Conduit repairs of transposition complexes. A report of 14 cases

Of 14 patients with transposition complexes undergoing conduit repairs, 10 had complete transposition of the great arteries (TGA) and 4 double-outlet right ventricle. All 14 had ventricular septal defect (VSD). Ten had pulmonary stenosis, one had an atrial septal defect, and one had patent ductus arteriosus. The ages of the patients ranged from 13 months to 18 years. Six patients were treated with nine palliative operations: four systemic-pulmonary artery shunts, three atrioseptectomies, and two pulmonary banding procedures. Four patients died immediately after the operation. Among the 10 operative survivors, there were no late deaths during the follow-up periods from 5 months through 6 years. Review of the factors influencine the early operative results has stressed the importance of correct timing of operation with or without palliative treatment, increased surgical experience, and the critical evaluation of intracardiac anatomy.

Effects of N-methylamino acids and convulsants on spontaneous action potentials in guinea-pig cerebellar slices

1. N-methyl-gamma-aminobutyrate (N-methylGABA), N-methylglycine, N-methyltaurine and N-methylbeta-alanine diminished the frequency of spontaneous spike discharges in guinea-pig cerebellar slices. Usually a weak excitatory effect preceded the inhibition. 2. The inhibitory effects of N-methylGABA and N-methylbeta-alanine were competitively antagonized by both picrotoxin and strychnine. 3. The inhibitory action of N-methyltaurine was competitively suppressed by strychnine and by low concentrations of picrotoxin. 4. The inhibitory action of N-methylglycine was suppressed by strychnine but not by picrotoxin. The suppression was competitive at low concentrations of strychnine. 5. N-methylDL-glutamate brought about a strong inhibition followed by a strong excitation of the neurones. The inhibitory effects were competitively suppressed by both picrotoxin and strychnine. Neither convulsant affected the excitation. 6. Whereas L- or D-glutamate caused only excitation in the majority of cells examined, a small proportion of the cells exhibited inhibition preceding the excitation by L- or D-glutamate. Such inhibitory effects were suppressed by picrotoxin but not by strychnine. 7. Kinetic analyses of the dose-response curves for the N-methylamino acid in the presence or absence of the convulsant indicated that the number of molecules of the amino acid combining with the receptor site to produce a response was 3 for N-methylGABA, 2 for N-methylglycine, 3 for N-methyltaurine, 3 for N-methylbeta-alanine. The corresponding value was 1 for N-methylDL-glutamate (inhibition). The number of molecules of convulsant combining with the receptor site was calculated to be 2 for picrotoxin with N-methylGABA, N-methylbeta-alanine and N-methylDL-glutamate and 1 for strychnine with all N-methylamino acids examined.

Formation and function of Vibrio parahaemolyticus lateral flagella

Formation of the lateral flagella (L-flagella) of Vibrio parahaemolyticus was studied immunologically, using specific antiserum against L-flagella. On solid medium, L-flagella were formed at both high (37 degrees C) and low (25 degrees C) temperatures, although at high temperatures they became dissociated from the cells and decomposed in the medium. L-flagella were not formed in liquid or soft-agar medium. Formation of L-flagella was decreased by lowering the pH of the medium and repressed by transferring the cells from solid medium to liquid medium. Mutants possessing L-flagella but not a polar monotrichous flagellum (M-flagellum) swarmed on solid medium, whereas mutants were grown on solid medium and then transfered to liquid medium, the cells oscillated until they lost L-flagella. It is postulated that L-flagella are locomotive organelles on solid medium and in some cases also in liquid medium, whereas M-flagella are locomotive organelles only in liquid medium.

Synthetic, cross-linked polypentapeptide fo tropoelastin: an anisotropic, fibrillar elastomer

Physical properties of the cross-linked polypentapeptide of tropoelastin are reported along with chemical characterization of key intermediates in its synthesis. 220 MHz proton magnetic resonance spectra are reported on the constituent pentamers and their respective high polymers which verify structural and conformational integrity. Scanning electron microscopy of the cross-linked material formed without orientation and with flow orientation is reported. The former demonstrates the inherent fibrillar and anisotropic nature of the synthetic product. Stress-strain studies show the cross-linked polypentapeptide to exhibit elastomeric properties that are dependent on the water content of the matrix. At high water contents the elastic modulus is less than that of wet native aortic elastin and becomes greater on drying.

