bluuebunny/crossref_metadata_2025_split huggingface dataset:
Utilizing self‐prepared ELISA plates for a cross‐population study of different anti‐HBe IgG subclass profiles
Authors: Wang Lina , Tsai Tzu‐Hsin , Huang Chien‐Fu , Ho Mei‐Shang , Lin Ding‐Bang , Ho Yung‐Chyuan , Lin Shih‐Shen , Wei James Cheng‐Chung , Chou Ming‐Chih , Yang Chi‐Chiang 
Published: March 2007

AbstractFourteen serum samples obtained from hepatitis B virus (HBV) chronic carriers and patients recovered from hepatitis B infection were used with four sodium dodecyl sulfate‐treated enzyme‐linked immunosorbent assay (ELISA) plates available commercially, and one self‐prepared HBcAg analog for evaluation of anti‐HBe subclass pattern absorbance. The self‐prepared plates had the best performance and were thus used for samples obtained from 104 (60 male and 44 female) HBV chronic carriers and 439 (247 male and 192 female) recovered individuals. Tests for aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were also carried out in 21 of the subjects (>25 IU/ml). Statistical comparison of these patients with elevated ALT/AST levels with other ALT/AST‐normal chronic carriers revealed no significant differences in the anti‐HBe OD, although the mean optical density (OD) of patients with elevated ALT/AST levels was higher. The results suggest that the anti‐HBe IgG subclass profiles in the chronic carriers did not change with inflammation of the liver, and were independent of sex and age. In contrast to previous anti‐HBc findings, the distribution pattern of anti‐HBe subclasses in HBV chronic carriers was IgG1 > IgG4 > IgG3 while in the recovered individuals it was IgG1 > IgG3 > IgG4, for both males and females. Subclasses IgG1 and IgG2 were the most and least prevalent isotypes, respectively, in both study groups. The results of the study suggest that induction of IgG1 and/or IgG3 antibodies is important for effective virus neutralization, while IgG2 antibodies are of limited importance. Significantly higher OD values for anti‐HBe IgG4 were observed when comparing samples from the chronic carriers and recovered individuals, which may reflect the effects of persistence. Further, in contrast to previous anti‐HBs results, the concentrations of total IgG and IgG1 were higher in the samples from chronic carriers relative to those from recovered individuals. J. Med. Virol. 79:495–502, 2007. © 2007 Wiley‐Liss, Inc.
Cell specific internal translation efficiency of Epstein–Barr virus present in solid organ transplant patients
Authors: Isaksson Åsa , Berggren Malin , Ekeland‐Sjöberg Kerstin , Samuelsson Tore , Ricksten Anne 
Published: March 2007

AbstractThe U leader exon in the 5′ untranslated region of the Epstein–Barr virus nuclear antigen 1 (EBNA1) gene contains an internal ribosome entry site, the EBNA internal ribosome entry segment (IRES), which promotes cap‐independent translation and increases the expression level of the EBNA1 protein. It was previously reported that immunosuppressed organ transplanted patients showed an alternatively spliced EBNA1 transcript, excluding the EBNA IRES element. To further investigate the function of the EBNA IRES, sequence analysis of the EBNA IRES mRNA was performed in samples from seven organ transplant patients. Two nucleotide changes, G → A at position 67531 and C → U at position 67585 were found in the EBNA IRES mRNA, relative to the corresponding genomic Epstein–Barr virus (EBV) sequence in all patients. Moreover, the patient derived EBNA IRES mRNA was shown to differ from the IRES mRNA derived from the cell line B95.8 at position 67531 and from the cell lines Rael and P3HR1 at positions 67531 and 67585. cDNA from the various EBNA IRES sequences were cloned into bicistronic vectors, respectively, and used in transient transfection experiments in six human cell lines. The patient specific sequence significantly decreased the IRES activity in T‐cells, while the base changes had no significant impact on the activity in B‐ or in epithelial cells. The genetic mechanisms behind EBV‐associated diseases are complex, involving gene regulation by alternative promoters, alternative splicing, and translational control. The nucleotide changes in the patient specific EBNA IRES transcript and its influence on the translational activity, might illustrate new strategies utilised by the EBV to adapt to the immune control in patients with EBV associated diseases. J. Med. Virol. 79:573–581, 2007. © 2007 Wiley‐Liss, Inc.
Telomerase activity, hTERT expression, and phosphorylation are downregulated in CD4+T lymphocytes infected with human immunodeficiency virus type 1 (HIV‐1)
Authors: Franzese Ornella , Adamo Riccardo , Pollicita Michela , Comandini Alessandro , Laudisi Anastasia , Perno Carlo Federico , Aquaro Stefano , Bonmassar Enzo 
Published: March 2007

