bluuebunny/crossref_metadata_2025 huggingface dataset:
Signal transducer and activator of transcription 3 signaling within hepatocytes attenuates systemic inflammatory response and lethality in septic mice
Authors: Sakamori Ryotaro , Takehara Tetsuo , Ohnishi Chihiro , Tatsumi Tomohide , Ohkawa Kazuyoshi , Takeda Kiyoshi , Akira Shizuo , Hayashi Norio
Published: August 2007

Sepsis is an infection-induced syndrome with systemic inflammatory response leading to multiorgan failure and occasionally death. During this process, signal transducer and activator of transcription 3 (STAT3) is activated in the liver, but the significance of this molecule has not been established. We generated hepatocyte-specific STAT3-deficient mice (L-STAT3 KO) and examined the susceptibility of these mice to cecal ligation and puncture–induced peritonitis, a well-established septic model. L-STAT3 KO mice showed significantly higher mortality and produced lesser amounts of various acute phase proteins than control littermates. Although blood bacterial infection did not differ between L-STAT3 KO mice and control mice, the former showed deterioration of the systemic inflammatory response as evidenced by a significant increase in various cytokines such as tumor necrosis factor α, IFN-γ, IL-6, IL-10, monocyte chemoattractant protein 1, and macrophage inflammatory protein 1β. A similar hyperinflammatory response was observed in another septic model caused by lipopolysaccharide (LPS) injection. In vitro analysis revealed that soluble substances derived from hepatocytes and dependent on STAT3 were critical for suppression of cytokine production from LPS-stimulated macrophage and splenocytes.

Conclusion:

STAT3 activation in hepatocytes can attenuate a systemic hyperinflammatory response and lethality in sepsis, in part by suppressing immune cell overactivation, implying a critical role of hepatocyte STAT3 signaling in maintaining host homeostasis.
Increased hepatotoxicity of tumor necrosis factor–related apoptosis-inducing ligand in diseased human liver
Authors: Volkmann Xandra , Fischer Ute , Bahr Matthias J. , Ott Michael , Lehner Frank , MacFarlane Marion , Cohen Gerald M. , Manns Michael P. , Schulze-Osthoff Klaus , Bantel Heike
Published: August 2007

Tumor necrosis factor–related apoptosis-inducing ligand (TRAIL) induces apoptosis in tumor cells but not in most normal cells and has therefore been proposed as a promising antitumor agent. Recent experiments suggested that isolated primary human hepatocytes but not monkey liver cells are susceptible to certain TRAIL agonists, raising concerns about the use of TRAIL in cancer treatment. Whether TRAIL indeed exerts hepatotoxicityin vivoand how this is influenced by chemotherapeutic drugs or liver disease are completely unknown. Employing different forms of recombinant TRAIL, we found that the cytokine can induce proapoptotic caspase activity in isolated human hepatocytes. However in marked contrast, these different TRAIL preparations induced little or no cytotoxicity when incubated with tissue explants of fresh healthy liver, an experimental model that may more faithfully mimic thein vivosituation. In healthy liver, TRAIL induced apoptosis only when combined with histone deacetylase inhibitors. Strikingly, however, TRAIL alone triggered massive apoptosis accompanied by caspase activation in tissue explants from patients with liver steatosis or hepatitis C viral infection. This enhanced sensitivity of diseased liver was associated with an increased expression of TRAIL receptors and up-regulation of proapoptotic Bcl-2 proteins.

Conclusion:

These results suggest that clinical trials should be performed with great caution when TRAIL is combined with chemotherapy or administered to patients with inflammatory liver diseases.
Apoptotic hepatocyte DNA inhibits hepatic stellate cell chemotaxis via toll-like receptor 9
Authors: Watanabe Azuma , Hashmi Ardeshir , Gomes Dawidson Assis , Town Terrence , Badou Abdallah , Flavell Richard Anthony , Mehal Wajahat Zafar
Published: August 2007

Apoptosis of hepatocytes results in the development of liver fibrosis, but the molecular signals mediating this are poorly understood. Degradation and modification of nuclear DNA is a central feature of apoptosis, and DNA from apoptotic mammalian cells is known to activate immune cells via Toll-like receptor 9 (TLR9). We tested if DNA from apoptotic hepatocytes can induce hepatic stellate cell (HSC) differentiation. Our data show that apoptotic hepatocyte DNA and cytidine-phosphate-guanosine oligonucleotides induced up-regulation of transforming growth factor β1 and collagen 1 messenger RNA both in the human HSC line LX-2 and in primary mouse HSCs. These effects were opposed by TLR9 antagonists. We have recently shown that adenosine inhibits HSC chemotaxis, and we now show that apoptotic hepatocyte DNA also inhibits platelet-derived growth factor (PDGF)-mediated HSC chemotaxis. Inhibition of HSC chemotaxis by PDGF was blocked by TLR9 antagonists, and was absent in primary HSCs from mice deficient in TLR9 or the TLR adaptor molecule MyD88. Stimulation of TLR9 on HSCs blocked signaling by the PDGF signaling molecule inositol 1,4,5-triphosphate and reduced PDGF-mediated increase in cytosolic Ca2+.

