For the quantitative determination of paclitaxel in human plasma reversed-phase high-performance liquid chromatographic (HPLC) methods with solid-phase extraction (SPE) as sample pretreatment procedure are frequently used. Recovery problems arose during the quantification of paclitaxel in plasma samples of patients. The major problems were a large batch-to-batch difference in performance of the SPE columns and the effects of the pharmaceutical vehicle Cremophor EL on the performance of the SPE. Cremophor EL concentrations exceeding 1.0% (v/v) had a great impact on the absolute recovery of paclitaxel from human plasma with the SPE procedure. The recoveries decreased approximately 10 to 40% depending on the quality of the batch SPE columns. The problems are avoided by using 2'-methylpaclitaxel as the internal standard. This study points out the importance of including the effects of a pharmaceutical vehicle, like Cremophor EL, in the validation programme of a bioanalytical assay and the use of an internal standard in HPLC paclitaxel assays preceded by SPE as sample pretreatment procedure.
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http://dx.doi.org/10.1016/s0378-4347(98)00043-7 | DOI Listing |
J Pathol Clin Res
January 2025
State Key Laboratory of Holistic Integrative Management of Gastrointestinal Cancers and National Clinical Research Center for Digestive Diseases, Xijing Hospital of Digestive Diseases, Fourth Military Medical University, Xi'an, PR China.
CXC chemokine receptor 4 (CXCR4) and programmed cell death-ligand 1 (PD-L1) are two critical molecules involved in the tumor immune microenvironment. However, the impact of platinum drugs, such as cisplatin, on CXCR4 or PD-L1 expression and the underlying mechanisms in gastric cancer (GC) remain unknown. Moreover, the correlation between their expression levels in GC remains elusive.
View Article and Find Full Text PDFFront Immunol
January 2025
Department of Head and Neck Surgery, National Hospital Organization Kyushu Cancer Center, Fukuoka, Fukuoka, Japan.
Background: Nivolumab paved a new way in the treatment of patients with recurrent or metastatic (RM) head and neck squamous cell carcinoma (RM-HNSCC). However, the limited rates of long-term survivors (< 20%) demand a robust prognostic biomarker. This nationwide multi-centric prospective study aimed to identify a plasma exosome (PEX) mRNA signature, which serves as a companion diagnostic of nivolumab and provides a biological clue to develop effective therapies for a majority of non-survivors.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Department of Physics, Jinan University, Guangzhou, Guangdong 510632, P. R. China.
The solid electrolyte interphase (SEI) is considered to be the key to the performance of lithium metal batteries (LMBs). The analysis of the SEI and cathode electrolyte interphase (CEI) composition (especially F 1s spectra) by X-ray photoelectron spectroscopy (XPS) has become a consensus among researchers. However, the surface-sensitive XPS characterization is susceptible to LiF artifacts due to several factors, leading to the overexaggerated role of LiF in the analysis of the SEI and CEI.
View Article and Find Full Text PDFEur Arch Otorhinolaryngol
January 2025
Department of Otolaryngology-Head and Neck Surgery, IRCCS Regina Elena National Cancer Institute, Istituti Fisioterapici Ospitalieri (IFO), Via Elio Chianesi 53, 00144, Rome, Italy.
Objectives: we evaluated the hypothesis that level of ctHPVDNA on the first postoperative day (POD-1); and at 15 days (POD-15) could be associated with the need for adjuvant therapy and the presence of recurrence.
Materials And Methods: this is a prospective observational study on biomarkers, focusing on the longitudinal monitoring of ctHPVDNA in a cohort of HPV-OPSCC patients undergoing TORS. Blood samples were collected according to the following schema: (1) pretreatment; (2) on first postoperative day (POD 1); and (3) at 15 days (POD 15).
Eye (Lond)
January 2025
Division of Clinical Neuroscience, Department of Ophthalmology, University of Nottingham, Nottingham, UK.
Background/objectives: Anterior segment optical Coherence Tomography (AS-OCT) is used extensively in imaging the cornea in health and disease. Our objective was to analyse and monitor corneal vascularisation (CVas) through the corresponding back-shadows visible on AS-OCT.
Subjects/methods: AS-OCT scans were obtained from 26 consecutive patients (eyes) with CVas of different aetiologies.
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