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Abstract

The retention behaviour of scopolamine (hyoscine) and its related compounds (norhyoscine, atropine, homatropine, and noratropine) was investigated on the silica-based HPLC stationary phase. The retention of investigated tropane alkaloids was interpreted by using the Soczewiński-Wachtmeister equation. A high correlation between the retention parameter (log k) and lipophilicity (log P) (R = 0.9923) confirms the significant influence of hydrophobic interactions on the retention behaviour of the aforementioned compounds. It was found that by increasing the acetonitrile fraction, a decrease in retention of the more polar epoxide derivatives (scopolamine, norhyoscine) and an increase in retention of the more lipophilic derivatives (atropine, noratropine, homatropine) is obtained. The best separation of the tropane alkaloids was achieved by a simple procedure that involved a mobile phase composed of acetonitrile and 40 mM ammonium acetate/0.05% TEA, pH 6.5; 50:50 v/v. Selected conditions were assumed for the determination of scopolamine hydrochloride in the eye drops (Scopolamini hydrobromidum 0.25%). The method was validated and it was found as selective, sensitive, precise, accurate, and robust for the further qualitative analysis of the scopolamine-related compounds.

Open access

Chalcocondyles Latinus •

Konrad Clauser's translation of Chalkokondyles

Acta Antiqua Academiae Scientiarum Hungaricae
Author:
Tamás Mészáros

Abstract

Zurich scholar Konrad Clauser's translation of Chalkokondyles was printed in 1556 at Oporinus' publishing house in Basel. The present paper reconstructs the circumstances of the formation of that translation, provides a detailed account of the publication, attempts to establish which manuscript may have served as the basis for the translation, and presents an outline of the immediate reception of the translation.

Open access

Abstract

Aim

This study examines narratives describing complex psychedelic experiences after smoking N,N-dimethyltryptamine.

Methods

The narrative accounts examined here were gathered from a variety of online sites and analyzed in order to discover themes, categories and patterns in the phenomenon of the resulting psychedelic experiences.

Results

Subjects reported seeing complex and unusual visual and synesthetic phenomena, leaving this world and entering into extraordinary places, encounters with a variety of strange entities, interactions with unusual objects and a wide variety of powerful feelings. The general categories of Places, Objects, Entities and Feelings were found in the phenomena experienced by people who smoked N,N-Dimethyltryptamine. These provided a framework within which more detailed subcategories were found and the range of most frequent to least frequent experiences were identified.

Discussion

While DMT experiences are commonly described by people smoking N,N-dimethyltryptamine as indescribable, unique to everyone and taking place in a single domain called Hyperspace or the Hyperdimension, this research found distinct subcategories of frequently visited Places as well as frequently encountered Entities, Objects and Feelings. From these a more comprehensive understanding can be developed of the unusual and profound experiences resulting from inhalation of N,N,-Dimethyltryptamine.

Open access

Abstract

In this study, we report the systematic approach for characterization of two major degradant impurities, which are not listed in any compendia and were formed during the stability studies of Dihydroergotamine mesylate injection (DHE). An ion-pair UPLC chromatographic method was developed to quantify the related substances present in the DHE injection drug product. The same was used to monitor the impurity profiling during its stability. The two unknown impurities were observed at RRT about 0.08 (Impurity-1) and RRT about 0.80 (Impurity-5) and found to be significantly increasing on stability. Forced degradation studies revealed the nature of the impurity and conditions required for enriching them. A Mass compatible HPLC method was developed to quantify only these two impurities using 25% ammonia and formic acid in water. Their mass numbers were identified using LC MS/MS with triple quadruple mass spectrometer coupled with a HPLC. These two impurities were then isolated from enriched products using preparative HPLC. These impurities were then characterized using Mass and NMR analysis along with Q-TOF elemental analysis.

Open access

Proud to share that this year, Zsolt Demetrovics , founding editor-in-chief of our open access Q1 title, Journal of Behavioural Addictions , was ranked as a Highly Cited Researcher in the field of Psychiatry and Psychology by Clarivate.

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Summary

Human cysticercosis is caused by the ingestion of eggs of the pork tapeworm (Taenia solium) (1). The ingested eggs evolve into onconspheres that cross the intestinal mucous membrane, distributing themselves to the muscles, making man their intermediate host (3).

The condition of rare systemic infestation is known as disseminated cysticercosis.

Open access

Abstract

The European Union, while acknowledging the pitfalls of problematic consumer markets, seems largely unwilling to deviate from an inflexible standard of consumer behaviour based on the ideal of the average consumer as a reasonably well-informed and observant market participant. The article aims to contrast this high consumer standard with the alternatives offered by the vulnerable consumer concept. The first part of the article deals with the notion of the average consumer as defined in European Union law and its interpretation by the European Court of Justice, particularly in cases concerning problematic markets. This is followed by a brief analysis of two potential interpretations of consumer vulnerability developed in the consumer protection literature. The final chapter examines in more detail the appearance of a singular major exception to the average consumer concept within the European Union consumer protection regime: the narrow scope of consumers acknowledged as ‘particularly vulnerable.’

Open access
Acta Chromatographica
Authors:
Vladimir Dobričić
,
Jelena Savić
,
Tihomir Tomašič
,
Martina Durcik
,
Nace Zidar
,
Lucija Peterlin Mašič
,
Janez Ilaš
,
Danijel Kikelj
, and
Olivera Čudina

Abstract

Bacterial DNA gyrase and topoisomerase IV control the topological state of DNA during replication and represent important antibacterial drug targets. To be successful as drug candidates, newly synthesized compounds must possess optimal lipophilicity, which enables efficient delivery to the site of action. In this study, retention behavior of twenty-three previously synthesized dual DNA gyrase and topoisomerase IV inhibitors was tested in RP-HPLC system, consisting of C8 column and acetonitrile/phosphate buffer (pH 5.5 and pH 7.4) mobile phase. logD was calculated at both pH values and the best correlation with logD was obtained for retention parameter φ0, indicating that this RP-HPLC system could be used as an alternative to the shake-flask determination of lipophilicity. Subsequent QSRR analysis revealed that intrinsic lipophilicity (logP) and molecular weight (bcutm13) have a positive, while solubility (bcutp3) has a negative influence on this retention parameter.

Open access

Abstract

Since the Maastricht Treaty, two questions remain: what is the EU, and is there such as thing as an EU identity? Because of its specific nature, and in view of the political accession criteria, it seems there is an EU political identity. Consequently, the purpose of this article is to evaluate whether this EU political identity has had an impact on Member States' constitutional identity: because they were the latest countries to accede to the EU, but also because they were under a specific monitoring process, Bulgaria and Romania are the best examples of an EU influence, but only of a limited one.

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