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S Takai

Publications and source records attributed to S Takai.

At least 217 records · Page 12Linked to original sources
PubMed1994

Human high-affinity Fc gamma RI (CD64) gene mapped to chromosome 1q21.2-q21.3 by fluorescence in situ hybridization.

The human Fc gamma RI gene encodes for a high-affinity Fc gamma receptor that plays pivotal roles in the immune response. We have used fluorescence in situ hybridization analysis to localize the Fc gamma RI gene to human chromosome 1. The human Fc gamma RI (CD64) gene has been assigned to human chromosome 1q21.2-q21.3 using R-banded human (pro)metaphase chromosomes.

Chromosome Mapping↗
PubMed1994

Refined mapping of eight cosmid markers on human chromosome 22.

Eight cosmid clones were regionally assigned to small subregions of chromosome 22 by hybridization with a total of 22 somatic cell hybrids. One cosmid was localized to the proximal part of 22q which contained the region commonly deleted in the DiGeorge syndrome. Seven cosmids showing restriction fragment length polymorphisms were localized to the telomeric region distal to the MB locus, which was reported to be frequently deleted in sporadic meningioma. These cosmids, when finely mapped and ordered, are considered useful for the identification of genetic alterations on this chromosome arm.

Chromosome Mapping↗
PubMed1994

Effect of growth temperature on maintenance of virulent Rhodococcus equi.

Repeated passage of virulent Rhodococcus equi ATCC 33701 and L1 at 38 degrees C resulted in attenuation of the strains as a result of curing the virulence plasmid; at 30 degrees C, repeated passage had no such effect. At a temperature of 38 degrees C the plasmid-bearing cells replicated more slowly than their plasmid-cured derivatives and so were gradually replaced by cells lacking plasmids. In contrast, at a temperature of 30 degrees C the growth rate of either strain was not affected by the presence or absence of the plasmid. No plasmid-cured derivative was recovered from mouse organs at 48 h after inoculation of a mixture of equal numbers of bacteria with and without plasmids. It is concluded that under nonselective conditions growth temperature is an important factor in maintaining the virulence of R. equi.

Actinomycetales Infections↗
PubMed1994

Localization and quantitation of active renin in monkey kidney by radioinhibitor binding and in vitro autoradiography.

We developed an in vitro autoradiographic method to localize and quantify active renin in primate tissues. Active renin in monkey kidney sections was labeled with the primate specific renin inhibitor, 3H-CGP29287, and quantitated with autoradiography and computerized densitometry. Microscopic emulsion autoradiography was carried out to clarify the detailed localization of the binding. Non-specific binding to aspartyl proteases other than renin was blocked using 1 mumol/L of N-acetyl-pepstatin. To assess the usefulness of this procedure, binding of 3H-CGP29287 was examined both by film and emulsion autoradiography in the kidneys of monkeys (Macaca fuscata) that were given chronically either an angiotensin converting enzyme inhibitor (trandolapril), an angiotensin II receptor antagonist (E4177), or vehicle. 3H-CGP29287 was found to bind very selectively to the juxtaglomerular apparatus (JGA) under control conditions. In monkeys treated with trandolapril or E4177, 3H-CGP29287 binding was increased in proportion to the increase in renal renin concentration determined enzymatically; in these kidneys, emulsion autoradiography revealed radioinhibitor binding extending far from the JGA. The potency of a series of unlabeled renin inhibitor in competing for 3H-CGP29287 binding in the autoradiographic system closely paralleled their potencies, as determined in inhibiting renin by an enzymatic assay. This technique permits specific labeling of the catalytic site of renin in the monkey kidney sections.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1994

Two-headed, two-necked conjoined twin calf with Arnold-Chiari malformation in a Japanese shorthorn calf.

A dicephalic Arnold-Chiari malformation (ACM) case revealed asymmetrical cranial bone abnormalities: the right cranium had the typical findings associated with bovine monocephalic ACM cases, whereas the left cranium had malformation that has not yet been described in previous bovine ACM cases. The only common finding in each cranium was a relative smallness of the cranium as the encasement of the brain.

