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41.
Ernst K R?dland Morten Mattingsdal Ole K Olstad Reidun Ovsteb? Peter Kierulf Fredrik Muller Stig S Fr?land 《Medical mycology》2008,46(4):327-336
The objective of these studies was to investigate genes of importance in the pathogenesis of Aspergillus infections. To do so, we employed microarray methodology to explore gene expression in human monocytes infected with Aspergillus conidia as compared with unstimulated monocytes and those stimulated with lipopolysaccharide (LPS) signaling through TOLL-like receptor 4 (TLR4). We found 997 (P相似文献
42.
Larsen MV Lundegaard C Lamberth K Buus S Brunak S Lund O Nielsen M 《European journal of immunology》2005,35(8):2295-2303
Reverse immunogenetic approaches attempt to optimize the selection of candidate epitopes, and thus minimize the experimental effort needed to identify new epitopes. When predicting cytotoxic T cell epitopes, the main focus has been on the highly specific MHC class I binding event. Methods have also been developed for predicting the antigen-processing steps preceding MHC class I binding, including proteasomal cleavage and transporter associated with antigen processing (TAP) transport efficiency. Here, we use a dataset obtained from the SYFPEITHI database to show that a method integrating predictions of MHC class I binding affinity, TAP transport efficiency, and C-terminal proteasomal cleavage outperforms any of the individual methods. Using an independent evaluation dataset of HIV epitopes from the Los Alamos database, the validity of the integrated method is confirmed. The performance of the integrated method is found to be significantly higher than that of the two publicly available prediction methods BIMAS and SYFPEITHI. To identify 85% of the epitopes in the HIV dataset, 9% and 10% of all possible nonamers in the HIV proteins must be tested when using the BIMAS and SYFPEITHI methods, respectively, for the selection of candidate epitopes. This number is reduced to 7% when using the integrated method. In practical terms, this means that the experimental effort needed to identify an epitope in a hypothetical protein with 85% probability is reduced by 20-30% when using the integrated method.The method is available at http://www.cbs.dtu.dk/services/NetCTL. Supplementary material is available at http://www.cbs.dtu.dk/suppl/immunology/CTL.php. 相似文献
43.
Anders Rinnov Nielsen Remi Mounier Peter Plomgaard Ole Hartvig Mortensen Milena Penkowa Tobias Speerschneider Henriette Pilegaard Bente Klarlund Pedersen 《The Journal of physiology》2007,584(1):305-312
The cytokine interleukin-15 (IL-15) has been demonstrated to have anabolic effects in cell culture systems. We tested the hypothesis that IL-15 is predominantly expressed by type 2 skeletal muscle fibres, and that resistance exercise regulates IL-15 expression in muscle. Triceps brachii, vastus lateralis quadriceps and soleus muscle biopsies were obtained from normally physically active, healthy, young male volunteers ( n = 14), because these muscles are characterized by having different fibre-type compositions. In addition, healthy, normally physically active male subjects ( n = 8) not involved in any kind of resistance exercise underwent a heavy resistance exercise protocol that stimulated the vastus lateralis muscle and biopsies were obtained from this muscle pre-exercise as well as 6, 24 and 48 h post-exercise. IL-15 mRNA levels were twofold higher in the triceps (type 2 fibre dominance) compared with the soleus muscle (type 1 fibre dominance), but Western blotting and immunohistochemistry revealed that muscle IL-15 protein content did not differ between triceps brachii, quadriceps and soleus muscles. Following resistance exercise, IL-15 mRNA levels were up-regulated twofold at 24 h of recovery without any changes in muscle IL-15 protein content or plasma IL-15 at any of the investigated time points. In conclusion, IL-15 mRNA level is enhanced in skeletal muscles dominated by type 2 fibres and resistance exercise induces increased muscular IL-15 mRNA levels. IL-15 mRNA levels in skeletal muscle were not paralleled by similar changes in muscular IL-15 protein expression suggesting that muscle IL-15 may exist in a translationally inactive pool. 相似文献
44.
Svend Davanger Jon Storm-Mathisen Ole Petter Ottersen 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1994,98(2):342-354
Human retinae from surgical specimens rapidly fixed in a glutaraldehyde/formaldehyde mixture were subjected to postembedding, immunogold immunocytochemistry of glutamate and glycine, and subsequently analysed in an electron microscope. The two amino acids were visualised in the same tissue sections by the use of two different gold particle sizes. All bipolar cell perikarya and terminals showed significant glutamate labelling with mean gold particle densities 3–4 times higher than those of the retinal, non-neural pigment epithelial and Müller cells. Bipolar cell terminals displayed significantly higher glutamate labelling density than the bipolar cell bodies, as would be expected of glutamatergic neurons. A subpopulation of the glutamate-immunolabelled bipolar cell bodies (18%) and terminals (32%) also exhibited strong glycine labelling (7–8 times that of pigment epithelial and Müller cells). These glutamate-glycine positive terminals established contacts with amacrine cell processes and ganglion cell dendrites and were localised almost exclusively at between 44% and 88% depth of the inner plexiform layer, indicating that they belong to the ON cone bipolar system. This subpopulation of terminals was endowed with significantly higher glycine labelling density than the glycine positive bipolar cell bodies. These results show that human bipolar cell terminals colocalise glutamate and glycine and provide the first direct demonstration of an enrichment of these two amino acids in the same presynaptic element. 相似文献
45.
