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351.
Goretti Enzo Ceccagnoli Donatella La Porta Gianandrea Di Giovanni Maria Vittoria 《Hydrobiologia》2001,457(1-3):149-154
A three-year investigation was carried out on the life cycle of Aeshna cyanea (Müller, 1764) (Odonata, Aeshnidae) in temporary freshwater pools in Central Italy. The instars were discriminated by size and scatter plot, based on measurements of labium length, head width, metafemur length, forewing-pad length and total larval body length. The prolarvae instar was derived by Dyar's law. The mean increase value index between following and previous instar was between 1.26 and 1.33 for isometric variables, and around 1.96 for the wing-pad allometric variable. A. cyanea entered diapause mainly at the F-2 instar, placing it almost intermediate between the Southern Spain populations, which usually overwintered in the F-3 instar, and those of England and Central Europe, who spent their last winter in F-1. A. cyanea appeared to be a `summer species', as defined by Corbet (1962), and the population we studied had a semivoltine life cycle. 相似文献
352.
The presence of CCK-containing neuroendocrine cells in human adenomatous prostates, and the colocalization of CCK together with serotonin in the same cell, have been demonstrated by means of an immunohistochemical technique and by a double labeling immunofluorescent staining. CCK-containing neuroendocrine cells had a focal distribution in the prostates and sometimes showed dendrite-like cytoplasmic processes. The major part of CCK (96.55%) colocalized with serotonin.CCK probably stimulates muscle contraction and endocrine/exocrine secretions in the urogenital tract. 相似文献
353.
Raffaele Iennaco Giulio Formenti Camilla Trovesi Riccardo Lorenzo Rossi Chiara Zuccato Tiziana Lischetti Vittoria Dickinson Bocchi Andrea Scolz Cristina Martínez-Labarga Olga Rickards Michela Pacifico Angelica Crottini Anders Pape Mller Richard Zhenghuan Chen Thomas Francis Vogt Giulio Pavesi David Stephen Horner Nicola Saino Elena Cattaneo 《Cell death and differentiation》2022,29(2):293
354.
Molecular Control of Flowering in Response to Day Length in Rice 总被引:1,自引:0,他引:1
355.
After the emergence of the H1N1 influenza in 2009, some countries responded with travel-related controls during the early stage of the outbreak in an attempt to contain or slow down its international spread. These controls along with self-imposed travel limitations contributed to a decline of about 40% in international air traffic to/from Mexico following the international alert. However, no containment was achieved by such restrictions and the virus was able to reach pandemic proportions in a short time. When gauging the value and efficacy of mobility and travel restrictions it is crucial to rely on epidemic models that integrate the wide range of features characterizing human mobility and the many options available to public health organizations for responding to a pandemic. Here we present a comprehensive computational and theoretical study of the role of travel restrictions in halting and delaying pandemics by using a model that explicitly integrates air travel and short-range mobility data with high-resolution demographic data across the world and that is validated by the accumulation of data from the 2009 H1N1 pandemic. We explore alternative scenarios for the 2009 H1N1 pandemic by assessing the potential impact of mobility restrictions that vary with respect to their magnitude and their position in the pandemic timeline. We provide a quantitative discussion of the delay obtained by different mobility restrictions and the likelihood of containing outbreaks of infectious diseases at their source, confirming the limited value and feasibility of international travel restrictions. These results are rationalized in the theoretical framework characterizing the invasion dynamics of the epidemics at the metapopulation level. 相似文献
356.
Barone MV Zanzi D Maglio M Nanayakkara M Santagata S Lania G Miele E Ribecco MT Maurano F Auricchio R Gianfrani C Ferrini S Troncone R Auricchio S 《PloS one》2011,6(2):e17039
Background and Objectives
Damage to intestinal mucosa in celiac disease (CD) is mediated both by inflammation due to adaptive and innate immune responses, with IL-15 as a major mediator of the innate immune response, and by proliferation of crypt enterocytes as an early alteration of CD mucosa causing crypts hyperplasia. We have previously shown that gliadin peptide P31-43 induces proliferation of cell lines and celiac enterocytes by delaying degradation of the active epidermal growth factor receptor (EGFR) due to delayed maturation of endocytic vesicles. IL-15 is increased in the intestine of patients affected by CD and has pleiotropic activity that ultimately results in immunoregulatory cross-talk between cells belonging to the innate and adaptive branches of the immune response. Aims of this study were to investigate the role of P31-43 in the induction of cellular proliferation and innate immune activation.Methods/Principal Findings
Cell proliferation was evaluated by bromodeoxyuridine (BrdU) incorporation both in CaCo-2 cells and in biopsies from active CD cases and controls. We used real-time PCR to evaluate IL-15 mRNA levels and FACS as well as ELISA and Western Blot (WB) analysis to measure protein levels and distribution in CaCo-2 cells.Gliadin and P31-43 induce a proliferation of both CaCo-2 cells and CD crypt enterocytes that is dependent on both EGFR and IL-15 activity. In CaCo-2 cells, P31-43 increased IL-15 levels on the cell surface by altering intracellular trafficking. The increased IL-15 protein was bound to IL15 receptor (IL-15R) alpha, did not require new protein synthesis and functioned as a growth factor.Conclusion
In this study, we have shown that P31-43 induces both increase of the trans-presented IL-15/IL5R alpha complex on cell surfaces by altering the trafficking of the vesicular compartments as well as proliferation of crypt enterocytes with consequent remodelling of CD mucosa due to a cooperation of IL-15 and EGFR. 相似文献357.
