GC-MS platform has been proved to be an important analytical technique for plasma metabolomics, but lack of efficient sample preparation strategies prior to sample injection has limited its wide application. In the present work, twenty two extraction protocols including protein precipitation (PPT), liquid-liquid extraction (LLE), solid-phase extraction (SPE) and ultrafiltration were simultaneously evaluated using non-spiked and metabolite standards spiked human plasma. Sample-to-extraction solvent ratio and metabolites derivatization conditions were also investigated and optimised. The results demonstrated that stepwise LLE protocol (MeOH-HO/CHCl/CHCl-MeOH) was the most efficient extraction strategy for the combination of untargeted and targeted metabolomics. Sample-to-extraction solvent ratio of 1:3 (v:v) was found to perform better than higher solvent ratios. Also, the maximum derivatization performance was obtained when using 30 μL N-methyl-N-tri-methylsilyltrifluoroacetamide (MSTFA) and 1% trimethyl-chlorosilane (TMCS) incubated at 60 °C for 120 min. In the end, the optimised sample preparation method was applied successfully to plasma untargeted metabolomics of rheumatoid arthritis (RA) and four metabolites (gamma-butyrolactone, MG (0:0/18:0/0:0), tocopherol and oxalic acid) were found to be potential biomarkers for the diagnosis of RA.
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http://dx.doi.org/10.1016/j.aca.2020.06.029 | DOI Listing |
Diagn Pathol
January 2025
Cell Culture Laboratory, School of Dentistry, Federal University of Para, Rua Augusto Correa, 01 Guama, Belem, PA, 66075110, Brazil.
Background: Considering the significant participation of the microenvironment in the local aggressiveness of odontogenic keratocysts, this study aims to evaluate the expression of ADAMTS-1 and its substrates, versican, aggrecan and brevican in this locally invasive odontogenic cyst.
Methods: Immunohistochemistry and polymerase chain reaction (PCR) were conducted on 30 cases of odontogenic keratocysts (OKCs) and 20 dental follicles (DFs).
Results: The immunohistochemical expression of these proteins was predominantly cytoplasmic and granular across all samples.
BMC Health Serv Res
January 2025
Department of Pharmaceutics and Social Pharmacy, School of Pharmacy, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia.
Background: Extemporaneous compounding for dermatological use is an important therapeutic alternative for patients whose clinical needs are not met by approved drug products circulated in the market. Evaluating patients' perceptions and levels of satisfaction towards such services is an important factor for the adherence of patients and maintaining the quality of healthcare services. The current study aimed to assess patients' perception and level of satisfaction with the compounding service and extemporaneous preparations rendered at ALERT hospital.
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January 2025
Department of Chemistry, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh, 11623, Saudi Arabia.
In this study, we report the synthesis of iron oxide nanoparticles (FeONPs) using micro-emulsion-hydrothermal method. By adjusting the synthesis temperature, we successfully produced FeO nanorods and nanospheres. In addition, the 2-octanol, and the surfactant cetyltrimethylammonium bromide served as a solvent in the synthesis process.
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January 2025
Department of Chemistry, Faculty of Science, Al-Azhar University, Nasr City, 11884, Cairo, Egypt.
A Schiff base of Chitosan was prepared by condensing of the Chitosan (CS) with six aromatic aldehydes and confirmed by FT-IR, NMR, XRD, TGA, and DSC. XRD results showed the disappeared of peaks at 2θ = 10° for CS and appeared one peaks at around 2θ of 23° for Schiff bases, while TGA was demonstrated that the thermal stability of CS has improved after the modification with the corresponding aldehyde. Also, DSC shows endothermal peak of CS at 100 °C due to the loss of water and second thermal event related to the decomposition of amine units with an exothermic peak at 295 °C, while Schiff bases shows endothermal peak around 70-95 °C which is related to the loss of water for all samples and the second exothermic peak around 260-280 °C is related to the decomposition of the amine group in the polymer units.
View Article and Find Full Text PDFPurpose: Holistic review for admissions is designed to mitigate the common systemic barriers applicants may face in their medical school application journey and the common mistakes committed by admissions committees, but limited literature outlines how this can be modeled. This study examined a blinded holistic admissions approach that emphasized mission and value alignment and the resulting characteristics of applicants by admission status.
Method: Application data from 2,027 applicants to The University of Texas at Tyler School of Medicine with complete secondary applications for the 2022 to 2023 cycle were analyzed.
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