bluuebunny/crossref_metadata_2025_split huggingface dataset:
High temperature causes negative whole‐plant carbon balance under mild drought
Authors: Zhao Junbin , Hartmann Henrik , Trumbore Susan , Ziegler Waldemar , Zhang Yiping 
Published: July 2013

Summary

Theoretically, progressive drought can force trees into negative carbon (C) balance by reducing stomatal conductance to prevent water loss, which also decreases C assimilation. At higher temperatures, negative C balance should be initiated at higher soil moisture because of increased respiratory demand and earlier stomatal closure. Few data are available on how these theoretical relationships integrate over the whole plant.

We exposed Thuja occidentalis to progressive drought under three temperature conditions (15, 25, and 35°C), and measured C and water fluxes using a whole‐tree chamber design.

High transpiration rates at higher temperatures led to a rapid decline in soil moisture. During the progressive drought, soil moisture‐driven changes in photosynthesis had a greater impact on the whole‐plant C balance than respiration. The soil moisture content at which whole‐plant C balance became negative increased with temperature, mainly as a result of higher respiration rates and an earlier onset of stomatal closure under a warmer condition.

Our results suggest that the effect of drought on whole‐plant C balance is highly temperature‐dependent. High temperature causes a negative C balance even under mild drought and may increase the risk of C starvation.
Cardiac Device Complications in the Cognitively Impaired
Authors: JAMA ABDI , RABINSTEIN ALEJANDRO , HODGE DAVID , HERGES REGINA , ASIRVATHAM SAMUEL , CHA YONG‐MEI , POWELL BRIAN , REA ROBERT F. , FRIEDMAN PAUL 
Published: July 2013

BackgroundPatients with preexisting mild cognitive impairment or dementia may be at increased risk for developing cardiac device complications due to an impaired ability to follow postimplant care instructions. We sought to determine whether rates of infection, lead dislodgement, or appropriate or inappropriate implantable cardioverter defibrillator (ICD) shocks are increased in this population.MethodsMedical charts of 561 patients with mild cognitive impairment or dementia who underwent pacemaker (PM) or ICD implantation between January 2002 and October 2009 at Mayo Clinic were identified. A total of 134 patients who were diagnosed with cognitive impairment or dementia before device implantation or within 1 year of implantation were compared with 134 matched controls. Information was collected on patient characteristics, comorbid medical conditions, ejection fraction, complications, device type, device therapy, and mortality. Device information was prospectively entered into a database and retrospectively reviewed.ResultsOf the 134 patients with mild cognitive impairment and dementia, 99 underwent PM implantation and 35 underwent ICD implantation. Compared to controls, there was no difference in patient characteristics, ejection fraction, or comorbidities except for diabetes, which was more prevalent in the cognitively impaired and demented group (18.7% vs 30.6%, P = 0.02). There was no difference in device therapy and complications (14.4% vs 5.8%, P = 0.268). However, there was a decreased survival in patients with cognitive impairment and dementia when compared to the control group (42% vs 67% at 5 years, P = 0.007).ConclusionPatients with cognitive impairment and standard device indications are not at increased risk for device complications and therapy but their survival is much lower than in matched controls. The cause of this lower survival is unknown but may be related to the underlying neurological disease. Presence of cognitive impairment should therefore be considered when contemplating implantation of a cardiac device.
Assessing the susceptibility of alpine soils to erosion using soil physical and site indicators
Authors: Stanchi S. , Freppaz M. , Godone D. , Zanini E. 
Published: July 2013

AbstractSoil erosion in mountainous regions is a key issue in land use planning, and this is particularly true in the Alps where intense anthropogenic influences at low elevations and abandonment in higher regions often coexist to affect soils. Natural hazard and risk assessment are essential given the density of settlements and associated facilities. Soil loss due to water erosion is very common and is becoming more frequent as a consequence of climate change which affects precipitation regimes, frequency of extreme meteorological events, snow melt and vegetation. In this study, we describe the production of a map showing susceptibility to soil erosion in the Aosta Valley (northwest Italian Alps). Most research on slope instability has focused on rock failures, but we investigated upper soil horizons by analysing chemical and physical properties, which could contribute to slope instability. The steps involved in creating the map are explained, and these involved GIS overlay, sampling, soil description, selection of relevant chemical and physical indicators of soil susceptibility to erosion, and overall erosion susceptibility assessment. The resultant indicator values correspond well with field observations to thus validate the methodology and demonstrate its usefulness in land use planning and management in Alpine areas.
Mitogen-Activated Protein Kinase Phosphatase 1 Disrupts Proinflammatory Protein Synthesis in Endotoxin-Adapted Monocytes
Authors: Brudecki Laura , Ferguson Donald A. , McCall Charles E. , El Gazzar Mohamed 
Published: July 2013

