bluuebunny/crossref_metadata_2025_split huggingface dataset:
A streamlined molecular biology module for undergraduate biochemistry labs
Authors: Muth Gregory W. , Chihade Joseph W. 
Published: May 2008

AbstractSite‐directed mutagenesis and other molecular biology techniques, including plasmid manipulation and restriction analysis, are commonly used tools in the biochemistry research laboratory. In redesigning our biochemistry lab curricula, we sought to integrate these techniques into a term‐long, project‐based course. In the module presented here, students use structural data to design a site‐directed mutant and make the mutation using the Künkel method. A second, silent mutant, that creates or removes a restriction site, is simultaneously introduced. Restriction digestion and agarose gel electrophoresis are used to assess the success of mutagenesis. Placing these procedures in the context of continuous, student‐driven project serves to create a “research style” laboratory environment.
Psycho‐social determinants of quality of life in children and adolescents with haemophilia—a cross‐cultural approach
Authors: Bullinger Monika , von Mackensen Sylvia 
Published: May 2008

AbstractQuality of life (QoL) of children with chronic conditions has received increasing attention in recent years. While frequent paediatric health conditions and life‐threatening conditions are in the foreground, QoL of children with rare diseases such as haemophilia is scarce. While haemophilia‐specific instruments to assess QoL in children have been developed, cross‐cultural comparison of QoL and its determinants has not been addressed so far. QoL and potential psychosocial determinants such as coping were assessed in 298 paediatric haemophilia patients from six European countries demonstrating significant differences in QoL between countries. Results indicated that psychosocial predictors varied across countries, although life satisfaction and social support explained the highest proportion of variance and, moreover, superseded clinical characteristics. These findings suggest that intervention programmes should be geared towards enhancing psychosocial resources in children and adolescents with haemophilia. Copyright © 2008 John Wiley & Sons, Ltd.
Demographic and psychosocial correlates of quality of life in the elderly from a cross‐cultural perspective
Authors: Dragomirecká Eva , Bartoňová Jitka , Eisemann Martin , Kalfoss Mary , Kilian Reinhold , Martiny Klaus , von Steinbüchel Nicole , Schmidt Silke 
Published: May 2008

AbstractWe compared the quality of life (QOL) of older adults in a post‐communist country (the Czech Republic) with those living in traditional western democracies. The sample comprised 1981 respondents aged 60+ (from 60 to 99). The subjective QOL was measured using the WHOQOL‐BREF and the add‐on module for older adults, the WHOQOL‐OLD. The findings showed higher score of depressive symptoms measured by the GDS scale and lower QOL in Czech sample as compared to other centres. Analyses of factors related to QOL of older adults showed similar patterns for the Czech sample and other centres with depression emerging as the strongest determinant of reduced QOL Findings also underline that subjective quality of life measurement reflects cross‐country differences in accordance with objective indicators of national prosperity. Copyright © 2008 John Wiley & Sons, Ltd.
Short forms of subjective quality of life assessments from cross‐cultural studies for use in surveys with different populations
Authors: Mühlan Holger , Bullinger Monika , Power Mick , Schmidt Silke 
Published: May 2008

AbstractAmong several advances in quality of life (QOL) assessment development, such as cross‐cultural comparability of measurements, inclusion of more specific target populations, and assessment on different levels of QOL generality, economy of measurement has become of increasing importance. As a consequence, construction of short forms and indices of original measures is common in QOL assessment development. The present paper puts special emphasis upon the issue of shortening measures and developing short forms in QOL assessment in relation to this development. Some basic principles and procedures of short‐form development in general are outlined, and selected prominent examples of short‐form development as applied to QOL assessment are described. Copyright © 2008 John Wiley & Sons, Ltd.
An experimental test of whether bar instability contributes to the formation, periodicity and maintenance of pool–riffle sequences
Authors: Wilkinson Scott N. , Rutherfurd Ian D. , Keller Robert J. 
Published: May 2008

