Search PubMed⌕ Search

Biomedical subjects

T Eto

Publications and source records attributed to T Eto.

At least 253 records · Page 14Linked to original sources

Alterations in circulating and cardiac tissue concentrations of brain natriuretic peptide in spontaneously hypertensive rats.

OBJECTIVE: This study was designed to investigate the modification of plasma and cardiac tissue brain natriuretic peptide concentrations in spontaneously hypertensive rats and Wistar-Kyoto rats in relation to those of atrial natriuretic peptide during the development of hypertension. METHODS: Blood pressure, tissue weight, and plasma and cardiac tissue atrial natriuretic peptide and brain natriuretic peptide concentrations were measured in conscious 5, 10, and 18 week old, spontaneously hypertensive, and in corresponding normotensive rats. Pharmacokinetics of atrial natriuretic peptide and brain natriuretic peptide were also examined. RESULTS: Plasma concentrations of both atrial natriuretic peptide and brain natriuretic peptide in hypertensive rats increased significantly with development of hypertension. The pattern was not in parallel, so that the brain natriuretic peptide/atrial natriuretic peptide ratio was high in spontaneously hypertensive rats. Concentrations of brain natriuretic peptide in the cardiac ventricle were already higher in hypertensive rats than in controls as early as 5 weeks of age, whereas atrial natriuretic peptide concentrations in the ventricle, predominantly in the left ventricles, and the highest brain natriuretic peptide/atrial natriuretic peptide ratio was in the left ventricles from 18 week old spontaneously hypertensive rats. Pharmacokinetics showed that the plasma half lives of atrial natriuretic peptide and brain natriuretic peptide were not different between the two strains. CONCLUSIONS: Although raised blood pressure stimulates both atrial natriuretic peptide and brain natriuretic peptide, production of brain natriuretic peptide in the ventricles is already increased in the prehypertensive stage, and in older hypertensive rats, it is more responsive to progression of hypertension than atrial natriuretic peptide. It is suggested that regulation of production and secretion of the two natriuretic peptides is not temporally coordinated during development of hypertension in this model.

Animals↗

Evaluation of leukaemic contamination in peripheral blood stem cell harvests by reverse transcriptase polymerase chain reaction.

A major issue in autologous blood stem cell transplantation (ABSCT) for leukaemia is whether peripheral blood stem cell (PBSC) harvests are less contaminated with leukaemic cells than bone marrow mononuclear cells (BMMNC). We compared leukaemic contamination in PBSC harvests and BMMNC, obtained simultaneously, by using reverse transcriptase polymerase chain reaction (RT-PCR) of leukaemia-specific chimaeric messenger RNA (mRNA), in three patients with Philadelphia chromosome (Ph)-positive acute lymphoblastic leukaemia (ALL), one with Ph-positive acute myelogenous leukaemia (AML), and two with acute promyelocytic leukaemia (APL). Our two-step PCR method employed 'nested primers' in the second step and can detect one leukaemic blast diluted into 10(6) HL-60 cells. In three of four patients with Ph-positive ALL and AML we detected leukaemic contamination in both PBSC harvests and BMMNC. In the remaining patient with ALL, both PBSC harvests and BMMNC were PCR-negative. Both PBSC harvests and BMMNC from one patient with APL were PCR-positive. In contrast, PBSC harvests from another patient with APL, whose BMMNC could not be obtained because of bone marrow necrosis, were PCR-positive after the first course of consolidation chemotherapy, but became PCR-negative after the second course. The present study does not support the hypothesis that PBSC harvests are less contaminated by leukaemic cells than BMMNC, but suggests that PBSC harvests are contaminated when BMMNC are contaminated.

Adult↗

Cytokine production by peripheral blood monocytes and T cells during haemopoietic recovery after intensive chemotherapy.

