Search PubMed⌕ Search

Biomedical subjects

I Aoki

Publications and source records attributed to I Aoki.

At least 109 records · Page 6Linked to original sources
PubMed1993

Polyclonal B cell activation and antigen-specific stimulation in mice with chronic graft-versus-host reaction.

Primary chronic graft-versus-host reaction (GVHR) was induced in (C57BL/10 x DBA/2)F1 (BDF1) mice via the transfer of parental DBA/2 derived lymphocytes. A significant increase in the absolute number of IgM- and IgG-secreting cells was found in recipient BDF1 mice at 3 weeks post-transfer. The increase included B cells reactive with both self- and non-self-antigens, without being skewed toward the production of autoantibodies. Later in the disease process (approximately 6-8 weeks post-transfer), we detected an increased number of B cells that secreted antibodies reactive with a select subset of autoantigens in about 30% of BDF1 recipients (3 of 9 mice). These findings suggest that not only antigen-specific stimulation, which was detected in a late stage, but also initial polyclonal activation may account for chronic GVHR.

Animals↗
PubMed1993

Three-dimensional study of glomerular lesions in murine chronic graft-versus-host reaction by the quick-freezing and deep-etching method.

In murine chronic graft-versus-host reaction (GVHR), the immune complex composed of antoantibodies has been considered to induce human lupus-like nephritis. We prepared the replica membranes and immunoelectron-microscopic specimens of glomeruli of GVHR mice. The immunoelectron-microscopic examination revealed that immune deposits were noted mainly in the mesangial matrices and subepithelial area. The replica membranes showed various sizes of the deposits in the same portions. Moreover, fine fibrils around the deposits were strongly disrupted. Microfilaments were increased in the cytoplasm of podocytes and endothelial cells were slightly detached from glomerular basement membrane. In this model system, the immune deposits might play an important role in keeping the glomerular integrity.

Animals↗
PubMed1993

Genetic control of delayed-type hypersensitivity to chromium chloride.

Genetic control of delayed-type hypersensitivity (DTH) to chromium chloride antigen was studied in various strains of mice. Mice with I-Ab,d,f,k,r were high magnitude responders, whereas those with I-Aq,s were low magnitude responders. Studies with recombinant strains indicate that chromium chloride DTH may be influenced by the I-A region of H-2. DTH to chromium chloride is an antigen-specific response. We further revealed that response to chromium chloride does not cross-react with response to cobalt or nickel chloride. Also, transfer experiments using lymph node cells suggest that these responses are mediated by CD4+8-, Ia-T cells.

Animals↗
PubMed1993

[Clinical study of fluconazole for systemic fungal infections with hematological disorders].

Fluconazole (FLCZ) was administered orally or intravenously to 161 patients with systemic fungal infections complicated with hematological disorders and it was possible to evaluate clinical efficacies in 109 patients. Systemic fungal infections were documented in 48 patients and suspected in 61 patients. The overall clinical efficiency rates were 43.8% (21/48) in patients with documented fungal infections, and 55.7% (34/61) in patients with suspected fungal infections. Therefore, the overall clinical efficacy rate was 50.5% (55/109). Side effects were observed in 5 patients with an incident rate of 3.1% (5/161), but there was none of them was serious. These results indicate that FLCZ is an agent with good potential in treatment of systemic fungal infections in patients with hematological disorders.

Adolescent↗
PubMed1992

Determination of manidipine enantiomers in human serum using chiral chromatography and column-switching liquid chromatography.

A stereoselective and highly sensitive method using chiral chromatography and successive column-switching liquid chromatography is described for the determination of manidipine enantiomers in human serum. A human serum sample obtained after ingestion of manidipine was extracted twice with a mixture of n-hexane-diethyl ether under alkaline conditions. The enantiomers in the extract were separated on a chiral stationary phase column (Chiralcel OJ), and the effluents containing the respective enantiomers were collected. Each fraction was then analysed by column-switching liquid chromatography. The proposed stereoselective method offered high sensitivity: detection limits for both isomers were 0.2 ng/ml in human serum, both at a signal-to-noise ratio of 3. The method is suitable for the pharmacokinetic studies of manidipine enantiomers.

