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PTEN: an emerging target in rheumatoid arthritis? Cell Commun Signal 2024; 22:246. [PMID: 38671436 PMCID: PMC11046879 DOI: 10.1186/s12964-024-01618-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Accepted: 04/17/2024] [Indexed: 04/28/2024] Open
Abstract
Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a critical tumor suppressor protein that regulates various biological processes such as cell proliferation, apoptosis, and inflammatory responses by controlling the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PI3K/AKT) signaling pathway. PTEN plays a crucial role in the pathogenesis of rheumatoid arthritis (RA). Loss of PTEN may contribute to survival, proliferation, and pro-inflammatory cytokine release of fibroblast-like synoviocytes (FLS). Also, persistent PI3K signaling increases myeloid cells' osteoclastic potential, enhancing localized bone destruction. Recent studies have shown that the expression of PTEN protein in the synovial lining of RA patients with aggressive FLS is minimal. Experimental upregulation of PTEN protein expression could reduce the damage caused by RA. Nonetheless, a complete comprehension of aberrant PTEN drives RA progression and its interactions with other crucial molecules remains elusive. This review is dedicated to promoting a thorough understanding of the signaling mechanisms of aberrant PTEN in RA and aims to furnish pertinent theoretical support for forthcoming endeavors in both basic and clinical research within this domain.
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Multifunctional Applications of Ionic Liquids in Polymer Materials: A Brief Review. Molecules 2023; 28:molecules28093836. [PMID: 37175245 PMCID: PMC10180292 DOI: 10.3390/molecules28093836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 04/25/2023] [Accepted: 04/28/2023] [Indexed: 05/15/2023] Open
Abstract
As a new generation of green media and functional materials, ionic liquids (ILs) have been extensively investigated in scientific and industrial communities, which have found numerous ap-plications in polymeric materials. On the one hand, much of the research has determined that ILs can be applied to modify polymers which use nanofillers such as carbon black, silica, graphene oxide, multi-walled carbon nanotubes, etc., toward the fabrication of high-performance polymer composites. On the other hand, ILs were extensively reported to be utilized to fabricate polymeric materials with improved thermal stability, thermal and electrical conductivity, etc. Despite substantial progress in these areas, summary and discussion of state-of-the-art functionalities and underlying mechanisms of ILs are still inadequate. In this review, a comprehensive introduction of various fillers modified by ILs precedes a systematic summary of the multifunctional applications of ILs in polymeric materials, emphasizing the effect on vulcanization, thermal stability, electrical and thermal conductivity, selective permeability, electromagnetic shielding, piezoresistive sensitivity and electrochemical activity. Overall, this review in this area is intended to provide a fundamental understanding of ILs within a polymer context based on advantages and disadvantages, to help researchers expand ideas on the promising applications of ILs in polymer fabrication with enormous potential.
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Systematic investigation on the effect of processing procedures on the performance of oil‐resistant thermoplastic vulcanizates based on
HNBR
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TPEE. J Appl Polym Sci 2023. [DOI: 10.1002/app.53860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
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4
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Combining multiple hydrogen bonds and boronic ester chemistry towards mechanically robust and creep resisting elastomer vitrimer. POLYMER 2023. [DOI: 10.1016/j.polymer.2022.125595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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5
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Thermoplastic vulcanizates with an integration of good mechanical performance and excellent resistance to high temperature and oil based on
HNBR
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TPEE. POLYM ADVAN TECHNOL 2022. [DOI: 10.1002/pat.5958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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6
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The Safety, Toleration, and Pharmacokinetics of Two Intravenous Voriconazole Formulations in Healthy Chinese Volunteers After Increasing Dose Administrations. Clin Pharmacol Drug Dev 2022; 11:1211-1220. [PMID: 35711147 DOI: 10.1002/cpdd.1126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 05/15/2022] [Indexed: 01/27/2023]
Abstract
Sulfobutyl ether-beta-cyclodextrin sodium salt contained in the marketed intravenous voriconazole injection as a solubilizer may cause harmful accumulations. This study aimed to evaluate the safety, tolerability, and pharmacokinetics (PKs) of two intravenous voriconazole formulations containing excipients from different manufacturers using increasing dose administrations in healthy Chinese volunteers. A randomized, double-blind, placebo-controlled trial was conducted in three cohorts with 42 healthy Chinese volunteers. Each cohort of 14 volunteers was allocated in proportion (8:4:2) to test the formulation, reference voriconazole, or placebo successively by single-dose then multiple-dose administrations of 3, 4, and 6 mg/kg. Forty-one volunteers completed all drug administrations. The pharmacokinetics of test formulations are characterized by high interindividual variability (coefficient of variance of Cmax up to 68.0%, AUC0-τ up to 70.2%, and nonlinear PKs with a regression coefficient of Cmax = 1.31 and AUC0-τ = 1.75 in a single dose). In the steady state, RAuc of the test drug versus reference drug of the 3, 4, and 6 mg/kg dose group were 5.2 and 5.3, 5.6 and 6.3, and 5.8 and 5.5, respectively, and Rcmax were 2.5 and 2.7, 2.6 and 3.1, and 2.8 and 2.6, respectively. Eighty-three adverse events with 37 transient visual disturbances were mild. PKs with high interindividual variability, nonlinear characteristics, and significant dose-dependent accumulation were comparable between the two formulations. Overall, the safety of the test formulation was acceptable.
