Publications by authors named "Kexiang Xu"

Temporal control of protein levels in cells and living animals can be used to improve our understanding of protein function. In addition, control of engineered proteins could be used in therapeutic applications. PRoteolysis-TArgeting Chimeras (PROTACs) have emerged as a small-molecule-driven strategy to achieve rapid, post-translational regulation of protein abundance via recruitment of an E3 ligase to the target protein of interest.

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Purpose: Despite the success of chimeric antigen receptor (CAR) T-cell therapy against hematologic malignancies, successful targeting of solid tumors with CAR T cells has been limited by a lack of durable responses and reports of toxicities. Our understanding of the limited therapeutic efficacy in solid tumors could be improved with quantitative tools that allow characterization of CAR T-targeted antigens in tumors and accurate monitoring of response.

Experimental Design: We used a radiolabeled FAP inhibitor (FAPI) [18F]AlF-FAPI-74 probe to complement ongoing efforts to develop and optimize FAP CAR T cells.

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The simultaneous therapy of tumor recurrence and bone defects resulting from surgical resection of osteosarcoma is still a challenge in the clinic. Combination therapy based on a localized drug-delivery system shows great promise in the treatment of osteosarcoma. Herein, bifunctional polydopamine (PDA)-modified curcumin (CM)-loaded silk fibroin (SF) composite (SF/CM-PDA) nanofibrous scaffolds, which combined photothermal therapy with chemotherapy to synergistically enhance osteosarcoma therapy, were prepared by PDA coating of the SF/CM nanofibrous scaffolds fabricated by supercritical carbon dioxide (SC-CO) technology.

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Background: Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic disease among children, the etiology of which involves a strong genetic component, but much of the underlying genetic determinants still remain unknown. Our aim was to identify novel genetic variants that predispose to JIA.

Methods: We performed a genome-wide association study (GWAS) and replication in a total of 1166 JIA cases and 9500 unrelated controls of European ancestry.

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Background: Absence of the anterior (ACL) or posterior cruciate ligament (PCL) are rare congenital malformations that result in knee joint instability, with a prevalence of 1.7 per 100,000 live births and can be associated with other lower-limb abnormalities such as ACL agnesia and absence of the menisci of the knee. While a few cases of absence of ACL/PCL are reported in the literature, a number of large familial case series of related conditions such as ACL agnesia suggest a potential underlying monogenic etiology.

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The concept of atom-bond connectivity (ABC) index was introduced in the chemical graph theory in 1998. The atom-bond connectivity (ABC) index of a graph G defined as (see formula in text) where E(G) is the edge set and di is the degree of vertex v(i) of G. Very recently Graovac et al.

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Trinucleotide repeat instability underlies >20 human hereditary disorders. These diseases include many neurological and neurodegenerative situations, such as those caused by pathogenic polyglutamine (polyQ) domains encoded by expanded CAG repeats. Although mechanisms of instability have been intensely studied, our knowledge remains limited in part due to the lack of unbiased genome-wide screens in multicellular eukaryotes.

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Protein cleavage is a common feature in human neurodegenerative disease. Ataxin-3 protein with an expanded polyglutamine (polyQ) repeat causes spinocerebellar ataxia type-3 (SCA3), also called Machado-Joseph disease, and is cleaved in mammalian cells, transgenic mice and SCA3 patient brain tissue. However, the pathological significance of Ataxin-3 cleavage has not been carefully examined.

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Amyotrophic lateral sclerosis (ALS) is a motor neuron disease that leads to loss of motor function and early death. About 5% of cases are inherited, with the majority of identified linkages in the gene encoding copper, zinc-superoxide dismutase (SOD1). Strong evidence indicates that the SOD1 mutations confer dominant toxicity on the protein.

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The propensity of proteins to form beta-sheet-rich amyloid fibrils is related to a variety of biological phenomena, including a number of human neurodegenerative diseases and prions. A subset of amyloidogenic proteins forms amyloid fibrils through glutamine/asparagine (Q/N)-rich domains, such as pathogenic polyglutamine (poly(Q)) proteins involved in neurodegenerative disease, as well as yeast prions. In the former, the propensity of an expanded poly(Q) tract to abnormally fold confers toxicity on the respective protein, leading to neuronal dysfunction.

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Inherited mutations in PARK7, the gene encoding DJ-1, are associated with loss of protein function and early-onset parkinsonism. Like human DJ-1 (hDJ-1), Drosophila DJ-1b protects against oxidative insult and is modified with oxidation. We demonstrate that hDJ-1 rescues flies mutant for DJ-1b, and that a conserved cysteine residue in the fly protein (C104, analogous to C106 in hDJ-1) is critical for biological antioxidant function in vivo.

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Alpha-synuclein (alphaSyn) misfolding is associated with several devastating neurodegenerative disorders, including Parkinson's disease (PD). In yeast cells and in neurons alphaSyn accumulation is cytotoxic, but little is known about its normal function or pathobiology. The earliest defect following alphaSyn expression in yeast was a block in endoplasmic reticulum (ER)-to-Golgi vesicular trafficking.

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Arginine/lysine-rich motifs typically function as targeting signals for the translocation of proteins to the nucleus. Here, we demonstrate that such a motif consisting of four basic amino acids in the polyglutamine protein ataxin-3 (Atx-3) serves as a recognition site for the interaction with the molecular chaperone VCP. Through this interaction, VCP modulates the fibrillogenesis of pathogenic forms of Atx-3 in a concentration-dependent manner, with low concentrations of VCP stimulating fibrillogenesis and excess concentrations suppressing it.

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We have isolated a cDNA (GhWBC1) from cotton (Gossypium hirsutum) that encodes an ATP-binding cassette transporter of the WBC (white/brown complex) subfamily. Members of this subfamily are half-sized transporters and are reported to mediate lipid and drug excretion in human (Homo sapiens). GhWBC1 is highly expressed in developing fiber cells, but transcripts were also detectable in other tissues except roots.

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