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111.
Wilbur Y. W. Lew Evelyn Bayna Erminia Dalle Molle Riccardo Contu Gianluigi Condorelli Tong Tang 《PloS one》2014,9(9)
Background
Exposure to subclinical levels of lipopolysaccharide (LPS) occurs commonly and is seemingly well tolerated. However, recurrent LPS exposure induces cardiac fibrosis over 2 to 3 months in a murine model, not mediated by the renin-angiotensin system. Subclinical LPS induces cardiac fibrosis by unique mechanisms.Methods
In C57/Bl6 mice, LPS (10 mg/kg) or saline (control) were injected intraperitoneally once a week for 1–4 weeks. Mice showed no signs of distress, change in activity, appetite, or weight loss. Mice were euthanized after 3 days, 1, 2, or 4 weeks to measure cardiac expression of fibrosis-related genes and potential mediators (measured by QRT-PCR), including micro-RNA (miR) and NADPH oxidase (NOX). Collagen fraction area of the left ventricle was measured with picrosirius red staining. Cardiac fibroblasts isolated from adult mouse hearts were incubated with 0, 0.1, 1.0 or 10 ng/ml LPS for 48 hours.Results
Cardiac miR expression profiling demonstrated decreased miR-29c after 3 and 7 days following LPS, which were confirmed by QRT-PCR. The earliest changes in fibrosis-related genes and mediators that occurred 3 days after LPS were increased cardiac expression of TIMP-1 and NOX-2 (but not of NOX-4). This persisted at 1 and 2 weeks, with additional increases in collagen Iα1, collagen IIIα1, MMP2, MMP9, TIMP1, TIMP2, and periostin. There was no change in TGF-β or connective tissue growth factor. Collagen fraction area of the left ventricle increased after 2 and 4 weeks of LPS. LPS decreased miR-29c and increased NOX-2 in isolated cardiac fibroblasts.Conclusions
Recurrent exposure to subclinical LPS induces cardiac fibrosis after 2–4 weeks. Early changes 3 days after LPS were decreased miR-29c and increased NOX2 and TIMP1, which persisted at 1 and 2 weeks, along with widespread activation of fibrosis-related genes. Decreased miR-29c and increased NOX2, which induce cardiac fibrosis in other conditions, may uniquely mediate LPS-induced cardiac fibrosis. 相似文献112.
In beekeeping, queen honey bees are often temporarily kept alive in cages. We determined the survival of newly-emerged virgin honey bee queens every day for seven days in an experiment that simultaneously investigated three factors: queen cage type (wooden three-hole or plastic), attendant workers (present or absent) and food type (sugar candy, honey, or both). Ten queens were tested in each of the 12 combinations. Queens were reared using standard beekeeping methods (Doolittle/grafting) and emerged from their cells into vials held in an incubator at 34C. All 12 combinations gave high survival (90 or 100%) for three days but only one method (wooden cage, with attendants, honey) gave 100% survival to day seven. Factors affecting queen survival were analysed. Across all combinations, attendant bees significantly increased survival (18% vs. 53%, p<0.001). In addition, there was an interaction between food type and cage type (p<0.001) with the honey and plastic cage combination giving reduced survival. An additional group of queens was reared and held for seven days using the best method, and then directly introduced using smoke into queenless nucleus colonies that had been dequeened five days previously. Acceptance was high (80%, 8/10) showing that this combination is also suitable for preparing queens for introduction into colonies. Having a simple method for keeping newly-emerged virgin queens alive in cages for one week and acceptable for introduction into queenless colonies will be useful in honey bee breeding. In particular, it facilitates the screening of many queens for genetic or phenotypic characteristics when only a small proportion meets the desired criteria. These can then be introduced into queenless hives for natural mating or insemination, both of which take place when queens are one week old. 相似文献
113.
Martino Orrù Efisio Mattana Hugh W. Pritchard Gianluigi Bacchetta 《Annals of botany》2012,110(8):1651-1660
Background and Aims
The importance of thermal thresholds for predicting seed dormancy release and germination timing under the present climate conditions and simulated climate change scenarios was investigated. In particular, Vitis vinifera subsp. sylvestris was investigated in four Sardinian populations over the full altitudinal range of the species (from approx. 100 to 800 m a.s.l).Methods
Dried and fresh seeds from each population were incubated in the light at a range of temperatures (10–25 and 25/10 °C), without any pre-treatment and after a warm (3 months at 25 °C) or a cold (3 months at 5 °C) stratification. A thermal time approach was then applied to the germination results for dried seeds and the seed responses were modelled according to the present climate conditions and two simulated scenarios of the Intergovernmental Panel on Climate Change (IPCC): B1 (+1·8 °C) and A2 (+3·4 °C).Key Results
Cold stratification released physiological dormancy, while very few seeds germinated without treatments or after warm stratification. Fresh, cold-stratified seeds germinated significantly better (>80 %) at temperatures ≥20 °C than at lower temperatures. A base temperature for germination (Tb) of 9·0–11·3 °C and a thermal time requirement for 50 % of germination (θ50) ranging from 33·6 °Cd to 68·6 °Cd were identified for non-dormant cold-stratified seeds, depending on the populations. This complex combination of thermal requirements for dormancy release and germination allowed prediction of field emergence from March to May under the present climatic conditions for the investigated populations.Conclusions
The thermal thresholds for seed germination identified in this study (Tb and θ50) explained the differences in seed germination detected among populations. Under the two simulated IPCC scenarios, an altitude-related risk from climate warming is identified, with lowland populations being more threatened due to a compromised seed dormancy release and a narrowed seed germination window. 相似文献114.
