bluuebunny/crossref_metadata_2025 huggingface dataset:
Monosynaptic Pathway from Rat Vibrissa Motor Cortex to Facial Motor Neurons Revealed by Lentivirus-Based Axonal Tracing
Authors: Grinevich Valery , Brecht Michael , Osten Pavel
Published: September 2005

The mammalian motor cortex typically innervates motor neurons indirectly via oligosynaptic pathways. However, evolution of skilled digit movements in humans, apes, and some monkey species is associated with the emergence of abundant monosynaptic cortical projections onto spinal motor neurons innervating distal limb muscles. Rats perform skilled movements with their whiskers, and we examined the possibility that the rat vibrissa motor cortex (VMC) projects monosynaptically onto facial motor neurons controlling the whisker movements. First, single injections of lentiviruses to VMC sites identified by intracortical microstimulations were used to label a distinct subpopulation of VMC axons or presynaptic terminals by expression of enhanced green fluorescent protein (GFP) or GFP-tagged synaptophysin, respectively. Four weeks after the injections, GFP and synaptophysin-GFP labeling of axons and putative presynaptic terminals was detected in the lateral portion of the facial nucleus (FN), in close proximity to motor neurons identified morphologically and by axonal back-labeling from the whisker follicles. The VMC projections were detected bilaterally, with threefold larger density of labeling in the contralateral FN. Next, multiple VMC injections were used to label a large portion of VMC axons, resulting in overall denser but still laterally restricted FN labeling. Ultrastructural analysis of the GFP-labeled VMC axons confirmed the existence of synaptic contacts onto dendrites and somata of FN motor neurons. These findings provide anatomical demonstration of monosynaptic VMC-to-FN pathway in the rat and show that lentivirus-based expression of GFP and GFP-tagged presynaptic proteins can be used as a high-resolution neuroanatomical tracing method.
Hedgehog AntagonistRENKCTD11Regulates Proliferation and Apoptosis of Developing Granule Cell Progenitors
Authors: Argenti Beatrice , Gallo Rita , Di Marcotullio Lucia , Ferretti Elisabetta , Napolitano Maddalena , Canterini Sonia , De Smaele Enrico , Greco Azzura , Fiorenza Maria Teresa , Maroder Marella , Screpanti Isabella , Alesse Edoardo , Gulino Alberto
Published: September 2005

During the early development of the cerebellum, a burst of granule cell progenitor (GCP) proliferation occurs in the outer external granule layer (EGL), which is sustained mainly by Purkinje cell-derived Sonic Hedgehog (Shh). Shh response is interrupted once GCPs move into the inner EGL, where granule progenitors withdraw proliferation and start differentiating and migrating toward the internal granule layer (IGL). Failure to interrupt Shh signals results in uncoordinated proliferation and differentiation of GCPs and eventually leads to malignancy (i.e., medulloblastoma). The Shh inhibitory mechanisms that are responsible for GCP growth arrest and differentiation remain unclear. Here we report thatREN, a putative tumor suppressor frequently deleted in human medulloblastoma, is expressed to a higher extent in nonproliferating inner EGL and IGL granule cells than in highly proliferating outer EGL cells. Accordingly, upregulated REN expression occurs along GCP differentiationin vitro, and, in turn, REN overexpression promotes growth arrest and increases the proportion of p27/Kip1+GCPs. REN also impairs both Gli2-dependent gene transcription and Shh-enhanced expression of the target Gli1 mRNA, thus antagonizing the Shh-induced effects on the proliferation and differentiation of cultured GCPs. Conversely, REN functional knock-down impairs Hedgehog antagonism and differentiation and sustains the proliferation of GCPs. Finally, REN enhances caspase-3 activation and terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling apoptotic GCP numbers; therefore, the pattern of REN expression, its activity, and its antagonism on the Hedgehog pathway suggest that this gene may represent a restraint of Shh signaling at the outer to inner EGL GCP transitions. Medulloblastoma-associated REN loss of function might withdraw such a limiting signal for immature cell expansion, thus favoring tumorigenesis.
Prediction of global VLE for mixtures with improved renormalization group theory
Authors: Mi Jianguo , Zhong Chongli , Li Yi‐Gui , Tang Yiping
Published: September 2005

The recently proposed renormalization group (RG) theory is reformulated within the context of density functional theory and applied to predicting global vapor–liquid equilibria (VLE) of Lennard–Jones chain pure fluids and fluid mixtures. An accurate equation based on the solution of the first‐order mean‐sphere approximation (FMSA) is adopted outside the critical region. Inside the critical region, the direct correlation function of FMSA is incorporated into the new RG transformation to describe the long‐range fluctuation, which is conformal to general inhomogeneous studies. The new RG theory is applied to correcting real mixture phase envelopes, as well as corresponding phase diagrams of pure compounds for the critical region. The calculated results are in substantial agreement with those from experiment and molecular simulation both inside and outside the critical region. The new method is highly predictive because no adjustable parameters and no mixing rule are needed for both model and real fluid mixtures. © 2005 American Institute of Chemical Engineers AIChE J, 2006
Long‐term results of hyperfractionated radiation and high‐dose intraarterial cisplatin for unresectable oropharyngeal carcinoma
Authors: Spring Paul M. , Valentino Joseph , Arnold Susanne M. , Sloan David , Kenady Daniel , Kudrimoti Mahesh , Haydon Richard C. , Lee Charles , Given Curtis , Mohiuddin Mohammed , Regine William F.
Published: September 2005

BACKGROUND

In this report, the authors present the results from a study of patients with unresectable oropharyngeal squamous cell carcinomas who were treated on a protocol of hyperfractionated radiation and high‐dose intraarterial cisplatin (HYPERRADPLAT) at the University of Kentucky.

