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Y Fujimoto

Publications and source records attributed to Y Fujimoto.

At least 361 records · Page 20Linked to original sources
PubMed1990

Flow cytometric DNA analysis of parathyroid tumors. Implication of aneuploidy for pathologic and biologic classification.

The previous cytometric studies on parathyroid tumors have provided conflicting data regarding the relationship between DNA content and histopathology, resulting from differences in technical methods and data analysis. This study measured nuclear DNA of parathyroid tumors by flow cytometry in fresh material and determined whether DNA aneuploidy really assists in making a pathologic diagnosis of carcinoma or not. From May 1987 through April 1989, 65 consecutive patients operated on for primary hyperparathyroidism had DNA analysis of the freshly excised parathyroid tumors. Three of the patients had metastatic lesions of parathyroid carcinoma in the lung, cervical lymph nodes, and lung and mediastinal lymph nodes, respectively. Pathologic classifications of the lesions from the other 62 patients were 54 adenomas, four carcinomas, and four hyperplasias. In all the latter patients, hyperplasia was associated with a multiple endocrine neoplasia syndrome. Unequivocal evidence of aneuploidy was found in all of the metastatic lesions and 60% of the primary lesions of the carcinomas, in 9% of the adenomas and in 50% of the hyperplasias. Therefore, parathyroid carcinomas were more apt to be aneuploid than were adenomas (P = 0.0015, both-sided testing). In each of the cases of aneuploid hyperplasia, a small aneuploid peak was found. The high incidence of aneuploidy in patients with multiple endocrine neoplasia type 1 may indicate the presence of clonal heterogeneity of hyperplastic glands and the presence of an abnormal subset of cells that have malignant potential. Cell distribution analysis did not provide any significant information beyond ploidy level. In conclusion, DNA flow cytometric analysis of DNA ploidy patterns is a valuable adjunct to the histopathologic diagnosis of parathyroid neoplasms.

Adenoma↗
PubMed1990

Active site of bovine adrenocortical cytochrome P-450(11) beta studied by resonance Raman and electron paramagnetic resonance spectroscopies: distinction from cytochrome P-450scc.

Cytochrome P-45011 beta was purified as the 11-deoxycorticosterone-bound form from bovine adrenocortical mitochondria and its active site was investigated by resonance Raman and EPR spectroscopies. Resonance Raman spectra of the purified sample revealed that the heme iron adopts the pure pentacoordinated ferric high-spin state on the basis of the nu 10 (1629cm-1) and nu 3 (1490 cm-1) mode frequencies, which are higher than those of the hexacoordinated ferric high-spin cytochrome P-450scc-substrate complexes. In the ferrous-CO state, a Fe2(+)-CO stretching mode was identified at 481.5 cm-1 on the basis of an isotopic substitution technique; this frequency is very close to that of cytochrome P-450scc in the cholesterol-complexed state (483 cm-1). The EPR spectra of the purified sample at 4.2 K showed ferric high-spin signals (at g = 7.98, 3.65, and 1.71) that were clearly distinct from the cytochrome P-450scc ferric high-spin signals (g = 8.06, 3.55, and 1.68) and confirmed previous assignments of ferric high-spin signals in adrenocortical mitochondria. The EPR spectra of the nitric oxide (NO) complex of ferrous cytochrome P-45011 beta showed EPR signals with rhombic symmetry (gx = 2.068, gz = 2.001, and gy = 1.961) very similar to those of the ferrous cytochrome P-450scc-NO complex in the presence of 22(S)-hydroxycholesterol and 20(R),22-(R)-dihydroxycholesterol at 77 K.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Cortex↗
PubMed1990

Inhibitory effect of a new androstenedione derivative, 14 alpha-hydroxy-4-androstene-3,6,17-trione (14 alpha-OHAT) on aromatase activity of human uterine tumors.

The development of human uterine estrogen-dependent tumors is considered to be closely related to estrogen biosynthesis. This study examined whether or not 14 alpha-hydroxy-4-androstene-3,6,17-trione (14 alpha-OHAT), a new 4-androstene-3, 17-dione derivative synthesized microbiologically, inhibits estrogen biosynthetase (aromatase) activities of human uterine tumors (i.e. uterine endometrial cancer, uterine leiomyoma and uterine adenomyosis tissues). 14 alpha-OHAT inhibited aromatase activity in all uterine tumors, dose-dependently (0.1-10 microM). Moreover, 14 alpha-OHAT did not show the binding affinity to rabbit uterine cytosol-sex steroids, and it was not converted to estrogen in human placental preparations. Thus, 14 alpha-OHAT, an aromatase inhibitor, may be useful clinically as an endocrine chemotherapy for peri- or post-menopausal women with uterine estrogen-dependent tumors.

