bluuebunny/crossref_metadata_2025_split huggingface dataset:
Convergence on Cattle: Political Ecology, Social Group Perceptions, and Socioeconomic Relationships in Acre, Brazil
Authors: Hoelle Jeffrey 
Published: December 2011

AbstractCattle raising is currently the leading cause of deforestation in Amazonia, and an increasingly appealing and profitable way for a growing number of smallholders to make a living in the western Amazon state of Acre, Brazil. The Acrean rubber tapper social movement contested the arrival of cattle ranchers in the 1970s and 1980s, but cattle raising has expanded among smallholder groups, including the rubber tappers, over the past 20 years. Building on the legacy of political–economic analyses of Amazonian cattle raising, this study argues for an expanded view of cattle raising by incorporating perspectives on the cultural constructions surrounding cattle and intergroup socioeconomic relationships. Data obtained from surveys and participant observation are used to examine the factors that have contributed to the expansion of cattle raising across three Acrean groups, each historically distinguished by their unique forms of livelihood and associated identities: forest‐extractivist rubber tappers, agricultural colonists, and large‐scale ranchers. It is argued that three factors have contributed to the growth of cattle ranching among these groups: political and economic shifts, which have made agricultural and extractive livelihoods less competitive with cattle raising; the spread of positive cultural views surrounding cattle raising; and the transition of intergroup relationships from conflict to cooperation in the cattle industry.
Real-Time PCR Analysis of the Intestinal Microbiotas in Peritoneal Dialysis Patients
Authors: Wang I-Kuan , Lai Hsueh-Chou , Yu Cheng-Ju , Liang Chih-Chia , Chang Chiz-Tzung , Kuo Huey-Liang , Yang Ya-Fei , Lin Chung-Chih , Lin Hsin-Hung , Liu Yao-Lung , Chang Yi-Chih , Wu Yi-Ying , Chen Chu-Huang , Li Chi-Yuan , Chuang Feng-Rong , Huang Chiu-Ching , Lin Chih-Hsueh , Lin Hung-Chih 
Published: December 2011

ABSTRACT

Bifidobacterium
and
Lactobacillus
can beneficially affect the host by producing acetic acid and lactic acid, which lower pH and thereby inhibit the growth of pathogens or allow the probiotic bacteria to compete with pathogens for epithelial adhesion sites and nutrients. The transmural migration of enteric organisms into the peritoneal cavity can cause peritonitis in peritoneal dialysis (PD) patients. We hypothesized that the composition of the intestinal microbiota with regard to
Lactobacillus
species and
Bifidobacterium
species differed between PD patients and healthy controls. The aim of the study was to investigate these differences by real-time PCR analysis of fecal samples. From 1 August 2009 to 31 March 2010, a total of 29 nondiabetic PD patients and 41 healthy controls from China Medical University Hospital were recruited after giving their informed consent. Fecal samples were collected from the PD patients and their age-matched counterparts in the morning using a standardized procedure. DNA extracted from these samples was analyzed by real-time PCR. All bifidobacteria,
Bifidobacterium catenulatum
,
B. longum
,
B. bifidum
,
Lactobacillus plantarum
,
L. paracasei
, and
Klebsiella pneumoniae
were less frequently detected in the patient samples. Dysbiosis (microbial imbalance) may impair intestinal barrier function and increase host vulnerability to pathogen invasion. Further studies are necessary to confirm our findings before clinical trials with probiotic supplementation in PD patients.
Highly Efficient Staphylococcus carnosus Mutant Selection System Based on Suicidal Bacteriocin Activation
Authors: Krismer Bernhard , Nega Mulugeta , Thumm Günther , Götz Fritz , Peschel Andreas 
Published: December 2011

