Islet amyloid polypeptide amide causes peripheral insulin resistance in vivo in dogs

Islet amyloid polypeptide is a 37 amino acid hormone-like peptide which is the major protein component of islet amyloid deposits commonly found in patients with Type 2 (non-insulin-dependent) diabetes mellitus. Recent studies indicate that a physiologically active form of this peptide appears to be carboxyamidated and secreted from the insulin-producing beta cell. In order to clarify the possible in vivo actions of islet amyloid polypeptide, we have studied the effects of synthesized islet amyloid polypeptide-amide on peripheral glucose utilization by performing hyperinsulinaemic euglycaemic glucose clamp studies on dogs. Exogenously administered islet amyloid polypeptide-amide (an infusion from 1.0 to 100 micrograms.kg-1.h-1, over 2 h) inhibited the insulin-stimulated glucose disposal rate in a dose dependent manner. Twenty-five micrograms.kg-1.h-1 of islet amyloid polypeptide-amide infused via a peripheral vein significantly lowered the glucose disposal rate by 20% (from 17.4 +/- 1.7 to 14.4 +/- 1.7 mg.kg-1.min-1, n = 5, p less than 0.01). These findings suggest that islet amyloid polypeptide-amide causes peripheral insulin resistance in vivo.

[Direct evidence of alpha-adrenoceptor binding in rat and human adrenal glands]

In order to determine whether or not alpha-adrenoceptors are present in adrenal glands, radioligand receptor binding assay was performed in both Sprague-Dawley (SD) rat and human adrenal gland membranes. Radioligand binding assay using 3H-prazosin as an alpha 1-adrenoceptor ligand and 3H-yohimbine as an alpha 2-adrenoceptor ligand, clearly demonstrated alpha 1 and alpha 2 receptors present in both rat and human adrenal gland membranes. Maximal binding capacity (Bmax) and dissociation constant (Kd) of 3H-prazosin binding to the rat adrenal gland were 12.5 fmol/mg protein, and 0.11 nM, respectively. Those for the membrane preparations from adrenal cortex and medulla of the normal human were 16.3 fmol/mg protein, 0.34 nM and 16.3 fmol/mg protein, 0.27 nM, respectively. And those of the human pheochromocytoma were 25.6 fmol/mg protein, 0.15 nM, respectively. On the other hand, Bmax and Kd of 3H-yohimbine binding in the rat adrenal gland to were 22.9 fmol/mg protein, and 4.28 nM, respectively. Those for the membrane preparations from adrenal cortex and medulla of the normal human were 40.4 fmol/mg protein, 5.15 nM and 12.2 fmol/mg protein, 5.39 nM, respectively. And those of the human pheochromocytoma were 35.8 fmol/mg protein, and 1.08 nM, respectively. Bmax (35.8 fmol/mg protein) of 3H-yohimbine binding in the pheochromocytoma was significantly (p less than 0.01) greater than that (12.2 fmol/mg protein) in the human normal adrenal medulla, while Kd (1.08 nM) of this binding in the human pheochromocytoma was significantly (p less than 0.01) lower than that (5.39 nM) in the human normal adrenal medulla. Our data suggest that the alpha 2 receptor had greater affinity and binding site density to its agonist in the human pheochromocytoma than in the human normal adrenal medulla.

Effects of mianserin on human sleep

Sleep EEG and nocturnal penile tumescence (NPT) were investigated in 6 healthy men during placebo and mianserin administration and after mianserin withdrawal. The results were assessed in a historical comparison with those previously obtained with clomipramine. With mianserin, REM sleep was suppressed slightly. However, the suppressive effect of mianserin on REM sleep--based on the historical comparison--was significantly weaker than that of clomipramine throughout all the drug nights. Accordingly, a rebound increase in REM sleep was not observed after withdrawal. Less suppressive effects on NPT and disturbance of sexual function with mianserin than with clomipramine were observed. We suggest that a correlation between the prolonging effect on REM latency and the clinical antidepressant effect is limited to some antidepressants.

