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    Comparative Analysis of Salivary Gland Proteomes of Two Glossina Species that Exhibit Differential Hytrosavirus Pathologies
    (FRONTIERS MEDIA SA, 2016-01-01) Kariithi, Henry M.; Ince, Ikbal Agah; Boeren, Sjef; Murungi, Edwin K.; Meki, Irene K.; Otieno, Everlyne A.; Nyanjom, Steven R. G.; van Oers, Monique M.; Vlak, Just M.; Abd-Alla, Adly M. M.
    Glossina pallidipes salivary gland hypertrophy virus (GpSGHV
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    A comparative investigation on phenolic composition, antioxidant and antimicrobial potentials of Salvia heldreichiana Boiss. ex Bentham extracts
    (ELSEVIER, 2019-01-01) Bardakci, H.; Celep, E.; Gozet, T.; Kurt-Celep, I.; Deniz, I.; Sen-Utsukarci, B.; Akaydin, G.
    The purpose of the present work is to screen phenolic composition and evaluate the antioxidant and antimicrobial activities of the main extract and subextracts of Salvia heldreichiana, an endemic plant from Turkey. The aerial parts have been powdered and extracted with MeOH initially and then partitioned with chloroform (CHCl3), ethyl acetate (EtOAc) for the generation of subextracts along with the remaining water (R-H2O). Total phenolic, phenolic acid, flavonoid and proanthocyanidin contents present in the MeOH, CHCl3, EtOAc and R-H2O extracts were measured. Presence of 22 phenolic metabolites were confirmed by utilizing LC-MS/MS in MRM scan mode and then Rosmarinic acid (RA) contents of each extract were quantified by HPTLC-densitometry, since the biological effects of many medicinal plants, including Salvia sp. is attributed to RA content. Antioxidant capacities of the aforementioned extracts were estimated using several procedures including free radical scavenging and metal-associated activity and then disc diffusion method was employed to designate their antibacterial and antifungal activities. The results obtained from the current study has revealed a positive correlation between the phenolic composition and the antioxidant profile as well as the antimicrobial activities of the extracts. Among the tested extracts, EtOAc subextract showed the highest antioxidant and antimicrobial activities consistent with the highest phenolic and RA content. (C) 2019 SAAB. Published by Elsevier B.V. All rights reserved.
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    Evaluation of optimal urine screening and confirmation cut-off values for opiates, at a national reference laboratory
    (WALTER DE GRUYTER GMBH, 2021-01-01) Karakukcu, Cigdem; Ciraci, Mehmet Zahid; Kocer, Derya; Faydali, Mine Yuce; Serdar, Muhittin Abdulkadir
    Objectives: To obtain optimal immunoassay screening and LC-MS/MS confirmation cut-offs for opiate group tests to reduce false positive (FP) and false negative (FN) rates. Methods: A total of 126 urine samples, -50 opiate screening negative, 76 positive according to the threshold of 300 ng/mL by CEDIA method - were confirmed by a full-validated in-house LC-MS/MS method. Sensitivity, specificity, FP, and FN rates were determined at cut-off concentrations of both 300 and 2,000 ng/mL formorphine and codeine, and 10 ng/mLfor heroinmetabolite 6-mono-acetyl-morphine (6-MAM). Results: All CEDIA opiate negative urine samples were negative for morphine, codeine and 6-MAM. Although sensitivity was 100\% for each cut-off
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    Phytochemical characterization and antioxidant activities of the fruit extracts of several Crataegus taxa
    (ELSEVIER, 2019-01-01) Bardakci, H.; Celep, E.; Gozet, T.; Kan, Y.; Kirmizibekmez, H.
    This study was designed to comparatively evaluate the phytochemical composition and antioxidant potentials of fruit extracts from five Crataegus taxa (C. monogyna, C. orientalis, C. pontica, C. rhipidophylla and C. turcicus) growing wild in the flora of Turkey. Antioxidant activities of the samples were investigated using DPPH radical scavenging, FRAP, CUPRAC and total antioxidant capacity tests. Total phenol, phenolic acid, flavonoid, and proanthocyanidin contents were measured spectrophotometrically. Additionally, the presence of some phenolic compounds in the extracts was investigated by LC-MS/MS. Furthermore, the extracts used for the antioxidant activity studies were standardized for chlorogenic acid and hyperoside by HPTLC densitometry. Among the tested extracts, C. turcicus contained the highest phenolic (398.48 +/- 0.98 GAE/g extract) and total flavonoid contents (23.87 +/- 2.74 QE/g extract) content while C. monogyna contained by far the highest total proanthocyanidin (175.65 +/- 10.59 EGCG-E/g extract), hyperoside (0.42\%) and chlorogenic acid (0.90\%) contents. Crataegus monogyna exhibited the highest antioxidant activity in FRAP, CUPRAC, and TOAC tests. Good correlation was found between the phenolic content and antioxidant parameters. This is the first report related with comparison of these five species in respect to phenolic profile and antioxidant activity. (C) 2019 SAAB. Published by Elsevier B.V. All rights reserved.
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    A practical ID-LC-MS/MS method for the most commonly analyzed steroid hormones in clinical laboratories
    (WALTER DE GRUYTER GMBH, 2019-01-01) Yesildal, Fatih; Serdar, Muhittin; Ozgurtas, Taner
    Background: Analysis of steroid hormones rapidly and reliably remains a challenge in clinical laboratories as this plays an important role in evaluation of many endocrine disorders. The aim of this study was to create a steroid profiling panel by using a liquid chromatography tandem mass spectrometry (LC-MS/MS) method which was composed of the most commonly analyzed steroid hormones in clinical laboratories. Materials and methods: Protein precipitation was performed for sample preparation. Ultra performance liquid chromatography (UPLC) system and an analytical column with C18 selectivity was chosen for chromatographic seperation. Atmospheric pressure chemical ionization (APCI) ion source was preferred for ionization, and tandem MS with triple quadrupole was used. MS scan was performed using the selected reaction monitoring mode in positive polarity. During the method validation process, test performance was evaluated for each steroid hormone, and 40 serum samples were used for method comparison with immunoassays available in our core laboratory. Results: An isotope dilution (ID)-LC-MS/MS method was developed, in which 13 steroids can be analyzed in the same run. Test performance was quite good for the 11 steroids (cortisol, DHEA, DHFAS, total testosterone, progesterone, androstenedione, 11-deoxycortisol, cortisone, corticosterone and dihydrotestosterone) while estradiol and aldosterone performance was suboptimal considering the precision and trueness. Conclusion: This ID-IC-MS/MS method would be useful in clinical laboratories, especially for the immunoassays having insufficient test performance and when checking for interferences in available immunoassays.