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Biomedical subjects

Y Mizukami

Publications and source records attributed to Y Mizukami.

At least 163 records · Page 9Linked to original sources
PubMed1992

Wide resection with latissimus dorsi muscle transposition in breast conserving surgery.

In this study we evaluated whether the immediate transposition of the latissimus dorsi muscle (LDM) improves breast appearance and patient satisfaction after quadrantectomy. Twenty-three patients (transposed group) had the transposition of LDM immediately after quadrantectomy, but eight patients (non-transposed group) had quadrantectomy alone. For evaluation, breast size was classified as small (A or B cup) and large (C or D cup). Consequently, the cosmetic result was evaluated as excellent in 73% of the patients with transposed small breasts, but in only 25% of the patients with non-transposed small breasts and by none of the patients with transposed large breasts. On the other hand, all patients with transposed small breasts reported that they are satisfied with their operation, as opposed to 88% of the patients with transposed large breasts and 63% of the patients with transposed large breasts and 63% of the patients with non-transposed small breasts. It was concluded therefore, that the transposition of LDM is useful in correcting post-quadrantectomy breast deformity, especially in patients with small breasts.

Adult↗
PubMed1992

Carcinoma of the thyroid at a young age--a review of 23 patients.

Twenty-three children and adolescents with thyroid carcinoma who were 20 years old or younger at the time of initial treatment were followed for a mean time of 9.5 years. Of the tumours, 21 were papillary and two follicular carcinomas. The majority (91%) of the 23 cases showed extra-thyroidal extension of the tumour. An association with chronic thyroiditis was observed in 30% of the cases. There was no history of irradiation of the head and neck in any patients. Relapse occurred in eight patients, lung metastases in two and local recurrences in six; one patient died from lung metastases 3 months after initial treatment. Male patients, advanced stage of tumour, less differentiated histological features and DNA aneuploidy were associated with a higher frequency of relapse. The prognosis of thyroid carcinomas in children and adolescents is not so good as is generally believed.

Adenocarcinoma↗
PubMed1992

Papillary thyroid carcinoma in Kanazawa, Japan: prognostic significance of histological subtypes.

A retrospective analysis of 183 papillary thyroid carcinomas was made in order to assess the prognostic factors related to survival. The following factors were found to adversely affect the prognosis: trabecular subtype of papillary carcinoma, the extent of the primary tumour, regional lymph node involvement, the presence of distant metastases, old age, male sex and the extent of the neck dissection. The presence of the follicular variant of papillary carcinoma and the extent of the thyroidectomy did not influence the prognosis. The trabecular subtype of papillary carcinoma is characterized by a trabecular or solid arrangement of follicular cells with nuclei of ground-glass appearance. Univariate and multivariate analysis indicated that patients with this type of thyroid tumour had a poorer prognosis than those with the well-differentiated or follicular variants of papillary carcinoma. In our opinion the trabecular subtype of papillary carcinoma should be included as a separate entity in the WHO classification of thyroid tumours.

Adolescent↗
PubMed1992

Histologic changes in Graves' thyroid gland after 131I therapy for hyperthyroidism.

The effect of 131I therapy was examined in 13 thyroid glands affected by Graves' disease 3 to 29 years after irradiation for hyperthyroidism. All of the patients had clinically palpable thyroid nodules. Two patients were in a latent hypothyroid, 6 in a euthyroid and 5 in a hyperthyroid state. The microscopic changes in the thyroids showed a pattern of multiple adenomatous nodules with cystic changes, marked oxyphilic cell changes with nuclear atypism and various degrees of chronic thyroiditis. Immunohistochemical staining for TG and T4 was negative to mildly positive in these oxyphilic cells and entirely negative for EGF and CEA. The DNA ploidy pattern was diploid pattern in 6 cases. One papillary-type microcarcinoma occurred, but there was no evidence of a relationship between the tumor and the irradiation. The pathologic findings in Graves' thyroid gland after 131I therapy are not specific, but pathologists should differentiate this lesion from adenomatous goiter, which occurs with no apparent cause, or from thyroid carcinoma because of the marked nuclear atypism of this lesion.

Adult↗
PubMed1992

Effects of switching from a high-fat diet to a low-fat diet on tumor proliferation and cell kinetics of 7,12-dimethylbenz(a)anthracene-induced mammary carcinoma in rats.