AbstractHuman immunodeficiency virus type 1 (HIV‐1) infection is characterized by a progressive decrease of CD4+T cells accompanied by other immune dysfunctions. Telomerase is transiently activated in lymphocytes during activation and is able to compensate for the progressive telomeric loss that occurs at each cell division, contributing to ensure the telomere length necessary for multiple proliferative events. The effect of HIV‐1 infection on telomerase activity and on the expression of some of the factors involved in its regulation in CD4+T cells was investigated. Telomerase was found to be downregulated in both nuclear and cytoplasmic compartments, together with an impairment of human telomerase reverse transcriptase (hTERT) expression and of the cell machinery involved in hTERT phosporylation. J. Med. Virol. 79:639–646, 2007. © 2007 Wiley‐Liss, Inc.
Human caliciviruses in symptomatic and asymptomatic infections in children in Vellore, South India
Authors: Monica Bindhu , Ramani Sasirekha , Banerjee Indrani , Primrose Beryl , Iturriza‐Gomara Miren , Gallimore Christopher I. , Brown David W. , M Fathima , Moses Prabhakar D. , Gray James J. , Kang Gagandeep 
Published: March 2007

AbstractPediatric gastroenteritis is a major cause of childhood morbidity and mortality worldwide, especially in developing countries. It has been increasingly recognised that human caliciviruses (HuCV), comprising noroviruses (NoV), and sapoviruses (SaV), are important in both outbreak and non‐outbreak settings. This study aimed to characterise caliciviruses detected in the faeces of hospitalized children and children in the community in India. This study examined 350 faecal samples from children presenting to the hospital with acute gastroenteritis and 673 samples collected from children in the community, 500 from children with diarrhea, and 173 samples from children without diarrhea. Strain characterisation was performed by reverse transcription‐polymerase chain reaction (RT‐PCR) and partial sequencing of the gene encoding the RNA‐dependent RNA polymerase (RdRp) and/or a region spanning the open reading frames (ORFs) 1 and 2 (ORF1/ORF2) junction. A total of 68 of 350 specimens (19.4%) from hospitalized children were positive, and SaV and NoV accounted for 5.1 and 15.1% of the infections, respectively. Mixed infections of HuCVs with other enteric pathogens were seen in 9.4% of the total children tested. Sixty‐eight out of 673 (10.1%) samples collected from children in the community were positive for caliciviruses, and SaV and NoV accounted for 3.4 and 6.6% of the infections. In the community cohort 55/500 (11%) and 13/173 (7.5%) were from symptomatic and asymptomatic children, respectively, and SaVs accounted for 17/500 (3.4%) and NoVs for 38/500 (7.6%) of the symptomatic infections. This is the first report of genotyping of circulating caliciviruses in both hospital and community in India and has increased the evidence for the role of these viruses in pediatric gastroenteritis in India. J. Med. Virol. 79:544–551, 2007. © 2007 Wiley‐Liss, Inc.
Insulin and insulin‐like growth factor type‐I up‐regulate the vanilloid receptor‐1 (TRPV1) in stably TRPV1‐expressing SH‐SY5Y neuroblastoma cells
Authors: Lilja Johanna , Laulund Frida , Forsby Anna 
Published: March 2007

