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Giovanni Novembre Marco Zanon Giorgia Silani 《Social cognitive and affective neuroscience》2015,10(2):153-164
Recent research has shown that experiencing events that represent a significant threat to social bonds activates a network of brain areas associated with the sensory-discriminative aspects of pain. In the present study, we investigated whether the same brain areas are involved when witnessing social exclusion threats experienced by others. Using a within-subject design, we show that an ecologically valid experience of social exclusion recruits areas coding the somatosensory components of physical pain (posterior insular cortex and secondary somatosensory cortex). Furthermore, we show that this pattern of activation not only holds for directly experienced social pain, but also during empathy for social pain. Finally, we report that subgenual cingulate cortex is the only brain area conjointly active during empathy for physical and social pain. This supports recent theories that affective processing and homeostatic regulation are at the core of empathic responses. 相似文献
153.
Moria J. Smoski Shian-Ling Keng Jie Lisa Ji Tyler Moore Jared Minkel Gabriel S. Dichter 《Social cognitive and affective neuroscience》2015,10(9):1187-1194
Mood disorders are characterized by impaired emotion regulation abilities, reflected in alterations in frontolimbic brain functioning during regulation. However, little is known about differences in brain function when comparing regulatory strategies. Reappraisal and emotional acceptance are effective in downregulating negative affect, and are components of effective depression psychotherapies. Investigating neural mechanisms of reappraisal vs emotional acceptance in remitted major depressive disorder (rMDD) may yield novel mechanistic insights into depression risk and prevention. Thirty-seven individuals (18 rMDD, 19 controls) were assessed during a functional magnetic resonance imaging task requiring reappraisal, emotional acceptance or no explicit regulation while viewing sad images. Lower negative affect was reported following reappraisal than acceptance, and was lower following acceptance than no explicit regulation. In controls, the acceptance > reappraisal contrast revealed greater activation in left insular cortex and right prefrontal gyrus, and less activation in several other prefrontal regions. Compared with controls, the rMDD group had greater paracingulate and right midfrontal gyrus (BA 8) activation during reappraisal relative to acceptance. Compared with reappraisal, acceptance is associated with activation in regions linked to somatic and emotion awareness, although this activation is associated with less reduction in negative affect. Additionally, a history of MDD moderated these effects. 相似文献
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Milena Dropa Barbara Ghiglione Maria Helena Matté Livia Carminato Balsalobre Nilton Lincopan Glavur Rogério Matté Gabriel Gutkind Pablo Power 《Antimicrobial agents and chemotherapy》2015,59(3):1815-1817
CTX-M-131 is a natural Asp240Gly variant from the CTX-M-2 group detected in a Providencia rettgeri clinical strain from Brazil. Molecular analysis showed that blaCTX-M-131 was inserted in a complex class 1 integron harbored by a 112-kb plasmid, which has not been previously described as a platform for CTX-M-encoding genes with the Asp240Gly mutation. Steady-state kinetic parameters showed that the enzyme has a typical cefotaximase catalytic profile and an enhanced activity against ceftazidime. 相似文献
156.
Matthew E. Wand Kate S. Baker Gabriel Benthall Hannah McGregor James W. I. McCowen Ana Deheer-Graham J. Mark Sutton 《Antimicrobial agents and chemotherapy》2015,59(7):3966-3972
The EGD Murray collection consists of approximately 500 clinical bacterial isolates, mainly Enterobacteriaceae, isolated from around the world between 1917 and 1949. A number of these “Murray” isolates have subsequently been identified as Klebsiella pneumoniae. Antimicrobial susceptibility testing of these isolates showed that over 30% were resistant to penicillins due to the presence of diverse blaSHV β-lactamase genes. Analysis of susceptibility to skin antiseptics and triclosan showed that while the Murray isolates displayed a range of MIC/minimal bactericidal concentration (MBC) values, the mean MIC value was lower than that for more modern K. pneumoniae isolates tested. All Murray isolates contained the cation efflux gene cepA, which is involved in disinfectant resistance, but those that were more susceptible to chlorhexidine were found to have a 9- or 18-bp insertion in this gene. Susceptibility to other disinfectants, e.g., H2O2, in the Murray isolates was comparable to that in modern K. pneumoniae isolates. The Murray isolates were also less virulent in Galleria and had a different complement of putative virulence factors than the modern isolates, with the exception of an isolate related to the modern lineage CC23. More of the modern isolates (41% compared to 8%) are classified as good/very good biofilm formers, but there was overlap in the two populations. This study demonstrated that a significant proportion of the Murray Klebsiella isolates were resistant to penicillins before their routine use. This collection of pre-antibiotic era isolates may provide significant insights into adaptation in K. pneumoniae in relation to biocide susceptibility. 相似文献
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158.
Kevin W. Sexton Charles L. Rodriguez-Feo Richard B. Boyer Gabriel A. Del Corral David C. Riley Alonda C. Pollins Nancy L. Cardwell R. Bruce Shack Lillian B. Nanney Wesley P. Thayer 《Hand (New York, N.Y.)》2015,10(4):688-694
Background
Hydrophilic polymers have been shown to improve physiologic recovery following repair of transected nerves with microsutures. Our study was designed to combine hydrophilic polymer therapy with nerve tubes (NT) to enhance polymer delivery to the site of nerve injury.Methods
Using a rat sciatic nerve injury model, a single transection injury was repaired in an end-to-end fashion with NT + polyethylene glycol (PEG) to NT alone. Compound action potentials (CAPs) were recorded before nerve transection and after repair. Behavioral testing was performed for 5 weeks.Results
PEG therapy restored CAPS in all, but one, animals, while no CAPS were recorded in animals not receiving PEG. Behavioral nerve function was measured using the standardized functional assessment technique and foot fault asymmetry scores (FF). FF scores were improved for the PEG therapy groups on postoperative days 7, 14, and 21. However, after expected eventual axonal outgrowth, the benefit was less noticeable at days 28 and 35. Immunohistochemistry of the distal axon segments showed an increase number of sensory and motor axons in the NT + PEG group as compared to NT alone.Conclusion
These data suggest that PEG delivery via a conduit may provide a simple, effective way to fuse severed axons and regain early nerve function. For proximal nerve injuries in large animals, recovery of axonal continuity could dramatically improve outcomes, even if fusion only occurs in a small percentage of axons. 相似文献159.
Andrés?Felipe?Duque AmayaEmail author Adalberto?Gabriel?Díaz Torres Diego?Andrés?Acosta Maya 《International Journal on Interactive Design and Manufacturing》2016,10(4):401-415
A mathematical and numerical model of flow and combustion process for spark ignition engines is developed using the principles of the first and second law of thermodynamic. Availability (exergy) analysis is applied to cylinder of a spark ignition engine during the combustion process using a two-zone combustion model. Special attention is given to identification and quantification of irreversibility of combustion process and energy available basing on the isooctane fuel explosion. To predict emissions generation (greenhouse gases) a skeletal mechanism including 32 species and 61 reactions was developed and tested for different engine operations and exergy destructions. 相似文献
160.