bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reassessment of the Role of Aromatic Amino Acid Hydroxylases and the Effect of Infection by Toxoplasma gondii on Host Dopamine
Authors: Wang Zi T. , Harmon Steve , O'Malley Karen L. , Sibley L. David 
Published: December 2014

ABSTRACTToxoplasma gondiiinfection has been described previously to cause infected mice to lose their fear of cat urine. This behavioral manipulation has been proposed to involve alterations of host dopamine pathways due to parasite-encoded aromatic amino acid hydroxylases. Here, we report successful knockout and complementation of the aromatic amino acid hydroxylaseAAH2gene, with no observable phenotype in parasite growth or differentiationin vitroandin vivo. Additionally, expression levels of the two aromatic amino acid hydroxylases were negligible both in tachyzoites and in bradyzoites. Finally, we were unable to confirm previously described effects of parasite infection on host dopamine eitherin vitroorin vivo, even whenAAH2was overexpressed using theBAG1promoter. Together, these data indicate that AAH enzymes in the parasite do not cause global or regional alterations of dopamine in the host brain, although they may affect this pathway locally. Additionally, our findings suggest alternative roles for theAHHenzymes inT. gondii, sinceAAH1is essential for growth in nondopaminergic cells.
CX
3
CR1 Is Dispensable for Control of Mucosal Candida albicans Infections in Mice and Humans
Authors: Break Timothy J. , Jaeger Martin , Solis Norma V. , Filler Scott G. , Rodriguez Carlos A. , Lim Jean K. , Lee Chyi-Chia Richard , Sobel Jack D. , Netea Mihai G. , Lionakis Michail S. 
Published: December 2014

ABSTRACT

Candida albicans
is part of the normal commensal microbiota of mucosal surfaces in a large percentage of the human population. However, perturbations of the host's immune response or bacterial microbiota have been shown to predispose individuals to the development of opportunistic
Candida
infections. It was recently discovered that a defect in the chemokine receptor CX
3
CR1 increases susceptibility of mice and humans to systemic candidiasis. However, whether CX
3
CR1 confers protection against mucosal
C. albicans
infection has not been investigated. Using two different mouse models, we found that Cx3cr1 is dispensable for the induction of interleukin 17A (IL-17A), IL-22, and IL-23 in the tongue after infection, as well as for the clearance of mucosal candidiasis from the tongue or lower gastrointestinal (GI) tract colonization. Furthermore, the dysfunctional human CX
3
CR1 allele

CX
3
CR1-M280

was not associated with development of recurrent vulvovaginal candidiasis (RVVC) in women. Taken together, these data indicate that CX
3
CR1 is not essential for protection of the host against mucosal candidiasis, underscoring the dependence on different mammalian immune factors for control of mucosal versus systemic
Candida
infections.
Identification of Host Proteins Involved in Rickettsial Invasion of Tick Cells
Authors: Petchampai Natthida , Sunyakumthorn Piyanate , Banajee Kaikhushroo H. , Verhoeve Victoria I. , Kearney Michael T. , Macaluso Kevin R. 
Published: December 2014

ABSTRACT

Tick-borne spotted fever group (SFG)
Rickettsia
species are obligate intracellular bacteria capable of infecting both vertebrate and invertebrate host cells, an essential process for subsequent bacterial survival in distinct hosts. The host cell signaling molecules involved in the uptake of
Rickettsia
into mammalian and
Drosophila
cells have been identified; however, invasion into tick cells is understudied. Considering the movement of SFG
Rickettsia
between vertebrate and invertebrate hosts, the hypothesis is that conserved mechanisms are utilized for host cell invasion. The current study employed biochemical inhibition assays to determine the tick proteins involved in
Rickettsia montanensis
infection of tick-derived cells from a natural host,
Dermacentor variabilis
. The results revealed several tick proteins important for rickettsial invasion, including actin filaments, actin-related protein 2/3 complex, phosphatidylinositol-3′-kinase, protein tyrosine kinases (PTKs), Src family PTK, focal adhesion kinase, Rho GTPase Rac1, and neural Wiskott-Aldrich syndrome protein. Delineating the molecular mechanisms of rickettsial infection is critical to a thorough understanding of rickettsial transmission in tick populations and the ecology of tick-borne rickettsial diseases.
New Role for Human α-Defensin 5 in the Fight against Hypervirulent Clostridium difficile Strains
Authors: Furci Lucinda , Baldan Rossella , Bianchini Valentina , Trovato Alberto , Ossi Cristina , Cichero Paola , Cirillo Daniela M. 
Published: December 2014