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Influence of the Synergistic Effect of Multi-Walled Carbon Nanotubes and Carbon Fibers in the Rubber Matrix on the Friction and Wear of Metals during the Mixing Process. Polymers (Basel) 2022; 14:polym14183731. [PMID: 36145877 PMCID: PMC9502179 DOI: 10.3390/polym14183731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 09/02/2022] [Accepted: 09/05/2022] [Indexed: 11/16/2022] Open
Abstract
As a piece of high-intensity running equipment, the wear of an internal mixer determines the quality of rubber and its life. In general, the wear of an internal mixer is caused by the friction between the rubber and metal during the mixing process, and the most severe wear position is the end face of the equipment. In this paper, a mixture of multi-walled carbon nanotubes (MWCNTs) and carbon fibers (CFs) are added to rubber by mechanical compounding to obtain MWCNT/CF/carbon black (CB) composites. By investigating the synergistic mechanism of MWCNTs and CFs, we analyze the effect of the MWCNT/CF ratio on the frictional wear of metal on the end face of the internal mixer. At the microscopic level, MWCNTs and CFs form a spatial meshwork with CB particles through synergistic interactions. The CB particles can be adsorbed on the spatial meshwork to promote the dispersion of CB particles. In addition, the formation of oil film can be slowed down due to the spatial meshwork, which could hinder the spillage of aromatic oil. Meanwhile, the spatial meshwork serves as a physical isolation layer between the rubber and metal to reduce friction. Therefore, it dramatically impacts the dispersion degree of CB particles, the friction coefficient, the roughness of the surface, and the wear of metal. It shows that the synergistic effect of MWCNT/CF and CB particles is best when the CF content of the rubber matrix is 5 phr, showing the most stable spatial network structure, the best dispersion of CB particles, and minor wear on the end face of the internal mixer.
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Damping and Electromechanical Behavior of Ionic-Modified Brominated Poly(isobutylene-co-isoprene) Rubber Containing Petroleum Resin C5. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.1c04790] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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9
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Molecularly engineered dual-crosslinked elastomer vitrimers with superior strength, improved creep resistance, and retained malleability. Polym Chem 2022. [DOI: 10.1039/d2py00489e] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Preparation of covalently crosslinked elastomers with an integration of high mechanical performance, enhanced creep resistance and retained malleability by incorporating quadruple hydrogen bonds into dynamic boronic ester bonds crosslinked SBR.
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Systematic Analysis of the Global, Regional and National Burden of Cardiovascular Diseases from 1990 to 2017. J Epidemiol Glob Health 2021; 12:92-103. [PMID: 34902116 PMCID: PMC8907368 DOI: 10.1007/s44197-021-00024-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 11/30/2021] [Indexed: 12/11/2022] Open
Abstract
Background Previous studies on the burden of cardiovascular diseases (CVDs) were mainly based on limited data of the study period or area, or did not include detailed risk factor analysis. Objective To investigate up-to-date temporal and regional trends and risk factors of mortality and disability-adjusted life years (DALYs) attributed to CVDs by age, sex, and disease throughout the world. Methods Data for the disease burden of CVDs in 195 countries and territories from 1990 to 2017, including mortality, DALYs, age-standardized mortality rates, and age-standardized DALY rates, were estimated from the Global Burden of Disease Study 2017. Risk factors attributable to deaths and DALYs for CVDs were also estimated using the comparative risk assessment framework. Results The number of deaths from CVDs increased by 48.62%, from 11.94 (95% UI 11.78–12.18) million in 1990 to 17.79 (17.53–18.04) million in 2017. However, the age-standardized mortality rate decreased by an average of − 1.45% (− 1.72% to − 1.18%) annually. After fluctuation in the expected age-standardized mortality rate of CVDs in most of the socio-demographic index (SDI) scale, these rates decrease rapidly for SDI values of 0.7 and higher. In 2017, metabolic risks accounted for 73.48% of deaths and 73.25% of DALYs due to CVDs, behavioral factors accounted for 63.23% of deaths and 66.71% of attributable DALYs. Conclusion CVDs remain a major global health burden due to the increment in death numbers and DALYs. Aging and the main risk factors are the main drivers of mortality and health loss. More attention to main risk factors should be paid with supportive health policies. Supplementary Information The online version contains supplementary material available at 10.1007/s44197-021-00024-2.
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Lightweight and flexible silicone rubber foam with dopamine grafted multi-walled carbon nanotubes and silver nanoparticles using supercritical foaming technology: Its preparation and electromagnetic interference shielding performance. Eur Polym J 2021. [DOI: 10.1016/j.eurpolymj.2021.110839] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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12
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Application of a Cloud Video Conference Method for Recruiting Healthy Subjects Into an Early-Phase Clinical Trial During the COVID-19 Pandemic. Front Public Health 2021; 9:657804. [PMID: 34490177 PMCID: PMC8416603 DOI: 10.3389/fpubh.2021.657804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Accepted: 06/21/2021] [Indexed: 11/26/2022] Open
Abstract
Objective: Our objective is to explore the effect of applying cloud video conferencing methods to the informed consent process in an early-phase clinical trial during the COVID-19 pandemic. Methods: All participants who intended to participate in the trial were informed via a cloud video conference before signing the informed consent forms (ICF). Then, the attitudes of the participants with the cloud video conference and their understanding of the trial were evaluated using a questionnaire when they visited to sign the ICF onsite. Results: A total of 165 subjects participated in the cloud video conference process, and 142 visited the site to sign and date the ICFs at the center during the appointment time. The survey showed that nearly 100% of the subjects evaluated the video-based informed consent process as very good or good and gave correct answers to questions about the trial. Furthermore, 136 (95.8%) subjects believed that the knowledge about the trial derived via the video-based informed consent process was consistent with the onsite reality, and 139 (97.9%) subjects expressed their willingness to participate in an informed consent procedure undertaken through an online video conference. Conclusions: The video-based informed consent process achieved the same effects as an onsite informed consent process. The former saves time and cost of transportation for the subject and exhibits good public acceptance; especially in light of the COVID-19 pandemic, this process is conducive for reducing the risk of subject infection due to travel and would also help avoid crowding on site.