ABSTRACT

Strains from various staphylococcal species produce bacteriocin peptides, which are thought to play important roles in bacterial competition and offer interesting biotechnological avenues. Many bacteriocins are secreted as inactive prepeptides with subsequent activation by specific proteolytic cleavage. By deletion of the protease gene
gdmP
in
Staphylococcus gallinarum
Tü3928, which produces the highly active lanthionine-containing bacteriocin gallidermin (lantibiotic), a strain was created producing inactive pregallidermin. On this basis, a new suicidal mutant selection system in the food-grade bacterium
Staphylococcus carnosus
was developed. Whereas pregallidermin was inactive against
S. carnosus
, it exerted potent bactericidal activity toward GdmP-secreting
S. carnosus
strains. To take advantage of this effect,
gdmP
was cloned in plasmid vectors used for random transposon mutagenesis or targeted allelic replacement of chromosomal genes. Both mutagenesis strategies rely on rare recombination events, and it has remained difficult and laborious to identify mutants among a vast majority of bacterial clones that still contain the delivery vectors. The
gdmP
-expressing plasmids pGS1 and pGS2 enabled very fast, easy, and reliable identification of transposon and gene replacement mutants, respectively. Mutant selection in the presence of pregallidermin caused suicidal inactivation of all clones that had retained the plasmids and allowed growth of only plasmid-cured mutants. Efficiency of mutant identification was several magnitudes higher than standard screening for the absence of plasmid-encoded antibiotic resistance markers and reached 100% specificity. Thus, the new pregallidermin-based mutant selection system represents a substantial improvement of staphylococcal mutagenesis methodology.
Evolutionary Silence of the Acid Chaperone Protein HdeB in Enterohemorrhagic Escherichia coli O157:H7
Authors: Carter Michelle Q. , Louie Jacqueline W. , Fagerquist Clifton K. , Sultan Omar , Miller William G. , Mandrell Robert E. 
Published: December 2011

ABSTRACT

The periplasmic chaperones HdeA and HdeB are known to be important for cell survival at low pH (pH < 3) in
Escherichia coli
and
Shigella
spp. Here we investigated the roles of HdeA and HdeB in the survival of various enterohemorrhagic
E. coli
(EHEC) following exposure to pH 2.0. Similar to K-12 strains, the acid protections conferred by HdeA and HdeB in EHEC O145 were significant: loss of HdeA and HdeB led to over 100- to 1,000-fold reductions in acid survival, depending on the growth condition of prechallenge cells. However, this protection was much less in
E. coli
O157:H7 strains. Deletion of
hdeB
did not affect the acid survival of cells, and deletion of
hdeA
led to less than a 5-fold decrease in survival. Sequence analysis of the
hdeAB
operon revealed a point mutation at the putative start codon of the
hdeB
gene in all 26
E. coli
O157:H7 strains analyzed, which shifted the ATG start codon to ATA. This mutation correlated with the lack of HdeB in
E. coli
O157:H7; however, the plasmid-borne O157-
hdeB
was able to restore partially the acid resistance in an
E. coli
O145Δ
hdeAB
mutant, suggesting the potential function of O157-HdeB as an acid chaperone. We conclude that
E. coli
O157:H7 strains have evolved acid survival strategies independent of the HdeA/B chaperones and are more acid resistant than nonpathogenic K-12 for cells grown under nonfavorable culturing conditions such as in Luria-Bertani no-salt broth at 28°C. These results suggest a divergent evolution of acid resistance mechanisms within
E. coli
.
How Posttranslational Modification of Nitrogenase Is Circumvented in Rhodopseudomonas palustris Strains That Produce Hydrogen Gas Constitutively
Authors: Heiniger Erin K. , Oda Yasuhiro , Samanta Sudip K. , Harwood Caroline S. 
Published: December 2011

ABSTRACTNitrogenase catalyzes the conversion of dinitrogen gas (N2) and protons to ammonia and hydrogen gas (H2). This is a catalytically difficult reaction that requires large amounts of ATP and reducing power. Thus, nitrogenase is not normally expressed or active in bacteria grown with a readily utilized nitrogen source like ammonium.nifA*mutants of the purple nonsulfur phototrophic bacteriumRhodopseudomonas palustrishave been described that express nitrogenase genes constitutively and produce H2when grown with ammonium as a nitrogen source. This raised the regulatory paradox of why these mutants are apparently resistant to a known posttranslational modification system that should switch off the activity of nitrogenase. Microarray, mutation analysis, and gene expression studies showed that posttranslational regulation of nitrogenase activity inR. palustrisdepends on two proteins: DraT2, an ADP-ribosyltransferase, and GlnK2, an NtrC-regulated PIIprotein. GlnK2 was not well expressed in ammonium-grown NifA* cells and thus not available to activate the DraT2 nitrogenase modification enzyme. In addition, the NifA* strain had elevated nitrogenase activity due to overexpression of thenifgenes, and this increased amount of expression overwhelmed a basal level of activity of DraT2 in ammonium-grown cells. Thus, insufficient levels of both GlnK2 and DraT2 allow H2production by annifA*mutant grown with ammonium. Inactivation of the nitrogenase posttranslational modification system by mutation ofdraT2resulted in increased H2production by ammonium-grown NifA* cells.
MADS Box Transcription Factor Mbx2/Pvg4 Regulates Invasive Growth and Flocculation by Inducing
gsf2
+
Expression in Fission Yeast
Authors: Matsuzawa Tomohiko , Yoritsune Ken-ichi , Takegawa Kaoru 
Published: December 2011

