Modulation of motorcortical excitability by methylphenidate in adult voluntary test persons performing a go/nogo task.

This study investigated the interaction between motorcortical excitability (short interval cortical inhibition, intracortical facilitation and long interval cortical inhibition), different requirement conditions [choice reaction test (CRT), attention/go/nogo], and their pharmacological modulation by methylphenidate (MPH) in normal healthy adults (n = 31) using a transcranial magnetic stimulation paradigm. MPH was administered in a dosage of 1 mg/kg body weight, maximum 60 mg. Additionally, serum level and clearance of MPH were controlled. The statistical analysis of variance revealed a significant three-way interaction of 2 (MPH) x 3 (CRT) x 6 (ISI) predicting motor evoked potential amplitudes (P = 0.032, MPH none and full dose, n = 31). In order to compare effects of dosage an additional between-subjects factor (half vs. full MPH dose) was introduced. None of the interactions involving this between-subject factor reached statistical significance. Exploring interactions with MPH only, a 3 (MPH none, half and full dose) x 3 (CRT) x 6 (ISI) analysis of variance revealed significant two-way interactions for MPH x ISI (P = 0.040) and condition x ISI (P < 0.001, n = 18). Effects observed for MPH were strongest on facilitatory processes, weaker for intracortical inhibition. In sum, MPH seems to interact via striato-thalamo-cortical pathways with original motorcortical processes (ISI), to a lesser extent with task-dependent or behavioral parameters (CRT).

[An unusual form of craniofacial dysmorphism with mechanical respiratory disturbances in newborns (author's transl)]. / Eine Sonderform der kraniofazialen Dysmorphie mit mechanisch bedingter Atemstörung bei Neugeborenen.

Gross and histologic findings at autopsy of a one week old newborn baby with respiratory distress and mechanical obstacles to adequate intubation revealed a variation of the craniofacial dysmorphy syndrome: hypoplasia of the mandible combined with dysplastic and hypoplastic tongue and complete situs inversus. The tongue consisted of an hypoplastic smooth anterior part and a hypertrophic posterior part with the usual papillae. Both parts were separated by a deep sulcus across the middle of the tongue with a predominantly fibrous amuscular bottom. Because of this anomaly the posterior part of the tongue was retracted covering the orifice of the larynx and thus causing the respiratory distress. The lesion is discussed in context with data of similar syndromes.