METHODS

The study was designed as a prospective, single‐armed case series that was conducted in the setting of a single, academic, tertiary referral center. The patient cohort consisted of 24 previously untreated patients who were diagnosed with unresectable oropharyngeal carcinoma and were treated on the HYPERRADPLAT regimen, which included hyperfractionated external beam radiotherapy (1.2 grays [Gy] twice daily) was given for 5 weeks (60 Gy) followed by high‐dose intraarterial cisplatin (150 mg/m2) and sodium thiosulfate. Shrinking “large‐field” portals were started on Week 6 and finished on Week 7 with a cumulative dose of 76.8–81.6 Gy. The main outcome measures of the study were the primary and neck response rates, the 2‐year and 5‐year overall survival and disease‐specific survival rates, and acute and late treatment morbidity.

RESULTS

The median follow‐up was 77 months. Complete response rates at the primary and regional lymph nodes were both 88%. The 2‐year overall survival and disease‐specific survival rates were 57% and 68%, respectively; whereas the 5‐year overall survival and disease‐specific survival rates were 33% and 42%, respectively. Two patients had Grade 4 mucosal toxicity, and no patient experienced neurologic or significant hematologic toxicities. Within 1 year of treatment, 58% of patients had used a feeding tube.

CONCLUSIONS

The HYPERRADPLAT regimen produced excellent response rates and overall survival rates comparable to those achieved by patients who had unresectable oropharyngeal carcinomas. Tolerance of the therapy was good, and further studies using HYPERRADPLAT with induction therapy may improve outcomes further in this subset of patients with unfavorable disease. Cancer 2005. © 2005 American Cancer Society.
Perylene Dyes with High Resistance to Alkali
Authors: Langhals Heinz , Jaschke Harald , Bastani‐Oskoui Haleh , Speckbacher Markus
Published: September 2005

The attachment of a γ‐hydroxy alkyl group to a nitrogen atom of perylene‐3,4:9,10‐tetracarboxylic bisimides results in a persistency to alkaline hydrolysis, even to alkali alcoholates. The solubility of these dyes can be controlled by substituents in theβ‐position of the alkyl groups so that either highly stable pigments or dyes for homogeneous solutions with high fluorescence quantum yields are obtained. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
1,3‐Thiazoline‐5‐thiolates and 1,3‐Thiazole‐5(2H)‐thiones by [3+2]‐Cycloaddition of Carbon Disulfide to Metalated 4‐Alkylidene‐4H‐pyridin‐1‐ides
Authors: Hampe Diana , Görls Helmar , Anders Ernst
Published: September 2005

The 4‐alkylidene‐4H‐pyridin‐1‐ides 1(–), which are ambident anions derived from azomethines 1a–e, react easily with CS2 to yield the lithium 2,3‐dihydro‐1,3‐thiazole‐5‐thiolates 3a–e. Two mechanisms are basically possible for this cyclization: a concerted process similar to a 1,3‐dipolar cycloaddition or a two‐step reaction which starts with a Cα CS2 coupling and continues with a ring closure reaction to yield lithium thiazolidine‐5‐thiones 2. A proton migration from the Cα position to the previous imino N‐atom then follows to form the 2,3‐dihydro‐1,3‐thiazole‐5‐thiolates 3a–e. Protonation of 3 and a final oxidation of the intermediates 6 results in the formation of 1,3‐thiazole‐5(2H)‐thiones 7. This last step is always accompanied by a hydrolysis which results in 1,3‐thiazole‐5(2H)‐ones 8 as side products. In addition, a surprising byproduct 9 was found in the reaction of 1e with NaH and CS2 in pyridine. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Syntheses and Oligonucleotide Incorporation of Nucleoside Analogues Containing Pendant Imidazolyl or Amino Functionalities – The Search for Sequence‐Specific Artificial Ribonucleases
Authors: Holmes Stephen C. , Gait Michael J.
Published: September 2005

Oligonucleotide derivatives containing imidazolyl and amino functionalities have been proposed as artificial ribonucleases that might mimic the activities of RNase A but with greater sequence specificity. Such oligonucleotide reagents would have important applications as enhanced antisense reagents that obviate the need to recruit a cellular nuclease or nuclease complex. We present the syntheses of six nucleoside phosphoramidite analogues containing pendant protected imidazolyl or amino groups and their incorporation into oligonucleotides. We show that the six functionalised phosphoramidites have similar efficiencies of incorporation and present mass spectral evidence that the composition of an oligonucleotide library of 81 components is consistent with the expected mass mixture distribution. Such phosphoramidites are thus suitable starting materials for construction of mixed oligonucleotide libraries containing a region of imidazolyl and amino‐modified nucleotides ready for screening for sequence‐specific ribonuclease activity. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Synthesis of Annelated Azaheterocycles Containing a 5‐Carbamoylpyrazin‐3‐one Fragment by a Modification of the Four‐Component Ugi Reaction
Authors: Ilyin Alexey P. , Kobak Vladimir V. , Dmitrieva Irina G. , Peregudova Yulia N. , Kustova Veronika A. , Mishunina Yulia S. , Tkachenko Sergey E. , Ivachtchenko Alexandre V.
Published: September 2005

A convenient synthesis of novel imidazole‐ and pyrrole‐fused 1‐oxo‐1,2,3,4‐tetrahydropyrazine heterocyclic structures by a novel modification of the four‐component Ugi condensation is described. The usefulness and versatility of the developed approach for the synthesis of variously substituted compounds is demonstrated and the scope and limitations of the chemistry involved are discussed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Quadratic programming algorithm for wall slip and free boundary pressure condition
Authors: Wu C. W. , Sun H. X.
Published: September 2005

