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991.
Francesca Bottacini Christian Milani Francesca Turroni Borja Sánchez Elena Foroni Sabrina Duranti Fausta Serafini Alice Viappiani Francesco Strati Alberto Ferrarini Massimo Delledonne Bernard Henrissat Pedro Coutinho Gerald F. Fitzgerald Abelardo Margolles Douwe van Sinderen Marco Ventura 《PloS one》2012,7(9)
Bifidobacteria are known as anaerobic/microaerophilic and fermentative microorganisms, which commonly inhabit the gastrointestinal tract of various animals and insects. Analysis of the 2,167,301 bp genome of Bifidobacterium asteroides PRL2011, a strain isolated from the hindgut of Apis mellifera var. ligustica, commonly known as the honey bee, revealed its predicted capability for respiratory metabolism. Conservation of the latter gene clusters in various B. asteroides strains enforces the notion that respiration is a common metabolic feature of this ancient bifidobacterial species, which has been lost in currently known mammal-derived Bifidobacterium species. In fact, phylogenomic based analyses suggested an ancient origin of B. asteroides and indicates it as an ancestor of the genus Bifidobacterium. Furthermore, the B. asteroides PRL2011 genome encodes various enzymes for coping with toxic products that arise as a result of oxygen-mediated respiration. 相似文献
992.
G Llauradó JM González-Clemente E Maymó-Masip D Subías J Vendrell MR Chacón 《PloS one》2012,7(8):e43919
Objective
To test the usefulness of serum concentrations of tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) and soluble scavenger receptor CD163 (sCD163) as markers of subtle inflammation in patients with type 1 diabetes mellitus (T1DM) without clinical cardiovascular (CV) disease and to evaluate their relationship with arterial stiffness (AS).Methods
Sixty-eight patients with T1DM and 68 age and sex-matched, healthy subjects were evaluated. Anthropometrical variables and CV risk factors were recorded. Serum concentrations of sTWEAK and sCD163 were measured. AS was assessed by aortic pulse wave velocity (aPWV). All statistical analyses were stratified by gender.Results
T1DM patients showed lower serum concentrations of sTWEAK (Men: 1636.5 (1146.3–3754.8) pg/mL vs. 765.9 (650.4–1097.1) pg/mL; p<0.001. Women: 1401.0 (788.0–2422.2) pg/mL vs. 830.1 (562.6–1175.9) pg/mL; p = 0.011) compared with their respective controls. Additionally, T1DM men had higher serum concentrations of sCD163 (285.0 (247.7–357.1) ng/mL vs. 224.8 (193.3–296.5) ng/mL; p = 0.012) compared with their respective controls. sTWEAK correlated negatively with aPWV in men (r = −0.443; p<0.001). However, this association disappeared after adjusting for potential confounders. In men, the best multiple linear regression model showed that the independent predictors of sTWEAK were T1DM and WHR (R2 = 0.640; p<0.001). In women, T1DM and SBP were the independent predictors for sTWEAK (R2 = 0.231; p = 0.001).Conclusion
sTWEAK is decreased in T1DM patients compared with age and sex-matched healthy subjects after adjusting for classic CV risk factors, although sTWEAK levels may be partially influenced by some of them. Additionally, T1DM men have higher serum concentrations of sCD163. These results point out an association between the inflammatory system and CV risk in T1DM. 相似文献993.
Saliva proteomics as an emerging, non-invasive tool to study livestock physiology, nutrition and diseases 总被引:1,自引:0,他引:1
Saliva is an extraordinary fluid in terms of research and diagnostic possibilities. Its composition in electrolytes, hormones and especially its proteome contains information about feeding status, nutritional requirements and adaptations to diet and environment, and also about health status of animals. It is easy to collect on a non-invasive and routine basis without any need for special training. Therefore, the analysis of salivary proteomes is going to emerge into a field of high interest with the future goal to maintain and improve livestock productivity and welfare. Moreover, the comprehensive analysis and identification of salivary proteins and peptides in whole and glandular saliva is a necessary pre-requisite to identify animal disease biomarkers and a powerful tool to better understand animal physiology. This review focuses on the different approaches used to study the salivary proteomes of farm animals, in respect to the physiology of nutrition and food perception in relation to food choices. The potential of animal saliva as a source of disease biomarkers will also be pointed out. Special emphasis is laid on the 'ruminating triad' - cattle, goat and sheep - as well as swine as major species of animal production in Western and Southern Europe. 相似文献
994.