ABSTRACT

Clostridium difficile
infection (CDI), one of the most common hospital-acquired infections, is increasing in incidence and severity with the emergence and diffusion of hypervirulent strains. CDI is precipitated by antibiotic treatment that destroys the equilibrium of the gut microbiota. Human α-defensin 5 (HD5), the most abundant enteric antimicrobial peptide, is a key regulator of gut microbiota homeostasis, yet it is still unknown if
C. difficile
, which successfully evades killing by other host microbicidal peptides, is susceptible to HD5. We evaluated, by means of viability assay, fluorescence-activated cell sorter (FACS) analysis, and electron microscopy, the antimicrobial activities of α-defensins 1 and 5 against a panel of
C. difficile
strains encompassing the most prevalent epidemic and hypervirulent PCR ribotypes in Europe (012, 014/020, 106, 018, 027, and 078). Here we show that (i) concentrations of HD5 within the intestinal physiological range produced massive
C. difficile
cell killing; (ii) HD5 bactericidal activity was mediated by membrane depolarization and bacterial fragmentation with a pattern of damage peculiar to
C. difficile
bacilli, compared to commensals like
Escherichia coli
and
Enterococcus faecalis
; and (iii) unexpectedly, hypervirulent ribotypes were among the most susceptible to both defensins. These results support the notion that HD5, naturally present at very high concentrations in the mucosa of the small intestine, could indeed control the very early steps of CDI by killing
C. difficile
bacilli at their germination site. As a consequence, HD5 can be regarded as a good candidate for the containment of hypervirulent
C. difficile
strains, and it could be exploited in the therapy of CDI and relapsing
C. difficile
-associated disease.
Nuclease Activity of Legionella pneumophila Cas2 Promotes Intracellular Infection of Amoebal Host Cells
Authors: Gunderson Felizza F. , Mallama Celeste A. , Fairbairn Stephanie G. , Cianciotto Nicholas P. 
Published: December 2014

ABSTRACT

Legionella pneumophila
, the primary agent of Legionnaires' disease, flourishes in both natural and man-made environments by growing in a wide variety of aquatic amoebae. Recently, we determined that the Cas2 protein of
L. pneumophila
promotes intracellular infection of
Acanthamoeba castellanii
and
Hartmannella vermiformis
, the two amoebae most commonly linked to cases of disease. The Cas2 family of proteins is best known for its role in the bacterial and archeal clustered regularly interspaced short palindromic repeat (CRISPR)–CRISPR-associated protein (Cas) system that constitutes a form of adaptive immunity against phage and plasmid. However, the infection event mediated by
L. pneumophila
Cas2 appeared to be distinct from this function, because
cas2
mutants exhibited infectivity defects in the absence of added phage or plasmid and since mutants lacking the CRISPR array or any one of the other
cas
genes were not impaired in infection ability. We now report that the Cas2 protein of
L. pneumophila
has both RNase and DNase activities, with the RNase activity being more pronounced. By characterizing a catalytically deficient version of Cas2, we determined that nuclease activity is critical for promoting infection of amoebae. Also, introduction of Cas2, but not its catalytic mutant form, into a strain of
L. pneumophila
that naturally lacks a CRISPR-Cas locus caused that strain to be 40- to 80-fold more infective for amoebae, unequivocally demonstrating that Cas2 facilitates the infection process independently of any other component encoded within the CRISPR-Cas locus. Finally, a
cas2
mutant was impaired for infection of
Willaertia magna
but not
Naegleria lovaniensis
, suggesting that Cas2 promotes infection of most but not all amoebal hosts.
Cj1386, an Atypical Hemin-Binding Protein, Mediates Hemin Trafficking to KatA in Campylobacter jejuni
Authors: Flint Annika , Stintzi Alain 
Published: December 2014