Cross-linked polypentapeptide of tropoelastin: an insoluble, serum calcifiable matrix

The synthetic, cross-linked polypentapeptide of tropoelastin has been shown to calcify from serum alone even when separated from the serum medium by a dialysis membrane with a low-molecular-weight cut off. By microprobe analysis, it appeared that the only serum elements required for the calcification were calcium and phosphorus. Furthermore, thin sections of the calcified matrix showed the calcification to occur throughout the matrix, and thereby verified that it is a bulk property of the matrix and not an interfacial property. To our knowledge this is the first demonstration of an insoluble, synthetic polypeptide to function as a serum calcifiable matrix and by doing so it opens the door to potential medical applications.

Action of amino acids and convulsants on cerebellar spontaneous action potentials in vitro: effects of deprivation of C1-, K+ of Na+

(1) The inhibition of spontaneous action potentials in guinea pig cerebellar cortex slices by GABA, glycine, taurine and beta-alanine is maintained when C1- in the superfusion medium is almost completely replaced by NO3- or I-('permeant' anion), but the inhibition decreases in magnitude with repeated application of the amino acid. Replacement of C1- by sulfate or isethionate ('impermeant' anion) causes a conversion of inhibition by these amino acids to excitation. The initial excitation which is sometimes seen with these inhibitory amino acids in high C1- media is abolished when C1- is replaced by either permeant or impermeant anions. (2) Reduction of K+ in the medium causes an increase of inhibition by the inhibitory amino acids in the presence of high C1- and reduction of excitation when C1- is replaced by impermeant anion. (3) Excitation by GABA in impermeant anion (low C1-) media is unaffected by reduction of Na+ in the media by 50% but excitations by glycine, taurine, beta-alanine and L-glutamate are greatly reduced. (4). Excitation by GABA in impermeant anion (low C1-) media is abolished by picrotoxin and bicuculline which both suppress inhibition by GABA in a high C1- medium. Strychnine suppresses the effects of glycine, taurine and beta-alanine in either a low or high C1- medium. Bicuculline blocks the inhibitory effect of these three amino acids in a high C1- medium but does not affect their excitatory effects in a low C1- medium. (5) These results are consistent with the hypothesis that the inhibitory amino acids, GABA, glycine, taurine and beta-alanine, cause inhibition via increase of C1- (and perhaps K+) permeability and that glycine, taurine and beta-alanine also interact with strychnine-sensitive receptors mediating (perhaps indirectly) increased permeability to Na+ and, therefore, excitation in low C1- media.

Genetic predisposition to stroke in spontaneously hypertensive rats

Hypertension and stroke in spontaneously hypertensive rats (SHR) were investigated genetically using stroke-prone SHR (A3), stroke-resistant SHR (C) and their hybrids, hybrid of A3 and C (F1), offspring of F1 X F1 (F2), and those of backcrossing of F1 to the respective parental strains, BC(F1 X A3) and BC(F1 X C). The average blood pressure measured without anesthesia increased in the following order during the experimental period: C less than BC (F1 X C) less than F1 approximately F2 less than BC(F1 X A3) less than A3. The F2 represented a wider spread of variation than the F1, with some of the pressure extending into the range of both parental strains. When the drinking water was replaced with a 1% salt solution, the blood pressure increased and the onset of stroke markedly accelerated in all groups of SHR. Under the hypertensive conditions, the incidence of stroke was associated with A3-gene concentration rather than with the level of blood pressure. Similar but less dramatic effects of salt were observed in another series of hybrid groups derived from A3 and normal Wistar-Kyoto rats. These findings suggest that the genetic factors are of great importance in the development of stroke as well as hypertension in the SHR.

