bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulating meander evolution of the Geul River (the Netherlands) using a topographic steering model
Authors: Moor J. J. W. de , Balen R. T. van , Kasse C.
Published: January 2007

Active meandering rivers are capable of reworking and removing large quantities of valuable land. Therefore, understanding the characteristics of meandering rivers and predicting future meander behaviour can be of great value for local authorities. In this study, we apply a topographic steering meander model to the Geul River (southern Netherlands), using field data to calibrate the model. The present channel characteristics of the Geul River were mapped in the field. Cut‐banks were classified as erosive, unstable or stable. The model outcomes were compared with these field data.

Several model runs were carried out, using different sets of parameter values. After studying the results and using the field data, we introduced the concept of a variable channel width in the simulation model. In reality, the river has different channel widths varying from 8 to more than 15 m. These widths are a linear function of local curvature. The model runs using a variable channel width show that the model is capable of predicting locations of lateral migration in conformity with observed active lateral migration and erosive banks. With both models, the sediment reworking time of the floodplain can be calculated. Floodplain reworking times of 200–300 years were calculated. In combination with the lateral migration rate, this reworking time is an important element in catchment sediment budget calculations. Copyright © 2007 John Wiley & Sons, Ltd.
The effect of interpolation methods in surface definition: an experimental study
Authors: Yilmaz H. Murat
Published: January 2007

Mappings of the earth surface and their representation in 3D (three‐dimensional) models are commonly used in most recent research. Modeling research, which starts with classical surveying methods, acquires new dimensions matching the modern technologies. 3D models of any object or earth surface can be used in much visual and scientific research. A digital model of the landscape is an important part within creation of geo‐information systems used in the public administration and in the commercial sphere. It is an important tool in applications such as geomorphology, hydrology, geology, cartography, ecology, mining etc.

Values of volume in terrains that do not have regular geometric structure can be obtained more accurately by using 3D models of surfaces with respect to developing technology. Basic data of 3D models must indicate 3D coordinates of the surveyed object in the reference frame. Distribution and intensity of points are important factors in modeling earth surfaces. A minimum number of points is desired in defining an object in 3D. Interpolation methods employing different mathematical models are used to obtain 3D models of terrain surfaces. In this study, the effect of interpolation methods in defining a terrain surface is investigated. For this purpose, a uniform surface, hill‐shaped artificial object with a known volume is employed. The 3D surface and volume are calculated by using 12 different interpolation methods. Point distribution, point intensity and accuracy of point measurements are not considered. The same data set was used for all the interpolation methods. The interpolation methods are compared and evaluated based on the results. Copyright © 2007 John Wiley & Sons, Ltd.
Book reviews
Authors: Hill Matthew G.
Published: January 2007

Folsom: New Archaeological Investigations of a Classic Paleoindian Bison Kill. David J. Meltzer, 2006, University of California Press, Berkeley, California, xiv _ 374 pp., $55.00 (hardcover)
Book reviews
Authors: Mickelson Andrew M.
Published: January 2007

Geographical Information Systems in Archaeology. James Conolly and Mark Lake, 2006, Cambridge University Press, Cambridge, xx + 338 pp., $95.00 ( hardcover), $45.00 (paperback)
The contribution of domestic and external factors to emerging market currency crises: an early warning systems approach
Authors: Kamin Steven B. , Schindler John , Samuel Shawna
Published: January 2007

In this paper, a modified ‘early warning system’ (EWS) approach is developed to identify the roles of domestic and external factors in emerging market crises. Several probit models of currency crises were estimated for 26 emerging market countries. These models were used to identify the separate contributions to the probabilities of crisis of domestic and external variables. We found that, relative to domestic factors, adverse external shocks and large external imbalances contributed little to the average estimated probability of crisis in emerging market countries, but accounted for much more of the spikes in the probability of crisis estimated to occur during actual crisis years. We interpret these results to suggest that while, on average over time, domestic factors have tended to contribute to much of the underlying vulnerability of emerging market countries, adverse swings in external factors may have been important in pushing economies ‘over the edge’ and into currency crisis. In consequence, the costs of giving up exchange rate flexibility through adoption of strongly fixed exchange rate regimes—e.g. currency boards or dollarization—may be quite high for some countries. Published in 2007 by John Wiley & Sons, Ltd.
Activating transcription factor 2 controls Bcl‐2 promoter activity in growth plate chondrocytes
Authors: Ma Qin , Li Xinying , Vale‐Cruz Dustin , Brown Mark L. , Beier Frank , LuValle Phyllis
Published: January 2007

Activating transcription factor 2 (ATF‐2) is expressed ubiquitously in mammals. Mice deficient in ATF‐2 (ATF‐2 m/m) are slightly smaller than their normal littermates at birth. Approximately 50% of mice born mutant in both alleles die within the first month. Those that survive develop a hypochondroplasia‐like dwarfism, characterized by shortened growth plates and kyphosis. Expression of ATF‐2 within the growth plate is limited to the resting and proliferating zones. We have previously shown that ATF‐2 targets the cyclic AMP response element (CRE) in the promoters of cyclin A and cyclin D1 in growth plate chondrocytes to activate their expression. Here, we demonstrate that Bcl‐2, a cell death inhibitor that regulates apoptosis, is expressed within the growth plate in proliferative and prehypertrophic chondrocytes. However, Bcl‐2 expression declines in hypertrophic chondrocytes. The Bcl‐2 promoter contains a CRE at −1,552 bp upstream of the translation start. Mutations within this CRE cause reduced Bcl‐2 promoter activity. We show here that the absence of ATF‐2 in growth plate chondrocytes corresponds to a decline in Bcl‐2 promoter activity, as well as a reduction in Bcl‐2 protein levels. In addition, we show that ATF‐2 as well as CREB, a transcription factor that can heterodimerize with ATF‐2, bind to the CRE within the Bcl‐2 promoter. These data identify the Bcl‐2 gene as a novel target of ATF‐2 and CREB in growth plate chondrocytes. J. Cell. Biochem. 101: 477–487, 2007. © 2007 Wiley‐Liss, Inc.
Regulation of PDGF‐stimulated SHIP2 tyrosine phosphorylation and association with Shc in 3T3‐L1 preadipocytes
Authors: Artemenko Y. , Gagnon A. , Ibrahim S. , Sorisky A.
Published: January 2007

