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R Yatani

Publications and source records attributed to R Yatani.

At least 73 records · Page 4Linked to original sources
PubMed1994

Tenascin expression and postnatal development of the human prostate.

We investigated the distribution of tenascin during postnatal development of the human prostate. Monoclonal antibody specific to human tenascin was applied to paraffin sections by the avidin-biotin-complex method to examine its localization. Infantile prostates showed two distinct zones. The inner zone had sparse acini with fibromuscular bundles. The peripheral zone had similar acini and lighter stroma as compared with inner zone. Tenascin was found diffusely but weakly. The periglandular area occasionally showed immunoreactivity. The prostates from 9- to 13-year-old subjects had a morphology similar to that of the infantile gland. The difference was increased density of the acini. Immunoreactivity was low. In the prostates from 14- to 21-year-old subjects, the acini distribution was more crowded, and the epithelial lining had become taller in both zones. Tenascin distributed preferentially in the peripheral zone during this period. Simultaneously, the percent of glandular area in the peripheral zone rose abruptly. The dynamics of tenascin expression are closely associated with the development and maturation of the gland. The distribution of tenascin during the post-puberal period may suggest its participation in the preferential of prostatic carcinoma in the peripheral zone.

Adolescent↗
PubMed1994

[Gallbladder carcinoma: expression of the c-myc and ras-p-21 oncogene products].

The expression of c-myc and p-ras-21 oncogenes was studied using an immunohistochemical method with monoclonal antibodies in 126 samples of gallbladder carcinoma (103 primary tumors and 23 metastatic lesions). Twenty five gallbladder samples without tumor evidence were used as controls. C-myc oncoprotein was positive in one control sample and p-ras-21 oncoprotein was negative in all. Among primary carcinomas c-myc was positive in 9 (9%) and p-ras-21 in 4 (4%); among metastatic carcinomas c-myc was positive in 6 (26%, p = 0.03 vs primary carcinoma) and p-ras-21 in 11 (48%, p < 0.001 vs primary carcinoma). There was a non significant association between c-myc and p-ras-21 expression and degree of histological differentiation and level of tumoral infiltration. It is concluded that c-myc and p-ras-21 oncoprotein expression is observed in less than 10% of primary gallbladder carcinomas and that this expression is significantly higher in metastatic carcinomas. This may reflect an activation or overexpression of these oncogenes in metastatic cells.

Amino Acid Sequence↗
PubMed1993

Phosphorylation of a 62 kd porcine alpha-internexin, a newly identified intermediate filament protein.

A 62 kd protein was purified from the Triton-insoluble fraction of porcine brain white matter. This protein formed 10nm filaments, in vitro. The phosphorylation of the 62 kd protein by cAMP-dependent protein kinase caused electrophoretic mobility to shift to 66 kd on SDS-PAGE and a complete loss of the filament forming ability ensued. Amino acid sequences of four peptide fragments obtained from the 62 kd protein by lysylendopeptidase were identical with that of a 66 kd rat brain alpha-internexin. Amino acid analyses of the phosphopeptide fragment derived from phosphorylated porcine alpha-internexin revealed that the phosphorylation sites by cAMP-dependent protein kinase located in the amino-terminal head domain of this protein. These results strongly suggest that alpha-internexin polymerizes into 10nm filaments in vitro and that phosphorylation of the amino-terminal domain of alpha-internexin controls its polymerizability.

Amino Acid Sequence↗
PubMed1993

Mucous gland metaplasia of the prostate.

Mucous gland metaplasia of the prostate was observed in 11 of the 1,236 autopsy cases. The cells were characterized by plump cytoplasmic mucin and tiny nuclei that were basally oriented. They resembled Cowper's gland (bulbourethral gland) epithelium. The lesion was located randomly within the glands and was very small; only one was larger than 1 mm2. The cytoplasmic mucin was periodic-acid Schiff positive and immunohistochemically negative for prostate-specific antigen. Lectin binding profiles were different from those of normal prostatic glandular epithelium and also from those of Cowper's gland. The importance of recognizing mucous metaplasia lies in its differentiation from other lesions, especially from low-grade carcinoma.

Adult↗
PubMed1993

Proliferating cell nuclear antigen in gallbladder carcinoma.

Proliferating cell nuclear antigen (PCNA) expression was studied in 103 gallbladder carcinomas and 23 metastatic lesions as well as in 25 control non-neoplastic gallbladder specimens. Positive nuclear staining was observed in 88% of controls, in 92% of carcinomas and in 70% of metastases. The mean number of positive cells was 21.2% in controls, 44.1% in primary carcinomas and 32% in metastatic cancer cells. Differences which were significant were control v. primary tumour, P < 0.000001; control v. metastasis, P < 0.01 and primary tumour v. metastasis, P < 0.006. In 57 (60%) of the primary tumours there was positive staining in over 40% of tumour cells. We were not able to demonstrate any relationship between macroscopic or microscopic features and PCNA expression. However, tumours confined to the mucosa expressed PCNA more frequently than did more advanced tumours.

Biomarkers, Tumor↗
PubMed1993

DNA content in gallbladder carcinoma: a flow cytometric study of 96 cases.

The DNA content in gallbladder carcinoma and its relation to histological and cytological features was studied in 79 primary gallbladder carcinomas and 16 metastases. Abnormal DNA content was observed in 48 (51%) of 95 cases. In primary carcinomas, 44 (55.6%) showed a diploid DNA content, and 35 (44.4%) were aneuploid. The majority of the metastatic lesions were aneuploid DNA (81.3%; P = 0.006). Marked differences in the coefficient of variation estimated by manual, Kosugi and Dean methods were detected (P = 0.005). Seventy-one per cent of early gallbladder carcinomas had a normal DNA content. In contrast 54% of the cases with subserosal or serosal infiltration had normal DNA content. In primary tumours the degree of architectural atypia had a close relationship with the degree of cellular atypia (P = 0.00001). Only two (15%) of 13 cases with mild architectural atypia, and 34 (51.5%) of 66 cases with marked architectural atypia were aneuploid. Only one (10%) of 10 cases with mild cellular atypia and 35 (51%) of 69 with high cellular atypia had abnormal DNA content (P = 0.01) The importance of DNA content as a marker in gallbladder carcinoma remains uncertain and its clinical importance requires further clinicopathological studies.

Adenocarcinoma, Papillary↗
PubMed1993

Fatal bile pulmonary embolism following percutaneous transhepatic cholangiodrainage: case report and literature review.

Bile pulmonary emboli were present at autopsy in a seventy-year-old woman who had undergone percutaneous transhepatic cholangiodrainage for pancreatic carcinoma obstructing the common bile duct. The patient also developed hemobilia following the drainage. In spite of emergency surgery, she died on the third day after the operation. Microscopic findings of the lungs at autopsy disclosed numerous bile emboli in the smaller arteries, arterioles, and capillaries. Review of the literature showed 13 cases of bile pulmonary embolism, 10 of which had an obvious history of marked jaundice and trauma to the liver, like the present case. Bile enters the systemic circulation through a fistulous communication made by trauma between the biliary tree and the hepatic vein.

Aged↗
PubMed1993

[Relationship of an extracellular matrix protein, tenascin and breast diseases].

Tenascin is an extracellular matrix glycoprotein consisting of six disulfide-linked subunits with molecular masses of 190-250 kDa. Molecular analysis of the tenascin gene revealed that it contains a region homologous to epidermal growth factor genes, repetitive sequences of the type III fibronectin and the fibrinogen gene. Culture studies have shown that tenascin has multiple functions including cell attachment and detachment, promotion and inhibition of neural crest cell migration, cell growth stimulation and hemagglutination. Immunohistochemically, tenascin shows a characteristic and spatially restricted distribution. In mouse mammary glands, tenascin protein is demonstrated in the dense mesenchyme present around growing epithelia during embryogenesis and oncogenesis. Tenascin is expressed in normal human adult breast tissue and benign conditions, although it is expressed more abundantly in breast cancer tissue. Prominent tenascin staining is found in dense cancer-mesenchymal junctions. The staining positivity is significantly correlated with metastasis to regional lymph nodes and tumor grade. Tenascin positive patients have a significantly poorer prognosis compared with tenascin-negative patients. Although the biological functions of tenascin in breast cancer tissue have not yet been clearly elucidated, tenascin staining in surgical tissue specimens might be useful when applied to detect a subgroup of breast cancer patients who have a poorer prognosis.

Animals↗
PubMed1993

[Stomach and gallbladder cancer. Analysis of cell cycle phases by means of flow cytometry].

The characteristics of the different phases of cell cycle were analyzed in paraffin embedded samples of gall bladder cancer (n = 96) and gastric cancer (n = 40). Computational programs that included Dean, Kosugi and manual methods were used. No differences in variation coefficients were observed between tumors with normal or aneuploid ADN content, with any of the employed methods. Histograms with variation coefficients over 10% were not considered. No differences were observed between the two forms of analysis of Kosugi's method; however there were differences between the manual method and Kosugi's and Dean's methods. The percentage of cells in G0/G1 phase varied between 74.1 and 81.5% according to the employed method. The obtained percentages with Kosugi's method with normal distribution were significantly lower in all the studied groups. These percentages fluctuated between 79.7 and 94.4% in tumors with normal ADN content and between 60.3 and 80.4% in tumors with abnormal ADN content. The proportion of cells in phase G2/M was lower and in phase S lower and more homogeneous among diploid compared to aneuploid tumors. These differences were observed only in primary tumors and not in metastases.

