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T Iwanaga

Publications and source records attributed to T Iwanaga.

At least 127 records · Page 7Linked to original sources
PubMed1997

Expression of carbohydrate antigen sialyl Le(a): a new functional prognostic factor in gastric cancer.

PURPOSE: The prognostic value of the altered expression of carbohydrate antigens sialyl Le(a) (sLe(a)) and sialyl Le(x) (sLe(x)), which have been implicated as functional ligands in heterotypic-cell-adhesion systems in the multistep process of tumor metastasis, were evaluated. PATIENTS AND METHODS: The level of expression of sLe(a) and sLe(x) antigens was examined immunohistochemically in paraffin-embedded tumor samples from 137 patients who underwent resection for gastric cancer. Correlation between the antigens' expression, various established clinicopathologic factors, and prognosis were studied by univariate and multivariate analysis. RESULTS: Tumors that were positive for the sLe(a) antigen were significantly more likely to be large (P = .035), to be localized at the proximal third of the stomach (P = .018), to have an infiltrate appearance (P = .013), to have an invasive mode both in depth of invasion (P = .028) and in lymphatic invasion (P = .002), and to be classified as late stage (P = .011) than those that were negative for sLe(a), whereas the sLe(x) antigen status was not correlated with any clinicopathologic factors. The overall survival of patients with an sLe(a)-antigen-positive tumor was significantly poorer than that of those with an sLe(a)-antigen-negative tumor (P = .0001). Survival within each pathologic stage differed also (stage I, P = .030; stage II, P = .046; stage III, P = .026, respectively). A Cox regression analysis with multiple covariates showed that positive sLe(a) antigen status was an independent prognostic factor for a worse outcome in patients with gastric cancer. According to the mode of recurrence, increased sLe(a) antigen expression significantly affected both peritoneal dissemination and liver metastasis. CONCLUSION: Increased expression of the sLe(a) antigen may serve as a potent prognostic indicator for recurrence in patients with gastric cancer. Careful follow-up and intensive therapy are required for patients with an sLe(a)-antigen-positive gastric cancer.

Adenocarcinoma↗
PubMed1997

Hydra regeneration from recombined ectodermal and endodermal tissue. II. Differential stability in the ectodermal and endodermal epithelial organization.

Hydra tissue consists of the ectodermal and the endodermal layers. When the two layers were separated by procaine treatment and then recombined, the ectodermal epithelial cells spread as a single cell layer over the endoderm as in epiboly in vertebrate embryogenesis, and the resultant spherical structure subsequently regenerated into a complete hydra. In this study, light and electron microscopy were used to examine the structural changes which took place in the cells and tissue during this epibolic ectodermal spreading process. Within a few hours after tissue recombination, the endoderm underwent dramatic changes; it lost its epithelial sheet organization, and turned into a mass of irregularly shaped cells without the apical-basal cell polarity initially present. In contrast, the ectoderm maintained its basic epithelial sheet organization as it spread over the endoderm. Later, the endodermal epithelial cells reorganized themselves into a single-layered epithelial sheet underneath the spreading ectodermal layer. The resultant spherical structure consisted of a single layer of ectodermal epithelial cells outside, a single layer of endodermal epithelial cells inside, and an empty cavity in the center as in normal hydra tissue. This structure regenerated into hydra in the following days. These and other observations demonstrate that the two-layered epithelial sheet organization is highly dynamic, and that its stability is maintained by strong interactions between the two layers in normal hydra. It is suggested that this dynamic nature of the hydra tissue, particularly the high plasticity of the endodermal epithelial sheet organization, may be an important element for the high regenerative capacity of this organism.

Animals↗
PubMed1997

Production of a monoclonal antibody (59.4) against canine lymphocyte surface antigen and its immunohistochemical application.

A monoclonal antibody was produced by immunizing BALB/c mice with freshly prepared canine thymocytes and peripheral blood leukocytes. The antibody, designated 59.4, was of the IgG1 subclass type and mainly reacted with lymphocytes. In single-color flow cytometric analysis, lymphocytes from the peripheral blood, thymus and spleen were graded into three categories according to their fluorescence intensity labeling by antibody 59.4: weakly, moderately and intensely positive cells. Two-color analysis revealed that a major population of CD8-positive cells were intensely labeled by antibody 59.4, but less than 50% of CD4-positive cells were moderately reacted with antibody 59.4. Immunohistochemically, thymocytes in the medulla showed moderately intense immunoreactivity to 59.4, but most lymphocytes in the cortex were negative in reaction. Immunostaining using antibody 59.4 demonstrated characteristic aggregations of 59.4-positive lymphocytes in the reticulum cell-free region of the thymic medulla. In the spleen, scattered lymphocytes in the outer layer of the marginal zone and in the red pulp were intensely labeled by antibody 59.4, while lymphocytes gathering in the mantle zone and periarterial lymphatic sheath (PALS) were moderately stained. Antibody 59.4 appears to recognize an antigen which is expressed by a more-differentiated T cell-lineage but not by immature T cells in the thymic cortex.

