Golden hamster (Mesocricetus auratus) as an experimental model forLeishmania(Viannia)braziliensisinfection

Parasitology ◽  
2013 ◽  
Vol 140 (6) ◽  
pp. 771-779 ◽  
Author(s):  
ADRIANO GOMES-SILVA ◽  
JOANNA GARDEL VALVERDE ◽  
RAQUEL PERALVA RIBEIRO-ROMÃO ◽  
ROSA MARIA PLÁCIDO-PEREIRA ◽  
ALDA MARIA DA-CRUZ
Keyword(s):  
Golden Hamster ◽  
Mesocricetus Auratus ◽  
Spleen Weight ◽  
Limiting Factor ◽  
Experimental Conditions ◽  
Adequate Model ◽  
Skin Ulcers ◽  
American Tegumentary Leishmaniasis ◽  
History Of ◽  
Experimental Protocols

SUMMARYThe lack of an adequate model forLeishmania(Viannia)braziliensisinfection is a limiting factor for studying American tegumentary leishmaniasis (ATL). The golden hamster (Mesocricetus auratus) is a promising model because besides being highly susceptible to dermotropicLeishmaniainfection, the lesions are very similar to cutaneous leishmaniasis (CL) in humans. However, differentLeishmaniaisolates or species and/or protocols have resulted in different outcomes, whereas no study has evaluated the reproducibility ofL. braziliensisinfection in this model. The natural history ofL. braziliensisinfection in 34 hamsters was evaluated by using a single parasite isolate in 8 independent experiments under similar experimental conditions. Clinical, histological and immunological analyses were performed. The hamsters presented skin ulcers similar to those observed in ATL. The intra-experiment lesion increment tended to show an intermediary variance. Histological analysis of infected skins showed granulomatous reaction, scarce amastigotes, and Schaumann's bodies. Blood lymphocytes proliferated in response to leishmanial antigens. The severity of the infection was positively correlated to spleen weight, and the titres of anti-LeishmaniaIgG antibodies. Our findings indicate that the hamster is an appropriate model for immunopathogenesis studies of CL caused byL. braziliensis, supporting its use in clinical, vaccine and chemotherapy experimental protocols.

scholarly journals Comparative investigation of lasing and amplification performance in cryogenic Yb:YLF systems

2021 ◽  
Vol 127 (3) ◽  
Author(s):  
Umit Demirbas ◽  
Martin Kellert ◽  
Jelto Thesinga ◽  
Yi Hua ◽  
Simon Reuter ◽  
...  
Keyword(s):  
Continuous Wave ◽  
Estimation Method ◽  
Laser Cavity ◽  
Comparative Investigation ◽  
Limiting Factor ◽  
Experimental Conditions ◽  
Temperature Estimation ◽  
Transverse Temperature ◽  
First Time

AbstractWe present detailed experimental results with cryogenic Yb:YLF gain media in rod-geometry. We have comparatively investigated continuous-wave (cw) lasing and regenerative amplification performance under different experimental conditions. In the cw lasing experiments effect of crystal doping, cw laser cavity geometry and pump wavelength on lasing performance were explored. Regenerative amplification behavior was analyzed and the role of depolarization losses on performance was investigated. A recently developed temperature estimation method was also employed for the first time in estimating average crystal temperature under lasing conditions. It is shown that the thermal lens induced by transverse temperature gradients is the main limiting factor and strategies for future improvements are discussed. To the best of our knowledge, the achieved results in this study (375 W in cw, and 90 W in regenerative amplification) are the highest average powers ever obtained from this system via employing the broadband E//a axis.

Biosorption of uranium(VI) from aqueous solution by biomass of brown algae Laminaria japonica

2014 ◽  
Vol 70 (1) ◽  
pp. 136-143 ◽  
Author(s):  
K. Y. Lee ◽  
K. W. Kim ◽  
Y. J. Baek ◽  
D. Y. Chung ◽  
E. H. Lee ◽  
...  
Keyword(s):  
Particle Size ◽  
Brown Algae ◽  
Activated Carbons ◽  
Laminaria Japonica ◽  
Limiting Factor ◽  
Stable Operation ◽  
Experimental Conditions ◽  
Wastewater Treatment Process ◽  
Radioactive Wastewater ◽  
Ionic Diffusivity

