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1.
Delia V?rg? Petru Lucian Cur?eu Lauren?iu Maricu?oiu Florin A. Sava Irina Macsinga Silvia M?gurean 《PloS one》2014,9(11)
This study seeks to explore whether neuroticism, agreeableness, and conscientiousness moderate the influence of relationship conflict experienced in groups on changes in group members'' evaluative cognitions related to teamwork quality (teamwork-related mental models). Data from 216 students, nested in 48 groups were analyzed using a multilevel modeling approach. Our results show that the experience of relationship conflict leads to a negative shift from the pre-task to the post-task teamwork-related mental models. Moreover, the results indicate that conscientiousness buffered the negative association between relationship conflict and the change in teamwork-related mental models. Our results did not support the hypothesized moderating effect of agreeableness and show that the detrimental effect of relationship conflict on the shift in teamwork-related mental models is accentuated for group members scoring low rather than high on neuroticism. These findings open new research venues for exploring the association between personality, coping styles and change in teamwork-related mental models. 相似文献
2.
Joanne K. Gardner Cyril D. S. Mamotte Priya Patel Teong Ling Yeoh Connie Jackaman Delia J. Nelson 《PloS one》2015,10(4)
Dendritic cells (DCs) play an important role in the generation of anti-cancer immune responses, however there is evidence that DCs in cancer patients are dysfunctional. Lipid accumulation driven by tumor-derived factors has recently been shown to contribute to DC dysfunction in several human cancers, but has not yet been examined in mesothelioma. This study investigated if mesothelioma tumor cells and/or their secreted factors promote increases in DC lipid content and modulate DC function. Human monocyte-derived DCs (MoDCs) were exposed to human mesothelioma tumor cells and tumor-derived factors in the presence or absence of lipoproteins. The data showed that immature MoDCs exposed to mesothelioma cells or factors contained increased lipid levels relative to control DCs. Lipid accumulation was associated with reduced antigen processing ability (measured using a DQ OVA assay), upregulation of the co-stimulatory molecule, CD86, and production of the tolerogenic cytokine, IL-10. Increases in DC lipid content were further enhanced by co-exposure to mesothelioma-derived factors and triglyceride-rich lipoproteins, but not low-density lipoproteins. In vivo studies using a murine mesothelioma model showed that the lipid content of tumor-infiltrating CD4+CD8α- DCs, CD4-CD8α- DCs DCs and plasmacytoid DCs increased with tumor progression. Moreover, increasing tumor burden was associated with reduced proliferation of tumor-antigen-specific CD8+ T cells in tumor-draining lymph nodes. This study shows that mesothelioma promotes DC lipid acquisition, which is associated with altered activation status and reduced capacity to process and present antigens, which may impair the ability of DCs to generate effective anti mesothelioma T cell responses. 相似文献
3.
Homing to a more or less permanent scar after each foragingexcursion is a common movement pattern among intertidal gastropodsand chitons; however, details of the timing and spacing of foragingactivity have been investigated only in a few species. The presentstudy analyzes the short-term behavior of the limpet Patellarustica along the Tyrrhenian coast, Italy, using a motographictechnique to assess the fine organization of its foraging duringfavorable periods of sea roughness. P. rustica becomes activeonce the upper midlittoral is well splashed. It alternates foragingexcursions and resting at home with a periodicity slightly longerthan 12 h, suggesting a tidal-diel pattern. However, periodogramanalysis of the sea level oscillations during the study periodsrevealed no such rhythmicity because tidal oscillations werehidden by irregular variations caused by waves. As a resultof this time partitioning, limpets move, on average, less than50% of their potential activity time. Time partitioning maybe highly adaptive in reducing potential risks. Nevertheless,in the absence of clear external driving cues, the significanceof a very regular and apparently tidal pattern, fairly synchronousamong the different specimens, remains to be explained. Theactivity of P. rustica during each excursion is organized intothree parts: the outgoing journey during which grazing activityprogressively increases, a central part characterized by intensegrazing, and the return characterized by fast displacement anda more or less consistent trail following. Limpets head forrandom directions to reach foraging grounds in successive excursions,showing only a slight avoidance of the direction taken duringthe previous outward journey. This pattern produces a spatialscattering of grazing activity, allowing efficient exploitationof grazing areas distributed radially around home during subsequentexcursions. 相似文献
4.
