bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reactive oxygen species and p38 mitogen‐activated protein kinase induce apoptotic death of U937 cells in response to Naja nigricollis toxin‐γ
Authors: Liu Wen‐Hsin , Chang Long‐Sen 
Published: August 2008

AbstractThe aim of the present study is to elucidate the signalling components related to Naja nigricollis toxin‐γ‐induced apoptosis in human leukaemia U937 cells. It was found that toxin‐γ‐induced apoptotic cell death was attributed mainly to activation of p38 mitogen‐activated protein kinase (MAPK), reactive oxygen species (ROS) generation and loss of mitochondrial membrane potential (ΔΨm). Subsequent modulation of Bcl‐2 family member and cytochrome c release accompanied with activation of caspase‐9 and ‐3 were involved in the death of U937 cells. SB202190 (p38 MAPK inhibitor) and N‐acetylcysteine (antioxidant) significantly attenuated toxin‐γ‐induced cell death and loss of ΔΨm, and completely abolished the production of ROS. In contrast to N‐acetylcysteine, degradation of Bcl‐2/Bcl‐XL and mitochondrial localization of Bax were notably decreased by SB202190. Inhibitors of electron transport (rotenone and antimycin A) or inhibitor of mitochondrial permeability transition pore (cyclosporine A) reduced the effect of toxin‐γ on ROS generation, loss of ΔΨm and cytochrome c release. Noticeably, pre‐treatment with N‐acetylcysteine or rotenone eliminated markedly ROS accompanied with reduction in p38 MAPK activation. Taken together, these results suggest that the cytotoxicity of toxin‐γ is initiated by p38‐MAPK‐mediated mitochondrial dysfunction followed by ROS production and activation of caspases, and that ROS further augments p38 MAPK activation and mitochondrial alteration.
The behavior of stem cells and progenitor cells in the periodontal ligament during wound healing as observed using immunohistochemical methods
Authors: Ohta S. , Yamada S. , Matuzaka K. , Inoue T. 
Published: August 2008

Background and Objective:  The aim of this study was to identify stem cells or progenitor cells in the periodontal ligament and to investigate their behavior during wound healing of bone defects created experimentally in the alveolar process.Material and Methods:  Intradentinal cavities were created in the mesial root of the first molar of 25 adult male rats that were killed 1, 3, 5, 7 and 14 d after surgery. At each time‐point, sections were stained immunohistochemically for CD44s (standard), CD34, c‐KIT, PCNA, Cbfa‐1 and 5‐bromo‐2‐deoxyuridine using primary antibodies. For morphometric analysis, the ratios of Cbfa‐1 and PCNA‐positive cells were calculated from the total number of positive cells/104 µm2 in the cavities.Results:  5‐Bromo‐2‐deoxyuridine‐positive cells were observed in the periodontal ligament and had migrated into the wound areas. A small number of CD44s‐, CD34‐ and c‐KIT‐positive cells were observed in the bone marrow, but none were observed in the periodontal ligament. CD44s‐positive cells were only observed in the alveolar bone cavity at 5 d after surgery. CD34‐ and c‐KIT‐positive cells were only observed in the dentin cavity at 7 d after surgery. Cbfa‐1 and PCNA scores tended to show an increase 7 d after surgery.Conclusion:  Mesenchymal stem cells and hematopoietic stem cells in the bone marrow are not involved in the regeneration of the periodontium. Cells that migrated from the residual periodontal ligament regenerated new alveolar bone at the early stage, and the regeneration around the dentin in the cavity was later than in other parts.
Lower antibody response to Porphyromonas gingivalis associated with immunoglobulin G Fcγ receptor IIB polymorphism
Authors: Honma Y. , Sugita N. , Kobayashi T. , Abiko Y. , Yoshie H. 
Published: August 2008