AbstractPool–riffle sequences (PRSs) are periodic river‐bed morphologies with wavelengths several times the channel width. Causes of PRS formation and maintenance are not clearly understood, which may limit the effectiveness of protection and rehabilitation measures. Some confusion has existed about whether the PRS morphology is the same as or distinct from alternate bars. In this paper we investigate whether the bar instability forming alternate bars also contributes to PRS formation, periodicity and maintenance. This was unclear because bar instability occurs only when the ratio of channel width/depth exceeds a critical value, generally understood to be approximately 10, which is larger than the width‐to‐depth ratio of many PRSs. A mobile‐bed physical model is used to test whether bar instability occurs in channels characteristic of PRS morphology, with low width‐to‐depth ratio, and high relative roughness. The physical model was scaled from a prototype PRS in a gravel and cobble bed river. Alternate bars formed in the model at channel width‐to‐depth ratios as low as 3·8. The wavelength of the alternate bars formed was generally 2·2–5 times channel width, which was similar to the prototype PRS. Therefore, bar instability can occur in virtually all PRSs, and it contributes to the widespread formation of periodic PRS morphology. The model showed that maintenance of the bar height in the prototype PRS also depends on variations in channel width. It is concluded that periodic PRSs are formed and maintained by the interaction between bar instability, and flow deflections associated with variations in channel geometry such as width variation. Resonance between bar instability and three‐dimensional bed forms such as alternate bars and variations in channel geometry. Variations in channel geometry are also important in determining the location and dimensions of individual pools and bars. Copyright © 2008 John Wiley & Sons, Ltd.
Oncolytic virotherapy as a personalized cancer vaccine
Authors: Li Qi‐Xiang , Liu Guohong , Wong‐Staal Flossie 
Published: May 2008

AbstractOncolytic virotherapy has demonstrated multimodal antitumor mechanisms in both preclinical and clinical settings for cancer treatment, including antitumor immunity. Compared with conventional immunotherapy, oncolytic viruses have the advantages of simultaneous cytoreduction and conferring personalized anticancer immunity, but without the need of personalized manufacture. Additionally, oncolytic viruses can be further engineered to delete immunosuppressive viral components and to insert transgenes that enhance antitumor immunity. Finally, combination with new immunomodulating agents (e.g., cyclophosphamide) or cell therapy approaches will likely further augment specific antitumor immunity of virotherapy. Virotherapy could become a new paradigm for potent, safe and practical therapeutic vaccines for cancer. © 2008 Wiley‐Liss, Inc.
Adeno‐associated virus‐mediated gene transfer
Authors: Srivastava Arun 
Published: May 2008

AbstractAlthough the remarkable versatility and efficacy of recombinant adeno‐associated virus 2 (AAV2) vectors in transducing a wide variety of cells and tissues in vitro, and in numerous pre‐clinical animal models of human diseases in vivo, have been well established, the published literature is replete with controversies with regard to the efficacy of AAV2 vectors in hematopoietic stem cell (HSC) transduction. A number of factors have contributed to these controversies, the molecular bases of which have begun to come to light in recent years. With the availability of several novel serotypes (AAV1 through AAV12), rational design of AAV capsid mutants, and strategies (self‐complementary vector genomes, hematopoietic cell‐specific promoters), it is indeed becoming feasible to achieve efficient transduction of HSC by AAV vectors. Using a murine serial bone marrow transplantation model in vivo, we have recently documented stable integration of the proviral AAV genome into mouse chromosomes, which does not lead to any overt hematological abnormalities. Thus, a better understanding of the AAV–HSC interactions, and the availability of a vast repertoire of novel serotype and capsid mutant vectors, are likely to have significant implications in the use of AAV vectors in high‐efficiency transduction of HSCs as well as in gene therapy applications involving the hematopoietic system. J. Cell. Biochem. 105: 17–24, 2008. © 2008 Wiley‐Liss, Inc.
The effect of rottlerin in calcium regulation in HMC‐1560 cells is mediated by a PKC‐δ independent effect
Authors: Alonso Eva , Alfonso Amparo , Löber Kristin , Botana Luis M. 
Published: May 2008