In 3T3‐L1 and human preadipocytes, insulin results in the isolated rise in phosphatidylinositol (PI)‐3,4,5‐P3, whereas PDGF produces PI(3,4)P2 in addition to PI(3,4,5)P3. SH2 domain‐containing inositol 5‐phosphatase 2 (SHIP2) converts PI(3,4,5)P3 into PI(3,4)P2. PDGF, but not insulin, stimulates SHIP2 tyrosine phosphorylation and its association with Shc in human and 3T3‐L1 preadipocytes. We now demonstrate that SHIP2 tyrosine phosphorylation and association with Shc in PDGF‐treated 3T3‐L1 preadipocytes was reduced by bisindolylmaleimide I (BisI), an inhibitor of conventional/novel protein kinase C (PKC). However, the production of PI(3,4)P2 and PI(3,4,5)P3 by PDGF was unaffected by BisI. Activation of PKC by 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) was not sufficient to induce SHIP2 tyrosine phosphorylation. Furthermore, we identified threonine 958 (T958) as a novel PDGF‐responsive SHIP2 phosphorylation site. Mutation of T958 to alanine reduced PDGF‐stimulated SHIP2 tyrosine phosphorylation and association with Shc, but did not alter its anti‐proliferative effect on preadipocytes. This study demonstrates that SHIP2 tyrosine phosphorylation and Shc association can be regulated by serine/threonine signaling pathways, either indirectly (via PKC), or directly (via T958). Interestingly, the anti‐proliferative effect of SHIP2 T958A, as well as another SHIP2 mutant (Y986F, Y987F) that also displays defective tyrosine phosphorylation and Shc association, does not depend on these molecular events. J. Cell. Physiol. 211: 598–607, 2007. © 2007 Wiley‐Liss, Inc.
Tiam1 and βPIX mediate Rac‐dependent endothelial barrier protective response to oxidized phospholipids
Authors: Birukova Anna A. , Malyukova Irina , Mikaelyan Arsen , Fu Panfeng , Birukov Konstantin G.
Published: January 2007

Oxidized 1‐palmitoyl‐2‐arachidonoyl‐sn‐glycero‐3‐phosphorylcholine (OxPAPC) exhibits potent barrier protective effects on pulmonary endothelium, which are mediated by small GTPases Rac and Cdc42. However, upstream mechanisms of OxPAPC‐induced small GTPase activation are not known. We studied involvement of Rac/Cdc42‐specific guanine nucleotide exchange factors (GEFs) Tiam1 and βPIX in OxPAPC‐induced Rac activation, cytoskeletal remodeling, and barrier protective responses in the human pulmonary endothelial cells (EC). OxPAPC induced membrane translocation of Tiam1, βPIX, Cdc42, and Rac, but did not affect intracellular distribution of Rho and Rho‐specific GEF p115‐RhoGEF. Protein depletion of Tiam1 and βPIX using siRNA approach abolished OxPAPC‐induced activation of Rac and its effector PAK1. EC transfection with Tiam1‐, βPIX‐, or PAK1‐specific siRNA dramatically attenuated OxPAPC‐induced barrier enhancement, peripheral actin cytoskeletal enhancement, and translocation of actin‐binding proteins cortactin and Arp3. These results show for the first time that Tiam1 and βPIX mediate OxPAPC‐induced Rac activation, cytoskeletal remodeling, and barrier protective response in pulmonary endothelium. J. Cell. Physiol. 211: 608–617, 2007. © 2007 Wiley‐Liss, Inc.
Interpopulation variation in life‐history traits of Poeciliopsis prolifica: implications for the study of placental evolution
Authors: Pires Marcelo N. , McBride Kevin E. , Reznick David N.
Published: January 2007

Placental reproduction is widespread across vertebrate taxa, but little is known about its life‐history correlates and putative adaptive value. We studied variation in life‐history traits in two populations of the placental poeciliid fish Poeciliopsis prolifica to determine whether differences in post‐fertilization maternal provisioning to embryos have a genetic basis and how food availability affects reproduction. Life histories were characterized for wild‐caught females and for second‐generation lab‐born females raised under two levels of food availability. We found that the two populations did not differ significantly in the wild for any life‐history traits except for the lipid dry weight in females and in embryos at an advanced stage of development. When environmental effects were experimentally controlled, however, populations exhibited significant differences in several traits, including the degree of maternal provisioning to embryos. Food availability significantly affected female size at first parturition, brood size and offspring dry weight at birth. Altogether, these results demonstrate that population differences in maternal provisioning and other life‐history traits have a genetic basis and show a plastic response to food availability. We infer that phenotypic plasticity may mask population differences in the field. In addition, when comparing life‐history patterns in these two populations with known patterns in placental and non‐placental poeciliids, our results support the hypotheses that placentation is an adaptive reproductive strategy under high‐resource conditions but that it may represent a cost under low‐food conditions. Finally, our results highlight that age at maturity and reproductive allotment may be key life‐history traits accompanying placental evolution. J. Exp. Zool. 307A, 2007. © 2007 Wiley‐Liss, Inc.
Erosion of interaction networks in reduced and degraded genomes
Authors: Ochman Howard , Liu Renyi , Rocha Eduardo P.C.
Published: January 2007

