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Shinsuke Suzuki

Publications and source records attributed to Shinsuke Suzuki.

35 records · Page 2Linked to original sources
PubMed2005

[An autopsy case of Down's syndrome with moyamoya syndrome].

We reported an autopsy case of Down's syndrome with moyamoya syndrome. A 30-year-old male with Down's syndrome suffered from a cerebral infarction and died of brain herniation. Cerebral angiography showed vascular abnormalities that were the same as moyamoya disease. Pathological findings revealed multiple stenosis of main trunk of the cerebral arteries. Pathologically, the stenosed vessels showed eccentric intimal thickness with cholesterin deposit, unlike moyamoya disease. There are only two previous reports of autopsied cases of Down's syndrome with moyamoya syndrome. We postulate that a protein encoded on chromosome 21 may be related to the pathogenesis of Down's syndrome with moyamoya syndrome.

Adult↗
PubMed2005

[A case of spontaneous dissection of the cervical carotid artery with pseudoaneurysm].

We experienced the case of a dissecting carotid artery presenting with a pulsatile neck mass. This 60-year-old man was admitted to our department due to a progressive, painful left neck mass. The lesion was diagnosed as a dissecting left internal carotid artery with the subsequent formation of a giant pseudoaneurysm. First, the patient underwent an endovascular treatment using self-expandable stent and Guglielmi detachable coils (GDCs). However, four months after the treatment, recurrence of the pseudoaneurysm happened to him, and he was readmitted to our department. Angiographies revealed an enlargement of the pseudoaneurysm. Then, proximal occlusion of the left internal carotid artery was performed using a balloon and GDCs. Ten months after the second endovascular treatment, since symptoms of the central retinal artery embolism and progression of the mass effect occurred, surgical treatment with trapping and resection of the pseudoaneurysm was performed. We investigated pathologically the surgical specimen and could observe a partial thrombosed wall of the pseudoaneurysm. The multiple neovascular channels in the intima and media layers of the aneurysmal wall could be found, and the vasa vasorum in the adventitia was also noted. We thus suggest that mechanism of the enlargement of the pseudoaneurysm may be due to the retrograde neovascular supplies from the vasa vasorum. As a consequence, repeated bleeding and thrombosis in the dissecting arterial wall may result in the formation of partial thrombosed giant aneurysms.

Aneurysm, False↗
PubMed2004

Direct cell-cell interaction enhances pro-MMP-2 production and activation in co-culture of laryngeal cancer cells and fibroblasts: involvement of EMMPRIN and MT1-MMP.

Matrix metalloproteinases-2 (MMP-2, gelatinase A) has been regarded as a crucial enzyme for tumor progression, invasion, and metastasis by its capability to degrade the basement membrane components, and its activation process is critical for tumor development. Recently, EMMPRIN/CD147, which is a member of immunoglobulin superfamily, has been reported to be highly expressed in tumor cells and induce production of MMPs from fibroblasts adjacent to the tumor cells. In this study, we demonstrated that production of pro- and active forms of MMP-2 by human dermal fibroblasts was enhanced by the direct cell-cell contact with co-cultured HEp-2 cells derived from a human laryngeal epidermoid carcinoma. The results from immunoblotting and reverse transcription-polymerase chain reaction (RT-PCR) analysis indicated that HEp-2 cells express a higher level of EMMPRIN but only a low level of MMP-2 and membrane type 1-matrix metalloproteinase (MT1-MMP), whereas fibroblasts express a higher level of MMP-2 and MT1-MMP and a low level of EMMPRIN. In a mixed co-culture with direct cell-cell contacts, co-cultured HEp-2 cells stimulated the pro- and active MMP-2 production from fibroblasts, but not in a separated co-culture through polycarbonate membrane. Production of pro/active MMP-2 and MT1-MMP (activator of pro-MMP-2) in fibroblasts was induced by the addition of membrane fractions prepared from HEp-2 cells to the fibroblast culture, and the induction was suppressed by the EMMPRIN depletion after immunoprecipitation, signifying the participation of EMMPRIN for the induction and activation of MMP-2. Our results suggest an importance of the direct cell-cell interaction involving EMMPRIN rather than humoral factors such as cytokines for pro-MMP-2 production and activation followed by tumor progression, invasion, and metastasis in laryngeal cancer.

