A surgical case of aortic regurgitation with Beh?et disease

A case of Beh?et disease associated with aortic valve regurgitation treated with aortic valve replacement is reported. The patient was treated successfully with special surgical techniques for prevention of post operative paravalvular leakage and occurrence of pseudo aneurysm because the patient was under long-term steroid therapy for Beh?et disease.     

Dendritic morphology of interstitial amacrine cells with monostratified dendrites in different-sized carp retinas.

The dendritic morphology of a class of interstitial (IS) amacrine cells in retinas of different-sized carp (body length, 9.1-32.3 cm) was investigated by identifying their fluorescent nuclei pre-loaded with 4,6-diamidino-2-phenylindole (DAPI), followed by iontophoretic injection of Lucifer yellow (LY) in isolated and formaldehyde-fixed flat-mounts under microscopic control. The LY-injected fusiform or pyriform cell bodies were found to locate at the middle of the inner plexiform layer (IPL) or immediately beneath the amacrine cell layer, and their dendrites monostratified in sublamina b of the IPL. The pyriform cells had a short stem from which extended 4-5 stout dendrites, while the fusiform cells extended similar dendrites from the soma. The dendrites of both types of cell were decorated with spines and a few long axon-like processes. The pyriform cells were found more frequently in smaller retinas than in larger retinas, suggesting that the former may migrate proximally during retinal growth. The dendritic field sizes of these IS amacrine cells were wider as the fish became larger, while the dendritic morphology, analyzed by the Sholl's branching model, was very similar in smaller and larger retinas. The results indicate that the IS amacrine cells do not add dendrites, but that their dendritic trees simply expand during retinal growth.     

Sugi (Cryptomeria japonica D. Don) pollen scattering out of season]

We investigated the preseasonal blooming conditions of the male flowers of Sugi (Cryptomeria japonica D. Don) which flowers commonly in spring. We also investigated atmospheric Sugi pollen during all seasons for three years from 1988 through 1991 to determine pollen scattering in autumn. Our results showed that a discernible amount of pollen is scattered from the middle of October into December; this scattering would be expected in the following spring. Almost none of the buds of the flowers collected in October and in November bloomed when incubated at temperatures ranging from 6 degrees C to 20 degrees C after low-temperature treatment to arise the blooms from dormancy. However, small numbers of the male flowers from various Sugi trees bloomed and scattered pollen under these conditions. We found that the ratio of the blooming male flowers was one-third or less per blossom. The ratio changed depending on the growth stage and incubation conditions. In conclusion, the density of airborne Sugi pollen scattering is not high in autumn in general. However, the density would be expected to be high enough to induce allergic reactions and clinical symptoms in some areas of Sugi growth, especially in a good harvest year.     

Effects of Alkyl Alcohols and Related Chemicals on Rat Liver Structure and Function: III. Physicochemical Properties of Ethanol-, Propanol- and Butanol-treated Rat Liver Mitochondrial Membranes

The physicochemical properties of mitochondria in liver tissue obtained from rats given 32% ethanol, 32% propanol or 6.9% butanol in drinking water for up to 3 months were investigated using differential scanning calo-rimetry and fluorescence polarization measurements. The results obtained were as follows: 1) Phospholipids extracted from mitochondria showed increases in the relative amounts of phosphatidylcholine, phosphatidylinositol and phosphatidylserine, and a decrease in the relative amount of phosphatidylethanolamine. An increase in the unsatu-rated/saturated fatty acid ratio of phospholipids was also observed. 2) Elevation of the thermotropic lipid phase transition temperature with a decrease in the enthalpy value (δ H ) was revealed by differential scanning calo-rimetry. 3) The elevation of the lipid phase transition temperature was detected also by fluorescence polarization measurements using 1,6 diphenyl 1, 3, 5 hexatriene (DPH) as a probe. Elevation of mitochondrial membrane fluidity was found in some of the experimental animals, but most showed no changes in comparison with the control. A possible role of membrane fusion in the mechanism of formation of ethanol-, propanol- and butanol induced hepatic megamitochondria is discussed on the basis of these results. Acta Pathol Jpn 42: 549–557, 1992.     

A pressor response to vibration in conscious rats

Cardiovascular response in an alerted state induced by vibration was studied in conscious rats by giving a to-and-fro movement to their cages for 30 sec. Cardiac output, superior mesenteric flow, and hindquarter flow were observed with chronically implanted electromagnetic flow probes and arterial pressure with an indwelling catheter. Arterial pressure, heart rate, cardiac output and hindquarter flow increased and superior mesenteric flow decreased with vibration. The increase in heart rate was still present after adrenalectomy, but was abolished by beta-adrenoceptor blockade propranolol. The increase in hindquarter flow was greatly diminished by propranolol or after adrenalectomy, but was still present in adrenalectomized rats after alpha-adrenoceptor blockade phentolamine. The decrease in superior mesenteric flow in vibration was abolished by phentolamine. It was diminished by adrenalectomy. These findings indicate that the cardiovascular response to vibration includes excitation of the cardiac sympathetic nerves, adrenomedullary secretion, and excitation of sympathetic vasoconstrictor fibers and exercise hyperemia in skeletal muscles.     

