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Biomedical subjects

Y Nishimura

Publications and source records attributed to Y Nishimura.

At least 739 records · Page 41Linked to original sources
PubMed1992

Idiopathic necrosis of the femoral epiphyseal nucleus in rats.

To study the cause of osteonecrosis of the femoral head in spontaneously hypertensive rats, the site and mechanism of the occlusion of the blood vessels feeding the femoral head were investigated histologically and microangiographically. Tracing the blood vessels using serial sections revealed that the lateral epiphyseal vessels disappeared immediately before entry into the ossific nucleus. As the reparative process advanced, the blood vessels from the lateral side of the head entered the ossific nucleus again. To investigate the relationship between osteonecrosis and mechanical stress on the femoral head, some treatments to reduce mechanical stress were applied, and the frequency of the femoral head lesions, such as osteonecrosis, disturbed ossification, and abnormality of the growth plate, was compared among the groups of treatments for stress relief. The incidence of femoral head lesions was found to be directly proportional to the mechanical stress working on the area, as was evident from a decrease in the incidence of osteonecrosis as a result of reduction of mechanical stress. Thus, the obstruction of the vessels in the lateral part of the femoral head might result from the breakdown of cartilage caused by the mechanical stress on the femoral head.

Angiography↗
PubMed1992

[Contribution of genetic factors to RA].

Multiplex families of rheumatoid arthritis (RA) and concordance of the development of RA in monozygotic twins strongly suggest the relationship of genetic factor to the onset of RA. Among many genetic markers, HLA shows the strongest association with RA and association between RA and HLA-DR4 has been reported in many ethnic groups. DNA typing of HLA class II genes revealed that DRB1 * 0405 (Dw 15) is the most susceptible DRB1 allele for RA in the Japanese. The particular epitope sequence at the third hypervariable region (position 70-74, and 86) and DR beta chain, expressed with the structure of the DR4 molecule seems to be important for the susceptibility to RA.

Arthritis, Rheumatoid↗
PubMed1992

[A case of coexistent bronchogenic carcinoma with pulmonary tuberculosis].

A 79-year-old housewife complaining of shortness of breath presented with a LUL mass lesion on chest roentgenogram. Bronchofiberscopic biopsy and curettage revealed adenocarcinoma as well as acid-fast bacilli of Gaffky-4. Further investigations showed increased ESR, CRP levels and positive RF. PPD skin test was positive measuring 55 x 43 mm. A left upper lobectomy with mediastinal lymph node dissection was performed. The mass was in S1+2 and measured 2.7 x 2.5 x 1.5 cm. Histologically caseaous necroses and spotted granulomas of tuberculosis were surrounded by bronchioloalveolar cell carcinoma. Recent discussion concerning the simultaneous occurrence of pulmonary tuberculosis and bronchogenic carcinoma suggests a higher coexistence of both diseases. However, the coexistence of active tuberculosis with carcinoma in the same region, as in our case, is quite rare and suggests an etiological closer relationship between both diseases.

Adenocarcinoma↗
PubMed1992

[A successful allogeneic bone marrow transplantation for acute promyelocytic leukemia with anthracycline-induced cardiomyopathy at relapse].

A 14-year-old girl with acute promyelocytic leukemia (APL) developed cardiomyopathy following chemotherapy for remission induction and subsequent consolidation consisting of cumulative doses of 644 mg/m2 of daunorubicin and 31 mg/m2 of mitoxantrone. Six months after the first complete remission, when relapse of APL was recognized an allogeneic bone marrow transplantation (BMT) from her HLA-identical brother was performed. A preconditioning regimen, consisting of cytarabine (Ara-C, 2 g/m2/day x 3 days and 4 g/m2/day x 3 days), total body irradiation (TBI, 1200 cGy) and etoposide (VP-16, 50 mg/kg) caused moderate gastrointestinal symptoms and transient hemorrhagic cystitis, but did not worsen her cardiac function. Both continuous intravenous administration of heparin to control DIC and continuous low dose dopamine infusion to prevent cardiac failure achieved their purpose. The patient is leukemia-free and has no symptoms related to cardiomyopathy at the eight month after BMT. A preconditioning regimen (Ara-C, TBI and VP-16) appeared to be suitable for BMT to a patient with anthracycline-induced cardiomyopathy.

Adolescent↗
PubMed1992

[Peripheral aneurysms of the posterior inferior cerebellar artery; analysis of 15 cases].

