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51.
Exercising or working in a hot, humid environment can results in the onset of heat-related illness when an individual''s temperature is not carefully monitored. The purpose of the present study was to compare three techniques (data loggers, thermal imaging, and wired electrodes) for the measurement of peripheral (bicep) and central (abdominal) skin temperature. Young men and women (N = 30) were recruited to complete the present study. The three skin temperature measurements were made at 0 and every 10-min during 40-min (60% VO2max) of cycling in a hot (39±2°C), humid (45±5% RH) environment. Data was statistically analyzed using the Bland-Altman method and correlation analysis. For abdominal skin temperature, the Bland-Altman limits of agreement indicated that data loggers (1.5) were a better index of wired than was thermal imaging (3.5), For the bicep skin temperature the limits of agreement was similar between data loggers (1.9) and thermal (1.9), suggesting the both were suitable measurements. We also found that when skin temperature exceeded 35°C, we observed progressively better prediction between data loggers, thermal imaging, and wired skin sensors. This report describes the potential for the use of data loggers and thermal imaging to be used as alternative measures of skin temperature in exercising, human subjects.  相似文献   
52.
Human Vγ9Vδ2 T cells are a unique T-cell type, and data from recent studies of Vγ9Vδ2 T cells emphasize their potential relevance to cancer immunotherapy. Vγ9Vδ2 T cells exhibit dual properties since they are both antigen-presenting cells and cytotoxic toward cancer cells. The majority of Vγ9Vδ2 T cells are double-negative for the co-receptors CD4 and CD8, and only 20–30% express CD8. Even though they are mostly neglected, a small fraction of Vγ9Vδ2 T cells also express the co-receptor CD4. Here the authors show that CD4+ Vγ9Vδ2 T cells comprise 0.1–7% of peripheral blood Vγ9Vδ2 T cells. These cells can be expanded in vitro using zoledronic acid, pamidronic acid or CD3 antibodies combined with IL-2 and feeder cells. Unlike most conventional CD4+ αβ T cells, CD4+ Vγ9Vδ2 T cells are potently cytotoxic and can kill cancer cells, which is here shown by the killing of cancer cell lines of different histological origins, including breast cancer, prostate cancer and melanoma cell lines, upon treatment with zoledronic acid. Notably, the killing capacity of CD4+ Vγ9Vδ2 T cells correlates with co-expression of CD56.  相似文献   
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Changes in rainfall availability will alter soil‐nutrient availability under a climate‐change scenario. However, studies have usually analyzed the effect of either drier or wetter soil conditions, despite the fact that both possibilities will coexist in many climatic regions of the world. Furthermore, its effect may vary across the different habitats of the ecosystem. We experimentally investigated the effect of three contrasting climatic scenarios on different carbon (C), nitrogen (N), and phosphorus (P) fractions in soil and microbial compartments among three characteristic habitats in a Mediterranean‐type ecosystem: forest, shrubland, and open areas. The climatic scenarios were dry summers, according to the 30% summer rainfall reduction projected in the Mediterranean; wet summer, simulating summer storms to reach the maximum historical records in the study area; and current climatic conditions (control). Sampling was replicated during two seasons (spring and summer) and 2 years. The climatic scenario did not affect the nutrient content in the litter layer. However, soil and microbial nutrients varied among seasons, habitats, and climatic scenarios. Soil‐nutrient fractions increased with lower soil‐moisture conditions (dry scenario and summer), whereas microbial nutrients increased under the wet summer scenario and spring. This pattern was consistent both studied years, although it was modulated by habitat, differences being lower with denser plant cover. Holm oak seedlings, used as live control of the experiment, tended to increase their N and P content (although not significantly) with water availability. Thus, the results support the idea that higher rainfall boosts microbial and plant‐nutrient uptake, and hence nutrient cycling. By contrast, a rainfall reduction leads to an accumulation of nutrients in the soil, increasing the risk of nutrient loss by leaching or erosion. These results show that the projected climate change will have significant effects on nutrient cycles, and therefore will have important implications on the ecosystem functioning.  相似文献   
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With the aim to identify cyclin B1-derived peptides with high affinity for HLA-A2, we used three in silico prediction algorithms to screen the protein sequence for possible HLA-A2 binders. One peptide scored highest in all three algorithms, and the high HLA-A2-binding affinity of this peptide was verified in an HLA stabilization assay. By stimulation with peptide-loaded dendritic cells a CTL clone was established, which was able to kill two breast cancer cell lines in an HLA-A2-dependent and peptide-specific manner, demonstrating presentation of the peptide on the surface of cancer cells. Furthermore, blood from cancer patients and healthy donors was screened for spontaneous T-cell reactivity against the peptide in IFN-γ ELISPOT assays. Patients with breast cancer, malignant melanoma, or renal cell carcinoma hosted powerful and high-frequency T-cell responses against the peptide. In addition, when blood from healthy donors was tested, similar responses were observed. Ultimately, serum from cancer patients and healthy donors was analyzed for anti-cyclin B1 antibodies. Humoral responses against cyclin B1 were frequently detected in both cancer patients and healthy donors. In conclusion, a high-affinity cyclin B1-derived HLA-A2-restricted CTL epitope was identified, which was presented on the cell surface of cancer cells, and elicited spontaneous T-cell responses in cancer patients and healthy donors.  相似文献   
57.
