bluuebunny/crossref_metadata_2025_split huggingface dataset:
RGD Motif of Lipoprotein T, Involved in Adhesion ofMycoplasma conjunctivaeto Lamb Synovial Tissue Cells
Authors: Zimmermann Liza , Peterhans Ernst , Frey Joachim 
Published: May 2010

ABSTRACTLipoprotein T (LppT), a membrane-located 105-kDa lipoprotein ofMycoplasma conjunctivae, the etiological agent of infectious keratoconjunctivitis (IKC) of domestic sheep and wild Caprinae, was characterized. LppT was shown to promote cell attachment to LSM 192 primary lamb joint synovial cells. Adhesion ofM. conjunctivaeto LSM 192 cells is inhibited by antibodies directed against LppT. The RGD (Arg-Gly-Asp) motif of LppT was found to be a specific site for binding ofM. conjunctivaeto these eukaryotic host cells. Recombinant LppT fixed to polymethylmethacrylate slides binds LSM 192 cells, whereas LppT lacking the RGD site is deprived of binding capacity to LSM 192, and LppT containing RGE rather than RGD shows reduced binding. Synthetic nonapeptides derived from LppT containing RGD competitively inhibit binding of LSM 192 cells to LppT-coated slides, whereas nonapeptides containing RAD rather than RGD do not inhibit. RGD-containing, LppT-derived nonapeptides are able to directly inhibit binding ofM. conjunctivaeto LSM 192 cells by competitive inhibition, whereas the analogous nonapeptide containing RAD rather than RGD or the fibronectin-derived RGD hexapeptide has no inhibitory effect. These results reveal LppT as the first candidate of a RGD lectin inMycoplasmaspecies that is assumed to bind to β integrins.
Complete Genome Sequence Analysis of
Leuconostoc kimchii
IMSNU 11154
Authors: Oh Hyun-Myung , Cho Yong-Joon , Kim Byung Kwon , Roe Jung-Hye , Kang Sa-Ouk , Nahm Baek Hie , Jeong Gajin , Han Hong-Ui , Chun Jongsik 
Published: May 2010

ABSTRACT

Leuconostoc kimchii
IMSNU 11154, isolated from kimchi, a traditional Korean fermented food, is known to be an important antimicrobial lactic acid bacterium with probiotic potential. Here we announce the complete genome sequence of
L. kimchii
IMSNU 11154 consisting of a 2,101,787-bp chromosome and five plasmids. The strain has genes for dextran formation from sucrose and for mannitol formation from fructose. Antimicrobial and antioxidative functions of
L. kimchii
IMSNU 11154 could be attributed to a leucosin B-like peptide and multiple enzymes to reduce hydrogen peroxide and oxidized thiols, respectively.
Simple Sequence Repeats and Genome Plasticity inStreptococcus agalactiae
Authors: Janulczyk Robert , Masignani Vega , Maione Domenico , Tettelin Hervé , Grandi Guido , Telford John L. 
Published: May 2010

ABSTRACTSimple sequence repeats (SSRs) and their role in phase variation have been extensively studied in Gram-negative organisms, where they have been associated with antigenic variation and other adaptation strategies. In this study, we apply comparative genomics in order to find evidence of slipped-strand mispairing in the human Gram-positive pathogenStreptococcus agalactiae. In two consecutive screenings, 2,233 (650 + 1,583) SSRs were identified in our reference genome 2603V/R, and these loci were examined in seven otherS. agalactiaegenomes. A total of 56 SSR loci were found to exhibit variation, where gain or loss of repeat units was observed in at least one other genome, resulting in aberrant genotypes. Homopolymeric adenine tracts predominated among the repeats that varied. Positional analysis revealed that long polyadenine tracts were overrepresented in the 5′ ends of open reading frames (ORFs) and underrepresented in the 3′ ends. Repeat clustering in ORFs was also examined, and the highest degree of clustering was observed for a capsule biosynthesis gene and a pilus sortase. A statistical analysis of observed over expected ratios suggested a selective pressure against long homopolymeric tracts. Altered phenotypes were verified for three genes encoding surface-attached proteins, in which frameshifts or fusions led to truncation of proteins and/or affected surface localization through loss or gain of the cell wall sorting signal. The data suggest that SSRs contributes to genome plasticity inS. agalactiaebut that the bet-hedging strategy is different from Gram-negative organisms.
Comparison of Meropenem MICs and Susceptibilities for Carbapenemase-Producing
Klebsiella pneumoniae
Isolates by Various Testing Methods
Authors: Bulik Catharine C. , Fauntleroy Kathy A. , Jenkins Stephen G. , Abuali Mayssa , LaBombardi Vincent J. , Nicolau David P. , Kuti Joseph L. 
Published: May 2010

