844 resultados para Human figure in art


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Background: Receptor Activator of Nuclear Factor kappaB Ligand (RANKL), a member of the TNF superfamily, contributes to the imbalance of bone resorption and immunoregulation in rheumatoid arthritis. In mice, collagen induced arthritis was exacerbated by IL-3 and anti-IgER antibodies, two mediators activating basophils that are known as effector cells of allergy. Interestingly, our unpublished microarray data revealed that IL-3 induces RANKL mRNA in human basophils. Here we further investigate under which conditions human basophils express surface and/or soluble RANKL. Methods: One part of purified human basophils was co-stimulated with IL-3 and either IgE-dependent or IgE-independent stimuli. The other part of purified basophils was first primed with IL-3 and subsequently triggered with IgE-dependent or IgE-independent stimuli. Expression of surface and soluble RANKL were detected by flow cytometry, ELISA and real-time PCR. Results: By flow cytometry we show that IL-3 induces de novo expression of surface RANKL on human basophils in a time and dose dependent manner. Co-stimulation of basophils with IL-3 and an IgE-dependent stimulus reduces IL-3-induced expression of surface RANKL in a dose dependent manner while IgE-independent stimuli have no effect. In contrast, both IgE-dependent and IgE-independent stimuli enhance expression of surface and soluble RANKL in basophils that were first primed with IL-3 and then triggered. Real-time PCR analysis shows that surface hRANKL1 and soluble hRANKL3 are induced by IL-3 and reduced by co-stimulation with IL-3 and an IgE-dependent stimulus and thus confirms our flow cytometry data. Conclusion: RANKL expression in human basophils is not only dependent on IL-3 and IgE-dependent/IgE-independent stimuli but also on the sequence of their addition to cell culture. Based on our data, we suggest that basophils might have previously unidentified functions in bone resorption or immunoregulation via RANKL.

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Heparanase, an endo-$\beta$-D-glucuronidase, has been associated with melanoma metastasis. Polyclonal antibodies directed against the murine N-terminal heparanase peptide detected a M$\sb{\rm r}\sim 97,000$ protein upon SDS-polyacrylamide gel electrophoresis of mouse melanoma and human melanoma cell lysates. In an indirect immunocytochemical study, metastatic human A375-SM and mouse B16-BL6 melanoma cells were stained with the anti-heparanase antibodies. Heparanase antigen was localized in the cytoplasm of permeabilized melanoma cells as well as at the cell surface of unpermeabilized cells. Immunohistochemical staining of frozen sections from syngeneic mouse organs containing micrometastases of B16-BL6 melanoma demonstrated heparanase localized in metastatic melanoma cells, but not in adjacent normal tissues. Similar studies using frozen sections of malignant melanomas resected from patients indicated that heparanase is localized in invading melanoma cells, but not in adjacent connective tissues.^ Monoclonal antibodies directed against murine heparanase were developed and characterized. Monoclonal antibody 10E5, an IgM, precipitated and inhibitated the enzymatic activity of heparanase. A 2.6 kb cDNA was isolated from a human melanoma $\lambda$gt11 cDNA library using the monoclonal antibody 10E5. Heparan sulfate cleavage activity was detected in the lysogen lysates from E. Coli Y1089 infected with the $\lambda$gt11 cDNA and this activity was inhibited in the presence of 10-fold excess of heparin, a potent inhibitor of heparanase. The nucleotide sequence of the cDNA was determined and insignificant homology was found with the gene sequences currently known. The cDNA hybridized to a 3.2-3.4 kb mRNA in human A375 melanoma, WI-38 fibroblast, and THP-1 leukemia cells using Northern blots.^ Heparanase expression was examined using Western and Northern blots. In comparison to human A375-P melanoma cells, the quantity of 97,000 protein recognized by the polyclonal anti-heparanase antibodies doubled in the metastatic variant A375-SM cells and the quantity of 3.2-3.4 kb mRNA doubled in A375MetMix, a metastatic variant similar to A375-SM cells. In B16 murine melanoma cell, the intensity of the 97,000 protein increased more than 2 times comparing with B16-F1 cells. The extent in the increase of the protein and the mRNA levels is comparable to the change of heparanase activity observed in those cells.^ In summary, the studies suggest that (a) the N-terminus of the heparanase molecule in mouse and human is antigenically related; (b) heparanase antigens are localized at the cell surface and in the cytoplasm of metastatic human and mouse melanoma cells; (c) heparanase antigens are localized in invasive and metastatic murine and human melanomas in vivo, but not in adjacent normal tissues; (d) heparanase molecule appeared to be differentially expressed at the transcriptional as well as at the translational level; and (e) the size of human heparanase mRNA is 3.2-3.4 kilobase. ^

