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Biomedical subjects

K Iwabuchi

Publications and source records attributed to K Iwabuchi.

At least 217 records · Page 12Linked to original sources
PubMed1989

Strain differences in the early development of the thymus-dependent cells: precocity of T lineage cells in AKR mice as compared to those in C3H mice.

Early development of T lineage cells were compared between AKR and C3H mice by using two experimental strategies--neonatal thymectomy (NTx) and bone marrow transplantation (BMT)--between these two strains of mice. After NTx, AKR mice developed less wasting disease and showed better maintenance of several T cell functions. In addition, the response of neonatal spleen cells to PHA and ConA was much greater in AKR mice than in C3H mice. Further, when AKR mice were used as recipients of BMT, cell numbers recovered from thymuses between 2 and 7 weeks after reconstitution were consistently much greater (about 10 times greater) than those from chimeras where C3H mice were used as recipients, regardless of the donor strains of bone marrow cells. However, 4 weeks after BMT the proliferative responses to ConA were consistently higher in the donor-derived thymocytes from chimeras where AKR mice were used as bone marrow donors than in those from chimeras in which C3H were donors. The present findings suggest that these differences may be attributed to characteristics of recipient microenvironment (e.g., thymic stroma) which maintain developing thymocytes and supply them to the peripheral lymphoid tissue. Alternatively the differences may to some degree also be attributable to characteristics of the thymic progenitors themselves, which may determine the rates of maturation of thymocyte functions.

Animals↗
PubMed1989

A study on graft-versus-host reaction (GVHR) by Simonsen's splenomegaly assay. Cells and antigen systems involved in induction of GVHR.

Cells and histocompatibility antigen systems involved in graft-versus-host reactions (GVHR) were analyzed using Simonsen's splenomegaly assay employing various combinations of donor and F1 hybrid recipients mice. Most of the cells proliferating in spleens of mice undergoing GVHR were J11d+, and had histological features of cells of the hematopoietic lineage. The proportions of CD3+ T cells were decreased in the spleens. Disparity at minor histocompatibility determinants of AKR, I-E and H-2D regions between B10.A(4R) donors and (4R X AKR) F1 recipients evoked only negligible GVHR. On the contrary, disparity at H-2K and/or I-A regions appeared to be sufficient to permit induction of full GVHR. When surface markers of donor spleen cells were analyzed, it was shown that Thy-1+ and/or MEL-14+ cells caused a strong effect on GVHR. Further, either CD4+ or CD8+ T cell subset could induce significant GVHR. However, synergistic influences of these two T cell subsets on one another in GVHR were observed. The present results raise the possibility of using Simonsen's assay along with a number of reagents to identify the contribution of subsets of T lymphocytes and in analyzing precise contributions of cellular components from both donor and recipient, and also of the target antigen systems of the recipient that contribute to early events involved in GVHR.

Animals↗
PubMed1989

[Cerebral cysticercosis presenting as a solitary cyst. Diagnosis and treatment with CT-guided stereotactic biopsy--case report].

The patient, a 52-year-old male, experienced a generalized convulsive seizure. Computed tomography (CT) revealed a solitary, noncalcified cyst, 1 x 2 cm in diameter, in the left occipital lobe, without contrast enhancement. No other lesions were found in systemic soft tissues, skeletal muscles, or the eyes. A CT-guided stereotactic biopsy was performed through an occipital burr hole, and the diagnosis was cerebral cysticercosis. Although cysticercosis is still common in Mexico, Chile, and India, its occurrence has rarely been reported in Japan, especially since World War II. Intraparenchymal calcification and cystic lesions are common CT findings. However, in this case, a non-enhancing solitary cyst was the only CT finding. The authors review the literature and discuss the CT features and the usefulness of CT-guided stereotactic biopsy in the diagnosis and treatment of cysticercosis.

Biopsy↗
PubMed1989

Plasma glycosyltransferase activity after ABO-incompatible bone marrow transplantation and development of an inhibitor for glycosyltransferase activity.

