Publications by authors named "Yuwang Liu"

The current regulatory path for new drug registration in East Asian countries has led to significant delay of the new medicines in these countries. A unified regulatory path and allowance of mutual usage of clinical data in East Asian countries would lead to cost saving in drug development and expedite the new drug registration in these countries. The objectives of the present analysis are to compare the approval dates of a selection of products developed by Pfizer in the United States and East Asian countries (China, Japan, Korea) and compare the pharmacokinetics and recommended doses of these products in East Asian countries.

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This paper introduces a novel high-certainty visual servo algorithm for a space manipulator with flexible joints, which consists of a kinematic motion planner and a Lyapunov dynamics model reference adaptive controller. To enhance kinematic certainty, a three-stage motion planner is proposed in Cartesian space to control the intermediate states and minimize the relative position error between the manipulator and the target. Moreover, a planner in joint space based on the fast gradient descent algorithm is proposed to optimize the joint's deviation from the centrality.

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Azithromycin (Zithromax) is an azalide antibiotic that binds to the 50S ribosomal subunit of the susceptible organism and thereby interferes with its protein synthesis. An open-label, randomized, single-dose, 3-way crossover bioequivalence study was conducted to compare the rate and extent of absorption of the azithromycin 250-mg tablet manufactured at Pfizer Dalian (China) and that at Pfizer Barceloneta (United States) under fasted and fed conditions in healthy Chinese subjects. This study aimed to support a generic consistency evaluation program, initiated by the National Medical Products Administration, for evaluating the quality and efficacy of the products manufactured in China.

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Acarbose and metformin have been recommended both as monotherapy and add-on therapy in type 2 diabetes mellitus. A novel fixed-dose combination (FDC) of acarbose and metformin has been developed to improve compliance and patient adherence to therapy. The current study investigated the bioequivalence (BE) between acarbose/metformin FDC (50 mg/500 mg) with corresponding loose combination of individual components under fasting conditions in healthy Chinese male and female subjects, using a randomized, 2-period, 2-way crossover study design.

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Space capture actuators face problems such as insufficient flexibility and electrical components that are vulnerable to extreme space environments. To address these problems, a centralized-driven flexible continuous robot based on a multiple scissor mechanism units is proposed in this study. The continuous robot body is composed of two scissor mechanism units coupled in series, and the base container's three motors to drive the robot.

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Objective: To investigate the bioequivalence, safety, and tolerability of single-dose nifedipine gastrointestinal therapeutic system (GITS) and candesartan as a fixed-dose combination (FDC) relative to the loose combination in healthy males under fed conditions.

Materials And Methods: A total of 48 subjects received nifedipine GITS 60 mg and candesartan 32 mg as an FDC or loose combination in an open-label, 2-way crossover, 2-treatment sequence design, with a washout of at least 5 days between treatments. Study medications were administered following an overnight fast of at least 10 hours, and 30 minutes after ingestion of a high-fat test meal.

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We propose a new highly reliable and lightweight embedded optical torque sensor for biomimetic robot arm enabling the torque measurement in joints, which can measure torque of the joint by detecting torsion of its elastic element (mechanical structure or flexure element). Flexure spring is introduced as the elastic element of the torque sensor in this paper. Because of its curve modeling, flexure spring is not inclined to be broken contrast to crossbeam structure, which is commonly used in torque sensor.

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The Notch signalling pathway mediates cell fate decisions and is tumour suppressive or oncogenic depending on the context. During lung development, Notch pathway activation inhibits the differentiation of precursor cells to a neuroendocrine fate. In small-cell lung cancer, an aggressive neuroendocrine lung cancer, loss-of-function mutations in NOTCH genes and the inhibitory effects of ectopic Notch activation indicate that Notch signalling is tumour suppressive.

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Objective: To investigate the pharmacokinetic (PK) profiles and safety of nifedipine and candesartan after a single oral dose of nifedipine gastrointestinal therapeutic system (GITS) 30 mg/candesartan cilexetil 8 mg (N30/C8 mg) fixed-dose combination (FDC) in adults with mild to moderate hepatic impairment.

Methods: A phase I, single-center, non-randomized, non-controlled, non-blinded, observational study (N = 32). PK profiles for nifedipine and candesartan were assessed in patients with mild (Child-Pugh A; group 1) or moderate (Child-Pugh B; group 2) hepatic impairment and compared with age- and gender-matched healthy controls (groups 3 and 4) following a single dose of N30/C8 FDC.

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The objectives of the study were to assess the safety and pharmacokinetics of silodosin capsules in 82 healthy male Chinese subjects. To evaluate the safety after single-dosing escalation, 40 subjects were equally divided into 4 groups (2, 4, 8, 12 mg) by a randomized, double-blind and placebo-controlled design. To assess the pharmacokinetics after single-dosing, 30 subjects were equally divided into 3 groups (4, 8, 12 mg).

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Protective effect of valsartan (Val), an angiotensin II (AII)-receptor blocker (ARB), against organ damage is reported to depend on the dosing time in hypertensive patients. Dosing-time-dependent effect of Val on survival of stroke-prone spontaneously hypertensive rats (SHRSP) under a 12-h lighting cycle was examined. Val (4 mg/kg per day) and olmesartan medoxomil (OM) (1 mg/kg per day), another ARB with a slower dissociation from the AII receptor, were given once daily at 2, 8, 14, or 20 HALO (hours after lights on).