Plasma concentration of atrial natriuretic factor in idiopathic oedema

Low level of plasma atrial natriuretic factor (ANF) under altered dietary sodium and its elevation during bigeminy were found in a 40-year-old woman with idiopathic oedema. The natriuretic effect of this peptide and the role of renin-angiotensin-aldosterone system in oedema formation in this disorder are discussed.

[Study of the effects of dopamine hydrochloride on alpha 1-adrenoceptors in rat kidney]

We studied the number and affinity of catecholamine receptors in SD rat kidney by radioreceptor technique. The following conclusions were obtained: 1) By using 3H-prazosin, the numbers of alpha 1-receptor (Bmax) in rat renal cortex were greater than those in rat kidney medulla. As for affinity (Kd), the significance was not recognized between the two. Bmax of the rat renal cortex to 3H-prazosin binding was 96.1 fmol/mg protein, and Kd was 0.17 nM, and for the rat renal medullar these values were 44.5 fmol/mg protein and 0.13 nM, respectively. 2) By measurement of D1-receptor using 3H-SKF38393 in the rat renal cortex in the Scatchard plot analysis, positive cooperativity was observed under the low concentration of hot ligand which was less than 1 nM. But at the concentration of hot ligand over 1 nM, the plots showed a straight line. Bmax of the rat renal cortex to 3H-SKF38393 was 2.5 pmol/mg protein and Kd was 5.3 nM. 3) Based on displacement by dopamine for 3H-prazosin binding to rat renal cortex, it was surmised that high concentration of dopamine had an affinity to alpha 1-adrenoceptors. 4) There was no change in the Kd and Bmax of alpha 1-receptor in the rat renal cortex after incubation of samples with low concentration of dopamine. However, in the case of high concentration of dopamine, a remarkable decrease of the affinity (Kd) of alpha 1-adrenoceptor was observed.

Evaluations of frequency shift and stability in rubidium vapor stabilized semiconductor lasers

Laser frequencies were stabilized to the linear and saturated absorption spectral lines(LAS, SAS) in (87)Rb vapors which were filled into two kinds of glass cell: cell A ((87)Rb vapor only) and cell B ((87)Rb vapor and buffer gases). The frequency shifts induced by the change of laser power density were -5 MHz/(mW/cm(2)) and - 10 MHz/(mW/cm(2)) for cells A and B, respectively, when LAS was used. A frequency shift of -0.8 MHz/K was observed for cell B, which underwent a temperature change. However, such a temperature-induced shift was not observed for cell A. The highest frequency stability was 7.7 x 10(-11) at a 70-s integration time.

The effect of adrenal surgery on plasma atrial natriuretic factor and sodium escape phenomenon in patients with primary aldosteronism

Plasma concentrations of atrial natriuretic factor and some vasoactive substances were determined in 8 patients with aldosterone-producing adenoma, 10 with idiopathic adrenal hyperplasia, 10 normotensive subjects and 12 patients with essential hypertension. Plasma atrial natriuretic factor concentration in patients with aldosterone-producing adenoma was the highest among the examined groups. Adrenal surgery reduced plasma concentrations of atrial natriuretic factor and aldosterone concomitant with the elevation in urinary sodium excretion, plasma renin activity and urinary sodium-to-potassium ratio. Withdrawal of trilostane (3 beta-hydroxysteroid dehydrogenase inhibitor) in patients with idiopathic adrenal hyperplasia increased plasma concentrations of atrial natriuretic factor and aldosterone, and decreased the urinary sodium-to-potassium ratio, plasma renin activity and urinary sodium excretion. However, reduced urinary sodium excretion following trilostane treatment returned to the control level successively despite the high levels of plasma atrial natriuretic factor and aldosterone. Acute infusion of saline remarkably increased plasma atrial natriuretic factor concentration in patients with idiopathic adrenal hyperplasia and aldosterone-producing adenoma. These results suggest that a high level of atrial natriuretic factor is a characteristic feature in patients with aldosterone-producing adenoma caused chiefly by the expansion of extracellular fluid volume, and circulating atrial natriuretic factor may contribute to regulation of the sodium escape phenomenon in patients with aldosterone-producing adenoma or idiopathic adrenal hyperplasia.

