scholarly journals Indomethacin reproducibly induces metamorphosis in Cassiopea xamachana scyphistomae

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e2979 ◽  
Author(s):  
Patricia Cabrales-Arellano ◽  
Tania Islas-Flores ◽  
Patricia E. Thomé ◽  
Marco A. Villanueva
Keyword(s):  
Model System ◽  
Optimal Conditions ◽  
Molecular Analyses ◽  
Lugol’S Iodine ◽  
Biological Phenomena ◽  
Cassiopea Xamachana ◽  
Asexual Cycle ◽  
Planula Larvae ◽  
Induction Of Metamorphosis ◽  
Metamorphosis Induction

Cassiopea xamachana jellyfish are an attractive model system to study metamorphosis and/or cnidarian–dinoflagellate symbiosis due to the ease of cultivation of their planula larvae and scyphistomae through their asexual cycle, in which the latter can bud new larvae and continue the cycle without differentiation into ephyrae. Then, a subsequent induction of metamorphosis and full differentiation into ephyrae is believed to occur when the symbionts are acquired by the scyphistomae. Although strobilation induction and differentiation into ephyrae can be accomplished in various ways, a controlled, reproducible metamorphosis induction has not been reported. Such controlled metamorphosis induction is necessary for an ensured synchronicity and reproducibility of biological, biochemical, and molecular analyses. For this purpose, we tested if differentiation could be pharmacologically stimulated as in Aurelia aurita, by the metamorphic inducers thyroxine, KI, NaI, Lugol’s iodine, H2O2, indomethacin, or retinol. We found reproducibly induced strobilation by 50 μM indomethacin after six days of exposure, and 10–25 μM after 7 days. Strobilation under optimal conditions reached 80–100% with subsequent ephyrae release after exposure. Thyroxine yielded inconsistent results as it caused strobilation occasionally, while all other chemicals had no effect. Thus, indomethacin can be used as a convenient tool for assessment of biological phenomena through a controlled metamorphic process in C. xamachana scyphistomae.

scholarly journals Indomethacin reproducibly induces metamorphosis in Cassiopea xamachana scyphistomae

2016 ◽  
Author(s):  
Patricia Cabrales-Arellano ◽  
Tania Islas-Flores ◽  
Patricia E. Thomé ◽  
Marco A. Villanueva
Keyword(s):  
Model System ◽  
Optimal Conditions ◽  
Molecular Analyses ◽  
Lugol’S Iodine ◽  
Biological Phenomena ◽  
Cassiopea Xamachana ◽  
Asexual Cycle ◽  
Planula Larvae ◽  
Induction Of Metamorphosis ◽  
Metamorphosis Induction

Cassiopea xamachana jellyfish are an attractive model system to study metamorphosis and/or cnidarian-dinoflagellate symbiosis due to the ease of cultivation of their planula larvae and scyphistomae through their asexual cycle, in which the latter can bud new larvae and continue the cycle without differentiation into ephyrae. Then, a subsequent induction of metamorphosis and full differentiation into ephyrae is believed to occur when the symbionts are acquired by the scyphistomae. Although strobilation induction and differentiation into ephyrae can be accomplished in various ways, a controlled, reproducible metamorphosis induction has not been reported. Such controlled metamorphosis induction is necessary for an ensured synchronicity and reproducibility of biological, biochemical and molecular analyses. For this purpose, we tested if differentiation could be pharmacologically stimulated as in Aurelia aurita, by the metamorphic inducers thyroxine, KI, NaI, lugol's iodine, H2O2, indomethacin, or retinol. We found reproducibly induced strobilation by 50 µM indomethacin after 6 days of exposure, and 10-25 µM after 7 days. Strobilation under optimal conditions reached 80-100% with subsequent ephyrae release after exposure. Thyroxine yielded inconsistent results as it caused strobilation occasionally, while all other chemicals had no effect. Thus, indomethacin can be used as a convenient tool for assessment of biological phenomena through a controlled metamorphic process in C. xamachana scyphistomae.

scholarly journals Indomethacin reproducibly induces metamorphosis in Cassiopea xamachana scyphistomae

2016 ◽  
Author(s):  
Patricia Cabrales-Arellano ◽  
Tania Islas-Flores ◽  
Patricia E. Thomé ◽  
Marco A. Villanueva
Keyword(s):  
Model System ◽  
Optimal Conditions ◽  
Molecular Analyses ◽  
Lugol’S Iodine ◽  
Biological Phenomena ◽  
Cassiopea Xamachana ◽  
Asexual Cycle ◽  
Planula Larvae ◽  
Induction Of Metamorphosis ◽  
Metamorphosis Induction