Unlike eukaryotes, which often recruit duplicated genes into existing protein–protein interaction (PPI) networks, the low levels of gene duplication coupled with the high probability of lateral transfer of novel genes alters the manner in which PPI networks can evolve in bacteria. By inferring the PPIs present in the ancestor to contemporary Gammaproteobacteria, we were able to trace the changes in gene repertoires, and their consequences on PPI network evolution, in several bacterial lineages that have independently undergone reductions in genome size and genome contents. As genomes degrade, virtually all multi‐partner proteins have lost interactors; however, the overall average number of connections increases due to the preferential elimination of proteins that interact with only one other protein partner. We also studied the effect of lateral gene transfer on PPI network evolution by analyzing the connectivity of genes that have been gained along the Escherichia coli lineage, as well as those acquired genes subsequently silenced in Shigella flexneri, since diverging from the gammaproteobacterial ancestor. The situation in PPI networks, in which newly acquired genes preferentially attach to the hubs of the network, contrasts that observed in metabolic networks, which evolve by the peripheral gain and loss of genes, and in regulatory networks, in which high connectivity increases the propensity of loss. J. Exp. Zool. (Mol. Dev. Evol.) 308B, 2007. © 2007 Wiley‐Liss, Inc.
Explaining the freemartin: Tandler and Keller vs. Lillie and the question of priority
Authors: Freeman Gary
Published: January 2007

The correct explanation for the freemartin phenotype in the female twin of a female–male pair in cattle was first reported by Tandler and Keller (1911. Deutsche Tierärzt Wochenschr 19:148–149). This same explanation for the freemartin was independently discovered by Lillie (1916. Science 43:611–613). Today both set of scientists are given credit for this discovery; it is the basis for much of the subsequent work on the developmental basis for sex differentiation in vertebrates. Even though Lillie published after Keller and Tandler, he gets credit for this discovery because: (1) Keller and Tandler published in a veterinary journal and as a consequence their work was not disseminated as broadly throughout the larger scientific community; this problem was compounded by the fact that their definitive 1916 paper was published under wartime conditions during World War I, and (2) Lillie was an influential scientist with a group of graduate students who could elaborate on and extend his work; they published a number of papers on the freemartin. At some point while Lillie was doing his initial work on the freemartin he may have become aware that Keller and Tandler were also working on the freemartin problem; this information may have shaped his decision on when to publish. J. Exp. Zool. (Mol. Dev. Eiol.) 308B, 2007. © 2007 Wiley‐Liss, Inc.
Maternal control of pattern formation in Xenopus laevis
Authors: White Jody A. , Heasman Janet
Published: January 2007

We review the essential role of maternal factors in pattern formation for Xenopus laevis, focusing on VegT, Vg1, and Wnt11. Results from loss of function experiments demonstrate a clear requirement for these genes in germ layer specification, dorsal–ventral axis formation, and convergence extension. We also discuss these genes in the broader context of metazoan development, exploring whether and how their functions in the X. laevis model organism may or may not be conserved in other species. Wnt11 signaling in particular provides a classic example where understanding context in development is crucial to understanding function. Genomic sequencing, gene expression, and functional screening data that are becoming available in more species are providing invaluable aid to decoding and modeling signaling pathways. More work is needed to develop a comprehensive catalog of the Wnt signaling, T‐box, and TGF‐β genes in metazoans both near and far in evolutionary distance. We finally discuss some specific experimental and modeling efforts that will be needed to understand the behavior of these signaling networks in vivo so that we can interpret these critical pathways in an evolutionary framework. J. Exp. Zool. (Mol. Dev. Evol.) 310B:73–84, 2008. © 2007 Wiley‐Liss, Inc.
Serum cytokine levels in response to hepatic cryoablation
Authors: Osada Shinji , Imai Hisashi , Tomita Hiroyuki , Tokuyama Yasuharu , Okumura Naoki , Matsuhashi Nobuhisa , Sakashita Fumio , Nonaka Kenichi
Published: January 2007

Background and Objectives

Cryogenic treatment sometimes stimulates the immune system by releasing intracellular antigens. We evaluated anti‐tumor immune response by analyzing alterations in serum cytokine levels.

Methods

Percutaneous cryosurgery was performed in 13 patients with unresectable tumors. Serum levels of interleukin (IL) ‐4, ‐6, and ‐10, tumor necrosis factor (TNF)‐alpha, and interferon (IFN)‐gamma were measured by enzyme‐linked immunosorbent assay (ELISA). The Th1/Th2 ratio was estimated from the IFN‐gamma/IL‐4 ratio.

Results

Levels of serum factors in the immune reaction (IR) group, in which tumor necrosis was identified not only in the treated area but also away from the treated area, were compared with those in the local effect (LE) group. Serum amyloid A (SAA), C‐reactive protein (CRP), and IL‐6 levels were increased in both groups after three treatments. The serum IL‐10 level tended to increase with the number of treatments. Pretreatment IL‐10 levels in the LE group were significantly greater than those in the IR group, and the maximum value in the LE group (59.5 ± 13.2 pg/ml) was greater than that in the IR group (47.0 ± 15.0 pg/ml). The TNF‐alpha level was increased in the IR group. Pretreatment TNF‐alpha levels and maximum levels in response to treatment were significantly greater in the IR group than in the LE group (P = 0.0313). The Th1/Th2 ratio was increased in the IR group, and the maximum ratio was significantly greater in the IR group than in the LE group.

