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S Munakata

Publications and source records attributed to S Munakata.

At least 19 recordsLinked to original sources
PubMed2003

Touch imprint cytology and immunohistochemistry for the assessment of sentinel lymph nodes in patients with breast cancer.

AIMS: Accurate evaluation of sentinel nodes is of clinical importance to avoid further surgery for axillary node dissection. A prospective study was carried out to investigate the feasibility and accuracy of touch imprint cytology (TIC) and touch imprint immunohistochemistry (TIHC). METHODS: Two hundred and five sentinel nodes from consecutive 118 patients with primary breast cancer were studied after successful identification of sentinel nodes. Sentinel nodes were sectioned at 2 mm intervals and imprint specimens prepared from all cut surfaces were subjected to Papanicolaou staining and immunohistochemical staining using anti-cytokeratin antibody. RESULTS: Forty-nine sentinel nodes from 40 patients were positive by permanent section. The sensitivity of TIC was 84% (41/49) per sentinel node and 83% (33/40) on a per patient basis. The sensitivity of TIHC was 86% (42/49) per sentinel node and 83% (33/40) on a per patient basis. When the results of TIC and TIHC were combined, the sensitivity was 88% (43/49) per sentinel node and 85% (34/40) on a per patient basis. Among the 156 negative sentinel nodes, four sentinel nodes from four different patients were consistently positive by TIC and TIHC, but only one patient out of 78 node-negative patients was upstaged. CONCLUSIONS: Touch imprint cytology is sufficiently sensitive for intraoperative evaluation of sentinel nodes. A slight improvement in the sensitivity is expected when immunohistochemistry is used. The combination of these methods provides better sensitivity than either method alone.

Adult↗
PubMed2001

Sialolipoma: a report of seven cases of a new variant of salivary gland lipoma.

AIMS: We propose the designation 'sialolipoma' to establish and characterize a new category of benign lipomatous tumour occurring in salivary glands. Until now, these tumours have not been regarded as a distinct entity in the salivary glands. METHODS AND RESULTS: We evaluated the clinicopathological and immunohistochemical features of seven sialolipomas among 2051 surgically resected primary salivary gland tumours deposited in our files. The seven patients with sialolipoma were five men and two women, aged 20-75 years (mean: 54.4 years). Five tumours had arisen in the parotid gland, one in the soft palate, and one in the hard palate. The tumours ranged from 10 to 60 mm (mean: 38 mm) in maximum diameter. Histologically, the tumours were characterized by a well circumscribed mass composed of glandular tissue and mature adipose elements. The adipose elements in the tumours arising in the parotid gland were more abundant than those arising in the minor salivary gland. The glandular components consisted of ductal, acinar, basal and myoepithelial cells, and closely resembled the cellular and structural compositions of normal salivary gland tissues. These findings were confirmed by immunohistochemical and ultrastructural studies. These components had no atypia, except for the presence of some minor variations, e.g. ductal ectasia with fibrosis and focal oncocytic metaplasia. In all cases, cell proliferative activity, as assessed by Ki67 (MIB1) immunostaining, was low. From these findings, it is likely that our cases were lipomas with secondary entrapment of the salivary gland elements. No recurrence was seen in all cases after superficial parotidectomy, or after surgical excision in the patients with palatal tumours. CONCLUSIONS: We regard sialolipoma as a distinct variant of salivary gland lipoma that can occur in both the major and minor salivary glands. Superficial parotidectomy, or surgical resection in the case of palatal tumours, is an appropriate treatment for this benign tumour.

Adult↗
PubMed2000

Epstein-Barr virus associated B-cell lymphoma of brain developing in myelodysplastic syndrome with c-kit mutation (Try-557 -->stop).

