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191.
192.
Letícia Lintomen Gilberto Franchi Alexandre Nowill Antonio Condino-Neto Gilberto de Nucci Angelina Zanesco Edson Antunes 《BMC pulmonary medicine》2008,8(1):1-11
Background
Neutrophil products like matrix metalloproteinases (MMP), involved in bacterial defence mechanisms, possibly induce lung damage and are elevated locally during hospital- acquired pneumonia (HAP). In HAP the virulence of bacterial species is known to be different. The aim of this study was to investigate the influence of high-risk bacteria like S. aureus and pseudomonas species on pulmonary MMPconcentration in human pneumonia.Methods
In 37 patients with HAP and 16 controls, MMP-8, MMP-9 and tissue inhibitors of MMP (TIMP) were analysed by ELISA and MMP-9 activity using zymography in bronchoalveolar lavage (BAL).Results
MMP-9 activity in mini-BAL was increased in HAP patients versus controls (149 ± 41 vs. 34 ± 11, p < 0.0001). In subgroup analysis, the highest MMP concentrations and activity were seen in patients with high-risk bacteria: patients with high-risk bacteria MMP-9 1168 ± 266 vs. patients with low-risk bacteria 224 ± 119 ng/ml p < 0.0001, MMP-9 gelatinolytic activity 325 ± 106 vs. 67 ± 14, p < 0.0002. In addition, the MMP-8 and MMP-9 concentration was associated with the state of ventilation and systemic inflammatory marker like CRP.Conclusion
Pulmonary MMP concentrations and MMP activity are elevated in patients with HAP. This effect is most pronounced in patients with high-risk bacteria. Artificial ventilation may play an additional role in protease activation. 相似文献193.
Camila de Moraes Ana Paula Couto Davel Luciana Venturini Rossoni Edson Antunes Angelina Zanesco 《BMC physiology》2008,8(1):1-8
Background
Obesity has been associated with a variety of disease such as type II diabetes mellitus, arterial hypertension and atherosclerosis. Evidences have shown that exercise training promotes beneficial effects on these disorders, but the underlying mechanisms are not fully understood. The aim of this study was to investigate whether physical preconditioning prevents the deleterious effect of high caloric diet in vascular reactivity of rat aortic and mesenteric rings.Methods
Male Wistar rats were divided into sedentary (SD); trained (TR); sedentary diet (SDD) and trained diet (TRD) groups. Run training (RT) was performed in sessions of 60 min, 5 days/week for 12 weeks (70–80% VO2max). Triglycerides, glucose, insulin and nitrite/nitrate concentrations (NOx -) were measured. Concentration-response curves to acetylcholine (ACh) and sodium nitroprusside (SNP) were obtained. Expression of Cu/Zn superoxide dismutase (SOD-1) was assessed by Western blotting.Results
High caloric diet increased triglycerides concentration (SDD: 216 ± 25 mg/dl) and exercise training restored to the baseline value (TRD: 89 ± 9 mg/dl). Physical preconditioning significantly reduced insulin levels in both groups (TR: 0.54 ± 0.1 and TRD: 1.24 ± 0.3 ng/ml) as compared to sedentary animals (SD: 0.87 ± 0.1 and SDD: 2.57 ± 0.3 ng/ml). On the other hand, glucose concentration was slightly increased by high caloric diet, and RT did not modify this parameter (SD: 126 ± 6; TR: 140 ± 8; SDD: 156 ± 8 and TRD 153 ± 9 mg/dl). Neither high caloric diet nor RT modified NOx - levels (SD: 27 ± 4; TR: 28 ± 6; SDD: 27 ± 3 and TRD: 30 ± 2 μM). Functional assays showed that high caloric diet impaired the relaxing response to ACh in mesenteric (about 13%), but not in aortic rings. RT improved the relaxing responses to ACh either in aortic (28%, for TR and 16%, to TRD groups) or mesenteric rings (10%, for TR and 17%, to TRD groups) that was accompanied by up-regulation of SOD-1 expression and reduction in triglycerides levels.Conclusion
The improvement in endothelial function by physical preconditioning in mesenteric and aortic arteries from high caloric fed-rats was directly related to an increase in NO bioavailability to the smooth muscle mostly due to SOD-1 up regulation. 相似文献194.
Gomes C Palma AS Almeida R Regalla M McCluskey LF Trojanowski JQ Costa J 《Biotechnology letters》2008,30(4):603-610
The Golgi apparatus (GA) appears disrupted in motor neurons of amyotrophic lateral sclerosis (ALS). Here, mouse motor neuron-like
NSC-34 cell lines stably expressing human superoxide dismutase 1 (hSOD1)wt and mutant hSOD1G93A, as an ALS cell model, were constructed. The number of cells with disrupted GA increased from 14% to 34%. Furthermore, NSC-34/hSOD1G93A cells showed lower levels of proliferation and differentiation. GA disruption was not caused by apoptosis as determined by
several techniques including caspase-3 activation. Similarly, spinal cords from ALS patients did not show caspase-3 activation.
Therefore, NSC-34/hSOD1G93A cells are a suitable cell model to study GA dysfunction in ALS. 相似文献
195.
