bluuebunny/crossref_metadata_2025_split huggingface dataset:
Correlation of Overexpression of Efflux Pump Genes with Antibiotic Resistance inEscherichia coliStrains Clinically Isolated from Urinary Tract Infection Patients
Authors: Yasufuku Tomihiko , Shigemura Katsumi , Shirakawa Toshiro , Matsumoto Minori , Nakano Yuzo , Tanaka Kazushi , Arakawa Soichi , Kinoshita Shouhiro , Kawabata Masato , Fujisawa Masato 
Published: November 2010

ABSTRACTEscherichia coliis one of the most common pathogens in urinary tract infections (UTIs), and antibiotic resistance inE. coliis becoming a serious problem in treating UTI. Efflux system overexpression is reported to contribute toE. coliresistance to several antibiotics. This study investigated the correlation of antibiotic susceptibilities with the overexpression of the efflux pump genes such asmarA,yhiU,yhiV, andmdfAand with risk factors for antibiotic resistance inE. coliisolated from UTI patients. We examined the expression level of efflux pump genes using quantitative real-time reverse transcription-PCR (qRT-PCR). We also tested thein vitrosusceptibilities to 12 kinds of antibiotics in 64 clinical strains ofE. coliisolated from UTI patients. By multivariate analyses we revealed significant relationships between the overexpression of (i)marAand MICs of cefepime (FEP) and nalidixic acid (NAL), (ii)yhiVand MICs of minocycline (MIN), and (iii)mdfAand MICs of sitafloxacin (STX). In our investigation of the efflux pump genes, risk factors such as gender and the previous use of fluoroquinolones correlated with the overexpression ofmarA, and indwelling catheter use correlated with the overexpression ofmdfA. In conclusion, we demonstrated that the increased expression of efflux pump genes such asmarAandmdfAcan lead to fluoroquinolone resistance inE. coli. These results contribute to our knowledge of the efflux system and raise the possibility of developing new agents, such as efflux pump inhibitors (EPIs), to antibiotic-resistantE. coli.
Comparison of Detection Methods for Heteroresistant Vancomycin-Intermediate
Staphylococcus aureus
, with the Population Analysis Profile Method as the Reference Method
Authors: Satola Sarah W. , Farley Monica M. , Anderson Karen F. , Patel Jean B. 
Published: November 2010

ABSTRACT

Staphylococcus aureus
clinical isolates with vancomycin MICs of 2 μg/ml have been associated with vancomycin therapeutic failure and the heteroresistant vancomycin-intermediate
S. aureus
(hVISA) phenotype. A population analysis profile (PAP) with an area under the curve (AUC) ratio of ≥0.9 for the AUC of the clinical isolate versus the AUC for hVISA strain Mu3 is most often used for determining hVISA, but it is time-consuming and labor-intensive. A collection of 140 MRSA blood isolates with vancomycin MICs of 2 μg/ml by reference broth microdilution and screened for hVISA using PAP-AUC (21/140 [15%] hVISA) were tested by additional methods to detect hVISA. The methods included (i) Etest macromethod using vancomycin and teicoplanin test strips, brain heart infusion (BHI) agar, and a 2.0 McFarland inoculum; (ii) Etest glycopeptide resistance detection (GRD) using vancomycin-teicoplanin double-sided gradient test strips on Mueller-Hinton agar (MHA) with 5% sheep blood and a 0.5 McFarland inoculum; and (iii) BHI screen agar plates containing 4 μg/ml vancomycin and 16 g/liter casein using 0.5 and 2.0 McFarland inocula. Each method was evaluated using PAP-AUC as the reference method. The sensitivity of each method for detecting hVISA was higher when the results were read at 48 h. The Etest macromethod was 57% sensitive and 96% specific, Etest GRD was 57% sensitive and 97% specific, and BHI screen agar was 90% sensitive and 95% specific with a 0.5 McFarland inoculum and 100% sensitive and 68% specific with a 2.0 McFarland inoculum. BHI screen agar with 4 μg/ml vancomycin and casein and a 0.5 McFarland inoculum had the best sensitivity and specificity combination, was easy to perform, and may be useful for clinical detection of hVISA.
LysGH15, a Novel Bacteriophage Lysin, Protects a Murine Bacteremia Model Efficiently against Lethal Methicillin-Resistant
Staphylococcus aureus
Infection
Authors: Gu Jingmin , Xu Wei , Lei Liancheng , Huang Jing , Feng Xin , Sun Changjiang , Du Chongtao , Zuo Jing , Li Yang , Du Taofeng , Li Linxi , Han Wenyu 
Published: November 2010