Background and Objective:  Human FcγRIIB is one of the receptors for immunoglobulin G (IgG) and suppresses the activation of B lymphocytes through cross‐linking with the B cell receptor via immune complexes. This function of FcγRIIB is essential for the negative regulation of antibody production. Our previous study has demonstrated the gene polymorphism FcγRIIB‐I232T to be associated with periodontitis. The polymorphism FcγRIIB‐232T has been reported to inhibit B‐cell antigen receptor signaling more effectively compared to FcγRIIB‐232I, while other groups concluded that FcγRIIB‐232T had no ability to inhibit activatory receptors. In this study, we examined whether FcγRIIB‐I232T polymorphism would change the IgG antibody response to the periodontopathic bacteria Porphyromonas gingivalis.Material and Methods:  Forty‐seven patients with periodontitis were genotyped with the direct sequencing of genome DNA. Serum IgG and specific IgG subclass levels for the sonicate of P. gingivalis and the recombinant 40 kDa outer membrane protein (OMP) were determined.Results:  No significant difference in the total IgG level and IgG response to P. gingivalis sonicate were observed between sera from FcγRIIB‐232T carriers and non‐carriers. The FcγRIIB‐232T carriers revealed a significantly lower IgG2 response to P. gingivalis 40 kDa OMP compared to non‐carriers (p = 0.04, Mann–Whitney U‐test). Lower responses of FcγRIIB‐232T carriers were also observed in specific IgG and IgG1 levels. The FcγRIIB‐232T carriers revealed a low level of IgG2 response to P. gingivalis 40 kDa OMP, even with a high average probing pocket depth.Conclusion:  These results suggest that association of the FcγRIIB‐232T allele with periodontitis might be related to the lower levels of antibody response to P. gingivalis.
ORIGINAL ARTICLE: Interleukin 1 Receptor Antagonist Gene Polymorphisms Are Not Risk Factors for Recurrent Pregnancy Loss: Evaluation of Couples
Authors: Levrant Seth , Coulam Carolyn B. , Jeyendran Rajasingam S. 
Published: August 2008

Problem  The interleukin‐1 system has been implicated in pregnancy outcome. Fetal carriage of interleukin‐1 receptor antagonist (IL‐1Ra) specific alleles has been associated with adverse pregnancy outcomes including spontaneous abortion and pre‐term labor. This study was undertaken to compare the frequency of IL‐1RN*2 alleles among both male and female partners of couples experiencing recurrent pregnancy loss with that of fertile control couples.Method of study  Buccal swabs were obtained from 42 couples experiencing recurrent pregnancy loss and from 20 fertile control couples. DNA was extracted from the buccal swabs and analyzed for the presence of IL‐1RN variable number tandem repeat.Results  No significant differences were found when the frequency of IL‐1RN*2 polymorphisms were compared between fertile control couples and couples experiencing recurrent pregnancy loss. Similar results were also obtained when comparing women or men respectively from each group.Conclusion  IL‐1RN*2 allele is not a risk factor for recurrent pregnancy loss.
Analytic expressions for the surface brightness profile of gamma-ray burst afterglow images
Authors: Granot Jonathan 
Published: August 2008

Abstract
The exact profile of a gamma-ray burst afterglow image on the plane of the sky can provide important constraints on the underlying physics. In particular, it can test whether the magnetic field in the emitting shocked external medium decreases significantly with the distance behind the shock front, or remains roughly constant. Moreover, it enables more accurate measurements of the afterglow image size and the expected scintillation properties. In this work, analytic expressions are derived for the afterglow image in power-law segments (PLSs) of the afterglow synchrotron spectrum in which the emission originates from a very thin layer just behind the shock, while simple semi-analytic expressions are derived for the remaining PLSs in which the emission arises from the bulk of the shocked fluid. In all cases, the expressions are for a general power-law external density profile, and are convenient to use in afterglow studies.
Characteristics of Salmonella Contamination of Broilers and Slaughterhouses in the Region of Constantine (Algeria)
Authors: Elgroud R. , Zerdoumi F. , Benazzouz M. , Bouzitouna‐Bentchouala C. , Granier S. A. , Frémy S. , Brisabois A. , Dufour B. , Millemann Y. 
Published: August 2008

SummaryThe present study provides the first data about the prevalence of Salmonella contamination of broilers and slaughterhouses in the region of Constantine, Algeria. The serotypes and anti‐microbial resistance phenotypes of the isolates were determined, and risk factors contributing to the contamination were evaluated. A total of 2490 samples, 1800 originating from 30 broiler farms and 690 from 15 slaughterhouses, were taken during two periods: March 2005–June 2006 and September 2006–March 2007. Salmonella contamination concerned 37% of the broiler farms and 53% of the slaughterhouses. Among the 55 isolates recovered, 10 different serotypes were identified. The most frequently recovered serotypes in both slaughterhouses and breeder farms were S. Hadar (36%, n = 20), S. Virchow (16%, n = 9), S. Infantis (10.9%, n = 6), S. Albany (11%, n = 6) and S. Carnac (7%, n = 4). Isolates belonging to S. Heidelberg (2%, n = 1) and S. Rissen (2%, n = 1) were found only in farms, while those belonging to S. Typhimurium (9%, n = 5), S. Enteritidis (4%, n = 2) and S. Montevideo (2%, n = 1) were recovered only from slaughterhouses. Thirty‐nine isolates (80%) were resistant to at least one anti‐microbial and 51% were multi‐resistant, i.e. resistant to two or more anti‐microbial molecules. About 58% (n = 32) were resistant to streptomycin, 36% (n = 20) to tetracyclines, 27% (n = 15) to nalidixic acid, 13% (n = 7) to ofloxacin and one isolate to enrofloxacin. Finally, seven distinct anti‐microbial resistance profiles were identified. In parallel, four risk factors were found to be significantly associated with Salmonella contamination. Together with the huge spread of Salmonella in the broiler production chain in Constantine, Algeria, these risk factors highlight the hazards of the broiler channels, particularly linked to poor technical and hygiene practices.
Clinical and Immunologic Features of an Atypical IntracranialMycobacterium aviumComplex (MAC) Infection Compared with Those of Pulmonary MAC Infections
Authors: Sadek Mouhannad , Yue Feng Yun , Lee Erika Yue , Gyenes Gabor , Jones R. Brad , Hoffstein Victor , Munoz David G. , Fong Ignatius , Ostrowski Mario 
Published: August 2008

