985 resultados para Interaction Patterns


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Bacterial endotoxin (lipopolysaccharide, LPS) is the major component of the outer leaflet of the outer membrane in gram-negative bacteria. During severe infections, bacteria may reach the blood circuit of humans, and endotoxins may be released from the bacteria due to cell division or cell death. In particular enterobacterial forms of LPS represent extremely strong activator molecules of the human immune system causing a rapid induction of cytokine production in monocytes and macrophages. Various mammalian blood proteins have been documented to display LPS binding activities mediating normally decreasing effects in the biological activity of LPS. In more recent studies, the essential systemic oxygen transportation protein hemoglobin (Hb) has been shown to amplify LPS-induced cytokine production on immune cells. The mechanism responsible for this effect is poorly understood. Here, we characterize the interaction of hemoglobin with LPS by using biophysical methods. The data presented, revealing the changes of the type and size of supramolecular aggregates of LPS in the presence of Hb, allow a better understanding of the hemoglobin-induced increase in bioactivity of LPS.

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The bacteria of the Bacteroides fragilis group are considered important clinical pathogens and they are the most common anaerobes isolated from human endogenous infections. In this study, the susceptibility patterns to antibiotics and metals of 114 species of the B. fragilis group isolated from children with and without diarrhea were determined. Susceptibility was assayed by using an agar dilution method with Wilkins-Chalgren agar. All B. fragilis strains were resistant to lead and nickel, but susceptible to metronidazole and imipenem. beta-lactamase production was detected by using biological and nitrocefin methods, respectively, in 50% and 90.6% of the isolates of children with diarrhea and in 60% and 90% of the isolates of children without diarrhea. Our results show an increase of antibiotics and metals resistance in this microbial group, and a periodic evaluation of the antimicrobial susceptibility is needed. In Brazil, the contamination for antibiotics or metal ions is often observed, and it is suggested an increase the antimicrobial resistance surveillance of this microbial group, mainly those isolated from children's diarrhea.

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Cognitive errors (CE) and coping strategies (CS) are the focus of most cognitive-behavioral treatments for incarcerated child molesters. Several studies have reported differences in CEs and CSs between child molesters and controls. However, the vast majority of these studies assessed cognitive errors and coping using questionnaires, which are known to present a number of important limitations. This pilot study aimed to compare the CEs and CSs of N = 17 incarcerated child abusers and N = 12 controls using observer-rated methods, namely the Cognitive Error Rating Scale (CERS; Drapeau et al., 2005) and the Coping Action Pattern Rating Scale (CAPRS; Perry, Drapeau, & Dunkley, 2005). Results showed that child molesters presented more cognitive errors, in particular positive selective abstraction, and lower coping functioning, such as escape strategies. Treatment and research implications, including the use of observer-rated methods, are discussed.

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PURPOSE: Little is known regarding cannabis administration routes for nonmedical use-that is, its delivery methods (e.g., joints, water pipe, food). Therefore, we examined the prevalence rates of different cannabis delivery methods and assessed the relationship of the distinct administration routes with problematic drug use. Subgroups of cannabis users were also investigated (i.e., "pure" cannabis users, previously described as employing a harmless route of administration, and water pipe users, previously described as using a harmful route of administration). METHODS: As part of the Cohort Study on Substance Use Risk Factors, 1,763 cannabis users answered questions concerning their drug use (i.e., routes of administration, problematic cannabis use, other illicit drug use). Descriptive statistics, latent class analysis, correlations and t-tests were assessed. RESULTS: The main administration route was "joints with tobacco"; other routes of administration had prevalence rates from 23.99% to 38.23%. In addition, increasing the number of administration routes was associated with more problematic cannabis use, as well as heavier illicit drug use. Water pipes without tobacco were especially linked to heavy drug use patterns, whereas "pure" cannabis use seemed less harmful. CONCLUSIONS: Our findings highlighted that diversification in routes of administration can be associated with heavier illicit drug use. This was especially true for water pipe users, whereas "pure" cannabis users, who did not mix cannabis with tobacco, were an exception. Indeed, these results may be useful for future preventive programs, which may need to focus on those who have diversified routes of administration for cannabis.

