Biomedical subjects

S Itoh

Publications and source records attributed to S Itoh.

At least 199 records · Page 11Linked to original sources

PubMed1998

Growth factors in infant germinal matrix: relationship to extracellular matrix and cell adhesion molecules.

We examined the expression of selected growth factors, growth factor receptors, elements of extracellular matrix and cell adhesion molecules in the germinal matrix layer (GML) utilizing immunohistochemistry and reverse transcriptase polymerase chain reaction. At autopsy brain samples from 10 neonatal infants were used. Epidermal growth factor receptor (EGFR) was significantly expressed in the matrix cells. While transforming growth factor alpha and heparin-binding epidermal growth factor-like growth factor were found in the matrix cells or vascular wall as ligands, epidermal growth factor was not expressed. EGFR and its ligands are thought to be important factors for the maintenance of the matrix cells and cell-to-cell interactions. Insulin like growth factor I, its receptor Ibeta and tenascin were found in the stroma of the GML and periventricular region. Vascular endothelial growth factor and receptor Flk-1, laminin A and B2, fibronectin, collagen type IV and integrins such as beta3, alpha5beta1 and alphaVbeta3 were found mainly in or around the vascular wall indicating their important roles for vascularization. Transforming growth factor beta2 and its receptor II were expressed in the matrix cells and/or vascular wall suggesting a role in proliferation and/or regression of the vasculature. CD44 and Thy-1 were also expressed in the matrix cells.

Autopsy↗

PubMed1998

A wavelet transform-based ECG compression method guaranteeing desired signal quality.

This paper presents a new electrocardiogram (ECG) compression method based or orthonormal wavelet transform and an adaptive quantization strategy, by which a predetermined percent root mean square difference (PRD) can be guaranteed with high compression ratio and low implementation complexity.

Algorithms↗

PubMed1998

Autoantibodies against a 210 kDa glycoprotein of the nuclear pore complex as a prognostic marker in patients with primary biliary cirrhosis.

It has been reported that the presence of anti-nuclear antibody against a 210 kDa glycoprotein of nuclear pore complex (anti-gp210) is highly specific for primary biliary cirrhosis (PBC). The aim of the present study was to investigate the significance of anti-gp210, especially as a prognostic marker. The presence of anti-gp210 was ascertained in 113 patients with PBC and 162 controls by indirect immunofluorescence assay using HepG2 cells and immunoblotting analysis using nuclear extracts from HeLa cells. Anti-gp210 was detected in 25 of the 113 (22.1%) patients. None of the 162 controls was positive for anti-gp210. The appearance and titre of anti-gp210 in the patients with PBC did not vary from the time of diagnosis and through their clinical course. Anti-mitochondrial antibodies (AMA), including antibodies against pyruvate dehydrogenase complex, branched chain alpha-ketoacid dehydrogenase complex and alpha-ketoglutarate dehydrogenase complex, were not detected by enzyme-linked immunosorbent assay in five of the 113 (4.4%) patients with PBC. However, anti-gp210 alone was positive in one of these five patients. The difference in prognosis was statistically significant; patients with PBC positive for anti-gp210 died from hepatic failure more frequently than those who were negative (P < 0.01), although there were no statistically significant differences in the frequency of jaundice and the histological stage at the time of diagnosis between the two groups. We suggest that the presence of anti-gp210 is one of the independent prognostic markers able to predict, at the time of diagnosis, a poor outcome in patients with PBC.

Adult↗

PubMed1998

Characterization of a newly established human acinic cell adenocarcinoma cell line (HACC) originating from the salivary gland: morphological features and role of various growth factors on the growth of the HACC cell line.

Human acinic cell adenocarcinoma cell (HACC) line was established from the pleural effusion that contains metastatic tumor cells of acinic cell adenocarcinoma of papillary and microcystic type originating from the parotid gland. The HACC cells grew in an adherent monolayer with a doubling time of 66 h. Implanted tumor of SCID mice revealed similar histological findings to that of the primary tumor. The HACC cells produced mucin and expressed epithelial markers as well as alpha1-antitrypsin and lysozyme, whereas salivary peptide P-C was expressed in cultured HACC cells but not in the primary and implanted HACC cell tumors. S-100 protein was also expressed in both the primary tumor and HACC cell line. Neither amplification of common oncogenes nor expression of p53 was observed. The receptor for epidermal growth factor (EGF) was expressed, indicating EGF and transforming growth factor-alpha (TGF-alpha) enhanced the growth of the HACC line. Unexpectedly, tumor necrosis factor-a (TNF-alpha) also enhanced the growth of the HACC line significantly. However, there was no evidence of autocrine growth using these growth factors. In contrast, TGF-beta1 inhibited the growth of the HACC cell line through apoptosis. The HACC cell line has features similar to both acinar and intercalated ductal cells of the salivary gland. Epidermal growth factor, TGF-alpha and TNF-alpha are potential growth factors for the HACC cell line. The HACC cell line may be a good model for studying the biological behavior of salivary gland neoplasms.

