Publications by authors named "Haifan Wu"

Objective: Bibliometrics was employed in this study to determine the research trends in the worldwide application of 3D printing technology to treat bone tumors over the previous 10 years.

Methods: Published from 2013 to 2022, the papers related to bone tumors treated with 3D printing were located in Web of Science Core Collection (WoSCC), PubMed, and Scopus. The screened articles were included in this bibliometric study.

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Expansion of intronic GGGGCC repeats in the gene causes amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. Transcription of the expanded repeats results in the formation of RNA-containing nuclear foci and altered RNA metabolism. In addition, repeat-associated non-AUG (RAN) translation of the expanded GGGGCC-repeat sequence results in the production of highly toxic dipeptide-repeat (DPR) proteins.

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Medical image segmentation is a compelling fundamental problem and an important auxiliary tool for clinical applications. Recently, the Transformer model has emerged as a valuable tool for addressing the limitations of convolutional neural networks by effectively capturing global relationships and numerous hybrid architectures combining convolutional neural networks (CNNs) and Transformer have been devised to enhance segmentation performance. However, they suffer from multilevel semantic feature gaps and fail to account for multilevel dependencies between space and channel.

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Semi-supervised medical image segmentation strives to polish deep models with a small amount of labeled data and a large amount of unlabeled data. The efficiency of most semi-supervised medical image segmentation methods based on voxel-level consistency learning is affected by low-confidence voxels. In addition, voxel-level consistency learning fails to consider the spatial correlation between neighboring voxels.

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Ion mobility spectrometry (IMS) coupled to mass spectrometry (MS) has become a versatile tool to fractionate complex mixtures, distinguish structural isomers, and elucidate molecular geometries. Along with the whole MS field, IMS/MS advances to ever larger species. A topical proteomic problem is the discovery and characterization of d-amino acid-containing peptides (DAACPs) that are critical to neurotransmission and toxicology.

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The Hippo pathway has important roles in organ development, tissue homeostasis and tumour growth. Its downstream effector TAZ is a transcriptional coactivator that promotes target gene expression through the formation of biomolecular condensates. However, the mechanisms that regulate the biophysical properties of TAZ condensates to enable Hippo signalling are not well understood.

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Acidic residues (Asp and Glu) have a high prevalence on protein surfaces, but cross-linking reactions targeting these residues are limited. Existing methods either require high-concentration coupling reagents or have low structural compatibility. Here a previously reported "plant-and-cast" strategy is extended to develop heterobifunctional cross-linkers.

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Objective: To assess the reliability of quantitative ultrasound (QUS) in diagnosing and screening osteoporosis in elder women.

Methods: We conducted a systematic search of the online databases, including PubMed, Embase, Web of Science, and China National Knowledge, and screened the studies according to the inclusion criteria. We directly extract or calculate the value of true positive (TP), false positive (FP), false negative (FN), and true negative (TN) from eligible studies.

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Problem: We aimed to explore the risk factors in patients with unexplained recurrent spontaneous abortion (URSA) and to provide a basis for clinically targeted therapy.

Method Of Study: This case-control study comprised 202 patients with URSA treated at our hospital and 115 women in early pregnancy with a normal birth history during the same period. After procuring the data we conducted a multivariate logistic regression analysis of risk factors related to URSA.

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Mutations in a microglia-associated gene 2 increase the risk of Alzheimer's disease. Currently, structural and functional studies of TREM2 mainly rely on recombinant TREM2 proteins expressed from mammalian cells. However, using this method, it is difficult to achieve site-specific labeling.

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Post-translational modification of proteins by Ubiquitin (Ub) and Ubiquitin-like proteins (Ubls) can be reversed by deconjugating enzymes, which have been implicated in different pathways and associated with various human diseases. To understand the activity and dynamics of deconjugating enzymes, multiple synthetic and semi-synthetic Ub/Ubl probes have been developed, and some of them have been applied to screen inhibitors of deconjugating enzymes. Since these Ub/Ubl probes are generally not cell-permeable, different strategies have been developed to deliver Ub/Ubl probes to live cells.

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Continuing advances in proteomics highlight the ubiquity and biological importance of proteoforms─proteins with varied sequence, splicing, or distribution of post-translational modifications (PTMs). The preeminent example is histones, where the PTM pattern encodes the combinatorial language controlling the DNA transcription central to life. While the proteoforms with distinct PTM compositions are distinguishable by mass, the isomers with permuted PTMs commonly coexisting in cells generally require separation before mass-spectrometric (MS) analyses.

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Genetically encoded non-canonical amino acids (ncAAs) with electrophilic moieties are excellent tools to investigate protein-protein interactions (PPIs) both and . These ncAAs, including a series of alkyl bromide-based ncAAs, mainly target cysteine residues to form protein-protein cross-links. Although some reactivities towards lysine and tyrosine residues have been reported, a comprehensive understanding of their reactivity towards a broad range of nucleophilic amino acids is lacking.

