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H Hashimoto

Publications and source records attributed to H Hashimoto.

At least 721 records · Page 40Linked to original sources
PubMed1993

Albumin-binding superoxide dismutase with a prolonged half-life reduces reperfusion brain injury.

To test the possible involvement of superoxide radicals in the pathogenesis of reperfusion injury, we synthesized a superoxide dismutase (SOD) derivative [poly(styrene-co-maleic acid) butyl ester (SM) covalently linked to SOD] that circulates bound to albumin, has a prolonged in vivo half-life, and accumulates in pH-decreased tissues. The protective effects of SM-SOD on regional cerebral blood flow, intracranial pressure, cardiac index, vascular permeability, and neurological outcome were investigated using a model of global brain ischemia in dogs. Intra-arterial injection of SM-SOD (10 mg/kg) just before reperfusion increased reactive hyperemia (SM-SOD, 160 +/- 36 ml.100 g-1.min-1, means +/- SD, n = 6; control, 100 +/- 34 ml.100 g-1.min-1, n = 6, P = 0.015), ameliorated delayed hypoperfusion (7 h after ischemia: SM-SOD, 40 +/- 14 ml.100 g-1.min-1; control 17 +/- 6 ml.100 g-1.min-1, P = 0.003), vascular permeability, and neurological outcome without affecting the cardiac index. These results indicate that superoxide radicals and/or their metabolite(s) might play a critical role in the pathogenesis of reperfusion injury in the brain.

Animals↗
PubMed1993

Secondary mucinous adenocarcinoma of the prostate in a patient with ulcerative colitis.

Herein we report a rare case of prostatic invasion of rectal carcinoma in a patient with ulcerative colitis. Malignant transformation is a well-known complication of long-standing ulcerative colitis. Mucinous adenocarcinoma, with positive carcinoembryonic antigen and negative prostate-specific antigen, strongly suggested the rectal origin of the tumor.

Adenocarcinoma, Mucinous↗
PubMed1993

Cilostazol, a novel cyclic AMP phosphodiesterase inhibitor, prevents reocclusion after coronary arterial thrombolysis with recombinant tissue-type plasminogen activator.

Inhibitors of cyclic nucleotide phosphodiesterase hydrolysis of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate are known to inhibit platelet aggregation, which plays an important role in acute reocclusion after thrombolysis in acute myocardial infarction. In the present study of a canine preparation of coronary artery thrombosis superimposed on high-grade stenosis, we tested whether the antithrombotic agent cilostazol, an inhibitor of cAMP phosphodiesterase, could prevent acute reocclusion or sustain coronary blood flow after thrombolysis when used with recombinant tissue-type plasminogen activator (rt-PA) and heparin. Intravenous infusion of rt-PA (0.5 mg/kg body wt for 30 minutes) and heparin (a 150 IU/kg body wt i.v. bolus and then 25 IU/kg body wt per hour i.v.) was combined with cilostazol (0.6 or 1.8 mg/kg body wt for 60 minutes). Without cilostazol, reperfusion was observed in seven of eight dogs, but reocclusion occurred in six of these seven dogs after 9 +/- 2 minutes. After administration of 1.8 mg/kg body wt cilostazol (group B-2; a 120-minute observation after the start of rt-PA infusion), reperfusion occurred in all seven dogs (p < 0.05 versus control group), and brief cyclic reocclusion was observed in only one dog 63 minutes after reperfusion. At the same dose of cilostazol (group B-2L; a 240-minute observation after the start of rt-PA infusion), reperfusion occurred in all five dogs (p < 0.05 versus control group), and coronary blood flow was well maintained except for one short reocclusion in one dog. Cilostazol inhibited cyclic flow reduction in a dose-dependent fashion.(ABSTRACT TRUNCATED AT 250 WORDS)

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1993

Rate of successful recording of blood flow signals in the middle cerebral artery using transcranial Doppler sonography.