Antigens, CD↗
PubMed2004

Intercellular Adhesive Structures Between Stellate Cells - An Analysis in Cultured Human Hepatic Stellate Cells.

To investigate whether or not hepatic stellate cells can form intercellular junctions with each other, we cultured human stellate cells (LI90) on different kinds of substrata. Intercellular junctions were detected between these cultured stellate cells by transmission electron microscopy (TEM). The molecular components of the intercellular adhesive structures were identified by immunofluorescence microscopy. Immunofluorescence for cadherin and catenins was detected at the adhesion sites between the cultured stellate cells. Thus, the intercellular junctions were indicated to be adherens junctions at the molecular level. The junctions developed in the cultured stellate cells irrespective of the type of substratum. These data suggest that the junctional formation between the stellate cells occurs in vivo as well as in vitro.

Journal Article↗
PubMed2004

Ground-based diffusion experiments on liquid Sn-In systems using the shear cell technique of the satellite mission Foton-M1.

This study reported in this paper was aimed at testing the shear cell that was developed for the satellite mission Foton-M1 to measure diffusion coefficients in liquid metals under microgravity (microg)-conditions. Thick Layer diffusion experiments were performed in the system Sn90In10 versus Sn under 1 g-conditions. For this system several microg-diffusion results are available as reference data. This combination provides a low, but sufficiently stable, density layering throughout the entire experiment, which is important to avoid buoyancy-driven convection. The experimental results were corrected for the influences of the shear-induced convection and mixing after the final shearing, both of which are typical for the shear cell technique. As the result, the reproducibility and the reliability of the diffusion coefficients in the ground-based experiments were within the limits of error of microg-data. Based on our results we discuss the necessary conditions to avoid buoyancy-driven convection.

Capillaries↗
PubMed2004

[A case of peripheral-type primitive neuroectodermal tumor arising in the dura mater at the frontal base].

A 7-year-old boy was admitted to our hospital because of headache and frequent vomiting. The patient was noted to have papilloedema and mild palsy of the right abducent nerve. Magnetic resonance image (MRI) revealed a large tumor in the frontal base with tumoral hemorrhage. Angiography showed the tumor was fed by anterior meningeal arteries. At surgery, the tumor was arising in the dura mater at the frontal base, and was removed totally. Histological examination showed the tumor to be composed of small cells with uniform round nuclei and minimal cytoplasm. Immunohistochemical studies were positive for MIC-2, NSE, C-KIT, vimentin, Class III-beta tublin and glycogen, but negative for NFP, synaptophysin, chromogranin A and GFAP. MIB-1 labeling index was 40-50%. The tumor was histologically confirmed to be peripheral-type primitive neuroectodermal tumor(pPNET). Following surgery, he underwent whole brain, whole spine and local radiation therapy(30 Gy in total respectively) and received two 5-day cycles of chemotherapy, consisting of intravenous administration of cisplatin 20 mg/m2/day, etoposide 60 mg/m2/day and IFOS 900 mg/m2/day. After these therapies, follow-up radiological examination showed there was no recurrence of the tumor for 24 months. Intracranial pPNET is rare. Ewing sarcoma and pPNET(ES/pPNET) is the designation given to a family of small round cell tumor arising in bone or soft tissues. Intracranial PNETs are devided into central nervous system PNET(cPNET) and pPNET. It is necessary that intracranial PNETs are divided into two types of PNETs because of different prognosis between these tumors. MIC-2 is a specific marker for pPNET/ES family and is useful in the differential diagnosis of these two types of tumors.