The first case of B-cell lymphoma of brain in a patient with myelodysplastic syndrome (MDS) was reported. A 68-year-old man was admitted because of anemia, fever, and thrombocytopenia and was diagnosed as having MDS (refractory anemia with excess of blasts) on the basis of the findings of bone marrow aspiration and chromosomal analysis. The patient was followed up without chemotherapy, but a brain tumor appeared after 3 years. Histologic and immunohistologic examinations revealed diffuse large B-cell lymphoma. Mutations of the c-kit proto-oncogene (stem cell factor receptor) and the p53 tumor-suppressor gene were examined in the MDS lesion and malignant lymphoma (ML) by the polymerase chain reaction-single-strand conformational polymorphism (PCR-SSCP) method followed by direct sequencing. The p53 mutation was not found in either MDS or ML, but a nonsense mutation (Try-557 --> stop) in exon 11 of the c-kit, which might lead to dysfunction of tyrosine kinase activity, was detected in MDS. This is the first report of c-kit mutation in MDS. Epstein-Barr virus (EBV) genome was demonstrated in the nucleus of brain ML cells by in situ hybridization with EBV-encoded RNA-1 probe. Immunohistochemistry showed that the tumor cells expressed latent infection gene products, including EBV nuclear antigen-2 and latent membrane protein-1. This pattern of latent gene expression was Lat III, which is usually found in malignant lymphomas developing in immunocompromised hosts. These findings suggest that a profound pancytopenia in MDS resulted in an immunodeficient condition, after which EBV-positive B-cell lymphoma of brain developed.

Aged↗
PubMed2000

Induction of chromosomal aberrations and growth-transformation of lymphoblastoid cell lines by inhibition of reactive oxygen species-induced apoptosis with interleukin-6.

Etiological evidence, indicating the relationships between the onset of malignant lymphoma and pre-existing chronic inflammation, has been accumulated. For the autonomous growth of malignant tumor, genetic lesions, such as chromosomal aberrations, amplification of oncogenes, and mutations of genes involved in the cell cycle regulation, must be essential. However, how the inflammation promotes the accumulation of genetic lesions and induces the autonomous growth of lymphoid cells remains unclear. Reactive oxygen species released by polymorphonuclear leukocytes and macrophages are factors causing DNA damage in the foci of inflammation, and thus could play a role in lymphomagenesis. The xanthine/xanthine oxidase (X/XOD) system produces a mixture of hydrogen peroxide and superoxide anion extracellularly, and thus serves as an in vitro source of reactive oxygen species. Cell death of lymphoblastoid cell lines (LCLs) was induced with X/XOD treatment in a dose-dependent manner. DNA fragmentation, which is the characteristic feature of apoptosis, was observed in LCLs at 4-8 hours after X/XOD treatment. Among cytokines such as interleukin-6 (IL-6), IL-10, and interferon-gamma, only pretreatment with IL-6 gave LCLs the resistance to X/XOD-induced cell death in a dose-dependent manner. The proportion of apoptotic cells in X/XOD-treated LCL culture was decreased with IL-6 pretreatment by quantification with flow cytometric analysis. Treatment of LCLs with IL-6 for 48 hours up-regulated bcl-2 mRNA expression. Furthermore, the LCLs repeatedly treated with X/XOD and cultured with or without IL-6 showed many more structural abnormalities of chromosomes than those without X/XOD treatment. Colony forming efficiency of X/XOD-treated LCLs with IL-6 was significantly higher than those without IL-6, and even relatively higher than LCLs without X/XOD treatment. IL-6 could support the survival of non-neoplastic B cells and accelerate the malignant transformation of B lineage cells in inflammatory lesions.

Apoptosis↗
PubMed2000

Primary large-cell neuroendocrine carcinoma of the parotid gland: immunohistochemical and molecular analysis of two cases.

Pulmonary large-cell neuroendocrine carcinoma (LCNEC) is a newly proposed clinicopathologic entity; a few cases of LCNEC have been reported in other sites, such as the uterine cervix and the thymus. In the salivary glands, LCNEC is extremely rare and is not recognized as a specific entity in the World Health Organization classification. We retrospectively reviewed from our files 1675 cases of surgically resected primary parotid gland tumors and found 2 cases of LCNEC that fulfilled the criteria of pulmonary LCNEC. These cases occurred in 72- and 73-year-old men who had short histories of enlarging parotid gland tumors. The tumors were composed of large cells that exhibited organoid, solid, trabecular, and rosette-like growth patterns with a high mitotic rate and a conspicuous tendency for necrosis. The tumor cells were polygonal and characterized by a moderate nuclear:cytoplasmic ratio, coarse chromatin, and conspicuous nucleoli. Immunohistochemical examination revealed that the tumor cells were positive for six general neuroendocrine markers, cytokeratin, p53, bcl-2, epidermal growth factor receptor, and cyclin D1. Markedly reduced expressions of p21Waf1 and p27Kip1 were also noticed. The Ki-67 labeling index was more than 50% in both cases. One case showed loss of heterozygosity at TP53 accompanied by a p53 gene point mutation. Loss of heterozygosity at chromosome 9p21 was detected in both cases; one was accompanied by a p16 gene silent point mutation. Both patients died of the disease, with recurrence 5 months and 4 years after surgery, respectively. These findings indicate that LCNEC is a rare but distinct salivary gland tumor with highly aggressive biologic behavior. Multiple alterations of cell cycle regulators and tumor suppressor genes may play an important role in presenting the biologic characteristics of this rare parotid gland tumor.