ABSTRACT
Autotoxic production of proinflammatory mediators during early sepsis induces excessive inflammation, and their later suppression may limit the immune response. We previously reported that sepsis differentially represses transcription and translation of tumor necrosis factor alpha (TNF-α) and interleukin 1β (IL-1β) to reprogram sepsis inflammation. This switch is gene specific and plays a crucial role in the clinically relevant syndrome of endotoxin adaptation/tolerance, multiorgan failure, and poor sepsis outcome. To further define the mechanisms responsible for translation disruption that follows inflammation induction, we used THP-1 human promonocytes as a model of Toll-like receptor 4 (TLR4) responses found in sepsis. We showed that phosphorylation-dependent activation of p38 mitogen-activated protein kinase (MAPK) and translation disruption of TNF-α and IL-6 follow increased MAPK phosphatase 1 (MKP-1) expression and that MKP-1 knockdown rephosphorylates p38 and restores the capacity to translate TNF-α and IL-6 mRNAs. We also observed that the RNA-binding protein motif 4 (RBM4), a p38 MAPK target, accumulates in an unphosphorylated form in the cytosol in endotoxin-adapted cells, suggesting that dephosphorylated RBM4 may function as a translational repressor. Moreover, MKP-1 knockdown promotes RBM4 phosphorylation, blocks its transfer from the nucleus to the cytosol, and reverses translation repression. We also found that microRNA 146a (miR-146a) knockdown prevents and miR-146a transfection induces MKP-1 expression, which lead to increases or decreases in TNF-α and IL-6 translation, respectively. We conclude that a TLR4-, miR-146a-, p38 MAPK-, and MKP-1-dependent autoregulatory pathway regulates the translation of proinflammatory genes during the acute inflammatory response by spatially and temporally modifying the phosphorylation state of RBM4 translational repressor protein.
Cks1 Enhances Transcription Efficiency at the
GAL1
Locus by Linking the Paf1 Complex to the 19S Proteasome
Authors: Pan Yen-Ru , Sun Michael , Wohlschlegel James , Reed Steven I. 
Published: July 2013

ABSTRACT

Cks1 was originally identified based on genetic interactions with
CDC28
, the gene that encodes Cdk1 in the budding yeast
Saccharomyces cerevisiae
. Subsequent work has shown that Cks1 binds Cdc28 and modulates its activity against certain substrates. However, the Cks1/Cdc28 complex also has a role in transcriptional chromatin remodeling not related to kinase activity. In order to elucidate protein networks associated with Cks1 transcriptional functions, proteomic analysis was performed on immunoaffinity-purified Cks1, identifying a physical interaction with the Paf1 complex. Specifically, we found that the Paf1 complex component Rtf1 interacts directly with Cks1 and that this interaction is essential for efficient recruitment of Cks1 to chromatin in the context of
GAL1
gene induction. We further found that Cks1 in this capacity serves as an adaptor allowing Rtf1 to recruit 19S proteasome particles, shown to be required for efficient RNA production from some rapidly inducible genes such as
GAL1
.
A Literature Review of Laboratory-Acquired Brucellosis
Authors: Traxler Rita M. , Lehman Mark W. , Bosserman Elizabeth A. , Guerra Marta A. , Smith Theresa L. 
Published: July 2013

ABSTRACTBrucellosis is a bacterial zoonotic disease which has been associated with laboratory-acquired infections. No recent reviews have addressed the characteristics of laboratory-acquired brucellosis (LAB). English-language literature was reviewed to identify reports of laboratory exposures toBrucellaspp. and LAB cases between 1982 and 2007. Evaluation of 28 case reports identified 167 potentially exposed laboratory workers, of whom 71 had LAB. Nine reports were identified that summarized an additional 186 cases of LAB. Only 18 (11%) exposures were due to laboratory accidents, 147 (88%) exposures were due to aerosolization of organisms during routine identification activities, and the circumstances of 2 (1%) exposures were unknown.Brucella melitensiswas the causative agent in 80% (135/167) of the exposures. Workers with high-risk exposures were 9.3 times more likely to develop LAB than workers with low-risk exposures (95% confidence interval [CI], 3.0 to 38.6;P< 0.0001); they were also 0.009 times likelier to develop LAB if they took antimicrobial PEP than if they did not (95% CI, 0 to 0.042;P< 0.0001). The median incubation period in case and summary reports was 8 weeks (range 1 to 40 weeks). Antimicrobial PEP is effective in preventing LAB. The incubation period may be used to identify appropriate serological and symptom surveillance time frames for exposed laboratory workers.
Review of Brucellosis Cases from Laboratory Exposures in the United States in 2008 to 2011 and Improved Strategies for Disease Prevention
Authors: Traxler R. M. , Guerra M. A. , Morrow M. G. , Haupt T. , Morrison J. , Saah J. R. , Smith C. G. , Williams C. , Fleischauer A. T. , Lee P. A. , Stanek D. , Trevino-Garrison I. , Franklin P. , Oakes P. , Hand S. , Shadomy S. V. , Blaney D. D. , Lehman M. W. , Benoit T. J. , Stoddard R. A. , Tiller R. V. , De B. K. , Bower W. , Smith T. L. 
Published: July 2013