AbstractThe human mast cell line (HMC‐1560) is a good model for Ca2+ signaling studies, because intracellular alkalinization is the mainly histamine release stimulus without changes in the intracellular Ca2+ levels. This fact allows us to study Ca2+ changes without degranulation, since this process can affected cellular viability. Ionomycin and thapsigargin have been fully used for induced Ca2+ influx across SOC channels. When HMC‐1560 cells are incubated with rottlerin, 5 µM, for 5 min a strong inhibition of ionomycin‐induced Ca2+ influx is observed. However, when thapsigargin stimulates Ca2+ influx, rottlerin did not show any effect on Ca2+ levels. This fact point two possibilities, ionomycin and thapsigargin might activate different SOC channels or that these drugs might activate the same channel but in a different way in HMC‐1560 cells. The rottlerin inhibition of ionomycin‐induced Ca2+ influx is PKC‐δ independent and this effect is not related with the store depletion, since rottlerin has the same effect when it is added before or after the stores are empty. FCCP, a know uncoupler of oxidative phosphorylation in mitochondria, induces the same inhibition in ionomycin Ca2+ influx than rottlerin which point to the mitochondria as a cellular target to rottlerin. J. Cell. Biochem. 105: 255–261, 2008. © 2008 Wiley‐Liss, Inc.
Every longest circuit of a 3‐connected, K3,3‐minor free graph has a chord
Authors: Birmelé Etienne 
Published: May 2008

AbstractCarsten Thomassen conjectured that every longest circuit in a 3‐connected graph has a chord. We prove the conjecture for graphs having no K3,3 minor, and consequently for planar graphs. © 2008 Wiley Periodicals, Inc. J Graph Theory 58: 293–298, 2008
Antisense suppression of tau in cultured rat oligodendrocytes inhibits process formation
Authors: Gordon David , Kidd Grahame J. , Smith Ross 
Published: May 2008

AbstractThe microtubule‐associated protein tau is integral to neuronal process development and has a role in the pathogenesis of several neurodegenerative conditions. We examined possible roles for tau in cultured oligodendrocyte process formation by using antisense oligonucleotide treatment. Inhibition of tau synthesis with single oligonucleotides resulted in decreased tau protein levels and significantly shorter cellular processes. Simultaneous use of two nonoverlapping oligonucleotides caused a major reduction in tau levels and severely inhibited process outgrowth. The timing of oligonucleotide addition to oligodendrocyte cultures was important, with addition of antisense at the time of plating into culture having the most significant effect on morphology through reduction of tau expression. © 2008 Wiley‐Liss, Inc.
Two motifs within the tau microtubule‐binding domain mediate its association with the hsc70 molecular chaperone
Authors: Sarkar Mitul , Kuret Jeff , Lee Gloria 
Published: May 2008

AbstractTau, a microtubule‐associated protein with multiple phosphorylation sites, forms aggregates that correlate with neurodegeneration in Alzheimer's disease and several other neurodegenerative diseases, termed tauopathies. Hsc70 is a highly expressed constitutive chaperone that can drive conformational change in proteins, prevent the aggregation of its substrates, recognize misfolded substrates, and facilitate their degradation. Here, we show that hsc70 binds to the microtubule‐binding domain of tau in vitro and in vivo, without an absolute requirement for tau phosphorylation. Binding requires a carboxy‐terminal region of hsc70 comprising its peptide‐binding and variable domains. We have identified two hsc70 binding sites on tau and hydrophobic amino acids crucial for hsc70 binding. Interestingly, these hsc70 binding sites correspond to the β‐structure elements that have been previously reported to facilitate tau aggregation. Thus, it is possible that hsc70 binding might directly inhibit tau–tau interactions that precede tau oligomerization and aggregation. Our results provide an important stimulus for research into how the hsc70–tau interaction might affect tau fate in normal cells and in disease. © 2008 Wiley‐Liss, Inc.
Hypoxia‐induced deactivation of NGF‐mediated ERK1/2 signaling in hippocampal cells: Neuroprotection by acetyl‐L‐carnitine
Authors: Barhwal Kalpana , Hota Sunil Kumar , Prasad Dipti , Singh Shashi Bala , Ilavazhagan G. 
Published: May 2008

