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Einheit von Park und Architektur : der Park am IG Hochhaus
Cerebellar granule cells, which constitute half the brain's neurons, supply Purkinje cells with contextual information necessary for motor learning, but how they encode this information is unknown. Here we show, using two-photon microscopy to track neural activity over multiple days of cerebellum-dependent eyeblink conditioning in mice, that granule cell populations acquire a dense representation of the anticipatory eyelid movement. Initially, granule cells responded to neutral visual and somatosensory stimuli as well as periorbital airpuffs used for training. As learning progressed, two-thirds of monitored granule cells acquired a conditional response whose timing matched or preceded the learned eyelid movements. Granule cell activity covaried trial by trial to form a redundant code. Many granule cells were also active during movements of nearby body structures. Thus, a predictive signal about the upcoming movement is widely available at the input stage of the cerebellar cortex, a
Circadian variation in tamoxifen pharmacokinetics in mice and breast cancer patients
The anti-estrogen tamoxifen is characterized by a large variability in response, partly due to pharmacokinetic differences. We examined circadian variation in tamoxifen pharmacokinetics in mice and breast cancer patients. Pharmacokinetic analysis was performed in mice, dosed at six different times (24-h period). Tissue samples were used for mRNA expression analysis of drug-metabolizing enzymes. In patients, a cross-over study was performed. During three 24-h periods, after tamoxifen dosing at 8 a.m., 1 p.m., and 8 p.m., for at least 4Â weeks, blood samples were collected for pharmacokinetic measurements. Differences in tamoxifen pharmacokinetics between administration times were assessed. The mRNA expression of drug-metabolizing enzymes showed circadian variation in mouse tissues. Tamoxifen exposure seemed to be highest after administration at midnight. In humans, marginal differences were observed in pharmacokinetic parameters between morning and evening administration. Tamoxifen Cmax and area under the curve (AUC)0â8Â h were 20Â % higher (PÂ max was shorter (2.1 vs. 8.1Â h; PÂ =Â 0.001), indicating variation in absorption. Systemic exposure (AUC0â24Â h) to endoxifen was 15Â % higher (PÂ <Â 0.001) following morning administration. The results suggest that dosing time is of marginal influence on tamoxifen pharmacokinetics. Our study was not designed to detect potential changes in clinical outcome or toxicity, based on a difference in the time of administration. Circadian rhythm may be one of the many determinants of the interpatient and intrapatient pharmacokinetic variability of tamoxifen
ANK3 related neurodevelopmental disorders: expanding the spectrum of heterozygous loss-of-function variants
ANK3 encodes multiple isoforms of ankyrin-G, resulting in variegated tissue expression and function, especially regarding its role in neuronal development. Based on the zygosity, location, and type, ANK3 variants result in different neurodevelopmental phenotypes. Autism spectrum disorder has been associated with heterozygous missense variants in ANK3, whereas a more severe neurodevelopmental phenotype is caused by isoform-dependent, autosomal-dominant, or autosomal-recessive loss-of-function variants. Here, we present four individuals affected by a variable neurodevelopmental phenotype harboring a heterozygous frameshift or nonsense variant affecting all ANK3 transcripts. Thus, we provide further evidence of an isoform-based phenotypic continuum underlying ANK3-associated pathologies and expand its phenotypic spectrum.Genetics of disease, diagnosis and treatmen
Body image in patients with somatoform disorder
BACKGROUND: Although body-related problems are common in patients with somatoform disorder, research focusing on how patients with somatoform disorder perceive and evaluate their body is scarce. The present study compared differences in body image between patients with somatoform disorder and respondents from a general population sample. It also examined differences within the somatoform disorder group between men and women and between the diagnostic subgroups conversion disorder, pain disorder and undifferentiated somatoform disorder. METHODS: Data were obtained from 657 patients (67.5% female) with somatoform disorder (DSM-IV-TR 300.7, 300.11, 300.81, 300.82) and 761 participants (58.6% female) from the general population. The