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This thesis seeks to provide an understanding of contemporary Irish social drinking patterns by conducting a detailed analysis of the evolving sociological theories of alcohol consumption in Ireland. ‘Alcohol is a social drug which, to this day, evokes the divisive moral qualities that originated, or at least were solidified, in the last century with the birth of temperance movements’ (Cassidy, 1997:175). The temperance movement in Ireland under Father Mathew, a legacy which still reverberates in Irish society, served to further ingrain the ‘image of the whisky drinking Irishman’ (Ibid: 17). This is seen in such work as Stivers (1976) who uses sociological labelling theory to provide verification of a deviant Irish status, biologically, socially and culturally predisposed to alcohol. The author argues that these temperance movements sought to remove the linkages of alcohol and “Irishness” but this quasi-stigmatisation process created a “self-fulfilling prophecy”, which further abetted the legitimisation of alcohol within cultural spheres. The tourism industry, in connection with drink manufacturers, has had a monumental role in alcohol’s contemporary position within the upper echelons of Irish culture and heritage. Their hand in the commodification of “Stage Irishy”, seen as “craic”, has further entrenched the links between consumption of alcohol and the consumption of Irish Identity “McGovern, 2002). Furthermore, commercial interests are keen to cash in and maintain the dominance of alcohol in Irish society. This thesis concludes that this factor, in connection with the accelerated modernisation that Ireland has experienced since the mid-nineties, has malleable consequences for Irish society. As Keohane and Kuhling (2007) assert, post-modern consumption patterns of excess and ‘insatiability’ have been introduced into contemporary Irish drinking patterns and are affecting the nature of alcohol consumption in Ireland.This resource was contributed by The National Documentation Centre on Drug Use.

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Background and purpose:  Recent evidence suggests that variation in the SNCA, MAPT, and GSK3B genes interacts in affecting risk for Parkinson disease (PD). In the current study, we attempt to validate previously published findings, evaluating gene-gene interactions between SNCA, MAPT, and GSK3B in association with PD. Methods:  Three Caucasian PD patient-control series from the United States, Ireland, and Norway (combined n = 1020 patients and 1095 controls) were genotyped for SNCA rs356219, MAPT H1/H2-discriminating SNP rs1052553, and GSK3B rs334558 and rs6438552. Results:  Our findings indicate that as previously reported, the SNCA rs356219-G allele and MAPT rs1052553 (H1 haplotype) were both associated with an increased risk of PD, whilst contrary to previous reports, GSK3B variants were not. No pair-wise interaction was observed between SNCA, MAPT, and GSK3B; the risk effects of SNCA rs356219-G and MAPT rs1052553-H1 were seen in a similar manner across genotypes of other variants, with no evidence suggesting synergistic, antagonistic, or deferential effects. Conclusions:  In the Caucasian patient-control series examined, risk for PD was influenced by variation in SNCA and MAPT but not GSK3B. Additionally, those three genes did not interact in determining disease risk.