Ole Rintek Madsen Ulrik Birk Lauridsen Andreas Hartkopp Ole Helmer Sørensen 《European journal of applied physiology》1997,75(3):239-245
Dual energy x-ray absorptiometry (DEXA) offers the possibility of assessing regional soft tissue composition, i.e. lean mass (LM) and fat mass : LM may be considered a measure of muscle mass. We examined age-related differences in LM, percentage fat (%fat) and muscle strength in 100 healthy non-athletic women aged 18–87 years. Relationships between muscle strength and leg LM in 20 elite female weight lifters and in 18 inactive women with previous hip fractures were also studied. The LM and %fat of the whole body, trunk, arms and legs were derived from a whole body DEXA scan. Isokinetic knee extensor strength (KES) and flexor strength (KFS) at 30°?·?s–1 were assessed using an isokinetic dynamometer. The women aged 71–87 years had 35% lower KES and KFS than the women aged 18–40 years (P 0.0001). Differences in LM were less pronounced. The LM of the legs, for instance, was 15% lower in the old than in the young women (P 0.0001). In a multiple regression analysis with age, body mass, height and leg LM or KES as independent variables and KES or leg LM as the dependent variable, age was the most important predictor of KES (r partial?=??0.74, P 0.0001). The same applied to KFS. Body mass, not age, was the most important predictor of leg LM (r partial?=?0.65, P 0.0001) and of LM at all other measurement sites. The LM measured at different regions decreased equally with increasing age. The KES:leg LM ratio was negatively correlated with age (r?=??0.70, P 0.0001). The weight lifters had significantly higher KES:leg LM ratios than age-matched controls (+12%, P 0.0001) and vice versa for the women with previous hip fractures (–36%, P 0.0001). In conclusion, from our study it would seem that in healthy nonathletic women, age is a more important determinant of muscle strength than is LM as measured by DEXA. Muscle strengthening exercises and inactivity seem to have a considerably stronger influence on muscle strength than on LM. 相似文献
46.
Maximum effort flow-static recoil curves were obtained in 5 healthy subjects breathing air, He/O2, and SF6/O2 mixtures. In 4 of them maximum effort flows corresponded to really maximal flows and their curves were transformed into compliance curves for the flow limiting segments of the airway and analyzed from the point of view of a previously presented lung model (Pedersen and Nielsen 1976). The results showed, that viscosity dependent pressure losses from the alveoli to the flow limiting segments were minimal for air and SF6/O2, but not for He/O2. When viscosity dependent pressure losses could be neglected, then expiration of gases of different densities gave almost identical compliance curves for the flow limiting segments. This supported the applicability of the model. The calculated compliance curves for the flow limiting segments were compared with data from the literature, and the findings indicated that flow limitation during expirations with just maximal flows throughout began in the extrapulmonary airways and moved upstream during the expiration. 相似文献
47.
48.
Ole Holger Petersen 《Pflügers Archiv : European journal of physiology》1971,323(2):91-95
Summary The cat submandibular gland was perfused with a normal NaCl Locke solution and a chloride-free sucrose solution. The numerical increase in acinar membrane potential (secretory potential) was recorded after intra-arterial injection of acetylcholine.There was no significant difference between the size of the secretory potentials recorded during perfusion with the sucrose solution [23.6 mV±1.4 (n=23)] and the size of those recorded during the control periods [20.6 mV±1.2 (n=24)].The maximal value of the membrane potential after injection of acetylcholine was higher [51.8 mV±2.4 (n=23)] during perfusion with the sucrose solution than during the control periods [44.8 mV±1.8 (n=22)].The results show that a pump transporting chloride into the acinar cells cannot be responsible for the generation of the secretory potentials. The results are best accounted for by assuming that an outward passive transport of potassium, being partly short-circuited by an inward passive sodium transport, is responsible for the change in membrane potential after stimulation with acetylcholine.Supported by the Danish State Research Foundation and Johann and Hanne Weimann's legate. 相似文献
49.
50.
Uffe A. Brodthagen Knud NØrregaard Hansen Jens Bjerre Knudsen Robert Jordal Ole Kristensen Poul -Erik Paulev 《European journal of applied physiology》1985,53(4):334-338
Summary 20 male elite long distance runners were compared to a control group of blood donors to determine the effect of training on red blood cells. The acute effects of exercise on red cells were investigated in 11 of the runners following a race of 15–30 km. The runners had elevated resting values of red cell 2,3-DPG (P<0.05) and mean cell volume (P<0.01); blood Hb and ATP were not different from concentrations in the control group. The red cell status of the athletes may be explained by an increased proportion of young erythrocytes in runners. No statistically significant changes in red cell 2,3-DPG, ATP, mean cell volume or blood Hb were found post exercise. 相似文献