Conclusion:

DNA from apoptotic hepatocytes acts as an important mediator of HSC differentiation by (1) providing a stop signal to mobile HSCs when they have reached an area of apoptosing hepatocytes and (2) inducing a stationary phenotype-associated up-regulation of collagen production.
Efficient generation of human hepatocytes by the intrahepatic delivery of clonal human mesenchymal stem cells in fetal sheep
Authors: Chamberlain Jason , Yamagami Takashi , Colletti Evan , Theise Neil D. , Desai Jyoti , Frias Ana , Pixley John , Zanjani Esmail D. , Porada Christopher D. , Almeida-Porada Graça
Published: August 2007

Alternative methods to whole liver transplantation require a suitable cell that can be expanded to obtain sufficient numbers required for successful transplantation while maintaining the ability to differentiate into hepatocytes. Mesenchymal stem cells (MSCs) possess several advantageous characteristics for cell-based therapy and have been shown to be able to differentiate into hepatocytes. Thus, we investigated whether the intrahepatic delivery of human MSCs is a safe and effective method for generating human hepatocytes and whether the route of administration influences the levels of donor-derived hepatocytes and their pattern of distribution throughout the parenchyma of the recipient's liver. Human clonally derived MSCs were transplanted by an intraperitoneal (n = 6) or intrahepatic (n = 6) route into preimmune fetal sheep. The animals were analyzed 56–70 days after transplantation by immunohistochemistry, enzyme-linked immunosorbent assay, and flow cytometry. The intrahepatic injection of human MSCs was safe and resulted in more efficient generation of hepatocytes (12.5% ± 3.5% versus 2.6% ± 0.4%). The animals that received an intrahepatic injection exhibited a widespread distribution of hepatocytes throughout the liver parenchyma, whereas an intraperitoneal injection resulted in a preferential periportal distribution of human hepatocytes that produced higher amounts of albumin. Furthermore, hepatocytes were generated from MSCs without the need to first migrate/lodge to the bone marrow and give rise to hematopoietic cells.

Conclusion:

Our studies provide evidence that MSCs are a valuable source of cells for liver repair and regeneration and that, by the alteration of the site of injection, the generation of hepatocytes occurs in different hepatic zones, suggesting that a combined transplantation approach may be necessary to successfully repopulate the liver with these cells. (Hepatology 2007.)
Determinants of skin sensitisation potential
Authors: Roberts David W. , Aptula Aynur O.
Published: August 2007

Skin sensitisation is an important toxicological endpoint. The possibility that chemicals used in the workplace and in consumer products might cause skin sensitisation is a major concern for individuals, for employers and for marketing. In European REACH (Registration, Evaluation, and Authorisation of Chemicals) legislation, the sensitising potential should therefore be assessed for chemicals below the 10 ton threshold. Development of methods for prediction of skin sensitisation potential without animal testing has been an active research area for some time, but has received further impetus with the advent of REACH and the EU Cosmetics Directive (EU 2003). This paper addresses the issue of non‐animal based prediction of sensitisation by a mechanistic approach. It is known that the sequence of molecular, biomolecular and cellular events between exposure to a skin sensitiser and development of the sensitised state involves several stages, in particular penetration through the stratum corneum, covalent binding to carrier protein, migration of Langerhans cells, presentation of the antigen to naïve T‐cells. In this paper each of these stages is considered with respect to the extent to which it is dependent on the chemical properties of the sensitiser. The evidence suggests that, although penetration of the stratum corneum, stimulation of migration and maturation of Langerhans cells, and antigen recognition are important events in the induction of sensitisation, except in certain specific circumstances they can be taken for granted. They are not important factors in determining whether a compound will be a sensitiser or not, nor are they important factors in determining how potent one sensitiser will be relative to another. The ability to bind covalently to carrier protein is the major structure‐dependent determinant of skin sensitisation potential. A chemistry‐based prediction strategy is proposed involving reaction mechanistic domain assignment, reactivity and hydrophobicity determination, and application of quantitative mechanistic modelling (QMM) or read‐across. Copyright © 2007 John Wiley & Sons, Ltd.
Chemical reactivity indices and mechanism‐based read‐across for non‐animal based assessment of skin sensitisation potential
Authors: Roberts David W. , Aptula Aynur O. , Patlewicz Grace , Pease Camilla
Published: August 2007

The skin sensitisation potential of chemicals is currently assessed using in vivo methods where the murine local lymph node assay (LLNA) is typically the method of first choice. Current regulatory initiatives are driving the impetus for the use of in vitro/in silico alternative approaches to provide the relevant information needed for the effective assessment of skin sensitisation, for both hazard characterisation and risk assessment purposes. A chemical must undergo a number of steps for it to induce skin sensitisation but the main determining step is formation of a stable covalent association with carrier protein. The ability of a chemical to react covalently with carrier protein nucleophiles relates to both its electrophilic reactivity and its hydrophobicity.

This paper focuses on quantitative indices of electrophilic reactivity with nucleophiles, in a chemical mechanism‐of‐action context, and compares and contrasts the experimental approaches available to generate reactivity data that are suitable for mathematical modelling and making predictions of skin sensitisation potential, using new chemistry data correlated against existing in vivo bioassay data. As such, the paper goes on to describe an illustrative example of how quantitative kinetic measures of reactivity can be usefully and simply applied to perform mechanism‐based read‐across that enables hazard characterisation of skin sensitisation potential. An illustration of the types of quantitative mechanistic models that could be built using databases of kinetic measures of reactivity, hydrophobicity and existing in vivo bioassay data is also given. Copyright © 2007 John Wiley & Sons, Ltd.
Computational chemistry approach for the early detection of drug‐induced idiosyncratic liver toxicity
Authors: Cruz‐Monteagudo Maykel , Cordeiro M. Natália D. S. , Borges Fernanda
Published: August 2007

