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21.
García-Olmos L Salvador CH Alberquilla Á Lora D Carmona M García-Sagredo P Pascual M Muñoz A Monteagudo JL García-López F 《PloS one》2012,7(2):e32141
Introduction
Healthcare management is oriented toward single diseases, yet multimorbidity is nevertheless the rule and there is a tendency for certain diseases to occur in clusters. This study sought to identify comorbidity patterns in patients with chronic diseases, by reference to number of comorbidities, age and sex, in a population receiving medical care from 129 general practitioners in Spain, in 2007.Methods
A cross-sectional study was conducted in a health-area setting of the Madrid Autonomous Region (Comunidad Autónoma), covering a population of 198,670 individuals aged over 14 years. Multiple correspondences were analyzed to identify the clustering patterns of the conditions targeted.Results
Forty-two percent (95% confidence interval [CI]: 41.8–42.2) of the registered population had at least one chronic condition. In all, 24.5% (95% CI: 24.3–24.6) of the population presented with multimorbidity.In the correspondence analysis, 98.3% of the total information was accounted for by three dimensions. The following four, age- and sex-related comorbidity patterns were identified: pattern B, showing a high comorbidity rate; pattern C, showing a low comorbidity rate; and two patterns, A and D, showing intermediate comorbidity rates.Conclusions
Four comorbidity patterns could be identified which grouped diseases as follows: one showing diseases with a high comorbidity burden; one showing diseases with a low comorbidity burden; and two showing diseases with an intermediate comorbidity burden. 相似文献22.
23.
Using ectomycorrhizal root tip morphotyping (anatomical and morphological identification), molecular analysis (internal transcribed
spacer region amplification and sequencing), and fruitbody sampling, we assessed diversity and composition of the ectomycorrhizal
fungal community colonizing juvenile Pinus pinaster Ait. under natural conditions in NW Spain. Overall, we found 15 Basidiomycetes and two Ascomycetes. Members of the family
Thelephoraceae represented up to 59.4% of the samples. The most frequent species was Tomentella sublilacina followed by Thelephora terrestris, Russula drimeia, Suillus bovinus, and Paxillus involutus, while the less frequent were Pseudotomentella tristis, Lactarius subdulcis, Russula ochroleuca, and Entoloma conferendum. From October 2007 to June 2008, we sampled 208 sporocarps belonging to seven genera and nine species: Thelephora terrestris, Paxillus involutus, Suillus bovinus, Xerocomus badius, Scleroderma verrucosum, Amanita gemmata, A. rubescens, Amanita sp., and Russula sp. The species belonging to the genus Amanita, X. badius and S. verrucosum were not found on root samples. By comparing our results with a bibliographic review of papers published from 1922 to 2006,
we found five genera and six species which have not been previously reported in symbiosis with P. pinaster. This is the first time that the diversity of the ectomycorrhizal fungal community associated with P. pinaster was investigated using molecular techniques. Considering that only 38% of the genera found by sequencing were found as fruitbodies,
we conclude that integrating morphotyping and sporocarps surveys with molecular analysis of ectomycorrhizas is important to
documenting the ectomycorrhizal fungus community.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
24.
Validation of photo‐identification as a mark–recapture method in the spotted eagle ray Aetobatus narinari 下载免费PDF全文
M. S. González‐Ramos A. Santos‐Moreno E. F. Rosas‐Alquicira G. Fuentes‐Mascorro 《Journal of fish biology》2017,90(3):1021-1030
The spotted eagle ray Aetobatus narinari is characterized by pigmentation patterns that are retained for up to 3·5 years. These pigmentations can be used to identify individuals through photo‐identification. Only one study has validated this technique, but no study has estimated the percentage of correct identification of the rays using this technique. In order to carry out demographic research, a reliable photographic identification technique is needed. To achieve this validation for A. narinari, a double‐mark system was established over 11 months and photographs of the dorsal surface of 191 rays were taken. Three body parts with distinctive natural patterns were analysed (dorsal surface of the cephalic region, dorsal surface of the pectoral fins and dorsal surface of the pelvic fins) in order to determine the body part that could be used to give the highest percentage of correct identification. The dorsal surface of the pectoral fins of A. narinari provides the most accurate photo‐identification to distinguish individuals (88·2%). 相似文献
25.