We studied the production of cytokines by peripheral blood monocytes and T cells during the period of haematological recovery following intensive chemotherapy. Twelve adults with haematological malignancies received consolidation chemotherapy of complete remission. Monocytes and T cells were collected during the phase of recovery from intensive chemotherapy, and were incubated for 24 h in a culture medium with 10% FCS. Concentrations of cytokines in the culture supernatant were measured with an enzyme-linked immunosorbent assay. During the recovery phase, concentrations of IL-6, G-CSF and IL-1 beta in the culture supernatant of the collected monocytes significantly exceeded those of the monocytes obtained from normal healthy subjects. Similarly, the concentrations of GM-CSF and IFN-gamma in the supernatant of recovery phase T cells significantly exceeded those of normal T cells. Plasma levels of these cytokines were also elevated. These data suggest that the monocytes and T cells may be activated in vivo to produce haemopoietic cytokines during haematological recovery, and that, during haematological recovery, the monocytes and T cells may be actively involved in the induction of haematopoiesis following the myelosuppression induced by chemotherapy.

Adolescent↗

Use of the conjugate of disulphated ursodeoxycholic acid with p-aminobenzoic acid for the detection of intestinal bacteria.

The disulphate ester of ursodeoxycholyl-p-aminobenzoic acid (PABA-UCDA) was synthesised and compared with PABA-UDCA for its use in detection of intestinal bacteria. This compound, PABA-UDCA disulphate, had characters in common with PABA-UDCA in that it was deconjugated by cholylglycine hydrolase to release free PABA and bacteria that split glycocholic acid deconjugated PABA-UDCA disulphate. Further, in rat experiments urinary excretions of PABA were measured for six hours after oral administration of 15 mg PABA-UDCA disulphate. Ten control rats excreted (mean (SE) 188.2 (13.6) micrograms of PABA; 10 rats with an intestinal stagnant loop excreted more (530.1 (30.1) micrograms; p < 0.001): whereas 10 rats in each of three groups pretreated by oral administration of various antibiotics excreted less (polymixin B+tinidazole, 4.9 (1.6) micrograms; kanamycin, 31.0 (4.7) micrograms; clindamycin 40.9 (5.5) micrograms; p < 0.001). By contrast with PABA-UDCA, PABA-UDCA disulphate was not actively absorbed from any part of the small intestine in everted gut sac experiments, and showed poor recovery from bile after its intraileal instillation in rats. This indicated that PABA-UDCA disulphate is a single pass type substance in the gut and its oral administration test reflects the sum of the activities of bacteria in the small intestine and colon. The disulphate was easily soluble in water and this allowed its application in an in vitro test involving PABA-UDCA disulphate incubation with intraperitoneal pus (PABA-UDCA disulphate incubation test) from patients with peritonitis. This test was carried out on six patients with peritonitis, and the severity of bacterial peritonitis was expressed quantitatively. From the results obtained PABA-UDCA disulphate was considered a good material to detect intestinal bacteria.

4-Aminobenzoic Acid↗

Increased plasma levels and effects of brain natriuretic peptide in experimental nephrosis.

Rat brain natriuretic peptide-45 (BNP-45) is a new cardiac hormone secreted into the circulation. In order to evaluate the pathophysiologic role of BNP in the nephrotic syndrome, we investigated the plasma levels and effects of BNP in adriamycin (ADR)-induced nephrotic rats. Plasma levels of BNP rose with time and more than doubled in 3 weeks after injection. Plasma levels of BNP correlated significantly with urinary protein excretion (UPrV) and urinary protein/creatinine ratio (UPrV/UcrV). When rat BNP-45 was injected as a bolus, hypotensive, diuretic, and natriuretic effects were completely abolished in nephrotic animals even at a high dose (2.0 nmol/kg), whereas the peptide produced marked UPrV with an increase in UPrV/UcrV. These results indicate that in ADR-induced nephrosis, BNP secretion from the heart is increased. Remarkable resistance to some hemodynamic and renal effects, while prompt proteinuric effects of BNP, may contribute to the sodium and water retention and urinary protein characteristic of this disorder.

Animals↗

Human colorectal carcinoma-specific glycoconjugates detected by pokeweed mitogen lectin.