Wall slip is often observed in a highly sheared fluid film in a solid gap. This makes a difficulty in mathematical analysis for the hydrodynamic effect because fluid velocity at the liquid–solid interfaces is not known a priori. If the gap has a convergent–divergent wedge, a free boundary pressure condition, i.e. Reynolds pressure boundary condition, is usually used in the outlet zone in numerical solution. This paper, based on finite element method and parametric quadratic programming technique, gives a numerical solution technique for a coupled boundary non‐linearity of wall slip and free boundary pressure condition. It is found that the numerical error decreases with the number of elements in a negative power law having an index larger than 2. Our method does not need an iterative process and can simultaneously gives rise to fluid film pressure distribution, wall slip velocity and surface shear stress. Wall slip always decreases the hydrodynamic pressure. Large wall slip even causes a null hydrodynamic pressure in a pure sliding solid gap. Copyright © 2005 John Wiley & Sons, Ltd.
A study of the recirculating flow in planar, symmetrical branching channels
Authors: Tsui Yeng‐Yung , Lu Chih‐Yu
Published: September 2005

A numerical method is employed to examine the flow in symmetrical, two‐dimensional branches of Y shape and Tee shape. The methodology is based on a pressure‐correction procedure within the frame of unstructured grids. Specified pressures are imposed at the outlets of the two branches. The area ratio of the branch is allowed to vary in the range of 2–3. Separation of the flow in the bifurcating region is inevitable. With equal outlet pressures, symmetrical flow patterns prevail except for the Y type branch under the conditions of high Reynolds numbers and large area ratios. This implies that the Y‐branch flow is more sensitive to small disturbances. It is shown that with a slightly higher pressure imposed on one of the two branches the structure of the recirculating flow for the Y type is greatly affected and the flow rate is reduced dramatically in the high‐pressure branch channel. In contrast, the influence on the Tee type branch is much lower since the flow behaves like a jet impinging on a confined duct. Copyright © 2005 John Wiley & Sons, Ltd.
Consensus Proposals for a Unified System of Nomenclature of Hepatitis C Virus Genotypes *
Authors: Simmonds Peter , Bukh Jens , Combet Christophe , Deléage Gilbert , Enomoto Nobuyuki , Feinstone Stephen , Halfon Phillippe , Inchauspé Geneviève , Kuiken Carla , Maertens Geert , Mizokami Masashi , Murphy Donald G. , Okamoto Hiroaki , Pawlotsky Jean-Michel , Penin François , Sablon Erwin , Shin-I Tadasu , Stuyver Lieven J. , Thiel Heinz-Jürgen , Viazov Sergei , Weiner Amy J. , Widell Anders
Published: September 2005

International standardization and coordination of the nomenclature of variants of hepatitis C virus (HCV) is increasingly needed as more is discovered about the scale of HCV-related liver disease and important biological and antigenic differences that exist between variants. A group of scientists expert in the field of HCV genetic variability, and those involved in development of HCV sequence databases, the Hepatitis Virus Database (Japan), euHCVdb (France), and Los Alamos (United States), met to re-examine the status of HCV genotype nomenclature, resolve conflicting genotype or subtype names among described variants of HCV, and draw up revised criteria for the assignment of new genotypes as they are discovered in the future. A comprehensive listing of all currently classified variants of HCV incorporates a number of agreed genotype and subtype name reassignments to create consistency in nomenclature. The paper also contains consensus proposals for the classification of new variants into genotypes and subtypes, which recognizes and incorporates new knowledge of HCV genetic diversity and epidemiology. A proposal was made that HCV variants be classified into 6 genotypes (representing the 6 genetic groups defined by phylogenetic analysis). Subtype name assignment will be either confirmed or provisional, depending on the availability of complete or partial nucleotide sequence data, or remain unassigned where fewer than 3 examples of a new subtype have been described.
In conclusion
, these proposals provide the framework by which the HCV databases store and provide access to data on HCV, which will internationally coordinate the assignment of new genotypes and subtypes in the future. (Hepatology 2005.)
Subnuclear targeting of Runx1 Is required for synergistic activation of the myeloid specific M‐CSF receptor promoter by PU.1
Authors: Li Xiangen , Vradii Diana , Gutierrez Soraya , Lian Jane B. , van Wijnen Andre J. , Stein Janet L. , Stein Gary S. , Javed Amjad
Published: September 2005

Many types of acute myelogenous leukemia involve chromosomal translocations that target the C‐terminus of Runx1/AML1 transcription factor, a master regulator of hematopoiesis. The C‐terminus of Runx1/AML1 that includes the nuclear matrix targeting signal (NMTS) is essential for embryonic development, hematopoiesis, and target gene regulation. During the onset and normal progression of hematopoiesis, several lineage‐specific factors such as C/EBPα and PU.1 interact with Runx1 to regulate transcription combinatorially. Here we addressed the functional interplay between subnuclear targeting of Runx1 and gene activation during hematopoiesis. Point mutations were generated in the NMTS of the human Runx1 protein and tested for their effect on transcriptional cooperativity with C/EBPα and PU.1 at myeloid‐specific promoters. We characterized five mutants that do not alter nuclear import, DNA binding or C/EBPα‐dependent synergistic activation of the target gene promoters. However a critical tyrosine in the NMTS is required for subnuclear targeting and activation of the granulocyte‐macrophage colony stimulating factor (GM‐CSF) promoter. Furthermore, this point mutation is defective for transcriptional synergism with PU.1 on the macrophage colony stimulating factor (MCSF) receptor c‐FMS promoter. Our results indicate that the NMTS region of Runx1 is required for functional interactions with PU.1. Taken together, our findings establish that subnuclear targeting of Runx1 is a critical component of myeloid‐specific transcriptional control. © 2005 Wiley‐Liss, Inc.
Inhibition of low density lipoprotein receptor expression by long‐term exposure to phorbol ester via p38 mitogen‐activated protein kinase pathway
Authors: Oh Jiyoung , Choi Yon Sik , Kim Jun‐Woo , Park Joong‐Yeol , Kim Seung‐Whan , Park Kun‐Koo , Pak Youngmi Kim
Published: September 2005

