Psychiatric aspects of parathyroid disease.

Parathyroid diseases can present with psychiatric symptoms and can be recognized through determinations of serum electrolytes, especially the calcium level. Psychiatric evaluations should include a serum calcium concentration test, which is also essential in reassessment of patients poorly responsive to mental illness treatment. A magnesium and a phosphate assay may also be diagnostically helpful. Abnormality of divalent cation levels may provide evidence for consideration of, or ruling out, parathyroid disorders. Determinations of parathyroid hormone are performed if clinically indicated, and if abnormal divalent cation quantifications are confirmed. If parathyroid disease is identified, corrective endocrine therapies may diminish or even cure psychiatric aspects of parathyroid pathology. Failure to recognize a parathyroid disorder leaves an endocrine-induced mental dysfunction without proper treatment.

Synthesis and degradation of nitrate reductase during the cell cycle of Chlorella sorokiniana.

Studies on the diurnal variations of nitrate reductase (NR) activity during the life cycle of synchronized Chlorella sorokiniana cells grown with a 7:5 light-dark cycle showed that the NADH:NR activity, as well as the NR partial activities NADH:cytochrome c reductase and reduced methyl viologen:NR, closely paralleled the appearance and disappearance of NR protein as shown by sodium dodecyl sulfate gel electrophoresis and immunoblots. Results of pulse-labeling experiments with [35S]methionine further confirmed that diurnal variations of the enzyme activities can be entirely accounted for by the concomitant synthesis and degradation of the NR protein.