PubMed Health⌕ Search

Biomedical subjects

Huiping Xu

Publications and source records attributed to Huiping Xu.

10 recordsLinked to original sources

Angiography-Based Index of Microcirculatory Resistance in Assessing the MVO and Infarct Size in STEMI Patients.

OBJECTIVES: To evaluate angiography-based index of microcirculatory resistance (angio-IMR) in assessing microvascular obstruction (MVO) and infarct size (IS) in ST-segment elevation myocardial infarction (STEMI). BACKGROUND: The effect of thrombolysis on post-percutaneous coronary intervention (PCI) angio-IMR, and its associations with MVO and IS remains unclear. METHODS: One hundred twenty-three STEMI patients randomized to receive 5&#x2009;mg intravenous bolus of recombinant staphylokinase (r-SAK) or normal saline (NS) before PCI were recruited. Angio-IMR was computed in infarct-related arteries. MVO and IS were detected by cardiac magnetic resonance imaging. RESULTS: Compared with NS group, r-SAK group exhibited numerically lower post-PCI angio-IMR (39.12 U vs. 42.57 U; p&#x2009;=&#x2009;0.567), MVO (54.0% vs. 70.9%; p&#x2009;=&#x2009;0.059), MVO extent (0.70% vs. 1.90%; p&#x2009;=&#x2009;0.101) and IS (21.30% vs. 24.50%; p&#x2009;=&#x2009;0.079). Post-PCI angio-IMR was positively correlated with MVO extent (&#x3c1;&#x2009;=&#x2009;0.347; p&#x2009;<&#x2009;0.001) and IS (&#x3c1;&#x2009;=&#x2009;0.324; p&#x2009;<&#x2009;0.001). Receiver operating characteristic analyses showed moderate diagnostic performance of angio-IMR for MVO (area under the curve [AUC] = 0.750; p&#x2009;<&#x2009;0.001), MVO&#x2009;>&#x2009;2.6% (AUC&#x2009;=&#x2009;0.735; p&#x2009;<&#x2009;0.001) and IS&#x2009;>&#x2009;25% (AUC&#x2009;=&#x2009;0.712; p&#x2009;<&#x2009;0.001). The exploratory optimal cut-off values for these endpoints were approximately 40&#x2009;U. CONCLUSIONS: In STEMI patients, a single bolus of r-SAK before PCI was associated with numeric reductions in post-PCI angio-IMR, MVO, MVO extent and IS. Additionally, angio-IMR exhibited a significantly positive correlation with both MVO extent and IS, demonstrating the diagnostic value of this wire-free method for assessing microvascular injury.

Humans↗

Metabolomics Reveals Metabolic Characteristics of Functional Cure in Chronic Hepatitis B Treated With Entecavir Combined With Pegylated Interferon Alpha.

BACKGROUND: Entecavir (ETV) combined with pegylated interferon alpha (PEG-IFN&#x3b1;) improves chronic hepatitis B (CHB) functional cure rates, but therapeutic heterogeneity and underlying metabolic mechanisms remain unclear. This study used untargeted metabolomics to identify metabolic signatures, mechanisms, and predictive biomarkers of functional cure with ETV-PEG-IFN&#x3b1;. METHODS: Thirty-eight CHB patients were grouped into ETV monotherapy (Group E, n = 12) and ETV-PEG-IFN&#x3b1; combination therapy (Group Z, n = 26); Group Z was subdivided into cured (Group A, n = 13) and noncured (Group B, n = 13). Serum metabolomic profiling, multivariate statistics, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis identified differential metabolites. A random forest model was built using key metabolites. RESULTS: Three hundred eighty-eight metabolites were identified. Four differential metabolites distinguished Group A and B (upregulated guanidinoacetic acid, uracil 5-carboxylate; downregulated L-methionine S-oxide, oleamide), enriching amino acid metabolism pathways. Nine differential metabolites between Group E and Z implicated amino acid, immune, and fatty acid pathways. The random forest model based on the four Group A/B metabolites showed 88.5% cross-validation accuracy (AUC = 0.920), with L-methionine S-oxide and oleamide as key predictors. CONCLUSIONS: This study reveals metabolic rewiring in CHB functional cure via ETV-PEG-IFN&#x3b1; therapy, involving energy metabolism, oxidative stress, and immunomodulation, based on which we propose a tentative metabolism-immunity synergy model to guide future research. Key metabolites, especially L-methionine S-oxide and oleamide, show exploratory predictive potential for functional cure that warrants further validation in independent cohorts.

