bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of a stress management program on vital exhaustion and depression in women with coronary heart disease: a randomized controlled intervention study
Authors: Koertge J. , Janszky I. , Sundin Ö. , Blom M. , Georgiades A. , László K. D. , Alinaghizadeh H. , Ahnve S. 
Published: February 2008

Abstract.Objectives.  Psychosocial factors, including depression and vital exhaustion (VE) are associated with adverse outcome in coronary heart disease (CHD). Women with CHD are poor responders to psychosocial treatment and knowledge regarding which treatment modality works in them is limited. This randomized controlled clinical study evaluated the effect of a 1‐year stress management program, aimed at reducing symptoms of depression and VE in CHD women.Design.  Patients were 247 women, ≤75 years, recruited consecutively after a cardiac event and randomly assigned to either stress management (20 2‐h sessions) and medical care by a cardiologist, or to obtaining usual health care as controls. Measurements at; baseline (6–8 weeks after randomization), 10 weeks (after 10 intervention sessions), 1 year (end of intervention) and 1–2 years follow‐up.Results.  For VE, intention to treat analysis showed effects for time (P < 0.001) and time × treatment interaction (P = 0.005), reflecting that both groups improved over time, and that the decrease of VE was more pronounced in the intervention group. However, the level of VE was higher in the intervention group than amongst controls at baseline, 22.7 vs. 19.4 (P = 0.036) but it did not differ later. The change in depressive symptoms did not differ between the groups.Conclusions.  CHD women attending our program experienced a more pronounced decrease in VE than controls. However, as they had higher baseline levels, due to regression towards the mean we cannot attribute the decrease in VE to the intervention. Whether the program has long‐term beneficial effects needs to be evaluated.
Do troponin and B‐natriuretic peptide detect cardiomyopathy in transthyretin amyloidosis?
Authors: Suhr O. B. , Anan I. , Backman C. , Karlsson A. , Lindqvist P. , Mörner S. , Waldenström A. 
Published: February 2008

Abstract.Objectives.  Cardiomyopathy is a well known complication in familial amyloidotic polyneuropathy (FAP). Troponin T and B‐natriuretic peptide (BNP) have been shown to be excellent markers for heart complications in AL‐amyloidosis. The aim of the study was to investigate troponin T, troponin I and BNP as markers for myocardial damage and failure in FAP.Design.  Retrospective investigation of patients with FAP.Setting.  Tertiary referral centre.Subjects.  Twenty‐nine patients who had been submitted for evaluation of FAP.Interventions.  Two‐dimensional M‐mode and Doppler echocardiography and strain echocardiographic examination. Measurement of Troponin T, troponin I and BNP.Results.  Troponin T was detectable in only three patients who all had abnormal interventricular septal (IVS) thickness. Troponin I was abnormal in six patients (21%), of which only two had an increased IVS thickness. The heart function was generally well preserved in the patients in spite of hypertrophy of the IVS in 14 patients. BNP was elevated in 22 patients (76%), and it correlated significantly with IVS thickness and basal septal strain.Conclusions.  Transthyretin amyloid seems to be less harmful to myocytes than that of AL amyloid as evaluated by serum troponin T and I as well as by echocardiography. BNP appears to be a sensitive marker for cardiomyopathy in FAP, and could prove valuable for follow‐up purposes as has been shown for AL‐amyloidosis patients.
Telomere attrition is associated with inflammation, low fetuin‐A levels and high mortality in prevalent haemodialysis patients
Authors: Carrero J. J. , Stenvinkel P. , Fellström B. , Qureshi A. R. , Lamb K. , Heimbürger O. , Bárány P. , Radhakrishnan K. , Lindholm B. , Soveri I. , Nordfors L. , Shiels P. G. 
Published: February 2008

