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Katrin Schulze

Publications and source records attributed to Katrin Schulze.

9 recordsLinked to original sources
PubMed2006

Neural correlates of absolute pitch differ between blind and sighted musicians.

Several reports have indicated a higher incidence of absolute pitch in blind than in sighted musicians. Employing a pitch memory task, we examined whether a blind absolute pitch musician would rely on different neural correlates than a group of sighted absolute pitch musicians. The blind musician showed significantly more activation of bihemispheric visual association areas, lingual gyrus, parietal and frontal areas than the sighted musicians. Sighted musicians showed more activation of the right primary auditory cortex and the cerebellum when compared with the blind musician. These differences in the activation pattern suggest the use of a different neural network including visual association areas while performing pitch categorization and identification in this blind musician in comparison with sighted musicians.

Acoustic Stimulation↗
PubMed2005

Kinetics of the ATP hydrolysis cycle of the nucleotide-binding domain of Mdl1 studied by a novel site-specific labeling technique.

We have recently proposed a "processive clamp" model for the ATP hydrolysis cycle of the nucleotide-binding domain (NBD) of the mitochondrial ABC transporter Mdl1 (Janas, E., Hofacker, M., Chen, M., Gompf, S., van der Does, C., and Tampé, R. (2003) J. Biol. Chem. 278, 26862-26869). In this model, ATP binding to two monomeric NBDs leads to formation of an NBD dimer that, after hydrolysis of both ATPs, dissociates and releases ADP. Here, we set out to follow the association and dissociation of NBDs using a novel minimally invasive site-specific labeling technique, which provides stable and stoichiometric attachment of fluorophores. The association and dissociation kinetics of the E599Q-NBD dimer upon addition and removal of ATP were determined by fluorescence self-quenching. Remarkably, the rate of ATP hydrolysis of the wild type NBD is determined by the rate of NBD dimerization. In the E599QNBD, however, in which the ATP hydrolysis is 250-fold reduced, the ATP hydrolysis reaction controls dimer dissociation and the overall ATPase cycle. These data explain contradicting observations on the rate-limiting step of various ABC proteins and further demonstrate that dimer formation is an important step in the ATP hydrolysis cycle.

ATP-Binding Cassette Transporters↗
PubMed2005

Prevalence of chlamydiae in boars and semen used for artificial insemination.

Although there are indications for venereal transmission of chlamydiae in pigs, direct diagnostic evidence on the presence of these bacteria in boars and boar semen in particular is still incomplete. We investigated boars from two studs (A, B) in semen (A: n = 174; B: n = 100) and faeces (A: n = 174; B: n = 24) for chlamydiae using ompA-PCR and partial ompA gene sequencing. Additionally, blood serum was examined for chlamydial antibodies using an indirect ELISA (A: n = 171; B: n = 62). Chlamydiae were found in 9 (5.2%) and 24 (24.0%) semen specimens, and in 71 (40.1%) and 2 (8.3%) faecal samples from boars of stud A and B, respectively. Regarding individual chlamydial species, Chlamydophila psittaci and Chlamydia suis were identified most frequently, with the former predominating in semen (in 23 out of 33 positive samples) and the latter in faeces (68/73). In contrast, Chlamydophila pecorum was found only sporadically. Chlamydial antibodies were detected in 80 (46.8%) and 6 (9.7%) boars of stud A and B, respectively. No correlation was observed between the data from serology and PCR of semen or faeces in either of the studs. In conclusion, detection of chlamydiae in semen of boars suggests a potential for venereal transmission. Whether the high overall prevalence of chlamydial infections reflects a general situation in boars needs to be investigated. Serological testing failed to identify boars shedding chlamydiae in their semen.

Animals↗
PubMed2005

Treatment-outcome for synchronous head-and-neck and oesophageal squamous cell carcinoma.

BACKGROUND AND PURPOSE: Although head & neck and oesophageal carcinomas occur synchronously in up to 12%, almost no data on feasibility and outcome after radiotherapy are available. MATERIALS AND METHODS: From 1989 to 2002, 24 patients were treated at Tuebingen University and Fulda hospital with a radiation based, curative approach. These were analyzed retrospectively. RESULTS: The median overall survival was 37 (1-69) months with a few long-term survivors with a median follow-up of 26 months for patients at risk. 7 local recurrences occurred. No major toxicity was seen. DISCUSSION: Even though the prognosis of synchronous head & neck and oesophageal carcinomas is grim, long-term survival is possible. A radiation-based approach is feasible and can be chosen for a curative treatment approach which we recommend.

