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101.

It is critical to determine the methods by which coral colonies regenerate tissue lost to physical injury as they provide the physical structure of coral reef systems. To explore regeneration, circular lesions (12 mm diameter × 3 mm depth) were created in the fall of 2014 on 124 Montastraea cavernosa colonies located in the coastal waters of Grenada and Carriacou (10–12 m depth). Coral regeneration was documented at weekly intervals for 28 days. Repeated measures ANOVA on estimated weekly coral regeneration rates showed that island (p = 0.024) and colony colour (p = 0.024) were the only factors significantly affecting lesion regeneration. Mean rate of lesion closure during the first 28 days was approximately 2.8 mm2 d−1. Four identical circular lesions were created on 30 M. cavernosa colonies (Carriacou, 10–12 m depth) in the fall of 2015. One representative lesion created on each coral colony was re-sampled at each of 14, 21, and 32 or 33 days following injury, and coral tissue was flash-frozen. Tissues from 10 normally pigmented brown colonies were selected for proteomic analysis using tandem mass tags. The initial polyp sample, the day 14, and the final samples were used to quantify the difference in protein abundance as the lesions healed. In the tissue samples 6419 peptides were reliably identified, which corresponded to 906 unique proteins. During the first month of regeneration, 111 proteins were differentially abundant (p < 0.05) on at least one timepoint and of these, 11 were associated with regeneration. An additional 14 proteins were also identified that were differentially abundant (p < 0.05) and were associated with inflammation or antioxidant activity. This work demonstrates, for the first time, the differential abundance of proteins associated with regeneration in a scleractinian coral.

  相似文献   
102.
The prompt and accurate identification of bacterial pathogens is fundamental to patient health and outcome. Recent advances in matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) have revolutionized bacterial identification in the clinical laboratory, but uniform incorporation of this technology in the U.S. market has been delayed by a lack of FDA-cleared systems. In this study, we conducted a multicenter evaluation of the MALDI Biotyper CA (MBT-CA) System (Bruker Daltonics Inc, Billerica, MA) for the identification of aerobic gram-negative bacteria as part of a 510(k) submission to the FDA. A total of 2,263 aerobic gram negative bacterial isolates were tested representing 23 genera and 61 species. Isolates were collected from various clinical sources and results obtained from the MBT-CA System were compared to DNA sequencing and/or biochemical testing. Isolates that failed to report as a "high confidence species ID" [log(score) ≥2.00] were re-tested using an extraction method. The MBT-CA System identified 96.8% and 3.1% of isolates with either a "high confidence" or a "low confidence" [log(score) value between 1.70 and <2.00] species ID, respectively. Two isolates did not produce acceptable confidence scores after extraction. The MBT-CA System correctly identified 99.8% (2,258/2,263) to genus and 98.2% (2,222/2,263) to species level. These data demonstrate that the MBT-CA System provides accurate results for the identification of aerobic gram-negative bacteria.  相似文献   
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The P13K/Akt pathway is a growth-regulating cellular signaling pathway that is over-activated in numerous human cancers. A novel series of Akt pathway inhibitors were identified using iterative pharmacophore modeling, energy-based calculations, and property predictions of known Akt inhibitors. Inhibitory effects on activation of Akt and growth of human neoplastic cells are reported. Results show variable inhibitory effects of three selected compounds on Akt phosphorylation at a key activation site, and on proliferation of tumorigenic cells. We identify one lead compound with potent inhibitory activity on both human carcinoma cell proliferation and Akt activation.  相似文献   
105.
Lillie  Richard A.  Evrard  James O. 《Hydrobiologia》1994,279(1):235-246
Waterfowl and limnological data were monitored on Waterfowl Production Area (WPA) wetlands in northwestern Wisconsin over a 6-yr period (1983–88) to determine the impact of macroinvertebrates and macrophytes on waterfowl utilization. Interrelationships between limnological conditions and Waterfowl Breeding Pair Densities (BPDs reported as pairs/ha water surface) were analyzed using correlation and general linear model analysis techniques.Annual changes in waterfowl BPDs differed between wetlands according to differences in the structure of macrophyte communities and basin morphometry. The strength of associations differed between the two dominant waterfowl species. In a wetland dominated by dense stands of submersed vegetation, annual fluctuations in blue-winged teal (Anas discors) BPDs corresponded directly with changes in macrophyte biomass, but not with changes in macroinvertebrate density. In a nearby less densely vegetated wetland of similar water chemistry and trophic status, fluctuations in teal BPDs corresponded directly with changes in macroinvertebrate density, but not with changes in macrophyte biomass. These associations occurred despite a significant positive correlation between macroinvertebrates and macrophyte biomass in the latter habitat. Annual fluctuations in mallard (Anas platyrhynchos) BPDs were not correlated significantly with either macrophyte biomass or macroinvertebrate density in either wetland.  相似文献   
106.
The specific recognition of antigen by T cells is critical to the generation of adaptive immune responses in vertebrates. T cells recognize antigen using a somatically diversified T-cell receptor (TCR). All jawed vertebrates use four TCR chains called α, β, γ, and δ, which are expressed as either a αβ or γδ heterodimer. Nonplacental mammals (monotremes and marsupials) are unusual in that their genomes encode a fifth TCR chain, called TCRμ, whose function is not known but is also somatically diversified like the conventional chains. The origins of TCRμ are also unclear, although it appears distantly related to TCRδ. Recent analysis of avian and amphibian genomes has provided insight into a model for understanding the evolution of the TCRδ genes in tetrapods that was not evident from humans, mice, or other commonly studied placental (eutherian) mammals. An analysis of the genes encoding the TCRδ chains in the duckbill platypus revealed the presence of a highly divergent variable (V) gene, indistinguishable from immunoglobulin heavy (IgH) chain V genes (VH) and related to V genes used in TCRμ. They are expressed as part of TCRδ repertoire (VHδ) and similar to what has been found in frogs and birds. This, however, is the first time a VHδ has been found in a mammal and provides a critical link in reconstructing the evolutionary history of TCRμ. The current structure of TCRδ and TCRμ genes in tetrapods suggests ancient and possibly recurring translocations of gene segments between the IgH and TCRδ genes, as well as translocations of TCRδ genes out of the TCRα/δ locus early in mammals, creating the TCRμ locus.  相似文献   
107.

