Arytenoid adduction for unilateral vocal cord paralysis

The arytenoid adduction technique was devised and performed under local anesthesia on five patients with unilateral vocal cord paralysis. It is especially indicated for the case of a wide, glottal chink and a difference in the level of the two cords. The muscle process is pulled by two 3-0 nylon sutures in simulation of the functions of the lateral cricoarytenoid muscle and the lateral thyroarytenoid muscle. Improvement of voice after surgery was dramatic in all of the patients who were operated on. The surgical procedure is rather simple, easy, and allows adjustment of the degree of arytenoid adduction during surgery to produce the best voice obtainable.

Colchicine-like effect of diethylstilbestrol (DES) on mammalian cells in vitro

Diethylstilbestrol (DES), a synthetic estrogen, showed colchicine-like effects in vitro on cells of the cell lines such as Chinese hamster fibroblast of thymus origin (CHT), rat liver (DL), rat erythroblastic leukemia (EDEN-1/TC) and HeLa-S3. Metaphase arrest was induced 3 h after treatment with 15 microgram/ml of DES and polyploid or polynucleated cells were prominently observed more than 24 h after treatment. The arrest, however, was reversible when the agent was removed from the medium. Tetraploid karotypes induced by DES in CHT cells consisted of all double sets of diploid chromosome constitution except one chromosome marker. By clonal selection, several hypotetraploid sublines were successfully isolated from a CHT cell population after the treatment with 15 microgram/ml of DES for 48 h. Some comparative studies of cytological effects of DES with those induced by colcemid indicated that the DES effect was also a mitotic inhibition similar to colchicine.

Common bile duct obstruction by hepatoma

Two cases of hepatoma are presented in which the clinical manifestations of biliary obstruction resulted from growth of hepatoma into the extrahepatic bile duct. Recognition of such a manifestation of the hepatoma may allow for surgical extirpation of the tumor combined with radiation therapy, which may result in long survival.

A central inhibitory action of 5-hydroxytryptamine in the leech

Previous studies indicated that 5-HT reduced the number of spontaneous excitatory junctional potentials (ejp's) that occurred in leech body wall muscle cells. The present study confirms these findings and shows that the ejp's arise from impulses in motoneuron L. This study further shows that 5-HT acts by hyperpolarizing and reducing the membrane resistance of neuron L, thus inhibiting the motoneuron and reducing the frequency of spontaneous ejp's on body wall muscle cells. These effects of 5-HT are not seen when the ganglion is bathed in a high magnesium solution, a finding that suggests that 5-HT does not act directly on the membrane of motoneuron L. This study demonstrates that 5-HT can have a central inhibitory effect on body wall muscle contractions. Previous studies provide evidence that 5-HT may act as a direct neuromuscular inhibitory transmitter and may also take part in peripheral presynaptic inhibition. Thus, if further studies confirm these suggestions, the well-known inhibitory effect of 5-HT on leech body wall muscle is a more complex process than was previously thought.

The identification of two inhibitory cells in each segmental ganglion of the leech and studies on the ionic mechanism of the inhibitory junctional potentials produced by these cells

The present study identifies a pair of inhibitory cells that are located on each anterolateral margin of a leech segmental ganglion. These cells, which we label as cells 119, are electrically interconnected. These cells give rise to inhibitory junctional potentials (ijp's) in contralteral longitudinal body wall muscle cells. The latencies of the ijp's following spikes in cell 119 are variable. The ijp's are caused by transient increases in premeability to the Cl- ion. Previous studies demonstrated that 5-HT causes a hyperpolarization of body wall muscle cells by increasing the permeability of muscle membrane to the Cl- ion. Accordingly, 5-HT was searched for in the 119 cell bodies, but autoradiography, fine structure, and gas chromatography-mass spectrometry gave no indication that 5-HT was present in these cells. However, the variable latencies of the ijp's may indicate that there is a neuron interposed between cell 119 and the muscle cells. If this is the case, then the interposed neuron should be analyzed for 5-HT. Further experiments to locate the terminals of cells 119 and the cell bodies of the presumed interposed neurons are thus desirable.

