Biomedical subjects

A Mizuno

Publications and source records attributed to A Mizuno.

At least 181 records · Page 10Linked to original sources

PubMed1993

[Extraction of infected pacemaker electrode using catheter and snare].

A 85-year-old man had undergone implantation of a transvenous pacemaker system in 1982. Nine years later the generator was explanted and he was underwent implantation of a new generator and electrode. After one year of the second operation, infection of the old electrode had been noted and it was not cured in spite of partial explantation of the infected electrode and appropriate antibiotic therapy. We decided to remove the infected electrode and succeeded in extraction using catheter and snare. The patient's recovery was uneventful. We suggest catheter and snare is useful for explantation of chronic transvenous pacemaker electrodes.

Aged↗

PubMed1993

[Surgical treatment for impending rupture of distal aortic arch aneurysm: a case report using "elephant trunk" prosthesis].

A 75-year-old man with impending rupture of distal aortic arch aneurysm was operated on using the "elephant trunk" prosthesis. A long graft was anastomosed only to the proximal aortic stump and its distal free portion was inserted through the exit of the aneurysm into the descending aorta. Postoperative CT scan and MR image showed complete thrombosis formation in the dead space between the graft and the aneurysmal wall, which precluded necessity for further operation. However the graft was looped and kinked in the aneurysm. Furthermore the patient suffered from incomplete paraplegia, probably caused by the extremely long graft. In terms of promoting thrombosis formation in the aneurysmal inner space the longer prosthesis is feasible, but one should keep it in mind that an excessively long graft can lead to the kinking of the graft and paraplegia.

Aged↗

PubMed1993

[Excellent exposure for the mitral valve by means of dissection of the interatrial groove].

A technique to approach the mitral valve through a left atrial incision under dissecting the interatrial groove is described. The dissection of the interatrial groove makes the left atrial incision more anterior and medial. Therefore excellent mitral valve exposure was obtained. 40 of 61 mitral valvular procedures during past 1.5-year period were approached through this incision. We could achieve better exposure of the mitral valve than that of conventional atrial incision technique. This technique takes not so long time and rarely carries complications including dysarrhythmia and bleeding.

Cardiac Surgical Procedures↗

PubMed1993

[Analysis of water content in young rats brain edema by Raman spectroscopy].

Cerebral edema, classified into vasogenic edema and cytotoxic edema, has long been studied and recognized to be complicated. The authors studied the cerebral edema models of young rats suffered from cryo-injury and triethyl tin chloride (TET) injury by Raman spectroscopy which can physiologically evaluate the cerebral water content (%) of very restricted area. The cryo-injury model was conducted in the following manner. A cryo-probe (-196 degrees C) was contacted to the exposed cranium for 20 seconds in an anesthetized 4-5-week-old Sprague-Dawley young rat. A coronal section of the injured brain covered with a slide glass and wrapped by Parafilm was obtained 2, 4, 6, 8, 12, 24, 48, 72 hours after the cryo-injury in order to measure the water content by Raman spectroscopy employed by Tashibu and Huizinga. TET injury model was obtained by intraperitoneal administration of TET (4.5 mg/Kg). The water content was observed by the same manner as for the cryo-injury model. Subsequent to the cryo-injury, the water content of the white matter which seemed to be higher than in adult rats increased rapidly and persisted in the same condition within 72 hours. Subsequent to TET injury, the water content of the white matter increased more rapidly than that of the gray matter, however, in adult rats the water content of the gray matter showed more rapid increase than that of the white matter. Increased water content followed by TET injury was higher in adult rats than in young rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

PubMed1993

[Successful treatment of supravalvular mitral stenosis associated with ventricular septal defect].

Supravalvular mitral stenosis is a rare congenital anomaly. A case of a 2-year-old girl with supravalvular mitral stenosis and ventricular septal defect was successfully treated. The preoperated echocardiogram showed supravalvular mitral stenosis associated with congenital mitral stenosis and ventricular septal defect. However, the mitral valve was found to be normal after the excision of the ring. The ring has been attaching itself to the mitral valve, so it required a meticulous surgical technique to avoid injury to the mitral valve itself.

Child, Preschool↗

PubMed1993

[Anomalous origin of the left coronary artery from the pulmonary artery: a case report in an adult].

