Search PubMed⌕ Search

Biomedical subjects

C Itoh

Publications and source records attributed to C Itoh.

At least 37 records · Page 2Linked to original sources
PubMed1999

A Fe(3+)/DNA complex induces an anti-human immunodeficiency virus factor(s) in CD4+ lymphocyte cell lines.

Numerous cytokines and chemokines are involved in inflammatory and immune response. Whereas some of them inhibit virus replication in vitro directly or increase the patients' T4-lymphocyte level, others effects are not so clear. Using human immunodeficiency virus (HIV) and cell cultures we have studied the antiviral effect of complexes of salmon DNA with metals and of a new factor(s) (antiviral factor, AVF) induced in cells by the complexes. The Fe3+/DNA complex possessed the highest antiviral activity. It was found that MT-2, MT-4, CEM and Jurkat cells treated with the complexes secreted AVF which inhibited the replication of nine HIV-1 isolates, was noncytotoxic and stimulated cell proliferation. AVF did not inactivate HIV. The molecular mass analysis of AVF showed that its antiviral activity is associated with its fraction of M(r) of 3 K. Reverse transcription-polymerase chain reaction (RT-PCR) analysis of mRNA from MT-4 cells treated with the complexes showed an increase in the the expression of genes for interleukin-1 alpha (IL-1 alpha), tumour necrosis factor alpha (TNF-alpha) and TNF-beta while expression of genes for IL-1-beta, IL-2, IL-4, IL-6, IL-8. IL-10, IL-12; 35p, 40p, IL-13, GMCSF, GSF and RANTES was not detected at all. However, the anti-HIV activity of the cell culture supernatant in vitro cannot be explained by mere presence of the inflammatory substances mentioned above, because they do not possess such activity and their M(r) is higher than that of AVF. Our findings raise the possibility that AVF(s) may be involved in the mechanism of cell resistance against HIV.

Animals↗
PubMed1998

Correlation of histologic morphology and tumor stage with molecular genetic analysis using microdissection in gastric carcinomas.

Precise correlation of histomorphology with the results of molecular genetic analysis is difficult in gastric cancer tissue composed of intestinal and diffuse types. A novel microdissection procedure was applied to correlate p53 and APC allelic loss with histologic type and tumor stage (mucosal vs. invasive cancer) in formalin-fixed, paraffin-embedded specimens of 25 gastric cancers. In addition, mucosal and invasive lesions were dissected from each of 11 invasive gastric cancers to study progression, and allelic loss of the p53 and APC genes was assessed. The p53 gene underwent loss of heterozygosity (LOH) in 4 of 4 informative cases of intestinal-type gastric cancer with mucosal lesions associated with invasion. By contrast, no p53 LOH was found among 6 informative cases with mucosal cancer. LOH of the APC gene in both intestinal and diffuse types of cancer was detected in 4 of 7 and 5 of 6 informative cases, respectively. These data suggest that allelic deletion of the p53 gene in intestinal-type gastric carcinoma predicts the invasive potential of mucosal cancer, and that inactivation of the APC gene plays a role in the genetic tumorigenesis of both intestinal and diffuse types of gastric cancer. Microdissection can correlate genetic alterations with histologic morphology in gastric cancer.

Adenocarcinoma↗
PubMed1997

Electrocardiographic nature of restored sinus rhythm after Cox maze procedure in patients with chronic atrial fibrillation who also had other cardiac surgery.

