Application of micronucleus in vitro assay to micropollutants in river water

1997 ◽  
Vol 35 (8) ◽  
pp. 9-13 ◽  
Author(s):  
Youn-Son Chung ◽  
Kazuhiro Ichikawa ◽  
Hideo Utsumi

To determine the genotoxicity of river water towards mammalian cells, we applied Micronucleus in vitro test using mammalian cells to the samples taken from river Tamagawa located between Tokyo and Kanagawa prefecture. Water samples were condensed by Sep-pak cartridges and extracted by dichloromethane and methanol. Positive genotoxicity was observed in methanol extracts from sampling stations of Hinobashi and Marukobashi, while no dichloromethane extracts showed genotoxicity, suggesting that polar genotoxic micropollutants may be contained in the water of Tamagawa, at least in its down-stream. Significantly high mutagenicity also detected from Hinobashi and Marukobashi by Ames mutagenicity test using Salmonella Typhimurium, and some difference was obtained in sensitivity between the two methods. This may arise from the difference in species used, that is, mammalian cells in micronucleus test and bacteria in Ames mutagenicity test.

2017 ◽  
Vol 25 (5) ◽  
pp. 4011-4011
Author(s):  
Eva-Maria Prantl ◽  
Meike Kramer ◽  
Carsten K. Schmidt ◽  
Martina Knauer ◽  
Stefan Gartiser ◽  
...  

2016 ◽  
Vol 25 (5) ◽  
pp. 3996-4010 ◽  
Author(s):  
Eva-Maria Prantl ◽  
Meike Kramer ◽  
Carsten K. Schmidt ◽  
Martina Knauer ◽  
Stefan Gartiser ◽  
...  

2004 ◽  
Vol 151 (3) ◽  
pp. 397-406 ◽  
Author(s):  
C Grossmann ◽  
T Scholz ◽  
M Rochel ◽  
C Bumke-Vogt ◽  
W Oelkers ◽  
...  

BACKGROUND: Glucocorticoids (GCs) are commonly used for long-term medication in immunosuppressive and anti-inflammatory therapy. However, the data describing gluco- and mineralo-corticoid (MC) properties of widely applied synthetic GCs are often based on diverse clinical observations and on a variety of in vitro tests under various conditions, which makes a quantitative comparison questionable. METHOD: We compared MC and GC properties of different steroids, often used in clinical practice, in the same in vitro test system (luciferase transactivation assay in CV-1 cells transfected with either hMR or hGRalpha expression vectors) complemented by a system to test the steroid binding affinities at the hMR (protein expression in T7-coupled rabbit reticulocyte lysate). RESULTS AND CONCLUSIONS: While the potency of a GC is increased by an 11-hydroxy group, both its potency and its selectivity are increased by the Delta1-dehydro-configuration and a hydrophobic residue in position 16 (16-methylene, 16alpha-methyl or 16beta-methyl group). Almost ideal GCs in terms of missing MC effects, as defined by our in vitro assay, are therefore prednylidene, budesonide, beclomethasone and betamethasone.The MC potency of a steroid is increased by a 9alpha- or a 6alpha-fluoro substituent. A hydrophilic substituent in position 16 (like 16-hydroxylation in triamcinolone) decreases both MC and GC properties. As no substituent that leads to an isolated reduction of GC activity could be characterized in our experiments, 9alpha-fluorocortisol, the most frequently used steroid for MC substitution, seems to be the best choice of available steroids for this purpose.


1980 ◽  
Vol 44 (01) ◽  
pp. 006-008 ◽  
Author(s):  
D Bergqvist ◽  
K-E Arfors

SummaryIn a model using an isolated rabbit mesenteric preparation microvessels were transected and the time until haemostatic plugs formed was registered. Perfusion of platelet rich plasma gave no haemostasis whereas whole blood did. Addition of chlorpromazine or adenosine to the whole blood significantly prolonged the time for haemostasis, and addition of ADP to the platelet rich plasma significantly shortened it. It is concluded that red cells are necessary for a normal haemostasis in this model, probably by a combination of a haemodynamic and ADP releasing effect.The fundamental role of platelets in haemostatic plug formation is unquestionable but there are still problems concerning the stimulus for this process to start. Three platelet aggregating substances have been discussed – thrombin, adenosine diphosphate (ADP) and collagen. Evidence speaking in favour of thrombin is, however, very minimal, and the discussion has to be focused on collagen and ADP. In an in vitro system using polyethylene tubings we have shown that "haemostasis" can be obtained without the presence of collagen but against these results can be argued that it is only another in vitro test for platelet aggregation (1).To be able to induce haemostasis in this model, however, the presence of red blood cells is necessary. To further study this problem we have developed a model where haemostatic plug formation can be studied in the isolated rabbit mesentery and we have briefly reported on this (2).Thus, it is possible to perfuse the vessels with whole blood as well as with platelet rich plasma (PRP) and different pharmacological agents of importance.


2021 ◽  
Vol 9 (3) ◽  
pp. 478
Author(s):  
Ersilia Vita Fiscarelli ◽  
Martina Rossitto ◽  
Paola Rosati ◽  
Nour Essa ◽  
Valentina Crocetta ◽  
...  