Aged↗
PubMed2005

Adults and children processing music: an fMRI study.

The present study investigates the functional neuroanatomy of music perception with functional magnetic resonance imaging (fMRI). Three different subject groups were investigated to examine developmental aspects and effects of musical training: 10-year-old children with varying degrees of musical training, adults without formal musical training (nonmusicians), and adult musicians. Subjects made judgements on sequences that ended on chords that were music-syntactically either regular or irregular. In adults, irregular chords activated the inferior frontal gyrus, orbital frontolateral cortex, the anterior insula, ventrolateral premotor cortex, anterior and posterior areas of the superior temporal gyrus, the superior temporal sulcus, and the supramarginal gyrus. These structures presumably form different networks mediating cognitive aspects of music processing (such as processing of musical syntax and musical meaning, as well as auditory working memory), and possibly emotional aspects of music processing. In the right hemisphere, the activation pattern of children was similar to that of adults. In the left hemisphere, adults showed larger activations than children in prefrontal areas, in the supramarginal gyrus, and in temporal areas. In both adults and children, musical training was correlated with stronger activations in the frontal operculum and the anterior portion of the superior temporal gyrus.

Acoustic Stimulation↗
PubMed2004

Music, language and meaning: brain signatures of semantic processing.

Semantics is a key feature of language, but whether or not music can activate brain mechanisms related to the processing of semantic meaning is not known. We compared processing of semantic meaning in language and music, investigating the semantic priming effect as indexed by behavioral measures and by the N400 component of the event-related brain potential (ERP) measured by electroencephalography (EEG). Human subjects were presented visually with target words after hearing either a spoken sentence or a musical excerpt. Target words that were semantically unrelated to prime sentences elicited a larger N400 than did target words that were preceded by semantically related sentences. In addition, target words that were preceded by semantically unrelated musical primes showed a similar N400 effect, as compared to target words preceded by related musical primes. The N400 priming effect did not differ between language and music with respect to time course, strength or neural generators. Our results indicate that both music and language can prime the meaning of a word, and that music can, as language, determine physiological indices of semantic processing.

Acoustic Stimulation↗
PubMed2004

Amygdala-kindling induces alterations in neuronal density and in density of degenerated fibers.

Kindling is characterized by a progressive intensification of seizure activity culminating in generalized seizures following repeated administration of an initially subconvulsive electrical or chemical stimulus. Since it is known that epilepsy induces morphological alterations in the limbic system, we examined the neuropathological consequences of kindling with a sensitive silver-staining method for the visualization of damaged neurons and Nissl staining for the estimation of the neuronal densities in different limbic areas. Wistar rats implanted with electrodes in the left basolateral nucleus were stimulated until 15 consecutive stage V seizures (scale of Racine). Amygdala-kindled animals had reduced cell density in the amygdala and increased density of fragments of degenerated axons. Reduced neuronal density and the occurrence of degenerated axons in kindled animals were more prominent in the ipsilateral than in the contralateral hemisphere. In addition, more degenerated axons were found in cortical structures of kindled than sham-operated animals. These results indicate that kindling induced morphological alterations that were not restricted to either the ipsilateral hemisphere or the stimulated region. These morphological changes might be responsible for the emotional and behavioral disturbances that can accompany epilepsy.

Amygdala↗
PubMed2002

Intermanual transfer in a simple motor task.

The present study examines the effects of a four-week training session in a pegboard task on uni- and bimanual performance. Of particular interest was whether practice transfer from the trained to the untrained hand takes place. Twenty-five consistently right-handed subjects were trained to perform the task with the dominant hand, or the subdominant hand, or with both hands. After this training, the learning effects for the trained and untrained hands were analysed. To summarise, we obtained the following findings: (1) After training, movement times were considerably reduced for all hands and for all training conditions (practice effects); (2) practice effects were found for the hand trained and also for the untrained hand; (3) there was not a great difference in the size of the practice effects for the right hand after left hand training or for the left hand after right hand training; (4) task difficulty had no clear influence on the practice effect; (5) and finally, we discovered that bimanual movements not only profit from bimanual training but also from unimanual training and conversely unimanual movements benefit from bimanual training. These findings are discussed in the context of different motor control models and in the light of recent brain imaging findings.

Adolescent↗