The proximal region −234 to (+58 bp) of low‐density lipoprotein receptor (LDLR) is responsible for its up‐regulation by sterol regulatory element binding protein (SREBP). However, the mechanism of sterol‐independent repression of LDLR has not been determined yet. In this study, we observed that there was an early induction and a later repression of LDLR by phorbol ester (PMA) in SK‐Hep1 hepatocarcinoma cells and investigated the mechanisms through which PMA repressed LDLR transcription. SK‐Hep1 cells were exposed to PMA and LDLR mRNA was evaluated by RT‐PCR and Northern blot analysis. The effect of phorbol ester on LDLR transcriptional activity was studied using transient transfection of LDLR promoter‐luciferase constructs. Overexpression of N‐SREBP‐2, a dominant positive SREBP2, did not reverse the PMA‐repressed LDLR promoter activity. Serial deletion of LDLR promoter revealed that the region between −1,563 and −1,326 was responsible for the repression. The pretreatment with SB202190, an inhibitor for p38 mitogen‐activated protein kinase pathway (p38‐MAPK), but not other signaling inhibitors, reversed the PMA‐induced repression. The 24 h‐treatment with PMA efficiently arrested the SK‐Hep1 cell cycle at G0/G1 as demonstrated by FACS analysis and decreased the 3H‐thymidine incorporation. The PMA‐induced repression of LDLR transcription may be exerted by the factor(s), not SREBP2, induced or modified by p38‐MAPK‐mediated signaling pathway and associated with cell cycle blockage. © 2005 Wiley‐Liss, Inc.
Nicotinic and PDGF‐receptor function are essential for nicotine‐stimulated mitogenesis in human vascular smooth muscle cells
Authors: Pestana Ivo A. , Vazquez‐Padron Roberto I. , Aitouche Abdelouahab , Pham Si M.
Published: September 2005

Cigarette smoking is implicated in the formation of occlusive vascular diseases. Nicotine's role in this process is incompletely understood. Nicotine's effect on human aortic vascular smooth muscle cells (HaVSMC) and the role of the nicotinic receptor (nAChR), platelet‐derived growth factor (PDGF), and the PDGF‐receptor (PDGF‐R) in this response were studied. Nicotine's mitogenic effect was characterized by three methods: thymidine incorporation, a viability/proliferation assay based on metabolic conversion of tetrazolium salt to formazan dye and cell counting. Nicotine administration (10−6 M) stimulated cell cycle entry marked by increased DNA synthesis, PCNA and cyclin D1 production, and increased cell division. Nicotinic receptor blockade with d‐tubocurarine, a nicotinic AchR blocker, decreased nicotine‐induced DNA synthesis, and cell division (0.33 ± 0.04, 0.77 ± 0.31‐fold decrease, respectively). Nicotine increased cellular PDGF‐BB transcript levels and protein release (ELISA: 1.6 ± 0.5‐fold increase) but not PDGF‐AA or PDGF–AB release. Nicotine increased PDGFβ‐receptor protein content. PDGF inactivation with anti‐PDGF antibody abolished nicotine‐induced DNA synthesis (1.9 ± 0.08‐fold decrease). PDGF‐R blockade with the PDGF‐R antagonist tyrphostin AG 1295 decreased nicotine‐induced DNA synthesis and cell division (0.25 ± 0.01, 0.44 ± 0.2‐fold decrease, respectively). PDGF‐R blockade reversed nicotine‐stimulated increases in PDGF release, PDGF‐BB transcripts, and PDGF‐receptor levels (0.68 ± 0.34; 0.46 ± 0.01; 0.28 ± 0.01‐fold decrease, respectively). In conclusion, nicotine‐mediated activation of nAChRs increases PDGF‐BB transcription and protein production as well as PDGF β‐receptor levels. PDGF‐BB/PDGF‐R interaction is vital in nicotine's mitogenic actions on human aortic smooth muscle cells. J. Cell. Biochem. © 2005 Wiley‐Liss, Inc.
Optimized transfection of diced siRNA into mature primary human osteoclasts: Inhibition of cathepsin K mediated bone resorption by siRNA
Authors: Selinger Christina I. , Day Christopher J. , Morrison Nigel A.
Published: September 2005

Osteoclasts are large multinucleated cells responsible for bone resorption. Bone resorption is dependent on the liberation of calcium by acid and protease destruction of the bone matrix by proteinases. The key proteinase produced by the osteoclast is cathepsin K. Targeted knock‐down of cathepsin K was performed using small inhibitory RNA (siRNA). siRNA is a method that introduces short double‐stranded RNA molecules that instruct the RNA‐induced silencing complex (RISC) to degrade mRNA species complementary to the siRNA. Transfection of siRNA by lipid cations allows for short‐term inhibition of expression of the targeted gene. We show that transfection of primary human osteoclasts with siRNA to cathepsin K reduces expression by ≥60% and significantly inhibits bone resorption with a reduction of both resorption pit numbers (P = 0.018) and resorbed area (P = 0.013). We also show that FuGENE 6 is an effective lipid transfection reagent with which to transfect primary human osteoclasts, that does not produce off‐target effects. © 2005 Wiley‐Liss, Inc.
Reduced alpha adrenergic mediated contraction of renal preglomerular blood vessels as a function of gender and aging
Authors: Passmore John C. , Joshua Irving G. , Rowell Peter P. , Tyagi Suresh C. , Falcone Jeff C.
Published: September 2005