ABSTRACT

We describe the levels of agreement between broth microdilution, Etest, Vitek 2, Sensititre, and MicroScan methods to accurately define the meropenem MIC and categorical interpretation of susceptibility against carbapenemase-producing
Klebsiella pneumoniae
(KPC). A total of 46 clinical
K. pneumoniae
isolates with KPC genotypes, all modified Hodge test and
bla
KPC
positive, collected from two hospitals in NY were included. Results obtained by each method were compared with those from broth microdilution (the reference method), and agreement was assessed based on MICs and Clinical Laboratory Standards Institute (CLSI) interpretative criteria using 2010 susceptibility breakpoints. Based on broth microdilution, 0%, 2.2%, and 97.8% of the KPC isolates were classified as susceptible, intermediate, and resistant to meropenem, respectively. Results from MicroScan demonstrated the most agreement with those from broth microdilution, with 95.6% agreement based on the MIC and 2.2% classified as minor errors, and no major or very major errors. Etest demonstrated 82.6% agreement with broth microdilution MICs, a very major error rate of 2.2%, and a minor error rate of 2.2%. Vitek 2 MIC agreement was 30.4%, with a 23.9% very major error rate and a 39.1% minor error rate. Sensititre demonstrated MIC agreement for 26.1% of isolates, with a 3% very major error rate and a 26.1% minor error rate. Application of FDA breakpoints had little effect on minor error rates but increased very major error rates to 58.7% for Vitek 2 and Sensititre. Meropenem MIC results and categorical interpretations for carbapenemase-producing
K. pneumoniae
differ by methodology. Confirmation of testing results is encouraged when an accurate MIC is required for antibiotic dosing optimization.
Further Analysis of Marek's Disease Virus Horizontal Transmission Confirms That U
L
44 (gC) and U
L
13 Protein Kinase Activity Are Essential, while U
S
2 Is Nonessential
Authors: Jarosinski Keith W. , Osterrieder Nikolaus 
Published: May 2010

ABSTRACT

Marek's disease virus (MDV) causes a devastating disease in chickens characterized by the development of lymphoblastoid tumors in multiple organs and is transmitted from the skin of infected chickens. We have previously reported that the U
S
2, U
L
44 (glycoprotein C [gC]), and U
L
13 genes are essential for horizontal transmission of MDV in gain-of-function studies using an a priori spread-deficient virus that was based on an infectious clone from the highly virulent RB-1B virus (pRB-1B). To precisely determine the importance of each individual gene in the process of chicken-to-chicken transmission, we used the transmission-restored clone that readily transmits horizontally and mutated each individual gene in loss-of-function experiments. Two independent U
S
2-negative mutants transmitted horizontally, eliminating U
S
2 as being essential for the process. In contrast, the absence of gC expression or mutating the invariant lysine essential for U
L
13 kinase activity abolished horizontal spread of MDV between chickens.
Multiple Pathways Involved in Porcine Parvovirus Cellular Entry and Trafficking toward the Nucleus
Authors: Boisvert Maude , Fernandes Sandra , Tijssen Peter 
Published: May 2010

ABSTRACT
Porcine parvovirus (PPV) is a major cause of reproductive failure in swine. The mechanisms implicated in the first steps of infection that lead to the delivery of the PPV genome to the nucleus are poorly understood. In the present work, a panel of chemical inhibitors was used to dissect the cellular mechanisms involved in establishing a PPV infection. The results demonstrated that following binding to sialic acids on cell surface glycoproteins, the virus used both clathrin-mediated endocytosis and macropinocytosis pathways to gain access into cells. Virus obtained from infected cells was present either as isolated particles or as aggregates, and these two forms could be separated by low-speed centrifugation. Isolated and purified particles strongly preferred entry by clathrin-mediated endocytosis, whereas aggregates clearly favored macropinocytosis. Subsequent endosomal acidification and traffic to the late endosomes were also shown to be essential for infection. The microtubule network was found to be important during the first 10 h of infection, whereas an intact actin network was required for almost the whole viral cycle. Proteasome processing was found to be essential, and capsid proteins were ubiquitinated relatively early during infection. Taken together, these results provided new insights into the first steps of PPV infection, including the use of alternative entry pathways, unique among members of this viral family.
High Prevalence, Coinfection Rate, and Genetic Diversity of Retroviruses in Wild Red Colobus Monkeys (
Piliocolobus badius badius
) in Taï National Park, Côte d'Ivoire
Authors: Leendertz Siv Aina J. , Junglen Sandra , Hedemann Claudia , Goffe Adeelia , Calvignac Sebastien , Boesch Christophe , Leendertz Fabian H. 
Published: May 2010

