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Abstract

A simple and sensitive liquid chromatography-mass spectrometric (LC-MS) method has been developed and validated for the simultaneous determination of ezetimibe (EZE), atorvastatin calcium (ATO), and simvastatin (SMV) in combined dosage forms and human plasma. Successful separation of the studied drugs was achieved on a Zorbax Eclipse Plus C18 column (3.0 × 150 mm, 5 µm) using a mobile phase consisting of acetonitrile and 0.1% formic acid in water (65:35, v/v) at a flow rate of 0.5 mL min−1. Total run time was 9.3 min and diclofenac sodium was used as internal standard (IS). Positive selected ion monitoring (SIM) mode was applied where, the monitored ions were those at m/z values of 392.1, 559.3, 296.0, and 441.4 corresponding to EZE, ATO, IS, and SMV, respectively. The method was fully validated according to the ICH guidelines. The intraday and interday precision showed relative SD values not more than 1.77 and 1.99%; respectively. The limits of detection (LOD) were 0.25, 0.25, and 0.75 ng mL−1 while the limits of quantification (LOQ) were 1.25, 0.75, and 2.5 ng mL−1 for EZE, ATO, and SMV, respectively. The developed method was applied on two types of combined tablets concerning drug assay with mean percent recoveries within acceptable range. The method has been extended to the determination of the studied drugs in human plasma where, a solid phase extraction method was optimized for their extraction with percent recovery not less than 97%.

Open access

Abstract

A sweeping micellar electrokinetic chromatography (sweeping-MEKC) enrichment model was established for the determination of three chlorophenols (CPs) in cosmetics, namely, bithionol, pentachlorophenol (PCP), and 2,4,6-trichlorophenol (2,4,6-TCP). The optimum electrophoretic conditions were 20 mM NaH2PO4-80 mM sodium dodecyl sulfate (SDS) and 30% (v/v) acetonitrile (pH 2.3). The optimum on-line concentration conditions were as follows: sample matrix, 100 mM NaH2PO4; pressure injection at 20.67 kPa (3 psi) for 25 s. The linear range of bithionol, PCP, and 2,4,6-TCP are 0.20–4.00 μg mL−1, 0.10–2.00 μg mL−1, and 0.05–2.00 μg mL−1 respectively, with correlation coefficient (r) over 0.9972. The limits of detection (LOD) based on three times the signal-to-noise ratio (S/N = 3) are in the range of 0.0061–0.024 μg mL−1. Recoveries for the three CPs in powder and lotion samples are between 79.7 and 110.2% with relative standard deviation (RSD) of 1.38–5.54% and 92.2–121.3% with RSD of 0.72–6.09%, respectively. The proposed method can provide reference for the determination of trace CPs in different sample matrix.

Open access

Abstract

This study focused on developing an effective and environmentally friendly method to measure ligustrazine in rat serum by using polymer monolith micro-extraction (PMME) technique. A poly (methacrylic acid-ethylene glycol dimethacrylate) material was used to extract ligustrazine through hydrophobic and ion-exchange interaction. Qualitative and quantitative analysis was performed by a liquid chromatography and tandem mass spectrometry. After optimization of several PMME conditions, the developed method exhibited excellent extraction performance to the ligustrazine. Good linearity was acquired ranging from 10 to 2,000 ng mL−1, and the limit of detection of the proposed method was 0.14 ng mL−1. The recoveries measured by spiking three different concentrations in rat serum ranged from 82.6 to 95.3%, and excellent precision was found with relative standard deviations (RSDs) less than 8.3% for intra-day and 9.7% for inter-day, respectively. At last, the applicability of the method was further confirmed through continuous monitoring of ligustrazine in rat serum after dosing of ligustrazine tablets to rats.

