Paradoxical effect of spatially homogenous transparent fields on simultaneous contrast illusions

2014 ◽  
Vol 31 (4) ◽  
pp. A307 ◽  
Author(s):  
Erica Dixon ◽  
Arthur G. Shapiro
Keyword(s):  
Simultaneous Contrast ◽  
Paradoxical Effect ◽  
Contrast Illusions

Paradoxical effect of oral lorazepam in a premedication for ERCP

2005 ◽  
Vol 43 (05) ◽  
Author(s):  
G Weitz ◽  
P Wellhöner ◽  
A Sauer ◽  
A Brüning ◽  
N Homann ◽  
...  
Keyword(s):  
Paradoxical Effect

Physical Distancing and Future COVID-19 Deaths in Brazil: Evidence of a Paradoxical Effect

2020 ◽  
Author(s):  
Bruno Campello de Souza ◽  
Fernando Menezes Campello de Souza
Keyword(s):  
Paradoxical Effect

scholarly journals The Paradoxical Effect Hypothesis of Abused Drugs in a Rat Model of Chronic Morphine Administration

2021 ◽  
Vol 10 (15) ◽  
pp. 3197
Author(s):  
Yinghao Yu ◽  
Alan Bohan He ◽  
Michelle Liou ◽  
Chenyin Ou ◽  
Anna Kozłowska ◽  
...  
Keyword(s):  
Drug Addiction ◽  
Basolateral Amygdala ◽  
Neural Substrates ◽  
Plasma Corticosterone ◽  
High Plasma ◽  
Paradoxical Effect ◽  
Chronic Morphine ◽  
Morphine Administration ◽  
Abused Drugs ◽  
Effect Hypothesis

A growing body of studies has recently shown that abused drugs could simultaneously induce the paradoxical effect in reward and aversion to influence drug addiction. However, whether morphine induces reward and aversion, and which neural substrates are involved in morphine’s reward and aversion remains unclear. The present study first examined which doses of morphine can simultaneously produce reward in conditioned place preference (CPP) and aversion in conditioned taste aversion (CTA) in rats. Furthermore, the aversive dose of morphine was determined. Moreover, using the aversive dose of 10 mg/kg morphine tested plasma corticosterone (CORT) levels and examined which neural substrates were involved in the aversive morphine-induced CTA on conditioning, extinction, and reinstatement. Further, we analyzed c-Fos and p-ERK expression to demonstrate the paradoxical effect—reward and aversion and nonhomeostasis or disturbance by morphine-induced CTA. The results showed that a dose of more than 20 mg/kg morphine simultaneously induced reward in CPP and aversion in CTA. A dose of 10 mg/kg morphine only induced the aversive CTA, and it produced higher plasma CORT levels in conditioning and reacquisition but not extinction. High plasma CORT secretions by 10 mg/kg morphine-induced CTA most likely resulted from stress-related aversion but were not a rewarding property of morphine. For assessments of c-Fos and p-ERK expression, the cingulate cortex 1 (Cg1), prelimbic cortex (PrL), infralimbic cortex (IL), basolateral amygdala (BLA), nucleus accumbens (NAc), and dentate gyrus (DG) were involved in the morphine-induced CTA, and resulted from the aversive effect of morphine on conditioning and reinstatement. The c-Fos data showed fewer neural substrates (e.g., PrL, IL, and LH) on extinction to be hyperactive. In the context of previous drug addiction data, the evidence suggests that morphine injections may induce hyperactivity in many neural substrates, which mediate reward and/or aversion due to disturbance and nonhomeostasis in the brain. The results support the paradoxical effect hypothesis of abused drugs. Insight from the findings could be used in the clinical treatment of drug addiction.

Immunochemical Studies on Antithrombin III

1979 ◽  
Author(s):  
E.J. McKay
Keyword(s):  
Antithrombin Iii ◽  
The Other ◽  
Antigenic Determinants ◽  
Immunochemical Analysis ◽  
Paradoxical Effect ◽  
Test Protocol ◽  
Agar Gel ◽  
High Affinity ◽  
Time Required ◽  
Antigen Antibody