Conclusion

It might be possible to evaluate the appearance of immune responses to cryosurgery by monitoring serum cytokine levels. J. Surg. Oncol. 2007; 95: 491–498. © 2007 Wiley‐Liss, Inc.
Germline MYH mutations in a clinic‐based series of Canadian multiple colorectal adenoma patients
Authors: Croitoru Marina E. , Cleary Sean P. , Berk Terri , Di Nicola Nando , Kopolovic Ilana , Bapat Bharati , Gallinger Steven
Published: January 2007

Objectives

MYH is a member of the DNA base excision repair (BER) pathway and mutations of this gene predispose to the development of colorectal neoplasia in an autosomal recessive transmission pattern. Our objective was to determine the significance of MYH mutations in a series of Canadian patients with multiple adenomas.

Methods

We screened for germline MYH mutations (by dHPLCO) in 20 clinic‐based multiple adenoma patients who were adenomatous polyposis coli (APC) mutation‐negative. Suspected mutations were confirmed by sequence analysis.

Results

Six of 20 (30%) patients carried pathogenic biallelic MYH mutations, 1 Y165C homozygote and 5 compound heterozygotes of other sequence variants. We identified three novel variants, Q377X, 1314delA, and P281L, which are likely pathogenic. Twenty‐nine relatives of the Y90X/1103delC compound heterozygous carrier were also screened for germline MYH mutations, and 1 homozygous and 14 heterozygous carriers were identified.

Conclusions

Among patients with multiple adenomas, biallelic MYH mutations account for approximately 30% of APC mutation negative cases and two thirds of these carry mutations other than the “common” Y165C and G382D variants. Clinical screening algorithms which focus only on the Y165C and G382D alleles are inadequate since additional pathogenic mutations may be identified by screening the entire gene. J. Surg. Oncol. 2007; 95: 499–506. © 2007 Wiley‐Liss, Inc.
Cyclooxygenase‐2 expression is critical for chronic UV‐induced murine skin carcinogenesis
Authors: Fischer Susan M. , Pavone Amy , Mikulec Carol , Langenbach Robert , Rundhaug Joyce E.
Published: January 2007

While it has been established that both the constitutive and inducible forms of cyclooxygenase (COX‐1 and COX‐2, respectively) play important roles in chemical initiation‐promotion protocols with phorbol ester tumor promoters, the contribution of these two enzymes to ultraviolet (UV) light‐induced skin tumors has not been fully assessed. To better understand the contribution of COX‐1 and COX‐2 to UV carcinogenesis, we transferred the null allele for each isoform onto the SKH‐1 hairless strain of mouse. Due to low viability on this background with complete knockout of COX‐2, heterozygous mice were used in UV carcinogenesis experiments. While the lack of one allele of COX‐1 had no effect on tumor outcome, the lack of one allele of COX‐2 resulted in a 50–65% reduction in tumor multiplicity and a marked decrease in tumor size. Additionally, transgenic SKH‐1 mice that overexpress COX‐2 under the control of a keratin 14 promoter developed 70% more tumors than wild‐type SKH‐1 mice. The lack of one allele of either COX‐1 or COX‐2 reduced prostaglandin (PG) E2 levels in response to a single UV treatment. The proliferative response to UV was significantly reduced in COX‐2, but not COX‐1, heterozygous mice. UV‐induced apoptosis, however, was greater in COX‐2 heterozygous mice. Collectively, these results clearly establish the requirement for COX‐2 in the development of skin tumors. © 2007 Wiley‐Liss, Inc.
Mouse skin chemical carcinogenesis is inhibited by antizyme in promotion‐sensitive and promotion‐resistant genetic backgrounds
Authors: Feith David J. , Shantz Lisa M. , Shoop Paula L. , Keefer Kerry A. , Prakashagowda Chethana , Pegg Anthony E.
Published: January 2007

Elevated polyamine content and increased ornithine decarboxylase (ODC) activity have been associated with neoplastic growth in numerous animal models and human tissues. Antizyme (AZ) is a negative regulator of polyamine metabolism that inhibits ODC activity, stimulates ODC degradation, and suppresses polyamine uptake. Preliminary evidence, obtained from transgenic mice with tissue specific overexpression of AZ indicates that tumor development can be suppressed by AZ. To extend these studies, we have examined the effect of keratin 5 (K5)‐ or K6‐driven AZ transgenes on 7,12‐dimethylbenz[a]anthracene (DMBA)/12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) chemical carcinogenesis of the skin, in promotion‐resistant C57BL/6 and promotion‐sensitive DBA/2 mice. On both genetic backgrounds, K6‐AZ mice showed a reduction in tumor multiplicity, with 85% fewer tumors than wild‐type controls on the C57BL/6 background and 50% fewer tumors on the DBA/2 background. K5‐AZ mice developed 50% fewer tumors than controls on both backgrounds. The percent of mice with tumors and tumor size were also reduced in the K5‐AZ and K6‐AZ groups. Tumor and TPA‐treated skin sections from K6‐AZ mice exhibited the strongest AZ expression, with localization mainly in suprabasal keratinocytes. K6‐AZ mice also had slightly reduced cell proliferation rates in tumors and TPA‐treated skin. The lack of a more pronounced effect on cell proliferation is probably explained by the observation that AZ staining did not colocalize with proliferating cell nuclear antigen (PCNA), a marker for the proliferative compartment. These studies demonstrate a tumor‐suppressive effect of AZ in C57BL/6 and DBA/2 mice, and confirm the importance of ODC and polyamines in tumor development. © 2007 Wiley‐Liss, Inc.
Potentiation of chemotherapeutics by the Hsp90 antagonist geldanamycin requires a steady serum condition
Authors: Burkitt Michael , Magee Conor , O'Connor David , Campbell Fiona , Cornford Philip , Greenhalf William
Published: January 2007

