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121.
Although several primates respond negatively to inequity, it is unknown whether this results from homology or convergent processes. Behaviours shared within a taxonomic group are often assumed to be homologous, yet this distinction is important for a better understanding of the function of the behaviour. Previous hypotheses have linked cooperation and inequity responses. Supporting this, all species in which inequity responses have been documented are cooperative. In this study, we tested this hypothesis by investigating the response to inequity in squirrel monkeys, which share a phylogenetic family with capuchin monkeys, but do not cooperate extensively. Subjects exchanged tokens to receive food rewards in conditions in which the level of effort required and reward received varied. Squirrel monkeys did not respond negatively to inequity. However, the monkeys were sensitive to the variation present in the task; male subjects showed a contrast effect and, as in previous studies, subjects were more sensitive to differences in reward in the context of a task than when rewards were given for free. Taken with other results, these results support the hypothesis that a negative response to inequity evolved convergently in primates, probably as a mechanism for evaluating outcomes relative to one's partners in cooperative species. 相似文献
122.
Serghides L Kim H Lu Z Kain DC Miller C Francis RC Liles WC Zapol WM Kain KC 《PloS one》2011,6(11):e27714
The host immune response contributes to the onset and progression of severe malaria syndromes, such as cerebral malaria. Adjunctive immunomodulatory strategies for severe malaria may improve clinical outcome beyond that achievable with artemisinin-based therapy alone. Here, we report that prophylaxis with inhaled nitric oxide significantly reduced systemic inflammation (lower TNF, IFNγ and MCP-1 in peripheral blood) and endothelial activation (decreased sICAM-1 and vWF, and increased angiopoeitin-1 levels in peripheral blood) in an experimental cerebral malaria model. Mice that received inhaled nitric oxide starting prior to infection had reduced parasitized erythrocyte accumulation in the brain, decreased brain expression of ICAM-1, and preserved vascular integrity compared to control mice.Inhaled nitric oxide administered in combination with artesunate, starting as late as 5.5 days post-infection, improved survival over treatment with artesunate alone (70% survival in the artesunate only vs. 100% survival in the artesunate plus iNO group, p = 0.03). These data support the clinical investigation of inhaled nitric oxide as a novel adjunctive therapy in patients with severe malaria. 相似文献
123.
Deep sequencing reveals novel microRNAs and regulation of microRNA expression during cell senescence
In cell senescence, cultured cells cease proliferating and acquire aberrant gene expression patterns. MicroRNAs (miRNAs) modulate gene expression through translational repression or mRNA degradation and have been implicated in senescence. We used deep sequencing to carry out a comprehensive survey of miRNA expression and involvement in cell senescence. Informatic analysis of small RNA sequence datasets from young and senescent IMR90 human fibroblasts identifies many miRNAs that are regulated (either up or down) with cell senescence. Comparison with mRNA expression profiles reveals potential mRNA targets of these senescence-regulated miRNAs. The target mRNAs are enriched for genes involved in biological processes associated with cell senescence. This result greatly extends existing information on the role of miRNAs in cell senescence and is consistent with miRNAs having a causal role in the process. 相似文献
124.
Tony Chen Matthew J. Hilton Edward B. Brown Michael J. Zuscik Hani A. Awad 《Biotechnology and bioengineering》2013,110(5):1476-1486
A major challenge in cartilage tissue engineering is the need to recreate the native tissue's anisotropic extracellular matrix structure. This anisotropy has important mechanical and biological consequences and could be crucial for integrative repair. Here, we report that hydrodynamic conditions that mimic the motion‐induced flow fields in between the articular surfaces in the synovial joint induce the formation of a distinct superficial layer in tissue engineered cartilage hydrogels, with enhanced production of cartilage matrix proteoglycan and Type II collagen. Moreover, the flow stimulation at the surface induces the production of the surface zone protein Proteoglycan 4 (aka PRG4 or lubricin). Analysis of second harmonic generation signature of collagen in this superficial layer reveals a highly aligned fibrillar matrix that resembles the alignment pattern in native tissue's surface zone, suggesting that mimicking synovial fluid flow at the cartilage surface in hydrodynamic bioreactors could be key to creating engineered cartilage with superficial zone features. Biotechnol. Bioeng. 2013; 110: 1476–1486. © 2012 Wiley Periodicals, Inc. 相似文献
125.