ABSTRACT

The fission yeast
Schizosaccharomyces pombe
exhibits invasive growth and nonsexual flocculation in response to nitrogen limitation. Gsf2, a flocculin of fission yeast, is required not only for nonsexual flocculation but also for invasive growth through the recognition of galactose residues on cell surface glycoconjugates. We found that pyruvylation negatively regulates nonsexual flocculation by capping the galactose residues of
N
-linked galactomannan. We investigated whether pyruvylation also regulates invasive growth. The
pvg4
+
gene originally was isolated as a multicopy suppressor of a
pvg4
mutant defective in the pyruvylation of
N
-linked oligosaccharides. However, we did not detect a defect in cell surface pyruvylation in the
pvg4
/
mbx2
deletion mutant, as assessed by alcian blue staining and a Q-Sepharose binding assay. Instead, the deletion prevented invasive growth under conditions of low nitrogen and high glucose, and it reduced the adhesion and flocculation of otherwise flocculent mutants by reducing
gsf2
+
expression.
mbx2
+
-overexpressing strains exhibited nonsexual and calcium-dependent aggregation, which was inhibited in the presence of galactose but mediated by the induction of
gsf2
+
. These findings indicate that Mbx2 mediates invasive growth and flocculation via the transcriptional activation of
gsf2
+
in fission yeast. In addition, we found that fission yeast Mbx2 induces the nonsexual flocculation of budding yeast by the activation of
FLO1
.
Membrane Topology of the Bacillus anthracis GerH Germinant Receptor Proteins
Authors: Wilson Mary J. , Carlson Paul E. , Janes Brian K. , Hanna Philip C. 
Published: December 2011

ABSTRACT

Bacillus anthracis
spores are the etiologic agent of anthrax. Nutrient germinant receptors (nGRs) packaged within the inner membrane of the spore sense the presence of specific stimuli in the environment and trigger the process of germination, quickly returning the bacterium to the metabolically active, vegetative bacillus. This ability to sense the host environment and initiate germination is a required step in the infectious cycle. The nGRs are comprised of three subunits: the A-, B-, and C-type proteins. To date there are limited structural data for the A- and B-type nGR subunits. Here the transmembrane topologies of the
B. anthracis
GerH
A
, GerH
B
, and GerH
C
proteins are presented. C-terminal green fluorescent protein (GFP) fusions to various lengths of the GerH proteins were overexpressed in vegetative bacteria, and the subcellular locations of these GFP fusion sites were analyzed by flow cytometry and protease sensitivity. GFP fusion to full-length GerH
C
confirmed that the C terminus of this protein is extracellular, as predicted. GerH
A
and GerH
B
were both predicted to be integral membrane proteins by topology modeling. Analysis of C-terminal GFP fusions to full-length GerH
B
and nine truncated GerH
B
proteins supports either an 8- or 10-transmembrane-domain topology. For GerH
A
, C-terminal GFP fusions to full-length GerH
A
and six truncated GerH
A
proteins were consistent with a four-transmembrane-domain topology. Understanding the membrane topology of these proteins is an important step in determining potential ligand binding and protein-protein interaction domains, as well as providing new information for interpreting previous genetic work.
Herpesvirus Replication Compartments Originate with Single Incoming Viral Genomes
Authors: Kobiler O. , Brodersen P. , Taylor M. P. , Ludmir E. B. , Enquist L. W. 
Published: December 2011