Aged↗
PubMed2000

Angiotropic lymphoma: proliferation of B cells in the capillaries of cutaneous angiomas.

We report a 52-year-old patient with cutaneous angiomas on the trunk in association with angiotropic lymphoma involving the nervous system. The lesional skin showed proliferation of atypical B cells in the capillaries. The diagnosis of angiotropic lymphoma with neurological deficits is often difficult before death. Thus, skin biopsy in this case proved to be diagnostic of the central nervous system disease without the risk of brain biopsy. The diagnosis of angiotropic lymphoma in the future may be achievable by biopsy of coincidental angiomas.

Biopsy↗
PubMed2000

Expressions of Fas ligand and other apoptosis-related genes and their prognostic significance in epithelial ovarian neoplasms.

Expression of apoptosis-related proteins, bcl-2, Bax, Fas and Fas ligand (L), in ovarian epithelial neoplasms together with its clinical relevance was examined by immunohistochemistry. They included 36 cases with adenoma, 33 with low potential malignancy (LPM) and 63 with carcinomas. bcl-2 expression was observed in 14 of 36 cases (39%) with adenoma, five of 33 (15%) with LPM (P< 0.05) and 12 of 63 (19%) with carcinoma (P < 0.05). Cases with bcl-2 expression showed more favourable prognosis than those without, but the difference was not statistically significant. There was no difference in frequency of Bax and Fas expression between each histologic category. Fas L expression was observed in one of 36 cases (3%) with adenoma, but in 12 of 33 (36%) with LPM (P < 0.001) and 42 of 63 (67%) with carcinoma (P < 0.0001). In carcinomas, cases expressing Fas L showed a less favourable prognosis than those without (P = 0.02). Density of CD8+ lymphocytes, possibly cytotoxic T-cells, was higher in serous carcinoma with negative Fas L expression than those with positive Fas L expression. These findings suggest that Fas L expressing carcinomas induce apoptosis in infiltrating CTL with Fas expression, and escape from immune surveillance.

Adenoma↗
PubMed2000

Electron microscopic observation of intracellular expression of mRNA and its protein product: technical review on ultrastructural in situ hybridization and its combination with immunohistochemistry.

In situ hybridization (ISH) at the electron microscopic (EM) level is essential for elucidating the intracellular distribution and role of mRNA in protein synthesis. Three different approaches have been applied by the investigators in this EM-ISH study: preembedding method; non-embedding method using ultrathin frozen sections; and postembedding method. In order to obtain satisfactory morphological preservation and retain the messages, we routinely utilized 6 microns-thick frozen sections fixed in 4% paraformaldehyde for the preembedding method and tissues embedded in LR White resin for the postembedding method. The hybridization signal intensity by the postembedding method was lower, and non-specific signals were relatively frequent, in comparison with the preembedding method. The preembedding method thus appears to be easier and better than the postembedding method from the viewpoint of applicability and preservation of mRNA, although quantitative analysis of the expression of mRNA is rather difficult in the preembedding method. EM-ISH is considered to be an important tool for clarifying the intracellular localization of mRNA and the exact site of specific hormone synthesis on the rough endoplasmic reticulum. The simultaneous visualization of mRNA and encoded protein in the same cells using preembedding EM-ISH and subsequent postembedding immunoreaction with protein A colloidal gold complex is also described. This ultrastructural double-staining method for mRNA and encoded protein can be expected to provide an important clue for elucidating the intracellular correlation of mRNA translation and secretion of translated protein.

Animals↗
PubMed2000

[Beneficial effects of CHOP therapy in a case of intravascular large B-cell lymphoma diagnosed by skin biopsy].