Abstract.Introduction.  Chronic kidney disease (CKD) predisposes to a 10‐ to 20‐fold increased cardiovascular risk. Patients undergo accelerated atherogenesis and vascular ageing. We investigated whether telomere attrition, a marker of cell senescence, contributes to this increased mortality risk.Methods.  This is a cross‐sectional study in prevalent haemodialysis patients [n = 175; 98 Males; median (range) age: 66 (23–86) years]. Biochemical markers of oxidative stress and inflammatory status were measured in relation to the patient’s leucocyte telomere length. Overall mortality was assessed after a median of 31 (range 2–42) months.Results.  Telomere length was shorter in CKD men, despite women being older (average ± SD 6.41 ± 1.23 vs. 6.96 ± 1.48 kb, P = 0.002). Telomere length was associated with age (rho = −0.18, P = 0.01), fetuin‐A (rho = 0.26, P = 0.0004), high‐sensitivity C‐reactive protein (rho = −0.21, P = 0.005) and IL‐6 (rho = −0.17, P = 0.02). In a multivariate logistic regression (pseudo r2 = 0.14), telomere length was associated with age >65 years (odds ratio: 2.11; 95% CI: 1.10, 4.06), sex (2.01; 1.05, 3.86), fetuin‐A (1.85; 0.97, 3.50) and white blood cell count (2.04; 1.02, 4.09). Receiver operating characteristic curves identified a telomere length < 6.28 kb as a fair predictor of mortality. Finally, reduced telomere length was associated with increased mortality, independently of age, gender and inflammation (likelihood ratio 41.6, P < 0.0001), but dependently on fetuin‐A levels.Conclusion.  Age and male gender seem to be important contributors to reduced telomere length in CKD patients, possibly via persistent inflammation. Reduced telomere length also contributes to the mortality risk of these patients through pathways that could involve circulating levels of fetuin‐A.
Acceptability of blood and blood substitutes
Authors: Ferguson E. , Prowse C. , Townsend E. , Spence A. , Hilten J. A. van , Lowe K. 
Published: February 2008

Abstract.Alternatives to donor blood have been developed in part to meet increasing demand. However, new biotechnologies are often associated with increased perceptions of risk and low acceptance. This paper reviews developments of alternatives and presents data, from a field‐based experiment in the UK and Holland, on the risks and acceptance of donor blood and alternatives (chemical, genetically modified and bovine). UK groups perceived all substitutes as riskier than the Dutch. There is a negative association between perceived risk and acceptability. Solutions to increasing acceptance are discussed in terms of implicit attitudes, product naming and emotional responses.
Characterization of novel mutations in the catalytic domain of the PCSK9 gene
Authors: Cameron J. , Holla Ø. L. , Laerdahl J. K. , Kulseth M. A. , Ranheim T. , Rognes T. , Berge K. E. , Leren T. P. 
Published: February 2008

Abstract.Objectives.  To expand our understanding of the structure and function of proprotein convertase subtilisin/kexin type 9 (PCSK9) by studying how naturally occurring mutations in PCSK9 disrupt the function of PCSK9.Design.  Mutations in PCSK9 were identified by sequencing of DNA from subjects with hypo‐ or hypercholesterolemia. The effect of the identified mutations on the autocatalytic cleavage and secretion of PCSK9, as well as the effect on PCSK9‐mediated degradation of the low density lipoprotein receptors, were determined in HepG2 or HEK293 cells transiently transfected with mutant PCSK9‐containing plasmids. The findings were collated to the clinical characteristics of the subjects possessing these mutations, and the phenotypic effects were analysed in terms of available structural data for PCSK9.Results.  Five novel mutations in PCSK9 were identified. Mutation R215H was a gain‐of‐function mutation which causes hypercholesterolemia. Mutation G236S and N354I were loss‐of‐function mutations due to failure to exit the endoplasmic reticulum or failure to undergo autocatalytic cleavage, respectively. Mutations A245T and R272Q were most likely normal genetic variants. By comparing the number of patients with gain‐of‐function mutations in PCSK9 with the number of familial hypercholesterolemia heterozygotes among subjects with hypercholesterolemia, the prevalence of subjects with gain‐of‐function mutations in PCSK9 in Norway can be estimated to one in 15 000.Conclusion.  This study has provided novel information about the structural requirements for the normal function of PCSK9. However, more studies are needed to determine the mechanisms by which gain‐of‐function mutations in PCSK9 cause hypercholesterolemia.
Bird hosts, blood parasites and their vectors — associations uncovered by molecular analyses of blackfly blood meals
Authors: HELLGREN O. , BENSCH S. , MALMQVIST B. 
Published: February 2008