ABSTRACT

Catalase enzymes detoxify H
2
O
2
by the dismutation of H
2
O
2
into O
2
and H
2
O through the use of hemin cofactors. While the structure and biochemical properties of catalase enzymes have been well characterized over many decades of research, it remained unclear how catalases acquire hemin. We have previously reported that Cj1386 is essential for ensuring proper hemin content in
Campylobacter jejuni
catalase (KatA) (A. Flint, Y. Q. Sun, and A. Stintzi, J Bacteriol
194:
334–345, 2012). In this report, an in-depth molecular characterization of Cj1386 was performed to elucidate the mechanistic details of this association. Coimmunoprecipitation assays revealed that KatA-Cj1386 transiently interact
in vivo
, and UV-visible spectroscopy demonstrated that purified Cj1386 protein binds hemin. Furthermore, hemin titration experiments determined that hemin binds to Cj1386 in a 1:1 ratio with hexacoordinate hemin binding. Mutagenesis of potential hemin-coordinating residues in Cj1386 showed that tyrosine 57 was essential for hemin coordination when Cj1386 was overexpressed in
Escherichia coli
. The importance of tyrosine 57 in hemin trafficking
in vivo
was confirmed by introducing the
cj1386

Y57A

allele into a
C. jejuni
Δ
cj1386
mutant background. The
cj1386

Y57A

mutation resulted in increased sensitivity toward H
2
O
2
relative to the wild type, suggesting that KatA was not functional in this strain. In support of this finding, KatA immunoprecipitated from the Δ
cj1386+cj1386

Y57A

mutant had significantly reduced hemin content compared to that of the
cj1386

WT

background. Overall, these findings indicate that Cj1386 is involved in directly trafficking hemin to KatA and that tyrosine 57 plays a key role in this function.
A Serum MicroRNA Signature Predicts Tumor Relapse and Survival in Triple-Negative Breast Cancer Patients
Authors: Kleivi Sahlberg Kristine , Bottai Giulia , Naume Bjørn , Burwinkel Barbara , Calin George A. , Børresen-Dale Anne-Lise , Santarpia Libero 
Published: December 2014

Abstract
Purpose: Triple-negative breast cancers (TNBC) are associated with high risk of early tumor recurrence and poor outcome. Common prognostic biomarkers give very restricted predictive information of tumor recurrences in TNBC. Human serum contains stably expressed microRNAs (miRNAs), which have been discovered to predict prognosis in patients with cancer. The purpose of this study was to identify circulating biomarkers able to predict clinical outcome in TNBC.
Experimental Design: We performed genome-wide serum miRNA expression and real-time PCR analyses to investigate the ability of miRNAs in predicting tumor relapse in serum samples from 60 primary TNBC. Patients were divided into training and testing cohorts.
Results: By Cox regression analysis, we identified a four-miRNA signature (miR-18b, miR-103, miR-107, and miR-652) that predicted tumor relapse and overall survival. This miRNA signature was further validated in an independent cohort of 70 TNBC. A high-risk signature score was developed and significantly associated with tumor recurrence and reduced survival. Multivariate Cox regression models indicated that the risk score based on the four-miRNA signature was an independent prognostic classifier of patients with TNBC.
Conclusions: This signature may serve as a minimally invasive predictor of tumor relapse and overall survival for patients with TNBC. This prediction model may ultimately lead to better treatment options for patients with TNBC. Clin Cancer Res; 21(5); 1207–14. ©2014 AACR.
Lichens from the Utsteinen Nunatak (Sør Rondane Mountains, Antarctica), with the description of one new species and the establishment of permanent plots
Authors: Ertz Damien , Aptroot André , Van de Vijver Bart , Sliwa Lucyna , Moermans Coraline , Øvstedal Dag 
Published: December 2014

