In-plane and out-of-plane ferroelectric instabilities in epitaxial SrTiO3 films.

The in-plane and out-of-plane ferroelectric instabilities in compressed (100)-epitaxial SrTiO3 films were examined by infrared reflection spectroscopy. The strongly stiffened in-plane soft mode frequency softened very slowly on cooling. On the other hand, the silent mode appeared at around 150 K, indicating an out-of-plane ferroelectric transition. This behavior points to a split of in-plane and out-of-plane ferroelectric instability temperatures due to the lowered symmetry of the SrTiO3 lattice caused by mechanical misfit strain. Infrared spectroscopy provides a possibility to detect such an effect in the strained epitaxial ferroelectric films.

Protein binding and the metabolism of thiamylal enantiomers in vitro.

UNLABELLED: Thiamylal, a chiral thiobarbiturate, is marketed as a racemic product. We studied the serum protein binding and microsomal metabolism of thiamylal enantiomers in vitro. The unbound fraction of R(+)-thiamylal was greater than that of S(-)-thiamylal. The analysis of binding data revealed that both enantiomers bound to human serum albumin through only one site. In displacement studies with site-specific probes, dansylsarcosine, but not warfarin, significantly decreased the binding of both enantiomers. The bindings of enantiomers were also decreased by octanoate and a large concentration of oleate. These findings suggest that both enantiomers bind to Site II of albumin with higher affinity for S(-)-enantiomer. R(+)-thiamylal was metabolized more rapidly than S(-)-enantiomer by human liver microsomes. An experiment with isoform-selective inhibitors and cytochrome P-450 (CYP) isoforms showed that CYP2C9 had the highest activity for the metabolism of both enantiomers, the activity being 7 to 10 times that of CYP2E1 and CYP3A4. CYP2C9 showed a significantly rapid metabolism of R(+)-enantiomer, suggesting that CYP2C9 is mainly involved in the enantioselective metabolism of thiamylal. IMPLICATIONS: Because clinically marketed thiamylal is a racemic compound, a pharmacokinetic study of each enantiomer may be beneficial. We found that the enantioselectivity of thiamylal existed in protein binding and metabolism. This may be caused by the differences in the affinities of enantiomers for albumin and cytochrome P-450 isoform.

Improved method of determining thiamylal enantiomers in human serum by high-performance liquid chromatography.

Thiamylal, a widely used anesthetic drug, has two enantiomers. We developed a simple and rapid method for measuring the thiamylal enantiomers in human serum. The method involves a liquid-liquid extraction procedure followed by chiral resolution using a 5 microm silica-bonded alpha1-acid glycoprotein column (Chiral-AGP). The thiamylal enantiomers and internal standard were eluted within 15 min and were well-resolved. At concentrations of 1, 5 and 20 microg ml(-1), the relative standard deviations of R(+)- and S(-)-thiamylal were 1.35-2.88% and 1.37-3.01%, respectively, for the intra-day assay, and 2.93-4.46% and 2.46-4.84%, respectively, for the inter-day assay. This method facilitates the routine monitoring and pharmacokinetic studies of thiamylal enantiomers.

Erythrocyte sodium ion transport system in DOC-salt, Goldblatt, and spontaneously hypertensive rats.

Altered erythrocyte Na+ transport has been observed in relation to the pathogenesis of essential hypertension. In the present study, intracellular Na+ and K+ levels, Na(+)-K+ pump activity, Na(+)-K+ cotransport, and Na+ passive permeability were measured in erythrocytes of DOC-salt hypertensive (DSH) rats, two-kidney, one clip Goldblatt hypertensive (2KH) rats, and spontaneously hypertensive rats (SHR). The results were as follows: 1. In comparison with the control groups, no change in the erythrocyte Na+ level was noted in the DSH and 2KH groups, whereas a significant increase was seen in the SHR group. 2. Although no change was noted in the erythrocyte K+ level in the 2KH and SHR groups when compared with the control groups, a significant decrease was seen in the DSH group. 3. Na(+)-K+ pump activity of erythrocytes was not changed in the DSH and 2KH groups when compared with the control group, but a significant increase was noted in the SHR group. 4. Na(+)-K+ cotransport of erythrocytes was not changed in any hypertensive rats when compared with the controls. 5. Na+ passive permeability in the erythrocyte membrane was not changed in the DSH and 2KH groups when compared with the control groups, but a significant increase was noted in the SHR group. These findings suggest that increased erythrocyte Na+ levels in SHR are due to increased Na+ passive permeability of the erythrocyte membrane, and increased Na(+)-K+ pump activity may be compensating for the increased intracellular Na+ concentration in erythrocytes. Furthermore, the increase in Na+ passive permeability observed in SHR might not result from hypertension itself but from abnormalities in the erythrocyte cell membrane, because no increase in Na+ passive permeability was noted in either DSH or 2KH rats.

Acute effects of angiotensin-converting enzyme inhibitor on erythrocyte sodium ion transport in essential hypertension.

The acute effects of angiotensin-converting enzyme inhibitor, captopril, on sodium ion transport systems were investigated in essential hypertensive and normotensive subjects. The passive sodium efflux through the erythrocyte membrane was significantly higher and erythrocyte sodium-potassium cotransport was lower in patients with essential hypertension when compared with normal subjects. However, sodium-potassium pump activity and sodium-lithium countertransport did not differ significantly between the hypertensive patients and the normal subjects. Immediately after captopril administration, erythrocyte passive sodium efflux and sodium-potassium cotransport returned to normal levels in the hypertensive subjects. Although the plasma renin activity and plasma aldosterone concentration were altered by captopril, they did not correlate with changes in any sodium transport system. These results suggest that the changes in sodium transport systems which occur immediately after captopril administration may contribute, at least in part, to its antihypertensive action.