The uranium(VI) adsorption efficiency of non-living biomass of brown algae was evaluated in various adsorption experimental conditions. Several different sizes of biomass were prepared using pretreatment and surface-modification steps. The kinetics of uranium uptake were mainly dependent on the particle size of the prepared Laminaria japonica biosorbent. The optimal particle size, contact time, and injection amount for the stable operation of the wastewater treatment process were determined. Spectroscopic analyses showed that uranium was adsorbed in the porous inside structure of the biosorbent. The ionic diffusivity in the biomass was the dominant rate-limiting factor; therefore, the adsorption rate was significantly increased with decrease of particle size. From the results of comparative experiments using the biosorbents and other chemical adsorbents/precipitants, such as activated carbons, zeolites, and limes, it was demonstrated that the brown algae biosorbent could replace the conventional chemicals for uranium removal. As a post-treatment for the final solid waste reduction, the ignition treatment could significantly reduce the weight of waste biosorbents. In conclusion, the brown algae biosorbent is shown to be a favorable adsorbent for uranium(VI) removal from radioactive wastewater.

Gustatory Responses of the Hamster Mesocricetus auratus to Various Compounds Considered Sweet by Humans

1998 ◽  
Vol 80 (4) ◽  
pp. 2102-2112 ◽  
Author(s):  
Vicktoria Danilova ◽  
Göran Hellekant ◽  
Jean-Marie Tinti ◽  
Claude Nofre
Keyword(s):  
Cluster Analysis ◽  
Ethylene Glycol ◽  
Taste Aversion ◽  
Propionic Acid ◽  
Conditioned Taste Aversion ◽  
Golden Hamster ◽  
Mesocricetus Auratus ◽  
Chorda Tympani ◽  
Taste Sensation ◽  
Sodium Cyclamate

Danilova, Vicktoria, Göran Hellekant, Jean-Marie Tinti, and Claude Nofre. Gustatory responses of the hamster Mesocricetus auratus to various compounds considered sweet by humans. J. Neurophysiol. 80: 2102–2112, 1998. The taste of 30 compounds was studied in the golden hamster with three different methods: single-fiber recordings, two-bottle preference (TBP), and conditioned taste aversion (CTA) tests. On the whole, the results showed that the sense of taste in the hamster differs in many respects from that in humans because, of 26 tested compounds known as sweet to humans, 11 had no taste or tasted differently. The results also supported the notion that activity in S-fibers elicits liking and activity in Q- or H-fibers rejection. Specifically hierarchial cluster analysis of 36 single fibers from the chorda tympani proper nerve separated N-, H-, and S-clusters consisting of 11 sucrose-, 14 NaCl-, and 11 citric-best fibers. Ace-K, cyanosuosan, N-4-cyanophenyl- N′-cyanoguanidineacetate (CCGA), d-tryptophan, N-3,5-dichlorophenyl- N′-( S)-α-methylbenzylguanidineacetate (DMGA), saccharin, SC-45647, and suosan stimulated only the S-fibers, were significantly preferred in TBP tests, and generalized to sucrose in the CTA tests. Ethylene glycol stimulated the N-fibers in addition to the S-fibers. This explains its generalization to sucrose in CTA. Its toxicity may contribute to its rejection in TBP tests. Sodium cyclamate stimulated a few N- but no S-fibers, which may explain the nondiscriminatory TBP and CTA results. Glycine elicited its largest response in the S-fibers, although it also stimulated other fibers. The resulting mixed taste sensation may explain why it was not preferred in TBP, although it generalized to sucrose in the CTA. Alitame, aspartame, N-4-cyanophenylcarbamoyl-l-aspartyl-( R)-α-methylbenzylamine (CAM), N-4-cyanophenylcarbamoyl-( R, S)-3-amino-3-(3,4-methylenedioxyphenyl) propionic acid (CAMPA), N-( S)-2-methylhexanoyl-l-glutamyl-5-amino-2-pyridinecarbonitrile (MAGAP), N-1-naphthoyl-l-glutamyl-5-amino-2-pyridinecarbonitrile (NAGAP), NHDHC, superaspartame, and thaumatin were among the compounds considered sweet by humans that gave no response, were not discriminated in the TBP test, and gave no generalization in the CTA tests.

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