188 research outputs found

    Prospective study of urinary tract infection surveillance after kidney transplantation

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    <p>Abstract</p> <p>Background</p> <p>Urinary tract infection (UTI) remains one of the main complications after kidney transplantation and it has serious consequences.</p> <p>Methods</p> <p>Fifty-two patients with kidney transplantation were evaluated for UTI at 3-145 days (mean 40.0 days) after surgery.. Forty-two received a graft from a live donor and 10 from a deceased donor. There were 22 female and 30 male patients, aged 11-47 years. Microscopic examinations, leukocyte esterase stick, and urinary culture were performed every third day and weekly after hospitalization. A positive culture was consider when patients presented bacterial counts up to 10<sup>5</sup> counts.</p> <p>Results</p> <p>UTI developed in 19/52 (37%) patients at 3-75 days (mean 19.5 days after transplantation. Recurrent infection was observed in 7/52 (13.4%) patients at days 17-65. UTI was more frequent in patients who received deceased grafts compared with live grafts (7/10, 70% <it>vs</it>. 12/42, 28%; p < 0.007). Female patients were more susceptible than male (11/22, 50% <it>vs</it>. 8/22, 36.35%; p < 0.042). Five-year survival rate was 94.5% (49/52 patients). Kidney Graft exit update is 47/52 (90.2%), and there were no significant differences between graft rejection and UTI (p = 0.2518). Isolated bacteria were <it>Escherichia coli </it>(31.5%), <it>Candida albicans </it>(21.0%) and <it>Enterococcus </it>spp. (10.5%), followed by <it>Pseudomonas aeruginosa, Klebsiella pneumoniae, Morganella </it><it>morganii, Enterobacter cloacae </it>and <it>Micrococcus </it>spp. Secondary infections were produced by (7/19, 36.8%). <it>Enterococcus </it>spp. (57%), <it>E. coli </it>(28%) and <it>Micrococcus </it>spp. (14.2%). Antibiotic resistance was 22% for ciprofloxacin and 33% for ampicillin. Therapeutic alternatives were aztreonam, trimethoprim-sulfamethoxazole, netilmicin and fosfomycin.</p> <p>Conclusions</p> <p>Surveillance of UTI for the first 3 months is a good option for improving quality of life of kidney transplantation patients and the exit of graft function especially for female patients and those receiving deceased grafts. Antibiograms provided a good therapeutic alternative to patients who presented with UTIs after receiving a kidney allograft.</p

    Effects of lng Mutations on LngA Expression, Processing, and CS21 Assembly in Enterotoxigenic Escherichia coli E9034A

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    Enterotoxigenic Escherichia coli (ETEC) is a major cause of morbidity in children under 5 years of age in low- and middle-income countries and a leading cause of traveler's diarrhea worldwide. The ability of ETEC to colonize the intestinal epithelium is mediated by fimbrial adhesins, such as CS21 (Longus). This adhesin is a type IVb pilus involved in adherence to intestinal cells in vitro and bacterial self-aggregation. Fourteen open reading frames have been proposed to be involved in CS21 assembly, hitherto only the lngA and lngB genes, coding for the major (LngA) and minor (LngB) structural subunit, have been characterized. In this study, we investigated the role of the LngA, LngB, LngC, LngD, LngH, and LngP proteins in the assembly of CS21 in ETEC strain E9034A. The deletion of the lngA, lngB, lngC, lngD, lngH, or lngP genes, abolished CS21 assembly in ETEC strain E9034A and adherence to HT-29 cells was reduced 90%, compared to wild-type strain. Subcellular localization prediction of CS21 proteins was similar to other well-known type IV pili homologues. We showed that LngP is the prepilin peptidase of LngA, and that ETEC strain E9034A has another peptidase capable of processing LngA, although with less efficiency. Additionally, we present immuno-electron microscopy imagens to show that the LngB protein could be localized at the tip of CS21, and probably helps to control CS21 length. In conclusion, our results demonstrate that the LngA, LngB, LngC, LngD, LngH, and LngP proteins are essential for CS21 assembly, as well as for bacterial aggregation and adherence to HT-29 cells