AbstractThe capsaicin receptor, transient receptor potential, vanilloid type 1 (TRPV1), is a Ca2+‐permeable ion channel activated by noxious stimuli eliciting pain. Several reports have shown modulation of TRPV1 activity and expression by neuronal growth factors. Here, we study the long‐term effects on TRPV1 expression mediated by insulin‐like growth factor type‐I (IGF‐I) and insulin in a stably TRPV1‐expressing SH‐SY5Y neuroblastoma cell line. We show that, after 72 hr of 10 nM IGF‐I or insulin exposure, the TRPV1 protein level was up‐regulated 2.5‐ and 2‐fold, respectively. By blocking phosphatidylinositol‐3‐kinase [PI(3)K] or mitogen‐activated protein kinase (MAPK) signaling, we concluded that the increase in total TRPV1 protein content induced by IGF‐I was controlled by PI(3)K signaling, whereas insulin seemed to regulate TRPV1 protein expression via both PI(3)K and MAPK pathways. Inhibiting protein kinase C (PKC) blocked the effects of both IGF‐I and insulin. Furthermore, the concentrations causing a 50% Ca2+ increase (EC50) after insulin and IGF‐I treatments were significantly lowered compared with untreated cells. We conclude that IGF‐I and insulin enhance TRPV1 protein expression and activity, and impaired pain sensation might result from distorted TRPV1 regulation in the peripheral nervous system. © 2007 Wiley‐Liss, Inc.
BH3‐only proteins Bid and BimEL are differentially involved in neuronal dysfunction in mouse models of Huntington's disease
Authors: García‐Martínez Juan M. , Pérez‐Navarro Esther , Xifró Xavier , Canals Josep M. , Díaz‐Hernández Miguel , Trioulier Yael , Brouillet Emmanuel , Lucas José J. , Alberch Jordi 
Published: March 2007

AbstractApoptosis, a cell death mechanism regulated by Bcl‐2 family members, has been proposed as one of the mechanisms leading to neuronal loss in Huntington's disease (HD). Here we examined the regulation of Bcl‐2 family proteins in three different mouse models of HD with exon 1 mutant huntingtin: the R6/1, the R6/1:BDNF+/−, and the Tet/HD94 in which the huntingtin transgene is controlled by the tetracycline‐inducible system. Our results disclosed an increase in the levels of the BH3‐only proteins Bid and BimEL in the striatum of HD mouse models that was different depending on the stage of the disease. At 16 weeks of age, Bid was similarly enhanced in the striatum of R6/1 and R6/1:BDNF+/− mice, whereas BimEL protein levels were enhanced only in R6/1:BDNF+/− mice. In contrast, at later stages of the disease, both genotypes displayed increased levels of Bid and BimEL proteins. Furthermore, Bax, Bak, Bad, Bcl‐2, and Bcl‐xL proteins were not modified in any of the points analyzed. We next explored the potential reversibility of this phenomenon by analyzing conditional Tet/HD94 mice. Constitutive expression of the transgene resulted in increased levels of Bid and BimEL proteins, and only the Bid protein returned to wild‐type levels 5 months after mutant huntingtin shutdown. In conclusion, our results show that enhanced Bid protein levels represent an early mechanism linked to the continuous expression of mutant huntingtin that, together with enhanced BimEL, may be a reporter of the progress and severity of neuronal dysfunction. © 2007 Wiley‐Liss, Inc.
Serum albumin improves recovery from spinal cord injury
Authors: Cain Lisa D. , Nie Linghui , Hughes Michael G. , Johnson Kathia , Echetebu Clement , Xu Guo‐Ying , Hulsebosch Claire E. , McAdoo David J. 
Published: March 2007

AbstractA neuroprotective factor is shown to be present in mammalian serum. This factor is identified by Western blotting to be serum albumin. The serum factor and albumin both protected cultured spinal cord neurons against the toxicity of glutamate. The inability of K252a, a blocker of the high affinity tyrosine kinase receptor for members of the nerve growth factor family, to block the neuroprotective effect of the serum factor established that the serum factor is not a member of the nerve growth factor family. Post‐injury injection of albumin intravenously or into the site of injury immediately after injury both improved significantly locomotor function according to Basso‐Beattie‐Bresnahan assessment and spontaneous locomotor activity recorded with a photobeam activity system. Albumin has multiple mechanisms whereby it may be neuroprotective, and it is a potentially useful agent for treating neurotraumas. © 2007 Wiley‐Liss, Inc.
An increase in S‐glutathionylated proteins in the Alzheimer's disease inferior parietal lobule, a proteomics approach
Authors: Newman Shelley F. , Sultana Rukhsana , Perluigi Marzia , Coccia Rafella , Cai Jian , Pierce William M. , Klein Jon B. , Turner Delano M. , Butterfield D. Allan 
Published: March 2007