We investigated the stimulatory effect of a high-fat diet on tumorigenesis, tumor proliferation and cell kinetics of 7,12-dimethylbenz(a)anthracene-induced mammary carcinomas in Sprague-Dawley rats, and sought to determine whether switching the animals from a high-fat diet to a low-fat diet would suppress tumor proliferation and cell kinetics. The high-fat diet significantly stimulated tumorigenesis, tumor proliferation and cell kinetics. After the animals were switched from the high-fat diet to the low-fat diet, however, tumor growth decreased, the BrdUrd labeling indices of tumors significantly decreased, and the potential doubling times of tumors significantly increased. Therefore, switching from a high-fat diet to a low-fat diet may improve the prognosis of breast cancer.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1992

Metabolic fate of [14C]triglyceride-entrapped lactosylceramide-bearing liposomes after intravenous injection into mouse.

We investigated the distribution and fate of liposomes after their intravenous injection into a mouse. Liposomes were composed of dimyristoylphosphatidylcholine, cholesterol and dicetylphosphate (7:2:1, molar ratio) with or without lactosylceramide. They were characterized as small unilamellar vesicles, approximately 100 nm in diameter, using gel-exclusion chromatography on a Sephacryl S-1000, freeze-fracture electron microscope and dynamic light scattering method. Liposomes were very stable in serum as seen by the results of leakage of the entrapped marker and electrophoresis experiments. We demonstrated that liposomes were internalized by way of an endocytotic process via coated vesicles detected in the electron microscope. The increase in liver uptake of lactosylceramide-bearing liposomes was mostly accounted for by enhanced uptake in the parenchymal cells, while uptake by non-parenchymal cells was only slightly increased. This observation supported the notion that a galactose-specific receptor was involved in liver uptake of lactosylceramide liposomes. The lactosylceramide-bearing liposomes were preferentially recovered in the liver and were found to first be predominantly localized in the mitochondria-lysosomal fraction. They were then decomposed by lysosomal enzymes, and the hydrolyzed components were reincorporated into membrane phospholipids in the microsomal fraction. At the same time, a rapid and reversible exchange of phosphatidylcholine between microsomes and mitochondria was demonstrated.

Absorption↗
PubMed1992

Fluorescent probe-labeled lipid microsphere uptake by human endothelial cells: a flow cytometric study.

Lipid microspheres have been used as carriers of drugs such as prostaglandin E1 (lipo-PGE1) and corticosteroid (liposteroid). Lipo-PGE1 is used for the treatment of chronic arterial occlusive diseases because its activity is far greater than that of free PGE1 in vivo. To verify the fact that the drug carriers, lipid microspheres, are preferentially taken up by endothelial cells, we labeled lipid microspheres with a fluorescent probe, DiI (DiI-LM), and observed them in some in vitro models. Stoichiometric fluorescence was obtainable, and the fluorescence was stable between pH 3.3 and pH 8.9. Human umbilical vein endothelial cells and cells of a human endothelial cell line, ECV304, showed increased uptake of DiI-LM, 81% and 61%, respectively. In contrast, uptakes were less than 7% in human skin fibroblasts, 3T3 cells, and human neutrophils. Prominent perinuclear fluorescence was also observed in endothelial cells by fluorescence microscopy. DiI-LM and flow cytometric analysis will be useful for studies to elucidate the precise mechanism of the selective accumulation of lipid microspheres by cells in blood vessel walls.

Carbocyanines↗
PubMed1992

Primary extramedullary plasmacytoma of the lung.

A case with primary plasmacytoma of the lung is described. The patient, a 55-year-old Japanese female, who simultaneously had a pulmonary plasmacytoma and bladder carcinoma. The bladder tumor was treated with transurethral resection. Pathologically, the bladder tumor was a non-invasive, papillary transitional cell carcinoma, grade II. The lung tumor was located in the right upper lobe and upper lobectomy was performed. The tumor measured 2.8 x 2.7 x 2.0 cm and had a white-yellowish cut surface. Histologic, electron microscopic and immunohistochemical examinations of the lung tumor revealed monoclonal proliferation of plasma cells (IgA, lambda light chain). There was no evidence of multiple myeloma.

Female↗
PubMed1992

The cellular infiltrate in the liver of patients with fulminant hepatitis: analysis of paraffin-embedded tissue sections.