Pokeweed mitogen (PWM) lectin, known to bind branched poly-N-acetyllactosamines, has a highly selective affinity for human colorectal carcinomas. We performed light microscopic (LM) histochemistry with PWM lectin on paraffin sections of human colorectal tissues. In histological sections, normal mucosae and adenomas with mild dysplasia exhibited negative reaction (0/10, 0/13, respectively) with or without neuraminidase pre-digestion, whereas adenomas with moderate dysplasia showed a small increase in PWM lectin reactivity after neuraminidase digestion (4/23). In contrast, we observed a high incidence of positive reactivity in colorectal carcinoma without neuraminidase pre-digestion (38/44). After digestion with neuraminidase, there was increased reactivity of colorectal carcinomas in situ (7/12) and invasive carcinomas (13/32). These results imply that human colorectal carcinomas consistently contain substantial amounts of PWM-reactive branched poly-N-acetyllactosamine glycoconjugates structures. We also compared the staining patterns of PWM lectin and monoclonal antibodies (MAb) directed to Lewis X (LeX) or Lewis Y (LeY) antigen. PWM lectin reactivity was largely confined to the apical membranes of carcinoma tissues. MAb-LeX or MAb-LeY immunoreactivity was seen on the apical membranes and in the cytoplasm of both adenomas and carcinomas. Therefore, histochemical studies with this lectin should be useful for identification of carcinoma tissues and analysis of glycoconjugates associated with colorectal carcinoma.

Adenoma↗

Pheochromocytoma associated with nocturnal hypertension.

Pheochromocytoma is often associated with paroxysmal hypertension. We report a 49-year-old woman with pheochromocytoma whose blood pressure (BP) was elevated regularly only at night. Plasma norepinephrine (NE) and neuropeptide Y (NPY) concentrations increased in parallel with the elevation of BP. After resection of the adrenal tumor, these circadian changes disappeared. Plasma NE and NPY, especially the former, from the tumor were considered to be the cause of this unusual fluctuation in BP.

Adrenal Gland Neoplasms↗

[Cytomegalovirus antigenemia in the differential diagnosis of pulmonary infiltrates after allogeneic bone marrow transplantation].

For the differential diagnosis of pulmonary infiltrates after bone marrow transplantation, cytomegalovirus (CMV) antigenemia was evaluated in 9 episodes of pneumonia which developed in 7 allogeneic marrow transplant patients between 9 and 495 days after transplant. The diagnosis of lung infiltration was made based on clinical findings including histological, cytological or microbiological examinations using bronchoalveolar lavage fluid specimens, sputum or lung tissue. The CMV antigen-positive leukocytes were detected with a direct immunoperoxidase technique using a peroxidase-labeled monoclonal antibody (HRP-C7) against CMV immediate early antigen. The episodes included 2 CMV pneumonias, 1 pneumocystis carinii pneumonia, 1 adenovirus pneumonia, 1 bacterial pneumonia, 1 bacterial and fungal pneumonia, 2 idiopathic pneumonias and 1 capillary leak syndrome associated with hyper acute GVHD. The CMV antigenemia became positive only in two patients with CMV pneumonia and the number of CMV antigen-positive leukocytes exceeded 10 per 50000 WBCs. The CMV antigenemia test required only 24 hours to obtain results. These observations suggest that the detection of CMV antigenemia is of great value in the differential diagnosis of pulmonary infiltrates in marrow transplant patients.

Adult↗

Cyclosporine combined with methylprednisolone or methotrexate in prophylaxis of moderate to severe acute graft-versus-host disease.

To evaluate the efficacy of cyclosporine (CYA) regimens in preventing moderate to severe acute graft-versus-host disease (GVHD), 25 patients received immunosuppressive therapy consisting of either CYA and methylprednisolone or CYA and methotrexate (MTX) and the incidence and severity of acute GVHD was compared. These patients had leukemia or myelodysplastic syndrome (MDS) and received bone marrow transplants (BMT) from genotypically HLA-identical siblings. The incidence of grade I-IV acute GVHD in patients on the CYA/methylprednisolone regimen was 64% (7 of 11) compared with 50% (7 of 14) in those on the CYA/MTX regimen. Five of 11 patients with the CYA/methylprednisolone regimen developed moderate to severe acute GVHD (grade II-IV), fatal in 3 cases. No patient on the CYA/MTX regimen developed moderate to severe acute GVHD. Engraftment was faster in the CYA/methylprednisolone group than in the CYA/MTX group. The incidence of toxicity observed soon after BMT was comparable between groups. The CYA/MTX regimen may be superior to the CYA/methylprednisolone regimen for preventing moderate to severe acute GVHD.

