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1.
Numerous clinical and epidemiological studies link enteroviruses such as the Coxsackie virus group with the autoimmune disease type 1 diabetes mellitus (DM). In addition, there are reports that patients with type 1 DM are characterized by skewing of TCR Vbeta chain selection among peripheral blood and intraislet T lymphocytes. To examine these issues, we analyzed TCR Vbeta chain-specific up-regulation of the early T cell activation marker, CD69, on CD4 T cells after incubation with Coxsackievirus B4 (CVB4) Ags. CD4 T cells bearing the Vbeta chains 2, 7, and 8 were the most frequently activated by CVB4. Up-regulation of CD69 by different TCR families was significantly more frequent in new onset type 1 DM patients (p = 0.04), 100% of whom (n = 8) showed activation of CD4 T cells bearing Vbeta8, compared with 50% of control subjects (n = 8; p = 0.04). T cell proliferation after incubation with CVB4 Ags required live, nonfixed APCs, suggesting that the selective expansion of CD4 T cells with particular Vbeta chains resulted from conventional antigen processing and presentation rather than superantigen activity. Heteroduplex analysis of TCR Vbeta chain usage after CVB4 stimulation indicated a relatively polyclonal, rather than oligo- or monoclonal response to viral Ags. These results provide evidence that new-onset patients with type 1 DM and healthy controls are primed against CVB4, and that CD4 T cell responses to the virus have a selective TCR Vbeta chain usage which is driven by viral Ags rather than a superantigen.  相似文献   
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Neuropeptide Y (NPY) is an evolutionarily conserved neurosecretory molecule implicated in a diverse complement of functions across taxa and in regulating feeding behavior and reproductive maturation in Octopus. However, little is known about the precise molecular circuitry of NPY-mediated behaviors and physiological processes, which likely involve a complex interaction of multiple signal molecules in specific brain regions. Here, we examined the expression of NPY throughout the Octopus central nervous system. The sequence analysis of Octopus NPY precursor confirmed the presence of both, signal peptide and putative active peptides, which are highly conserved across bilaterians. In situ hybridization revealed distinct expression of NPY in specialized compartments, including potential “integration centers,” where visual, tactile, and other behavioral circuitries converge. These centers integrating separate circuits may maintain and modulate learning and memory or other behaviors not yet attributed to NPY-dependent modulation in Octopus. Extrasomatic localization of NPY mRNA in the neurites of specific neuron populations in the brain suggests a potential demand for immediate translation at synapses and a crucial temporal role for NPY in these cell populations. We also documented the presence of NPY mRNA in a small cell population in the olfactory lobe, which is a component of the Octopus feeding and reproductive control centers. However, the molecular mapping of NPY expression only partially overlapped with that produced by immunohistochemistry in previous studies. Our study provides a precise molecular map of NPY mRNA expression that can be used to design and test future hypotheses about molecular signaling in various Octopus behaviors.  相似文献   
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In the fruitfly, Drosophila melanogaster, autophagy and caspase activity function in parallel in the salivary gland during metamorphosis and in a common regulatory hierarchy during oogenesis. Both autophagy and caspase activity progressively increase in the remodeling fat body, and they are induced by a pulse of the molting hormone (20-hydroxyecdysone, 20E) during the larval-prepupal transition. Inhibition of autophagy and/or caspase activity in the remodeling fat body results in 25–40% pupal lethality, depending on the genotypes. Interestingly, a balancing crosstalk occurs between autophagy and caspase activity in this tissue: the inhibition of autophagy induces caspase activity and the inhibition of caspases induces autophagy. The Drosophila remodeling fat body provides an in vivo model for understanding the molecular mechanism of the balancing crosstalk between autophagy and caspase activity, which oppose with each other and are induced by the common stimulus 20E, and blockage of either path reinforces the other path.  相似文献   
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A cDNA probe of the human COL5A1 gene detects a frequent biallelic PstI polymorphism. Allele A has a frequency of 54% whereas that of allele B is 46%. This restriction fragment length polymorphism provides a useful marker for linkage analysis in 9q34.3.  相似文献   
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Monitoring ecosystem functions in forests is a priority in a climate change scenario, as climate‐induced events may initially alter the functions more than slow‐changing attributes, such as biomass. The ecosystem functional properties (EFPs) are quantities that characterize key ecosystem processes. They can be derived by point observations of gas and energy exchanges between the ecosystems and the atmosphere that are collected globally at FLUXNET flux tower sites and upscaled at ecosystem level. The properties here considered describe the ability of ecosystems to optimize the use of resources for carbon uptake. They represent functional forest information, are dependent on environmental drivers, linked to leaf traits and forest structure, and influenced by climate change effects. The ability of vegetation optical depth (VOD) to provide forest functional information is investigated using 2011–2014 satellite data collected by the Soil Moisture and Ocean Salinity mission and using the EFPs as reference dataset. Tropical forests in Africa and South America were analyzed, also according to ecological homogeneous units. VOD jointly with water deficit information explained 93% and 87% of the yearly variability in both flux upscaled maximum gross primary productivity and light use efficiency functional properties, in Africa and South America forests respectively. Maps of the retrieved properties evidenced changes in forest functional responses linked to anomalous climate‐induced events during the study period. The findings indicate that VOD can support the flux upscaling process in the tropical range, affected by high uncertainty, and the detection of forest anomalous functional responses. Preliminary temporal analysis of VOD and EFP signals showed fine‐grained variability in periodicity, in signal dephasing, and in the strength of the relationships. In selected drier forest types, these satellite data could also support the monitoring of functional dynamics.  相似文献   
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Molecular Biology Reports - Benign metastasizing leiomyoma (BML) is a rare disease characterized by extrauterine benign leiomyomatosis in patients with a previous or concomitant history of uterine...  相似文献   
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This study modelled the probability of introduction of Hyalomma marginatum into Europe by predicting the potential migratory routes of 28 bird species and the probability to carry immatures of the tick. Flyways were modelled as a spatio-temporal feature, at weekly intervals, using satellite-derived data of temperature and vegetal phenology, together with cost surfaces derived from speed and direction of the wind (years 2002–2018). The expected period of activity of tick immatures defined the probability of ticks being carried by birds along the modelled flyways. The probability of moulting of the engorged nymphs was modelled as a linear relationship of the daily sum of temperatures after tick introduction by birds. Positive probabilities of tick introduction extend the known northern range of permanent populations to central and western France, and large portions of central Europe. The flight of birds into an area and thence the risk of introduction of H. marginatum is very heterogeneous, with sites receiving “waves” of different bird species at diverse times of the year. Therefore, there is not a clear period of time for introduction, as it depends on the modelled behaviour of the bird species. The probability of introduction into Baltic and Nordic countries is small. We hypothesise that conditions of a warmer climate might support permanent populations of H. marginatum if a high number of immatures is introduced. Active surveys in risky territories, where the tick is not yet established, are advisable for rapid intervention.  相似文献   
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