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A Structural Equation Model of Health-Related Quality of Life in Chinese Patients With Rheumatoid Arthritis. Front Psychiatry 2021; 12:716996. [PMID: 34421688 PMCID: PMC8371236 DOI: 10.3389/fpsyt.2021.716996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Accepted: 07/13/2021] [Indexed: 11/13/2022] Open
Abstract
Background: The aim of this study was to examine how body image, Disease Activity Score in 28 joints, the feeling of being anxious, depression, fatigue, quality of sleep, and pain influence the quality of life (QoL) in patients with rheumatoid arthritis (RA). Methods: A multicenter cross-sectional survey with convenience sampling was conducted from March 2019 and December 2019, 603 patients with RA from five hospitals were evaluated using the Body Image Disturbance Questionnaire, Disease Activity Score in 28 joints, Hospital Anxiety and Depression Scale, Fatigue Severity Scale, Pittsburgh Sleep Quality Index, Short Form 36 Health Survey, and Global Pain Scale. The relationship between quality of life and other variables was evaluated by using the structural equation model (SEM). Results: A total of 580 patients were recruited. SEM fitted the data very well with a root mean square error of approximation (RMSEA) of 0.072. Comparative fit index of 0.966, and Tucker-Lewis index of 0.936. The symptoms and the normalized factor load of six variables showed that the normalized factor load of pain was 0.99. Conclusions: The QoL model was used to fit an SEM to systematically verify and analyze the population disease data, biological factors, and the direct and indirect effects of the symptom group on the QoL, and the interactions between the symptoms. Therefore, the diagnosis, treatment and rehabilitation of RA is a long-term, dynamic, and complex practical process. Patients' personal symptoms, needs, and experiences also vary greatly. Comprehensive assessment of patients' symptoms, needs, and experiences, as well as the role of social support cannot be ignored, which can help to meet patients' nursing needs, improve their mood and pain-based symptom management, and ultimately improve patients' QoL.
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How to safely and smoothly resume trials after the COVID-19 outbreak. J Glob Health 2020; 10:020310. [PMID: 33110514 PMCID: PMC7535132 DOI: 10.7189/jogh.10.020310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Rapid Nanowelding of Carbon Coatings onto Glass Fibers by Electrothermal Shock. ACS APPLIED MATERIALS & INTERFACES 2020; 12:37722-37731. [PMID: 32814412 DOI: 10.1021/acsami.0c09549] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
With the rapid development of nanomanufacturing, scaling up of nanomaterials requires advanced manufacturing technology to composite nanomaterials with disparate materials (ceramics, metals, and polymers) to achieve hybrid properties and coupling performances for practical applications. Attempts to assemble nanomaterials onto macroscopic materials are often accompanied by the loss of exceptional nanoscale properties during the fabrication process, which is mainly due to the poor contacts between carbon nanomaterials and macroscopic bulk materials. In this work, we proposed a novel cross-scale manufacturing concept to process disparate materials in different length scales and successfully demonstrated an electrothermal shock approach to process the nanoscale material (e.g., carbon nanotubes) and macroscale (e.g., glass fiber) with good bonding and excellent mechanical property for emerging applications. The excellent performance and potentially lower cost of the electrothermal shock technology offers a continuous, ultrafast, energy-efficient, and roll-to-roll process as a promising heating solution for cross-scale manufacturing.
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Clinical characteristics of COVID-19 in patients with preexisting ILD: A retrospective study in a single center in Wuhan, China. J Med Virol 2020; 92:2742-2750. [PMID: 32533777 PMCID: PMC7322991 DOI: 10.1002/jmv.26174] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Accepted: 06/08/2020] [Indexed: 01/04/2023]
Abstract
Since the outbreak of 2019 novel coronavirus (SARS‐CoV‐2) pneumonia, many patients with underlying disease, such as interstitial lung disease (ILD), were admitted to Tongji hospital in Wuhan, China. To date, no data have ever been reported to reflect the clinical features of Corona Virus Disease 2019 (COVID‐19) among these patients with preexisting ILD. We analyzed the incidence and severity of COVID‐19 patients with ILD among 3201 COVID‐19 inpatients, and compared two independent cohorts of COVID‐19 patients with pre‐existing ILD (n = 28) and non‐ILD COVID‐19 patients (n = 130). Among those 3201 COVID‐19 inpatients, 28 of whom were COVID‐19 with ILD (0.88%). Fever was the predominant symptom both in COVID‐19 with ILD (81.54%) and non‐ILD COVID‐19 patients (72.22%). However, COVID‐19 patients with ILD were more likely to have cough, sputum, fatigue, dyspnea, and diarrhea. A very significantly higher number of neutrophils, monocytes, interleukin (IL)‐8, IL‐10, IL‐1β, and D‐Dimer was characterized in COVID‐19 with ILD as compared to those of non‐ILD COVID‐19 patients. Furthermore, logistic regression models showed neutrophils counts, proinflammatory cytokines (tumor necrosis factor‐alpha, IL6, IL1β, IL2R), and coagulation dysfunction biomarkers (D‐Dimer, PT, Fbg) were significantly associated with the poor clinical outcomes of COVID‐19. ILD patients could be less vulnerable to SARS‐CoV‐2. However, ILD patients tend to severity condition after being infected with SARS‐CoV‐2. The prognosis of COVID‐19 patients with per‐existing ILD is significantly worse than that of non‐ILD patients. And more, aggravated inflammatory responses and coagulation dysfunction appear to be the critical mechanisms in the COVID‐19 patients with ILD. ILD patients could be less vulnerable to SARS‐CoV‐2. However, ILD patients tend to severity condition after being infected with SARS‐CoV‐2. The prognosis of COVID‐19 patients with per‐existing ILD is significantly worse than that of non‐ILD patients. And more, aggravated inflammatory responses and coagulation dysfunction appear to be the critical mechanisms in the COVID‐19 patients with ILD.