Inhibition of Hsp90 potentiates diverse chemotherapeutics, but it is not clear if this applies only to specific agents, tumor types or conditions. The aim of this report is to determine the effect of serum starvation (SS) on potentiation. SUIT2 cells were cultured with and without the presence of serum and 3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyltetrazolium bromide (MTT) assays were carried out at time intervals. Cytotoxic agents were added individually or in combination. Immunohistochemistry of tumor samples and immunofluorescence of cultured cells were used to examine Hsp90 localization. In the presence of serum an at least additive effect of combining the Hsp90 inhibitor geldanamycin (GA) with 5‐fluorouracil (5FU) was demonstrated. Following pretreatment with GA, 5FU and GA were synergistic. However, during SS GA was protective against 5FU. Geldanamycin also protected cells from 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) during SS. Protection of cells is transitory, as after 24 h of SS GA again has an at least additive negative effect on vitality with 5FU or TPA. Serum starvation of pancreatic cancer cell lines causes normally largely cytoplasmic Hsp90 to become predominantly nuclear localized. Hsp90 nuclear localization was observed in pancreatic and prostate tumors. Hsp90 binding to a pro‐apoptotic client could explain the transitory protection of cells by Hsp90 inhibition during SS. Although potentiation of chemotherapeutics by Hsp90 inhibition is probably a general phenomenon, design of clinical trials should take into account that continuous co‐administration may be ineffective because of a balance of synergy of the drugs in some cells and mutual inhibition of the two drug activities in other cells. © 2007 Wiley‐Liss, Inc.
Pathogenicity of the Lrrk2 R1514Q substitution in Parkinson's disease
Authors: Toft Mathias , Mata Ignacio F. , Ross Owen A. , Kachergus Jennifer , Hulihan Mary M. , Haugarvoll Kristoffer , Stone Jeremy T. , Blazquez Marta , Gibson J. Mark , Aasly Jan O. , White Linda R. , Lynch Timothy , Adler Charles H. , Gwinn‐Hardy Katrina , Farrer Matthew J.
Published: January 2007

An increasing number of nonsynonymous LRRK2 variants are being reported as putative pathogenic mutations. We identified one large kindred harboring the Lrrk2 R1514Q substitution; however, the variant did not segregate fully with disease. Combined analyses of three case–control series demonstrate that the R1514Q substitution is not associated with increased risk of disease (OR: 1.3; 95% CI: 0.6–2.8; P = 0.45). These findings highlight the importance of using family‐based studies and multiple population screenings when examining the association of these polymorphic LRRK2 gene variants with Parkinson's disease. © 2007 Movement Disorder Society
Quality of life in focal, segmental, and generalized dystonia
Authors: Page Donna , Butler Anthony , Jahanshahi Marjan
Published: January 2007

The objective of this study was to assess quality of life (QoL) in a community‐based sample of people with various forms of dystonia and to identify the factors that predict QoL in dystonia. QoL was assessed using two generic questionnaires: the Medical Outcomes Study Short‐Form 36 (SF36) and the EuroQol questionnaire. A host of demographic, clinical, and psychosocial variables were measured to identify the best predictors of QoL in dystonia. A comparison of EuroQol and SF36 scores with the norms for the general UK population of similar age showed that people with dystonia had scores indicative of worse QoL on all domains, particularly those related to physical and social functioning. The impairment of QoL was seen in all age groups and was similar for men and women. Compared to the focal dystonia group, participants with generalized dystonia scored significantly worse on all QoL measures. Participants who were unemployed also scored significantly worse. There was also a trend for younger and separated/divorced participants to score worse on QoL measures. A stepwise regression analysis revealed that functional disability, body concept, and depression were important predictors of QoL in dystonia. Dystonia influences various aspects of QoL, particularly those related to physical and social functioning. The impairment of QoL was greater for participants with generalized dystonia, those who were unemployed, younger, and separated/divorced. Functional disability, body concept, and depression were the best predictors of QoL in dystonia. Efforts to improve health care for people with dystonia should not only focus on management of the movement disorder but also consider modifying functional disability and negative body concept and depression that contribute to poor QoL in this disorder. © 2006 Movement Disorder Society
Rett syndrome: An overlooked diagnosis in women with stereotypic hand movements, psychomotor retardation, Parkinsonism, and dystonia?
Authors: Roze Emmanuel , Cochen Valérie , Sangla Sophie , Bienvenu Thierry , Roubergue Anne , Leu‐Semenescu Smaranda , Vidaihet Marie
Published: January 2007

Rett syndrome is an X‐linked neurodevelopmental disorder resulting in profound psychomotor retardation. It is usually diagnosed by a pediatrician or pediatric neurologist. Adult neurologists may, therefore, overlook the possibility of Rett syndrome in women with psychomotor retardation of unknown etiology. We report the case of a woman diagnosed with Rett syndrome at age 49 years. This report emphasizes the diagnostic value of movement disorders, including hand stereotypies, Parkinsonism, and dystonia, in adults with Rett syndrome. © 2006 Movement Disorder Society
Local field potentials and oscillatory activity of the internal globus pallidus in myoclonus–dystonia
Authors: Foncke Elisabeth M.J. , Bour Lo J. , Speelman Johannes D. , Koelman Johannes H.T.M. , Tijssen Marina A.J.
Published: January 2007