    Functional traits determine plant co-occurrence more than environment or evolutionary relatedness in global drylands

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    Plant–plant interactions are driven by environmental conditions, evolutionary relationships (ER) and the functional traits of the plants involved. However, studies addressing the relative importance of these drivers are rare, but crucial to improve our predictions of the effects of plant–plant interactions on plant communities and of how they respond to differing environmental conditions. To analyze the relative importance of – and interrelationships among – these factors as drivers of plant–plant interactions, we analyzed perennial plant co-occurrence at 106 dryland plant communities established across rainfall gradients in nine countries. We used structural equation modelling to disentangle the relationships between environmental conditions (aridity and soil fertility), functional traits extracted from the literature, and ER, and to assess their relative importance as drivers of the 929 pairwise plant–plant co-occurrence levels measured. Functional traits, specifically facilitated plants’ height and nurse growth form, were of primary importance, and modulated the effect of the environment and ER on plant–plant interactions. Environmental conditions and ER were important mainly for those interactions involving woody and graminoid nurses, respectively. The relative importance of different plant–plant interaction drivers (ER, functional traits, and the environment) varied depending on the region considered, illustrating the difficulty of predicting the outcome of plant–plant interactions at broader spatial scales. In our global-scale study on drylands, plant–plant interactions were more strongly related to functional traits of the species involved than to the environmental variables considered. Thus, moving to a trait-based facilitation/competition approach help to predict that: (1) positive plant–plant interactions are more likely to occur for taller facilitated species in drylands, and (2) plant–plant interactions within woody-dominated ecosystems might be more sensitive to changing environmental conditions than those within grasslands. By providing insights on which species are likely to better perform beneath a given neighbour, our results will also help to succeed in restoration practices involving the use of nurse plants

    Erroneous attribution of relevant transcription factor binding sites despite successful prediction of cis-regulatory modules

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    <p>Abstract</p> <p>Background</p> <p><it>Cis</it>-regulatory modules are bound by transcription factors to regulate gene expression. Characterizing these DNA sequences is central to understanding gene regulatory networks and gaining insight into mechanisms of transcriptional regulation, but genome-scale regulatory module discovery remains a challenge. One popular approach is to scan the genome for clusters of transcription factor binding sites, especially those conserved in related species. When such approaches are successful, it is typically assumed that the activity of the modules is mediated by the identified binding sites and their cognate transcription factors. However, the validity of this assumption is often not assessed.</p> <p>Results</p> <p>We successfully predicted five new <it>cis</it>-regulatory modules by combining binding site identification with sequence conservation and compared these to unsuccessful predictions from a related approach not utilizing sequence conservation. Despite greatly improved predictive success, the positive set had similar degrees of sequence and binding site conservation as the negative set. We explored the reasons for this by mutagenizing putative binding sites in three <it>cis</it>-regulatory modules. A large proportion of the tested sites had little or no demonstrable role in mediating regulatory element activity. Examination of loss-of-function mutants also showed that some transcription factors supposedly binding to the modules are not required for their function.</p> <p>Conclusions</p> <p>Our results raise important questions about interpreting regulatory module predictions obtained by finding clusters of conserved binding sites. Attribution of function to these sites and their cognate transcription factors may be incorrect even when modules are successfully identified. Our study underscores the importance of empirical validation of computational results even when these results are in line with expectation.</p

    Clinical Risk Score to Predict Pathogenic Genotypes in Patients With Dilated Cardiomyopathy

