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Cytokine regulation of facilitated glucose transport in human articular chondrocytes. 总被引:10,自引:0,他引:10
A R Shikhman D C Brinson J Valbracht M K Lotz 《Journal of immunology (Baltimore, Md. : 1950)》2001,167(12):7001-7008
Glucose serves as the major energy substrate and the main precursor for the synthesis of glycosaminoglycans in chondrocytes. Facilitated glucose transport represents the first rate-limiting step in glucose metabolism. This study examines molecular regulation of facilitated glucose transport in normal human articular chondrocytes by proinflammatory cytokines. IL-1beta and TNF-alpha, and to a lesser degree IL-6, accelerate facilitated glucose transport as measured by [(3)H]2-deoxyglucose uptake. IL-1beta induces an increased expression of glucose transporter (GLUT) 1 mRNA and protein, and GLUT9 mRNA. GLUT3 and GLUT8 mRNA are constitutively expressed in chondrocytes and are not regulated by IL-1beta. GLUT2 and GLUT4 mRNA are not detected in chondrocytes. IL-1beta stimulates GLUT1 protein glycosylation and plasma membrane incorporation. IL-1beta regulation of glucose transport in chondrocytes depends on protein kinase C and p38 signal transduction pathways, and does not require phosphoinositide 3-kinase, extracellular signal-related kinase, or c-Jun N-terminal kinase activation. IL-1beta-accelerated glucose transport in chondrocytes is not mediated by endogenous NO or eicosanoids. These results demonstrate that stimulation of glucose transport represents a component of the chondrocyte response to IL-1beta. Two classes of GLUTs are identified in chondrocytes, constitutively expressed GLUT3 and GLUT8, and the inducible GLUT1 and GLUT9. 相似文献
997.
Human body odour, symmetry and attractiveness. 总被引:13,自引:0,他引:13
Several studies have found body and facial symmetry as well as attractiveness to be human mate choice criteria. These characteristics are presumed to signal developmental stability. Human body odour has been shown to influence female mate choice depending on the immune system, but the question of whether smell could signal general mate quality, as do other cues, was not addressed in previous studies. We compared ratings of body odour, attractiveness, and measurements of facial and body asymmetry of 16 male and 19 female subjects. Subjects wore a T-shirt for three consecutive nights under controlled conditions. Opposite-sex raters judged the odour of the T-shirts and another group evaluated portraits of the subjects for attractiveness. We measured seven bilateral traits of the subject's body to assess body asymmetry. Facial asymmetry was examined by distance measurements of portrait photographs. The results showed a significant positive correlation between facial attractiveness and sexiness of body odour for female subjects. We found positive relationships between body odour and attractiveness and negative ones between smell and body asymmetry for males only if female odour raters were in the most fertile phase of their menstrual cycle. The outcomes are discussed in the light of different male and female reproductive strategies. 相似文献
998.
Ming Pei You Brandon Lancaster Krishnapillai Sivasithamparam Martin John Barbetti 《Plant and Soil》2008,302(1-2):203-211
In Australia, in the past, pasture legumes were rotated mainly with cereals, but increasingly these rotations now involve
pasture legumes with a wider range of crops, including legumes. This increasing frequency of the leguminous host in the rotation
system may be associated with increased root rots in legumes in the current pasture-crop rotations. The primary aim of this
study was to see whether the pathogenicity on pasture legumes of strains of Rhizoctonia solani sourced from lupins and cereals (common crops in rotation with pastures) is associated with increased incidence of root rots
in pasture legumes in the disease conducive sandy soils of the Mediterranean regions of southern Australia. The second aim
was to determine sources of resistance among newly introduced pasture legumes to R. solani strains originating from rotational crops as this would reduce the impact of disease in the pasture phase. Fifteen pasture
legume genotypes were assessed for their resistance/susceptibility to five different zymogram groups (ZG) of the root rot
pathogen R. solani under glasshouse conditions. Of the R. solani groups tested, ZG1–5 and ZG1–4 (both known to be pathogenic on cereals and legumes) overall, caused the most severe root
disease across the genotypes tested, significantly more than ZG6 (known to be pathogenic on legumes), in turn significantly
>ZG4 (known to be pathogenic on legumes) which in turn was >ZG11 (known to be pathogenic on legumes including tropical species).
Overall, Ornithopus sativus Brot. cvs Cadiz and Margurita, Trifolium michelianum Savi. cvs Paradana and Frontier and T. purpureum Loisel. cv. Electro showed a significant level of resistance to root rot caused by R. solani ZG11 (root disease scores ≤1.2 on a 1–3 scale where 3 = maximum disease severity) while O. sativus cvs Cadiz and Erica showed a significant level of resistance to root rot caused by R. solani ZG4 (scores ≤1.2). O. compressus L. cvs Charano and Frontier, O. sativus cv. Erica, and T. purpureum cv. Electro showed some useful resistance to root rot caused by R. solani ZG6 (scores ≤1.8). This is the first time that cvs Cadiz, Electro, Frontier, Margurita and Paradana have been recognised
for their levels of resistance to root rot caused by R. solani ZG11; and similarly for cvs Cadiz and Erica against ZG4; and for cvs Charano, Erica, and Electro against ZG6. These genotypes
with resistance may also serve as useful sources of resistance in pasture legume breeding programs and also could potentially
be exploited directly into areas where other rotation crops are affected by these R. solani strains. None of the tested genotypes showed useful resistance to R. solani ZG1–4 (scores ≥2.0) or ZG1–5 (scores ≥2.5). This study demonstrates the relative potential of the various R. solani ZG strains, and particularly ZG1–4, ZG1–5, ZG4 and ZG6 to attack legume pastures and pose a significant threat to non-pasture
crop species susceptible to these strains grown in rotation with these pasture legumes. Significantly, the cross-pathogenicity
of these strains could result in the continuous build-up of inoculum of these strains that may seriously affect the productivity
eventually of legumes in all rotations. In particular, when choosing pasture legumes as rotation crops, caution needs to be
exercised so that the cultivars deployed are those with the best resistance to the R. solani ZGs most likely to be prevalent at the location. 相似文献
999.
1000.
F. Hofhansl W. Wanek S. Drage W. Huber A. Weissenhofer A. Richter 《Biogeochemistry》2011,106(3):371-396
Bulk precipitation and throughfall were collected in a wet lowland rainforest in SW Costa Rica on an event basis to allow
modelling the contributions of dry deposition and canopy exchange to nutrient inputs and internal cycling of nutrients. Estimates
based on bulk precipitation underestimated total atmospheric deposition to tropical rainforests by up to 10-fold ignoring
the contributions of dry deposition. Canopy exchange contributed most of the aboveground inputs to the forest soil of Na+, about half for K+, 10% for P and Mg2+ and negligible for N, C and other elements. Tree species composition did not account for the differences found in net throughfall
between forest sites, and vegetation structure (plant area index) had only a small effect on net throughfall. Forest regrowth
affected net throughfall through reduced soil fertility and differences in leaf traits. Topography most significantly affected
net throughfall via increased dry deposition at sites of higher elevation and via soil fertility and increased canopy exchange
at down slope sites. 相似文献