7 research outputs found
Aqueous Nanocoating Approach to Strong Natural Microfibers with Tunable Electrical Conductivity for Wearable Electronic Textiles
Electronically
conductive and mechanically strong natural fibers
with desirable durability, flexibility, and environmental compatibility
are in great need for manufacturing multifunctional textiles. Here
we reveal a facile yet effective nanocoating approach to immobilization
of few-layer graphene oxide (GO) nanosheets at ramie fiber by hydrogen-bond-driven
self-assembly process under all-aqueous and additive-free condition.
The surface morphology and chemistry of GO-functionalized ramie fiber
(GOFR) were significantly altered with the homogeneous decoration
of trace amount of GO nanosheets, readying remarkable property improvements
and functionality realization. The tensile strength of GOFR (553 MPa)
witnessed an increase of over 25% compared to pristine ramie, as accompanied
by moderate promotion of extensibility with the assistance of robust
GO nanosheets. It is worth noting that exceptionally high electrical
conductivity was achieved for thermally reduced GOFR (rGOFR), with
values as high as 83.2 S/cm after reduction at 250 °C for only
30 min. By tuning the reduction time and temperature, the conductivity
of rGOFR was well controlled in an extremely wide range of 0.1–83.2
S/cm. This effort provides useful insights into the fabrication of
highly strong and conductive natural fibers in the promising field
of smart fabrics integrating high strength, flexibility, intelligent
functionality, and environmental compatibility
SS-GNN: A Simple-Structured Graph Neural Network for Affinity Prediction
Efficient and effective
drug-target binding affinity (DTBA) prediction
is a challenging task due to the limited computational resources in
practical applications and is a crucial basis for drug screening.
Inspired by the good representation ability of graph neural networks
(GNNs), we propose a simple-structured GNN model named SS-GNN to accurately
predict DTBA. By constructing a single undirected graph based on a
distance threshold to represent protein–ligand interactions,
the scale of the graph data is greatly reduced. Moreover, ignoring
covalent bonds in the protein further reduces the computational cost
of the model. The graph neural network-multilayer perceptron (GNN-MLP)
module takes the latent feature extraction of atoms and edges in the
graph as two mutually independent processes. We also develop an edge-based
atom-pair feature aggregation method to represent complex interactions
and a graph pooling-based method to predict the binding affinity of
the complex. We achieve state-of-the-art prediction performance using
a simple model (with only 0.6 M parameters) without introducing complicated
geometric feature descriptions. SS-GNN achieves Pearson’s Rp = 0.853 on the PDBbind v2016
core set, outperforming state-of-the-art GNN-based methods by 5.2%.
Moreover, the simplified model structure and concise data processing
procedure improve the prediction efficiency of the model. For a typical
protein–ligand complex, affinity prediction takes only 0.2
ms. All codes are freely accessible at https://github.com/xianyuco/SS-GNN
SS-GNN: A Simple-Structured Graph Neural Network for Affinity Prediction
Efficient and effective
drug-target binding affinity (DTBA) prediction
is a challenging task due to the limited computational resources in
practical applications and is a crucial basis for drug screening.
Inspired by the good representation ability of graph neural networks
(GNNs), we propose a simple-structured GNN model named SS-GNN to accurately
predict DTBA. By constructing a single undirected graph based on a
distance threshold to represent protein–ligand interactions,
the scale of the graph data is greatly reduced. Moreover, ignoring
covalent bonds in the protein further reduces the computational cost
of the model. The graph neural network-multilayer perceptron (GNN-MLP)
module takes the latent feature extraction of atoms and edges in the
graph as two mutually independent processes. We also develop an edge-based
atom-pair feature aggregation method to represent complex interactions
and a graph pooling-based method to predict the binding affinity of
the complex. We achieve state-of-the-art prediction performance using
a simple model (with only 0.6 M parameters) without introducing complicated
geometric feature descriptions. SS-GNN achieves Pearson’s Rp = 0.853 on the PDBbind v2016
core set, outperforming state-of-the-art GNN-based methods by 5.2%.