A 37-year-old female with anomalous origin of the left coronary artery from the pulmonary artery was surgically treated by creation of intrapulmonary aorto-coronary tunnel. Postoperative cardiac catheterization showed a minimal pulmonary stenosis at the baffle. But the remarkable preoperative ST-depression in a treadmill exercise test disappeared completely after operation and the normograde blood flow of the left coronary artery was detected from the ascending aorta.

Adult↗

PubMed1993

[Successful repair of total anomalous pulmonary venous connection and incomplete endocardial cushion defect associated with left isomerism].

Successful repair of a 8-month-old girl with polysplenia was reported. The cardiovascular anomalies were TAPVC (II b), incomplete ECD, interruption of inferior vena cava with hemiazygos continuation, bilateral superior vena cava, and left superior vena cava draining into the coronary sinus. Cardiopulmonary bypass was established with ascending aortic perfusion and caval cannulation. A left superior vena cava was directly cannulated after establishing partial bypass. In this case the left pulmonary vein drained into the right atrium near the orifice of the coronary sinus, so the atrial septal flap was made and sutured between the orifice of the left pulmonary vein and the coronary sinus in order to avoid late pulmonary vein obstruction. Then, atrium was separated by an intraatrial baffle which was sutured to the atrial septal flap. Recently, it becomes possible to surgical repair of polysplenia syndrome according to the advancements of the diagnostic methods, cardiopulmonary bypass, and the technique of the open heart surgery.

Abnormalities, Multiple↗

PubMed1992

Near-infrared FT-Raman spectra of the rat brain tissues.

Near-infrared Fourier transform (FT) Raman spectroscopy was applied to brain tissues in situ. The spectra were obtained from the cerebral cortex, white matter of the cerebrum, caudate-putamen, thalamus, synaptosomal fraction, and myelin fraction. High-quality Raman spectra in the 400 to 2940 cm-1 range were measured without interference of autofluorescence. Common spectral bands were assigned. The ratios of the intensity at 1664 (amide I), 1442 (CH2 deformation), 2885 (CH2 asymmetric stretching), 2938 cm-1 (CH3 symmetric stretching) could be used for differentiation between the gray and white matters.

Animals↗

PubMed1992

Simultaneous assay of adenosine deaminase and purine nucleoside phosphorylase activity as possible biochemical means to detect non-Hodgkin lymphomas of the oral cavity.

BACKGROUND AND METHODS: This study proposes the usefulness of simultaneous assay of adenosine deaminase (enzyme code [EC] 3.5.4.4; ADA) and purine nucleoside phosphorylase (EC 2.4.2.1; PNP) activities in a biopsy specimen as a biochemical test adjunctive to the histologic diagnosis of oral non-Hodgkin lymphomas (NHL). RESULTS: NHL tissues showed an ADA activity of more than 1428 nmol/h/mg of protein, and more than 3451 nmol/h/mg of protein was the sum of ADA and PNP activity. In contrast to this finding, all the 106 lesional tissues affected by various carcinomas, various benign tumors, various cysts, ameloblastomas, osteosarcomas, gingival hyperplasia, and inflammation showed an ADA activity of less than 1000 nmol/h/mg of protein, except for 2. The sum of ADA and PNP activity was less than 2249 nmol/h/mg of protein in these diseases, except for squamous carcinoma. Different control tissues of the oral cavity showed less than 766 nmol/h/mg of protein in ADA activity, and the highest sum of ADA and PNP activity in these was only 1384 nmol/h/mg of protein. CONCLUSIONS: These findings suggest that a strong suspicion of oral NHL is justified when the sum of ADA and PNP activity in a biopsy specimen exceeds 3000 nmol/h/mg of protein and ADA activity is greater than 1000 nmol/h/mg of protein.

Adenosine Deaminase↗

PubMed1992

Molecular aging of lens crystallins and the life expectancy of the animal. Age-related protein structural changes studied in situ by Raman spectroscopy.

