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41.
Division of labor in social insect colonies relies on a strong reproductive bias that favors queens. Although the ecological and evolutionary success attained through caste systems is well sketched out in terms of ultimate causes, the molecular and cellular underpinnings driving the development of caste phenotypes are still far from understood. Recent genomics approaches on honey bee developmental biology revealed a set of genes that are differentially expressed genes in larval ovaries and associated with transgressive ovary size in queens and massive cell death in workers. Amongst these, two contigs called special attention, both being over 200 bp in size and lacking apparent coding potential. Herein, we obtained their full cDNA sequences. These and their secondary structure characteristics placed in evidence that they are bona fide long noncoding RNAs (lncRNA) differentially expressed in larval ovaries, thus named lncov1 and lncov2. Genomically, both map within a previously identified QTL on chromosome 11, associated with transgressive ovary size in honey bee workers. As lncov1 was over-expressed in worker ovaries we focused on this gene. Real-time qPCR analysis on larval worker ovaries evidenced an expression peak coinciding with the onset of autophagic cell death. Cellular localization analysis through fluorescence in situ hybridization revealed perinuclear spots resembling omega speckles known to regulate trafficking of RNA-binding proteins. With only four lncRNAs known so far in honey bees, two expressed in the ovaries, these findings open a novel perspective on regulatory factors acting in the fine tuning of developmental processes underlying phenotypic plasticity related to social life histories. 相似文献
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Garrafa E Imberti L Tiberio G Prandini A Giulini SM Caimi L 《Immunology and cell biology》2011,89(3):475-481
As lymphatic endothelial cells (LECs) express different lymphatic and vascular markers depending on the organ they are derived from, we analysed whether they also show a heterogeneity of response against pathogens. To this end we analysed, for the presence of mRNA encoding for all human toll-like receptor (TLR), LECs isolated from lymph nodes and thymuses. RNA for TLR1-6 and 9 was identified in thymus-derived cells, whereas cells derived from lymph nodes contained mRNA for TLR1-4, 6 and 9, but failed to express mRNA specific for TLR5. The differential expression of TLRs was confirmed by the phosphorylation of nuclear factor-κB p65 only when the two types of LECs were incubated with the appropriate TLR agonists. The stimulation with specific agonists gives rise to a heterogeneous pattern of cytokine and chemokine secretion: thymus-derived LECs produced preferentially interleukin-6, interferon-inducible protein (IP)-10 and tumour necrosis factor-α, whereas cells prepared from lymph nodes mainly released interleukin-8, monocyte chemotactic protein-1, RANTES and (IP)-10. Finally, cells purified from lymph nodes expressed a higher level of intercellular adhesion molecule-1 than did cells prepared from the thymus when stimulated with several TLR agonists. The expression of a large set of TLRs and the responsiveness to specific agonists suggest that LECs are able to respond to pathogens, and the observed differences reflect specialized functions, redundancy and/or roles of LECs of different origin. 相似文献
43.
Enhancing the Adoption of Life Cycle Assessment by Small and Medium Enterprises Grouped in an Industrial Cluster: A Case Study of the Tanning Cluster in Tuscany (Italy) 下载免费PDF全文
Tiberio Daddi Benedetta Nucci Fabio Iraldo Francesco Testa 《Journal of Industrial Ecology》2016,20(5):1199-1211
Greenhouse gas emissions from small and medium enterprises (SMEs) account for 70% of the industrial pollution in the European Union. Owing to limited economic and human resources, only a few SMEs start procedures to evaluate the environmental impact of processes and products through life cycle assessment (LCA). In this work, a cluster life cycle assessment (Cluster‐LCA) is proposed as an instrument for the diffusion and realization of LCA analysis in clustered SMEs. This methodology is illustrated with a case study in the tanning cluster in Tuscany. The different characteristics of the methodology are analyzed by identifying the intrinsic strengths, weaknesses, opportunities, and threats. The application of this methodology in a particular cluster is then discussed in order to gather some helpful insight for the application of this methodology in different clusters. 相似文献
44.