12E7 Antigen↗
PubMed2004

[Hemangioblastoma of the optic nerve growing like a dumbbell through the optic canal: case report].

We report a case of optic nerve hemangioblastoma in a 29-year-old man without a family history of von Hippel-Lindau disease or the other organ symptoms. He had progressive loss of vision and proptosis with a dull pain in his right eye. Magnetic resonance image (MRI) showed a gadolinium (Gd) enhancing solid tumor involving the prechiasmal right optic nerve with intraorbital extension. The tumor contained many signal voids of vessels and grew like a dumbbell through the right optic canal. Digital subtraction angiography demonstrated that the hypervascular tumor was fed by the ophthalmic artery and the orbital ramus of the middle meningeal artery. We succeeded in total resection of this hypervascular tumor by orbito-zygomatic approach. This tumor grew unusually like a dumbbell because it occurred in the optic nerve at the part of the optic canal. Histological examination revealed the tumor to be a characteristic hemangioblastoma. The postoperative course was uneventful. Supratentorial hemangioblastomas, especially optic nerve hemangioblastoma are extremely rare. This paper reviews the previous published cases and discusses their findings.

Adult↗
PubMed2003

Maxillary cancer in a child: a case report.

Cases with maxillary cancer are most frequently found in the 5th to the 7th decades of life, and then rarely occur in adolescence, even less so in a children. One does not expect to encounter this tumor in children, considering that most have a non-epithelial origin. However, we had a case of maxillary squamous cell carcinoma which appeared in a 12-year-old boy. He was initially considered to have sinusitis, and received conservative treatment for a while. After diagnosis, a combination therapy consisting of preoperative irradiation along intra-arterial administration of 5-FU and CBDCA was followed by total maxillectomy and primary reconstruction. Unfortunately about 2 months later, distant metastasis developed along with local recurrence, and the boy died about 1 year 6 months after the initial presentation. The clinical details of this rare case will be discussed in conjunction with some important considerations in dealing with this type of malignancy in a child.

Carcinoma, Squamous Cell↗
PubMed2003

A novel c-kit positive biphenotypic acute leukemia cell line, TMBL-1, carrying a p53 point mutation.

We established and characterized a c-kit positive cell line from the bone marrow of a patient with biphenotypic acute leukemia (BAL). The cell line, designated TMBL-1, carried a His-175 mutant p53. The immunophenotype of the primary leukemia cells at diagnosis was cytoplasmic CD3+, CD7+, CD13+, CD33-, interleukin-7 (IL-7) receptor+ and c-kit -. However, leukemia cells in relapse and TMBL-1 cells were CD33+ and c-kit +. Immunophenotypically, TMBL-1 is a BAL cell line that coexpresses T-lymphoid and myeloid markers which fulfill the criteria of the European Group for the Immunological Characterization of Leukemia. Stem cell factor (SCF), a key regulator of hematopoiesis signaling through c-kit, enhanced the proliferation of TMBL-1 cells. Direct sequencing revealed the conversion at codon 175 of the p53 gene in the TMBL-1 cells. Primary leukemia cells in relapse also carried the same point mutation but not at diagnosis. Moreover, TMBL-1 cells are sensitive to paclitaxel, which could induce p53-independent apoptosis. The biphenotypic features and p53 mutation may be associated with progression to a more malignant type. This cell line may provide new information on the role of SCF in the overlapping area between early T-lymphoid/myeloid cells, and help in the design of new therapies targeted towards p53 mutations.

Adult↗
PubMed2003

Hepatic stellate cells: unique characteristics in cell biology and phenotype.