Background

Current influenza vaccines have reduced immunogenicity and are of uncertain efficacy in older adults. We assessed the safety and immunogenicity of MVA-NP+M1, a viral-vectored influenza vaccine designed to boost memory T cell responses, in a group of older adults.

Methods

Thirty volunteers (aged 50–85) received a single intramuscular injection of MVA-NP+M1 at a dose of 1·5×108 plaque forming units (pfu). Safety and immunogenicity were assessed over a period of one year. The frequency of T cells specific for nucleoprotein (NP) and matrix protein 1 (M1) was determined by interferon-gamma (IFN-γ) ELISpot, and their phenotypic and functional properties were characterized by polychromatic flow cytometry. In a subset of M1-specific CD8+ T cells, T cell receptor (TCR) gene expression was evaluated using an unbiased molecular approach.

Results

Vaccination with MVA-NP+M1 was well tolerated. ELISpot responses were boosted significantly above baseline following vaccination. Increases were detected in both CD4+ and CD8+ T cell subsets. Clonality studies indicated that MVA-NP+M1 expanded pre-existing memory CD8+ T cells, which displayed a predominant CD27+CD45RO+CD57CCR7 phenotype both before and after vaccination.

Conclusions

MVA-NP+M1 is safe and immunogenic in older adults. Unlike seasonal influenza vaccination, the immune responses generated by MVA-NP+M1 are similar between younger and older individuals. A T cell-inducing vaccine such as MVA-NP+M1 may therefore provide a way to circumvent the immunosenescence that impairs routine influenza vaccination.

Trial Registration

ClinicalTrials.gov NCT00942071  相似文献   
108.
109.
110.
Laupacis A  Lillie E  Dueck A  Straus S  Perrier L  Burton JM  Aviv R  Thorpe K  Feasby T  Spears J 《CMAJ》2011,183(16):E1203-E1212

Background:

It has been proposed by Zamboni and colleagues that multiple sclerosis is caused by chronic cerebrospinal venous insufficiency, a term used to describe ultrasound-detectable abnormalities in the anatomy and flow of intra- and extracerebral veins. We conducted a meta-analysis of studies that reported the frequency of chronic cerebrospinal venous insufficiency among patients with and those without multiple sclerosis.

Methods:

We searched MEDLINE and EMBASE as well as bibliographies of relevant articles for eligible studies. We included studies if they used ultrasound to diagnose chronic cerebrospinal venous insufficiency and compared the frequency of the venous abnormalities among patients with and those without multiple sclerosis.

Results:

We identified eight eligible studies: all included healthy controls, and four of them also included a control group of patients with neurologic diseases other than multiple sclerosis. Chronic cerebrospinal venous insufficiency was more frequent among patients with multiple sclerosis than among the healthy controls (odds ratio [OR] 13.5, 95% confidence interval [CI] 2.6–71.4), but there was extensive unexplained heterogeneity among the studies. The association remained significant in the most conservative sensitivity analysis (OR 3.7, 95% CI 1.2–11.0), in which we removed the initial study by Zamboni and colleagues and added a study that did not find chronic cerebrospinal venous insufficiency in any patient. Although chronic cerebrospinal venous insufficiency was also more frequent among patients with multiple sclerosis than among controls with other neurologic diseases (OR 32.5, 95% CI 0.6–1775.7), the association was not statistically significant, the 95% CI was wide, and the OR was less extreme after removal of the study by Zamboni and colleagues (OR 3.5, 95% 0.8–15.8).

Interpretation:

Our findings showed a positive association between chronic cerebrospinal venous insufficiency and multiple sclerosis. However, poor reporting of the success of blinding and marked heterogeneity among the studies included in our review precluded definitive conclusions.Multiple sclerosis is a chronic demyelinating and degenerative disease of the central nervous system. The exact cause remains unknown, but most evidence favours an autoimmune mechanism.1 In 2006, Zamboni and colleagues proposed that multiple sclerosis is caused by abnormalities in the direction and pathway of cerebral venous flow, leading to deposition of iron in the brain, which triggers an autoimmune reaction.2 They reported that patients with multiple sclerosis had a higher frequency of abnormalities of anatomy and flow in the internal jugular, deep cerebral, vertebral and azygous veins than individuals without multiple sclerosis had.3,4 They called this condition chronic cerebrospinal venous insufficiency. They further described detection of this condition by means of transcranial and extracranial Doppler ultrasonography. This method of detection requires the evaluation of five ultrasound parameters that assess both venous blood flow and anatomy.3,5 Chronic cerebrospinal venous insufficiency is diagnosed if a patient has an abnormality in two or more of the five parameters.There is controversy about the frequency and role of chronic cerebrospinal venous insufficiency in patients with multiple sclerosis6,7 and whether the frequency differs between patients with and those without multiple sclerosis. We performed a systematic review and meta-analysis of all peer-reviewed reports of studies that compared the frequency of chronic cerebrospinal venous insufficiency among patients with and those without multiple sclerosis.  相似文献   
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