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331.
Michaelidis B Kyriakopoulou-Sklavounou P Staikou A Papathanasiou I Konstantinou K 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2008,151(4):582-589
The present work aimed to contribute to the understanding of the adaptation of the glycolytic pathway in tissues of frog Rana ridibunda and land snail species Helix lucorum during seasonal hibernation. Moreover responses of glycolytic enzymes from cold acclimated R. ridibunda and H. lucorum were studied as well. The drop in Po2 in the blood of hibernated frogs and land snails indicated lower oxygen consumption and a decrease in their metabolic rate. The activities of glycolytic enzymes indicated that hibernation had a differential effect on the glycolyis in the two species studied and also in the tissues of the same species. The activity of l-LDH decreased significantly in the skeletal muscle and heart of hibernated R. ridibunda indicating a low glycolytic potential. Similar biochemical responses were observed in the same tissues during cold acclimation. The continuous increase in the activities of glycolytic enzymes studied, except for HK, might indicate a compensation for the impacts of low temperature on the enzymatic activities. In contrast to R. ridibunda, the activities of the enzymes increased and remained at higher levels than those of the prehibernation controls indicating maintenance of glycolytic potential in the tissues of hibernating land snails. 相似文献
332.
Berthold HK Unverdorben S Degenhardt R Unverdorben M Gouni-Berthold I 《Obesity (Silver Spring, Md.)》2008,16(10):2272-2280
CM3, a highly cross-linked cellulose in capsule form, expands in the stomach to a size several fold of its original volume. It is purported to induce a prolonged feeling of satiation and a delay in gastric emptying, thus promoting weight loss. We examined whether CM3 delays gastric emptying (using the stable isotope (13)C-octanoic breath test) and whether it influences subjective feelings of appetite sensations (using visual analog scales, VASs). We performed a double-blind randomized placebo-controlled crossover trial in 19 moderately obese but otherwise healthy subjects (mean age 55 +/- 9 years, BMI 31.1 +/- 4.6 kg/m(2)). The subjects were treated with six capsules of CM3 or matching placebo 30 min before a standardized solid meal. Breath collection and VASs were performed over 4 h every 15 min and 30 min, respectively. Half-excretion time of (13)CO(2) in breath, indicating gastric emptying half time, was the primary outcome parameter. The study was powered to detect a change in gastric emptying of 20-30 min. Mean (13)CO(2) half-excretion time changed from 2.3 +/- 0.4 to 2.4 +/- 0.33 h (mean difference +6 min, 95% confidence interval (CI) -3 to +15 min; P = 0.17). Appetite sensations (hunger, satiation, fullness, prospective food consumption, desire to eat something sweet, salty, savory, or fatty) changed over time during the course of the postprandial phase but were not influenced by CM3 (repeated measures ANOVA). In obese subjects, acute administration of the weight-loss supplement CM3 does not delay gastric emptying and does not influence subjective appetite sensations. 相似文献
333.
334.
Panteleon V Kostakis IK Marakos P Pouli N Andreadou I 《Bioorganic & medicinal chemistry letters》2008,18(21):5781-5784
A series of novel spiro-substituted 4-hydroxypyranocoumarins and their corresponding dihydropyrano cis-diols has been synthesized. Among them the spiroadamantylpyranocoumarin and the diols can interact with the stable free radical 1,1-diphenyl-2-picrylhydrazyl and scavenge superoxide anions generated in the xanthine-xanthine oxidase system. 相似文献
335.
Illig CR Chen J Wall MJ Wilson KJ Ballentine SK Rudolph MJ DesJarlais RL Chen Y Schubert C Petrounia I Crysler CS Molloy CJ Chaikin MA Manthey CL Player MR Tomczuk BE Meegalla SK 《Bioorganic & medicinal chemistry letters》2008,18(5):1642-1648
The optimization of the arylamide lead 2 resulted in identification of a highly potent series of 2,4-disubstituted arylamides. Compound 8 (FMS kinase IC(50)=0.0008 microM) served as a proof-of-concept candidate in a collagen-induced model of arthritis in mice. 相似文献
336.
