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Some investigations have been done on the relationships between the swelling-shrinkage change, oxygen consumption and state of oxidation-reduction of pyridine nucleotides of mitochondria, and between the swelling-shrinkage change of mitochondrial structure by Ca2+ and accumlation of Ca45 in rat liver mitochondria. A parallel relationship is observed between the Ca2+ induced swelling and Ca2+ accumulation. Both of them require Pi but not Mg2+, ATP and exogenous respiratory substrates and are inhibited by respiratory inhihitors or uncouplers of oxidative phosphorylation but not by the inhibitors of phosphorylating respiration. In this case the Ca2+ is transported with the phosphate even in ice cold. Even in the presence of antimycin A, moreover, Pi-dependent Ca2+ accumulation and Ca2+ induced swelling can be overcome by addition of ATP, which are inhibited by oligomycin. In the presence of Pi, mitochondria show shrinkage by addition of Ca2+ before the high amplitude swelling, which is closely correlated to the electron ransport chain and phosphorylation process of mitochondria, and the pattern of the mitochondrial shrinkage is quite similar to that observed in the case of respiratory control by ADP in intact mitochondria. This shrinkage of mitochondria is inhibited by respiratory inhibitor or uncoupler of oxidative phosphorylation but not by the inhibitor of phosphorylating respiration. From these data, therefore, it is considerd that the Ca2+ accumulation and Ca2+ induced shrinkage-swelling of mitochondria require the energy of oxidative phosphorylation with respect to the initial step before the oligomycin block.

We attempted to determine the usefulness of body surface mapping (BSM) for differentiating patients with Brugada syndrome (BS) from patients with asymptomatic Brugada syndrome (ABS). Electrocardiograms (ECG) and BSM were recorded in 7 patients with BS and 35 patients with ABS. Following the administration of Ic antiarrhythmic drugs, BSM was recorded in 5 patients with BS and 16 patients with ABS. The maximum amplitudes at J0, J20, J40 and J60 were compared between the 2 groups, as were 3-dimensional maps. The maximum amplitudes at J0, J20 and J60 under control conditions were larger in patients with BS than in patients with ABS (P < 0.05). A three-dimensional map of the ST segments under control conditions in patients with BS showed a higher peak of ST elevation in the median precordium compared to that for patients with ABS. Increases in ST elevation at J20, J40 and J60 following drug administration were greater in patients with BS than in patients with ABS (P < 0.05). Evaluation of the change in amplitude of the ST segment at E5 caused by Ic drug administration was also useful for differentiating between the 2 groups. In conclusion, BSM was useful for differentiating patients with BS from those with ABS.

Epiphyseal growth cartilage of the femoral head obtained from Wistar rats was investigated after fixation by a rapid-freezing and freeze-substitution. Liquid helium was used in order to achieve a fast cooling rate without ice-crystal damage during the rapid freezing. Use of the rapid-freezing and freeze-substitution procedure provided better ultrastructural preservation of the chondrocyte than conventional chemical fixation methods. This procedure allowed a more reliable approach to electron probe analysis. X-ray microanalysis of the specimens confirmed that calcium is not detected in the initial matrix vesicles as a result of the freezing process. The results suggest that calcium release from precipitates occurs in the free state without any detectable formation of hydroxyapatite at the initial stage of calcification and that calcium is not tightly bound to the matrix vesicles.

The reaction between acatalasemia hemolysate and anti-normal erythrocyte catalase IgG gave a precipitin line which was interrupted by a normal precipitin line, in the double immunodiffusion method. Hypocatalasemia hemolysate revealed two precipitin lines, one completely, the other partially, fused with a normal precipitin line. No immunological reactions between fresh hemolysates of acatalasemia, hypocatalasemia and normal erythrocytes and antihuman C-reactive protein serum were observed, but the lysates stored for 4 weeks in an ice cold water bath reacted slightly with this antiserum.