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81.
Tiago Nunes Maria Josefina Etchevers Maria Jose Sandi Susana Pinó Donnay Teddy Grandjean Maria Pellisé Julián Panés Elena Ricart Juan Lucio Iovanna Jean-Charles Dagorn Mathias Chamaillard Miquel Sans 《PloS one》2014,9(1)
Background
The pancreatitis-associated protein (PAP) is increased in the serum of active inflammatory bowel disease (IBD) patients and its levels seem to be correlated with disease activity. Our aim was to evaluate the usefulness of serum and fecal PAP measurements to predict relapse in patients with inactive IBD.Materials and Methods
We undertook a 12-month prospective study that included 66 Crohn''s disease (CD) and 74 ulcerative colitis (UC) patients. At inclusion, patients were in clinical remission, defined by a Harvey-Bradshaw (HB) Index≤4 (CD) or a partial Mayo Score (MS)<3 (UC), along with a normal serum C reactive protein (CRP) and fecal calprotectin. Patients were followed every 3 months. Blood and stool samples were collected and a clinical evaluation was performed at each visit. Serum PAP and CRP levels as well as fecal concentrations of PAP and calprotectin were assessed.Results
Active CD patients had an increased mean serum PAP at the diagnosis of the flare (104.1 ng/ml) and 3 months prior to activity (22.68 ng/ml) compared with patients in remission (13.26 ng/ml), p<0.05. No significant change in serum PAP levels in UC and fecal PAP levels in CD and UC were detected during disease activity. In CD, serum PAP was a poor diagnostic predictor of disease activity, with an AUC of 0.69. In patients in remission, fecal PAP was barely detectable in UC compared with CD patients.Conclusion
Serum PAP is increased only in active CD patients, but this marker does not predict disease activity. Inactive UC patients have marked low levels of PAP in fecal samples compared with CD patients. 相似文献82.
Intestinal microbiota composition in fishes is influenced by host ecology and environment 总被引:2,自引:0,他引:2
The digestive tracts of vertebrates are colonized by complex assemblages of micro-organisms, collectively called the gut microbiota. Recent studies have revealed important contributions of gut microbiota to vertebrate health and disease, stimulating intense interest in understanding how gut microbial communities are assembled and how they impact host fitness (Sekirov et al. 2010). Although all vertebrates harbour a gut microbiota, current information on microbiota composition and function has been derived primarily from mammals. Comparisons of different mammalian species have revealed intriguing associations between gut microbiota composition and host diet, anatomy and phylogeny (Ley et al. 2008b). However, mammals constitute <10% of all vertebrate species, and it remains unclear whether similar associations exist in more diverse and ancient vertebrate lineages such as fish. In this issue, Sullam et al. (2012) make an important contribution toward identifying factors determining gut microbiota composition in fishes. The authors conducted a detailed meta-analysis of 25 bacterial 16S rRNA gene sequence libraries derived from the intestines of different fish species. To provide a broader context for their analysis, they compared these data sets to a large collection of 16S rRNA gene sequence data sets from diverse free-living and host-associated bacterial communities. Their results suggest that variation in gut microbiota composition in fishes is strongly correlated with species habitat salinity, trophic level and possibly taxonomy. Comparison of data sets from fish intestines and other environments revealed that fish gut microbiota compositions are often similar to those of other animals and contain relatively few free-living environmental bacteria. These results suggest that the gut microbiota composition of fishes is not a simple reflection of the micro-organisms in their local habitat but may result from host-specific selective pressures within the gut (Bevins & Salzman 2011). 相似文献
83.
Adar SD Klein R Klein BE Szpiro AA Cotch MF Wong TY O'Neill MS Shrager S Barr RG Siscovick DS Daviglus ML Sampson PD Kaufman JD 《PLoS medicine》2010,7(11):e1000372
Background
Long- and short-term exposures to air pollution, especially fine particulate matter (PM2.5), have been linked to cardiovascular morbidity and mortality. One hypothesized mechanism for these associations involves microvascular effects. Retinal photography provides a novel, in vivo approach to examine the association of air pollution with changes in the human microvasculature.Methods and Findings
Chronic and acute associations between residential air pollution concentrations and retinal vessel diameters, expressed as central retinal arteriolar equivalents (CRAE) and central retinal venular equivalents (CRVE), were examined using digital retinal images taken in Multi-Ethnic Study of Atherosclerosis (MESA) participants between 2002 and 2003. Study participants (46 to 87 years of age) were without clinical cardiovascular disease at the baseline examination (2000–2002). Long-term outdoor concentrations of PM2.5 were estimated at each participant''s home for the 2 years preceding the clinical exam using a spatio-temporal model. Short-term concentrations were assigned using outdoor measurements on the day preceding the clinical exam. Residential proximity to roadways was also used as an indicator of long-term traffic exposures. All associations were examined using linear regression models adjusted for subject-specific age, sex, race/ethnicity, education, income, smoking status, alcohol use, physical activity, body mass index, family history of cardiovascular disease, diabetes status, serum cholesterol, glucose, blood pressure, emphysema, C-reactive protein, medication use, and fellow vessel diameter. Short-term associations were further controlled for weather and seasonality. Among the 4,607 participants with complete data, CRAE were found to be narrower among persons residing in regions with increased long- and short-term levels of PM2.5. These relationships were observed in a joint exposure model with −0.8 µm (95% confidence interval [CI] −1.1 to −0.5) and −0.4 µm (95% CI −0.8 to 0.1) decreases in CRAE per interquartile increases in long- (3 µg/m3) and short-term (9 µg/m3) PM2.5 levels, respectively. These reductions in CRAE are equivalent to 7- and 3-year increases in age in the same cohort. Similarly, living near a major road was also associated with a −0.7 µm decrease (95% CI −1.4 to 0.1) in CRAE. Although the chronic association with CRAE was largely influenced by differences in exposure between cities, this relationship was generally robust to control for city-level covariates and no significant differences were observed between cities. Wider CRVE were associated with living in areas of higher PM2.5 concentrations, but these findings were less robust and not supported by the presence of consistent acute associations with PM2.5.Conclusions
Residing in regions with higher air pollution concentrations and experiencing daily increases in air pollution were each associated with narrower retinal arteriolar diameters in older individuals. These findings support the hypothesis that important vascular phenomena are associated with small increases in short-term or long-term air pollution exposures, even at current exposure levels, and further corroborate reported associations between air pollution and the development and exacerbation of clinical cardiovascular disease. Please see later in the article for the Editors'' Summary 相似文献84.