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Résumé Les agents pathogènes responsables d'infection entraînent chez l'hôte deux types de réponses immunes, la première, non spécifique, dite immunité innée, la seconde, spécifique à l'agent concerné, dite immunité adaptative. L'immunité innée, qui représente la première ligne de défense contre les pathogènes, est liée à la reconnaissance par les cellules de l'hôte de structures moléculaires propres aux micro-organismes (« Pathogen-Associated Molecular Patterns », PAMPs), grâce à des récepteurs membranaires et cytoplasmiques (« Pattern Recognition Receptors », PRRs) identifiant de manière spécifique ces motifs moléculaires. Les récepteurs membranaires impliqués dans ce processus sont dénommés toll-like récepteurs, ou TLRS. Lorsqu'ils sont activés par leur ligand spécifique, ces récepteurs activent des voies de signalisation intracellulaires initiant la réponse inflammatoire non spécifique et visant à éradiquer l'agent pathogène. Les deux voies de signalisation impliquées dans ce processus sont la voie des « Mitogen-Activated Protein Kinases » (MAPKs) et celle du « Nuclear Factor kappaB » (NF-κB), dont l'activation entraîne in fine l'expression de protéines de l'inflammation dénommées cytokines, ainsi que certaines enzymes produisant divers autres médiateurs inflammatoires. Dans certaines situations, cette réponse immune peut être amplifiée de manière inadéquate, entraînant chez l'hôte une réaction inflammatoire systémique exagérée, appelée sepsis. Le sepsis peut se compliquer de dysfonctions d'organes multiples (sepsis sévère), et dans sa forme la plus grave, d'un collapsus cardiovasculaire, définissant le choc septique. La défaillance circulatoire du choc septique touche les vaisseaux sanguins d'une part, le coeur d'autre part, réalisant un tableau de «dysfonction cardiaque septique », dont on connaît mal les mécanismes pathogéniques. Les bactéries à Gram négatif peuvent déclencher de tels phénomènes, notamment en libérant de l'endotoxine, qui active les voies de l'immunité innée par son interaction avec un toll récepteur, le TLR4. Outre l'endotoxine, la plupart des bactéries à Gram négatif relâchent également dans leur environnement une protéine, la flagelline, qui est le constituant majeur du flagelle bactérien, organelle assurant la mobilité de ces micro-organismes. Des données récentes ont indiqué que la flagelline active, dans certaines cellules, les voies de l'immunité innée en se liant au récepteur TLRS. On ne connaît toutefois pas les conséquences de l'interaction flagelline-TLRS sur le développement de l'inflammation et des dysfonctions d'organes au cours du sepsis. Nous avons par conséquent élaboré le présent travail en formulant l'hypothèse que la flagelline pourrait déclencher une telle inflammation et représenter ainsi un médiateur potentiel de la dysfonction d'organes au cours du sepsis à Gram négatif, en nous intéressant plus particulièrement àl'inflammation et à la dysfonction cardiaque. Dans la première partie de ce travail, nous avons étudié les effets de la flagelline sur l'activation du NF-κB et des MAPKs, et sur l'expression de cytokines inflammatoires au niveau du myocarde in vitro (cardiomyocytes en culture) et in vivo (injection de flagelline recombinante à des souris). Nous avons observé tout d'abord que le récepteur TLRS est fortement exprimé au niveau du myocarde. Nous avons ensuite démontré que la flagelline active la voie du NF-κB et des MAP kinases (p38 et JNK), stimule la production de cytokines et de chemokines inflammatoires in vitro et in vivo, et entraîne l'activation de polynucléaires neutrophiles dans le tissu cardiaque in vivo. Finalement, au plan fonctionnel, nous avons pu montrer que la flagelline entraîne une dilatation et une réduction aiguë de la contractilité du ventricule gauche chez la souris, reproduisant les caractéristiques de la dysfonction cardiaque septique. Dans la deuxième partie, nous avons déterminé la distribution du récepteur TLRS dans les autres organes majeurs de la souris (poumon, foie, intestin et rein}, et avons caractérisé dans ces organes l'effet de la flagelline sur l'activation du NF-κB et des MAPKs, l'expression de cytokines, et l'induction de l'apoptose. Nous avons démontré que le TLRS est exprimé de façon constitutive dans ces organes, et que l'injection de flagelline y déclenche les cascades de l'immunité innée et de processus apoptotiques. Finalement, nous avons également déterminé que la flagelline entraîne une augmentation significative de multiples cytokines dans le plasma une à six heures après son injection. En résumé, nos données démontrent que la flagelline bactérienne (a) entraîne une inflammation et une dysfonction importantes du myocarde et (b) active de manière très significative les mécanismes d'immunité innée dans les principaux organes et entraîne une réponse inflammatoire systémique. Par