AbstractAlzheimer's disease (AD) is a neurodegenerative disorder characterized by neurofibrillary tangles, senile plaques, and loss of synapses. Many studies support the notion that oxidative stress plays an important role in AD pathogenesis. Previous studies from our laboratory employed redox proteomics to identify oxidatively modified proteins in the AD inferior parietal lobule (IPL) and hippocampus. The proteins were consistent with biochemical or pathological alterations in AD and have been central to further investigations of the disease. The present study focused on the identification of specific targets of protein S‐glutathionylation in AD and control IPL by using a redox proteomics approach. For AD IPL, we identified deoxyhemoglobin, α‐crystallin B, glyceraldehyde phosphate dehydrogenase (GAPDH), and α‐enolase as significantly S‐glutathionylated relative to these brain proteins in control IPL. GAPDH and α‐enolase were also shown to have reduced activity in the AD IPL. This study demonstrates that specific proteins are sensitive to S‐glutathionylation, which most likely is due to their sensitivity to cysteine oxidation initiated by the increase in oxidative stress in the AD brain. © 2007 Wiley‐Liss, Inc.
Late Quaternary river development in the southwest Chad Basin: OSL dating of sediment from the Komadugu palaeofloodplain (northeast Nigeria)
Authors: Gumnior Maren , Preusser Frank 
Published: March 2007

AbstractThe Komadugu river system is the major Nigerian tributary to Lake Chad. Its large alluvial complex represents an important archive of the late Quaternary environmental history of the Chad Basin. Modern floodplains are incised into an older fluvial terrace that extends over 5000 km2. Evidence from satellite images suggests that the ancient river system was dammed up by the Bama Beach Ridge during high stands of mega Lake Chad. This caused the formation of extensive wetlands with a chaotic network of relic channels. The first set of luminescence ages presented here fits well into the previously established environmental history of the Chad Basin. Both the early and mid‐Holocene pluvial periods as well as a final relatively humid period during the late Holocene are reflected by point bar to overbank deposits or channel fills. The onset of the Holocene was characterised by erosion of older dune fields as indicated by grain‐size distributions of the alluvium. Satellite images and sedimentological observations show that the floodplain was dominated by meandering channels shifted by frequent avulsion, reflecting a high variability in precipitation and discharge patterns at the beginning and end of Holocene humid periods. Copyright © 2007 John Wiley & Sons, Ltd.
Conduction and excitability properties of peripheral nerves in end‐stage liver disease
Authors: Ng Karl , Lin Cindy S.‐Y. , Murray Nicholas M.F. , Burroughs Andrew K. , Bostock Hugh 
Published: March 2007

AbstractThe pathophysiology of hepatic neuropathy is poorly understood, but membrane depolarization due to a toxic inhibition of oxidative metabolism has been proposed. We investigated the relationship between nerve excitability properties, nerve dysfunction, and liver function in 11 pretransplant patients, the majority of whom were oligo‐ or asymptomatic for peripheral neuropathy. Abnormalities were detected on clinical examination (6), large‐fiber nerve conduction (4), and thermal quantitative sensory testing (10). Small‐fiber involvement was characterized by elevation of warm more than cold detection thresholds. Autonomic dysfunction was less frequent (4). Nerve excitability parameters in both upper and lower limbs provided evidence of membrane depolarization compared with controls, even in those patients without a history of alcohol abuse. No clear correlation was found between neurophysiological indices and scores of hepatic reserve or various blood parameters including ammonia level. Although chronic membrane depolarization may be involved, the degree of depolarization in large fibers was small, and its role in the pathophysiology of neuropathy uncertain. Muscle Nerve, 2007
Formation and characterization of polymersomes made by a solvent injection method
Authors: Yildiz M. E. , Prud'homme R. K. , Robb I. , Adamson D. H. 
Published: March 2007

AbstractIn this article a solvent injection method is described for vesicle formation using poly(butadiene)‐ b‐poly(acrylic acid) diblock copolymers as the amphiphilic molecules. Vesicles composed of polymer bilayers are commonly referred to as polymersomes. Solvent injection is shown to be a rapid method for polymersome formation suitable to make large volumes of polymersome solution. The method can be manipulated to obtain a wide range of vesicle sizes depending on the polymer concentration and preparation conditions. Polymersome solutions in this study are characterized using dynamic light scattering (DLS), fluorescent microscopy, and electron microscopy. Polymersome sizes range from tens of nanometers to several microns. The membrane thickness of smaller polymersomes is found to lie between 14–20 nm. Larger polymersomes are found to have somewhat thicker membranes. The procedure involves the addition of polymers dissolved in an organic solvent to a stirred aqueous solution. The formation of polymersomes by this method is proposed to be governed by the limited mutual solubility of the two solvents and the simultaneous diffusion of solvent and water out of and in to initially formed organic solvent droplets. Copyright © 2007 John Wiley & Sons, Ltd.
Effect of the separation of Coulomb centers on the activation energy in electronic hopping transport: A reinterpretation in poly‐N‐vinylcarbazole
Authors: Santos S. , Caraballo D. 
Published: March 2007