ABSTRACT

Phage-coded lysin is an enzyme that destroys the cell walls of bacteria. Phage lysin could be an alternative to conventional antibiotic therapy against pathogens that are resistant to multiple antibiotics. In this study, a novel staphylococcal phage, GH15, was isolated, and the endogenous lytic enzyme (LysGH15) was expressed and purified. The lysin LysGH15 displayed a broad lytic spectrum;
in vitro
treatment killed a number of
Staphylococcus aureus
strains rapidly and completely, including methicillin-resistant
S. aureus
(MRSA). In animal experiments, a single intraperitoneal injection of LysGH15 (50 μg) administered 1 h after MRSA injections at double the minimum lethal dose was sufficient to protect mice (
P
< 0.01). Bacteremia in unprotected mice reached colony counts of about 10
7
CFU/ml within 3.5 h after challenge, whereas the mean colony count in lysin-protected mice was less than 10
4
CFU/ml (and ultimately became undetectable). These results indicate that LysGH15 can kill
S. aureus in vitro
and can protect mice efficiently from bacteremia
in vivo
. The phage lysin LysGH15 might be an alternative treatment strategy for infections caused by MRSA.
Bocavirus Infection Induces a DNA Damage Response That Facilitates Viral DNA Replication and Mediates Cell Death
Authors: Luo Yong , Chen Aaron Yun , Qiu Jianming 
Published: November 2010

ABSTRACTMinute virus of canines (MVC) is an autonomous parvovirus that replicates efficiently without helper viruses in Walter Reed/3873D (WRD) canine cells. We previously showed that MVC infection induces mitochondrion-mediated apoptosis and G2/M-phase arrest in infected WRD cells. However, the mechanism responsible for these effects has not been established. Here, we report that MVC infection triggers a DNA damage response in infected cells, as evident from phosphorylation of H2AX and RPA32. We discovered that both ATM (ataxia telangiectasia-mutated kinase) and ATR (ATM- and Rad3-related kinase) were phosphorylated in MVC-infected WRD cells and confirmed that ATM activation was responsible for the phosphorylation of H2AX, whereas ATR activation was required for the phosphorylation of RPA32. Both pharmacological inhibition of ATM activation and knockdown of ATM in MVC-infected cells led to a significant reduction in cell death, a moderate correction of cell cycle arrest, and most importantly, a reduction in MVC DNA replication and progeny virus production. Parallel experiments with an ATR-targeted small interfering RNA (siRNA) had no effect. Moreover, we identified that this ATM-mediated cell death is p53 dependent. In addition, we localized the Mre11-Rad50-Nbs1 (MRN) complex, the major mediator as well as a substrate of the ATM-mediated DNA damage response pathway to MVC replication centers during infection, and show that Mre11 knockdown led to a reduction in MVC DNA replication. Our findings are the first to support the notion that an autonomous parvovirus is able to hijack the host DNA damage machinery for its own replication and for the induction of cell death.
Stepwise Loss of Fluorescent Core Protein V from Human Adenovirus during Entry into Cells
Authors: Puntener Daniel , Engelke Martin F. , Ruzsics Zsolt , Strunze Sten , Wilhelm Corinne , Greber Urs F. 
Published: November 2010

ABSTRACT
Human adenoviruses (Ads) replicate and assemble particles in the nucleus. They organize a linear double-strand DNA genome into a condensed core with about 180 nucleosomes, by the viral proteins VII (pVII), pX, and pV attaching the DNA to the capsid. Using reverse genetics, we generated a novel, nonconditionally replicating Ad reporter by inserting green fluorescent protein (GFP) at the amino terminus of pV. Purified Ad2-GFP-pV virions had an oversized complete genome and incorporated about 38 GFP-pV molecules per virion, which is about 25% of the pV levels in Ad2. GFP-pV cofractionated with the DNA core, like pV, and newly synthesized GFP-pV had a subcellular localization indistinguishable from that of pV, indicating that GFP-pV is a valid reporter for pV. Ad2-GFP-pV completed the replication cycle, although at lower yields than Ad2. Incoming GFP-pV (or pV) was not imported into the nucleus. Virions lost GFP-pV at two points during the infection process: at entry into the cytosol and at the nuclear pore complex, where capsids disassemble. Disassembled capsids, positive for the conformation-specific antihexon antibody R70, were devoid of GFP-pV. The loss of GFP-pV was reduced by the macrolide antibiotic leptomycin B (LMB), which blocks nuclear export and adenovirus attachment to the nuclear pore complex. LMB inhibited the appearance of R70 epitopes on Ad2 and Ad2-GFP-pV, indicating that the loss of GFP-pV from Ad2-GFP-pV is an authentic step in the adenovirus uncoating program. Ad2-GFP-pV is genetically complete and hence enables detailed analyses of infection and spreading dynamics in cells and model organisms or assessment of oncolytic adenoviral potential.
Human Cytomegalovirus Early Protein pUL21a Promotes Efficient Viral DNA Synthesis and the Late Accumulation of Immediate-Early Transcripts
Authors: Fehr Anthony R. , Yu Dong 
Published: November 2010