Cassiopea xamachana jellyfish are an attractive model system to study metamorphosis and/or cnidarian-dinoflagellate symbiosis due to the ease of cultivation of their planula larvae and scyphistomae through their asexual cycle, in which the latter can bud new larvae and continue the cycle without differentiation into ephyrae. Then, a subsequent induction of metamorphosis and full differentiation into ephyrae is believed to occur when the symbionts are acquired by the scyphistomae. Although strobilation induction and differentiation into ephyrae can be accomplished in various ways, a controlled, reproducible metamorphosis induction has not been reported. Such controlled metamorphosis induction is necessary for an ensured synchronicity and reproducibility of biological, biochemical and molecular analyses. For this purpose, we tested if differentiation could be pharmacologically stimulated as in Aurelia aurita, by the metamorphic inducers thyroxine, KI, NaI, lugol's iodine, H2O2, indomethacin, or retinol. We found reproducibly induced strobilation by 50 µM indomethacin after 6 days of exposure, and 10-25 µM after 7 days. Strobilation under optimal conditions reached 80-100% with subsequent ephyrae release after exposure. Thyroxine yielded inconsistent results as it caused strobilation occasionally, while all other chemicals had no effect. Thus, indomethacin can be used as a convenient tool for assessment of biological phenomena through a controlled metamorphic process in C. xamachana scyphistomae.

scholarly journals Resistance of Listeria monocytogenes biofilms to disinfectants 326

2010 ◽  
Vol 28 (No. 4) ◽  
pp. 326-332 ◽  
Author(s):  
S. Purkrtová ◽  
H. Turoňová ◽  
T. Pilchová ◽  
K. Demnerová ◽  
J. Pazlarová
Keyword(s):  
Listeria Monocytogenes ◽  
Reference Strain ◽  
Model Organism ◽  
Model System ◽  
Optimal Conditions ◽  
Microtiter Plates ◽  
Peptone Water ◽  
Optimal Values ◽  
Biofilm Development ◽  
Chloride Treatment

We studied the optimal conditions for the biofilm development by Listeria monocytogenes on a model system represented by microtiter plates, and also for determined some effective disinfectant agents. Listeria monocytogenes ATCC 13932 and an industrial isolate of Listeria monocytogenes Lm-24 were compared as to their abilities to form biofilms. The starting concentration of the cells leading to the most reproducible results was 0.5 McFarland. The temperatures tested ranged between 8°C to 37°C, the optimal values to form biofilm in buffered peptone water (BPW) with 0.05% glucose were 25°C and 30°C. Under comparable conditions the persistent strain L. monocytogenes Lm-24 constituted more massive biofilm than did the reference strain. The following disinfectants were applied: Savo, Merades Alco, benzalalkonium chloride. A persistent industry in isolate Listeria monocytogenes Lm-24 was used as the model organism for these tests. Benzalalkonium chloride treatment was found to be the most efficient way to damage the biofilm. One minute treatment with 500 mg/l was lethal for the biofilm cells, and that with 125 mg/l for planctonic cells. Savo suppresed the viability of the biofilm cells only by about 20% on average while being lethal for planctonic cells. Merades Alco exhibited only a weak effect on both the biofilm and planctonic cells.

scholarly journals Fundamental aspects of the interaction of propidium diiodide with nuclei acids studied in a model system of polyacrylamide films.

1981 ◽  
Vol 29 (8) ◽  
pp. 929-936 ◽  
Author(s):  
J Tas ◽  
G Westerneng
Keyword(s):  
Staining Method ◽  
Model System ◽  
Appreciable Amount ◽  
Optimal Conditions ◽  
Binding Ability ◽  
Qualitative And Quantitative ◽  
Dna And Rna ◽  
Linear Relationships ◽  
The Stability ◽  
Very High

Qualitative and quantitative aspects of the fluorescent propidium diiodide (PI) staining method have been investigated with model films of polyacrylamide gel incorporated with DNA, RNA, and other macromolecular compounds. PI was found to bind specifically to DNA and RNA, most probably by intercalation into double-stranded regions. Proteins, glycogen, and glycosaminoglycans did not show fluorescence after PI staining. Optimal conditions for dye binding and differentiation have been defined. The stability of nucleic acid-PI complexes, as present in model films, was shown to be very high in distilled water, while dissociation rapidly occurred in ionic media. Linear relationships were found between the fluorescence intensity of bound PI and both the thickness of the model films and the amount of DNA or RNA incorporated. The presence of histone protein bound ionically to DNA did not influence the fluorescent PI binding ability in any appreciable amount.