Abnormalities, Severe Teratoid↗
PubMed1994

Virulence of Rhodococcus equi isolates from patients with and without AIDS.

Rhodococcus equi is an emerging opportunistic pathogen of human immunodeficiency virus-infected patients. Thirty-nine isolates of R. equi from immunocompromised patients with and without AIDS were analyzed for the presence of virulence plasmid DNA, expression of 15- to 17-kDa antigens, and their pathogenicities in mice. Of the human isolates, eight contained an 85-kb virulence plasmid, expressed 15- to 17-kDa antigens, and were virulent in mice. Nineteen isolates carried cryptic plasmids of various sizes, and the remaining 12 isolates did not contain any plasmids. These 31 isolates did not express virulence-associated antigens and were not virulent in mice. The results suggested that opportunistic infections in immunocompromised patients could be caused by both virulent and avirulent R. equi strains and that the pathogenesis of R. equi infection in immunocompromised patients appears to be different from that which occurs in foals.

AIDS-Related Opportunistic Infections↗
PubMed1994

Evaluation of a monoclonal antibody-based colony blot test for rapid identification of virulent Rhodococcus equi.

We recently generated a monoclonal antibody immunoglobulin G1 (MAb 10G5), which can recognize 15- to 17-kDa antigens, virulence-associated antigens of Rhodococcus equi, and developed a colony blot enzyme-linked immunosorbent assay with MAb 10G5 for the rapid identification of virulent R. equi. In this epidemiologic study, we evaluated the results of the colony blot test in the identification of virulent isolates of R. equi from feces of horses and soil and compared them with those from a conventional procedure (plasmid profiles of isolates by agarose gel electrophoresis). Environmental isolates (778 isolates from feces of foals, 170 isolates from feces of dams, and 1,267 isolates from soil on horse-breeding farms in Hokkaido) were tested by the colony immunoblot test, and 238 of the 778 isolates, 6 of the 170 isolates, and 85 of the 1,267 isolates showed positive signals. Positive isolates were then analyzed for the presence of virulence plasmid DNA, and 235 (98.7%) of the 238 isolates from foals, 6 (100%) of the 6 isolates from dams, and 75 (88.2%) of the 85 isolates from soil showed the presence of virulence plasmids. On the other hand, 50 isolates from each source, which were randomly selected from the isolates that showed negative signals by colony immunoblot, did not contain virulence plasmids. These results demonstrated that the colony blot test that uses a monoclonal antibody specific for virulence-associated antigens is a rapid and reliable test for the identification of virulent R. equi.

Actinomycetales Infections↗
PubMed1994

[Therapeutic strategy for anaplastic carcinoma and malignant lymphoma of the thyroid].

Therapeutic strategies for anaplastic carcinoma and malignant lymphoma of the thyroid are reviewed. Because of the rarity of both diseases among thyroid malignancies, the generally accepted treatment policy has not been established, although the importance of radiation therapy and chemotherapy has been well recognized for the treatment of both diseases. Hyperfractionated radiation therapy combined with suitable systemic chemotherapy will counter anaplastic thyroid carcinoma and prolong survival. Most patients with thyroid malignant lymphoma have better prognoses than anaplastic carcinoma patients. But delayed diagnosis and inadequate treatment still results in a poor prognosis, in spite of the more treatable characteristics of thyroid malignant lymphoma than anaplastic thyroid carcinoma. At present, early detection of the tumor and selection of a suitable therapy is necessary for the improvement of prognosis, and further clinical studies are required to establish effective regimens for multidisciplinary treatment.

Carcinoma↗
PubMed1993

Determination of the in situ loads on the human anterior cruciate ligament.

A noncontact, kinematic method was used to determine the lengths and in situ loads borne by portions of the human anterior cruciate ligament (ACL) by the combination of kinematic data from the intact knee and load-length curves of the isolated ACL. Specimens from knees of cadavers of young people were tested in passive flexion and extension as well as with 100 N of anterior tibial drawer at 0, 30, 45, and 90 degrees of flexion. The results showed that the in situ load on the whole ACL (as much as 129 N) can exceed the magnitude of the applied anterior tibial drawer. The load distribution within the ligament changes with flexion of the knee. The anterior and posterior portions share the anterior drawer force equally toward full extension. However, at flexion > 45 degrees, the anterior portion supports 90-95% of the load. This information is important for the determination of the function of the entire ACL and of its subportions in response to external loading of the intact knee. In particular, the preferential loading found for one of the portions of the ACL demonstrates that successful operative reconstruction of this ligament may not be achieved simply by reproduction of its gross anatomy; consideration of the role of the ligament in the overall kinematics of the knee is necessary.

