42 research outputs found
Spontane bakterielle Keratitis in CD36-/- Knockout- MĂ€usen
PURPOSE. CD36 is a Class B scavenger receptor that is constitu- tively expressed in the corneal epithelium and has been impli- cated in many homeostatic functions, including the homeosta- sis of the epidermal barrier. The aim of this study is to determine (1) whether CD36 is required for the maintenance of the corneal epithelial barrier to infection, and (2) whether CD36-deficient mice present with an increased susceptibility to bacterial keratitis.
METHODS. The corneas of CD36- /- , TSP1- /- , TLR2- /- , and C57BL/6 WT mice were screened via slit lamp microscopy or ex vivo analysis. The epithelial tight junctions and mucin layer were assessed via LC-biotin and Rose Bengal staining, respec- tively. Bacterial quantification was performed on corneal but- tons and GFP-expressing Staphylococcus aureus was used to study bacterial binding.
RESULTS. CD36-/- mice develop spontaneous corneal defects that increased in frequency and severity with age. The mild corneal defects were characterized by a disruption in epithelial tight junctions and the mucin layer, an infiltrate of macro- phages, and increased bacterial binding. Bacterial quantifica- tion revealed high levels of Staphylococcus xylosus in the corneas of CD36-/- mice with severe defects, but not in wild-type controls.
CONCLUSIONS. CD36 -/- mice develop spontaneous bacterial keratitis independent of TLR2 and TSP1. The authors conclude that CD36 is a critical component of the corneal epithelial barrier, and in the absence of CD36 the barrier breaks down, allowing bacteria to bind to the corneal epithelium and result- ing in spontaneous keratitis. This is the first report of sponta- neous bacterial keratitis in mice. (Invest Ophthalmol Vis Sci. 2011;52:256â263) DOI:10.1167/iovs.10-556
Body Condition Scoring (BCS) zur Kontrolle von FĂŒtterungsfehlern bei MilchkĂŒhen im Biolandbau im Hinblick auf Risiken fĂŒr die Eutergesundheit
Body Condition Scoring (BCS) is a simple method to control the energy supply of single dairy cows as well as for the entire herd. This is very important especially for organic herds due to limited resources of energy intake. Within an udder health pro-gramme regular BCS using a 5 point scale with 0.25 pt. steps is a good tool to detect feeding problems. The impact of fattened cows during dry time and meagre cows during lactation peak on metabolic health and fertility is known, but not the correlation between BCS and udder health. Within the extension programme âpro-Qâ 530 dairy cows were scored at minimum twice during one lactation. The first time was 10 days before to 5 days after calving (BCS-1), the second time was in lactation up to day 100 (once or multiple investigation depending on visit frequency) using the lowest score during that time. Additionally the difference between these scores as a measurement for lipomobilization was calculated. These scores were compared to milk recording data (yield, protein, fat, urea) and the correlation to udder health (average logarithmic somatic cell count over the first 3 months after calving 100.000 ml âelevatedâ). The interrelationships between routinely milk records and udder health were poor. In contrast, first lactation cows showed a significant impact on udder health. âHealthyâ cows had an average BCS in dry time of 3.06 compared to 3.25 in âCC elevatedâ cows (p<0.05). Furthermore, the difference between both scores were -0.52 in âhealthyâ and -0.23 in âCC elevatedâ cows, respectively (p<0.01). There were no significant effects in elder cows. Results indicate that the control and balance of body condition can be an important issue in udder health management. Especially in heifers farmers should avoid fattening during late pregnancy period
Metagenome, metatranscriptome, and metaproteome approaches unraveled compositions and functional relationships of microbial communities residing in biogas plants