Idiosyncratic drug toxicity (IDT), considered as a toxic host‐dependent event, with an apparent lack of dose response relationship, is usually not predictable from early phases of clinical trials, representing a particularly confounding complication in drug development. Albeit a rare event (usually <1/5000), IDT is often life threatening and is one of the major reasons new drugs never reach the market or are withdrawn post marketing. Computational methodologies, like the computer‐based approach proposed in the present study, can play an important role in addressing IDT in early drug discovery. We report for the first time a systematic evaluation of classification models to predict idiosyncratic hepatotoxicity based on linear discriminant analysis (LDA), artificial neural networks (ANN), and machine learning algorithms (OneR) in conjunction with a 3D molecular structure representation and feature selection methods. These modeling techniques (LDA, feature selection to prevent over‐fitting and multicollinearity, ANN to capture nonlinear relationships in the data, as well as the simple OneR classifier) were found to produce QSTR models with satisfactory internal cross‐validation statistics and predictivity on an external subset of chemicals. More specifically, the models reached values of accuracy/sensitivity/specificity over 84%/78%/90%, respectively in the training series along with predictivity values ranging from ca. 78 to 86% of correctly classified drugs. An LDA‐based desirability analysis was carried out in order to select the levels of the predictor variables needed to trigger the more desirable drug, i.e. the drug with lower potential for idiosyncratic hepatotoxicity. Finally, two external test sets were used to evaluate the ability of the models in discriminating toxic from nontoxic structurally and pharmacologically related drugs and the ability of the best model (LDA) in detecting potential idiosyncratic hepatotoxic drugs, respectively. The computational approach proposed here can be considered as a useful tool in early IDT prognosis. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008
Primitive versus derived traits in the developmental program of the vertebrate head: views from cyclostome developmental studies
Authors: Kuratani Shigeru , Ota Kinya G.
Published: August 2007

Evolution can be viewed as a series of changes in the developmental program along the phylogenetic tree. To better understand the early evolution of the vertebrate skull, we can use the embryos of the cyclostome species as models. By comparing the cyclostome developmental patterns with those of gnathostomes, it becomes possible to distinguish the primitive and derived parts of the developmental program as taxon‐specific traits. These traits are often recognizable as developmental constraints that define taxa by biasing the developmental trajectories within a certain limited range, resulting in morphological homologies in adults. These developmental constraints are distributed on the phylogenetic tree like the morphological character states of adult animals and are associated with specific regions of the tree. From this perspective, we emphasize the importance of considering gene expression and embryonic anatomy as the mechanistic bases that can result in homologous or nonhomologous morphological patterns at later developmental stages. Taking the acquisition of the jaw and trabecula cranii as examples, we demonstrate that a set of embryonic features can be coupled or decoupled during evolution and development. When they are coupled, they exert an ancestral developmental constraint that results in homologous morphological patterns, and when they are decoupled, the ancestral constraints tend to be abandoned, generating a new body plan. The heterotopy behind the specification of the oral domain is an example of decoupling, based on shifted tissue interactions. We also stress the importance of “developmental burden” in determining the sequential order of changes through evolution.J. Exp. Zool. (Mol. Dev. Evol.) 310B:294–314, 2008. © 2007 Wiley‐Liss, Inc.
Management of blood pressure after acute ischemic stroke: An evidence‐based guide for the hospitalist
Authors: Cumbler Ethan , Glasheen Jeffrey
Published: August 2007

Hospitalists are frequently called upon to manage blood pressure after acute ischemic stroke. A review of both post infarction cerebral perfusion physiology and the data from randomized trials of antihypertensive therapy is necessary to explain why consensus guidelines for blood pressure management after stroke differ from those of other hypertensive emergencies. The peri‐infarct penumbra is the central concept in understanding post ischemic cerebral perfusion. This area of impaired cerebral blood flow is dependent on mean arterial blood pressure and acute reduction of blood pressure may expand the area of infarction. Review of clinical trials fails to show benefit from reduction of blood pressure after ischemic stroke and current guidelines suggest antihypertensive therapy be employed if the systemic blood pressure is greater than 180/105 mmHg after tPA is employed, or 220/120 mmHg when tPA is not used. Induced hypertension remains a promising but unproven therapy in the acute setting, but the evidence for long term control of blood pressure to less than 140/80 mmHG for secondary prevention of stroke is strong. Adherence to guidelines is poor but it is recognized that current evidence is limited by a lack of trials in which blood pressure is titrated to a pre‐specified goal, as is common in clinical practice. Journal of Hospital Medicine 2007;2:261–267. © 2007 Society of Hospital Medicine.
Temperature‐dependent localization of GPI‐anchored intestinal alkaline phosphatase in model rafts
Authors: Giocondi Marie‐Cécile , Besson Françoise , Dosset Patrice , Milhiet Pierre‐Emmanuel , Le Grimellec Christian
Published: August 2007

In plasma membranes, most of glycosylphosphatidylinositol (GPI)‐anchored proteins would be associated with rafts, a category of ordered microdomains enriched in sphingolipids and cholesterol (Ch). They would be also concentrated in the detergent resistant membranes (DRMs), a plasma membrane fraction extracted at low temperature. Preferential localization of GPI‐anchored proteins in these membrane domains is essentially governed by their high lipid order, as compared to their environment. Changes in the temperature are expected to modify the membrane lipid order, suggesting that they could affect the distribution of GPI‐anchored proteins between membrane domains. Validity of this hypothesis was examined by investigating the temperature‐dependent localization of the GPI‐anchored bovine intestinal alkaline phophatase (BIAP) into model raft made of palmitoyloleoylphosphatidylcholine/sphingomyelin/cholesterol (POPC/SM/Chl) supported membranes. Atomic force microscopy (AFM) shows that the inserted BIAP is localized in the SM/Chl enriched ordered domains at low temperature. Above 30°C, BIAP redistributes and is present in both the ‘fluid’ POPC enriched and the ordered SM/Chl domains. These data strongly suggest that in cells the composition of plasma membrane domains at low temperature differs from that at physiological temperature. Copyright © 2007 John Wiley & Sons, Ltd.
Docking study and free energy simulation of the complex between p53 DNA‐binding domain and azurin
Authors: De Grandis Valentina , Bizzarri Anna Rita , Cannistraro Salvatore
Published: August 2007