The Effects of the UV-Blocker Oxybenzone (Benzophenone-3) on Planulae Swimming and Metamorphosis of the Scyphozoans Cassiopea xamachana and Cassiopea frondosa

Oceans ◽  
2020 ◽  
Vol 1 (4) ◽  
pp. 174-180
Author(s):  
William K. Fitt ◽  
Dietrich K. Hofmann
Keyword(s):  
Cassiopea Xamachana ◽  
Symbiotic Dinoflagellates ◽  
Detrimental Impact ◽  
Complete Metamorphosis ◽  
Planula Larvae

Benzophenones are UV-blockers found in most common sunscreens. The ability of Scyphozoan planula larvae of Cassiopea xamachana and C. frondosa to swim and complete metamorphosis in concentrations 0–228 µg/L benzophenone-3 (oxybenzone) was tested. Planulae of both species swam in erratic patterns, 25–30% slower, and experienced significant death (p < 0.05) in the highest concentrations of oxybenzone tested, whereas the larvae exhibited normal swimming patterns and no death in ≤2.28 µg/L oxybenzone. In addition, metamorphosis decreased 10–30% over 3 days for both species maintained in 228 µg/L oxybenzone. These effects do not involve symbiotic dinoflagellates, as planulae larvae of Cassiopea sp. are aposymbiotic. It is concluded that oxybenzone can have a detrimental impact on these jellyfish.

scholarly journals Antioxidant activity and sensory analysis of murtilla (Ugni molinae Turcz.) fruit extracts in an oil model system

2017 ◽  
Vol 68 (1) ◽  
pp. 183
Author(s):  
T. R. Augusto-Obara ◽  
F. Pirce ◽  
E. Scheuermann ◽  
M. H.F. Spoto ◽  
T. M.F.S. Vieira
Keyword(s):  
Antioxidant Activity ◽  
Dry Matter ◽  
Phenolic Content ◽  
Model System ◽  
Total Phenolic ◽  
Optimal Conditions ◽  
Oven Test ◽  
Fruit Extracts ◽  
Peroxide Values ◽  
Ugni Molinae

An oil model system was used to analyze the antioxidant activity of Chilean fruit extracts and to determine their odor sensory effect. Hydroalcoholic extracts from wild and 14-4 genotype murtilla (Ugni molinae Turcz.) fruit were assessed by the Response Surface Methodology. The optimal conditions for producing high total phenolic-content extracts were 49.5% (v/v) ethanol at 30 ºC, which yielded 18.39 and 26.14 mg GAE·g-1 dry matter, respectively. The optimized extracts were added to a lipid model system and evaluated via the Schaal Oven Test. After 96 hours, 150 and 200 mg·kg-1 oil of the wild and 14-4 genotype extracts, respectively, showed an antioxidant capacity similar to TBHQ (200 mg·kg-1 oil) in terms of peroxide values and odor. Thus, murtilla fruit extracts are a natural source of antioxidants for protecting lipidic foods, such as soybean oil.

Locomotive Characteristics of Body and Limb in a Terrestrial Vertebrates

2012 ◽  
Vol 249-250 ◽  
pp. 180-188 ◽  
Author(s):  
Sung Ho Park ◽  
Dong Pyo Hong
Keyword(s):  
Minimum Energy ◽  
Walking Robots ◽  
Optimal Conditions ◽  
Body System ◽  
Walking Machine ◽  
Terrestrial Vertebrates ◽  
Biological Phenomena ◽  
Machine Covering ◽  
Biological Concepts ◽  
Multi Body

Locomotion of many living creatures remains infinitely more advanced and elegant than that of present-day legged walking robots. However, the principles of existing systems are based more on technical rather than on biological concepts, yielding unstable locomotion with low speed. In order to apply those advanced biological phenomena to the design of a Quadruped, the structural and locomotive characteristics of several selected animals are studied. Also, the four-legged walking machine, covering all existing leg arrangements and locomotion patterns, is modeled by a rigid multi-body system, consisting of 13 links and 12 joints. As a time variable, the model is simulated to prove the optimal conditions, which satisfy the principle of minimum energy expenditure.

