Publications by authors named "Yonghong Bai"

DNA double-strand breaks occur in all human cells on a daily basis and must be repaired with high fidelity to minimize genomic instability. Deficiencies in high-fidelity DNA repair by homologous recombination lead to dependence on DNA polymerase theta, which identifies DNA microhomologies in 3' single-stranded DNA overhangs and anneals them to initiate error-prone double-strand break repair. The resulting genomic instability is associated with numerous cancers, thereby making this polymerase an attractive therapeutic target.

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Transient receptor potential canonical (TRPC) proteins form nonselective cation channels that play physiological roles in a wide variety of cells. Despite growing evidence supporting the therapeutic potential of TRPC6 inhibition in treating pathological cardiac and renal conditions, mechanistic understanding of TRPC6 function and modulation remains obscure. Here we report cryo-EM structures of TRPC6 in both antagonist-bound and agonist-bound states.

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Doppler echocardiography (D-ECHO) is a commonly used imaging tool for both diagnosis and follow-up examination of congenital heart disease (CHD). The goal of this study is to evaluate the accuracy of D-ECHO as used to measure an estimate sPAP in pediatric patients with CHD. A prospective study in 397 pediatric patients with CHD has been carried out to compare estimate sPAP measured with D-ECHO to that measured with right heart catheterization (RHC).

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Trastuzumab and pertuzumab are monoclonal antibodies that bind to distinct subdomains of the extracellular domain of human epidermal growth factor receptor 2 (HER2). Adding these monoclonal antibodies to the treatment regimen of HER2-positive breast cancer has changed the paradigm for treatment in that form of cancer. Synergistic activity has been observed with the combination of these two antibodies leading to hypotheses regarding the mechanism(s) and to the development of bispecific antibodies to maximize the clinical effect further.

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Stearoyl-CoA desaturase (SCD) is conserved in all eukaryotes and introduces the first double bond into saturated fatty acyl-CoAs. Because the monounsaturated products of SCD are key precursors of membrane phospholipids, cholesterol esters and triglycerides, SCD is pivotal in fatty acid metabolism. Humans have two SCD homologues (SCD1 and SCD5), while mice have four (SCD1-SCD4).

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Membrane-embedded prenyltransferases from the UbiA family catalyze the Mg2+-dependent transfer of a hydrophobic polyprenyl chain onto a variety of acceptor molecules and are involved in the synthesis of molecules that mediate electron transport, including Vitamin K and Coenzyme Q. In humans, missense mutations to the protein UbiA prenyltransferase domain-containing 1 (UBIAD1) are responsible for Schnyder crystalline corneal dystrophy, which is a genetic disease that causes blindness. Mechanistic understanding of this family of enzymes has been hampered by a lack of three-dimensional structures.

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Previous cysteine scanning studies of the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel have identified several transmembrane segments (TMs), including TM1, 3, 6, 9, and 12, as structural components of the pore. Some of these TMs such as TM6 and 12 may also be involved in gating conformational changes. However, recent results on TM1 seem puzzling in that the observed reactive pattern was quite different from those seen with TM6 and 12.

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Cystic fibrosis transmembrane conductance regulator (CFTR) is a member of the ATP-binding cassette (ABC) transporter superfamily, but little is known about how this ion channel that harbors an uninterrupted ion permeation pathway evolves from a transporter that works by alternately exposing its substrate conduit to the two sides of the membrane. Here, we assessed reactivity of intracellularly applied thiol-specific probes with cysteine residues substituted into the 12th transmembrane segment (TM12) of CFTR. Our experimental data showing high reaction rates of substituted cysteines toward the probes, strong blocker protection of cysteines against reaction, and reaction-induced alterations in channel conductance support the idea that TM12 of CFTR contributes to the lining of the ion permeation pathway.

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Cystic fibrosis transmembrane conductance regulator (CFTR) is the only member of the adenosine triphosphate-binding cassette (ABC) transporter superfamily that functions as a chloride channel. Previous work has suggested that the external side of the sixth transmembrane segment (TM6) plays an important role in governing chloride permeation, but the function of the internal side remains relatively obscure. Here, on a cysless background, we performed cysteine-scanning mutagenesis and modification to screen the entire TM6 with intracellularly applied thiol-specific methanethiosulfonate reagents.

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Objective: To explore mutation of Cited2 gene coding strand in Chinese patients with congenital heart disease (CHD).

Methods: DNA was extracted from the blood samples of 120 nonhomologous and various CHD patients and 100 healthy children. The sequence of coding regions of Cited2 was amplified by PCR and compared to those in the GeneBank after sequencing to identify the mutations.

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Objective: Endocardial fibroelastosis (EFE), a common pediatric cardiovascular disease, often results in chronic heart failure (CHF) and death. Clinical trials have shown that the regimen of combining beta-adrenoreceptor blocker with traditional medicines against CHF can improve left ventricular function and prevent the ventricle from remodeling in patients with CHF. The present study aimed to observe the effect of carvedilol on concentration of plasma brain-type natriuretic peptide (BNP), and safety in children with EFE.

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