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Triggering receptor expressed on myeloid cells 2 (TREM2) is a single-pass transmembrane receptor of the immunoglobulin superfamily that is secreted in a soluble (sTREM2) form. Mutations in TREM2 have been linked to increased risk of Alzheimer's disease (AD). A prominent neuropathological component of AD is deposition of the amyloid-β (Aβ) into plaques, particularly Aβ40 and Aβ42.

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Amyloid imaging by positron emission tomography (PET) is an important method for diagnosing neurodegenerative disorders such as Alzheimer's disease. Many C- and F-labeled PET tracers show varying binding capacities, specificities, and affinities for their target proteins. The structural basis of these variations is poorly understood.

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Many neurodegenerative diseases such as Alzheimer's disease are characterized by pathological β-sheet filaments of the tau protein, which spread in a prion-like manner in patient brains. To date, high-resolution structures of tau filaments obtained from patient brains show that the β-sheet core only includes portions of the microtubule-binding repeat domains and excludes the C-terminal residues, indicating that the C-terminus is dynamically disordered. Here, we use solid-state NMR spectroscopy to identify the β-sheet core of full-length 0N3R tau fibrillized using heparin.

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Misfolding of the microtubule-binding protein tau into filamentous aggregates is characteristic of many neurodegenerative diseases such as Alzheimer's disease and progressive supranuclear palsy. Determining the structures and dynamics of these tau fibrils is important for designing inhibitors against tau aggregation. Tau fibrils obtained from patient brains have been found by cryo-electron microscopy to adopt disease-specific molecular conformations.

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Infrared (IR) spectroscopy has provided considerable insight into the structures, dynamics, and formation mechanisms of amyloid fibrils. IR probes, such as main chain C═O, have been widely employed to obtain site-specific structural information, yet only secondary structures and strand-to-strand arrangements can be probed. Very few nonperturbative IR probes are available to report on the side-chain conformation and environments, which are critical to determining sheet-to-sheet arrangements in steric zippers within amyloids.

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A family of proteases called caspases mediate apoptosis signaling in animals. We report a GFP-based fluorogenic protease reporter, dubbed "FlipGFP", by flipping a beta strand of the GFP. Upon protease activation and cleavage, the beta strand is restored, leading to reconstitution of the GFP and fluorescence.

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One of the fundamental events in protein folding is α-helix formation, which involves sequential development of a series of helical hydrogen bonds between the backbone C═O group of residues i and the -NH group of residues i + 4. While we now know a great deal about α-helix folding dynamics, a key question that remains to be answered is where the productive helical nucleation event occurs. Statistically, a helical nucleus (or the first helical hydrogen-bond) can form anywhere within the peptide sequence in question; however, the one that leads to productive folding may only form at a preferred location.

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Chemical cross-linking mass spectrometry (CXMS) is being increasingly used to study protein assemblies and complex protein interaction networks. Existing CXMS chemical cross-linkers target only Lys, Cys, Glu, and Asp residues, limiting the information measurable. Here we report a "plant-and-cast" cross-linking strategy that employs a heterobifunctional cross-linker that contains a highly reactive succinimide ester as well as a less reactive sulfonyl fluoride.

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Analogous to reversible post-translational protein modifications, the ability to attach and subsequently remove modifications on proteins would be valuable for protein and biological research. Although bioorthogonal functionalities have been developed to conjugate or cleave protein modifications, they are introduced into proteins on separate residues and often with bulky side chains, limiting their use to one type of control and primarily protein surface. Here we achieved dual control on one residue by genetically encoding S-propargyl-cysteine (SprC), which has bioorthogonal alkyne and propargyl groups in a compact structure, permitting usage in protein interior in addition to surface.

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Although helices play key roles in peptide-protein and protein-protein interactions, the helical conformation is generally unstable for short peptides (10-15 residues) in aqueous solution in the absence of their binding partners. Thus, stabilizing the helical conformation of peptides can lead to increases in binding potency, specificity, and stability towards proteolytic degradation. Helices have been successfully stabilized by introducing side chain-to-side chain crosslinks within the central portion of the helix.

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The folding of natural proteins typically relies on hydrophobic packing, metal binding, or disulfide bond formation in the protein core. Alternatively, a 3D structure can be defined by incorporating a multivalent cross-linking agent, and this approach has been successfully developed for the selection of bicyclic peptides from large random-sequence libraries. By contrast, there is no general method for the de novo computational design of multicross-linked proteins with predictable and well-defined folds, including ones not found in nature.

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The self-propagation of misfolded conformations of tau underlies neurodegenerative diseases, including Alzheimer's. There is considerable interest in discovering the minimal sequence and active conformational nucleus that defines this self-propagating event. The microtubule-binding region, spanning residues 244-372, reproduces much of the aggregation behaviour of tau in cells and animal models.

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