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71.
Alexander Kotrschal Susanne Trombley Björn Rogell Ioana Brannström Eric Foconi Monika Schmitz Niclas Kolm 《Evolutionary ecology》2014,28(6):1043-1055
It has been suggested that mating behaviours require high levels of cognitive ability. However, since investment into mating and the brain both are costly features, their relationship is likely characterized by energetic trade-offs. Empirical data on the subject remains equivocal. We investigated if early sexual maturation was associated with brain development in Atlantic salmon (Salmo salar), in which males can either stay in the river and sexually mature at a small size (sneaker males) or migrate to the sea and delay sexual maturation until they have grown much larger (anadromous males). Specifically, we tested how sexual maturation may induce plastic changes in brain development by rearing juveniles on either natural or ad libitum feeding levels. After their first season we compared brain size and brain region volumes across both types of male mating tactics and females. Body growth increased greatly across both male mating tactics and females during ad libitum feeding as compared to natural feeding levels. However, despite similar relative increases in body size, early maturing sneaker males maintained larger relative brain size during ad libitum feeding levels as compared to anadromous males and females. We also detected several differences in the relative size of separate brain regions across feeding treatments, sexes and mating strategies. For instance, the relative size of the cognitive centre of the brain, the telencephalon, was largest in sneaker males. Our data support that a large relative brain size is maintained in individuals that start reproduction early also during fast body growth. We propose that the cognitive demands during complex mating behaviours maintain a high level of investment into brain development in reproducing individuals. 相似文献
72.
73.
Background
Poor adherence to isoniazid (INH) preventive therapy (IPT) is an impediment to effective control of latent tuberculosis (TB) infection. TB patients who smoke are at higher risk of latent TB infection, active disease, and TB mortality, and may have lower adherence to their TB medications. The objective of our study was to validate IsoScreen and SmokeScreen (GFC Diagnostics, UK), two point-of-care tests for monitoring INH intake and determining smoking status. The tests could be used together in the same individual to help identify patients with a high-risk profile and provide a tailored treatment plan that includes medication management, adherence interventions, and smoking cessation programs.Methodology/Principal Findings
200 adult outpatients attending the TB and/or the smoking cessation clinic were recruited at the Montreal Chest Institute. Sensitivity and specificity were measured for each test against the corresponding composite reference standard. Test reliability was measured using kappa statistic for intra-rater and inter-rater agreement. Univariate and multivariate logistic regression models were used to explore possible covariates that might be related to false-positive and false-negative test results. IsoScreen had a sensitivity of 93.2% (95% confidence interval [CI] 80.3, 98.2) and specificity of 98.7% (94.8, 99.8). IsoScreen had intra-rater agreement (kappa) of 0.75 (0.48, 0.94) and inter-rater agreement of 0.61 (0.27, 0.90). SmokeScreen had a sensitivity of 69.2% (56.4, 79.8), specificity of 81.6% (73.0, 88.0), intra-rater agreement of 0.77 (0.56, 0.94), and inter-rater agreement of 0.66 (0.42, 0.88). False-positive SmokeScreen tests were strongly associated with INH treatment.Conclusions
IsoScreen had high validity and reliability, whereas SmokeScreen had modest validity and reliability. SmokeScreen tests did not perform well in a population receiving INH due to the association between INH treatment and false-positive SmokeScreen test results. Development of the next generation SmokeScreen assay should account for this potential interference. 相似文献74.
Phylogenetic analysis of the microbial populations in the wild herbivore gastrointestinal tract: insights into an unexplored niche 总被引:5,自引:0,他引:5
Nelson KE Zinder SH Hance I Burr P Odongo D Wasawo D Odenyo A Bishop R 《Environmental microbiology》2003,5(11):1212-1220
At present, there is little information on the phylogenetic diversity of microbial species that inhabit the gastrointestinal tracts of wildlife. To increase understanding in this area, we initiated a characterization of the bacterial diversity in the digestive tracts of three wild African ruminant species namely eland (Taurotragus oryx), Thompson's gazelle (Gazella rufifrons) and Grant's gazelle (Gazella granti), together with a domesticated ruminant species, zebu cattle (Bos indicus), and a non-ruminant species, zebra (Equus quagga). Bacterial diversity was analysed by PCR amplification, sequencing and phylogenetic analysis of 16S ribosomal DNA (rDNA) sequences. A total of 252 full-length 16S rDNA sequences averaging 1,500 base pairs (bp) in length, and an additional 27 partial sequences were obtained and subject to phylogenetic analysis. Using a 98% criterion for similarity, all except for one of the sequences were derived from distinct phylotypes. At least 24 distinct operational taxonomic units (OTU's) could be identified, with the majority of these sequences representing hitherto uncharacterized species and genera. The sequences were generally affiliated with four major bacterial phyla, the majority being members of the Firmicutes (low G+C Gram-positives) related to the genera Clostridium and Ruminococcus. By contrast, with earlier studies using 16S rDNA sequences to assess biodiversity in Bos taurus dairy cattle, Gram-negative bacteria in the Bacteroidales (Prevotella-Bacteroides group) were poorly represented. The lack of redundancy in the 16S rDNA dataset from the five African ungulate species, and the presence of novel sequences not previously described from the gastrointestinal tract of any animal species, highlights the level of diversity that exists in these ecosystems and raises the question as to the functional role of these species in the gastrointestinal tract. 相似文献
75.
