bluuebunny/crossref_metadata_2025_split huggingface dataset:
In Vivo Effects on Photosynthesis Gene Expression of Base Pair Exchanges in the Gene Encoding the Light‐responsive BLUF Domain of AppA in Rhodobacter Sphaeroides
Authors: Metz Sebastian , Hendriks Johnny , Jäger Andreas , Hellingwerf Klaas , Klug Gabriele 
Published: May 2010

AbstractThe Rhodobacter sphaeroides protein AppA has the unique quality of sensing and transmitting light and redox signals. By acting as antirepressor to the PpsR protein, it acts as a major regulator in photosynthesis gene expression. In this study, we show that by introducing amino acid exchanges into the AppA protein, the in vivo activity as an antirepressor can be greatly altered. The tryptophan 104 to phenylalanine (W104F) base exchange greatly diminished blue‐light sensitivity of the BLUF domain. From the obtained in vivo data, the difference in thermal recovery rate of the signaling state of the BLUF domain between the wild type and mutated protein was calculated, predicting an about 10‐fold faster recovery in the mutant, which is consistent with in vitro data. Introduction of a tyrosine 21 to phenylalanine (Y21F) or to cysteine (Y21C) mutation led to a complete loss of AppA antirepressor activity, while additionally leading to an increase of photosynthesis gene expression after illumination with high blue‐light quantities. Interestingly, this effect is not visible in a W104F/Y21F double mutant that again shows a wild‐type–like behavior of the BLUF domain after blue‐light illumination, thus restoring the activity of AppA.
Colic in geriatric compared to mature nongeriatric horses. Part 2: Treatment, diagnosis and short‐term survival
Authors: SOUTHWOOD L. L. , GASSERT T. , LINDBORG S. 
Published: May 2010

SummaryReason for performing study:Owners and veterinarians are often concerned about mortality of geriatric horses following colic surgery.Objective:To compare treatment, diagnosis and short‐term survival for geriatric compared to mature nongeriatric horses with colic.Methods:Medical records of horses admitted with a presenting complaint of colic between 2000 and 2006 were reviewed. Geriatric horses were aged ≥16 years (n = 300) and subcategorised as age ≥20 years (n = 134). Mature nongeriatric horses were age 4–15 years (n = 300). Information obtained included medical (included horses subjected to euthanasia without surgery) vs. surgical management, lesion location, type and classification, surgical procedures performed and short‐term survival. Data were analysed using a Chi‐squared test or an analysis of variance. Level of significance was P<0.05.Results:The overall short‐term survival of geriatric horses was lower than that for mature horses (59 vs. 76%, respectively). The survival of medically managed geriatric horses was lower than that for mature horses (58 vs. 80%, respectively). The survival of surgically managed geriatric horses was not different to that for mature horses (59 vs. 70%, respectively) except for geriatric horses age ≥20 years (53%). There was no difference in survival between geriatric and mature horses with small (86 and 83%, respectively) or large (78 vs. 70%, respectively) intestinal strangulating lesions or those undergoing jejunojejunostomy (75 vs. 70%, respectively). Geriatric horses with a large colon simple obstruction had a lower survival compared to mature horses (80 vs. 97%, respectively).Conclusions and potential relevance:The survival of geriatric horses with a strangulating lesion or requiring jejunojejunostomy was not different to that for mature horses. Geriatric horses presenting with colic were more likely than mature horses to be subjected to euthanasia without surgery (i.e. lower survival with medical treatment). Geriatric horses undergoing surgery for a large colon simple obstruction had a lower survival than mature horses.
Pathology of lethal peripartum broad ligament haematoma in 31 Thoroughbred mares
Authors: UENO T. , NAMBO Y. , TAJIMA Y. , UMEMURA T. 
Published: May 2010

