bluuebunny/crossref_metadata_2025_split huggingface dataset:
Education plays a different role in Frontotemporal Dementia and Alzheimer's disease
Authors: Borroni Barbara , Alberici Antonella , Agosti Chiara , Premi Enrico , Padovani Alessandro 
Published: January 2008

AbstractBackgroundThe role of modifiable and non‐modifiable variables in Frontotemporal Dementia (FTD) as compared to Alzheimer's dDisease (AD) and to Progressive Supranuclear Palsy (PSP) or Corticobasal Degeneration Syndrome (CBDS) has not been extensively evaluated. In particular, low education levels have been reported to be a risk factor for AD, but their contribution in FTD is yet not known.ObjectiveTo investigate the role of education, other modifiable and non‐modifiable factors in FTD as compared to AD, PSP and CBDS patients.MethodsOne hundred and seventeen FTD patients, 400 AD, 55 PSP, and 55 CBDS entered the study. Demographic and clinical characteristics were carefully recorded. Age, gender, family history for dementia and Apolipoprotein E (APOE) genotype were considered as non‐modifiable factors; education and comorbidities were included as modifiable variables. Regression analyses were applied in order to identify differences among groups.ResultsFTD differed from AD patients in terms of younger age, positive family history and gender status. In regard to APOE genotype, no differences between FTD and AD were found, but FTD showed higher prevalence of epsilon 4 allele compared to both CBDS and PSP patients (p < 0.05). When modifiable factors were considered, FTD were higher educated than AD patients (p < 0.001). Regression analysis identified younger age, positive family history, and education levels as independently associated variables to FTD diagnosis compared to AD (F = 21.27, R2 = 24.1, p = 0.036).ConclusionOur results highlight that the contribution of education and non‐modifiable factors is likely different in FTD and AD. Further work is needed to completely establish the role of this modifiable variable as a potential area of intervention for dementias. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis of new carbon‐11‐labeled 7‐aroyl‐aminoindoline‐1‐sulfonamides as potential PET agents for imaging of tubulin polymerization in cancers
Authors: Wang Min , Gao Mingzhang , Miller Kathy D. , Sledge George W. , Hutchins Gary D. , Zheng Qi‐Huang 
Published: January 2008

AbstractThe tubulin polymerization is an attractive target for anticancer therapy and in the development of cancer imaging agents for use in biomedical imaging technique positron emission tomography (PET). 7‐Aroyl‐aminoindoline‐1‐sulfonamides are a novel class of potent antitublin agents. Carbon‐11‐labeled 7‐aroyl‐aminoindoline‐1‐sulfonamides have been synthesized as new potential PET agents for imaging of tubulin polymerization in cancers. The target tracers were prepared by O‐[11C]methylation of their corresponding precursors using [11C]CH3OTf and isolated by a simplified solid‐phase extraction purification procedure in 40–55% radiochemical yields based on [11C]CO2 and decay corrected to the end of bombardment (EOB), 15–20 min overall synthesis time from EOB, >98% radiochemical purity, and 74–111 GBq/µmol specific activity at the end of synthesis. Copyright © 2008 John Wiley & Sons, Ltd.
Possible mechanisms of controlling the configuration, stability, and lipophilicity of [99mTcO]N3S and [ReO]N3S chelates
Authors: Su Zifen , Xu Yong 
Published: January 2008

AbstractThe relationship of structural characters of the tripeptidic amine–bisamido‐thiol (N3S type) chelators with the lipophilicity, configuration, and stability of four [99mTcO]N3S and one [ReO]N3S chelates is studied here. The results show that the hydroxymethyl group on the two N3S chelators, RP294 and RP435, has inhibited neither the formation nor interconversion of syn and anti stereoisomers of the chelates, while the tert‐butyl group on RP455 and RP535 has prevented the anti isomer from converting to the syn one both in acidic and neutral solutions. The interconversion rates of a stereoisomer can be accelerated at higher pH. [99mTcO]RP455 is stable in pH 7.4 aqueous solution, while [99mTcO]RP535 undergoes decomposition at the same medium, suggesting the influence of a larger side‐chain on the stability of the chelate. Unlike [99mTcO]RP535, [ReO]RP535 is stable even in 0.1 N NaOH for 3 h without change. Combining factors of medium pH values, nature of substituents on a chelator's backbone, size of side‐chains, and property of central metal ions together determine the lipophilicity, configuration, and stability of [99mTcO]N3S and [ReO]N3S chelates. This information may be useful for a further design of [99mTcO]N3S or [186ReO]N3S or [188ReO]N3S chelates with predictable physicochemical properties favorable for the quality diagnosis of cancers. Copyright © 2008 John Wiley & Sons, Ltd.
Cortical excitability is abnormal in patients with the “fixed dystonia” syndrome
Authors: Avanzino Laura , Martino Davide , van de Warrenburg Bart P. C. , Schneider Susanne A. , Abbruzzese Giovanni , Defazio Giovanni , Schrag Anette , Bhatia Kailash P. , Rothwell John C. 
Published: January 2008