conséquent, la flagelline peut représenter un médiateur puissant de l'inflammation et de la dysfonction d'organes, notamment du coeur, au cours du choc septique déclenché par les bactéries à Gram négatif. Summary Pathogenic microorganisms trigger two kinds of immune responses in the host. The first one is immediate and non-specific and is termed innate immunity, whereas the second one, specifically targeted at the invading agent, is termed adaptative immunity. Innate immunity, which represents the first line of defense against invading pathogens, confers the host the ability to recognize molecular structures common to many microbial pathogens, ("Pathogen-Associated Molecular Patterns", PAMPs), through cytosolic or membrane-associated receptors ("Pattern Recognition Receptors", PRRs), the latter being represented by a family of receptors termed "toll-like receptors or TLRs". Once activated by the binding of their specific ligand, these receptors activate intracellular signaling pathways, which initiate the non-specific inflammatory response aimed at eradicating the pathogens. The two pathways implicated in this process are the mitogen-activated protein kinases (MAPK) and the nuclear factor kappa B (NF-κB) signaling pathways, whose activation elicit in fine the expression of inflammatory proteins termed cytokines, as well as various enzymes producing a wealth of additional inflammatory mediators. In some circumstances, the innate immune response can become amplified and dysregulated, triggering an overwhelming systemic inflammatory response in the host, identified as sepsis. Sepsis can be associated with multiple organ dysfunction (severe sepsis), and in its most severe form, with cardiovascular collapse, defming septic shock. The cardiovascular failure associated with septic shock affects blood vessels as well as the heart, resulting in a particular form of acute heart failure termed "septic cardiac dysfunction ", whose pathogenic mechanisms remain partly undefined. Gram-negative bacteria can initiate such phenomena, notably by releasing lipopolysaccharide (LPS), which activates innate immune signaling by interacting with its specific toll receptor, the TLR4. Besides LPS, most Gram-negative bacteria also release flagellin into their environment, which is the main structural protein of the bacterial flagellum, an appendage extending from the outer bacterial membrane, responsible for the motility of the microorganism. Recent data indicated that flagellin activate immune responses upon binding to its receptor, TLRS, in various cell types. However, the role of flagellin/TLRS interaction in the development of inflammation and organ dysfunction during sepsis is not known. Therefore, we designed the present work to address the hypothesis that flagellin might trigger such inflammatory responses and thus represent a potential mediator of organ dysfunction during Gram-negative sepsis, with a particular emphasis on cardiac inflammation and contractile dysfunction. In the first part of this work, we investigated the effects of flagellin on NF-κB and MAPK activation and the generation of pro-inflammatory mediators within the heart in vitro (cultured cardiomyocytes) and in vivo (injection of recombinant flagellin into mice). We first observed that TLRS protein is strongly expressed by the myocardium. We then demonstrated that flagellin activates NF-κB and MAP kinases (p38 and JNK), upregulates the transcription of pro-inflammatory cytokines and chemokines in vitro and in vivo, and stimulates the activation of polymorphonuclear neutrophils within the heart in vivo. Finally, we demonstrated that flagellin triggers acute cardiac dilation, and a significant reduction of left ventricular contractility, mimicking characteristics of clinical septic cardiac dysfunction. In the second part, we determined the TLRS distribution in other mice major organs (lung, liver, gut and kidney) and we characterized in these organs the effects of flagellin on NF-κB and MAPK activation, on the expression of pro-inflammatory çytokines, and on the induction of apoptosis. We demonstrated that TLRS protein is constitutively expressed and that flagellin activates prototypical innate immune responses and pro-apoptotic pathways in all these organs. Finally, we also observed that flagellin induces a significant increase of multiple cytokines in the plasma from 1 to 6 hours after its intravenous administration. Altogether, these data provide evidence that bacterial flagellin (a) triggers an important inflammatory response and an acute dysfunction of the myocardium, and (b) significantly activates the mechanisms of innate immunity in most major organs and elicits a systemic inflammatory response. In consequence, flagellin may represent a potent mediator of inflammation and multiple organ failure, notably cardiac dysfunction, during Gram-negative septic shock.

