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71.
Lonneke Smeding Jan Willem Kuiper Frans B Pl?tz Martin CJ Kneyber AB Johan Groeneveld 《Respiratory research》2013,14(1):92
Background
Mechanical ventilation (MV) may cause ventilator-induced lung injury (VILI) and may thereby contribute to fatal multiple organ failure. We tested the hypothesis that injurious MV of lipopolysaccharide (LPS) pre-injured lungs induces myocardial inflammation and further dysfunction ex vivo, through calcium (Ca2+)-dependent mechanism.Materials and methods
N = 35 male anesthetized and paralyzed male Wistar rats were randomized to intratracheal instillation of 2 mg/kg LPS or nothing and subsequent MV with lung-protective settings (low tidal volume (Vt) of 6 mL/kg and 5 cmH2O positive end-expiratory pressure (PEEP)) or injurious ventilation (high Vt of 19 mL/kg and 1 cmH2O PEEP) for 4 hours. Myocardial function ex vivo was evaluated in a Langendorff setup and Ca2+ exposure. Key mediators were determined in lung and heart at the mRNA level.Results
Instillation of LPS and high Vt MV impaired gas exchange and, particularly when combined, increased pulmonary wet/dry ratio; heat shock protein (HSP)70 mRNA expression also increased by the interaction between LPS and high Vt MV. For the heart, C-X-C motif ligand (CXCL)1 and Toll-like receptor (TLR)2 mRNA expression increased, and ventricular (LV) systolic pressure, LV developed pressure, LV +dP/dtmax and contractile responses to increasing Ca2+ exposure ex vivo decreased by LPS. High Vt ventilation aggravated the effects of LPS on myocardial inflammation and dysfunction but not on Ca2+ responses.Conclusions
Injurious MV by high Vt aggravates the effects of intratracheal instillation of LPS on myocardial dysfunction, possibly through enhancing myocardial inflammation via pulmonary release of HSP70 stimulating cardiac TLR2, not involving Ca2+ handling and sensitivity. 相似文献72.
Background
Bacterial typing schemes based on the sequences of genes encoding surface antigens require databases that provide a uniform, curated, and widely accepted nomenclature of the variants identified. Due to the differences in typing schemes, imposed by the diversity of genes targeted, creating these databases has typically required the writing of one-off code to link the database to a web interface. Here we describe agdbNet, widely applicable web database software that facilitates simultaneous BLAST querying of multiple loci using either nucleotide or peptide sequences. 相似文献73.
74.
Hans-Christian Siebert Robert Kaptein Jaap J Beintema Ukun M Soedjanaatmadja Christine S Wright Ann Rice Reinhard G Kleineidam Susanne Kruse Roland Schauer Petra J.W Pouwels Johannis P Kamerling Hans-Joachim Gabius Johannes F.G Vliegenthart 《Glycoconjugate journal》1997,14(4):531-534
The side chains of tyrosine, tryptophan and histidine are able to produce CIDNP (Chemically Induced Dynamic Nuclear Polarization)
signals after laser irradiation in the presence of a suitable radical pair-generating dye. Elicitation of such a response
in proteins implies surface accessibility of the respective groups to the light-absorbing dye. In principle, this technique
allows the monitoring of the effect of ligand binding to a receptor and of site-directed mutagenesis on conformational aspects
of any protein if CIDNP-reactive amino acids are involved. The application of this method in glycosciences can provide insights
into the protein-carbohydrate interaction process, as illustrated in this initial model study for several N-acetyl-glucosamine-binding
lectins of increasing structural complexity as well as for a wild type bacterial sialidase and its mutants. Experimentally,
the shape and intensity of CIDNP signals are determined in the absence and in the presence of specific glycoligands. When
the carbohydrate is bound, CIDNP signals of side chain protons of tyrosine, tryptophan or histidine residues can be broadened
and of reduced intensity. This is the case for hevein, pseudo-hevein, the four hevein domains-containing lectin wheat germ
agglutinin (WGA) and the cloned B-domain of WGA 1 (domB) representing one hevein domain. This response indicates either a
spatial protection by the ligand or a ligand-induced positioning of formerly surface-exposed side chains into the protein’s
interior part, thereby precluding interaction with the photo-activated dye. Some signals of protons from the reactive side
chains can even disappear when the lectin-ligand complexes are monitored. The ligand binding, however, can apparently also
induce a conformational change in a related lectin that causes the appearance of a new signal, as seen for Urtica dioica agglutinin
(UDA) which consists of two hevein domains. Additionally, the three CIDNP-reactive amino acids are used as sensors for the
detection of conformational changes caused by pH variations or by deliberate amino acid exchanges, as determined for the isolectins
hevein and pseudo-hevein as well as for the cloned small sialidase of Clostridium perfringens and two of its mutants. Therefore,
CIDNP has proven to be an excellent tool for protein-carbohydrate binding studies and can be established in glycosciences
as a third biophysical method beside X-ray-crystallography and high-resolution multidimensional NMR studies which provides
reliable information of certain structural aspects of carbohydrate-binding proteins in solution.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
75.