OBJECTIVE: To characterise heart rate variability and high frequency components of restored sinus rhythm after the maze procedure. The maze procedure for chronic atrial fibrillation may prevent thrombotic events and improve the quality of life. However, the electrocardiographic nature of restored sinus rhythm after the maze procedure has not been fully elucidated. PATIENTS AND METHODS: Between March 1993 and August 1995, 104 consecutive patients undergoing the maze procedure in combination with other cardiac surgery were studied. There were 100 long-term survivors (78 with mitral valve disease, 9 with aortic valve disease, 8 with congenital heart disease, and 5 others). Twenty age-matched patients with mitral valve disease who were in normal sinus rhythm preoperatively were enrolled as a control group. 30 days after surgery, the presence of arrhythmias and the circadian changes of heart rate variability were estimated by ambulatory electrocardiographic monitoring and the filtered P duration was evaluated by signal-averaged electrocardiogram. RESULTS: Restoration of sinus rhythm was observed in 73 of 100 cases. Subjects were classified into three groups according to their postoperative ambulatory electro-cardiographic monitoring findings: patients in group 1 (n = 73) (1a: 58 regular sinus rhythm; 1b: 15 sinus rhythm with frequent premature atrial contractions (> 1000/day); patients in group 2 (n = 21) still had persistent atrial fibrillation; and patients in group 3 (n = 6) required permanent pacemaker implantation because of sick sinus syndrome. The success rate of restoration of sinus rhythm was 88.3% if left atrial diameter was small (< 65 mm). Circadian changes in the low frequency to high frequency power ratio in group 1a were significantly diminished compared with control group (P < 0.01). Furthermore, the filtered P duration in group 1a (150 (20) ms) and group 1b (158 (23) ms) were longer than in the control group (122 (11) ms) (P < 0.01). CONCLUSIONS: The maze procedure may result in a decreased sinus response and non-uniform transmission of impulses in the atrium.

Adult↗
PubMed1997

Two molecular species of oxytocinase (L-cystine aminopeptidase) in human placenta: purification and characterization.

Two different forms of oxytocinase (L-cystine aminopeptidase, CAP; EC 3.4.11.3) were purified from the 9000 g and 105000 g precipitate fractions of human placenta homogenate by sequential chromatography on columns of hydroxyapatite, DE-32, nickel ion affinity, and Sephadex G-200. One species (CAP-I) purifed from the mitochondrial/lysosomal fraction migrated on sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis with an apparent molecular mass of 61 kDa; the other (CAP-II) from the microsomal fraction was composed of two subunits with molecular masses of 56 and 40 kDa. The molecular masses of CAP-I and CAP-II estimated by gel filtration were 64 and 97 kDa, respectively. The specific activities of the two species for S-benzyl-L-cysteine p-nitroanilide increased by 357- (for CAP-I) and 139-fold (for CAP-II) compared with the starting preparations. The optimal pH values toward the artificial substrate were approx. 7.4-8.0 for CAP-I and 6.8-8.0 for CAP-II. The Km and Vmax values toward oxytocin were 5.6 microM and 23.4 micromol/h/mg protein for CAP-I, and 38 microM and 15.6 micromol/h/mg protein for CAP-II. Both enzymes were inhibited by the metal-chelating agents, EDTA and o-phenanthroline, whereas they were specifically activated by addition of Co2+: CAP-I was more sensitive to these reagents than CAP-II. L-Methionine strongly inhibited CAP-I, while CAP-II activity was only slightly affected. CAP-II was more sensitive to amastatin than CAP-I. Thus, the two enzymes are quite distinct in their molecular nature and biochemical properties. They may play a regulatory role in the metabolism of oxytocin and other biologically active peptides in intact placenta.

Cystinyl Aminopeptidase↗
PubMed1997

[Angiotensin I-converting enzyme gene polymorphism and renal disease].

ACE inhibitor is known to have a therapeutic efficacy in renal diseases by reducing proteinuria and maintaining renal function. However, the relationship between ACE gene polymorphism and renal disease has not been fully elucidated. In this study, a 287 base pair(bp) I/D polymorphism of the ACE gene was examined with polymerase chain reaction(PCR) in 100 healthy subjects, 34 patients with chronic glomerulonephritis(CGN), 29 with chronic renal failure(CRF) and 25 with diabetes mellitus(DM) with(13) and without(12) nephropathy. We also measured serum ACE activity of these patients. ACE genotype and derived allele frequencies in each disease group did not differ significantly from those in healthy subjects. In all disease groups, values of serum ACE activity were higher in genotype DD than in genotype II. These findings suggest no significant association between I/D polymorphism of the ACE gene and renal disease. Further studies are needed to clarify these findings, considering renal function and type of renal disease.