We report a case of intravascular large B-cell lymphoma. A 52-year-old man gradually developed dementia and abnormal behaviors, which were later accompanied by spastic paraplegia and sensory disturbance in his lower limbs. MR imaging of his brain showed high signal intensity lesions on T2 imaging. IMP-SPECT images of the brain showed diffuse reduction of radioisotope uptake. Many skin rashes that looked like senile hemangioma were observed on his body. Several of those were biopsied, and the diagnosis of intravascular large B-cell lymphoma was made because of malignant B lymphocytes filling the vessel lumens in one of the seven biopsy specimens. CHOP therapy was performed and found to be effective for the neurological disorders such as dementia, paraplegia, and sensory disturbance. Our case suggests that skin biopsy for more than one sample of the skin rashes is very important for the diagnosis of intravascular large B-cell lymphoma. CHOP therapy might be effective in this case because of early diagnosis by skin biopsy.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

Collagen abnormalities in the spinal cord from patients with amyotrophic lateral sclerosis.

During the last 10 years, we have demonstrated morphological and biochemical abnormalities of skin extracellular matrices in amyotrophic lateral sclerosis (ALS). However, currently little is known concerning collagen of the spinal cord in ALS. We measured the amount of collagen and characterized collagen at light and electron microscopic levels in posterior funiculus, posterior half of lateral funiculus and anterior horn of cervical enlargement of the spinal cord obtained from ten patients with ALS, 11 patients with other neurologic diseases (control group A), and ten patients without neurologic ones (control group B). In posterior half of lateral funiculus and anterior horn, (1) by light microscopy, there was no significant difference in vessel wall area between ALS patients and control groups A and B; (2) ultrastructurally, collagen bundles were more fragmented and widely separated, and the fibrils were randomly oriented in the perivascular space of capillaries in ALS patients, which were not observed in any areas of control groups or in posterior funiculus of ALS patients; and (3) the collagen contents in ALS were significantly lower (P<0.001 and P<0.001, respectively) than those in control groups A and B. Fragmented and widely separated collagen bundles in the interstitial tissue surrounding capillaries and markedly decreased amount of collagen in posterior half of lateral funiculus and in anterior horn of ALS could be related to the degeneration of the upper and lower motor neurons in the spinal cord in ALS, that is, selective neuronal vulnerability in ALS.

Adult↗
PubMed1998

An improved ultrastructural double-staining method for rat growth hormone and its mRNA using LR White resin: a technical note.

An improved new method for the simultaneous visualization of mRNA and encoded protein in LR White resin-embedded specimens is described. This pre-embedding electron microscopical in situ hybridization (procedure) localized rat growth hormone mRNA specifically as high electron-density products on the polysomes of the rough endoplasmic reticulum. A subsequent post-embedding immunoreaction, using protein A colloidal gold particles, identified growth hormone as gold particles both in the cisternae of the rough endoplasmic reticulum and on the secretory granules. In our previous report, we used Epon resin for tissue embedment, which required an etching process using hydrogen peroxide or sodium periodate for immunoreactivity retrieval. In general, osmification and embedment in Epon resin are reported to decrease the immunoreactivity of the targeted protein, and the etching process using hydrogen peroxide or sodium periodate results in deosmification and shades off the signals of mRNA. To resolve these problems, we have recently used LR White resin for tissue embedment. In LR White resin-embedded tissues, retrieval of immunoreactivity using hydrogen peroxide or sodium periodate is not required, and, therefore, the gradation of the signals of mRNA can be avoided.

Acrylic Resins↗
PubMed1998

Muscle pathology in the early stage of Guillain-Barré syndrome.

Although many studies have been performed on nervous tissue pathology in Guillain-Barré syndrome (GBS), much less is known about pathological changes in skeletal muscle in this disorder. We have studied muscle biopsies from 5 patients with GBS, 5 patients with amyotrophic lateral sclerosis (control A), and 5 patients with polyarteritis nodosa (control B). We also examined muscle obtained after death from 7 patients without neurologic or muscular diseases (control C). By light microscopy, all specimens from patients with GBS exhibited necrosis and/or phagocytosis, none of which was observed in the other three controls. Neither small angulated fibers nor small group atrophy was found in patients with GBS and in control C, by contrast with controls A and B. Ultrastructurally, filamentous bodies, subsarcolemmal aggregates of mitochondria, accumulation of glycogen particles, and concentric laminated bodies were present much more frequently in patients with GBS than in all controls. Only GBS patients showed cytoplasmic bodies. These observation suggests that there is muscle involvement in the early stage of GBS and that these muscle changes may have an intimate and important relationship to the pathogenesis of GBS.

Adult↗
PubMed1995

Accommodation power determined with visual evoked cortical potentials in psychogenic visual disturbances.

