bluuebunny/crossref_metadata_2025 huggingface dataset:
Progressive decrease in the level of YAPdeltaCs, prosurvival isoforms of YAP, in the spinal cord of transgenic mouse carrying a mutant SOD1 gene
Authors: Morimoto Nobutoshi , Nagai Makiko , Miyazaki Kazunori , Kurata Tomoko , Takehisa Yasushi , Ikeda Yoshio , Kamiya Tatsushi , Okazawa Hitoshi , Abe Koji
Published: October 2008

Amyotrophic lateral sclerosis (ALS) is a progressive and fatal disease caused by the selective death of motor neurons. Between 5% and 10% of ALS patients have a genetically inherited form of the disease known as familial ALS (FALS), and approximately 20% of FALS patients have mutations in the SOD1 gene. Although the mechanism underlying motor neuron death has not yet been fully clarified, it is supposed to be not completely consistent with apoptosis, necrosis, or autophagic cell death. Recently, it was found that general transcriptional repression induces slowly progressive atypical cell death associated with the shift of balance between YAPdeltaCs as prosurvival factors and activated p73 promoting apoptosis. This type of neuronal death was named transcriptional repression–induced atypical death (TRIAD). Therefore, to investigate possible relationships between the mechanism of motor neuron death in ALS and TRIAD, G93ASOD1 transgenic mice (Tg) were examined as an ALS model. The levels of YAPdeltaCs in the spinal cords of Tg mice decreased with disease progression, even during the presymptomatic stage, whereas FL‐YAP, a p73 cofactor that promotes apoptosis, was preserved until the late symptomatic stage. Although the expression of total p73 also decreased with age in Tg mice, the ratio of phosphorylated p73 to total p73 increased during the late symptomatic stage in Tg mice. These results suggest that the progressive decrease in the levels of YAPdeltaCs and the relative increase in phosphorylation of p73 over the time course are correlated with disease progression in ALS model animals. © 2008 Wiley‐Liss, Inc.
Oxygen‐glucose deprivation activates 5‐lipoxygenase mediated by oxidative stress through the p38 mitogen‐activated protein kinase pathway in PC12 cells
Authors: Li Cheng‐Tan , Zhang Wei‐Ping , Lu Yun‐Bi , Fang San‐Hua , Yuan Yu‐Mei , Qi Ling‐Ling , Zhang Li‐Hui , Huang Xiao‐Jia , Zhang Lei , Chen Zhong , Wei Er‐Qing
Published: October 2008

5‐Lipoxygenase (5‐LOX) is a key enzyme catalyzing arachidonic acid to form leukotrienes. We have reported that ischemic‐like injury activates 5‐LOX in PC12 cells; however, the mechanisms are unknown. To determine whether ischemic‐like injury activates 5‐LOX mediated by oxidative stress through the p38 MAPK pathway, we transfected GFP‐5‐LOX into PC12 cells and induced ischemic‐like injury by oxygen‐glucose deprivation (OGD). We found that the transfected GFP‐5‐LOX was localized primarily in the nuclei and translocated to the nuclear envelope after OGD/recovery reaching a maximum 2 hr after a 2‐hr exposure to OGD. The nonselective 5‐LOX inhibitor caffeic acid, 5‐LOX‐activating protein inhibitor MK886, and selective 5‐LOX inhibitor zileuton attenuated the cell injury and reduced the production of 5‐LOX products, cysteinyl leukotrienes, after OGD/recovery. However, only caffeic acid inhibited OGD/recovery‐induced 5‐LOX translocation. OGD/recovery also increased reactive oxygen species (ROS), which was inhibited by caffeic acid only. Hydrogen peroxide, an exogenous ROS, evoked similar cell injury and 5‐LOX translocation, and the inhibitors had effects on the changes after H2O2similar to those after OGD/recovery. Both OGD/recovery and H2O2increased the phosphorylated p38 MAPK level, which was inhibited by caffeic acid and the ROS scavenger edaravone, but not by MK886 or zileuton. Moreover, SB203580 (a p38 MAPK inhibitor) and edaravone inhibited the cell injury and 5‐LOX translocation induced by OGD/recovery and H2O2. Thus, we conclude that OGD/recovery‐induced ischemic‐like injury induces 5‐LOX activation, which is mediated by oxidative stress through activating the p38 MAPK pathway. © 2008 Wiley‐Liss, Inc.
Molecular consequences of altered neuronal cholesterol biosynthesis
Authors: Korade Željka , Kenworthy Anne K. , Mirnics Károly
Published: October 2008

The first dedicated step in de novo cholesterol biosynthesis begins with formation of squalene and ends with the reduction of 7‐dehydrocholesterol by 7‐dehydrocholesterol reductase (Dhcr7) into cholesterol, which is an essential structural and signaling molecule. Mutations in the Dhcr7 gene lead to Smith‐Lemli‐Opitz syndrome (SLOS), which is characterized by developmental deformities, incomplete myelination, and mental retardation. To understand better the molecular consequences of Dhcr7 deficiency in neuronal tissue, we analyzed the effect of cholesterol deficiency on the transcriptome in Neuro2a cells. Transient down‐regulation of Dhcr7 by siRNA led to altered expression of multiple molecules that play critical roles in intracellular signaling or vesicular transport or are inserted into membrane rafts (e.g. Egr1, Snx, and Adam19). A similar down‐regulation was also observed in stable Dhrc7‐shRNA‐transfected cell lines, and the findings were verified by qPCR. Furthermore, we investigated the Dhcr7‐deficient and control cells for the expression of several critical genes involved in lipid biosynthesis. Among these, fatty acid synthase, sterol‐regulatory element binding protein 2, SREBF chaperone, site‐1 protease, and squalene synthase showed a significant down‐regulation, suggesting that, in a neuronal cell line, Dhcr7 is a potent regulator of lipid biosynthesis. Importantly, the gene expression changes were present in both lipid‐containing and cholesterol‐deficient media, suggesting that intrinsic cholesterol biosynthesis is necessary for normal neuronal function and cannot be supplemented from extrinsic sources. © 2008 Wiley‐Liss, Inc.
Activation and reversal of lipotoxicity in PC12 and rat cortical cells following exposure to palmitic acid
Authors: Almaguel Frankis G. , Liu Jo‐Wen , Pacheco Fabio J. , Casiano Carlos A. , De Leon Marino
Published: October 2008