Molecular interaction between p53 tumor suppressor and the copper protein azurin (AZ) has been demonstrated to enhance p53 stability and hence antitumoral function, opening new perspectives in cancer treatment. While some experimental work has provided evidence for AZ binding to p53, no crystal structure for the p53–AZ complex was solved thus far. In this work the association between AZ and the p53 DNA‐binding domain (DBD) was investigated by computational methods. Using a combination of rigid‐body protein docking, experimental mutagenesis information, and cluster analysis 10 main p53 DBD–AZ binding modes were generated. The resulting structures were further characterized by molecular dynamics (MD) simulations and free energy calculations. We found that the highest scored docking conformation for the p53 DBD–AZ complex also yielded the most favorable free energy value. This best three‐dimensional model for the complex was validated by using a computational mutagenesis strategy. In this structure AZ binds to the flexible L1 and s7–s8 loops of the p53 DBD and stabilizes them through protein–protein tight packing interactions, resulting in high degree of both surface matching and electrostatic complementarity. Copyright © 2007 John Wiley & Sons, Ltd.
Interferon‐induced prolonged biochemical response reduces hepatocarcinogenesis in hepatitis C virus infection
Authors: Arase Yasuji , Ikeda Kenji , Suzuki Fumitaka , Suzuki Yoshiyuki , Kobayashi Masahiro , Akuta Norio , Hosaka Tetsuya , Sezaki Hitomi , Yatsuji Hiromi , Kawamura Yusuke , Kobayashi Mariko , Kumada Hiromitsu
Published: August 2007

The aim of this study was to elucidate indicator of interferon (IFN) therapy for reducing hepatocellular carcinoma (HCC) in chronic hepatitis C patients without eradicating hepatitis C virus (HCV) RNA during IFN therapy. Inclusion criteria were biopsy‐proven chronic hepatitis or liver cirrhosis, IFN period for more than 1.5 years and persistently positive HCV‐RNA during IFN therapy. Two hundred thirty‐six patients satisfied above criteria were treated with IFN for 1.5–5 years (median 1.8 years, mean 2 years). Mean age was 55.1 years and male was 145(61%). Eighty‐one (34%) patients had severe fibrosis of the liver. These patients were prospectively monitored about HCC after the termination of IFN therapy. We regarded biochemical response (BR) as normalization of serum aminotransferase and alpha‐fetoprotein for more than 1 year during IFN therapy. Cumulative rate of development of HCC after the termination of IFN therapy was 9.1% at 5th year and 26.5% at 10th year. Cox proportional analysis showed that HCC development after the termination of IFN therapy occurred when histological staging was advanced (P < 0.0001) and BR was not achieved (P = 0.009), age was >60 years (P = 0.026). The relative risk of HCC development in patients with BR was 0.36 compared with patients without BR. The attainment of BR during IFN therapy is effective in reducing hepatocarcinogenesis for patients with chronic HCV infection. J. Med. Virol. 79:1485–1490, 2007. © Wiley‐Liss, Inc.
Amino acid substitutions in the VP7 protein of human rotavirus G3 isolated in China, Russia, Thailand, and Vietnam during 2001–2004
Authors: Trinh Quang Duy , Pham Ngan Thi Kim , Nguyen Tuan Anh , Phan Tung Gia , Khamrin Pattara , Yan Hainian , Hoang Phuc Le , Maneekarn Niwat , Li Yan , Kozlov Vladimir , Kozlov Alexei , Okitsu Shoko , Ushijima Hiroshi
Published: August 2007

The distribution of rotavirus G‐types in the world appears to be changing, especially with the emergence of G3 and G9 in many countries. Sequence analysis of the VP7 gene was performed on the 27 human G3 rotavirus strains isolated in China, Russia, Thailand, and Vietnam during 2001–2004. All the strains studied were clustered into the same branch of the phylogenetic tree. The comparison of the G3 deduced amino acid sequences between the studied Chinese strains and the strains circulating in China during 1986–1992 showed a wide range of amino acid substitutions (up to 13 amino acids in the VP7 antigenic regions). The two considerable changes both from aspartic acid to asparagine were located at positions 96 in antigenic region A and 213 in antigenic region C. Those amino acid substitutions of the Chinese G3 strains might involve in the emergence of G3 rotavirus in China during 2001–2003. J. Med. Virol. 79:1611–1616, 2007. © Wiley‐Liss, Inc.
Proteomic analysis of hepatitis B surface antigen positive transgenic mouse liver and decrease of cyclophilin A
Authors: Zhao Chao , Fang Cai‐Yun , Tian Xiao‐Chen , Wang Long , Yang Peng‐Yuan , Wen Yu‐Mei
Published: August 2007

The small, 22‐nm spherical particles associated with hepatitis B infection are composed of hepatitis B surface antigen (HBsAg) and usually outnumber the virions by a ratio of 102 or 103. To study the interactions and pathogenesis between liver cells and the expression of HBsAg, global protein profiles were compared by two dimensional gel‐based differential proteomics between the livers of a lineage of HBsAg positive transgenic mice and their HBsAg negative control siblings. A total of 93 proteins were identified in the HBV transgenic mice. Around 45% of these differentially expressed proteins were enzymes associated with metabolism, suggesting that the processing of lipids, carbohydrates and certain amino acids were up‐ or down‐regulated. Among these proteins, cyclophilin A (CypA), the major target for the potent immunosuppressive drug cyclosporin A, was found decreased in HBsAg positive transgenic mouse liver and in a stable cell line expressing HBsAg when compared to their controls. The decrease of intracellular CypA was accompanied by an increased secretion of this protein into the supernatant of HBsAg positive cells. Possible implications of HBsAg expression and the intracellular decrease of CypA are discussed. J. Med. Virol. 79:1478–1484, 2007. © Wiley‐Liss, Inc.
Molecular and cellular determinants of cell‐to‐cell transmission of HCV in vitro
Authors: Valli Maria Beatrice , Crema Annalisa , Lanzilli Giulia , Serafino Annalucia , Bertolini Luisa , Ravagnan Gianpietro , Ponzetto Antonio , Menzo Stefano , Clementi Massimo , Carloni Guido
Published: August 2007