Age-related differences in norepinephrine and non-collagenous protein in human vas deferens

The existence of norepinephrine or non-collagenous protein in some tissues is believed to reflect the sympathetic discharge of the structures and plays an important role in contractile ability. Specimens of vas deferens were obtained from 44 subjects in various decades of life from age 20 to 84, and levels of norepinephrine, non-collagenous protein, collagen and elastin were determined. The level of norepinephrine and non-collagenous protein declined with increasing age. Both parameters inversely correlated with age. Collagen and elastin increased with advancing age. The regression line and coefficient of correlation between both variables showed significantly positive correlations. It is suggested that the contractile ability of human vas deferens, as defined by norepinephrine and non-collagenous protein contents, decreases with age, and the age-related increase in collagen and elastin may be of importance in reducing the contractile capability of this structure.

Impaired urine concentrating ability in Itai-itai (ouch-ouch) disease

A case of Itai-itai (ouch-ouch) disease with reduced urinary kallikrein excretion and slightly enhanced renin-angiotensin-aldosterone system is described. Although it is well known that cadmium toxicity frequently affects the renal tubular lesions, this report is the first to demonstrate the impaired urine concentrating ability in this disease.

Effect of hyperbaric oxygen therapy on essential haematuria

Forty-three patients with essential haematuria were studied for 35 days to determine the efficacy of hyperbaric oxygen (OHP) exposure on haemostatic ability. Out of 15 untreated patients, haematuria persisted for the study period in all but one patient (6.7%). Out of 11 patients who received 90 mg/day of carbazochrome sodium sulfate and 750 mg/day of tranexanic acid excellent haemostatic results had been obtained in 2 (18.2%). Results of exposure of 17 patients to 2 atm. pressure of OHP for 90 min daily were excellent in 10 (58.8%) and good in one (5.9%). No serious adverse effects had been noted following OHP treatment. These results indicate that OHP can be applied for the treatment of essential haematuria if routine haemostatic drugs fail to improve the condition.

[Two cases of pathological dilatation of seminal duct end]

Two cases of male infertility due to pathological dilatation of seminal duct end are reported. One patient was 33 years old. He was diagnosed with azoospermia by semen analysis. The cystic wall of the seminal duct end was incised by a cold knife on the urethral scope. After the operation, 100,000-500,000/ml sperms were found in his semen. The other patient was 31 years old. He was diagnosed with severe oligoasthenozoospermia. He was operated on in a similar operation. After operation, the findings of his semen analysis improved exceedingly, and his wife became pregnant.

Stimulation of guinea pig neutrophil superoxide anion-producing system with thymol

Thymol stimulated O2- production in guinea pig neutrophils. O2- production occurred about 30 sec after the addition of thymol, and its rate was independent of extracellular Ca2+. Thymol-induced activity was inhibited by trifluoperazine (TFP), an inhibitor of protein kinase c, and its IC50 was less than that for 12-O-tetradecanoyl phorbol 13-acetate (TPA) induced activity. After complete activation, O2- production was reversed by addition of TFP or by washing out and resuspending in a stimuli-free medium. The responsiveness of the thymol-pulsed cells to another stimulus, TPA, was somewhat more than resting cells, but the responsiveness of the former cells to thymol was about half that of the latter cells. The ATP level of cells was reduced to one half its initial value during activation by thymol. These data suggest that the magnitude of thymol-induced O2- production in neutrophils is dependent on the initial density of the binding sites of the cells with thymol and the initial intracellular ATP concentration.

