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Využití pasivního vzorkování při analýze hormonů v pitných vodách / Application of passive sampling for the analysis of hormones in drinking waterRemerová, Martina January 2013 (has links)
The thesis focuses on the use of passive sampling during an analysis of hormones in drinkable water. In the theoretical part there are described selected passive samplers and the sample of the type of POCIS is described at fuller length. The next chapter engages with steroid hormones and an input of estrogenic hormone into the environment. The thesis contains chapters dealing with possibilities of the determination of hormones in water. It is specialized on the analysis of drinkable and surface water. In the last chapter of the theoretical part there are introduced water works where samples for an experimental assessment were collected from. The experimental part of the thesis presents the specification of the extraction of analytes and an adjustment of used device. In the thesis there are specific calibrations for individual assessment of hormones. The results of the assessment for each collection point are ordered to a well-arranged table. Increased levels of targeted estrogens were not approved in most of sampling points.
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Využití vysokoúčinných separačních metod pro analýzy biologicky aktivních látek / Analysis of biologically active compounds using high performance separation methodsAdamusová, Hana January 2017 (has links)
In the first part of this doctoral thesis, a new analytical HPLC-MS/MS method for monitoring of concentration changes of 17β-estradiol (βE2) during in vitro mouse sperm capacitation was developed. Capacitation was performed for three initial concentrations of βE2 (200, 20 and 2 μg/L). For all the concentrations a similar trend for the total unbound βE2 was observed. In general, the βE2 concentration decreased to reach its minimum and then increased again. The position of the minimum differed for the individual tested βE2 concentrations. Experimentally obtained results were subjected to the kinetic analysis. The curves fitted through the experimentally determined points displayed an autocatalytic character. For the agreement between the curves obtained by fitting through the experimental points and the theoretical calculated curves, it is necessary to assume that the first step is adsorption of βE2 onto the surface of the sperm controlled by Langmuir isotherm. The kinetic study was also used to study the effects of fluorides and aluminium fluoride complexes on the capacitation of mouse sperm. The experimental points were in very good agreement with the shape of the theoretical curves and this fact verifies the mechanism of the mouse sperm capacitation kinetics. In the second part of this work, two...
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Biološka aktivnost novosintetisanih D-seko i D-homo-estratrienskih derivata u in vivo i in vitro uslovima / Biological activity of the newly synthesized D-secoand D-homoestratriene derivatives in in vivo and in vitro experimentsJovanović-Šanta Suzana 08 October 2010 (has links)
<p>Sintetisana su nova jedinjenja, 16- i 17-supstituisani 16,17-sekoestratrienski derivati i D-homoestranski derivati, polazeći od 3-benziloksi-17-hidroksi-16,17-sekoestra-1,3,5(10)-trien-16-nitrila. Ispitana je estrogena i antiestrogena aktivnost u eksperimentima <em>in vivo</em>, antiaromatazna aktivnost <em>in vitro</em>, antioksidantna aktivnost DPPH i TBA testom, kao i antiproliferativna aktivnost prema ćelijskim linijama MCF-7 ATCC, MDA-MB-231, HT-29 i MRC-5 novosintetisanih jedinjenja.</p> / <p>Some new compounds, 16- and 17-substituted 16,17-secoestratriene derivatives, as well as D-homoestratriene derivatives, were synthesized, starting from 3-benzyloxy-17-hydroxy-16,17-secoestra-1,3,5 (10)-triene-16-nitrile. The newly synthesized compounds were tested for their <em>in vivo </em>estrogenic and antiestrogenic activity, <em>in vitro </em>antiaromatase activity, antioxidative activity by DPPH and TBA tests, as well as antiproliferative activity against MCF-7 ATCC, MDA-MB-231, HT-29 i MRC-5 cell lines.</p>
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Physiological responses of Nile tilapia (Oreochromis niloticus) after exposure to diclofenac and metoprololKeitel-Gröner, Frederike 06 March 2017 (has links)
(Oberflächen-) Gewässer weltweit sind mit geringen Mengen (ng/L bis wenige µg/L) humaner Pharmazeutika belastet. Diclofenac (DCF; nicht-steroidal, entzündungshemmend) und Metoprolol (MTP; ß-Blocker) gehören entsprechend ihres hohen Verbrauchs zu den am häufigsten gefundenen Substanzen. Deren biologische Aktivität ist nicht auf den Menschen beschränkt. Gut konservierte Enzyme innerhalb der Vertebraten legen Auswirkungen auf Nicht-Zielorganismen wie Fische nahe, die bisher in Langzeituntersuchungen mit umweltrelevanten Konzentrationen unzureichend untersucht wurden. In der vorliegenden Arbeit wurden die physiologischen Effekte von DCF und MTP auf die Nil-Tilapie (Oreochromis niloticus), einem der wichtigsten Aquakulturfische weltweit, untersucht. In vitro konnte anhand primärer Hepatozyten gezeigt werden, dass bereits umweltrelevante Konzentrationen von DCF zu einer erhöhten Genexpression verschiedener Schlüsselenzyme der Detoxifizierung führten. Nach MTP-Exposition waren die Veränderungen weniger eindeutig. Beide Substanzen induzierten die Vitellogenin Genexpression, nur DCF jedoch bereits in umweltrelevanter Konzentration. In vivo wurden in zwei Langzeit-Expositionsversuchen die physiologischen Effekte vom befruchteten Ei bis 80 Tage nach Schlupf in O. niloticus