ABSTRACT
Five laboratory-acquired brucellosis (LAB) cases that occurred in the United States between 2008 and 2011 are presented. The Centers for Disease Control and Prevention (CDC) reviewed the recommendations published in 2008 and the published literature to identify strategies to further prevent LAB. The improved prevention strategies are described.
Flaviviruses Are Sensitive to Inhibition of Thymidine Synthesis Pathways
Authors: Fischer Matthew A. , Smith Jessica L. , Shum David , Stein David A. , Parkins Christopher , Bhinder Bhavneet , Radu Constantin , Hirsch Alec J. , Djaballah Hakim , Nelson Jay A. , Früh Klaus 
Published: July 2013

ABSTRACT
Dengue virus has emerged as a global health threat to over one-third of humankind. As a positive-strand RNA virus, dengue virus relies on the host cell metabolism for its translation, replication, and egress. Therefore, a better understanding of the host cell metabolic pathways required for dengue virus infection offers the opportunity to develop new approaches for therapeutic intervention. In a recently described screen of known drugs and bioactive molecules, we observed that methotrexate and floxuridine inhibited dengue virus infections at low micromolar concentrations. Here, we demonstrate that all serotypes of dengue virus, as well as West Nile virus, are highly sensitive to both methotrexate and floxuridine, whereas other RNA viruses (Sindbis virus and vesicular stomatitis virus) are not. Interestingly, flavivirus replication was restored by folinic acid, a thymidine precursor, in the presence of methotrexate and by thymidine in the presence of floxuridine, suggesting an unexpected role for thymidine in flavivirus replication. Since thymidine is not incorporated into RNA genomes, it is likely that increased thymidine production is indirectly involved in flavivirus replication. A possible mechanism is suggested by the finding that p53 inhibition restored dengue virus replication in the presence of floxuridine, consistent with thymidine-less stress triggering p53-mediated antiflavivirus effects in infected cells. Our data reveal thymidine synthesis pathways as new and unexpected therapeutic targets for antiflaviviral drug development.
CD8
+
T-Cell Epitope Mapping for Pneumonia Virus of Mice in H-2
b
Mice
Authors: Walsh Kevin B. , Sidney John , Welch Megan , Fremgen Daniel M. , Sette Alessandro , Oldstone Michael B. A. 
Published: July 2013

ABSTRACT

The paramyxovirus pneumonia virus of mice (PVM) is a rodent model of human respiratory syncytial virus (hRSV) pathogenesis. Here we characterized the PVM-specific CD8
+
T-cell repertoire in susceptible C57BL/6 mice. In total, 15 PVM-specific CD8
+
T-cell epitopes restricted by H-2D
b
and/or H-2K
b
were identified. These data open the door for using widely profiled, genetically manipulated C57BL/6 mice to study the contribution of epitope-specific CD8
+
T cells to PVM pathogenesis.
Epstein-Barr Virus-Encoded BARF1 Promotes Proliferation of Gastric Carcinoma Cells through Regulation of NF-κB
Authors: Chang Mee Soo , Kim Dong Ha , Roh Jin Kyung , Middeldorp Jaap M. , Kim Yang Soo , Kim Sunghan , Han Seungbong , Kim Chul Woo , Lee Byung Lan , Kim Woo Ho , Woo Jun Hee 
Published: July 2013