In order to establish baseline environmental conditions at the Utsteinen Nunatak (Sør Rondane Mountains, Antarctica) chosen for the installation of the new Belgian Antarctic research station, a detailed survey of the different lichen species was performed in 2007. The establishment of permanent plots will allow the accurate monitoring of possible future impacts of human activities on the biodiversity and, on a long-term scale, to detect future climate changes. A complete survey of the lichen species was made for each of the 23 permanent plots of the Utsteinen Ridge. The abundance of each species within each plot was also evaluated. Exhaustive lists of lichens were also completed for other parts of the Utsteinen Nunatak. Additionally, historic collections from the same area were revised. A total of twenty-three lichen species and two lichenicolous fungi was detected in the recent samples whereas the historic material yielded three additional species. These results raise the total number of known taxa for the Sør Rondane Mountains from ten to 28, despite the small area investigated. Trapelia antarctica is described as new to science. Buellia bastini is synonymized with Buellia nelsonii and Lecidea autenboeri is synonymized with Carbonea vorticosa. The lichen flora of Utsteinen is made of a high percentage (48%) of Antarctic endemics. Lichens were abundantly present on the Utsteinen Ridge. The numbers of species per plot varied from one to 18 with an average of ten. The detailed grid map for the Utsteinen Ridge will be useful in monitoring future changes in lichen population and diversity. Five plots presented the richest lichen flora and need therefore careful protection against any future human activities.
Retrieving Cloud Ice Water Content Using Millimeter- and Centimeter-Wavelength Radar Polarimetric Observables
Authors: Lu Yinghui , Aydin Kültegin , Clothiaux Eugene E. , Verlinde Johannes 
Published: December 2014

AbstractScattering properties of a large collection of pristine ice crystals at millimeter and centimeter wavelengths are calculated using the generalized multiparticle Mie method. Millimeter- and centimeter-wavelength radar observables are also calculated by employing particle size distributions (PSDs) that ensure the bulk properties (e.g., ice water content and total number concentration) fall within physically realistic ranges. The relationships between radar reflectivity Z and ice water content (IWC) are shown to be sensitive (from one to two orders of magnitude in variability) to the PSDs used and are thus not recommended for IWC retrievals. The relationships between IWC and specific differential phase KDP are less dependent on PSDs. Simple relationships between IWC and KDP at different radar elevation angles and wavelengths are given. If only the general crystal type is known (i.e., planar vs columnar), IWC retrieval errors based on KDP mostly fall within 30%. If more detailed ice crystal type is known, the retrieval errors are reduced to mostly within 10%. These results are similar to earlier reports in the literature but are based on a more extensive collection of model ice crystals and electromagnetic-scattering computations at four wavelengths: X, Ku, Ka, and W bands. The applicability of KDP in retrieving IWC is limited by the measurement accuracy of KDP, which usually requires averaging over several kilometers in range. Given the same noise level, the shorter wavelengths may have relatively smaller fractional errors than the longer wavelengths in KDP-based IWC retrievals and are promising wavelengths for further investigation.
On the Shoaling of Solitary Waves in the Presence of Short Random Waves
Authors: Tian Miao , Sheremet Alex , Kaihatu James M. , Ma Gangfeng 
Published: December 2014

AbstractOverhead video from a small number of laboratory tests conducted by Kaihatu et al. at the Tsunami Wave Basin at Oregon State University shows that the breaking point of a shoaling solitary wave shifts to deeper water if random waves are present. The analysis of the laboratory data collected confirms that solitary waves indeed tend to break earlier in the presence of random wave field, and suggests that the effect is the result of the radiation stresses gradient induced by the random wave fields. A theoretical approach based on the forced KdV equation is shown to successfully predict the shoaling process of the solitary wave. An ensemble of tests simulated using a state-of-the-art nonhydrostatic model is used to test the statistical significance of the process. The results of this study point to a potentially significant oceanographic process that has so far been ignored and suggest that systematic research into the interaction between tsunami waves and the swell background could increase the accuracy of tsunami forecasting.
Intraseasonal Variability of Hail in the Contiguous United States: Relationship to the Madden–Julian Oscillation
Authors: Barrett Bradford S. , Henley Brittany N. 
Published: December 2014

Abstract
Climatologies have been developed to highlight variability of the frequency and intensity of hail in the United States. However, the intraseasonal variability of hail, including why one week might be active while the following inactive despite both having similar climatological probabilities, has not yet been explored. This paper presents relationships between spring-season (April–June) hail days and the leading mode of atmospheric intraseasonal variability, the Madden–Julian oscillation (MJO). It extends recent work on intraseasonal tornado variability to smaller spatial scales. In April, May, and June, statistically significant variability in hail days was found for different Real-time Multivariate MJO (RMM) phases of the MJO. For April, the strongest correlations between hail-day anomalies and anomalies of the product of convective available potential energy (CAPE) and 0–6-km vertical wind shear were found in RMM phase 5, with above-normal likelihood of a hail day found in the south-central United States. For May, the strongest correlations were found in RMM phase 3, with below-normal likelihood of a hail day located over the north-central United States. For June, the strongest correlations were found in phase 8, with above-normal likelihood of hail in west Texas and below-normal likelihood of hail over much of the middle of the United States. In all phases, 300-hPa height anomalies in the United States formed part of a global wave train similar to MJO patterns in both modeling and observational studies.
The Role of Nonquasigeostrophic Forcing in Southern Hemisphere Blocking Onsets
Authors: Dong Li , Colucci Stephen J. 
Published: December 2014