As human males age, a decline in baroreflex‐mediated elevation of blood pressure occurs due, at least in part, to a reduction in alpha‐1 adrenergic vasoconstrictor function. Alpha adrenergic constriction is mediated by guanosine triphosphate binding Protein (G Protein) coupled signaling pathways. Alpha‐1 A/C, B, and D adrenergic receptor expressions, measured by GeneChip array, are not reduced during aging in renal blood vessels of male or female rats. Alpha‐1 A GeneChip expression is greater, at all ages studied, in females than in males. Prazosin binding by alpha‐1 adrenergic receptors is greater in young adult female rats than in young adult male rats; however, it is reduced with aging in both male and female rats. G alpha q GeneChip expression declines while expression of adrenergic receptor kinase (GRK2) and tyrosine phosphatases (TyrP) increase with aging in male rats. The declines in alpha‐1 adrenergic receptor binding and G alpha q expression and also the increases in GRK2 and TyrP expression likely relate to the age‐related decline of vasoconstriction in male rats. The information that the expression of alpha‐1 A adrenergic receptors is greater in female rats and (GRK2) expression does not increase during aging could relate to the gender differences in vasoconstrictor function with aging. Gene therapy to ameliorate the age‐related decline in renal function could possibly reduce the need for renal dialysis. Signaling pathways such as those reviewed herein may provide an outline of the molecular pathways needed to move toward successful renal gene therapy for aging individuals. J. Cell. Biochem. © 2005 Wiley‐Liss, Inc.
Advances in understanding bone cancer pain
Authors: Goblirsch M.J. , Zwolak P. , Clohisy D.R.
Published: September 2005

Experimental animal models of bone cancer pain have emerged and findings have provided a unique glimpse into unraveling the mechanism that drives this debilitating condition. Key contributors to the generation and maintenance of bone cancer pain are tumor‐induced osteolysis, tumor itself, and production of nociceptive mediators in the bone‐tumor microenvironment. J. Cell. Biochem. © 2005 Wiley‐Liss, Inc.
Histone acetylase inhibitor trichostatin A induces acetylcholinesterase expression and protects against organophosphate exposure
Authors: Curtin Bryan F. , Tetz Lauren M. , Compton Jaimee R. , Doctor Bhupendra P. , Gordon Richard K. , Nambiar Madhusoodana P.
Published: September 2005

The biological effects of organophosphorous (OP) chemical warfare nerve agents (CWNAs) are exerted by inhibition of acetylcholinesterase (AChE), which prevents the hydrolysis of the neurotransmitter acetylcholine, leading to hypercholinergy, seizures/status epilepticus, respiratory/cardiovascular failure, and potentially death. Current investigations show that bioscavenger therapy using purified fetal bovine AChE in rodents and non‐human primates and the more recently tested human butyrylcholinesterase, is a promising treatment for protection against multiple LD50 CWNA exposures. Potential impediments, due to the complex structure of the enzyme, purification effort, resources, and cost have necessitated alternative approaches. Therefore, we investigated the effects of transcriptional inducers to enhance the expression of AChE to achieve sufficient protection against OP poisoning. Trichostatin A (TSA), an inhibitor of histone deacetylase that de‐condenses the chromatin, thereby increasing the binding of transcription factors and mRNA synthesis, was evaluated for induction of AChE expression in various neuronal cell lines. Dose‐response curves showed that a concentration of 333 nM TSA was optimal in inducing AChE expression. In Neuro‐2A cells, TSA at 333 nM increased the extracellular AChE activity approximately 3–4 fold and intracellular enzyme activity 10‐fold. Correlating with the AChE induction, TSA pre‐treatment significantly protected the cells against exposure to the organophosphate diisopropylfluorophosphate, a surrogate for the chemical warfare agents soman and sarin. These studies indicate that transcriptional inducers such as TSA up‐regulate AChE, which then can bioscavenge any organophosphates present, thereby protecting the cells from OP‐induced cytotoxicity. In conclusion, transcriptional inducers are prospective new methods to protect against CWNA exposure. © 2005 Wiley‐Liss, Inc.
Regulation of human prostate‐specific G‐protein coupled receptor, PSGR, by two distinct promoters and growth factors
Authors: Weng Jinsheng , Ma Wenbin , Mitchell Dianne , Zhang Jianshe , Liu Mingyao
Published: September 2005

