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M Miyazawa

Publications and source records attributed to M Miyazawa.

At least 19 recordsLinked to original sources
PubMed1996

Immunophenotypic characterization of Epstein-Barr virus-associated gastric carcinoma: massive infiltration by proliferating CD8+ T-lymphocytes.

A subset of gastric carcinoma carries Epstein-Barr virus (EBV). The immunophenotypic features of EBV-associated (EBV+) gastric carcinoma, which we have analyzed using 25 EBV+ cases, remain unclear. Frozen tissue samples were stained with antibodies to various immune cell markers. To evaluate the proliferative activity of CD8+ cells, we performed CD8/Ki-67 double staining on paraffin-embedded sections. The results were compared with those in EBV-negative (EBV-) gastric carcinomas. All EBV+ and EBV- gastric carcinoma cells expressed major histocompatibility complex class I, whereas major histocompatibility complex class II expression in tumor cells was more prominent in EBV+ cases. Intercellular adhesion molecule-1 and Fas/APO-1 expression was largely restricted to EBV+ cases. The lymphocytes that infiltrated EBV+ tumor nests were predominantly CD8+ T cells, many of which expressed perforin. Immunoelectron microscopy confirmed a close cell to cell contact between these CD8+ cells and carcinoma cells. CD8+ cells were CD11a+ and CD11b- by flow cytometry performed in one case. The labeling index of Ki-67, the proliferation-associated antigen, in CD8+ cells was 4 times higher in EBV+ cases than in EBV- cases. Our data suggest that these CD8+ cells, which bear a cytotoxic phenotype, are actively proliferating in close contact with EBV+ tumor cells and that the specificity of the CD8+ cells may be directed to EBV and/or cellular antigens expressed by the tumor. This is consistent with a generally favorable prognosis of EBV+ gastric carcinoma. Because the observed T-cell infiltration is insufficient to eradicate the tumor cells, certain immunosuppressive factors were speculated to allow the essentially immunogenic carcinoma cells to establish a macroscopic lesion.

Antigens, CD↗
PubMed1995

Immunization with a single T helper cell epitope abrogates Friend virus-induced early erythroid proliferation and prevents late leukemia development.

Synthetic peptide vaccines containing a single Th cell epitope identified in the gp70 envelope glycoprotein of Friend murine leukemia helper virus induced potent protective immunity against Friend virus infection. H-2a/b mice immunized by a single s.c. injection of the CFA emulsion containing a peptide that represented the N-terminal gp70 epitope recovered slowly from initial development of splenomegaly, and most did not develop late leukemia, whereas most of the control mice given an injection of CFA alone showed sustained leukemic splenomegaly after the challenge with Friend virus. The mice of the same genetic background immunized with the C-terminal Th cell epitope by a single injection of a separate synthetic peptide eliminated virus-producing cells from the spleen within 12 days after inoculation of Friend virus complex, and did not develop early splenomegaly or polycythemia. H-2a/a mice were not protected by immunization with either one of the two synthetic peptides. Earlier production and more rapid class switching of virus-neutralizing Abs were observed in H-2a/b mice immunized with the peptide vaccines after the challenge with Friend virus, compared with the responses of the control mice. Detailed kinetic and immunohistopathologic analyses suggested that Th cells might be directly involved in the growth inhibition and elimination of virus-infected erythroid precursor cells.

Amino Acid Sequence↗
PubMed1995

Biotransformation of an acyclic neolignan in rats.

The biotransformation of an acyclic neolignan, (+)-erythro-(4,7-dihydroxy-3-methoxy-1'-allyl-3',5'-dimethoxy)-8-O-4' neolignan, in rats has been investigated. After administration of (+)-erythro-(4,7-dihydroxy-3-methoxy-1'-allyl-3',5'-dimethoxy)-8-O-4'-++ +neolignan to rat by intraperitoneal injection, urine and faeces were collected. A small amount of (+)-erythro-(4,7-dihydroxy-3-methoxy-1'-allyl-3',5'- dimethoxy)-8-O-4'-neolignan and its metabolic product were obtained from an ethyl acetate extract of the urine, and the largest amount of the same metabolic product was obtained from a dichloromethane extract of the faeces. The sole metabolic product was identified as (+)-(4-hydroxy-3-methoxy-1'-allyl-3',5'-dimethoxy)-8-O-4'-neolignan++ + by spectroscopic methods. Furthermore, biotransformation of (+)-erythro-(4,7-dihydro-3-methoxy-1'-allyl-3',5'- dimethoxy)-8-O-4'-neolignan by intestinal bacteria in rat faeces was also investigated in vitro. Consequently, (+)-erythro-(4,7-dihydroxy-3-methoxy-1'-allyl-3',5'-dimethoxy)-8-O-4'-++ +neolignan was reduced to the same metabolic product and no other metabolic products were produced. These results suggested that intestinal bacteria were concerned in the specific dehydroxylation of (+)-erythro-(4,7-dihydroxy-3-methoxy-1'-allyl-3',5'-dimethoxy)-8-O-4'-++ +neolignan in rats.