Adult↗
PubMed1996

Hroth an orthodenticle-related homeobox gene of the ascidian, Halocynthia roretzi: its expression and putative roles in the axis formation during embryogenesis.

To obtain insight into the axis-forming mechanism in ascidian embryogenesis, Hroth, an ascidian counterpart of orthodenticle/otx, was isolated from Halocynthia roretzi and its expression in embryogenesis was examined by whole mount in situ hybridization. It was revealed that Hroth is expressed in both involuting mesoendoderm and anterior ectoderm during gastrulation while later expression is restricted to the sensory vesicle and anterior epidermis. Expression pattern of Hroth around gastrulation was compared with that of Hrlim, the ascidian LIM class homeobox gene that is known to be expressed during gastrulation. In the light of the present findings on the expression of Hroth, properties of the axis-forming mechanism in ascidian embryogenesis are discussed.

Amino Acid Sequence↗
PubMed1996

Detection of HIV-1 and HIV-2 antibodies among Chlamydia trachomatis infected pregnant women in Japan.

An anonymous unlinked HIV antibody test was conducted on 1632 Chlamydia trachomatis (C. trachomatis) antibody positive women from 10 institutes of 7 prefectures in Japan. All the sera were negative for both HIV-1 and HIV-2 antibodies. The result may support the suggestion that HIV prevalence is low among general population in Japan. Such a test as this study will be useful not only for developing a reliable HIV surveillance system but also for the study of sexual behavior of general population, since C. trachomatis infection is sensitive to reflect sexual contact.

Adult↗
PubMed1996

[Cell adhesion molecules on platelet].

Platelets are anucleated blood cells that play a fundamental role in the initiation of hemostasis. In addition to platelet adhesion to the extracellular matrix, aggregation or platelet-platelet interaction is a requisite event in hemostasis. Some glycoproteins on platelet membranes mediate adhesion platelets. The glycoprotein (GP) Ib/IX/V complex is important in platelet adhesion and the GPIIb/IIIa complex mediate platelet to platelet interaction. P-selectin is a member of the selectin family and is transferred from secretory granules to the surface of activated platelets. P-selectin may function to mediate the interaction between activated platelets and leucocytes. We reviewed structure, function, biological roles and clinical application of three platelet-associated adhesion molecules.

Animals↗
PubMed1995

An aminopeptidase activity from porcine kidney that hydrolyzes oxytocin and vasopressin: purification and partial characterization.

An aminopeptidase from porcine kidney, hydrolyzing oxytocin and vasopressin in vitro, was purified by chromatography on hydroxyapatite, DEAE-cellulose and nickel ion chelate gel and gel filtration on Sephadex G-100. The enzyme appeared to be a high molecular mass (M(r) 105,000) monomeric protein. It was sensitive to inhibition by metal chelator, o-phenanthroline. Cobalt ion and sulfhydryl activator, 2-mercaptoethanol, had activating effects, while p-chloromercuribenzoate, amino acids with large hydrophobic side chains, L-cystine and aminopeptidase inhibitors, bestatin and amastatin, had inhibitory effects on the enzyme activity. The enzyme hydrolyzed several aminoacyl p-nitroanilides, and had the highest specificity against S-benzyl-L-cysteine p-nitroanilide. The properties of the enzyme were distinct from those of well-characterized leucyl aminopeptidase (EC 3.4.11.1), membrane alanyl aminopeptidase (EC 3.4.11.2) and primate placental cystinyl aminopeptidase (EC 3.4.11.3).

Aminopeptidases↗
PubMed1995

[Detection of CD62P (GMP-140) on peripheral blood platelet membrane in various heart diseases].

The protein CD62P expressed on platelet surface membrane was measured by flow cytometry to evaluate its clinical significance. Whole blood contained 0.32% citrate from 64 patients with heart disease and 30 healthy adults were fixed with 0.1% paraformaldehyde. To 50 microliters of the fixed blood, 10 microliters of CD62 PE (Becton Dickinson) was added. After standing for 20 minutes at room temperature, the samples were washed and suspended in 1ml of PBS. Platelets were analyzed with Spectrum III (Ortho) flow cytometer. In healthy control, the percentage of platelets positive for anti-CD62P was 0.16 +/- 0.20 (mean +/- SD)%. Abnormal levels of CD62P were observed in 5 patients with unstable angina, 6 patients with acute myocardial infarction, 1 patient with old myocardial infarction, and 2 patients with mitral stenosis. These results show that activated platelets may play some roles in pathogenesis of heart disease though it is not fully clear yet.