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913 A variant of Mohs micrographic surgery: The muffin technique. J Invest Dermatol 2020. [DOI: 10.1016/j.jid.2020.03.929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Pharmacokinetics, Safety, and Bioequivalence of Two Empagliflozin Formulations after Single Oral Administration under Fasting and Fed Conditions in Healthy Chinese Subjects: An Open-label Randomized Single-dose Two-sequence, Two-treatment, Two-period Crossover Study. Pharmacotherapy 2020; 40:623-631. [PMID: 32498113 DOI: 10.1002/phar.2432] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2020] [Revised: 05/03/2020] [Accepted: 05/03/2020] [Indexed: 11/09/2022]
Abstract
OBJECTIVES To evaluate the pharmacokinetic properties and safety of empagliflozin, and the bioequivalence of test formulation empagliflozin tablet compared with the brand-name drug Jardiance (reference formulation) after single oral administration under fasting and fed conditions in healthy Chinese subjects. METHODS An open-label randomized single-dose two-sequence, two-treatment, two-period crossover study was conducted in healthy Chinese subjects, with 30 subjects under fasting condition and another 30 subjects under fed condition. Under each condition, subjects received a single oral administration of either the test or reference empagliflozin formulation, and then they received a single oral dose of the other formulation after a 7-day washout period. RESULTS A total of 29 subjects under each condition completed the study. The maximum plasma drug concentration, the area under the plasma concentration-time curve (AUC) from 0 to t (AUC0-t ), and the AUC from 0 to infinity (AUC0-∞ ) of test formulation and reference formulation was 186.90 ± 47.21 and 190.60 ± 40.94 ng/ml, 1303.04 ± 234.28 and 1267.78 ± 217.07 ng·hour/ml, and 1328.08 ± 243.84 and 1293.22 ± 224.82 ng·hour/ml under fasting condition, and 151.55 ± 23.86 and 154.08 ± 30.40 ng/ml, 1215.65 ± 197.62 and 1199.26 ± 186.23 ng·hour/ml, and 1241.76 ± 202.47 and 1225.54 ± 192.10 ng·hour/ml under fed condition, respectively. CONCLUSIONS The two formulations of empagliflozin were bioequivalent, and both were generally well tolerated under fasting and fed conditions.
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Effects of tension fatigue on the structure and properties of carbon black filled-SBR and SBR/TPI blends. JOURNAL OF POLYMER ENGINEERING 2019. [DOI: 10.1515/polyeng-2019-0289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The aim of this study was to explore the impact of tension fatigue on the structure and properties of filled SBR and SBR/TPI blends. The effect of tension fatigue on the dynamic properties of carbon black-filled styrene-butadiene rubber (SBR) and SBR/trans-1,4-polyisoprene (SBR/TPI) blend vulcanizates were investigated by dynamic mechanical analysis (DMA). The Mooney-Rivlin analysis of tensile stress-strain data is used for the determination of a rubber network crosslink density. The fatigue fracture surface of SBR/TPI vulcanizates was observed with a scanning electron microscopy (SEM). The crystallinity of TPI in carbon black-filled SBR/TPI (80/20) was characterized by X-ray diffraction (XRD). The results showed that the incorporation of TPI into SBR vulcanizates influences the fatigue properties of the blend vulcanizates. The blend vulcanizates showed optimum fatigue properties with 20 phr TPI. With increasing fatigue cycles, the tensile properties and crosslink density of SBR vulcanizates were decreased substantially. Compared with that of SBR vulcanizates, the tensile properties and crosslink density of SBR/TPI (80/20) blend vulcanizates changed little with the increase in fatigue cycles, and tan δ and E′ decreased gradually with the fatigue cycles. There was a sharp decrease in the E′ and tan δ curve in the temperature range of 40 ~ 60°C. The XRD diffraction peak corresponding to 3.9 Å broadened when the fatigue cycles were increased to 1 million times, and a new peak with inter-planar spacing at 7.6 and 4.7 Å appeared.
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Comparison of crystallization behavior of Trans-1,4-polyisoprene under different crystallization temperature, pressure and tension. JOURNAL OF POLYMER RESEARCH 2019. [DOI: 10.1007/s10965-019-1830-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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22
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Clinical responses and pharmacokinetics of fully human BCMA targeting CAR T-cell therapy in relapsed/refractory multiple myeloma. J Clin Oncol 2019. [DOI: 10.1200/jco.2019.37.15_suppl.8013] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
8013 Background: Previous studies indicate patients with relapsed/refractory multiple myeloma (RRMM) who receive high-dose BCMA-targeting CAR-T cells may achieve better remission but have worse adverse events. Moreover, once the disease progresses again, the re-infusion of CAR-T cells is not effective. To solve this dilemma, we have developed a novel BCMA-targeting CAR-T (CT103A) with a lentiviral vector containing a CAR structure with a fully human scFv, CD8a hinger and transmembrane, 4-1BB co-stimulatory and CD3z activation domains. Methods: ChiCTR1800018137 is a single-center and single-arm trial of CT103A in patients with RRMM. The primary objectives are to characterize the safety and tolerability in patients with R/R MM. The secondary objectives include evaluation of anti-myeloma activity, cytokines, CAR-T cell persistence, and pharmacokinetics. Between September 21, 2018, and January 21, 2019, nine patients (including 3 patients having relapsed after being given a murine BCMA CAR-T) received CT103A in 3+3 dose-escalation trial (three doses at 1, 3, 6 ×106/kg) after a conditioning chemotherapy regimen of cyclophosphamide and fludarabine. All Patients had received a median of 4 prior lines (range 3 - 5) of MM therapy. Results: At the time of the February 4, 2019 data analysis, the overall response rate was 100% (Table), and all patients had a rapid response within 14 days, with 67% (2/3) reaching CR/sCR at the lowest dose. The pharmacokinetics of CT103A were assessed by a digital polymerase chain reaction. Robust expansions were seen even at the lowest dosage level. In addition, Cmax and AUC0-28 reached levels comparable to reported CD19 CAR-T. In the first two dose groups, the grade of cytokine release syndrome (CRS) was 0 - 2. In the 6 ×106 /kg dose group, DLT had been observed in one patient. Conclusions: Data from this early-stage clinical study showed the unparalleled safety and efficacy of CT103A. Major AEs were transient, manageable, and reversible. three patients who relapsed the murine BCMA CAR-T were treated with CT103A, two patients achieved CR, and one patient achieved VGPR. 100% ORR and a rapid response within 2 weeks, suggests CT103A could be developed as a competitive therapeutic to treat patients with RRMM. Treatment Response (Case 1,5 and 7 are patients who relapsed the murine BCMA CAR-T). Clinical trial information: ChiCTR1800018137. [Table: see text]
