23 research outputs found
GRATIS: Deep Learning Graph Representation with Task-specific Topology and Multi-dimensional Edge Features
Graph is powerful for representing various types of real-world data. The
topology (edges' presence) and edges' features of a graph decides the message
passing mechanism among vertices within the graph. While most existing
approaches only manually define a single-value edge to describe the
connectivity or strength of association between a pair of vertices,
task-specific and crucial relationship cues may be disregarded by such manually
defined topology and single-value edge features. In this paper, we propose the
first general graph representation learning framework (called GRATIS) which can
generate a strong graph representation with a task-specific topology and
task-specific multi-dimensional edge features from any arbitrary input. To
learn each edge's presence and multi-dimensional feature, our framework takes
both of the corresponding vertices pair and their global contextual information
into consideration, enabling the generated graph representation to have a
globally optimal message passing mechanism for different down-stream tasks. The
principled investigation results achieved for various graph analysis tasks on
11 graph and non-graph datasets show that our GRATIS can not only largely
enhance pre-defined graphs but also learns a strong graph representation for
non-graph data, with clear performance improvements on all tasks. In
particular, the learned topology and multi-dimensional edge features provide
complementary task-related cues for graph analysis tasks. Our framework is
effective, robust and flexible, and is a plug-and-play module that can be
combined with different backbones and Graph Neural Networks (GNNs) to generate
a task-specific graph representation from various graph and non-graph data. Our
code is made publicly available at
https://github.com/SSYSteve/Learning-Graph-Representation-with-Task-specific-Topology-and-Multi-dimensional-Edge-Features
The Function of MicroRNAs in B-Cell Development, Lymphoma, and Their Potential in Clinical Practice
B-cell formation, development, and differentiation are complex processes regulated by several mechanisms. Recently, there has been growing evidence indicating that microRNAs (miRNAs) are important for normal B-cell lineage development. miRNAs are small non-coding RNA molecules, about 20–22 nucleotide in length, that play an important role in regulating gene expression. They pair with specific messenger RNAs (mRNAs), resulting in mRNAs translational repression or degradation. Here, we review current research about the function of miRNAs in the aspects of B-cell physiology and pathology. We start by introducing the process of miRNA biogenesis. We will then focus on the role of miRNAs during B-cell lineage commitment and development in the bone marrow, followed by a discussion of miRNAs’ role in subsequent peripheral B-cell activation, proliferation, and final differentiation (including B-cell central tolerance and autoimmunity). We list and describe several examples to illustrate miRNAs’ role in the development of B-cell lymphoma, both as oncogenes and tumor suppressor genes. Finally, we delineate the potential value of miRNAs in diagnosing B-cell lymphoma, predicting clinical outcomes, and modulating the efficiency of anticancer treatments. Despite the vast amount of research conducted on miRNAs in recent years, it is still necessary to increase and further strengthen studies on miRNAs and their targets to promote a better understanding on B-cell development and as a result, construct more effective treatments against B-cell disease
Selection of HBsAg-Specific DNA Aptamers Based on Carboxylated Magnetic Nanoparticles and Their Application in the Rapid and Simple Detection of Hepatitis B Virus Infection
Aptamers
are short single-stranded DNA or RNA oligonucleotides and can be selected
from synthetic combinatorial libraries in vitro. They have a high
binding affinity and specificity for their targets. Agarose gels,
nitrocellulose membranes, and adsorptive microplates are often used
as carriers to immobilize targets in the SELEX (systematic evolution
of ligands by exponential enrichment) process, but the subsequent
separation step is tedious and time-consuming. Therefore, we used
magnetic nanoparticles (MNPs) as carriers to immobilize the target,
hepatitis B surface antigen (HBsAg), which is convenient for fast
magnetic separation. In this study, we first selected DNA aptamers
against HBsAg by immobilizing HBsAg on the surface of carboxylated
MNPs. The ssDNA library of each selection round was prepared by asymmetric
PCR amplification for the next selection round. To obtain aptamer
sequences, the final selected products were purified by gel electrophoresis,
then cloned, and sequenced. DNA aptamers that specifically bind to
HBsAg were successfully obtained after 13 selection rounds. The selected
aptamers were used to construct a chemiluminescence aptasensor based
on magnetic separation and immunoassay to detect HBsAg from pure protein
or actual serum samples. There was a linear relationship between HBsAg
concentration and chemiluminescent intensity in the range of 1–200
ng/mL. The aptasensor worked well even in the presence of interfering
substances and was highly specific in the detection of HBsAg in serum
samples, with a detection limit 0.1 ng/mL lower than the 0.5 ng/mL
limit of an ELISA in use at the hospital. This aptasensor can contribute
to better detection of hepatitis B virus infection
Influence of Molecular Weight on Structure and Catalytic Characteristics of Ordered Mesoporous Carbon Derived from Lignin
Bio-renewable lignin has been used
as a carbon source for the preparation
of porous carbon materials. Nevertheless, up to now, there are few
studies about the influence of molecular weight of lignin on the structure
and morphology of the ordered mesoporous carbon. Here, we synthesized
the ordered mesoporous carbon derived from different molecular weights
of lignin and Pluronic F127. Fortunately, we found that molecular
weight is an important factor for obtaining highly ordered channels,
high specific surface area, and ordered mesoporous carbon. More importantly,
the narrow well-defined mesoporous channel could exert a spatial restriction
effect to some extent, which can serve as nanoreactors for efficient
reactions and enhance catalytic performance. The highly ordered mesoporous
carbon from lignin is a good candidate for Fischer–Tropsch
synthesis catalyst supports
Additively Manufactured Macroporous Titanium with Silver-Releasing Micro-/Nanoporous Surface for Multipurpose Infection Control and Bone Repair – A Proof of Concept
Restoring
large-scale bone defects, where osteogenesis is slow while infections
lurk, with biomaterials represents a formidable challenge in orthopedic
clinics. Here, we propose a scaffold-based multipurpose anti-infection
and bone repairing strategy to meet such restorative needs. To do
this, personalized multifunctional titanium meshes were produced through
an advanced additive manufacturing process and dual “TiO<sub>2</sub>–polyÂ(dopamine)/Ag (nano)” post modifications,
yielding macroporous constructs with micro-/nanoporous walls and nanosilver
bullets immobilized/embedded therein. Ultrahigh loading capacity and
durable release of Ag<sup>+</sup> were accomplished. The scaffolds
were active against planktonic/adherent bacteria (Gram-negative and
positive) for up to 12 weeks. Additionally, they not only defended
themselves from biofilm colonization but also helped destroy existing
biofilms, especially in combination with antibiotics. Further, the
osteoblasts/bacteria coculture study displayed that the engineered
surfaces aided MG-63 cells to combat bacterial invasion. Meanwhile,
the scaffolds elicited generally acceptable biocompatibility (cell
adhesion, proliferation, and viability) and hastened osteoblast differentiation
and maturation (alkaline phosphatase production, matrix secretion,
and calcification), by synergy of micro-/nanoscale topological cues
and bioactive catecholamine chemistry. Although done ex vivo, these
studies reveal that our three-in-one strategy (infection prophylaxis,
infection fighting, and bone repair) has great potential to simultaneously
prevent/combat infections and bridge defected bone. This work provides
new thoughts to the use of enabling technologies to design biomaterials
that resolve unmet clinical needs