bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tetramer Enrichment Reveals the Presence of Phenotypically Diverse Hepatitis C Virus-Specific CD8
+
T Cells in Chronic Infection
Authors: Nitschke Katja , Flecken Tobias , Schmidt Julia , Gostick Emma , Marget Matthias , Neumann-Haefelin Christoph , Blum Hubert E. , Price David A. , Thimme Robert 
Published: October 2014

ABSTRACT

Virus-specific CD8
+
T cells are rarely detectable
ex vivo
by conventional methods during chronic hepatitis C virus (HCV) infection. In this study, however, we were able to detect and characterize HCV-specific CD8
+
T cells in all chronically HCV genotype 1a-infected, HLA-A*02:01-positive patients analyzed by performing major histocompatibility complex (MHC) class I tetramer enrichment. Two-thirds of these enriched HCV-specific CD8
+
T-cell populations displayed an effector memory phenotype, whereas, surprisingly, one-third displayed a naive-like phenotype despite ongoing viral replication. CD8
+
T cells with an effector memory phenotype could not expand
in vitro
, suggesting exhaustion of these cells. Interestingly, some of the naive-like CD8
+
T cells proliferated vigorously upon
in vitro
priming, whereas others did not. These differences were linked to the corresponding viral sequences in the respective patients. Indeed, naive-like CD8
+
T cells from patients with the consensus sequence in the corresponding T-cell epitope did not expand
in vitro
. In contrast, in patients displaying sequence variations, we were able to induce HCV-specific CD8
+
T-cell proliferation, which may indicate infection with a variant virus. Collectively, these data reveal the presence of phenotypically and functionally diverse HCV-specific CD8
+
T cells at very low frequencies that are detectable in all chronically infected patients despite viral persistence.

IMPORTANCE
In this study, we analyzed CD8
+
T-cell responses specific for HLA-A*02:01-restricted epitopes in chronically HCV-infected patients, using MHC class I tetramer enrichment. Importantly, we could detect HCV-specific CD8
+
T-cell populations in all patients. To further characterize these HCV-specific CD8
+
T-cell populations that are not detectable using conventional techniques, we performed phenotypic, functional, and viral sequence analyses. These data revealed different mechanisms for CD8
+
T-cell failure in HCV infection, including T-cell exhaustion, viral escape, and functional impairment of naive-like HCV-specific CD8
+
T cells.
Contact-Induced Mitochondrial Polarization Supports HIV-1 Virological Synapse Formation
Authors: Groppelli Elisabetta , Starling Shimona , Jolly Clare 
Published: October 2014

ABSTRACTRapid HIV-1 spread between CD4 T lymphocytes occurs at retrovirus-induced immune cell contacts called virological synapses (VS). VS are associated with striking T cell polarization and localized virus budding at the site of contact that facilitates cell-cell spread. In addition to this, spatial clustering of organelles, including mitochondria, to the contact zone has been previously shown. However, whether cell-cell contact specifically induces dynamic T cell remodeling during VS formation and what regulates this process remain unclear. Here, we report that contact between an HIV-1-infected T cell and an uninfected target T cell specifically triggers polarization of mitochondria concomitant with recruitment of the major HIV-1 structural protein Gag to the site of cell-cell contact. Using fixed and live-cell imaging, we show that mitochondrial and Gag polarization in HIV-1-infected T cells occurs within minutes of contact with target T cells, requires the formation of stable cell-cell contacts, and is an active, calcium-dependent process. We also find that perturbation of mitochondrial polarization impairs cell-cell spread of HIV-1 at the VS. Taken together, these data suggest that HIV-1-infected T cells are able to sense and respond to contact with susceptible target cells and undergo dynamic cytoplasmic remodeling to create a synaptic environment that supports efficient HIV-1 VS formation between CD4 T lymphocytes.IMPORTANCEHIV-1 remains one of the major global health challenges of modern times. The capacity of HIV-1 to cause disease depends on the virus's ability to spread between immune cells, most notably CD4 T lymphocytes. Cell-cell transmission is the most efficient way of HIV-1 spread and occurs at the virological synapse (VS). The VS forms at the site of contact between an infected cell and an uninfected cell and is characterized by polarized assembly and budding of virions and clustering of cellular organelles, including mitochondria. Here, we show that cell-cell contact induces rapid recruitment of mitochondria to the contact site and that this supports efficient VS formation and consequently cell-cell spread. Additionally, we observed that cell-cell contact induces a mitochondrion-dependent increase in intracellular calcium, indicative of cellular signaling. Taken together, our data suggest that VS formation is a regulated process and thus a potential target to block HIV-1 cell-cell spread.
Murine Cytomegalovirus Is Not Restricted to the House Mouse Mus musculus domesticus: Prevalence and Genetic Diversity in the European House Mouse Hybrid Zone
Authors: Goüy de Bellocq Joëlle , Baird Stuart J. E. , Albrechtová Jana , Sobeková Karolína , Piálek Jaroslav 
Published: October 2014