The pathophysiology of myoclonus–dystonia (M–D), an autosomal dominantly inherited movement disorder characterized by myoclonic jerks and dystonic contractions, is largely unknown. In the present study, local field potential (LFP) activities in the globus pallidus internus (GPi) from two genetically proven M–D patients are investigated. Coherence analysis between GPi LFP activity and electromyographic muscle activity (EMG) and synchronization of GPi neuronal activity using event‐related spectral perturbation (ERSP) in a go–no‐go paradigm were studied. Significant increased coherence in the 3 to 15 Hz frequency band was detected between GPi LFP activity and several muscles, with the LFP leading the muscles. The ERSP analysis revealed synchronization in the 3 to 15 Hz frequency band within the GPi before the imperative cue of the go–no‐go task and desynchronization in the same band after the cue. The LFP recordings of the GPi in M–D show that the low‐frequency band previously described in dystonia is also involved in the dystonia plus syndrome M–D. The 3 to 15 Hz synchronization in the go–no‐go paradigm has not been described previously and may point to the existence of (myoclonus–)dystonia specific oscillatory activity in the GPi. © 2006 Movement Disorder Society
Magnetic resonance spectroscopic evidence for presupplementary motor area neuronal dysfunction in Parkinson's disease
Authors: Camicioli Richard M. , Hanstock Christopher C. , Bouchard Thomas P. , Gee Myrlene , Fisher Nancy J. , Martin W.R. Wayne
Published: January 2007

The anterior cingulate (AC) gyrus and the presupplementary motor area (pre‐SMA) show pathological changes in Parkinson's disease (PD). We examined if PD patients show magnetic resonance spectroscopy (MRS) changes in NAA/Cr in the AC, pre‐SMA, or posterior cingulate (PC). Forty‐four (27 male, 17 female) healthy nondemented PD patients and 38 controls (18 male, 20 female) 65 years of age and older were examined using the Unified Parkinson's Disease Rating Scale (UPDRS), Mini‐Mental State Examination, Frontal Assessment Battery, and Geriatric Depression Scale. MRS was performed at 1.5 T. Voxels (8 cc; PRESS; TE = 80; TR = 1,600 ms) were placed mid‐sagittally. Gray matter and white matter volumes were measured within voxels using SPM2. Spectra were analyzed using LC model to yield NAA/Cr and Cho/Cr. Demographic and cognitive measures did not differ between groups. Motor UPDRS was 17.7 ± 8.8 for PD. Pre‐SMA NAA/Cr was lower in PD (PD: 1.39 ± 0.17; control: 1.47 ± 0.16; P = 0.045) and correlated negatively with age (r = 0.39; P = 0.01), but not with UPDRS, disease duration, or dopamine equivalents. AC and PC NAA/Cr and Cho/Cr in any region did not differ (P > 0.05). In conclusion, pre‐SMA NAA/Cr was selectively decreased in PD, consistent with neuronal dysfunction. This should be further examined as a biomarker of disease in PD. © 2006 Movement Disorder Society
Altered mRNA expression patterns in bovine blastocysts after fertilisation in vitro using flow‐cytometrically sex‐sorted sperm
Authors: Morton K.M. , Herrmann D. , Sieg B. , Struckmann C. , Maxwell W.M.C. , Rath D. , Evans G. , Lucas‐Hahn A. , Niemann H. , Wrenzycki C.
Published: January 2007

Sperm‐sexing has been used to produce embryos and offspring of a pre‐determined sex in a number of species. However, the fertility of sex‐sorted sperm is reduced and the full effects of sperm‐sexing remain to be elucidated. The purpose of the present study was to investigate the potential effects of sex‐sorted sperm on mRNA expression patterns of developmentally important genes employing in vitro produced bovine embryos. Bovine embryos were produced in vitro with unsorted and sex‐sorted sperm and mRNA expression patterns were determined for glucose‐3 transporter (Glut‐3), glucose‐6‐phosphate dehydrogenase (G6PD), X‐inactive specific transcript (X‐ist) and Heat shock protein 70.1 (Hsp) using semi‐quantitative endpoint reverse transcriptase‐PCR in male and female, day‐7 and 8 embryos. The relative abundance (RA) of Glut‐3 was higher for day‐7 male than female embryos, and day‐7 embryos derived from unsorted compared with sex‐sorted sperm. The RA of G6PD was higher for embryos derived from unsorted than sex‐sorted sperm, and for day‐8 female compared with male embryos. The RA of Xist was higher for female than male embryos, and for day‐7 female embryos derived from unsorted than sex‐sorted sperm. Hsp RA was higher for female compared with male embryos, was similar for day‐7 and 8 embryos, and unsorted and sex‐sorted sperm derived embryos. These results demonstrate differential expression of developmentally important genes between male and female embryos, and embryos derived from unsorted and sex‐sorted sperm. Mol. Reprod. Dev. 74: 931–940, 2007. © 2007 Wiley‐Liss, Inc.
Expression of follicle stimulating hormone and luteinizing hormone receptors during follicular growth in the domestic cat ovary
Authors: Saint‐Dizier Marie , Malandain Elise , Thoumire Sandra , Remy Benoit , Chastant‐Maillard Sylvie
Published: January 2007