Heuer H Solehati Q Zimmerling U Kleineidam K Schloter M Müller T Focks A Thiele-Bruhn S Smalla K 《Applied and environmental microbiology》2011,77(7):2527-2530
Two soils were amended three times with pig manure. The abundance of sulfonamide resistance genes was determined by quantitative PCR 2 months after each application. In both soils treated with sulfadiazine-containing manure, the numbers of copies of sul1 and sul2 significantly increased compared to numbers after treatments with antibiotic-free manure or a control and accumulated with repeated applications. 相似文献
76.
Salah Azzi Theo CJ Sas Yves Koudou Yves Le Bouc Jean-Claude Souberbielle Patricia Dargent-Molina Irène Netchine Marie-Aline Charles 《Epigenetics》2014,9(3):338-345
The ZAC1 gene, mapped to the 6q24 region, is part of a network of co-regulated imprinted genes involved in the control of embryonic growth. Loss of methylation at the ZAC1 differentially methylated region (DMR) is associated with transient neonatal diabetes mellitus, a developmental disorder involving growth retardation and diabetes in the first weeks of post-natal life. We assessed whether the degree of methylation of the ZAC1 DMR in leukocytes DNA extracted from cord blood is associated with fetal, birth and post-natal anthropometric measures or with C-peptide concentrations in cord serum. We also searched for an influence of dietary intake and maternal parameters on ZAC1 DMR methylation. We found positive correlations between the ZAC1 DMR methylation index (MI) and estimated fetal weight (EFW) at 32 weeks of gestation, weight at birth and weight at one year of age (respectively, r = 0.15, 0.09, 0.14; P values = 0.01, 0.15, 0.03). However, there were no significant correlations between the ZAC1 DMR MI and cord blood C-peptide levels. Maternal intakes of alcohol and of vitamins B2 were positively correlated with ZAC1 DMR methylation (respectively, r = 0.2 and 0.14; P = 0.004 and 0.04). The influence of ZAC1 seems to start in the second half of pregnancy and continue at least until the first year of life. The maternal environment also appears to contribute to the regulation of DNA methylation. 相似文献
77.
In the current model for Glc3Man9GlcNAc2-P-P-Dol assembly, Man5GlcNAc2-
P-P-Dol, Man-P-Dol, and Glc-P-Dol are synthesized on the cytoplasmic face
of the ER and diffuse transversely to the lumenal leaflet where the
synthesis of the lipid-bound precursor oligosaccharide is completed. To
establish the topological sites of Glc-P-Dol synthesis and the
lipid-mediated glucosyltransfer reactions involved in
Glc3Man9GlcNAc2-P-P-Dol synthesis in ER vesicles from pig brain, the
trypsin-sensitivity of Glc-P-Dol synthase activity and the Glc-P-
Dol:Glc0-2Man9GlcNAc2-P-P-Dol glucosyltransferases (GlcTases) was examined
in sealed microsomal vesicles. Since ER vesicles from brain do not contain
glucose 6-phosphate (Glc 6-P) phosphatase activity, the latency of the
lumenally oriented, processing glucosidase I/II activities was used to
assess the intactness of the vesicle preparations. Comparative enzymatic
studies with sealed ER vesicles from brain and kidney, a tissue that
contains Glc 6-P phosphatase, demonstrate the reliability of using the
processing glucosidase activities as latency markers for topological
studies with microsomal vesicles from non-gluconeogenic tissues lacking Glc
6-P phosphatase. The results obtained from the trypsin-sensitivity assays
with sealed microsomal vesicles from brain are consistent with a
topological model in which Glc-P-Dol is synthesized on the cytoplasmic face
of the ER, and subsequently utilized by the three Glc-P-Dol-mediated
GlcTases after "flip-flopping" to the lumenal monolayer.
相似文献
78.
79.
MH Bowie J Klimaszewski CJ Vink S Hodge SD Wratten 《New Zealand journal of zoology.》2013,40(4):268-284
Pitfall traps were used to monitor predatory arthropod numbers along two types of field boundary, a post and wire fence line and a Cupressus macrocarpa hedge, along the same paddock margin in Canterbury, New Zealand, over 24 months. The seven most abundant predator groups recorded were: Araneae > Phalangiidae > Staphylinidae > Coccinellidae > Chilopoda > Hemerobiidae > Carabidae. Araneae, Phalangiidae, Staphylinidae, Chilopoda and Hemerobiidae were found in larger numbers at the wire fence than at the hedge site, whereas the numbers of Carabidae and Coccinellidae adults exhibited no field margin preference. However, more species of Araneae and Staphylinidae were caught at the hedge site, whereas species richness of carabid beetles was greatest at the wire fence. Principal component analysis clearly separated the samples collected from the two habitats based on the assemblages of Araneae, Staphylinidae and Carabidae, and certain species in each of these taxonomic groups appeared to be particularly associated with one boundary type or the other. All the main taxonomic groups exhibited clear seasonal patterns, with distinct peaks in abundance occurring at certain times of the year. The results of the study reinforce the idea that management of field boundaries can be used to manipulate the type and abundance of particular groups of predatory arthropods, and that seasonal patterns should be taken into account in schemes of integrated pest management so that any adverse effects of biocide application on these beneficial species may be minimised. 相似文献
80.