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    Background: Although genotyping allows family screening and influences risk-stratification in patients with nonischemic dilated cardiomyopathy (DCM) or isolated left ventricular systolic dysfunction (LVSD), its result is negative in a significant number of patients, limiting its widespread adoption. Objectives: This study sought to develop and externally validate a score that predicts the probability for a positive genetic test result (G+) in DCM/LVSD. Methods: Clinical, electrocardiogram, and echocardiographic variables were collected in 1,015 genotyped patients from Spain with DCM/LVSD. Multivariable logistic regression analysis was used to identify variables independently predicting G+, which were summed to create the Madrid Genotype Score. The external validation sample comprised 1,097 genotyped patients from the Maastricht and Trieste registries. Results: A G+ result was found in 377 (37%) and 289 (26%) patients from the derivation and validation cohorts, respectively. Independent predictors of a G+ result in the derivation cohort were: family history of DCM (OR: 2.29; 95% CI: 1.73-3.04; P &lt; 0.001), low electrocardiogram voltage in peripheral leads (OR: 3.61; 95% CI: 2.38-5.49; P &lt; 0.001), skeletal myopathy (OR: 3.42; 95% CI: 1.60-7.31; P = 0.001), absence of hypertension (OR: 2.28; 95% CI: 1.67-3.13; P &lt; 0.001), and absence of left bundle branch block (OR: 3.58; 95% CI: 2.57-5.01; P &lt; 0.001). A score containing these factors predicted a G+ result, ranging from 3% when all predictors were absent to 79% when ≄4 predictors were present. Internal validation provided a C-statistic of 0.74 (95% CI: 0.71-0.77) and a calibration slope of 0.94 (95% CI: 0.80-1.10). The C-statistic in the external validation cohort was 0.74 (95% CI: 0.71-0.78). Conclusions: The Madrid Genotype Score is an accurate tool to predict a G+ result in DCM/LVSD

    Surface indicators are correlated with soil multifunctionality in global drylands