As disease worsens in patients with cystic fibrosis (CF), Pseudomonas aeruginosa (PA) colonizes the lungs, causing pulmonary failure and mortality. Progressively, PA forms typical biofilms, and antibiotic treatments determine multidrug-resistant (MDR) PA strains. To advance new therapies against MDR PA, research has reappraised bacteriophages (phages), viruses naturally infecting bacteria. Because few in vitro studies have tested phages on CF PA biofilms, general reliability remains unclear. This study aimed to test in vitro newly isolated environmental phage activity against PA isolates from patients with CF at Bambino Gesù Children’s Hospital (OBG), Rome, Italy. After testing in vitro phage activities, we combined phages with amikacin, meropenem, and tobramycin against CF PA pre-formed biofilms. We also investigated new emerging morphotypes and bacterial regrowth. We obtained 22 newly isolated phages from various environments, including OBG. In about 94% of 32 CF PA isolates tested, these phages showed in vitro PA lysis. Despite poor efficacy against chronic CF PA, five selected-lytic-phages (Φ4_ZP1, Φ9_ZP2, Φ14_OBG, Φ17_OBG, and Φ19_OBG) showed wide host activity. The Φ4_ZP1-meropenem and Φ14_OBG-tobramycin combinations significantly reduced CF PA biofilms (p < 0.001). To advance potential combined phage-antibiotic therapy, we envisage further in vitro test combinations with newly isolated phages, including those from hospital environments, against CF PA biofilms from early and chronic infections.


1996 ◽  
Vol 24 (3) ◽  
pp. 325-331
Author(s):  
Iain F. H. Purchase

The title of this paper is challenging, because the question of how in vitro methods and results contribute to human health risk assessment is rarely considered. The process of risk assessment usually begins with hazard assessment, which provides a description of the inherent toxicological properties of the chemical. The next step is to assess the relevance of this to humans, i.e. the human hazard assessment. Finally, information on exposure is examined, and risk can then be assessed. In vitro methods have a limited, but important, role to play in risk assessment. The results can be used for classification and labelling; these are methods of controlling exposure, analogous to risk assessment, but without considering exposure. The Ames Salmonella test is the only in vitro method which is incorporated into regulations and used widely. Data from this test can, at best, lead to classification of a chemical with regard to genotoxicity, but cannot be used for classification and labelling on their own. Several in vitro test systems which assess the topical irritancy and corrosivity of chemicals have been reasonably well validated, and the results from these tests can be used for classification. The future development of in vitro methods is likely to be slow, as it depends on the development of new concepts and ideas. The in vivo methods which currently have reasonably developed in vitro alternatives will be the easiest to replace. The remaining in vivo methods, which provide toxicological information from repeated chronic dosing, with varied endpoints and by mechanisms which are not understood, will be more difficult to replace.


Author(s):  
Muhammad Faris Adrianto ◽  
Febri Annuryanti ◽  
Clive G. Wilson ◽  
Ravi Sheshala ◽  
Raghu Raj Singh Thakur

AbstractThe delivery of drugs to the posterior segment of the eye remains a tremendously difficult task. Prolonged treatment in conventional intravitreal therapy requires injections that are administered frequently due to the rapid clearance of the drug molecules. As an alternative, intraocular implants can offer drug release for long-term therapy. However, one of the several challenges in developing intraocular implants is selecting an appropriate in vitro dissolution testing model. In order to determine the efficacy of ocular implants in drug release, multiple in vitro test models were emerging. While these in vitro models may be used to analyse drug release profiles, the findings may not predict in vivo retinal drug exposure as this is influenced by metabolic and physiological factors. This review considers various types of in vitro test methods used to test drug release of ocular implants. Importantly, it discusses the challenges and factors that must be considered in the development and testing of the implants in an in vitro setup. Graphical abstract


1995 ◽  
Vol 23 (1) ◽  
pp. 61-73
Author(s):  
Coenraad Hendriksen ◽  
Johan van der Gun

In the quality control of vaccine batches, the potency testing of inactivated vaccines is one of the areas requiring very large numbers of animals, which usually suffer significant distress as a result of the experimental procedures employed. This article deals with the potency testing of diphtheria and tetanus toxoids, two vaccines which are used extensively throughout the world. The relevance of the potency test prescribed by the European Pharmacopoeia monographs is questioned. The validity of the potency test as a model for the human response, the ability of the test to be standardised, and the relevance of the test in relation to the quality of the product are discussed. It is concluded that the potency test has only limited predictive value for the antitoxin responses to be expected in recipients of these toxoids. An alternative approach for estimating the potency of toxoid batches is discussed, in which a distinction is made between estimation of the immunogenic potency of the first few batches obtained from a seed lot and monitoring the consistency of the quality of subsequent batches. The use of animals is limited to the first few batches. Monitoring the consistency of the quality of subsequent batches is based on in vitro test methods. Factors which hamper the introduction and acceptance of the alternative approach are considered. Finally, proposals are made for replacement, reduction and/or refinement (the Three Rs) in the use of animals in the routine potency testing of toxoids.


2006 ◽  
Vol 69 (12) ◽  
pp. 976-982 ◽  
Author(s):  
Nenad Ignjatović ◽  
Petar Ninkov ◽  
Vesna Kojić ◽  
Miloš Bokurov ◽  
Vladimir Srdić ◽  
...  

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