Despite their importance for the spread of zoonotic diseases, our understanding of the dynamical aspects characterizing the movements of farmed animal populations remains limited as these systems are traditionally studied as static objects and through simplified approximations. By leveraging on the network science approach, here we are able for the first time to fully analyze the longitudinal dataset of Italian cattle movements that reports the mobility of individual animals among farms on a daily basis. The complexity and inter-relations between topology, function and dynamical nature of the system are characterized at different spatial and time resolutions, in order to uncover patterns and vulnerabilities fundamental for the definition of targeted prevention and control measures for zoonotic diseases. Results show how the stationarity of statistical distributions coexists with a strong and non-trivial evolutionary dynamics at the node and link levels, on all timescales. Traditional static views of the displacement network hide important patterns of structural changes affecting nodes' centrality and farms' spreading potential, thus limiting the efficiency of interventions based on partial longitudinal information. By fully taking into account the longitudinal dimension, we propose a novel definition of dynamical motifs that is able to uncover the presence of a temporal arrow describing the evolution of the system and the causality patterns of its displacements, shedding light on mechanisms that may play a crucial role in the definition of preventive actions. 相似文献
358.
359.
Maria Fusaro Luca Dalle Carbonare Adriana Dusso Maria Vittoria Arcidiacono Maria Teresa Valenti Andrea Aghi Sabina Pasho Maurizio Gallieni 《PloS one》2015,10(8)
Background
Warfarin, a widely used anticoagulant, is a vitamin K antagonist impairing the activity of vitamin K-dependent Bone Gla Protein (BGP or Osteocalcin) and Matrix Gla Protein (MGP). Because dabigatran, a new anticoagulant, has no effect on vitamin K metabolism, the aim of this study was to compare the impact of warfarin and dabigatran administration on bone structure and vascular calcification.Methods
Rats with normal renal function received for 6 weeks warfarin, dabigatran or placebo. Bone was evaluated immuno-histochemically and hystomorphometrically after double labelling with declomycin and calcein. Aorta and iliac arteries were examined histologically.Results
Histomorphometric analysis of femur and vertebrae showed significantly decreased bone volume and increased trabecular separation in rats treated with warfarin. Vertebra analysis showed that the trabecular number was higher in dabigatran treated rats. Osteoblast activity and resorption parameters were similar among groups, except for maximum erosion depth, which was higher in warfarin treated rats, suggesting a higher osteoclastic activity. Therefore, warfarin treatment was also associated with higher bone formation rate/bone surface and activation frequency. Warfarin treatment may cause an increased bone turnover characterized by increased remodelling cycles, with stronger osteoclast activity compared to the other groups. There were no differences among experimental groups in calcium deposition either in aortic or iliac arteries.Conclusions
These findings suggest for the first time that dabigatran has a better bone safety profile than warfarin, as warfarin treatment affects bone by reducing trabecular size and structure, increasing turnover and reducing mineralization. These differences could potentially result in a lower incidence of fractures in dabigatran treated patients. 相似文献360.
Cutaneous phototype is considered mainly related to cutaneous pigmentation and to the eumelanin/pheomelanin ratio, which is mostly genetically determined by the melanocortin 1 receptor (MC1R) polymorphisms. However, data in literature indicate that, in addition to stimulation of eumelanin synthesis, the MC1R signalling activates antioxidant, DNA repair and survival pathways. New emerging aspects regarding photoprotection and skin phototypes are going beyond those features connected to the melanin content in the skin. Important new findings link the MC1R to nuclear receptors activation, shedding light on new extra‐melanogenic effects dependent on the α‐melanocyte‐stimulating hormone (α‐MSH) activity and new ways through which such functions are modulated. These evidences indicate that several factors including melanin play a part in defining the basis for individual sun sensitivity, suggesting that the cutaneous phototype represents a ‘biochemical fingerprint’. 相似文献