bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Symbiosis Regulator CbrA Modulates a Complex Regulatory Network Affecting the Flagellar Apparatus and Cell Envelope Proteins
Authors: Gibson Katherine E. , Barnett Melanie J. , Toman Carol J. , Long Sharon R. , Walker Graham C. 
Published: January 2007

ABSTRACT

Sinorhizobium meliloti
participates in a nitrogen-fixing symbiosis with legume plant host species of the genera
Medicago
,
Melilotus
, and
Trigonella
. We recently identified an
S. meliloti
two-component sensory histidine kinase, CbrA, which is absolutely required to establish a successful symbiosis with
Medicago sativa
(K. E. Gibson, G. R. Campbell, J. Lloret, and G. C. Walker, J. Bacteriol. 188:4508-4521, 2006). In addition to having a symbiotic defect, the
cbrA
::Tn
5
mutant also has free-living phenotypes that suggest a cell envelope perturbation. Because the bases for these phenotypes are not well understood, we undertook an identification of CbrA-regulated genes. We performed a microarray analysis and compared the transcriptome of the
cbrA
::Tn
5
mutant to that of the wild type. Our global analysis of gene expression identified 162 genes that are differentially expressed in the
cbrA
::Tn
5
mutant, including those encoding proteins involved in motility and chemotaxis, metabolism, and cell envelope function. With regard to those genes with a known role in symbiosis, we observed increased expression of nine genes with overlapping functions in bacterial invasion of its host, which suggests that the mutant could be competent for invasion. Since these CbrA-repressed genes are vital to the invasion process, it appears that down-regulation of CbrA activity is important at this stage of nodule development. In contrast, our previous work showed that CbrA is required for bacteria to establish themselves within the host as nitrogen-fixing symbionts. Therefore, we propose a model in which CbrA functions as a developmental switch during symbiosis.
Functional Characterization of the Gene Cluster from
Pseudomonas syringae
pv. phaseolicola NPS3121 Involved in Synthesis of Phaseolotoxin
Authors: Aguilera Selene , López-López Karina , Nieto Yudith , Garcidueñas-Piña Rogelio , Hernández-Guzmán Gustavo , Hernández-Flores José Luis , Murillo Jesús , Alvarez-Morales Ariel 
Published: January 2007

ABSTRACT

Pseudomonas syringae
pv. phaseolicola is the causal agent of halo blight disease of beans (
Phaseolus vulgaris
L.), which is characterized by water-soaked lesions surrounded by a chlorotic halo resulting from the action of a non-host-specific toxin known as phaseolotoxin. This phytotoxin inhibits the enzyme ornithine carbamoyltransferase involved in arginine biosynthesis. Different evidence suggested that genes involved in phaseolotoxin production were clustered. Two genes had been previously identified in our laboratory within this cluster:
argK
, which is involved in the immunity of the bacterium to its own toxin, and
amtA
, which is involved in the synthesis of homoarginine. We sequenced the region around
argK
and
amtA
in
P. syringae
pv. phaseolicola NPS3121 to determine the limits of the putative phaseolotoxin gene cluster and to determine the transcriptional pattern of the genes comprising it. We report that the phaseolotoxin cluster (Pht cluster) is composed of 23 genes and is flanked by insertion sequences and transposases. The mutation of 14 of the genes within the cluster lead to a Tox
−
phenotype for 11 of them, while three mutants exhibited low levels of toxin production. The analysis of fusions of selected DNA fragments to
uidA
, Northern probing, and reverse transcription-PCR indicate the presence of five transcriptional units, two monocistronic and three polycistronic; one is internal to a larger operon. The site for transcription initiation has been determined for each promoter, and the putative promoter regions were identified. Preliminary results also indicate that the gene product of
phtL
is involved in the regulation of the synthesis of phaseolotoxin.
SOS Regulation of the Type III Secretion System of EnteropathogenicEscherichia coli
Authors: Mellies Jay L. , Haack Kenneth R. , Galligan Derek C. 
Published: January 2007