Intrahepatic infiltrate from 18 patients who died of fulminant hepatitis, was analyzed by an immunohistochemical method using formalin-fixed, paraffin-embedded liver sections and monoclonal antibodies. Inflammatory cells were characteristically located in the portal and periportal areas adjoining resting hepatocytes, but were infrequently found in the perivenular areas where hemorrhagic hepatocyte necrosis predominated. In the inflammatory infiltrate, T cells were the most predominant cell type, composing about two-thirds of the total hepatic infiltrate, followed by lysozyme-positive macrophages which composed about one-third of the total hepatic infiltrate, irrespective of the etiology of the fulminant hepatitis. On the other hand, B cells made up less than 2% in all cases, and plasma cells were also few, less than 2% in 12 of 18 cases. Furthermore, an enhanced display of beta 2-microglobulin on hepatocyte membranes was demonstrated in all cases with remaining hepatocytes, indicating an increased expression of class I MHC antigens on these cells. These results suggest that T cells may play an important role in the pathogenesis of the portal and periportal lesions of fulminant hepatitis, probably with a help of MHC class I antigens on hepatocytes, while hemorrhagic necrosis of hepatocytes around the central veins may be caused by a different mechanism, most likely a circulatory disturbance secondary to cell-mediated immune reactions in the periportal areas.

Acute Disease↗
PubMed1992

Seven patients with plasma cell granuloma (inflammatory pseudotumor) of the lung, including two with intrabronchial growth: an immunohistochemical and electron microscopic study.

Seven patients (mean age, 50.7 +/- 20.4 years; range 21-77) with plasma cell granuloma (PCG) of the lung are reported. Cough and sputum were the most common presenting symptoms, followed by fever. Elevated erythrocyte sedimentation rate and serum C-reactive protein levels were found in all patients tested. Radiologically, five cases presented as solitary, well-circumscribed masses and two as ill-defined, pneumonia-like densities. One showed focal calcification. No predilection of occurrence was observed in either lobe of the lung. Histologically, the lesions consisted of a proliferation of mature plasma cells and reticulo-endothelial cells supported by a stroma of granulation tissue, with varying degrees of myxoid change or collagenization. Angioinvasion within the lesion was observed in 4 of the 7 cases. Immunohistochemical staining revealed the IgG-predominant polyclonal nature of the plasma cells, indicating a reactive inflammatory process rather than a neoplastic one. Electron microscopy confirmed the benign nature of the plasma cells with fibroblast and myofibroblast proliferation admixed with that of other inflammatory cells.

Adult↗
PubMed1992

Effects of high and low dietary fat and indomethacin on tumour growth, hormone receptor status and growth factor expression in DMBA-induced rat breast cancer.

The effects of high and low dietary fat (20% vs. 0.5% corn oil), and of the prostaglandin synthetase inhibitor indomethacin (0.005% w/w), on tumour incidence, tumour growth, hormone-receptor status and growth-factor expression were examined in dimethylbenzanthracene (DMBA)-induced rat breast cancer. The high dietary-fat group showed a significantly higher tumour incidence, larger tumour size and larger number of bromodeoxyuridine(BrdU)-positive cells of tumours as compared with those in the low dietary-fat group. Indomethacin reduced tumour incidence significantly, but conversely increased the tumour size and the number of BrdU-positive cells in both the high and the low dietary-fat groups. No significant difference was noted in the hormone-receptor status of the tumours. Growth factors (TGF-alpha and IGF-II) were somewhat highly expressed in the high dietary-fat group as compared with the low dietary-fat group, but indomethacin rather reduced the growth-factor expression. It is concluded that high dietary fat stimulates tumour incidence and tumour proliferation, while indomethacin has dual effects: a stimulating effect on tumour proliferation, but an inhibiting effect on tumour incidence. It is also suggested that hormone-receptor status and growth-factor expression do not play an important role in their stimulating effects on tumour proliferation.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1992

An autonomously functioning thyroid carcinoma associated with euthyroid Graves' disease.

A 39-yr-old man with an autonomously functioning thyroid carcinoma is presented. Only 17 similar cases have been reported in the literature. The patient had unilateral Graves' ophthalmopathy. He was euthyroid as reflected by normal TSH concentration, whereas the results of a T3 suppression test established the presence of autonomous thyroid function. A thyroid scan with (123)I revealed a hot nodule corresponding to the location of a papillary carcinoma and remained substantially unchanged after T3 administration. The hyperfunction of the carcinoma itself was clearly confirmed by the intense concentration of (131)I within the tumor on microautoradiograms. While a hot nodule on radioiodine scan is unlikely to be malignant, the possibility of carcinoma should not be overlooked.

Adult↗
PubMed1992

[Prognostic significance of internal mammary lymph node metastases in breast cancer patients].

Examination was made of clinical, histological and biological prognostic factors in 207 patients with invasive breast cancer, and determination was made as to whether variable prognostic factors, especially internal mammary lymph node metastases, would serve as a basis for the prognosis of breast cancer. In a univariate study, overall survival was significantly corrected with tumor size, axillary lymph node status, axillary and internal mammary lymph node metastases and DNA ploidy status. In a multivariate study, however, only axillary and internal mammary lymph node metastases were recognized as important, and independent prognostic factors on survival. Neither axillary lymph node status nor DNA ploidy status appeared an important prognostic factor. Axillary and internal mammary lymph node metastases could not be predicted from their clinical assessment. Only axillary lymph node dissection and biopsy of first and second intercostal spaces were concluded to be useful for accurately indicating the status of these lymph nodes.