ABSTRACTMembers of theMycobacterium aviumcomplex (MAC) may cause chronic pulmonary infections in otherwise healthy elderly persons but rarely invade parts of the body outside of the lungs in immunocompetent hosts. We present a case of an isolated intracranial MAC infection in an apparently immunocompetent individual and review previous reports. We studied the T-cell and monocyte responses in healthy volunteers, individuals with a pulmonary MAC infection, and one individual with an isolated intracranial MAC infection. Genomic DNA from the individual with the brain MAC infection was studied for gamma interferon (IFN-γ) receptor mutations. Individuals with localized pulmonary MAC infections showed increased activation of monocytes and enhanced monocyte and T-cell tumor necrosis factor alpha (TNF-α) production in response to lipopolysaccharide and MAC antigens but defects in T-cell IFN-γ secretion. The individual with an intracranial MAC infection showed a lack of monocyte activation and deficiencies in both monocyte and T-cell TNF-α production and monocyte interleukin-12 (IL-12) production but had preserved T-cell IFN-γ production. Mutations or deletions in the IFN-γ receptor were not detected in the individual with the intracranial MAC infection. Our data suggest that distinct immune defects characterize two different manifestations of MAC infection. A relative defect in IFN-γ production in response to MAC may predispose an individual to localized but partially controlled lung disease, whereas defects leading to reduced IL-12 and TNF-α production may allow the dissemination of MAC. Further studies delineating the potential role of TNF-α in limiting the spread of MAC outside the lung are warranted.
In Vitro Natamycin Susceptibility of Ocular Isolates ofFusariumandAspergillusSpecies: Comparison of Commercially Formulated Natamycin Eye Drops to Pharmaceutical-Grade Powder
Authors: Lalitha P. , Vijaykumar R. , Prajna N. V. , Fothergill A. W. 
Published: August 2008

ABSTRACTThe Clinical and Laboratory Standards Institute susceptibility method prohibits the use of pharmacy preparations, but obtaining pure powders is difficult. The activity of natamycin against isolates ofAspergillusandFusariumspecies isolated from keratitis was assessed by using both powder and pharmacy eye drop preparations. Eye drop preparations may be a viable option for testing natamycin activity.
Binding STAT2 by the Acidic Domain of Human Cytomegalovirus IE1 Promotes Viral Growth and Is Negatively Regulated by SUMO
Authors: Huh Yong Ho , Kim Young Eui , Kim Eui Tae , Park Jung Jin , Song Moon Jung , Zhu Hua , Hayward Gary S. , Ahn Jin-Hyun 
Published: August 2008

ABSTRACT
The human cytomegalovirus (HCMV) 72-kDa immediate-early 1 (IE1) protein is thought to modulate cellular antiviral functions impacting on promyelocytic leukemia (PML) nuclear bodies and signal transducer and activator of transcription (STAT) signaling. IE1 consists of four distinct regions: an amino-terminal region required for nuclear localization, a large central hydrophobic region responsible for PML targeting and transactivation activity, an acidic domain, and a carboxyl-terminal chromatin tethering domain. We found that the acidic domain of IE1 is required for binding to STAT2. A mutant HCMV encoding IE1(Δ421-475) with the acidic domain deleted was generated. In mutant virus-infected cells, IE1(Δ421-475) failed to bind to STAT2. The growth of mutant virus was only slightly delayed at a high multiplicity of infection (MOI) but was severely impaired at a low MOI with low-level accumulation of viral proteins. When cells were pretreated with beta interferon, the mutant virus showed an additional 1,000-fold reduction in viral growth, even at a high MOI, compared to the wild type. The inhibition of STAT2 loading on the target promoter upon infection was markedly reduced with mutant virus. Furthermore, sumoylation of IE1 at this acidic domain was found to abolish the activity of IE1 to bind to STAT2 and repress the interferon-stimulated genes. Our results provide genetic evidence that IE1 binding to STAT2 requires the 55-amino-acid acidic domain and promotes viral growth by interfering with interferon signaling and demonstrate that this viral activity is negatively regulated by a cellular sumoylation pathway.
NF-κB Signaling Differentially Regulates Influenza Virus RNA Synthesis
Authors: Kumar Naveen , Xin Zhong-tao , Liang Yuhong , Ly Hinh , Liang Yuying 
Published: August 2008