In order to better understand the pituitary regulation of follicular growth in the domestic cat, follicle stimulating hormone (FSH) and luteinizing hormone (LH) receptors (R) were localized and quantified in relation to follicle diameter and atresia using in situ ligand binding on ovarian sections. Expression of FSHR was homogeneous and restricted to follicle granulosa cells from the early antral stage onwards, whereas expression of LHR was heterogeneous on theca cells of all follicles from the early antral stage onward, and homogeneous on granulosa cells of healthy follicles larger than 800 µm in diameter and in corpora lutea. LHR were also widely expressed as heterogeneous aggregates in the ovarian interstitial tissue. Atretic follicles exhibited significantly reduced levels of both FSHR and LHR on granulosa cells, compared with healthy follicles whatever the follicular diameter, whereas levels of LHR on theca cells were lower only for atretic follicles larger than 1,600 µm in diameter. In healthy follicles, levels of FSHR and LHR in all follicular compartments increased significantly with diameter. Although generally comparable to that observed in other mammals, the expression pattern of gonadotropin receptors in the cat ovary is characterized by an early acquisition of LHR on granulosa cells of growing follicles and islets of LH binding sites in the ovarian interstitial tissue. Mol. Reprod. Dev. 74: 989–996, 2007. © 2007 Wiley‐Liss, Inc.
Determining Rayleigh damping parameters of soils for finite element analysis
Authors: Ju Shen‐Haw , Ni Sheng‐Huoo
Published: January 2007

Soil damping ratio is an important parameter for modelling the dynamic behaviour of soil embankment structures, especially for the micro‐vibration analysis of hospitals and high‐tech industries, which have a very severe construction requirement for vibration. This paper explores using a least‐squares method to evaluate the Rayleigh damping parameters for the finite element analysis of wave propagation in soils. The least‐squares method was first used in Bornitz's equation to calculate the absorption coefficients of soils. Afterward, the best‐fit Rayleigh damping parameters were obtained using those coefficients in the least‐squares scheme again. Both three‐dimensional finite element analyses and field experiments were performed to validate the accuracy of this method. The comparison between experimental and finite element results demonstrates that the accuracy of this least‐squares method is acceptable. Copyright © 2007 John Wiley & Sons, Ltd.
Application of enhanced assumed strain finite element method to predict collapse loads of undrained geotechnical problems
Authors: Zhou X. X. , Chow Y. K. , Leung C. F.
Published: January 2007

Many low‐order displacement‐based finite elements with exact integration are not suitable for estimating collapse loads of undrained geotechnical problems, especially for axisymmetric cases. As a result, higher‐order elements have to be used for these situations. In this technical note, the enhanced assumed strain (EAS) finite element method proposed by Simo and Rifai for elasticity problems are extended to plasticity problems to determine collapse loads. The numerical results for the problem of a smooth rigid surface footing on a deep purely cohesive undrained soil layer are given. It is demonstrated that the four‐noded quadrilateral EAS finite element is capable of estimating the collapse loads accurately for both undrained plane strain and axisymmetric problems. Copyright © 2007 John Wiley & Sons, Ltd.
Bladder outlet obstruction index and maximal flow rate during urodynamic study as powerful predictors for the detection of urodynamic obstruction in women
Authors: Gravina Giovanni Luca , Costa Alessia Mariagrazia , Ronchi Piero , Paradiso Galatioto Giuseppe , Gualà Luana , Vicentini Carlo
Published: January 2007

Aims

To evaluate whether bladder outlet obstruction index (BOOI), a mathematical index of outlet resistance, in association with maximal flow rate (Qmax) obtained during multichannel urodynamics (UDS) or detrusor pressure at maximal flow rate (PdetQmax) could help the identification of obstruction in women.

Methods

From January 2004 to February 2005, 401 women were assessed in our urodynamic unit. Of these, 133 were neurologically intact women, referred symptoms suggestive of voiding disorders and had an abnormal non‐intubated uroflussometry (NIF) (BOO group). A normal NIF was defined as a bell‐shaped curve in presence of a Qmax >15 ml/sec and a PVR <50 ml. Symptoms of voiding disorders were ascertained by interview and rated positive if they occurred more than occasionally. Thirty‐seven women were enrolled as unobstructed if they presented a normal NIF and symptoms suggestive of voiding disorders less than occasionally (unobstructed group).

Results

ROC curve demonstrated similar diagnostic accuracy in the diagnosis of urodynamic obstruction for Qmax obtained during UDS (AUC = 0.908; P < 0.0001; CI99% = 0.831 to 0.985) and BOOI (AUC = 0.879; P < 0.0001; CI99% = 0.794 to 0.918) and the least was seen for PdetQmax (AUC = 0.706; P = 0.001; CI99% = 0.620 to 0.830). A Qmax obtained during UDS cut‐off ≤15 ml/sec provides specificity of 85.9% and sensitivity of 78.9%. A BOOI cut‐off ≥−8 provides a sensitivity of 80.8% and specificity of 86.1%. The weakest sensitivity (64.2%) and specificity (64.6%) was recorded for PdetQmax ≥28 cmH2O.

Conclusions

BOOI and Qmax obtained during UDS appears to be the most discriminating urodynamic parameters of female BOO. The use of these cutoff might facilitate the identification of women with functional and anatomical obstruction. Neurourol. Urodynam. 26:247–253, 2007. © 2007 Wiley‐Liss, Inc.
Performance evaluation of distributed multiple home agents with HAHA protocol
Authors: Lee Jong‐Hyouk , Chung Tai‐Myoung
Published: January 2007

Mobile IPv6 (MIPv6) is a protocol that supports mobility of mobile nodes (MNs) within the IPv6 environment. However, the current MIPv6 supports insufficient mobility of MNs. If an MN is moved away from the home link, it takes time for the MN to make a registration and binding update at the home agent (HA). Moreover, the Dynamic Home Agent Address Discovery (DHAAD) mechanism in MIPv6 is too slow for the MN to recover when its HA fails. To solve these two problems, we propose a Distributed Multiple Home Agents (DMHA) scheme. This scheme allows an MN to perform a binding update with the nearest HA, so that the delay in the binding update process can be reduced. It also reduces the fault rate of handoff up to about 55.5% based on the same network parameters. Numerical results presented in this paper show that our scheme has superior performance compared to the standard scheme. Copyright © 2007 John Wiley & Sons, Ltd.
Stabilized rounded addition of hierarchical matrices
Authors: Bebendorf M. , Hackbusch W.
Published: January 2007