It was reported previously that HCV can be transmitted from persistently infected human bone‐marrow‐derived B‐lymphoblastoid cells (TO.FEHCV) to human hepatoma cells by cell‐to‐cell contact. The present study confirms and characterize further such type of HCV infection in vitro. TO.FEHCV cells were co‐cultured with 2.2.15 hepatoma cells, that are not susceptible to cell‐free infection by sera containing HCV of 1b genotype. By this co‐cultivation system it was demonstrated that HCV transmission to recipient cells requires de novo virus RNA replication. Several factors may favor HCV‐transmission, evidence is provided that TO.FEHCV cells were able to select HCV‐quasispecies. 5′‐UTR and core sequence analysis revealed differences in the HCV‐quasispecies composition in serum inoculum and in infected TO.FE B‐cells at 4 months post‐inoculation. It is considered that the latter may be more successful in replicating HCV in vitro and used to express surface molecules which may be involved in cell‐to‐cell contact. In TO.FEHCV cells replicate distinct, or few close related, HCV‐variants correlated with those of serum inoculum. Comparative analysis of tetraspans and integrins expression undertaken by cytofluorimetry displayed higher level of expression for TO.FE cells in comparison to other human bone‐marrow‐derived B‐cell lines. Overall, the observed persistent in vitro HCV replication is mediated by a continuous cell‐to‐cell reinfection that may be favored by selection of viral variants and expression of molecules involved in cell adhesion. These observations may provide an explanation for the establishment of HCV infection, the occurrence of chronic infection and HCV‐related lymphoproliferative diseases. J. Med. Virol. 79:1491–1499, 2007. © Wiley‐Liss, Inc.
Tula and Puumala hantavirus NSs ORFs are functional and the products inhibit activation of the interferon‐beta promoter
Authors: Jääskeläinen Kirsi M. , Kaukinen Pasi , Minskaya Ekaterina S. , Plyusnina Angelina , Vapalahti Olli , Elliott Richard M. , Weber Friedemann , Vaheri Antti , Plyusnin Alexander
Published: August 2007

The S RNA genome segment of hantaviruses carried by Arvicolinae and Sigmodontinae rodents encodes the nucleocapsid (N) protein and has an overlapping (+1) open reading frame (ORF) for a putative nonstructural protein (NSs). The aim of this study was to determine whether the ORF is functional. A protein corresponding to the predicted size of Tula virus (TULV) NSs was detected using coupled in vitro transcription and translation from a cloned S segment cDNA, and a protein corresponding to the predicted size of Puumala virus (PUUV) NSs was detected in infected cells by Western blotting with an anti‐peptide serum. The activities of the interferon beta (IFN‐β) promoter, and nuclear factor kappa B (NF‐κB)‐ and interferon regulatory factor‐3 (IRF‐3) responsive promoters, were inhibited in COS‐7 cells transiently expressing TULV or PUUV NSs. Also IFN‐β mRNA levels in IFN‐competent MRC5 cells either infected with TULV or transiently expressing NSs were decreased. These data demonstrate that Tula and Puumala hantaviruses have a functional NSs ORF. The findings may explain why the NSs ORF has been preserved in the genome of most hantaviruses during their long evolution and why hantavirus‐infected cells secrete relatively low levels of IFNs. J. Med. Virol. 79:1527–1536, 2007. © Wiley‐Liss, Inc.
Seroreactivity to Kaposi's sarcoma‐associated herpesvirus (human herpesvirus 8) latent nuclear antigen in AIDS‐associated Kaposi's sarcoma patients depends on CD4+ T‐cell count
Authors: de Souza Vanda Akico Ueda Fick , Pierrotti Ligia Camera , Sumita Laura Masami , Freire Wilton Santos , Segurado Aluisio Augusto Cotrim , Pannuti Cláudio Sérgio
Published: August 2007

In AIDS/Kaposi's sarcoma (KS) patients, the sensitivity of immunofluorescence assays for detecting antibodies against latent nuclear antigen ranges from 52% to 93%. However, in classic and African KS, sensitivities above 90% have been reported systematically. This study evaluates whether CD4+ T‐cell count affects seroreactivity to KSHV LANA and to lytic antigens in AIDS/KS patients. Kaposi's sarcoma‐associated herpesvirus (KSHV) latent (IFA‐LANA) and lytic (IFA‐Lytic and ORF65/K8.1 EIA) antibodies were screened in 184 consecutive samples taken from 36 AIDS/KS patients grouped according to their CD4+ counts as follows: <100 (group A), 100–300 (group B), and >300 (group C) cells/mm3. At enrollment, the immunofluorescence assay for the detection of antibodies against latent nuclear antigen (IFA‐LANA) was positive in 3/11(27.2%) group A patients, in 10/11 (90.9%) group B patients, and in 14/14 (100%) group C patients (P < 0.01). Seropositivity to lytic antigens did not differ according to CD4+ T‐cell count. Considering IFA‐Lytic and ORF65/K8.1 EIA, seropositivity for lytic antigens was 100% in all three patient groups. In patients whose CD4+ count improved during follow‐up, IFA‐LANA seroconversion occurred; unstable counts resulted in a decrease in LANA antibody titers while the persistence of high counts resulted in unchanged, elevated antibody titers. In conclusion, LANA seroreactivity in AIDS/KS patients, as assessed by an immunofluorescence assay, depends on CD4+ T‐cell count, rendering this evaluation important in the interpretation of seroepidemiological studies of KSHV infection in AIDS patients. To evaluate future serological tests based on latency‐associated antigens, the selection of sera from KS patients with CD4+ cell count >300 cells/mm3 as a positive gold standard is recommended. J. Med. Virol. 79:1562–1568, 2007. © Wiley‐Liss, Inc.
Diverse genotypes of Kaposi's sarcoma associated herpesvirus (KSHV) identified in infant blood infections in African childhood‐KS and HIV/AIDS endemic region
Authors: Kasolo F.C. , Spinks J. , Bima H. , Bates M. , Gompels U.A.
Published: August 2007