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Protective effect of valsartan (Val), an angiotensin II (AII)-receptor blocker (ARB), against organ damage is reported to depend on the dosing time in hypertensive patients. Dosing-time-dependent effect of Val on survival of stroke-prone spontaneously hypertensive rats (SHRSP) under a 12-h lighting cycle was examined. Val (4 mg/kg per day) and olmesartan medoxomil (OM) (1 mg/kg per day), another ARB with a slower dissociation from the AII receptor, were given once daily at 2, 8, 14, or 20 HALO (hours after lights on).

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Hypertensive patients have an increasing risk of osteoporosis. A recent case-controlled study has demonstrated that anti-hypertensive therapy reduced a risk of fracture in these patients. In this study, we investigated whether amlodipine protects against the reduction in bone density in stroke-prone spontaneously hypertensive rats (SHR-sp).

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A rapid, sensitive and specific liquid chromatography-tandem mass spectrometric (LC-MS/MS) method has been developed and validated for the determination of silodosin in human plasma. Silodosin and internal standard (IS) were extracted from human plasma by liquid-liquid extraction using methyl t-butyl ether and analyzed on an Agilent C(8) column with the mobile phase of acetonitrile-10 mM ammonium acetate (40:60, v/v) adjusted to pH 4.5 with acetic acid.

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Aims: To investigate the safety, pharmacokinetics and pharmacodynamics of rivaroxaban, an oral, direct Factor Xa (FXa) inhibitor, in healthy, male Chinese subjects.

Methods: Two randomized, single-blind, placebo-controlled, dose-escalation studies were conducted in healthy Chinese men aged 18-45 years. In the single-dose study, subjects received single, oral doses of rivaroxaban 2.

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Pancreatic cancer is one of the deadliest forms of cancer and effective treatment remains a clinical challenge. Transforming growth factor-beta (TGF-beta) has important roles in primary tumor progression and in promoting metastasis, and has become an attractive target for therapy. Previously, we reported that treatment of pancreatic cancer cells in vitro with SD-208, a small molecule inhibitor of the TGF-beta receptor I kinase (TGF-betaRI), inhibited expression of genes associated with tumor progression and inhibited invasiveness in a cell-based assay.

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The effects of small-molecule p38 inhibitors in numerous models of different disease states have been published, including those of SD-282, an indole-5-carboxamide inhibitor. The aim of the present study was to evaluate the pharmacological activity of SD-282 on cytokine production in vitro as well as in 2 in vivo models of inflammation in order to illuminate the role of this particular inhibitor in diverse disease states. The results presented here provide further characterization of SD-282 and provide a context in which to interpret the activity of this p38 inhibitor in models of arthritis, pain, myocardial injury, sepsis and asthma; all of which have an inflammatory component.

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Transforming growth factor-beta (TGFbeta) is a major mediator of normal wound healing and of pathological conditions involving fibrosis, such as idiopathic pulmonary fibrosis. TGFbeta also stimulates the differentiation of myofibroblasts, a hallmark of fibrotic diseases. In this study, we examined the underlying processes of TGFbetaRI kinase activity in myofibroblast conversion of human lung fibroblasts using specific inhibitors of TGFbetaRI (SD-208) and p38 mitogen-activated kinase (SD-282).

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Mitogen-activated protein kinases (MAPKs) and heat shock proteins (HSPs) are ubiquitous proteins that function within T cells in both normal and stress-related pathophysiological states, including type 1 diabetes. The nonobese diabetic (NOD) mouse spontaneously develops T cell-mediated autoimmune pancreatic beta cell destruction that is similar to type 1 diabetes in humans. Because p38 MAPKs have been shown to modulate T cell function, we studied the effects of a p38alpha MAPK-selective inhibitor, indole-5-carboxamide (SD-169), on the development and progression of type 1 diabetes in the NOD mouse.

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The cytokine transforming growth factor (TGF)-beta, by virtue of its immunosuppressive and promigratory properties, has become a major target for the experimental treatment of human malignant gliomas. Here we characterize the effects of a novel TGF-beta receptor (TGF-betaR) I kinase inhibitor, SD-208, on the growth and immunogenicity of murine SMA-560 and human LN-308 glioma cells in vitro and the growth of and immune response to intracranial SMA-560 gliomas in syngeneic VM/Dk mice in vivo. SD-208 inhibits the growth inhibition of TGF-beta-sensitive CCL64 cells mediated by recombinant TGF-beta1 or TGF-beta2 or of TGF-beta-containing glioma cell supernatant at an EC(50) of 0.

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Amyloid beta peptide (Abeta) generated from amyloid precursor protein (APP) is central to Alzheimer's disease (AD). Signaling pathways affecting APP amyloidogenesis play critical roles in AD pathogenesis and can be exploited for therapeutic intervention. Here, we show that sumoylation, covalent modification of cellular proteins by small ubiquitin-like modifier (SUMO) proteins, regulates Abeta generation.

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