Macular sensitivity in patients with congenital stationary night-blindness

AimTo evaluate and correlate mean light sensitivity thresholds (MLST) in patients with congenital stationary night-blindness (CSNB) in comparison with healthy subjects using microperimetry (MP1).MethodsEleven patients with CSNB and 13 healthy subjects were compared. In all subjects, static threshold perimetry was performed using MP1 evaluating the central 6 mm of the retina. This central retinal area was divided into three rings through using the ETDRS grid algorithm with an innermost (1 mm), inner (3 mm) and outer ring (6 mm). The MLSTs were acquired in nine sectors of the ETDRS grid. A comparison of MLST was performed between both groups using a t-test (significance level p<0.005).ResultsA significant reduction of MLST in the fovea (innermost ring, 1 mm) was observed for patients with CSNB (7.2±3.90 dB) in comparison to healthy subjects (19.7±0.75; p<0.0001). Similarly, comparison of MLST in all other sectors (superior/inferior/temporal and nasal) within the inner and outer ring revealed a statistically significant reduction in patients with CSNB compared with healthy subjects (p<0.001).ConclusionsExamination of macular retinal sensitivity intensity using MP1 revealed for the first time a significant reduction of MLST within the central 6 mm of the retina in patients with CSNB compared with healthy subjects. This finding supports MP1 as an additional diagnostic tool when examining patients with retinal dysfunctions such as CSNB.

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Faculty Opinions recommendation of Congenital stationary night blindness type 2 mutations S229P, G369D, L1068P, and W1440X alter channel gating or functional expression of Ca(v)1.4 L-type Ca2+ channels.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1024014.285837 ◽

2005 ◽

Author(s):

Gerald Zamponi

Keyword(s):

Night Blindness ◽

Channel Gating ◽

Functional Expression ◽

Congenital Stationary Night Blindness ◽

Ca2 Channels

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Detection and Quantification of 7-Hydroxydehydroepiandrosterone Epimers in Three Body Fluids

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20020010 ◽

2002 ◽

Vol 67 (1) ◽

pp. 10-18 ◽

Cited By ~ 1

Author(s):

Richard Hampl ◽

Martin Hill ◽

Luboslav Stárka

Keyword(s):

Healthy Subjects ◽

Serum Levels ◽

Body Fluids ◽

Gas Chromatography Mass Spectrometry ◽

Specific Radioimmunoassay ◽

Order Of Magnitude ◽

Three Body ◽

First Time ◽

Nanomolar Range ◽

Detection And Quantification

3β,7α-Dihydroxyandrost-5-en-17-one (1) (7α-OH-DHEA) and its 7β-hydroxy epimer 2 (7β-OH-DHEA) - 7α- and 7β-hydroxydehydroepiandrosterone - were detected and quantified in three human body fluids: in blood serum, saliva and ejaculate. Specific radioimmunoassay and gas chromatography-mass spectrometry have been used. For the first time the data on changes of these dehydroepiandrosterone metabolites are reported for a representative group of healthy subjects of both sexes (172 females and 217 males) during the life span. The serum levels of both 7-hydroxydehydroepiandrosterone epimers in serum and also in semen were in the low nanomolar range, while concentrations by one order of magnitude lower were found in saliva, but still within the detection limit. The results will serve as a basis for comparative studies of 7-hydroxydehydroepiandrosterone levels under various pathophysiological conditions, with a particular respect to autoimmune disorders.

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Methylphenidate reduces orienting bias in healthy individuals

Journal of Psychopharmacology ◽

10.1177/0269881121996884 ◽

2021 ◽

pp. 026988112199688

Author(s):

Leehe Peled-Avron ◽

Hagar Gelbard Goren ◽

Noa Brande-Eilat ◽

Shirel Dorman-Ilan ◽

Aviv Segev ◽

...

Keyword(s):

Healthy Subjects ◽

Asymmetric Effect ◽

Healthy Individuals ◽

Double Blind ◽

Spatial Orienting ◽

Individual Trait ◽

Neurological Patients ◽

Dopamine Signaling ◽

First Time ◽

Neural Effect

Background: Healthy individuals show subtle orienting bias, a phenomenon known as pseudoneglect, reflected in a tendency to direct greater attention toward one hemispace. Accumulating evidence indicates that this bias is an individual trait, and attention is preferentially directed contralaterally to the hemisphere with higher dopamine signaling. Administration of methylphenidate (MPH), a dopamine transporter inhibitor, was shown to normalize aberrant spatial attention bias in psychiatric and neurological patients, suggesting that the reduced orienting bias following administration of MPH reflects an asymmetric effect of the drug, increasing extracellular dopamine in the hemisphere with lower dopamine signaling. Aim: We predicted that, similarly to its effect on patients with brain pathology, MPH will reduce the orienting bias in healthy subjects. Methods: To test this hypothesis, we examined the behavioral effects of a single dose (20 mg) of MPH on orienting bias in 36 healthy subjects (18 females) in a randomized, double-blind placebo-controlled, within-subject design, using the greyscales task, which has been shown to detect subtle attentional biases in both patients and healthy individuals. Results/outcomes: Results demonstrate that healthy individuals vary in both direction and magnitude of spatial orienting bias and show reduced magnitude of orienting bias following MPH administration, regardless of the initial direction of asymmetry. Conclusions/interpretations: Our findings reveal, for the first time in healthy subjects, that MPH decreases spatial orienting bias in an asymmetric manner. Given the well-documented association between orienting bias and asymmetric dopamine signaling, these findings also suggest that MPH might exert a possible asymmetric neural effect in the healthy brain.

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