Adult↗
PubMed1993

Increased IgE level as a marker of host-versus-graft disease: inhibition of this HVGD with a monoclonal antibody to IL-4.

BALB/c mice injected at birth with (BALB/c x C57BL/6)F1 hybrid spleen cells developed host versus graft disease (HVGD) with immunological features, such as various autoantibodies, immune complex nephritis, hepatosplenomegaly, and malignant lymphomas. In addition we found that the increased IgE levels correlated strongly with the histological grades or stages of the liver disease. In the sera of mice with HVGD and liver alterations, anti-smooth muscle antibodies (ASMA) and anti-nuclear antibodies (ANA) were detected. The subclass of ASMA was IgG1, whereas the subclasses of ANA were IgG1, IgG2a, and IgG2b. When the recipient BALB/c mice were injected at birth and at Day 3 in addition also with monoclonal anti-IL-4 antibody 11B11, the increase of IgE and IgG1 was markedly reduced and the liver disease was drastically prevented. These observations suggest that IL-4 plays an important role in the initiation of the immunoregulatory function or pathogenesis of the allogeneic effects and that the monoclonal anti-IL-4 antibody 11B11 prevents the immunodysfunctions and the autoimmune hepatopathy in mice with HVGD. The increased IgE level in the serum is a good marker of HVGD.

Animals↗
PubMed1993

Restriction map of a virulence-associated plasmid of Rhodococcus equi.

The restriction cleavage map of a virulence-associated plasmid pREAT701 of Rhodococcus equi was constructed with EcoRI and HindIII by means of cloning the restriction fragments, cross Southern hybridization with each fragment, and hybridization with probes generated by modified inverse PCR. The genetic region responsible for expression of virulence-associated 15- to 17-kilodalton antigens was determined.

Blotting, Southern↗
PubMed1993

Construction of radiation-reduced hybrids and their use in mapping of microclones from chromosome 10p11.2-q11.2.

Radiation-reduced hybrids for mapping of DNA markers in the pericentromeric region of chromosome 10 were developed. A Chinese hamster/human somatic cell hybrid (762-8A) carrying chromosomes 10 and Y as the only human material were exposed to 40,000 rads of irradiation and then rescued by fusion with non-irradiated recipient Chinese hamster cells (GM459). Southern hybridization analyses revealed that 10 of 128 HAT-resistant clones contained human chromosomal fragments corresponding to at least one marker locus between FNRB (10p-11.2) and RBP3 (10q11.2). These hybrids were then used to map micro-dissection clones previously isolated and roughly mapped to this chromosomal region by fluorescence in situ hybridization (FISH). Two of the six microclones studied could be mapped to the proximity of the D10-S102 locus. These radiation hybrids are useful for the construction of refined genetic maps of the pericentromeric region of chromosome 10.

Animals↗
PubMed1993

Purification and characterization of the 26S proteasome complex catalyzing ATP-dependent breakdown of ubiquitin-ligated proteins from rat liver.

