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Biomedical subjects

T Nakada

Publications and source records attributed to T Nakada.

At least 415 records · Page 23Linked to original sources
PubMed1989

31P magnetic resonance spectroscopy of chronic cerebral infarction in rats.

The chronological changes in the pattern of 31P magnetic resonance spectroscopy (MRS) associated with cerebral infarction were studied in rats. 31P MRS of chronic infarction (1 month after induction of infarction) clearly showed a pattern distinct from that of normal brain. In chronic infarction, the relative phosphomonoester (PME) level was found to be significantly higher and relative phosphocreatine (PCr) level significantly lower compared to normal brain. The intracellular pH and the relative inorganic phosphate (Pi) level did not show any significant differences. Histological examination indicated that the 31P MRS pattern of chronic infarction reflects gliosis.

Animals↗
PubMed1989

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.

Adrenochrome↗
PubMed1989

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.

Aged↗
PubMed1989

Surgical experience in two-stage hypospadias repair.

Hypospadias can be categorized as glandular, penile, scrotal or perineal hypospadias. Diversified surgical procedures have been devised for the reparation of this congenital anomaly. The surgical method consists of 3 chief parts: avoidance of fistula formation, resection of the chordee and construction of the distal urethra. Infrequently a fistula following operation in this disease can be cured by urethral drainage, but in the majority of cases surgical repair is indispensable. Subsequently operative or postoperative complications must be decreased. The technical performance and accompanying problems for these points in the management of hypospadias are described.

Humans↗
PubMed1989

Sorbitol accumulation in heart: implication for diabetic cardiomyopathy.

Sorbitol levels in heart were determined in streptozotocin-induced diabetic rats. Significantly higher levels were found in hearts of diabetic rats compared to normal rats. The findings are compatible with either significantly higher de novo synthesis of sorbitol in heart than is generally believed or uptake of circulating sorbitol by heart as previously indicated by nuclear magnetic resonance (NMR) in vivo metabolic imaging. Sorbitol accumulation in heart tissue may play a role in the pathogenesis of diabetic cardiomyopathy as has been implicated in cataract formation.

Animals↗
PubMed1989

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.

Adenoma↗
PubMed1989

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.

Adult↗
PubMed1989

Relationship of lymph node metastasis to primary tumor size and microscopic appearance of roentgenographically occult lung cancer.

We investigated the relationship of lymph node metastasis to primary tumor size and microscopic appearance in 92 resected specimens obtained from patients with roentgenographically occult lung cancer (ROLC) located at a site along the airway between the main bronchus and the sub-subsegmental bronchi. Most of the patients were discovered by mass screening. All were treated surgically after bronchoscopic localization of cancer. The bronchial tree of the resected specimens was serial-sectioned into 2-mm thick blocks from the margin of resection to the sub-subsegmental bronchi. Bronchial wall invasion was noted in some blocks of all the specimens. The length of longitudinal extension (LLE) was defined as the product of the thickness and the number of consecutive blocks involved, counting from the most proximal to the most distal block. LLE was used as primary tumor size. Hilar and mediastinal lymph nodes were examined in 84 patients who underwent lymph node dissection. No nodal involvement was found in 59 cancers with LLE of less than 20 mm. Of 25 cancers with LLE of 20 mm or more, six showed nodal involvement. Eleven in situ carcinomas and four cancers of the "suspicious for invasion" type showed no lymph node metastasis. We contend that no lymph node dissection is required when pulmonary resection is performed for patients with ROLC if it is in situ carcinoma, if it is of the "suspicious for invasion" type, or if the LLE is smaller than 20 mm.

Aged↗
PubMed1989

Endomyocardial biopsy in children with Kawasaki disease.

To study the histopathology of the myocardium in Kawasaki Disease (KD) with various coronary angiographic findings, right endomyocardial biopsy specimens were evaluated on 20 boys and 16 girls with this disorder. KD with coronary artery lesions (CAL) showed various histopathological abnormalities, such as myocellular hypertrophy in 44%, degeneration in 61%, interstitial fibrosis in 44% and endomyocardial changes in 22%. KD without CAL revealed myocellular hypertrophy in 44%, degeneration in 50%, disarray in 28% and interstitial fibrosis in 6%. As in patients with long-standing KD, more than three years after onset, myocardial changes such as myocellular hypertrophy, disarray and interstitial fibrosis persisted, it is suggested that cardiomyopathy may develop in some patients with KD.

