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1.
This report describes a simple method for quantifying viable mycobacteria and for determining generation time. We used statistical models and computer analysis of growth curves generated for the slowly growing mycobacterium Mycobacterium paratuberculosis under controlled conditions to derive a mathematical formula relating the dependent variable, growth, to the independent variables, log10 number of organisms in the inoculum (inoculum size) and incubation time. Growth was measured by a radiometric method which detects 14CO2 release during metabolism of a 14C-labeled substrate. The radiometric method allowed for early detection of growth and detected as few as three viable bacteria. The coefficient of variation between culture vials inoculated with the same number of M. paratuberculosis was 0.083. Radiometric measurements were highly correlated to spectrophotometric and plate count methods for measuring growth (r = 0.962 and 0.992, respectively). The proportion of the total variability explained by the model in a goodness of fit test was 0.9994. Application of the model to broth cultures provided accurate estimates of the number of M. paratuberculosis (standard error = 0.21, log10 scale) and the growth rate (coefficient of variation, 0.03). Generation time was observed to be dependent upon the number of organisms in the inoculum. The model accurately described all phases of growth of M. paratuberculosis and can likely be applied to other slowly growing microorganisms. 相似文献
2.
Mesonephric adenocarcinoma is a rare primary neoplasm of the urinary bladder, composed of papillary and glandular structures with clear-cell features. A case is reported in which cytologic examination of urine specimens showed the distinctive dimorphic cell population of small cells in papillary formations and larger cells with features of a clear-cell adenocarcinoma, permitting a specific diagnosis. 相似文献
3.
Vincent Daien Isabelle Carriere Ryo Kawasaki Jean-Paul Cristol Max Villain Pierre Fesler Karen Ritchie Cecile Delcourt 《PloS one》2013,8(7)
Purpose
Retinal vascular caliber has been linked with increased cardiovascular risk and is predictive of cardiovascular pathology, including stroke and coronary heart disease. Oxidative stress, as well as inflammatory mechanisms, plays a major role in the pathogenesis and progression of atherosclerosis, plaque rupture and vascular thrombotic propensity. The purpose of this study is to explore the relationship between retinal vascular calibers and biomarkers of oxidative stress and inflammation, in subjects free of cardiovascular pathology.Patients and Methods
Cross-sectional analysis from a community-dwelling cohort comprising 1224 individuals aged 60 years and over, without a history of coronary or peripheral artery disease or stroke. Retinal vascular caliber was measured from fundus photographs using semi-automated standardized imaging software. Oxidative stress was evaluated using plasma superoxide dismutase 2 and glutathione peroxidase (GPx-3) activities, and inflammatory state was assessed using plasma high sensitivity C-reactive protein (hsCRP) and orosomucoid.Results
In a multivariate model controlling for cardiovascular risk factors, larger retinal arteriolar caliber was independently related to higher level of GPx-3 activity (p = 0.003) whereas larger venular caliber was associated with higher levels of hsCRP (p = 0.0001) and orosomucoid (p = 0.01).Conclusion
In the present study, biomarkers of oxidative stress regulation and inflammation were independently associated with retinal vascular calibers. This suggests that an assessment of retinal vessels may offer early and non-invasive detection of subclinical vascular pathology. 相似文献4.
Josiah MC Heyman 《The journal of the Royal Anthropological Institute》2000,6(4):635-652
High-scale morality is the study of moral ideas and sentiments deployed in relations that encompass multiple, geographically or socially distant populaces. The envisioning of distant people, their attributed moral personhood, the evaluation of their perceived behaviour, and the rectification of wrongs through the use of powerful organizations are key topics in high-scale morality. High-scale morality differs from existing anthropological approaches that emphasize local ethnography or contrastive moral ideas; it addresses the moralization of issues like world hunger, the drug trade, or international migration. The officers of the US Immigration and Naturalization Service understand and evaluate legal and illegal immigrants, as well as directly enacting moral rectification for the US polity. As they resolve moral dilemmas on their job, they utilize pervasive models for moral thought and action in capitalist, individualist, stratified, and bureaucratized societies. The article finishes by considering directions in which anthropology can contribute to understanding the moral dimension of global issues. 相似文献
5.
Patrick LJM Zeeuwen Jos Boekhorst Ellen H van den Bogaard Heleen D de Koning Peter MC van de Kerkhof Delphine M Saulnier Iris I van Swam Sacha AFT van Hijum Michiel Kleerebezem Joost Schalkwijk Harro M Timmerman 《Genome biology》2012,13(11):R101
Background
Recent advances in sequencing technologies have enabled metagenomic analyses of many human body sites. Several studies have catalogued the composition of bacterial communities of the surface of human skin, mostly under static conditions in healthy volunteers. Skin injury will disturb the cutaneous homeostasis of the host tissue and its commensal microbiota, but the dynamics of this process have not been studied before. Here we analyzed the microbiota of the surface layer and the deeper layers of the stratum corneum of normal skin, and we investigated the dynamics of recolonization of skin microbiota following skin barrier disruption by tape stripping as a model of superficial injury.Results
We observed gender differences in microbiota composition and showed that bacteria are not uniformly distributed in the stratum corneum. Phylogenetic distance analysis was employed to follow microbiota development during recolonization of injured skin. Surprisingly, the developing neo-microbiome at day 14 was more similar to that of the deeper stratum corneum layers than to the initial surface microbiome. In addition, we also observed variation in the host response towards superficial injury as assessed by the induction of antimicrobial protein expression in epidermal keratinocytes.Conclusions
We suggest that the microbiome of the deeper layers, rather than that of the superficial skin layer, may be regarded as the host indigenous microbiome. Characterization of the skin microbiome under dynamic conditions, and the ensuing response of the microbial community and host tissue, will shed further light on the complex interaction between resident bacteria and epidermis. 相似文献6.