AbstractThe level of host specificity of blood‐sucking invertebrates may have both ecological and evolutionary implications for the parasites they are transmitting. We used blood meals from wild‐caught blackflies for molecular identification of parasites and hosts to examine patterns of host specificity and how these may affect the transmission of avian blood parasites of the genus Leucocytozoon. We found that five different species of ornithophilic blackflies preferred different species of birds when taking their blood meals. Of the blackflies that contained avian blood meals, 62% were infected with Leucocytozoon parasites, consisting of 15 different parasite lineages. For the blackfly species, there was a significant association between the host width (measured as the genetic differentiation between the used hosts) and the genetic similarity of the parasites in their blood meals. The absence of similar parasite in blood meals from blackflies with different host preferences is interpreted as a result of the vector–host associations. The observed associations between blackfly species and host species are therefore likely to hinder parasites to be transmitted between different host‐groups, resulting in ecologically driven associations between certain parasite lineages and hosts species.
Lactococcus lactis produces short‐chain quinones that cross‐feed Group B Streptococcus to activate respiration growth
Authors: Rezaïki Lahcen , Lamberet Gilles , Derré Aurélie , Gruss Alexandra , Gaudu Philippe 
Published: February 2008

SummaryQuinones are essential components of the respiration chain that shuttle electrons between oxidoreductases. We characterized the quinones synthesized by Lactococcus lactis, a fermenting bacterium that activates aerobic respiration when a haem source is provided. Two distinct subgroups were characterized: Menaquinones (MK) MK‐8 to MK‐10, considered as hallmarks of L. lactis, are produced throughout growth. MK‐3 and demethylMK‐3 [(D)MK‐3] are newly identified and are present only late in growth. Production of (D)MK‐3 was conditional on the carbon sugar and on the presence of carbon catabolite regulator gene ccpA. Electron flux driven by both (D)MK fractions was shared between the quinol oxidase and extracellular acceptors O2, iron and, with remarkable efficiency, copper. Purified (D)MK‐3, but not MK‐8–10, complemented a menB defect in L. lactis. We previously showed that a respiratory metabolism is activated in Group B Streptococcus (GBS) by exogenous haem and MK, and that this activity is implicated in virulence. Here we show that growing lactococci donate (D)MK to GBS to activate respiration and stimulate growth of this opportunist pathogen. We propose that conditions favouring (D)MK production in dense microbial ecosystems, as present in the intestinal tract, could favour implantation of (D)MK‐scavengers like GBS within the complex.
Biosynthesis and IroC‐dependent export of the siderophore salmochelin are essential for virulence of Salmonella enterica serovar Typhimurium
Authors: Crouch Marie‐Laure V. , Castor Margaret , Karlinsey Joyce E. , Kalhorn Thomas , Fang Ferric C. 
Published: February 2008

SummaryIn response to iron deprivation, Salmonella enterica serovar Typhimurium secretes two catecholate‐type siderophores, enterobactin and its glucosylated derivative salmochelin. Although the systems responsible for enterobactin synthesis and acquisition are well characterized, the mechanisms of salmochelin secretion and acquisition, as well as its role in Salmonella virulence, are incompletely understood. Herein we show by liquid chromatography‐mass spectrometry analysis of culture supernatants from wild type and isogenic mutant bacterial strains that the Major Facilitator Superfamily pump EntS is the major exporter of enterobactin and the ABC transporter IroC exports both salmochelin and enterobactin. Growth promotion experiments demonstrate that IroC is not required for utilization of Fe‐enterobactin or Fe‐salmochelin, as had been previously suggested, but the ABC transporter protein FepD is required for utilization of both siderophores. Salmonella mutants deficient in salmochelin synthesis or secretion exhibit reduced virulence during systemic infection of mice.
Ypt32p and Mlc1p bind within the vesicle binding region of the class V myosin Myo2p globular tail domain
Authors: Casavola Elena Caroli , Catucci Alessandro , Bielli Pamela , Di Pentima Alessio , Porcu Giampiero , Pennestri Matteo , Cicero Daniel O. , Ragnini‐Wilson Antonella 
Published: February 2008

SummaryMyosin V is an actin‐based motor essential for a variety of cellular processes including skin pigmentation, cell separation and synaptic transmission. Myosin V transports organelles, vesicles and mRNA by binding, directly or indirectly, to cargo‐bound receptors via its C‐terminal globular tail domain (GTD). We have used the budding yeast myosin V Myo2p to shed light on the mechanism of how Myo2p interacts with post‐Golgi carriers. We show that the Rab/Ypt protein Ypt32p, which associates with membranes of the trans‐Golgi network, secretory vesicles and endosomes and is related to the mammalian Rab11, interacts with the Myo2p GTD within a region previously identified as the ‘vesicle binding region’. Furthermore, we show that the essential myosin light chain 1 (Mlc1p), required for vesicle delivery at the mother‐bud neck during cytokinesis, binds to the Myo2p GTD in a region overlapping that of Ypt32p. Our data are consistent with a role of Ypt32p and Mlc1p in regulating the interaction of post‐Golgi carriers with Myo2p subdomain II.
Dissecting the components of quinine accumulation in Plasmodium falciparum
Authors: Sanchez Cecilia P. , Stein Wilfred D. , Lanzer Michael 
Published: February 2008