Reverse plaque formation by hog cholera virus of the GPE-strain inducing heterologous interference

A simple and rapid plaque procedure was developed for the assay of hog cholera virus (HCV) of a particular strain, GPE-, based on its intrinsic interference with vesicular stomatitis virus (VSV) on the primary swine testicle cells and on an established swine kidney cell line; the procedure is called the reverse plaque formation (RPF) method. The plaques were produced as colonies of HCV-infected cells which were VSV-sensitive, disintegrated cell sheet. These plaques became visible after 15 to 20 h of superinfection with VSV done 2 days after an initial inoculation of the GPE- strain. The plaque formation was inhibited by a specific antiserum against HCV. All cells within the plaque had HCV antigen detectable by fluorescent-antibody staining. The variations of reverse plaque count were low enough to permit virus titration. The relationship between virus concentration and the number of plaques was essentially linear. The titer measured by the RPF method was a little higher than that of the tube culture interference method.

The late results of terminal esophagoproximal gastrectomy (TEPG) with intensive devascularization and splenectomy for bleeding esophageal varices in cirrhosis

The operative procedure of terminal esophagoproximal gastrectomy (TEPG) with extensive esophagogastric devascularization and splenectomy is described in detail and its rationale is discussed. Late results of this operation performed therapeutically on 64 patients with posthepatitic cirrhosis revealed that (1) operative mortality rate (death within a month) was 11%, mostly being contributed by poor-risk patients; (2) over-all survival was 65% at 5 years and 59% at 10 years; (3) gastrointestinal bleeding recurred in nine patients, five of whom had major and four minor hemorrhages; (4) portasystemic encephalopathy was seen frequently after shunts had never occurred, and the hepatic encephalopathy was only a sequel of major gastrointestinal bleeding or a manifestation of terminal-stage liver insufficiency; and (5) ascites was not a major clinical problem after this operation; mild esophagitis was an occasional complication.

Anatomical basis for an apparent paradox concerning conduction velocities of two identified axons in Aplysia

Larger axons usually have faster conduction velocities, lower thresholds, and larger extracellular action potentials than smaller axons. However, it has been shown that the largest fiber, R2, in the right pleurovisceral connective of the marine mollusc, Aplysia, has a higher threshold and a slower conduction velocity than does the smaller axon of cell RI, even though the amplitude of R2's spike is larger than R1's spike. One explanation of this apparent parodox is that the two axons have different "intrinsic membrane and axoplasmic constants" (Goldman, L. (1961), J. Cell Comp. Physiol. 57: 185-191). However, the deep infolding of R2's axonal membrane suggested that differences in the shape of the two axons might also account for the paradox. Accordingly, we measured the conduction velocities of the two axons and then examined the same axons in the electron microscope in order to measure their volumes and surface areas. Our morphological observations indicate that the extensive infolding of surface membrane causes R2 to have a smaller volume to surface area ratio than R1. Thus, since conduction velocity is proportional to the square root of the volume to surface area ratio (Hodgkin, A.L. (1954), J. Physiol. 125: 221-224), it is predictable that the smaller axon would have a faster conduction velocity. The results suggest that the paradoxical conduction velocities can be explained largely as resulting from differences in the shapes of the two axons. However, certain discrepancies between the measured and the predicted values suggest that other factors are contributing as well.

Effects of disulfide bond reduction on the excitatory and inhibitory postsynaptic responses of Aplysia ganglion cells

Three kinds of the cholinoceptive neurons, nicotinic depolarizing (D)-, nicotinic hyperpolarizing (H)-, and muscarinic H-tyes, as well as two other kinds of neurons, GABA H- and dopamine H-types, were identified in Aplysia abdominal ganglion, and the effects of disulfide bond reduction and reoxidation on their postsynape acetylcholine-induced responses of both nicotinic types (D- and H-) were depressed by reducing the disulfide bonds with dithiothreitol (DTT) and restored by reoxidizing with 5, 5' -dithiobis-(2-nitrobenzoic acid): (DTNB), whereas the responses of the muscarinic H-, GABA H-, and dopamine H-cells were not affected at all by either DTT or DTNB. In contrast to the results obtained from the electroplax, the cholinergic receptors in our preparation showed neither the activation by hexamethonium nor the augmentation of decamethonium-induced responses after reduction of disulfide bonds. In addition, our preparation did not demonstrate the long-lasting responses to bromoaTT-induced depression of the nicotinic responses was studied on the dose-response curves; the mode of receptor inhibition was rather complexed, being neither type of competitive nor non-competitive. We concluded that the disulfide bond is a crucial element in both types of nicotinic receptors (D and H), and that this bond is related to the activation process of the receptors regardless of their ionic specificities.