Animals↗

PubMed1998

Effect of 26,26,26,27,27,27-Hexafluoro-1,25-dihydroxyvitamin D3 on the expression of vitamin-D-responsive genes in vitamin-D-deficient mice.

26,26,26,27,27,27-Hexafluoro-1,25-dihydroxyvitamin D3 (ST-630) is a newly developed agent to maintain the levels of calcium and phosphorus in blood. Herein, we investigated the effect of this compound on the expression of vitamin-D-responsive genes in vitamin-D-deficient mice. ST-630 was more effective than 1, 25-dihydroxyvitamin D3 [1,25(OH)2D3] with respect to the induction of Cyp24 and calbindin-D9k mRNAs in the kidney and in the small intestine. Moreover, the increase in mRNA levels of vitamin-D-responsive genes induced by ST-630 lasted longer than that induced by 1,25(OH)2D3. These results indicate that ST-630 was more effective in inducing Cyp24 and calbindin-D9k gene expression than 1, 25(OH)2D3 when both compounds were injected into vitamin-D-deficient mice.

Animals↗

PubMed1998

Purification and characterization of recombinant human granulocyte colony-stimulating factor (rhG-CSF) derivatives: KW-2228 and other derivatives.

Various derivatives of recombinant human granulocyte colony-stimulating factor (rhG-CSF) have been overproduced in Escherichia coli with the strong, inducible trp promoter. A derivative designated as KW-2228 in which the amino acids were replaced at five positions showed more potent granulopoietic activity and stability than those of wild-type both in vitro and in vivo. The purification involved a sequential renaturation process and three-step chromatography. Refolding succeeded in very high yield using a urea system. The purity of KW-2228 was greater than 99% as measured by SDS-PAGE and HPLC analysis. According to circular dichroism and nuclear magnetic resonance spectroscopy, rhG-CSF and KW-2228 have very similar conformations. This suggests that the substitution of five amino acids does not appreciably change the conformation of hG-CSF. KW-2228 ([Ala1, Thr3, Tyr4, Arg5, and Ser17]-hG-CSF) and derivative A ([Ala1, Thr3, Tyr4, Arg5]-hG-CSF) are easily crystallized and they show similar in vitro activity. On the other hand, neither rhG-CSF nor derivative B ([Ser17]-hG-CSF) are crystallized under the same conditions. Thus, the four amino acid substitution (Ala1, Thr3, Tyr4, Arg5) of the N-terminal sequence may facilitate crystallization. The change of Cys17 to Ser may not influence the stability and activity of hG-CSF.

Amino Acids↗

PubMed1998

Direct observation of t-butyl alcohol frozen and sublimated samples using low-vacuum scanning electron microscopy.

Frozen biological specimens in t-butyl alcohol were examined under a low-vacuum environment in a "wet SEM" or "variable pressure SEM (scanning electron microscope)" equipped with a cooling stage and highly sensitive backscattered detector of the YAG type. After fixation with glutaraldehyde and osmium tetroxide, rat tissue blocks (tracheae and kidneys), and cultured human carcinoma cells were dehydrated with a graded series of t-butyl alcohol. The specimens were directly frozen on the cooling stage at -10 degrees C, evacuated to 20 Pa in the specimen chamber, and observed by detecting backscattered electrons at accelerating voltages of 5-6 kV. The images became clearer 20 min after the vacuum reached 20 Pa and revealed had good quality by 30 min, probably because t-butyl alcohol was sublimated during the time. The cilia of tracheal ciliated cells, end-feet of the podocytes of the renal glomerulus, and processes of cultured cells were clearly observed without any serious preparation artifacts. Since the low-vacuum SEM of t-butyl alcohol frozen samples is both simple and provides high imaging quality, it is expected to be useful in a variety of biological fields such as the rapid pathological diagnosis.