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Fusion of nonmetastatic murine melanoma K1735 C19H cells with metastatic human melanoma A375 C15N cells resulted in a hybrid (termed H7) which was highly metastatic in a nude mouse model. The H7 hybrid retained chromosome 17 as the sole intact human chromosome in the cell. A lung bioassay showed that the K1735 C19H cells were present in the lungs of nude mice with s.c. tumors, yet at 6-weeks after tumor resection, no cells remained in the lung and therefore did not form lung metastases. Examination of various phenotypic properties such as in vivo and in vitro growth demonstrated that phenotypically the H7 hybrid was most like the K1735 C19H cell line except for its metastatic ability. In contrast the H7 hybrid cells containing single or multiple copies of human chromosome 17 with a point mutation at codon 249 (arg-gly) of the p53 gene, readily formed lung metastases. A plasmid containing the human p53 from the H7 hybrid and four other contructs with mutations at codon 143 (val-arg), 175 (arg-his), 249 (arg-ser) and 273 (arg-his) were transfected into K1735 C19H cells. K1735 C19H cells expressing human p53 genes with mutations at codons 249, both the arg-ser mutation and the mutation from the H7 hybrid and 273 produced significantly more lung metastases.^ In vitro assays demonstrated that responses to various cytotoxic and DNA damaging agents varied with the presence of mutant p53 and with the type of agent used. When cultured in mouse lung-conditioned medium, the K1735 C19H cell line was growth-inhibited, while cells containing a mutant human p53 (either on the whole chromosome 17, as in the H7 hybrid cells or from a stably transfected construct) were growth stimulated. Western blot analysis of lung-conditioned media derived from either 6-month or 15-month old mice has detected high levels of soluble Fas ligand in the medium from older animals. Comparison of the levels of Fas receptor on the K1735 C19H cell line and the H7 hybrid were almost identical, but 50% of the K1735 C19H cells were killed in the presence of anti-Fas antibody as opposed to 7% of the H7 hybrid cells. The growth-inhibitory effects of the lung-conditioned medium on the K1735 C19H cells were abrogated by coculture with Fas-Fc, which competes with the Fas ligand for receptor binding. Growth-inhibition of the K1735 C19H was 54% when cultured in 60 $\mu$g/0.2 ml lung-conditioned medium and a control Fc, with only 9% inhibition in 60 $\mu$g/0.2 ml lung-conditioned medium and Fas-Fc. Growth of the H7 cells and K1735 C19H cells transfected with various mutant human p53 genes were unchanged by the presence of either the control Fc or the Fas-Fc. This indicates that the presence of human chromosome 17, and mutant p53 in part protects the cells from Fas:Fas ligand induced apoptosis, and allows the growth of lung metastases. ^

