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41.
Jaume?Pons Jaume?Sauleda Verónica?Regueiro Carmen?Santos Meritxell?López Joana?Ferrer Alvar?GN?Agustí José?A?BengoecheaEmail author 《Respiratory research》2006,7(1):64
Background
Chronic obstructive pulmonary disease (COPD) is characterised by pulmonary and systemic inflammation which flare-up during episodes of acute exacerbation (AECOPD). Given the role of Toll-like receptors (TLRs) in the induction of inflammatory responses we investigated the involvement of TLRs in COPD pathogenesis.Methods
The expression of TLR-2, TLR-4 and CD14 in monocytes was analyzed by flow cytometry. To study the functional responses of these receptors, monocytes were stimulated with peptidoglycan or lipopolysaccharide and the amounts of TNFα and IL-6 secreted were determined by ELISA.Results
We found that the expression of TLR-2 was up-regulated in peripheral blood monocytes from COPD patients, either clinically stable or during AECOPD, as compared to never smokers or smokers with normal lung function. Upon stimulation with TLR-2 ligand monocytes from COPD patients secreted increased amounts of cytokines than similarly stimulated monocytes from never smokers and smokers. In contrast, the expressions of TLR-4 and CD14 were not significantly different between groups, and the response to lipopolysaccharide (a TLR-4 ligand) stimulation was not significantly different either. At discharge from hospital TLR-2 expression was down-regulated in peripheral blood monocytes from AECOPD patients. This could be due to the treatment with systemic steroids because, in vitro, steroids down-regulated TLR-2 expression in a dose-dependent manner. Finally, we demonstrated that IL-6, whose plasma levels are elevated in patients, up-regulated in vitro TLR-2 expression in monocytes from never smokers.Conclusion
Our results reveal abnormalities in TLRs expression in COPD patients and highlight its potential relationship with systemic inflammation in these patients.42.
Peterson MD Alvar BA Rhea MR 《Journal of strength and conditioning research / National Strength & Conditioning Association》2006,20(4):867-873
Critical to multidimensional sport conditioning is a systematic knowledge of the interactions between fitness components, as well as the transference relationships to performance. The purpose of this investigation was to examine the relationships between lower body muscular strength and several fundamental explosive performance measures. Fifty-four men and women collegiate athletes were tested to determine (a) lower-body muscular strength (1 repetition maximum barbell back squat), (b) countermovement vertical jump height and peak power output, (c) standing broad jump distance, (d) agility (cone T-test time), (e) sprint acceleration (m.s(-2)), and (f) sprint velocity (m.s(-1)). Analyses were performed using Pearson r correlations to examine these relationships. Partial correlations tested for relationships between performance measures while controlling for muscular strength. T-tests were performed to assess the difference between men and women. Correlation data demonstrated that significant (p < 0.01) strong linear relationships were indicated between muscular strength and power, as well as every sport-performance field tests. However, when controlling for strength with partial correlation, each of these relationships appreciably diminished. Significant differences (p < 0.05) were found between men and women for each of the performance tests. Muscular strength, peak power output, vertical jumping ability, standing broad jump, agility, sprint acceleration, and sprint velocity were all shown to be very highly related. Further examination demonstrated that body mass-adjusted muscular strength is more highly related to performance measures than is absolute muscular strength. Current correlation data provide a quantified look at the interaction between muscular fitness components, as well as the transfer relationship to several athletic-specific performance measures. 相似文献
43.
A method is described for the development of DNA markers for detection of Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) in predator gut analysis, based on sequence characterized amplified regions (SCARs) derived from a randomly amplified polymorphic DNA (RAPD) band. A 1200-bp DNA fragment of H. armigera, absent in the predator band pattern and in other closely related prey species, was identified by RAPD analysis. This fragment was cloned and its extremes sequenced to design extended strand-specific 20-mer oligonucleotide primers. Three pairs of SCAR primers, which amplified three different DNA fragments, were used to study the effect of fragment length on detection of prey in the predator gut. Using the pair of primers that amplified the longest fragment of H. armigera DNA, a single band of 1100 bp was obtained, but its detection was not possible in the predator gut. Detection of the ingested prey was possible with the other two pairs of SCAR primers, obtaining bands of 600 and 254 bp, respectively. Detection of H. armigera DNA in the gut of the predator Dicyphus tamaninii was evaluated immediately after ingestion (t = 0) and after 4 h. Detection of H. armigera DNA after 4 h was only possible using the pair of primers that amplified the shortest fragment (254 bp). The test for specificity, using these last pair of primers, showed that H. armigera was the only species detected. The detection threshold was defined at a 1:8192 dilution of a H. armigera whole egg in all samples. 相似文献
44.