SummaryReasons for performing study: Broad ligament haemorrhage in peripartum mares is a life‐threatening disease and there are few reports on the aetiology and pathogenesis of broad ligament haematoma.Objectives: To obtain information regarding the sites for the early diagnosis and pathogenesis of broad ligament haematoma of mares.Methods: Thirty‐one mares that died of broad ligament haematoma peripartum were examined pathologically for bleeding sites. The arterial distribution of 5 young mares with several parities served as negative controls.Results: Age and/or multiparity were the predisposing factors for the disease. Arterial injuries were most commonly observed in the uterine artery (24 of 31 mares). Among these, the proximal uterine artery that lies within 15 cm of the bifurcation of the iliac artery was the most frequent site for rupture (18 mares). The lesions occurred preferentially at the bifurcations, lateral part of curvatures and abrupt flexures of the artery. The morphology of the injuries was classified into 3 types: ruptures with and without longitudinal fissures, and transections. Histologically, the arterial wall adjacent to the rupture showed atrophy of smooth muscle cells with fibrosis of the tunica media and disruption and/or calcification of the internal elastic lamina.Conclusions: Arterial injuries that led to broad ligament haematoma in peripartum mares occurred most frequently in the proximal uterine artery, and atrophy of smooth muscle cells with fibrosis of the arterial wall was as one of the predisposing factors in aged and multiparous mares.Potential relevance: Monitoring small aneurysms, mural tearing, medial fibrosis at the proximal uterine artery by transrectal echography could provide useful information for the early diagnosis and possible prevention of broad ligament haematoma of peripartum mares.
Cell Wall Thickening Is Not a Universal Accompaniment of the Daptomycin Nonsusceptibility Phenotype in
Staphylococcus aureus
: Evidence for Multiple Resistance Mechanisms
Authors: Yang Soo-Jin , Nast Cynthia C. , Mishra Nagendra N. , Yeaman Michael R. , Fey Paul D. , Bayer Arnold S. 
Published: May 2010

ABSTRACT

The mechanism(s) of daptomycin (DAP) resistance (DAP
r
) is incompletely defined. Thickened cell walls (CWs) acting as either a mechanical barrier or an affinity trap for DAP have been purported to be a major contributor to the DAP
r
phenotype. To this end, we studied an isogenic set of methicillin-resistant
Staphylococcus aureus
(MRSA) isolates (pulsotype USA 300) from the bloodstream of a DAP-treated patient with endocarditis in which serial strains exhibited increasing DAP
r
. Of interest, the DAP
r
isolate differed from its parental strain in several parameters, including acquisition of a point mutation within the putative synthase domain of the
mprF
gene in association with enhanced
mprF
expression, increased synthesis of lysyl-phosphotidylglycerol, an enhanced positive envelope charge, and reduced DAP surface binding. Transmission electron microscopy (TEM) revealed no significant increases in CW thickness in the two DAP
r
isolates (MRSA 11/21 and REF2145) compared with that in the DAP-susceptible (DAP
s
) parental strain, MRSA 11/11. The rates of Triton X-100-induced autolysis were also identical for the strain set. Furthermore, among six additional clinically isolated DAP
s
/DAP
r
S. aureus
strain pairs, only three DAP
r
isolates exhibited CWs significantly thicker than those of the respective DAP
s
parent. These data confirm that CW thickening is neither universal to DAP
r
S. aureus
nor sufficient to yield the DAP
r
phenotype among
S. aureus
strains.
Actinohivin, a Broadly Neutralizing Prokaryotic Lectin, Inhibits HIV-1 Infection by Specifically Targeting High-Mannose-Type Glycans on the gp120 Envelope
Authors: Hoorelbeke Bart , Huskens Dana , Férir Geoffrey , François Katrien O. , Takahashi Atsushi , Van Laethem Kristel , Schols Dominique , Tanaka Haruo , Balzarini Jan 
Published: May 2010

ABSTRACT

The lectin actinohivin (AH) is a monomeric carbohydrate-binding agent (CBA) with three carbohydrate-binding sites. AH strongly interacts with gp120 derived from different X4 and R5 human immunodeficiency virus (HIV) strains, simian immunodeficiency virus (SIV) gp130, and HIV type 1 (HIV-1) gp41 with affinity constants (

