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S Breiter

Publications and source records attributed to S Breiter.

2 recordsLinked to original sources

Classic and non-classic progesterone receptors are both expressed in human spermatozoa.

Progesterone is one of the physiological inducers of the acrosome reaction in mammalian spermatozoa. The receptor that responds to progesterone is not yet identified, and its properties differ in many aspects from the properties of the classic nuclear progesterone receptor, suggesting the participation of a novel or non-classic receptor. In this study, we investigated the expression of a novel progesterone-binding protein (hmPR1/PGMRC1) and its ortholog (hmPR2/PGMRC2), which have previously been identified in liver microsomes and are considered receptor candidates, along with the nuclear progesterone receptor. The purification procedure was optimized with special emphasis on the control of leukocyte contamination in single donor samples. The results indicate that all three proteins are expressed in human sperm, as transcripts have been detected in 46 %, 42 % and 37.5 % of individual samples, respectively (n = 24).

Cell Separation↗

Mesial temporal spikes interfere with working memory.

The hippocampus and other mesial temporal structures support long-term memory and also are common foci for epilepsy. Recently it was shown that these brain structures may subserve the short-term storage and rehearsal processes called working memory in humans. We determined the accuracy of verbal and visuospatial working memory in the presence and in the absence of mesial temporal spikes in eight patients who had bilateral depth electrodes implanted to evaluate intractable epilepsy. Six of eight patients had declines in working memory performance during mesial temporal spiking, with the greatest disruption in spatial and verbal recall coincident with left hippocampal spikes (p = 0.019). Overall accuracy of working memory for all patients declined an average of 6% on spike trials. The two patients who did not have decreased accuracy during spike trials also had the best overall working memory performance. Mesial temporal spikes were not detected on extracranial recordings and yet may be associated with declines in working memory in some patients with epilepsy.

Action Potentials↗