487 research outputs found
Investigation into the Diversity of the Asia-Pacific Region and Scope for Collaboration Report on Research Project
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Elegant Chemistry to Directly Anchor Intact Saccharides on Solid Surfaces Used for the Fabrication of Bioactivity-Conserved Saccharide Microarrays
An easy chemical strategy was proposed and used to establish
a
method for direct anchoring of intact saccharides on solid surfaces
with well conserved bioaffinity. The anchoring was achieved by temperature-modulated
stepwise reactions with cyanuric chloride as a key linker, and was
successfully applied to the fabrication of saccharide chips. To demonstrate,
15 intact reducing and nonreducing saccharides with various molecular
sizes were dotted on a cyanuric-chloride-modified chip (1.0 Γ
1.0 cm<sup>2</sup>) and made to react with lectins. As expected, the
anchored saccharides were capable of recognizing their target lectins,
and more exciting were the perfect conservation of the specific recognizing
ability of the anchored monosaccharides such as mannose, glucose,
and even fructose (interacting only weakly with concanavalin A). This
conservation was ascribed to the maintenance of the original structure
(especially the anomeric configuration) of saccharides after immobilization
and to the allowance of the anchored saccharides to rotate with and/or
on the scaffold of cyanuric chloride, which makes them easily adapt
to the recognition-preferred spatial position. The expected linkage
of saccharides on cyanuric chloride and the maintenance of their anomeric
configuration were characterized by mass spectrometry and nuclear
magnetic resonance, respectively. The new method can be highlighted
not only by its conservation of saccharide bioaffinity and universal
applicability but also by its merits of easy manipulation or facile
control of the reactions and cost-effectiveness due to the use of
extremely cheap cyanuric chloride
Physical Activity and Risks of Esophageal and Gastric Cancers: A Meta-Analysis
<div><p>Background</p><p>The incidence of esophageal and gastric cancer has been increasing rapidly worldwide in recent years, although the reason for this increase is unclear. Here, a statistical synthesis of studies that evaluated the association between physical activity, a well-known protecting factor against death and other chronic diseases, and the risk of esophageal and gastric cancer was performed.</p><p>Methods</p><p>Potentially suitable studies were identified using Medline and Embase. The reference lists of all included articles and those of several recent reviews were searched manually. Studies were included if they (1) were published as case-control or cohort studies evaluating the association between physical activity and risk of esophageal or gastric cancer; and (2) reported point estimates (i.e., risk ratios, odds ratios) and measures of variability (i.e., 95% confidence intervals [CIs]) for physical activity and risk of esophageal or gastric cancer.</p><p>Results</p><p>Fifteen studies were identified (7 cohorts, 8 case-controls; 984 esophageal and 7,087 gastric cancers). Collectively, they indicated that the risk of gastric cancer was 13% lower among the most physically active people than among the least active people (RRβ=β0.87, 95% confidence interval [CI]β=β0.78 to 0.97) and that of esophageal cancer was 27% lower (RRβ=β0.73, 95% CIβ=β0.56 to 0.97).</p><p>Conclusions</p><p>Pooled results from observational studies support a protective effect of physical activity against both esophageal and gastric cancer.</p></div
Surface Plasmon Resonance Imaging Detection of Sub-femtomolar MicroRNA
MicroRNA (miRNA)
is a promising new type of biomarkers but at a low fM level and hard
to be analyzed. Herein proposed is an innovated surface plasmon resonance
imaging (SPRi) method merged with a novel in-plane and vertical signal
amplification strategy, that is, orthogonal signal amplification to
enable a direct determination of sub-fM miRNA-15a (a multiple tumor
diagnostic biomarker). The core idea is to add more mass on a target
sample spot first along the surficial direction, then upward from
the surface. In detection of miRNA, this was realized by coupling
a miRNA-initiated surficial cyclic DNAβDNA hybridization reaction
with a DNA-initiated upward cyclic polymerization reaction. A perfect
SPRi sensing chip with isolated gold islands bordered by hydrophobic
CYTOP was fabricated and used to obtain high-quality chip with low
fabrication difficulty. As a result, SPRi contrast largely increases,
able to reach a limit of detection and limit of quantification down
to 0.56 and 5fM for miRNA-15a, about 10<sup>7</sup>-fold improvement
of sensitivity compared with a common SPRi detection. The method could
quantify standard miRNA-15a spiked in human serum with an ideal recovery
ranging from 98.6% to 104.9% and was validated to be applicable to
the direct determination of miRNA-15a in healthy and cancer human
serums. The orderly and controllable in situ sensitizing strategy
is powerful and readily extendable to detection of other miRNAs
Main characteristics of the studies in the primary meta-analysis that have investigated the association between PA and GC and EC.
<p>Main characteristics of the studies in the primary meta-analysis that have investigated the association between PA and GC and EC.</p
Framework of computational intelligence-aided design.
<p>Framework of computational intelligence-aided design.</p
Schematic of a dual-layer cathode electrode of a PEFC.
<p>Schematic of a dual-layer cathode electrode of a PEFC.</p
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