Ionic mechanism of 5-hydroxytryptamine induced hyperpolarization and inhibitory junctional potential in body wall muscle cells of Hirudo medicinalis

Five-hydroxytryptamine (5-HT) causes a hyperpolarization and increased conductance of the leech body wall muscle cell membrane. If 5-HT is applied in the absence of the Cl minus ion, the response appears as a depolarization, whereas if 5-HT is applied in the absence of the K+ ion, the response is a hyperpolarization. In both cases, the conductance of the muscle cell membrane is increased. Stimulation of the peripheral nerve to the body wall muscle produces a complex junctional potential in muscle cells. Exposing the muscle to d-tubocurarine (d-TC) eliminates the excitatory component (EJP) of the complex potential. The inhibitory potential (IJP) that remains has an equilibrium potential at approximately 65 mV. Furthermore, this IJP appears as a depolarization when the nerve is stimulated in the presence of d-TC and low CL minus, whereas this is not the case if the nerve is stimulated in the presence of d-TC and low K+. The drugs BOL-148 and cyproheptadine block the IJP's in the body wall muscle. These data are interpreted as indicating that 5-HT acts on leech body wall muscle cells by increasing the conductance to the Cl minus ion and that the IJP's caused by nerve stimulation are probably the result of 5-HT release at nerve terminals. As a final point, it has been shown that the inhibition by 5-HT of the spontaneous EJP's that occur on the leech body wall muscle results from an inhibition of central neurons and not from any direct effect on the muscle cell or on peripheral synapses.

[Faculty rotation following fractures of the shaft of femur in childhood]

Follow-up of 31 out of 40 children with fractures of the femoral shaft. There were 28 instances of faulty rotation. Its clinical importance, prevention and correction are discussed.

The effect of dimethyl sulfoxide on the neuronal excitability and cholinergic transmission in Aplysia ganglion cells

The effects of DMSO on single nerve cells of Aplysia were investigated by various electrophysiological methods. 1. Although the increase in permeability of the biological membranes produced by DMSO has been well documented, we found that DMSO at concentration of less than 20% actually decreases the permeability of the neuronal membranes, probably toward potassium and chloride ions. This change in ionic permeability reversibly depolarizes the resting membranes and makes the neurons more excitable. 2. The falling phase of the spike is prolonged by 8% DMSO, because it blocks the active increase in potassium permeability. This change suppresses the high frequency discharge, because the refractory period of each spike is increased. Neither the rising phase nor the absolute firing level is appreciably altered by DMSO when these are examined after the depolarization is cancelled. 3. Dilute DMSO (less than 1%) facilitates cholinergic trasmission because it blocks ACh-esterase activity. DMSO at concentrations of more than 10% ultimately blocks cholinergic transmission entirely, because it also depresses cholinoceptive receptor activity (probably by allosteric interaction). The action of 1-10% DMSO is complicated, because both facilitatory and inhibitory effects take place at the same time. 4. In cholinergic synapses, excitatory transmission is more susceptible to DMSO than inhibitory transmission. This is because the activity of the excitatory receptor is blocked more readily than that of the inhibitory receptor. The depressing effects of DMSO are not specific to the cholinergic system, however, since the activities of GABA and glutamate receptors are similarly depressed.

Analysis of hyperpolarizations induced by glutamate and acetylcholine on Onchidium neurones

1. Four giant neurones, designated G-H cells, in the right pleural ganglion of the marine pulmonate mollusc, Onchidium verruculatum, showed characteristic membrane hyperpolarization during applications of either acetylcholine (ACh) or L-glutamate. In the presence of ACh the membrane was hyperpolarized only transiently, while in the presence of glutamate the response was maintained. Significant increases in membrane conductance accompanied the changes in membrane potential.2. In excess potassium sea water, a slight hyperpolarization occurred when the normal concentration was increased between one- and twofold. However, depolarization usually occurred when the concentration was increased tenfold except on a few occasions when a slight but definite hyperpolarization occurred. These changes were all accompanied by a substantial increase in the membrane conductance. This hyperpolarization was in all probability the result of an increase in chloride ion permeability caused by the release of an ACh-like transmitter from depolarized presynaptic nerve terminals.3. The reversal levels for glutamate- and ACh-induced hyperpolarization respectively were approximately - 20 and - 17 mV with respect to the resting membrane potential.4. By changing the external ion composition, glutamate- and ACh-induced hyperpolarization were shown to be the result of an increased permeability of the subsynaptic membrane to potassium and chloride ions respectively. It appears therefore that inhibition in the same G-H cells can be activated by two different transmitter substances and that each of them activates a change in the membrane permeability to a different ion.5. The relationship between the concentration of glutamate and the membrane conductance change was suggestive of two glutamate molecules reacting with a single receptor site.