BACKGROUND AND PURPOSE: To assess the usefulness of transcranial Doppler sonography, we investigated the rate of blood flow signal recording failure in the middle cerebral artery in Japanese subjects. Furthermore, we studied the effect of increased emitted power on the rate of successful recording in some of the patients in whom recording failure had been detected at the standard transducer power of 100 mW/cm2. METHODS: To evaluate the rate of successful recording, we measured blood flow signals in 597 patients (age range, 16 to 89 years) for screening of cerebrovascular disease by using a 2-MHz range-gated, pulsed-wave Doppler instrument at the standard transducer power. In 18 elderly patients with recording failure at the standard power, we assessed the effect of increased emitted power of 400 mW/cm2 on flow signal recording. RESULTS: Blood flow signals were recorded in 920 (77.1%) of the 1194 middle cerebral arteries of the 597 patients studied. The rate of successful recording of bilateral middle cerebral artery flow signals (70.9%; 423 of 597 patients) decreased with age, especially in females (17.0% in women aged 70 years or older). In 12 of 18 elderly patients with recording failure at the standard power, blood flow signals could be detected at the increased emitted power of 400 mW/cm2. CONCLUSIONS: The rate of successful recording of blood flow signals in Japanese subjects decreases with advancing age, especially in females. Increasing the emitted power markedly improves the successful recording rate.

Adolescent↗
PubMed1993

Effects of intravenous anesthetics, thiopental, fentanyl, and morphine on ventricular delayed activation in a canine myocardial infarction model.

We examined the effects of intravenous anesthetics (thiopental, fentanyl and morphine) on the ventricular activation in a canine myocardial infarction model. Thiopental at 5 and 10 mg/kg delayed or abolished the delayed activation in the infarcted zones with slight delay of activation of the normal zones. Fentanyl at 30 micrograms/kg slightly but significantly prolonged the activation time in both normal and infarcted zones. Morphine at 1 mg/kg did not produce any significant effect. Thiopental, but neither fentanyl nor morphine, inhibited ventricular stimulation-induced arrhythmias. Thus, thiopental, but not fentanyl nor morphine, markedly depressed the delayed activation in myocardial infarction, which may affect and probably inhibits the ventricular arrhythmias in myocardial infarction. It also should be kept in mind that thiopental may have arrhythmogenic effects in myocardial infarction.

Action Potentials↗
PubMed1993

An increase of 63 kDa-protein present in the cell membranes of Staphylococcus aureus that bears a plasmid mediating inducible resistance to partial macrolide and streptogramin B antibiotics.

A plasmid, pEP2104 (23.9 kilobase pairs), from Staphylococcus aureus carries a gene that specifies inducible resistance to 14-membered (erythromycin, EM, and oleandomycin, OL) and 16-membered macrolide (mycinamicin I and II), but not to all of the latter, and to streptogramin type B antibiotics (partial macrolide- and streptogramin-B-antibiotic resistance: PMS-resistance) (L. Jánosi, E. Bán, Acta Microbiol. Acad. Sci. Hung., 29, 187 (1982) and Y. Nakajima et al., J. Pharmacobio-Dyn., 15, 319 (1992)). The induced cells of strain 8325(pEP2104) did not inactivate EM, OL, josamycin, rokitamycin or mikamycin B (MKM-B), and the cell-free extract of the strain did not inactivate EM or MKM-B, either. Ribosomes from the cells whose PMS-resistance was induced by EM were sensitive not only to EM or spiramycin, but also to MKM-B. A 63000-dalton protein increased to a great extent only in the cell membrane fractions of induced 8325(pEP2104), and may be involved in PMS-resistance.

Anti-Bacterial Agents↗
PubMed1993

Acute myocardial infarction due to coronary embolization from left atrial myxoma.

We encountered a 67-year-old woman with a left atrial myxoma which was discovered during echocardiographic examination and emergency coronary arteriography just after an onset of acute inferior myocardial infarction. Coronary arteriography disclosed an abrupt and total occlusion of the right coronary artery and an abnormally large and tortuous atrial circumflex branch feeding a left atrial mass. These findings were the most useful for diagnosis. Aorto-coronary bypass surgery and excision of the myxoma were performed simultaneously by emergency operation. The postoperative course was uneventful. Myocardial infarction in this patient is believed to have been caused by coronary embolization from the left atrial myxoma.

Adolescent↗
PubMed1993

Enhanced elevation of blood pressure during cigarette smoking in the elderly.