An ATP/ubiquitin-dependent proteasome complex with an apparent sedimentation coefficient of 26S was purified from rat liver to near homogeneity by an improved method based on procedures reported previously. Two electrophoretically distinct forms of the 26S complex, named 26S alpha and 26S beta, with very similar subunit compositions were found not only in purified preparations but also in crude extracts, indicating that the 26S proteasome is present as two isoforms. The 26S proteasome was shown to degrade multi-ubiquitinated, but not unmodified, lysozymes in an ATP-dependent fashion, to have ATPase activity supplying energy for proteolysis, and to contain isopeptidase activity to generate free ubiquitin Mg2+/ATP-dependently. The 26S proteasome also catalyzed the ATP-independent hydrolyses of three types of fluorogenic peptides with basic, neutral, and acidic amino acids at their cleavage sites, respectively. These peptides are also good substrates for the 20S proteasome, but their degradation by the free 20S proteasome and by its assembled form in the 26S complex differ markedly, suggesting a functional difference between the two forms of proteasomes. Electrophoretic and immunochemical analyses showed that the large 26S complex was composed grossly of two different structures: a core 20S proteasome with multicatalytic proteinase functions and an associated part possibly with a regulatory role. These two structures both consisted of multiple polypeptides with molecular masses of 21-31 and 35-110 kDa, respectively. The subunit multiplicity of the rat 26S proteasome closely resembled that of the human counterpart, showing only minor species-specific differences in certain components. The assembly of this multi-component complex was found not to involve a sulfhydryl bond. Electrophoretic peptide mapping with lysyl-endopeptidase indicated the non-identity of the multiple subunits of the 26S proteasome. From these structural and functional characteristics, the 26S proteasome, which is widely distributed in mammals, is suggested to be a new type of multi-molecular complex catalyzing the soluble energy- and ubiquitin-dependent proteolytic pathway.

Adenosine Triphosphate↗
PubMed1993

Deletion mapping of chromosome 1p and 22q in pheochromocytoma.

To identify the localization of tumor suppressor genes, 22 pheochromocytomas (9 hereditary and 13 sporadic) were examined for loss of heterozygosity (LOH) on the short arm of chromosome 1 and on the long arm of chromosome 22 by using 11 polymorphic DNA markers on each chromosome arm. LOH on 1p was observed in 12 of 22 informative cases (55%) and on 22q in 8 of 20 informative cases (40%). There was no significant difference in the frequency of LOH on 1p or 22q between hereditary and sporadic cases. We could localize the commonly deleted regions as distal to D1S73 and proximal to D1S63 on 1p and distal to D22S24 and proximal to D22S1 on 22q. In addition, the relationship between LOH on 1p and 22q was studied in 20 pheochromocytomas which were informative for probes on both chromosome arms. Of eight tumors that showed LOH on 22q, allelic loss on 1p was also detected in seven. Thus, LOH on 22q was correlated significantly with LOH on 1p (P = 0.0249; Fisher's exact test). These results suggest that inactivation of multiple tumor suppressor genes may be required for development and progression of hereditary and non-hereditary pheochromocytoma.

Adrenal Gland Neoplasms↗
PubMed1993

Dicephalus, Arnold-Chiari malformation and spina bifida in a Japanese black calf.

A case of dicephalus, Arnold-Chiari malformation (ACM) and spina bifida was reported in a Japanese Black calf. Both brains and crania showed the same abnormalities as those of the monocephalic cases with ACM and were mirror-images of each other. The common findings were elongation of the brain, caudal displacement and hypoplasia of the cerebellum, dorso-ventral compression of the skull, platybasia, and enlargement of the foramen magnum. The craniolacunia was also found in our case.

Abnormalities, Severe Teratoid↗
PubMed1993

Monoclonal antibody specific to virulence-associated 15- to 17-kilodalton antigens of Rhodococcus equi.

Virulent Rhodococcus equi produces 15- to 17-kDa surface protein antigens. These antigens are used as markers to identify virulent R. equi isolates from foals and their environment by Western blot (immunoblot) analysis with naturally infected foal serum. In the present study, a monoclonal antibody (MAb; 10G5) was generated against the 15- to 17-kDa antigens excised from sodium dodecyl sulfate-polyacrylamide gels to develop sensitive and specific immunoblot assays for the identification of virulent R. equi. MAb 10G5 strongly reacted with R. equi ATCC 33701 and L1, which expressed 15- to 17-kDa antigens by Western blot, colony blot, and dot immunobinding assays, but it did not react with strains ATCC 33701P- and L1P-, which lacked the antigens. For identification of virulent R. equi, clinical and environmental isolates were tested by these assays with the MAb, and all virulent strains were successfully identified; these strains possessed virulence plasmids. These results suggest that the MAb is a useful reagent for the identification of virulent R. equi.

Animals↗