ABSTRACT

Previously we described a method to estimate the average number of virus genomes expressed in an infected cell. By analyzing the color spectrum of cells infected with a mixture of isogenic pseudorabies virus (PRV) recombinants expressing three fluorophores, we estimated that fewer than seven incoming genomes are expressed, replicated, and packaged into progeny per cell. In this report, we expand this work and describe experiments demonstrating the generality of the method, as well as providing more insight into herpesvirus replication. We used three isogenic PRV recombinants, each expressing a fluorescently tagged VP26 fusion protein (VP26 is a capsid protein) under the viral VP26 late promoter. We calculated a similar finite limit on the number of expressed viral genomes, indicating that this method is independent of the promoter used to transcribe the fluorophore genes, the time of expression of the fluorophore (early versus late), and the insertion site of the fluorophore gene in the PRV genome (UL versus US). Importantly, these VP26 fusion proteins are distributed equally in punctate virion assembly structures in each nucleus, which improves the signal-to-noise ratio when determining the color spectrum of each cell. To understand how the small number of genomes are distributed among the replication compartments, we used a two-color fluorescent
in situ
hybridization assay. Most viral replication compartments in the nucleus occupy unique nuclear territories, implying that they arose from single genomes. Our experiments suggest a correlation between the small number of expressed viral genomes and the limited number of replication compartments.

IMPORTANCE
Herpesviruses use nuclear factors and architecture to replicate their DNA genomes in the host nuclei. Viral replication compartments are distinct nuclear foci that appear during productive infection. We have recently developed a method that uses three viral recombinants (each expressing a different fluorescent protein) to quantify the number of incoming viral genomes that are expressed and replicated in each cell. We found that fewer than seven herpesvirus genomes can be expressed and replicated. Here we have expanded and improved upon our method and demonstrated that the phenomenon of limited genome expression is independent of the recombinants used. We correlated the small number of genomes expressed to the limited number of replication compartments by demonstrating that most replication compartments originate with a single genome. The distinction among replication compartments is maintained even when most of the nucleus is filled with viral DNA, implying that nuclear architecture constrains the compartments.
Dissemination of the Klebsiella pneumoniae Carbapenemase in the Health Care Settings: Tracking the Trails of an Elusive Offender
Authors: Adler Amos , Carmeli Yehuda 
Published: December 2011

ABSTRACT

Transmission of antibiotic resistance genes may be mediated by a variety of molecular mechanisms, from mobility of small genetic elements to clonal spread. Since 1997, the carbapenem-hydrolyzing enzyme
Klebsiella pneumoniae
carbapenemase (KPC) has spread in the United States and across the world, mainly via a single
K. pneumoniae
clone, sequence type 258. By tracking the trail of dissemination of the
bla
KPC
gene inside their institution, Mathers et al. (mBio 2:e00204–11, 2011) have shown evidence of the ability of this gene to spread by several modes, including plasmid transfer and clonal spread. The ever-evolving modes of transmission of resistance genes challenge our ability to detect, track, and eventually control the spread of what has become a major threat to hospitalized patients worldwide.
Intravenous paracetamol versus morphine for renal colic in the emergency department: a randomised double-blind controlled trial
Authors: Serinken Mustafa , Eken Cenker , Turkcuer Ibrahim , Elicabuk Hayri , Uyanik Emrah , Schultz Carl H 
Published: December 2011

ObjectiveTo determine the analgesic efficacy and safety of intravenous single-dose paracetamol versus morphine in patients presenting to the emergency department with renal colic.MethodsA randomised double-blind study was performed to compare the efficacy of intravenous paracetamol (1 g) and 0.1 mg/kg morphine in patients with renal colic. The efficacy of the study drugs was measured by a visual analogue scale and a verbal rating scale at baseline and after 15 and 30 min. The adverse effects and need for rescue medication (1 μg/kg intravenous fentanyl) were also recorded at the end of the study.Results133 patients were eligible for enrolment in the study, with 73 patients included in the final analysis (38 in the paracetamol group and 35 in the morphine group). The mean±SD age of the subjects was 30.2±8.6 years and 51 (70%) were men. The mean reduction in scores at 30 min after study drug administration was 63.7 mm (95% CI 57 to 71) for paracetamol and 56.6 mm (95% CI 48 to 65) for morphine. The difference between pain reduction scores for the two groups at 30 min was 7.1 mm (95% CI −18 to 4), demonstrating no statistical or clinical significance. Two adverse events (5.3%) were recorded in the paracetamol group and five (14.3%) in the morphine group (difference 9%, 95% CI −7% to 26%).ConclusionIntravenous paracetamol is effective in treating patients presenting with renal colic to the emergency department.Clinical trials registration noClinicalTrials.gov ID numberNCT01318187.
The need for a usable assessment tool to analyse the efficacy of emergency care systems in developing countries: proposal to use the TEWS methodology
Authors: Sun Jared H , Twomey Michele , Tran Jeffrey , Wallis Lee A 
Published: December 2011