Biomarkers↗
PubMed1995

Concentration of soluble vascular cell adhesion molecule-1 (VCAM-1) correlated with expression of VCAM-1 mRNA in the human atherosclerotic aorta.

BACKGROUND: Adherence of circulating monocytes and lymphocytes to arterial endothelium is detectable early in experimental and human atherosclerotic plaque formation. The purpose of the present study was to assess vascular cell adhesion molecule-1 (VCAM-1) mRNA expression and the properties of soluble VCAM-1 in patients with atherosclerotic aortic disease. METHODS: Thirteen patients with aortic disease (mean age 64 years) and 40 healthy volunteers (mean age 32 years) were included in the study. We investigated the expression of VCAM-1 mRNA in eight human aortic specimens obtained during surgery. Of these, two showed no evidence of atherosclerotic plaque formation [aortic dissection (n = 1) and annuloaortic ectasia (n = 1)], whereas six had demonstrable complex atherosclerotic formation [abdominal aneurysm (n = 5) and aortic dissection (n = 1)]. The RNase protection assay was performed using an alpha 32P-labeled 121 base pair VCAM-1 cRNA probe. We also measured concentrations of the soluble VCAM-1 using two-site enzyme immunoassays in 40 healthy volunteers and in 13 patients with abdominal and thoracic aortic aneurysms. RESULTS: In human samples, VCAM-1 mRNA expression was found to be higher in the six patients with complex atherosclerotic formation [optical density (OD), 0.71 +/- 0.14] than in the two patients with no evidence of atherosclerotic plaque formation (OD, 0.53 and 0.49). The concentration of serum soluble VCAM-1 was higher (850 +/- 298 ng/ml) in patients with aortic or thoracic disease than in the healthy volunteers (494 +/- 94 ng/ml). In addition, there was a relationship between VCAM-1 mRNA expression and the concentration of soluble VCAM-1 (y = 2088x-554, r2 = 0.73). CONCLUSION: VCAM-1 expression is higher in the human aorta in patients with atheromatous changes. Furthermore, concentrations of soluble VCAM-1 may provide important information about endothelial activation or in-vivo damage.

Adult↗
PubMed1995

[The newly developed algorithm for signal-averaging ECG of P wave].

Signal-averaged P waves are available to evaluate patients at risk for paroxysmal atrial fibrillation. We developed a new algorithm of P wave triggered signal-averaged ECG applied the cross-correlation technique. Subjects consisted of 13 patients with paroxysmal atrial fibrillation (PAF group) and 12 normal volunteers (NOR group). ECG signals were amplified (5,000 times), filtered with band-pass filter (60-300 Hz) and averaged about 500 beats. The root mean square voltage for the total filtered P wave (P-RMS) and the duration of filtered P wave (FPD) were measured and were compared with those parameters obtained by level-slice P triggered method and R triggered method. The value of P-RMS in the all subjects was significantly higher by the cross-correlation method than that by the level-slice P triggered method (264 msec.microV versus 235 msec.microV, P < 0.001). The value of FPD in the PAF group was also significantly longer by the cross-correlation method than that by the level-slice P triggered method (151 msec versus 146 msec, P < 0.05). In conclusion, the cross-correlation method is suited for assessing P waves by the signal-averaged ECG.

Algorithms↗
PubMed1995

[Laboratory medicine of lymphocytes].

Recently, many laboratory tests associated with lymphocytes and/or lymphocyte functions have been developed. Among them, cytokine determinations of various body fluids and cytokine production assays are most highlightened. As cytokine is an effector molecule in immunological network, cytokine production profile may indicate functional state of immune response and immunopathological process. On the basis of these understandings, we propose cytokine production assay of whole blood culture system.

Cytokines↗