Mironov AA Mironov AA Beznoussenko GV Trucco A Lupetti P Smith JD Geerts WJ Koster AJ Burger KN Martone ME Deerinck TJ Ellisman MH Luini A 《Developmental cell》2003,5(4):583-594
Protein transport between the ER and the Golgi in mammalian cells occurs via large pleiomorphic carriers, and most current models suggest that these are formed by the fusion of small ER-derived COPII vesicles. We have examined the dynamics and structural features of these carriers during and after their formation from the ER by correlative video/light electron microscopy and tomography. We found that saccular carriers containing either the large supramolecular cargo procollagen or the small diffusible cargo protein VSVG arise through cargo concentration and direct en bloc protrusion of specialized ER domains in the vicinity of COPII-coated exit sites. This formation process is COPII dependent but does not involve budding and fusion of COPII-dependent vesicles. Fully protruded saccules then move centripetally, evolving into one of two types of carriers (with distinct kinetic and structural features). These findings provide an alternative framework for analysis of ER-to-Golgi traffic. 相似文献
45.
CA 125 in biological fluids 总被引:14,自引:0,他引:14
Molina R Filella X Jo J Agusti C Ballesta AM 《The International journal of biological markers》1998,13(4):224-230
CA 125 is not a specific tumor marker, and is synthesized by normal and malignant cells of different origin (mainly in tissues derived from the müllerian epithelia) in a similar proportion. Abnormal CA 125 levels may be found in fluids of different origin (ascites, pleura, pericardium, amniotic fluid, cyst fluid, bronchoalveolar fluid, etc.) and in serum from patients with these fluids. Differences in serum CA 125 found in malignant or benign diseases may be related to the number of cells that synthesize the marker, and are highly dependent on the access to serum, where the marker is normally determined. Moreover, CA 125 is a very good tumor marker in ovarian and lung cancer. The sensitivity of CA 125 in ovarian cancer is related to stage (40-95%), histological type (lower levels in mucinous adenocarcinoma), and the marker is useful in the early detection of recurrence (sensitivity 80%) and in therapy monitoring. It's sensitivity in lung cancer is lower than in ovarian cancer, 39% in locoregional malignancies and 69% in metastatic disease, but clearly related to stage and histology (mainly in adenocarcinomas and large cell lung cancer) and it is useful in prognosis and disease monitoring. 相似文献
46.
Pea ( Pisum sativum L. cv. Fenomen) and sugar beet ( Beta vulgaris L. cv. Monohill) were cultivated in nutrient media without or with 10 μM CdCl2 . Leaves of the same size and stage of development, detached or still attached to the intact plants, were submerged into redistilled water containing 1 to 250 μM CdCl2 . The uptake experiments were run for 1 to 8 h at pH 3.6 and 5.1. Cuticular transpiration rate, density of leaf and density of stomata were also measured. Percentage of open stomata was studied at different pH.