To be able to understand cellular mechanisms, we require fully integrated data sets combining information about gene expression, protein expression, post-translational modification states, sub-cellular location and complex formation. Proteomics is a very powerful technique that can be applied to interrogate changes at the protein level. Studying this effectively requires specialised facilities within research institutes. Here, we describe the setting up and operation of such a facility, providing a resource for the Arabidopsis and Drosophila research communities. 相似文献
5.
Chen H Sun H You F Sun W Zhou X Chen L Yang J Wang Y Tang H Guan Y Xia W Gu J Ishikawa H Gutman D Barber G Qin Z Jiang Z 《Cell》2011,147(2):436-446
STAT6 plays a prominent role in adaptive immunity by transducing signals from extracellular cytokines. We now show that STAT6 is required for innate immune signaling in response to virus infection. Viruses or cytoplasmic nucleic acids trigger STING (also named MITA/ERIS) to recruit STAT6 to the endoplasmic reticulum, leading to STAT6 phosphorylation on Ser(407) by TBK1 and Tyr(641), independent of JAKs. Phosphorylated STAT6 then dimerizes and translocates to the nucleus to induce specific target genes responsible for immune cell homing. Virus-induced STAT6 activation is detected in all cell-types tested, in contrast to the cell-type specific role of STAT6 in cytokine signaling, and Stat6(-/-) mice are susceptible to virus infection. Thus, STAT6 mediates immune signaling in response to both cytokines at the plasma membrane, and virus infection at the endoplasmic reticulum. 相似文献
6.
Copper, an essential trace element acquired through nutrition, is an important co-factor for pro-angiogenic factors including vascular endothelial growth factor (VEGF). Decreasing bioavailable copper has been used as an anti-angiogenic and anti-cancer strategy with promising results. However, the role of copper and its potential as a therapy in mesothelioma is not yet well understood. Therefore, we monitored copper levels in progressing murine mesothelioma tumors and analyzed the effects of lowering bioavailable copper. Copper levels in tumors and organs were assayed using atomic absorption spectrophotometry. Mesothelioma tumors rapidly sequestered copper at early stages of development, the copper was then dispersed throughout growing tumor tissues. These data imply that copper uptake may play an important role in early tumor development. Lowering bioavailable copper using the copper chelators, penicillamine, trientine or tetrathiomolybdate, slowed in vivo mesothelioma growth but did not provide any cures similar to using cisplatin chemotherapy or anti-VEGF receptor antibody therapy. The impact of copper lowering on tumor blood vessels and tumor infiltrating T cells was measured using flow cytometry and confocal microscopy. Copper lowering was associated with reduced tumor vessel diameter, reduced endothelial cell proliferation (reduced Ki67 expression) and lower surface ICAM/CD54 expression implying reduced endothelial cell activation, in a process similar to endothelial normalization. Copper lowering was also associated with a CD4+ T cell infiltrate. In conclusion, these data suggest copper lowering is a potentially useful anti-mesothelioma treatment strategy that slows tumor growth to provide a window of opportunity for inclusion of other treatment modalities to improve patient outcomes. 相似文献
7.
Raffaele De Vita Delia Cavallo Luigi Raganella Patrizia Eleuteri Maria G. Grollino Alberto Calugi 《Bioelectromagnetics》1995,16(5):330-334
Flow cytometry (FCM) was performed to monitor the cellular effects of extremely-low-frequency magnetic field on mouse spermatogenesis. Groups of five male hybrid F1 mice aged 8–10 weeks were exposed to 50 Hz magnetic field. The strength of the magnetic field was 1.7 mT. Exposure times of 2 and 4 h were chosen. FCM measurements were performed 7, 14, 21, 28, 35, and 42 days after treatment. For each experimental point, a sham-treated group was used as a control. The possible effects were studied by analyzing the DNA content distribution of the different cell types involved in spermatogenesis and using the elongated spermatids as the reference population. The relative frequencies of the various testicular cell types were calculated using specific software. In groups exposed for 2 h, no effects were observed. In groups exposed for 4 h, a statistically significant (P < 0.001) decrease in elongated spermatids was observed at 28 days after treatment. This change suggests a possible cytotoxic and/or cytostatic effect on differentiating spermatogonia. However, further studies are being carried out to investigate the effects of longer exposure times. © 1995 Wiley-Liss, Inc. 相似文献
8.