Adult↗
PubMed1990

Effective use of rabbit gastric antral mucosal slices in prostaglandin synthesis and metabolism studies.

Intact slice preparations of rabbit stomach (antral mucosa, corporal mucosa, antral muscle and corporal muscle) were incubated and the released prostaglandins (PGs) were measured by reverse-phase high-performance liquid chromatography using 9-anthryldiazomethane for derivatization. With respect to total PG production, the highest amounts were generated by antral mucosal slices. Antral mucosal slices produced PGE2, 6-keto PGF1 alpha, thromboxane B2, PGF2 alpha and PGD2 (in descending order of magnitude) and possessed a high capacity for producing 13,14-dihydro-15-keto derivatives of both PGE2 and PGF2 alpha. Studies utilizing aspirin, EGTA or Ca2+ revealed that PG release by antral mucosal slices in the present in vitro system reflects a composite of the activities of phospholipase A3, PG cyclooxygenase and PG-metabolizing enzymes. These results show that antral mucosal slices will be useful in physiological and pharmacological studies on PG synthesis and metabolism of the stomach.

Animals↗
PubMed1990

Flow cytometric DNA analysis of parathyroid tumors with special reference to its diagnostic and prognostic value in parathyroid carcinoma.

The nuclear DNA content of paraffin-embedded parathyroid tumors from 49 patients with proven primary hyperparathyroidism was determined by flow cytometric analysis. The lesions included 14 primary and 11 locally recurrent or metastatic lesions from 16 carcinoma patients, 28 single adenomas from 28 patients, and 15 hyperplastic glands from five patients with familial multiple endocrine neoplasia type 1. No abnormal DNA stemline was found in any of the hyperplastic glands. One (3.6%) of the adenomas was aneuploid. There was no difference in ploidy patterns between the primary and recurrent lesions of the carcinomas and five (31%) of the carcinomas expressed aneuploidy. Four of the five patients with aneuploid carcinoma had recurrences including pulmonary metastases. One of them died of this disease 12 years after the initial operation, and all except one of the others are hypercalcemic even after removal of the successive recurrent or metastatic tumors. Of the 11 patients with diploid carcinoma, four had either local recurrence or pulmonary metastasis. Two of them are living with normocalcemia 3 and 6 years, respectively, after removal of the recurrent tumors and the others are alive with mild hypercalcemia. The remaining seven patients with diploid carcinoma, however, have no recurrence 2 to 5 years after the initial operation. Thus aneuploid parathyroid carcinomas are likely to show more malignant behavior than those with a diploid DNA pattern. All of the patients with adenoma and hyperplasia have been normocalcemic after a mean follow-up interval of 37 months. This study indicates that flow cytometric analysis of nuclear DNA content is a valuable adjunct to histologic examination in the diagnosis of parathyroid carcinoma and the prediction of the clinical outcome.

Adenoma↗
PubMed1990

Augmented enkephalin-immunoreactivity in adrenaline-producing phaeochromocytomas.

Immunohistochemical studies for methionine- and leucine-enkephalin were performed on 26 phaeochromocytomas to elucidate the patho-physiological roles of enkephalins. Positive reactions were seen in all phaeochromocytomas with varying intensities. The location of methionine- and leucine-enkephalin agreed fairly well with each other. Stronger immunostaining was obtained in phaeochromocytomas secreting both adrenalin and noradrenaline than in those secreting predominantly noradrenaline. Paroxysmal hypertension was frequently observed in patients with adrenalin-secreting phaeochromocytomas, especially those with marked enkephalin positivity. Urinary excretion of metanephrine was significantly correlated with enkephalin positivity. These findings show that all phaeochromocytomas retain the ability to produce enkephalins of the adreno-medullary or extra-medullary chromaffin tissues from which they derive. Augmented enkephalin-immunoreactivity in adrenalin-producing phaeochromocytomas may be interpreted as reflecting a close association of enkephalins with adrenalin under physiological conditions.

