bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrophoretic mobility of linear and star‐branched DNA in semidilute polymer solutions
Authors: Saha Sourav , Heuer Daniel M. , Archer Lynden A. 
Published: July 2006

AbstractElectrophoresis of large linear T2 (162 kbp) and 3‐arm star‐branched (NArm = 48.5 kbp) DNA in linear polyacrylamide (LPA) solutions above the overlap concentration c* has been investigated using a fluorescence visualization technique that allows both the conformation and mobility μ of the DNA to be determined. LPA solutions of moderate polydispersity index (PI ∼ 1.7–2.1) and variable polymer molecular weight Mw (0.59–2.05 MDa) are used as the sieving media. In unentangled semidilute solutions (c*<c<ce), we find that the conformational dynamics of linear and star‐branched DNA in electric fields are strikingly different; the former migrating in predominantly U‐ or I‐shaped conformations, depending on electric field strength E, and the latter migrating in a squid‐like profile with the star‐arms outstretched in the direction opposite to E and dragging the branch point through the sieving medium. Despite these visual differences, μ for linear and star‐branched DNA of comparable size are found to be nearly identical in semidilute, unentangled LPA solutions. For LPA concentrations above the entanglement threshold (c>ce), the conformation of migrating linear and star‐shaped DNA manifest only subtle changes from their unentangled solution features, but μ for the stars decreases strongly with increasing LPA concentration and molecular weight, while μ for linear DNA becomes nearly independent of c and Mw. These findings are discussed in the context of current theories for electrophoresis of large polyelectrolytes.
Inflammation stimulates myelination by transplanted oligodendrocyte precursor cells
Authors: Setzu Anna , Lathia Justin D. , Zhao Chao , Wells Karen , Rao Mahendra S. , ffrench‐Constant Charles , Franklin Robin J. M. 
Published: July 2006

AbstractInflammation associated with CNS demyelination provides an important stimulus for the activation of endogenous oligodendrocyte precursor cells (OPCs) and subsequent remyelination. This view is largely based on “loss‐of‐function” studies, whereby remyelination is impaired following depletion of inflammatory cells or mediators. However, “gain‐of‐function” approaches, asking whether inflammation directly enhances remyelination, have received less attention. We have addressed this issue using a model in which OPCs transplanted into the adult rat retina myelinate retinal ganglion cell axons around the point of injection. Inflammation (characterized by increased expression of the macrophage marker ED1 and the astrocyte marker GFAP, and the up‐regulation of multiple cytokines) was induced in the retina by the administration of the TLR‐2 ligand zymosan. Myelination, revealed by MBP+ myelin sheaths, was substantially increased when OPCs were injected into the inflamed retina compared to that achieved following transplantation into the normal, noninflamed retina. Our results have important implications for the development of immunomodulatory treatments for acute demyelinating disease and for the therapeutic creation of proremyelination environments in chronic demyelinating disease. © 2006 Wiley‐Liss, Inc.
Regulation of the astrocyte resting membrane potential by cyclic AMP and protein kinase A
Authors: Bolton Sally , Greenwood Kirsty , Hamilton Nicola , Butt Arthur M. 
Published: July 2006