Plasma glycosyltransferase activities were studied in eight patients after ABO-incompatible bone marrow transplantation. The ABO red blood cell type completely changed from the recipient type to the donor type; however, preexistent plasma glycosyltransferase activities of the recipient type did not change in seven of eight patients after marrow transplantation. Weak transferase activities of the donor type were observed in all of the patients after marrow grafting. One patient with acute and chronic graft-versus-host disease produced a very potent inhibitor that was active on both A- and B-transferase activities. Because this inhibitory activity was absorbed by a protein A-coupled Sepharose column, it was strongly suggested that this inhibitory activity was mediated by an IgG antibody for a transferase.

ABO Blood-Group System↗
PubMed1989

[The reappraisal study of the ultrastructure of Alzheimer's neurofibrillary tangles in three cases of progressive supranuclear palsy].

Progressive supranuclear palsy (PSP) is characterized by symptoms of disturbance of eye movement, nuchal rigidity, parkinsonism and subcortical dementia. Its pathology reveals that Alzheimer's neurofibrillary tangles (NFTs) are situated especially in the nuclei of basal ganglia and brainstem. It has been pointed out that NFTs observed in PSP are composed of straight tubules, the width of which is about 15 nm. This report is to reappraise the ultrastructure of NFTs observed in three cases of PSP. They are case 1; 69-year-old male, case 2; 62-year-old female and case 3; 65-year-old male. The clinical features of three cases were characterized by above-mentioned symptoms. Many NFTs were observed in brainstem of case 1 and 3. NFTs seen in brainstem of case 2 were in a small amount. In case 1 and 2, there were many NFTs in cerebral cortex, especially in parahippocampal gyri and other limbic areas. We examined the portions of frontal cerebral cortex, parahippocampal cortex, the basal nucleus of Meynert, oculomotor nucleus, substantia nigra, pontine nuclei and locus caeruleus of case 1, substantia nigra, red nucleus and inferior olivary nucleus of case 2, and Ammon's horn, globus pallidum, subthalamic nucleus, substantia nigra, oculomotor nucleus, pontine nuclei, locus ceruleus and inferior olivary nucleus of case 3. Ultrastructurally, NFTs of frontal cortex of case 1 consisted of twisted tubules and those of hippocampal and parahippocampal cortices of case 1 consisted of straight and twisted tubules, being observed separately in neurons. The NFTs of brainstem of case 1 and 2 were mainly composed of 12-17 nm straight tubules, and twisted tubules occasionally intermingled with straight components. In locus ceruleus of case 1, a single straight tubule could be seen in the bundles of twisted tubules. NFTs of case 3 were composed of only straight tubules, the width of which was about 15 nm. Twisted components were not observed in neurons of each nuclei of case 3. The characteristic ultrastructure of NFTs in PSP has been an appearance of straight tubules, however, twisted tubules were occasionally observed in this study. There are several case reports which demonstrated an appearance of both straight and twisted components. It is easily presumed that the process of aging takes part in the accumulation of twisted fibrils. However, it is now under consideration why twisted tubules are also observed in PSP. To summarize this study, the cases with many NFTs observed in widespread cerebral cortex may have a tendency to show both straight and twisted tubules.

Aged↗
PubMed1989

Long-term observation of immunologic reconstitution after allogeneic bone marrow transplantation: differences in recovery among functional T cell subsets.

A 27-year-old male with acute lymphoblastic leukemia in the first relapse received allogeneic marrow graft from an HLA-identical sister on April 28, 1978. We studied in vitro immunologic parameters such as T cell surface phenotypes, proliferative response to PHA and Con A; T cell suppressor and helper function for in vitro immunoglobulin production stimulated with pokeweed mitogen serially after the transplantation. Despite a low OKT4/OKT8 ratio for more than 5 yrs after marrow grafting, proliferative response to PHA recovered to normal 4 yrs and 9 months post-transplant. In contrast, proliferative response to Con A did not recover. T cell suppressor function induced by Con A had recovered at 3 yrs 6 months; however helper T cell function took longer to recover. These findings suggest differences in functional recovery of T cell subsets following allogeneic marrow transplantation.