scholarly journals Taxonomic revision of grass frogs (Ptychadenidae, Ptychadena) endemic to the Ethiopian highlands

ZooKeys ◽  
2021 ◽  
Vol 1016 ◽  
pp. 77-141
Author(s):  
Sandra Goutte ◽  
Jacobo Reyes-Velasco ◽  
Xenia Freilich ◽  
Abeje Kassie ◽  
Stephane Boissinot
Keyword(s):  
Species Complex ◽  
Taxonomic Revision ◽  
Model System ◽  
Type Specimens ◽  
Molecular Analyses ◽  
Ethiopian Highlands ◽  
Distribution Maps ◽  
Acoustic Identification ◽  
High Elevations ◽  
Lines Of Evidence

Frogs of the genus Ptychadena that inhabit the Ethiopian highlands serve as a model system to understand biogeography, diversification, and adaptations to high elevations. Despite recent studies focusing on the systematics of this group, the taxonomy of the Ptychadena neumanni species complex remains only partially resolved, owing largely to the morphological resemblance of its members. Here, the taxonomy of this historically problematic group of frogs is revised by integrating morphological and molecular analyses on both century-old type specimens and more recently collected material. Based on these multiple lines of evidence, the P. neumanni species complex is shown to be more speciose than previously thought and four new species are described. With the aim of clarifying and stabilizing the taxonomy of the group, six species are also re-described and morphological and acoustic identification keys are provided. This study also establishes species distribution maps and reveals important differences in range size between the members of the P. neumanni complex, calling for adapted conservation measures across the Ethiopian highlands.

scholarly journals Salting-out extraction of catechol and hydroquinone from aqueous solutions and urine samples

2003 ◽  
Vol 2 (5) ◽  
pp. 293-299 ◽  
Author(s):  
Goran Nikolic ◽  
Jelica Perovic ◽  
Ruzica Nikolic ◽  
Milorad Cakic
Keyword(s):  
Aqueous Solutions ◽  
Extraction Efficiency ◽  
Model System ◽  
Diisopropyl Ether ◽  
Urine Samples ◽  
Optimal Conditions ◽  
Salting Out ◽  
Sodium Potassium ◽  
Real Samples ◽  
Magnesium Salts

The influence of ammonium, sodium, potassium, and magnesium chlorides and sulfates on the extraction of catechol and hydroquinone with diethyl and diisopropyl ether was studied. All the salts investigated in this study largely increased the extraction efficiency of both catechol and hydroquinone from aqueous solutions, magnesium salts being the most efficient salting-out agents. The extraction efficiency in the presence of magnesium salts in comparison to the extraction efficiencies from the salt-free aqueous solutions increased from 14%, in the case of catechol extraction with diethyl ether, up to about 90%, in the case of hydroquinone extraction with diisopropyl ether. The extraction from spiked urine samples proved that investigation of salting-out effect in aqueous solutions could be used as a good model system for the reliable choice of optimal conditions for catechol and hydroquinone extraction from real samples.

scholarly journals Use of 1-Methylcyclopropene in Ornamentals: Carnations as a Model System for Understanding Mode of Action

HortScience ◽  
2008 ◽  
Vol 43 (1) ◽  
pp. 95-98 ◽  
Author(s):  
Michael S. Reid ◽  
Fisun G. Çelikel
Keyword(s):  
Competitive Inhibition ◽  
Dianthus Caryophyllus ◽  
Model System ◽  
Optimal Conditions ◽  
Cut Flowers ◽  
Potted Plants ◽  
Commercial Use ◽  
Treatment Conditions ◽  
Inhibition Response ◽  
A Site

The first commercial use of 1-methylcyclopropene (1-MCP) was with cut flowers and potted plants, and treatment with this compound is still the preferred strategy for protection of most ethylene-sensitive crops. Research is continuing into optimum treatment conditions and strategies for efficient application in commerce. In studies using carnation (Dianthus caryophyllus L. ‘White Sim’) petals to determine the optimal conditions for commercial treatment, we noted some aspects of the inhibition response that were not consistent with the current competitive inhibition model of 1-MCP action. Our data are better explained by an alternative model in which 1-MCP binds to a site that is exposed during the allosteric changes that accompany the enzymatic activities of the binding site in the absence of ethylene.

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