Rodrigues SP Ventura JA Aguilar C Nakayasu ES Choi H Sobreira TJ Nohara LL Wermelinger LS Almeida IC Zingali RB Fernandes PM 《Journal of Proteomics》2012,75(11):3191-3198
Papaya meleira virus (PMeV) is so far the only described laticifer-infecting virus, the causal agent of papaya (Carica papaya L.) sticky disease. The effects of PMeV on the laticifers' regulatory network were addressed here through the proteomic analysis of papaya latex. Using both 1-DE- and 1D-LC-ESI-MS/MS, 160 unique papaya latex proteins were identified, representing 122 new proteins in the latex of this plant. Quantitative analysis by normalized spectral counting revealed 10 down-regulated proteins in the latex of diseased plants, 9 cysteine proteases (chymopapain) and 1 latex serine proteinase inhibitor. A repression of papaya latex proteolytic activity during PMeV infection was hypothesized. This was further confirmed by enzymatic assays that showed a reduction of cysteine-protease-associated proteolytic activity in the diseased papaya latex. These findings are discussed in the context of plant responses against pathogens and may greatly contribute to understand the roles of laticifers in plant stress responses. 相似文献
995.
Hasson RE Adam TC Davis JN Kelly LA Ventura EE Byrd-Williams CE Toledo-Corral CM Roberts CK Lane CJ Azen SP Chou CP Spruijt-Metz D Weigensberg MJ Berhane K Goran MI 《Obesity (Silver Spring, Md.)》2012,20(4):811-818
The purpose of this study was to examine ethnic differences in the metabolic responses to a 16-week intervention designed to improve insulin sensitivity (SI), adiposity, and inflammation in obese African-American and Latino adolescents. A total of 100 participants (African Americans: n = 48, Latino: n = 52; age: 15.4 ± 1.1 years, BMI percentile: 97.3 ± 3.3) were randomly assigned to interventions: control (C; n = 30), nutrition (N; n = 39, 1×/week focused on decreasing sugar and increasing fiber intake), or nutrition + strength training (N+ST; n = 31, 2×/week). The following were measured at pre- and postintervention: strength, dietary intake, body composition (dual-energy X-ray absorptiometry/magnetic resonance imaging) and glucose/insulin indexes (oral glucose tolerance test (OGTT)/intravenous glucose tolerance test (IVGTT)) and inflammatory markers. Overall, N compared to C and N+ST reported significant improvements in SI (+16.5% vs. -32.3% vs. -6.9% respectively, P < 0.01) and disposition index (DI: +15.5% vs. -14.2% vs. -13.7% respectively, P < 0.01). N+ST compared to C and N reported significant reductions in hepatic fat fraction (HFF: -27.3% vs. -4.3% vs. 0% respectively, P < 0.01). Compared to N, N+ST reported reductions in plasminogen activator inhibitor-1 (PAI-1) (-38.3% vs. +1.0%, P < 0.01) and resistin (-18.7% vs. +11.3%, P = 0.02). There were no intervention effects for all other measures of adiposity or inflammation. Significant intervention by ethnicity interactions were found for African Americans in the N group who reported increases in total fat mass, 2-h glucose and glucose incremental areas under the curve (IAUC) compared to Latinos (P's < 0.05). These interventions yielded differential effects with N reporting favorable improvements in SI and DI and N+ST reporting marked reductions in HFF and inflammation. Both ethnic groups had significant improvements in metabolic health; however some improvements were not seen in African Americans. 相似文献
996.
van Zundert B Izaurieta P Fritz E Alvarez FJ 《Journal of cellular biochemistry》2012,113(11):3301-3312
Amyotrophic lateral sclerosis (ALS) is a devastating paralytic disorder caused by dysfunction and degeneration of motor neurons starting in adulthood. Most of our knowledge about the pathophysiological mechanisms of ALS comes from transgenic mice models that emulate a subgroup of familial ALS cases (FALS), with mutations in the gene encoding superoxide dismutase (SOD1). In the more than 15 years since these mice were generated, a large number of abnormal cellular mechanisms underlying motor neuron degeneration have been identified, but to date this effort has led to few improvements in therapy, and no cure. Here, we consider that this surfeit of mechanisms is best interpreted by current insights that suggest a very early initiation of pathology in motor neurons, followed by a diversity of secondary cascades and compensatory mechanisms that mask symptoms for decades, until trauma and/or aging overloads their protective function. This view thus posits that adult‐onset ALS is the consequence of processes initiated during early development. In fact, motor neurons in neonatal mutant SOD mice display important alterations in their intrinsic electrical properties, synaptic inputs and morphology that are accompanied by subtle behavioral abnormalities. We consider evidence that human mutant SOD1 protein in neonatal hSOD1G93A mice instigates motor neuron degeneration by increasing persistent sodium currents and excitability, in turn altering synaptic circuits that control excessive motor neuron firing and leads to excitotoxicity. We also discuss how therapies that are aimed at suppressing abnormal neuronal activity might effectively mitigate or prevent the onset of irreversible neuronal damage in adulthood. J. Cell. Biochem. 113: 3301–3312, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
997.