Adult↗
PubMed1989

[Flow cytometric analysis of T lymphocyte subsets after human bone marrow transplantation using monoclonal antibodies and dual immunofluorescence].

Using monoclonal antibodies and a dual immunofluorescence technique, we studied the abnormalities of T lymphocyte subsets after human marrow transplantation. T lymphocytes bearing HLA-DR antigen increased both in patients with acute and chronic graft-versus-host disease (GVHD). Parallel to a decrease in CD4+ cells, a CD4+ 2H4+ subset decreased and gradually recovered with time while the percentage of CD4+ 4B4+ cells increased. A significant increase of CD8+ cells observed after marrow transplant corresponded mainly to an increase in CD8+ CD11- cells. Patients with chronic GVHD tended to have a higher proportion of CD8+ CD11+ cells. These results indicate abnormalities of T cell subsets among both CD4+ and CD8+ cells after marrow grafting.

Adolescent↗
PubMed1989

A study on type II collagen-induced arthritis in allogeneic bone marrow chimaeras.

In the present investigation, the incidence, day of onset and severity of type II collagen (IIC)-induced polyarthritis (CA) in allogeneic bone marrow chimaeras were compared. These chimaeras were prepared by using reciprocal combinations between DBA/1J (H-2q, Igh-1c, Hc1), which are highly susceptible to CA, and SWR/J (H-2q, Igh-1c, Hc0), which are CA resistant, strains of mice. The four kinds of chimaeras, [SWR----DBA/1], [DBA/1----DBA/1], [DBA/1----SWR] and [SWR----SWR], were shown to be full chimaeras. [SWR----DBA/1] and [DBA/1----DBA/1] chimaeras showed serum C5 antigens and most of these mice developed CA, even though severity of CA in [SWR----DBA/1] chimaeras was less than that in [DBA/1----DBA/1] syngeneic chimaeras. By contrast, [DBA/1----SWR] and [SWR----SWR] chimaeras completely lacked serum C5 and did not develop CA at all. However, most of these chimaeras produced considerable total IgG and IgG2a antibodies to IIC in the sera after immunization with the antigens, although differences in the serum levels of IgG2a antibodies were seen between [SWR----DBA/1] and [DBA/1----SWR] allogeneic chimaeras. The present results demonstrate directly a crucial role of complement cascade in the induction and development of CA and reveal that lymphoid cells of SWR mice potentially have the ability to develop CA. Differences in severity of the CA observed in some of these chimaeras, however, could not be readily explained by differences in C5 concentrations alone.

Animals↗
PubMed1989

[Anesthesia for aorto-coronary bypass graft surgery in children with Kawasaki disease].

We investigated anesthetic management of aorto-coronary bypass graft surgery (CABG) in the children who have coronary disease due to acute febrile mucocutaneous lymph node syndrome (Kawasaki disease). A retrospective observation was made on anesthetic management of 17 patients with Kawasaki disease. They were 13 boys and 4 girls and their ages ranged from 5 to 13 years. They underwent CABG during the past 10 years (1976-1986) in Tokyo Women's Medical College Daini Hospital. Induction of anesthesia was carried out with halothane-nitrous oxide-oxygen (GOF) in 16 patients and morphine-nitrous oxide-oxygen (GOM) in one patient. Anesthesia was maintained with GOF in 11 patients, and in 6 patients with GOF and narcotics. High-dose fentanyl was not used for anesthetic induction in children with Kawasaki disease. Pulse rate increased significantly after endotracheal intubation. Blood pressure increased after endotracheal intubation in 5 patients and after sternotomy in one patient. Hypotension developed in 2 patients. Coronary spasm did not occur during the all procedures. Control of blood pressure during CABG in children was easier than in adult patients. But the control of pulse rate offers a problem in anesthetic management of the children with Kawasaki disease.

Adolescent↗
PubMed1988

Bone marrow cells from allogeneic bone marrow chimeras inhibit the generation of cytotoxic lymphocyte responses against both donor and recipient cells.