Lipotoxicity involves a series of pathological cellular responses after exposure to elevated levels of fatty acids. This process may be detrimental to normal cellular homeostasis and cell viability. The present study shows that nerve growth factor‐differentiated PC12 cells (NGFDPC12) and rat cortical cells (RCC) exposed to high levels of palmitic acid (PA) exhibit significant lipotoxicity and death linked to an “augmented state of cellular oxidative stress” (ASCOS). The ASCOS response includes generation of reactive oxygen species (ROS), alterations in the mitochondrial transmembrane potential, and increase in the mRNA levels of key cell death/survival regulatory genes. The observed cell death was apoptotic based on nuclear morphology, caspase‐3 activation, and cleavage of lamin B and PARP. Quantitative real‐time PCR measurements showed that cells undergoing lipotoxicity exhibited an increase in the expression of the mRNAs encoding the cell death‐associated proteins BNIP3 and FAS receptor. Cotreatment of NGFDPC12 and RCC cells undergoing lipotoxicity with docosahexaenoic acid (DHA) and bovine serum albumin (BSA) significantly reduced cell death within the first 2 hr following the initial exposure to PA. The data suggest that lipotoxicity in NGFDPC12 and cortical neurons triggers a strong cell death apoptotic response. Results with NGFDPC12 cells suggest a linkage between induction of ASCOS and the apoptotic process and exhibit a temporal window that is sensitive to DHA and BSA interventions. © 2008 Wiley‐Liss, Inc.
Protective function of taurine in glutamate‐induced apoptosis in cultured neurons
Authors: Leon Rebecca , Wu Heng , Jin Ying , Wei Jianning , Buddhala Chandana , Prentice Howard , Wu Jang‐Yen
Published: October 2008

Previously, we showed that taurine protects neurons against glutamate‐induced excitotoxicity by inhibiting the glutamate‐induced increase of [Ca2+]i. In this study, we report that taurine prevents glutamate‐induced chromosomal condensation, indicating that taurine inhibits glutamate‐induced apoptosis. We found that Bcl‐2 was down‐regulated while Bax was up‐regulated by glutamate treatment, and these changes were prevented in the presence of taurine. We have also shown that taurine inhibits glutamate‐induced activation of calpain. Furthermore, calpastatin, a specific calpain inhibitor, also prevented glutamate‐induced cell death. Here we propose the mechanisms underlying glutamate‐induced apoptosis and taurine's inhibition of glutamate‐induced apoptosis to be as follows: glutamate stimulation induces [Ca2+]ielevation, which in turn activates calpain; activation of calpain leads to a reduction of Bcl‐2:Bax ratios; with decreased Bcl‐2:Bax ratios Bax homodimers form, Bax homodimerization, and translocation to the mitochondria result in the release of cytochromec; released cytochromecin turn activates a downstream caspase cascade leading to apoptosis. The antiapoptotic function of taurine is due to its inhibition of glutamate‐induced membrane depolarization. © 2008 Wiley‐Liss, Inc.
Sporadic obstructive hydrocephalus in Aqp4 null mice
Authors: Feng Xuechao , Papadopoulos Marios C. , Liu Jun , Li Lihua , Zhang Di , Zhang Hongguo , Verkman A. S. , Ma Tonghui
Published: October 2008

Aquaporin‐4 (Aqp4) is a water transport protein expressed in glia and ependymocytes in brain. We report here the unexpected occurrence of severe obstructive hydrocephalus in a random subset of Aqp4 knockout mice. Of 612 Aqp4 knockout mice produced by heterozygote–heterozygote or knockout–knockout breedings, 9.6% of offspring manifested progressive encephalomegaly. Encephalomegaly was never seen in wild‐type or Aqp4 heterozygous mice. Examination of the subset encephalomegalic mice revealed marked triventricular hydrocephalus (lateral ventricle size ∼500 mm3), elevated intracranial pressure (19 ± 3 vs. 6.1 ± 0.6 mm Hg), and death by age 6 weeks, with a median survival of 28 days. Intraventricular dye injection studies revealed total obstruction of the cerebral aqueduct. Evans blue extravasation studies indicated an intact blood–brain barrier in the hydrocephalic mice. Brain histology revealed reduced ventricular size and ependymocyte disorganization in some nonhydrocephalic Aqp4 null mice. Our studies establish Aqp4 deletion as a predisposing factor for the development of congenital obstructive hydrocephalus in mice. We suggest that AQP4 polymorphisms might also contribute to the development of aqueduct stenosis in humans. © 2008 Wiley‐Liss, Inc.
Balancing exploration and exploitation in alternative work arrangements: a multiple case study in the professional and management services industry
Authors: Litrico Jean‐Baptiste , Lee Mary Dean
Published: October 2008