Catecholamine metabolism in pheochromocytoma and normal adrenal medullae

The tissue contents of catecholamine, its precursor and its major metabolites were determined in 8 human pheochromocytomas and 26 normal adrenal glands. Pheochromocytomas contained significantly larger amounts of norepinephrine, dopamine, dihydroxyphenylalanine, tyrosine hydroxylase activity, metanephrine, normetanephrine and vanillylmandelic acid than did normal adrenal medullae. The content ratio of epinephrine/norepinephrine in normal adrenal medullae was significantly higher than that in pheochromocytomas but there were considerable individual variations in the metanephrine/normetanephrine and vanillylmandelic acid/3-methoxy-4-hydroxyphenylethylglycol ratios in pheochromocytomas. In normal adrenal medullae the tissue content of tyrosine hydroxylase activity correlated inversely with the tissue contents of epinephrine (r equals -0.78, p less than 0.001), norepinephrine (r equals -0.78, p less than 0.001) and total catecholamines (r equals -0.87, p less than 0.001), respectively but no significant relation was found between both parameters in pheochromocytomas. These results indicate the possible presence of a negative feedback mechanism of catecholamine via tyrosine hydroxylase in normal adrenal medullae but none in pheochromocytomas. In addition, the increased degradation catecholamine pathway in pheochromocytomas appears to be unstable compared to that in normal adrenal medullae.

Unilateral renal agenesis with or without ipsilateral adrenal agenesis

We analyzed 7 patients with unilateral renal agenesis. The coexistence of unilateral renal agenesis with ipsilateral adrenal agenesis was confirmed surgically in 2 patients, 1 of whom had clinical features of Cushing's syndrome owing to adrenocortical adenoma of a solitary adrenal gland. It is imperative to suspect abnormalities of the ipsilateral adrenal gland when unilateral renal agenesis is encountered. Unilateral renal agenesis usually is asymptomatic. Recognition of this anomaly is essential for early correct diagnosis.

[Renal cyst puncture under ultrasound guidance: complications of ethanol injection]

Under ultrasound guidance, we treated 25 cases of renal cyst with 99% ethanol instillation to prevent the recurrence of this disease from January 1985 to June 1987. Patients' age was from 17 to 85 years old with the average age of 63 years. Twelve cases were men, and 13 cases were women. Among the 25 cases, eleven were asymptomatic and 14 showed clinical features of lumbago, microhematuria, hypertension or proteinuria. The aspirated site was the right side in 9, left side in 14 and bilateral kidneys in 2 cases. Subsequently, cyst puncture was carried out 27 times. We encountered 12 complications following puncture. These complications were derived from the puncture itself or caused by the ethanol instillation. Flank pain caused by the injection of ethanol, nausea, causalgia or a feeling of drunkenness appeared immediately after the inoculation procedure. However, no serious complications such as pneumothorax, perirenal hematoma or infection were recognized. Some complications arose in 7 cases of 9 examples (77.8%) following more than 50 ml of ethanol injection, but the complications were observed in only 5 cases of 18 examples (22.8%) following less than 50 ml of administration. Based on these findings, ethanol injection in renal cysts appears to be useful for the treatment of this disease. In case of huge cysts when more than 50 ml of ethanol, is instilled the case should be followed up carefully after the instillation procedure.

Hyperplasia of juxtaglomerular cells and renomedullary interstitial cells after renal arterial embolization in patients with renal cell carcinoma

Renal tissue was obtained from 36 patients with renal cell carcinoma, some of whom received renal arterial embolization. The removed specimens was examined histopathologically and the concentration of some vasoactive substances in these patients was measured. Nephrectomy alone produced no discernible changes in blood pressure, vasoactive substances determined or histopathological findings of the kidney. Renal arterial embolization raised the blood pressure in association with the elevation of plasma renin activity (PRA) and urinary prostaglandin (PG) E2 excretion. A linear relationship was found to exist between PRA and mean blood pressure (r = 0.70, p less than 0.001). Hyperplasia of the juxtaglomerular (JG) apparatus, and high granularity of sudan black B granules in renomedullary interstitial cells were confirmed in removed kidneys of patients who had received embolization alone. Subsequently high renin production would be anticipated to influence overproduction of renal PG E2 in acute ischemic kidney in patients with renal cell carcinoma, and hypertension following renal arterial embolization appears to be caused by the hyperplasia of the JG apparatus.

