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The nitration of methylnaphthalenes with NO(2)BF(4) and NOBF(4) was examined in order to shed light on the controversial aromatic nitration mechanism, electrophilic vs charge-transfer process. The NO(2)(+) nitration of 1,8-dimethylnaphthalene showed a drastic regioselectivity change depending on the reaction temperature, where ortho-regioselectivity at -78 degrees C and para-regioselectivity at 0 degrees C were considered to reflect the electrophilic and the direct or alternative charge-transfer process, respectively, because the NO(+) nitration through the same reaction intermediates as in the NO(2)(+) nitration via a charge-transfer process resulted in para-regioselectivity regardless of the reaction temperature. The NO(2)(+) nitration of redox potential methylnaphthalenes higher than 1,8-dimethylnaphthalene gave a similar ortho-regioselectivity enhancement to 1,8-dimethylnaphthalene at lower temperature, thus reflecting the electrophilic process. On the other hand, the NO(2)(+) nitration of redox potential methylnaphthalenes lower than 1,8-dimethylnaphthalene showed para-regioselectivity similar to the NO(+) nitration, indicating the direct or alternative charge-transfer process. In the presence of strong acids where the direct charge-transfer process will be suppressed by protonation, the ortho-regioselectivity enhancement was observed in the NO(2)(+) nitration of 1,8-dimethylnaphthalene, suggesting that the direct charge-transfer process could be the main process to show para-regioselectivity. These experimental results imply that the NO(2)(+) nitration proceeds via not only electrophilic but also direct charge-transfer processes, which has been considered to be unlikely because of the high energy demanding process of a bond coordination change between NO(2)(+) and NO(2). Theoretical studies at the MP2/6-31G(d) level predicted ortho- and para-regioselectivity for the NO(2)(+) nitration via electrophilic and charge-transfer processes, respectively, and the preference of the direct charge-transfer process over the alternative one, which support the experimental conclusion

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Prolonged evacuation of [{Pt(CO)(3)}(2)](2+) (1), the first homoleptic, dinuclear, cationic platinum(I) carbonyl complex, results in reversible disproportionation. Complex 1 was formed by dissolution of PtO(2) in concentrated H(2)SO(4) under an atmosphere of CO [Eq. (a)], and completely characterized by NMR ((13)C, (195)Pt), IR, and Raman spectroscopy.

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We report three cases of clinically diagnosed corticobasal degeneration: a 63-year-old male, a 63-year-old female and a 62-year-old female. All the three patients exhibited asymmetric limb-kinetic apraxia and extrapyramidal signs. Neuroimaging studies with MRI, 123I-IMP SPECT and FDG-PET were performed in each of the three cases and FDOPA-PET was performed in patient 1. MRI analysis showed asymmetric cortical atrophy, especially in the parietal cortex, in all the three cases. 123I-IMP SPECT analysis revealed asymmetric reduction of the cerebral blood flow, in accordance with the MRI findings. FDG-PET analysis showed marked asymmetric reduction (> or = 10%) of cerebral metabolic rates for glucose (CMRGlc) in the lateral frontal cortex, lateral posterior frontal cortex and primary motor and sensory cortex in all the patients, although the asymmetry in the thalamus which had been described as a characteristic CBD finding in previous reports was not observed in any of the patients in our study. FDOPA-PET analysis revealed reduction of uptake in both the putamen and caudate nucleus, predominantly in the caudate nucleus, which suggests that the FDOPA-PET findings correlate with the extrapyramidal signs observed in the case of the 63-year-old male.

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We compared survival patterns in 61 medically treated and 78 surgically treated patients at a Japanese community hospital. The 2 groups were matched for presence of significant 3 vessel disease, resting ejection fraction of more than 40%, a bypassable left anterior descending artery, sex, and age. All surgical patients received saphenous vein grafts. The patients treated surgically had better 5 and 9 years survival rates than the medically treated patients (93% and 85% vs 74% and 55%, respectively; p < 0.01 by Cox-Mantel analysis). Five and 9 years rates of absence of ischemic events (non-fatal myocardial infarction and primary cardiac death) were also better in the surgical group than the medical group (92% and 87% vs 66% and 52%, respectively; p < 0.001). Of the surgically treated patients, 5 died perioperatively, 3 had late cardiac deaths and 2 had a nonfatal infarction. Among the medically treated patients, 16 had cardiac deaths, and 6 had non-fatal infarctions. Although our study was non-randomized, we have shown an advantage for surgical treatment of patients with 3-vessel coronary disease.