ABSTRACT

Murine cytomegalovirus (MCMV) is a betaherpesvirus of the house mouse,
Mus musculus domesticus
. It is a common infectious agent of wild mice and a highly studied pathogen of the laboratory mouse. Betaherpesviruses are specific to their hosts, and it is not known if other
Mus
taxa carry MCMV or if it is restricted to
M. m. domesticus
. We sampled mice over a 145-km transect of Bavaria-Bohemia crossing a hybrid zone between
M. m. domesticus
and
Mus musculus musculus
in order to investigate the occurrence of MCMV in two
Mus
subspecies and to test the limits of the specificity of the virus for its host. We hypothesized that if the two subspecies carry MCMV and if the virus is highly specific to its host, divergent MCMV lineages would have codiverged with their hosts and would have a geographical distribution constrained by the host genetic background. A total of 520 mice were tested by enzyme-linked immunosorbent assay (ELISA) and/or nested PCR targeting the M94 gene. Seropositive and PCR-positive individuals were found in both
Mus
subspecies. Seroprevalence was high, at 79.4%, but viral DNA was detected in only 41.7% of mice. Sequencing revealed 20 haplotypes clustering in 3 clades that match the host genetic structure in the hybrid zone, showing 1 and 2 MCMV lineages in
M. m. domesticus
and
M. m. musculus
, respectively. The estimated time to the most recent common ancestor (1.1 million years ago [Mya]) of the MCMVs matches that of their hosts. In conclusion, MCMV has coevolved with these hosts, suggesting that its diversity in nature may be underappreciated, since other members of the subgenus
Mus
likely carry different MCMVs.

IMPORTANCE
Murine cytomegalovirus (MCMV) is a betaherpesvirus of the house mouse,
Mus musculus domesticus
, an important lab model for human cytomegalovirus (HCMV) infection. The majority of lab studies are based on only two strains of MCMVs isolated from
M. m. domesticus
, Smith and K181, the latter derived from repeated passage of Smith in mouse submaxillary glands. The presence of MCMV in other members of the
Mus
subgenus had not even been investigated. By screening mouse samples collected in the European house mouse hybrid zone between
M. m. domesticus
and
M. m. musculus
, we show that MCMV is not restricted to the
M. m. domesticus
subspecies and that MCMVs likely codiverged with their
Mus
hosts. Thus, the diversity of MCMV in nature may be seriously underappreciated, since other members of the subgenus
Mus
likely carry their own MCMV lineages.
Selective Acquisition of Host-Derived ICAM-1 by HIV-1 Is a Matrix-Dependent Process
Authors: Jalaguier Pascal , Cantin Réjean , Maaroufi Halim , Tremblay Michel J. 
Published: October 2014