Th1/Th2 cytokine pattern in bronchoalveolar lavage fluid and induced sputum in pulmonary sarcoidosis
Ioanna Tsiligianni Katerina M Antoniou Despina Kyriakou Nikolaos Tzanakis George Chrysofakis Nikolaos M Siafakas Demosthenes Bouros 《BMC pulmonary medicine》2005,5(1):1-6
Background
Recent studies suggest that angiotensin-converting enzyme (ACE) inhibitors may have beneficial effects for patients at risk for some types of infections. We examined the effect of prior outpatient use of ACE inhibitors on mortality for patients hospitalized with community-acquired pneumonia.Methods
A retrospective cohort study conducted at two tertiary teaching hospitals. Eligible subjects were admitted with a diagnosis of, had a chest x-ray consistent with, and had a discharge ICD-9 diagnosis of pneumonia. Subjects were excluded if they were "comfort measures only" or transferred from another acute care hospital. Subjects were considered to be on a medication if they were taking it at the time of presentation.Results
Data was abstracted on 787 subjects at the two hospitals. Mortality was 9.2% at 30-days and 13.6% at 90-days. At presentation 52% of subjects were low risk, 34% were moderate risk, and 14% were high risk. In the multivariable conditional logistic regression analysis, after adjusting for potential confounders, the use of ACE inhibitors at presentation (odds ratio 0.44, 95% confidence interval 0.22–0.89) was significantly associated with 30-day mortality.Conclusion
Prior outpatient use of an ACE inhibitor was associated with decreased mortality in patients hospitalized with community-acquired pneumonia despite their use being associated with comorbid illnesses likely to contribute to increased mortality. Confirmatory studies are needed, as well as research to determine the mechanism(s) of this protective effect. 相似文献337.
338.
Callac P Jacobé de Haut I Imbernon M Guinberteau J Desmerger C Theochari I 《Mycologia》2003,95(2):222-231
Among 400 wild specimens of A. bisporus collected in Europe, only three were tetrasporic. In the case of two of them from France, a previous study showed that one was homokaryotic and hypothetically belonged to a homothallic entity while the other was heterokaryotic and possibly resulted from hybridization between a member of this entity and a classical bisporic strain. A third tetrasporic specimen recently was discovered in Greece. Morphological and genetic comparisons, using alloenzymatic markers, molecular markers and ITS polymorphisms, reveal that this third specimen is homokaryotic and belongs, with the homokaryotic specimen from France, to the same entity. Dissimilarity analysis confirms the hybrid origin of the heterokaryotic specimen. Varietal status is proposed for this homothallic, highly homogeneous entity, and A. bisporus var. eurotetrasporus is described. This novel variety clearly differs from var. bisporus by its tetrasporic basidia and from var. burnettii by its longer spores. It has a complex story because it can interbreed with var. bisporus and shares the same habitat; however, because of its homothallic life cycle and its partial intersterility, it is probably in the process of speciation. 相似文献
339.
Structural and functional roles of desmin in mouse skeletal muscle during passive deformation 总被引:6,自引:0,他引:6
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Shah SB Davis J Weisleder N Kostavassili I McCulloch AD Ralston E Capetanaki Y Lieber RL 《Biophysical journal》2004,86(5):2993-3008
Mechanical interactions between desmin and Z-disks, costameres, and nuclei were measured during passive deformation of single muscle cells. Image processing and continuum kinematics were used to quantify the structural connectivity among these structures. Analysis of both wild-type and desmin-null fibers revealed that the costamere protein talin colocalized with the Z-disk protein alpha-actinin, even at very high strains and stresses. These data indicate that desmin is not essential for mechanical coupling of the costamere complex and the sarcomere lattice. Within the sarcomere lattice, significant differences in myofibrillar connectivity were revealed between passively deformed wild-type and desmin-null fibers. Connectivity in wild-type fibers was significantly greater compared to desmin-null fibers, demonstrating a significant functional connection between myofibrils that requires desmin. Passive mechanical analysis revealed that desmin may be partially responsible for regulating fiber volume, and consequently, fiber mechanical properties. Kinematic analysis of alpha-actinin strain fields revealed that knockout fibers transmitted less shear strain compared to wild-type fibers and experienced a slight increase in fiber volume. Finally, linkage of desmin intermediate filaments to muscle nuclei was strongly suggested based on extensive loss of nuclei positioning in the absence of desmin during passive fiber loading. 相似文献
340.
Anastassopoulou I Banci L Bertini I Cantini F Katsari E Rosato A 《Biochemistry》2004,43(41):13046-13053
The human metallochaperone HAH1 has been produced in Escherichia coli with four additional amino acids at the C-terminus and characterized in solution by NMR spectroscopy, both with and without copper(I). The solution structure of the apo-HAH1 monomer has a root-mean-square-deviation (RMSD) of 0.50 A for the coordinates of the backbone atoms and 0.96 A for all heavy atoms. These values compare, respectively, with 0.45 and 0.95 A for copper(I)-HAH1. There are only minor structural rearrangements upon copper(I) binding. In particular, the variation of interatomic interactions around the metal-binding region is limited to a movement of Lys60 toward the metal site. The protein structures are similar to those obtained by X-ray crystallography in a variety of derivatives, with backbone RMSD values below 1 A. In the holoprotein, copper(I) is confirmed to be two coordinated. If these data are compared with those of orthologue proteins, we learn that HAH1 has a lower tendency to change coordination number from two to three. Such a switch in coordination is a key step in copper transfer. 相似文献