Humans↗

Comparison of decanethiolate gold nanoparticles synthesized by one-phase and two-phase methods.

We investigated the differences between the decanethiolate gold nanoparticles synthesized by two different routes: one-phase and two-phase methods. Their properties were compared in bulk and at the air-water interface by transmission electron microscopy (TEM), X-ray reflectivity (XR), extended X-ray absorption fine structure (EXAFS) spectroscopy, X-ray powder diffraction (XRD), thermal gravimetric analysis (TGA), time-of-flight secondary-ion mass spectrometry (TOF-SIMS), electron paramagnetic resonance (EPR), and Langmuir-Blodgett technique. The mean nanoparticles sizes obtained by EXAFS and XRD were found to be smaller than those by the TEM measurements. We explained these differences by the structural disorder and multiple twinning in the nanoparticles. The one-phase particles were found by EXAFS to be smaller and had a higher grafting density of thiol chains than the two-phase particles. We attributed these differences to the enhanced disorder of the one-phase particles. At the air-water interface, the one-phase particles did not spread, while the two-phase particles spread and formed Langmuir films. TEM and XR results revealed that the close-packed monolayer of the two-phase particles collapsed and folded into multilayer films upon further compression.

Journal Article↗

A phase I/randomized phase II, non-comparative, multicenter, open label trial of CP-547,632 in combination with paclitaxel and carboplatin or paclitaxel and carboplatin alone as first-line treatment for advanced non-small cell lung cancer (NSCLC).

PURPOSE: To evaluate the toxicity profile and pharmacological properties of oral CP-547,632 alone and in combination with paclitaxel and carboplatin administered every 3 weeks, and to assess efficacy as measured by the objective response and progressive disease rates of oral CP-547,632 administered in combination with paclitaxel and carboplatin. PATIENTS AND METHODS: Patients with stage IIIB/IV or recurrent non-small cell lung cancer receiving first-line chemotherapy were treated with oral daily CP-547,632 in combination with paclitaxel 225 mg/m(2) and carboplatin AUC = 6 every 3 weeks. Pharmacokinetics parameters for CP-547,632 and paclitaxel were determined independently and during co-administration. RESULTS: Seventy patients were enrolled and 68 patients were treated, 37 in phase 1 and 31 in phase 2 (14 with the combination and 17 with chemotherapy alone). Dose-limiting toxicity of CP-547,632 250 mg by mouth daily in combination with paclitaxel and carboplatin was grade 3 rash and grade 3 diarrhea despite medical intervention. CP-547,632 did not significantly affect the pharmacologic profiles of paclitaxel and carboplatin. No subject had CR. In phase I, seven subjects (22.6%) had a confirmed partial response. In phase II, four subjects (28.6%) receiving CP-547,632 plus chemotherapy had a confirmed partial response. In the phase II chemotherapy alone group, four subjects (25%) had a confirmed partial response. CONCLUSION: The combination of CP-547,632 and paclitaxel and carboplatin was well-tolerated at doses up to 200 mg by mouth daily. Dose-limiting toxicity of CP-547,632 at 250 mg consisted of diarrhea and rash. CP-547,632 did not increase the objective response rate to chemotherapy alone in patients with advanced non-small cell lung cancer.

Administration, Oral↗

Metal core bonding motifs of monodisperse icosahedral Au13 and larger Au monolayer-protected clusters as revealed by X-ray absorption spectroscopy and transmission electron microscopy.

