT chromophores has been revealed.

General scheme of exciton migration and trapping paths for host (D: donor)–guest (A: acceptor) systems involving the isolated chromophores (A and D) and aggregates (AA and DD) in both ground state and excited state marked without or with an asterisk.

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General scheme of exciton migration and trapping paths for host (D: donor)–guest (A: acceptor) systems involving the isolated chromophores (A and D) and aggregates (AA and DD) in both ground state and excited state marked without or with an asterisk.
Preparation of Magnetite Nanoparticles Coated with an Amphiphilic Block Copolymer: A Potential Drug Carrier with a Core‐Shell‐Corona Structure for Hydrophobic Drug Delivery
Authors: Bai Yunpeng , Teng Bao , Chen Shizhen , Chang Yu , Li Zhaolong
Published: December 2006

Summary: The synthesis of magnetic magnetite nanoparticles coated with amphiphilic block copolymers of poly(ethyl methacrylate)‐block‐poly(2‐hydroxyethyl methacrylate) for use as new potential carriers for hydrophobic drug delivery is reported. The results show that a new core‐shell‐corona structural material is obtained with a very narrow molecular weight distribution of the hydrophobic segment (PDI = 1.10). UV‐Vis results show that 37% of progesterone is released from the nanoparticles after 22 h, much slower than free release (99% after 14 h), which demonstrates that the presence of the hydrophobic segment can effectively control the release of hydrophobic drugs.

Synthesis of an amphiphilic block polymer poly(ethyl methacrylate)‐block‐poly(2‐hydroxyethyl methacrylate) on magnetite nanoparticles and their use as potential drug carriers

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Synthesis of an amphiphilic block polymer poly(ethyl methacrylate)‐block‐poly(2‐hydroxyethyl methacrylate) on magnetite nanoparticles and their use as potential drug carriers
Redesigning network topology with technology considerations
Authors: Habib Sami J.
Published: December 2006

We present a redesign methodology that automatically redesigns a network topology while considering the different network technology interfaces. The network redesign problem is to preserve as many as possible of the network devices within the original network topology to satisfy the redesign factors while minimizing the redesign cost and time. The redesign factors can be various parameters that are involved in the design of a network topology, such as the workload and number of clients. In this paper we used a uniform growth of the network workload as the main factor for topology redesign; moreover, our methodology attempts to maintain as many as possible of the network devices within the original topology while satisfying the extra growth of the clients' loads. We formulated the network redesign problem as an optimization problem and used an evolutionary approach to search the redesign space. The experimental results for a three‐level network redesign problem described here demonstrate how valuable the redesign methodology is in finding good solutions with low redesign cost and short redesign time for an enterprise networks consisting of 65 client nodes. Copyright © 2006 John Wiley & Sons, Ltd.
Comparison of p16INK4a expression with p53 alterations in head and neck cancer by tissue microarray analysis
Authors: Karsai S , Abel U , Roesch‐Ely M , Affolter A , Hofele C , Joos S , Plinkert PK , Bosch FX
Published: December 2006

We investigated whether there is a relationship between loss of p16INK4a protein expression and p53 alterations in head and neck squamous cell carcinomas (HNSCCs). For this purpose, immunohistochemistry was performed on tissue microarrays of 664 tumours; this represents the largest HNSCC cohort studied for molecular biomarkers. Loss of p16INK4a protein expression was associated with aberrant p53 expression (negative or overexpressed) in the total cohort, and with TP53 mutations in 200 tumours analysed (p < 0.0001 each). Both loss of p16INK4a expression and p53 alterations differed significantly across both tumour sites and stages, being more prevalent in the hypopharynx than in the other tumour sites and in advanced tumour stages. As a possible link between p53 status and p16INK4a loss, we found that increased DNA methyltransferase 1 protein levels occurred preferentially in tumours with aberrant p53 (p = 0.001) and negative p16INK4a expression (p = 0.0004). In the total cohort, there was a borderline significant difference in patient survival across three p16INK4a expression levels (negative, positive, high), with loss of p16INK4a expression showing shortest survival. It is suggested that loss of p16INK4a expression and p53 alterations should be viewed as related events involved in the early carcinogenic process. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Controlled helical orientation of carbazole in amino acid derived poly(N‐propargylamide)s
Authors: Zhao Haichao , Sanda Fumio , Masuda Toshio
Published: December 2006

Novel L‐alanine and L‐glutamic acid derivatized, carbazole‐containing N‐propargylamides [N‐(9‐carbazolyl)ethyloxycarbonyl‐L‐alanine N′‐propargylamide and N‐(9‐carbazolyl)ethyloxycarbonyl‐L‐glutamic acid‐γ‐benzyl ester N′‐propargylamide] were synthesized and polymerized with (nbd)Rh+[η6‐C6H5B−(C6H5)3] (nbd = norbornadiene) as a catalyst to obtain the corresponding polymers with moderate molecular weights in high yields. Polarimetry, circular dichroism, and ultraviolet–visible spectroscopy studies revealed that both poly[N‐(9‐carbazolyl)ethyloxycarbonyl‐L‐alanine N′‐propargylamide] and poly[N‐(9‐carbazolyl)ethyloxycarbonyl‐L‐glutamic acid‐γ‐benzyl ester N′‐propargylamide] took a helical structure with a predominantly one‐handed screw sense in tetrahydrofuran, CHCl3, and CH2Cl2. The helix content of poly[N‐(9‐carbazolyl)ethyloxycarbonyl‐L‐alanine N′‐propargylamide] could be tuned by heat or the addition of a protic solvent, and the helical sense of poly[N‐(9‐carbazolyl) ethyloxycarbonyl‐L‐glutamic acid‐γ‐benzyl ester N′‐propargylamide] was inverted by heat in CHCl3 or in mixtures of tetrahydrofuran and CH2Cl2. Poly[N‐(9‐carbazolyl) ethyloxycarbonyl‐L‐alanine N′‐propargylamide] and poly[N‐(9‐carbazolyl)ethyloxycarbonyl‐L‐glutamic acid‐γ‐benzyl ester N′‐propargylamide] also took a helical structure in film states. They showed small fluorescence in comparison with the monomers and redox activity based on carbazole. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 253–261, 2007
Aging of a donor conjugated polymer: Photochemical studies of the degradation of poly[2‐methoxy‐5‐(3′,7′‐dimethyloctyloxy)‐1,4‐phenylenevinylene]
Authors: Chambon Sylvain , Rivaton Agnès , Gardette Jean‐Luc , Firon Muriel , Lutsen Laurence
Published: December 2006

This article is devoted to the study of the photoaging and thermal aging of poly[2‐methoxy‐5‐(3′,7′‐dimethyloctyloxy)‐1,4‐phenylenevinylene] (MDMO–PPV; also called OC1C10–PPV) used in organic solar cells. Thin MDMO–PPV films (thickness < 1 μm) were exposed to ultraviolet‐light irradiation (λ > 300 nm) in the presence of air or thermooxidized at 60 °C. The modifications of the chemical structure of the matrix were analyzed with ultraviolet–visible and infrared spectroscopy. The oxidation products that formed were identified by postirradiation treatments, including chemical derivatization reactions. On the basis of the identification of the various products formed, a two‐step radical mechanism is proposed to account for the modification of the chemical structure of the polymeric matrix. It involves first the oxidation of the ether substituent followed by the oxidation of the double bonds. These reactions are responsible for a loss of conjugation of MDMO–PPV, chain scissions, and a decrease in the visible absorbance, which are anticipated to drastically impair the photovoltaic properties of the material. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 317–331, 2007
Multiblock copolymers of poly(2,5‐benzophenone) and disulfonated poly(arylene ether sulfone) for proton‐exchange membranes. I. Synthesis and characterization
Authors: Wang Hang , Badami Anand S. , Roy Abhishek , McGrath James E.
Published: December 2006

Nanophase‐separated, hydrophilic–hydrophobic multiblock copolymers are promising proton‐exchange‐membrane materials because of their ability to form various morphological structures that enhance transport. A series of poly(2,5‐benzophenone)‐activated, telechelic aryl fluoride oligomers with different block molecular weights were successfully synthesized by the Ni(0)‐catalyzed coupling of 2,5‐dichlorobenzophenone and the end‐capping agent 4‐chloro‐4′‐fluorobenzophenone. These telechelic oligomers (hydrophobic) were then copolymerized with phenoxide‐terminated, disulfonated poly(arylene ether sulfone)s (hydrophilic) by nucleophilic, aromatic substitution to form hydrophilic–hydrophobic multiblock copolymers. High‐molecular‐weight multiblock copolymers with number‐average block lengths ranging from 3000 to 10,000 g/mol were successfully synthesized. Two separate glass‐transition temperatures were observed via differential scanning calorimetry in the transparent multiblock copolymer films when each block length was longer than 6000 g/mol. Tapping‐mode atomic force microscopy also showed clear nanophase separation between the hydrophilic and hydrophobic domains and the influence of the block length as it increased from 6000 to 10,000 g/mol. Transparent and creasable films were solvent‐cast and exhibited moderate proton conductivity and low water uptake. These copolymers are promising candidates for high‐temperature proton‐exchange membranes in fuel cells, which will be reported separately in part II of this series. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 284–294, 2007