PSGR is a newly identified human prostate tissue‐specific gene belonging to the G‐protein coupled receptor (GPCR) family. Overexpression of PSGR is associated with human prostate intraepithelial neoplasia (PIN) and prostate tumors, suggesting PSGR may play an important role in early prostate cancer development and progression. To understand the regulation of tissue‐specific expression of human PSGR and its upregulation mechanism in prostate cancers, we characterized the promoter region of PSGR and analyzed the control mechanism for PSGR expression in human prostate tissues/cells. In this report, we demonstrate that two distinct promoters control the transcriptional regulation of PSGR in human prostate cells. The first promoter region includes exon 1 and a TATA box at −31 site. The minimal DNA sequence with promoter activity is about 123 bp upstream of exon 1. Exon 1 contains tissue specific regulatory activity for the first promoter of PSGR gene. The second promoter is located in the upstream region of exon 2, which is a TATA‐less and non‐GC‐rich promoter. Primer extension and RNA protection assays (RPA) revealed that the transcription driven by the second promoter is initiated at the junction of intron and exon 2 within a cluster of nucleotides located about 250 bp upstream from the junction. Both promoters show prostate cell‐specific characteristics in our luciferase assays in transfected cells. Furthermore, we investigated the regulation of the promoter activities of the PSGR gene by different growth factors and cytokines, and demonstrated that interleukin‐6 (IL‐6) activates the promoter activities of PSGR in human prostate cancer cells. These data suggest that two functional promoters regulate the transcriptional expression of PSGR in human prostate tissues and PSGR is a new target for IL‐6 transcriptional regulation. J. Cell. Biochem. © 2005 Wiley‐Liss, Inc.
Endothelin‐1 induces proliferation of human lung fibroblasts and IL‐11 secretion through an ETA receptor‐dependent activation of map kinases
Authors: Gallelli Luca , Pelaia Girolamo , D'Agostino Bruno , Cuda Giovanni , Vatrella Alessandro , Fratto Donatella , Gioffrè Vincenza , Galderisi Umberto , De Nardo Marilisa , Mastruzzo Claudio , Salinaro Elisa Trovato , Maniscalco Mauro , Sofia Matteo , Crimi Nunzio , Rossi Francesco , Caputi Mario , Costanzo Francesco S. , Maselli Rosario , Marsico Serafino A. , Vancheri Carlo
Published: September 2005

Endothelin‐1 (ET‐1) is implicated in the fibrotic responses characterizing interstitial lung diseases, as well as in the airway remodeling process occurring in asthma. Within such a context, the aim of our study was to investigate, in primary cultures of normal human lung fibroblasts (NHLFs), the ET‐1 receptor subtypes, and the intracellular signal transduction pathways involved in the proliferative effects of this peptide. Therefore, cells were exposed to ET‐1 in the presence or absence of an overnight pre‐treatment with either ETA or ETB selective receptor antagonists. After cell lysis, immunoblotting was performed using monoclonal antibodies against the phosphorylated, active forms of mitogen‐activated protein kinases (MAPK). ET‐1 induced a significant increase in MAPK phosphorylation pattern, and also stimulated fibroblast proliferation and IL‐6/IL‐11 release into cell culture supernatants. All these effects were inhibited by the selective ETA antagonist BQ‐123, but not by the specific ETB antagonist BQ‐788. The stimulatory influence of ET‐1 on IL‐11, but not on IL‐6 secretion, was prevented by MAPK inhibitors. Therefore, such results suggest that in human lung fibroblasts ET‐1 exerts a profibrogenic action via an ETA receptor‐dependent, MAPK‐mediated induction of IL‐11 release and cell proliferation. © 2005 Wiley‐Liss, Inc.
Genistein‐induced neuronal differentiation is associated with activation of extracellular signal‐regulated kinases and upregulation of p21 and N‐cadherin
Authors: Hung S.P. , Hsu J.R. , Lo C.P. , Huang H.J. , Wang J.P. , Chen S.T.
Published: September 2005

Neuronal differentiation in the mammalian CNS is driven by multiple events. When treated with retinoic acid (RA), hNTera‐2 (NT‐2) cells undergo postmitotic neuronal differentiation. Here, we show that a prolonged exposure of NT‐2 cells with non‐cytotoxic doses of genistein, a protein tyrosine kinase (PTK) inhibitor, induced differentiation of NT‐2 cells. Additionally, genistein enhanced RA‐induced neuronal differentiation by increasing the activation of extracellular signal‐related kinase 1/2 (ERK1/2) via phosphorylation at Thr183 and Tyr185 in 3–7 days. Meanwhile, genistein also upregulated N‐cadherin and p21 (a Cdk inhibitor), but downregulated proliferating cell nuclear antigen protein (PCNA). MEK1/2 inhibitors, such as PD98059 and U0126, reduced RA‐induced ERK1/2 activity, but could not block the genistein effects. Our observations indicate that genistein‐induced neuronal differentiation is not dependent of the MEK‐ERK signaling cascade. Instead, genistein‐upregulated ERK activation is likely due to this chemical's direct effect on chromosome and gene transcription, rather than its inhibition on tyrosine kinases. Failure of inhibition of ERK1/2 activation by the MEK1/2 inhibitors PD98059 and U0126 suggests presence of an unknown activator for ERK1/2 in neuronal cells. J. Cell. Biochem. © 2005 Wiley‐Liss, Inc.
A fast and sensitive 1H NMR method to measure the turnover of the H2 hydrogen of lactate
Authors: Rodrigues Tiago B. , Cerdán Sebastián
Published: September 2005

A fast and sensitive procedure to determine the turnover of the H2 hydrogen of lactate and quantify its 2H‐enrichment by 1H NMR is illustrated using C6 cells metabolizing (3‐13C) lactate in 50% 2H2O (vol/vol). 2H substitution of the lactate H2 hydrogen resulted in two easily detectable transformations of the vicinal H3 doublet resonance: 1) the formation of an H3 singlet due to the disappearance of the homonuclear coupling to H2 (3JβH‐αH = 7.0 Hz), and 2) an upfield isotopic shift derived from the vicinal 2H2 substitution (Δ3 = –0.007 ppm). Only those lactate molecules that have passed through the cell cytosol experience these effects, since H2 deuteration involves lactate dehydrogenase activity and NAD(2H). Thus, analysis of the observed shifted and unshifted H3 lactate resonances from the incubation medium allows the discrimination of the perprotonated (3‐13C) lactate added as substrate, and the (3‐13C, 2‐2H) lactate recycled to the incubation medium after passage through the cytosol. Magn Reson Med, 2005. © 2005 Wiley‐Liss, Inc.
Continuously moving table MRI with SENSE: Application in peripheral contrast enhanced MR angiography
Authors: Hu Houchun H. , Madhuranthakam Ananth J. , Kruger David G. , Glockner James F. , Riederer Stephen J.
Published: September 2005

