Browse

You are looking at 1 - 10 of 81,531 items for

  • Refine by Access: All Content x
Clear All

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

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.

read more

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.

Full access

Abstract

By a broad-range PCR, we detected a novel herpesvirus (HV) in the specimen of a wels catfish (Silurus glanis) presenting disseminated, carp pox-like dermal lesions all over its body. The sequence analysis of the 463-bp PCR product from the viral DNA polymerase gene indicated the presence of a hitherto unknown virus, a putative member of the family Alloherpesviridae in the sample. Another PCR, targeting the terminase gene of fish HVs, provided an additional genomic fragment of over 1,000 bp. Surprisingly, the sequence of a co-amplified, off-target PCR product revealed its origin from a putative gene homologous to ORF87 and ORF45 of cyprinid HVs and anguillid herpesvirus 1 (AngHV-1), respectively. With specific primers, designed according to the genomic maps of the cyprinid and anguillid HVs, a genomic fragment of 15 kb was also amplified and sequenced by primer walking. In phylogeny inferences, based on several genes, the putative wels catfish HV clustered closest to various cyprinid HVs or to AngHV-1. The novel virus, named as silurid herpesvirus 2, represents a distinct species in the genus Cyprinivirus. However, its association with the skin disease remains unclear.

Open access

A 18F-FDG-PET/CT helye az ismeretlen eredetű láz diagnosztikai algoritmusában

Diagnostic value of 18F-FDG PET/CT in fever of unknown origin

Orvosi Hetilap
Authors:
Emőke Šteňová
,
Pavol Povinec
,
Lenka Tarabčáková
,
Zoltán Szekanecz
, and
Szilvia Szamosi

Az ismeretlen eredetű láz gyakori differenciáldiagnosztikai probléma az orvostudományban. A kórkép első definiálása óta eltelt több mint 60 év, és a diagnosztikai eljárások állandó fejlődése és tökéletesítése ellenére továbbra is kihívást jelent a kezelőorvos számára a differenciáldiagnosztika és a megfelelő terápia megválasztása. Az orvosi szakirodalom legalább 200 betegséget tart számon, amely ismeretlen eredetű lázzal manifesztálódhat, és ezek igen széles klinikai spektrumot ölelnek fel. A hospitalizációt igénylő betegek esetében hozzávetőlegesen 1,5–3%-ban van jelen ismeretlen eredetű láz. Az elmúlt évtizedekben többször változott nemcsak az ismeretlen eredetű láz definíciója, de az ajánlott kivizsgálási protokoll is. A pozitronemissziós tomográfia a legmodernebb képalkotó eljárások közé tartozik, s nagyban hozzájárul a bonyolult esetek összefüggéseinek feltárásához és a helyes diagnózis felállításához. A jelen közlemény célja, hogy átfogó képet nyújtson az ismeretlen eredetű lázat kiváltó betegségekről, a leggyakrabban használt diagnosztikai algoritmusokról, valamint rávilágít a pozitronemissziós tomográfia fontos szerepére e betegségek okainak feltárásában. Orv Hetil. 2022; 163(49): 1935–1942.

Open access

Az ischaemiás stroke kockázati tényezői a dystrophia myotonica 1-es típusában

Risk factors for ischaemic stroke in myotonic dystrophy type 1

Orvosi Hetilap
Authors:
Dávid Varga
,
Brigitta Perecz
,
Andrea Sípos
,
Dalma Jedlicska
, and
Endre Pál

Bevezetés: A dystrophia myotonica a leggyakoribb felnőttkori, autoszomális domináns módon öröklődő izombetegségek csoportjába tartozik. Mindkét klinikai altípusának jellemzője a ’splicing’ mechanizmus zavara okán kialakult, kiterjedt mRNS- és következményes fehérje-funkciózavar. Mindez multiszisztémás betegség megjelenését idézi elő, az izomérintettségen túl szürke hályog, szívritmuszavar, csökkent légzési kapacitás, szénhidrát- és zsíranyagcsere-zavar, endokrinológiai eltérések és kognitív deficit kialakulásával. Több tanulmány említi a dystrophia myotonica 1-es típusában megfigyelhető nagyobb stroke-kockázatot. Célkitűzés: Vizsgálatunkban a Klinikánk gondozásában álló, a dystrophia myotonica 1-es típusában szenvedő 31 beteg részletes vizsgálatát végeztük el az ischaemiás stroke kockázati tényezőinek feltérképezése céljából. Módszer: A betegek kórtörténetének részletes áttekintését a Klinikánk laboratóriumában végzett vizsgálatok, valamint arteria (a.) carotis ultrahangvizsgálat követte. Eredmények: Betegeinknél atherogen dyslipidaemia, normális a. carotis intima és media vastagság volt azonosítható, ugyanakkor nagy arányban igazolódott supraventricularis szívritmuszavar. Megbeszélés: A nemzetközi irodalmi adatokkal egybehangzóan ezen vizsgálat is támogathatja azt a feltevést, mely szerint a dystrophia myotonica 1-es típusában észlelhető nagyobb ischaemiás stroke rizikó hátterében a leginkább releváns kockázati tényező a supraventricularis ritmuszavar (pitvarfibrilláció és ’flutter’) lehet. Következtetés: A dystrophia myotonica 1-es típusában szenvedő betegpopuláció hosszmetszeti követése során kiemelt figyelmet kell fordítanunk a kardiológiai gondozásra is. Orv Hetil. 2022; 163(49): 1962–1966.

Open access