AbstractThe effect of the separation of Coulomb centers in the activation energy for the electronic hopping transport of noncrystalline organic materials was studied. The theoretical analysis was carried out in absence of an applied electric field, using a simple one‐dimensional model of two centers separated by a distance R. It was found that the height of the potential well is reduced by an amount e2/4πεε0R due to the overlapping of the Coulomb centers. This reduction defines an effective activation energy given by (ΔE)0 − e2/4πεε0R, where (ΔE)0 is the height of the nonperturbed potential well. As an experimental application of this result, current–voltage characteristic in poly‐N‐vinylcarbazole at different temperatures was obtained, from which the conductivity at zero electric field was estimated by extrapolation to zero field in Poole‐Frenkel plots. The correspondent activation energy was estimated from Arrhenius plots in the order of 0.65 eV. Because the carriers transport in this polymer occurs by hopping between the molecules of carbazole whose mean separation is in the order of 6.5 × 10−10 m, the height of the nonperturbed Coulomb barrier of a single hopping site in this material would be really estimated in 1.18 eV. POLYM. ENG. SCI., 47:545–550, 2007. © 2007 Society of Plastics Engineers.
Modeling the vulcanization reaction of silicone rubber
Authors: Lopez L.M. , Cosgrove A.B. , Hernandez‐Ortiz J.P. , Osswald T.A. 
Published: March 2007

AbstractCharacterization of the vulcanization process of silicone rubber was achieved through the modeling of dynamic DSC tests. The Kissinger equation and the Kamal‐Sourour model were used to determine kinetic parameters that fit the experimental data. The technique allows for the determination of the activation energy through Kissinger's model, which is then used to mathematically determine the other five parameters for the Kamal‐Sourour model. This novel technique finds a physically meaningful activation energy. The method generates a single set of parameters that accurately models all scanning rates tested (1, 2.5, 5, and 10 K/min). Five formulations of liquid silicone rubber as well as one solid silicone rubber were tested and modeled. For each material, the models generated fitting parameters that were in agreement with the dynamic DSC scans. The models were used to compare the processing of the liquid and solid silicone rubber. The characterization of both materials demonstrates the lower processing time, temperatures, and energy consumption when processing liquid silicone rubber, as compared to processing of hard silicone rubber. POLYM. ENG. SCI., 47:675–683, 2007. © 2007 Society of Plastics Engineers.
Rubber‐toughened polypropylene/acrylonitrile‐co‐butadiene‐co‐styrene blends: Morphology and mechanical properties
Authors: Šlouf Miroslav , Kolařík Jan , Kotek Jiří 
Published: March 2007

AbstractThe RTPP/ABS (rubber toughened polypropylene/poly (acrylonitrile‐co‐butadiene‐co‐styrene) blends, both noncompatibilized and compatibilized with polypropylene‐g‐polystyrene, were prepared by melt mixing in a Brabender Plasti‐Corder. As the torque ratio of RTPP and ABS was about 2, phase cocontinuity in the blends was achieved at ABS volume fractions around 0.16, which was evidenced by both microscopic analysis and mechanical testing. A new microscopic and image analysis technique was introduced, whose combination provides two semiquantitative parameters: structure roughness and structure cocontinuity. The latter parameter is closely associated with the predictive scheme based on the equivalent box model and percolation theory, which was used in this study. The predicted mechanical properties were confronted with the experimental data for tensile modulus, yield strength, and tensile impact strength. While the modulus of noncompatibilized blends is reasonably fitted by the model, the compatibilizer accounts for a positive deviation attributed to a strong interaction between the compatibilizer and the matrix. The yield strength of noncompatibilized blends indicates poor interfacial adhesion, which is so enhanced by the compatibilizer that no phase debonding occurs before yielding. Tensile impact strength, in contrast to modulus and yield strength, passes through a deep minimum for both types of blends; two tentative explanations of this detrimental behavior were suggested. POLYM. ENG. SCI., 47:582–592, 2007. © 2007 Society of Plastics Engineers.