ABSTRACT

Simian retroviruses are precursors of all human retroviral pathogens. However, little is known about the prevalence and coinfection rates or the genetic diversity of major retroviruses—simian immunodeficiency virus (SIV), simian T-cell lymphotropic virus type 1 (STLV-1), and simian foamy virus (SFV)—in wild populations of nonhuman primates. Such information would contribute to the understanding of the natural history of retroviruses in various host species. Here, we estimate these parameters for wild West African red colobus monkeys (
Piliocolobus badius badius
) in the Taï National Park, Côte d'Ivoire. We collected samples from a total of 54 red colobus monkeys; samples consisted of blood and/or internal organs from 22 monkeys and additionally muscle and other tissue samples from another 32 monkeys. PCR analyses revealed a high prevalence of SIV, STLV-1, and SFV in this population, with rates of 82%, 50%, and 86%, respectively. Forty-five percent of the monkeys were coinfected with all three viruses while another 32% were coinfected with SIV in combination with either STLV or SFV. As expected, phylogenetic analyses showed a host-specific pattern for SIV and SFV strains. In contrast, STLV-1 strains appeared to be distributed in genetically distinct and distant clades, which are unique to the Taï forest and include strains previously described from wild chimpanzees in the same area. The high prevalence of all three retroviral infections in
P. b. badius
represents a source of infection to chimpanzees and possibly to humans, who hunt them.
HIV-1 Protease Has a Genetic T-Cell Adjuvant Effect Which Is Negatively Regulated by Proteolytic Activity
Authors: Kim Kwang Soon , Jin Dong Bin , Ahn So Shin , Park Ki Seok , Seo Sang Hwan , Suh You Suk , Sung Young Chul 
Published: May 2010

ABSTRACT
HIV protease (PR) mediates the processing of human immunodeficiency virus (HIV) polyproteins and is necessary for the viral production. Recently, HIV PR was shown to possess both cytotoxic and chaperonelike activity. We demonstrate here that HIV PR can serve as a genetic adjuvant that enhances the HIV Env and human papillomavirus (HPV) DNA vaccine-induced T-cell response in a dose-dependent manner, only when codelivered with DNA vaccine. Interestingly, the T-cell adjuvant effects of HIV PR were increased by introducing several mutations that inhibited its proteolytic activity, indicating that the adjuvant properties were inversely correlated with its proteolytic activity. Conversely, the introduction of a mutation in the flap region of HIV PR limiting the access to the core domain of HIV PR inhibited the T-cell adjuvant effect, suggesting that the HIV PR chaperonelike activity may play a role in mediating T-cell adjuvant properties. A similar adjuvant effect was also observed in adenovirus vaccine, indicating vaccine type independency. These findings suggest that HIV PR can modulate T-cell responses elicited by a gene-based vaccine positively by inherent chaperonelike activity and negatively by its proteolytic activity.
Design of a protocol for large-scale epidemiological studies in individual sports: the Swedish Athletics injury study
Authors: Jacobsson Jenny , Timpka Toomas , Ekberg Joakim , Kowalski Jan , Nilsson Sverker , Renström Per 
Published: May 2010