BackgroundNinety percent of emergency incidents occur in developing countries, and this is only expected to get worse as these nations develop. As a result, governments in developing countries are establishing emergency care systems. However, there is currently no widely-usable, objective method to monitor or research the rapid growth of emergency care in the developing world.MethodsAnalysis of current quantitative methods to assess emergency care in developing countries, and the proposal of a more appropriate method.ResultsCurrently accepted methods to quantitatively assess the efficacy of emergency care systems cannot be performed in most developing countries due to weak record-keeping infrastructure and the inappropriateness of applying Western derived coefficients to developing country conditions. As a result, although emergency care in the developing world is rapidly growing, researchers and clinicians are unable to objectively measure its progress or determine which policies work best in their respective countries. We propose the TEWS methodology, a simple analytical tool that can be handled by low-resource, developing countries.ConclusionsBy relying on the most basic universal parameters, simplest calculations and straightforward protocol, the TEWS methodology allows for widespread analysis of emergency care in the developing world. This could become essential in the establishment and growth of new emergency care systems worldwide.
Detection of elephant endotheliotropic herpesvirus type 1 in asymptomatic elephants using TaqMan real‐time PCR
Authors: Hardman K. , Dastjerdi A. , Gurrala R. , Routh A. , Banks M. , Steinbach F. , Bouts T. 
Published: December 2011

This study assessed the feasibility of identifying asymptomatic viral shedders using a novel TaqMan real‐time PCR on trunk washes and swabs from the conjunctiva, palate and vulva of elephants. Six elephants from a UK collection were sampled weekly over a period of 11 weeks for this study. The herd prevalence of elephant endotheliotropic herpesvirus‐1 (EEHV‐1) was 100 per cent by PCR. The virus DNA was detected in all the sampling sites; however, the prevalence of virus DNA in the conjunctiva swabs was higher. In addition, Asian elephants from two continental European collections were sampled once and one animal tested positive on a trunk wash. The virus from this animal was phylogenetically typed as EEHV‐1A based on 231 nucleotides of the terminase gene.
Myc Posttranscriptionally Induces HIF1 Protein and Target Gene Expression in Normal and Cancer Cells
Authors: Doe Megan R. , Ascano Janice M. , Kaur Mandeep , Cole Michael D. 
Published: December 2011

Abstract
c-Myc is frequently overexpressed in tumors and plays an important role in the regulation of cancer metabolism. Hypoxia-inducible factor-1 (HIF1), the master regulator of the hypoxic response, enhances tumorigenesis and influences metabolism via upregulation of the glycolytic pathway and suppression of mitochondrial respiration. Together, deregulated Myc and HIF1 cooperate to lend metabolic advantages to proliferating cancer cells and contribute to the Warburg effect. Here we show that overexpression of Myc significantly stabilizes the α subunit of HIF1 (HIF1α) under normoxic conditions and enhances HIF1α accumulation under hypoxic conditions in cells. Posttranscriptional regulation of HIF1α by Myc led to the induction of HIF1α gene targets. Normoxic HIF1α protein expression was also dependent on Myc. Functionally, HIF1α expression was required for Myc-induced anchorage-independent growth and cell proliferation. Myc-dependent stabilization of HIF1α involved either disruption of binding to the VHL complex or posttranslational protein modifications. Taken together, our findings uncover a previously uncharacterized regulatory relationship between Myc and HIF1 that has important implications for cancer metabolism and development. Cancer Res; 72(4); 949–57. ©2011 AACR.