untersucht. Beide Substanzen hatte keinen Einfluss auf Schlupferfolg und Überleben, das Wachstum war nach 80 Tagen nach Schlupf leicht reduziert. Die deutlichsten Auswirkungen waren histopathologische Veränderungen der Kiemen, veränderte Genexpressionen der Gonadotropine und eine erhöhte Expression von Vitellogenin. Die Ergebnisse legen eine stärkere östrogene Aktivität von DCF im Vergleich zu MTP nahe. Zusammenfassend sind die Bedenken gegenüber den Einzelsubstanzen eher gering, negative Auswirkungen auf die Reproduktion und sich verstärkende Effekte bei zeitgleicher Exposition gegenüber DCF und MTP lassen sich jedoch nicht ausschließen und sollten im Weiteren untersucht werden. / Surface waters worldwide are contaminated with low levels (ng/L up to few µg/L) of human pharmaceuticals. Diclofenac (DCF; non-steroidal, anti-inflammatory) and metoprolol (MTP; ß-blocker) are highly consumed and therefore commonly detected. Their biological activity is not restricted to humans. Well conserved enzymes within the vertebrates suggest effects on non-target organisms such as fish, poorly studied in long-term exposure experiments using environmentally relevant concentrations. In the presented work, physiological effects of DCF and MTP on the Nile tilapia (Oreochromis niloticus), an important aquaculture fish species, were studied. Using primary hepatocytes, it was shown in vitro that environmentally relevant concentrations of DCF increased the gene expression of different key enzymes of the detoxification, while MTP exposure had a less clear effect. Both substances induced vitellogenin gene expression, but only after DCF exposure this was significantly elevated already at the environmentally relevant concentration. In vivo, two long-term exposure studies on the physiological effects from the fertilized egg until 80 days post-hatch were evaluated. Both substances did not affect hatching success and survival, while growth was slightly reduced after 80 days post-hatch. Histopathological alterations of the gills, changed gene expression patterns of the gonadotropins and induced vitellogenin gene expression were the most dominant findings. The results indicate a stronger estrogenic mode of action of DCF compared to MTP. Overall, the risk due to a single substance exposure seems to be relatively low but adverse effects on reproduction and additive effects during simultaneous exposure to DCF and MTP cannot be excluded and should be investigated further.
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Sublethal effects of chemical pollution in benthic fish species from marine Spanish waters / Efectos subletales de la contaminación química en especies de peces bentónicas de aguas españolasMartínez Gómez, Concepción 27 September 2013 (has links)
No description available.
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Hemijska, biohemijska i mikrobiološka karakterizacija Trifolium pratense L. / Chemical, biochemical and microbiological characterization of Trifolium pratense L.Vlaisavljević Sanja 19 September 2014 (has links)
<p>Hemijska karakterizacija ekstrakata <em>T. pratense </em>L. određena je LC-MS-MS, a etarskih ulja GC-MS analizom, pri čemu je identifikovano više bioaktivnih jedinjenja. Spektrofotometrijskim metodama ispitan je antioksidantni potencijal ekstrakata i etarskih ulja. Hepatoprotektivni efekat određen je na homogenatu i hemolizatu jetre laboratorijskih miševa. Budući da ova biljka ima visok sadržaj izoflavona, određena je <br />estrogena, antiestrogena aktivnost, kao i citotoksičnost ekstrakata. Antimikrobna <br />aktivnosta ekstrakata i etarskih ulja ispitana je na šest bakterijskih sojeva. Ekstrakti i etarska ulja su bili umereno aktivni u pogledu bioloških aktivnosti, osim u slučaju antimikrobne aktivnosti koju nije pokazao nijedan ispitivani uzorak.</p> / <p>The chemical characterization of <em>T. pratense</em> extracts was determined by LC-MS-MS, and the essential oils of the GC-MS analysis, wherein the various bioactive compounds were identified. Antioxidant potential of extracts and essential oils was tested by spectrophotometric methods. Hepatoprotective effect was determined in haemolysate and liver homogenate of laboratory mice. Estrogen, antiestrogen activity, as well as the cytotoxicity of the extracts were determined due to the high content of isoflavones. Antimicrobial activity of extracts and essential oils was investigatied on six bacterial strains. Essential oils and extracts were moderately active in terms of biological activity, except in the case of antimicrobial activity where none of the extracts were active against tested bacterial strains.</p>
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Detection of aeromonas species in relation to the occurrence of estrogens and testosterone in various water resources in Limpopo Province, South Africa and Lusaka, ZambiaManavhela, Murendeni 18 May 2019 (has links)
MSc (Microbiology) / Department of Microbiology / Background: The occurrence of microorganisms and endocrine disrupting chemicals
(EDCs) in water poses a serious concern due to their effects on humans, animals and
environment. In recent years, EDCs have been increasingly reported in rivers that
receive large amounts of wastewater effluents. Of all the EDCs, natural and synthetic
hormones are among those that are recognized for their potential to mimic or interfere
with normal hormonal functions of humans and animals. The present study aimed at
assessing the occurrence of these hormones in relation to the molecular diversity of
Aeromonas and evaluating the resistance of Aeromonas to antibiotics as well as to
assess anti-bacterial activity of two selected traditional medicinal plants.