SummaryAlthough quinine, the active ingredient of chinchona bark, has been used in the treatment of malaria for several centuries, there is little information regarding the interactions of this drug with the human malaria parasite Plasmodium falciparum. To better understand quinine's mode of action and the mechanism underpinning reduced responsiveness, we have investigated the factors that contribute to quinine accumulation by parasites that differ in their susceptibility to quinine. Interestingly, passive distribution, in accordance with the intracellular pH gradients, and intracellular binding could account for only a small fraction of the high amount of quinine accumulated by the parasites investigated. The results of trans‐stimulation kinetics suggest that high accumulation of quinine is brought about by a carrier‐mediated import system. This import system seems to be weakened in parasites with reduced quinine susceptibility. Other data show that polymorphisms within PfCRT are causatively linked with an increased verapamil‐sensitive quinine efflux that, depending on the genetic background, resulted in reduced quinine accumulation. The polymorphisms within PfMDR1 investigated did not affect quinine accumulation. Our data are consistent with the model that several factors, including acidotropic trapping, binding to intracellular sites and carrier‐mediated import and export transport systems, contribute to steady‐state intracellular quinine accumulation.
Regulation of quinone detoxification by the thiol stress sensing DUF24/MarR‐like repressor, YodB in Bacillus subtilis
Authors: Leelakriangsak Montira , Huyen Nguyen Thi Thu , Töwe Stefanie , Van Duy Nguyen , Becher Dörte , Hecker Michael , Antelmann Haike , Zuber Peter 
Published: February 2008

SummaryRecently, we showed that the MarR‐type repressor YkvE (MhqR) regulates multiple dioxygenases/glyoxalases, oxidoreductases and the azoreductase encoding yvaB (azoR2) gene in response to thiol‐specific stress conditions, such as diamide, catechol and 2‐methylhydroquinone (MHQ). Here we report on the regulation of the yocJ (azoR1) gene encoding another azoreductase by the novel DUF24/MarR‐type repressor, YodB after exposure to thiol‐reactive compounds. DNA binding activity of YodB is directly inhibited by thiol‐reactive compounds in vitro. Mass spectrometry identified YodB‐Cys‐S‐adducts that are formed upon exposure of YodB to MHQ and catechol in vitro. This confirms that catechol and MHQ are auto‐oxidized to toxic ortho‐ and para‐benzoquinones which act like diamide as thiol‐reactive electrophiles. Mutational analyses further showed that the conserved Cys6 residue of YodB is required for optimal repression in vivo and in vitro while substitution of all three Cys residues of YodB affects induction of azoR1 transcription. Finally, phenotype analyses revealed that both azoreductases, AzoR1 and AzoR2 confer resistance to catechol, MHQ, 1,4‐benzoquinone and diamide. Thus, both azoreductases that are controlled by different regulatory mechanisms have common functions in quinone and azo‐compound reduction to protect cells against the thiol reactivity of electrophiles.
The divisomal protein DivIB contains multiple epitopes that mediate its recruitment to incipient division sites
Authors: Wadsworth Kimberly D. , Rowland Susan L. , Harry Elizabeth J. , King Glenn F. 
Published: February 2008

SummaryBacterial cytokinesis is orchestrated by an assembly of essential cell division proteins that form a supramolecular structure known as the divisome. DivIB and its orthologue FtsQ are essential members of the divisome in Gram‐positive and Gram‐negative bacteria respectively. DivIB is a bitopic membrane protein composed of an N‐terminal cytoplasmic domain, a single‐pass transmembrane domain, and a C‐terminal extracytoplasmic region comprised of three separate protein domains. A molecular dissection approach was used to determine which of these domains are essential for recruitment of DivIB to incipient division sites and for its cell division functions. We show that DivIB has three molecular epitopes that mediate its localization to division septa; two epitopes are encoded within the extracytoplasmic region while the third is located in the transmembrane domain. It is proposed that these epitopes represent sites of interaction with other divisomal proteins, and we have used this information to develop a model of the way in which DivIB and FtsQ are integrated into the divisome. Remarkably, two of the three DivIB localization epitopes are dispensable for vegetative cell division; this suggests that the divisome is assembled using a complex network of protein–protein interactions, many of which are redundant and likely to be individually non‐essential.
The Monitor project: rotation of low-mass stars in NGC 2362 – testing the disc regulation paradigm at 5 Myr
Authors: Irwin Jonathan , Hodgkin Simon , Aigrain Suzanne , Bouvier Jerome , Hebb Leslie , Irwin Mike , Moraux Estelle 
Published: February 2008