Accommodation power was measured with pattern visual evoked potentials in 12 normal subjects and three patients suffering from psychogenic visual disturbances and accommodation failure. Steady-state visual evoked cortical potentials recorded by increasing a minus-power lens in front of the eye in 1 diopter steps. The regression line was established from the visual evoked cortical potential amplitudes vs accommodation stimulus plot, and the objective accommodation power was determined by extrapolating the line to zero amplitude. The accommodation power measured by visual evoked cortical potentials was larger by approximately 2 diopters than that obtained subjectively by near-point rule in normal subjects. The subjective accommodation power was remarkably low for their age in each patient but the objective power was normal. These results suggest that the decrease of accommodation in these patients was caused by psychogenic mechanisms, and visual evoked cortical potential measurements of accommodation could provide helpful information for diagnosis.

Accommodation, Ocular↗
PubMed1995

Computer-assisted and visual methods of assessing cellular proliferation in tissue sections from non-Hodgkin's lymphoma a comparison.

OBJECTIVE: To compare computer-assisted and visual methods of assessing cellular proliferation using tissue sections from non-Hodgkin's lymphoma (NHL). STUDY DESIGN: The study group consisted of 20 specimens of NHL (10 indolent and 10 aggressive). Three-micrometer serial sections were prepared and labeled for Ki-67 (MIB1) and argyrophilic nucleolar organizer regions (AgNORs). Labeling was assessed by classic visual inspection and quantitative image analysis. RESULTS: Computer-assisted and visual Ki-67 labeling indices were significantly higher in aggressive than indolent NHL and were linearly related (r = .850, P < .0001). Although the visual and computer-assisted AgNOR counts were significantly higher in aggressive than indolent NHL, the correlation between these two counting methods was not significant (r = .407, P < .075). Linear regression analysis demonstrated a significant correlation between the Ki-67 visual labeling index and visual AgNOR count (r = .630, P < .003); however, no such relationship could be demonstrated between the remaining methods. CONCLUSION: The results of this study suggest that visual and computer-assisted methods of immunohistochemical and AgNOR analysis may not yield comparable results. This fact may be related to the method of analysis and the computer-assisted technique.

Cell Division↗
PubMed1994

Ki-67 expression in vulvar carcinoma.

The proliferative activity of invasive squamous cell carcinoma of the vulva was examined using a Ki-67 equivalent monoclonal antibody (MIB1), which gives a strong immunoreaction in paraffin-embedded tissue. Quantitation of Ki-67 immunostaining was accomplished by image analysis. Ki-67 immunostaining revealed two general patterns of reactivity in vulvar tumors: (a) a diffuse distribution of Ki-67 positive nuclei within the tumor mass and (b) a localized distribution of Ki-67 positive nuclei staining predominantly basilar components of tumor aggregates. The distribution of localized and diffuse patterns did not differ significantly between various clinicopathologic categories (age, histologic type and grade, FIGO stage, and lymph node status). However, the survival times for patients with a diffuse Ki-67 labelling pattern tended to be shorter than those for patients with a localized pattern. Survival curves based on the median positive nuclear area (PNA) calculated by image analysis did not differ significantly. Thus, the pattern of Ki-67 immunostaining, rather than the percentage of PNA, may have prognostic significance in vulvar squamous cell carcinoma.

Aged↗
PubMed1994

Photoreceptor differentiation of retinoblastoma: an electron microscopic study of 29 retinoblastomas.

Retinoblastomas exhibit a unique form of differentiation to produce cell elements similar to those seen in a photoreceptor cell. An ultrastructural study was performed on 29 cases of retinoblastoma to further clarify the cytologic characteristics of the tumor cells. The age of the retinoblastomas averaged 17.1 months and the tumor cells showing photoreceptor differentiation were demonstrated in 10 cases (35%). The findings were especially notable in retinoblastomas with Flexner-Wintersteiner rosette formation (seven cases, 28%). Similar photoreceptor differentiation was also evident in solid cell clusters without rosette formation (four cases, 14%). The presence of photoreceptor elements was assumed to be significantly frequent both in Flexner-Wintersteiner rosettes and in the solid cell clusters. The cell cytoplasm also showed proliferation of long mitochondria and microtubules, reflecting photoreceptor differentiation. The hereditary-type retinoblastoma showed more advanced cell differentiation than the non-hereditary type. Photoreceptor differentiated retinoblastoma showed rather indolent growth compared with the undifferentiated type, and the former can expect a curative treatment by operation. These observations provide additional findings of the biological nature of retinoblastomas.

Cell Differentiation↗