[Short interval change of 99mTc-ethyl cysteinate dimer single photon emission computed tomography in Wilson's disease].

We studied short interval change of cranial computed tomography (CT), magnetic resonance imaging (MRI) and 99mTc-ethyl cysteinate dimer single photon emission computed tomography (99mTc-ECD SPECT) in a case of Wilson's disease. Before treatment, CT scan showed low density changes in the bilateral thalamus and basal ganglia, and MRI demonstrated high intensity in same lesions. 99mTc-ECD SPECT study revealed a hypoperfusion in bilateral thalamus. After 2 months under D-penicillamine therapy, neurological findings had improvement. Hypoperfusion in the thalamus with 99mTc-ECD SPECT significantly improved, whereas abnormal findings of CT scan and MRI persisted. 99mTc-ECD SPECT study may be useful for the planning of the treatment of Wilson's disease.

Characterization of the initial steps of precursor import into rat liver mitoplasts.

Mitochondria have two independent protein-import machineries, one in the outer membrane (the Tom system) and the other in the inner membrane (the Tim system). Here, we have characterized the initial steps of precursor import into rat liver mitoplasts. The import reaction was separated into two stages, consisting of precursor binding to the mitoplasts at 0-10 degreesC, and a subsequent chase reaction at 30 degreesC. This assay revealed four distinct precursor-import steps: DeltaPsi-dependent initial binding of the precursor, precursor transfer to the Tim23-Tim17 stage, DeltaPsi-dependent translocation of the presequence across the inner membrane, and the complete translocation of the mature portion of the precursor. Antibodies against the intermembrane space domain of Tim23 inhibited neither the precursor binding nor the subsequent translocation of the presequence across the inner membrane. In contrast, the antibodies inhibited the complete translocation of the mature domain of the precursor across the inner membrane. Immunoprecipitation with anti-Tim23 IgGs revealed that the precursor-Tim23 complex increased with time and temperature after the initial targeting of the precursor to the mitoplasts. These results suggest that the precursor is first targeted to the inner membrane component DeltaPsi-dependently, then transferred to the Tim system consisting of Tim23-Tim17, and finally imported into the matrix.

[Antioxidants and angiogenetic factor associated with age-related macular degeneration (exudative type)].

To confirm the hypothesis that antioxidants and angiogenetic factors may be associated with the development of age-related macular degeneration (exudative type), we compared serum levels of vitamins A, C, and E and carotinoid, zinc, selenium and b-FGF (basic-fibroblast growth factor) in 35 patients with age-related macular degeneration (exudative type) with the levels in 66 controls. The average serum zinc level was significantly lower in the patient group than in the control group. Serum vitamin E-alpha levels also tended to be lower. Most serum b-FGF levels were below the standard value in each group. Based on the above results, we conclude that subnormal levels of zinc and vitamin E may be associated with the development of age-related macular degeneration.

A new cytotoxic compound from a water extract of corn.

A new cytotoxic compound 2 was isolated from a water extract of corn germ. Structural elucidation by spectroscopic data and chemical evidence fully substantiated 2 to be 11 (E)-10-oxo-11-octadecen-13-olide. Compound 2 exhibited considerably strong cytotoxic activity against various cell lines with IC50 of 0.9-2.8 micrograms/ml.

Biliary and urinary excretion of metals in humans.

Fifteen metals (lead, cadmium, arsenic, inorganic mercury, organic mercury, iron, manganese, magnesium, chromium, zinc, copper, nickel, cobalt, tin, and aluminum) were determined in the hepatic bile and urine collected simultaneously from three Japanese individuals (2 males, 1 female). The presence of these metals was classified as follows: hepatic biliary concentrations were higher than urinary concentrations (lead, arsenic, and iron); urinary concentrations were higher than hepatic biliary concentrations (cadmium, inorganic mercury, tin, cobalt, magnesium, chromium, copper, zinc, and nickel); hepatic biliary concentrations were almost equal to urinary concentrations (manganese and organic mercury); and relationship between hepatic biliary and urinary concentrations changed occasionally (aluminum). Eight essential metals (iron, manganese, magnesium, zinc, chromium, copper, nickel, and cobalt) were detected at considerable concentrations in hepatic bile. Accounting for the daily flow volume of hepatic bile and the reabsorption of these metals, the supplementation of these metals should occur during treatment of diseases accompanied by loss of hepatic bile.

An automated system for the determination of lead in blood, manganese in urine and nickel in waste water.

An automated system has been developed to analyze lead in blood, manganese in urine and nickel in waste water at a rate of 20 to 30 samples per hour. The analysis is based on direct chelation without digestion, extraction into methyl isobutyl ketone and flame atomic absorption spectrophotometry. The applicability of the system in the field of occupational and environmental medicine is discussed.

Biotransformation of methylmercury in vitro.

Inorganic mercury formation from methylmercury by the mouse liver and kidney was studied in vitro. With chopped liver or kidney, inorganic mercury was formed from added methylmercury, but when the tissue was homogenized, the activity was diminished. Equimolar addition of selenium had no effect on the reaction.