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201.
N T Eissa V M Ranieri C Corbeil M Chassé F M Robatto J Braidy J Milic-Emili 《Journal of applied physiology》1991,70(6):2719-2729
The effects of inspiratory flow (V) and inflation volume (delta V) on the mechanical properties of the respiratory system in eight ARDS patients were investigated using the technique of rapid airway occlusion during constant-flow inflation. We measured interrupter resistance (Rint,rs), which in humans represents airway resistance, the additional resistance (delta Rrs) due to viscoelastic pressure dissipations and time constant inequalities, and static (Est,rs) and dynamic (Edyn,rs) elastance. The results were compared with a previous study on 16 normal anesthetized paralyzed humans (D'Angelo et al. J. Appl. Physiol. 67: 2556-2564, 1989). We observed that 1) resistance and elastance were higher in ARDS patients; 2) with increasing V, Rint,rs and Est,rs did not change, delta Rrs decreased progressively, and Edyn,rs increased progressively; 3) with increasing delta V, Rint,rs decreased slightly, delta Rrs increased progressively, and Est,rs and Edyn,rs showed an initial decrease followed by a secondary increase noted only in the ARDS patients. The above findings could be explained in terms of a model incorporating a standard resistance in parallel with a standard elastance and a series spring-and-dashpot body that represents the stress adaptation units within the tissues of the respiratory system. 相似文献
202.
D Kanduc A Aresta M R Rossiello T Ranieri E Quagliariello 《Biochemical and biophysical research communications》1989,163(3):1412-1417
The effect of carcinogens given by a single or multiple injections on the extent of (35S)methionine interaction with hepatic tRNA was studied in normal and partially hepatectomized rats. Either partial hepatectomy or administration of ethionine (100 or 330 mg/kg body weight) and dimethylnitrosamine (120 mg/kg body weight) by multiple i.p. injections inhibited the (35S)methionine-tRNA interaction, while administration of hepatocarcinogenic chemicals plus PH resulted rather in a stimulation. Methylnitrosourea enhanced the extent of interaction when administered in a single dose (100 mg per kg body weight) 18 h after partial hepatectomy. 相似文献
203.
Abbandonato G Signore G Nifosì R Voliani V Bizzarri R Beltram F 《European biophysics journal : EBJ》2011,40(11):1205-1214
The photoswitching behaviour of the green fluorescent protein (GFP) chromophore and its analogs opens up exciting horizons
for the engineering and development of molecular devices for high sensitivity in vivo studies. In this work we present the
synthesis and photophysical study of four GFP chromophore analogs belonging to butenolide and pyrrolinone classes. These chromophores
possess an intriguing photoinduced cis–trans isomerization mechanism. Stereochemical structural assignment was unambiguously performed by 1D Nuclear Overhauser Effect
NMR measurements. The spectroscopic properties of both cis and trans isomers were studied, and photoconversion quantum yield for cis–trans isomerization was assessed to be in the 0.1–0.4 range. Finally, the 3JC,H coupling constant in the 13C–C=C–H motif was in excellent agreement with theoretical DFT calculations, thus providing a further confirmation of cis–trans photoisomerization of the structurally analog GFP chromophore. 相似文献
204.
In this review, we present a comprehensive overview of the molecular studies on human tropoelastin domains accomplished by Tamburro and co-workers in the last decade. The used approach is the reductionist approach applied to human tropoelastin and is based on the observation that the tropoelastin gene exhibits a cassette-like organization, with a regular alternation of cross-linking and hydrophobic domains putatively responsible for the elasticity of the protein. The peculiar structure of human tropoelastin gene prompted us to study the isolated domains encoded by the exons of tropoelastin, with the perspective to get deep insights into the structural properties of the whole protein. At the molecular level, the results clearly evidence large flexibility of the polypeptide chains in the hydrophobic domains, which oscillate between rather extended and folded conformations. An important role was assigned to poly-proline II conformation considered as the hinge structure in the dynamic conformational equilibrium suggested for the hydrophobic domains. For the lysine-rich cross-linking domains, the structural studies exactly localized α-helix along the polypeptide sequence. Furthermore, at supramolecular level, these studies showed that several domains are able to self-assemble in two different aggregation patterns, the fibrous elastin-like structure for some proline-rich hydrophobic domains and the amyloid-like for some glycine-rich hydrophobic domains. Accordingly, the studies suggest that the reductionist approach was a valid tool for studying a complex protein, such as elastin, elucidating not only the structure but also the specific role played by its constituent domains. 相似文献
205.