ABSTRACT

In Epstein-Barr virus (EBV)-infected gastric carcinoma, EBV-encoded BARF1 has been hypothesized to function as an oncogene. To evaluate cellular changes induced by BARF1, we isolated the full-length
BARF1
gene from gastric carcinoma cells that were naturally infected with EBV and transfected
BARF1
into EBV-negative gastric carcinoma cells. BARF1 protein was primarily secreted into culture supernatant and only marginally detectable within cells. Compared with gastric carcinoma cells containing empty vector, BARF1-expressing gastric carcinoma cells exhibited increased cell proliferation (
P
< 0.05). There were no significant differences in apoptosis, invasion, or migration between BARF1-expressing gastric carcinoma cells and empty vector-transfected cells. BARF1-expressing gastric carcinoma cells demonstrated increased nuclear expression of nuclear factor kappa B (NF-κB) RelA protein and increased NF-κB-dependent cyclin D1. The expression of p21
WAF1
was diminished by BARF1 transfection and increased by NF-κB inhibition. Proliferation of naturally EBV-infected gastric carcinoma cells was suppressed by BARF1 small interfering RNA (siRNA) (
P
< 0.05). Immunohistochemical analysis of 120 human gastric carcinoma tissues demonstrated increased expression of cyclin D1 and reduced expression of p21
WAF1
in EBV-positive samples versus EBV-negative gastric carcinomas (
P
< 0.05). In conclusion, the secreted BARF1 may stimulate proliferation of EBV-infected gastric carcinoma cells via upregulation of NF-κB/cyclin D1 and reduction of the cell cycle inhibitor p21
WAF1
, thereby facilitating EBV-induced cancer progression.
High Production Rates Sustain
In Vivo
Levels of PD-1
high
Simian Immunodeficiency Virus-Specific CD8 T Cells in the Face of Rapid Clearance
Authors: Petrovas Constantinos , Yamamoto Takuya , Price David A. , Rao Srinivas S. , Klatt Nichole R. , Brenchley Jason M. , Douek Daniel C. , Gostick Emma , Angermann Bastian R. , Grossman Zvi , Macallan Derek C. , Meier-Schellersheim Martin , Koup Richard A. 
Published: July 2013

ABSTRACT

Programmed Death 1 (PD-1) expression by human/simian immunodeficiency virus (HIV/SIV)-specific CD8 T cells has been associated with defective cytokine production and reduced
in vitro
proliferation capacity. However, the cellular mechanisms that sustain PD-1
high
virus-specific CD8 T cell responses during chronic infection are unknown. Here, we show that the PD-1
high
phenotype is associated with accelerated
in vivo
CD8 T cell turnover in SIV-infected rhesus macaques, especially within the SIV-specific CD8 T cell pool. Mathematical modeling of 5-bromo-2′ deoxyuridine (BrdU) labeling dynamics demonstrated a significantly increased generation rate of PD-1
high
compared to PD-1
low
CD8 T cells in all memory compartments. Simultaneous analysis of Ki67 and BrdU kinetics revealed a complex
in vivo
turnover profile whereby only a small fraction of PD-1
high
cells, but virtually all PD-1
low
cells, returned to rest after activation. Similar kinetics operated in both chronic and acute SIV infection. Our data suggest that the persistence of PD-1
high
SIV-specific CD8 T cells in chronic infection is maintained
in vivo
by a mechanism involving high production coupled with a high disappearance rate.
Efficacy in Pigs of Inactivated and Live Attenuated Influenza Virus Vaccines against Infection and Transmission of an Emerging H3N2 Similar to the 2011-2012 H3N2v
Authors: Loving Crystal L. , Lager Kelly M. , Vincent Amy L. , Brockmeier Susan L. , Gauger Phillip C. , Anderson Tavis K. , Kitikoon Pravina , Perez Daniel R. , Kehrli Marcus E. 
Published: July 2013

ABSTRACT
Vaccines provide a primary means to limit disease but may not be effective at blocking infection and pathogen transmission. The objective of the present study was to evaluate the efficacy of commercial inactivated swine influenza A virus (IAV) vaccines and experimental live attenuated influenza virus (LAIV) vaccines against infection with H3N2 virus and subsequent indirect transmission to naive pigs. The H3N2 virus evaluated was similar to the H3N2v detected in humans during 2011-2012, which was associated with swine contact at agricultural fairs. One commercial vaccine provided partial protection measured by reduced nasal shedding; however, indirect contacts became infected, indicating that the reduction in nasal shedding did not prevent aerosol transmission. One LAIV vaccine provided complete protection, and none of the indirect-contact pigs became infected. Clinical disease was not observed in any group, including nonvaccinated animals, a consistent observation in pigs infected with contemporary reassortant H3N2 swine viruses. Serum hemagglutination inhibition antibody titers against the challenge virus were not predictive of efficacy; titers following vaccination with a LAIV that provided sterilizing immunity were below the level considered protective, yet titers in a commercial vaccine group that was not protected were above that level. While vaccination with currently approved commercial inactivated products did not fully prevent transmission, certain vaccines may provide a benefit by limitating shedding, transmission, and zoonotic spillover of antigenically similar H3N2 viruses at agriculture fairs when administered appropriately and used in conjunction with additional control measures.
Structural Characterization of Cleaved, Soluble HIV-1 Envelope Glycoprotein Trimers
Authors: Khayat Reza , Lee Jeong Hyun , Julien Jean-Philippe , Cupo Albert , Klasse Per Johan , Sanders Rogier W. , Moore John P. , Wilson Ian A. , Ward Andrew B. 
Published: July 2013