ABSTRACTThe NF-κB signaling pathway has previously been shown to be required for efficient influenza A virus replication, although the molecular mechanism is not well understood. In this study, we identified a specific step of the influenza virus life cycle that is influenced by NF-κB signaling by using two known NF-κB inhibitors and a variety of influenza virus-specific assays. The results of time course experiments suggest that the NF-κB inhibitors Bay11-7082 and ammonium pyrrolidinedithiocarbamate inhibited an early postentry step of viral infection, but they did not appear to affect the nucleocytoplasmic trafficking of the viral ribonucleoprotein complex. Instead, we found that the levels of influenza virus genomic RNA (vRNA), but not the corresponding cRNA or mRNA, were specifically reduced by the inhibitors in virus-infected cells, indicating that NF-κB signaling is intimately involved in the vRNA synthesis. Furthermore, we showed that the NF-κB inhibitors specifically diminished influenza virus RNA transcription from the cRNA promoter but not from the vRNA promoter in a reporter assay, a result which is consistent with data obtained from virus-infected cells. The overexpression of the p65 NF-κB molecule could not only eliminate the inhibition but also activate influenza virus RNA transcription from the cRNA promoter. Finally, using p65-specific small interfering RNA, we have shown that p65 knockdown reduced the levels of influenza virus replication and vRNA synthesis. In summary, we have provided evidence showing, for the first time, that the NF-κB host signaling pathway can differentially regulate influenza virus RNA synthesis, which may also offer some new perspectives into understanding the host regulation of RNA synthesis by other RNA viruses.
Detecting Small Changes and Additional Peptides in the Canine Parvovirus Capsid Structure
Authors: Nelson Christian D. S. , Minkkinen Eveliina , Bergkvist Magnus , Hoelzer Karin , Fisher Mathew , Bothner Brian , Parrish Colin R. 
Published: August 2008

ABSTRACT
Parvovirus capsids are assembled from multiple forms of a single protein and are quite stable structurally. However, in order to infect cells, conformational plasticity of the capsid is required and this likely involves the exposure of structures that are buried within the structural models. The presence of functional asymmetry in the otherwise icosahedral capsid has also been proposed. Here we examined the protein composition of canine parvovirus capsids and evaluated their structural variation and permeability by protease sensitivity, spectrofluorometry, and negative staining electron microscopy. Additional protein forms identified included an apparent smaller variant of the virus protein 1 (VP1) and a small proportion of a cleaved form of VP2. Only a small percentage of the proteins in intact capsids were cleaved by any of the proteases tested. The capsid susceptibility to proteolysis varied with temperature but new cleavages were not revealed. No global change in the capsid structure was observed by analysis of Trp fluorescence when capsids were heated between 40°C and 60°C. However, increased polarity of empty capsids was indicated by bis-ANS binding, something not seen for DNA-containing capsids. Removal of calcium with EGTA or exposure to pHs as low as 5.0 had little effect on the structure, but at pH 4.0 changes were revealed by proteinase K digestion. Exposure of viral DNA to the external environment started above 50°C. Some negative stains showed increased permeability of empty capsids at higher temperatures, but no effects were seen after EGTA treatment.
The Vaccinia Virus Gene I2L Encodes a Membrane Protein with an Essential Role in Virion Entry
Authors: Nichols R. Jeremy , Stanitsa Eleni , Unger Bethany , Traktman Paula 
Published: August 2008