Krupka M Raska M Belakova J Horynova M Novotny R Weigl E 《Biomedical papers of the Medical Faculty of the University Palacky, Olomouc, Czechoslovakia》2007,151(2):175-186
Background: Borrelia burgdorferi sensu lato is a group of at least twelve closely related species some of which are responsible for Lyme disease, the most frequent zoonosis in Europe and the USA. Many of the biological features of Borrelia are unique in prokaryotes and very interesting not only from the medical viewpoint but also from the view of molecular biology. Methods: Relevant recent articles were searched using PubMed and Google search tools. Results and Conclusion: This is a review of the biological, genetic and physiological features of the spirochete species group, Borrelia burgdorferi sensu lato. In spite of a lot of recent articles focused on B. burgdorferi sensu lato, many features of Borrelia biology remain obscure. It is one of the main reasons for persisting problems with prevention, diagnosis and therapy of Lyme disease. The aim of the review is to summarize ongoing current knowledge into a lucid and comprehensible form. 相似文献
85.
Vasiliskov V. A. Shershov V. E. Miftahov R. A. Kuznetsova V. E. Radko S. P. Lisitsa A. V. Lapa S. A. Surzhikov S. A. Timofeev E. N. Zasedatelev A. S. Chudinov A. V. 《Russian Journal of Bioorganic Chemistry》2020,46(3):312-314
Russian Journal of Bioorganic Chemistry - An effect of primer strand slippage was observed in the primer extension reaction due to replacement of thymidine triphosphate for modified analogs of... 相似文献
86.
Lapa S. A. Shershov V. E. Krasnov G. S. Volkova O. S. Kuznetsova V. E. Radko S. P. Zasedatelev A. S. Chudinov A. V. 《Russian Journal of Bioorganic Chemistry》2020,46(4):551-556
Russian Journal of Bioorganic Chemistry - A method of thermal dissociation of DNA–protein conjugates was developed for the selection of aptamers to human alpha-fetoprotein. The method is... 相似文献
87.
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89.
Savanna chimpanzees are useful as referential models for early hominins, and here potential differences between chimpanzee and early hominin ecology is the focus. Whereas chimpanzees inhabit only a handful of modern African savannas, there is evidence that early hominins occupied relatively more open and arid savannas than those in which chimpanzees live. In order to help expand potential models of early hominin palaeoecology beyond savanna chimpanzee-like scenarios, and to provide a basis for future modeling and testing of actual hominin diets, this study compares the types of plant foods available in modern semi-arid savannas of northern Tanzania to plant foods at savanna chimpanzee sites. The semi-arid savannas are not occupied by modern chimpanzees, but are potentially similar to environments occupied by some early hominins. Compared to savanna chimpanzee habitats, the northern Tanzania semi-arid savanna has a lower density and fewer species of trees that produce fleshy fruits. Additionally, the most abundant potential hominin plant foods are seasonally available Acacia seeds/pods and flowers, grass seeds, and the underground parts of marsh plants, as evidenced by vegetation surveys and by studies of the diets of baboons that forage in similar areas. The information from this study should be useful for framing hypotheses about hominin diets for sites with palaeoenvironmental contexts similar to those of the northern Tanzania semi-arid savannas and for contextualising tests of actual hominin diets (e.g., those based on dental microwear or isotopes). 相似文献
90.
Influence of specific fermentation conditions on natural microflora of pomace in “Grappa” production
L Iacumin M Manzano F Cecchini S Orlic R Zironi G Comi 《World journal of microbiology & biotechnology》2012,28(4):1747-1759
As reported in the European Community regulation, grappa is a spirit beverage made in Italy from marc that has been steam
distilled or distilled after the addition of water. Grape marc from red grapes has already undergone alcoholic fermentation
with the must and can be distilled immediately. Grape marc from white grapes does not contain ethanol but contains sugars
that are fermented by spontaneous anaerobic fermentation during a storage period. The characteristic aroma of grappa consists
of a large number of volatile compounds, which arise from various sources, the most important of which is yeast. Very few
studies have been undertaken to characterize the natural populations of yeast during the fermentation of grape marc. The goal
of this study was to understand how different pHs, temperatures and yeast starter cultures affect the growth and dynamics
of yeast species involved in pomace fermentation, which could be the basis for improving the final quality of grappa production.
We found that a temperature of 15°C has the greatest effect on improving the quality of the product. Unfortunately, due to
the solid state of the grape marc and the impossibility of its mixing, it appears that acidification and the addition of yeast
starter cultures during the silage period are not effective. 相似文献