Kaposi's sarcoma‐associated herpesvirus (KSHV or HHV‐8) has been associated with several neoplasias, including childhood endemic Kaposi's sarcoma (KS). It is possible that strain genotypes could contribute to the differences in regional presentation (mainly sub‐Saharan Africa), childhood infection, lack of male sex bias, distinct disseminated forms and rapid fatality observed for childhood endemic KS. Early studies, at the advent of the HIV/AIDS epidemic, identified only the K1‐A5 genotype in childhood KS biopsies as well as blood of a few HIV positive and negative febrile infants in Zambia, a highly endemic region. This current enlarged study analyses blood infections of 200 hospitalized infants (6–34 months age) with symptoms of fever as well as upper respiratory tract infection, diarrhoea, rash or rhinitis. KSHV and HIV viraemia and were prevalent in this group, 22% and 39%, respectively. Multiple markers at both variable ends of the genome (K1, K12, and K14.1/K15) were examined, showing diverse previously adult‐linked genotypes (K1 A2, A5, B, C3, D, with K12 B1 and B2 plus K14.1/K15 P or M) detected in both HIV positive and negative infants, demonstrating little restriction on KSHV genotypes for infant/childhood transmission in a childhood endemic KS endemic region. This supports the interpretation that the acquisition of childhood KSHV infections and subsequent development of KS are due to additional co‐factors. J. Med. Virol. 79:1555–1561, 2007. © Wiley‐Liss, Inc.
Predictors and kinetics of occult hepatitis B virus infection in HIV‐infected persons
Authors: Nebbia Gaia , Garcia‐Diaz Ana , Ayliffe Ursula , Smith Colette , Dervisevic Samir , Johnson Margaret , Gilson Richard , Tedder Richard , Geretti Anna Maria
Published: August 2007

It has been proposed that occult hepatitis B virus (HBV) infection, defined as detectable HBV‐DNA in serum with undetectable surface antigen (HBsAg−), is associated with raised transaminases in HIV‐infected persons. The aim of this study was to determine the prevalence of occult HBV infection in two independent cohorts, and investigate its predictors, association with alanine‐aminotransferase (ALT) levels and response to antiretroviral therapy. Sera from HBsAg− persons with core antibody (anti‐HBc+) were tested by real‐time PCR. Overall, 5.2% of patients were HBsAg+ and 39% HBsAg−/anti‐HBc+. The prevalence of occult HBV infection was 48/343 (14.0%; 95% CI 10.7–18.1%), and 27/196 (13.8%) and 21/147 (14.3%) in the two cohorts. Median HBV‐DNA load was 342 (51–147,500) and 60 (25–33,850) copies/ml respectively. HBV‐DNA detection was associated with absence of surface antibody (anti‐HBs), but not with CD4 or ALT levels. Among 11 HBV‐DNA+ persons who started antiretroviral therapy containing lamivudine or lamivudine/tenofovir, HBV‐DNA was repeatedly undetectable over median 19 (3–43) months. However, HBV‐DNA detection was intermittent among drug‐naïve persons. Occult HBV infection is common in HBsAg−/anti‐HBc+ HIV‐infected patients and predicted by undetectable anti‐HBs. The intermittent nature of HBV‐DNA detection poses a diagnostic challenge, but no association is observed with ALT levels. J. Med. Virol. 79:1464–1471, 2007. © Wiley‐Liss, Inc.
High diversity of HHV‐8 molecular subtypes in the Amazon region of Brazil: Evidence of an ancient human infection
Authors: Ishak Marluísa de Oliveira Guimarães , Martins Rosimar Neris , Machado Paula Renata Lima , de Souza Lia Lobato Batista , Machado Luiz Fernando Almeida , Azevedo Vânia Nakauth , Katano Harutaka , Sata Tetsutaro , Hasegawa Hideki , Vallinoto Antonio Carlos Rosário , Ishak Ricardo
Published: August 2007

The present study describes the molecular epidemiology of Human herpesvirus 8 (HHV‐8) among four Indian tribes (Kararao, Arara Laranjal, Tiriyo, and Zo'e) of the Amazon region of Brazil and a group of HIV‐1‐infected subjects from the urban population of Belem, Para. Infection was characterized by the presence of antibodies using ELISA (measuring antibodies to ORF59, ORF65, K8.1A, K8.1B, and ORF73), and molecular assays (gene amplification of the regions ORF26 and the variable region VR1). Antibodies to HHV‐8 were detected in 66 samples of the 221 Brazilian Amerindians, namely, 6 (25%) in the Kararao, 18 (19.6%) in the Arara Laranjal, 24 (42.9%) in the Tiriyo, and 18 (36.7%) in the Zo'e. Among the 477 HIV‐1‐infected subjects, antibodies to HHV‐8 were present in 74 (15.5%) persons. The ORF26 region was amplified in seven samples, one of the Arara Laranjal, one of the Tiriyo, two of the Zo'e, and three of the HIV‐1‐infected group. Subtyping of HHV‐8 described a high multiplicity of molecular subtypes, including C (Zo'e), E (Tiriyo), and B (HIV‐1 infected). Serological results confirm the high prevalence of HHV‐8 among Amerindians and the presence of three subtypes in the Amazon region of Brazil, including a unique subtype, which favors the idea of HHV‐8 as an ancient human infection within this particular geographical region. J. Med. Virol. 79:1537–1544, 2007. © Wiley‐Liss, Inc.
Proteomic identification of biomarkers in the cerebrospinal fluid in a rat model of nigrostriatal dopaminergic degeneration
Authors: Rite I. , Argüelles S. , Venero J.L. , García‐Rodriguez S. , Ayala A. , Cano J. , Machado A.
Published: August 2007