BackgroundEpidemiological studies have mainly been performed on team sports. The authors set out to develop a protocol for large-scale epidemiological studies of injuries among elite athletics athletes.MethodsAn argument-based method for investigation of complex design problems was used to structure the collection and analysis of data. Specification of the protocol was preceded by an examination of requirements on injury surveillance in individual sports and iterated drafting of protocol specifications, and followed by formative evaluations.ResultsThe requirements analysis shows that the central demand on the protocol is to allow for detailed epidemiological analyses of overuse injuries, which subsequently requires regular collection of self-reported data from athletes. The resulting study protocol is centred on a web-based weekly athlete e-diary enabling continual collection of individual-level data on exposure and injuries. To be able to interpret the self-reported data on injury events, collection of a wide range of personal baseline data from the athlete, including a psychological profile, is included in the protocol.ConclusionsThe resulting protocol can be employed in intervention programmes that can prevent suffering among both adult elite and youth talent athletes who have made considerable life investments in their sport.
The effect of acute fish-oil supplementation on endothelial function and arterial stiffness following a high-fat meal
Authors: Fahs Christopher A. , Yan Huimin , Ranadive Sushant , Rossow Lindy M. , Agiovlasitis Stamatis , Wilund Kenneth R. , Fernhall Bo 
Published: May 2010

This study examined whether a commercially available fish-oil supplement offers protection from the acute effects of a high-fat meal (HFM) on endothelial function and arterial stiffness. An HFM causes acute impairments in endothelial function, whereas the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have a variety of cardioprotective effects. However, little is known about the efficacy of moderate fish-oil supplementation on the endothelial dysfunction induced by an HFM. Endothelial function (brachial artery flow-mediated dilation (FMD)), forearm blood flow (FBF), total hyperemia, central and peripheral blood pressure, and central artery stiffness were assessed in 20 healthy men (n = 10) and women (n = 10) at rest and 4 h after an HFM supplemented with either placebo or ∼1 g EPA and DHA. Brachial artery FMD normalized for shear rate was significantly impaired (p = 0.033) following the HFM with placebo but remained unchanged compared with baseline following the HFM with the fish-oil supplement (p = 0.039; condition × time interaction). Resting FBF (p = 0.020) and total hyperemia (p = 0.014) were elevated following the HFM. All other vascular and hemodynamic measurements were unchanged in both trials. Commercially available fish-oil supplements taken with an HFM appear to preserve endothelial function following an HFM.
Effects of high-density lipoprotein on endothelium-dependent vasorelaxation
Authors: McAllister Richard M. , Morris David M. , Weimer Cory M. , Laughlin M. Harold 
Published: May 2010

Studies using cultured endothelial cells have shown that high-density lipoprotein (HDL) positively modulates endothelial nitric oxide synthase (eNOS). The purpose of this study was to test the hypotheses that positive modulation of eNOS by HDL occurs in whole vessels and that it augments endothelium-dependent vasorelaxation. To test these hypotheses, brachial arteries were obtained from swine. Endothelium-dependent and endothelium-independent vasorelaxation were determined in vitro to assess the effects of acute administration of HDL (50 μg·mL–1; n = 8) and chronic exposure to relatively high HDL concentration on vascular function (low HDL, 0.89 ± 0.02 mmol·L–1, n = 4; high HDL, 1.16 ± 0.05 mmol·L–1, n = 4; p < 0.005). Acute administration of HDL did not augment maximal endothelium-dependent vasorelaxation to bradykinin (BK) (no HDL, 82.6% ± 2.2%; HDL, 76.7% ± 3.5%; not significant (ns)). Similarly, maximal relaxation to BK was not enhanced by chronic exposure to high HDL concentrations. NO synthase (NOS) activity was also similar between groups (low HDL, 129.0 ± 19.2 counts·h–1·μg–1 protein; high HDL, 113.9 ± 47.1 counts·h–1·μg–1; ns). Consistent with NOS activity, the extent of eNOS phosphorylation at several sites was similar between low HDL and high HDL. Both apolipoprotein A-I (ApoA-I) and scavenger receptor class B type I (SR-BI) were associated with eNOS. Similar to cultured cell studies, this study demonstrates that both ApoA-I and SR-BI associate with eNOS in the vascular wall. Binding of ApoA-I and SR-BI to eNOS does not, however, result in modulation of either NO formation or endothelial function.
On-ice sweat rate, voluntary fluid intake, and sodium balance during practice in male junior ice hockey players drinking water or a carbohydrate–electrolyte solution
Authors: Palmer Matthew S. , Logan Heather M. , Spriet Lawrence L. 
Published: May 2010