Hepatic stellate cells (HSCs), a mesenchymal cell type in hepatic parenchyma, have unique features with respect to their cellular origin, morphology, and function. Normal, quiescent HSCs function as major vitamin A-storing cells containing over 80% of total vitamin A in the body to maintain vitamin A homeostasis. HSCs are located between parenchymal cell plates and sinusoidal endothelial cells, and extend well-developed, long processes surrounding sinusoids in vivo as pericytes. However, HSCs are known to be 'activated' or 'transdifferentiated' to myofibroblast-like phenotype lacking cytoplasmic lipid droplets and long processes in pathological conditions such as liver fibrosis and cirrhosis, as well as merely during cell culture after isolation. HSCs are the predominant cell type producing extracellular matrix (ECM) components as well as ECM degrading metalloproteases in hepatic parenchyma, indicating that they play a pivotal role in ECM remodeling in both normal and pathological conditions. Recent findings have suggested that HSCs have a neural crest origin from their gene expression pattern similar to neural cell type and/or smooth muscle cells and myofibroblasts. The morphology and function of HSCs are regulated by ECM components as well as by cytokines and growth factors in vivo and in vitro. Liver regeneration after partial hepatectomy might be an invaluable model to clarify the HSC function in elaborate organization of liver tissue by cell-cell and cell-ECM interaction and by growth factor and cytokine regulation.

Animals↗
PubMed2002

Visualization by comprehensive microarray analysis of gene expression programs during transdifferentiation of mesophyll cells into xylem cells.

Plants have a unique transdifferentiation mechanism by which differentiated cells can initiate a new program of differentiation. We used a comprehensive analysis of gene expression in an in vitro zinnia (Zinnia elegans L.) culture model system to gather fundamental information about the gene regulation underlying the transdifferentiation of plant cells. In this model, photosynthetic mesophyll cells isolated from zinnia leaves transdifferentiate into xylem cells in a morphogenic process characterized by features such as secondary-wall formation and programmed cell death. More than 8,000 zinnia cDNA clones were isolated from an equalized cDNA library prepared from cultured cells transdifferentiating into xylem cells. Microarray analysis using these cDNAs revealed several types of unique gene regulation patterns, including: the transient expression of a set of genes during cell isolation, presumably induced by wounding; a rapid reduction in the expression of photosynthetic genes and the rapid induction of protein synthesis-associated genes during the first stage; the preferential induction of auxin-related genes during the subsequent stage; and the transient induction of genes closely associated with particular morphogenetic events, including cell-wall formation and degradation and programmed cell death during the final stage. This analysis also revealed a number of previously uncharacterized genes encoding proteins that function in signal transduction, such as protein kinases and transcription factors that are expressed in a stage-specific manner. These findings provide new clues to the molecular mechanisms of both plant transdifferentiation and wood formation.

Asteraceae↗
PubMed2002

A case of angioglioma composed of astrocytoma with a papillary growth pattern: immunohistochemical and ultrastructural studies.

We report a case of a large cystic astrocytoma associated with arteriovenous malformation in the right cerebral hemisphere of a 16-year-old boy. Neuroimaging showed large abnormal vessels with flow voids and arteriovenous shunt around the cystic lesion. Histologically, the cyst wall was formed by abnormal vasculature and clusters of glial cells forming a papillary growth pattern. The abnormal vasculature consisted of dilated vein-like vessels and medium-sized arteries with incomplete media, and was diagnosed as an arteriovenous malformation. Immunohistochemically, glial fibrillary acidic protein (GFAP) decorated both the perikaryon and the processes of the glial tumor cells. They were negative for epithelial membrane antigen (EMA), cytokeratin, and S-100 protein. Ultrastructurally, the tumor cells were rich in intermediate filaments, and neither cilia, microvilli, nor ependymal rosettes were verified. Based on these morphological features and the low MIB-1 labeling index of 0.8%, the glial tumor was diagnosed as astrocytoma, Grade II, according to the World Health Organization (WHO) tumor classification. An association of glioma with various types of vascular anomalies has been designated as angioglioma. A unique feature of the present case, however, is a papillary growth pattern, which is not listed in the current WHO classification of brain tumors. The recognition of the occurrence of such cases would be important in differential diagnosis of papillary ependymoma and choroid plexus papilloma.