Animals↗
PubMed1997

Apoptosis of enterocytes induced by inoculation of a strain of attaching and effacing Escherichia coli and verotoxin.

When verotoxin (VT)-producing attaching and effacing Escherichia coli (AEEC, serotype O5: H-) were inoculated perorally into 10-day-old rabbits, attaching of the E. coli to enterocytes and effecting of their microvillous portion were observed extensively from the ileum to the colon. Subsequent apoptotic changes of the infected enterocytes were demonstrated by the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL) reaction and electron microscopy. Apoptosis was also induced in cultured Vero cells by inoculation of VT extracted from the AEEC. This study clarified that VT-producing AEEC induce apoptosis of enterocytes, causing mucosal damage.

Animals↗
PubMed1997

Intraepithelial gamma delta T cells are closely associated with apoptotic enterocytes in the bovine intestine.

The T cell population in the intestinal epithelium, comparable in size to the T cell pool in the spleen, is characterized by the predominant distribution of T cells bearing gamma delta T cell receptors. To determine the functional significance of the intraepithelial lymphocytes, we observed gamma delta T cells present in the jejunal epithelium in cattle, in which there is predominance of gamma delta T cells. Immunohistochemistry of frozen sections demonstrated that gamma delta T lymphocytes were densely distributed in the villous epithelium but there were fewer in the lamina propria and they were not present in the crypt epithelium. Ultrastructurally, intraepithelial gamma delta T cells were characterized by possessing electron-dense granules and interdigitating with enterocyte cytoplasm. Enterocytes, which were inserted by processes of intraepithelial lymphocytes or contacted by their cell bodies, showed morphologic changes seen in apoptotic cell death, such as elevated electron density of the cytoplasm and condensation of the chromatin. Apoptotic cells and cell debris were found in macrophages, which gathered in the subepithelial region of villus tips. These findings suggest that in the small intestine of cattle, gamma delta T cells are involved in the renewal of epithelial cells by inducing apoptosis of epithelial cells.

Animals↗
PubMed1997

[The combination of amoxicillin-clavulanic acid and ofloxacin in the treatment of multidrug-resistant Mycobacterium tuberculosis].

A 67-year-old [correction of 53] man with multidrug resistant tuberculosis (MDR-TB) had been persistently positive for acid-fast bacilli (AFB) both on sputum smear and also on culture with the Ogawa egg medium for 30 years since 1951. The case had been treated previously with isoniazid, rifampin, streptomycin, ethambutol, kanamycin, ethionamide, paraaminosalicylate and cycloserine; however, M. tuberculosis strains isolated from this patient acquired a high resistance to all of these agents. Then, a new regimen of chemotherapy, INH combined with ofloxacin (OFLX) and amoxicillin-clavulanic acid (AMPC/ CVA), was applied to the case. He was successfully treated with this regimen, and a marked decrease in the amount of AFB on smear as well as on culture was observed during the course of chemotherapy. No adverse effects were seen meanwhile. These data suggest that it is worth while to try a regimen containing AMPC/CVA and OFLX in the treatment of MDR-TB.

Aged↗
PubMed1997

A monoclonal antibody, 169.1, against canine leukocyte surface antigen identifies cytoskeletal components in epithelial cells and peripheral neurons.

Monoclonal antibodies were produced by immunizing BALB/c mice with freshly prepared canine thymocytes and peripheral blood leukocytes. Flow cytometric analysis of canine peripheral blood leukocytes showed that an antibody, designated 169.1, recognized about 60% of non-lymphoid cells, but reacted with less than 3% of lymphocytes. Immunohistochemistry using frozen sections showed that several types of epithelial cells such as epithelial reticulum cells in the thymus and ductal system in the parotid gland exhibited an intense positive reaction to antibody 169.1. Moreover, the ellipsoidal sheath in the spleen and non-myelinated nerve fibers in the peripheral nervous system had selectively positive reactions; in the latter, filamentous structures were visible under a light microscope. In contrast to the data from the flow cytometric analysis, no leukocytes on sections reacted with 169.1. Immunoblot assay revealed that 169.1 recognized antigens with molecular weights of 48 and 52 kDa under reducing conditions. These findings characterize 169.1 as an antibody against a cytoskeletal protein rich in epithelial cells and neurons.