Oscar?Parravicini M.?Lucrecia?Bogado Sebastián?Rojas Emilio?L.?Angelina Sebastián?A.?Andujar Lucas?J.?Gutierrez Nuria?Cabedo M.?Jesús?Sanz M.?Pilar?López-Gresa Diego?Cortes Ricardo?D.?EnrizEmail author 《Journal of molecular modeling》2017,23(9):273
A series of tetrahydroisoquinolines functionalized with carbamates is reported here as highly selective ligands on the dopamine D2 receptor. These compounds were selected by means of a molecular modeling study. The studies were carried out in three stages: first an exploratory study was carried out using combined docking techniques and molecular dynamics simulations. According to these results, the bioassays were performed; these experimental studies corroborated the results obtained by molecular modeling. In the last stage of our study, a QTAIM analysis was performed in order to determine the main molecular interactions that stabilize the different ligand-receptor complexes. Our results show that the adequate use of combined simple techniques is a very useful tool to predict the potential affinity of new ligands at dopamine D1 and D2 receptors. In turn the QTAIM studies show that they are very useful to evaluate in detail the molecular interactions that stabilize the different ligand-receptor complexes; such information is crucial for the design of new ligands. 相似文献
196.
Eunice Y. Chen Thomas M. Olino Chris J. Conklin Feroze B. Mohamed W. Scott Hoge Gary D. Foster and the Genetic Neural Biomarkers of Obesity study group Jean M. Arlt Kalina Eneva Judy R. Kidd Kenneth R. Kidd Michelle R. Lent Susan Murray Andrew Newberg Colleen Tewksbury Stephanie S. VanderVeur Angelina Yiu 《Obesity (Silver Spring, Md.)》2017,25(1):66-75
197.
198.
Angelina DR Felix Mami Takahashi Rie Katsumata-Tsuboi Ryo Satoh Teoh Soon Hui 《Bioscience, biotechnology, and biochemistry》2017,81(11):2209-2211
Rice powder extract (RPE) from black and brown rice (Oryza sativa L. indica) improves hepatic lipid accumulation in obese and diabetic model mice via peroxisomal fatty acid oxidation. RPE showed PPARα agonistic activity which did not differ between black and brown RPE despite a higher anthocyanin content in black RPE. 相似文献
199.
Enhanced crude oil biodegradative potential of natural phytoplankton‐associated hydrocarbonoclastic bacteria 下载免费PDF全文
Haydn Thompson Angelina Angelova Bernard Bowler Martin Jones Tony Gutierrez 《Environmental microbiology》2017,19(7):2843-2861
Phytoplankton have been shown to harbour a diversity of hydrocarbonoclastic bacteria (HCB), yet it is not understood how these phytoplankton‐associated HCB would respond in the event of an oil spill at sea. Here, we assess the diversity and dynamics of the bacterial community associated with a natural population of marine phytoplankton under oil spill‐simulated conditions, and compare it to that of the free‐living (non phytoplankton‐associated) bacterial community. While the crude oil severely impacted the phytoplankton population and was likely conducive to marine oil snow formation, analysis of the MiSeq‐derived 16S rRNA data revealed dramatic and differential shifts in the oil‐amended communities that included blooms of recognized HCB (e.g., Thalassospira, Cycloclasticus), including putative novel phyla, as well as other groups with previously unqualified oil‐degrading potential (Olleya, Winogradskyella, and members of the inconspicuous BD7‐3 phylum). Notably, the oil biodegradation potential of the phytoplankton‐associated community exceeded that of the free‐living community, and it showed a preference to degrade substituted and non‐substituted polycyclic aromatic hydrocarbons. Our study provides evidence of compartmentalization of hydrocarbon‐degrading capacity in the marine water column, wherein HCB associated with phytoplankton are better tuned to degrading crude oil hydrocarbons than that by the community of planktonic free‐living bacteria. 相似文献
200.
Reconstitution of Cyclin D1-Associated Kinase Activity Drives Terminally Differentiated Cells into the Cell Cycle 总被引:6,自引:0,他引:6 下载免费PDF全文
Lucia Latella Alessandra Sacco Deborah Pajalunga Marianne Tiainen Daniela Macera Marco D''''Angelo Angelina Felici Ada Sacchi Marco Crescenzi 《Molecular and cellular biology》2001,21(16):5631-5643
Terminal cell differentiation entails definitive withdrawal from the cell cycle. Although most of the cells of an adult mammal are terminally differentiated, the molecular mechanisms preserving the postmitotic state are insufficiently understood. Terminally differentiated skeletal muscle cells, or myotubes, are a prototypic terminally differentiated system. We previously identified a mid-G(1) block preventing myotubes from progressing beyond this point in the cell cycle. In this work, we set out to define the molecular basis of such a block. It is shown here that overexpression of highly active cyclin E and cdk2 in myotubes induces phosphorylation of pRb but cannot reactivate DNA synthesis, underscoring the tightness of cell cycle control in postmitotic cells. In contrast, forced expression of cyclin D1 and wild-type or dominant-negative cdk4 in myotubes restores physiological levels of cdk4 kinase activity, allowing progression through the cell cycle. Such reactivation occurs in myotubes derived from primary, as well as established, C2C12 myoblasts and is accompanied by impairment of muscle-specific gene expression. Other terminally differentiated systems as diverse as adipocytes and nerve cells are similarly reactivated. Thus, the present results indicate that the suppression of cyclin D1-associated kinase activity is of crucial importance for the maintenance of the postmitotic state in widely divergent terminally differentiated cell types. 相似文献