Animals↗
PubMed1995

Low expression of adhesion molecules in a case of cutaneous T-cell lymphoma.

A case of cutaneous T-cell lymphoma (CTCL) with low expression of the adhesion molecules lymphocyte function-associated antigen-1 (LFA-1), intercellular adhesion molecule-1 (ICAM-1), and very late antigen-4 (VLA-4) is described. The patient was a 90-year-old man with red round homogeneous tumors on his scalp, trunk, and extremities. He had no history of definite erythema or plaque stage. A biopsy sample taken from a tumor revealed massive infiltration of atypical lymphocytes in the reticular dermis and subcutis with a definite clear zone. The atypical lymphocytes were medium-sized with slightly convoluted nuclei. Immunohistochemically, the infiltrates showed the phenotype of so-called memory T cells. On the basis of these features, the case was diagnosed as CTCL. Expression of LFA-1, ICAM-1 and VLA-4 on the infiltrates was 9%, 13% and 11%, respectively, which is much lower than that in classic mycosis fungoides. This finding suggests that loss of these adhesion molecules may contribute to loss of epidermotropism in the advanced stage of CTCL.

Aged↗
PubMed1995

A single retroviral gag precursor signal peptide recognized by FBL-3 tumor-specific cytotoxic T lymphocytes.

Several dominant T-cell receptors of cytotoxic T-lymphocyte (CTL) clones specific for FBL-3 tumor antigen were clonally amplified in mixed lymphocyte tumor cell cultures derived from an individual immune mouse. Every CTL clone analyzed had a common specificity for a single epitope in the precursor to cell membrane-associated nonstructural gag-encoded protein, Pr75gag, which can be minimally identified by nine amino acid residues, SIVLCCLCL. This epitope is located within the hydrophobic signal sequence motif that mediates translocation of the protein into the endoplasmic reticulum. These novel observations suggest that expression of Pr75gag in FBL-3 tumor cells led to the amplification of CTLs which recognize the signal sequence of the nonstructural gag-encoded glycoprotein precursor.

Amino Acid Sequence↗
PubMed1995

Establishment of a new human cell line, LI90, exhibiting characteristics of hepatic Ito (fat-storing) cells.

BACKGROUND: Thus far, human hepatic Ito (fat-storing) cell lines have not been established. Therefore, functional characteristics of Ito cells have not been fully investigated. EXPERIMENTAL DESIGN: We established a new cell line, LI90, that exhibited characteristics compatible with those of Ito cells from a human hepatic mesenchymal tumor. LI90 cells were examined with phase-contrast microscopy, immunohistochemistry, and cytogenetics, and their vitamin A-storing activity was analyzed. To obtain a marker specific for Ito cells for immunohistochemical analyses, we raised mAb against LI90 cells and clarified the molecular nature of the Ag recognized with the new Ab using an expression cloning approach. RESULTS: LI90 cells showed polygonal shape and had well developed alpha-smooth muscle actin filaments in their cytoplasm. In an overconfluent culture condition, LI90 cells aggregated to form a typical hills-and-valleys structure, LI90 cells produced various connective tissue components, such as collagen types I, III, IV, V, and VI, laminin, and fibronectin. In culture media containing vitamin A, LI90 cells formed many fat droplets in their cytoplasm, and fluorescence characteristic of vitamin A was observed in the droplets. By immunizing mice with LI90 cells, three separate mAb specifically reacting with Ito cells in human liver sections were established, and the Ag recognized with all three Ab were identified as extracellular matrix tenascin. CONCLUSIONS: The above-described morphologic and functional characteristics, including vitamin A-storage and biosynthesis of tenascin, are compatible with those of Ito cells. Therefore, LI90 cells will be useful for in vitro studies of functions of human Ito cells.

Antibodies, Monoclonal↗
PubMed1995

[Surgical treatment of metastatic lung cancer to thoracic supine].

