Stephan Jacob

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We tested the hypothesis that isolated steroids, claimed to act like pheromones, affect human psychological state or mood. In the first experiment, we established that two steroids, Delta4, 16-androstadien-3-one and 1,3,5(10)16-estratetraen-3-ol, modulated emotional states within 6 min of exposure. In men and women, neither steroid had specific effects on(More)
We examined the physiological and psychological effects of nanomolar amounts of steroids applied directly under the nose (Delta4,16-androstadien-3-one and 1,3,5,(10),16-estratetraen-3-ol). These potential human chemosignals were not consciously discernible in a strong-odor carrier (clove oil and propylene glycol). In a double-blind, within-subject,(More)
The human chemosignal, Delta 4,16-androstadien-3-one modulates psychological state without being consciously discernible as an odor. This study demonstrates that Delta 4,16-androstadien-3-one (androstadienone) alters cerebral glucose utilization both in subcortical regions and in areas of the neocortex not exclusively associated with olfaction. These widely(More)
An increased intramyocellular lipid (IMCL) content, as quantified by (1)H-magnetic resonance spectroscopy ((1)H-MRS), is associated with reduced insulin sensitivity. At present, it is unclear which factors determine IMCL formation and how rapidly IMCL accumulation can be induced. We therefore studied the impact of hyperinsulinemia and elevated circulating(More)
Recently, a 1H-MRS method became available to quantify intramyocellular lipids (IMCL) non-invasively. Currently, little is known about the regulation of this lipid pool. During prolonged exercise of moderate intensity, non-plasma-derived fatty acids play an important role as an energy source; lipids located within the skeletal muscle are considered to be a(More)
The existence of metabolically relevant intramyocellular lipids (IMCL) as assessed by the noninvasive (1)H-magnetic resonance spectroscopy (MRS) has been established. In the present studies, we analyzed the relationships between IMCL in two muscle types [the predominantly nonoxidative tibialis muscle (tib) and the predominantly oxidative soleus muscle(More)
BACKGROUND Endothelial dysfunction (ED) is regarded as an early step in the development of atherosclerosis. Among the pathogenetic factors leading to atherosclerosis, the role of insulin resistance and hyperinsulinemia as independent risk factors is still under debate. In this study, we examined the association between ED and insulin resistance in(More)
Insulin resistance of skeletal muscle glucose uptake is a prominent feature of Type II diabetes (NIDDM); therefore pharmacological interventions should aim to improve insulin sensitivity. Alpha-lipoic acid (CAS 62-46-4, thioctic acid, ALA), a natural occurring compound frequently used for treatment of diabetic polyneuropathy, enhances glucose utilization in(More)
Alpha-lipoic acid (ALA), a naturally occuring compound and a radical scavenger was shown to enhance glucose transport and utilization in different experimental and animal models. Clinical studies described an increase of insulin sensitivity after acute and short-term (10 d) parenteral administration of ALA. The effects of a 4-week oral treatment with(More)
In population surveys, blood pressure and plasma insulin concentration are related variables, but the association is confounded by age and obesity. Whether insulin resistance is independently associated with higher blood pressure in normal subjects is debated. We analyzed the database of the European Group for the Study of Insulin Resistance, made up of(More)