998.
Much has been learned in recent years about the mechanisms by which breastfeeding improves child health and survival. However, there has been little progress in using these insights to improve pediatric care. The aim of this study was to review all clinical studies of lactoferrin (LF) in children in an effort to determine which interventions may improve pediatric care or require further research. We conducted a systematic and critical review of published literature and found 19 clinical studies that have used human or bovine LF for different outcomes: iron metabolisms and anemia (6 studies), fecal flora (5 studies), enteric infections (3 studies), common pediatric illnesses (1 study), immunomodulation (3 studies), and neonatal sepsis (1 study). Although the efficacies have varied in each trial, the main finding of all published studies is the safety of the intervention. Protection against enteric infections and neonatal sepsis are the most likely biologically relevant activities of LF in children. Future studies on neonatal sepsis should answer critically important questions. If the data from these sepsis studies are proven to be correct, it will profoundly affect the treatment of low birth weight neonates and will aid in the reduction of child mortality worldwide. 相似文献
999.
M Sciancalepore E Luin G Parato E Ren R Giniatullin E Fabbretti P Lorenzon 《Free radical biology & medicine》2012,53(7):1392-1398
Reactive oxygen species (ROS) and extracellular adenosine 5'-triphosphate (ATP) participate in autocrine and paracrine regulation in skeletal muscle. However, the link between these two signaling systems is not well established. Here, we studied cell proliferation as a possible consequence of the trophic effect of ATP in cultured skeletal mouse myoblasts and we tested the possibility that low concentrations of ROS represent the intermediate signaling molecule mediating this effect. Exposure to 10μM ATP increased proliferation of mouse myoblasts by ~20%. ATP also induced intracellular Ca(2+) oscillations, which were independent of extracellular Ca(2+). Both effects of ATP were prevented by suramin, a broad-spectrum purinergic P2 receptor antagonist. In contrast, the adenosine receptor blocker CGS-15943 did not modify the ATP-mediated effects. Consistent with this, adenosine per se did not change myoblast growth, indicating the direct action of ATP via P2 receptor activation. The proliferative effect of ATP was prevented after depletion of hydrogen peroxide (H(2)O(2)) by the peroxidase enzyme catalase. Low-micromolar concentrations of exogenous H(2)O(2) mimicked the stimulatory effect of ATP on myoblast growth. DCF imaging revealed ATP-induced catalase and DPI-sensitive ROS production in myoblasts. In conclusion, our results indicate that extracellular ATP controls mouse myoblast proliferation via induction of ROS generation. 相似文献
1000.
Incorporating clonal growth form clarifies the role of plant height in response to nitrogen addition
Gough L Gross KL Cleland EE Clark CM Collins SL Fargione JE Pennings SC Suding KN 《Oecologia》2012,169(4):1053-1062
Nutrient addition to grasslands consistently causes species richness declines and productivity increases. Competition, particularly for light, is often assumed to produce this result. Using a long-term dataset from North American herbaceous plant communities, we tested whether height and clonal growth form together predict responses to fertilization because neither trait alone predicted species loss in a previous analysis. Species with a tall-runner growth form commonly increased in relative abundance in response to added nitrogen, while short species and those with a tall-clumped clonal growth form often decreased. The ability to increase in size via vegetative spread across space, while simultaneously occupying the canopy, conferred competitive advantage, although typically only the abundance of a single species within each height-clonal growth form significantly responded to fertilization in each experiment. Classifying species on the basis of two traits (height and clonal growth form) increases our ability to predict species responses to fertilization compared to either trait alone in predominantly herbaceous plant communities. Electronic supplementary material The online version of this article (doi:10.1007/s00442-012-2264-5) contains supplementary material, which is available to authorized users. 相似文献