An integration of SENSitivity Encoding (SENSE) with continuously moving table (CMT) MRI for extended field‐of‐view (FOV) acquisitions is described. In this work, the approach in which receiver coils are attached to the object and move in synchrony with the scanner table is considered. Technical issues dealing with the implementation of SENSE‐CMT are addressed, including coil calibration, correction for non‐uniform magnetic gradients, and specific reconstruction steps. An explanation of combining SENSE with gradient non‐linearity correction is given, as the latter becomes necessary in CMT acquisitions where a large sampling FOV is used. It is hypothesized that SENSE can provide at least a 2‐fold improvement in lateral spatial resolution compared to non‐accelerated CMT acquisitions. The hypothesis is tested in phantoms, where the effectiveness of both SENSE and gradient non‐linearity correction to improve spatial resolution is shown. The SENSE‐CMT technique is further demonstrated in vivo with contrast‐enhanced MR angiography of the peripheral vasculature. Magn Reson Med, 2005. © 2005 Wiley‐Liss, Inc.
Convergence behavior of iterative SENSE reconstruction with non‐Cartesian trajectories
Authors: Qu Peng , Zhong Kai , Zhang Bida , Wang Jianmin , Shen Gary X.
Published: September 2005

In non‐Cartesian SENSE reconstruction based on the conjugate gradient (CG) iteration method, the iteration very often exhibits a “semi‐convergence” behavior, which can be characterized as initial convergence toward the exact solution and later divergence. This phenomenon causes difficulties in automatic implementation of this reconstruction strategy. In this study, the convergence behavior of the iterative SENSE reconstruction is analyzed based on the mathematical principle of the CG method. It is revealed that the semi‐convergence behavior is caused by the ill‐conditioning of the underlying generalized encoding matrix (GEM) and the intrinsic regularization effect of CG iteration. From the perspective of regularization, each iteration vector is a regularized solution and the number of iterations plays the role of the regularization parameter. Therefore, the iteration count controls the compromise between the SNR and the residual aliasing artifact. Based on this theory, suggestions with respect to the stopping rule for well‐behaved reconstructions are provided. Simulated radial imaging and in vivo spiral imaging are performed to demonstrate the theoretical analysis on the semi‐convergence phenomenon and the stopping criterion. The dependence of convergence behavior on the undersampling rate and the noise level in samples is also qualitatively investigated. Magn Reson Med, 2005. © 2005 Wiley‐Liss, Inc.
Tunnel stability analysis during construction using a neuro‐fuzzy system
Authors: Luis Rangel José , Iturrarán‐Viveros Ursula , Gustavo Ayala A. , Cervantes Francisco
Published: September 2005

This paper presents an alternative strategy to evaluate the stability of tunnels during the design and construction stages based on a hybrid system, composed by neural, neuro‐fuzzy and analytical solutions. A prototype of this system is designed using a database formed by 261 cases, 45 real and the rest synthetic. This system is capable of reproducing the displacements induced at the periphery of the tunnel before and after support installation. The stability of the excavation process is evaluated using a criterion that considers dimensionless parameters based on the shear strength of the media, the induced deformation level in the ground, the plastic radii and the advance of excavation without support. The efficiency and validity of the prototype is verified with two examples of actual tunnels, one included in the database used to train the system and the other not included. The results of both examples show a better approximation than other commonly used techniques. Copyright © 2005 John Wiley & Sons, Ltd.
Interaction between different internal length scales in strain localization analysis of fully and partially saturated porous media—the 1‐D case
Authors: Schrefler B.A. , Zhang H.W. , Sanavia L.
Published: September 2005

The paper analyses the interaction between two internal length scales during dynamic strain localization in multiphase porous materials. The first internal length is introduced in the mathematical model by the gradient‐dependent plasticity for the solid skeleton, while the second one is naturally contained in the multiphase model and is due to the seepage process of the water via Darcy's law, which induces a rate‐dependent behaviour of the solid skeleton. Numerical results of a one‐dimensional example of water saturated porous medium demonstrate the competing effect between these two length scales. The porous medium is here treated as a multiphase continuum, with the pores filled by water and air, the last one at constant atmospheric pressure. Copyright © 2005 John Wiley & Sons, Ltd.
A 3D beam‐to‐beam contact finite element for coupled electric–mechanical fields
Authors: Boso D. P. , Litewka P. , Schrefler B. A. , Wriggers P.
Published: September 2005

In this paper the formulation of an electric–mechanical beam‐to‐beam contact element is presented. Beams with circular cross‐sections are assumed to get in contact in a point‐wise manner and with clean metallic surfaces. The voltage distribution is influenced by the contact mechanics, since the current flow is constricted to small contacting spots. Therefore, the solution is governed by the contacting areas and hence by the contact forces. As a consequence the problem is semi‐coupled with the mechanical field influencing the electric one. The electric–mechanical contact constraints are enforced with the penalty method within the finite element technique. The virtual work equations for the mechanical and electric fields are written and consistently linearized to achieve a good level of computational efficiency with the finite element method. The set of equations is solved with a monolithic approach. Copyright © 2005 John Wiley & Sons, Ltd.
On the effectiveness of variation in the physical variables on the steady MHD flow between parallel plates with heat transfer
Authors: Attia Hazem Ali
Published: September 2005