In this paper, we analyzed the ground and excited states of phospholamban (PLN), a membrane protein that regulates sarcoplasmic reticulum calcium ATPase (SERCA), in different membrane mimetic environments. Previously, we proposed that the conformational equilibria of PLN are central to SERCA regulation. Here, we show that these equilibria detected in micelles and bicelles are also present in native sarcoplasmic reticulum lipid membranes as probed by MAS solid-state NMR. Importantly, we found that the kinetics of conformational exchange and the extent of ground and excited states in detergent micelles and lipid bilayers are different, revealing a possible role of the membrane composition on the allosteric regulation of SERCA. Since the extent of excited states is directly correlated to SERCA inhibition, these findings open up the exciting possibility that calcium transport in the heart can be controlled by the lipid bilayer composition. This article is part of a Special Issue entitled: Membrane protein structure and function. 相似文献
115.
Baldassarre F Vergaro V Scarlino F De Santis F Lucarelli G Torre AD Ciccarella G Rinaldi R Giannelli G Leporatti S 《Macromolecular bioscience》2012,12(5):656-665
The efficient internalization of TGF-beta inhibitor-loaded polyelectrolyte capsules and particles is studied in two HCC cell lines. Two polyelectrolyte pairs (biocompatible but not degradable and biodegradable crosslinked with gluteraldehyde) are employed for coating. The capsules are characterized by SEM. LY is successfully loaded inside the core and embedded between polymer layers. MS is used to quantify the loading efficiency by comparing post-loading and core-loading methods, since both coated templates and hollow shells are used as carriers. CLSM confirms dissolution of the pre-formed multilayer upon enzymatic degradation as the method of release, and migration assays demonstrate a higher inhibition efficiency of TGF-beta in tailored biodegradable capsules compared to free LY administration. 相似文献
116.
Seed germination (effects of light, temperature, NaCl and KNO3) of the coastal endangered species Crucianella maritima was investigated by testing seeds from three different populations. Data were analyzed by means of Generalized Linear Mixed Model (GLMM). The principal results showed that germination of C. maritima seeds was characterized by photoinhibition, absence of primary dormancy and salt-induced secondary dormancy, with no need for high nutrient availability (KNO3). Intraspecific differences in germination pattern emerged, apparently due to a different seed mass. These results show important germination traits of C. maritima which should be taken into account in possible reintroduction attempts aimed at restoring threatened populations of this species. 相似文献
117.
Background: A quantifiable and reliable technique for the determination of body circadian phase applicable to non-laboratory studies would allow the evaluation of circadian dysregulation. In this study we evaluated feasible methodologies to individualize whole body circadian phase in lung cancer patients. Methods: Cortisol and melatonin serum levels were measured in blood samples collected every 4 h for 24 h from eleven male controls and nine men suffering from non-small cell lung cancer. Circadian rhythmicity was evaluated and the 4-hourly fractional variations (FV) were calculated to evaluate the dynamics of the rise and fall in serum levels. Results: Overall cortisol serum levels were higher in cancer patients (p < 0.001), and lower for melatonin, but not significantly (p = 0.261). Original serum levels of cortisol and melatonin each showed a prominent 24 h oscillation in both study groups, with highest values at night for melatonin and near awakening for cortisol. Using all data after normalization to percent of individual mean, ANOVA detected a significant time-effect (p < 0.001) and cosinor analysis detected a significant 24 h rhythm (p < 0.001) in each group. Overall fractional variation (FV) levels were lower for cortisol in cancer patients and higher for melatonin, but these differences were not significant. FV levels of cortisol and melatonin each showed a prominent 24 h oscillation in both study groups, with highest values prior to darkness onset for melatonin and near mid-dark for cortisol. ANOVA also detected a significant time-effect (p < 0.002) and cosinor analysis detected a significant 24 h rhythm (p < 0.001) for FV in each group, with maximal FV preceding maximal serum levels by ~3 h for melatonin and ~5 h for cortisol. Conclusions: A chronobiological evaluation of serum levels and fractional variations for cortisol and especially melatonin is a valuable methodology to define body circadian phase in lung cancer patients. It is possible to describe the complex process of hormone secretion with a methodology that allows the definition of both temporal characteristics and dynamic components. Impact: This kind of analysis might be useful in the study of hormone secretion(s) in cancer patients and other diseases and to guide therapeutic interventions. While lung cancer patients may have a negative prognostic value based upon stage and/or other hormonal aspects of their hypothalamus–pituitary–thyroid–adrenal axis function, patients that nevertheless maintain circadian rhythmicity in key body rhythm markers may still be eligible candidates for a chronotherapeutic approach of treatment(s). 相似文献
118.