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Interactions Between an Ionic Liquid and Silica, Silica and Silica, and Rubber and Silica and Their Effects on the Properties of Styrene-Butadiene Rubber Composites. J MACROMOL SCI B 2019. [DOI: 10.1080/00222348.2018.1546266] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Pharmacokinetics and bioequivalence of two strontium ranelate formulations after single oral administration in healthy Chinese subjects. Xenobiotica 2018; 49:457-462. [PMID: 29676197 DOI: 10.1080/00498254.2018.1465210] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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25
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Multiple shape memory effects oftrans-1,4-polyisoprene and low-density polyethylene blends. POLYM INT 2017. [DOI: 10.1002/pi.5387] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Facile fabrication of a superhydrophobic surface from natural Eucommia
rubber. POLYM ADVAN TECHNOL 2017. [DOI: 10.1002/pat.4005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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GABA-B Agonist Baclofen Normalizes Auditory-Evoked Neural Oscillations and Behavioral Deficits in the Fmr1 Knockout Mouse Model of Fragile X Syndrome. eNeuro 2017; 4:ENEURO.0380-16.2017. [PMID: 28451631 PMCID: PMC5394929 DOI: 10.1523/eneuro.0380-16.2017] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 02/09/2017] [Accepted: 02/13/2017] [Indexed: 12/15/2022] Open
Abstract
Fragile X syndrome is a genetic condition resulting from FMR1 gene mutation that leads to intellectual disability, autism-like symptoms, and sensory hypersensitivity. Arbaclofen, a GABA-B agonist, has shown efficacy in some individuals with FXS but has become unavailable after unsuccessful clinical trials, prompting interest in publicly available, racemic baclofen. The present study investigated whether racemic baclofen can remediate abnormalities of neural circuit function, sensory processing, and behavior in Fmr1 knockout mice, a rodent model of fragile X syndrome. Fmr1 knockout mice showed increased baseline and auditory-evoked high-frequency gamma (30-80 Hz) power relative to C57BL/6 controls, as measured by electroencephalography. These deficits were accompanied by decreased T maze spontaneous alternation, decreased social interactions, and increased open field center time, suggestive of diminished working memory, sociability, and anxiety-like behavior, respectively. Abnormal auditory-evoked gamma oscillations, working memory, and anxiety-related behavior were normalized by treatment with baclofen, but impaired sociability was not. Improvements in working memory were evident predominantly in mice whose auditory-evoked gamma oscillations were dampened by baclofen. These findings suggest that racemic baclofen may be useful for targeting sensory and cognitive disturbances in fragile X syndrome.
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Preparation of epoxidizedEucommia ulmoidesgum and its application in styrene-butadiene rubber (SBR)/silica composites. POLYM ADVAN TECHNOL 2016. [DOI: 10.1002/pat.3863] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Anticoccidial evaluation of a traditional chinese medicine—Brucea javanica—in broilers. Poult Sci 2016; 95:811-8. [DOI: 10.3382/ps/pev441] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 11/08/2015] [Indexed: 01/04/2023] Open
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An LC-MS/MS method for simultaneous determination of cefprozil diastereomers in human plasma and its application for the bioequivalence study of two cefprozil tablets in healthy Chinese volunteers. Biomed Chromatogr 2016; 30:288-93. [PMID: 26129932 DOI: 10.1002/bmc.3547] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Revised: 06/05/2015] [Accepted: 06/12/2015] [Indexed: 11/06/2022]
Abstract
A rapid and sensitive liquid chromatography-tandem mass spectrometric method was developed for the first time and validated for the determination of cefprozil diastereomers in human plasma. The plasma samples were prepared by protein precipitation using acetonitrile. Detection was performed using an electronic spray ion source in the negative ion mode, operating in the multiple reaction monitoring of the transitions m/z 388.0 to m/z 205.0 for cefprozil diastereomers and m/z 346.1 to m/z 268.1 for cephalexin (the internal standard). The calibration curves of cis-cefprozil and trans-cefprozil were linear in the ranges 0.125-16.0 µg/mL and 0.0403-1.72 µg/mL, respectively. The lower limits of quantification of cis- and trans-cefprozil were 0.125 and 0.0403 µg/mL in human plasma, respectively. The intra- and inter-day precisions of cis- and trans-cefprozil were all <9.7%, and the accuracy ranged from 99.2 to 104.7% and from 100.6 to 102.2%, respectively. The validated method was successfully applied to a bioequivalence study of two cefprozil formulations in 24 healthy Chinese volunteers. The two cefprozil tablets were bioequivalent by measurement of cis-, trans- and total cefprozil. We suggest that the bioequivalence of cefprozil formulations can be evaluated only using cis-cefprozil as the analyte in future studies.
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Abstract
1.The aim of the study was to evaluate the pharmacokinetics of peramivir after single intravenous (i.v.) doses in healthy Chinese subjects. 2.In a cross-over study, 12 subjects were given 300 and 600 mg peramivir by i.v. infusion. Blood and urine samples were collected at 17 designated time points and 7 designated intervals up to 36 h post-dose. Plasma and urine concentrations of peramivir were quantified by LC-MS/MS. 3.After single i.v. doses of 300 and 600 mg peramivir, Cmax and AUC0-t of peramivir were 21.4 ± 3.7, 41.1 ± 5.3 mgċL(-1) and 55.90 ± 10.62, 112.1 ± 13.2 mgċh L(-1), respectively. Cmax and AUC increased in proportion to the dose. Within 12 h, accumulative urinary recoveries of peramivir after single i.v. doses of 300 and 600 mg peramivir were 84.31 ± 11.75% and 88.10 ± 7.39%, respectively. 4.In healthy Chinese subjects, peramivir displayed linear pharmacokinetics in the range of 300-600 mg, and was primarily excreted via urine as unchanged drug.