ABSTRACT

We have previously reported that a newly annotated gene of human cytomegalovirus (HCMV), UL21a, encodes an early viral protein termed pUL21a. Most notably, the virions of a UL21a deletion virus had markedly reduced infectivity, indicating that UL21a is required to establish an efficient productive infection. In this study, we infected fibroblasts with equal numbers of DNA-containing viral particles and identified where in the viral life cycle pUL21a acted. The UL21a deletion virus entered cells and initiated viral gene expression efficiently; however, it synthesized viral DNA poorly and accumulated several immediate-early (IE) transcripts at reduced levels at late times of infection. The defect in viral DNA synthesis preceded that in gene expression, and inhibition of viral DNA synthesis reduced the late accumulation of IE transcripts in both wild-type and mutant virus-infected cells to equivalent levels. This suggests that reduced viral DNA synthesis is the cause of reduced IE gene expression in the absence of UL21a. The growth of UL21a deletion virus was similar to that of recombinant HCMV in which pUL21a expression was abrogated by stop codon mutations, and the defect was rescued in pUL21a-expressing fibroblasts. pUL21a expression in
trans
was sufficient to restore viral DNA synthesis and gene expression of mutant virus produced from normal fibroblasts, whereas mutant virus produced from complementing cells still exhibited the defect in normal fibroblasts. Thus, pUL21a does not promote the functionality of HCMV virions; rather, its
de novo
synthesis facilitates viral DNA synthesis, which is necessary for the late accumulation of IE transcripts and establishment of a productive infection.
The Acidic Domain of Hepatitis C Virus NS4A Contributes to RNA Replication and Virus Particle Assembly
Authors: Phan Tung , Kohlway Andrew , Dimberu Peniel , Pyle Anna Marie , Lindenbach Brett D. 
Published: November 2010

ABSTRACT
Hepatitis C virus NS3-4A is a membrane-bound enzyme complex that exhibits serine protease, RNA helicase, and RNA-stimulated ATPase activities. This enzyme complex is essential for viral genome replication and has been recently implicated in virus particle assembly. To help clarify the role of NS4A in these processes, we conducted alanine scanning mutagenesis on the C-terminal acidic domain of NS4A in the context of a chimeric genotype 2a reporter virus. Of 13 mutants tested, two (Y45A and F48A) had severe defects in replication, while seven (K41A, L44A, D49A, E50A, M51A, E52A, and E53A) efficiently replicated but had severe defects in virus particle assembly. Multiple strategies were used to identify second-site mutations that suppressed these NS4A defects. The replication defect of NS4A F48A was partially suppressed by mutation of NS4B I7F, indicating that a genetic interaction between NS4A and NS4B contributes to RNA replication. Furthermore, the virus assembly defect of NS4A K41A was suppressed by NS3 Q221L, a mutation previously implicated in overcoming other virus assembly defects. We therefore examined the known enzymatic activities of wild-type or mutant forms of NS3-4A but did not detect specific defects in the mutants. Taken together, our data reveal interactions between NS4A and NS4B that control genome replication and between NS3 and NS4A that control virus assembly.
Pilot study: a randomised, double blind, placebo controlled trial of pancrealipase for the treatment of postprandial irritable bowel syndrome-diarrhoea
Authors: Money Mary E , Walkowiak Jaroslaw , Virgilio Chris , Talley Nicholas J 
Published: November 2010

