Social animals show reduced physiological responses to aversive events if a conspecific is physically present. Although humans are innately social, it is unclear whether the mere physical presence of ...another person is sufficient to reduce human autonomic responses to aversive events. In our study, participants experienced aversive and neutral sounds alone (alone treatment) or with an unknown person that was physically present without providing active support. The present person was a member of the participants' ethnical group (ingroup treatment) or a different ethnical group (outgroup treatment), inspired by studies that have found an impact of similarity on social modulation effects. We measured skin conductance responses (SCRs) and collected subjective similarity and affect ratings. The mere presence of an ingroup or outgroup person significantly reduced SCRs to the aversive sounds compared with the alone condition, in particular in participants with high situational anxiety. Moreover, the effect was stronger if participants perceived the ingroup or outgroup person as dissimilar to themselves. Our results indicate that the mere presence of another person was sufficient to diminish autonomic responses to aversive events in humans, and thus verify the translational validity of basic social modulation effects across different species.
Functional Near Infrared Spectroscopy (fNIRS) may be a suitable, simple, and cost-effective brain imaging technique for detecting divergent neuronal patterns at an early stage of neurodegeneration. ...In course of Mild Cognitive Impairment (MCI) or Alzheimer's disease (AD), a deficit in visual-spatial processing, located in the parietal cortex, is a reliable risk factor. Earlier, we established the application of the clock-hand-angle-discrimination task (ADT) during fNIRS to identify neuronal correlates of the visual-spatial processing in a healthy elderly sample. In this analysis, we aimed to measure and find out differences in the hemodynamic response in MCI participants compared to matched healthy controls. As expected, MCI participants showed more errors over all conditions of pointer length and a higher reaction time in the long and middle pointer length condition. Moreover, results revealed a significant reduction of cortical activation in MCI patients. There was a generally increased activity in both the right as compared to the left hemisphere and the superior parietal brain region as compared to the inferior parietal brain region in both groups. In summary, fNIRS can be implemented in the measurement of visual-spatial processing in MCI patients and healthy elderly based on ADT. MCI participants had difficulties to cope with the ADT. Since neuronal hypoactivity occurs with concomitant behavioral deficits, an additional analysis was performed on a subgroup of MCI patients who performed as well as the control group in behavior. This subgroup analysis also showed a hypoactivation of the parietal cortex, without evidence of a compensatory activation. Therefore, we assume that MCI patients are characterized by a deficit in the parietal cortex. Overall, these findings confirm our hypothesis that hemodynamic deficits in visual-spatial processing, localized in the parietal cortex, are reliable and early diagnostic markers for cognitive decline in risk groups for the development of AD.
Previous results demonstrated that
and
gene variants affect serum concentrations of antidepressants. We implemented a PGx service determining gene variants in
and
in our clinical routine care and ...report on our first patient cohort.
We analysed
and
allele, genotype, and phenotype frequencies, and actionable pharmacogenetic variants in this German psychiatric inpatient cohort. Two-tailed
-test was used to investigate for differences in
and
phenotypes and actionable/non-actionable genetic variant frequencies between our cohort and reference cohorts.
Out of the 154 patients included, 44.8% of patients were classified as CYP2D6 normal metabolizer, 38.3% as intermediate metabolizers, 8.4% as poor metabolizers, and 2.6% as ultrarapid metabolizers. As for CYP2C19, 40.9% of patients were classified as normal metabolizers, 19.5% as intermediate metabolizers, 2.6% as poor metabolizers, 31.2% as rapid metabolizers, and 5.8% as ultrarapid metabolizers. Approximately, 80% of patients had at least one actionable PGx variant.
There is a high prevalence of actionable PGx variants in psychiatric inpatients which may affect treatment response. Physicians should refer to PGx-informed dosing guidelines in carriers of these variants. Pre-emptive PGx testing in general may facilitate
also for other drugs metabolised by CYP2D6 and/or CYP2C19.
Abstract
The implementation of pharmacogenomic (PGx) testing in psychiatry remains modest,
in part due to divergent perceptions of the quality and completeness of the
evidence base and diverse ...perspectives on the clinical utility of PGx testing
among psychiatrists and other healthcare providers. Recognizing the current lack
of consensus within the field, the International Society of Psychiatric Genetics
assembled a group of experts to conduct a narrative synthesis of the PGx
literature, prescribing guidelines, and product labels related to psychotropic
medications as well as the key considerations and limitations related to the use
of PGx testing in psychiatry. The group concluded that to inform medication
selection and dosing of several commonly-used antidepressant and antipsychotic
medications, current published evidence, prescribing guidelines, and product
labels support the use of PGx testing for 2 cytochrome P450 genes (
CYP2D6,
CYP2C19
). In addition, the evidence supports testing for human leukocyte
antigen genes when using the mood stabilizers carbamazepine (
HLA-A and
HLA-B
), oxcarbazepine (
HLA-B
), and phenytoin (CYP2C9, HLA-B). For
valproate, screening for variants in certain genes (
POLG, OTC, CSP1
) is
recommended when a mitochondrial disorder or a urea cycle disorder is suspected.