In this inductive study we investigate the local context surrounding professionals choosing to work on a reduced‐load basis. We analyze qualitative data collected from key individuals (spouse, boss, co‐worker, and HR manager) composing a network around several professionals working reduced load in the professional and management services industry. We describe the interactions in this network using the concepts of exploration and exploitation in four contexts (organization, workgroup, individual, and family). We also identify three emergent patterns of cross‐level distribution of exploration and exploitation across contexts, labeled Solo Performance, Organic Fluid Adjustment, and Orchestrated Cooperation. Each of these patterns illuminates a specific form of interaction between the dynamics of exploration and exploitation across contexts. We examine the different outcomes of each pattern for the organization, the individual, and the family. Implications of the findings for theories of work‐family interaction, organizational learning, and the organization of work in the professional and management services industry are discussed. Copyright © 2008 John Wiley & Sons, Ltd.
The professionalism of practising law: A comparison across work contexts
Authors: Wallace Jean E. , Kay Fiona M.
Published: October 2008

Traditionally, the literature assumed that solo practitice best exemplifies the ideal professional work arrangement and that when professionals become salaried employees their professionalism is seriously threatened. The primary goal of this paper is to examine lawyers' sense of professionalism across two work contexts: solo practitioner offices and law firm settings. We also examine status distinctions within law firms, between associates and partners, and compare both to independent practitioners. Solo practitioners and law firm partners are similar on most key dimensions of professionalism, whereas the greatest contrasts occur between partners and associates within law firms. Partners and solo practitioners share similar experiences of autonomy and service as owner‐managers, whereas partners and associates share greater collegiality among professionals, perhaps fostered through law firm cultures. All three groups report comparable amounts of variety in their work and are equally committed to the practice of law. The key factors that account for gaps in professionalism reflect the nature of law practices, primarily through time spent with corporate clients and pressure to generate profits. We conclude that different versions of lawyers' professionalism are influenced by the everyday aspects of their work and one version is not necessarily more professional than the other. Copyright © 2008 John Wiley & Sons, Ltd.
Improving Raman spectroscopic differentiation of the geographical origin of rice by simultaneous illumination over a wide sample area
Authors: Kim Yongdan , Lee Sanguk , Chung Hoeil , Choi Hangseok , Cha Kyungjoon
Published: October 2008

This research substantially improved the differentiation of rice of two geographical origins utilizing a wide area illumination (WAI) scheme capable of collecting Raman spectra of a large sample area (28.3 mm2) synchronously without sample rotation. For the purposes of comparison, we also employed a conventional scheme in which the laser illuminated only small areas. Principal component analysis (PCA) was used to differentiate the two geographical origins using the Raman spectra collected through both the conventional and the WAI schemes. The WAI scheme exhibited improved differentiation, primarily due to the fact that the WAI scheme could efficiently produce Raman spectra with a more reliable sample representation, as well as better reproducibility. The spectral feature obtained using the conventional scheme appeared to be more variable; however, this variation resulted more from unsuccessful sample representation than from an actual change in the sample composition. We conclude that the WAI scheme has a good potential for the analysis of diverse agricultural samples that consist of solid granules. Copyright © 2008 John Wiley & Sons, Ltd.
Nitrate modifies urea root uptake and assimilation in wheat seedlings
Authors: Garnica Maria , Houdusse Fabrice , Yvin Jean Claude , Garcia‐Mina Jose Maria
Published: October 2008

BACKGROUND: Some authors suggest that nitrate improves the effects of ammonium and urea nutrition on plant growth via an increase in both the root uptake of ammonium and urea, and the further activation of its assimilation. In order to verify these hypotheses, wheat (Triticum aestivum L.) seedlings were grown with various nitrogen supplies containing the main nitrogen forms (ammonium, nitrate and urea). Root nitrogen uptake and the concentration of each of the nitrogen forms in roots and shoots were studied.

RESULTS: Results indicated that nitrate increases root uptake of ammonium and urea, with this effect being highly significant when the three nitrogen forms are supplied simultaneously. Nitrate significantly increased both urea and ammonium assimilation in the shoot of plants fed urea‐and‐nitrate. However, nitrate did not significantly affect ammonium assimilation in either shoots or roots in plants fed ammonium‐and‐nitrate.

CONCLUSION: The beneficial effect of nitrate seems to be related to an enhancement of root uptake of ammonium and urea, although their assimilation was significantly increased in urea‐fed plants, but not in ammonium‐fed plants. Copyright © 2008 Society of Chemical Industry
Effects of cocoa extract containing polyphenols and methylxanthines on biochemical parameters of obese‐diabetic rats
Authors: Mhd Jalil Abbe Maleyki , Ismail Amin , Chong Pei Pei , Hamid Muhajir , Syed Kamaruddin Syed Hasbullah
Published: October 2008

BACKGROUND: Previous studies have indicated that cocoa extract possesses hypoglycaemic and hypocholesterolaemic properties in streptozotocin‐induced diabetic rats. However, there has been limited research on the effects of cocoa extract on obese‐diabetic (Ob‐db) rats that mimic human diabetes syndrome. Hence this study was initiated to determine the effect of cocoa extract containing polyphenols and methylxanthines on several biochemical parameters, namely glucose level, insulin sensitivity and lipid profiles of Ob‐db rats.