Influence of the mother-child relationship on the development of the Type A behavior pattern.

Investigation of the Type A Behavior Pattern (TABP) of pre-school children was conducted to determine the influence of the mother-child relationship on the development of TABP. The incidence of TABP was 44.2% (51.7% in boys and 38.7% in girls). The TABP tendency of the boys decreased as the manifest dissension or conflict in the family grew, in marked contrast with the tendency seen in girls, suggesting that conflict in the family can either weaken or reinforce TABP.

Effects of dietary Ca2+ on erythrocyte Na(+)-transport systems in spontaneously hypertensive rats.

1. The purpose of this study was to determine the effect of dietary Ca2+ intake on blood pressure and erythrocyte Na+ transport in spontaneously hypertensive rats. 2. Spontaneously hypertensive rats and Wistar-Kyoto rats were fed diets with three different Ca2+ contents, 0.1% (low-Ca2+ diet), 0.6% (normal-Ca2+ diet) and 4.0% (high-Ca2+ diet), between 6 and 20 weeks of age. At 20 weeks of age, the levels of erythrocyte Na+ efflux, as well as Na+ and K+ contents in erythrocytes, were measured. 3. On the low-Ca2+ diet, spontaneously hypertensive rats showed an enhancement of hypertension. Conversely, on the high-Ca2+ diet, they showed an attenuation of the increase in blood pressure. Spontaneously hypertensive rats had a lower erythrocyte Na+ content and increased activity of the Na+ pump at higher levels of dietary Ca2+. Passive Na+ permeability and Na(+)-K+ co-transport were similar in spontaneously hypertensive rats on the low-, normal- and high-Ca2+ diets. There were no significant differences in blood pressure and in Na+ pump activity in WKY on the three different diets. 4. It is concluded that dietary Ca2+ might affect the regulation of blood pressure in spontaneously hypertensive rats by changing the activity of Na+ pump in the cell membrane.

Effects of dietary calcium on erythrocyte sodium ion transport systems in spontaneously hypertensive rats.

The alteration of sodium ion transport in red blood cells was observed in SHR and patients with essential hypertension. The purpose of the present study was to determine the effects of dietary calcium intake on blood pressure and sodium ion transport of red blood cells in SHR. The SHR were fed a diet with three different levels of calcium contents as follows: 0.1% (low), 0.6% (normal) and 4.0% (high) of calcium between 6 and 20 weeks of age. At 20 weeks of age, the levels of erythrocyte sodium efflux, sodium or potassium contents in the red blood cells were measured. On the high Ca diet, SHR showed an attenuation of the increase in blood pressure. On the low Ca diet, SHR showed an enhancement of hypertension. In proportion of increasing of dietary calcium contents, SHR had a lower level of sodium content in the RBC and a higher activity of the sodium pump. However, the passive sodium permeability and sodium-potassium cotransport in SHR were similar among the three different Ca diets. It is concluded that the amounts of dietary Ca might be related to the regulation of blood pressure by changing the sodium pump of the cell membrane in SHR.

[Effect of dietary calcium on erythrocyte sodium pump in spontaneously hypertensive rats (SHR)].

The purpose of the study was to determine the effect of dietary calcium intake on blood pressure and sodium ion transport of red blood cells (RBC) in spontaneously hypertensive rats (SHR). The SHR were fed by diet with three different levels of calcium contents as follows; 0.1% of Ca (low Ca diet), 0.6% of Ca (normal Ca diet) and 4.0% of Ca (high Ca diet) between 6 and 20 weeks of age. At 20 weeks of age, the levels of erythrocyte sodium efflux, as well as sodium and potassium contents in the RBC were measured. On the low calcium diet, SHR showed an enhancement of hypertension. On the high calcium diet, SHR showed an attenuation of the increase in blood pressure. In proportion to the levels of dietary calcium contents, SHR had a lower level of sodium contents in the RBC and a higher activity of the sodium pump. The passive sodium permeability and sodium-potassium cotransport in SHR were similar among low, normal and high calcium diet groups. It is concluded that the amounts of dietary calcium might be related to the regulation of blood pressure by changing the sodium pump of the cell membrane in SHR.

A case of massive ascites due to lupus peritonitis with a dramatic response to steroid pulse therapy.

A 52-year-old female patient with massive ascites due to lupus peritonitis is described. Skin biopsy specimens revealed typical features of systemic lupus erythematosus (SLE) in light microscopic and immunofluorescent examinations. Immune-complexes, antinuclear antibody and hypo-complementemia were detected in the peritoneal fluid. The massive ascites responded dramatically to steroid pulse therapy. The levels of circulating immune-complexes, anti-nuclear antibody and complement in sera were also improved after such therapy. It was suggested that steroid pulse therapy may be useful for massive ascites due to lupus peritonitis.

Holographic memory system for Kanji character generation.

A Fourier transform holographic memory has been developed and used for generating and storing sixteen thousand Kanji characters. The memory consists of four groups of holograms of 63 pages, recording 64 Kanji characters in each page, and has a packing density of 1.34 x 10(7) bits/cm (2). Digitized characters of sixteen sizes can be generated with natural letter faces and good image quality. This paper focuses on the recording and reconstruction of holographic Kanji memory using a pseudorandom diffuser and systematic solutions consistent with optical, mechanical, and digital systems.