AbstractCellular and molecular pathways underlying hypoxic neurotoxicity and cell death are multifaceted and complex. Although many potentially neuroprotective agents have been investigated, the protection conferred is often inadequate, resulting in their insufficient clinical utility. In light of the above, we investigated the therapeutic potential and mechanism of action of acetyl‐L‐carnitine (ALCAR) in protecting hippocampal neurons from hypoxia‐induced neurotoxicity and cellular death. Results showed decreased viability of hippocampal cells when exposed to hypoxia (3% O2) for 48 hr along with concomitant membrane depolarization, adenosine triphosphate depletion, DNA fragmentation, accentuated free radical production, and lactate dehydrogenase activity. Pretreatment with ALCAR significantly attenuated hypoxia‐induced cytotoxicity in a dose‐dependent manner and improved cellular glutathione levels and cytochrome c oxidase activity compared with normoxic controls. Supplementation of ALCAR also prevented apoptosis by down‐regulating caspase‐3 levels, cytochrome c release, and p‐Bcl‐2 expression. A decrease in nerve growth factor (NGF) was observed in hypoxic stress despite increased phosphorylation of ERK1/2 (extracellular signal–related kinase) and its downstream effector, Elk‐1. Supplementation of ALCAR, on the other hand, up‐regulated NGF and tyrosine kinase A expression along with concomitant increase in ERK1/2 phosphorylation, thus enhancing cell survival. ALCAR therefore provides neuroprotection by stabilizing mitochondrial membrane, restoring the cholinergic transmission, and more importantly, it stimulates NGF receptors, thus triggering cell survival pathway via ERK phosphorylation. Therefore, ALCAR may be useful as an effective therapeutic agent for hypoxic stress and associated neurodegenerative diseases. © 2008 Wiley‐Liss, Inc.
Low‐density lipoproteins from embryonic cerebrospinal fluid are required for neural differentiation
Authors: Parada Carolina , Escolà‐Gil Joan Carles , Bueno David 
Published: May 2008

AbstractDuring development, embryonic cerebrospinal fluid(E‐CSF) is involved in cell survival, proliferation, and neurogenesis of the neuroepithelial progenitor cells. We have recently identified a complex pattern of proteins in chick and rat E‐CSF, which include apolipoproteins. Apolipoproteins play a critical role in the function of lipoproteins by interacting with receptors to deliver the lipid cargo to target cells. However, the function of these E‐CSF apolipoproteins is unclear. Here, we characterized the chick E‐CSF lipoprotein profile and analyzed the role of its lipoprotein fractions in neural differentiation. We found that the lipoprotein pattern of chick E‐CSF differed significantly from that of adult plasma, with a major proportion of apoB‐containing lipoproteins. Further, supplementation of lipoprotein‐depleted fraction with E‐CSF very low‐density lipoprotein (VLDL) and low‐density lipoprotein (LDL) resulted in 25% and 60%, respectively, of the neurogenesis induced by the whole E‐CSF in chick neuroepithelium explants, whereas high‐density lipoproteins caused the lowest induction. We further investigated the potential role of E‐CSF LDL in vivo by analyzing neural differentiation in the neuroepithelium of wild‐type (WT) and LDL receptor–knockout (LDLR KO) mouse embryos. E‐CSF lipids were mainly associated with LDL in both WT and LDLR KO mice, and the latter exhibited a substantial increase in LDL lipids compared with WT mice. Externally, LDLR KO embryos were apparently normal, and they exhibited up to 26% reduction in the number of neural differentiating cells in comparison with WT mice, although this finding was not statistically significant. These data strongly suggest that E‐CSF LDL plays a critical role during early neural differentiation. © 2008 Wiley‐Liss, Inc.
Microsomal epoxide hydrolase deletion enhances tyrosine hydroxylase phosphorylation in mice after MPTP treatment
Authors: Liu Mei , Hunter Randy , Nguyen Xuan V. , Kim Hyoung‐Chun , Bing Guoying 
Published: May 2008