RESULTS: Intake of cocoa extract supplemented with polyphenols (2.17 mg epicatechin, 1.52 mg catechin, 0.25 mg dimer and 0.13 mg trimer g−1 cocoa extract) and methylxanthines (3.55 mg caffeine and 2.22 mg theobromine g−1 cocoa extract) for 4 weeks significantly (P < 0.05) reduced the plasma total cholesterol, triglycerides and low‐density lipoprotein cholesterol of obese‐diabetic rats (Ob‐db + cocoa) compared with non‐supplemented animals (Ob‐db). Short‐term (acute) supplementation of cocoa extract significantly (P < 0.05) reduced the plasma glucose level at 60 and 90 min compared with untreated rats as assessed by the oral glucose tolerance test. However, no significant differences were observed in plasma glucose level, insulin level and insulin sensitivity after chronic (4 weeks) cocoa extract supplementation.

CONCLUSION: The results of this study suggest that cocoa extract possesses hypocholesterolaemic properties and can exert a transient glucose‐lowering effect but not long‐term glucose control. Copyright © 2008 Society of Chemical Industry
Photodynamic therapy of cervical intraepithelial neoplasia with hexaminolevulinate
Authors: Soergel Philipp , Wang Xiuli , Stepp Herbert , Hertel Hermann , Hillemanns Peter
Published: October 2008

Background and Objective

CIN is a disease of women in their reproductive years, and treatment includes excisional techniques with increased risk of preterm deliveries. Photodynamic therapy (PDT) using topical precursor of photoactive porphyrins may be a non‐invasive alternative with minimal side effects. This study assessed the feasibility and response rate of PDT with hexaminolevulinate (HAL) in cervical intraepithelial neoplasia (CIN) and human papillomavirus (HPV) infection.

Study Design/Materials and Methods

Twenty four patients with a CIN 2 or 3 or a persistent CIN 1 and a positive high‐risk HPV‐DNA test were included. Each patient had gynaecologic examination including cervical cytology, HPV DNA testing, colposcopy and biopsy. Ten milliliters of HAL‐thermogel (10 mM) were topically applied to the cervix for 3–5 hours, followed by 1,000 seconds of illumination of both ecto‐ and endocervical canal with red coherent light (wave length 633 nm) using a PDT laser and a special light catheter. Follow‐up examinations were carried out after 3 (cytology, colposcopy, HPV DNA testing, and if needed re‐PDT) and 6 months.

Results

Seven, 10, and 7 patients had a CIN 1, 2, or 3, respectively. Treatment could be accomplished in all cases and no severe side effects were encountered. Fifteen out of the 24 patients had a complete response (15/24 = 63%) and a HPV remission 6 months after 1–3 treatments. The remission rates were 71%, 50%, and 71% for CIN 1, 2 and 3.

Conclusion

HAL PDT seems to be a non‐invasive, repeatable procedure for CIN and cervical HPV infection with minimal side effects which can be easily performed on outpatient basis. Lesers Surg. Med. 40:611–615, 2008. © 2008 Wiley‐Liss, Inc.
Hollow Self‐Doped Polyaniline Micro/Nanostructures: Microspheres, Aligned Pearls, and Nanotubes
Authors: Li Guicun , Zhang Chuanqin , Peng Hongrui , Chen Kezheng , Zhang Zhikun
Published: October 2008

Hollow self‐doped polyaniline (SPAN) micro/nanostructures, such as hollow microspheres, aligned pearls, and nanotubes, have been synthesized by a one‐step chemical oxidation copolymerization of aniline (AN) and m‐aminobenzenesulfonic acid (SAN) using ammonium peroxydisulfate (APS) as the oxidant in aqueous solution. The process is facile and free of any template, surfactant, and external dopants. The shapes and sizes of the hollow SPAN micro/nanostructures can be controlled by adjusting the synthetic parameters, such as the molar ratios of AN and SAN, the concentrations of monomers, and the molar ratios of the monomer and APS. The formation of hollow SPAN micro/nanostructures is possibly related to the self‐assembly of SPAN oligomers at the early stage of the copolymerization reaction. The molecular structures of the SPAN micro/nanostructures were determined by FT‐IR spectroscopy, which reveales that SO groups are bonded to the aromatic rings in SPAN chains.

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Optimal dynamic pricing for sports games with habitual attendance
Authors: Won Dong C. , Lee Young H.
Published: October 2008

This paper provides a theoretical analysis of the optimal pricing decisions of a sports team that maximizes lifetime profits in sports markets where game attendance is habit‐forming for sports fans. The long‐run equilibrium price and attendance level are found to be greater than the counterparts of the static framework, respectively. The infinite horizon model shows that the pricing strategy of the firm brings about an upward‐crossing of two different dynamic price paths where the price path with stronger habit formation initially stays below, catches up, and ultimately rises above the price path with weaker habit formation. It is worth noting that the upward‐crossing phenomenon is not fully understood in a finite‐period model. Copyright © 2008 John Wiley & Sons, Ltd.
Dystonia Associated with pontomesencephalic lesions
Authors: Loher Thomas J. , Krauss Joachim K.
Published: October 2008

Secondary dystonia is well known subsequent to lesions of the basal ganglia or the thalamus. There is evidence that brainstem lesions may also be associated with dystonia, but little is known about pathoanatomical correlations. Here, we report on a series of four patients with acquired dystonia following brainstem lesions. There were no basal ganglia or thalamic lesions. Three patients suffered tegmental pontomesencephalic hemorrhage and one patient diffuse axonal injury secondary to severe craniocerebral trauma. Dystonia developed with a delay of 1 to 14 months, at a mean delay of 6 months. The patients' mean age at onset was 33 years (range 4–56 years). All patients presented with hemidystonia combined with cervical dystonia, and two patients had craniofacial dystonia in addition. Three patients had postural or kinetic tremors. Dystonia was persistent in three patients, and improved gradually in one. There was little response to medical treatment. One patient with hemidystonia combined with cervical dystonia improved after thalamotomy. Overall, the phenomenology of secondary dystonia due to pontomesencephalic lesions is similar to that caused by basal ganglia or thalamic lesions. Structures involved include the pontomesencephalic tegmentum and the superior cerebellar peduncles. Such lesions are often associated with fatal outcome. While delayed occurrence of severe brainstem dystonia appears to be rare, it is possible that mild manifestations of dystonia might be ignored or not be emphasized in the presence of other disabling deficits. © 2008 Movement Disorder Society
Expression of Lewy body protein septin 4 in postmortem brain of Parkinson's disease and control subjects
Authors: Shehadeh Lina , Mitsi Georgia , Adi Nikhil , Bishopric Nanette , Papapetropoulos Spyridon
Published: October 2008