Abstract
A generalized frictionless, adiabatic geostrophic zonal wind tendency equation is derived to diagnose the nonquasigeostrophic forcings to blocking onset in the Southern Hemisphere through case study and composite analysis. In general, the quasigeostrophic model is capable of representing the key physical processes associated with blocking onset in the troposphere reasonably well in most blocking cases. The consideration of nonquasigeostrophic forcings moderately improves the quasigeostrophic representation in a majority of the blocking events selected for this study, but not all events. This suggests that the nonquasigeostrophic terms could be important in a specific blocking event but not in a composite meaning. Furthermore, the nonquasigeostrophic forcing of geostrophic advection of ageostrophic relative vorticity term, , is extensively examined in this study. This forcing is found to be the leading nonquasigeostrophic forcing term among all nonquasigeostrophic forcings. In a composite sense, the forcing appears to have an alternative contribution that is dependent upon the curvature of the geostrophic flow within the blocking structure. In general, the southwesterly flow is likely associated with the -favoring effect to blocking onset whereas northwesterly flow is associated with the -opposing effect. Therefore, it is important to use the geostrophic flow pattern prior to blocking onset to foresee this ageostrophic-related nonquasigeostrophic forcing to blocking onset. Finally, a pronounced overestimation of geostrophic zonal wind tendency by the quasigeostrophic model is commonly found for selected blocking events within the stratosphere, in comparison to the nonquasigeostrophic model. This overestimation is essentially caused by geostrophic wind approximation.
Frequency of dendritiform inflammatory cells in the cornea in herpetic anterior uveitis without clinical keratitis and Fuchs uveitis
Authors: Knoll Alexandra B , Postole Andreea S , Auffarth Gerd U , Mackensen Friederike 
Published: December 2014

Abstract

Background
Herpetic anterior uveitis is a frequent cause of infectious uveitis. A definite diagnosis is obtained by anterior chamber puncture and polymerase chain reaction, an invasive procedure. We hypothesized that patients with herpetic anterior uveitis have a certain pattern of inflammatory cells in their cornea that distinguishes herpetic anterior uveitis from other uveitis types. This study is a prospective, controlled, observational study. Ten patients are with active herpetic anterior uveitis and 14 patients are with Fuchs uveitis syndrome. Patients were imaged with the Heidelberg Retina Tomograph with the Rostock Cornea Module attachment. Three images of the subepithelial area of the cornea were evaluated for dendritiform inflammatory cells. Means were calculated and used for analysis. The contralateral unaffected eyes and numbers published in the literature served as controls.

Results
The number of dendritiform inflammatory cells in herpetic anterior uveitis was compared to that in the Fuchs uveitis syndrome. Of the eyes of patients with herpetic anterior uveitis, 80% had an average of 98.0±10.8 cells/mm2 (mean±standard error of the mean (SEM), n=10) in their affected eyes and 60.4±26.4 cells/mm2, (n=6) in 30% of their fellow eyes. Patients with Fuchs uveitis syndrome had moderately elevated dendritiform inflammatory cells (47.0±9.7 cells/mm2, n=14) in 96.4% of their affected eyes and normal numbers (23.0±7.3 cells/mm2, n=13) in 46.4% of their fellow eyes. The difference between the four groups was significant (p=0.0004).

Conclusions
Patients with herpetic anterior uveitis had significantly higher levels of dendritiform inflammatory cells in their subepithelial cornea than patients with Fuchs uveitis syndrome, which can be detected by in vivo confocal microscopy. The clinically unaffected eyes of herpetic anterior uveitis patients showed a co-response regarding dendritiform inflammatory cell elevation. We conclude that high numbers of dendritiform inflammatory cells in the cornea of uveitis patients may support the clinical diagnosis of herpetic anterior uveitis.