Survival typically contributes most to population trends in long‐lived birds and its accurate estimation is therefore vital for population management and conservation. We evaluated the effects of age, territoriality and reproduction on survival in Bonelli’s Eagle Aquila fasciata through multistate capture‐mark‐recapture analyses on a long‐term dataset. Monitoring was carried out in southeast France (1990–2008) and involved the surveying of territorial Eagles, the marking of fledged chicks, and the recording of resightings and recoveries of marked non‐territorial and territorial birds. Survival improved with age, but territoriality was not retained in the best model; yearly survival was estimated at 0.479 for fledglings (to 1 year of age), 0.570 for 1‐ and 2‐year‐olds, and 0.870 for 3‐year‐old and older individuals. The second best model supported a further increase in survival from 3‐year‐olds (0.821) to older individuals (0.880). In the third best supported model, territoriality enhanced survival, but only in 2‐year‐olds (0.632 vs. 0.562 for non‐territorial). We found no correlation between the previous breeding stage and future survival, consistent with the long lifespan of the study species. Nevertheless, 4‐year‐old and older successful breeders were more likely to breed the following year than failed adult breeders (0.869 vs. 0.582), suggesting that the cost of reproduction is small in comparison with the variation in quality among individuals or their territories.  相似文献   
58.
The folding and stabilization of α-helical transmembrane proteins are still not well understood. Following cofactor binding to a membrane protein provides a convenient method to monitor the formation of appropriate native structures. We have analyzed the assembly and stability of the transmembrane cytochrome b559′, which can be efficiently assembled in vitro from a heme-binding PsbF homo-dimer by combining free heme with the apo-cytochrome b559′. Unfolding of the protein dissolved in the mild detergent dodecyl maltoside may be induced by addition of SDS, which at high concentrations leads to dimer dissociation. Surprisingly, absorption spectroscopy reveals that heme binding and cytochrome formation at pH 8.0 are optimal at intermediate SDS concentrations. Stopped-flow kinetics revealed that genuine conformational changes are involved in heme binding at these SDS concentrations. GPS (Global Protein folding State mapping) NMR measurements showed that optimal heme binding is intimately related to a change in the degree of histidine protonation. In the absence of SDS, the pH curve for heme binding is bell-shaped with an optimum at around pH 6-7. At alkaline pH values, the negative electrostatic potential of SDS lowers the local pH sufficiently to restore efficient heme binding, provided the amount of SDS needed for this does not denature the protein. Accordingly, the higher the pH value above 6-7, the more SDS is needed to improve heme binding, and this competes with the inherent tendency of SDS to dissociate cytochrome b559′. Our work highlights that, in addition to its denaturing properties, SDS can affect protein functions by lowering the local pH.  相似文献   
59.
Abstract: The Jurassic was an important period in the evolution of Testudinata and encompasses the origin of many clades, and this is especially true of Jurassic turtles from Western Europe. A new genus and species of Late Jurassic turtle, Hispaniachelys prebetica gen. et sp. nov. from the upper Oxfordian of the Prebetic (Southern Spain), is described on the basis of postcranial material. The specimen is the only known tetrapod from the Mesozoic of the Prebetic and the oldest turtle from southern Europe. A mosaic of characters indicates this is a new genus: it displays basal features including dorsal epiplastral processes/reduced cleithra, no medial contact of the extragulars and a long first thoracic rib, alongside derived characters including an absence of mesoplastra and the vertebral 3/4 sulcus crossing neural 5. The phylogenetic position of the new taxon is hard to resolve, and it might be either a paracryptodire or a basal testudine, but it is distinct from Plesiochelys. A complex taphonomic history is shown by a range of overlying grazing traces and bioerosion on the carapace. The carapace was subsequently overturned and buried ventrally up, terminating grazing activity, and was then bored by sponges before final burial. Scanning electron microscopy reveals phosphatic microspheroids associated with bacterial decay in the vascular cavities of the cancellous bone, suggesting the carapace may have acted as a closed microenvironment in which decay‐derived authigenic minerals formed.  相似文献   
60.
Based on the detection of spontaneous immune responses in cancer patients with cancer of different origin, Bcl-X(L) was recently described as a highly interesting tumor antigen recognized by CD8 positive cytotoxic T lymphocytes. To further characterize Bcl-X(L) as a tumor antigen we isolated and expanded Bcl-X(L) specific T cells from the peripheral blood of a breast cancer patient hosting a strong Bcl-X(L) specific T cell response. We describe that HLA-A2 restricted Bcl-X(L) specific T cell clones very efficiently lyse peptide pulsed T2 cells. Furthermore, tumor cell lines of different origin, i.e., breast cancer, colon cancer, and melanoma, are efficiently lysed in an HLA-dependent manner. Finally, ex vivo-isolated leukemia cells, but not non-malignant B and T cells are killed by Bcl-X(L) specific T cells. Our data underline Bcl-X(L) as an universal tumor antigen widely applicable in specific anticancer immunotherapy.  相似文献   
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