Acute changes in blood pressure and heart rate during cigarette smoking were investigated in 10 elderly subjects aged 75.6 +/- 4.8 (mean +/- SD) years and in 10 non-elderly subjects aged 35.6 +/- 10.5 years. All subjects were healthy normotensive men with no cardiovascular disease. While each subject smoked two cigarettes containing 5.4 mg of nicotine, systolic and diastolic blood pressures increased significantly more in the elderly subjects (18.2 +/- 6.0/9.0 +/- 5.0 mmHg) than in the non-elderly subjects (4.8 +/- 4.7/3.9 +/- 4.2 mmHg, p < 0.05). However, the increases of heart rate in the two groups were similar (elderly: 10.5 +/- 4.1 beats/min versus non-elderly: 12.1 +/- 6.4 beats/min, ns). These results indicate that there is an age-related difference in blood pressure elevation during cigarette smoking in healthy subjects.

Adult↗
PubMed1993

Effects of semotiadil fumarate, a novel calcium antagonist, on blood pressure and heart rate in conscious spontaneously hypertensive rats.

The acute antihypertensive effects of orally administered semotiadil, a novel calcium antagonist, were compared with those of nifedipine and diltiazem in conscious, unrestrained spontaneously hypertensive rats (SHRs). Semotiadil (10 and 30 mg/kg) produced a dose-dependent hypotension that persisted for 18 hr at 30 mg/kg. Diltiazem (30 and 100 mg/kg) and nifedipine (1 and 3 mg/kg) also exhibited hypotension dose-dependently, but their durations of actions were shorter than that of semotiadil. Semotiadil caused a slight increase in heart rate, while diltiazem and nifedipine caused a bradycardia and a marked tachycardia, respectively. These results suggest that semotiadil has a beneficial property as an antihypertensive drug.

Animals↗
PubMed1993

Dot-blot hybridization using digoxigenin-labeled cDNA probe complementary to the S1 gene of avian infectious bronchitis virus permits discrimination between virus strains.

Digoxigenin-dUTP-labeled DNA probe was prepared from a cDNA clone complementary to the gene encoding S1 region of the spike protein of infectious bronchitis coronavirus (IBV) strain M41. The probe exclusively reacted with four strains at 56 degrees C which were grouped to the same serotype as the strain used for the probe. In contrast, at 68 degrees C, the probe reacted only with the homologous strain and did not react even with the strains belonging to the same serotype. The dot-blot hybridization thus appeared serotype-specific at 56 degrees C and strain-specific at 68 degrees C. In addition, it was revealed that the S1 gene has some nucleotide sequence variation even among strains in the same serotype. This technique should be applied to determining serotypes of the virus isolates and to differentiating field isolates from the vaccine strain.

Animals↗
PubMed1993

Double-orifice mitral valve with three papillary muscles.

A case of double-orifice mitral valve in a 16-year-old Japanese boy is presented. Two-dimensional echocardiography, including transesophageal approach, showed two approximately equal orifices with three papillary muscles. Color Doppler echocardiography showed a mild mitral regurgitation from both orifices. No other cardiac anomaly was associated. The patient's left ventricular function is presently normal.

Adolescent↗
PubMed1993

Falciparum malaria in an overseas traveler complicated by disseminated intravascular coagulation and pulmonary edema.

A 24-year-old woman was infected with falciparum malaria during travel to Kenya, complicated by intravascular coagulation and pulmonary edema. She was successfully treated with anti-malarial drugs including chloroquine, quinine sulfate and pyrimethamine, with a combined regimen of heparin, antithrombin III and nafamostat mesilate for disseminated intravascular coagulation, and with methylprednisolone pulse therapy for pulmonary edema. The present case emphasizes the importance of early diagnosis and appropriate treatment in terms of falciparum malaria. This case, in particular, is believed to be worth reporting as overseas travel is increasing and yet anti-malarial drugs are not readily available to most physicians in Japan.

Adult↗
PubMed1993

Disseminated intravascular coagulation in a patient with systemic lupus erythematosus with lupus anticoagulant.

A 19-year-old female patient with systemic lupus erythematosus (SLE) who had lupus anticoagulant (LA) and concurrently developed disseminated intravascular coagulation (DIC) during an exacerbation of "central nervous system (CNS) lupus". Since no other indications or causes for DIC could be demonstrated, she was treated with prednisolone and anticoagulants, which rapidly alleviated her DIC condition as well as "CNS lupus". Although abnormalities of coagulation are frequently reported in SLE patients, DIC rarely occurs in patients with SLE without associated complications. A review of the pathogenesis of DIC in patients with SLE is discussed.