Ulivi V Lenti M Gentili C Marcolongo G Cancedda R Descalzi Cancedda F 《Arthritis research & therapy》2011,13(3):R92
Introduction
The mono- and digalactosyldiacylglycerol (MGDG and DGDG) galactolipids have been purified from the thermophilic blue-green alga Phormidium sp. ETS-05 that colonizes the therapeutic thermal mud of Abano Terme and Montegrotto Terme, Italy. Both compounds present a marked composition in polyunsaturated fatty acids, mainly omega-3. The therapeutic thermal mud is applied mainly to osteoarthritic cartilage patients. In the present study the effect of MGDG treatment on proteins and factors expressed by human articular cartilage cells in culture and on pathways activated in inflammatory conditions was studied. 相似文献206.
207.
Danilo Ranieri Salvatore Raffa Andrea Parente Simone Rossi Del Monte Vincenzo Ziparo Maria Rosaria Torrisi 《PloS one》2013,8(2)
The role of the mesothelial layer in the peritoneal spreading of cancer cells is only partially clarified. Here we attempted to better define the mesothelial contribution to the tumor cell adhesion using a direct adhesion test applied to human primary cultures of mesothelial cells (HPMCs) derived from the peritoneal washes of patients with gastric and colorectal cancers. Gastric and colon carcinoma cells were seeded on different mesothelial monolayers and quantitative fluorescence analysis was performed to analyze their growth and adhesive properties. The adhesion of the cancer cells was not affected by the origin of the HPMCs when derived from patients with different cancers or with benign disease. In contrast, the high levels of ICAM1 expression and ROS production, which characterize these senescent mesothelial cells, enhanced the tumor cell adhesion. These results suggest that the mesothelial adhesive properties are dependent on the cell senescence, while are not affected by the tumor environment. The use of peritoneal washes as a source to isolate HPMCs provides a practical and reliable tool for the in vitro analysis of the mesothelial conditions affecting the peritoneal carcinomatosis. 相似文献
208.
Elastin-like polypeptides adopt complex supramolecular structures, showing either a hydrophobic or a hydrophilic surface, depending on their surrounding environment and the supporting substrate. The preferred organization is important in many situations ranging from biocompatibility to bio-function. Here we compare the n-repeat pentamer LeuGlyGlyValGly (n = 7) with the analogue ValGlyGlyValGly (n = 5), as water suspensions and as deposits on silicon substrates. These sequences contain the repeat XxxGlyGlyZzzGly (Xxx, Zzz = Val, Leu) motif belonging to the hydrophobic glycine-rich domain of elastin and represent a simplified model from which to obtain information on molecular interactions functional to elastin itself. The compounds studied differ only by the presence of the -CH(2)- spacer in the Leu moiety and thus the work was aimed at revealing the influence of this spacer element on self assembly. Both polypeptides were studied under identical conditions, using combined techniques, to identify differences in their conformational states both at molecular (CD, FTIR) and supramolecular (XPS, AFM) levels. By these means, together with a Congo Red spectroscopic assay of β-sheet formation in water, a clear correlation between amino acid sequences (sequence specificity) and their kinetics and ordering of aggregation has emerged. The novel outcomes of this work are from the supplementary measurements, made to augment the AFM and XPS studies, showing that the significant step in the self assembly of both polypeptides takes place in the liquid phase and from the finding that the substitution of Val by Leu in the first position of the pentapeptide effectively inhibits the formation of amyloidal fibers. 相似文献
209.
Stynen AP Lage AP Moore RJ Rezende AM de Resende VD Ruy Pde C Daher N Resende Dde M de Almeida SS Soares Sde C de Abreu VA Rocha AA dos Santos AR Barbosa EG Costa DF Dorella FA Miyoshi A de Lima AR Campos FD de Sá PG Lopes TS Rodrigues RM Carneiro AR Leão T Cerdeira LT Ramos RT Silva A Azevedo V Ruiz JC 《Journal of bacteriology》2011,193(20):5871-5872
Campylobacter fetus subsp. venerealis is the etiologic agent of bovine genital campylobacteriosis, a sexually transmitted disease of cattle that is of worldwide importance. The complete sequencing and annotation of the genome of the type strain C. fetus subsp. venerealis NCTC 10354(T) are reported. 相似文献
210.
Domenico Ribatti Girolamo Ranieri Tiziana Annese Beatrice Nico 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014