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Rapid industrialization and urbanization in developing countries has led to an increase in air pollution, along a similar trajectory to that previously experienced by the developed nations. In China, particulate pollution is a serious environmental problem that is influencing air quality, regional and global climates, and human health. In response to the extremely severe and persistent haze pollution experienced by about 800 million people during the first quarter of 2013 (refs 4, 5), the Chinese State Council announced its aim to reduce concentrations of PM2.5 (particulate matter with an aerodynamic diameter less than 2.5micrometres) by up to 25 per cent relative to 2012 levels by 2017 (ref. 6). Such efforts however require elucidation of the factors governing the abundance and composition of PM2.5, which remain poorly constrained in China. Here we combine a comprehensive set of novel and state-of-the-art offline analytical approaches and statistical techniques to investigate the chemical nature and sources of particulate matter at urban locations in Beijing, Shanghai, Guangzhou and Xi'an during January 2013. We find that the severe haze pollution event was driven to a large extent by secondary aerosol formation, which contributed 30-77 per cent and 44-71 per cent (average for all four cities) of PM2.5 and of organic aerosol, respectively. On average, the contribution of secondary organic aerosol (SOA) and secondary inorganic aerosol (SIA) are found to be of similar importance (SOA/SIA ratios range from 0.6 to 1.4). Our results suggest that, in addition to mitigating primary particulate emissions, reducing the emissions of secondary aerosol precursors from, for example, fossil fuel combustion and biomass burning is likely to be important for controlling China's PM2.5 levels and for reducing the environmental, economic and health impacts resulting from particulate pollution.

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AIM The autonomic innervation of the heart consists of sympathetic and parasympathetic nerve fibres, and fibres of the intrinsic ganglionated plexus with noradrenaline and acytylcholine as principal neurotransmitters. The fibres co-release neuropeptides to modulate intracardiac neurotransmission by specific presynaptic and postsynaptic receptors. The coexpression of angiotensin II in sympathetic fibres of the human heart and its role are not known so far. METHODS Autopsy specimens of human hearts were studied (n=3; ventricles). Using immunocytological methods, cryostat sections were stained by a murine monoclonal antibody (4B3) directed against angiotensin II and co-stained by polyclonal antibodies against tyrosine hydroxylase, a catecholaminergic marker. Visualisation of the antibodies was by confocal light microscopy or laser scanning microscopy. RESULTS Angiotensin II-positive autonomic fibres with and without a catecholaminergic cophenotype (hydroxylase-positive) were found in all parts of the human ventricles. In the epicardium, the fibres were grouped in larger bundles of up to 100 and more fibres. They followed the preformed anatomic septa and epicardial vessels towards the myocardium and endocardium where the bundles dissolved and the individual fibres spread between myocytes and within the endocardium. Generally, angiotensinergic fibres showed no synaptic enlargements or only a few if they were also catecholaminergic. The exclusively catechalominergic fibres were characterised by multiple beaded synapses. CONCLUSION The autonomic innervation of the human heart contains angiotensinergic fibres with a sympathetic efferent phenotype and exclusively angiotensinergic fibers representing probably afferents. Angiotensinergic neurotransmission may modulate intracardiac sympathetic and parasympathetic activity and thereby influence cardiac and circulatory function.

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DNA sequence variation is currently a major source of data for studying human origins, evolution, and demographic history, and for detecting linkage association of complex diseases. In this dissertation, I investigated DNA variation in worldwide populations from two ∼10 kb autosomal regions on 22q11.2 (noncoding) and 1q24 (introns). A total of 75 variant sites were found among 128 human sequences in the 22q11.2 region, yielding an estimate of 0.088% for nucleotide diversity (π), and a total of 52 variant sites were found among 122 human sequences in the 1q24 region with an estimated π value of 0.057%. The data from these two regions and a 10 kb noncoding region on Xq13.3 all show a strong excess of low-frequency variants in comparison to that expected from an equilibrium population, indicating a relatively recent population expansion. The effective population sizes estimated from the three regions were 11,000, 12,700, and 8,600, respectively, which are close to the commonly used value of 10,000. In each of the two autosomal regions, the age of the most recent common ancestor (MRCA) was estimated to be older than 1 million years among all the sequences and ∼600,000 years among non-African sequences, providing first evidence from autosomal noncoding or intronic regions for a genetic history of humans much more ancient than the emergence of modern humans. The ancient genetic history of humans indicates no severe bottleneck during the evolution of humans in the last half million years; otherwise, much of the ancient genetic history would have been lost during a severe bottleneck. This study strongly suggests that both the “out of Africa” and the multiregional models are too simple for explaining the evolution of modern humans. A compilation of genome-wide data revealed that nucleotide diversity is highest in autosomal regions, intermediate in X-linked regions, and lowest in Y-linked regions. The data suggest the existence of background selection or selective sweep on Y-linked loci. In general, the nucleotide diversity in humans is low compared to that in chimpanzee and Drosophila populations. ^