ABSTRACTGenomes of bacterial pathogens contain and coordinately regulate virulence-associated genes in order to cause disease. EnteropathogenicEscherichia coli(EPEC), a major cause of watery diarrhea in infants and a model gram-negative pathogen, expresses a type III secretion system (TTSS) that is encoded by the locus of enterocyte effacement (LEE) and is necessary for causing attaching and effacing intestinal lesions. Effector proteins encoded by the LEE and in cryptic prophage are injected into the host cell cytoplasm by the TTTS apparatus, ultimately leading to diarrhea. The LEE is comprised of multiple polycistronic operons, most of which are controlled by the global, positive regulator Ler. Here we demonstrated that theLEE2andLEE3operons also responded to SOS signaling and that this regulation was LexA dependent. As determined by a DNase I protection assay, purified LexA protein bound in vitro to a predicted SOS box located in the divergent, overlappingLEE2/LEE3promoters. Expression of thelexA1allele, encoding an uncleavable LexA protein in EPEC, resulted in reduced secretion, particularly in the absence of the Ler regulator. Finally, we obtained evidence that the cryptic phage-locatednleAgene encoding an effector molecule is SOS regulated. Thus, we demonstrated, for the first time to our knowledge, that genes encoding components of a TTSS are regulated by the SOS response, and our data might explain how a subset of EPEC effector proteins, encoded in cryptic prophages, are coordinately regulated with the LEE-encoded TTSS necessary for their translocation into host cells.
Functional Characterization and Membrane Topology of
Escherichia coli
WecA, a Sugar-Phosphate Transferase Initiating the Biosynthesis of Enterobacterial Common Antigen and O-Antigen Lipopolysaccharide
Authors: Lehrer Jason , Vigeant Karen A. , Tatar Laura D. , Valvano Miguel A. 
Published: January 2007

ABSTRACT

WecA is an integral membrane protein that initiates the biosynthesis of enterobacterial common antigen and O-antigen lipopolysaccharide (LPS) by catalyzing the transfer of
N
-acetylglucosamine (GlcNAc)-1-phosphate onto undecaprenyl phosphate (Und-P) to form Und-P-P-GlcNAc. WecA belongs to a large family of eukaryotic and prokaryotic prenyl sugar transferases. Conserved aspartic acids in putative cytoplasmic loops 2 (Asp90 and Asp91) and 3 (Asp156 and Asp159) were targeted for replacement mutagenesis with either glutamic acid or asparagine. We examined the ability of each mutant protein to complement O-antigen LPS synthesis in a
wecA
-deficient strain and also determined the steady-state kinetic parameters of the mutant proteins in an in vitro transfer assay. Apparent

K
m

and
V
max
values for UDP-GlcNAc, Mg
2+
, and Mn
2+
suggest that Asp156 is required for catalysis, while Asp91 appears to interact preferentially with Mg
2+
, possibly playing a role in orienting the substrates. Topological analysis using the substituted cysteine accessibility method demonstrated the cytosolic location of Asp90, Asp91, and Asp156 and provided a more refined overall topological map of WecA. Also, we show that cells expressing a WecA derivative C terminally fused with the green fluorescent protein exhibited a punctate distribution of fluorescence on the bacterial surface, suggesting that WecA localizes to discrete regions in the bacterial plasma membrane.
Activity patterns, blood lactate concentrations and ratings of perceived exertion during a professional singles tennis tournament
Authors: Mendez-Villanueva Alberto , Fernandez-Fernandez Jaime , Bishop David , Fernandez-Garcia Benjamin , Terrados Nicolas 
Published: January 2007

Objective:To examine the game characteristics and physiological (ie, blood lactate concentration) and perceptual (ie, rating of perceived exertion, RPE) responses during actual tennis competition in professional performers.Methods:Eight trained and internationally ranked (Association of Tennis Professionals rankings) male tennis players were studied during singles matches (best of three sets) played on an outdoor clay court surface during a professional, invitational tournament. Blood lactate concentrations (n = 53) and RPE (n = 113) were determined at selected changeovers during the game. The variables describing the characteristics of the matches, (a) duration of rallies (DRs); (b) rest time (RT); (c) effective playing time (EPT); and (d) shots per rally (SR), were determined from video recordings.Results:The mean (SD) values for the match-play activity variables were DR 7.5 (7.3) s, RT 16.2 (5.2) s, EPT 21.5 (4.9%), SR 2.7 (2.2) shots. Average blood lactate concentration and RPE values were 3.8 (2.0) mmol/l and 13 (2). Blood lactate concentrations and RPE values were significantly higher (p<0.01) in service games than in receiving games. Both blood lactate concentration and RPE values were significantly correlated with SR and DR (r = 0.80 to 0.28; p<0.001).Conclusions:Blood lactate concentrations and RPE were found to be influenced by the characteristics of the match and the playing situation (ie, serving or returning). These specific situations might be used to alter the overload training stimulus during tennis on-court practice.
High incidence of exercise-induced bronchoconstriction in triathletes of the Swiss national team
Authors: Knöpfli Bruno H , Luke-Zeitoun Mona , von Duvillard Serge P , Burki Adrian , Bachlechner Christian , Keller Heidi 
Published: January 2007