Open access

Abstract

Infections with multi-drug resistant (MDR) bacteria including carbapenem-resistant Klebsiella pneumoniae are emerging worldwide but are difficult to treat with the currently available antibiotic compounds and therefore constitute serious threats to human health. This prompted us to perform a literature survey applying the MEDLINE database and Cochrane Register of Controlled Trials including clinical trials comparing different treatment regimens for infections caused by carbapenem-resistant K. pneumoniae. Our survey revealed that a combined application of antibiotic compounds such as meropenem plus vaborbactam, meropenem plus colistin and carbapenem plus carbapenem, resulted in significantly increased clinical cure and decreased mortality rates as compared to respective control treatment. However, further research on novel antibiotic compounds, but also on antibiotic-independent molecules providing synergistic or at least resistance-modifying properties needs to be undertaken in vitro as well as in large clinical trials to provide future options in the combat of emerging life-threatening infections caused by MDR bacteria.

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Akadémiai Értesítő

A Magyar Tudományos Akadémia Hivatalos Lapja

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Summary

This paper aims at describing some of the main structural and functional characteristics of two subordinate patterns, namely infinitive clauses governed by verba dicendi et sentiendi (i.e. the so-called Accusativus cum Infinitivo) and participial clauses, as they occur in the Vulgate. The characteristics of the use of the Accusativus cum Infinitivo will be interpreted within the context of the uses of this structure in other Latin texts written in different periods. In particular, and in the framework of a functional-typologi- cal approach, we will investigate word-order phenomena.

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Summary:

This paper aims at describing some of the main structural and functional characteristics of completive clauses governed by verba dicendi et sentiendi in Boethius's De consolatione philosophiae. The characteristics of the use of the Accusativus cum Infinitivo (AcI) will be analysed in comparison with the uses of other Latin authors. The data will be described on the basis of two main aspects: constituent order, and the coreferentiality of the subject of the AcI with elements in the main clause. Compared to the predominance of AcI constructions, quod-clauses show a consistent pattern and are limited to well- defined contexts. Some aspects of the use of quin and ut will also be described. Special attention will be given to the problems of syntactic and semantic interpretation of the governing verbs, which can be difficult to define clearly. This study will also set the ground for further research on the influence of Boethius's Latin model on Italo-Romance literary texts in the Middle Ages, both on the syntactic and the stilistic level.

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Summary

The copious corpus of deviations from standard Latin from Trier spans more than 800 years (50 BC–800 AD) and comprises both pagan and Christian inscriptions, the latter exclusively on tombstones. This paper points out the most salient non-standard features in the categories of phonetics, morphology, syntax and vocabulary. Most of them conform to standard Vulgar Latin, but some yield features of the inscriptions’ area, such as Western Romance (preservation of final -s, voicing intervocalic stops), Gallo-Romance (qui instead of quae, nasalisation), and the extinct Moselle Romance. A few features might reflect Gaulish substrate influence ([u] > [y], e before nasals > i, ē > ī, ō > ū, -m > -n). Clues for palatalisation and the raisings ē > ī, ō > ū are the most prominent phonetic features, the latter supporting, combined with the preservation of final -s, a renewed paradigm of nominal inflection. Morphosyntactic changes are driven by analogy and regularisations. Starting at the fringes, the erosion of case syntax ended up in a complete breakdown. Christianity fostered the recording of previously undocumented substandard features, completed the assimilation of Celtic (which pagan polytheism and the upwards mobility of Roman society had initiated) and supported the cultural integration of Germanic immigrants.

Piae memoriae Henrici Heinen, viri doctissimi

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Summary:

Centones are works that might be interpreted as bis in idem, in a positive manner, being si- multaneously a revitalisation of prior works and an independent piece, which grants a perception per se. In addition to their poetic value, a major relevance draws from the text itself, as descendant of a previous source, perfectly known not only to the author of the cento, but to the public as well, capable to appreci- ate the virtuosity. Cento nuptialis composed by Ausonius is to be considered both as Vergilian inheritance manoeuvred with poetic skill and as binomial of theory and practice, preserved in the letter addressed to Paulus.

We examine two formal aspects: the iunctura points and the entire verses taken from Vergil. The iunctura of the hemistichs seems to be occasionally generated by the presence of a certain word. Regard- ing the entire Vergilian verses, the letter addressed to Paulus states that two consecutive entire verses ineptum est: the assertion might be understood either as aiming at two consecutive verses in the source text, or as two entire verses, belonging to different parts of the source text. If the second interpretation is correct, Cento nuptialis begins inelegantly (ineptum).

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