Thermodynamics of polyol-induced thermal stabilization of chymotrypsinogen

In order to clarify the mechanism of polyol-induced stabilization of protein, the thermodynamic parameters (delta G degree, delta H degree, and delta S degree) of thermal denaturation of chymotrypsinogen have been measured in aqeous solutions of some polyols (ethylene glycol, erythritol, adonitol, sorbitol, mannitol, and inositol) by a differential spectrophotometric method. On increasing the alcohol concentration and the number of hydroxymethyl groups of the alcohols, delta G degree increased as a result of a large decrease in delta S degree compensating for a decrease in delta H degree. This result means that the stabilization of this protein by polyols is due to the entropy effect, and that the free energy change of transfer of the denatured protein from water to aqueous media containing these alcohols must be larger than that of the native protein. This strongly supports the previous proposal that the driving force of protein stabilization induced by polyols is a solvent medium effect or a solvent ordering effect. The decreases in delta H degree and delta S degree with polyols are expected to be more due to the effects of polyols on peptide-water interactions than to exposed nonpolar groups of denatured protein.

Cladded radially inhomogeneous sphere lenses

When a radially inhomogeneous sphere is cladded with an additional refractive-index medium, the spherical transverse aberration of a resultant lens is minimized in order to image a point light source in the diffraction-limited spot size for a lens a few millimeters in diameter with ~0.4 N.A. Examples of numerical data used in designing such sphere lenses are given for three different cases: imaging, Fourier transform, and optical disk reading. Various uses of these lenses are also envisioned for demonstrating their potential usefulness.

Spectroscopic small loss measurements on infrared transparent materials

Small losses of NaCl, KBr, TICI, KRS-5, CsI, and PbI(2) near 10 microm were measured using an improved differential infrared spectrophotometer with an accuracy better than 0.1% in transmittance. TlCl shows relatively large intrinsic multiphonon absorption, whereas the others show only impurity loss. PbI(2), with the possibility of glass formation, shows its infrared absorption proportional to exp(-omega/37.5), where omega is the frequency in cm(-1).

Inhibitors of procollagen N-protease. Synthetic peptides with sequences similar to the cleavage site in the pro alpha 1(I) chain

A series of peptides was synthesized with amino acid sequences identical with the cleavage site at which the procollagen N-protease cleaves the N-terminal propeptide from the pro alpha 1 chain of type I procollagen. Peptides up to 11 residues in length did not serve as substrates for the enzyme, an observation consistent with the demonstration that the N-protease will not cleave denatured procollagen or dissociated pro alpha chains. Several of the peptides, however, served as effective inhibitors of the cleavage of procollagen. Comparison of the inhibitor activities of peptides of varying lengths suggested that the L-phenylalanine found three residues to the left of the cleavage site was important for inhibitor activity. This suggestion was confirmed by synthesis of analogues of inhibitory peptides in which L-phenylalanine was replaced by D-phenylalanine, tyrosine, lysine, aspartic acid, or glycine.

Analytic study of epileptic absence seizures and effect of sodium valproate treatment

Two hundred and seventy eight absence seizures were recorded from 60 patients by an intensive monitoring device. They were divided into two subtypes, typical and atypical absences based on their ictal discharges whether the spike-wave rhythm was at 3 cps or not. These two absence seizures did not differ so much with regard to loss of consciousness except that: 1) the durations of discharge in atypical absences were longer than those of typical ones, 2) the recovery from clouded consciousness to a state of full-awareness was apparently delayed in atypical absences after the termination of epileptic discharges, 3) the oral automatisms were more associated with typical absences and the decreased postural tones with atypical absences. By a numerical analysis of two parameters of spike-wave, that is, its frequency ad rhythmicity, it was shown that absences with spike-waves slower than 30 cps and with poor rhythmicity which roughly corresponded with atypical absences were more therapy-resistant in comparison with those having 3 cps spike waves and good rhythm which were usually typical absences. Sodium valproate was more effective on typical absences, however, there was no difference between typical and atypical absences in the therapeutic maintenance concentrations of serum valproate acid. We would like to emphasize that the comparison of the symptomatology between typical and atypical absences is of significance not only for understanding the etiology of the epilepsies but for the guideline of practical pharmacotherapy.