ABSTRACT

HIV-1 acquires an impressive number of foreign components during its formation. Despite all previous efforts spent studying the nature and functionality of virus-anchored host molecules, the exact mechanism(s) through which such constituents are acquired by HIV-1 is still unknown. However, in the case of ICAM-1, one of the most extensively studied transmembrane proteins found associated with mature virions, the Pr55
Gag
precursor polyprotein appears to be a potential interaction partner. We investigated and characterized at the molecular level the process of ICAM-1 incorporation using initially a Pr55
Gag
-based virus-like particle (VLP) model. Substitution of various domains of Pr55
Gag
, such as the nucleocapsid, SP2, or p6, had no effect on the acquisition of ICAM-1. We found that the structural matrix protein (MA) is mandatory for ICAM-1 incorporation within VLPs, and we confirmed this novel observation with the replication-competent HIV-1 molecular clone NL4.3. Additional studies suggest that the C-terminal two-thirds of MA, and especially 13 amino acids positioned inside the fifth α-helix, are important. Moreover, based on three-dimensional (3D) modeling of protein-protein interactions (i.e., protein-protein docking) and further validation by a virus capture assay, we found that a series of acidic residues in the MA domain interact with basic amino acids located in the ICAM-1 cytoplasmic tail. Our findings provide new insight into the molecular mechanism governing the acquisition of ICAM-1, a host molecule known to enhance HIV-1 infectivity in a significant manner. Altogether, these observations offer a new avenue for the development of antiviral therapeutics that are directed at a target of host origin.

IMPORTANCE
Intercellular adhesion molecule 1 (ICAM-1) is a cell surface host component known to be efficiently inserted within emerging HIV-1 particles. It has been demonstrated that host-derived ICAM-1 molecules act as a strong attachment factor and increase HIV-1 infectivity substantially. Despite previous efforts spent studying virus-associated host molecules, the precise mechanism(s) through which such constituents are inserted within emerging HIV-1 particles still remains obscure. Previous data suggest that the Pr55
Gag
precursor polyprotein appears as a potential interaction partner with ICAM-1. In the present study, we demonstrate that the HIV-1 matrix domain plays a key role in the ICAM-1 incorporation process. Some observations were confirmed with whole-virus preparations amplified in primary human cells, thereby providing physiological significance to our data.
Entry Mechanisms of Herpes Simplex Virus 1 into Murine Epidermis: Involvement of Nectin-1 and Herpesvirus Entry Mediator as Cellular Receptors
Authors: Petermann Philipp , Thier Katharina , Rahn Elena , Rixon Frazer J. , Bloch Wilhelm , Özcelik Semra , Krummenacher Claude , Barron Martin J. , Dixon Michael J. , Scheu Stefanie , Pfeffer Klaus , Knebel-Mörsdorf Dagmar 
Published: October 2014

ABSTRACT

Skin keratinocytes represent a primary entry site for herpes simplex virus 1 (HSV-1)
in vivo
. The cellular proteins nectin-1 and herpesvirus entry mediator (HVEM) act as efficient receptors for both serotypes of HSV and are sufficient for disease development mediated by HSV-2 in mice. How HSV-1 enters skin and whether both nectin-1 and HVEM are involved are not known. We addressed the impact of nectin-1 during entry of HSV-1 into murine epidermis and investigated the putative contribution of HVEM. Using
ex vivo
infection of murine epidermis, we showed that HSV-1 entered the basal keratinocytes of the epidermis very efficiently. In nectin-1-deficient epidermis, entry was strongly reduced. Almost no entry was observed, however, in nectin-1-deficient keratinocytes grown in culture. This observation correlated with the presence of HVEM on the keratinocyte surface in epidermis and with the lack of HVEM expression in nectin-1-deficient primary keratinocytes. Our results suggest that nectin-1 is the primary receptor in epidermis, while HVEM has a more limited role. For primary murine keratinocytes, on which nectin-1 acts as a single receptor, electron microscopy suggested that HSV-1 can enter both by direct fusion with the plasma membrane and via endocytic vesicles. Thus, we concluded that nectin-1 directs internalization into keratinocytes via alternative pathways. In summary, HSV-1 entry into epidermis was shown to strongly depend on the presence of nectin-1, but the restricted presence of HVEM can potentially replace nectin-1 as a receptor, illustrating the flexibility employed by HSV-1 to efficiently invade tissue
in vivo
.