K
D

) in the lower nM range. The gp120 and gp41 binding of AH is selectively reversed by (α1,2-mannose)
3
oligosaccharide but not by α1,3/α1,6-mannose- or GlcNAc-based oligosaccharides. AH binding to gp120 prevents binding of α1,2-mannose-specific monoclonal antibody 2G12, and AH covers a broader epitope on gp120 than 2G12. Prolonged exposure of HIV-1-infected CEM T-cell cultures with escalating AH concentrations selects for mutant virus strains containing N-glycosylation site deletions (predominantly affecting high-mannose-type glycans) in gp120. In contrast to 2G12, AH has a high genetic barrier, since several concomitant N-glycosylation site deletions in gp120 are required to afford significant phenotypic drug resistance. AH is endowed with broadly neutralizing activity against laboratory-adapted HIV strains and a variety of X4 and/or R5 HIV-1 clinical clade isolates and blocks viral entry within a narrow concentration window of variation (∼5-fold). In contrast, the neutralizing activity of 2G12 varied up to 1,000-fold, depending on the virus strain. Since AH efficiently prevents syncytium formation in cocultures of persistently HIV-1-infected HuT-78 cells and uninfected CD4
+
T lymphocytes, inhibits dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin-mediated capture of HIV-1 and subsequent virus transmission to CD4
+
T lymphocytes, does not upregulate cellular activation markers, lacks mitogenic activity, and does not induce cytokines/chemokines in peripheral blood mononuclear cell cultures, it should be considered a potential candidate drug for microbicidal use.
Assessment of Oritavancin Serum Protein Binding across Species
Authors: Arhin Francis F. , Belley Adam , McKay Geoffrey , Beaulieu Sylvain , Sarmiento Ingrid , Parr Thomas R. , Moeck Gregory 
Published: May 2010

ABSTRACT
Biophysical methods to study the binding of oritavancin, a lipoglycopeptide, to serum protein are confounded by nonspecific drug adsorption to labware surfaces. We assessed oritavancin binding to serum from mouse, rat, dog, and human by a microbiological growth-based method under conditions that allow near-quantitative drug recovery. Protein binding was similar across species, ranging from 81.9% in human serum to 87.1% in dog serum. These estimates support the translation of oritavancin exposure from nonclinical studies to humans.
High-Resolution Melt Curve Analysis for Identification of Single Nucleotide Mutations in the Quinolone Resistance Gene
aac(6′)-Ib-cr
Authors: Hidalgo-Grass Carlos , Strahilevitz Jacob 
Published: May 2010

ABSTRACT

We have developed a simple PCR-based high-resolution melt curve analysis for identification of the quinolone resistance gene
aac(6′)-Ib-cr
through regions encompassing the two defining single nucleotide mutations. Dissociation curves showed 100% concordance with DNA sequencing, including the identification of a strain where
aac(6′)-Ib
and
aac(6′)-Ib-cr
coexist.
A Multiepitope Subunit Vaccine Conveys Protection against Extraintestinal PathogenicEscherichia coliin Mice
Authors: Wieser Andreas , Romann Eva , Magistro Giuseppe , Hoffmann Christiane , Nörenberg Dominik , Weinert Kirsten , Schubert Sören 
Published: May 2010

ABSTRACTInfections due to extraintestinal pathogenicEscherichia coli(ExPEC) are common in humans and animals and include urinary tract infections (from uropathogenicE. coli[UPEC]), septicemia, and wound infections. These infections result in significant morbidity and mortality and in high health care costs. In view of the increasing number of ExPEC infections and the ever-growing antibiotic resistance capability of ExPEC isolates, preventive measures such as an effective vaccine against ExPEC are desirable. An ExPEC vaccine may be cost-effective for select patient groups. Previous vaccine candidates consisted of single target proteins or whole ExPEC cells. Here we describe a subunit vaccine against ExPEC which is based on immunodominant epitopes of the virulence-associated ExPEC proteins FyuA, IroN, ChuA, IreA, Iha, and Usp. Using a novel approach of computer-aided design, two completely artificial genes were created, both encoding eight peptide domains derived from these ExPEC proteins. The recombinant expression of these two genes resulted in a protein vaccine directed against ExPEC but not against commensalE. coliof the gut flora. In mice, the vaccine was highly immunogenic, eliciting both strong humoral and cellular immune responses. Nasal application resulted in high secretory immunoglobulin A (sIgA) production, which was detectable on the mucosal surface of the urogenital tract. Finally, it conveyed protection, as shown by a significant reduction of bacterial load in a mouse model of ExPEC peritonitis. This study provides evidence that a novel vaccine design encompassing distinct epitopes of virulence-associated ExPEC proteins may represent a means for providing a protective and pathogen-specific vaccine.
SecretedAspergillus fumigatusProtease Alp1 Degrades Human Complement Proteins C3, C4, and C5
Authors: Behnsen Judith , Lessing Franziska , Schindler Susann , Wartenberg Dirk , Jacobsen Ilse D. , Thoen Marcel , Zipfel Peter F. , Brakhage Axel A. 
Published: May 2010