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Regulation of lovastatin on a key inflammation-related microRNA in myocardial cells. Chin Med J (Engl) 2014; 127:2977-2981. [PMID: 25131238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023] Open
Abstract
BACKGROUND Advances in the understanding of cardiovascular pathogenesis have highlighted that inflammation plays a central role in atherosclerotic coronary heart disease. Therefore, exploring pharmacologically based anti-inflammatory treatments to be used in cardiovascular therapeutics is worthwhile to promote the discovery of novel ways of treating cardiovascular disorders. METHODS The myocardial cell line H9c2(2-1) was exposed to lipopolysaccharide (LPS) in culture and resulted in a cellular pro-inflammation status. miR-21 microRNA levels were detected using quantitative real-time polymerase chain reaction (Q-RT-PCR). The influence of lovastatin on miR-21 under normal and pro-inflammatory conditions was tested after being added to the cell culture mixture for 24 hours. Conditional gene function of two predicted cardiovascular system relevant downstream targets of miR-21, protein phosphatase 1 regulatory subunit 3A (PPP1R3A) and signal transducer and activator of transcription 3 (STAT3), were analyzed with immunoblotting. RESULTS Forty-eight hours of LPS treatment significantly increased the miR-21 to 170.71%± 34.32% of control levels (P = 0.002). Co-treatment with lovastatin for 24 hours before harvesting attenuated the up-regulation of miR-21 (P = 0.013). Twenty-four hours of lovastatin exposure up-regulated PPP1R3A to 143.85%± 21.89% of control levels in cardiomyocytes (P = 0.023). Lovastatin up-regulated the phosphorylation level of STAT3 compared to the background LPS pretreatment (P = 0.0077), this effect was significantly (P = 0.018) blunted when miR-21 was functionally inhibited. CONCLUSIONS miR-21 plays a major role in the regulation of the cellular anti-inflammation effects of lovastatin.
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Association between copy number variations of HLA-DQA1 and ankylosing spondylitis in the Chinese Han population. Genes Immun 2013; 14:500-3. [PMID: 24048351 PMCID: PMC3855587 DOI: 10.1038/gene.2013.46] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 08/02/2013] [Accepted: 08/05/2013] [Indexed: 11/20/2022]
Abstract
Ankylosing spondylitis (AS) is a chronic inflammatory disease with complex genetic traits. Multiple sequence variations have been associated with AS, but explained only a proportion of heritability. The studies herein aimed to explore potential associations between genomic copy number variation (CNV) and AS of Han Chinese. Five AS patients were examined with the high-density comparative genomic hybridization (CGH) microarrays in the first screen test for AS associated CNVs. A total of 533 AS patients and 792 unrelated controls were examined in confirmation studies with the AccuCopy assays. A significant association was observed between the CNV of the HLA-DQA1 and AS. Comparing with controls, AS patients showed an aberrant copy number (CN), and significantly increased number of patients had more than 2 copies of the HLA-DQA1. Therefore, CNV of the HLA-DQA1 may play an important role in susceptibility to AS in Han Chinese population.
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LC-MS/MS method for the determination of agomelatine in human plasma and its application to a pharmacokinetic study. Biomed Chromatogr 2013; 28:218-22. [PMID: 23918681 DOI: 10.1002/bmc.3008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 07/03/2013] [Accepted: 07/05/2013] [Indexed: 11/11/2022]
Abstract
A sensitive and selective LC-MS/MS method for the determination of agomelatine in human plasma was developed and validated. After simple liquid-liquid extraction, the analytes were separated on a Zorbax SB-C18 column (150 × 2.1 mm i.d., 5 µm) with an isocratic mobile phase consisting of 5 mm ammonium acetate solution (containing 0.1% formic acid) and methanol (30:70, v/v) at a flow-rate of 0.3 mL/min. The MS acquisition was performed in multiple reaction monitoring mode with a positive electrospray ionization source. The mass transitions monitored were m/z 244.1 → 185.3 and m/z 285.2 → 193.2 for agomelatine and internal standard, respectively. The methods were validated for selectivity, carry-over, matrix effects, calibration curves, accuracy and precision, extraction recoveries, dilution integrity and stability. The validated method was successfully applied to a pharmacokinetic study of agomelatine in Chinese volunteers following a single oral dose of 25 mg agomelatine tablet.
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Effects of Chlorinated Trans-1,4-polyisoprene on Cure, Morphology, and Mechanical Properties of Neoprene Blends and Their Vulcanizates. J MACROMOL SCI B 2010. [DOI: 10.1080/00222341003595675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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The effect of pyrolytic carbon black prepared from junked tires on the properties of ethylene-propylene-diene copolymers (EPDM). EXPRESS POLYM LETT 2009. [DOI: 10.3144/expresspolymlett.2009.37] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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The Effect of Oil‐Extension on the Properties of TPI and TPI/SBR Vulcanizates. J MACROMOL SCI B 2008. [DOI: 10.1080/00222340802119232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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The Characterization of Pyrolytic Carbon Black Prepared from Used Tires and Its Application in Styrene–Butadiene Rubber (SBR). J MACROMOL SCI B 2008. [DOI: 10.1080/00222340701748768] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Abstract
A liquid and a powder made from a herbal complex consisting of Uncariae Ramulus cum Uncis, Agrimoniae Herba, Sanguisorbae Radix, Eclipta Prostrate Herba, Pulsatillae Radix, Sophorae Flavescentis Radix, Rehmanniae Radix and Glycyrrhizae Radix were studied for their anticoccidial activities in chickens. Chickens were administered with herbal liquid, powder, diclazuril or without medication during the study and challenged with oocysts of Eimeria tenella. Results indicated that the birds medicated showed less bloody faeces than those without medication. The intestinal lesion was mild in the chicks medicated with herbal liquid without significantly different lesion score when compared with uninfected chicks. The birds with medication had significantly higher body weight gains than birds without medication. Therefore, the herbal complex used in this study was effective against E. tenella infection in chickens.