Irene Faravelli Megi Meneri Domenica Saccomanno Daniele Velardo Elena Abati Delia Gagliardi Valeria Parente Lucia Petrozzi Dario Ronchi Nino Stocchetti Edoardo Calderini Grazia D’Angelo Giovanna Chidini Edi Prandi Giulia Ricci Gabriele Siciliano Nereo Bresolin Giacomo Pietro Comi Stefania Corti Francesca Magri Alessandra Govoni 《Journal of cellular and molecular medicine》2020,24(5):3034-3039
The antisense oligonucleotide Nusinersen has been recently licensed to treat spinal muscular atrophy (SMA). Since SMA type 3 is characterized by variable phenotype and milder progression, biomarkers of early treatment response are urgently needed. We investigated the cerebrospinal fluid (CSF) concentration of neurofilaments in SMA type 3 patients treated with Nusinersen as a potential biomarker of treatment efficacy. The concentration of phosphorylated neurofilaments heavy chain (pNfH) and light chain (NfL) in the CSF of SMA type 3 patients was evaluated before and after six months since the first Nusinersen administration, performed with commercially available enzyme-linked immunosorbent assay (ELISA) kits. Clinical evaluation of SMA patients was performed with standardized motor function scales. Baseline neurofilament levels in patients were comparable to controls, but significantly decreased after six months of treatment, while motor functions were only marginally ameliorated. No significant correlation was observed between the change in motor functions and that of neurofilaments over time. The reduction of neurofilament levels suggests a possible early biochemical effect of treatment on axonal degeneration, which may precede changes in motor performance. Our study mandates further investigations to assess neurofilaments as a marker of treatment response. 相似文献
9.
Muriel Cario Catherine Pain Priscilla Kaulanjan‐Checkmodine Daniela Masia Gabriele Delia Vincent Casoli Pierre Costet Jean‐Franois Goussot Vronique Guyonnet‐Duperat Alice Bibeyran Khaled Ezzedine Corinne Reymermier Valrie Andre‐Frei Alain Taieb 《Pigment cell & melanoma research》2020,33(3):435-445
Human skin melanin pigmentation is regulated by systemic and local factors. According to the type of melanin produced by melanocytes, the transfer and degradation of melanosomes differ, thus accounting for most variations between ethnicities. We made the surprising observation that in a drastically changed environment, white and black phenotypes are reversible since Caucasian skin grafted onto nude mice can become black with all black phenotypic characteristics. Black xenografts differed essentially from other grafts by the levels of epidermal FGF‐2 and keratin 5. In vitro analysis confirmed that FGF‐2 directly regulates keratin 5. Interestingly, this phenomenon may be involved in human pathology. Keratin 5 mutations in Dowling–Degos Disease (DDD) have already been associated with the pheomelanosome–eumelanosome transition. In a DDD patient, keratin 5 was expressed in the basal and spinous layers, as observed in black xenografts. Furthermore, in a common age‐related hyperpigmentation disorder like senile lentigo (SL), keratin 5 distribution is also altered. In conclusion, modulation of keratin 5 expression and distribution either due to mutations or factors may account for the development of pigmentary disorders. 相似文献
10.
Yannery Gómez-Bonilla Miguel López-Ferber Primitivo Caballero Rosa Murillo Delia Muñoz 《BioControl》2013,58(2):215-224
The control efficiency of a Phthorimaea operculella granulovirus isolate from Costa Rica (PhopGV-CR1) against the concurrent insect pests P. operculella (Zeller) and Tecia solanivora (Povolny) (Lepidoptera: Gelechiidae) was evaluated. In warehouses, the best control efficiency was achieved with a powder formulate applied inside bags, which reduced injury over 70 % compared with the untreated controls. In the field, liquid and powder virus formulations significantly reduced injury between 56.2 and 81.7 % compared with the untreated controls, and were as efficient as chemical treatments. The efficiency of formulations stored at ?20 °C for six months (liquid) or at ambient temperature for three months (powder) was maintained, but higher temperatures and/or longer exposure times resulted in loss of pathogenicity. The data presented here favor the inclusion of granulovirus formulations of PhopGV-CR1 in Integrated Pest Management programs against tuberworms in Costa Rica and give clues on storage conditions for the growers in this country. 相似文献