In Parkinson's disease (PD) neuronal degeneration is associated with abnormal protein aggregation in various forms including Lewy bodies (LBs). A major component of LBs is α‐synuclein; septin 4 (SEPT4), a polymerizing GTP‐binding protein that serves as scaffold for diverse molecules has been found to colocalize with α‐synuclein in LBs. The central role of SEPT4 in the etiopathogenesis of PD has been suggested since SEPT4 also shows a physiological association with α‐synuclein and serves as a substrate for parkin. To this end, we studied the expression of septin 4 and α‐synuclein in postmortem human substantia nigra (SN) and amygdala from patients with PD and healthy controls. Twenty patients (14 men : 6 women, onset 63.0 ± 11.4 years, age 77.3 ± 7.6 years, Hoehn and Yahr 4.05/5) and 9 neurologically healthy controls (4 men/5 women, age at death 80.1 ± 8.6 years) were studied. Sporadic PD cases showed a statistically significant decrease of the fold change (FC) of SNCA (FC = 0.31, P = 0.00001) and SEPT4 (FC = 0.67, P = 0.054) gene expressions in the SN and the amygdala (SNCA: FC = 0.49, P = 0.02; SEPT4: FC = 0.32, P = 0.007) versus healthy controls. However, an increase of both proteins in PD versus control subjects was observed with immunoblotting. The semi‐quantitative protein ratio calculations revealed more than 10‐fold increases for both SEPT4 and α‐synuclein in PD versus control subjects. We present for the first time similar signal expression patterns and parallel accumulation of SEPT4 and α‐synuclein in well‐characterized postmortem PD brain. Considering the heterogeneous etiology of sporadic PD and the variability of individual human samples, SEPT4 accumulation may be regarded as one of the common pathological changes in PD and should therefore be further explored. © 2008 Movement Disorder Society
Respective potencies of Botox® and Dysport® in a human skin model: A randomized, double‐blind study
Authors: Kranz Gottfried , Haubenberger Dietrich , Voller Bernhard , Posch Martin , Schnider Peter , Auff Eduard , Sycha Thomas
Published: October 2008

Mouse units used to quantify the activity of botulinum A toxin preparations are not equivalent and issues concerning efficacy and safety remain with regard to their respective potencies and diffusion qualities in human tissue. We compared the effects of Botox® (BOT) and Dysport® (DYS) in different doses and dilutions in a human skin model. Eighteen (8 women, 10 men) healthy volunteers, aged 28.4 years ± 5.7 years were injected intradermally with pure saline, BOT and DYS at 16 points in the abdomen in random order and in a double‐blind condition, using two conversion ratios (1:3 and 1:4) and three different dilution schemes. For an objective outcome, the Ninhydrin sweat test was used to compare the anhidrotic areas. Both preparations showed a linear dose and dilution relationship with similar variances of responses for anhidrosis and hypohidrosis, indicating the same reliability of response. The dose equivalence conversion ratios (BOT: DYS) were 1:1.3 for anhidrosis and 1:1.6 for hypohidrosis (1:1.1‐1.5 and 1:1.4‐1.8 95% confidence intervals). The diffusion characteristics of both products were similar. A dose equivalence factor of more than 1:2 (BOT:DYS) is not supported by these objective and reproducible data. © 2008 Movement Disorder Society
Stiff‐three limbs syndrome
Authors: Teive Hélio A.G. , Munhoz Renato P. , Cardoso Juliana , Amaral Vanice C.G. , Werneck Lineu C.
Published: October 2008

We report a patient diagnosed with stiff‐three limbs syndrome, without continuous motor unit activity in the electrophysiologic exam, with successful treatment with intravenous immunoglobulin. © 2008 Movement Disorder Society
Characterization of phospholipases C β and γ and their possible roles inChaetopterusegg activation
Authors: Yin Xunqin , Eckberg William R.
Published: October 2008

Intracellular calcium release from the endoplasmic reticulum is a hallmark at egg activation of both vertebrates and invertebrates. This fertilization‐associated calcium release results from generation of the second messenger inositol 1,4,5‐trisphosphate (IP3) by one or more phospholipases C (PLC). We characterizedChaetopterusPLCβ and γ by reverse transcription/degenerate oligonucleotide primed PCR and rapid amplification of cDNA end PCR. Phylogenetic analyses suggested that the deduced PLCβ protein shared the greatest homology with mammalian PLCβ4; the deduced PLCγ protein shared the greatest homology with starfish PLCγ and diverged from mammalian PLCγ before mammalian the PLCγ1 and γ2 isoforms diverged. Western blot analyses with specific anti‐PLCβ and γ antibodies, respectively, revealed that 135 and 150 kDa proteins were expressed in eggs. The general PLC antagonist U‐73122 blocked fertilization‐induced egg activation; however, the inactive analog, U‐73343, had no effect on egg activation. We further tested whether egg activation was G protein‐PLCβ and/or protein tyrosine kinase‐PLCγ dependent. Cholera and pertussis toxins, well‐known effectors of G proteins, had no effect on egg activation; while two antagonists of PTK, genistein and tyrphostin B42, inhibited both fertilization‐induced and artificial egg activation. Taken together, our studies suggested that PLC activity from eggs contributes toChaetopterusegg activation and PLCγ might play an important role during this biological process. Mol. Reprod. Dev. 76: 460–470, 2009. © 2008 Wiley‐Liss, Inc.
Purification and multimer formation of allurin, a sperm chemoattractant from Xenopus laevis egg jelly
Authors: Sugiyama Hitoshi , Burnett Lindsey , Xiang Xueyu , Olson John , Willis Shaun , Miao Amy , Akema Tatsuo , Bieber Allan L. , Chandler Douglas E.
Published: October 2008