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Our paper asks the question: Does mode of instruction format (live or online format) effect test scores in the principles of macroeconomics classes? Our data are from several sections of principles of macroeconomics, some in live format, some in online format, and all taught by the same instructor. We find that test scores for the online format, when corrected for sample selection bias, are four points higher than for the live format, and the difference is statistically significant. One possible explanation for this is that there was slightly higher human capital in the classes that had the online format. A Oaxaca decomposition of this difference in grades was conducted to see how much was due to human capital and how much was due to the differences in the rates of return to human capital. This analysis reveals that 25% of the difference was due to the higher human capital with the remaining 75% due to differences in the returns to human capital. It is possible that for the relatively older student with the appropriate online learning skill set, and with schedule constrains created by family and job, the online format provides them with a more productive learning environment than does the alternative traditional live class format. Also, because our data are limited to the student s academic transcript, we recommend future research include data on learning style characteristics, and the constraints formed by family and job choices.

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Chagas’ disease, also called American Trypanosomiasis, is a vector-borne disease caused by the protozoan parasite Trypanosoma cruzi. T. cruzi is spread by triatomine insects, commonly referred to as ‘kissing bugs.’ After the insect takes a blood meal from its animal or human host, it usually defecates near the bite wound. The parasite is present in the feces, and when rubbed into the bite wound or mucous membranes by the host, infection ensues. Chagas’ disease is highly endemic in Central and South America where it originated. Many people in these endemic areas live in poor conditions surrounded by animals, mainly dogs, that can serve as a possible link to human infection. In Chagas’ endemic countries, dogs can be used as a sentinel to infer risk for human infection. In Texas, the prevalence of Chagas’ and risk for human infection is largely unknown. This study aimed to determine the prevalence of Chagas’ disease in shelter dogs in Houston, Texas and the Rio Grande Valley region by using an immunochromatographic assay (Chagas’ Stat-Pak) to test for the presence of T. cruzi antibodies. Of the 822 samples tested, 26 were found to be positive (3.2%). In both locations, Chagas’ prevalence increased over time. This study found that dogs, especially strays, can serve as sentinels for disease activity. Public health authorities can implement this strategy to understand the level of Chagas’ activity in a defined geographic area and prevent human infection.^

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Se presentan el informe nacional de Brazil, la recopilación de información de Naciones Unidas y el resumen de información realizadas por el Consejo de Derechos Humanos, Grupo de Trabajo sobre el Examen Periódico Universal en el marco de la Asamblea General de las Naciones Unidas realizadas del 21 de Mayo al 4 de Junio del 2012 en Ginebra. Se destacan las preocupaciones expresadas por la Comisión de Ciudadanía y Reproducción (CCR) por las cuáles recomienda la difusión de evidencia científica que apoya el uso de misoprostol, así como las instrucciones correctas para su uso en el contexto de la divulgación de la salud sexual y reproductiva.

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Carbon management has gradually gained attention within the overall environmental management and corporate social responsibility agendas. The clean development mechanism, from Kyoto Protocol, was envisioned as connecting carbon market and sustainable development objectives in developing countries. Previous research has shown that this potential is rarely being achieved. The paper explores how the incorporation of the human side into carbon management reinforces its contribution to generate human development in local communities and to improve the company's image. A case study of a Brazilian company is presented, with the results of the application of an analytical model that incorporates the human side and human development. The selected project is an "efficient stoves" programme. "Efficient stoves" are recognised in Brazil as social technologies. Results suggest that the fact that social technologies value the human side of the technology plays a key role when it comes to analysing the co-benefits of the project implementation.