This study evaluated the repeatability of hydration and sweat measurements taken during on-ice hockey practices with players drinking only water, and determined whether having only a carbohydrate–electrolyte solution (CES) to drink during practices decreased fluid intake or affected other hydration and (or) sweat measures. All testing was conducted on elite players of an Ontario Hockey League team (±SE; mean age, 17.6 ± 0.3 years; mean height, 182.9 ± 1.4 cm; mean body mass, 83.0 ± 1.7 kg). Players were studied 3 times over the course of 6 weekly on-ice practices (±SE; mean playing time, 1.58 ± 0.07 h; mean temperature, 11.4 ± 0.8 °C; mean relative humidity, 52% ± 3%). There was strong repeatability of the measured hydration and sweat parameters between 2 similar on-ice practices when players drank only water. Limiting the players to drinking only a CES (as opposed to water) did not decrease fluid intake during practice (±SE; mean CES intake, 0.72 ± 0.07 L·h–1 vs. mean water intake, 0.82 ± 0.08 L·h–1) or affect sweat rate (1.5 ± 0.1 L·h–1 vs. 1.5 ± 0.1 L·h–1), sweat sodium concentration (72.4 ± 5.6 mmol·L–1 vs. 73.0 ± 4.4 mmol·L–1), or percent body mass loss (1.1% ± 0.2% vs. 0.9% ± 0.2%). Drinking a CES also improved sodium balance (–2.1 ± 0.2 g·h–1 vs. –2.6 ± 0.3 g·h–1) and provided the players with a significant carbohydrate (43 ± 4 g·h–1 vs. 0 ± 0 g·h–1) during practice. In summary, a single field sweat test during similar on-ice hockey practices in male junior hockey players is sufficient to evaluate fluid and electrolyte balance. Also, a CES does not affect voluntary fluid intake during practice, compared with water, in these players. The CES provided some salt to offset the salt lost in sweat, and carbohydrate, which may help maintain physical and mental performance in the later stages of practice.
Origami in outer membrane mimetics: correlating the first detailed images of refolded VDAC with over 20 years of biochemical data
Authors: Summers William A.T. , Court Deborah A. 
Published: May 2010

Mitochondrial porin forms an aqueous pore in the outer membrane, through which selective passage of small metabolites and ions occurs, thereby regulating both mitochondrial function and cellular respiration. Investigations of the structure and function of porin have been performed with whole mitochondria, membrane vesicles, artificial membranes, and in detergent solutions, resulting in numerous models of porin structure. The mechanisms by which this protein functions are undoubtedly linked to its structure, which remained elusive until 2008, with reports of 3 high-resolution structures of this voltage-dependent, anion-selective channel (VDAC). The barrel structure is relatively simple yet unique: it is arranged as 19 anti-parallel β-strands, with β-strands 1 and 19 aligned parallel to each other to close the barrel. The N-terminal helical component is located within the lumen of the channel, although its precise structure and location in the lumen varies. With the basic barrel structure in hand, the data obtained in attempts to model the structure and understand porin over the past 20 years can be re-evaluated. Herein, using the mammalian VDAC structures as templates, the amassed electrophysiological and biochemical information has been reassessed with respect to the functional mechanisms of VDAC activity, with a focus on voltage-dependent gating.
Structural analysis of DNA interaction with retinol and retinoic acid
Authors: Mandeville J. S. , N’soukpoé-Kossi C. N. , Neault J. F. , Tajmir-Riahi H. A. 
Published: May 2010

Dietary constituents of fresh fruits and vegetables may play a relevant role in DNA adduct formation by inhibiting enzymatic activities. Studies have shown the important role of antioxidant vitamins A, C, and E in the protection against cancer and cardiovascular diseases. The antioxidant activity of vitamin A and beta-carotene may consist of scavenging oxygen radicals and preventing DNA damage. This study was designed to examine the interaction of calf-thymus DNA with retinol and retinoic acid in aqueous solution at physiological conditions using a constant DNA concentration and various retinoid contents. Fourier transform infrared (FTIR), circular dichroism (CD), and fluorescence spectroscopic methods were used to determine retinoid binding mode, the binding constant, and the effects of retinol and retinoic acid complexation on DNA conformation and aggregation. Structural analysis showed that retinol and retinoic acid bind DNA via G-C and A-T base pairs and the backbone phosphate groups with overall binding constants of Kret = 3.0 (±0.50) × 103 (mol·L–1)–1 and Kretac = 1.0 (±0.20) × 104 (mol·L–1)–1. The number of bound retinoids per DNA were 0.84 for retinol and 1.3 for retinoic acid. Hydrophobic interactions were also observed at high retinol and retinoic acid contents. At a high retinoid concentration, major DNA aggregation occurred, while DNA remained in the B-family structure.