Depressed Antithrombin III (AT) levels Increase thrombic tendency in man, therefore value in assaying this protein has been established. Immunochemical analysis of AT in clinical disease has however proved controversial, consequently systematic studies were undertaken to rationalize the requirements necessary to optimise these methods in particular electro-Immunoassay. The known binding affinity of AT for heparin has been exploited to differentiate high affinity AT from its inhibitor - protease complexes and has resulted in reports stating that heparin added to the agar gel prior to electrophoresis significantly reduces the time required for completion of antigen/antibody complexes. Our studies however have demonstrated that the antibody required for quantitative analysis must be capable of not only reacting with “native” antigenic determinants of AT but also with “neo” antigens that are exposed when inhibitor-protease complexes are formed. Heparin should not be used in the test protocol, for it has a paradoxical effect on Immunopreclpltation in gels, masking some antigenic determinants of unbound - high affinity AT on one hand, and appear to disrupt the Immunoprecipitin “rocket” formed with the inhibitor-protease complexes during electrophoresis on the other.

Paradoxical effect of trifluoperazine, a calmodulin antagonist, on pepsinogen secretion

1986 ◽  
Vol 40 (6) ◽  
pp. 624-631 ◽  
Author(s):  
I.M. Modlin ◽  
G.R. Fratesi ◽  
D.E. Schafer ◽  
M.J. Zdon ◽  
G.H. Ballantyne ◽  
...  
Keyword(s):  
Paradoxical Effect ◽  
Calmodulin Antagonist ◽  
Pepsinogen Secretion

scholarly journals Paradoxical Effect of Caspofungin: Reduced Activity against Candida albicans at High Drug Concentrations

2004 ◽  
Vol 48 (9) ◽  
pp. 3407-3411 ◽  
Author(s):  
David A. Stevens ◽  
Marife Espiritu ◽  
Rachana Parmar
Keyword(s):  
Candida Albicans ◽  
Resistance Mechanisms ◽  
Paradoxical Effect ◽  
Fungal Cell ◽  
High Drug ◽  
Minimum Fungicidal Concentration ◽  
Drug Concentrations ◽  
High Concentrations ◽  
Glucan Synthesis

ABSTRACT Resistance problems with caspofungin, an echinocandin inhibitor of fungal cell wall glucan synthesis, have been rare. We noted paradoxical turbid growth of Candida albicans isolates in broth in some high (supra-MIC) concentrations. Among isolates submitted for susceptibility testing and screened at drug concentrations up to 12.5 μg/ml, the frequency was 16%. Analysis of the turbid growth indicated slowing of growth in the presence of drug but with numbers of CFU up to 72% those of drug-free controls. Clearing of growth again by the highest drug concentrations produced a quadriphasic pattern in a tube dilution series. Cells growing at high drug concentrations were not resistant on retesting but showed the paradoxical effect of the parent. Among a selected series of isolates tested at concentrations up to 50 μg/ml, an additional 53% showed a “mini-paradoxical effect”: no turbid growth but incomplete killing at high concentrations (supra-minimum fungicidal concentration). These effects were reproducible; medium dependent in extent; noted in macro- and microdilution, in the presence or absence of serum, and on agar containing drug (but not when drug concentrations were not constant, as in agar diffusion); not seen with other echinocandins and less commonly in other Candida species; and not due to destruction of drug in tubes showing the effect. Cooperative enhancement of inhibition by a second drug could eradicate the effect. We postulate that high drug concentrations derepress or activate resistance mechanisms. The abilities of subpopulations to survive at high drug concentrations could have in vivo consequences.

scholarly journals Species Identification and Antifungal Susceptibility Patterns of Species Belonging to Aspergillus Section Nigri

2009 ◽  
Vol 53 (10) ◽  
pp. 4514-4517 ◽  
Author(s):  
Laura Alcazar-Fuoli ◽  
Emilia Mellado ◽  
Ana Alastruey-Izquierdo ◽  
Manuel Cuenca-Estrella ◽  
Juan L. Rodriguez-Tudela
Keyword(s):  
Phylogenetic Analysis ◽  
Species Identification ◽  
Antifungal Susceptibility ◽  
Morphological Features ◽  
Correct Classification ◽  
Paradoxical Effect ◽  
Aspergillus Section Nigri ◽  
Susceptibility Patterns ◽  
Aspergillus Section

ABSTRACT A phylogenetic analysis was performed for 34 Aspergillus strains belonging to section Nigri. Molecular methods allowed for the correct classification into three different clades (A. niger, A. tubingensis, and A. foetidus). Correlation with in vitro itraconazole susceptibility distinguished the following three profiles: susceptible, resistant, and showing a paradoxical effect. A number of different species whose morphological features resemble those of A. niger showed unusual MICs to itraconazole that have never been described for the Aspergillus genus.

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