Acute Disease↗

Arterial pressure and its regulation in rats bred successively on low sodium diet.

To investigate the effects of long-term sodium restriction on mechanisms regulating cardiovascular function, Wistar rats at weaning (F0) were placed on a normal (0.4%) or low (0.05%) sodium diet. The first (F1) and second (F2) generations were derived from inbreeding within each group. The resting mean arterial pressure did not differ between the diet groups of F0 or F1 rats, but it was significantly lower in F2 rats on the low sodium diet. Plasma renin concentration was similar in the two groups in each generation, and the F2 rats on both diets responded to [Sar1, Ala8] angiotensin II with the same degree of decrease in arterial pressure. Plasma norepinephrine was not influenced by sodium intake in the F0 or F1 rats, but was significantly lower in F2 rats on the low sodium diet. The depressor response to hexamethonium was similar in the two F1 groups, while low sodium F2 rats exhibited a lesser response. These results suggest that rats bred successively on a low sodium diet have a suppressed sympathetic nerve function with no enhancement of the renin-angiotensin system, which in turn results in a lower arterial pressure.

Animals↗

Isolation and identification of C-type natriuretic peptide in human monocytic cell line, THP-1.

In a survey for unknown bioactive peptides in mammalian cell lines, we isolated peptides exhibiting a strong relaxant effect on chick rectum from a phorbol ester-supplemented culture medium of the human monocytic cell line, THP-1. The peptide was deduced to be a C-terminal 29-residue peptide derived from a human C-type natriuretic peptide (CNP) precursor. CNP mRNA was also detected in the THP-1 cells, and expression of CNP gene and CNP concentration in the culture medium was found to be highly augmented by the stimulation of phorbol ester. Production of CNP in THP-1 cells suggests that CNP also functions as a local regulator in the blood cell-vascular system, although CNP has previously been recognized as a neuropeptide functioning in the central nervous system.

Amino Acid Sequence↗

Organ distribution and characterization of porcine peptides (VIP, CGRP and PHI) that increase cAMP in rat platelets.

Using an assay for rat platelet cAMP, we investigated the organ distribution of peptides that increase cAMP in rat platelets in porcine tissues. Marked activity was observed in the duodenum, pancreas and brain. By analysis with reverse phase high performance liquid chromatography (HPLC), three major peaks of activity were observed in porcine tissues. The first peak was vasoactive intestinal polypeptide (VIP), and the second peak was calcitonin gene-related peptide (CGRP). The third peak of activity was isolated from porcine duodenum. By analysis with a gas phase sequencer and with an amino acid analyzer, this peptide was identified as peptide histidine isoleucine (PHI). In a glucagon-secretin family of neuropeptides, pituitary adenylate cyclase activating polypeptide (PACAP) significantly increased platelet cAMP levels in a dose-dependent manner; however, glucagon did not. These results suggest that not only VIP and CGRP but also PHI and PACAP act upon platelets, as well as vascular tissues.

Amino Acid Sequence↗

Isolation and characterization of peptides which act on rat platelets, from a pheochromocytoma.

An increase in the cellular concentration of cAMP leads to the inhibition of platelet aggregation. We have been investigating endogenous peptides which inhibit platelet function, using an assay which detects increase in platelet cAMP. Compared with the human adrenal medulla, a pheochromocytoma (PC) contained abundant peptides that elevate platelet cAMP. About 90% of the activity was found in the SP-III fraction which contained strongly basic peptides. From the SP-III fraction, peptides P-1, P-2 and P-3 were purified to homogeneity as endogenous peptides which elevated platelet cAMP. A gas phase sequencer was used to identify these peptides as follows: P-1 = vasoactive intestinal peptide (VIP); P-2 = calcitonin gene related peptide-I (CGRP-I); P-3 = CGRP-II. It is well known these peptides are potent vasorelaxants. VIP and CGRP-I significantly increased platelet cAMP levels 15- and 6-fold, respectively. These results suggest that VIP and CGRP-I and -II act upon platelets as well as upon vascular tissue.

