Description and characterization of a novel live-attenuated tri-segmented Machupo virus in Guinea pigs

The tuberculin activity of protoplasmic extracts isolated from living BCG was purified successively by gel filtration on Sephadex G-100 and G-75, and by electrophoresis on 7.5% and on gradient (6–18%) polyacrylamide gels. The tuberculin-active fractions, as determined in BCG-sensitized guinea pigs, were used as the starting material for each of the following fractionation steps.The physicochemical properties and the antigenic activity of the biologically active fractions have shown that a single component, or only a few ones with similar properties, possessed high tuberculin activity. These active components were proteins having relatively high molecular weights (about 72 000) and could behave as antigens.

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In Vivo Neurochemical Characterization of Developing Guinea Pigs and the Effect of Chronic Fetal Hypoxia

Neurochemical Research ◽

10.1007/s11064-016-1924-y ◽

2016 ◽

Vol 41 (7) ◽

pp. 1831-1843 ◽

Cited By ~ 5

Author(s):

Wen-Tung Wang ◽

Phil Lee ◽

Yafeng Dong ◽

Hung-Wen Yeh ◽

Jieun Kim ◽

...

Keyword(s):

Guinea Pigs ◽

Fetal Hypoxia

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Isolation and Characterization of a Shigella flexneri Invasin Complex Subunit Vaccine

Infection and Immunity ◽

10.1128/iai.68.12.6624-6632.2000 ◽

2000 ◽

Vol 68 (12) ◽

pp. 6624-6632 ◽

Cited By ~ 54

Author(s):

K. Ross Turbyfill ◽

Antoinette B. Hartman ◽

Edwin V. Oaks

Keyword(s):

Guinea Pigs ◽

Shigella Flexneri ◽

Exchange Chromatography ◽

Lung Model ◽

Macromolecular Complex ◽

Specific Response ◽

Virulence Proteins ◽

Isolation And Characterization ◽

Iga Antibody

ABSTRACT The invasiveness and virulence of Shigella spp. are largely due to the expression of plasmid-encoded virulence factors, among which are the invasion plasmid antigens (Ipa proteins). After infection, the host immune response is directed primarily against lipopolysaccharide (LPS) and the virulence proteins (IpaB, IpaC, and IpaD). Recent observations have indicated that the Ipa proteins (IpaB, IpaC, and possibly IpaD) form a multiprotein complex capable of inducing the phagocytic event which internalizes the bacterium. We have isolated a complex of invasins and LPS from water-extractable antigens of virulent shigellae by ion-exchange chromatography. Western blot analysis of the complex indicates that all of the major virulence antigens of Shigella, including IpaB, IpaC, and IpaD, and LPS are components of this macromolecular complex. Mice or guinea pigs immunized intranasally with purified invasin complex (invaplex), without any additional adjuvant, mounted a significant immunoglobulin G (IgG) and IgA antibody response against theShigella virulence antigens and LPS. The virulence-specific response was very similar to that previously noted in primates infected with shigellae. Guinea pigs (keratoconjunctivitis model) or mice (lethal lung model) immunized intranasally on days 0, 14, and 28 and challenged 3 weeks later with virulent shigellae were protected from disease (P < 0.01 for both animal models).

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Pharmacological characterization of TA-2005, a newly developed bronchodilating agent. I. Tracheal relaxing effects and β2-selectivity in guinea pigs.

The Japanese Journal of Pharmacology ◽

10.1016/s0021-5198(19)38255-1 ◽

1991 ◽

Vol 55 ◽

pp. 82

Author(s):

Hiideo Kikkawa ◽

Kazuaki Naito ◽

Katsuo Ikezawa

Keyword(s):

Guinea Pigs ◽

Pharmacological Characterization

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Characterization of the antigen-induced contraction of colonic smooth muscle from sensitized guinea pigs

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1992.262.1.g144 ◽

1992 ◽

Vol 262 (1) ◽

pp. G144-G149 ◽

Cited By ~ 2

Author(s):

M. S. Barnette ◽

M. Grous

Keyword(s):

Smooth Muscle ◽

Inflammatory Mediators ◽

Guinea Pigs ◽

Colonic Motility ◽

Initial Response ◽

Late Response ◽

Circular Smooth Muscle ◽

Neuronal Interactions ◽

Leukotriene Antagonist

To study the potential of inflammatory mediators to alter colonic motility, we characterized the response of distal colonic smooth muscle to antigen challenge. Addition of ovalbumin to isolated segments of circular smooth muscle obtained from sensitized guinea pigs produced a biphasic contraction. The initial response consisted of a rapid contraction followed by a late response, which was a more sustained but smaller increase in tone and phasic activity. Interestingly, these two responses could be antagonized differentially. Pretreatment with mepyramine (10 microM) inhibited the initial response, whereas the leukotriene antagonist WY 48252 (10 microM) inhibited the late response. The mast cell stabilizer doxantrazole (0.1 microM) reduced only the late response. Inhibition of cyclooxygenase with meclofenamic acid (1 microM) potentiated both responses, whereas blocking neuronal activity with tetrodotoxin (1 microM) only enhanced the initial response. These data indicate clear differences between the inflammatory mediators important in the initial vs. the late response. The initial response is probably mediated by the release of histamine, with enteric neuronal interactions important in attenuating the magnitude of this response. In contrast, the late response appears to be mediated by the release of peptidyl leukotrienes. In this system, cyclooxygenase products apparently function to decrease the response of the smooth muscle to these mediators. These results suggest that release of mediators during an inflammatory response could profoundly alter colonic motility and that these alterations may be important in the pathophysiological manifestations associated with colonic inflammation.(ABSTRACT TRUNCATED AT 250 WORDS)

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