Methods: Wastewater, water and fish samples were collected from various sources
(rivers, wastewater treatment plants, taps, and dams) for the detection of hormones
and isolation of Aeromonas species. The analysis of hormones from various organs
of the fish and from water samples was conducted, after extraction using enzymelinked
immunosorbent assays (ELISA). Different types of hormones including Estriol,
Estradiol, Ethinylesradiol and Testosterone were detected, and their concentrations
determined. Aeromonas spp were isolated rom the samples using microbiological
methods and Conventional PCR was used for genotyping as well as for detection of
the beta-lactamase genes. Kirby-bauer method was used to determine the
susceptibility profiles of Aeromonas to different antibiotics. Microdilution assay was
used to determine the Anti-bacterial activity of the plant (Annoniceae and Zornia
milneana) extracts against Aeromonas species.
Results: A total of 144 samples were collected from 23 different locations in two
countries: South Africa and Zambia. These included wastewater and treated
wastewater, River water, fish and tap water. 17α-ethinylestradiol (EE2) was detected
in most of the samples (92.7%) with concentrations varying from 0.59 ng/ml to 65
ng/ml. The hormones were also detected from drinking water, with testosterone
detected at high concentrations of up to 140 ng/ml in tap water. Most sewage treatment
plants were not able to remove the EE2 from the wastewater as the concentration of
this hormone in the final effluent was almost always higher than that in the influent.
These homones were also detected in drinking water at high concentrations of up to
53.49 ng/ml in the tap water for EE2 and 1777 ng/ml for E2. The overall detection of
Aeromonas species in the samples was 84.5%. A. caviae was the most prevalent
species accounting for 73.6%, followed by A. veronii with 64.6%. The bacteria were
completely resistant to cefuroxime accounting for 100% resistance. Aeromonas
isolates also showed high resistance to trimethroprim (88.7% for A. hydrophila),
cefazolin (highest 97.8% for A. cavie), and ceftazidime (83.9% for A. sobria). TEM was
the most prevalent beta-lactamase gene with detection rate of 87%. All isolates lacked
the presence of the CTX-M3 gene. Also, wastewater had the highest prevalence of A.
veronni and A. caviae accounting for 87.5% and 82.5% respectively. Multiple antibiotic
resistance was also observed with the Aeromonas isolates being resistant to up to 11
antibiotics. High prevalence of 77.1% of Aeromonas hydrophila was observed in the
presence of ethinylestradiol (EE2). Aeromonas veronii and Aeromonas caviae were
the most predominant species in the presence of total estriol, A. veronii had a
prevalence of 57.1% and A. caviae had a prevalence of 52.8%. Aeromonas hydrophila
and Aeromonas caviae had the lower prevalence in the presence of hormones with
the percentages of 26.1% and 27.8% respectively. The methanol extracts of both
Zornia milneana and Annona species showed good activity against the Aeromonas
spp with the lowest MIC of 0.078 mg/ml. Ethyl acetate extracts were the least effective.
Conclusion: This study has shown high occurrence of steroid hormones in all types
of environmental samples tested. These included tap water, river water, wastewater
and fish both in Zambia and South Africa. Therefore, steroid hormones constitute and
important health problem in the Southern African Sub-Region. The incapacity of the
wastewater treatment plants to remove EE2 is an important problem that needs to be
tackled immediately. The prevalence of Aeromonas species is very high in our
environmental water as well as in drinking water, with the highest prevalence observed
in fish and wastewater. It was also revealed that there is relationship between steroid
hormones and Aeromonas species, with the hormones supporting the growth of
Aeromonas species. The presence of beta-lactamase genes which causes
Aeromonas to be resistant to antibiotics was also noted. Methanol extracts of Zornia
milneana and Annona spp were the most effective against Aeromonas spp and could
serve as primary sources for the isolation of lead compounds. / NRF
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