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101.
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Karen Y. Kwok Timmy L. S. Choi Wai Him Kwok Ming Yip Lau Elvis M. K. Leung Gary N. W. Leung Jenny K. Y. Wong Terence S. M. Wan Farrington F. Adrian Anil Prabhu Emmie N. M. Ho 《Drug testing and analysis》2020,12(9):1274-1286
The use of bioactive peptides as a doping agent in both human and animal sports has become increasingly popular in recent years. As such, methods to control the misuse of bioactive peptides in equine sports have received attention. This paper describes a sensitive accurate mass method for the detection of 40 bioactive peptides and two non‐peptide growth hormone secretagogues (< 2 kDa) at low pg/mL levels in horse urine using ultra‐high performance liquid chromatography‐high resolution mass spectrometry (UHPLC/HRMS). A simple mixed‐mode cation exchange solid‐phase extraction (SPE) cartridge was employed for the extraction of 42 targets and/or their in vitro metabolites from horse urine. The final extract was analyzed using UHPLC/HRMS in positive electrospray ionization (ESI) mode under both full scan and data independent acquisition (DIA, for MS2). The estimated limits of detection (LoD) for most of the targets could reach down to 10 pg/mL in horse urine. This method was validated for qualitative detection purposes. The validation data, including method specificity, method sensitivity, extraction recovery, method precision, and matrix effect were reported. A thorough in vitro study was also performed on four gonadotrophin‐releasing factors (GnRHs), namely leuprorelin, buserelin, goserelin, and nafarelin, using the S9 fraction isolated from horse liver. The identified in vitro metabolites have been incorporated into the method for controlling the misuse of GnRHs. The applicability of this method was demonstrated by the identification of leuprorelin and one of its metabolites, Leu M4, in urine obtained after intramuscular administration of leuprorelin to a thoroughbred gelding (castrated horse). 相似文献
104.
Rahul S. Bhansali Malini Rammohan Paul Lee Anouchka P. Laurent Qiang Wen Praveen Suraneni Bon Ham Yip Yi-Chien Tsai Silvia Jenni Beat Bornhauser Aurlie Siret Corinne Fruit Alexandra Pacheco-Benichou Ethan Harris Thierry Besson Benjamin J. Thompson Young Ah Goo Nobuko Hijiya Maria Vilenchik Shai Izraeli Jean-Pierre Bourquin Sbastien Malinge John D. Crispino 《The Journal of clinical investigation》2021,131(1)
105.
Chia-Cheng Tseng Chin-Chou Wang Huang-Chih Chang Tzu-Hsien Tsai Li-Teh Chang Kuo-Tung Huang Steve Leu Chia-Hung Yen Shih-Feng Liu Chih-Hung Chen Cheng-Ta Yang Hon-Kan Yip Meng-Chih Lin 《Disease markers》2013,35(5):301-310
Background. Endothelial-derived microparticles (EDMPs) and platelet-derived microparticles (PDMPs) have been reported to be increasing in various diseases including malignant diseases. Here, we investigated whether these MPs may be useful biomarkers for predicting lung cancer (LC) disease status, cell type, or metastasis. Methods and Results. One hundred and thirty LC patients were prospectively enrolled into the study between April 2011 and February 2012. Flow cytometric analysis demonstrated that the circulating levels of platelet-derived activated MPs (PDAc-MPs), platelet-derived apoptotic MPs (PDAp-MPs), endothelial-derived activated MPs (EDAc-MPs), and endothelial-derived apoptotic MPs (EDAp-MPs) were significantly higher in LC patients than in 30 age- and gender-matched normal control subjects (all P < 0.05). Additionally, circulating level of PDAc-MPs was significantly lower (P = 0.031), whereas the circulating levels of the other three biomarkers did not differ (all P > 0.1) in early stage versus late stage LC patients. Furthermore, the circulating levels of the four types of MPs did not differ among patients with different disease statuses (i.e., disease controlled, disease progression, and disease without treatment, i.e., fresh case) (all P > 0.2) or between patients with or without LC metastasis (all P > 0.5). Moreover, only the circulating level of EDAp-MPs was significantly associated with the different cell types (i.e., squamous cell carcinoma, adenocarcinoma, and small cell carcinoma) of LC (P = 0.045). Conclusion. Circulating MP levels are significantly increased in LC patients as compared with normal subjects. Among the MPs, only an increased level of EDAp-MPs was significantly associated with different LC cell types. 相似文献
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107.