ABSTRACT

Human immunodeficiency virus type 1 (HIV-1) infection is a significant global public health problem for which development of an effective prophylactic vaccine remains a high scientific priority. Many concepts for a vaccine are focused on induction of appropriate titers of broadly neutralizing antibodies (bNAbs) against the viral envelope (Env) glycoproteins gp120 and gp41, but no immunogen has yet accomplished this goal in animals or humans. One approach to induction of bNAbs is to design soluble, trimeric mimics of the native viral Env trimer. Here, we describe structural studies by negative-stain electron microscopy of several variants of soluble Env trimers based on the KNH1144 subtype A sequence. These Env trimers are fully cleaved between the gp120 and gp41 components and stabilized by specific amino acid substitutions. We also illustrate the structural consequences of deletion of the V1/V2 and V3 variable loops from gp120 and the membrane-proximal external region (MPER) from gp41. All of these variants adopt a trimeric configuration that appropriately mimics native Env spikes, including the CD4 receptor-binding site and the epitope for the VRC PG04 bNAb. These cleaved, soluble trimer designs can be adapted for use with multiple different
env
genes for both vaccine and structural studies.
Identification of a Novel Subgroup of Koala Retrovirus from Koalas in Japanese Zoos
Authors: Shojima Takayuki , Yoshikawa Rokusuke , Hoshino Shigeki , Shimode Sayumi , Nakagawa So , Ohata Takuji , Nakaoka Rie , Miyazawa Takayuki 
Published: July 2013

ABSTRACT
We identified a new subgroup of koala retrovirus (KoRV), named KoRV-J, which utilizes thiamine transport protein 1 as a receptor instead of the Pit-1 receptor used by KoRV (KoRV-A). By subgroup-specific PCR, KoRV-J and KoRV-A were detected in 67.5 and 100% of koalas originating from koalas from northern Australia, respectively. Altogether, our results indicate that the invasion of the koala population by KoRV-J may have occurred more recently than invasion by KoRV-A.
Heterologous Viral Promoters Incorporated into the Human Cytomegalovirus Genome Are Silenced during Experimental Latency
Authors: Qin Qingsong , Penkert Rhiannon R. , Kalejta Robert F. 
Published: July 2013

ABSTRACT

Human cytomegalovirus (HCMV) lytic phase gene expression is repressed upon entry into myeloid lineage cells where the virus establishes latency. Lytic infection is not initiated because the tegument-delivered transactivator protein pp71 fails to enter the nucleus and inactivate the Daxx-mediated cellular intrinsic defense that silences the viral genome. When pp71 is expressed
de novo
in THP-1 monocytes, it localizes to the nucleus, inactivates the Daxx defense, and initiates lytic infection. We speculated that replacing the native viral promoter that drives pp71 expression with one that is highly and constitutively active in myeloid cells would permit pp71
de novo
expression upon infection and that this newly expressed pp71 would accumulate in the nucleus, inactivate the intrinsic defense, and initiate the cascade of lytic gene expression. Surprisingly, we found that this promoter was still subject to normal silencing mechanisms in THP-1 monocytes and primary CD34
+
cells, two independent myeloid lineage cells. A second constitutively active heterologous viral promoter located in a different region of the HCMV genome was also silenced in THP-1 and CD34
+
cells. Furthermore, these two independent heterologous viral promoters inserted into three different regions of the HCMV genome in three different viral strains all required prior expression of the viral immediate early proteins for activation in fibroblasts. From this, we conclude that incorporation within the HCMV genome impacts the proclivity of heterologous viral promoters to initiate transcription. These observations have mechanistic implications for the expression of viral genes and transgenes during both lytic infection and latency.