Adrenal Gland Neoplasms↗
PubMed1990

An immunohistological study of breast cancer--with special reference to the expression of carbohydrate antigens and estrogen receptor status.

An investigation carried out on 100 cases of primary breast cancer, both clinicopathologically and immunohistologically, revealed estrogen receptor (ER)-positive cases to be found significantly more often in early stage cancer than advanced stage cancer. On the other hand, ER negative cases were found to have a greater incidence of high-grade lymph node metastasis and were seen significantly more frequently in large tumors. Span-1, CA19-9, and SLEX antigens were detected in 33 per cent, 38 per cent, and 64 per cent of the total cases, respectively and the ratio of ER negative cases was significantly higher in each antigen positive group. Irrespective of the presence or absence of lymph node metastasis, ER negative cases were found significantly more often in antigen-positive groups than in their counterparts and tumor size tended to be greater in the antigen-positive cases. The results of this study thus indicated that the disease progression in breast cancer appears to be correlated with ER status and carbohydrate antigen expression.

Antigens, Neoplasm↗
PubMed1990

Aggressive fibromatosis in the neck. A case treated effectively by testolactone with a long follow-up study.

Extra-abdominal fibromatosis in the neck may occasionally cause serious sequelae when aggressive invasion of the vital structures occurs. However, the principle of wide excision is difficult to apply in some patients because of the important organs surrounding the tumor. We report herein, a woman followed up for 22 years, in whom testolactone showed a definite effect during the course of observation. She first presented, at the age of 52, with a painful tumor in the neck, located behind the right thyroid lobe and fixed to the adjacent structures. Incomplete excision of the tumor was followed by a local recurrence accompanied with recurrent laryngeal nerve palsy and Horner's syndrome on the right side. Prednisolone was administered for 2 1/2 months and external irradiation of 8,000 RAD was given. Enlargement of the recurrent tumor stopped but 2 months later an emergency tracheostomy was required for an airway obstruction. Over the next 3 years, the local findings remained unchanged, but then a painful tumor growth reappeared cephalad which gradually attained a size of 5 cm in diameter, and was fixed to the base. Testolactone 150 to 200 mg was given to the patient daily for 2 months, resulting in marked regression of the tumor. During the last 13 years the patient has been well with the tumor still decreasing in size.

Combined Modality Therapy↗
PubMed1990

Mid-mediastinal parathyroid lesions: preoperative localization and surgical approach in two cases.

Although hyperfunctioning mediastinal parathyroid lesions that require median sternotomy or thoracotomy for removal are occasionally present, the majority are located in the anterior mediastinum closely associated with the thymus. Only eight cases of ectopic hyperfunctioning parathyroid tumors in the middle mediastinum have been reported. We experienced two cases of either persistent or recurrent hyperparathyroidism in which abnormal parathyroid tissue was located in the aorticopulmonary window. One of the patients had a parathyroid adenoma and the other had metastatic lesions of parathyroid carcinoma. In both cases, thallium scanning proved useful in identifying the lesions while computed tomography scan was effective for mediastinal three-dimensional localization. In one case, single photon emission computed tomography imaging with thallium proved beneficial for both identification and localization of the middle mediastinal lesion. The surgical approach used in both cases was different. In one case, left thoracotomy was performed, after which the ligamentum arteriosum was divided, and an adenoma anterior to the left main bronchus and posterior to the left pulmonary artery removed. In the other case, two metastatic tumors of parathyroid carcinoma anterior to the right main bronchus and posterior to the right pulmonary artery were resected through a median sternotomy and opening of the pericardium.

Adenoma↗
PubMed1990

Primary adrenocortical micronodular dysplasia: enzyme histochemical and ultrastructural studies of two cases with a review of the literature.

