Melatonin was determined in serum and cerebrospinal fluid (CSF) obtained from 13 healthy males lumbar-punctured in the sitting position without preceding bed rest. There was a significant correlation between the levels of melatonin in serum and the CSF. The serum concentration was lower than that in the CSF, a finding that calls in question the theory that melatonin is mainly released from the pineal gland into the bloodstream. In conclusion, serum levels of melatonin in healthy male volunteers, mirror the CSF concentrations when lumbar puncture is carried out using the described technique.

The single-step, fast spray-drying process may represent a valuable alternative to the multistep, time-consuming freeze-drying process in the area of formulation and processing of biopharmaceuticals. In this study, we tested the use of sucrose and hydroxypropyl-beta-cyclodextrin (HP-beta-CD) as stabilizing excipients in the spray-drying of a model protein, beta-galactosidase. The solutions were processed using a Büchi 190 cocurrent Mini Spray Dryer at an outlet temperature of 61 +/- 2 degrees C. The powders were redissolved and analyzed for catalytic activity, aggregation, chemical decomposition, and thermal susceptibility as observed by high-resolution calorimetry. Spray-drying significantly inactivated beta-galactosidase. Spray-drying beta-galactosidase in the presence of sucrose did not prevent inactivation. However, after spray-drying beta-galactosidase in the presence of HP-beta-CD, or HP-beta-CD and sucrose, full catalytic activity was exhibited on reconstitution. Furthermore, the reconstituted product was unchanged in terms of molecular weight, charge, and thermal stability. These findings are consistent with a hypothesis that the change responsible for inactivation of beta-galactosidase was mainly a monomolecular, noncovalent change, i. e., the formation of incorrect structures, that arose from surface denaturation. This study clearly demonstrates that cyclodextrins can be useful stabilizing excipients in the preparation of spray-dried protein pharmaceuticals.

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Haematological parameters, iso-transferrin ratio in plasma and serotonin uptake in platelets were studied in 10 men (age range 21-54 years) with occupational long-term, low level exposure to vapours from epoxy paints. The control group consisted of 10 healthy men (age range 20-48 years) not occupationally exposed to chemicals or organic solvents. The mean cellular volume of erythrocytes was significantly higher for the house painters than the controls (p less than 0.05). The plasma concentration of iso-transferrin with isoelectric point 5.7 (Tf5.7) and the ratio between Tf5.7 and total transferrin (Tftot) were significantly higher in the exposed group (p less than 0.05). The uptake of serotonin in platelets (Vmax) from the exposed workers was significantly lower than the values for the controls (p less than 0.01). The results indicate an association between the observed biological effects and the chemical exposure, and we speculate that this is caused by changes in structure and function of the cell membranes.