AbstractParkinson's disease (PD) is the most prevalent neurodegenerative movement disorder. Epidemiological studies have suggested most cases of PD are linked to environmental risk factors. Microsomal epoxide hydrolase (mEH) is a conserved enzyme that catalyzes hydrolysis of a large number of epoxide intermediates such as drugs and epoxides of environmental toxins. We hypothesize that changes in mEH are involved in the pathogenesis of PD by modulating the vulnerability of dopaminergic neurons to environmental stress. Herein we reported that acute treatment with the neurotoxin MPTP (1‐methyl‐4‐phemyl‐1,2,3,6‐tetrahydropyridine) markedly increased the mEH immunoreactivity in the nigrostriatal system of C57BL/6 mice. Next, mEH knockout (KO) mice were used, and we found that tyrosine hydroxylase (TH)‐positive cell loss was significantly lower in the substantia nigra of mEH KO mice compared with wild‐type (WT) mice after MPTP treatment. The mean dopamine turnover ratios were significantly increased in MPTP‐treated mEH KO mice compared with WT. In addition, TH is the rate‐limiting enzyme for dopamine biosynthesis, and its activity is mainly regulated by TH phosphorylation at Ser‐31 (pSer31) and Ser‐40 (pSer40). Double immunofluorescence showed that both pSer31 and pSer40 are completely colocalized in total TH‐positive cells. However, immunoblotting confirmed that there was a significantly higher level of pSer31 in mEH‐KO mice when compared with WT mice after MPTP, and no marked differences among TH and its phosphorylation levels occurred after saline injection. These data suggested that mEH deficiency facilitates TH phosphorylation in the nigrostriatal dopamine system, which may be associated with an increased resistance of dopaminergic neurons to environmental toxins. © 2008 Wiley‐Liss, Inc.
Cytotoxic effect of azaspiracid‐2 and azaspiracid‐2‐methyl ester in cultured neurons: Involvement of the c‐Jun N‐terminal kinase
Authors: Vale Carmen , Wandscheer Carolina , Nicolaou K.C. , Frederick Michael O. , Alfonso Carmen , Vieytes Mercedes R. , Botana Luis M. 
Published: May 2008

AbstractHuman poisoning by azaspiracids (AZAs) has emerged as an increasing problem in Europe in recent years. Azaspiracid‐2 (AZA‐2) is one of the most abundant azaspiracids in nature. Although AZA‐2 was recently involved in several toxic episodes leading to human intoxications, there is no information available about its mechanism of action or its cytotoxic effect in cellular models. This paper reports on the neurotoxic effect of azaspiracid‐2 and its potential cellular targets. We explore the cellular and cytotoxic effects of AZA‐2 and AZA‐2‐methyl ester (where the carboxylic acid moiety of AZA‐2 was converted to the corresponding methyl ester) in cerebellar neurons. Pharmacological tools were used to analyze the role of different signal transduction pathways in the toxicity of AZA‐2. The neurotoxicity of AZA‐2 and AZA‐2‐methyl ester was developmentally regulated, exhibiting a higher cytotoxicity in younger cells (2–3 div). After excluding several signal transduction pathways, we found that inhibition of the mitogen‐activated protein kinase JNK completely prevented the cytotoxic effect of AZA‐2 in neurons. Furthermore, neuronal exposure to AZA‐2 or AZA‐2‐methyl ester caused an increase in the amount of total and phosphorylated JNK and produced nuclear accumulation of the protein. The results presented here point to a common target for AZA‐1 and AZA‐2 and constitute the first experimental approach to investigate the cytotoxicity of AZA‐2 in vitro, establishing an initial approach to probe the mechanism of action of these group of natural toxins. © 2008 Wiley‐Liss, Inc.
Effect of environmental enrichment on fearful behavior and gastrin‐releasing peptide receptor expression in the amygdala of prenatal stressed rats
Authors: Qian Jing , Zhou Dong , Pan Fang , Liu Chun‐xi , Wang Yu‐wei 
Published: May 2008

AbstractPrenatal stressed offspring exhibit more fearful behavior in behavioral tests, which can be reversed by environmental enrichment (EE). However, the physiological basis of these phenomena remains unclear. Previous studies revealed that abnormal fearful behavior of prenatally stressed offspring may be a consequence of increased activities of CRFergic systems (corticotropin‐releasing factor and its receptors) in the amygdala. Gastrin‐releasing peptide receptors (GRPR) also have an important role in regulating amygdala‐dependent, fear‐related learning. The aim of this study was to examine weather prenatal stress and EE can affect the expression of GRPR in the amygdala. We reported here that prenatal chronic stress (subjected to immobilization and bright light stress for 45 min three times per day) caused increased fearfulness in defensive withdrawal test but had no effect on the expression of GRPR in the amygdala. However, enriched environment housing treatment on postnatal days 21–60 can dramatically increase the expression of GRPR in amygdala and reduce fearfulness in the defensive withdrawal test. Our results demonstrate for the first time that EE can modify the expression of GRPR in the amygdala, which might contribute to our understanding of the physiological effects of environmental enrichment. © 2008 Wiley‐Liss, Inc.