Dresden Body Image Questionnaire (DBIQ) was used to assess body image in five domains: body acceptance, vitality, physical contact, sexual fulfilment, and self-aggrandizement. Confirmatory factor analysis and analyses of variance were performed. Since differences in age and sex were found between the somatoform disorder sample and the comparison sample, analyses were done with two samples of 560 patients with somatoform disorder and 351 individuals from the comparison sample matched on proportion of men and women and age. RESULTS: Patients scored significantly lower than the comparison sample on all DBIQ domains. Men scored higher than women. Patients with conversion disorder scored significantly higher on vitality and body acceptance than patients with undifferentiated somatoform disorder and pain disorder. CONCLUSIONS: The mostly large differences in body image between patients with somatoform disorder and the comparison sample as well as differences between diagnostic subgroups underline that body image is an important feature in patients with somatoform disorder. The results indicate the usefulness of assessing body image and treating negative body image in patients with somatoform or somatic symptom disorder
Genetic and phenotypic characterization of NKX6â2ârelated spastic ataxia and hypomyelination
Background and purpose
Hypomyelinating leukodystrophies are a heterogeneous group of genetic disorders with a wide spectrum of phenotypes and a high rate of genetically unsolved cases. Biâallelic mutations in NKX6â2 were recently linked to spastic ataxia 8 with hypomyelinating leukodystrophy.
Methods
Using a combination of homozygosity mapping, exome sequencing, and detailed clinical and neuroimaging assessment a series of new NKX6â2 mutations in a multicentre setting is described. Then, all reported NKX6â2 mutations and those identified in this study were combined and an inâdepth analysis of NKX6â2ârelated disease spectrum was provided.
Results
Eleven new cases from eight families of different ethnic backgrounds carrying compound heterozygous and homozygous pathogenic variants in NKX6â2 were identified, evidencing a high NKX6â2 mutation burden in the hypomyelinating leukodystrophy disease spectrum. Our data reveal a phenotype spectrum with neonatal onset, global psychomotor delay and worse prognosis at the severe end and a childhood onset with mainly motor phenotype at the milder end. The phenotypic and neuroimaging expression in NKX6â2 is described and it is shown that phenotypes with epilepsy in the absence of overt hypomyelination and diffuse hypomyelination without seizures can occur.
Conclusions
NKX6â2 mutations should be considered in patients with autosomal recessive, very early onset of nystagmus, cerebellar ataxia with hypotonia that rapidly progresses to spasticity, particularly when associated with neuroimaging signs of hypomyelination. Therefore, it is recommended that NXK6â2 should be included in hypomyelinating leukodystrophy and spastic ataxia diagnostic panels
Arabidopsis latent virus 1, a comovirus widely spread in Arabidopsis thaliana collections
Transcriptome studies of Illumina RNA-Seq datasets of different Arabidopsis thaliana natural accessions and T-DNA mutants revealed the presence of two virus-like RNA sequences which showed the typical two-segmented genome characteristics of a comovirus. This comovirus did not induce any visible symptoms in infected A.âthaliana plants cultivated under standard laboratory conditions. Hence it was named Arabidopsis latent virus 1 (ArLV1). Virus infectivity in A.âthaliana plants was confirmed by quantitative reverse transcription polymerase chain reaction, transmission electron microscopy and mechanical inoculation. Arabidopsis latent virus 1 can also mechanically infect Nicotiana benthamiana, causing distinct mosaic symptoms. A bioinformatics investigation of A.âthaliana RNA-Seq repositories, including nearly 6500 Sequence Read Archives (SRAs) in the NCBI SRA database, revealed the presence of ArLV1 in 25% of all archived natural A.âthaliana accessions and in 8.5% of all analyzed SRAs. Arabidopsis latent virus 1 could also be detected in A.âthaliana plants collected from the wild. Arabidopsis latent virus 1 is highly seed-transmissible with up to 40% incidence on the progeny derived from infected A.âthaliana plants. This has probably led to a worldwide distribution in the model plant A.âthaliana with as yet unknown effects on plant performance in a substantial number of studies
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