Allurin, a sperm chemoattractant isolated from Xenopus laevis egg jelly, can be purified in one step from an extract of diffusible jelly proteins (“egg water”) using a FPLC or HPLC anion exchange column and a multi‐step NaCl gradient. Allurin homomultimers were detected by Western blotting with antibodies prepared against the purified protein or peptides within the protein. Allurin multimers were stable and resisted dissociation by SDS and β‐mercaptoethanol. Alkylation of allurin provided evidence for two free sulfhydryl groups but did not eliminate multimer formation, suggesting that intermolecular disulfide bond formation is not required for allurin aggregation. Concentration of egg water was accompanied by a reduction of chemoattractant activity that could not be fully accounted for by homomultimer formation. Rather, the presence of a multiphasic dose‐activity curve upon partial purification and formation of hetero‐allurin complexes during concentration suggested that egg water may contain allurin‐binding proteins that reduce multimer formation and activity. Mol. Reprod. Dev. 76: 527–536, 2009. © 2008 Wiley‐Liss, Inc.
Gene expression and development of early pig embryos produced by serial nuclear transfer
Authors: Xing Xiaojun , Magnani Luca , Lee Kiho , Wang Chunmin , Cabot Ryan A. , Machaty Zoltan
Published: October 2008

During nuclear transfer, reprogramming makes the donor nucleus capable of directing development of the reconstructed embryo. In most cases reprogramming is incomplete, which leads to abnormal expression of early embryonic genes and subsequently, to reduced developmental potential. In the present study, we monitored the expression of Oct4, Nanog, and Sox2 in cloned porcine embryos and evaluated whether serial nuclear transfer, the transfer of nuclei of cloned embryos into enucleated oocytes, has the potential to provide a more complete reprogramming of the donor genome. The data suggested that Nanog and Sox2 expression is properly reactivated after nuclear transfer, but the relative abundance of Oct4 transcripts is abnormally low in cloned porcine blastocysts compared to control embryos produced by in vitro fertilization. When the nuclei of 8‐ to 16‐cell stage cloned embryos were introduced into enucleated oocytes to expose the chromosomes repeatedly to the ooplasmic factors, the resulting embryos showed poor developmental potential: a significantly lower percentage of embryos developed to the 4‐cell (12.0% vs. 31.8%), 8‐cell (3.1% vs. 15.0%) and blastocyst (0% vs. 8.7%) stages compared to those produced following a single round of nuclear transfer (P < 0.05). The additional time for reprogramming also did not improve gene expression. By the late 4‐cell stage, Oct4 and Sox2 expression levels were low in serial nuclear transfer embryos compared to those in embryos generated by in vitro fertilization or nuclear transfer. Overall, both developmental and gene expression data indicated that reprogramming of the donor nucleus could not be improved by serial nuclear transfer in the pig. Mol. Reprod. Dev. 76: 555–563, 2009. © 2008 Wiley‐Liss, Inc.
Heat shock of porcine zygotes immediately after oocyte activation increases viability
Authors: Isom S. Clay , Lai Liangxue , Prather Randall S. , Rucker Edmund B.
Published: October 2008

We evaluated the effect of different timing variations of an applied heat shock on parthenogenetically activated (PA) porcine embryos. PA embryos were heat shocked for 9 hr at 42°C from either 0–9 hr post activation (hpa; 09HS), 13–22 hpa (1322HS), or 22–31 hpa (2231HS). Analysis of 24‐hr cleavage rates (P < 0.0001), day 5 cell numbers (P < 0.005), day 7 blastocyst rates (P < 0.0001), and day 7 cell numbers (P < 0.05) showed that 09HS embryos developed more successfully in vitro than did all other treated and control embryos. In vitro fertilized (IVF) embryos were exposed to similar heat treatments as described for PA embryos, and embryos derived from somatic cell nuclear transfer (SCNT) were exposed only to the control and 09HS treatments to assess the effects of the different heat treatments on the timing of first cleavage and development to blastocyst. Embryos derived from both IVF and SCNT showed higher proportions of cleaved embryos on day 1 of development when heat shocked immediately after fertilization or fusion/activation as compared to NHS controls (P < 0.05). Blastocyst rates however, showed only modest (IVF; P = 0.089) or no (SCNT; P > 0.1) improvement as compared with control embryos. In summary, exposing PA embryos to elevated temperatures immediately after oocyte activation results in dramatically enhanced developmental potential. A thorough characterization of this phenomenon may yield findings that can serve to increase the efficiency with which PA, IVF, and SCNT embryos are produced in vitro. Mol. Reprod. Dev. 76: 548–554, 2009. © 2008 Wiley‐Liss, Inc.
Modeling three‐dimensional crack propagation—A comparison of crack path tracking strategies
Authors: Jäger P. , Steinmann P. , Kuhl E.
Published: October 2008