IMPORTANCE
Herpes simplex virus (HSV) can cause a range of diseases in humans, from uncomplicated mucocutaneous lesions to life-threatening infections. The skin is one target tissue of HSV, and the question of how the virus overcomes the protective skin barrier and penetrates into the tissue to reach its receptors is still open. Previous studies analyzing entry into cells grown
in vitro
revealed nectin-1 and HVEM as HSV receptors. To explore the contributions of nectin-1 and HVEM to entry into a natural target tissue, we established an
ex vivo
infection model. Using nectin-1- or HVEM-deficient mice, we demonstrated the distinct involvement of nectin-1 and HVEM for HSV-1 entry into epidermis and characterized the internalization pathways. Such advances in understanding the involvement of receptors in tissue are essential preconditions for unraveling HSV invasion of skin, which in turn will allow the development of antiviral reagents.
Optimization of drug–drug interaction alert rules in a pediatric hospital's electronic health record system using a visual analytics dashboard
Authors: Simpao Allan F , Ahumada Luis M , Desai Bimal R , Bonafide Christopher P , Gálvez Jorge A , Rehman Mohamed A , Jawad Abbas F , Palma Krisha L , Shelov Eric D 
Published: October 2014

AbstractObjective To develop and evaluate an electronic dashboard of hospital-wide electronic health record medication alerts for an alert fatigue reduction quality improvement project.Methods We used visual analytics software to develop the dashboard. We collaborated with the hospital-wide Clinical Decision Support committee to perform three interventions successively deactivating clinically irrelevant drug–drug interaction (DDI) alert rules. We analyzed the impact of the interventions on care providers’ and pharmacists’ alert and override rates using an interrupted time series framework with piecewise regression.Results We evaluated 2 391 880 medication alerts between January 31, 2011 and January 26, 2014. For pharmacists, the median alert rate prior to the first DDI deactivation was 58.74 alerts/100 orders (IQR 54.98–60.48) and 25.11 alerts/100 orders (IQR 23.45–26.57) following the three interventions (p&lt;0.001). For providers, baseline median alert rate prior to the first round of DDI deactivation was 19.73 alerts/100 orders (IQR 18.66–20.24) and 15.11 alerts/100 orders (IQR 14.44–15.49) following the three interventions (p&lt;0.001). In a subgroup analysis, we observed a decrease in pharmacists’ override rates for DDI alerts that were not modified in the system from a median of 93.06 overrides/100 alerts (IQR 91.96–94.33) to 85.68 overrides/100 alerts (IQR 84.29–87.15, p&lt;0.001). The medication serious safety event rate decreased during the study period, and there were no serious safety events reported in association with the deactivated alert rules.Conclusions An alert dashboard facilitated safe rapid-cycle reductions in alert burden that were temporally associated with lower pharmacist override rates in a subgroup of DDIs not directly affected by the interventions; meanwhile, the pharmacists’ frequency of selecting the ‘cancel’ option increased. We hypothesize that reducing the alert burden enabled pharmacists to devote more attention to clinically relevant alerts.
An approach to heavy quarkonium spectra
Authors: Cançelik Y. , Gönül B. 
Published: October 2014

An application of the recently introduced method [M. Çapak et al., J. Math. Phys. 52, 102102 (2011)] to the bound-state eigenvalue problem in the elementary quarkonium potential V(r) = -a/r + br + cr2 is described, proved and illustrated for [Formula: see text] and [Formula: see text] systems. The quasi- and conditionally-exactly solvable spin-averaged mass spectra of heavy quarkonia are obtained in compact forms. The comparison of the present predictions with those of other theories in the related literature, together with the available data, has shown the success of the model used in this work and also revealed that the use of different confinings in the perturbed Coulomb potential descriptions has no considerable effect on the mass spectra of such systems.
Ornamental stones of the Verbano Cusio Ossola quarry district: characterization of materials, quarrying techniques and history and relevance to local and national heritage
Authors: Dino Giovanna A. , Cavallo Alessandro 
Published: October 2014

Abstract
This paper reports the results of an Interreg Project (OSMATER – Sub-Alpine Observatory Materials Territory Restoration) that investigated the present and historical quarrying and processing activities in the cross-border area between the Ossola Valley (Italy) and the Canton Ticino (Switzerland), and the use of dimension stones in local and national architecture. These materials are in many ways unique for their abundance and lithological variety. In the past, their extraction, processing and application characterized in a decisive way the architectural and constructive culture, both in terms of prestigious architecture and civil buildings, establishing a relationship between ‘stones and culture’, and ‘territory and its resources’. In recent years, many traditions of the quarrying, processing and architectural activities are losing importance and interest is being loss, resulting in a loss of knowledge and historical memory. The loss of this knowledge is likely to become irreversible in the short term, with the disappearance of people and social groups as depositaries of tradition. We conclude that the creation of an ‘observatory’, like OSMATER, is desirable and, indeed, essential if we want to preserve the historical memory of the stone industry of an entire production area.
Synthesis, Spectroscopic Characterization, and Biological Evaluation Studies of 5-Bromo-3-(((hydroxy-2-methylquinolin-7-yl)methylene)hydrazono)indolin-2-one and Its Metal (II) Complexes
Authors: Siddappa Kuruba , Mayana Nabiya Sultana 
Published: October 2014