Adolescent↗
PubMed1993

Role of prostaglandin H2 as an endothelium-derived contracting factor in diabetic state.

This study investigated the possible involvement of prostaglandin H2, an acetylcholine-induced endothelium-derived contracting factor in rat aorta, in the development of abnormality of the vasculature in diabetes. Rings of thoracic aorta were prepared from control Wistar-Kyoto and STZ-induced diabetic rats to examine the changes in isometric tension. In 10(-7) M norepinephrine-precontracted rings, acetylcholine induced relaxations, which were significantly impaired in diabetic rats. Inhibition of thromboxane A2-prostaglandin H2 receptors with ONO-3708 (10(-6) M) prevented the development of the impairment of relaxation in diabetic rats. Thromboxane A2 synthesis inhibition with OKY-046 (10(-5) M) did not affect the acetylcholine-induced relaxation in both control and diabetic rats. In aortic rings under resting tension, acetylcholine induced a contraction that was greater in diabetic than control rats, when the nitric oxide production was inhibited by NG-nitro-L-arginine methylester (10(-4) M). This acetylcholine-induced contraction was observed only in the rings with intact endothelium and was completely abolished by ONO-3708 (10(-6) M). The concentration of 6-keto-prostaglandin F1 alpha in the solution bathing diabetic rat aortic rings increased significantly after acetylcholine (10(-5) M) administration. Prostacyclin (10(-9)-10(-6) M) did not induce contractions at all. Prostacyclin is unlikely to mediate contractions because of its low contractile potency.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcholine↗
PubMed1993

[Gastric ulcer and patterns of distribution of intestinal metaplasia in the elderly].

Gastric ulcer was studied with regard to the relationship with patterns of distribution of intestinal metaplasia (IM). 882 stomachs of elderly patients, obtained from autopsies from 1987 to 1991 were examined histopathologically. There were 74 open gastric ulcers and 88 ulcer scars. Distribution of IM was classified into 7 types. Open ulcers and scars were found more often in type O (IM found in the entire lesser curvature which is the most common type in the elderly) than in other types. Open ulcers in type O were mostly shallow and located in the IM area. Many open ulcers in type A (IM involving the antrum) and type B (IM involving both the antrum and cardia) were deep and on the boundary zone between the IM area and the proper gastric mucosa area. Most of the deep scars that did occur in type O were in the IM area but in types B and A most of them were located on the boundary zone. Scars in type O probably developed on the boundary zone when they were open ulcers and removed in the IM area because of progression of the IM area. In some cases ulcers were at the boundary zone of IM involving the cardia and this finding was characteristic of elderly cases.

Aged↗
PubMed1993

[Postoperative results of ligation of crura penis for impotence with corporal veno-occlusive insufficiency].

We performed ligation of the crura penis for 34 impotents with corporal veno-occlusive insufficiency without arterial insufficiency and neural dysfunction from October 1987 to April 1991. Ages ranged from 24 to 72 (52.6 +/- 12.7) years old and follow up period was from 1 to 41 (17.7 +/- 12.6) months. For six patients ligation of the crura only was performed, for 22 ligation of the crura and deep dorsal vein (DDV) as well was performed at the same time, and for 6 crural ligation was performed after ligation of DDV. These operations required less than one hour and there were no severe complications. The postoperative results at 1 month were as follows: Excellent (sufficient spontaneous erection was recovered); 18, Improved (complete erection with intracavernous papaverine injection was achieved); 13, and Failure; 3. Erectile function was maintained only in 50% of the 18 pts. graded excellent. Ninety percent of the 31 patients graded either excellent or improved could maintain erectile function after 40 months with papaverine injection. Venous surgeries could not be a primary treatment for correcting the outflow abnormalities (of the veins). So it is conceivable that failure or recurrence could occur during a long follow up period. We concluded that crural ligation was acceptable as the first line treatment for erectile dysfunction due to corporal veno-occlusive insufficiency because of its relative non-invasiveness compared to other venous surgeries.

Adult↗