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We have observed two cases suffered from left thalamic hemorrhage, that showed pure agraphia. The first case was a 49 year-old, right handed male, who was educated through 11th grade. The CT scan revealed left thalamic hemorrhage with ventricular casting. The second case was a 48 year- old, right handed male, who was educated through 9th grade. The CT scan revealed left thalamic hemorrhage which is smaller than that of the first case, without intraventricular rupture. With a standard neuropsychological evaluation performed at chronic stage, neither cases showed oral language disorder, apraxia and agnosia. On the Wechsler Adult Intelligence Scale, total IQ of the first and second case were 71 and 80 respectively. Each case developed severe writing disorder. The first case showed severe neographism and scrawl, mild literal paragraphia, which were frequently accompanied with perseveration. The second case showed literal paragraphia and no response, but neographism was not detected. The common characteristics of both cases were; 1) intact copy writing. 2) discrepancy between difficulty in writing "Kana" and that in "Kanji". 3) anosognosia of agraphia. The cerebral blood flow study by 123I-IMP Single photon emission computed tomography revealed low perfusion of the left cerebral hemisphere in both cases. From these findings, we concluded that dysfunction of the left cerebral cortex is responsible for producing agraphia in these cases.

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The gene coding for four subunits of cytochrome aa3-type oxidase was isolated from a genomic DNA library of the thermophilic bacterium PS3 and sequenced. The N-terminus of each subunit was also sequenced to verify the initiation site of the reading frame. The deduced amino acid sequences contained 615 amino acid residues for subunit I (CO1/caaB product), 333 residues for subunit II (CO2/caaA product), 207 residues for subunit III (CO3/caaC product), and 109 residues for subunit IV (CO4/caaD product) after processing. Re-examination of the sequencing of caa revealed a longer open reading frame for CO1, which contains 14 transmembrane segments instead of 12 [Sone et al. (1988) J. Biochem. 103, 606-610], although the main portions of the sequences constituting cytochrome a (FeA), cytochrome a3 (FeB), and CuB are correct. PS3 CO2 has an additional sequence for cytochrome c after the CuA binding protein portion with 2 transmembrane segments, which is homologous to the mitochondrial counterpart. PS3 CO3 has DCCD-binding glutamyl residues but contains only 5 transmembrane segments, unlike the mitochondrial counterpart, which has 7 segments. The subunits of PS3 cytochrome oxidase (aa3-type) show clear similarity in amino acid sequences with those of cytochrome bo-type oxidase from Escherichia coli as well, in spite of the difference of hemes. PS3 CO3 and CO4 are much more similar to E. coli CO3 and CO4 than to mitochondrial CO3 and CO4, respectively.

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A new putative subunit was found in cytochrome c oxidase (aa3-type) of the thermophilic bacterium PS3. The N-terminal amino acid sequence of this approximately 12 kDa protein coincides with the deduced sequence of an open reading frame found downstream from the gene encoding subunit I of the PS3 cytochrome oxidase [(1988) J. Biochem. 103, 606-610]. This small hydrophobic protein, composed of 109 amino acid residues after the initial methionine residue has been processed, shows homology with the subunit IV (cyoD product) of cytochrome bo-type quinol oxidase of Escherichia coli.

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A 64-year-old male patient of amyotrophic lateral sclerosis (ALS) with frozen gait, axial rigidity and supranuclear upper gaze palsy was reported. We have followed this patient more than four years. He was well until November 1982, when he noticed weakness of left arm. In March 1983, he noticed hypogeusia and in July, he developed dysarthria and frozen gait. On admission, he was alert and oriented. Neurological examination revealed dysarthria, dysphagia and muscular weakness and atrophy in bilateral upper extremities, dominantly in left side. He showed remarkable frozen gait, retropulsion and could not walk. Brain CT showed mild dilatation of the third ventricle. In August 1988, he showed tongue atrophy, and weakness and atrophy of the extremities progressed during these four years. He also showed axial rigidity and frozen gait. Brain CT showed severe third ventricular dilatation and atrophy of tegmentum of the midbrain and cerebellum that were compatible with progressive supranuclear palsy (PSP). Six months later, he developed upper gaze palsy. From these findings, we concluded that this patient had a quite unique clinical features of both ALS and PSP.

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