AbstractThe factors regulating astroglial resting membrane potential (RMP) are unresolved. Here, we have examined developmental, morphological, and intracellular factors that may regulate the RMP in astrocytes of isolated intact optic nerves of rats and mice aged postnatal day (P3) to adult. The astroglial RMP ranged from −25 to −85 mV, independent of age and morphological phenotype. There was a developmental negative shift in the astroglial RMP from a non‐Gaussian distribution in perinatal nerves, to a bimodal distribution of RMPs after P15, with peaks at −52 and −74 mV in adults. Blockade of Kir with 100 μM BaCl2 significantly depolarized the RMP to −30 mV; the RMP was unaffected by TEA or agents that modulated ATP‐sensitive potassium channels. Raising intracellular cyclic AMP (cAMP) with dbcAMP or forskolin induced a significant hyperpolarization by ∼15 mV, whereas inhibition of cAMP‐dependent protein kinase (PKA) depolarized the astroglial RMP to −40 mV. The hyperpolarizing action of dbcAMP was blocked by 100 μM BaCl2. The effects of BaCl2 indicate that the developmental negative shift in the RMP and the cAMP‐mediated hyperpolarization were dependent on Kir. This study provides evidence that the heterogeneous RMP of mature astrocytes is regulated by cAMP and PKA signaling. © 2006 Wiley‐Liss, Inc.
Treatment of cremaster synkinesias with botulinum toxin A: A video case report
Authors: Ritter Martin A. , Frese Achim , Dziewas Rainer , Knecht Stefan , Evers Stefan 
Published: July 2006

AbstractSynkinesias secondary to nerve lesions and aberrant re‐innervation are well‐known phenomena especially after lesions of the facial nerve. Synkinesias can successfully be treated with botulinum toxin A (BTx A). Synkinesias of the cremaster muscle have not been described or treated to date. We present the case of a 62‐year‐old man who developed synkinesias of both cremaster muscles after extensive laparatomy for esophageal cancer. Treatment of synkinesias with various oral medications had been unsuccessful. Electromyography‐guided injections of BTx A in both cremaster muscles (15 MU on the right and 10 on the left) led to significant symptom relief for an average of 8 weeks. We present the case including pre‐ and posttreatment video clips. © 2006 Movement Disorder Society
Reduced potency after refrigerated storage of botulitum toxin A: Human extensor digitorum brevis muscle study
Authors: Paik Nam‐Jong , Seo Kyle , Eun Hee Chul 
Published: July 2006

AbstractTo determine whether the potency of botulinum toxin A (BTA) decreases after being reconstituted with normal saline and stored in refrigerator, we injected one side of the extensor digitorum brevis muscle with 2.5 units of botulinum toxin A that had been immediately reconstituted with saline, and the contralateral side with identical material that had been reconstituted and stored in a refrigerator for preselected periods (1, 2, and 4 weeks) in 32 healthy volunteers. Mean compound muscle action potential amplitudes expressed as a percentage of the baseline amplitude were more reduced in sides injected with immediately reconstituted BTA than in sides injected with BTA stored for 1 week or more (P < 0.05). No bacterial growth was observed in any stored BTA samples. Storage of reconstituted BTA at low temperatures may affect the potency of the toxin. Therefore, the use of BTA after refrigerated storage is not recommended. © 2006 Movement Disorder Society
Recurrent dystonia in homocystinuria: A metabolic pathogenesis
Authors: Sinclair Alex J. , Barling Lucy , Nightingale Simon 
Published: July 2006

AbstractDystonia complicating homocystinuria is extremely rare in the absence of thromboembolic disease. We report a unique case of recurrent dystonia in a patient with homocystinuria secondary to pyridoxine‐unresponsive cystathionine β‐synthase deficiency. Brain MRI was normal. Two biochemical markers for homocystinuria, homocystine and methionine, were markedly elevated during periods when our patient manifested dystonia. These findings suggest that accumulation of sulfur‐containing amino acids may contribute to the pathophysiology of dystonia in patients with homocystinuria. © 2006 Movement Disorder Society
Effects of tyramine administration in Parkinson's disease patients treated with selective MAO‐B inhibitor rasagiline
Authors: deMarcaida J. Antonelle , Schwid Steven R. , White William B. , Blindauer Karen , Fahn Stanley , Kieburtz Karl , Stern Matthew , Shoulson Ira 
Published: July 2006