We have performed proteomic analysis in the cerebrospinal fluid in an animal model of Parkinson's disease induced by axotomy of the medial forebrain bundle. In this model, the degeneration of dopaminergic neurons was completed in 14 days, with a loss of about 50% dopaminergic neurons in the substantia nigra and a loss of more than 80% dopamine terminals in the striatum, with a similar diminution of dopamine levels in both structures. Proteins were separated by 2D electrophoresis and identified by matrix‐assisted laser desorption‐ionization time‐of‐flight (MALDI‐TOF). We found significant increases of haptoglobin and transthyretin along with a decrease of Apo E concentrations in the cerebrospinal fluid of axotomized animals. Changes for haptoglobin and transthyretin were further confirmed in cerebrospinal fluid and plasma by Western blotting. These results suggest that monitoring plasma levels of these signals appears to be a promising biological marker of neuronal degeneration of the nigrostriatal dopaminergic system. © 2007 Wiley‐Liss, Inc.
Decreased nicotinic receptors and cognitive deficit in rats intracerebroventricularly injected with beta‐amyloid peptide(1‐42) and fed a high‐cholesterol diet
Authors: Liu Ru‐Yu , Gu Ran , Qi Xiao‐Lan , Zhang Ting , Zhao Yan , He Yan , Pei Jin‐Jing , Guan Zhi‐Zhong
Published: August 2007

To investigate whether the changes in nicotinic receptors (nAChRs) and in learning and memory associated with Alzheimer's disease (AD) are influenced by both β‐amyloid peptide (Aβ) and cholesterol in vivo, we examined the effects of intracerebroventricular injection of Aβ1–42 and/or a high‐cholesterol diet on brain levels ofnAChRs and learning and memory in rats. The levels of nAChR subunit proteins and the corresponding mRNA were measured by Western blotting and RT‐PCR, respectively; and learning and memory were evaluated with the Morris Water Maze examination. Injection of Aβ1–42 resulted in deposition of this peptide, activation of astrocytes, decreased levels of the α7 and α4 protein subunits of the nAChR, and elevated expression of α7 mRNA, as well as impaired learning and spatial memory. A high‐cholesterol diet activated astrocytes and, more importantly, potentiated the toxic effects of Aβ on nAChR subunit levels and on learning and memory. These findings may be highly relevant to the mechanisms underlying the cognitive deficits associated with AD. © 2007 Wiley‐Liss, Inc.
Turning managers into leaders: assessing the organizational impact of leadership development
Authors: Dexter Barbara , Prince Christopher
Published: August 2007

This paper seeks to assess the impact of a leadership development programme on the individual managers participating in it and its effect on the overall performance of the organization. The paper is structured as follows. It begins with a review of the contemporary literature on leadership and management development. It then examines the content and structure of the leadership programme and the methodology used to evaluate its success.

The research findings examined here are structured around four themes: contribution to better processes and project management, more effective team working, developing networks and collaborative working, and improved self‐management. There is compelling evidence of how the programme has contributed to both the development of the individual managers and organizational improvement.

Copyright © 2007 John Wiley & Sons, Ltd.
Integrating sustainable tourism and marketing management: can National Parks provide the framework for strategic change?
Authors: Gilmore Audrey , Simmons Geoff
Published: August 2007

This paper argues that strategic marketing management can play an important role in the development of sustainable tourism principles within National Parks. Sustainable tourism marketing—incorporating social, economic and environmental perspectives—is discussed.

The research presented here focused on two key themes: the integration and co‐ordination of tourism activity (delivered by different organizations), and use of strategic marketing for sustainable tourism initiatives (marketing issues, interpretation, branding, communication messages).

It reports on two case studies, one of an Area of Outstanding Natural Beauty (AONB) soon to be designated as a National Park and the other of an already well‐established National Park to illustrate the key issues involved in achieving strategic change in terms of a sustainable marketing ethos within such an environment.

A principal finding is that the National Park designation appears to provide a strategic framework for sustainable tourism. However, the designation has a limited impact in terms of actual implementation of policies and guidelines and in persuading all relevant tourist service providers to participate.

Copyright © 2007 John Wiley & Sons, Ltd.
Real‐Time Observations of Oriented Crystallization of Poly(ε‐caprolactone) Thin Film, Induced by an AFM Tip
Authors: Fujita Masahiro , Takikawa Yoshitaka , Sakuma Hirotaka , Teramachi Shinya , Kikkawa Yoshihiro , Doi Yoshiharu
Published: August 2007

Atomic force microscopy (AFM) was used for modifying the surface structures of poly(ε‐caprolactone) (PCL) thin film. Oriented growth of PCL crystals at a desired area of the film surface was induced by scanning with a strong, normal load. PCL crystals were first grown edge‐on from the induction line and then their orientation changed to flat‐on at a lamellar length. The effects of molecular weight, crystallization temperature, scanning rate, and normal load on the AFM‐tip‐induced crystallization were examined. The growth kinetics of lamellar crystals in the AFM‐tip‐induced crystallization was the same as that in spherulitic crystallization. It was found that the formation of precursors strongly depends on the applied tip load and is facilitated when the applied load is higher than a threshold.