Aneuploidy↗
PubMed1993

[A biological and morphological study of ovoid and spindle cells in malignant fibrous histiocytomas].

To clarify the histogenesis of malignant fibrous histiocytoma (MFH), ovoid and spindle cells, the major components of this tumor, were biologically and morphologically studied using the following methods: (1) flow cytometric nuclear DNA analysis, (2) argyrophil staining for nucleolar organizer regions (Ag-NORs), (3) separation of MFH cells into the two types described above using a flow cytometric cell sorting system, (4) electron microscopic morphological observation, and (5) immunohistochemical examination. Specimens were obtained from 24 cases of soft-tissue MFH and 7 cases of MFH in the bone, which were treated in our institute. In ovoid cells, aneuploid pattern was shown by nuclear DNA analysis and high proliferation activity was found on Ag-NORs staining. Ultrastructural analysis showed that the ovoid cells had malignant characteristics and were presumedly histiocytic in origin. Immunohistochemical examination also, supported histiocytic origin. However, spindle cells were not identified as malignant tumor cells by the various methods described above. Although the histogenesis of MFH remains to be elucidated, these findings provide interesting information.

Adult↗
PubMed1992

Presence of ras oncogene mutations and human papillomavirus DNA in human prostate carcinomas.

The frequency of H-ras, K-ras, and N-ras mutations and the presence of high-risk human papillomavirus (HPV 16, 18, and 33) DNA were studied in 75 paraffin-embedded specimens obtained from 68 Japanese patients with a variety of prostate carcinomas by using polymerase chain reaction and DNA hybridization with sequence-specific oligonucleotides. Ten specimens each of normal and benign hyperplastic prostatic tissues from the same number of patients were also examined for this analysis. Of 68 carcinoma cases, ras gene mutations were present in 16 cases (24%) and HPV DNAs in 28 cases (41%). Eleven mutations were detected in codon 61 of H-ras, 4 in codon 12 of N-ras, and 2 in codon 61 of K-ras. HPV 16, 18, and 33 DNAs were found in 11, 17, and 5 cases, respectively. Eight of the 16 cases with ras mutation also harbored HPV DNAs. The frequency of ras mutations and the HPV infection increased in patients with advanced stages of the tumor and with the higher Gleason score. There was the predominant presence of H-ras codon 61.2 (CAG-->CTG) mutation and HPV 18 DNA in prostatic carcinomas metastasizing to the bone. None of the normal or benign hyperplastic prostatic specimens contained either ras mutation or HPV DNA. Our results suggest that ras gene mutations and HPV infections are relatively frequent, at least in prostate carcinoma of Japanese patients. These two factors appear to be related to the progression of the tumor. Moreover, H-ras codon 61.2 mutation and HPV 18 infection may have some predictive roles for bone metastasis in prostate carcinoma.

Aged↗
PubMed1992

Argyrophilic nucleolar organizer regions in benign hyperplastic and cancerous human prostates.

Argyrophilic nucleolar organizer regions (AgNORs) were examined histologically in cells of benign hyperplastic and cancerous human prostates. Individual dots of AgNORs inside nucleus that were stained as separate granules or as parts of clusters were counted as one, and the average number of dots per cell was obtained by counting 100 nuclei. The number in epithelial cells was similar to that in stromal cells of hyperplastic prostates. In cancerous prostates, the number was larger than in hyperplastic prostates and increased along with upgrading. The number in incidental cancers was smaller than in clinical cancers as compared with cells of the same Gleason pattern. Number correlated with T factor, but not with N and M factors. Response to treatment and cause-specific survival in stage D2 patients receiving endocrine therapy did not correlate with number, although a relationship between Gleason pattern and survival was shown in these patients. It was concluded that AgNORs might not be an indicator to predict prognosis after endocrine therapy, since a number of AgNORs did not influence response to the therapy.

Humans↗
PubMed1992

Comparative study of prostatic carcinoma bone metastasis among Japanese in Japan and Japanese Americans and whites in Hawaii.

Metastatic prostate carcinomas in autopsy cases from three populations 49 cases of indigenous Japanese, 29 cases of Japanese Americans and 14 from whites in Hawaii) were compared in terms of their clinicopathological, immunohistochemical (tenascin and ras p21) and lectin binding (Helix Pomatia antigen, HPA) properties. Only the clinicopathological features were analyzed in the cases of whites in Hawaii. The results indicate that poorly differentiated carcinoma is less common, whereas distant metastasis is more frequent, in indigenous Japanese. Some of the Japanese-American cases with poorly differentiated carcinomas did not show any distant metastases. HPA and ras p21 expression are more common, but tenascin is less common in indigenous Japanese. HPA expression is more common in cases with metastasis, especially with metastasis to the bone and other organs, than nonmetastatic cases. Prostatic cancer cases in indigenous Japanese were more aggressive biologically than those in Japanese Americans, but no phenotypic differences were seen relevant to the presence or absence of bone metastases.