Cell Nucleus↗
PubMed1989

Cloning and nucleotide sequence of the gene (amyP) for maltotetraose-forming amylase from Pseudomonas stutzeri MO-19.

The gene (amyP) coding for maltotetraose-forming amylase (exo-maltotetraohydrolase) of Pseudomonas stutzeri MO-19 was cloned. Its nucleotide sequence contained an open reading frame coding for a precursor (547 amino acid residues) of secreted amylase. The precursor had a signal peptide of 21 amino acid residues at its amino terminus. An extract of Escherichia coli carrying the cloned amyP had amylolytic activity with the same mode of action as the extracellular exo-maltotetraohydrolase obtained from P. stutzeri MO-19. A region in the primary structure of this amylase showed homology with those of other amylases of both procaryotic and eucaryotic origins. The minimum 5' noncoding region necessary for the expression of amyP in E. coli was determined, and the sequence of this region was compared with those of Pseudomonas promoters.

Amino Acid Sequence↗
PubMed1989

Structural studies on milk of calcium in calyceal diverticulum.

Structural studies were performed on a renal specimen removed from a patient with milk of calcium in a calyceal diverticulum. Infrared spectroscopy revealed that stones consisted of crystals of calcium oxalate. On scanning electron microscopy and X-ray microanalysis, the intact surface of the stones was composed of weddellite and the fractured face of the stones showed calcium phosphate. Subsequently, stagnation is considered to be an important factor in the formation of milk of calcium.

Adult↗
PubMed1989

Collapse and reexpansion of lungs increase microvascular permeability in sheep.

The pathogenesis of reexpansion pulmonary edema has not been well studied. We tested the hypothesis that both long term collapse and subsequent reexpansion of the lungs cause reexpansion pulmonary edema by increasing pulmonary microvascular permeability. We investigated lymph dynamics in 15 experiments on collapsed lung and 10 experiments after lung reexpansion in 14 unanesthetized sheep with chronic lymph fistulas. We found that 24-hr left lung collapse increased lymph flow through the caudal mediastinal lymph node from the baseline of 1.71 +/- 0.97 (mean +/- S.D.) g/15 min to 2.01 +/- 0.99 g/15 min, although 2-hr collapse did not affect lymph flow. The L/P ratio did not fall below baseline in either experiment. Pulmonary arterial pressure increased by only about 6 cmH2O both in 2-hr and 24-hr collapse. Reexpansion after 24-hr lung collapse also increased lymph flow from the baseline of 1.64 +/- 0.52 g/15 min to 3.20 +/- 0.79 g/15 min during the first 2 hr after reexpansion. The lymph-to-plasma protein concentration ratio did not fall below the baseline. Reexpansion after 2-hr collapse did not affect these variables. We conclude that both long term lung collapse and subsequent reexpansion lead to reexpansion pulmonary edema by increasing pulmonary microvascular permeability.

Animals↗
PubMed1989

Culture and changes in dynamics of proliferation of pulmonary small cell carcinoma cells.

We had developed a method for the selective cultivation of cancer cells in short-term which was simple and required minimal technical skills. There have been so far 23 cases of pulmonary small cell carcinoma in which long-term passage of more than one year and establishment of a cell line were successful by the culture method. In particular, from November 1982 to March 1987, there were 29 patients who were diagnosed as having pulmonary small cell carcinoma on preoperative cytodiagnosis and whose cells were primary cultured. In 24 (83%) of these, isolation could be carried out in a short period and stable passage was possible. Long-term passage of more than one year and establishment of a cell line were successful in 21 (72%) of the 29 patients. As a result of primary culture of small cell carcinoma cells, a pattern of a suspended colony was observed in 22 (88%) of 25 cases. As passage advanced, the tendency toward attachment to the basal surface increased. The changes in dynamics of proliferation after long-term passage of more than one year were divided into three types: epithelial like cell type was observed in 8 (32%), the neurite like cell type was observed in 4 (16%) and the suspended colony type was observed in 13 (52%) of the 25 cases. Variant clones composed of relatively large cells appeared as a result of long-term passage or the use of carcinostatics in some pulmonary small cell carcinoma cells.