The Schiff base ligand 5-bromo-3-(((8-hydroxy-2-methylquinolin-7-yl)methylene)hydrazono)indolin-2-one (BHMQMHI) was preparedviacondensation of 5-bromo-3-hydrazonoindolin-2-one and 7-formyl-8-hydroxy-2-methylquinoline and its Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II) complexes have been synthesized and characterized by elemental analysis, conductance data, magnetic susceptibility measurements, IR, UV-Vis, mass spectrometry,1H NMR, ESR, XRD, and thermal studies. By these spectral studies it is found that Co(II), Ni(II), and Cu(II) complexes have exhibited octahedral geometry whereas the Zn(II), Cd(II), and Hg(II) complexes have exhibited tetrahedral geometry. Potentiometric studies have been carried out on complexes of Schiff base (BHMQMHI) with Cu(II), Co(II), and Ni(II). Calvin-Bjerrum pH-titration technique as used by Irving and Rossotti has been applied to determine stability constants in mixed solvents at25 ± 1°C. The present study reports the protonation constants of this ligand and stability constants of its metal complexes in dioxane-water (50%, v/v) mixtures. Metal-ligand stability constants fall in the order of Cu(II) > Co(II) > Ni(II) which is in agreement with those reported by Irving stability order. The Schiff base (BHMQMHI) and its metal complexes have been screened for theirin vitroantibacterial and antifungal activities by minimum inhibitory concentration (MIC) method. The DNA cleavage activities of all the complexes were studied by agarose gel electrophoresis method. In addition, the free ligand along with its complexes has been studied for their antioxidant activity.
Targeting JAK1/STAT3 Signaling Suppresses Tumor Progression and Metastasis in a Peritoneal Model of Human Ovarian Cancer
Authors: Wen Wei , Liang Wei , Wu Jun , Kowolik Claudia M. , Buettner Ralf , Scuto Anna , Hsieh Meng-Yin , Hong Hao , Brown Christine E. , Forman Stephen J. , Horne David , Morgan Robert , Wakabayashi Mark , Dellinger Thanh H. , Han Ernest S. , Yim John H. , Jove Richard 
Published: October 2014

AbstractJAK/STAT3 is one of the major signaling pathways that is aberrantly activated in ovarian cancer and associated with tumor progression and poor prognosis in patients with ovarian cancer. In this study, we evaluated the therapeutic potential of targeting JAK/STAT3 signaling in ovarian cancer using a peritoneal dissemination mouse model. We developed this mouse model by injecting a metastatic human ovarian cancer cell line, SKOV3-M-Luc, into the peritoneal cavity of immunodeficient mice. This model displayed a phenotype similar to late-stage ovarian cancer, including extensive peritoneal metastasis and ascites production. The constitutive activation of STAT3 in human ovarian cancer cells appeared to be mediated by an autocrine cytokine loop involving the IL6 family of cytokines and JAK1 kinase. shRNA-mediated knockdown of JAK1 or STAT3 in ovarian cancer cells led to reduced tumor growth, decreased peritoneal dissemination, and diminished ascites production, suggesting a critical role of STAT3 in ovarian cancer progression. Similar results were obtained when a small-molecule inhibitor (JAKi) of the JAK1 kinase was used to treat ovarian cancer in this model. In addition, we found that the expression level of IL6 was correlated with activation of STAT3 in ovarian cancer cells both in vitro and in vivo, suggesting a potential application of IL6 as a biomarker. Altogether, our results demonstrate that targeting JAK1/STAT3, using shRNA knockdown or a small-molecule inhibitor, effectively suppressed ovarian tumor progression and, therefore, could be a potential novel therapeutic approach for treating advanced ovarian cancer. Mol Cancer Ther; 13(12); 3037–48. ©2014 AACR.