Structure of D-prephenyllactate. A carboxycyclohexadienyl metabolite from Neurospora crassa 总被引:2,自引:0,他引:2
L O Zamir R Tiberio K A Devor F Sauriol S Ahmad R A Jensen 《The Journal of biological chemistry》1988,263(33):17284-17290
A novel natural product structurally related to prephenate and arogenate was isolated from a mutant of Neurospora crassa. This D-beta-(1-carboxy-4-hydroxy-2,5-cyclohexadiene-1-yl)-lactic acid is herein given the trivial name of D-prephenyllactate. The new metabolite is even more acid labile than is prephenate and is quantitatively converted to phenyllactate at mildly acidic pH. The structure characterization of prephenyllactate was performed using spectroscopic techniques (ultraviolet, 1H NMR, 13C NMR, two-dimensional heteronuclear experiments and mass spectrometry). Circular dichroism proved conclusively the R configuration of the asymmetric carbon at C-8 of prephenyllactate. Enzymatic utilization of prephenyllactate by cyclohexadienyl dehydratase and by cyclohexadienyl dehydrogenase from Klebsiella pneumoniae was demonstrated. 相似文献
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Antonelli D Turgeman Y Rosenfeld T 《International journal of cardiovascular interventions》2001,4(1):51-53
During the performance of 280 consecutive percutaneous balloon mitral valvuloplasty operations, two cases of conduction disturbances were reported (0.7%). These rare complications are transient and due to the mechanical pressure of the balloon on the conduction system. 相似文献
47.
Turgeman Y Bloch L Atar S Merin G Rosenfeld T 《International journal of cardiovascular interventions》2001,4(1):39-42
This paper presents a rare cause of angina pectoris in a 43-year-old woman. Her evaluation revealed a compressed and proximally occluded right coronary artery by a giant, unruptured, right sinus of Valsalva aneurysm. The aneurysm was surgically resected and the sinus was successfully reconstructed. On follow-up the patient is asymptomatic. 相似文献
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María Consuelo Marín-Togo Tiberio C. Monterrubio-Rico Katherine Renton Yamel Rubio-Rocha Claudia Macías-Caballero Juan Manuel Ortega-Rodríguez Ramón Cancino-Murillo 《Biodiversity and Conservation》2012,21(2):451-473
Ecological niche models provide useful predictions of species distributions, but may fail to detect reductions in distribution
due to factors other than habitat loss, such as hunting or trade. From 2001 to 2009, we conducted field-surveys along the
Mexican Pacific coast to obtain presence–absence data for nine Psittacidae species. We applied Genetic Algorithm for Rule
set Prediction (GARP) ecological niche modeling, using field-survey presence data to determine the potential current distribution
of each species, and incorporated absence data to delineate extirpation areas. All parrot species showed a reduced current
distribution, ranging from 9.6 to 79% reduction of estimated original distribution. The threatened and endemic species of
Amazona
oratrix, Amazona
finschi, and Forpus
cyanopygius suffered the greatest distribution reduction, higher than previously estimated by habitat-based models, suggesting that capture
for trade may have caused extirpation of these species. The greatest extent of current distribution was occupied by Aratinga
canicularis, Amazona
albifrons and Ara
militaris, which continue to occur throughout most of their original distribution. Amazona
auropalliata, Aratinga
strenua, and Brotogeris
jugularis also occur throughout their restricted distribution in coastal Chiapas, and show a relatively small distribution reduction,
but had the highest proportion of modified lands within their current distributions. Our results highlighted the regions of
coastal Guerrero, northern Nayarit, and southern Sinaloa where parrot species have been extirpated even though GARP models
predicted suitable habitat available. Ideally distribution models should be verified in the field to determine conservation
priorities, and efforts should be directed to maintain populations of species with greatest distribution reductions. 相似文献
50.
doi: 10.1111/j.1741‐2358.2012.00623.x Pulp sensibility test in elderly patients Background: The ageing process transforms the histological composition of the dental pulp and may affect the response to pulp sensibility tests. Objectives: The aim of this study was to assess the influence of age on pulp response time and on pain intensity. Material and methods: Fifty elderly patients and 50 young patients were selected. Different classes of teeth were evaluated. The pulp sensibility test was performed with a refrigerant spray. The pulp response time was measured in seconds and the pain intensity was assessed by visual analogue scale. Results: The Spearman coefficient was calculated and detect a positive correlation between age and pulp response time for maxillary incisors, premolars, mandibular incisors, and mean (p < 0.05). On the contrary, there was a negative correlation between age and pain intensity for maxillary incisors, mandibular incisors, and mean (p < 0.05). Also, the results of elderly and young groups were compared by Mann–Whitney test. Significant difference was noted regarding the pulp response time for maxillary incisors, premolars, mandibular incisors, and mean (p < 0.05). Significant difference was detected regarding the pain intensity for mandibular incisors only (p < 0.05). Conclusions: Pulp response time increases when people get older while pain intensity decreases. There were variations among the classes of teeth. 相似文献