Biomedical subjects

R Kobayashi

Publications and source records attributed to R Kobayashi.

At least 271 records · Page 15Linked to original sources

PubMed1994

Acute lymphoblastic leukemia and non-Hodgkin's lymphoma with mediastinal mass--a study of 23 children; different disorders or different stages?

Mediastinal tumor was found in both acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL). Most cases showed the T-cell phenotype. We query whether these two diseases are in fact different disorders or merely different stages of the same disease. Twelve ALL patients with a mediastinal mass and eleven NHL patients with a mediastinal mass under 15 years of age were studied with respect to cytogenetics, immunophenotype, genotype and clinical features. Clonal chromosome abnormalities were found in 75% (9/12) of the ALL patients and 100% (11/11) of the NHL patients. Of the 20 patients with chromosome abnormalities, 12 (60%) had translocations involving 14q11-13 and 7q35 (8 ALL, 4 NHL). t(9;17)(q34;q23) was found only in 3 patients with NHL. All showed the T-cell phenotype except two, who had none of the chromosomal abnormalities frequently detected in T cell ALL/NHL. In T-cell patients, immunophenotypical staging of ALL showed a predominance of early and common thymocyte phenotypes while that of NHL showed a predominance of common thymocyte phenotypes. All 7 of the T-cell patients examined showed rearrangements of the T-cell receptor beta chain gene. On the other hand, two non-T-cell, non-B-cell patients showed no rearrangement. There were no apparent clinical differences between ALL and NHL patients in age (median 8.6 vs 8.9 years), sex ratio (F/M 9/3 vs 7/4) or in the rate of complete remission (90% vs 100%). Our study demonstrated no relevant clinical, prognostic, or immunophenotypic differences between ALL and NHL with mediastinal mass.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1994

Lung cancer containing growth hormone-releasing hormone associated with hypertrophic osteoarthropathy. Case report.

In a 49-year-old man, large-cell carcinoma of the lung was accompanied by raised serum levels of growth hormone (GH) and growth hormone-releasing hormone (GHRH) and hypertrophic osteoarthropathy. Immunohistochemically the tumour contained GHRH but not GH. The osteoarthropathy disappeared after resection of the primary tumour and did not reappear after its recurrence. The high serum GH level presumably was due to ectopic GHRH production in the tumour. The hypertrophic osteoarthropathy was not clearly attributable to these hormones.

Carcinoma, Non-Small-Cell Lung↗

PubMed1994

[Cyst puncture and injection of contrast medium for diagnosis and treatment of pericardial cyst].

We present two cases of pericardial cyst diagnosed by cyst puncture and the injection of contrast medium. The first patient was a 48-year-old man. He was admitted for the evaluation of an abnormal chest X-ray which demonstrated a mass lesion inseparable from the right heart border. CT scan confirmed the mass in the anterior cardiophrenic angle. The mass was quite homogeneous, with an attenuation value of -0.3 HU. Under CT guidance a 21-G needle was inserted into the cyst and 3 ml of clear fluid was obtained, and then contrast medium was injected. A thin smooth walled cyst was outlined by the CT scan. A presumptive diagnosis of pericardial cyst was made. Surgery was performed and the diagnosis was confirmed. The second patient was a 24-year-old woman. An abnormal shadow was noted at annual check up. CT scan confirmed the mass in the anterior cardiophrenic angle. The mass was quite homogeneous, with an attenuation value of +10.4 HY. We made the diagnosis of pericardial cyst by cyst puncture and injection of contrast medium. The CT scan after three months showed no recurrence of the pericardial cyst. We consider that pericardial cyst can be diagnosed clearly by cyst puncture and the injection of contrast medium, and only percutaneous aspiration of the cyst fluid may be sufficient for the treatment.

Adult↗

PubMed1994

Protein kinase inhibitors.

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1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗

PubMed1994

[Clinicopathological examination of the relation between Clara cells and smoking].

The relations between the number and cell area of Clara cells and smoking were examined in the lung tissue of 71 subjects by immunohistochemistry, using an anti-protein 1 antibody, which is a marker of Clara cells. The smokers showed significantly lower numbers of Clara cells than the non-smokers (p < 0.05). Although the mean non-smoking time in the ex-smokers was as long as 9 years, the ex-smokers showed a somewhat lower number of Clara cells than the non-smokers. The cell area of Clara cells was the same for smokers and non-smokers. We found that smoking reduces the number of Clara cells.

Adult↗

PubMed1994

[Postoperative pulmonary complications in patients undergoing thoracic surgery with special reference to preoperative respiratory muscle strength and nutrition].

Postoperative pulmonary complications in patients undergoing thoracic surgery were examined along with their preoperative respiratory muscle strength and nutrition. Respiratory muscle strength was assessed by maximum inspiratory (MIP) and expiratory (MEP) pressures. Nutrition was assessed by serum levels of albumin and total cholesterol. The examined cases include 51 cases of lung tumors, 8 cases of mediastinal tumors, 9 cases of empyema, 3 cases of esophageal cancer, 2 cases of chest wall tumors, and 2 cases of giant bulla. Preoperative respiratory muscle training increased both MIP and MEP significantly (p < 0.01). Thirteen patients who had postoperative pulmonary complications had significantly lower values (p < 0.01), and did not show significant increases in either MIP or MEP even after training. The cases which experienced complications also showed significantly lower preoperative serum levels of albumin and total cholesterol (p < 0.01). Therefore, patients with respiratory muscle weakness and poor nutrition have a higher risk of postoperative pulmonary complications.