Peripheral aneurysms of the posterior inferior cerebellar artery (PICA) are rare. The authors report 15 cases of peripheral PICA aneurysms. Twelve of the aneurysms were discovered after their rupture and two were discovered after rupture of concomitant AVM, and one was detected incidentally. As to the location of aneurysms, more than half of the aneurysms arose at the telovelotonsillar segment. One patient had 2 aneurysms on the same peripheral PICA, which were not obvious on preoperative angiography because the ruptured one was partially thrombosed. Another rare case with aneurysm located at the internal auditory meatus is also reported. The findings of CT were characteristic, namely hemorrhage in the fourth ventricle without obvious hemorrhage in the basal cisterns, or only within the cerebellar vermian cistern. This phenomenon strongly suggested the possibility of rupture of peripheral PICA aneurysms. As to the surgical results, 10 patients (71%) of the 14 patients had a good recovery, and 1 patient (7%) with nonrupture aneurysm had a fair result due to pre-existing pontine hemorrhage. Three patients (21%) died. Rebleeding occurred in 3 patients, but cerebral vasospasm occurred in only 1 patient. Consequently, as peripheral PICA aneurysms are likely to be missed, and rebleeding is an unfavorable factor, one should try to demonstrate aneurysms with angiography, by using various methods such as subtraction or magnification.

Adolescent↗
PubMed1992

[Traumatic rupture of the diaphragm--a case of lung herniation into the abdominal cavity].

A first case of lung herniation into abdominal cavity with traumatic diaphragmatic rupture is described. A 41-year-old Japanese man with chronic obstructive pulmonary disease suffered traumatic diaphragmatic rupture. He needed to get continuous mandatory ventilation for a long time. At the time of operation, left lung herniation into the abdominal cavity was observed. When those who have chronic obstructive pulmonary disease suffered thoraco-abdominal injury, we should take care that pulmonary herniation might exist.

Abdomen↗
PubMed1992

[Endoscopic Nd-YAG laser therapy and tracheobronchial surgery].

We applied endoscopic Nd-YAG laser therapy to eight cases before the tracheobronchial surgery (six lung cancers and two metastatic tracheal tumors). The preoperative application of Nd-YAG laser is a useful choice for the release of air way stenosis, the defining the border of tumor extension and the securing endotracheal intubation for anesthesia. More cases come into the category of surgical indication when Nd-YAG laser is applied, combined with chemotherapy and/or radiation. Preoperative evaluation of the limit of tracheobronchial resection as well as the method of the reconstruction are essential, however, the precise line of the dissection should be determined by knowing the histological finding of the resected by during the operation to make sure of the operative radicality.

Adult↗
PubMed1991

Similarity and difference in the mechanisms of neonatally induced tolerance and cyclophosphamide-induced tolerance in mice.

The mechanisms of cyclophosphamide (CP)-induced tolerance were investigated by comparing with those of neonatally induced tolerance. When C3H/He Slc (C3H; H-2k, Mls-1b) mice were given i.v. either AKR/J Sea (AKR; H-2k, Mls-1a) or (AKR x C3H)F1 (AKC3F1; H-2k, Mls-1a/b) spleen cells and treated i.p. with CP 2 days later, a long-lasting skin allograft tolerance to AKR was induced in each case without any signs of graft-vs-host disease (GVHD). However, typical signs of GVHD were observed in the C3H mice neonatally tolerized with AKR spleen cells, but not in those tolerized with AKC3F1 spleen cells. The expression of TCR V beta 6, which is strongly correlated with the reactivity to Mls-1a Ag (of donor AKR origin), in the periphery was quite different between the two types of tolerant C3H mice. Namely, in the lymph nodes of the C3H mice tolerized with AKR spleen cells and CP, only CD4(+)-V beta 6+, but not CD8(+)-V beta 6+, T cells selectively disappeared, whereas both of them were abrogated in the lymph nodes of the C3H mice neonatally tolerized of AKR. By contrast, in the thymus of the two types of tolerant C3H mice, both CD4+CD8- and CD4-CD8+ single-positive thymocytes expressing TCR V beta 6 were clonally deleted, suggesting that the thymic involvement was the same in each type of tolerance. These results suggest that the preferential disappearance of the CD4(+)-V beta 6+ T cells (of host origin) and the effector T cells of GVHD (of donor origin) occurred only in the periphery of the C3H mice tolerized with AKR spleen cells plus CP and was attributable to the destruction of Ag-stimulated T cells by the CP treatment. In contrast, the intrathymic clonal deletion of immature V beta 6+ T cells was a common mechanism for both of the tolerance induction systems.