The adrenal glands from two patients with primary adrenocortical micronodular dysplasia (PAMD) were studied (no. 1, a 23-year-old man with cardiac myxomas and sarcoidosis; no. 2, a 16-year-old girl). The PAMD cells showed intense activity of 3 beta-hydroxysteroid dehydrogenase (3 beta DH), succinate DH, glucose-6-phosphate DH, alkaline phosphatase (AlPase), and other DHs and lysosomal hydrolases, giving a characteristic staining pattern. The staining patterns correlated well with ultrastructural findings. The larger adrenals (no. 1: 16.6 g) were associated with larger black nodules and internodular cortex (INC) with fairly well-retained enzyme activities, and contained cell clusters and single cells with intense AlPase activity with the appearance of PAMD nodules in the buds. The smaller adrenals (no. 2: 5.4 g) were associated with smaller black/yellow nodules, and had INC with weaker enzyme activity. Analysis of descriptions of INC in 25 previously reported cases revealed that the larger adrenals (more than 10 g) had less atrophic INC than the smaller ones. The characteristic enzyme pattern in PAMD cells explains the paradox that PAMD adrenals smaller than normal can cause Cushing's syndrome, and may be useful for investigating neoplastic and non-neoplastic counterparts in other adrenal lesions. The relationship between PAMD cells and INC is not simply one of autonomy versus atrophy, and both cell types may be stimulated by a certain common trophic factor. Thus, PAMD belongs to the category of hyperplasia.

3-Hydroxysteroid Dehydrogenases↗
PubMed1990

Effects of metal ions on 15-hydroxy prostaglandin dehydrogenase activity in rabbit kidney cortex.

The effects of Cu2+, Fe2+ and Zn2+ on 15-hydroxy prostaglandin dehydrogenase activity in rabbit kidney cortex were examined. Cu2+ and Zn2+ (0.05-0.5 mM) inhibited the activity of this enzyme in a dose-dependent manner. The concentration required for 50% inhibition was approximately 0.1 mM for Cu2+ and 0.15 mM for Zn2+. The inhibition by both metals was uncompetitive and non-competitive with regard to NAD+ and prostaglandin E2, respectively, indicating that the mechanisms of the inhibition on the enzyme of both metals may be the same. Fe2+ had no effect on the activity of this enzyme. These results suggest that Cu2+ and Zn2+ have the potential to modulate the catabolism of prostaglandins by the kidney cortex.

Animals↗
PubMed1990

Purification and characterization of a kallikrein from human submaxillary glands.

A tissue kallikrein was purified over 1500-fold from the postmicrosomal supernatant of human submaxillary glands. The purified enzyme gave a single band, corresponding to an apparent molecular weight of 42,000 on SDS-polyacrylamide gel electrophoresis. This enzyme cross-reacted with the anti-human urinary kallikrein antiserum. The purified enzyme was characterized in comparison with the purest human urinary kallikrein preparation. Both enzymes hydrolyzed the synthetic substrate, Ac-Phe-Arg-OMe, most effectively. Aprotinin, TLCK, and PMSF suppressed the enzyme activities, while SBTI, LBTI, and alpha 1-antitrypsin had no effect at all. The purified enzyme generated kinin from the natural substrate, kininogen. It was concluded therefore that the purified enzyme is a typical tissue kallikrein.

Amino Acid Sequence↗
PubMed1990

Marked latency change of auditory brainstem response in preterm infants in the early postnatal period.

In order to evaluate the influence of extrauterine life on auditory brainstem response in neonates, we performed serial ABR recordings twice a week in 10 preterm infants. A marked decrease of I-III interpeak latency was observed in 7 infants during the first 2 or 3 weeks after birth. Wave I latency also remarkably reduced during this period in 5. These findings were related not to the conceptional age but to the extrauterine age. In 2 infants III-V interpeak latency increased during the first 1 or 2 weeks after birth, and the rate of latency increase seemed to be inversely proportional to that of decrease of I-III interpeak latency.

Aging↗
PubMed1990

Molecular characterization of 1,4-dihydropyridine-sensitive calcium channels of chick heart and skeletal muscle.

A monoclonal antibody designated as MAC-L1 immunoprecipitated [3H]PN200-110-labeled calcium channels of chick cardiac and skeletal muscle. On specific immunoprecipitation of 125I-labeled proteins, two large polypeptides (Mr 197,000 and 139,000 for heart, and 172,000 and 135,000 for skeletal muscle, under reducing conditions) were identified as the major components of these channels. Both polypeptides were found to exist together as a complex in 1% digitonin, but to become separated from each other in 1% Triton X-100. The 197 and 172 kDa peptides of cardiac and skeletal muscles, respectively, were photolabeled with [3H]azidopine. Under nonreducing conditions, the 139 kDa polypeptide of heart and the 135 kDa polypeptide of skeletal muscle took on larger molecular weights of 192,000 and 190,000, respectively. The 139 kDa but not the 197 kDa component of the heart was capable of binding to wheat germ agglutinin-Sepharose. Among the polypeptides specifically precipitated by MAC-L1, a 165 kDa peptide of skeletal muscle was phosphorylated by cAMP-dependent protein kinase. In contrast, a minor 99 kDa polypeptide, but not the major 197 kDa polypeptide, of the heart was phosphorylated by this kinase. These results suggest that the dihydropyridine-sensitive cardiac calcium channel has alpha 1 and alpha 2 subunits that are homologous but not identical to those of the skeletal muscle calcium channel.