ObjectiveTo evaluate the efficacy of pancrealipase (PEZ) compared with placebo in the reduction of postprandial irritable bowel syndrome-diarrhoea (IBS-D).DesignAn intention to treat, double blind, randomised, crossover trial comparing PEZ to placebo for reduction of postprandial IBS-D. Patients had to recognise at least two different triggering foods, be willing to consume six baseline ‘trigger meals’ and again blinded with PEZ and placebo. Patients then chose which drug they preferred for another 25 meals.SettingOutpatient internal medicine practice clinic.Patients255 patients were screened; 83 met the criteria, including 5 years of symptoms, recognised ‘food triggers’, no other identifiable cause for the symptoms, either a normal colonoscopy or barium enema while symptomatic and able to discontinue all anticholinergic medications. 69 patients were enrolled, 20 withdrew before randomisation, leaving 49 patients: 14 men, 35 women, mean age 52 years (SD 15.3). Over 60% had experienced symptoms for 11–30 years and 16% for more than 40 years.InterventionsAfter completing six baseline meals, patients were randomised in blocks of four to receive either identical PEZ or a placebo for another six meals, and after a washout period of time received the alternative drug.Main outcome measuresThe primary analysis was number of patients who chose PEZ over placebo for the extended use.ResultsOverall, 30/49 (61%) would have chosen PEZ (p=0.078), with first drug preference for PEZ at 0.002. Among the PEZ subgroup, PEZ use compared with placebo, demonstrated improvement in all symptoms (p≤0.001) for cramping, bloating, borborygami, urge to defecate, global pain and decrease stooling with increase in stool firmness.ConclusionsPEZ was found in a small group of patients to reduce postprandial IBS-D symptoms and deserves further evaluation.
Proteins responding to drought and high-temperature stress in Pinus armandii Franch
Authors: He Cai-Yun , Zhang Jian-Guo , Duan Ai-Guo , Sun Hong-Gang , Fu Li-Hua , Zheng Shu-Xing 
Published: November 2010

Proteomic analysis provides a powerful method for studying plant responses to stress at the protein level. To study stress-responsive molecular mechanisms for Pinus armandii Franch, one of the most important forest plantation tree species in subalpine regions of Asia, we analyzed the response of 2-year-old P. armandii seedlings to drought and high temperature using two-dimensional gel electrophoresis. More than 550 reproducible needle proteins were detected in the controls and treatments, and the abundance of 27 proteins were found to change noticeably. We identified five proteins affected by drought stress and eight proteins affected by high temperature. These proteins are functionally quite diverse and are involved in photosynthesis, cell division and elongation, antioxidant metabolism, ammonia assimilation, growth and development, and protein folding. Our results provide fundamental data for future research on responses to drought and high temperature. As drought and high temperature are two major factors limiting the growth of subalpine forests during summer under recent global warming, this research may contribute to an understanding of the development of stress tolerance in trees.
Female gametophyte and seed development inMusella lasiocarpa(Musaceae), a monotypic genus endemic to Southwestern China
Authors: Xue Chun-Ying , Wang Hong , Li De-Zhu 
Published: November 2010

Musella is a monotypic genus composed of a single species, Musella lasiocarpa (Franch.) C.Y. Wu ex H.W. Li, endemic to Southwestern China. The genus status of Musella remains controversial. Musella had been placed first in Musa , then in Ensete , and back to Musa before its monotypic status was recognized. Musella was reported to be extinct in the wild and maintained through cultivation only via vegetative propagation through sprouting of rhizomes. In this study, female gametophyte and seed development of Musella are described to assess its systematic position and possible reasons why the wild population is now extinct. The ovules are anatropous, bitegmic, and crassinucellar. The micropyle is formed by both integuments. The megaspore mother cell undergoes meiotic division and forms a linear megaspore triad or more rarely, a T-shaped megaspore tetrad. The chalazal megaspore develops into a Polygonum type embryo sac. A nucellar pad forms, and a hypostase differentiates. Fertilization is porogamous. Endosperm formation is of the nuclear type. The zygote degenerates and so the process by which the embryo develops, if it does, remains unclear. An operculum, micropylar collar, and chalazal chamber form in mature seeds. The storage tissue is mainly endosperm containing large, compound starch grains and some perisperm. The seed coat has lignified exotestal cells, 25–30 cell layers of sclerotic mesotestal cells, and unspecialized endotesta cells; the tegment consists of two layers of longitudinally elongated cells. The seed is inviable. After comparison with the other Musaceae s. str. taxa using embryological and botanical features, we conclude that Musella should be a distinct genus. Female sterility in Musella may be the main reason why the wild population is extinct. Based on these findings, we propose conservation strategies for this endemic species, including habitat protection as well as ex-situ conservation.
Magnetic excitations of spin and orbital moments in cobalt oxideSpecial issue on Neutron Scattering in Canada.
Authors: Yamani Z. , Buyers W. J.L. , Cowley R. A. , Prabhakaran D. 
Published: November 2010