The efficiency of hierarchical matrices is based on the approximate evaluation of usual matrix operations. The introduced approximation error may, however, lead to a loss of important matrix properties. In this article we present a technique which preserves the positive definiteness of a matrix independently of the approximation quality. The importance of this technique is illustrated by an elliptic mixed boundary value problem with tiny Dirichlet part. Copyright © 2007 John Wiley & Sons, Ltd.
XFEM‐based crack detection scheme using a genetic algorithm
Authors: Rabinovich Daniel , Givoli Dan , Vigdergauz Shmuel
Published: January 2007

A new computational tool is developed for the accurate detection and identification of cracks in structures, to be used in conjunction with non‐destructive testing of specimens. It is based on the solution of an inverse problem. Based on some measurements, typically along part of the boundary of the structure, that describe the response of the structure to vibration in a chosen frequency or a combination of frequencies, the goal is to estimate whether the structure contains a crack, and if so, to find the parameters (location, size, orientation and shape) of the crack that produces a response closest to the given measurement data in some chosen norm. The inverse problem is solved using a genetic algorithm (GA). The GA optimization process requires the solution of a very large amount of forward problems. The latter are solved via the extended finite element method (XFEM). This enables one to employ the same regular mesh for all the forward problems. Performance of the method is demonstrated via a number of numerical examples involving a cracked flat membrane. Various computational aspects of the method are discussed, including the a priori estimation of the ill‐posedness of the crack identification problem. Copyright © 2007 John Wiley & Sons, Ltd.
Implementation aspects of the bridging scale method and application to intersonic crack propagation
Authors: Farrell David E. , Park Harold S. , Liu Wing Kam
Published: January 2007

The major purpose of this work is to investigate the performance of the bridging scale method (BSM), a multiscale simulation framework for the dynamic, concurrent coupling of atomistics to continua, in capturing shear‐dominant failure. The shear‐dominant failure process considered in this work is intersonic crack propagation along a weak plane in an elastic material, similar to the seminal molecular dynamics (MD) simulations by Abraham and Gao (Phys. Rev. Lett. 2000; 84(14):3113–3116). We show that the BSM simulations accurately capture the essential physics of the intersonic crack propagation, including the formation of a daughter crack and the sudden acceleration of the crack to a velocity exceeding the material shear wave speed. It is also demonstrated that the non‐reflecting boundary condition can adequately dissipate the strongly localized wave formed by the Mach cone after the crack accelerates beyond the material shear wave speed. Finally, we provide the algorithm for our implementation of the BSM, as well as the code used to determine the damping kernels via a newly adopted technique which is less expensive than previous methods. Copyright © 2007 John Wiley & Sons, Ltd.
Optimism and life events as predictors of fear appraisals in mothers of children undergoing hematopoietic stem cell transplantation
Authors: DuHamel Katherine N. , Rini Christine , Austin Jane , Ostroff Jamie , Parsons Susan , Martini Richard , Williams Sharon , Mee Laura , Sexson Sandra , Winkel Gary , Boulad Farid , Redd William H. , Manne Sharon
Published: January 2007

Although mothers' fear appraisals about their child's future health and well‐being affect their own psychological adjustment to their child's hematopoietic stem cell transplantation (HSCT), little is known about antecedents of maternal fear appraisals. This longitudinal study investigated several potential antecedents of these fear appraisals: maternal optimism, recent negative life events, lifetime history of traumatic events, and medical characteristics of the child's disease and HSCT course. One hundred‐forty mothers were interviewed during their child's hospitalization for HSCT and at 3‐and 6‐months post‐HSCT. Structural equation modeling was used to test a model of hypothesized relations. Consistent with predictions, lower optimism and a greater number of negative life events were independently associated with greater maternal fear appraisals. Contrary to expectations, lifetime history of trauma was not associated with maternal fear appraisals. Mothers' fear appraisals during their child's hospitalization were, in turn, associated with their fear appraisals up to 6 months later. These data identify a subset of mothers who may be particularly in need of an intervention to increase optimistic coping strategies, improve coping with negative life events, and reduce fear appraisals to improve their adjustment following their child's HSCT. Copyright © 2007 John Wiley & Sons, Ltd.
Investigation of an albumin‐enriched fraction of human serum and its albuminome
Authors: Gundry Rebekah L. , Fu Qin , Jelinek Christine A. , Van Eyk Jennifer E. , Cotter Robert J.
Published: January 2007

The removal of albumin and other high abundance proteins is a routine first step in the analysis of serum and plasma proteomes. However, as albumin can bind proteins and peptides, there is a universal concern as to how the serum proteome is changed by the removal of albumin. To address this concern, the current study was designed to identify proteins and peptides removed from the serum during albumin depletion; to determine which of these are bound to albumin (rather than copurified) and whether the bound proteins are intact proteins or peptide fragments. Sequential, independent analyses including both anti‐albumin antibody (anti‐HSA) affinity chromatography and SEC were used to isolate albumin‐bound proteins. RP‐HPLC and 1‐D SDS‐PAGE were then used to further separate the proteins prior to identification by MS/MS. Finally, whole protein molecular weight (MW) MS measurements coupled with protein coverage obtained by MS were combined to assess whether the bound proteins were intact or peptide fragments. Combining the results from multiple approaches, 35 proteins, of which 24 are intact, were found to be associated with albumin, and they include both known high and low abundance proteins.