Effect of high-calcium diet on urinary oxalate excretion in urinary stone formers

The effect of mild high-calcium diet or regular-calcium diet on urinary calcium excretion, urinary oxalate excretion, urinary calcium/creatinine ratio, urinary oxalate/creatinine ratio, and the probability of being a stone former (PSF) were studied in 85 patients with idiopathic urolithiasis. Intake of high-calcium diet for 5-6 days reduced (p less than 0.01-p less than 0.001) urinary oxalate excretion, urinary oxalate/creatine ratio and PSF in patients with idiopathic hypercalciuria. Under the regular-calcium diet, administration of 60 mg/day of pyridoxal phosphate for 3 months lowered (p less than 0.05-p less than 0.01) urinary oxalate excretion, urinary oxalate/creatinine ratio and PSF in patients with idiopathic hypercalciuria alone. From these findings, intake of mild high-calcium diet appears to be beneficial to decrease the urinary oxalate excretion and PSF in patients with idiopathic hypercalciuria. Pyridoxal phosphate has all the features of suppressing such risk factors for stone formation in patients with idiopathic hypercalciuria.

Differences of superoxide production in blood leukocytes stimulated with thymol between human and non-human primates

Thymol induced superoxide production (O2-) by blood leukocytes was examined in various primates including man. Leukocytes of chimpanzee and hamadryas baboon cells showed only 35% of the maximal O2- production rate obtained in human cells, and those of the Japanese monkey and orang-utan failed to respond. In contrast, when cells were stimulated with 12-O-tetradecanoyl phorbol acetate, no significant difference in the O2- production rate was observed between human and monkey cells except for chimpanzee. These results showed that human leukocytes are the most sensitive to thymol among the primates tested. The responsiveness of non-human primate leukocytes could be classified into two types, African-type(chimpanzee and baboon) and Asian-type(orang-utan and macaque).

Activation of the plasma kallikrein-kinin system by Vibrio vulnificus protease

Vibrio vulnificus protease enhanced hypodermic vascular permeability when injected into the dorsal skin of a guinea pig. Enhancement of permeability was observed within 2 min, and the permeability-enhancing reaction terminated at about 10 min postinjection. The permeability-enhancing reaction was greatly augmented by simultaneous injection of a kininase II inhibitor, whereas the reaction was inhibited by soybean trypsin inhibitor, a well-known inhibitor of plasma kallikrein. Furthermore, in vitro activation of plasma prekallikrein to kallikrein by V. vulnificus protease was observed. These results indicate that V. vulnificus protease enhances vascular permeability through activation of the plasma kallikrein-kinin system which generates bradykinin, factor in edema formation.

[Renal cell carcinoma incidentally found by computed tomography: report of 4 cases]

A clinical study was made on 26 patients with renal cell carcinoma, who visited our department between October, 1979 and April, 1984. There were 21 men and 5 women. As the major initial symptoms, hematuria and flank pain were observed in 14 cases (53.8%), followed by symptoms of metastatic tumors in 7 cases (26.9%). Four cases of malignant renal masses which showed no abnormality on the excretory urogram were diagnosed by chance at the time of examination of the abdominal computed tomography (CT). CT was especially useful in diagnosing the renal cell carcinomas.

Eugenol-mediated superoxide generation and cytotoxicity in guinea pig neutrophils

Eugenol is the medicament used routinely as an anodyne and antiseptic in dentistry and a food flavour and fragrance agent. The drug stimulates the superoxide (O2-.) release of guinea pig neutrophils without a lag time. The production rate increases with the drug concentration and reaches a plateau at 5 mM. However, the induction accompanies the cytotoxicity. The stimulation system of O2-. production is sensitive to mild heating (45 degrees C, 15 min). The system proceeds without artifacts which may be mediated by a radical chain reaction with H2O2 and hydroxy radical, since neither catalase, mannitol nor azide changes the rate. Ca2+ and Ni2+ in the medium enhance the activity, but Mg2+ and Zn2+ have no effect. EDTA inhibits completely, suggesting that intracellular metal ions are involved in this system. Phenolic compounds used as dental medicaments other than eugenol act as potent stimulators of the O2-. production, with the following order of potency: thymol greater than eugenol greater than o-cresol. Resorcinol, guaiacol and hexachlorophene show little activity. This order of potency agrees with the order of hydrophobicity of these chemicals and that of the cytotoxicity to neutrophils. The data suggest that phenolic antiseptic drugs bind to the cell surface hydrophobically, trigger the oxygen burst and make the plasma membrane fragile at a high dose of drugs.