Magnetic and phonon excitations in the antiferromagnet CoO with an unquenched orbital angular momentum are studied by neutron scattering. Results of energy scans in several Brillouin zones in the (HHL) plane for energy transfers up to 16 THz are presented. The measurements were performed in the antiferromagnetic ordered state at 6 K (well below TN ∼290 K) as well as in the paramagnetic state at 450 K. Several magnetic excitation modes are identified from the dependence of their intensity on wavevector and temperature. Within a Hund’s rule model, the excitations correspond to fluctuations of coupled orbital and spin degrees of freedom, whose bandwidth is controlled by interionic superexchange. The different <111> ordering domains give rise to several magnetic peaks at each wavevector transfer.
Abundance of tegu lizards (Tupinambis merianae) in a remnant of the Brazilian Atlantic forest
Authors: Chiarello Adriano , Srbek-Araujo Ana , Del-Duque Jr. Hermano , Coelho Eduardo de , Rocha Carlos 
Published: November 2010

AbstractWe investigated the abundance of the tegu lizard (Tupinambis merianae) in a 21 787 ha Brazilian Atlantic forest fragment (Reserva Natural Vale, RNV). This remnant has a highly irregular perimeter and an extensive network (126 km) of internal unpaved roads. We hypothesized that the high proportion of these edge habitats might benefit active heliothermic lizards like tegus due to greater incidence of sunlight. We estimated population density using the program DISTANCE, and compared sighting frequency of tegus along twelve 500 m long transects located at three distances (25, 200 and 400 m) from the nearest unpaved road or fragment edge. We found no significant differences in sighting frequency among the three distances (Chi-square; χ2 = 4.308; P = 0.116) and no significant association between edge distance and edge type (internal, external) (G test adjusted; G2 = 0.617; P = 0.734). However, as the test comparing distances had relatively low power we assumed that the experimental evidence was not strong enough to prove lack of an edge effect. The estimated density (0.63±0.13 lizard/ha) is within the range of densities found on Brazilian islands where tegus have proliferated to the point of becoming a threat to ground nesting birds and turtles. We caution, however, that the absence of published data on other non-island sites prevents us from concluding that the species has an abnormally high density in RNV.
Evolution of Case in Ossetic
Authors: Belyaev Oleg 
Published: November 2010

AbstractOssetic sets itself apart from the other New Iranian languages by having a relatively elaborate system of nine cases. Since most of them are relatively late innovations, and only four cases (Nom., Gen, Abl., and Iness.) can be traced back to Proto-Iranian, many scholars tend to ascribe the development of the case system to Caucasian influence. The exact nature of this influence, however, has never been demonstrated. The aim of this paper is, first, to not only reconstruct the etymologies of Ossetic cases, but also to provide a chronology of how the case system developed. The second aim pursued here is to give a systematic comparison of the case system of Ossetic with those of the neighbouring languages and to determine if there is any external influence on the case system and, if so, what languages this influence came from. I conclude that Ossetic developed from a case system identical to those of Khotanese and Sogdian towards the present state under the influence of contact with Georgian and, later, with Turkic and Vaynakh languages. In the process of the discussion, I also argue that two new cases, the Directive and Regressive, are undergoing grammaticalisation in contemporary Ossetic.
Regulatory dendritic cells program generation of interleukin-4–producing alternative memory CD4 T cells with suppressive activity
Authors: Xu Xiongfei , Guo Zhenhong , Jiang Xueyu , Yao Yushi , Gao Qiangguo , Ding Yuanyuan , Cao Xuetao 
Published: November 2010

Abstract
The heterogeneity and mechanisms for the generation of CD4 memory T (CD4 Tm) cells remain elusive. Distinct subsets of dendritic cells (DCs) have been found to regulate a distinct T-helper (Th)–cell subset differentiation by influencing cytokine cues around CD4 T cells; however, whether and how the regulatory DC subset can regulate Tm-cell differentiation remains unknown. Further, there is no ideal in vitro experimental system with which to mimic the 3 phases of the CD4 T-cell immune response (expansion, contraction, memory generation) and/or to culture CD4 Tm cells for more than a month. By analyzing CD4 T cells programmed by long-term coculture with regulatory DCs, we identified a population of long-lived CD4 T cells with a CD44hiCD62L−CCR7− effector memory phenotype and rapid, preferential secretion of the Th2 cytokines interleukin-4 (IL-4), IL-5, IL-10, and IL-13 after antigenic stimulation. These regulatory DC-programmed Tm cells suppress CD4 T-cell activation and proliferation in vitro via IL-10 and inhibit the delayed-type hypersensitivity response once infused in vivo. We also identify their natural counterpart, which is up-regulated by regulatory DC transfusion and negatively regulates the recall response in vivo. Different from interferon-γ–producing conventional Tm cells, these IL-4–producing CD4 Tm cells act as alternative Tm cells with a regulatory function, suggesting a new way of negative immune regulation by memory T cells.