Moreover, the simplified model structure and concise data processing
procedure improve the prediction efficiency of the model. For a typical
protein–ligand complex, affinity prediction takes only 0.2
ms. All codes are freely accessible at https://github.com/xianyuco/SS-GNN
Design, Synthesis, and Biological Characterization of a Caspase 3/7 Selective Isatin Labeled with 2-[<sup>18</sup>F]fluoroethylazide
Imaging of programmed cell death (apoptosis) is important in the assessment of therapeutic response in oncology and for diagnosis in cardiac and neurodegenerative disorders. The executioner caspases 3 and 7 ultimately effect cellular death, thus providing selective molecular targets for in vivo quantification of apoptosis. To realize this potential, we aimed to develop 18F-labeled isatin sulfonamides with high metabolic stability and moderate lipophilicity while retaining selectivity and affinity for caspase 3/7. A small library of isatins modified with fluorinated aromatic groups and heterocycles was synthesized. A lead compound incorporating 2′-fluoroethyl-1,2,3-triazole was identified with subnanomolar affinity for caspase 3. “Click labeling” provided the 18F-labeled tracer in 65 ± 6% decay-corrected radiochemical yield from 2-[18F]fluoroethylazide. The compound showed high stability in vivo with rapid uptake and elimination in healthy tissues and tumor. The novel 18F-labeled isatin is a candidate radiotracer for further preclinical evaluation for imaging of apoptosis
Natural Fiber-Anchored Few-Layer Graphene Oxide Nanosheets for Ultrastrong Interfaces in Poly(lactic acid)
The development of high-performance
graphene oxide (GO) nanocomposites
is challenged by the lack of a feasible and effective route to disperse
and exfoliate GO nanosheets, as well as technical gaps in providing
precision control over the interfacial interactions. Here we disclose
an all-aqueous processing method to immobilize few-layer extended
GO nanosheets at ramie fiber
driven by hydrogen bonding. The reinforcing efficacy of GO-functionalized
ramie (GOFR) was examined in a poly(lactic acid) (PLA) matrix, wherein
the GOFR provided large active surfaces to induce chain ordering and
lamellar organization. It permitted the preferable formation of well-organized
PLA transcrystallinity at GOFR, in contrast to calabash-like and less-ordered
transcrystallinity induced by pristine ramie due to the inferior nucleation
activity. The transcrystallization kinetics and lamellar orientation
degree were significantly facilitated by the addition of chain mobility
accelerator in PLA, permitting the formation of prevailing transcrystallinity
with large sizes at GOFR. The profound control of interphase morphology
conferred remarkable improvements in interfacial properties with weak
relation to crystallization temperature, as indicated by an over 3-fold
increase in interfacial shear strength between GOFR and PLA matrix
compared to the counterparts incorporated with pristine ramie. The
effort reveals the appealing application of natural fibers as an ideal
template to extend GO nanosheets, potentially motivating further efforts
toward revolutionary advancements occurring in many fields of materials
science and nanotechnology
Nat Commun-De novo adipocyte differentiation from Pdgfrβ+ preadipocytes protects against pathologic visceral adipose expansion in obesity.pdf
Pathologic expansion of white adipose tissue (WAT) in obesity is characterized by adipocytehypertrophy, inflammation, and fibrosis; however, factors triggering this maladaptive remodelingare largely unknown. Here, we test the hypothesis that the potential to recruit newadipocytes from Pdgfrβ+ preadipocytes determines visceral WAT health in obesity. Wemanipulate levels of Pparg, the master regulator of adipogenesis, in Pdgfrβ+ precursors ofadult mice. Increasing the adipogenic capacity of Pdgfrβ+ precursors through Pparg overexpressionresults in healthy visceral WAT expansion in obesity and adiponectin-dependentimprovements in glucose homeostasis. Loss of mural cell Pparg triggers pathologic visceralWAT expansion upon high-fat diet feeding. Moreover, the ability of the TZD class of antidiabeticdrugs to promote healthy visceral WAT remodeling is dependent on mural cell Pparg.These data highlight the protective effects of de novo visceral adipocyte differentiation inthese settings, and suggest Pdgfrβ+ adipocyte precursors as targets for therapeutic interventionin diabetes.</div