Bigini P Diana V Barbera S Fumagalli E Micotti E Sitia L Paladini A Bisighini C De Grada L Coloca L Colombo L Manca P Bossolasco P Malvestiti F Fiordaliso F Forloni G Morbidelli M Salmona M Giardino D Mennini T Moscatelli D Silani V Cova L 《PloS one》2012,7(2):e32326
Stem Cell (SC) therapy is one of the most promising approaches for the treatment of Amyotrophic Lateral Sclerosis (ALS). Here we employed Super Paramagnetic Iron Oxide nanoparticles (SPIOn) and Hoechst 33258 to track human Amniotic Fluid Cells (hAFCs) after transplantation in the lateral ventricles of wobbler (a murine model of ALS) and healthy mice. By in vitro, in vivo and ex vivo approaches we found that: 1) the main physical parameters of SPIOn were maintained over time; 2) hAFCs efficiently internalized SPIOn into the cytoplasm while Hoechst 33258 labeled nuclei; 3) SPIOn internalization did not alter survival, cell cycle, proliferation, metabolism and phenotype of hAFCs; 4) after transplantation hAFCs rapidly spread to the whole ventricular system, but did not migrate into the brain parenchyma; 5) hAFCs survived for a long time in the ventricles of both wobbler and healthy mice; 6) the transplantation of double-labeled hAFCs did not influence mice survival. 相似文献
119.
Buffy JJ Buck-Koehntop BA Porcelli F Traaseth NJ Thomas DD Veglia G 《Journal of molecular biology》2006,358(2):420-429
Sarcolipin (SLN) is an integral membrane protein that is expressed in both skeletal and cardiac muscle, where it inhibits SERCA (calcium ATPase) by lowering its apparent Ca2+ affinity in a manner similar to that of its homologue phospholamban (PLN). We use solution NMR to map the structural changes occurring within SLN upon interaction with the regulatory target, SERCA, co-reconstituting the two proteins in dodecylphosphocholine (DPC) detergent micelles, a system that preserves the native structure of SLN and the activity of SERCA, with the goal of comparing these interactions with those of the previously studied PLN-SERCA complex. Our analysis of the structural dynamics of SLN in DPC micelles shows this polypeptide to be partitioned into four subdomains: a short unstructured N terminus (residues 1-6), a short dynamic helix (residues 7-14), a more rigid helix (residues 15-26), and an unstructured C terminus (residues 27-31). Upon addition of SERCA, the different domains behave according to their dynamics, molding onto the surface of the enzyme. Remarkably, each domain of SLN behaves in a manner similar to that of the corresponding domains in PLN, supporting the hypothesis that both SLN and PLN bind SERCA in the same groove and with similar mechanisms. 相似文献
120.
Salti R Tarquini R Stagi S Perfetto F Cornélissen G Laffi G Mazzoccoli G Halberg F 《Neuro endocrinology letters》2006,27(1-2):73-80
OBJECTIVES: Changes in magnetic field are associated with a decrease in nocturnal urinary melatonin excretion. Television screens emit low and very low frequency electromagnetic waves (radiofrequencies and light) and exposure to them may be associated with a decrease in 24-hour melatonin in children's urine. Design and setting. An observational study in schools of Cavriglia, Italy, determined melatonin in 24-hour urines from 42 boys and 32 girls 6 to 13 years of age after one week of watching TV and after another week of abstaining from watching TV. RESULTS AND MAIN FINDINGS: In a gender- and age-dependent fashion, exposure to a television screen was associated with lower urinary melatonin concentrations, affecting particularly younger children at a pubertal stage when important changes in melatonin's time structure occur. CONCLUSION: Additional work should test further relations to growth, maturation and development, focusing on any adverse effect from exposure to a television screen also on obesity from a neuro-hormonal viewpoint, quite apart from any decreased activity and/or other lifestyle alterations associated with watching TV. 相似文献