Ioana Cristina Constantinescu Gabriel Chi?amera D. Khlur B. Mukhim Costic? Adam 《ZooKeys》2014,(425):1-13
The article describes a new species of the feather mite subfamily Pterodectinae from the Little Spiderhunter Arachnothera longirostra Temminck, 1826 (Passeriformes, Nectariniidae) in India. Pedanodectes angustilobussp. n. differs from all known Pedanodectes species by having opisthosomal lobes short, at base wider than long, roughly rounded apically in males, and strongly elongated and narrowed lobar region with wide terminal appendages in females. A key to species of the genus Pedanodectes is presented. 相似文献
76.
Teodora Ioana Flavia Paunas Kenneth Finne Sabine Leh Hans-Peter Marti Tom Eirik Mollnes Frode Berven Bjørn Egil Vikse 《Clinical proteomics》2017,14(1):30
Background
The clinical course of IgA nephropathy (IgAN) is variable and complement activation may predict prognosis. The present study investigated whether glomerular abundance of complement proteins associates with progression to end-stage renal disease (ESRD) in patients for whom prognosis could not be predicted based on clinical variables.Methods
Based on data from the Norwegian Kidney Biopsy Registry and the Norwegian Renal Registry, three groups were included: IgAN patients with (n = 9) or without (n = 16) progression to ESRD during 10 years, and controls (n = 15) with a normal kidney biopsy. IgAN patients had eGFR > 45 ml/min/1.73 m2 and non-nephrotic proteinuria at time of biopsy. Using stored formalin-fixed paraffin embedded kidney biopsy tissue, about 100 glomerular cross sections were microdissected for each patient. Samples were analyzed by liquid chromatography–tandem mass spectrometry and relative abundances of complement proteins were compared between groups.Results
Proteomic analyses quantified 2018 proteins, of which 28 proteins belong to the complement system. As compared to IgAN patients without progressive disease, glomeruli from patients with progressive IgAN had significantly higher abundance of components of the classical and the terminal complement pathways, and inhibitory factors such as Factor H and factor H related proteins. Abundance of complement proteins classified progressors from non-progressors with an area under ROC curve of 0.91 (p = 0.001). Clinical and morphological data were similar between the two patient groups and could not predict progressive IgAN.Conclusions
In conclusion, higher glomerular abundance of complement proteins was associated with a progressive clinical course in IgAN and are candidate biomarkers to predict prognosis.77.
Lucian Prvulescu Jorge L. Prez‐Moreno Cristian Panaiotu Lucian Drgu Anne Schrimpf Ioana‐Diana Popovici Claudia Zaharia Andrs Weiperth Blanka Gl Christoph D. Schubart Heather Bracken‐Grissom 《Ecology and evolution》2019,9(4):1957-1971
Crayfish can be used as model organisms in phylogeographic and divergence time studies if reliable calibrations are available. This study presents a comprehensive investigation into the phylogeography of the European stone crayfish (Austropotamobius torrentium) and includes samples from previously unstudied sites. Two mitochondrial markers were used to reveal evolutionary relationships among haplogroups throughout the species’ distributional range and to estimate the divergence time by employing both substitution rates and geological calibration methods. Our haplotype network reconstruction and phylogenetic analyses revealed the existence of a previously unknown haplogroup distributed in Romania's Apuseni Mountains. This haplogroup is closely related to others that are endemic in the Dinarides, despite their vast geographical separation (~600 km). The separation is best explained by the well‐dated tectonic displacement of the Tisza–Dacia microplate, which started in the Miocene (~16 Ma) and possibly carried part of the A. torrentium population to the current location of the Apuseni Mountains. This population may thus have been isolated from the Dinarides for a period of ca. 11 m.y. by marine and lacustrine phases of the Pannonian Basin. The inclusion of this geological event as a calibration point in divergence time analyses challenges currently accepted crayfish evolutionary time frames for the region, constraining the evolution of this area's crayfish to a much earlier date. We discuss why molecular clock calibrations previously employed to date European crayfish species divergences should therefore be reconsidered. 相似文献
78.