Foliar uptake of Cd into the leaf is evident since Cd is transported from the exposed part of the pea leaves, through the petioles and into the stipules, and since the Cd concentration of the leaves increases with time and external Cd concentration. The foliar uptake depends on the permeability of the cuticular membrane, which is increased by a high intrinsic Cd level, which in turn enhances the foliar uptake of Cd in sugar beet. Higher cuticular permeability in pea than in sugar beet is shown by a 2.5 times higher cuticular transpiration rate and a 4 times lower density of leaf for pea, which causes a 7 times higher foliar uptake in pea than in sugar beet. Low pH decreases the net uptake of Cd, probably by an exchange reaction in the cutin and pectin of the cuticular membrane. Stomata are not directly involved in the Cd uptake, and the differences in the sum total of stomatal aperture area per unit leaf area is not related to differences in foliar uptake of Cd. Percentage of open stomata, calculated as average of both sides of the leaves, was not affected by changes in pH: but especially at high pH. proportionally more stomata were open on the adaxial than on the abaxial side. 相似文献
Foliar uptake of Cd into the leaf is evident since Cd is transported from the exposed part of the pea leaves, through the petioles and into the stipules, and since the Cd concentration of the leaves increases with time and external Cd concentration. The foliar uptake depends on the permeability of the cuticular membrane, which is increased by a high intrinsic Cd level, which in turn enhances the foliar uptake of Cd in sugar beet. Higher cuticular permeability in pea than in sugar beet is shown by a 2.5 times higher cuticular transpiration rate and a 4 times lower density of leaf for pea, which causes a 7 times higher foliar uptake in pea than in sugar beet. Low pH decreases the net uptake of Cd, probably by an exchange reaction in the cutin and pectin of the cuticular membrane. Stomata are not directly involved in the Cd uptake, and the differences in the sum total of stomatal aperture area per unit leaf area is not related to differences in foliar uptake of Cd. Percentage of open stomata, calculated as average of both sides of the leaves, was not affected by changes in pH: but especially at high pH. proportionally more stomata were open on the adaxial than on the abaxial side. 相似文献
47.
The inhibitory effect of gibberellic acid on flowering in Citrus 总被引:3,自引:1,他引:2
The application of gibberellic acid (GA3 ) at any time from early November until bud sprouting, resulted in a significant inhibition of flowering in the sweet orange [ C. sinensis (L.) Osbeck] and the Satsuma ( C. unshiu Marc.) and Clementine ( C. reticulata Blanco) mandarins. Two response peaks were evident: the first occurred when the application was timed to the translocation of an unknown flowering signal from the leaves to the buds. The second occurred during bud sprouting, at the time the flower primordia were differentiating. From the pattern of flowering, it appears that the mechanism of inhibition was similar irrespective of the timing of GA3 application. There was an initial reduction in bud sprouting affecting selectively those buds originating leafless inflorescences. An additional inhibition resulted in a reduction in the number of leafy inflorescences with an increase in the number of vegetative shoots, suggesting the reversion of a floral to a vegetative apex. The inhibited buds sprouted readily in vitro but invariably vegetative shoots were formed. A continuous influence of the sustaining branch is necessary to keep the flowering commitment of the buds; irreversible commitment occurs when the petal primordia are well differentiated. 相似文献
48.
49.
Studies of basal metabolic rate (BMR), the minimum metabolic rate of postabsorptive, inactive endotherms while in their rest phase and thermal neutral zone, have contributed significantly to our understanding of animal energetics. Besides body mass, the main determinant of BMR, researchers have invoked diet and phylogenetic history as important factors that influence BMR, although their relative importance has been controversial. For 58 species within the Carnivora, we tested the hypothesis that BMR is correlated with home range size, a proxy for level of activity, and diet, using conventional least squares regression (CLSR) and regression based on phylogenetic independent contrasts (PIC). Results showed that BMR of Carnivora was positively correlated with home range size after controlling for body mass, regardless of the statistical method employed. We also found that diet and mass-adjusted home range size were correlated. When we simultaneously tested the effect of diet and mass-adjusted home range on mass-adjusted BMR, home range size was insignificant because of its colinearity with diet. Then we eliminated home range size from our model, and diet proved to be significant with both CLSR and PIC. We concluded that species that eat meat have larger home ranges and higher BMR than species that eat vegetable matter. To advance our understanding of the potential mechanisms that might explain our results, we propose the "muscle performance hypothesis," which suggests that selection for different muscle fiber types can account for the differences in BMR observed between meat eaters and vegetarian species within the Carnivora. 相似文献
50.
Hanaa Shafiek Federico Fiorentino Jose Luis Merino Carla López Antonio Oliver Jaume Segura Ivan de Paul Oriol Sibila Alvar Agustí Borja G Cosío 《PloS one》2015,10(9)