Intrafascicular decompression in the treatment of causalgia with special reference to the mechanism

A new concept of the pathogenesis of causalgia is suggested in accordance with experimental and clinical work. Endoneural hypertension secondary to nerve trunk disruption is incriminated and intrafascicular decompression is used as the key therapeutic measure. In 14 patients with causalgia thus treated, all except 1 were cured. No symptomatic recurrence was noted in a 4- to 6-year follow-up study.

Free musculocutaneous flap transfer of extensor digitorum brevis muscle by microvascular anastomosis for restoration of function of thenar and adductor pollicis muscles

This article reports 3 cases of surgical restoration of function of the thenar muscle and the adductor pollicis muscle of the thumb with free musculocutaneous flaps of the extensor digitorum brevis muscle of the toe by microsurgical technique. Two years' follow-up revealed good functional recovery of the hand with normal electromyographic findings and grade 3-4 muscular power.

Amelioration of photic injury in rat retina by ascorbic acid: a histopathologic study

It has been postulated that ascorbic acid may help to protect the retina from oxidative insult by light. To confirm this hypothesis, the authors compared light-damaged retinas of rats with or without ascorbate supplement by morphologic and morphometric studies at different time periods after light exposure. No dramatic morphologic differences were observed in the photoreceptor-retinal pigment epithelium complex between the two groups six hr after light exposure to 200 to 250-foot candles of visible light. Six to 13 days after 24 hr of exposure, the retina of rats that received ascorbate supplement showed significantly less severe damage than the retina of unsupplemented rats. The superior and temporal quadrants of the retina appeared to be most susceptible to the light damage when comparing rats with or without ascorbate supplement. These findings suggested that ascorbate ameliorates the photic injury in rat retina.

The protective effect of ascorbate in retinal light damage of rats

Cyclic light and dark-reared rats were exposed to intense visible light for various periods and then rhodopsin-measured following recovery in darkness for up to 14 days. Animals were injected with ascorbic acid or ascorbate derivatives at various doses prior to light exposure in green Plexiglas chambers. The results show that ascorbic acid administration elevates retinal ascorbate and reduces the loss of rhodopsin and photoreceptor cell nuclei resulting from intense light. When given in comparable doses, L-ascorbic acid, sodium ascorbate, and dehydroascorbate were equally effective in preserving rhodopsin. The ascorbate protective effect in the retina is also dose dependent in both cyclic light and dark-reared rats and exhibits a requirement for the L-stereoisomer of the vitamin. Ascorbic acid is effective when administered before, but not after, light exposure, suggesting that protection from light damage in the retina occurs during the light period. In some experiments, rod outer segments were isolated from rats immediately after light exposure, lipids extracted, and fatty acid composition determined. As judged by the preservation of rod outer segment docosahexaenoic acid in rats given ascorbate, the vitamin may act in an antioxidative fashion by inhibiting oxidation of membrane lipids during intense light.

Presence of a membrane-bound acetylcholinesterase form in a preparation of nerve endings from Torpedo marmorata electric organ

We adapted a method, originally described by Israel et al. (1976) for the preparation of cholinergic nerve endings from Torpedo, to deal with a larger quantity of electric tissue. We followed the distribution of acetylcholine (ACh), ATP, acetylcholine receptor (AChR), choline acetyltransferase (ChAT), ouabain-resistant and -sensitive ATPase, lactate dehydrogenase (LDH), and acetylcholinesterase (AChE), and obtained a nerve ending fraction, without detectable contamination by postsynaptic components. This preparation consisted of closed structures of 1-5 micrometers diameter, containing synaptic vesicles. It had the capacity to synthetize and release ACh. This preparation is therefore quite suitable for biochemical analysis of presynaptic elements. We particularly investigated its content of AChE: it consists exclusively of the 6S dimeric, hydrophobic form of the enzyme. This enzyme is enriched in the nerve ending preparation, by a factor higher than that obtained for ChAT. The yields obtained for the two enzymes suggest that the hydrophobic 6S AChE form may be mostly presynaptic in Torpedo electric organs. We characterized this form as a membrane-bound, externally active enzyme in the nerve ending preparation. It may thus participate in the hydrolysis of extracellularly liberated AChE, and its abundance suggests that presynaptic AChE could play an essential role in cholinergic transmission in Torpedo electric organs and perhaps also in other cholinergic synapses.