The development of a new finite element technique for the simulation of discontinuous failure phenomena in three dimensions is the key objective of this study. In contrast to the widely used extended finite element technique, we apply a purely deformation‐based strategy based on an independent interpolation of the deformation field on both sides of the discontinuity. This method has been applied successfully for two‐dimensional crack propagation problems in the past. However, when it comes to three‐dimensional failure phenomena, it faces the same difficulties as the extended finite element method. Unlike in two dimensions, the characterization for the three‐dimensional failure surface is non‐unique and the tracking of the discrete crack can be performed in several conceptually different ways. In this work, we review the four most common three‐dimensional crack tracking strategies. We perform a systematic comparison in terms of standard algorithmic quality measures such as mesh independency, efficiency, robustness, stability and computational cost. Moreover, we discuss more specific issues such as crack path continuity and integratability in commercial finite element packages. The features of the suggested crack tracking algorithms will be elaborated by means of characteristic benchmark problems in failure analysis. Copyright © 2008 John Wiley & Sons, Ltd.
Singularity enrichment for complete sliding contact using the partition of unity finite element method
Authors: Giner E. , Sukumar N. , Fuenmayor F. J. , Vercher A.
Published: October 2008

In this paper, the numerical modelling of complete sliding contact and its associated singularity is carried out using the partition of unity finite element method. Sliding interfaces in engineering components lead to crack nucleation and growth in the vicinity of the contact zone. To accurately capture the singular stress field at the contact corner, we use the partition of unity framework to enrich the standard displacement‐based finite element approximation by additional (enriched) functions. These enriched functions are derived from the analytical expression of the asymptotic displacement field in the vicinity of the contact corner. To characterize the intensity of the singularity, a domain integral formulation is adopted to compute the generalized stress intensity factor (GSIF). Numerical results on benchmark problems are presented to demonstrate the improved accuracy and benefits of this technique. We conduct an investigation on issues pertaining to the extent of enrichment, accurate numerical integration of weak‐form integrals and the rate of convergence in energy. The use of partition of unity enrichment leads to accurate estimations of the GSIFs on relatively coarse meshes, which is particularly beneficial for modelling non‐linear sliding contacts. Copyright © 2008 John Wiley & Sons, Ltd.
A 3D BEM model for liquid sloshing in baffled tanks
Authors: Firouz‐Abadi R. D. , Haddadpour H. , Noorian M. A. , Ghasemi M.
Published: October 2008

The present work aims at developing a boundary element method to determine the natural frequencies and mode shapes of liquid sloshing in 3D baffled tanks with arbitrary geometries. Green's theorem is used with the governing equation of potential flow and the walls and free surface boundary conditions are applied. A zoning method is introduced to model arbitrary arrangements of baffles. By discretizing the flow boundaries to quadrilateral elements, the boundary integral equation is formulated into a general matrix eigenvalue problem. The governing equations are then reduced to a more efficient form that is merely represented in terms of the potential values of the free surface nodes, which reduces the size of the computational matrices considerably. The results obtained using the proposed model are verified in comparison with the literature and very good agreement is achieved. Finally, a number of example tanks having common configurations are used to investigate the effect of baffle on sloshing frequencies and some conclusions are outlined. Copyright © 2008 John Wiley & Sons, Ltd.
Robust and direct evaluation of J2 in linear elastic fracture mechanics with the X‐FEM
Authors: Legrain G. , Moës N. , Verron E.
Published: October 2008

The aim of the present paper is to study the accuracy and the robustness of the evaluation of Jk‐integrals in linear elastic fracture mechanics using the extended finite element method (X‐FEM) approach. X‐FEM is a numerical method based on the partition of unity framework that allows the representation of discontinuity surfaces such as cracks, material inclusions or holes without meshing them explicitly. The main focus in this contribution is to compare various approaches for the numerical evaluation of the J2‐integral. These approaches have been proposed in the context of both classical and enriched finite elements. However, their convergence and the robustness have not yet been studied, which are the goals of this contribution. It is shown that the approaches that were used previously within the enriched finite element context do not converge numerically and that this convergence can be recovered with an improved strategy that is proposed in this paper. Copyright © 2008 John Wiley & Sons, Ltd.
Space–time approach to numerical analysis of a string with a moving mass
Authors: Bajer Czesław I. , Dyniewicz Bartłomiej
Published: October 2008

Inertial loading of strings, beams and plates by mass travelling with near‐critical velocity has been a long debate. Typically, a moving mass is replaced by an equivalent force or an oscillator (with ‘rigid’ spring) that is in permanent contact with the structure. Such an approach leads to iterative solutions or imposition of artificial constraints. In both cases, rigid constraints result in serious computational problems. A direct mass matrix modification method frequently implemented in the finite element approach gave reasonable results only in the range of relatively low velocities. In this paper we present the space–time approach to the problem. The interaction of the moving mass/supporting structure is described in a local coordinate system of the space–time finite element domain. The resulting characteristic matrices include inertia, Coriolis and centrifugal forces. A simple modification of matrices in the discrete equations of motion allows us to gain accurate analysis of a wide range of velocities, up to the velocity of the wave speed. Numerical examples prove the simplicity and efficiency of the method. The presented approach can be easily implemented in the classic finite element algorithms. Copyright © 2008 John Wiley & Sons, Ltd.
A contact algorithm for frictional crack propagation with the extended finite element method
Authors: Liu Fushen , Borja Ronaldo I.
Published: October 2008