AbstractA form of fixed dystonia (FD) without evidence of basal ganglia lesions or neurodegeneration has been recently characterized (Schrag et al., Brain 2004;127:2360‐2372), which may overlap the clinical spectrum of either complex regional pain syndrome or psychogenic dystonia. Transcranial magnetic stimulation studies in typically mobile dystonia revealed abnormal motor cortical excitability and sensori‐motor integration. We compared 12 patients with limb FD to 10 patients with primary adult‐onset typically mobile dystonia and 11 age‐matched healthy volunteers. Measurements at the first digital interosseus representation area on both hemispheres included: short intracortical inhibition (SICI), contralateral silent period (cSP), and short and long afferent inhibition (SAI and LAI). Repeated measure ANOVA and post‐hoc t‐tests were used for statistical analysis. SICI was significantly reduced in both hemispheres of patients with “typical” and FD, compared to healthy subjects. For both hemispheres, cSP duration was shorter in both fixed and “typical” dystonia patients. SAI and LAI did not significantly differ between the three groups. The abnormal cortical excitability observed in FD might represent an underlying trait predisposing to different clinical forms of dystonia. © 2007 Movement Disorder Society
Patient and caregiver quality of life in Huntington's disease
Authors: Ready Rebecca E. , Mathews Melissa , Leserman Anne , Paulsen Jane S. 
Published: January 2008

AbstractLittle is known about subjective perceptions of quality of life (QOL) in Huntington's disease (HD). The current study determined correlates of patient and caregiver QOL and assessed change over time. Participants were 22 patient‐caregiver dyads, who rated QOL at baseline and 6 months later. Overall, patients' functional and cognitive impairment were significantly correlated with patient and caregiver QOL. Neuropsychiatric symptoms had differential impact on patient and caregiver QOL. Furthermore, when patients recalled their QOL about a previous time, their recall may have been negatively biased. Clinical implications of results are discussed. Future work is needed because subjective QOL is an important outcome measure in therapeutic trials. © 2008 Movement Disorder Society
Analyzing and modeling the inhibitory effect of phosphatidic acid on the GTP‐γ‐S binding activity of Goα
Authors: Qu Liang , Wan Jia , Cao Yu , Zhang Yinghao , Chen Runsheng , Huang Youguo 
Published: January 2008

AbstractG proteins are the molecular switches of G‐protein‐coupled signal transmembrane transduction, which plays a pivotal role in diverse cellular processes. The guanine nucleotide binding states of Gα‐subunits are considered key factors for their functions. We report here that phosphatidic acid (PA) inhibits the [35S]‐GTPγS binding activity of Goα. To elucidate this inhibitory effect, biochemical analyses are carried out and a structure‐based model is proposed. The experimental results show that PA particularly inhibits the activity of the Goα in a dose‐dependent manner, whereas other lipids tested do not. Further analysis on the effects of PA analogs demonstrate that a phosphate head group together with at least one fatty acid chain is necessary for the inhibition. Using a lipid–protein binding assay, it is shown that Goα specifically and directly interacts with PA. In addition to these experimental studies, a 3D structure of Goα is constructed, based on sequence homology greater than 70% to E. coli Giα1. Molecular docking is performed with PA and PA analogs, and the results are compared and analyzed. Collectively, the results of this investigation provide direct experimental evidence for an inhibitory effect of PA on GTP binding activity of Goα, and also suggest a structural model for the inhibitory mechanism. The lipid–protein model suggests that PA may occupy the channel for exchanging guanine nucleotides, thus leading to the inhibition. These findings reveal a potential new drug target for the diseases caused by genetic G‐protein abnormalities. Proteins 2008. © 2008 Wiley‐Liss, Inc.
The 1.38 Å crystal structure of DmsD protein from Salmonella typhimurium, a proofreading chaperone on the Tat pathway
Authors: Qiu Yang , Zhang Rongguang , Binkowski T. Andrew , Tereshko Valentina , Joachimiak Andrzej , Kossiakoff Anthony 
Published: January 2008

AbstractThe DmsD protein is necessary for the biogenesis of dimethyl sulphoxide (DMSO) reductase in many prokaryotes. It performs a critical chaperone function initiated through its binding to the twin‐arginine signal peptide of DmsA, the catalytic subunit of DMSO reductase. Upon binding to DmsD, DmsA is translocated to the periplasm via the so‐called twin‐arginine translocation (Tat) pathway. Here we report the 1.38 Å crystal structure of the protein DmsD from Salmonella typhimurium and compare it with a close functional homolog, TorD. DmsD has an all‐α fold structure with a notable helical extension located at its N‐terminus with two solvent exposed hydrophobic residues. A major difference between DmsD and TorD is that TorD structure is a domain‐swapped dimer, while DmsD exists as a monomer. Nevertheless, these two proteins have a number of common features suggesting they function by using similar mechanisms. A possible signal peptide‐binding site is proposed based on structural similarities. Computational analysis was used to identify a potential GTP binding pocket on similar surfaces of DmsD and TorD structures. Proteins 2008; 71:525–533. Published 2007 Wiley‐Liss, Inc.
The conformational plasticity of calmodulin upon calcium complexation gives a model of its interaction with the oedema factor of Bacillus anthracis
Authors: Laine Elodie , Yoneda Julliane D. , Blondel Arnaud , Malliavin Thérèse E. 
Published: January 2008

AbstractWe analyzed the conformational plasticity of calmodulin (CaM) when it is bound to the oedema factor (EF) of Bacillus anthracis and its response to calcium complexation with molecular dynamics (MD) simulations. The EF‐CaM complex was simulated during 15 ns for three different levels of calcium bound to CaM. They were respectively no calcium ion (EF–(Apo‐CaM)), two calcium ions bound to the C‐terminal domain of CaM (EF–(2Ca‐CaM)), and four calcium ions bound to CaM (EF–(4Ca‐CaM)). Calculations were performed using AMBER package. The analysis of the MD simulations illustrates how CaM forces EF in an open conformation to form the adenylyl cyclase enzymatic site, especially with the two calcium form of CaM, best suited to fit the open conformation of EF. By contrast, CaM encounters bending and unwinding of its flexible interlinker in EF–(Apo‐CaM) and EF–(4Ca‐CaM). Calcium binding to one domain of CaM affects the other one, showing a transmission of information along the protein structure. The analysis of the CaM domains conformation along the simulations brings an atomistic and dynamic explanation for the instability of these complexes. Indeed the EF‐hand helices of the N‐terminal domain tend to open upon calcium binding (EF–(4Ca‐CaM)), although the domain is locked by EF. By contrast, the C‐terminal domain is strongly locked in the open conformation by EF, and the removal of calcium induces a collapse of EF catalytic site (EF–(Apo‐CaM)). Proteins 2008. © 2008 Wiley‐Liss, Inc.
pH sensitivity of type III secretion system tip proteins
Authors: Markham Aaron P. , Birket Susan E. , Picking William D. , Picking Wendy L. , Middaugh C. Russell 
Published: January 2008

AbstractMany pathogenic gram‐negative bacteria employ type III secretion systems to transport proteins into the host cell membrane and cytoplasm to subvert normal cellular functions. The type III secretion apparatus consists of a basal body spanning the inner and outer bacterial membranes and a needle which extends away from the bacterium. Recent work has found that a special class of proteins localizes to the tip of the needle to control secretion of effector proteins. Five of these tip proteins are IpaD (Shigella flexneri), BipD (Burkholderia pseudomallei), SipD (Salmonella spp.), LcrV (Yersinia spp.), and PcrV (Pseudomonas aeruginosa). In this study, the conformational stability of these proteins was characterized as a function of pH and temperature. Understanding the stability of the proteins in different pH environments is particularly important since they are expected to encounter different pH environments in their passage through the gastrointestinal tract and are exposed to low pH microenvironments near the surface of target cell membranes. Secondary and tertiary structural changes were monitored using the spectroscopic techniques of far‐UV circular dichroism, Trp fluorescence, ANS fluorescence, and ultraviolet absorption spectroscopy. Optical density and right angle scattering measurements were also used to evaluate protein association/dissociation. Empirical phase diagrams were then applied to mathematically combine data from the various spectroscopic techniques to provide a global picture of the proteins' structural behavior in solution. The responses of the proteins to changes in temperature and pH conditions reveal two distinct subfamilies in terms of stability. The first is that of IpaD, BipD, and SipD whose corresponding phase diagrams show conformational differences at pH 5–6. The conserved pH dependence in this subfamily suggests possible common mechanistic function. In the second subfamily (LcrV and PcrV), conformational stability is directly related to pH, also indicating mechanistic similarities. Proteins 2008. © 2008 Wiley‐Liss, Inc.
Comparison of the efficiency of evolutionary change‐based and side chain orientation‐based fold recognition potentials
Authors: Vishnepolsky Boris , Managadze Grigol , Pirtskhalava Malak 
Published: January 2008

AbstractThe present article describes residue level knowledge based potential SORDIS. SORDIS incorporates the information on side‐chain orientation in relation to hydrophobic core centres, distance of residue from the globule centre and secondary structure. SORDIS has been tested and compared with widespread evolutionary change‐based substitution matrices (BLOSUM, PAM, GONNET, Johnson‐Overington, BLAJ, HSDM, and STROMA) in fold recognition experiments within the zone of weak sequence similarity (<16%). The obtained results show that the lower is the amino acid similarity between homologous pairs the higher is the performance of SORDIS in comparison with the potentials, based on the information about the evolutionary changes. Therefore, we propose that the employment of SORDIS in fold recognition can be useful. Proteins 2008. © 2008 Wiley‐Liss, Inc.
Complications Associated With Embolization in the Treatment of Blunt Splenic Injury
Authors: Wu Shih‐Chi , Chen Ray‐Jade , Yang Albert D. , Tung Cheng‐Cheng , Lee Kun‐Hua 
Published: January 2008

AbstractBackgroundNonoperative management (NOM) of blunt splenic injuries is widely accepted, and the use of splenic artery embolization (SAE) has become a valuable adjunct to NOM. We retrospectively review and discuss the complications derived from SAE.Materials and methodsThe medical records of 152 consecutive patients with blunt splenic trauma admitted to our trauma center during a 33‐month period were retrospectively reviewed. The patients were managed according to an established algorithm. The record review focused on the method of patient management (operative versus nonoperative) and use of SAE. The complications encountered following SAE are discussed in detail.ResultsAltogether, 73 patients underwent emergency surgery (58 splenectomies, 15 splenorrhaphies), and 79 patients had NOM. Of the 79 patients with NOM, 58 were successfully treated; 2 patients required splenectomy after 24 hours. The remaining 21 patients had SAE, including 18 distal and 3 proximal embolizations. Major complications occurred in 28.5% of the SAE‐treated patients and included total splenic infarction, splenic atrophy, and postprocedure bleeding. Minor complications occurred in 61.9% of the patients and included fever, pleural effusion, and partial splenic infarction.ConclusionSAE is considered a valuable adjunct to NOM in the treatment of blunt splenic injuries; however, risks of major and minor complications do exist, and SAE should be offered with caution and followed up appropriately.
Some Biochemical Properties of Lipase from Bay Laurel (Laurus nobilis L.) Seeds
Authors: Isbilir Sebnem Selen , Ozcan Hakki M. , Yagar Hulya 
Published: January 2008

AbstractLipase was isolated from bay laurel (Laurus nobilis L.) seeds, some biochemical properties were determined. The bay laurel oil was used as the substrate in all experiments. The pH optimum was found to be 8.0 in the presence of this substrate. The temperature optimum was 50 °C. The specific activity of the lipase was found to be 296 U mg protein−1 in optimal conditions. The enzyme activity is quite stable in the range of pH 7.0–10. The enzyme was stable for 1 h at its optimum temperature, and retained about 68% of activity at 60 °C during this time. Km and Vmax values were determined as 0.975 g and 1.298 U mg protein−1, respectively. Also, storage stability and metal effect on lipolytic activity were investigated. Enzyme activity was maintained for 9, 12, and 42 days at room temperature, 4 and −20 °C, respectively. Ca2+, Co2+, Cu2+, Fe2+, and Mg2+ lightly enhanced bay laurel lipase activity.
Sample size and appropriate design of fruit and seed traps in tropical forests
Authors: Stevenson Pablo R. , Vargas Ivonne N. 
Published: January 2008