ABSTRACTThe opportunistic human pathogenic fungusAspergillus fumigatusis a major cause of fungal infections in immunocompromised patients. Innate immunity plays an important role in the defense against infections. The complement system represents an essential part of the innate immune system. This cascade system is activated on the surface ofA. fumigatusconidia and hyphae and enhances phagocytosis of conidia.A. fumigatusconidia but not hyphae bind to their surface host complement regulators factor H, FHL-1, and CFHR1, which control complement activation. Here, we show thatA. fumigatushyphae possess an additional endogenous activity to control complement activation.A. fumigatusculture supernatant efficiently cleaved complement components C3, C4, C5, and C1q as well as immunoglobulin G. Secretome analysis and protease inhibitor studies identified the secreted alkaline protease Alp1, which is present in large amounts in the culture supernatant, as the central molecule responsible for this cleavage. Analp1deletion strain was generated, and the culture supernatant possessed minimal complement-degrading activity. Moreover, protein extract derived from anEscherichia colistrain overproducing Alp1 cleaved C3b, C4b, and C5. Thus, the protease Alp1 is responsible for the observed cleavage and degrades a broad range of different substrates. In summary, we identified a novel mechanism inA. fumigatusthat contributes to evasion from the host complement attack.
ProtectiveToxoplasma gondii-Specific T-Cell Responses Require T-Cell-Specific Expression of Protein Kinase C-Theta
Authors: Nishanth Gopala , Sakowicz-Burkiewicz Monika , Händel Ulrike , Kliche Stefanie , Wang Xiaoqian , Naumann Michael , Deckert Martina , Schlüter Dirk 
Published: May 2010

ABSTRACTProtein kinase C-theta (PKC-θ) is important for the activation of autoreactive T cells but is thought to be of minor importance for T-cell responses in infectious diseases, suggesting that PKC-θ may be a target for the treatment of T-cell-mediated autoimmune diseases. To explore the function of PKC-θ in a chronic persisting infection in which T cells are crucial for pathogen control, we infected BALB/c PKC-θ−/−and PKC-θ+/+wild-type mice withToxoplasma gondii. The PKC-θ−/−mice succumbed to necrotizingToxoplasmaencephalitis due to an insufficient parasite control up to day 40, whereas the wild-type mice survived. The number ofT. gondii-specific CD4 and CD8 T cells was significantly reduced in the PKC-θ−/−mice, resulting in the impaired production of protective cytokines (gamma interferon, tumor necrosis factor) and antiparasitic effector molecules (inducible nitric oxide, gamma interferon-induced GTPase) in the spleen and brain. In addition, Th2-cell numbers were reduced in infected the PKC-θ−/−mice, paralleled by the diminished GATA3 expression of PKC-θ−/−CD4 T cells and reducedT. gondii-specific IgG production in serum and cerebrospinal fluid. Western blot analysis of splenic CD4 and CD8 T cells revealed an impaired activation of the NF-κB, AP-1, and MAPK pathways inT. gondii-infected PKC-θ−/−mice. Adoptive transfer of wild-type CD4 plus CD8 T cells significantly protected PKC-θ−/−mice from death by increasing the numbers of gamma interferon-producingT. gondii-specific CD4 and CD8 T cells, illustrating a cell-autonomous, protective function of PKC-θ in T cells. These findings imply that PKC-θ inhibition drastically impairsT. gondii-specific T-cell responses with fatal consequences for intracerebral parasite control and survival.
Peyer's Patch-Deficient Mice Demonstrate ThatMycobacterium aviumsubsp.paratuberculosisTranslocates across the Mucosal Barrier via both M Cells and Enterocytes but Has Inefficient Dissemination
Authors: Bermudez Luiz E. , Petrofsky Mary , Sommer Sandra , Barletta Raúl G. 
Published: May 2010