Adult↗
PubMed1991

Reappraisal of internal mammary node metastases as a prognostic factor in patients with breast cancer.

Clinical, histologic, and biologic prognostic factors were examined in 144 patients with invasive breast cancer. It was determined whether variable prognostic factors, especially internal mammary lymph node metastases, would serve as a basis for the prognosis of breast cancer. In a univariate study, overall survival was significantly correlated with tumor size, axillary lymph node status, axillary and internal mammary lymph node metastases, and DNA ploidy status. Especially among patients with one to three positive axillary nodes, survival in case of internal mammary involvement were significantly lower than without internal mammary involvement. In a multivariate study, only axillary and internal mammary lymph node metastases were recognized as important, independent prognostic factors of survival, but neither axillary lymph node status nor DNA ploidy status appeared as important prognostic factors. It was concluded that internal mammary lymph node metastases is additional prognostic factor, especially in patients with one to three positive axillary nodes. Because axillary and internal mammary lymph node metastases could not be predicted from their clinical assessment, axillary lymph node dissection and biopsy of internal mammary nodes may be a useful staging procedure for these patients.

Adenocarcinoma, Mucinous↗
PubMed1991

Effects of the prostaglandin synthetase inhibitor indomethacin on tumorigenesis, tumor proliferation, cell kinetics, and receptor contents of 7,12-dimethylbenz(a)anthracene-induced mammary carcinoma in Sprague-Dawley rats fed a high- or low-fat diet.

The effects of indomethacin on tumorigenesis, tumor proliferation, cell kinetics, and receptor content of 7,12-dimethylbenz(a)anthracene-induced mammary carcinoma have been examined in female Sprague-Dawley rats. The rats were fed either a high-fat (20% corn oil) or low-fat (0.5% corn oil) diet with or without 0.005% indomethacin starting 7 days after intragastric administration of a single dose of 5 mg 7,12-dimethylbenz(a)anthracene. The results demonstrated that indomethacin completely blocked the stimulatory effect of fat on tumorigenesis, as demonstrated by a decreased tumor incidence, a decreased number of tumors per group, and an increased latency. Contrary to what had been expected, however, indomethacin promoted tumor proliferation in both the high- and low-fat diet groups, as evidenced by an increased tumor size, an increased bromodeoxyuridine-labeling index, and a decreased potential tumor-doubling time. No significant difference in either the estrogen receptor or progesterone receptor content of the tumor was noted. It can be concluded, therefore, that indomethacin significantly reduced tumorigenesis in the high-fat diet group but significantly promoted tumor proliferation in both the high- and low-fat diet groups.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1991

Estrogen and estrogen receptors in thyroid carcinomas.

Thyroid tissues, composed of normal thyroid (10 cases), Graves' thyroid (4), and papillary carcinoma (10), were measured for the presence of receptors for estrogen (ER) using an enzyme-immunoassay method. The mean value of ER in papillary carcinoma tissues (4.0 +/- 3.6 fmol/mg protein) was higher than that in normal thyroid tissues (0.8 +/- 0.4 fmol/mg protein) or that in Graves' thyroids (2.6 +/- 0.9 fmol/mg protein). In 10 papillary carcinomas, 3 were from male patients and 7 were from females. The mean value of ER in the tumors from male patients (7.2 +/- 5.1 fmol/mg protein) was higher than that from female patients (2.6 +/- 1.7 fmol/mg protein). Another set of 100 thyroid tissues from normal (20 cases), Graves' disease (10), follicular adenoma (8), and papillary carcinoma (62) was also examined for the presence of estradiol (E2) using an immunohistochemical method on formalin-fixed paraffin-embedded sections. E2-positive tissues were found in 4 (40%) of 10 Graves' thyroids, 4 (50%) of 8 adenomas, and 47 (76%) of 62 papillary carcinomas. In 62 papillary carcinomas, E2-positive tissues were found in 37 (73%) of 51 female patients and 10 (91%) of 11 male patients. In relation to relapse of the carcinomas, E2-positive carcinomas were found in 10 (71%) of 14 patients with relapse of the disease and in 14 (54%) of 26 patients with no relapse (the difference was not significant). The findings indicate that thyroid carcinomas may be estrogen-dependent, but no definite conclusions could be drawn between the biological behavior of the tumors and the E2-positivity.

Adenoma↗