This article reports the author's experience with the surgical treatment of metastatic lung cancer to the thoracic spine. A 65-year-old woman (case 1) had undergone a right upper lobectomy with a diagnosis of adenocarcinoma. Three years later, she complained of severe back pain, and visited our hospital. CT scan showed a metastatic spine disease (Th6 and 7) which caused the back pain. A 59-year-old woman (case 27 was admitted to our hospital complaining of an abrupt onset of paraplegia. Two years ago, she underwent left upper lobectomy with a diagnosis of adenocarcinoma. Urgent examination revealed a large metastatic lesion on Th5 and 6 which compressed the spinal cord. After excision of the tumor as extensively as possible, the both patients underwent surgical decompression of the spinal cord, bone grafting and posterior reconstruction of the spine with a metallic instrumentation. Severe back pain was relieved postoperatively. Improvement of neurological deficit was dramatic in case 2. The goal of surgical treatment of metastatic thoracic spine disease is to improve the quality of the remaining life, by relief of pain and preservation or restoration of neurologic function. The dismal consequences of prolonged bed rest, paraplegia, and a painful premature death can be avoided with thoughtful and timely surgical treatment.

Adenocarcinoma↗
PubMed1995

[Complete disruption of the trachea due to blunt neck trauma--a case report].

A complete disruption of the cervical trachea due to blunt trauma is relatively rare. Because of dislocation of the disrupted trachea and/or bleeding into airway, this is a mostly fatal accident. This article reports the author's experience with the successful surgical treatment of the complete disruption of the cervical trachea. A 60-year-old man suffered from a cervical blunt trauma by traffic accident and referred to our hospital. He had a dyspnea and severe subcutaneous emphysema around neck and anterior chest wall. Urgent fiberoptic bronchoscopy (FOB) revealed a complete disruption of the cervical trachea. After intubation under guide of FOB, he underwent an end to end anastomosis of the disrupted trachea from cervical approach. Tracheostomy was performed two months later, because of his bilateral recurrent nerve paralysis. The patient is alive and well 25 months after surgery. It should be emphasized that early diagnosis and adequate management are important to save patients with complete disruption of the trachea due to blunt trauma.

Accidents, Traffic↗
PubMed1995

Management of chylothorax after pulmonary resection.

BACKGROUND: Conservative management with intrapleural drainage and total parenteral nutrition (TPN) has been the first choice of treatment for postoperative chylothorax. With this approach, however, it usually takes several weeks for the chylothorax to resolve and it is sometimes unsuccessful. In this study, we reviewed seven patients who had chylothorax develop after pulmonary resection for primary carcinoma of the lung. STUDY DESIGN: The patients were treated according to a "one-week trial" that consisted of one week of observation with intrapleural drainage and maximum parenteral nutritional support followed by operative intervention if the effect of the conservative therapy was not adequate. When the chylous leak was decreased to less than 100 mL/day or less than 15 percent of the maximum daily drainage volume after the "one-week trial," the conservative management was continued for two more weeks. After observation for three weeks, oral intake was begun and a final evaluation of the treatment was made. RESULTS: One patient did not consent to the "one-week trial" and underwent operative treatment on the third postoperative day. Two patients had chylous leaks less than 100 mL/day or less than 15 percent of the maximum daily chylous leak after one week observation. Conservative management with TPN was continued in these patients for two more weeks and operation was performed in one on the 20th day and in the other on the 22nd postoperative day. The remaining four patients underwent operative treatment on the seventh or eighth postoperative day. All of the operations for chylothorax were successful, and chest tubes were removed promptly. These results show that operative management of chylothorax was reliable and safe. The "one-week trial," however, offered few advantages in determining the therapeutic strategy for postoperative chylothorax.

Adult↗
PubMed1994

Lectin histochemistry on the skin of hairless descendants of Mexican hairless dogs.

The skin of hairless descendants of Mexican hairless dogs was investigated lectin-histochemically. Haired dogs were also used for comparative study. In the epidermis of infant pups, lectin staining revealed marked differences between hairless and haired dogs. Griffonia simplicifolia-I (GS-I) bound moderately to the cytoplasm of the stratum basale of hairless dogs, while no binding to that of haired dogs was observed. Bauhinia purpurea (BPA) showed positive staining for the stratum spinosum and basale of hairless dogs, while it was negative or weakly positive for the cytoplasm of both epidermal layers of haired dogs. Maclura pomifera (MPA) showed moderate to intense staining for the intercellular area of the stratum basale of hairless dogs, while no or weak staining was detected in that of haired dogs. Urex europeus-I (UEA-I) bound weakly to moderately to the cytoplasm and the intercellular area of the stratum spinosum of hairless dogs, whereas no or very weak staining was observed in those of haired dogs. Most of the lectins exhibited significant alterations in the epidermal staining pattern between infants and adults. Significant differences were not observed in adult canine epidermis between hairless and haired dogs. In conclusion, lectin histochemistry in hairless dogs revealed that there were different development steps in the epidermal cells between infants and adults.