In order to investigate the relationship of molecular aging of lens crystallins to an animal's life expectancy or to the type of the lens, Raman spectra have been measured in situ for rabbit and guinea-pig lens nuclei at various stages of aging; these spectra have been compared with those of rat and mouse lens nuclei previously reported. Lens aging results in pronounced differences among the Raman spectra of the lens nuclei of the four species. It is shown that the rates of dehydration, inter- and intramolecular disulfide bond formation, and microenvironmental changes in the tryptophan residues of lens crystallins are different among the four species. Much faster changes occur for rat and mouse, which have a shorter life expectancy (2 years) and give rise to hard lens nuclei while slower changes occur for rabbit and guinea-pig, which have a longer life expectancy (5-7 years), and give soft lens nuclei. In addition, the Raman data reveal, for all the species investigated, that there are correlations among the rates of the dehydration, the inter- and intramolecular disulfide bond formation, and the microenvironmental changes in the tryptophan residues. Therefore, there seems to be a common mechanism for molecular aging of lens crystallins among the four species, although the rate of the molecular aging strongly depends upon the life expectancy of the animal and the type of the lens. The most important factor determining the rate of the molecular aging is probably the dehydration which decreases free water in the lens nucleus.

Aging↗

PubMed1992

Correlation between residual beta-cell function and age at onset of spontaneous diabetes in Long Evans Tokushima lean rats.

We studied the natural course of disease in spontaneously diabetic rats, Long Evans Tokushima Lean (LETL) rats, to determine whether it showed similar pathogenetic heterogeneity to that of patients with insulin-dependent diabetes mellitus (IDDM) with regard to the relationships between age at onset, rapidity of disease progress, and degree of beta-cell function at the time of its manifestation. Type 1 diabetes developed in 35 rats (6.3%) between 40 and 140 days of age. Eight rats that became diabetic at age 69 days or less were more severely ketotic at the time of first detection of glycosuria and showed more rapid deterioration than seven rats that became diabetic later after birth (mean plasma 3-hydroxybutyrate levels, 4,707 +/- 1,215 pmol/L v 1,390 +/- 859 pmol/L; mean +/- SEM, P < .01). The mean plasma levels and pancreatic content of immunoreactive insulin (IRI) of the early onset rats, 47 +/- 13 pmol/L and 19 +/- 12 pmol/g tissue weight, were significantly lower (P < .01) than the corresponding values of the late-onset rats, 262 +/- 52 pmol/L and 348 +/- 87 pmol/g tissue weight, respectively. Both values were markedly lower than the mean values of 25 nondiabetic LETL rats, 976 +/- 122 pmol/L and 3,488 +/- 628 pmol/g tissue weight. Plasma immunoreactive glucagon (IRG) levels were significantly increased in the diabetic groups (early onset, 57 +/- 13 pmol/L; late-onset, 51 +/- 12 pmol/L; nondiabetic, 18 +/- 1 pmol/L; P < .01). These changes in pancreatic hormone levels of the early onset and late-onset rats were compatible with the histological features of their pancreatic islets.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗

PubMed1992

Effects of salicylate and other enhancers on rectal absorption of erythropoietin in rats.

To develop a new treatment for patients with anaemia in which erythropoietin (EPO) can be given without injection, the effects of promoters of the rectal absorption of EPO were studied. Recombinant human (rHu) EPO (5000 units) in a dosing solution or in a rectal suppository was placed in the rectum of healthy rats and changes in serum EPO levels were monitored by an enzyme-linked immunosorbent assay. Without a promoter, rHuEPO was not absorbed. Sodium glycocholate, sodium caprate, and sodium salicylate in the solution of rHuEPO increased the absorption of rHuEPO. Sodium salicylate or sodium caprate in the suppository with rHuEPO also increased its absorption. The bioavailability of rHuEPO in a suppository containing 5% sodium salicylate compared with that by an intravenous injection was 1.2%. rHuEPO given in rectal suppositories containing sodium salicylate and inserted once a day for 6 consecutive days increased erythropoiesis in peripheral blood.

Administration, Rectal↗

PubMed1992

Absorption and metabolism of pyridoxamine in mice. II. Transformation of pyridoxamine to pyridoxal in intestinal tissues.

The absorption of pyridoxamine from the intestine of the mouse was studied in whole animals. [3H]Pyridoxamine was orally administered and the distribution of isotope between the six recognized forms of vitamin B6 was determined in portal blood after the administration. When small doses (1.4 or 14 nmol) were administered, labeled pyridoxamine could hardly be found in the portal blood, although labeled pyridoxal and pyridoxal phosphate were found in the same blood. However, when a large amount (46 or 140 nmol) was given, a significant amount of labeled pyridoxamine was found with labeled pyridoxal and pyridoxal phosphate in the portal blood. These results suggest that a physiological dose of pyridoxamine is rapidly transformed to pyridoxal in the intestinal tissues and then released in the form of pyridoxal into the portal blood.