We present an incremental quasi‐static contact algorithm for path‐dependent frictional crack propagation in the framework of the extended finite element (FE) method. The discrete formulation allows for the modeling of frictional contact independent of the FE mesh. Standard Coulomb plasticity model is introduced to model the frictional contact on the surface of discontinuity. The contact constraint is borrowed from non‐linear contact mechanics and embedded within a localized element by penalty method. Newton–Raphson iteration with consistent linearization is used to advance the solution. We show the superior convergence performance of the proposed iterative method compared with a previously published algorithm called ‘LATIN’ for frictional crack propagation. Numerical examples include simulation of crack initiation and propagation in 2D plane strain with and without bulk plasticity. In the presence of bulk plasticity, the problem is also solved using an augmented Lagrangian procedure to demonstrate the efficacy and adequacy of the standard penalty solution. Copyright © 2008 John Wiley & Sons, Ltd.
Numerically consistent regularization of force‐based frame elements
Authors: Scott M. H. , Hamutçuoğlu O. M.
Published: October 2008

Recent advances in the literature regularize the strain‐softening response of force‐based frame elements by either modifying the constitutive parameters or scaling selected integration weights. Although the former case maintains numerical accuracy for strain‐hardening behavior, the regularization requires a tight coupling of the element constitutive properties and the numerical integration method. In the latter case, objectivity is maintained for strain‐softening problems; however, there is a lack of convergence for strain‐hardening response. To resolve the dichotomy between strain‐hardening and strain‐softening solutions, a numerically consistent regularization technique is developed for force‐based frame elements using interpolatory quadrature with two integration points of prescribed characteristic lengths at the element ends. Owing to manipulation of the integration weights at the element ends, the solution of a Vandermonde system of equations ensures numerical accuracy in the linear‐elastic range of response. Comparison of closed‐form solutions and published experimental results of reinforced concrete columns demonstrates the effect of the regularization approach on simulating the response of structural members. Copyright © 2008 John Wiley & Sons, Ltd.
Comparison of FDG‐PET scans to conventional radiography and bone scans in management of Langerhans cell histiocytosis
Authors: Phillips Michelle , Allen Carl , Gerson Paul , McClain Kenneth
Published: October 2008

Background

We evaluated the effectiveness of FDG‐PET scans in identifying sites of active disease and assessing response to therapy in patients with Langerhans cell histiocytosis (LCH). Changes in standardized uptake value (SUV) indicated increased or decreased disease activity before changes are evident by plain films or bone scans.

Methods

One hundred and two PET scans for 44 patients (41 children, 3 adults) with biopsy‐proven LCH were compared with 83 corollary imaging modalities and were rated for overall clinical utility: false positive or negative (“inferior”), confirming lesions identified by another imaging modality (“confirmatory”), or showing additional lesions, response to therapy or recurrence of disease activity (“superior”), in comparison to bone scans, MRI, CT or plain films.

Results

FDG‐PET was rated superior in that 90/256 (35%) new, recurrent, or lesions responding to therapy were identified via change in standard uptake value (SUV) before other radiographic changes. PET scans confirmed active LCH in 146/256 (57%). FDG‐PET was superior to bone scans in that 8/23 (34%) lesions, 11/53 (21%) comparisons to lesions found by MRI, 13/64 (20%) CT, and 58/116 (50%) plain films. PET scans confirmed lesions found by: 14/23 (61%) bone scans, 33/53 (62%) MRI, 45/64 (65%) CT, and 54/116 (46%) of plain films.

Conclusions

Whole body FDG‐PET scans can detect LCH activity and early response to therapy with greater accuracy than other imaging modalities in patients with LCH lesions in the bones and soft tissues. Whole‐body FDG‐PET scanning is an important and informative study at diagnosis and for following disease course in patients with LCH. Pediatr Blood Cancer 2009;52:97–101. © 2008 Wiley‐Liss, Inc.
Process optimization of devulcanization of waste rubber powder from syringe stoppers by twin screw extruder using response surface methodology
Authors: Maridass B. , Gupta B.R.
Published: October 2008

Response surface methodology was used to predict the optimal processing parameters viz. barrel temperature and screw speed in a counter‐rotating twin screw extruder for devulcanization of rubber powder obtained from factory waste of medical syringe stoppers. Central composite rotatable design for two variables at five levels was chosen as the experimental design. The results obtained after measuring the responses were fitted as two‐variable second‐order equations. The corresponding contour plot, response surface plot, Pareto chart, and main effect plot were plotted and analyzed. Optimum properties were predicted at temperature 180°C and screw speed 27 rpm, which was confirmed experimentally. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
Clay intercalation and influence on flammability and crystallization behaviors of POE‐based nanocomposites
Authors: Lu Hongdian , Hu Yuan , Li Ming , Song Lei
Published: October 2008

Ethylene‐octene copolymer (POE)‐based nanocomposites were prepared from POE or maleic anhydride grafted POE with organo‐modified montmorillonite (OMT) using melt blending technique. Their morphology, flammability, and crystallization behavior were investigated by X‐ray diffraction (XRD), transmission electron microscopy (TEM), cone calorimeter, and differential scanning calorimetry (DSC). XRD and TEM studies confirmed the intercalation of clay layers within the POE matrix whereas the exfoliation throughout the maleated POE matrix. Cone calorimetry results exhibited that the reduction in heat release rate of exfoliated maleated‐POE/OMT nanocomposite was greater than that of intercalated POE/OMT nanocomposite. The DSC results suggested that the nonisothermal kinetics crystallization of the exfoliated nanocomposite corresponded to tridimensional growth with heterogeneous nucleation. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers