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Biomedical subjects

Y Hiasa

Publications and source records attributed to Y Hiasa.

At least 73 records · Page 4Linked to original sources
PubMed1995

Immunohistochemical study of glutathione S-transferase-pi in meningiomas.

Immunostaining for glutathione S-transferase-pi was investigated in various subtypes of meningioma for the purpose of biological characterization. Specimens included five normal meninges and 25 meningiomas (10 meningothelial type, 6 fibrous type, 5 transitional type, 3 microcystic type, and 1 secretory type). In the meningothelial type, most cells showed strongly positive staining. In the fibrous type, all cells were negative. In the transitional type, only the meningothelial components were positive. In the microcystic type, meningothelial cell clusters and arachnoid trabecular cells were positive. In the secretory type, the meningothelial components and the pseudopsammoma-body-producing cells were positive. These results suggest that the meningothelial type and the fibrous type have a different basis of development and biological features. The results also suggest that arachnoid trabecular cells and meningothelial cells share the same origin, and that the arachnoid trabecular cells serve as supportive cells and as cells which detoxify harmful substances in the subarachnoid space. The pseudopsammoma-body-producing cells in the secretory type represent the outcome of epithelial differentiation of meningothelial cells with their biological character being preserved.

Culture Techniques↗
PubMed1995

[Initial and short-term results of percutaneous transluminal coronary angioplasty in patients over 70 years old: recent improvements in effectiveness].

Elderly patients have a higher incidence of procedure-related complications and recurrent angina after percutaneous transluminal coronary angioplasty (PTCA). However, early success rates seem to have improved. To determine whether outcome of PTCA in the elderly has changed recently, we compared initial results and short-term outcome in patients over 70 years old in two groups; 64 patients with 70 PTCA lesions who underwent first elective PTCA in 1982-1989 (early group) and 140 patients with 153 PTCA lesions in 1990-1993 (late group). The mean age of the late group was significantly older than that of the early group (74 +/- 3 vs 73 +/- 2 years, p < 0.01). The two groups had similar clinical characteristics including sex, prior myocardial infarction and multivessel disease. The overall success rate of PTCA was significantly higher in the late group than in the early group (92.8% vs 82.8%, p < 0.05). The rate of abrupt closure was similar in the two groups (2.9% vs 2.6%). Major complications (procedural myocardial infarction, emergency bypass surgery, hospital death) occurred in 4.7% of the early group and in 3.6% of the late group. Angiographic restenosis occurred in 41.5% of the early group and in 33.6% of the late group. Cardiac events (cardiac death and/or myocardial infarction) occurred in 6.6% of the early group and in 1.5% of the late group (p = 0.06). The initial success rate of PTCA has improved in the elderly as well as younger patients (< 70; 92.8% vs 91.6%). We conclude that PTCA can be performed with high initial success and satisfactory short-term outcome in patients over 70 years old.

Aged↗
PubMed1995

Intratumor cellular heterogeneity and alterations in ras oncogene and p53 tumor suppressor gene in human prostate carcinoma.

To assess the potential role of ras oncogene activation and p53 tumor suppressor gene mutations in the development of human prostate carcinoma, nine cases of histologically heterogeneous prostate tumors obtained from total prostatectomies were probed for these specific events. Each tumor was divided into 5 to 10 areas according to different growth or histological patterns. Targeted DNA sequences coding for ras and p53 were amplified by the polymerase chain reaction, analyzed by single-strand conformational polymorphisms, and confirmed by direct DNA sequencing. Point mutations of the ras gene were found in three of the nine tumors. Two contained K-ras codon 13 and H-ras codon 61 mutations, found in only one and three areas of each lesion, respectively. The third tumor contained two different point mutations in K-ras codons 13 and 61 in different foci of the sample. Loss of heterozygosity at the polymorphic codon 72 in the p53 gene was detected in two of four informative cases (50%) showing fragment cleavage by restriction fragment length polymorphism analysis. Mutations in p53, missense transversions, single base insertions, and two base deletions were also detected in three tumors. The present results reveal mutated ras and p53 occasionally occurring in small foci of the tumor and that genetic mutations in p53, as opposed to those in ras, are more closely associated with invasive growth of heterogeneous prostate carcinoma.

Carcinoma↗
PubMed1995

[Efficacy and safety of percutaneous transluminal coronary angioplasty of other coronary arteries in patients with chronic total occlusion of the left anterior descending artery].

The acute and long-term outcomes of percutaneous transluminal coronary angioplasty (PTCA) of the right coronary artery (RCA) or left circumflex branch (LCS) in patients with chronic occlusion of the left anterior descending branch (LAD) (group A) were compared with those of sex and age matched patients undergoing PTCA of the RCA or LCX with a normal LAD (group B). Before the procedure, group A had more frequent prior myocardial infarction (96% vs 33%, p < 0.001), and a lower left ventricular ejection fraction (LVEF) (49 +/- 14% vs 71 +/- 13%, p < 0.001). The acute results were similar in the two groups with respect to primary success (group A 90%, group B 91%) and major complications (group A 6%, group B 2%). At 3 months, the rate of restenosis was 33% in group A and 27% in group B. In group A, LVEF increased significantly in patients without restenosis (53 +/- 11% vs 62 +/- 11%, p < 0.01). At long-term follow-up, group A had higher rates of persistent angina but there was no difference in outcome between the two groups. In patients with chronic total occlusion of LAD, PTCA for RCA or LCX can be performed with a low complication rate and provides a significant improvement in LVEF at 3 months in the absence of restenosis. However, at short-term follow-up, these patients have a greater incidence of persistent angina.

Adult↗
PubMed1995

[Newly developed detection system for serum Helicobacter pylori antibodies using ELISA and its clinical significance].

Using ELISA, a specific and sensitive system that detects serum immunoglobulin G antibodies against all soluble antigens of Helicobacter pylori (Hp) has been developed. This system is used at three different concentrations of Hp antigens coated on the solid phase of the ELISA. Anti-Hp antibodies were judged positive when the difference in the ELISA values between high and middle or middle and low concentrations of antigen were over the specific values. For the ELISA system, called the three point antigen method, sensitivity and specificity of urease activity were 86.9% and 70.8%, respectively. Positive rate for antibodies to serum Helicobacter pylori in dyspeptic patients was higher than that in healthy subjects.

Antibodies, Bacterial↗
PubMed1995

[Immunohistochemical study of the endomyocardial biopsy of systemic lupus erythematosus].

The mechanisms of cardiac involvement in systemic lupus erythematosus (SLE) were studied using immunohistochemical staining of endomyocardial biopsy specimens from 14 patients with SLE and normal coronary arteriograms. All 14 specimens showed mild interstitial edema, 11 showed mild cardiac fibrosis, and another two cases showed moderate cardiac fibrosis with myocardial derangements. Four specimens showed moderate cell infiltration in the interstitium. Area of fibrosis, diameter of myocardium and area of interstitial edema were increased in the SLE patients compared to the control cases. Immunofluorescence showed IgG and fibrinogen deposition in the membrane of cardiac myocytes and in the interstitium. Immunohistochemistry found no B lymphocytes in any of the seven SLE cases. T lymphocytes were observed in all seven SLE cases, and OKT 8 lymphocytes were increased significantly in the interstitial tissue as compared with OKT 4 lymphocytes. At endomyocardial biopsy, all 14 patients were receiving corticosteroid therapy and had low activity disease. The results suggest that cardiac tissue damage was associated with immunological abnormalities and might progress silently under conditions in which the disease activity was suppressed by corticosteroid therapy.

Adult↗
PubMed1994

Expression of the estrogen receptor in human thyroid neoplasms.

The expression and quantitation of the estrogen receptor (ER) in human thyroid tumors were examined by biochemical, immunohistochemical, and reverse transcriptase-polymerase chain reaction (RT-PCR) techniques. For this study, neoplasms, adenomatous goiters and adjacent normal thyroid tissues were obtained from 35 patients which included 10 cases of papillary carcinomas, 17 cases of adenomas and 8 cases of adenomatous goiters. Regardless of the histopathological subtype, ER was detected in 19% (5/27) of the neoplastic tissues with the mean value of ER content of 5.0 +/- 1.3 fmol/mg protein and the mean Kd value of 0.38 +/- 0.28 nM. ER was also detected, but at a lower concentration (2.8 +/- 1.6 fmol/mg protein), in the surrounding normal tissues. There was no significant difference between the neoplasms and adenomatous goiters with respect to the incidence of ER positivity and ER content. Furthermore, ER-positive specimens, as determined by both biochemical and immunohistochemical techniques, also showed the expression of ER mRNA detected by RT-PCR method. These results demonstrate that both ER mRNA as well as ER protein are expressed in thyroid neoplasms. This suggests the possibility that estrogen may affect the tumorigenesis or the progression of some thyroid neoplasms.

Adenoma↗
PubMed1994

Ki-ras oncogene activation in transplantable rat thyroid carcinoma induced by N-bis(2-hydroxypropyl)nitrosamine.

We have established 17 transplantable rat thyroid carcinoma cell lines from primary thyroid tumors of rats induced by N-bis(2-hydroxypropyl)nitrosamine (DHPN) (Cancer Res. (1993) 53, 4408-4412). The present study was designed to evaluate point mutations in the murine c-Ki-ras gene of these carcinoma cell lines. Using PCR amplification and direct sequencing, we found that the activated form of the Ki-ras oncogene was present in 4 (23%) of a total of 17 cell lines, all the Ki-ras gene mutations being GC-->AT transitions. In three of the cell lines, the mutations occurred in codon 12 (GTP-binding domain), and in the remaining one the first nucleotide of codon 63 was affected. Histologically, three of the carcinomas with Ki-ras mutation were diagnosed as well-differentiated carcinomas, and the other as poorly differentiated carcinoma. Mutations of the ras gene are relatively uncommon in tumors of these histological types. From these experimental results, we suggest that the mutation induced by DHPN is due to damage to guanine in cellular DNA. In addition, Ki-ras activation may play an important role in the initiation of thyroid carcinogenesis.

Animals↗
PubMed1994

Restenosis after successful emergency coronary angioplasty for acute myocardial infarction: comparison with elective angioplasty.

We investigated the initial and late restenosis rate after successful emergency coronary angioplasty in 64 patients with acute myocardial infarction, and compared these results with those of 100 patients (110 lesions) who had successful angioplasty on an elective basis. The majority of the baseline clinical and angiographic variables were similar in the myocardial infarction and elective groups. The restenosis rate at 1 month was high in patients undergoing emergency angioplasty for acute myocardial infarction (23 vs. 12%). At 3-6 months, the angiographic restenosis rate was low for the infarction group (26 vs. 37%). The overall restenosis rate was similar in the infarction and elective groups (39 vs. 40%). Lesion regression after coronary angioplasty was more frequent in the infarction than in the elective angioplasty group (27 vs. 14%, P < 0.05). These findings suggest that considering the high restenosis rate at 1 month and the lower, but still 20% or more, rate at 3-6 months, a follow-up angiography should be performed both prior to discharge and at 3-6 months after the procedure, in patients with acute myocardial infarction.

Aged↗
PubMed1994

Primary plasmacytoma of the thyroid: a case report and comparative literature study between Western nations and Japan.

A 52 year old man presented with primary thyroid plasmacytoma. The patient was initially followed up for thyroid dysfunction. The histological examination of the removed thyroid revealed a proliferation of mature and immature plasma cells indicative of plasmacytoma with Hashimoto's disease. After radiotherapy (40 Gy) to the neck following right hemi-thyroidectomy, the patient is currently alive and well 3 years after diagnosis without any evidence of tumor. The immunohistological examination of the removed thyroid showed monoclonality for immunoglobulin G-Kappa light chains. Sixty-six literature cases of primary thyroid plasmacytoma were reviewed and comparison of the clinical and histological characteristics between Japanese and Western cases noted. The incidence of the patients with antithyroid antibody was significantly lower (P < 0.01) in Western patients (42.9%) than in Japanese patients (87.5%). The higher incidence of thyroid dysfunction and Hashimoto's disease in Japan in comparison with Western nations was well reflected in the incidence of antithyroid antibody.

Autoantibodies↗
PubMed1994

Progressive activity in latent prostate carcinoma defined by argyrophilic staining of the nucleolar organizer regions (AgNOR).

Argyrophilic staining of the nucleolar organizer regions (AgNOR) was studied in 30 cases of benign prostatic hyperplasias (BPH), 17 cases of latent prostate carcinomas, 50 cases of clinical carcinomas and seven cases of metastatic lesions from prostate carcinomas. The criteria for these comparisons were the number of positive-staining dots per nucleus, the area of the dots, and a relative score determined by multiplying the number of positive-staining dots in the nuclei by the areas of the dots. Overall, there were no significant differences in these three parameters between BPH and latent carcinomas. Among latent carcinomas, however, significantly higher AgNOR scores were observed for infiltrative lesions than for non-infiltrative lesions. AgNOR dot number, area and score increased as tumors became less differentiated, with no significant differences detected in metastatic versus non-metastatic carcinomas. These results suggest that some latent tumors are similar in biological behavior, such as cell proliferation, to clinical carcinoma.

Carcinoma↗
PubMed1994

Percutaneous hot saline injection therapy for hepatic tumors: an alternative to percutaneous ethanol injection therapy.

PURPOSE: To evaluate the usefulness of percutaneous hot saline injection therapy (PSIT) in the treatment of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Twenty patients with HCC (23 nodules) underwent PSIT. Mean tumor diameter was < or = 30 mm. PSIT was performed by injecting hot saline into the HCC. The therapeutic effect of PSIT was evaluated with computed tomography, angiography, measurement of alpha-fetoprotein levels, and histopathologic examination of needle biopsy and resected specimens. RESULTS: No complications were encountered, and a therapeutic effect was obtained in all cases. When the injected material cools, it becomes physiologic saline making it possible to inject relatively large volumes in a single session. CONCLUSION: PSIT has promise as a form of curative local therapy for small HCCs and is expected to exert a safe and favorable therapeutic effect on large HCCs as well.

Aged↗
PubMed1993

Establishment of estrogen receptor-positive transplantable rat thyroid tumor cell lines in vivo.

We established 17 transplantable rat thyroid tumor cell lines from the primary thyroid tumor of rats induced by N-bis(2-hydroxypropyl)nitrosamine. Among the 17 tumor cell lines established, only two of them (D1 and G1) were estrogen receptor (ER) positive. These two cell lines were characterized with respect to transplantability, histological features, ER contents and cellular localization, and expression of ER message. The ER contents, determined by dextran-coated charcoal assay, were 13.3 and 20.7 fmol/mg protein for D1 and G1 cell lines, respectively. Scatchard plot analysis indicates that the dissociation constants (Kd) were 0.17 and 0.4 nM, respectively, for D1 and G1 cell lines. Sucrose density centrifugation analysis detected a hormone-receptor complex which sedimented at the 4S region, characteristic for ER. Immunohistological staining revealed that the ER was localized in the nuclei. The presence of ER in D1 and G1 cell lines was further confirmed by reverse transcriptase-polymerase chain reaction to detect the ER mRNA. These results demonstrated that ER is expressed in some thyroid tumors. The ER-positive transplantable tumor cell lines are useful for studying the direct effect of estrogen on thyroid tumors in vitro and in vivo.

Animals↗
PubMed1993

[Percutaneous hot water injection therapy (PHoT) for hepatic tumors: a clinical study].

Percutaneous ethanol injection therapy (PEIT) has become widely used in the treatment of HCC. However, the indications for this method are limited by the toxicity of ethanol itself. Against this background, the authors turned their attention to the heat coagulation necrosis effect induced by boiled physiological saline (hot water) and devised percutaneous hot water injection therapy (PHoT) as a new local treatment method. PHoT was performed a total of 41 times in 13 patients (16 nodules) with HCCs measuring < or = 3 cm. Changes in AFP values, CT findings, angiographic findings before and after treatment, and histopathological findings of needle biopsy or resected specimen were investigated. AFP values decreased in all of the seven patients who initially showed high values. On CT, all lesions receiving PHoT became hypodense, with this change thought to indicate necrosis. Disappearance of the tumor stain was confirmed in the four patients in whom follow-up angiography was performed. In the six patients in whom needle biopsy was performed, disappearance and scaring of tumor cells were observed, while in the one patient in whom the tumor was resected, complete necrosis of the tumor was confirmed. PHoT, despite a small number of punctures, shows good anti-tumor effects, and has promise not only as a curative local treatment method for small HCCs but also in combination with TAE for large HCCs.

