Reconstruction of the distal foot dorsum with a distally based extensor digitorum brevis muscle flap.

We have successfully applied a reverse flow island flap of extensor digitorum brevis muscle for coverage of tissue defects in the distal portion of the foot dorsum in 2 patients. This flap covered the metatarsophalangeal area well with cadaver limb dissection and seems useful to cover the defect in the distal foot dorsum.     

Periodic alternating nystagmus and rebound nystagmus in spinocerebellar ataxia type 6.

We report on a family with ataxia type 6 (SCA6) showing peculiar oculomotor symptoms. The proband presented with periodic alternating nystagmus (PAN), and her 2 brothers had rebound nystagmus and gaze-evoked nystagmus. They carried the identical mutation (the number of expanded CAG repeat, 24) in the CACNA1A gene. The intrafamilial variability of oculomotor symptoms may be ascribed to factors other than CAG repeat expansion size in SCA6.     

Early seizures after acute ischemic stroke]

In order to determine predictive factors of early seizures (ES) after acute stroke and to estimate prognosis, we retrospectively examined clinical data of 1,743 consecutive patients with acute ischemic stroke. The subjects were divided into two groups; an ES group (19 patients) and a non-ES group (1,724 patients). Multivariate statistical analysis revealed that the NIH-Stroke Scale score on admission (/10, OR, 1.1: 95% CI 1.04 to 1.13) and positive past history of cerebrovascular disease or brain injury (OR, 3.85: 95% CI 1.49 to 9.95) are significant factors to predict ES. There was no significant difference in the outcome between the two groups. A recurrence of seizures, after follow up for 4 to 40 months, was observed only in one patient with a history of ES.     

Technique of intramedullary fixation for arthrodesis of the wrist in rheumatoid arthritis.

We did 18 arthrodeses of the wrist in 16 patients with rheumatoid arthritis using an intramedullary fixation technique. There were 15 women and one man, whose ages at operation ranged from 47 to 71 years (mean 58). Follow up ranged from 13 to 68 months (mean 27). The operative technique consists of a combination of intramedullary placement of two Kirschner (K)-wires and an autogenous bone graft. At follow up bony union was apparent in all cases. K-wires came out of the metacarpal joints in two cases. Paraesthesiae in the median nerve distribution occurred in two cases which both recovered within three months.     

Antibodies to beta 2-microglobulin, the light-chain component of class I histocompatibility molecules, provide an activation signal to human lymphocytes

Antibodies to beta 2-microglobulin (beta 2m), the light-chain component of class I histocompatibility antigens, provide a strong co-stimulatory signal to human lymphocytes in the presence of phorbol ester. This activation signal requires a high concentration of antibody, whereas the effect on responses to a mitogenic lectin is exclusively inhibitory over a broad dose range. A rabbit polyclonal and a mouse monoclonal antibody to beta 2m were similarly co-stimulatory. Antibody to beta 2m was co-stimulatory with phorbol ester, but not calcium ionophore, suggesting that class I antigens play a role in the initiation of the 'first' signal of a recently described two-signal model of lymphocyte activation.     

FIBER TYPE DIFFERENTIATION AND MYOSIN EXPRESSION IN REGENERATING RAT MUSCLES

The relation between fiber type differentiation and the expression of slow and fast myosin isoforms was examined in regenerating rat muscles after injection of a myotoxic agent, bupivacaine. The histochemical myosin ATPase reaction for fiber typing demonstrated that immature type 2C fibers differentiated into type 1, 2A and 2B fibers. Slow and fast myosin isoforms were demonstrated immunohistochemically using antibodies raised against myosins extracted from the slow-twitch soleus and fast-twitch tensor fasciae latae muscles of mature guinea pigs (anti-SOL, anti-TFL). The results showed that immature type 2C fibers destined to differentiate into type 1 fibers first reacted with anti-TFL only, and later reacted with both anti-TFL and anti-SOL, whereas those destined to differentiate into type 2A and 2B fibers reacted with anti-TFL only throughout regeneration. The significance of the myosin isoforms that react with anti-TFL in immature type 2C fibers was discussed. ACTA PATHOL. JPN. 37: 1537-1547, 1987.     

Presynaptic muscarinic and alpha-adrenoceptor-mediated regulation of GABA release from myenteric neurones of the guinea-pig small intestine.

The effects of cholinomimetic and sympathomimetic drugs on the release of [3H]-gamma-aminobutyric acid ([3H]-GABA) evoked by high K+ from the isolated small intestine of the guinea-pig were investigated, in the presence of tetrodotoxin. Acetylcholine and oxotremorine, at concentrations ranging from 10(-9) to 10(-6) M inhibited the evoked release of [3H]-GABA in a concentration-dependent manner, while nicotine was without effect. Scopolamine and pirenzepine inhibited the effect of oxotremorine, while hexamethonium had no effect. The IC50 values for scopolamine and pirenzepine of the oxotremorine (3 X 10(-8) M)-induced inhibition were 1.02 X 10(-9) M and 9.78 X 10(-10) M, respectively. Noradrenaline, but not isoprenaline inhibited the evoked release of [3H]-GABA. Clonidine (10(-10)-10(-6) M) reduced the evoked release of [3H]-GABA in a concentration-dependent manner, but phenylephrine had no effect. The inhibitory effect of clonidine was antagonized by yohimbine but not by prazosin. These findings provide evidence for the localization of M1-muscarinic and alpha 2-adrenoceptors on GABAergic nerve terminals and their involvement in the presynaptic control of the release of GABA from the guinea-pig small intestine.     

Interaction of potassium channel openers and blockers in canine atrial muscle.

1. The possibility that the interaction between potassium channel openers, e.g. cromakalim, pinacidil and nicorandil, and some potassium channel blockers involves a common site was investigated in canine atrial muscle. 2. Cromakalim, pinacidil and nicorandil produced a negative inotropic effect, their pD2 (-log EC50) values being 6.11 +/- 0.07, 5.37 +/- 0.09 and 4.55 +/- 0.07, respectively. 3. The potassium channel blockers, tetraethylammonium (TEA), tetrabutylammonium (TBA), 3,4-diaminopyridine (DAP), CsCl and BaCl2 all produced a positive inotropic effect. 4. The concentration-effect curves for the negative inotropic actions of pinacidil were shifted in a parallel way to the right by low concentrations of TEA, TBA or BaCl2. Maximum responses to pinacidil were depressed by higher concentrations of the blockers. An analysis of the non-competitive antagonism by TEA yielded pKA (-log KA) values of 4.00-4.05 for pinacidil. 5. The concentration-effect curves for cromakalim and nicorandil were shifted by TEA similarly to those for pinacidil, and a similar analysis yielded pKA values of 4.47-4.68 for cromakalim and 3.47-3.74 for nicorandil. 6. The KA values of cromakalim, pinacidil and nicorandil were about 10-30 times greater than their EC50 values, indicating that there are non-linear stimulus-effect relationships between the binding of the three potassium channel openers to their binding sites at potassium channels and their negative inotropic effects. 7. The dissociation constants for TEA could also be estimated from pA2 and pKB values for antagonizing competitively and non-competitively the negative inotropic effects of the three potassium channel openers; they were 3.47-3.89, and did not differ between the potassium channel openers. 8. The concentration-effect curves for the three potassium channel openers were not affected by DAP or CsCl. 9. These results suggest the following: (i) quaternary ammonium compounds like TEA and TBA antagonize the negative inotropic effect of cromakalim, pinacidil and nicorandil by binding to potassium channels, thus preventing binding of the channel openers to the same sites or closely related sites in canine right atrial muscles.