Ni Sann Khin Sze Huey Tan Michael LC Wang Tian Rui Siow Faye LWT Lim Fu Qiang Wang Matthew CH Ng Justina YC Lam Connie Yip 《The British journal of radiology》2021,94(1122)
Objective:Chemoradiation (CRT) may induce a change in systemic inflammatory state which could affect clinical outcomes in oesophageal cancer. We aimed to evaluate the changes and prognostic significance of systemic inflammatory markers following definitive CRT in oesophageal squamous cell carcinoma.Methods:A total of 53 patients treated with concurrent CRT were included in this retrospective analysis. We compared neutrophils, lymphocytes, platelets, neutrophil–lymphocyte ratio (NLR) and platelet–lymphocyte ratio (PLR) before and after CRT using Wilcoxon signed-rank test. Overall survival (OS) and progression-free survival (PFS) were calculated. Univariable and multivariable survival analysis were performed using Cox regression analysis. Clinical univariable survival prognostic factors with p < 0.1 were included in a multivariable cox regression analysis for backward stepwise model selection.Results:Both NLR (median ∆+2.8 [IQR −0.11, 8.62], p < 001) and PLR (median ∆+227 [81.3–523.5], p < 0.001) increased significantly after CRT. Higher levels of pre-CRT, post-CRT and change (∆) in NLR and PLR were associated with inferior OS and PFS. Post-CRT NLR (HR 1.04, 95% CI 1.02–1.07, p < 0.001), post-CRT platelets (HR 1.03, 95% CI 1.01–1.05, p = 0.005), cT-stage (HR 3.83, 95% CI 1.39–10.60, p = 0.01) and RT dose (HR 0.41, 95% CI 0.21–0.81, p = 0.01) were independent prognostic factors for OS in multivariable analysis. Change in NLR (HR 1.04, 95% CI 1.01–1.06, p = 0.001), post-CRT platelets (HR 1.03, 95% CI 1.01–1.05, p = 0.002), cT-stage (HR 3.98, 95% CI 1.55–10.25, p = 0.004) and RT dose (HR 0.41, 95% CI 0.21–0.80, p = 0.009) were independent prognostic factors for PFS.Conclusion:Both NLR and PLR increased following definitive CRT. Post-CRT NLR and ∆NLR were associated with adverse survival in oesophageal SCC.Advances in knowledge:We showed that CRT increased PLR and NLR, possibly reflecting a systemic inflammatory state which were associated with poor clinical outcomes in oesophageal SCC. 相似文献
108.
109.
Packham MA; Perry DW; Kinlough-Rathbone RL; Rand ML; Guccione MA; Evans RM; Mustard JF 《Blood》1985,65(3):564-570
Rabbit platelets were aggregated by adenosine diphosphate (ADP), allowed to deaggregate and then separated into density subpopulations by centrifugation through discontinuous Stractan density gradients. Although ADP causes little or no release of the contents of the amine storage granules of rabbit platelets, ADP caused a decrease in platelet density as compared with control platelets subjected to the same procedures except for exposure to ADP. The density change persisted for at least four hours. The apparent size of platelets stimulated with ADP increased initially, but returned to control values during a one-hour period. A similar decrease in platelet density was observed with an albumin density gradient. Under conditions in which aggregation did not occur in response to ADP with ethylenediaminetetraacetic acid (EDTA) in the medium, little or no decrease in platelet density was observed. Agglutination with polylysine did not change platelet density. Thus, not only agents such as thrombin and plasmin that cause the release of the contents of the platelet granules decrease platelet density, but ADP also has this effect. Platelets would be exposed to all of these stimuli during thromboembolic processes, and their effect on platelets may account for the decrease in platelet density observed previously in experiments with rabbits with indwelling aortic catheters. Agents that increase the concentration of cyclic AMP (cAMP) in platelets (PGE1, adenosine, dibutyryl cAMP, forskolin, and papaverine) also decreased platelet density. This effect persisted when the platelets were washed and resuspended in fresh medium and was also demonstrable in plasma. Platelet size was gradually increased by prostaglandin E1 (PGE1) which maintains platelets in a disc shape and does not cause the release of granule contents, indicating that the decrease in platelet density caused by PGE1 may be attributable to platelet swelling. 相似文献