Status epilepticus in childhood: a retrospective study of initial convulsive status and subsequent epilepsies

A retrospective study was carried out on 261 patients with various epilepsies who had undergone convulsive status epilepticus prior to the subsequent onset of epileptic seizures. 1. Convulsive status epilepticus was found more in partial epilepsy and secondary generalized epilepsy at about the same rate, and evidently less in primary generalized epilepsy. On the average, three-fourths commenced their convulsive disorders with initial status epilepticus. 2. There were free intervals of years following initial status and preceding subsequent epilepsy. The interval was evidently shorter, less than two years, in a majority of patients with secondary generalized epilepsy, whereas the interval was mostly longer, more than six years, in patients with partial epilepsy. 3. The permanent deficient sequelae resulting from initial status were most closely associated with secondary generalized epilepsy. This was also exemplified by the higher rate of atrophic change on CCT. On the contrary, such permanent sequelae were less marked in partial epilepsy especially of complex seizure. 4. It was concluded that secondary generalized epilepsy resulted in cases with more severe brain damage within a relatively shorter interval, whereas complex partial seizure resulted from less severe damage with an obviously longer interval following convulsive status epilepticus.

Conformational studies of oxytocin analogues with different ring sizes. I. Circular dichroism

Circular dichroic spectra were measured for three analogues of deamino-oxytocin of different ring sizes where the disulfide group of oxytocin is replaced by the (CH2)n group. Their backbone rings are composed of different numbers of atoms, i.e., they are nineteen, twenty and twenty-one for [1,6-aminopimelic acid]oxytocin (n = 1), [1,6-aminosuberic acid]oxytocin (n = 2) and [1,6-aminoazelaic acid]oxytocin (n = 3), respectively. The pH dependence of the circular dichroism spectra indicates that the conformation of [1,6-aminoazelaic acid]oxytocin is different from those of others and the temperature dependency reveals that the conformation of [1,6-aminopimelic acid]oxytocin is most rigid. [1,6-Aminosuberic acid]oxytocin is biologically most active among three derivatives and their biological activities are related to the conformation and internal motions of the peptide hormone analogues.

Practical improvements of writing and reading algorithm in computer-generated polarization holography

This paper reports on a newly developed algorithm for improving the previously reported basic theory of computer-generated polarization holography. An application of the algorithm to the basic theory shortens the hologram making time, which uses a limited quantity energy of an illuminating uv spot light. A relation between a polarization angle of the illuminating uv beam and an effective amplitude transmittance Tp of a crystal-analyzer pair is derived. Furthermore, a method for correcting an effect of the pre-existing unbalance of the degree of the density balance of M-centers in a binary state is proposed. Also, the theory of the method is theoretically discussed in detail together with a derivation of the theta vs Tp curves characteristic of this case.

A retrospective study on the prognosis of aged patients with epilepsy

A retrospective follow-up study on the prognosis of 90 patients with epilepsy above 40 years of age has resulted in: 1. In the aged patients, the duration of epilepsy (mean: 23 years) was longer than the period of treatment they underwent (mean: 14 years). The delayed commencement and/or interrupted medication along with the patients' incompliance of taking drugs accounted for the main reasons for at least 70% of the patients. 2. The partial epilepsy (80%) especially with complex symptomatology (55%) were predominating in the aged group. And also, that the tonic-clonic seizures were liable to convert to the complex partial seizures in their thirties and forties, was found in this study. 3. Although almost all the patients (97%) had more or less clinical attacks even at the time of survey, 75% or more decrease in seizure frequency have been exerted for one and a half year, regardless of the seizure types in the majority of the patients (81%). This seems to offer an explanation that an appropriate sociomedical strategy is necessitated for patients with long-standing epilepsies.

Electrically accessible Lippmann hologram memory

Using Fe-doped LiNbO(3) crystals we have constructed Lippmann-type holograms where access both in writing and in reading is performed electrically. Discussions are given for the interlayer cross talks in a stacked structure. Device operations are demonstrated with a double-layered memory.

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.

Synthesis of eel-calcitonin and (asu1,7)-eel-calcitonin: contribution of the disulfide bond to the hormonal activity

Eel-calcitonin and its [asu1,7]-analog, deamino-dicarba-analog, were synthesized by the conventional solution method. The natural-type product showed 4300 MRC U/mg in the hypocalcemic potency which was comparable to that of the natural hormone isolated from eel. Hormonal activity of the Asu-analog was also as high as 3400 MRC U/mg.