Isolation and characterization of histamine-releasing peptides from human parotid saliva

Peptides responsible for releasing histamine were purified from human parotid saliva. The amino acid composition of the peptides showed a high proportion of histidine, lysine and arginine. Molecular weights of these peptides were between 3000 and 5000 as determined by SDS-acrylamide gel electrophoresis. These peptides induced histamine release from rat-isolated mast cells accompanied with degranulation in a dose-dependent manner over the concentration range 5-50 micrograms/ml.

Histamine-release induced by 7S nerve-growth factor of mouse submandibular salivary glands

The 7S nerve-growth factor (7S NGF) purified from mouse submandibular glands induced histamine release from rat-isolated mast cells in the presence of lysophosphatidyl-serine. When 7S NGF was injected intradermally into the rat skin, the vascular permeability increased. This response was abolished by the antihistamine, diphenhydramine. These results show that 7S NGF acts as a potent histamine releaser.

Histamine release induced by dynorphin-(1-13) from rat mast cells

Dynorphin is a potent opioid peptide. A synthetic dynorphin-(1-13) (Dyn) induced histamine release accompanied by degranulation from isolated rat mast cells in a dose-dependent manner over the concentration range 10(-7)-10(-5) M. Dynorphin-(1-13)-induced histamine release completed within 10 sec at 37 degrees C, and the release was not accompanied by the leakage of lactate dehydrogenase. Calcium (10(-5)-10(-3) M) enhanced the release, although higher concentration than 10(-3) M suppressed the release. The pH for the maximum release by Dyn was about 7.3. Disodium cromoglycate (5 X 10(-6)-10(-4) M) inhibited the histamine release by Dyn, but naloxone and leucine-enkephalin did not. These results indicate that Dyn-induced histamine release was not mediated by opioid receptors of the mast cells. Its mode of action appeared to that of anaphylactic histamine release.

The distribution of keratin type intermediate-sized filaments in so-called mixed tumour of the skin

Epithelial cells can be distinguished from various non-epithelial cells by the presence of keratin-type intermediate-sized filaments, which can be detected by immunofluorescence microscopy, using antibodies to alpha-keratin. In the present study, two types of antibodies were obtained. One of them was specific for alpha-keratin (mol. wt. 49,000 to 69,000 daltons) in whole epidermis, and the other for alpha-keratin (mol. wt. 62,000 and 69,000 daltons) in prickle and granular cells but not in basal cells. Four cases of so-called mixed tumour of the skin were studied by immunofluorescence microscopy using these antibodies. Tumour cells nests of cuboidal and polygonal cells, tubular structures and keratinous cysts reacted with these antibodies, as did individually-dispersed tumour cells within the myxoid and chondroid matrix. These results indicate that all the tumour cells of the so-called mixed tumour of the skin are of epithelial origin. Differences in staining intensity between these tumor cells and their specificity for these two antibodies are discussed with reference to keratin differentiation in tumour cells.

Dimeric hemoglobin of the bivalve mollusc Anadara broughtonii: complete amino acid sequence of the globin chain

The complete amino acid sequence of a dimeric hemoglobin (HbI) from the marine bivalve mollusc Anadara broughtonii was determined by sequencing of the intact chain and peptide fragments produced by cleavage at two asparaginylglycine bonds and at methionyl, arginyl, and tryptophanyl residues. The clam hemoglobin consists of two identical polypeptide chains. The globin chain has 146 amino acid residues with a proline at the NH2 terminus and a leucine at the COOH terminus. The calculated molecular mass of the native hemoglobin was 32945 daltons. The clam hemoglobin contains only two histidine residues, which correspond to the distal and proximal heme-linked positions. Compared with human beta chain, an additional segment of seven residues is present in the NH2-terminal region and also five less residues in the COOH-terminal region. Although such an amino-terminal elongation has been known to be characteristic of hemoglobins from the most primitive living vertebrates Cyclostomata, a very similar structure was found to occur in the hemoglobin from the primitive invertebrate arcid clam.