Aim:To assess the progression of bronchial reactivity (BR) and incidence of bronchial hyperreactivity (BH), exercise-induced bronchoconstriction (EIB) and asthma in triathletes over 2 years.Methods:Subjects were seven athletes from the Swiss national triathlon team (mean (SD) age 24.3 (4.8) years), who initially were not asthmatic, not treated with antiasthmatic medication, and who had performed at international level for more than 3 consecutive years (2001–2003). To assess BR, BH and EIB, subjects ran on a 400 m track for 8 min at intensities equal to the anaerobic threshold. Tests were conducted in ambient temperatures of 4.4 (2.8)°C, –8.8 (2.4)°C and 3.6 (1.5)°C, and humidity of 52 (16)%, 83 (13)% and 93 (2)%. Forced expiratory volume in 1 s (FEV1) was measured before and at 2, 5, 10 and 15 min after EIB, and 5 min after inhalation of a β2 agonist. Two methods were used to calculate the incidence: (1) the standard assessment; (2) extrapolation of the decrease in FEV1to the BH limit.Results:BR increased significantly in the seven athletes (FEV1: year, p = 0.04; year × EIB, p = 0.002; EIB p<0.001). Within 2 years, BR had increased significantly and even reached BH in some athletes. Three athletes exhibited BH. After extrapolation of the decrease in FEV1in all seven athletes, the limit of 10% by definition for BH was determined to occur within 1.77–4.81 years, resulting in 21–57% of athletes with newly developed BH per year.Conclusion:Athletes develop EIB quickly, a rate of increase 195–286 times that of the normal rate for development of asthma.
Jamestown Canyon virus detection in human tissue specimens
Authors: Zheng Huachuan , Murai Yoshihiro , Hong Mei , Nakanishi Yuko , Nomoto Kazuhiro , Masuda Shinji , Tsuneyama Koichi , Takano Yasuo 
Published: January 2007

Aim:To clarify the advantages and disadvantages of different detection methods for Jamestown Canyon virus (JCV) in human tissue specimens.Methods:Specimens of lung and gastric carcinomas, and normal lung tissue, gastric mucosa, and tonsil were examined forT-antigen,VPand agnoprotein of JCV by nested PCR, Southern blotting and sequencing. JCV load targetingT-antigenwas evaluated by real-time PCR, and JCV existence morphologically by immunohistochemistry, in-situ hybridisation (ISH) and PCR. For these experiments, the JCI cell line (JCV cultured neuroblastoma cell line) was employed as positive control.Results:In lung and gastric carcinomas,T-antigen,VPandagnoproteinof JCV could be detected by nested PCR whose products were confirmed by Southern blots and sequencing. With real-time PCR, frozen samples of gastric carcinomas gave better detection of JCV than their corresponding paraffin-embedded tissues (p<0.05). The positive rate of JCV was high in lung carcinoma, compared with normal lung tissue (p<0.05). It was the same for JCV copies in gastric carcinoma (p<0.05). Only the positive control exhibited JCV in the nucleus by ISH and immunohistochemistry. In-situ PCR showed that JCV genomic DNA was located in the nucleus of the carcinoma cell, some alveolar epithelial cells, and tonsil lymphocytes. In ISH and PCR, NBT/BCIP colouring was stronger than Fuchsin.Conclusions:Nested PCR whose amplicons should be confirmed by Southern blot and sequencing was a comparatively sensitive approach to detect JCV genomic DNA in human non-neural tissues. Real-time PCR might be employed to quantify copy number of JCV. In-situ PCR was a good method to observe the JCV location in cells, given appropriate modulation of amplification cycles. Combinations of various approaches will be adopted to explore the oncogenic roles of JCV in malignancies.
The Methodological Contribution of Günther Zuntz to the Text of Hebrews
Authors: Güting Eberhard 
Published: January 2007