When added to a mixed lymphocyte culture, bone marrow cells suppress the generation of CTL activity against H-2 Ag shared by the BM cells and the stimulator cells. These cells have been referred to as veto cells and are thought to play a role in maintaining self-tolerance. We analyzed the H-2 specificity of the suppression expressed by the veto cells from H-2 incompatible bone marrow chimeras, because lymphocytes of such chimeras had been shown to be tolerant to both donor and recipient Ag when tested by CTL responses. We found that the bone marrow cells of such chimeras which were featured by non-T and non-B cell characteristics inhibited the generation of CTL directed against either donor or recipient Ag, but not against third-party Ag. These observations suggest that in allogeneic chimeras the veto or veto-like cells alter the inhibitory specificity exhibited in the recipient microenvironment and indicate that these cells are directly involved in the induction and maintenance of self-tolerance.

Animals↗
PubMed1988

Three categories of the degenerative appearance of the human cerebellar dentate nucleus. A morphometric and morphological study.

This morphometric and morphological study demonstrates 3 categories (types A, B and C) of degenerative feature in the cerebellar dentate nucleus. Type A is characterized by neuronal loss, astrocytosis and granular and/or amorphous argyrophilic change around the neurons and neuronal processes, and this type was thought to be synonymous with the so-called grumose degeneration of the DN. Type B is characterized by extensive neuronal loss and astrocytosis without argyrophilic change, and it was considered that many diverse factors were responsible for type B. Type C features marked swelling of the neurons without neuronal loss, astrocytosis or argyrophilic change. The Purkinje cells were not involved in type A and C, but severely damaged in type B. Clinically, type A was observed in progressive supranuclear palsy and dentatorubropallidoluysian atrophy, type B extensively in many diseases including anoxic, toxic and infectious disorders, and type C in tardive dyskinesia manifesting with oral hyperkinesia. Types A and C may be more or less specific signs of degeneration of the dentate nucleus, whereas type B appears to be non-specific.

Adult↗
PubMed1988

Two necropsy cases of chronic encephalomyelitis: variants of Neuro-Behçet's syndrome?

Two necropsy cases of chronic encephalomyelitis of unknown aetiology are presented. Skin hyperreactivity occurred in both cases although there were no mucocutaneo-ocular symptoms. There was confluent perivenous necrosis with marked glio-mesenchymal reactions and persistent inflammatory changes, predominantly in the diencephalon and brain stem. These cases are clinico-pathologically analogous to Neuro-Behcet's syndrome.

Adult↗
PubMed1987

Localization of neutrophil adherence-inhibiting factor in guinea pig platelets.

The effect of constituents of guinea pig platelets on neutrophil adherence was examined. The platelet sonicate supernatant contained adherence-inhibiting activity which strongly inhibited neutrophil adherence to glass. When the platelet sonicate supernatant was treated with neuraminidase or trypsin, the adherence-inhibiting activity was significantly inhibited, suggesting that the adherence-inhibiting factor (AIF) is a glycoprotein. The subcellular fractionation experiments indicated that the AIF activity was present at about 40% in both the cytosol and granule fractions. From the Sephadex G-200 gel filtration analysis, AIF of cytosol fraction and granule fraction proved to be different molecules, with molecular masses of about 230 and 12 kDa, respectively. When platelets were stimulated with thrombin, about 20% of total AIF was released extracellularly without the release of the cytoplasmic enzyme lactate dehydrogenase. These results suggest the possibility that a biologically active substance, AIF, is released from platelets in response to stimuli and regulates neutrophil functions through interference with neutrophil adherence.

Animals↗
PubMed1987

A study on proliferative responses to host Ia antigens in allogeneic bone marrow chimera in mice: sequential analysis of the reactivity and characterization of the cells involved in the responses.