ABSTRACT
The previously unstudied vaccinia virus gene I2L is conserved in all orthopoxviruses. We show here that the 8-kDa I2 protein is expressed at late times of infection, is tightly associated with membranes, and is encapsidated in mature virions. We have generated a recombinant virus in which I2 expression is dependent upon the inclusion of tetracycline in the culture medium. In the absence of I2, the biochemical events of the viral life cycle progress normally, and virion morphogenesis culminates in the production of mature virions. However, these virions show an ∼400-fold reduction in specific infectivity due to an inability to enter target cells. Several proteins that have been previously identified as components of an essential entry/fusion complex are present at reduced levels in I2-deficient virions, although other membrane proteins, core proteins, and DNA are encapsidated at normal levels. A preliminary structure/function analysis of I2 has been performed using a transient complementation assay: the C-terminal hydrophobic domain is essential for protein stability, and several regions within the N-terminal hydrophilic domain are essential for biological competency. I2 is thus yet another component of the poxvirus virion that is essential for the complex process of entry into target cells.
Possible Role for Cellular Karyopherins in Regulating Polyomavirus and Papillomavirus Capsid Assembly
Authors: Bird Gregory , O'Donnell Malinda , Moroianu Junona , Garcea Robert L. 
Published: August 2008

ABSTRACT
Polyomavirus and papillomavirus (papovavirus) capsids are composed of 72 capsomeres of their major capsid proteins, VP1 and L1, respectively. After translation in the cytoplasm, L1 and VP1 pentamerize into capsomeres and are then imported into the nucleus using the cellular α and β karyopherins. Virion assembly only occurs in the nucleus, and cellular mechanisms exist to prevent premature capsid assembly in the cytosol. We have identified the karyopherin family of nuclear import factors as possible “chaperones” in preventing the cytoplasmic assembly of papovavirus capsomeres. Recombinant murine polyomavirus (mPy) VP1 and human papillomavirus type 11 (HPV11) L1 capsomeres bound the karyopherin heterodimer α2β1 in vitro in a nuclear localization signal (NLS)-dependent manner. Because the amino acid sequence comprising the NLS of VP1 and L1 overlaps the previously identified DNA binding domain, we examined the relationship between karyopherin and DNA binding of both mPy VP1 and HPV11 L1. Capsomeres of L1, but not VP1, bound by karyopherin α2β1 or β1 alone were unable to bind DNA. VP1 and L1 capsomeres could bind both karyopherin α2 and DNA simultaneously. Both VP1 and L1 capsomeres bound by karyopherin α2β1 were unable to assemble into capsids, as shown by in vitro assembly reactions. These results support a role for karyopherins as chaperones in the in vivo regulation of viral capsid assembly.
Monomeric Linear RNA of
Citrus Exocortis Viroid
Resulting from Processing In Vivo Has 5′-Phosphomonoester and 3′-Hydroxyl Termini: Implications for the RNase and RNA Ligase Involved in Replication
Authors: Gas María-Eugenia , Molina-Serrano Diego , Hernández Carmen , Flores Ricardo , Daròs José-Antonio 
Published: August 2008

ABSTRACT

Members of the family
Pospiviroidae
, like
Citrus exocortis viroid
(CEVd), replicate through an RNA-based asymmetric rolling-circle mechanism in which oligomeric plus-strand [(+)] RNA intermediates are cleaved to monomeric linear (
ml
) RNA and then circularized. Here we show, by rapid amplification of 5′ and 3′ cDNA ends and in vitro ligation assays, that
ml
CEVd (+) RNA resulting from cleavage of a dimeric transcript transgenically expressed in
Arabidopsis thaliana
contains 5′-phosphomonoester and 3′-hydroxyl termini. The nature of these termini and the double-stranded structure previously proposed as the substrate for cleavage in vivo suggest that a type III RNase catalyzes cleavage and an RNA ligase distinct from tRNA ligase promotes circularization.
MAINTAINING DATA DEPENDENCIES ACROSS BPEL PROCESS FRAGMENTS
Authors: KHALAF RANIA , KOPP OLIVER , LEYMANN FRANK 
Published: August 2008

Continuous process improvement (CPI) may require a BPEL process to be split amongst different participants. In this paper, we enable splitting standard BPEL — without requiring any new middleware for the case of flat flows. The solution also supports splitting loops and scopes that have compensation and/or fault handlers. When splitting loops and scopes, we extend existing Web services standards and frameworks in a standard compliant manner in order to support the resulting split control (not data) between the fragments. Data dependencies, however, are handled directly using BPEL constructs placed in the fragments even for split loops and scopes. We present a solution that uses a BPEL process, partition information, and results of data-flow analysis to produce a BPEL process for each participant. The collective behavior of these participant processes recreates the control and data flow of the non-split process. Previous work presented process splitting using a variant of BPEL where data flow is modeled explicitly using "data links". We reuse the control flow aspect from that work as well as the control flow aspect from our work on splitting loops and scopes, focusing in this paper on maintaining the data dependencies in standard BPEL.