Aged↗
PubMed1993

Expression of nm23-H1 and nm23-H2 proteins in prostate carcinoma.

The nm23 gene products/nucleoside diphosphate (NDP) kinase expression in prostate carcinomas and benign hyperplasias was evaluated immunohistochemically. Monoclonal antibodies against nm23-H1 and nm23-H2 proteins were prepared using the corresponding proteins fused with glutathione S-transferase as immunogens. Of the 80 cases of nonmetastatic prostate carcinoma examined, 74% (59/80) and 60% (48/80) were immunoreactive for nm23-H1 or nm23-H2 protein, respectively. Negative staining for nm23-H1 occurred in 83% of metastatic lesions, while 34% were negative for nm23-H2. All primary tumors corresponding to the metastases examined showed positive immunostaining for nm23-H1, indicating an inverse relationship between expression of this protein and metastatic status. nm23-H2 protein was detected in 83% of primary tumors and its expression appeared to be significantly correlated to the degree of histological differentiation. In contrast, all cases of benign prostatic hyperplasia showed elevated levels of both nm23-H1 and nm23-H2 expression. These data suggest that the nm23/NDP kinase may play a role in suppressing the expression of malignant potential in prostate carcinomas.

Adenocarcinoma↗
PubMed1993

Inhibitory effect of potassium citrate on rat renal tumors induced by N-ethyl-N-hydroxyethylnitrosamine followed by potassium dibasic phosphate.

Potassium dibasic phosphate (PDP) was administered at a concentration of 10% by weight in basal diet to unilaterally nephrectomized Wistar rats previously given 1000 ppm N-ethyl-N-hydroxyethyl-nitrosamine (EHEN) in the diet for 2 weeks. To study the effect of alkalinization on renal mineralization, some animals concomitantly received 5% potassium citrate (PC). Feeding PDP alone promoted adenomatous hyperplasias, which were regarded as preneoplastic lesions, as well as renal cell tumors in EHEN-initiated rats, whereas the addition of PC to PDP diets reduced the promoting effect. Histopathology, serum biochemistry and urinalysis indicated retardation of renal calcium crystallization by PC. Two other phosphate salts, sodium phosphate (SP) and calcium phosphate (CP), were also administered. SP showed a slight promoting effect on adenomatous hyperplasias and a 2-fold increase in the yield of renal cell tumors, while CP induced a clear reduction of both lesions, over EHEN alone. The promoting effects of both PDP and SP and the inhibitory effect of PC were somewhat correlated to 5-bromo-2'-deoxyuridine labeling indices, the degree of nephropathy, and mineralization in the kidney. Immunohistochemically, the nephropathy induced by phosphate salts was not linked to alpha 2u-globulin. A pathogenesis for renal carcinogenesis is suggested in which nephropathy associated with mineralization enhances the development of renal cell tumors.

Alpha-Globulins↗
PubMed1993

Clinical studies of de novo aneurysms.

Although multiple cerebral aneurysms ae well recognized, a new aneurysm has only rarely been documented after successful treatment for an aneurysm elsewhere. In our consecutive series of 986 patients with intracranial saccular arterial aneurysm collected from 1975 to 1990, nine patients who had previously unverified (hence, de novo) intracranial aneurysms and ruptures at intervals of 4 to 7.5 years after clipping of an initial aneurysm are presented here. All nine had undergone successful treatment of a previous aneurysm; preoperative and postoperative angiography showed not only successful clipping of the first aneurysm but also no incidence of multiple aneurysms. These patients had suffered from hypertension before their second admission. Seven of the nine patients were treated surgically. All patients had experienced angiographical or symptomatic vasospasm after the first subarachnoid hemorrhage. In the second admission however, seven patients who underwent the surgery for a new aneurysm suffered from no vasospasm in spite of the prominent second subarachnoid hemorrhage. Two of the nine patients died of primary brain damage due to the hemorrhage and underwent necropsy. A histological study of a new aneurysm demonstrated the same findings as that of a usual saccular aneurysm. This clinical study of our patients suggests that it is important to control blood pressure for protection against a new aneurysm formation.

Adult↗