Animals↗
PubMed1997

[PyNPase activity in primary and metastatic colorectal cancer].

5'-Deoxy-5-fluorouridine (5'-DFUR) is converted to 5-FU by the enzyme of Pyrimidine nucleoside phosphorylase (PyNPase). Its efficacy for lung metastases from colorectal cancer is known. So we investigated PyNPase activity in primary and metastatic lesions of colorectal cancer patients. The results revealed that PyNPase activity (microgram 5-FU/mg protein/hour) (mean +/- SD) was 122.1 +/- 61.1 (n = 48) in primary lesions, 91.6 +/- 48.3 (n = 4) in lymph node metastases, 135.2 +/- 56.4 (n = 10) in liver metastases and 168.2 +/- 79.8 (n = 11) in lung metastases. In non-cancerous tissues adjacent to the cancer lesions, PyNPase activity was 51.5 +/- 18.8 in normal colorectal mucosa, 61.8 +/- 24.7 in normal liver and 43.0 +/- 21.2 in normal lung. These results demonstrated that PyNPase activity in the cancer lesions reached significantly higher levels than in the non-cancerous tissues (p < 0.01); and the T/N ratio of PyNPase activity in lung was also significantly higher than in primary or other metastatic lesions (p < 0.05). It was surmised that the clinical response of colorectal cancer to 5'-DFUR had been influenced by PyNPase activity.

Adenocarcinoma↗
PubMed1996

Assessment of serum CYFRA 21-1 in lung cancer.

BACKGROUND: Cytokeratins are the intermediate filaments of the cytoskeletal protein located in normal epithelia, tumor, and cultured cells. Recently, a fragment of cytokeratin subunit 19, referred to as CYFRA 21-1, detected in the serum of patients with nonsmall cell lung cancer, has been reported as a new tumor marker. This article reports the results of a study of serum fragment CYFRA 21-1, measured by immunoradiometric assay, as a marker of lung cancer. METHODS: One hundred fourteen patients with primary lung cancer, 6 patients with malignant solid tumor, 116 patients with a variety of benign diseases, and 29 normal individuals were entered into the study. Serum CYFRA 21-1 levels were obtained by means of immunoradiometric assay using the CYFRA 21-1 EIA (enzyme immunoassay) kit. In addition, we studied other tumor markers, including carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC), and neuron specific enolase (NSE), as a means of lung cancer diagnosis. RESULTS: The diagnostic accuracy and sensitivity of serum CYFRA 21-1 for the detection of lung cancer were highest among the four markers. The serum CYFRA 21-1 levels were most highly elevated in lung carcinoma patients (in particular UICC Stage IV patients) across different histologic types and attained 85.1% sensitivity when using a threshold of 3.5 ng/mL. The diagnostic sensitivity for detecting lung carcinoma was substantially enhanced by means of combined assays of CYFRA 21-1 with CEA overall for lung cancer, with SCC for squamous cell carcinoma, and with CEA for adenocarcinoma. CONCLUSIONS: These findings suggest that serum assays of CYFRA 21-1 are clinically useful for the diagnosis of lung carcinoma.

Adolescent↗
PubMed1996

Selective uptake of intraluminal dextran sulfate sodium and senna by macrophages in the cecal mucosa of the guinea pig.

The involvement of macrophages in the passage of intraluminal substances into the lamina propria was examined in the large intestine of the guinea pig. Dextran sulfate sodium (DSS) and senna, which, experimentally, induce ulcerative colitis and melanosis coli, respectively, were chosen for examination, since these substances are visible under the microscope without any special treatment. DSS (MW 50,000) and senna were orally administered to guinea pigs. In tissue sections of the intestine, the presence of DSS was demonstrated by toluidine blue staining, while senna was visible under the light microscope as brown pigment. In the large intestine of guinea pigs, macrophages were most numerous in the cecum, decreasing in number towards the rectum. Metachromatic reaction due to DSS was first recognized in the epithelium of the cecum, and was subsequently incorporated by macrophages. The presence of DSS, either in the epithelium or in macrophages, was not recognized in the small intestine or the distal colon. Senna pigmentation was also limited to the cecum and proximal colon, in which pigmented macrophages aggregated in the lamina propria. The two different substances administered orally were taken up in the cecum, and partly also in the proximal colon; the substances passed through the epithelium and were incorporated by macrophages. This finding suggests the existence of a weak point in the intestinal barrier in this particular portion of the intestine.