Regulation of mTOR Complex 1 (mTORC1) by Raptor Ser863 and Multisite Phosphorylation 总被引:1,自引:0,他引:1
Kathryn G. Foster Hugo A. Acosta-Jaquez Yves Romeo Bilgen Ekim Ghada A. Soliman Audrey Carriere Philippe P. Roux Bryan A. Ballif Diane C. Fingar 《The Journal of biological chemistry》2010,285(1):80-94
The rapamycin-sensitive mTOR complex 1 (mTORC1) promotes protein synthesis, cell growth, and cell proliferation in response to growth factors and nutritional cues. To elucidate the poorly defined mechanisms underlying mTORC1 regulation, we have studied the phosphorylation of raptor, an mTOR-interacting partner. We have identified six raptor phosphorylation sites that lie in two centrally localized clusters (cluster 1, Ser696/Thr706 and cluster 2, Ser855/Ser859/Ser863/Ser877) using tandem mass spectrometry and generated phosphospecific antibodies for each of these sites. Here we focus primarily although not exclusively on raptor Ser863 phosphorylation. We report that insulin promotes mTORC1-associated phosphorylation of raptor Ser863 via the canonical PI3K/TSC/Rheb pathway in a rapamycin-sensitive manner. mTORC1 activation by other stimuli (e.g. amino acids, epidermal growth factor/MAPK signaling, and cellular energy) also promote raptor Ser863 phosphorylation. Rheb overexpression increases phosphorylation on raptor Ser863 as well as on the five other identified sites (e.g. Ser859, Ser855, Ser877, Ser696, and Thr706). Strikingly, raptor Ser863 phosphorylation is absolutely required for raptor Ser859 and Ser855 phosphorylation. These data suggest that mTORC1 activation leads to raptor multisite phosphorylation and that raptor Ser863 phosphorylation functions as a master biochemical switch that modulates hierarchical raptor phosphorylation (e.g. on Ser859 and Ser855). Importantly, mTORC1 containing phosphorylation site-defective raptor exhibits reduced in vitro kinase activity toward the substrate 4EBP1, with a multisite raptor 6A mutant more strongly defective that single-site raptor S863A. Taken together, these data suggest that complex raptor phosphorylation functions as a biochemical rheostat that modulates mTORC1 signaling in accordance with environmental cues. 相似文献
7.
By monitoring the thermally driven displacements of imbedded polystyrene microspheres via video fluorescence microscopy, we quantified the microstructural and micromechanical heterogeneities of wheat gliadin suspensions. We found that the degree of heterogeneity of the suspensions, as measured by the width and skewness of the microspheres' mean squared displacement (MSD) distribution, increased dramatically over a narrow range of gliadin concentrations. The ensemble-averaged MSD of a 250 mg/mL gliadin suspension exhibited a power-law behavior scaling linearly with time, a behavior similar to that observed for a homogeneous aqueous glycerol solution. However, the MSD distribution was wider and more asymmetric than for glycerol. With increasing concentration of gliadin, the ensemble-averaged MSD rapidly displayed a plateau at small time scales, the MSD distribution became wider and more asymmetric, and the local viscoelastic moduli extracted from multiple-particle-tracking measurements showed an increasingly wide range. 相似文献
8.
Aspects of the host specificity and pathogenicity of the hyphomycete, Verticillium lecanii , were investigated under laboratory conditions. DiVerences were observed in the pathogenicities of three strains of V. lecanii (DAOM 198499, DAOM 216596 and Vertalec) to the potato aphid Macrosiphum euphorbiae and Sphaerotheca fuliginea , the causal agent of cucumber powdery mildew. The estimated median lethal concentration required to achieve 50% mortality (LC ), 50 median lethal time leading to 50% mortality (LT ) and aphid net reproductive rate ( R ) 50 0 indicated that Vertalec and strain 198499 were more virulent to aphids than strain 216596. The estimated median colonization time for 50% of fungal colonies (CT ) showed that strain 50 198499 was the best antagonist of cucumber powdery mildew. Further comparison suggested that the mean pathogenicity of V. lecanii strain 198499 to cucumber powdery mildew was almost equivalent to that of Sporothrix flocculosa , a biological control agent of greenhouse fungal pathogens. These observations provide convincing experimental evidence that V. lecanii is biologically active against both arthropods and fungi. The potential of using V. lecanii strain 198499 in biological control is discussed. 相似文献
9.
van Beers JJ Raijmakers R Alexander LE Stammen-Vogelzangs J Lokate AM Heck AJ Schasfoort RB Pruijn GJ 《Arthritis research & therapy》2010,12(6):R219
Introduction
Rheumatoid arthritis (RA) frequently involves the loss of tolerance to citrullinated antigens, which may play a role in pathogenicity. Citrullinated fibrinogen is commonly found in inflamed synovial tissue and is a frequent target of autoantibodies in RA patients. To obtain insight into the B-cell response to citrullinated fibrinogen in RA, its autoepitopes were systematically mapped using a new methodology. 相似文献10.