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The primary aim of this study was to investigate the effect of different drinking patterns in an Irish population on ability to cope with stress. Coping ability comprised approach coping responses, avoidance coping responses and trait anxiety levels. Coping responses were measured by the coping responses inventory (CRI, Moos, 1993) and trait anxiety by the state-trait anxiety inventory (STAI, Spielberger, 1983). A total of 128 participants took part in the study and were recruited from alcohol treatment centres and the general population.This resource was contributed by The National Documentation Centre on Drug Use.

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Biomphalaria tenagophila is very important for schistosomiasis transmission in Brazil. However its mechanisms of interaction with Schistosoma mansoni are still scantly studied. Since this snail displays strains highly susceptible or completely resistant to the parasite infection, the knowledge of that would be a useful tool to understand the mechanism of snail resistance. Particularly, the Taim strain consistently shows absolute resistance against the trematode, and this resistance is a dominant character. A multidisciplinary research group was created aiming at studying B. tenagophila/S. mansoni interaction. The possibility for applying the knowledge acquired to obtain a biological model for the control of S. mansoni transmission in endemic areas is discussed.

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The complexity of mammalian genome organization demands a complex interplay of DNA and proteins to orchestrate proper gene regulation. CTCF, a highly conserved, ubiquitously expressed protein has been postulated as a primary organizer of genome architecture because of its roles in transcriptional activation/repression, insulation and imprinting. Diverse regulatory functions are exerted through genome wide binding via a central eleven zinc finger DNA binding domain and an array of diverse protein-protein interactions through N- and C- terminal domains. CTCFL has been identified as a paralog of CTCF expressed only in spermatogenic cells of the testis. CTCF and CTCFL have a highly homologous DNA-binding domain, while the flanking amino acid sequences exhibit no significant similarity. Genome- wide mapping of CTCF binding sites has been carried out in many cell types, but no data exist for CTCFL apart from a few identified loci. The lack of high quality antibodies prompted us to generate an endogenously flag-tagged CTCFL mouse model using BAC recombination. IHC staining using anti-flag antibodies confirmed CTCFL localization to type Β spermatogonia and preleptotene spermatocytes and a mutually exclusive pattern of expression with CTCF. ChIP followed by high-throughput sequencing identified 10,382 binding sites showing 70% overlap but representing only 20% of CTCF sites. Consensus sequence analysis identified a significantly longer binding motif with prominently less ambiguity of base calling at every position. The significant difference between CTCF and CTCFL genomic binding patterns proposes that their binding to DNA is differentially regulated. Analysis of CTCFL binding to methylated regions on a genome wide scale identified approximately 1,000 loci. Methylation-independent binding of CTCFL might be at least one of the mechanisms that ensures distinct binding patterns of CTCF and CTCFL since CTCF binding is methylation- sensitive. Co-localization of CTCF with cohesin has been well established and analysis of CTCFL and SMC3 overlap identified around 3,300 binding sites from which two related but distinct consensus sequence motifs were derived. Because virtually all data for cohesin binding originate from mitotically proliferating cells, the anticipated overlap is expected to be considerably higher in meiotic cells. Meiosis-specific cohesin subunit Rec8 is specific for spermatocytes and 6 out of the 12 identified binding sites are also bound by CTCFL. In conclusion, this was the first genome-wide mapping of CTCFL binding sites in spermatocytes, the only cell type where CTCF is not expressed. CTCFL has a unique binding site repertoire distinct from CTCF, binds to methylated sequences and shows a significant overlap with cohesin binding sites. Future efforts will be oriented towards deciphering the role CTCFL plays in conversion of chromatin structure and function from mitotic to meiotic chromosomes. - La complexité de l'organisation du génome des mammifères exige une interaction particulière entre ADN et protéines pour orchestrer une régulation appropriée de