Animals↗
PubMed1991

Serological discrimination between HTLV-I and HTLV-II antibodies by ELISA using synthetic peptides as antigens.

Using the peptides from amino acids 100-130 of the HTLV-I gag protein, 175-199 of the HTLV-I env protein and the corresponding peptides of HTLV-II (amino acids 106 to 135 of the gag protein and 171 to 196 of the env protein), we tested for reactivity against antibodies by enzyme immunoassay in sera from HTLV-I and HTLV-II carriers. The peptides derived from the env proteins have high specificity for antibody binding. The peptide based on amino acids 175-199 of HTLV-I reacted with antibodies in sera from all HTLV-I carriers, and the peptide composed of amino acids 171-196 of HTLV-II reacted with antibodies in sera from all HTLV-II carriers. For the peptides derived from the gag proteins, we observed some cross-reactivity in sera from persons with anti-HTLV-I and anti-HTLV-II, due to antibody binding to the peptide corresponding to 12 amino acids from the C-terminal end of the gag protein. Separate enzyme immunoassays that used the four synthetic peptides as antigens clearly distinguished between serum with antibodies to HTLV-I or HTLV-II in various individuals and excluded false positive results using the particle agglutination assay that used a whole-virus lysate of HTLV-I as antigen.

Amino Acid Sequence↗
PubMed1991

Bafilomycin A1 inhibits the targeting of lysosomal acid hydrolases in cultured hepatocytes.

Effects of bafilomycin A1, an inhibitor of vacuolar H(+)-ATPase, on the synthesis and processing of cathepsin D and cathepsin H were investigated in primary cultured rat hepatocytes. Pulse-chase experiments showed that after being synthesized as procathepsin D and procathepsin H the precursors were converted into mature forms in the control cells as the chase time elapsed. However, in the presence of 5 x 10(-7) M of bafilomycin A1, both precursors were largely secreted into the medium and no mature forms were found within the cells. Thus bafilomycin A1 mimics lysosomotropic amines with regard to perturbation of the targeting of lysosomal acid hydrolases. In contrast, bafilomycin A1 was found not to inhibit processings of proalbumin and procomplement component 3, which are thought to occur at the acidic trans-Golgi, implying that the proteolytic event of the proproteins is not sensitive to an increase of intra-Golgi pH. The results suggest that bafilomycin A1 is useful as a pH-perturbant to study the role of acidity in living cells.

Animals↗
PubMed1991

Three-dimensional trajectories of the hippocampal rhythmic slow activity in the behaving rat.

Movement-concurrent rhythmic slow activity (RSA) was recorded by means of 3 pairs of bipolar electrodes which were arranged so that they orthogonally encompassed the dorsal hippocampus in the freely moving rat. The 3-channel data were combined by synchronously plotting them on independent voltage axes and the resultant 3-channel Lissajous' trajectory (3-CLT) was depicted in 3-dimensional microcomputer processing. A type of 3-CLT which traversed the surface of an ellipsoid with the long axis nearly perpendicular to the medial CA1 pyramidal layer, appeared most abundantly during walking. A 3-CLT depicting curves on a spherical surface was frequently produced during sitting. A linear 3-CLT of short duration was occasionally produced during rearing. These findings suggest that alteration of voltage axis specific to a behavior is possibly generated associating with the hippocampal RSA.

Animals↗
PubMed1991

Occurrence of ceramide digalactoside as the main glycosphingolipid in the marine sponge Halichondria japonica.

The main glycosphingolipid of the sponge Halichondria japonica was isolated and its structure was determined to be ceramide digalactoside, Gal alpha 1----4Gal beta 1----1Cer, using FAB/MS, IR, 1H-NMR and chemical methods such as permethylation analysis and degradation techniques. The ceramide moiety was composed mainly of 4-hydroxy-iso-octadecasphinganine and 2-hydroxy-docosanoic acid. Interestingly, the branched long-chain bases were comprised of 70% total long-chain bases and 17.5% 4-hydroxy-anteiso-nonadecasphinganine. Ceramide monohexoside, consisting of galactosyl ceramide (81%) and glucosyl ceramide (19%), was also isolated as a minor component. The composition of the ceramide moiety was nearly the same as that of ceramide digalactoside.