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3‐Butyl‐2‐yl‐ and Propargyl Cholesteryl Carbonates. Chiroptical and Liquid Crystalline Properties of their Polymers
Authors: Qu Jinqing , Suzuki Yuji , Shiotsuki Masashi , Sanda Fumio , Masuda Toshio
Published: August 2007

Novel chiral acetylene monomers containing cholesteryl groups, (R)‐3‐butyn‐2‐yl cholesteryl carbonate (1), (S)‐3‐butyn‐2‐yl cholesteryl carbonate (2), and propargyl cholesteryl carbonate (3) were synthesized and polymerized with (nbd)Rh+[η6‐C6H5B−(C6H5)3] to give the corresponding polymers with number‐average molecular weights of 32 900–97 000 in 84–85% yields. Circular dichroism spectroscopic studies revealed that poly(1) and poly(2) predominantly took one‐handed helical structure in CHCl3 and THF. The helical conformation was stable to heat and to addition of MeOH. The copolymerization of 1 and 2 was carried out with the rhodium catalyst to afford copolymers with number‐average molecular weights ranging from 53 400 to 88 700 in 83–98% yields. The copolymer with a large diastereomeric excess showed a large specific rotation and an intense Cotton effect in THF, indicating that the predominance of one‐handed helicity was high. Poly(150‐co‐250) showed lyotropic liquid crystalline property.

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Processing and Material Characteristics of a Carbon‐Nanotube‐Reinforced Natural Rubber
Authors: Sui Gang , Zhong Weihong , Yang Xiaoping , Zhao Suhe
Published: August 2007

CNT/NR composites were fabricated based on a CNT treatment using an acid bath followed by ball‐milling with HRH bonding systems. Thermal properties, vulcanization characteristics and mechanical properties of the CNT/NR composites were characterized. Compared to CB, the incorporation of CNTs into NR was faster and the energy consumption was less. The over‐curing reversion of CNT/NR composites was alleviated. After acid treatment and ball‐milling, the dispersion of CNTs in the rubber matrix and the interaction between CNTs and the matrix was improved. The performance of the CNT/reinforced NR composites was enhanced by the incorporation of the treated CNTs as compared to neat NR and CB/NR composites.

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Oligomers and Polymers Based on Bridged Phenylenes as Electronic Materials
Authors: Grimsdale Andrew C. , Müllen Klaus
Published: August 2007

The synthesis, properties, and application in electronic devices of ladder and step‐ladder phenylene‐based oligomers and polymers are reviewed with an emphasis on control of properties by synthetic design. Bridged polyphenylenes can be prepared with a range of different amounts and types of bridges. Fully bridged polymers suffer the problem of incomplete formation of bridges during polymer analogous reactions. This problem is surmounted by the synthesis of regular stepladder polymers in which the monomers are well‐characterized oligo(ladder‐phenylene)s. By controlling the degree of bridging and thus the planarity of the polymer, its optical properties can be tuned. The optical and electronic properties can be further controlled by means of the type of bridges used.

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Cationic Polymerization of Poly(vinyl ether) Bearing a TEMPO Radical: A New Cathode‐Active Material for Organic Radical Batteries
Authors: Suguro Masahiro , Iwasa Shigeyuki , Kusachi Yuki , Morioka Yukiko , Nakahara Kentaro
Published: August 2007

PTVE was synthesized as a new active material for organic radical batteries. Cationic polymerization of a monomer bearing a TEMPO radical moiety took place. The spin concentration of PTVE was estimated to be 2.75 × 1021 spins · g−1 (100% spin per repeating unit). The PTVE is extremely stable; there is no decrease in spin concentration when storing PTVE samples for more than a year under aerobic conditions at room temperature. The redox potential of PTVE is 3.55 V (vs. Li/Li+). A coin‐type cell using a PTVE/VGCF composite electrode was also fabricated, and then performed charge/discharge measurements. The discharge capacity of PTVE is 114 mAh · g−1 (84% of the theoretical value).

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Exploring Polymers of Intrinsic Microporosity – Microporous, Soluble Polyamide and Polyimide
Authors: Weber Jens , Su Qi , Antonietti Markus , Thomas Arne
Published: August 2007

Polyamides and polyimides featuring a spirobifluorene unit as a structure directing motif in the polymer chain show intrinsic microporosity and consequently high surface areas. Such a spirobifluorene generates a 90° kink per repeating unit and thus prevents space‐efficient packing or crystallization of the otherwise stiff polymer chains. Thus, the approach presented here extends the concept of polymers of intrinsic microporosity for ladder type poly(dibenzodioxane)s to more common polymers of high commercial interest. For example, a microporous polyimide with a surface area of ≈550 m2 · g−1 was produced, which is readily soluble in chloroform.

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The Effect of Substrate on the Annealing of Poly(butylene succinate) Single Crystals
Authors: Wang Xiaohong , Zhou Jianjun , Li Lin , Chan Chi‐Ming
Published: August 2007

The morphological evolution of poly(butylene succinate) (PBS) solution‐grown single crystals during annealing was studied using hot‐stage atomic force microscopy. Their morphology changed with increasing temperature and annealing time. The annealing behavior and melting temperature were found to be affected by the substrate. Morphological changes occurred at a much lower temperature on an amorphous carbon film than that on a mica surface. Moreover, the pattern of morphological evolution of the single crystals on a carbon film was different from that on a mica surface. Since the PBS melt had a larger contact angle on the mica surface, these differences in the melting behavior were ascribed to the different interfacial interactions between the chain‐folded surface of the single crystal and the substrate.

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