Aged↗
PubMed1992

[Clinicopathological study of autopsy cases of pancreatic carcinoma in the elderly].

A total of 257 autopsy cases of pancreatic carcinoma, including 160 male and 97 female cases with an average age of 68.2 years, were divided into an aged group (70 years or older, 136 cases) and a control group (younger than 70 years, 121 cases), and their respective clinicopathological features were compared. The male to female ratio was 1.2:1 in the aged group and 2.6:1 in the control group. In both groups, abdominal pain was noted in about one-third of the cases as the primary symptom, followed by appetite loss and icterus. Concerning the primary symptoms, the two groups did not differ from each other. The rate of surgical resection was higher in the control group (24.0%) than the aged group (10.3%). Mean survival times were similar in both groups (5.71 months for the aged group and 6.01 for the control group). Intrapancreatic location of the tumor showed similar tendencies in both groups. However, cancer of the head of the pancreas was 2.3 times more common than body/tail cancer in cases aged 80 or more. Approximately 90% of the cases were diagnosed as ductal carcinoma by histological examination. The degree of differentiation was similar in both groups, but the well differentiated type was somewhat predominant in cases 80 years or older. Metastasis or direct invasion was noted to the liver, peritoneum and lung in this order in both groups. Liver and lymph node metastasis were less frequent in cases 80 years or older. Multiple primary cancers were noted in 8.8% of the aged group and 9.1% of the control.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[Gallbladder cancer: immunohistochemical expression of CA-19-9, epithelial membrane antigen, dupan-2 and carcinoembryonic antigen].

The immunohistochemical expression of CA19-9, epithelial membrane antigen (EMA), and carcinoembryonic antigen (CEA) was studied in 103 tissue samples of gallbladder cancer and 25 samples of non tumoral gallbladder lesions. CA19-9 and EMA were positive in over 90% of cancers and non tumoral lesions. Dupan-2 expression was observed in 100% of non tumoral lesions and 78% of cancers. CEA expression was observed in 12% of non tumoral lesions and 89% of cancers. The magnitude of immunohistochemical staining was moderate or intense for all antibodies, except Dupan-2. No differences were observed in the location of positive staining in superficial or deep parts of the tumor. In these lesions the positive staining was cytoplasmatic with a granular and irregular pattern; on the contrary, in the non tumoral lesions, staining was seen in the apical parts of the cell. Calculated sensitivity, specificity and positive predictive value for CEA was 89%, 88% and 96% respectively. If future studies disclose a good correlation between serological and immunohistochemical detection of this antigen, its determination would be potentially useful in clinical grounds.

Antigens, Neoplasm↗
PubMed1992

[Immunohistochemical demonstration of pepsinogens I and II in the gallbladder].

The immunohistochemical expression of pepsinogen I (PI) and pepsinogen II (PII) was studied in 103 gallbladder carcinomas, 25 non tumoral gallbladder lesions and 23 gallbladder cancer metastases. PI was positive in 6% of carcinomas and only in 2% of non tumoral contiguous mucosa. PII was positive in 46% of carcinomas and 43% of controls. Metastases were negative for both enzymes. Pyloric gland metaplasia of non tumoral mucosa adjacent to the tumor expressed PII in 68.9% and PI in 3.4% of cases. The same lesion in non tumoral gallbladders was positive for PII in 66.6% of cases, and no case expressed PI. There was no relationship between PI expression and the histological degree of differentiation. Only tumors with serosal or subserosal involvement were positive for PI. PII had a higher expression in early or well differentiated tumors. Tumors with pyloric gland metaplasia in the contiguous non tumoral mucosa expressed PII more frequently. Our results, based on the expression of PI and PII, suggest a relationship between the presence of pyloric gland metaplasia and some types of gallbladder cancer.

Biomarkers, Tumor↗
PubMed1992

[Endoscopic brushing cytology of esophageal lesions].

Endoscopic esophageal biopsy and brushing cytology were performed simultaneously in 121 cases, 25 of which were diagnosed as esophageal cancer by histologic examination of surgically resected material or at autopsy. Correct diagnosis was made in 88% of the cancer cases by endoscopic biopsy, and the same diagnostic rate was obtained by brushing cytology. Combination of the two methods revealed the cancer in 96% of the cases. There were no cases diagnosed as false-positive or false-negative by cytology. Three cancer cases were diagnosed as suspicious by cytology. Definite diagnosis was not made because of paucity of cells on the slide or of cellular atypism. For the improvement of accuracy in cytologic diagnosis it is important to sample adequate amount of cells, and in situ carcinoma cells should be differentiated from benign atypical cells in esophagitis.

Adult↗