l'expression des gènes. CTCFL, une protéine ubiquitaire très conservée, serait le principal organisateur de l'architecture du génome de par son rôle dans l'activation / la répression de la transcription, la protection et la localisation des gènes. Diverses régulations sont opérées, d'une part au travers d'interactions à différents endroits du génome par le biais d'un domaine protéique central de liaison à l'ADN à onze doigts de zinc, et d'autre part par des interactions protéine-protéine variées au niveau de leur domaine N- et C-terminal. CTCFL a été identifié comme un paralogue de CTCF exprimé uniquement dans les cellules spermatiques du testicule. CTCFL et CTCF ont un domaine de liaison à l'ADN très homologue, tandis que les séquences d'acides aminés situées de part et d'autre de ce domaine ne présentent aucune similitude. Une cartographie générale des sites de liaison au CTCF a été réalisée pour de nombreux types cellulaires, mais il n'existe aucune donnée pour CTCFL à l'exception de l'identification de quelques loci. L'absence d'anticorps de bonne qualité nous a conduit à générer un modèle murin portant un CTCFL endogène taggué grâce à un procédé de recombinaison BAC. Une coloration IHC à l'aide d'anticorps anti-FLAG a confirmé la présence de CTCFL au niveau des spermatogonies de type Β et des spermatocytes au stade préleptotène, et une distribution mutuellement exclusive avec CTCF. Une méthode de Chromatine Immunoprecipitation (ChIP) suivie d'un séquençage à haut débit a permis d'identifier 10.382 sites de liaison montrant 70% d'homologie mais ne représentant que 20% des sites CTCF. L'analyse de la séquence consensus révèle un motif de fixation à l'ADN nettement plus long et qui comporte bien moins de bases aléatoires à chaque position nucléotidique. La différence significative entre les séquences génomiques des sites de liaison au CTCF et CTCFL suggère que leur fixation à l'ADN est régulée différemment. Appliquée à l'échelle du génome, l'étude de l'interaction de CTCFL avec des régions méthylées de l'ADN a permis d'identifier environ 1.000 loci. Contrairement à CTCFL, la liaison de CTCF dépend de l'état de méthylation de l'ADN ; cette modification épigénétique constitue donc au moins un des mécanismes de régulation expliquant une localisation de CTCF et CTCFL à des sites distincts du génome. La co- localisation de CTCF avec la cohésine étant établie, l'analyse de la superposition des séquences de CTCFL avec la sous-unité SMC3 identifie environ 3.300 sites de liaison parmi lesquels deux mêmes motifs consensus distincts par leur séquence sont mis en évidence. La presque quasi-totalité des données sur la cohésine ayant été établie à partir de cellules en prolifération mitotique, il est probable que la similitude au sein des séquences consensus soit encore plus grande dans le cas des cellules en méiose. La sous-unité Rec8 de la cohésine propre à l'état de méiose est spécifiquement exprimée dans les spermatocytes. Or 6 des 12 sites de liaison identifiés sont également utilisés par CTCFL. Pour conclure, ce travail constitue la première cartographie à l'échelle du génome des sites de liaison de CTCFL dans les spermatocytes, seul type cellulaire où CTCFL n'est pas exprimé. CTCFL possède un répertoire unique de sites de fixation à l'ADN distinct de CTCF, se lie à des séquences méthylées et présente un nombre important de sites de liaison communs avec la cohésine. Les perspectives futures sont d'élucider le rôle de CTCFL dans le remodelage de la structure de la chromatine et de définir sa fonction dans le processus de méiose.

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The increase in life expectancy that we continue to observe raises a complex set of challenges for policy. Among these challenges is the need to respond to the heterogeneity that remains in life expectancy within the older population. Most important is that life expectancy, even at older ages, differs markedly by socioeconomic position. In addition, despite increases in longevitymany individuals now effectively retire before state pension age and a large proportion of these are dependent on benefit income. In contrast, the contribution by older people to informal careprovision and other services has the potential to provide an important input into society, the economy and their own well-being. A crucial question, therefore, is which sections of the older population will live healthy active lives and which will be dependent on formal and informal sources of support. To answer this, we need to understand how inequalities in health are distributed in the older population and what the underlying causal processes are.