Animals↗
PubMed1994

Production and characterization of new monoclonal antibodies that distinguish subsets of mink lymphoid cells.

Several hybridoma clones that produce monoclonal antibodies (MAbs) reacting with subpopulations of mink lymphoid cells were established. Two of the MAbs, MTS-4.3 and MTS-9.3, reacted with relatively small populations of surface immunoglobulin (Ig)-negative (Ig-) lymphocytes. MTS-4.3+ and MTS-9.3+ cells were distributed in the thymic cortex and medulla, paracortical areas of lymph nodes, and periarterial lymphoid sheaths of the spleen, indicating that these MAbs identify T lymphocytes. Another MAb, MTB-5.6, reacted with a large proportion of surface Ig+ lymph node cells, but not with surface Ig- cells. In immunohistochemistry this MAb stained dendritic epithelial cells of thymic cortex, large polygonal cells of thymic medulla, a large proportion of lymphocytes in the mantle zone of lymphoid follicles, dendritic-shaped cells of paracortical area, and some lymphocytes and macrophage-like cells of medullary cords and sinuses of lymph nodes. The expression of the cell-surface antigen reacting with MTB-5.6 on Ig+ lymph node cells was increased after concanavalin A stimulation. These new reagents may be useful to analyze cellular basis of the abnormal immune responses observed in Aleutian mink disease, a classical model of human autoimmune diseases.

Animals↗
PubMed1994

Contrasting effects from a single major histocompatibility complex class II molecule (H-2E) in recovery from Friend virus leukemia.

Resistance to erythroleukemia induced by infection with the Friend virus complex (FV) has been mapped to several genes residing both within and outside the murine major histocompatibility complex (MHC). MHC genes located in the A, D, and Qa/Tla regions of the murine H-2 complex have been shown to affect disease resistance through their capacity to regulate various aspects of the host immune response to viral antigens. This study establishes H-2E as the fourth MHC locus controlling immunological resistance to FV. Our investigation into the role of H-2E molecules revealed two distinct and opposite effects on recovery from Friend disease. H-2b/b mice normally lack a functional E gene product and are resistant to high doses of FV. The expression of H-2E molecules in H-2 recombinant or transgenic mice of this genotype resulted in a significant decrease in spontaneous recovery from FV-induced leukemia. In contrast, H-2E expression also appeared to influence recovery from Friend disease in a positive manner, since blocking these molecules with anti-E antibodies in vivo significantly decreased recovery from Friend disease. The data indicate that the positive effects of H-2E molecules derive from their function as restriction elements for helper T-cell recognition of the viral envelope glycoprotein, and we postulate that the negative effects are due to H-2E-dependent deletion in the T-cell repertoire during development.

Animals↗
PubMed1994

Physiology and pathology of host immune responses to exogenous and endogenous murine retroviruses--from gene fragments to epitopes.

Spontaneous and induced immunity against exogenous Friend murine leukemia retrovirus infection is controlled by four H-2-linked host genes and a single non-H-2 gene. Recognition of the envelope glycoprotein gp70 of Friend virus by helper T cells is restricted by Ab and hybrid Eb/k(d) class II MHC molecules. By expressing portions of the env gene and by utilizing synthetic oligopeptides, an Ab-restricted and a hybrid Eb/d-restricted helper T cell epitopes were identified in the N-and C-terminal portions of gp70, respectively. These epitopes differ in their amino acid sequences from the previously reported endogenous retroviral peptides naturally presented by mouse MHC class II molecules. Possible roles of recombinant polytropic viruses in the induction of autoimmune responses against endogenous retroviral antigens are also discussed.

Amino Acid Sequence↗
PubMed1994

[Noninvasive regional cerebral blood flow measurements by 99mTc-HMPAO using only three-head SPECT system].

A special bed and a new software program were developed for noninvasive regional cerebral blood flow (rCBF) measurements by 99mTc hexamethylpropylene amine oxime (99mTc-HMPAO) using only three-head SPECT system, Siemens MULTI-SPECT3. A large field gamma camera with a minimum of 38 cm-diameter is required for simultaneous acquisition of time activity curves of brain and aortic arch in this noninvasive method. A special bed with short width was designed and inserted obliquely into the gantry of the SPECT system to acquire both time activity curves of brain and aortic arch with the use of diagonal length (51 cm) of a gamma camera with 31 x 41 cm width. Moreover a software program was developed for processing a series of the graphical analysis of time activity curves, Lassen's linearization correction of SPECT images, and drawing of a rCBF map. This noninvasive rCBF measurement using only MULTISPECT3 in a short period with high spatial resolution is quite useful for routine clinical studies.

Brain↗