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    Multiple ecosystem functions need to be considered simultaneously to manage and protect the several ecosystem services that are essential to people and their environments. Despite this, cost effective, tangible, relatively simple and globally relevant methodologies to monitor in situ soil multifunctionality, that is, the provision of multiple ecosystem functions by soils, have not been tested at the global scale. We combined correlation analysis and structural equation modelling to explore whether we could find easily measured, field-based indicators of soil multifunctionality (measured using functions linked to the cycling and storage of soil carbon, nitrogen and phosphorus). To do this, we gathered soil data from 120 dryland ecosystems from five continents. Two soil surface attributes measured in situ (litter incorporation and surface aggregate stability) were the most strongly associated with soil multifunctionality, even after accounting for geographic location and other drivers such as climate, woody cover, soil pH and soil electric conductivity. The positive relationships between surface stability and litter incorporation on soil multifunctionality were greater beneath the canopy of perennial vegetation than in adjacent, open areas devoid of vascular plants. The positive associations between surface aggregate stability and soil functions increased with increasing mean annual temperature. Synthesis and applications. Our findings demonstrate that a reduced suite of easily measured in situ soil surface attributes can be used as potential indicators of soil multifunctionality in drylands world-wide. These attributes, which relate to plant litter (origin, incorporation, cover), and surface stability, are relatively cheap and easy to assess with minimal training, allowing operators to sample many sites across widely varying climatic areas and soil types. The correlations of these variables are comparable to the influence of climate or soil, and would allow cost-effective monitoring of soil multifunctionality under changing land-use and environmental conditions. This would provide important information for evaluating the ecological impacts of land degradation, desertification and climate change in drylands world-wide.Fil: Eldridge, David J.. University of New South Wales; AustraliaFil: Delgado Baquerizo, Manuel. Universidad Rey Juan Carlos; EspañaFil: Quero, JosĂ© L.. Universidad de CĂłrdoba; EspañaFil: Ochoa, Victoria. Universidad Rey Juan Carlos; España. Universidad de Alicante; EspañaFil: Gozalo, Beatriz. Universidad Rey Juan Carlos; España. Universidad de Alicante; EspañaFil: GarcĂ­a Palacios, Pablo. Universidad Rey Juan Carlos; EspañaFil: Escolar, Cristina. Universidad Rey Juan Carlos; EspañaFil: GarcĂ­a GĂłmez, Miguel. Universidad PolitĂ©cnica de Madrid; EspañaFil: Prina, AnĂ­bal. Universidad Nacional de La Pampa; ArgentinaFil: Bowker, Mathew A.. Northern Arizona University; Estados UnidosFil: Bran, Donaldo Eduardo. Instituto Nacional de TecnologĂ­a Agropecuaria. Centro Regional Patagonia Norte. EstaciĂłn Experimental Agropecuaria San Carlos de Bariloche; ArgentinaFil: Castro, Ignacio. Universidad Experimental SimĂłn RodrĂ­guez; VenezuelaFil: Cea, Alex. Universidad de La Serena; ChileFil: Derak, Mchich. No especifĂ­ca;Fil: Espinosa, Carlos I.. Universidad TĂ©cnica Particular de Loja; EcuadorFil: Florentino, Adriana. Universidad Central de Venezuela; VenezuelaFil: GaitĂĄn, Juan JosĂ©. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Instituto Nacional de TecnologĂ­a Agropecuaria. Centro de InvestigaciĂłn de Recursos Naturales. Instituto de Suelos; Argentina. Universidad Nacional de LujĂĄn. Departamento de TecnologĂ­a; ArgentinaFil: Gatica, Mario Gabriel. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂ­sicas y Naturales. Departamento de BiologĂ­a; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - San Juan. Centro de Investigaciones de la Geosfera y Biosfera. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂ­sicas y Naturales. Centro de Investigaciones de la Geosfera y Biosfera; ArgentinaFil: GĂłmez GonzĂĄlez, Susana. Universidad de CĂĄdiz; EspañaFil: Ghiloufi, Wahida. UniversitĂ© de Sfax; TĂșnezFil: Gutierrez, Julio R.. Universidad de La Serena; ChileFil: Guzman, Elizabeth. Universidad TĂ©cnica Particular de Loja; EcuadorFil: HernĂĄndez, Rosa M.. Universidad Experimental SimĂłn RodrĂ­guez; VenezuelaFil: Hughes, Frederic M.. Universidade Estadual de Feira de Santana; BrasilFil: Muiño, Walter. Universidad Nacional de La Pampa; ArgentinaFil: Monerris, Jorge. No especifĂ­ca;Fil: Ospina, Abelardo. Universidad Central de Venezuela; VenezuelaFil: RamĂ­rez, David A.. International Potato Centre; PerĂșFil: Ribas Fernandez, Yanina Antonia. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - San Juan. Centro de Investigaciones de la Geosfera y Biosfera. Universidad Nacional de San Juan. Facultad de Ciencias Exactas FĂ­sicas y Naturales. Centro de Investigaciones de la Geosfera y Biosfera; ArgentinaFil: RomĂŁo, Roberto L.. Universidade Estadual de Feira de Santana; BrasilFil: Torres DĂ­az, Cristian. Universidad del Bio Bio; ChileFil: Koen, Terrance B.. No especifĂ­ca;Fil: Maestre, Fernando T.. Universidad Rey Juan Carlos; España. Universidad de Alicante; Españ

    Soil fungal abundance and plant functional traits drive fertile island formation in global drylands