AbstractRasagiline is a novel, potent, and selective MAO‐B inhibitor shown to be effective for Parkinson's disease. Traditional nonselective MAO inhibitors have been associated with dietary tyramine interactions that can induce hypertensive reactions. To test safety, tyramine challenges (50–75 mg) were performed in 72 rasagiline‐treated and 38 placebo‐treated Parkinson's disease (PD) patients at the end of two double‐blind placebo‐controlled trials of rasagiline. An abnormal pressor response was prespecified as three consecutive measurements of systolic blood pressure (BP) increases of ≥ 30 mm Hg and/or bradycardia of < 40 beats/min. In the first study involving 55 patients with early PD on rasagiline monotherapy, no patients randomized to rasagiline (1 mg/2 mg; n = 38) or placebo (n = 17) developed systolic BP (SBP) or heart rate changes indicative of a tyramine reaction. In the second trial involving 55 levodopa‐treated patients, 3 of 22 subjects on rasagiline 0.5 mg/day and 1 of 21 subjects on placebo developed asymptomatic, self‐limiting SBP elevations ≥ 30 mm Hg on three measurements. No subject on 1 mg/day rasagiline (0/12) experienced significant BP or heart rate changes following tyramine ingestion. These data demonstrate that rasagiline 0.5 to 2 mg daily is not associated with clinically significant tyramine reactions and can be used as monotherapy or adjunct to levodopa in PD patients without specific dietary tyramine restriction. © 2006 Movement Disorder Society
Elevated levels of amyloid precursor protein in muscle of patients with amyotrophic lateral sclerosis and a mouse model of the disease
Authors: Koistinen Hannu , Prinjha Rab , Soden Peter , Harper Alex , Banner Steven J. , Pradat Pierre‐François , Loeffler Jean‐Philippe , Dingwall Colin 
Published: July 2006

AbstractAmyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease defined by motor neuron loss. Transgenic mouse models show features that closely mimic those seen in the clinical situation, reflected in the molecular changes observed in mouse models and in tissues from patients. We report a dramatic increase in the expression of amyloid precursor protein (APP) in the hindlimb muscles, but not the spinal cord of the G93A transgenic mouse model, significantly before the appearance of clinical abnormalities. APP levels were unchanged in nontransgenic mice and in mice overexpressing human wild‐type Cu/Zn‐dependent superoxide dismutase 1 (SOD1). Preliminary results indicate a similar change in APP expression in human deltoid muscle samples from ALS patients compared with age‐matched controls. The inhibitory role of APP in innervation at the neuromuscular junction and increased expression in inclusion‐body myositis suggest that presymptomatic upregulation of APP may be consistent with a potential role for APP in ALS pathology. Muscle Nerve, 2006
Down‐regulation of p21 (CDKN1A/CIP1) is inversely associated with microsatellite instability and CpG island methylator phenotype (CIMP) in colorectal cancer
Authors: Ogino S , Kawasaki T , Kirkner GJ , Ogawa A , Dorfman I , Loda M , Fuchs CS 
Published: July 2006