AbstractThis essay seeks to bring into focus the methodological presuppositions and the specific approach of the textual critic and classical scholar Günther Zuntz. In his study, The Text of the Epistles (1953), Zuntz redefined the task of philological analysis. He insisted that recensio, examinatio, and emendatio need to be applied to the enormously accumulating evidence. Accepting Griesbach's notion of three large regional sources of New Testament texts, Zuntz criticized Griesbach's assumption that recensional activities, exerted a formative influence upon early regional texts. He was willing to demonstrate that each source of transmission is capable of testifying independently.
Approaches to Scripture in the Fourth Gospel and the Qumran Pesharim
Authors: Witmer Stephen 
Published: January 2007

AbstractMany scholars have noticed similarities between the Fourth Gospel and the Qumran pesharim in their approaches to Scripture. However, comparisons between the two corpora are usually made in passing, often do not offer careful definition of what constitutes the pesher genre, and tend to isolate certain features for comparison. This essay begins from the conviction that it is important to carefully define the pesher genre before comparing it with the Fourth Gospel. After developing a definition based primarily on form and content, a broad-based comparison with the Fourth Gospel is carried out, giving attention to some previously overlooked similarities. In particular, it is demonstrated that John 6:31-58 is perhaps more pesher-like than any other passage in the Fourth Gospel. However, it is concluded that, while there are impressive similarities between the Fourth Gospel's exegesis and that of the pesharim, the differences are sufficient that it is not justifiable to speak of the former as pesher exegesis.
The Date of the Fannius Letter: Jos. Ant. 14.233
Authors: Zollschan Linda 
Published: January 2007

AbstractThe letter of safe-conduct to Jewish envoys in Jos. Ant. 14.233 is widely held, following Niese, to have been written by the consul of 161 B.C.E., C. Fannius Strabo although the letter is placed by Josephus among Roman documents that date to 49 B.C.E. The circumstances of the civil war go some way to explaining the extraordinary nature of this document: the element of danger present on Cos in 49 B.C.E., danger that was not present in the second c. B.C.E., the legend PR on the Asian cistophori of C. Fannius and the meaning of the phrase στρατηγòς νπατoς. The letter is addressed to the archons of Cos, a form of address found in the rst but not the second c. B.C.E. Research from the last three decades provide fresh considerations that argue for an identi cation of the author of the letter with C. Fannius, the governor of Asia in 49/8 B.C.E., a date which accords with the chronological position given by Josephus.
Philo of Alexandria and the Conquest of Canaan
Authors: Berthelot Katell 
Published: January 2007

AbstractAccording to the Torah, the Hebrews were commanded either to expel or to exterminate the Canaanites who were living in Canaan at the time of the conquest. Philo seems to feel rather ill-at-ease about the literal meaning of these biblical passages. Besides allegory, he uses four hermeneutical strategies: 1) to pass over the problematic texts in silence; 2) to play with the meaning of certain Greek words; 3) to justify the destruction of the Canaanites from a moral point of view; 4) to rewrite the biblical account.
Familial Dimensions of Group Identity (II): "Mothers" and "Fathers" in Associations and Synagogues of the Greek World
Authors: Harland Philip 
Published: January 2007

AbstractFictive parental language (e.g. "mother of the synagogue," "father of the association") has drawn limited attention within two scholarly circles, namely, those who study diaspora synagogues, on the one hand, and ancient historians, on the other. is article brings these two scholarly interests together and argues, based on inscriptional evidence, that parental metaphors were more widespread and significant in cities and associations of the Greek East than o en acknowledged. Such terminology was an important way of expressing honour, hierarchy, and/or belonging within the association or community, and it could also pertain to functional leadership roles (rather than mere honorifics) in certain cases. e Jewish practice of calling figures "mother" or "father" of the synagogue can be better understood within this cultural framework and in relation to associations specifically.
The Origin of the Tradition
Authors: Cook Johann 
Published: January 2007

AbstractThe rabbinic tradition of the good and evil yesarim inherent in man is wide-spread in rabbinic and other sources. There seems to be a development from pre-Christian origins to fully-fledged later, Talmudic and Amoraic perspectives. This article traces this development from its later forms back to its possible origin via relevant Jewish texts from Hellenistic writings (Ben Sira and the LXX of Proverbs) and Qumran. It concludes that this tradition was already in use in Palestine during the 2nd century B.C.E.
Quality-of-Life Assessment When There Is a Loss of Income
Authors: Myers John , McCabe Steven , Gohmann Stephan 
Published: January 2007

