Ivo Schmerold

Chemical characterization by GC-MS and in vitro activity against Candida albicans of volatile fractions prepared from Artemisia dracunculus, Artemisia abrotanum, Artemisia absinthium and Artemisia vulgaris

BackgroundA large number of essential oils is reported to have significant activity against Candida albicans. But the different chemical composition influences the degree of their activity. The intention of this study was to investigate the chemical composition and the activity against Candida albicans of volatile oils obtained from Artemisia dracunculus, A. abrotanum, A. absinthium and A. vulgaris (Asteraceae). The aim of the study was to identify new chemical compounds that have effect against C. albicans.The essential oils were obtained by hydrodistillation or extraction with dichloromethane (a new procedure we developed trying to obtain better, more separated compounds) from air dried above ground plant material and analyzed by GC-MS. Additionally commercial essential oils from the same species were tested. The Candida albicans inhibition studies were carried out by the paper disc diffusion method.ResultsThe essential oils shared common components but presented differences in composition and showed variable antifungal activity. Davanone and derivatives thereof, compounds with silphiperfolane skeleton, estragole, davanone oil, β-thujone, sabinyl acetate, herniarin, cis-chrysanthenyl acetate, 1,8-cineol, and terpineol were the main components of Artemisia volatiles.ConclusionsAmong the volatile fractions tested those from A. abrotanum containing davanone or silphiperfolane derivatives showed the highest antifungal activity. The in vitro tests revealed that the Artemisia oils are promising candidates for further research to develop novel anti-candida drugs.

Induction of rat liver O6-alkylguanine-DNA alkyltransferase by bleomycin.

Alkyl adducts at the O6-position of guanine constitute promutagenic DNA lesions likely to be involved in the initiation of malignant transformation. They can be removed by a cellular acceptor protein termed O6-alkylguanine-DNA alkyltransferase (AT). In rat liver this repair enzyme can be induced by a variety of hepatotoxins, partial hepatectomy and X-irradiation. This paper describes a stimulation of the hepatic AT by treatment of rats with the radiomimetic agent, bleomycin. Induction of AT is dose-dependent up to 20 mg bleomycin/kg and appears to level off with higher doses. Enhancement of O6-meG repair is detectable within 24 h after a single i.p. injection. Maximum AT induction was reached after 6 days and amounted to 350% of the control levels. The enhancement of AT activity is not associated with acute liver injury and initially coincides with an inhibition of [3H]deoxythymidine incorporation into hepatic DNA. This indicates that AT induction in rat liver is not necessarily dependent on tissue necrosis with increased cell replication. Since bleomycin does not produce DNA lesions recognized and repaired by the AT, the hypothesis is entertained that AT induction by these agents is part of a concerted reaction to radiation-type DNA damage.

Cabin air temperature of parked vehicles in summer conditions: life-threatening environment for children and pets calculated by a dynamic model

In vehicles that are parked, no ventilation and/or air conditioning takes place. If a vehicle is exposed to direct solar radiation, an immediate temperature rise occurs. The high cabin air temperature can threaten children and animals that are left unattended in vehicles. In the USA, lethal heat strokes cause a mean death rate of 37 children per year. In addition, temperature-sensitive goods (e.g. drugs in ambulances and veterinary vehicles) can be adversely affected by high temperatures. To calculate the rise of the cabin air temperature, a dynamic model was developed that is driven by only three parameters, available at standard meteorological stations: air temperature, global radiation and wind velocity. The transition from the initial temperature to the constant equilibrium temperature depends strongly on the configuration of the vehicle, more specifically on insulation, window area and transmission of the glass, as well as on the meteorological conditions. The comparison of the model with empirical data showed good agreement. The model output can be applied to assess the heat load of children and animals as well as temperature-sensitive goods, which are transported and/or stored in a vehicle.

Development and evaluation of a system to assess antimicrobial drug use in farm animals: results of an Austrian study

The objective of this study was to develop and evaluate a feasible system for the collection of antimicrobial consumption data in farm animals in Austria. An electronic registry of all antibacterial pharmaceuticals approved in Austria for use in farm animals was created, listing product name, marketing authorisation number, active ingredient, package unit, strength, target species (cattle, swine, poultry), route of administration and indication, and allocating the corresponding code of the World Health Organization (WHO) Anatomical Therapeutic Chemical classification system for veterinary medicines to each substance (ATCvet-code). Different units (absolute quantities, animal daily dose, assumed daily product dose) enabled computation of the amounts of antimicrobials as pure substance, the constituents of a veterinary medicinal product, or the number of administrations. Two data collection systems were evaluated: (1) data transfer from the management software of veterinary practices or the Austrian Poultry Health Service; and (2) on-site data collection by manual data input from prescription records into an electronic registry. A total of 14,267 data sets provided by 18 practices were documented during the period January 2008 to March 2010. The total weight of active substances reported amounted to more than 5.4 tonnes for all species studied. The systems proved suitable for routine data acquisition and were considered in a recent national regulation on the surveillance of sale and consumption of veterinary antimicrobial substances.