Abstractp21 (CDKN1A/CIP1/WAF1), one of the cyclin‐dependent kinase inhibitors, plays a key role in regulating the cell cycle and is transcriptionally regulated by p53. Down‐regulation of p21 is caused by TP53 mutations in colorectal cancer. CpG island methylator phenotype (CIMP) appears to be a distinct subtype of colorectal cancer with concordant methylation of multiple gene promoters and is associated with a high degree of microsatellite instability (MSI‐H) and BRAF mutations. However, no study to date has evaluated the relationship between p21 expression and CIMP in colorectal cancer. The purpose of this study was to examine the inter‐relationships between p21, p53, CIMP, MSI and KRAS/BRAF status in colorectal cancer. We utilized 737 relatively unbiased samples of colorectal cancers from two large prospective cohort studies. Using quantitative real‐time PCR (MethyLight), we measured DNA methylation in five CIMP‐specific gene promoters [CACNA1G, CDKN2A (p16/INK4A), CRABP1, MLH1 and NEUROG1]. CIMP‐high (≥4/5 methylated promoters) was diagnosed in 118 (16%) of the 737 tumours. We also assessed expression of p21 and p53 by immunohistochemistry. Among the 737 tumours, 371 (50%) showed p21 loss. Both p21 loss and p53 positivity were inversely associated with CIMP‐high, MSI‐H and BRAF mutations. The associations of p21 with these molecular features were still present after tumours were stratified by p53 status. In contrast, the associations of p53 positivity with the molecular features were no longer present after tumours were stratified by p21 status. When CIMP‐high and non‐CIMP‐high tumours were stratified by MSI or KRAS/BRAF status, CIMP‐high and MSI‐H (but not BRAF mutations) were still inversely associated with p21 loss. In conclusion, down‐regulation of p21 is inversely correlated with CIMP‐high and MSI‐H in colorectal cancer, independent of TP53 and BRAF status. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Radiotherapy in the multimodal treatment of extrarenal extracranial malignant rhabdoid tumors
Authors: Puri Dev R. , Meyers Paul A. , Kraus Dennis H. , LaQuaglia Michael P. , Wexler Leonard H. , Wolden Suzanne L. 
Published: July 2006

AbstractExtrarenal extracranial malignant rhabdoid tumors (MRT) are extremely rare and typically lethal. No consensus exists on an optimal treatment approach, and, in particular, the role of radiation therapy (RT) is poorly defined. We report on three children who underwent multimodality treatment including surgery, chemotherapy (CMT), and RT. Two of these patients are alive and without evidence of disease 6½ and 7 years after diagnosis and one has expired. Our limited experience suggests that RT in the setting of CMT and surgery has the potential to prolong survival with acceptable toxicity, but outcomes are inconsistent and further study is necessary. Pediatr Blood Cancer 2008;50:167–169. © 2006 Wiley‐Liss, Inc.
Substitution of oral and intravenous thioguanine for mercaptopurine in a treatment regimen for children with standard risk acute lymphoblastic leukemia: A collaborative Children's Oncology Group/National Cancer Institute pilot trial (CCG‐1942)
Authors: Jacobs Shana S. , Stork Linda C. , Bostrom Bruce C. , Hutchinson Ray , Holcenberg John , Reaman Gregory H. , Erdmann Gary , Franklin Janet , Neglia Joseph P. , Steinberg Seth M. , Balis Frank M. , Adamson Peter C. 
Published: July 2006

AbstractBackgroundAlthough mercaptopurine (MP) is conventionally used to treat childhood acute lymphoblastic leukemia (ALL), thioguanine (TG) is a more potent thiopurine in vitro and, when administered orally to patients, achieves cytotoxic drug concentrations in the cerebrospinal fluid (CSF). We performed a pilot study incorporating oral and 24‐hr continuous IV infusion (CIVI) TG in children with newly diagnosed standard‐risk ALL.ProcedureChildren with newly diagnosed standard‐risk ALL (age 1–10 years, WBC < 50 k) were eligible. Multi‐agent chemotherapy was patterned after the Children's Cancer Group (CCG) 105 trial, with the addition of CIVI‐TG (480 mg/m2) during consolidation, interim maintenance and maintenance, and substitution of oral TG (60 mg/m2/day) for oral MP during maintenance.ResultsFifty‐eight patients (31 female), median age 4.3 years, were enrolled. At 8 years, the relapse‐free and overall survival probabilities were 83% and 88%. There were no CNS relapses. Six patients (five males) experienced reversible veno‐occlusive disease (VOD) while receiving oral TG, and the study was amended to discontinue TG, changing all patients to oral MP. Red cell TG nucleotide concentrations during oral TG averaged 95 ng (570 pmol)/8 × 108 RBC, greater than concentrations reported with oral MP.ConclusionAlthough the absence of CNS relapses in this pilot study suggests that TG may contribute to the prevention of CNS recurrences, the development of VOD negatively impacts the risk:benefit ratio of substituting TG for MP. Pediatr Blood Cancer 2007;49:250–255. © 2006 Wiley‐Liss, Inc.
Laboratory and field evaluations of rhodojaponin‐III against the imported cabbage worm Pieris rapae (L.) (Lepidoptera: Pieridae)
Authors: Zhong Guohua , Liu Jingxiang , Weng Qunfang , Hu Meiying , Luo Jianjun 
Published: July 2006