Although barriers to implementing PGx testing remain to be fully resolved, the
current trajectory of discovery and innovation in the field suggests these
barriers will be overcome and testing will become an important tool in
psychiatry.
The factors determining gradients of biodiversity are a fundamental yet unresolved topic in ecology. While diversity gradients have been analysed for numerous single taxa, progress towards general ...explanatory models has been hampered by limitations in the phylogenetic coverage of past studies. By parallel sampling of 25 major plant and animal taxa along a 3.7 km elevational gradient on Mt. Kilimanjaro, we quantify cross-taxon consensus in diversity gradients and evaluate predictors of diversity from single taxa to a multi-taxa community level. While single taxa show complex distribution patterns and respond to different environmental factors, scaling up diversity to the community level leads to an unambiguous support for temperature as the main predictor of species richness in both plants and animals. Our findings illuminate the influence of taxonomic coverage for models of diversity gradients and point to the importance of temperature for diversification and species coexistence in plant and animal communities.
The effects of an i.p. administration of cyclohexyladenosine (CHA) have been examined upon ischemic brain damage in gerbils. Ischemia was induced for 20 min by occlusion of both carotid arteries, and ...CHA was administered 5 min after recirculation at a dose of 2 mg/kg. Animals were sacrificed either 1, 3 or 6 days after ischemia and their brains were used for examination of cell morphology and quantitative autoradiography. In animals subject to ischemia, the deterioration of the laminar organization of the hippocampus was associated with a significant decrease in adenosine A1-receptors (labeled with 3HCHA), G-protein (labeled with 3Hforskolin). The treatment with CHA considerably improved the morphological preservation of cells in the CA1 region of the hippocampus and prevented the reduction in the specific binding of all radioligands. Adenosine, its analogues and other substances modulating adenosine receptors may thus provide new therapeutic approaches to the treatment of ischemia-induced brain injury.
Psychopathological alterations associated with symmetrical basal ganglia sclerosis have been well characterized. A preponderance of a so-called organic affective syndrome has been reported (König ...1989), but schizophrenic syndromes have also been described, in particular in young patients (Cummings et al 1983). Symmetrical basal ganglia sclerosis may be secondary to ischemia, hypoxia, trauma, intoxications, inflammations, or hyporesp. pseudohypoparathyroidism. Among idiopathic forms sporadic as well as familial ones with dominant and recessive inheritance have been observed (Billard et al 1989).
Alzheimer’s disease (AD) and Mild Cognitive Impairment (MCI) are a globally rising issue. It is necessary to detect such diseases early to find strategies for prevention. Typically, patients with MCI ...or AD show deviant neuronal patterns, which could be detected early through brain imaging techniques enabling assumptions about pre-existing diseases. Functional Near-Infrared Spectroscopy (fNIRS) is an appropriate imaging method because of its easy and economical nature with hardly any drawbacks. An early measurable risk factor indicating neurodegenerative processes could be a deficit in visual-spatial processing, which is localized in the parietal cortex. In this study, we aimed to measure the hemodynamic response of the visual-spatial processing in the healthy elderly participants of our long-term Vogel Study with fNIRS during the clock-hand-angle-discrimination task (ADT) to deepen our understanding of healthy brain mechanisms. Our results revealed for our healthy sample a significantly increased neuronal brain activity with increasing task difficulties, namely from the long to the middle to the short clock hand during ADT and significantly higher activation in the right hemisphere compared to the left hemisphere as well as in the superior parietal cortex compared to the inferior parietal cortex. Additionally, our behavioral data demonstrated longer reaction times and more errors with an increasing task requirement. We, therefore, assume that visual-spatial processing can successfully be operationalized with fNIRS for healthy elderly people based on ADT. Further fNIRS analyses are planned to investigate pathological neuronal correlates of visual-spatial function in MCI or AD study participants.
•Parietal cortex activation during visual-spatial tasks can be measured with fNIRS.•Visual-spatial processing can be measured using angle discrimination tasks.•Significant activation of the parietal cortex can be found in healthy elderly.•Higher task requirement results in an increased (right-lateral) neuronal activity.•Higher task requirement results in higher reaction times and more errors.
To complement analogous studies using conventional ligand-membrane binding assays, the densities of gamma-aminobutyric acid and benzodiazepine receptors in the brain have been assessed using an ...autoradiographic technique in an animal model of hepatic encephalopathy. Hepatic encephalopathy due to fulminant hepatic failure was induced in rabbits by the intravenous injection of galactosamine. The specific binding of three radiolabeled ligands was assessed densitometrically in several microregions of cerebral cortex, hippocampus and cerebellum. 3HMuscimol was used to assess gamma-aminobutyric acid receptor density and 3Hflunitrazepam or 3HRo 15-1788 was used to assess benzodiazepine receptor density. No significant differences were observed between the magnitude of binding of the three ligands to each of the microregions of brain from control rabbits and rabbits in Stage III or IV hepatic encephalopathy. These findings suggest that the behavioral expression of hepatic encephalopathy in the model studied is not dependent upon an increase in the number of gamma-aminobutyric acid or benzodiazepine receptors, but do not conflict with the hypothesis that gamma-aminobutyric acid-ergic tone is increased in hepatic encephalopathy.
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