Adrenal Gland Neoplasms↗

Intussusception of an appendiceal mucocele: report of a case.

A 66 year old Japanese female was admitted to our department for the examination and treatment of a mass in the cecum. She had experienced no symptoms or signs other than a positive test result for fecal occult blood. The mass in the cecum was confirmed by barium enema, colonofiberscopy and CT scanning. The presumptive diagnosis was a submucosal tumor of the cecum, however, a laparotomy subsequently revealed intussusception of an appendiceal mass. An ileocaecal resection with an ileocolic anastomosis was therefore performed and the mass was histologically diagnosed as a mucocele of the appendix. This patient is only the 24th case of intussusception of a mucocele of the appendix to be reported in Japan. A review of the available literature on this condition follows the case report.

Aged↗

Biological characteristics of CD7 positive acute myelogenous leukaemia.

We studied the biological characteristics of CD7+ acute myelogenous leukaemia (AML). We diagnosed nine out of 88 consecutive AML cases as CD7+ AML based on myeloperoxidase positivity and surface antigen expression. In eight of these nine cases more than 20% of leukaemic blasts were found to coexpress both CD7 and a myeloid-associated antigen, CD33, by a two-colour flow-cytometric assay, while in the remaining case more than 90% of blasts were positive for CD7 and myeloperoxidase. CD7+ AML was most frequently observed in M1 among AML subtypes according to the FAB classification. An early stage-specific antigen, CD34 was also expressed on leukaemic blasts from eight of these nine cases. Neither the T-cell receptor (TcR)-beta nor the TcR-gamma gene was clonally rearranged in any of the cases. We then studied the proliferative responses to stimulation by various growth factors. Among interleukin-3 (IL-3), granulocyte/macrophage colony-stimulating factor (GM-CSF), and granulocyte-CSF (G-CSF), IL-3 showed the strongest stimulatory effect on DNA synthesis and leukaemic blast colony formation in 8/9 and 6/8 CD7+ AML cases examined, respectively. On the other hand, the strongest stimulatory effect exerted by IL-3 on blast colony formation was observed in only six out of the 33 CD7- AML cases examined. Furthermore, CD7+ AML blasts could proliferate in response to stem cell factor (SCF); SCF alone showed stimulatory effects on blast colony formation (7/8 cases), and in 5/7 SCF-responding cases, stimulatory effects of SCF were more potent than those of IL-3. In addition, SCF enhanced blast colony formation synergistically with IL-3 in four of these seven cases. These data suggest that progenitor cells of CD7+ AML may possess the biological properties characteristic of immature haematopoietic stem cells.

Adolescent↗

Evaluation of atrial, ventricular and atrioventricular septal defects by cine magnetic resonance imaging.

Cine magnetic resonance imaging (MRI) was performed on 20 patients (mean age: 5.3 +/- 4.4 years) with atrial, ventricular, or atrioventricular septal defects for evaluation of cardiac structure and blood flow. Prior to cine MRI, electrocardiographically gated MRI using multislice acquisition was performed on all patients to localize optimal slice location. Cine-MRI was obtained with a 30 degrees flip angle, 15 msec echo time, and 30 msec pulse repetition time, on a 256 x 256 or 128 x 128 acquisition matrix. Abnormalities of cardiac structure were well defined in all patients by gated cardiac imaging. In 18 of the 20 patients, cine-MRI was able to detect shunt flow, visualized as a low intensity signal in comparison with the surrounding blood flow. Cine-MRI can provide not only accurate anatomy of cardiac structures but functional assessment of the cardiac chamber, wall topology and flow relations. Cine-MRI will become an important noninvasive technique for assessment of anatomy and physiology in congenital heart disease.

Abnormalities, Multiple↗