The production of biogas by anaerobic digestion (AD) of agricultural residues, organic wastes, animal excrements, municipal sludge, and energy crops has a firm place in sustainable energy production and bio-economy strategies. Focusing on the microbial community involved in biomass conversion offers the opportunity to control and engineer the biogas process with the objective to optimize its efficiency. Taxonomic profiling of biogas producing communities by means of high-throughput 16S rRNA gene amplicon sequencing provided high-resolution insights into bacterial and archaeal structures of AD assemblages and their linkages to fed substrates and process parameters. Commonly, the bacterial phyla Firmicutes and Bacteroidetes appeared to dominate biogas communities in varying abundances depending on the apparent process conditions. Regarding the community of methanogenic Archaea, their diversity was mainly affected by the nature and composition of the substrates, availability of nutrients and ammonium/ammonia contents, but not by the temperature. It also appeared that a high proportion of 16S rRNA sequences can only be classified on higher taxonomic ranks indicating that many community members and their participation in AD within functional networks are still unknown. Although cultivation-based approaches to isolate microorganisms from biogas fermentation samples yielded hundreds of novel species and strains, this approach intrinsically is limited to the cultivable fraction of the community. To obtain genome sequence information of non-cultivable biogas community members, metagenome sequencing including assembly and binning strategies was highly valuable. Corresponding research has led to the compilation of hundreds of metagenome-assembled genomes (MAGs) frequently representing novel taxa whose metabolism and lifestyle could be reconstructed based on nucleotide sequence information. In contrast to metagenome analyses revealing the genetic potential of microbial communities, metatranscriptome sequencing provided insights into the metabolically active community. Taking advantage of genome sequence information, transcriptional activities were evaluated considering the microorganismâs genetic background. Metaproteome studies uncovered enzyme profiles expressed by biogas community members. Enzymes involved in cellulose and hemicellulose decomposition and utilization of other complex biopolymers were identified. Future studies on biogas functional microbial networks will increasingly involve integrated multi-omics analyses evaluating metagenome, transcriptome, proteome, and metabolome datasets. © 2018, The Author(s)
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The Role of Petrimonas mucosa ING2-E5AT in Mesophilic Biogas Reactor Systems as Deduced from Multiomics Analyses
Members of the genera Proteiniphilum and Petrimonas were speculated to represent indicators reflecting process instability within anaerobic digestion (AD) microbiomes. Therefore, Petrimonas mucosa ING2-E5AT was isolated from a biogas reactor sample and sequenced on the PacBio RSII and Illumina MiSeq sequencers. Phylogenetic classification positioned the strain ING2-E5AT in close proximity to Fermentimonas and Proteiniphilum species (family Dysgonomonadaceae). ING2-E5AT encodes a number of genes for glycosyl-hydrolyses (GH) which are organized in Polysaccharide Utilization Loci (PUL) comprising tandem susCD-like genes for a TonB-dependent outer-membrane transporter and a cell surface glycan-binding protein. Different GHs encoded in PUL are involved in pectin degradation, reflecting a pronounced specialization of the ING2-E5AT PUL systems regarding the decomposition of this polysaccharide. Genes encoding enzymes participating in amino acids fermentation were also identified. Fragment recruitments with the ING2-E5AT genome as a template and publicly available metagenomes of AD microbiomes revealed that Petrimonas species are present in 146 out of 257 datasets supporting their importance in AD microbiomes. Metatranscriptome analyses of AD microbiomes uncovered active sugar and amino acid fermentation pathways for Petrimonas species. Likewise, screening of metaproteome datasets demonstrated expression of the Petrimonas PUL-specific component SusC providing further evidence that PUL play a central role for the lifestyle of Petrimonas species.Peer Reviewe
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The role of petrimonas mucosa ING2-E5at in mesophilic biogas reactor systems as deduced from multiomics analyses