Effects of amino acids and convulsants on spontaneous action potentials in cerebellar cortex slices

1 Picrotoxin selectively and reversibly suppressed the inhibitory action of gamma-aminobutyric acid (GABA), but not that of glycine, taurine or beta-alanine, on the frequency of spontaneous spike discharges in guinea-pig cerebellar slices. Strychnine reversibly suppressed the inhibitory action of glycine, taurine or beta-alanine but had no effect on that of GABA. 2 GABA, glycine, taurine and beta-alanine showed an early excitatory effect that was unaffected by picrotoxin or strychnine. 3 Studies of the dose-response relations indicated a competition between the amino acid and the convulsant at a common receptor site. 4 Kinetic analyses of the dose-response relations for the amino acids in the presence or absence of picrotoxin or strychnine indicated that the number of molecules of amino acid combining with the receptor site in order to produce a response (inhibition or excitation) was 3 for GABA, 2 for glycine, 3 for taurine and 4 for beta-alanine. There appeared to be no evidence that the response was due to the cooperativity between the amino acid receptor complexes. The number of molecules of convulsant that combined with the receptor site was 1 for either strychnine or picrotoxin. 5 Mixtures of glycine with taurine or beta-alanine, in contrast to those with GABA, appeared not to give additive inhibitory effects.

Recovery of the accumulation ability of thiomethyl-beta-galactoside in Escherichia coli after bacteriophage T4 infection

Effects of UV-irridiated and unirradiated T4 phage infection on the beta-galactoside accumulation ability in Eschericia coli have been examined by the use of 14C-labeled thiomethyl-beta-galactoside (TMG). Under conditions where a synchronous adsorption of phage takes place, the cellular ability for TMG accumulation is found to be largely inhibited immediately after phage adsorption, but it recovers with time to a new level, which is dependent on the multiplicity of infection. When cells are infected with UV-irradiated T4 at the same multiplicity as that of unirradiated phage, the cellular accumulation ability is more severely inhibited and there is no recovery from the inhibition. The recovery process in T4-infected cells is mostly sensitive to puromycin. These results suggest that the initial inhibition of the TMG accumulation ability is probably caused by the adsorption of phage coats, and the subsequent restoration occurs through the action of a phage-directed protein(s). In the recovery process, no new transport system appears to be involved. The restored ability of TMG accumulation is resistant to the action of superinfecting UV phage. However, different mechanisms appear to be operating in T4-infected cells for the establishment of resistance to ghosts and for the recovery from the phage coat-induced inhibition.

[Clinical study of amoxicillin used in the otorhinolaryngological field (author's transl)]

The following results were obtained from oral administration of amoxicillin to 20 cases of acute otorhinolaryngological infections for 5 consecutive days; the daily dose was 1,500 mg for adult and 750mg for child. 1. Six cases with acute tonsillitis, 6 with acute pharyngolaryngitis, 5 with acute otitis media, 2 with furuncle of the nose and 1 with acute laryngitis were treated with amoxicillin. This drug was remarkably effective in 2 of 20 cases in total, effective in 15, slightly effective in 1 and non-effective in 2. 2. The sensitivity test to amoxicillin by the use of ampicillin sensitivity disk revealed that all of isolated bacteria were remarkably sensitive to amoxicillin, except one strain of Staphylococcus aureus which was moderately sensitive. 3. Side effect occurred at the rate of 25%; 4 cases of eruption and 1 of esophagitis. Other severe side effects were not observed. From the above results, amoxicillin is considered to be an effective drug for clinical application in the otorhinolaryngological field.

A lack of inhibitory action of bacteriophage T4 ghosts in the presence of EDTA

Adsorption of bacteriophage T4 ghosts on to Escherichia coli cells has been known to cause a dramatic change in the cellular metabolism, the effect being similar to that of colicin K. It is shown here that the inhibitory activity of ghosts is not expressed either at 0 degrees C in the ordinary media (like colicin K) or even at 30 degrees C in a medium containing EDTA, in contrast to colicin K. Since the process of sheath contraction of T4 phage is blocked by EDTA, it is suggested that the adsorbed ghosts may not exert their inhibitory activity until sheath extraction occurs.