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    Dryland vegetation is characterized by discrete plant patches that accumulate and capture soil resources under their canopies. These “fertile islands” are major drivers of dryland ecosystem structure and functioning, yet we lack an integrated understanding of the factors controlling their magnitude and variability at the global scale.EEA BarilocheFil: Ochoa-Hueso, RaĂșl. Universidad AutĂłnoma de Madrid. Department of Ecology; EspañaFil: Eldridge, David J. University of New South Wales. School of Biological, Earth and Environmental Sciences; AustraliaFil: Delgado-Baquerizo, Manuel. University of Colorado. Cooperative Institute for Research in Environmental Sciences; Estados Unidos. Universidad Rey Juan Carlos. Escuela Superior de Ciencias Experimentales y TecnologĂ­a. Departamento de BiologĂ­a y GeologĂ­a, FĂ­sica y QuĂ­mica InorgĂĄnica; EspañaFil: Soliveres, Santiago. University of Bern. Institute of Plant Sciences; SuizaFil: Bowker, Matthew A. Northern Arizona University. School of Forestry; Estados UnidosFil: Gross, NicolĂĄs. Universidad Rey Juan Carlos. Escuela Superior de Ciencias Experimentales y TecnologĂ­a. Departamento de BiologĂ­a y GeologĂ­a, FĂ­sica y QuĂ­mica InorgĂĄnica; España. Institut Nationale de la Recherche Agronomique; Francia. UniversitĂ© La Rochelle. Centre d’étude biologique de ChizĂ©; FranciaFil: Le Bagousse-Pinguet, Yoann. Universidad Rey Juan Carlos. Escuela Superior de Ciencias Experimentales y TecnologĂ­a. Departamento de BiologĂ­a y GeologĂ­a, FĂ­sica y QuĂ­mica InorgĂĄnica; EspañaFil: Quero, JosĂ© L. Universidad de CĂłrdoba. Escuela TĂ©cnica Superior de IngenierĂ­a AgronĂłmica y de Montes. Departamento de IngenierĂ­a Forestal: EspañaFil: GarcĂ­a-GĂłmez, Miguel. Universidad Rey Juan Carlos. Escuela Superior de Ciencias Experimentales y TecnologĂ­a. Departamento de BiologĂ­a y GeologĂ­a, FĂ­sica y QuĂ­mica InorgĂĄnica; EspañaFil: Valencia, Enrique. Universidad Rey Juan Carlos. Escuela Superior de Ciencias Experimentales y TecnologĂ­a. Departamento de BiologĂ­a y GeologĂ­a, FĂ­sica y QuĂ­mica InorgĂĄnica; EspañaFil: Arredondo, Tulio. Instituto Potosino de InvestigaciĂłn CientĂ­fica y TecnolĂłgica. DivisiĂłn de Ciencias Ambientales; MĂ©xicoFil: Beinticinco, Laura. Universidad Nacional de La Pampa. Facultad de AgronomĂ­a; ArgentinaFil: Bran, Donaldo Eduardo. Instituto Nacional de TecnologĂ­a Agropecuaria (INTA). EstaciĂłn Experimental Agropecuaria Bariloche; ArgentinaFil: Cea, Alex. Universidad de La Serena. Departamento de BiologĂ­a; ChileFil: Coaguila, Daniel. Instituto de Ensino Superior de Rio Verde; BrasilFil: Dougill, Andrew J. University of Leeds. School of Earth and Environment; Gran BretañaFil: Espinosa, Carlos I. Universidad TĂ©cnica Particular de Loja. Departamento de Ciencias Naturales; EcuadorFil: Gaitan, Juan Jose. Instituto Nacional de TecnologĂ­a Agropecuaria (INTA). Instituto de Suelos; ArgentinaFil: Guuroh, Reginald T. University of Cologne. Botanical Institute. Range Ecology and Range Management Group; Alemania. CSIR-Forestry Research Institute of Ghana; GhanaFil: GuzmĂĄn, Elizabeth. Universidad TĂ©cnica Particular de Loja. Departamento de Ciencias Naturales; EcuadorFil: GutiĂ©rrez, Julio R.. Universidad de La Serena. Departamento de BiologĂ­a; Chile. Centro de Estudios Avanzados en Zonas Áridas (CEAZA); Chile. Instituto de EcologĂ­a y Biodiversidad; ChileFil: HernĂĄndez, Rosa M. Universidad Experimental SimĂłn RodrĂ­guez. Centro de AgroecologĂ­a Tropical. Laboratorio de BiogeoquĂ­mica; VenezuelaFil: Huber-Sannwald, Elisabeth. Instituto Potosino de InvestigaciĂłn CientĂ­fica y TecnolĂłgica. DivisiĂłn de Ciencias Ambientales; MĂ©xicoFil: Jeffries, Thomas. Western Sydney University. Hawkesbury Institute for the Environment; AustraliaFil: LinstĂ€dter, Anja. University of Cologne. Botanical Institute. Range Ecology and Range Management Group; AlemaniaFil: Mau, Rebecca L. Northern Arizona University. Center for Ecosystem Science and Society: Estados UnidosFil: Monerris, Jorge. UniversitĂ© du QuĂ©bec Ă  MontrĂ©al. Pavillon des Sciences Biologiques. DĂ©partement des Sciences Biologiques; CanadĂĄFil: Prina, Anibal. Universidad Nacional de La Pampa. Facultad de AgronomĂ­a; ArgentinaFil: Pucheta, Eduardo. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, FĂ­sicas y Naturales. Departamento de BiologĂ­a; ArgentinaFil: Stavi, Ilan. Dead Sea and Arava Science Center, IsraelFil: Thomas, Andrew. Aberystwyth University. Department of Geography and Earth Sciences; Gran BretañaFil: Zaady, Eli. Agricultural Research Organization. Gilat Research Center. Natural Resources; IsraelFil: Singh, Brajesh K. Western Sydney University. Hawkesbury Institute for the Environment; Australia. Western Sydney University. Global Centre for Land-Based Innovation; AustraliaFil: Maestre, Fernando T. Universidad Rey Juan Carlos. Escuela Superior de Ciencias Experimentales y TecnologĂ­a. Departamento de BiologĂ­a y GeologĂ­a, FĂ­sica y QuĂ­mica InorgĂĄnica; Españ