Adolescent↗
PubMed2002

Serum levels of endogenous thrombopoietin and granulocyte-colony stimulating factor in patients with acute or lymphoma type adult T-cell leukemia during multicycle chemotherapy.

Recent multidrug chemotherapy for adult T-cell leukemia (ATL) showed improved findings, however, these protocols often induced persistent myelosuppression. Among 67 patients with acute and lymphoma type ATL treated between January 1996 and December 1998, 42 patients died during this period and showed chemotherapy-induced myelosuppression. To characterize the relation between the severity of myelosuppression and the endogenous thrombopoietin (TPO) or granulocyte-colony stimulating factor (G-CSF) levels in ATL patients, we measured these hematopoietic factors using ELISA method. Nineteen patients with acute or lymphoma type ATL and 16 healthy individuals were examined. During thrombocytopenia, the serum TPO levels were significantly higher than that of controls (P < 0.0001) and were inversely correlated with the platelet counts (r = -0.687 P < 0.001). Later in the chemotherapy cycle, severe persistent thrombocytopenia occurred and TPO levels elevated and remained at a high level approximating the TPO levels of exogenous TPO administration (0.3 microg/kg body weight). On the other hand, the serum G-CSF levels with absolute neutrophil counts (ANC) below 0.5 x 10(9)/L were significantly higher than controls (P = 0.009) and inversely correlated with ANC (r = -0.382 P = 0.0034). However, G-CSF levels in six samples obtained after 6 h of G-CSF (100-150 microg per body) administration was approximately 50-fold higher than that in the neutropenic states. These findings suggested that G-CSF can effectively reduce the severity and duration of intensified chemotherapy-induced neutropenia and higher dose exogenous TPO (higher than 0.6 microg/kg per day) therapy may be required to enhance platelet recovery after intensive chemotherapy in ATL patients.

Adult↗
PubMed2002

Arsenic trioxide induces apoptosis in HTLV-I infected T-cell lines and fresh adult T-cell leukemia cells through CD95 or tumor necrosis factor alpha receptor independent caspase activation.

Arsenic trioxide (As2O3) has been reported to induce apoptosis in human T-cell leukemia virus type-I (HTLV-I) infected T-cell lines and fresh adult T-cell leukemia (ATL) cells and to induce G1 phase accumulation in HTLV-I infected T-cell lines. The present study aimed to clarify the pathway of As2O3-induced apoptosis in HTLV-I infected T-cell lines, MT-1 and MT-2, and fresh ATL cells separated from peripheral blood of patients with acute or chronic type ATL. Cells were treated up to 72 h at clinically tolerable concentrations of As2O3 (1-2 micromol/l) shown to be safe in patients with acute promyelocytic leukemia (APL). Activation of caspases 3, 8, and 9, loss of mitochondrial transmembrane potential and cleavage of poly (adenosine diphosphate-ribose) polymerase (PARP) were observed during As2O3 treatment. Furthermore, prior exposure to a broad-spectrum caspase inhibitor blocked As2O3-induced apoptosis but not G1 phase accumulation. While pre-treatment with a CD95 receptor-blocking antibody (Ab) or a TNF-alpha neutralizing Ab did not show such inhibitions in these cells. In conclusion, As2O3 induces apoptosis in HTLV-I infected T-cell lines and fresh ATL cells through CD95 or TNF-alpha receptor independent caspase activation.

Antineoplastic Agents↗
PubMedDate not supplied

Giant cell tumor at the lateral skull base.

Giant cell tumor is a bony tumor which primarily occurs in third to fourth decade after skeletal maturation. Usually, this tumor arises in the distal end of long bone and is quite rare in the head and neck region. We had a elderly female patient with giant cell tumor at lateral skull base of the left temporal bone without classic symptoms. Team approach with neurosurgeon was used to eradicate the tumor. The detail of this case in conjunction with treatment of giant cell tumor was reported while reviewing pertinent papers.

Biopsy, Needle↗