The atomic metal core structures of the subnanometer clusters Au13[PPh3]4[S(CH2)11CH3]2Cl2 (1) and Au13[PPh3]4[S(CH2)11CH3]4 (2) were characterized using advanced methods of electron microscopy and X-ray absorption spectroscopy. The number of gold atoms in the cores of these two clusters was determined quantitatively using high-angle annular dark field scanning transmission electron microscopy. Multiple-scattering-path analyses of extended X-ray absorption fine structure (EXAFS) spectra suggest that the Au metal cores of each of these complexes adopt an icosahedral structure with a relaxation of the icosahedral strain. Data from microscopy and spectroscopy studies extended to larger thiolate-protected gold clusters showing a broader distribution in nanoparticle core sizes (183 +/- 116 Au atoms) reveal a bulklike fcc structure. These results further support a model for the monolayer-protected clusters (MPCs) in which the thiolate ligands bond preferentially at 3-fold atomic sites on the nanoparticle surface, establishing an average composition for the MPC of Au180[S(CH2)11CH3]40. Results from EXAFS measurements of a gold(I) dodecanethiolate polymer are presented that offer an alternative explanation for observations in previous reports that were interpreted as indicating Au MPC structures consisting of a Au core, Au2S shell, and thiolate monolayer.

Journal Article↗

Arylisothiocyanato selective androgen receptor modulators (SARMs) for prostate cancer.

A new series of androgen receptor targeted agents (ARTA) was prepared and tested in androgen-dependent and -independent prostate cancer cell lines. These agents were bicalutamide analogs with isothiocyanato substituted B-rings. Also, the linker sulfone of R-bicalutamide was maintained or replaced with several alternative linkages including ether, amine, N-methylamine, thioether, and methylene (in this case the product was a racemic mixture) functional groups at the X-position. To expand the structure-activity relationship (SAR) of these arylisothiocyanato AR ligands, B-ring halogenated arylisothiocyanato ligands were also prepared and tested. The arylisothiocyanato AR ligands showed strong binding affinities to AR ranging from 0.6 to 54 nM. Among them, thioether and ether linkages demonstrated high binding affinities (0.6 and 4.6 nM, respectively) and selective cell growth inhibition (approximately 3- to 6-fold) for LNCaP, an androgen-dependent prostate cancer cell line, when compared to the androgen independent prostate cell lines (DU145, PC-3, and PPC-1) and a bladder cell line (TSU-Pr1). However, the ligands were inactive (IC50>100 mM) in a normal monkey kidney cell line (CV-1) that was used as the control for non-specific toxicity.

Animals↗

Sub-nanometer Au monolayer-protected clusters exhibiting molecule-like electronic behavior: quantitative high-angle annular dark-field scanning transmission electron microscopy and electrochemical characterization of clusters with precise atomic stoichiometry.

The synthesis and characterization of the clusters Au13[PPh3]4[S(CH2)11CH3]2Cl2 (1) and Au13[PPh3]4[S(CH2)11CH3]4 (2) are described. These mixed-ligand, sub-nanometer clusters, prepared via exchange of dodecanethiol onto phosphine-halide gold clusters, show enhanced stability relative to the parent. The characterization of these clusters features the precise determination of the number of gold atoms in the cluster cores using high-angle annular dark-field scanning transmission electron microscopy, allowing the assignment of 13 gold atoms (+/-3 atoms) to the composition of both cluster molecules. Electrochemical and optical measurements reveal discrete molecular orbital levels and apparent energy gaps of 1.6-1.7 eV for the two cluster molecules. The electrochemical measurements further indicate that the Au13[PPh3]4[S(CH2)11CH3]2Cl2 cluster undergoes an overall two-electron reduction. The electrochemical and spectroscopic properties of the two Au13 cluster molecules are compared with those of a secondary synthetic product, which proved to be larger Au thiolate-derivatized monolayer-protected clusters with an average core of Au180. The latter shows behavior fully consistent with the adoption of metallic-like properties.

Journal Article↗

Synthesis and biological evaluation of novel cytotoxic phospholipids for prostate cancer.