Members of the genera Proteiniphilum and Petrimonas were speculated to represent indicators reflecting process instability within anaerobic digestion (AD) microbiomes. Therefore, Petrimonas mucosa ING2-E5AT was isolated from a biogas reactor sample and sequenced on the PacBio RSII and Illumina MiSeq sequencers. Phylogenetic classification positioned the strain ING2-E5AT in close proximity to Fermentimonas and Proteiniphilum species (family Dysgonomonadaceae). ING2-E5AT encodes a number of genes for glycosyl-hydrolyses (GH) which are organized in Polysaccharide Utilization Loci (PUL) comprising tandem susCD-like genes for a TonB-dependent outer-membrane transporter and a cell surface glycan-binding protein. Different GHs encoded in PUL are involved in pectin degradation, reflecting a pronounced specialization of the ING2-E5AT PUL systems regarding the decomposition of this polysaccharide. Genes encoding enzymes participating in amino acids fermentation were also identified. Fragment recruitments with the ING2-E5AT genome as a template and publicly available metagenomes of AD microbiomes revealed that Petrimonas species are present in 146 out of 257 datasets supporting their importance in AD microbiomes. Metatranscriptome analyses of AD microbiomes uncovered active sugar and amino acid fermentation pathways for Petrimonas species. Likewise, screening of metaproteome datasets demonstrated expression of the Petrimonas PUL-specific component SusC providing further evidence that PUL play a central role for the lifestyle of Petrimonas species. © 2020 by the authors. Licensee MDPI, Basel, Switzerland
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Spontaneous Bacterial Keratitis in CD36 Knockout Mice
Purpose: CD36 is a Class B scavenger receptor that is constitutively expressed in the corneal epithelium and has been implicated in many homeostatic functions, including the homeostasis of the epidermal barrier. The aim of this study is to determine (1) whether CD36 is required for the maintenance of the corneal epithelial barrier to infection, and (2) whether CD36-deficient mice present with an increased susceptibility to bacterial keratitis. Methods: The corneas of CD36â/â, TSP1â/â, TLR2â/â, and C57BL/6 WT mice were screened via slit lamp microscopy or ex vivo analysis. The epithelial tight junctions and mucin layer were assessed via LC-biotin and Rose Bengal staining, respectively. Bacterial quantification was performed on corneal buttons and GFP-expressing Staphylococcus aureus was used to study bacterial binding. Results: CD36â/â mice develop spontaneous corneal defects that increased in frequency and severity with age. The mild corneal defects were characterized by a disruption in epithelial tight junctions and the mucin layer, an infiltrate of macrophages, and increased bacterial binding. Bacterial quantification revealed high levels of Staphylococcus xylosus in the corneas of CD36â/â mice with severe defects, but not in wild-type controls. Conclusions: CD36â/â mice develop spontaneous bacterial keratitis independent of TLR2 and TSP1. The authors conclude that CD36 is a critical component of the corneal epithelial barrier, and in the absence of CD36 the barrier breaks down, allowing bacteria to bind to the corneal epithelium and resulting in spontaneous keratitis. This is the first report of spontaneous bacterial keratitis in mice
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Genomics and prevalence of bacterial and archaeal isolates from biogas-producing microbiomes
Background: To elucidate biogas microbial communities and processes, the application of high-throughput DNA analysis approaches is becoming increasingly important. Unfortunately, generated data can only partialy be interpreted rudimentary since databases lack reference sequences. Results: Novel cellulolytic, hydrolytic, and acidogenic/acetogenic Bacteria as well as methanogenic Archaea originating from different anaerobic digestion communities were analyzed on the genomic level to assess their role in biomass decomposition and biogas production. Some of the analyzed bacterial strains were recently described as new species and even genera, namely Herbinix hemicellulosilytica T3/55T, Herbinix luporum SD1DT, Clostridium bornimense M2/40T, Proteiniphilum saccharofermentans M3/6T, Fermentimonas caenicola ING2-E5BT, and Petrimonas mucosa ING2-E5AT. High-throughput genome sequencing of 22 anaerobic digestion isolates enabled functional genome interpretation, metabolic reconstruction, and prediction of microbial traits regarding their abilities to utilize complex bio-polymers and to perform specific fermentation pathways. To determine the prevalence of the isolates included in this study in different biogas systems, corresponding metagenome fragment mappings were done. Methanoculleus bourgensis was found to be abundant in three mesophilic biogas plants studied and slightly less abundant in a thermophilic biogas plant, whereas Defluviitoga tunisiensis was only prominent in the thermophilic system. Moreover, several of the analyzed species were clearly detectable in the mesophilic biogas plants, but appeared to be