The influence of variation in physical variables on the steady Hartmann flow with heat transfer is studied. An external uniform magnetic field is applied perpendicular to the parallel plates and the fluid is acted upon by a constant pressure gradient. The viscosity and the thermal and electric conductivities are assumed to be temperature dependent. The two plates are kept at two constant but different temperatures and the viscous and Joule dissipations are considered in the energy equation. A numerical solution for the governing non‐linear coupled equations of motion and the energy equation is obtained. The effect of magnetic field, the temperature dependent viscosity, thermal conductivity, and electric conductivity on both the velocity and temperature distributions is examined. Copyright © 2005 John Wiley & Sons, Ltd.
Analysis of singular stress fields at multi‐material corners under thermal loading
Authors: Song Chongmin
Published: September 2005

The scaled boundary finite‐element method is extended to the modelling of thermal stresses. The particular solution for the non‐homogeneous term caused by thermal loading is expressed as integrals in the radial direction, which are evaluated analytically for temperature changes varying as power functions of the radial coordinate. When applied to model a multi‐material corner, only the boundary of the problem domain is discretized. The boundary conditions on the straight material interfaces and the side‐faces forming the corner are satisfied analytically without discretization. The stress field is expressed semi‐analytically as a series solution. The stress distribution along the radial direction, including both the real and complex power singularity and the power‐logarithmic singularity, is represented analytically. The stress intensity factors are determined directly from their definitions in stresses. No knowledge on asymptotic expansions is required. Numerical examples are calculated to evaluate the accuracy of the scaled boundary finite‐element method. Copyright © 2005 John Wiley & Sons, Ltd.
A new fast multipole boundary element method for solving large‐scale two‐dimensional elastostatic problems
Authors: Liu Yijun
Published: September 2005

A new fast multipole boundary element method (BEM) is presented in this paper for large‐scale analysis of two‐dimensional (2‐D) elastostatic problems based on the direct boundary integral equation (BIE) formulation. In this new formulation, the fundamental solution for 2‐D elasticity is written in a complex form using the two complex potential functions in 2‐D elasticity. In this way, the multipole and local expansions for 2‐D elasticity BIE are directly linked to those for 2‐D potential problems. Furthermore, their translations (moment to moment, moment to local, and local to local) turn out to be exactly the same as those in the 2‐D potential case. This formulation is thus very compact and more efficient than other fast multipole approaches for 2‐D elastostatic problems using Taylor series expansions of the fundamental solution in its original form. Several numerical examples are presented to study the accuracy and efficiency of the developed fast multipole BEM formulation and code. BEM models with more than one million equations have been solved successfully on a laptop computer. These results clearly demonstrate the potential of the developed fast multipole BEM for solving large‐scale 2‐D elastostatic problems. Copyright © 2005 John Wiley & Sons, Ltd.
Determination of the site‐specific and isoform‐specific glycosylation in human plasma‐derived antithrombin by IEF and capillary HPLC‐ESI‐MS/MS
Authors: Plematl Alexander , Demelbauer Uwe M. , Josic Djuro , Rizzi Andreas
Published: September 2005

The glycan structures of the major and more than ten minor populated isoforms of antithrombin (AT) were determined after separation of the isoforms by IEF using IPG strips. The bands excised from the gel were reduced, derivatized by iodoacetamide and submitted to tryptic digestion. The digest was analyzed by RP‐HPLC‐ESI‐MS equipped with a quadrupole ion‐trap mass analyzer. MS/MS experiments allowed establishing the monosaccharide compositions in the glycopeptides. For the major isoform of α‐AT four identical biantennary glycans with two terminal sialic acids (SA) each, a total of eight SA, were found in full agreement with the literature. In the IEF‐band containing this major isoform (pI 5.18) a further, much less abundant, isoform was detected showing a fucosylation on the glycan attached to Asn155 but being of otherwise identical structure as described above. The isoforms with pI 5.10 were found to include one triantennary glycan, all antennas carrying terminal SA. The occurrence of triantennary structure is site specific, involving the peptides with Asn135 and Asn155, alternately. At pI 5.24 we found those four isoforms that carry the glycans like the main‐isoform of α‐AT but missing one terminal SA. There was no site specificity found for the mono‐sialo structure. The isoform at pI 5.31 is the major isoform of β‐AT containing three identical biantennary structures being fully sialylated. No isoforms (above 0.5% abundance) with two glycans only or three glycans other than β‐AT were detected. Fucosylation was found in the main isoform with an abundance of about 5%, and as expected with all the other isoforms with a comparable abundance.
Comparative proteomic analysis using samples obtained with laser microdissection and saturation dye labelling
Authors: Wilson Kate E. , Marouga Rita , Prime John E. , Pashby D. Paul , Orange Paul R. , Crosier Steven , Keith Alexander B. , Lathe Richard , Mullins John , Estibeiro Peter , Bergling Helene , Hawkins Edward , Morris Christopher M.
Published: September 2005

Comparative proteomic methods are rapidly being applied to many different biological systems including complex tissues. One pitfall of these methods is that in some cases, such as oncology and neuroscience, tissue complexity requires isolation of specific cell types and sample is limited. Laser microdissection (LMD) is commonly used for obtaining such samples for proteomic studies. We have combined LMD with sensitive thiol‐reactive saturation dye labelling of protein samples and 2‐D DIGE to identify protein changes in a test system, the isolated CA1 pyramidal neurone layer of a transgenic (Tg) rat carrying a human amyloid precursor protein transgene. Saturation dye labelling proved to be extremely sensitive with a spot map of over 5,000 proteins being readily produced from 5 μg total protein, with over 100 proteins being significantly altered at p < 0.0005. Of the proteins identified, all showed coherent changes associated with transgene expression. It was, however, difficult to identify significantly different proteins using PMF and MALDI‐TOF on gels containing less than 500 μg total protein. The use of saturation dye labelling of limiting samples will therefore require the use of highly sensitive MS techniques to identify the significantly altered proteins isolated using methods such as LMD.