Animals↗
PubMed1991

HLA-DQ-restricted CD4+ T cells specific to streptococcal antigen present in low but not in high responders.

We have found that the low immune response to streptococcal cell wall Ag (SCW) was inherited as a dominant trait and was linked to HLA, as deduced from family analysis. In the present report, HLA class II alleles of healthy donors were determined by serology and DNA typing to identify the HLA alleles controlling low or high immune responses to SCW. HLA-DR2-DQA1*0102-DQB1*0602(DQw6)-Dw2 haplotype or HLA-DR2-DQA1*0103-DQB1*0601(DQw6)-DW12 haplotype was increased in frequency in the low responders and the frequency of HLA-DR4-DRw53-DQA1*0301-DQB1*0401(DQw4)-Dw15 haplotype or HLA-DR9-DRw53-DQA1*0301-DQB1*0303(DQw3)-Dw23 haplotype was increased in the high responders to SCW. Homozygotes of either DQA1*0102 or DQA1*0103 exhibited a low responsiveness to SCW and those of DQA1*0301 were high responders. The heterozygotes of DQA1*0102 or 0103 and DQA1*0301 showed a low response to SCW, thereby confirming that the HLA-linked gene controls the low response to SCW, as a dominant trait. Using mouse L cell transfectants expressing a single class II molecule as the APC, we found that DQw6(DQA1*0103 DQB1*0601) from the low responder haplotype (DR2-DQA1*0103-DQB1*0601(DQw6)-Dw12) activated SCW-specific T cell lines whereas DQw4(DQA1*0301 DQB1*0401) from the high responder haplotype (DR4-DRw53-DQA1*0301-DQB1*0401(DQw4)-Dw15) did not activate T cell lines specific to SCW. However, DR4 and DR2 presented SCW to CD4+ T cells in both the high and low responders to SCW, hence the DR molecule even from the low responder haplotype functions as an restriction molecule in the low responders. Putative mechanisms linked to the association between the existence of DQ-restricted CD4+ T cells specific to SCW, and low responsiveness to SCW are discussed.

Bacterial Proteins↗
PubMed1991

Recombinant human granulocyte colony-stimulating factor improves the compromised state of recipient mice without affecting the induction of specific tolerance in the cyclophosphamide-induced tolerance system.

The effects of recombinant human granulocyte CSF (rhG-CSF) on cyclophosphamide (CP)-induced tolerance was studied. In the recipient C57BL/10 Sn Slc (B10) mice given 1 x 10(8) B10.BR Sg Sn Slc (B10.BR) spleen cells (SC) on day -2 followed by 200 mg/kg CP on day 0, the number of leukocytes and neutrophils in the periphery declined to their minimum levels on day 4. When rhG-CSF in a dose of 200 micrograms/kg was given daily for 5 days to the B10 mice, which had been treated with B10.BR SC and CP, starting one day after the administration of CP, the leukocyte and neutrophil counts declined to the same levels as those in the B10 mice treated with B10.BR SC and CP alone on day 2. On day 4, however, the counts recovered to their normal levels. The nucleated cell count of the spleen in the B10 mice given B10.BR SC and CP followed by rhG-CSF decreased less and recovered faster than that in the B10 mice given B10.BR SC and CP. The case was found to be the same in bone marrow, and the difference did not reach statistical significance. When the recipient mice were inoculated i.p. with 4 x 10(4) Pseudomonas aeruginosa (GNB-139) on day 4, the survival of the B10 mice treated with B10.BR SC and CP was markedly improved by rhG-CSF administration. The administration of rhG-CSF did not affect either the prolongation or the specificity of skin allograft survival, as shown in an H-2 mis-matched combination of B10.BR----B10 and in an H-2 identical combination of AKR/J Sea(AKR)----C3H/HeN Crj (C3H). The tolerant state, which was demonstrated by various immune responses, such as CTL, delayed footpad reaction, and antibody, was also not affected by rhG-CSF. Furthermore, the basic mechanisms for inducing a long-lasting skin allograft tolerance in this system--namely, the specific destruction of Ag-stimulated and then proliferating mature T cells in the periphery, the establishment of mixed chimerism, and the intrathymic clonal deletion of immature T cells--were preserved even when rhG-CSF was given to C3H mice previously made tolerant of AKR.

Animals↗