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Polymerization conversion and structure of magnesium methacrylate in ethylene-vinyl acetate rubber vulcanizates. J Appl Polym Sci 2004. [DOI: 10.1002/app.20583] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Properties of EVM vulcanizates reinforced byin situ prepared sodium methacrylate. J Appl Polym Sci 2003. [DOI: 10.1002/app.12476] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Determination of (187)Os in molybdenite by ICP-MS with neutron-induced (186)Os and (188)Os spikes. Talanta 2001; 55:815-20. [PMID: 18968429 DOI: 10.1016/s0039-9140(01)00506-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2000] [Revised: 07/02/2001] [Accepted: 07/03/2001] [Indexed: 10/18/2022]
Abstract
The article describes a method for the determination of (187)Os in molybdenite by isotope dilution inductively coupled plasma-mass spectrometry (ID-ICP-MS) with neutron-induced (186)Os and (188)Os spike. The spike used in the present work was prepared in line with the principle by which artificial nuclides are produced in a nuclear reaction. The concentration and isotopic composition of osmium in the prepared spike were evaluated accurately with the isotope dilution method, using negative thermal ion mass spectrometry (N-TIMS). The advantage of this method is that using (186)Os and (188)Os double spikes can effectively compensate for the mass discrimination effects of ICP-MS. Thus, the common correction practice for mass bias in the isotope dilution method with a single spike is unnecessary. In addition, the method enables one to reduce the determined error arising from instrumental instability. The precision for the (187)Os/((186)Os+(188)Os) ratio was approximately 2% (2sigma, RSD), but in the case of (187)Os/(186)Os, (187)Os/(188)Os and (186)Os/(188)Os, precision ranged from 2.0 to 8% (2sigma, RSD). The results for (187)Os concentration in a molybdenite sample determined with this method showed good agreement with reference values.
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Disposition of glutathione conjugates in rats by a novel glutamic acid pathway: characterization of unique peptide conjugates by liquid chromatography/mass spectrometry and liquid chromatography/NMR. J Pharmacol Exp Ther 2000; 294:735-45. [PMID: 10900255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
With the advent of liquid chromatography/mass spectrometry and liquid chromatography/NMR, it has become easier to characterize metabolites that were once difficult to isolate and identify. These techniques have enabled us to uncover the existence of an alternate pathway for the disposition of glutathione adducts of several structurally diverse compounds. Studies were carried out using acetaminophen as a model compound to investigate the role of the glutamic acid pathway in disposition of the glutathione adducts. Although the mercapturic acid pathway was the major route of degradation of the glutathione adducts, it was found that the conjugation of the glutathione, cysteinylglycine, and cysteine adducts of acetaminophen with the gamma-carboxylic acid of the glutamic acid was both interesting and novel. The coupling of the glutathione adduct and the products from the mercapturic acid pathway with the glutamic acid led to unusual peptide conjugates. The natures of these adducts were confirmed unequivocally by comparisons with synthetic standards. This pathway (addition of glutamic acids) led to larger peptides, in contrast to the mercapturic acid pathway, in which the glutathione adducts are broken down to smaller molecules. The enzyme responsible for the addition of glutamic acid to the different elements of the mercapturic acid pathway is currently unknown. It is postulated that the gamma-carboxylic acid is activated (perhaps by ATP) before enzymatic addition to the alpha-amino group of cysteine or glutamate takes place. The discovery of these peptide conjugates of acetaminophen represents a novel disposition of glutathione adducts of compounds. The formation of such conjugates may represent yet another pathway by which drugs could produce covalent binding via their reactive intermediates.
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Characterization of novel glutathione adducts of a non-nucleoside reverse transcriptase inhibitor, (S)-6-chloro-4-(cyclopropylethynyl)-4-(trifluoromethyl)-3, 4-dihydro-2(1H)-quinazolinone (DPC 961), in rats. Possible formation of an oxirene metabolic intermediate from a disubstituted alkyne. Chem Res Toxicol 2000; 13:775-84. [PMID: 10956066 DOI: 10.1021/tx000029g] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The postulated formation of oxirene-derived metabolites from rats treated with a disubstituted alkyne, (S)-6-chloro-4-(cyclopropylethynyl)-4-(trifluoromethyl)-3, 4-dihydro-2(1H)-quinazolinone (DPC 961), is described. The reactivity of this postulated oxirene intermediate led to the formation of novel glutathione adducts whose structures were confirmed by LC/MS and by two-dimensional NMR experiments. These metabolites were either excreted in rat bile or degraded to mercapturic acid conjugates and eliminated in urine. To demonstrate the oxidation of the triple bond, an analogue of DPC 961 was synthesized, whereby the two carbons of the alkyne moiety were replaced with (13)C stable isotope labels. Rats were orally administered [(13)C]DPC 961 and glutathione adducts isolated from bile. The presence of an oxygen atom on one of the (13)C labels of the alkyne was demonstrated unequivocally by NMR experiments. Administration of (14)C-labeled DPC 961 showed that biliary elimination was the major route of excretion with the 8-OH glucuronide conjugate (M1) accounting for greater than 90% of the eliminated radioactivity. On the basis of radiochemical profiling, the glutathione-derived metabolites were minor in comparison to the glucuronide conjugate. Studies with cDNA-expressed rat enzymes, polyclonal antibodies, and chemical inhibitors pointed to the involvement of P450 3A1 and P450 1A2 in the formation of the postulated oxirene intermediate. The proposed mechanism shown in Scheme 1 begins with P450-catalyzed formation of an oxirene, rearrangement to a reactive cyclobutenyl ketone, and a 1,4-Michael addition with endogenous glutathione to produce two isomeric adducts, GS-1 and GS-2. The glutathione adducts were subsequently catabolized via the mercapturic acid pathway to cysteinylglycine, cysteine, and N-acetylcysteine adducts. The transient existence of the alpha,beta-unsaturated cyclobutenyl ketone was demonstrated by incubating the glutathione adduct in the presence of N-acetylcysteine and monitoring the formation of N-acetylcysteine adducts by LC/MS. Epimerization of GS-1 to GS-2 was also observed when N-acetylcysteine was omitted from the incubation.