Unterschiede zwischen Milz-und Thymuszellen der Ratte in der Wirkung von Ethidiumbromid auf die unprogrammierte DNA-Synthese (DNA-Reparatursynthese) und die Nucleoidsedimentation / Differences between Rat Splenic and Thymic Cells with Respect to the Effects of Ethidium Bromide on the Unsheduled DNA Synthesis (DNA Repair Synthesis) and the Nucleoid Sedimentation

To get further insight into the causes of differences between rat splenic and thymic cells with regard to DNA repair synthesis, scheduled (SDS) and unscheduled (UDS) DNA synthesis as well as nucleoid sedimentation of the cells were investigated under the influence of ethidium bromide (EB, 1 -1000 μg/ml). - At concentrations of ≳ 25 μg/ml, EB inhibited SDS of both cell species and UDS of thymic cells; much higher additions of the drug (>200 μg/ml) were needed to diminish UDS of splenic cells, lower EB-concentrations (25- 175 μg/ml) stimulating the UDS of the splenic cell preparation. - The sedimentation rate of splenic and thymic cell nucleoids within neutral sucrose gradients had a biphasic dependence on the EB-concentrations. As compared to thymic cells however, preincubation of splenic cells with 50-250 μg EB/ml resulted in a significant greater (15-30 percent) sedimentation distance. - The results suggest that a relationship exists between the stimulation of UDS and the ability of cells to establish a greater DNA compactness in the presence of EB.

Position Paper : EUFEPS Network on Veterinary Medicines Initiative: An interdisciplinary forum to support Veterinary Pharmacology and promote the development of new pharmaceuticals for Animal Health

Veterinary medicines account for a substantial portion of the production, sale, and consumption of medicines in Europe, and probably world-wide. This calls our attention to the fact that only healt ...

The legal foundation of the production and use of herd-specific vaccines in Europe

In veterinary medicine, herd-specific vaccines are primarily used in farm animals if traditional vaccines are either unavailable or do not perform as expected. As autogenous products, these vaccines are exempt from Directive 2001/82/EC, and therefore the production and use of herd-specific vaccines are regulated differently in each member state of the European Union (EU). This study is an overview of the diverse legal statuses of herd-specific vaccines among European countries. The study was conducted by analyzing legal documents, tailored questionnaires answered by subject-related authorities from sixteen European countries, and related literature. These analyses revealed that tremendous heterogeneity exists with respect to the legal requirements for the production and use of herd-specific vaccines among the countries that were examined. In particular, certain countries have detailed and precise regulations for these vaccines, whereas the legislation regarding these vaccines is vague or even nonexistent in other nations. The implementation of standardized definitions, guidelines for vaccine use in the field, and regulations for vaccine production are essential prerequisites for achieving legal consistency across Europe. These measures would also help countries enact pertinent national legislation with less divergence regarding the production and use of herd-specific vaccines and ensure the existence of comparable safety and quality standards for these vaccines among European countries.

[DNase II activation in rat liver in the course of acute diethylnitrosamine-induced damage (author's transl)].

Single oral treatment of rats with acutely toxic doses of diethylnitrosamine (DENA) caused a temporary increase of liver-deoxyribonuclease II (DNase II) in homogenate, parenchymal cell, and diverse cell compartments. Highest stimulation resulted in nuclear fraction and cytosol. Due to largely congruent in vitro features, it was suggested that the normal as well as the DENA-activated DNase II were identical. Non-ionic detergents enhanced the enzyme activity only in control samples to a relatively small extent. Suitable conditions of reaction provided, the activation was suppressed by cycloheximide. The results indicated different mechanisms of DNase II activation in the course of an acute DENA-intoxication: 1. release of structurally bound DNase II fractions into cytosol; 2. induction of the enzyme and/or of an effector; 3. enhancement of the nucleus bound enzyme activity by translocation of activated DNase II from cytosolic to nuclear area.ZusammenfassungDie einmalige per-orale Verabreichung akut toxischer Dosen Diäthylnitrosamin (DÄNA) an Ratten führte zu einer temporären Erhöhung der Leber-Desoxyribonuklease II (DNase II) in Homogenat, Parenchymzelle und mehreren Zellkompartimenten. Die höchste Stimulierung ergab sich in Zellkernfraktion und Zytosol. Die weitgehende Übereinstimmung in den untersuchten in-vitro-Eigenschaften ließ die normale und DÄNA-aktivierte DNase II identisch erscheinen. Nichtionische Detergentien erhöhten nur in Kontrollproben in relativ geringem Ausmaß die Enzymaktivität. Unter geeigneten Versuchsbedingungen war die Aktivierung durch Cycloheximid unterdrückbar. Die Befunde wiesen auf verschiedene DNase II-Aktivierungsmechanismen in der Folge einer akuten DÄNA-Intoxikation hin: 1. Freisetzung strukturgebundener DNase II-Anteile in das Zytosol; 2. Induktion des Enzymes und/oder eines Effektors; 3. Erhöhung der zellkernständigen Enzymaktivität durch Translokation aktivierter DNase II aus dem zytoplasmatischen in den nukleären Bereich.