ABSTRACTMycobacterium aviumsubsp.paratuberculosis, the agent of Johne's disease, infects ruminant hosts by translocation through the intestinal mucosa. A number of studies have suggested thatM. aviumsubsp.paratuberculosisinteracts with M cells in the Peyer's patches of the small intestine. The invasion of the intestinal mucosa byM. aviumsubsp.paratuberculosisandMycobacterium aviumsubsp.hominissuis, a pathogen known to interact with intestinal cells, was compared.M. aviumsubsp.paratuberculosiswas capable of invading the mucosa, but it was significantly less efficient at dissemination thanM. aviumsubsp.hominissuis. B-cell knockout (KO) mice, which lack Peyer's patches, were used to demonstrate thatM. aviumsubsp.paratuberculosisenters the intestinal mucosa through enterocytes in the absence of M cells. In addition, the results indicated thatM. aviumsubsp.paratuberculosishad equal abilities to cross the mucosa in both Peyer's patch and non-Peyer's patch segments of normal mice.M. aviumsubsp.paratuberculosiswas also shown to interact with epithelial cells by an α5β1integrin-independent pathway. Upon translocation, dendritic cells ingestM. aviumsubsp.paratuberculosis, but this process does not lead to efficient dissemination of the infection. In summary,M. aviumsubsp.paratuberculosisinteracts with the intestinal mucosa by crossing both Peyer's patches and non-Peyer's patch areas but does not translocate or disseminate efficiently.
‘The missing picture’: tobacco use through the eyes of smokers
Authors: Haines Rebecca J , Oliffe John L , Bottorff Joan L , Poland Blake D 
Published: May 2010

BackgroundThe use of visual methodologies has gained increased prominence among health researchers working with socially marginalised populations, including those studying tobacco and other types of substance use.ObjectivesThis article draws from two separate studies combining qualitative and photographic methods to illustrate the unique insights that visual research with smokers can generate for tobacco control.MethodsA purposeful selection of photographs and captions produced by research participants in a study with (1) 20 new fathers that smoke and, (2) a study with 21 adolescent girls that smoke are analysed and discussed in detail.ResultsImages produced by smokers illustrate the roles of gender and social context in shaping smoking status, as well as the private struggles with tobacco use experienced by smokers in their day-to-day lives and relationships.ConclusionsPhotographic methods have the potential to generate information that may assist in developing tobacco control messaging and programming that speaks to smokers' perceptions of their tobacco use.
Health warning labelling practices on narghile (shisha, hookah) waterpipe tobacco products and related accessories
Authors: Nakkash Rima , Khalil Joanna 
Published: May 2010

BackgroundWaterpipe tobacco smoking prevalence is increasing around the globe despite current evidence that smoke emissions are toxic and contain carcinogenic compounds.ObjectiveTo evaluate current health warning labelling practices on waterpipe tobacco products and related accessories.MethodsAll waterpipe tobacco products, as well as waterpipe accessories, were purchased from Lebanon and a convenience sample was obtained from Dubai (United Arab Emirates), Palestine, Syria, Jordan, Bahrain, Canada, Germany and South Africa.FindingsOf the total number of waterpipe tobacco products collected from Lebanon, the majority had textual health warning labels covering on average only 3.5% of total surface area of the package. Misleading descriptors were commonplace on waterpipe tobacco packages and related accessories.ConclusionsThere are no WHO FCTC compliant waterpipe-specific health warning labels on waterpipe tobacco products and related accessories. Introducing health warnings on waterpipe tobacco products and accessories will probably have worldwide public health benefits.
Semi-volatiles in mainstream smoke delivery from select charcoal-filtered cigarette brand variants
Authors: Hearn Bryan A , Ding Yan S , Vaughan Christina , Zhang Liqin , Polzin Gregory , Caudill Samuel P , Watson Clifford H , Ashley David L 
Published: May 2010

BackgroundIt has been reported that charcoal added to cigarette filters selectively removes many of the more volatile chemicals, but it is not clear to what extent charcoal may reduce the delivery of important less volatile chemical constituents in mainstream cigarette smoke.MethodsWe analysed machine-derived mainstream smoke deliveries (under three smoking regimens) for variants of a charcoal-filtered cigarette commercially test-marketed in the USA, focusing on selected polycyclic aromatic hydrocarbons (PAHs), phenols and tobacco-specific nitrosamines (TSNAs).ResultsWhile charcoal-containing filters selectively removed lower molecular weight PAHs from mainstream smoke, they did not significantly remove the heavier and more toxic PAHs studied, such as benzo[a]pyrene, a known carcinogen. Likewise, charcoal-containing filters removed phenols and TSNAs from mainstream smoke to differing amounts depending on the compound, filter design and the smoking regimen.ConclusionsThe addition of sufficient charcoal to cigarette filters is known to remove many volatile compounds and can potentially reduce deliveries of certain semi-volatile compounds under some machine smoking regimens. Less volatile compounds, with a significant portion in the particulate phase, are less available for selective filtration by charcoal-containing filters than the more volatile compounds that reside predominantly in the gas phase.