Abstract
We report on the results of a time-series photometric survey of NGC 2362, carried out using the CTIO 4-m Blanco telescope and Mosaic-II detector as part of the Monitor project. Rotation periods were derived for 271 candidate cluster members over the mass range 0.1 ≲M/M⊙≲ 1.2. The rotation period distributions show a clear mass-dependent morphology, qualitatively similar to that in NGC 2264, as would be expected from the age of this cluster. Using models of angular momentum evolution, we show that angular momentum losses over the ∼1–5 Myr age range appear to be needed in order to reproduce the evolution of the slowest rotators in the sample from the ONC to NGC 2362, as found by many previous studies. By incorporating Spitzer IRAC mid-infrared (mid-IR) measurements, we found that three to four objects showing mid-IR excesses indicative of the presence of circumstellar discs were all slow rotators, as would be expected in the disc regulation paradigm for early pre-main-sequence angular momentum evolution, but this result is not statistically significant at present, given the extremely limited sample size.
A comparison of ammonium, nitrate and proton net fluxes along seedling roots of Douglas‐fir and lodgepole pine grown and measured with different inorganic nitrogen sources
Authors: HAWKINS B. J. , BOUKCIM H. , PLASSARD C. 
Published: February 2008

ABSTRACTSignificant spatial variability in NH4+, NO3− and H+ net fluxes was measured in roots of young seedlings of Douglas‐fir (Pseudotsuga menziesii) and lodgepole pine (Pinus contorta) with ion‐selective microelectrodes. Seedlings were grown with NH4+, NO3−, NH4NO3 or no nitrogen (N), and were measured in solutions containing one or both N ions, or no N in a full factorial design. Net NO3− and NH4+ uptake and H+ efflux were greater in Douglas‐fir than lodgepole pine and in roots not exposed to N in pretreatment. In general, the rates of net NH4+ uptake were the same in the presence or absence of NO3−, and vice versa. The highest NO3− influx occurred 0–30 mm from the root apex in Douglas‐fir and 0–10 mm from the apex in lodgepole pine. Net NH4+ flux was zero or negative (efflux) at Douglas‐fir root tips, and the highest NH4+ influx occurred 5–20 mm from the root tip. Lodgepole pine had some NH4+ influx at the root tips, and the maximum net uptake 5 mm from the root tip. Net H+ efflux was greatest in the first 10 mm of roots of both species. This study demonstrates that nutrient uptake by conifer roots can vary significantly across different regions of the root, and indicates that ion flux profiles along the roots may be influenced by rates of root growth and maturation.
Expression differences for genes involved in lignin, glutathione and sulphate metabolism in response to cadmium in Arabidopsis thaliana and the related Zn/Cd‐hyperaccumulator Thlaspi caerulescens
Authors: VAN DE MORTEL JUDITH E. , SCHAT HENK , MOERLAND PERRY D. , VAN THEMAAT EMIEL VER LOREN , VAN DER ENT SJOERD , BLANKESTIJN HETTY , GHANDILYAN ARTAK , TSIATSIANI STYLIANI , AARTS MARK G.M. 
Published: February 2008

ABSTRACTCadmium (Cd) is a widespread, naturally occurring element present in soil, rock, water, plants and animals. Cd is a non‐essential element for plants and is toxic at higher concentrations. Transcript profiles of roots of Arabidopsis thaliana (Arabidopsis) and Thlaspi caerulescens plants exposed to Cd and zinc (Zn) are examined, with the main aim to determine the differences in gene expression between the Cd‐tolerant Zn‐hyperaccumulator T. caerulescens and the Cd‐sensitive non‐accumulator Arabidopsis. This comparative transcriptional analysis emphasized the role of genes involved in lignin, glutathione and sulphate metabolism. Furthermore the transcription factors MYB72 and bHLH100 were studied for their involvement in metal homeostasis, as they showed an altered expression after exposure to Cd. The Arabidopsis myb72 knockout mutant was more sensitive to excess Zn or iron (Fe) deficiency than wild type, while Arabidopsis transformants overexpressing bHLH100 showed increased tolerance to high Zn and nickel (Ni) compared to wild‐type plants, confirming their role in metal homeostasis in Arabidopsis.