only moderately abundant. Among the species for which genome sequence information was publicly available prior to this study, only the species Amphibacillus xylanus, Clostridium clariflavum, and Lactobacillus acidophilus are of importance for the biogas microbiomes analyzed, but did not reach the level of abundance as determined for M. bourgensis and D. tunisiensis. Conclusions: Isolation of key anaerobic digestion microorganisms and their functional interpretation was achieved by application of elaborated cultivation techniques and subsequent genome analyses. New isolates and their genome information extend the repository covering anaerobic digestion community members. © 2017 The Author(s)
Intergroup contact and social change: Implications of negative and positive contact for collective action in advantaged and disadvantaged groups
Previous research has shown that (1) positive intergroup contact with an advantaged group can discourage collective action among disadvantaged-group members and (2) positive intergroup contact can encourage advantaged-group members to take action on behalf of disadvantaged outgroups. Two studies investigated the effects of negative as well as positive intergroup contact. Study 1 (N = 482) found that negative but not positive contact with heterosexual people was associated with sexual-minority studentsâ engagement in collective action (via group identification and perceived discrimination). Among heterosexual students, positive and negative contact were associated with, respectively, more and less LGB activism. Study 2 (N = 1,469) found that only negative contact (via perceived discrimination) predicted LGBT studentsâ collective action intentions longitudinally while only positive contact predicted heterosexual/cisgender studentsâ LGBT activism. Implications for the relationship between intergroup contact, collective action, and social change are discussed
The Added Value of Large-Eddy and Storm-Resolving Models for Simulating Clouds and Precipitation
More than one hundred days were simulated over very large domains with fine (0.156 km to 2.5 km) grid spacing for realistic conditions to test the hypothesis that storm (kilometer) and large-eddy (hectometer) resolving simulations would provide an improved representation of clouds and precipitation in atmospheric simulations. At scales that resolve convective storms (storm-resolving for short), the vertical velocity variance becomes resolved and a better physical basis is achieved for representing clouds and precipitation. Similarly to past studies we found an improved representation of precipitation at kilometer scales, as compared to models with parameterized convection. The main precipitation features (location, diurnal cycle and spatial propagation) are well captured already at kilometer scales, and refining resolution to hectometer scales does not substantially change the simulations in these respects. It does, however, lead to a reduction in the precipitation on the time-scales considered â most notably over the ocean in the tropics. Changes in the distribution of precipitation, with less frequent extremes are also found in simulations incorporating hectometer scales. Hectometer scales appear to be more important for the representation of clouds, and make it possible to capture many important aspects of the cloud field, from the vertical distribution of cloud cover, to the distribution of cloud sizes, and to the diel (daily) cycle. Qualitative improvements, particularly in the ability to differentiate cumulus from stratiform clouds, are seen when one reduces the grid spacing from kilometer to hectometer scales. At the hectometer scale new challenges arise, but the similarity of observed and simulated scales, and the more direct connection between the circulation and the unconstrained degrees of freedom make these challenges less daunting. This quality, combined with already improved simulation as compared to more parameterized models, underpins our conviction that the use and further development of storm-resolving models offers exciting opportunities for advancing understanding of climate and climate change
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Earth Virtualization Engines (EVE)
To manage Earth in the Anthropocene, new tools, new institutions, and new forms of international cooperation will be required. Earth Virtualization Engines is proposed as an international federation of centers of excellence to empower all people to respond to the immense and urgent challenges posed by climate change