Effects of exogenous [Arg8]-vasopressin on borderline-hypertensive Hiroshima rats

The interaction between [Arg8]-vasopressin and a vasopressin receptor antagonist, [d(CH2)5(1), O-Me-Tyr2, Arg8]-vasopressin, was examined in Hiroshima rats and normotensive control rats under pentobarbital anesthesia. [Arg8]-vasopressin dose-dependently increased the arterial pressure in both the Hiroshima and control rats, the pressor effect being greater in the Hiroshima rats. After the administration of a vasopressin antagonist (0.01 mg/kg), which by itself decreased arterial pressure only in the Hiroshima rats, the dose-response curve for [Arg8]-vasopressin was much more greatly shifted to the right in the control rats. These results indicate that with or without a vasopressin antagonist, the exogenous [Arg8]-vasopressin induced more powerful pressor actions in the Hiroshima rats compared to the control rats.     

Arterial infusion therapy with low-dose cisplatin and continuous 5-fluorouracil for isolated hepatic recurrence of gastric carcinoma

Patients with metachronous liver metastasis after curative resection of gastric carcinoma generally have a poor prognosis, even when recurrence is confined to the liver. We report a patient in whom hepatic arterial infusion therapy with bolus low-dose cisplatin (CDDP) and continuous 5-fluorouracil (5-FU) was effective against large metastases confined to the liver. An 83-year-old man was admitted with huge liver metastases from gastric carcinoma. Intra-arterial bolus injection of low-dose CDDP (5 mg) and continuous intra-arterial infusion of 5-FU (250 mg/day for 7 days) was started. After four courses of this arterial infusion therapy, computed tomography scans revealed shrinkage of the liver metastases. He was followed-up as an outpatient and continued to receive the arterial infusion therapy once every 4 weeks. Throughout the course of the chemotherapy, a partial response of the liver metastases was maintained. The patient had an improved quality of life after starting the chemotherapy, and he survived for 16 months from the commencement of the therapy. Arterial infusion therapy with bolus low-dose CDDP and continuous 5-FU may be recommended for patients with isolated hepatic recurrence of gastric carcinoma. Received: September 6, 1999 / Accepted: January 31, 2000     

Cardiac angiotensin II type 2 receptor activates the kinin/NO system and inhibits fibrosis

We have previously demonstrated that stimulation of the angiotensin (Ang) II type 2 receptor in vascular smooth muscle cells caused bradykinin production by activating kininogenase in transgenic mice. The aim of this study was to determine whether overexpression of AT2 receptors in cardiomyocytes attenuates Ang II-induced cardiomyocyte hypertrophy or interstitial fibrosis through a kinin/nitric oxide (NO)-dependent mechanism in mice. Ang II (1.4 mg/kg per day) or vehicle was subcutaneously infused into transgenic mice and wild-type mice for 14 days. The amount of cardiac AT2 receptor relative to AT1 receptor in transgenic mice was 22% to 37%. Ang II caused similar elevations in systolic blood pressure (by approximately 45 mm Hg) in transgenic mice and wild-type mice. Myocyte hypertrophy assessed by an increase in myocyte cross-sectional area, left ventricular mass, and atrial natriuretic peptide mRNA levels were similar in transgenic and wild-type mice. Ang II induced prominent perivascular fibrosis of the intramuscular coronary arteries, the extent of which was significantly less in transgenic mice than in wild-type mice. Inhibition of perivascular fibrosis in transgenic mice was abolished by cotreatment with HOE140, a bradykinin B2 receptor antagonist, or L-NAME, an inhibitor of NO synthase. Cardiac kininogenase activity was markedly increased (approximately 2.6-fold, P<0.001) after Ang II infusion in transgenic mice but not in wild-type mice. Immunohistochemistry indicated that both bradykinin B2 receptors and endothelial NO synthase were expressed in the vascular endothelium, whereas only B2 receptors were present in fibroblasts. These results suggest that stimulation of AT2 receptors present in cardiomyocytes attenuates perivascular fibrosis by a kinin/NO-dependent mechanism. However, the effect on the development of cardiomyocyte hypertrophy was not detected in this experimental setting.     

Disruption of the type 2 dopamine receptor gene causes a sodium-dependent increase in blood pressure in mice

BACKGROUND: Dopamine D(2) receptors (D(2)Rs) are expressed in the kidney. It has not been determined whether D(2)Rs are involved in the mechanism of sodium handling and blood pressure (BP) control. METHODS: The function of D(2)Rs was investigated in mice disrupted with D(2)R gene (D(2)KO mice). Six-week-old male D(2)KO mice and wild-type (WT) mice were fed high-salt (4% NaCl) or low-salt (0.01% NaCl) diets for 8 weeks. RESULTS: Before starting the metabolic diet, there were no significant differences in body weight, food consumption, and 24-h urine excretions of creatinine, sodium and potassium. The high-salt diet caused a significant elevation in systolic BP in D(2)KO mice but not in WT mice. Calculation of sodium and potassium balances revealed a significantly high level of sodium retention in D(2)KO mice placed on the high-salt diet. Twenty-four-hour urine norepinephrine excretions and heart rates, indicators of sympathetic activity, were not different in D(2)KO and WT mice on the high-salt diet. Administration of nemonapride, a specific D(2)-like receptor antagonist, to WT mice given 0.9% NaCl in drinking water caused suppression of urinary sodium excretion but had no effect in mice without salt loading. CONCLUSIONS: These results suggest that D(2) receptors promote sodium excretion during a period of high salt intake. A defect in this mechanism may result in sodium-dependent BP elevation.