Purpose. The current study aims to provide the first empirical evidence demonstrating whether people automatically consider morbidity costs when assessing the quality of life for a health state. Methods. One hundred eighty-one undergraduate students were randomly assigned to 1 of 2 groups: 1) those participants who were not informed of morbidity costs and 2) those participants who were informed of morbidity costs. Students were asked to read a description of a health state and to assign an assessment of quality of life for the health state described by the use of the paper standard gamble. Results. The overall mean quality of life for the informed group was significantly lower than that of the uninformed group (P < 0.0001, F = 24.2, df = 1, 179). Similarly, there is a significant difference between illness severity levels in mean quality of life (P < 0.0001, F = 29.5, df = 2, 178). No statistically significant interaction between level of illness severity and prior knowledge was observed (P = 0.5904, F = 0.53, df = 2, 178). Therefore, the authors fit a model removing the interaction term. Conclusion. This study demonstrates that those subjects informed of morbidity costs score quality of life lower than do subjects unin-formed of morbidity costs. To accurately represent the effectiveness of an intervention, the authors argue that morbidity costs should be included in the description of health states.
Further Insight into the Perception of Quantitative Information: Judgments of Gist in Treatment Decisions
Authors: Feldman-Stewart Deb , Brundage Michael D. , Zotov Vladimir 
Published: January 2007

Purpose. To compare relative accuracy and relative response times (RTs) as well as impact of foreground and background colors in a treatment decision context of judging larger/smaller when the following elements are added to the graphics studied previously: 1) a number (the displayed percentage), 2) a referent scale, and 3) a number and a referent scale. Method. An experiment compared pie charts, vertical bars, horizontal bars, digits, systematic ovals, and random ovals. On each trial, participants saw 2 percentages (in 1 format) and were asked to choose the larger chance of survival or the smaller chance of side effects. Outcomes were errors and RT. Formats were either black and white or blue and yellow; background color was either white or blue. Participants were 216 volunteers from the community older than 50 years. Results. Formats with a number produced the same relative errors and relative RT as the formats with a number and scale. Formats with only a scale, however, shifted relative performance: Errors increased with more difficult formats (pie charts and random ovals by 3%-4% v. ∼ 1% with other formats), but RT decreased with easier formats (vertical bars, horizontal bars, and systematic ovals decreased 100-200 ms v. an increase of 0-300 ms with other formats). Vertical bars with scales were the fastest and most accurately processed. Neither foreground nor background color had any impact on either outcome. Conclusions. For supporting older people’s judgments of relative extent, risk information is best presented using vertical bars with a scale; the format systematic ovals with a scale are among the next most easily processed.
Measuring Health Preferences for Health Utilities Index Mark 3 Health States: A Study of Feasibility and Preference Differences among Ethnic Groups in Singapore
Authors: Luo Nan , Wang Qinan , Feeny David , Chen Geraldine , Li Shu-Chuen , Thumboo Julian 
Published: January 2007

Background. Little is known about the health preferences of Southeast Asians. The authors therefore investigated the feasibility of measuring health preferences of Chinese, Malays, and Indians in Singapore and compared their preference scores. Methods. A stratified random sample of the Singaporean general population was interviewed to measure preferences for a set of health states defined by the Health Utilities Index Mark 3 (HUI3) using both the rating scale (RS) and the standard gamble (SG) methods. Feasibility of preference measurement was assessed using ratings of measurement tasks, task completion rates, and ranking of preference scores. Differences in preference scores across Chinese, Malays, and Indians were examined using analysis of variance models. Results. Among 245 interviewed respondents (Chinese: 110, Malays: 73, Indians: 62), 97.1% and 95.1% successfully completed all the RS and SG measurement tasks, respectively; 70.1% and 75.3% judged the RS and SG tasks as “easy” or “very easy,” respectively. Interviewers rated 69.4% and 75.0% of these respondents as having “full comprehension” for the RS and SG tasks, respectively; “full concentration” was observed in 84.1% and 84.0% of these respondents for the RS and SG tasks, respectively. There were no significant differences in mean preference scores across Chinese, Malays, and Indians, with and without adjustment for effects of confounding variables. Conclusions. RS and SG are feasible methods for measuring health preferences for Asians in Singapore; it appears that Chinese, Malays, and Indians in Singapore have similar preferences for HUI3 health states.