Saladié M Rose JK Cosgrove DJ Catalá C 《The Plant journal : for cell and molecular biology》2006,47(2):282-295
Xyloglucan endotransglucosylase/hydrolases (XTHs) are cell wall-modifying enzymes that align within three or four distinct phylogenetic subgroups. One explanation for this grouping is association with different enzymic modes of action, as XTHs can have xyloglucan endotransglucosylase (XET) or endohydrolase (XEH) activities. While Group 1 and 2 XTHs predominantly exhibit XET activity, to date the activity of only one member of Group 3 has been reported: nasturtium TmXH1, which has a highly specialized function and hydrolyses seed-storage xyloglucan rather than modifying cell wall structure. Tomato fruit ripening was selected as a model to test the hypothesis that preferential XEH activity might be a defining characteristic of Group 3 XTHs, which would be expressed during processes where net xyloglucan depolymerization occurs. Database searches identified 25 tomato XTHs, and one gene (SlXTH5) was of particular interest as it aligned within Group 3 and was expressed abundantly during ripening. Recombinant SlXTH5 protein acted primarily as a transglucosylase in vitro and depolymerized xyloglucan more rapidly in the presence than in the absence of xyloglucan oligosaccharides (XGOs), indicative of XET activity. Thus, there is no correlation between the XTH phylogenetic grouping and the preferential enzymic activities (XET or XEH) of the proteins in those groups. Similar analyses of SlXTH2, a Group 2 tomato XTH, and nasturtium seed TmXTH1 revealed a spectrum of modes of action, suggesting that all XTHs have the capacity to function in both modes. The biomechanical properties of plant walls were unaffected by incubation with SlXTH5, with or without XGOs, suggesting that XTHs do not represent primary cell wall-loosening agents. The possible roles of SlXTH5 in vivo are discussed. 相似文献
26.
Cristina Peligero Jordi Argilaguet Roberto Güerri-Fernandez Berta Torres Carmen Ligero Pilar Colomer Montserrat Plana Hernando Knobel Felipe García Andreas Meyerhans 《PLoS pathogens》2015,11(12)
Blocking the PD-1/PD-L1 pathway has emerged as a potential therapy to restore impaired immune responses in human immunodeficiency virus (HIV)-infected individuals. Most reports have studied the impact of the PD-L1 blockade on effector cells and neglected possible effects on regulatory T cells (Treg cells), which play an essential role in balancing immunopathology and antiviral effector responses. The aim of this study was to define the consequences of ex vivo PD-L1 blockade on Treg cells from HIV-infected individuals. We observed that HIV infection led to an increase in PD-1+ and PD-L1+ Treg cells. This upregulation correlated with disease progression and decreased under antiretroviral treatment. Treg cells from viremic individuals had a particularly high PD-1 expression and impaired proliferative capacity in comparison with Treg cells from individuals under antiretroviral treatment. PD-L1 blockade restored the proliferative capacity of Treg cells from viremic individuals but had no effect on its suppressive capacity. Moreover, it increased the viral production in cell cultures from viremic individuals. This increase in viral production correlated with an increase in Treg cell percentage and a reduction in the CD4/Treg and CD8/Treg cell ratios. In contrast to the effect of the PD-L1 blockade on Treg cells from viremic individuals, we did not observe a significant effect on the proliferative capacity of Treg cells from individuals in whom viremia was controlled (either spontaneously or by antiretroviral treatment). However, PD-L1 blockade resulted in an increased proliferative capacity of HIV-specific-CD8 T cells in all subjects. Taken together, our findings suggest that manipulating PD-L1 in vivo can be expected to influence the net gain of effector function depending on the subject’s plasma viremia. 相似文献
27.