Administration, Oral↗

PubMed1992

Alteration of lens disulfide bonds in newly developed hereditary cataract rat.

A newly developed hereditary cataract rat named Shumiya Cataract Rat (SCR) is introduced. The lens opacity manifests spontaneously in the nuclear and perinuclear portions of the lens in this model at 11 weeks of age. Raman optical dissection studies reveal that lens protein disulfide bonds are considerably decreased in the SCR opaque lens nucleus. This tendency is also detected in the precataractous stage. The simultaneous increase of lens protein sulfhydryl groups is observed in the affected lens nucleus. The glutathione disulfide (oxidized glutathione) level, on the contrary, is elevated in the SCR opaque lens, whereas the glutathione sulfhydryl (reduced glutathione) level is decreased. It is suggested that the impaired formation of protein disulfide bonds is related to lens opacification in a hereditary manner.

Animals↗

PubMed1992

[Endoscopic closure of the postoperative bronchopleural fistula].

A case of successful endoscopic closure of a bronchopleural fistula with fibrin glue was reported. Fifty-eight-year-old man underwent right lower lobectomy for lung carcinoma. On the 21st postoperative day, he suffered from high fever and diagnosed as right side pyothorax. Then tube thoracotomy was done under UCG-guide. As a fistula in the right lower bronchial stump was found tiny by BFS, we tried to close the fistula bronchoscopically with fibrin glue. The fibrin glue was injected into the fistula via the ERCP tube, which was passed through the bronchoscope. This procedure was performed twice for two weeks interval. The fistula was completely closed about a month after the trial. This method is useful to close postoperative small bronchopleural fistula without surgical intervention.

Bronchial Fistula↗

PubMed1992

[Surgical treatment of coarctation of the aorta].

Repair of coarctation of the aorta was performed in 37 cases (31 patients, 6 patients of reoperation) ranging from 4 days old to 15 years old. Subclavian flap repair were performed in 15, resection and end-to-end anastomosis in 14, patch aortoplasty in 6, and interposition graft in 2. Subclavian flap angioplasty or end-to-end anastomosis is considered the procedure of choice in infants. However, the incidence of reoperation significantly increased in patients younger than age one month at initial subclavian flap repair. Mechanism of recurrent coarctation may be possibly related to retention of abnormal tissue, which is possibly ductal and/or intimal shelf, with the potential for proliferation and luminal narrowing. We suggest that in applicable case end-to-end anastomosis rather than subclavian flap angioplasty may be the surgical technique of choice in infants less than one month of age, and the most common reoperation technique was patch aortoplasty in re-stenosed cases.

Adolescent↗

PubMed1992

[Penetration of levofloxacin in bile].

The penetration into bile of a new pyridonecarboxylic acid derivative, levofloxacin (LVFX), was studied in a closs-over method with ofloxacin (OFLX) as the control drug in 6 post-operative patients. The lengths of time to the maximum concentrations in bile and the total areas under the curves were both almost the same for these 2 compounds, although the maximum bile concentration of LVFX was slightly lower than that of OFLX. A stability test for LVFX in human bile revealed that over 95.4% of the initial amount was recovered up to 24 hours after commencement of incubation at a room temperature, thus the stability in bile was similar to that in water. The penetration of LVFX which possesses twice as strong antibacterial activities as OFLX was similar to that of OFLX, suggesting that LVFX is useful against bile duct infections.

Aged↗

PubMed1992

[A case report of surgical treatment in acute aortic dissection: efficacy of retrograde cerebral perfusion and pitfall of image diagnosis].

A 76-year-old man with acute aortic dissection of Stanford type A underwent aortic arch replacement using retrograde cerebral perfusion for 105 minutes. By the preoperative IADSA an entry was detected in the distal arch. There were no neurological complications. But the postoperative IADSA showed that the surgically closed entry was another one from that diagnosed before operation. This case shows us efficacy of retrograde cerebral perfusion which allows more time for arch repair than the technique of deep hypothermia with circulatory arrest and importance of careful and precise evaluation by preoperative image diagnosis.

Aged↗