Administration, Oral↗
PubMed1992

A correlation between IgG class antibody production and glomerulonephritis in the murine chronic graft-versus-host reaction.

A graft-versus-host reaction (GVHR) was induced in (B10 x DBA/2)F1 (BDF1) and (BALB/c x A)F1 (CAF1) murine recipients by injection of their parental or B10.D2-derived spleen cells. The incidences of glomerulonephritis and autoantibody production were then correlated. All of the BDF1 mice that received DBA/2 spleen cells (termed DBA/2----BDF1) and 33% of the CAF1 mice that received BALB/c spleen cells (BALB/c----CAF1) developed glomerulonephritis. However, in other combinations (B10.D2----BDF1, A/J----CAF1) no significant glomerular lesions were observed. An analysis of antibodies by ELISA revealed that the groups with renal disease showed a significant polyclonal elevation of IgG class antibodies, including autoantibodies (anti-DNA, anti-MRBC, and NTA) and a conventional antibody (anti-TNP-KLH). No significant IgG class antibody production was observed in the groups that did not develop glomerulonephritis. Thus, it was suggested that an IgM to IgG class switch is important in the development of glomerulonephritis in GVHR. Other factors also appear to be involved. Only 33% of BALB/c----CAF1 developed glomerulonephritis, even though a level of IgG class antibody production was comparable to that observed in DBA/2----BDF1 in which 100% showed severe glomerulonephritis.

Animals↗
PubMed1992

Responsiveness of bone marrow erythroid progenitors (CFU-E and BFU-E) to recombinant human erythropoietin (rh-Ep) in vitro in multiple myeloma.

The responsiveness of bone marrow erythroid progenitors (CFU-E and BFU-E) to recombinant human erythropoietin (rh-Ep) was investigated in vitro in 21 patients with multiple myeloma to assess the clinical usefulness of rh-Ep in this disease. CFU-E and BFU-E assays were performed by methylcellulose culture methods. The myeloma patients were divided into two groups according to the percentage of plasma cells in the bone marrow (over 50% and under 50%). Among the patients with few plasma cells, some revealed normal CFU-E and BFU-E growth at 2 units of rh-Ep, and no further increase was observed even with an increasing dose of rh-Ep. Among the other patients, more than half demonstrated a good response to rh-Ep. Among the patients with a high percentage of plasma cells, some revealed no response to rh-Ep, but there were patients with a high percentage of plasma cells in the bone marrow who had a good response to rh-Ep. High doses of rh-Ep may be clinically effective in some patients with multiple myeloma independently of the level of plasma cells in the bone marrow.

Aged↗
PubMed1992

Glomerulonephritis induced by murine chronic graft-versus-host reaction.

Severe glomerulonephritis was induced successfully in (B10 x DBA/2)F1 (BDF1) mice by injection of parental DBA/2 lymphoid cells. The mice manifested typical nephrotic syndrome dying around 10 weeks post injection. Electron microscopical examination demonstrated electron dense deposits first in the mesangial matrix, then in the subepithelium compatible with immune complex glomerulonephritis. Subendothelial deposits were not observed. Immunofluorescent study revealed IgG deposition in the capillary wall and IgM in the mesangium early in the process. As the lesion progressed, both IgG and IgM were present in the mesangial area and along the capillary wall. Some glomeruli showed segmental mesangiolysis, suggesting that altered mesangial cells have a role in the development of glomerular change, which together with rise in serum anti-DNA antibody titer suggest that autoantibodies promote the glomerular lesions in this model system.

Animals↗
PubMed1992

[Clinical evaluation of sulbactam/cefoperazone for severe infections associated with hematological disorders].