AbstractThe activity of rhodojaponin‐III (R‐III), a grayanoid diterpene compound isolated from Rhododendron molle G. Don flowers, was determined under laboratory and field conditions as an antifeedant, stomach poison, contact toxicant and insect growth inhibitor against Pieris rapae (L.) larvae. The median antifeedant concentration (AFC50) values in no‐choice leaf disc tests were 1.16 and 15.85 mg L−1 at 24 h after treatment when tested against third and fifth instars respectively. The median lethal concentration (LC50) values in leaf disc tests were 2.84 and 9.53 mg L−1 at 96 h after treatment against third and fifth instars respectively. R‐III showed an almost 30 times higher contact toxicity against third instars than for fifth instars, and the median lethal dose (LD50) values for topical application were 1.18 and 34.09 mg kg−1 at 72 h after treatment respectively. R‐III disrupted the development of larvae to pupae or adults with median concentration for inhibiting growth (IC50) values of only 1.36 mg L−1 for third instars and 11.28 mg L−1 for fifth instars. In field trials, a greater than 80% reduction in the adjusted larval numbers was obtained against P. rapae 14 days after treatment when Rhodo 0.1% EC, a commercial botanical insecticide based on R‐III, was applied at both 937.5 and 625 mL ha−1. These results suggest that further research to develop R‐III, and extracts from R. molle, as biorational pesticides or as lead compounds for integrated pest management deserve consideration. Copyright © 2006 Society of Chemical Industry
Theoretical investigation of the chain length effects on the NMR chemical shifts of oligomers
Authors: d'Antuono Philippe , Botek Edith , Champagne Benoît 
Published: July 2006

AbstractChain length effects on the 1H and 13C NMR chemical shifts have been theoretically investigated for increasingly large oligomers of isotactic and syndiotactic polypropylene and poly(vinyl chloride). Chains ranging from the dimer to the octamer and decamer have been considered for polypropylene and poly(vinyl chloride), respectively. Helical structures displaying successive TG backbone conformations represent the isotactic chains, whereas syndiotactic chains are considered to be all‐trans. The calculations are carried out by employing density functional theory (DFT) with the B3LYP exchange‐correlation functional and the 6‐311+G(2d,p) basis set. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
DFT study of bare and dye‐sensitized TiO2 clusters and nanocrystals
Authors: Lundqvist Maria J. , Nilsing Mattias , Persson Petter , Lunell Sten 
Published: July 2006

AbstractStructural and electronic properties of bare and dye‐sensitized TiO2 clusters and nanoparticles with sizes of ≤2 nm have been studied by density functional theory (DFT) calculations. Starting from truncated bulk lattice structures, the degree of structural reorganization, including the formation of TiO surface species, of bare TiO2 anatase nanocrystals, is found to be sensitive to the quality of the computational method. The electronic structures of optimized 1–2 nm nanoparticles show well‐developed band structures with essentially no electronic bandgap defect states. Significant bandgap broadening due to quantum size effects is observed as the size of the nanocrystals is reduced from 2 nm to 1 nm in diameter, but further bandgap widening is limited by increasingly severe competing surface defect sites as the particles become smaller than ∼1 nm in diameter. The applicability of the TiO2 nanocrystals in modeling the electronic structure and electronic coupling at dye‐sensitized TiO2 nanocrystal interfaces has been investigated by attachment of pyridine to one of the nanoparticle models via phosphonic or carboxylic acid anchor groups. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006
Hand‐assisted Laparoscopic Splenectomy and Devascularization of the Upper Stomach in the Management of Gastric Varices
Authors: Yamamoto Joji , Nagai Motoki , Smith Barry , Tamaki Satoshi , Kubota Tadao , Sasaki Ken , Ohmori Toshihiro , Maeda Kiyotaka 
Published: July 2006