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AimWe take a comparative phylogeographical approach to assess whether three species involved in a specialized oil-rewarding pollination system (i.e. Lysimachia vulgaris and two oil-collecting bees within the genus Macropis) show congruent phylogeographical trajectories during post-glacial colonization processes. Our working hypothesis is that within specialized mutualistic interactions, where each species relies on the co-occurrence of the other for survival and/or reproduction, partners are expected to show congruent evolutionary trajectories, because they are likely to have followed parallel migration routes and to have shared glacial refugia. LocationWestern Palaearctic. MethodsOur analysis relies on the extensive sampling of 104 Western Palaearctic populations (totalling 434, 159 and 74 specimens of Lysimachiavulgaris, Macropiseuropaea and Macropisfulvipes, respectively), genotyped with amplified fragment length polymorphism. Based on this, we evaluated the regional genetic diversity (Shannon diversity and allele rarity index) and genetic structure (assessed using structure, population networks, isolation-by-distance and spatial autocorrelation metrics) of each species. Finally, we compared the general phylogeographical patterns obtained. ResultsContrary to our expectations, the analyses revealed phylogeographical signals suggesting that the investigated organisms demonstrate independent post-glacial trajectories as well as distinct contemporaneous demographic parameters, despite their mutualistic interaction. Main conclusionsThe mutualistic partners investigated here are likely to be experiencing distinct and independent evolutionary dynamics because of their contrasting life-history traits (e.g. dispersal abilities), as well as distinct hubs and migration routes. Such conditions would prevent and/or erase any signature of co-structuring of lineages in space and time. As a result, the lack of phylogeographical congruence driven by differences in life-history traits might have arisen irrespective of the three species having shared similar Pleistocene glacial refugia.

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Breastfeeding has important health benefits for both mother and child. Breastfed babies are less likely to report with gastric, respiratory and urinary tract infections and allergic diseases, while they are also less likely to become obese in later childhood. Improving breastfeeding initiation has become a national priority, and a national target has been set ̢?oto deliver an increase of two percentage points per annum in breastfeeding initiation rate, focusing especially on women from disadvantaged areas̢?. Despite improvements in data quality in previous years, it still remains difficult to construct an accurate and reliable picture of variations and trends in breastfeeding in the East Midlands. It is essential that nationally standardised data collection systems are put in place to enable effective and accurate monitoring and evaluation of breastfeeding status both at a local and national level.

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The antimicrobial susceptibility of 176 unusual non-fermentative gram-negative bacilli (NF-GNB) collected from Latin America region through the SENTRY Program between 1997 and 2002 was evaluated by broth microdilution according to the National Committee for Clinical Laboratory Standards (NCCLS) recommendations. Nearly 74% of the NF-BGN belonged to the following genera/species: Burkholderia spp. (83), Achromobacter spp. (25), Ralstonia pickettii (16), Alcaligenes spp. (12), and Cryseobacterium spp. (12). Generally, trimethoprim/sulfamethoxazole (MIC50, < 0.5 µg/ml) was the most potent drug followed by levofloxacin (MIC50, 0.5 µg/ml), and gatifloxacin (MIC50, 1 µg/ml). The highest susceptibility rates were observed for levofloxacin (78.3%), gatifloxacin (75.6%), and meropenem (72.6%). Ceftazidime (MIC50, 4 µg/ml; 83.1% susceptible) was the most active beta-lactam against B. cepacia. Against Achromobacter spp. isolates, meropenem (MIC50, 0.25 µg/ml; 88% susceptible) was more active than imipenem (MIC50, 2 µg/ml). Cefepime (MIC50, 2 µg/ml; 81.3% susceptible), and imipenem (MIC50, 2 µg/ml; 81.3% susceptible) were more active than ceftazidime (MIC50, >16 µg/ml; 18.8% susceptible) and meropenem (MIC50, 8 µg/ml; 50% susceptible) against Ralstonia pickettii. Since selection of the most appropriate antimicrobial agents for testing and reporting has not been established by the NCCLS for many of NF-GNB species, results from large multicenter studies may help to guide the best empiric therapy.