Federica Battistini Pablo D. Dans Montserrat Terrazas Chiara L. Castellazzi Guillem Portella Mireia Labrador Núria Villegas Isabelle Brun-Heath Carlos Gonzlez Modesto Orozco 《PLoS computational biology》2021,17(11)
We present a comprehensive, experimental and theoretical study of the impact of 5-hydroxymethylation of DNA cytosine. Using molecular dynamics, biophysical experiments and NMR spectroscopy, we found that Ten-Eleven translocation (TET) dioxygenases generate an epigenetic variant with structural and physical properties similar to those of 5-methylcytosine. Experiments and simulations demonstrate that 5-methylcytosine (mC) and 5-hydroxymethylcytosine (hmC) generally lead to stiffer DNA than normal cytosine, with poorer circularization efficiencies and lower ability to form nucleosomes. In particular, we can rule out the hypothesis that hydroxymethylation reverts to unmodified cytosine physical properties, as hmC is even more rigid than mC. Thus, we do not expect dramatic changes in the chromatin structure induced by differences in physical properties between d(mCpG) and d(hmCpG). Conversely, our simulations suggest that methylated-DNA binding domains (MBDs), associated with repression activities, are sensitive to the substitution d(mCpG) ➔ d(hmCpG), while MBD3 which has a dual activation/repression activity is not sensitive to the d(mCpG) d(hmCpG) change. Overall, while gene activity changes due to cytosine methylation are the result of the combination of stiffness-related chromatin reorganization and MBD binding, those associated to 5-hydroxylation of methylcytosine could be explained by a change in the balance of repression/activation pathways related to differential MBD binding. 相似文献
28.
Chimpanzee research plays a central role in the discussions of conflict negotiation. Reconciliation, or the attraction and
affiliation of former opponents following conflict, has been proposed as a central element of conflict negotiation in chimpanzees
and various other taxa. In an attempt to expand the database of chimpanzee conflict resolution, conflict and post-conflict
behavior were recorded for a small group of socially housed chimpanzees at the Chimpanzee and Human Communication Institute,
at Central Washington University. Data were collected over six 6-week periods between 1997 and 2000, for a total of 840 hours
of observation, resulting in a substantial post-conflict (PC) and matched control (MC) data set. The data demonstrate this
group’s tendencies to maintain visual contact and closer proximity after conflicts. Dyadic corrected conciliatory tendencies
ranged between 0 – 37.5% and averaged 17.25% across all dyads. Individual corrected conciliatory tendencies ranged between
5.8 and 32%. The results of this study combined with recent publications on captive and free-ranging chimpanzee post-conflict
behavior suggest that variation in post-conflict behavior may be important to our understanding of chimpanzee conflict negotiation,
and may also have implications for the design and management of captive chimpanzee enclosures and social groups, respectively. 相似文献
29.
Victor Neira Peter Rabinowitz Aaron Rendahl Blanca Paccha Shawn G. Gibbs Montserrat Torremorell 《PloS one》2016,11(1)
Indirect transmission of influenza A virus (IAV) in swine is poorly understood and information is lacking on levels of environmental exposure encountered by swine and people during outbreaks of IAV in swine barns. We characterized viral load, viability and persistence of IAV in air and on surfaces during outbreaks in swine barns. IAV was detected in pigs, air and surfaces from five confirmed outbreaks with 48% (47/98) of oral fluid, 38% (32/84) of pen railing and 43% (35/82) of indoor air samples testing positive by IAV RT-PCR. IAV was isolated from air and oral fluids yielding a mixture of subtypes (H1N1, H1N2 and H3N2). Detection of IAV RNA from air was sustained during the outbreaks with maximum levels estimated between 7 and 11 days from reported onset. Our results indicate that during outbreaks of IAV in swine, aerosols and surfaces in barns contain significant levels of IAV potentially representing an exposure hazard to both swine and people. 相似文献
30.