The combination therapy of sulbactam/cefoperazone (SBT/CPZ) and piperacillin (PIPC) was evaluated in 49 patients with severe infections associated with hematological disorders. Clinical responses in 43 evaluable patients out of the 49 patients were excellent in 12, good in 18, thus, overall efficacy rate was 69.8% (excellent plus good). Efficacy rates of this combination therapy were 60% (3/5) for sepsis, 75% (21/28) for suspected sepsis, and 50% (4/8) for pneumonia. The efficacy rate was 71.4% (10/14) in patients with neutrophil counts less than 200/microliters; this combination therapy was highly effective even in the neutropenic patients. Transient increases in hepatic function test values were observed in 2 patients, but no other side effects were observed during the combination therapy. From these observations it appears that the combination therapy of SBT/CPZ and PIPC is a very useful empiric therapy for severe infections associated with hematological diseases.

Adolescent↗
PubMed1991

High-performance liquid chromatographic determination of lansoprazole and its metabolites in human serum and urine.

A simple and sensitive high-performance liquid chromatographic method with ultraviolet detection is described for the simultaneous determination of lansoprazole and its metabolites in human serum and urine. The analytes in serum or urine were extracted with diethyl ether-dichloromethane (7:3, v/v) followed by evaporation, dissolution and injection into a reversed-phase column. The recoveries of authentic analytes added to serum at 0.05-2 micrograms/ml or to urine at 1-20 micrograms/ml were greater than 88%, with the coefficients of variation less than 7.1%. The minimum determinable concentrations of all analytes were 5 ng/ml in serum and 50 ng/ml in urine. The method was successfully applied to a pharmacokinetic study of lansoprazole in human.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1991

Entropy principle for human development, growth and aging.

Entropy productions within nude subjects in respiration calorimeters are calculated from the corresponding energetic data obtained by Du Bois et al. (1952, J. Nutr. 48, 257-293.). The entropy production for men is constant at environmental temperatures from 24-34 degrees C. The metabolic entropy production comprises 98.6% of the total entropy production. The entropy production for women shows a minimum at 30 degrees C (the middle of the neutral zone), a small rise in the cold zone and a trend toward a rise in the warm zone; the average entropy production for women is 8.7% smaller than that for men. The entropy production rises from 0-2 years of age, and decreases rapidly from 2-25 years of age and then gradually to 85 years of age. The entropy production does not seem to achieve a minimum or a level in the lives of men and women. Based on these results, a three-stage hypothesis of entropy production in human life is proposed.

Aged↗
PubMed1991

Comparison of the amino acid and nucleotide sequences between human and two guinea pig major basic proteins.

By means of reverse-phase HPLC, 2 different proteins were obtained from apparently purified pig eosinophil major basic protein (MBP) and these proteins were named GMPB1 and GMBP2. It was revealed that these 2 components of MBP have similar molecular weights and pI values, although the amino acid compositions were slightly different. In the previous study, we cloned and sequenced GMPB1 cDNA. Here we obtained another clone by plaque hybridization using a screening probe synthesized by means of polymerase chain reaction. After sequencing, it became apparent that this clone corresponded to GMBP2. As in the case of GMBP1, the cDNA of GMBP2 encoded pre-proGMBP2 with 3 domains; signal peptide, acidic pro-portion, and mature GMBP2. By comparing the sequences of GMBP1 and GMBP2, it was revealed that the proteins were quite similar to each other. In addition, their sequences also resembled those of human MBP, especially in the basic domain of mature protein; but no such similarity existed in the pro-portion. Although the molecular weights determined by SDS-PAGE of guinea pig and human MBPs were 11,000 and 9,300, respectively, the calculated molecular weights of these 3 MBPs were all 13.8 kDa. The calculated pI values of GMBP1, GMBP2 and human MBP were 11.7, 11.3 and 11.6, respectively. By means of Harr plot analysis, it was revealed that the amino acid sequences, not only in signal peptides but also in the basic domains of mature proteins, were well conserved between guinea pig and human MBPs.

