Introducing a novel approach of network oriented analysis of ERPs, demonstrated on adult attention deficit hyperactivity disorder.

OBJECTIVE: Introducing a network-oriented analysis method (brain network activation [BNA]) of event related potential (ERP) activities and evaluating its value in the identification and severity-grading of adult ADHD patients. METHODS: Spatio-temporal interrelations and synchronicity of multi-sited ERP activity peaks were extracted in a group of 13 ADHD patients and 13 control subjects for the No-go stimulus in a Go/No-go task. Participants were scored by cross-validation against the most discriminative ensuing group patterns and scores were correlated to neuropsychological evaluation scores. RESULTS: A distinct frontal-central-parietal pattern in the delta frequency range, dominant at the P3 latency, was unraveled in controls, while central activity in the theta and alpha frequency ranges predominated in the ADHD pattern, involving early ERP components (P1-N1-P2-N2). Cross-validation based on this analysis yielded 92% specificity and 84% sensitivity and individual scores correlated well with behavioral assessments. CONCLUSIONS: These results suggest that the ADHD group was more characterized by the process of exerting attention in the early monitoring stages of the No-go signal while the controls were more characterized by the process of inhibiting the response to that signal. SIGNIFICANCE: The BNA method may provide both diagnostic and drug development tools for use in diverse neurological disorders.

Parasitologic and serologic observations of infection with Pneumocystis in humans.

More than 500 specimens of lung tissue were examined for Pneumocystis. Of the 38 infections detected, most were in immunodeficient patients. Samples of serum from approximately 600 healthy normal subjects and 117 children with acute lymphatic leukemia were examined by an indirect fluorescent antibody test. The age-related data from the normal children suggested that nearly 100% of children are infected with Pneumocystis during the first two years of life. Groups of patients with leukemia who had symptoms of pneumocystis pneumonia had significantly higher titers of IgG antibody than groups of patients with leukemia who did not have clinical symptoms and normal subjects. Nevertheless, the diagnostic value of the indirect fluorescent antibody test is limited, but serologic follow-up study can be useful. Groups of children with leukemia had lower mean titers of IgM antibody regardless of their clinical condition.

Hemorrhagic hypotension and the lung: in vitro respiration.

We examined the O2 consumption and respiratory quotient of lung slices from rats whose mean blood pressure was decreased to approximately 40 mm Hg for 1 hour by hemorrhage and from control rats that were handled in the same manner but were not bled. The in vitro O2 consumption of lung slices from the hypotensive rats was lower than the O2 consumption of slices from control rats; exogenous glucose did not alter these differences. In the absence of exogenous glucose, the (mean +/- SE) respiratory quotient of lungs from control rats was 0.75 +/- 0.01; from hypotensive rats 0.78 +/- 0.01 (P less than 0.05). Glucose increased the respiratory quotient of lung slices from control rats to 0.95 +/- 001 but increased the respiratory quotient of slices from hypotensive rats to only 0.86 +/- 0.01. We concluded that hemorrhagic hypotension decreases lung O2 consumption and alters substrate metabolism by the lung.