Multimode sensors as new tools for molecular recognition of testosterone,dihydrotestosterone and estradiol in children's saliva 下载免费PDF全文
Livia Alexandra Gugoasa Raluca‐Ioana Stefan‐van Staden Bogdan Calenic Juliette Legler 《Journal of molecular recognition : JMR》2015,28(1):10-19
Increased levels of testosterone (T2), dihydrotestosterone (DHT) and estradiol (E2) in children may be responsible for their early/delayed puberty and obesity conditions. Therefore, multimode sensors based on carbon matrices, such as graphite, graphene, fullerene C60 and multiwall carbon nanotubes modified with maltodextrin, were designed to assess reliably T2, DHT and E2 in children saliva. The modes used for the assay of hormones were stochastic mode (for qualitative and quantitative determination of hormones) and differential pulse voltammetry mode (for quantitative determination of hormones). The advantage of this type of sensors, for hormone analysis, is their possibility to reach low concentration levels— are placed for children saliva under the detection limit of standard methods (e.g. ELISA used for the determination of these hormones in saliva). This made the multimode sensors an excellent tool for clinical analysis and especially for determination of substances of clinical importance in saliva samples. The proposed method is fast and simple, and no sampling of saliva is required. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
79.
Cătană CS Cristea V Miron N Neagoe IB 《Roumanian archives of microbiology and immunology》2011,70(3):124-128
The importance of chronic inflammation in atherogenesis and cytokine involvement in all stages of atherosclerotic plaque development is now obvious. Our approach of the significant cytokines involved in atherogenesis or cardiovascular diseases is based on a correlation between clinical research and experiments on animal models. The contribution of IL-17 in atherogenesis remains controversial. In this study we investigated the role of IL-17 in cardiovascular diseases and in atherosclerosis associated with pathological aging. We performed a case-control study, enrolling subjects aged over 65 years in both groups. We included 40 patients with cardiovascular disorders and 10 healthy volunteers. IL-17 levels were measured in the serum of patients and healthy controls, along with serum total cholesterol and triglycerides. Significantly higher levels of IL-17 were obtained in patients compared to healthy controls (p<0.001). The level of this biomarker correlated significantly with two biochemical parameters - serum total cholesterol and triglycerides (the Pearson coefficient showed statistical significance, p=0.033, respectively p=0.043). We did not find any correlation between IL-17 and these two parameters in the control group. Our study is useful in understanding the physiopathological implications of IL-17 in the atherogenesis process. This could represent a starting point for future studies, including research regarding the therapeutic potential of IL-17 in pathological aging. 相似文献
80.
Mihai Bogdan Preda Ana‐Mihaela Lupan Carmen Alexandra Neculachi Livia Ioana Leti Ioana Madalina Fenyo Sinziana Popescu Evelyn Gabriela Rusu Catalina Iolanda Marinescu Maya Simionescu Alexandrina Burlacu 《Journal of cellular and molecular medicine》2020,24(18):10889-10897
Subcutaneous transplantation of mesenchymal stromal cells (MSC) emerged as an alternative to intravenous administration because it avoids the pulmonary embolism and prolongs post‐transplantation lifetime. The goal of this study was to investigate the mechanisms by which these cells could affect remote organs. To this aim, murine bone marrow–derived MSC were subcutaneously transplanted in different anatomical regions and the survival and behaviour have been followed. The results showed that upon subcutaneous transplantation in mice, MSC formed multicellular aggregates and did not migrate significantly from the site of injection. Our data suggest an important role of hypoxia‐inducible signalling pathways in stimulating local angiogenesis and the ensuing modulation of the kinetics of circulating cytokines with putative protective effects at distant sites. These data expand the current understanding of cell behaviour after subcutaneous transplantation and contribute to the development of a non‐invasive cell‐based therapy for distant organ protection. 相似文献