Amino Acid Sequence↗
PubMed1991

Sequencing and cloning of the cDNA of guinea pig eosinophil major basic protein.

Major basic protein (MBP) purified from guinea pig eosinophils elicited histamine release from rat peritoneal mast cells at concentrations higher than 3 micrograms/ml both in the presence and in the absence of extracellular Ca2+. After reverse-phase high-performance liquid chromatography, it was revealed that MBP was composed of two different proteins with quite similar molecular weights and pI values, although the amino acid compositions were slightly different. The partial amino acid sequence of one of these MBPs was determined and the primers for the polymerase chain reaction (PCR) were synthesized according to the partial amino acid sequence. Using these primers and the cDNAs obtained from guinea pig eosinophils, the PCR was carried out in order to synthesize the hybridization probe of MBP for screening the cDNA library. After screening with 8 x 10(5) clones, a positive clone, which encoded a full length of pre-proMBP, was obtained. According to the sequencing data of this clone, it was revealed that pre-proMBP was composed of 3 domains; signal peptide, acidic domain and mature MBP. The predicted pI value of mature MBP was 11.7, though that of proMBP was 7.8. The homology in the amino acid sequence between guinea pig proMBP and human proMBP was 49.4%, while guinea pig mature MBP was more homologous (58%) to human mature MBP.

Amino Acid Sequence↗
PubMed1991

Role of the cytoskeleton in Ca2+ release from the intracellular Ca store of rat peritoneal mast cells.

In order to study the role of the cytoskeleton in histamine release from mast cells, the effects of cytochalasin D, cholchicine and vinblastine on Ca2+ release from the intracellular Ca store induced by compound 48/80 were investigated by means of a video-intensified microscopy system. When the quin 2-loaded mast cells were stimulated by 0.35 micrograms/ml of compound 48/80, a rapid increase in intracellular Ca2+ was observed. At concentrations higher than 10(-6) M, both colchicine and vinblastine pretreatments significantly inhibited the increase in intracellular Ca2+ concentrations caused by compound 48/80, although cytochalasin D had no effect. When permeabilized mast cells were exposed to potassium-antimonate solution, microtubules became attached to the endoplasmic reticulum, where many dots of Ca-antimonate were observed; in some areas, the microtubules interconnected the endoplasmic reticulum and granules in the mast cells. From the results of the present study, it was assumed that microtubules play some important role in the processes leading to Ca2+ release from the intracellular Ca store.

Aminoquinolines↗
PubMed1991

The existence of filaments connecting the granules and the cell membrane in rat peritoneal mast cells.

SEM images of rat peritoneal mast cells showed that microtubule-like filaments seemed to penetrate the granules and project several branches just beneath the granular surface. Each granule appeared to be a cluster of microgranules. TEM observations frequently revealed microtubules connecting the granule surface to the subplasmalemmal network or to the adjacent granule surface and on some occasions, microtubules also appeared to penetrate the granule membranes. Moreover, TEM revealed that individual granules seemed to consist of a mass of microgranules, each 10-15 nm in diameter; freeze-fracture images showed similar configurations. These findings suggest that the microtubule-like filamentous structures in mast cells play a role corresponding to that of the open canalicular system in platelets.

Animals↗
PubMed1991

Contact sensitivity to mercuric chloride is associated with I-A region in mice.

Genetic control of contact sensitivity to mercuric chloride antigen was studied using various strains on inbred mice. Mice with class II Ab,d,f,s haplotypes showed a high magnitude of response, whereas those with class II Ak,q were low responders. These results indicate that mercuric chloride contact sensitivity may be influenced by the I-A region of H-2. Transfer experiments revealed that these responses might be mediated by L3T4+, Lyt-2- T cells. However Lyt-2+ T cells do not suppress the DTH response.

Animals↗