Animals↗
PubMed1990

Two-dimensional electrophoretic analysis of hepatitis-associated polypeptides in liver of LEC rats developing spontaneous hepatitis.

High-resolution two-dimensional polyacrylamide gel electrophoresis in combination with silver staining was used to analyze between 800 and 1000 cytosolic and particulate polypeptides from age-matched livers of normal male Long-Evans rat with Agouti coat color (LEA) and Long-Evans rat with Cinnamon-like coat color (LEC) rats with hereditary trait of hepatitis at ages long before, immediately prior to, and just after the onset of hepatitis. Although the electrophoretic patterns of polypeptide expression were very similar with respect to the overall spot patterns, a number of polypeptides which differed either qualitatively or quantitatively were noted. Two constitutively expressed cytosolic polypeptides, P29.5 (Mr 29.5 kDa/pI 6.73) and P30 (30 kDa/6.70), were not detected in livers of LEC animals at any age. In the normal LEA rats both P29.5 and P30 were detected as early as one day after birth and both were expressed at similar concentrations at all ages. In the LEC rats P30-C (30 kDa/6.68) was constitutively expressed in close proximity to the expected position of P30, and P30-C was not detected in the LEA rats. By means of non-equilibrium pH gradient electrophoresis two relatively basic polypeptides were detected in the LEC rats. P18ne was detected immediately prior to and P27ne immediately after the clinical manifestation of hepatitis. Experiments in F1 backcross ([LEA x LEC] x LEC) animals, however, failed to demonstrate any genetic link between either the expression or lack of expression of P29.5, P30, P30-C, or P18ne and hepatitis development. P27ne was detected in all backcross animals exhibiting hepatitis, but was never observed in LEC rats prior to the onset of hepatitis. Although we were unable to identify any unique loss of expression of polypeptides which are genetically linked to hepatitis susceptibility in LEC rats, specific subsets of quantitatively modulated polypeptides were detected.

Animals↗
PubMed1990

Potent inhibition of prostaglandin inactivation in rabbit gastric antral mucosal slices by selenium ions in-vitro.

The effect of selenium ions on prostaglandin (PG) catabolism and synthesis in rabbit gastric antral mucosal slices has been examined. Selenium ions had a potent inhibitory effect on the inactivation process for PGE2 and PGF2 alpha. Simultaneously, the levels of PGE2 and PGF2 alpha were increased. These results suggest that selenium ions have the potential to increase the levels of biologically active PGs in gastric mucosa by preventing their inactivation and that this effect may represent some pharmacological action of selenium ions.

Animals↗
PubMed1990

Medroxyprogesterone acetate binding sites in human endometrium and endometrial cancer.

Medroxyprogesterone acetate (MPA) binding sites in both human normal endometrium and endometrial carcinoma were identified and characterized by sucrose gradient centrifugation. These binding components were divided into two classes by saturation analysis, one with high affinity and low capacity and the other with low affinity and high capacity. The concentrations of low-affinity binding sites for MPA in endometrial carcinoma were higher than those in normal endometrium (p less than 0.01). By sucrose gradient centrifugation, 4S and 8S components were observed in both high- and low-affinity binding sites of normal endometrium. These components were moved to 4S by the addition of salt. However, in endometrial carcinoma, low-affinity binding sites were displayed at about 4S under either low- or high-salt conditions. High-affinity binding sites in endometrial carcinoma had the same sedimentation patterns as in normal endometrium. An obvious difference between normal endometrium and endometrial cancer was observed in low-affinity binding sites. Our results on the binding sites for MPA suggest that low-affinity binding sites may be related to the response of endometrial cancer to high-dose MPA treatment.

Binding Sites↗