Ligand-dependent polymerization of tetrameric hemoglobin from the blood clam Anadara broughtonii

Hemoglobin (Hb II) of the blood clam Anadara broughtonii has a alpha 2 beta 2 sub-unit structure in athe oxy form with a sedimentation constant of 4.8 S. When deoxygenated, Hb II polymerizes with a major component, S20,w = 11.5 (above 150 microM in heme). Deoxy polymerization was not observed in a highly diluted protein below 20 microM (in heme). Gel filtration of Hb II in the deoxygenated state indicated that the major component has an apparent molecular weight of 195 000, which corresponds to a dodecamer. However, the sedimentation pattern and the elution profile of gel filtration showed the polymerization to be somewhat asymmetric. These results suggest that deoxy Hb II may polymerize with different polymerization states. We examined oxygen equilibria of Hb II in a range of 3--180 microM (in heme). Influences of the polymerization on its oxygen affinity and cooperativity were found to be very small. We have also found that the deoxy polymerization was completely prevented when all the sulfhydryl groups of the hemoglobin molecule were modified with p-chloromercuribenzoate.

Ligand-dependent allosteric transformation of hemoglobins from the blood clam, Anadara broughtonii

1. Oligomeric Hb I and II of Anadara broughtonii, which are unusual with respect to having no Bohr effect, were shown to have a R-T transformation on ligand-binding on the basis of the following experimental results. (a) Iodoacetamide reacted preferentially with the oxyiforms of the hemoglobins. (b) CD spectra at the far-ultraviolet regions significantly changed on ligand-binding. (c) 1-Anilinonaphthalene-8-sulfonate bound to the hemoglobins with a preference for deoxyforms. From these results and previous findings [1], it is concluded that the absence of the Bohr effect in these hemoglobins is due to the lack of the Bohr proton ionizing groups in the molecules. 2. Hb I and II treated with p-chloromercuribenzoate, designated as PMB-I and PMB-II, showed greatly increased oxygen affinity and decreased cooperativity. CD spectra at the far-ultraviolet of the PMB-Hb in the oxygen liganded state gave similar patterns to those of native oxygenated Hb. However no changes in the spectra were observed on deoxygenation. These findings suggest that the PMB-I and PMB-II retain their native oxy conformation even in the deoxy states. The PMB-modification might prevent the initial ligand-induced conformational change within the protomers.

Cadmium effects on bone and dental tissues of rats in acute and subacute poisoning

Injection of cadmium chloride to rats fed by normal calcium diet induced distrubances of tibia and incisor hard tissues metabolism. It is suggested that there may be the possibility of direct cadmium actions on those hard tissues metabolisms.

Subunit structure of hemoglobins from erythrocytes of the blood clam, Anadara broughtonii

Intracellular hemoglobins of the sea blood clam Anadara broughtonii consist of HbI dimer (33%) and HbII tetramer (60%). The molecular weights of globins of HbI and HbII were determined by sodium dodecyl sulfate (SDS)-gel electrophoresis to be 15,500 and 16,500, respectively. The existence of two dissimilar chains, alpha and beta, in globin from HbII tetramer was confirmed electrophoretically and the chains were separated by CM-cellulose chromatography in 8 M urea. In contrast, globin from HbI dimer showed a single band on two types of electrophoresis. The NH2-terminus and the COOH-terminus of HbI were determined to be proline and leucine, respectively. From the results of finger-printing, the alpha and beta chains from HbII were considered to have a rather similar profile, whereas globin from HbI was very different. The results obtained by amino acid analysis of each chain also supported the above findings. It was thus shown that HbII has an alpha2beta2 subunit structure, which is rare among invertebrate hemoglobins. On the other hand, HbI seems to have two identical subunits, designated as "gamma", and to exist as a "gamma2" dimer structure. Both Anadara Hb's appear to have no functional groups relating to the Bohr effect and to be unable to form a binding site for organic phosphates.

Novel optical waveguide for integrated optics

A novel dielectric optical waveguide was made consisting of a guide pattern on a thin dielectric film. Almost all the power propagates in the thin film along the guide pattern. The existence of propagation modes of this waveguide was verified both theoretically and experimentally.