Neural effects of cognitive-behavioural therapy on dysfunctional attitudes in depression.

BACKGROUND: Dysfunctional attitudes are a feature of depression that has been correlated with receptor binding abnormalities in limbic and cortical regions. We sought to investigate the functional neuroanatomy of dysfunctional attitudes in major depressive disorder (MDD) and the effects of treatment with cognitive-behavioural therapy (CBT). METHOD: Participants were 16 patients with unipolar depression in an acute depressive episode (mean age 40.0 years) and 16 matched healthy controls (mean age 39.9 years). Patients were medication free and received a course of treatment with CBT. All participants underwent functional magnetic resonance imaging (fMRI) scans at baseline and at week 16, prior to the initiation of therapy and following the course of CBT for patients. During each fMRI scan, participants indicated their attributions to statements from a modified Dysfunctional Attitudes Scale (mDAS-48). RESULTS: MDD patients in an acute depressive episode endorsed a greater number of extreme responses to DAS statements, which normalized following CBT treatment. Extreme attributions were associated with greater activation in the left hippocampal region, inferior parietal lobe and precuneus in MDD patients as compared with healthy controls as a main effect of group. An interaction effect was found in the left parahippocampal region, which showed less attenuation in MDD patients at the follow-up scan relative to healthy controls. CONCLUSIONS: Attenuation of activity in the parahippocampal region may be indicative of an improvement in dysfunctional thinking following CBT treatment in depression, while persistent engagement of regions involved in attentional processing and memory retrieval with extreme attributions reflects a trait feature of depression.

The ultrastructure of Penicillium chrysogenum in the course of benzyl-penicillin biosynthesis.

The find structures of high- and low-yield mutants of Penicillium chrysogenum, producing 100 and 10,000 units/ml of penicillin G, were compared. The cells of both mutants demonstrated a typical eukaryotic ultrastructure. In the cytoplasm nuclei, mitochondira, lipid bodies, endoplasmic reticulum, and Golgi vesicles were observed. In the cells of high-yield mutant, during the biosynthesis of penicillin, the number of lipid bodies decreased. It is possible that the lipids are metabolized in the process of biosynthesis of penicillin. In the cytoplasm more multivesicular bodies and small vesicles, about 40 nm in diameter, could be seen. These Golgi vesicles, present in largest number in cells of high-yield mutant, fuse with the cell membrane and play an important role in the transport of penicillin from the cytoplasm to the cell environment. The cell walls of the high-yield mutant become three times thicker during the antibiotic biosynthesis. No comparable changes were observed in the ultrastructure of the low-yield mutant. The cell wall thickness did not increase, the cytoplasm contained few Golgi vesicles only, and the lipid bodies can be seen in all cells.

The site of benzyl penicillin accumulation in Penicillium chrysogenum.

Benzyl penicillin was localized in cells of Penicillium chrysogenum by means of enzymatical and immunological methods, enabling the determination of minute amounts of penicillin. The reactions were performed on ultrathin sections. They allow to determine the antibiotic inside of the cells. The results indicate that benzyl penicillin is present in the vesicles belonging to the Golgi apparatus. Benzyl penicillin is transported from the cytoplasm outside the cell membrane by the Golgi vesicles.