Kamran Mohamad Reza Zargan Jamil alikhani Hani Keshavarz Hajinoormohamadi Ashkan 《International journal of peptide research and therapeutics》2020,26(4):1819-1828
International Journal of Peptide Research and Therapeutics - Bee venom (BV) has variety of properties, such as anti-inflammatory potential and anti-cancer activity.It has been shown that BV has... 相似文献
126.
Ilyse Darwish David Banner Samira Mubareka Hani Kim Rickvinder Besla David J. Kelvin Kevin C. Kain W. Conrad Liles 《PloS one》2013,8(8)
Rationale
Severe influenza remains a major public health threat and is responsible for thousands of deaths annually. Increasing antiviral resistance and limited effectiveness of current therapies highlight the need for new approaches to influenza treatment. Extensive pre-clinical data have shown that mesenchymal stromal (stem) cell (MSC) therapy can induce anti-inflammatory effects and enhance repair of the injured lung. We hypothesized that MSC therapy would improve survival, dampen lung inflammation and decrease acute lung injury (ALI) in a murine model of severe influenza.Methods
C57Bl/6 mice were infected with influenza A/PuertoRico/8/34 (mouse-adapted H1N1) or influenza A/Mexico/4108/2009 (swine-origin pandemic H1N1) and administered human or mouse MSCs via the tail vein, either pre- or post- infection. MSC efficacy was evaluated as both an independent and adjunctive treatment strategy in combination with the antiviral agent, oseltamivir. Weight loss and survival were monitored. Inflammatory cells, cytokine/chemokines (IFN-γ, CXCL10, CCL2 and CCL5) and markers of ALI (total protein and IgM), were measured in bronchoalveolar lavage fluid and lung parenchyma.Results
Administration of murine MSCs or human MSCs in a prophylactic or therapeutic regimen failed to improve survival, decrease pulmonary inflammation/inflammatory cell counts or prevent ALI in influenza virus-infected mice. MSCs administered in combination with oseltamivir also failed to improve outcomes.Conclusions
Despite similarities in the clinical presentation and pathobiology of ALI and severe influenza, our findings suggest that MSC therapy may not be effective for prevention and/or treatment of acute severe influenza. 相似文献127.
We describe the resolution of a planar chiral cationic iridium complex [Cp*Ir(η5‐2‐methyl‐oxodienyl)][OT f] ( 2 ) following the counterion strategy, where anion metathesis by Δ‐TRISPHAT generates the two diastereomers (pR, pS)‐[Cp*Ir(η5‐2‐methyl‐oxodienyl)][Δ‐TRISPHAT] ( 3a , 3a' ). Upon fractional crystallization both compounds were separated as confirmed by 1H nuclear magnetic resonance (NMR) and circular dichroism studies recorded in solution. The latter represents the key‐complex precursors for the enantioselective synthesis of metallated o‐quinone methide complexes ( 4a , 4a' ). Chirality 25:449–454, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
128.
Wasef Lamiaa G. Shaheen Hazem M. El-Sayed Yasser S. Shalaby Thanaa I. A. Samak Dalia H. Abd El-Hack Mohamed E. Al-Owaimer Abdullah Saadeldin Islam M. El-mleeh Amany Ba-Awadh Hani Swelum Ayman A. 《Biological trace element research》2020,193(2):456-465
Biological Trace Element Research - Healing of injuries caused by exposure to heat has been discussed in many studies, although a few drugs have been shown to produce satisfactory results. In this... 相似文献
129.
The ribosome accelerates the rate of peptidyl transfer by >10(6)-fold relative to the background rate. A widely accepted model for this rate enhancement invokes entropic effects whereby the ribosome and the 2'-OH of the peptidyl-tRNA substrate precisely position the reactive moieties through an extensive network of hydrogen bonds that allows proton movement through them. Some studies, however, have called this model into question because they find the 2'-OH of the peptidyl-tRNA to be dispensable for catalysis. Here, we use an in vitro reconstituted translation system to resolve these discrepancies. We find that catalysis is at least 100-fold slower with the dA76-substituted peptidyl-tRNA substrate and that the peptidyl transferase centre undergoes a slow inactivation when the peptidyl-tRNA lacks the 2'-OH group. Additionally, the 2'-OH group was found to be critical for EFTu binding and peptide release. These findings reconcile the conflict in the literature, and support a model where interactions between active site residues and the 2'-OH of A76 of the peptidyl-tRNA are pivotal in orienting substrates in this active site for optimal catalysis. 相似文献
130.