AbstractBackgroundBleeding from esophagogastric varices is the major cause of death in patients with portal hypertension. Although esophageal varices can be treated with endoscopic procedures, the treatment for gastric varices is still controversial. The aim of this study was to describe a surgical technique and our preliminary results of hand‐assisted laparoscopic Hassab’s procedure.MethodsBetween February 2002 and May 2005, we performed 7 cases of gastric varices with this type of operation. The patients included 4 men and 3 women who ranged in age from 23 to 74 years (underlying liver disease: 5 case of liver cirrhosis, 1 case of polycystic disease, 1 case of extrahepatic portal vein obstruction). After splenctomy was performed, we devascularized the vessels of the upper stomach and the esophagus 5 cm away from the esophago‐cardia junction.ResultsThe operative time ranged from 132 to 290 minutes. Intraoperative blood loss was estimated to be from 50 ml to 475 ml. The weight of removed spleen ranged from 110 g to 800 g. During the follow‐up period, all gastric varices disappeared and no bleeding from varicose veins was observed. All patients had hypersplenism with thrombocytopenia before surgery (mean: 11.1 ± 7.4 × 104/ml), which was improved postoperatively (mean: 30.8 ±19.0 × 104/ml). This data were statistically significant (P = 0.033). One patient died of aspiration pneumonia related to postoperative pyloric stricture.ConclusionsAlthough there is no agreement concerning the best treatment of gastric varices, the hand‐assisted laparoscopic Hassab’s operation is a safe, moderately invasive method, and its outcome appears to be equal to that of other open procedures.
Experimental Comparison of Monofile Light and Heavy Polypropylene Meshes: Less Weight Does Not Mean Less Biological Response
Authors: Weyhe Dirk , Schmitz Inge , Belyaev Orlin , Grabs Robert , Müller Klaus‐Michael , Uhl Waldemar , Zumtobel Volker 
Published: July 2006

AbstractBackgroundMesh implantation is a standard procedure in hernia repair. It provides low recurrence rate but increases complication rate due to foreign‐body reaction induced by alloplastic materials in surrounding tissues. It is believed that biocompatibility of meshes may be improved by reducing their weight per meter squared (m2) and altering the implant structure.AimThe aim of this study was to evaluate the effect of weight and structure as determinants of mesh biocompatibility.MethodThirty‐six Wistar rats were studied. In 12 animals, conventional polypropylene (heavy) meshes (HM) were implanted; in other 12, material‐reduced (light) microporous polypropylene meshes (LM); and the remaining 12 served as a sham‐operated control group. Meshes were explanted after 21 and 90 days (6 animals per group). All samples were examined by light and electron microscopies. Integration of meshes in surrounding tissue, inflammatory response, fibrotic reactions, and structural changes were recorded. Quantification of the inflammatory response was achieved by CD‐68 marking of macrophages and counting their number per surface unit.ResultsAfter 21 days, there was no significant difference in thickness of surrounding connective tissue between meshes in all groups studied. After 90 days, thickness of connective tissue decreased in both groups, and fibrotic reaction in the mesh bed was significantly less in the HM group. Total amount of macrophages per millimeter squared (mm2) decreased with time in HM and LM samples but was significantly lower in the HM group on day 21 (43.5%) and day 90 (46.7%).ConclusionThis study found worse biocompatibility of LM compared with HM. Thus, the amount of implanted mesh was not the main determinant of biocompatibility (expressed as successful incorporation and diminished foreign‐body reaction) but the size of the pores.