Abstract:Studies of seed dispersal and fruit production often use fruit traps. Different trap designs may give dissimilar estimates; however, prior to this study there has been no tropical forest field comparison of trap designs. Likewise, there are no recommendations about the number of traps required to assess ecological parameters, such as fruit production, mass and number of seeds dispersed, and number of plant species producing fruits. We compared the effectiveness of five trap designs in terms of fruit/seed bouncing out of traps, wind effects, area effects and seed removal by predators. These studies took place in Colombia in two tropical rain forests and in laboratory conditions. We found that 300 traps (0.085 m2 each) were not enough to obtain stable estimates in two out of four parameters (number of species and dispersed seeds). All estimates were highly variable when using fewer than 100 traps. All trap designs evaluated (mesh on PVC frame, hanging mesh, basin and funnel traps) prevent seed removal by predators, in sharp contrast with removal from the ground. Mesh traps were less affected by bouncing effects than plastic traps, and this factor was a large source of bias among estimates from different traps. Since up to 68% of dry mass may bounce out, it is important to consider adequate trap designs and to be careful when comparing studies using different methodologies. Small traps received fewer seeds per area, however area affects were not evident when bouncing effects were controlled for. We recommend the use of mesh traps on PVC frames, although hanging mesh traps are a good option in tropical forests without strong winds.
Temporal and spatial variability in seedling dynamics: a cross-site comparison in four lowland tropical forests
Authors: Metz Margaret R. , Comita Liza S. , Chen Yu-Yun , Norden Natalia , Condit Richard , Hubbell Stephen P. , Sun I-Fang , Noor Nur Supardi bin Md. , Wright S. Joseph 
Published: January 2008

Abstract:Spatial and temporal variation in seedling dynamics was assessed using records of community-wide seedling demography collected with identical monitoring methods at four tropical lowland forests in Panama, Malaysia, Ecuador and French Guiana for periods of between 3 and 10 y. At each site, the fates of between 8617 and 391 777 seedlings were followed through annual censuses of the 370–1008 1-m2seedling plots. Within-site spatial and inter-annual variation in density, recruitment, growth and mortality was compared with among-site variability using Bayesian hierarchical modelling to determine the generality of each site's patterns and potential for meaningful comparisons among sites. The Malaysian forest, which experiences community-wide masting, was the most variable in both seedling density and recruitment. However, density varied year-to-year at all sites (CVamong years at site= 8–43%), driven largely by high variability in recruitment rates (CV = 40–117%). At all sites, recruitment was more variable than mortality (CV = 5–64%) or growth (CV = 12–51%). Increases in mortality rates lagged 1 y behind large recruitment events. Within-site spatial variation and inter-annual differences were greater than differences among site averages in all rates, emphasizing the value of long-term comparative studies when generalizing how spatial and temporal variation drive patterns of recruitment in tropical forests.
Reliability and validity of the Computerized Comprehension Task (CCT): data from American English and Mexican Spanish infants
Authors: FRIEND MARGARET , KEPLINGER MELANIE 
Published: January 2008

ABSTRACTEarly language comprehension may be one of the most important predictors of developmental risk. The need for performance-based assessment is predicated on limitations identified in the exclusive use of parent report and on the need for a performance measure with which to assess the convergent validity of parent report of comprehension. Child performance data require the development of procedures to facilitate infant attention and compliance. Forty infants (20 at 1 ; 4 and 20 at 1 ; 8) acquiring English completed a standard picture book task and the same task was administered on a touch-sensitive screen. The computerized task significantly improved task attention, compliance and performance. Reliability was high, indicating that infants were not responding randomly. Convergent validity with parent report and 4-month stability was substantial. Preliminary data extending this approach to Mexican-Spanish are presented. Results are discussed in terms of the promise of this technique for clinical and research settings and the potential influences of cultural factors on performance.