We describe herein synthesis, SAR, and biological evaluation of a novel series of cytotoxic serine amide phosphates (SAPs) for prostate cancer. These compounds were tested for their cytotoxicity in five human prostate cancer cell lines (DU-145, PC-3, LNCaP, PPC-1, and TSU), and in CHO and RH7777 cells (negative controls). Comparison of anticancer effects of these compounds with a standard chemotherapeutic agent 5-fluorouracil shows that they are very effective in killing prostate cancer cells with low micromolar cytotoxicity and provide us a new lead for the development of drugs for prostate cancer.

Animals↗

Pharmacology, pharmacokinetics, and metabolism of acetothiolutamide, a novel nonsteroidal agonist for the androgen receptor.

The present study characterized the in vitro androgen receptor (AR) binding affinity, in vitro and in vivo pharmacological activity, and in vivo pharmacokinetics and metabolism of acetothiolutamide, a nonsteroidal AR ligand. AR binding was determined by a competitive binding assay. In vitro AR agonist activity was examined by a cotransfection assay. Acetothiolutamide displayed high AR binding affinity (K(i) = 4.9 +/- 0.2 nM) and full agonist activity in the in vitro studies. Next, the androgenic, anabolic, and antiandrogenic activity of acetothiolutamide was evaluated in a castrated immature rat model. In this animal model, acetothiolutamide exhibited an overall negligible androgenic effect, but a statistically significant anabolic effect at high subcutaneous doses. Also, acetothiolutamide demonstrated a noticeable antiandrogenic effect in castrated rats supplemented with testosterone propionate. To understand the causes for the observed disparity between in vitro and in vivo activities, pharmacokinetics and metabolism of acetothiolutamide were studied in male Sprague-Dawley rats. Acetothiolutamide was rapidly cleared from rat plasma (clearance of about 45 ml/min/kg) in a concentration-independent manner after i.v. dosing. Acetothiolutamide was completely absorbed after subcutaneous administration, but not bioavailable after oral dose. In the metabolism study, the unchanged molecule and its metabolites in urine and fecal samples were detected by high-performance liquid chromatography-mass spectrometry. The structures of major metabolites were elucidated with liquid chromatography-tandem mass spectrometry. After i.v. administration, acetothiolutamide was excreted in urine and feces as unchanged drug and a variety of metabolites. Oxidation, hydrolysis, and sulfate conjugation of phase I metabolites were the major metabolic pathways of acetothiolutamide in rats. Overall, the high plasma clearance of acetothiolutamide, due to its extensive hepatic metabolism, likely contributed to its lack of androgenic activity in vivo.

Androgens↗

Pharmacodynamics of selective androgen receptor modulators.

The present study aimed to identify selective androgen receptor modulators (SARMs) with in vivo pharmacological activity. We examined the in vitro and in vivo pharmacological activity of four chiral, nonsteroidal SARMs synthesized in our laboratories. In the in vitro assays, these compounds demonstrated moderate to high androgen receptor (AR) binding affinity, with K(i) values ranging from 4 to 37 nM, and three of the compounds efficaciously stimulated AR-mediated reporter gene expression. The compounds were then administered subcutaneously to castrated rats to appraise their in vivo pharmacological activity. Androgenic activity was evaluated by the ability of these compounds to maintain the weights of prostate and seminal vesicle, whereas levator ani muscle weight was used as a measure of anabolic activity. The maximal response (E(max)) and dose for half-maximal effect (ED(50)) were determined for each compound and compared with that observed for testosterone propionate (TP). Compounds S-1 and S-4 demonstrated in vivo androgenic and anabolic activity, whereas compounds S-2 and S-3 did not. The activities of S-1 and S-4 were tissue-selective in that both compounds stimulated the anabolic organs more than the androgenic organs. These two compounds were less potent and efficacious than TP in androgenic activity, but their anabolic activity was similar to or greater than that of TP. Neither S-1 nor S-4 caused significant luteinizing hormone or follicle stimulating hormone suppression at doses near the ED(50) value. Thus, compounds S-1 and S-4 were identified as SARMs with potent and tissue-selective in vivo pharmacological activity, and represent the first members of a new class of SARMs with selective anabolic effects.

Anilides↗