Animals↗
PubMed1996

Development of T-lymphocyte subpopulations in the postnatal chicken oviduct.

Postnatal development of t-cell subpopulations in the oviduct was investigated in the Dekalb strain of the White Leghorn chicken by using an immunohistochemical method. T-lymphocytes first infiltrated the oviduct at 5 weeks. The number of T cells peaked at 15 weeks in the magnum, isthmus and uterus, and at 19 weeks in the infundibulum and vagina. The epithelium of the oviduct contained both granular and agranular lymphocytes. TcR1+ cells were predominant in the epithelium, whereas TcR2+ cells were more numerous than TcR1+ cells in the lamina propria. TcR3+ cells were absent from the epithelium and were not numerous in the lamina propria. CT8+ cells, equivalent to CD8+ cells in mammals, were located both in the epithelium and in the lamina propria. The relative frequency of T-cell subpopulations was found to be higher in the vaginal part than in the other parts of the oviduct. These results suggest that the postnatal developmental changes of T-cell subpopulations depend on different anatomical regions of the oviduct and on the age of the chicken.

Animals↗
PubMed1996

Lymphocyte subpopulations in the mammary gland of the goat.

Mammary glands of pregnant, lactating and resting goats were studied by immunohistochemistry for lymphocyte subpopulations using a panel of monoclonal antibodies. All T lymphocyte subpopulations that may have a role in the immune response, CD2+, CD4+, CD8+ and gamma delta T cells and subsets, were present in the mammary gland and were noted to increase in number progressively during pregnancy, decrease significantly during lactation, and then moderately increase during the resting period. CD4+ cells, the predominant cell type in the mammary gland, were located mainly in the connective tissue, whereas CD2+, CD8+ and TcR1-N24+ cells were predominant in the intraepithelial areas. TcR1-N6+ cells were detected almost exclusively during pregnancy, being localized mainly in the connective tissue. Their proportion decreased markedly following parturition. Very few WC1-N3+ and -N4+ cells were detected in the mammary gland. It is suggested that the majority of gamma delta T lymphocytes in the mammary gland of the goat are CD2+ CD8+ WCl-, a distinctive subset from that of the WCl+ subset in peripheral blood.

Animals↗
PubMed1996

Clinical features of small hepatocellular carcinomas as assessed by histologic grades.

BACKGROUND: Ninety-seven patients with small hepatocellular carcinomas (HCCs) measuring 3 cm or less in size and three patients with adenomatous hyperplasia who underwent radical hepatic resection were examined in this study. METHODS: The lesions were classified into four groups according to the following histologic grading criteria: group A, adenomatous hyperplasia (n = 3); group B, early HCC (n = 6); group C, well-differentiated HCC (wHCC) (n = 32); and group D, moderately or poorly differentiated HCC (n = 59). The involvement factors that seemed to be important or to characterize the progression of HCC and the survival rates were compared among the four histologic groups. RESULTS: The frequency of patients with tumors larger than 2.0 cm in size and that of patients with 200 or more ng/ml serum alpha-fetoprotein increased with the progression of histologic malignancy. Tumor staining on the angiogram, capsular formation, and extranodular invasion were never seen in groups A and B, but they began to appear in group C and increased remarkably in group D. The 5-year survival rates of the patients in groups B, C, and D were 100%, 60%, and 27%, respectively, and statistically significant differences were seen among them. In comparative evaluation of the group C patients the lesions that showed no tumor staining had no capsule, and those that had no capsule had no extranodular invasion. The 5-year survival rate of patients with wHCC without extranodular invasion (81%) was significantly higher than that of patients with extranodular invasion (35%) (p < 0.05). CONCLUSIONS: It may be recommended to provide the category of wHCC without extranodular invasion for pathologic classification of clinically early HCC (i.e., HCC of high curability).

Aged↗
PubMed1996

Detection of gastric cancer micrometastases in lymph nodes by amplification of keratin 19 mRNA with reverse transcriptase-polymerase chain reaction.

A sensitive method for the detection of gastric cancer micrometastases in lymph nodes was developed. The method was based on amplification of keratin 19 mRNA by reverse transcriptase-polymerase chain reaction (RT-PCR). Keratin 19 RT-PCR showed that keratin 19 mRNA was expressed in all 12 gastric cancers, but not in any of 20 normal control lymph nodes, indicating that keratin 19 mRNA is a good target of RT-PCR for the detection of gastric cancer micrometastases in lymph nodes. Serial dilution studies of RNA extracted from gastric cancers against RNA extracted from control lymph nodes demonstrated that the detection sensitivity of the keratin 19 RT-PCR method was one cancer cell in 10(3)-10(5) lymph node cells. Detectability of lymph node metastases was compared between keratin 19 RT-PCR and conventional histological examination, using 100 lymph nodes obtained from 12 gastric cancer patients. Keratin 19 mRNA was detected in all of the seven lymph nodes which were histologically metastasis-positive. Of the 93 lymph nodes which were histologically metastasis-negative, 79 were found not to express keratin 19 mRNA but 14 were found to express keratin 19 mRNA, indicating that these lymph nodes contained micrometastases which could not be detected by histological examination. These results demonstrate that keratin 19 RT-PCR is a more sensitive method than histological examination for the detection of gastric micrometastases in lymph nodes.

Adult↗
PubMed1996

Hormonal regulation of T-cell subsets in the oviduct: an immunohistochemical study using sex-hormone-treated chicken.

The present immunohistochemical study deals with dynamic alteration of T-cell subsets in the oviduct sex-hormone-treated chickens. Monoclonal antibodies (CT3, CT4, and CT8) specific for the chicken homologues of CD3, CD4, and CD8 were used in estrogen- or progesterone-treated chickens. In control animals, no lymphocytes appeared throughout the oviduct until 4 weeks of age. When 7-day-old chickens were injected with either diethylstilbestrol (DES) or (DES) plus progesterone, T cells immunoreactive for CT3 first infiltrated the oviduct at 12 hr after the hormone treatment. Their frequency of occurrence rose from 48 to 96 hr. Subsequently, CT3+ cells in the magnum declined in number per area coincident with the proliferation of albuminous glands in the lamina propria, while in the vagina no decline of T cells was observed. The population of T-cell subsets in the lamina propria of both the magnum and vagina was significantly higher in the DES-treated chickens than in DES plus progesterone-treated chickens. Among T-cell subsets CT8+ cells were more numerous than CT4+ cells throughout the study, this relative frequency being shared by normal adults. Depopulation of lymphocytes from the thymus, spleen and cecal tonsil, their mobilization to the circulating blood, and subsequent dynamic infiltration into the oviduct suggested that the sex hormones induced the traffic of T cells from the lymphoid organs into the oviduct.

Animals↗
PubMed1996

Cellular distribution of the P2X4 ATP receptor mRNA in the brain and non-neuronal organs of rats.

RNA blot analysis has shown that an ionotropic ATP receptor P2X4 is widely distributed, as compared with other P2X subtypes. Cellular distribution of the P2X4 ATP receptor mRNA was investigated by in situ hybridization technique in the brain and non-neuronal organs. In the brain, transcripts of the P2X4 were widely distributed in various regions, with the highest signals in the cerebellar Purkinje cells and granule cells. In other organs, intense and selective expression was detected in seminiferous tubules of the testis and intestinal crypts of the colon, suggesting an involvement of ATP in spermatogenesis and intestinal secretion. A low but significant level of the P2X4 mRNA was detected in the adenohypophysis and the cortex of the adrenal gland. The tissue- or cell-specific expression of the P2X4 mRNA is of importance to understand the functional roles of the purinergic transmission system.

Adrenal Glands↗
PubMed1996

[Quality control of surgery in multicenter study--interinstitutional and individual differences].

UNLABELLED: In a prospective randomized controlled trial (PRCT) of adjuvant chemotherapy for gastric cancer patients participated by 6 cancer center hospitals, inter-institutional and inter-individual differences about several factors related to the surgery and remote survivals were analyzed. From 1988 to 1992, 1,049 evaluable patients were enrolled and stratified to 6 groups according to the grade of the serosal invasion and curability, and analyzed statistically. RESULTS: 1) There were no inter-institutional differences about postoperative survival rate, but there were slight differences about patient's background factors and entry policy of each institution. 2) There were no inter-institutional differences about several factors related to the surgery such as operative time, bleeding volume during operation, and the length of the administration periods. 3) There were no inter-individual differences about the length of the administration periods, but there were a little differences about operative time and the volume of hemorrhage. When the PRCT of adjuvant chemotherapy of which the end point is survival would be designed, no inter-institutional differences about remote survival and surgical operation in each institution should be confirmed before starting the trial.

Chemotherapy, Adjuvant↗