Animals↗
PubMed1989

A study of preservation solution for 48- and 96-hour simple hypothermic storage of canine lung transplants.

Forty-eight-hr and 96-hr simple hypothermic preservations of the lung were studied on dogs using 4 kinds of solutions resembling extracellular electrolyte compositions (Ep1-Ep4). The pH of each solution was changed from 6.377 to 7.463 by HPO4(2-)/H2PO4- ratio. Twenty dogs were prepared as donors (12 for 48-hr preservation with Ep1, Ep2 and Ep3, and 8 for 96-hr preservation with Ep3 and Ep4, respectively). The heart-lung block was removed from the donor, and flushed with 500 ml of preservation solution via the pulmonary artery, then immersed in the same cold (4 degrees C) solution, after which it was stored in a cold (4 degrees C) room. After preservation, the left lung was separated from the heart-lung block and was transplanted into the recipient orthotopically. The function of the transplanted lung was evaluated with serial x-ray findings, contralateral pulmonary artery ligation test, and histologic findings. In the case of 48-hr preservation, all of the four recipients with Ep3 (pH: 7.225) showed good aeration of the grafted lungs on the chest x-ray in the early postoperative period. As for the 96-hr preservation cases, one with Ep3 and three with Ep4 (pH: 7.463) presented good x-ray findings. Of these successful cases, seven dogs (5 of 48-hr preservation cases, six dogs tolerated this procedure. On histopathological examination of the successful cases, the 48-hr preservation cases showed almost normal pulmonary structure, while the 96-hr preservation cases showed slight degenerative changes in the alveolar walls. From the present study, it becomes apparent that clinical application of 48-hr preservation may be possible by using a phosphate buffered extracellular solution.

Animals↗
PubMed1989

Testosterone replacement therapy and prostate/seminal vesicle volume in Klinefelter's syndrome.

Volume of prostate and seminal vesicles was measured in patients with Klinefelter's syndrome by means of transrectal ultrasonography before and after testosterone replacement therapy. Continuous suppression of plasma gonadotropin levels was not observed, and plasma levels of testosterone did not maintain the normal range. However, volume of prostate (p less than 0.001) and seminal vesicles (p less than 0.05) increased significantly after testosterone replacement therapy. Volume determination of prostate and seminal vesicles by means of transrectal ultrasonography is an available parameter for evaluating the adequacy of testosterone replacement therapy in Klinefelter's syndrome.

Adult↗
PubMed1989

Adenomatoid tumor of the epididymis with special reference to immunohistochemical study of 3 cases.

Three cases of epididymal adenomatoid tumor are presented. The adenoid compositions of the tumors lined by epithelial cells showed a canalicular pattern with large vascular spaces, tubular pattern with glandlike regions or plexiform pattern with connective tissue strands. Immunohistochemistry demonstrated positive cytoplasmic staining for keratin, but negative for carcinoembryonic antigen and factor VIII-related antigen in each neoplastic tissue. These findings support the mesothelial origin of the epididymal adenomatoid tumors.

Adult↗
PubMed1989

[A primary adenocarcinoma of the appendix, accompanied with 5 ileocolonic fistulae].

A primary adenocarcinoma of the appendix is a rare lesion, and this paper reports a case of a primary adenocarcinoma of the appendix, but with the inclusion of 5 fistulae. According to the classification by Uihlein & McDonald, this histology is of the colonic type. The first known case accompanied with a fistula was reported by Haldane (1862) in the English-language literature and by Shiraishi et al. (1954) in Japan. Since then, 21 cases have been found in the Japanese literature. The patient underwent an operation and his prognosis has been considered good. A review of some the relevant literature is discussed with regard to the pathology, diagnosis, and treatment.

Adenocarcinoma, Mucinous↗