Animals↗

PubMed1998

[Retroperitoneal Castleman's disease occurred around the bilateral upper ureters. A case report].

A 45-year-old woman with a history of right regional dull pain was referred to our hospital for evaluation of right hydronephrosis. CT and MRI showed a solitary mass (1 x 1 cm, L1-L2 level) at the right upper ureter. Laboratory data were within the normal range. A right nephrectomy was carried out under a clinical diagnosis of primary right ureteral tumor. The pathohistological diagnosis of surgical specimen was plasma cell type of Castleman's disease. One year after surgery, the patient was rehospitalized for azotemia and left hydronephrosis. Abdominal CT revealed a solitary mass (1.5 x 1.5 cm) located at left upper ureter similar to that on her right side. We diagnosed that the mass lesion was due to asynchronous Castleman's disease, so we performed steroid therapy. After the treatment, mass had disappeared. The patient is uneventful for two years. This is the first case reported in the Japanese literature describing Castleman's disease occurred around the bilateral upper ureters.

Castleman Disease↗

PubMed1998

[A study of post-operative delirium in elderly patients].

We investigated the post-operative delirium in elderly patients of over 65 years of age. This investigation consisted of two studies, a prospective study and a retrospective study. In the prospective study, we evaluated the incidence of post-operative delirium and the incidence of post-operative delirium was estimated pre-operatively using State-Trait Anxiety Inventory (STAI) and Mini Mental State Examination (MMSE) in 24 patients scheduled for elective surgery under general anesthesia in the period from Nov. 1995 to Oct. 1996. In the retrospective study, we selected patients with post-operative delirium from 1600 patients who had undergone scheduled and emergency operation under general anesthesia in the same period as in the prospective study and analyzed the incidence of post-operative delirium and background of these patients. Twenty four patients in the prospective study were excluded from the retrospective study. In the prospective study, although post-operative delirium was observed in 2 cases (8.3%), no specific changes were observed in anxiety state and the ability of recognition. In the retrospective study, post-operative delirium was observed in 22 cases (1.37%). In these patients, several factors such as blood transfusion, emergency operation, dehydration, thrombosis of the superior mesenteric artery, history of ischemic heart disease, brain infarction and atrial fibrillation were thought to be major risk factors triggering post-operative delirium. In this study we could not conclude that STAI or MMSE are useful to estimate the incidence of post-operative delirium preoperatively. However, our result suggests that we should be careful about the incidence of post-operative delirium in elderly patients with pre-operative risk factors as mentioned above.

Aged↗

PubMed1998

[Successful removal of a giant ball thrombus in the left atrium in an aged patient with unusual course].

A case of left atrial ball thrombus associated with severe mitral stenosis was reported. This male patient, aged 78, came in the chief complaint of leg and facial edema. An echocardiographic examination revealed the presence of mitral stenosis and floating giant ball thrombus in the atrium. He suffered from acute thromboembolism in his right leg six years ago and had been treated with anticoagulant since then. Despite this a floating giant ball thrombus was observed. Emergency operation including mitral valve replacement and thrombectomy was successfully performed. Thrombus formation in the left atrium is not uncommon but it is very rare to encounter in patients receiving anticoagulant therapy. To manage these patients well, meticulous attention must be paid during induction of anesthesia, intra-operative procedures, perioperative care, and operative position.

Aged↗

PubMed1998

[Hemophagocytic syndrome due to miliary tuberculosis in the course of aplastic anemia].

We report a 63 year-old female with aplastic anemia (AA) who was complicated with hemophagocytic syndrome induced by systemic miliary tuberculosis. Two years before admission to our hospital, she was diagnosed as AA and had been treated with granulocyte colony-stimulating factor, erythropoietin and methenolone acetate. In May, 1996, She was transferred to our hospital because of high fever and exacervation of pancytopenia. She showed severe pancytopenia, and an increase in macrophages showing remarkable erythrophagocytosis and decrease in hemopoietic cells in the bone marrow. In initial examination, high titer of IgM antibody to herpes simplex virus type I was identified and methylprednisolone pulse therapy was started under the diagnosis of virus associated hemophagocytic syndrome. Ten days later, however, she died for intestinal hemorrhage followed by multiorgan failure. In autopsy, multiple epitheloid cell granulomas with acid-fast bacilli were found in bone marrow, lungs, liver, spleen and kidneys.

Anemia, Aplastic↗

PubMed1998