    Soil fungal abundance and plant functional traits drive fertile island formation in global drylands

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    International audience1.Dryland vegetation is characterised by discrete plant patches that accumulate and capture soil resources under their canopies. These “fertile islands” are major drivers of dryland ecosystem structure and functioning, yet we lack an integrated understanding of the factors controlling their magnitude and variability at the global scale.2.We conducted a standardized field survey across two hundred and thirty-six drylands from five continents. At each site, we measured the composition, diversity and cover of perennial plants. Fertile island effects were estimated at each site by comparing composite soil samples obtained under the canopy of the dominant plants and in open areas devoid of perennial vegetation. For each sample, we measured fifteen soil variables (functions) associated with carbon, nitrogen and phosphorus cycling and used the Relative Interaction Index to quantify the magnitude of the fertile island effect for each function. In eighty sites, we also measured fungal and bacterial abundance (quantitative PCR) and diversity (Illumina MiSeq).3.The most fertile islands, i.e. those where a higher number of functions were simultaneously enhanced, were found at lower-elevation sites with greater soil pH values and sand content under semiarid climates, particularly at locations where the presence of tall woody species with a low specific leaf area increased fungal abundance beneath plant canopies, the main direct biotic controller of the fertile island effect in the drylands studied. Positive effects of fungal abundance were particularly associated with greater nutrient contents and microbial activity (soil extracellular enzymes) under plant canopies.4.Synthesis. Our results show that the formation of fertile islands in global drylands largely depends on: (i) local climatic, topographic and edaphic characteristics, (ii) the structure and traits of local plant communities and (iii) soil microbial communities. Our study also has broad implications for the management and restoration of dryland ecosystems worldwide, where woody plants are commonly used as nurse plants to enhance the establishment and survival of beneficiary species. Finally, our results suggest that forecasted increases in aridity may enhance the formation of fertile islands in drylands worldwide

    Specification of Drosophila Corpora Cardiaca Neuroendocrine Cells from Mesoderm Is Regulated by Notch Signaling

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    Drosophila neuroendocrine cells comprising the corpora cardiaca (CC) are essential for systemic glucose regulation and represent functional orthologues of vertebrate pancreatic α-cells. Although Drosophila CC cells have been regarded as developmental orthologues of pituitary gland, the genetic regulation of CC development is poorly understood. From a genetic screen, we identified multiple novel regulators of CC development, including Notch signaling factors. Our studies demonstrate that the disruption of Notch signaling can lead to the expansion of CC cells. Live imaging demonstrates localized emergence of extra precursor cells as the basis of CC expansion in Notch mutants. Contrary to a recent report, we unexpectedly found that CC cells originate from head mesoderm. We show that Tinman expression in head mesoderm is regulated by Notch signaling and that the combination of Daughterless and Tinman is sufficient for ectopic CC specification in mesoderm. Understanding the cellular, genetic, signaling, and transcriptional basis of CC cell specification and expansion should accelerate discovery of molecular mechanisms regulating ontogeny of organs that control metabolism
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