Irradiation bone marrow chimeras were established by reconstitution of lethally irradiated AKR mice with C57BL/10 marrow cells to permit serial analysis of the developing reactivities of lymphocytes from such chimeras, [B10----AKR], against donor, host, or third party antigens. We found that substantial proliferative responses to Ia antigens of the recipient strain and also to third party antigens were generated by the thymocytes obtained from the irradiation chimeras at an early stage after bone marrow reconstitution. The majority of the responding thymocytes had surfaces lacking demonstrable peanut agglutinin receptors and were donor type Thy-1+, Ly-2-, and L3T4+ in both anti-recipient and anti-third party MLR. In anti-host responses, however, Ly-2+ thymocytes seemed to be at least partially involved. This capacity of thymus cells to mount a response to antigens of the recipient strain declined shortly thereafter, whereas the capacity to mount MLR against third party antigens persisted. The spleen cells of [B10----AKR] chimeras at the same time developed a more durable capability to exhibit anti-host reactivities and a permanent capability of reacting to third party allo-antigens. The stimulator antigens were Ia molecules on the stimulator cells in both anti-recipient and anti-third party MLR. The responding splenocytes were of donor origin and most of them had Thy-1+, Ly-1+2-, and L3T4+ phenotype.

Animals↗
PubMed1987

Nasu-Hakola's disease (membranous lipodystrophy).

An autopsy case of Nasu-Hakola's disease (membranous lipodystrophy) is reported. A 43-year-old Japanese man, whose parents were not consanguineous, had been suffering from frequent long bone fractures since the age of 10. Neuropsychiatric symptoms, which were characterized by euphoria, disturbance of attention and dementia, appeared at his thirties and generalized and/or localized seizures and apallial syndrome at the later stage. The neuropathology revealed diffuse leukoencephalopathy of the cerebrum. The peculiar aspects in this case were membranocystic changes in the lungs [Yagishita et al. Virchows Arch [A] 408:211-217 (1985)], diffuse degeneration of the cerebral cortex, chiefly in frontal and temporal lobes, and many axonal spheroids throughout the cerebral cortex. The ultrastructure of spheroids in the cerebral cortex demonstrated aggregations of mitochondria, dense bodies and minute concentric bodies and a small amount of neurofilaments.

Adult↗
PubMed1987

Response of pancreatic tumor to intraoperative radiotherapy: medical imaging and pathologic system approach.

For analyzing the local reaction of pancreatic carcinoma to electron intraoperative radiotherapy, successive computed tomography scanning for tumor volumetry was employed, together with surgical clip localization for tumor area using orthogonal x-rays. Soon after radiotherapy the tumor volume and clipped tumor region began to decrease. After a certain interval, computed tomography volumetry revealed that the irradiated tumor had started to increase in size again, whereas the clipped area had not. Autopsies demonstrated that the increase related chiefly to cancer regrowth outside the primary radiation field.

Aged↗
PubMed1987

An epitope on class II antigens that is maintained across species barriers and important in immunologic functions.

Serological, functional, and chemical analyses of murine class II antigens were performed using a unique monoclonal antibody, 1E4, which was obtained from a rat-mouse hybridoma. 1E4, which is specific for a monomorphic determinant on HLA-DR antigens in humans and a polymorphic determinant on RT1-Da antigens in rats, detected class II antigens on the cells from mice carrying H-2 haplotypes of b, d, p, q, u, v, k, j, r, but not those with f or s haplotypes. Analysis of two-dimensional gel electrophoresis revealed that 1E4 monoclonal antibody recognized at least Ek/b, d, k and Ab, d molecules. 1E4 blocked the T cell proliferative responses to beef insulin and TGAL in B10 and BALB/c mice, as well as proliferative responses to GLT in BALB/c mice and to PPD in C3H/He mice, as had been demonstrated in other species. Furthermore 1E4 inhibited MLR to stimulator cells that expressed Ab, d or Ek/b, k, d molecules. Taken together, these findings indicate that an epitope detected by 1E4 on class II antigens has been well preserved across species barriers. This epitope may play a major role or be closely related to the functional site that is involved in recognition of nominal antigens by T cells.

Animals↗