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[The role of bFGF in renal tubular injury and the interstitial lesion]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2000; 29:208-11. [PMID: 11866915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE The role of bFGF in renal tubular injury, regeneration and interstitial lesion of rats was studied. METHODS The renal tubular injury model of rat was induced by intraperitoneal injection of gentamicin. The expression of bFGF and FGFR1 was examined by Northern blot, in situ hybridization and immunohistochemistry. (3)H-TdR incorporation was used to detect the role of bFGF in promoting the proliferation of renal tubular epithelial cells and renal fibroblasts. RESULTS The expression of bFGF mRNA and protein synthesis of bFGF and FGFR1 increased during the process of injury and regeneration of tubular epithelial cells. In contrast, normal tubular epithelium failed to express bFGF, except renal interstitial fibroblasts and monocytes/macrophages. bFGF promoted proliferation of renal tubular epithelium as well as renal interstitial fibroblasts. CONCLUSION bFGF is secreted by tubular epithelial cells damaged by nephrotoxicity of gentamicin, and FGFR1 expressed in damaged renal tubules and interstitial fibroblasts. bFGF not only can promote tubular epithelia to proliferate, but can also stimulate interstitial fibroblasts to proliferate. Correlation exists between bFGF, renal tubular injury and interstitial lesions.
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Abstract
BACKGROUND Myosin II, a conventional myosin, is dispensable for mitotic division in Dictyostelium if the cells are attached to a substrate, but is required when the cells are growing in suspension. Only a small fraction of myosin II-null cells fail to divide when attached to a substrate. Cortexillins are actin-bundling proteins that translocate to the midzone of mitotic cells and are important for the formation of a cleavage furrow, even in attached cells. Here, we investigated how myosin II and cortexillin I cooperate to determine the position of a cleavage furrow. RESULTS Using a green fluorescent protein (GFP)-cortexillin I fusion protein as a marker for priming of a cleavage furrow, we found that positioning of a cleavage furrow occurred in two steps. In the first step, which was independent of myosin II and substrate, cortexillin I delineated a zone around the equatorial region of the cell. Myosin II then focused the cleavage furrow to the middle of this cortexillin I zone. If asymmetric cleavage in the absence of myosin II partitioned a cell into a binucleate and an anucleate portion, cell-surface ruffles were induced along the cleavage furrow, which led to movement of the anucleate portion along the connecting strand towards the binucleate one. CONCLUSIONS In myosin II-null cells, cleavage furrow positioning occurs in two steps: priming of the furrow region and actual cleavage, which may proceed in the middle or at one border of the cortexillin ring. A control mechanism acting at late cytokinesis prevents cell division into an anucleate and a binucleate portion, causing a displaced furrow to regress if it becomes aberrantly located on top of polar microtubule asters.
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[The enantiomeric separation of aromatic alcohol amino drugs by thin-layer chromatography]. Se Pu 1999; 17:215-6. [PMID: 12549175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023] Open
Abstract
Two chiral aromatic alcohol amino drugs, Labarol and Bataroc, were resolved by thinlayer chromatography (TLC) on the silica gel GF254 plates (2.5 cm x 10 cm), by using the ammonium-D-10-camphorsulfonate (CSA) as chiral ion-pair interaction agent which was added to the mobile phase in the ammonium form. All developments were carried out at lower temperature (2-4 degrees C, in a refrigerator) in small glass jars of 250 mL volume. These two drugs were not resolved at room temperature (15-30 degrees C). Analytical reagent grade methanol and dichloromethane can be directly used as mobile phase without further drying. The chiral separation occured over a range from 40% to 70% (optimum 67%) dichloromethane in the mobile phase volume ratio and 55% to 80% (optimum 60%) dichloromethane in the mobile phase volume ratio. These separation conditions were easily obtained. This method is relatively inexpensive and attractive.
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[The preparation of chiral column of cellulose triacetate coated on small pore silica gel and the separation of enantiomers]. Se Pu 1998; 16:47-9. [PMID: 11324478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
The cellulose triacetate (CTA) prepared by heterogeneous acetylation and coated on small pore 3-aminopropyl silica gel (10 nm) was used as chiral stationary phase for HPLC (OA column). The racemes of three drugs, two fulvenes and one dazine, were separated on this column. Among these racemes, timolol maleas was separated using 1.0 mol/L NaClO4:95% ethanol = 10:90 as mobile phase. Without NaClO4 in mobile phase, the resolution of timolol maleas can not occur. Ethanols of 95%-98% were used as mobile phase for other racemes. The influence of the content of water in mobile phase on the chiral separation of praziquentelum, the retention time and separation factor (alpha) were reduced with the increase of water content in mobile phase. When the content of water in the mobile phase was 13%, praziquentelum could not be separated. It was found that in the case of samples No. 1 and No. 2, when the substituents R1 and R2 or R'1 and R'2 of fulvenes are 4-methoxybenzoyl and 4-methoxyphenyl, the chiral separations of fulvenes can be obtained. For sample No. 4 when R1 and R2 of fulvenes are 2-methylbenzoyl and 2-methylphenyl or in the case of No. 5, when R1 and R2 are 5-bromo-2-furoyl and 5-bromo-2-furan, the chiral separations of fulvenes can not be achieved. For sample No. 6 and No. 7, when R'1 are 4-chlorobenzoyl and benzoyl or R'2 are 4-chlorophenyl and phenyl, the chiral separation also can not be achieved. The column performance and separation factor were not obviously reduced after used for four months.
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