Adult↗

PubMed1994

[Three cases of hematologic malignancies with jumping translocation].

We treated three cases of hematologic malignancies (Burkitt's lymphoma, ALL (L3), AML (M0)) with jumping translocations. Tumor formation was easily occurred in all three cases. The location of the jumping translocation was 1q21 in all three cases. Hematologic malignancies with jumping translocation tend to be B-cell lineage and have poor prognosis. The significance of jumping translocation is unknown yet, but it seems that jumping translocation is related to the tumor progression, rather than tumorigenesis. So that the intensive therapy including bone marrow transplantation must be considered.

Adolescent↗

PubMed1993

Yeast origin recognition complex functions in transcription silencing and DNA replication.

The genes encoding two of the subunits of the Saccharomyces cerevisiae origin recognition complex (ORC) have been isolated. Characterization of a temperature-sensitive mutation in the gene encoding the 72-kD subunit of ORC (ORC2) indicates that this protein complex functions early in the DNA replication process. Moreover, ORC derived from orc2ts cells is defective for DNA binding. Others have shown a defect in orc2ts cells in transcriptional silencing at the silent mating-type loci. Consistent with this finding, ORC specifically binds to each of the four mating-type silencers identified in yeast. These findings support the hypothesis that ORC acts as an initiator protein at yeast origins of DNA replication and suggest that ORC also functions in the determination of transcriptional domains.

Amino Acid Sequence↗

PubMed1993

p21 is a universal inhibitor of cyclin kinases.

Deregulation of cell proliferation is a hallmark of neoplastic transformation. Alteration in growth control pathways must translate into changes in the cell-cycle regulatory machinery, but the mechanism by which this occurs is largely unknown. Compared with normal human fibroblasts, cells transformed with a variety of viral oncoproteins show striking changes in the subunit composition of the cyclin-dependent kinases (CDKs). In normal cells, CDKs exist predominantly in multiple quaternary complexes, each containing a CDK, cyclin, proliferating cell nuclear antigen and the p21 protein. However, in many transformed cells, proliferating cell nuclear antigen and p21 are lost from these multiprotein enzymes. Here we have investigated the significance of this phenomenon by molecular cloning of p21 and in vitro reconstitution of the quaternary cell-cycle kinase complexes. We find that p21 inhibits the activity of each member of the cyclin/CDK family. Furthermore, overexpression of p21 inhibits the proliferation of mammalian cells. Our results indicate that p21 may be a universal inhibitor of cyclin kinases.

Amino Acid Sequence↗

PubMed1993

Autoantigen inhibits apoptosis of a human B cell leukemia that produces pathogenic rheumatoid factor.

We studied a variant CD5- B cell chronic lymphocytic leukemia (CLL) cell population that produces pathologic IgM kappa rheumatoid factor autoantibodies. In contrast to common CD5+ B cell CLL, this variant leukemia cell population displays intraclonal diversity in its expressed Ig V genes, similar to that noted for follicular B cell non-Hodgkin's lymphomas. Also, in contrast to common B cell CLL, these leukemia cells rapidly undergo cell death hours after being placed in tissue culture. We find that addition of Ag (aggregated human IgG) enhances significantly the survival of these cells in vitro. Leukemia cell survival also could be enhanced by exogenous IFN-gamma or anti-CD40 presented on Fc gamma RII (CDw32)-expressing L cells, but not by exogenous IL-4, IL-6, or monomeric human IgG. We find that Ag acts directly on the leukemia B cells to inhibit apoptosis. This effect could be mimicked by cross-linking the leukemia cells' surface IgM receptors with immobilized murine mAb specific for human Ig mu-chains, but not by immobilized mAb of irrelevant specificity. In contrast to most follicular NHL, this leukemia B cell population does not have evidence of bcl-2 gene rearrangement. Also, in contrast to non-Hodgkin's lymphomas and most B cell CLL, these cells do not express detectable amounts of bcl-2. Finally, although capable of inhibiting apoptosis, surface Ig receptor cross-linking does not induce expression of bcl-2 in these variant leukemia cells. We hypothesize that the lack of bcl-2 expression may render these leukemia cells particularly dependent upon the survival signal(s) derived from surface Ig receptor cross-linking. This state may represent an early stage in leukemia/lymphomagenesis, possibly accounting for the intraclonal diversity observed in the Ig V genes expressed by certain CD5- B cell leukemias and lymphomas.

Antigens, CD↗

PubMed1993

Complex synthetic chemical libraries indexed with molecular tags.

Combinatorial methods of chemical synthesis allow the creation of molecular libraries having immense diversity. The utility of such libraries is dependent upon identifying the structures of the molecules so prepared. We describe the construction of a peptide combinatorial library, having 117,649 different members, synthesized on beads and indexed with inert chemical tags. These tags are used as a binary code to record the reaction history of each bead. The code can be read directly from a single bead by electron capture capillary gas chromatography. We demonstrate the correct selection of members of the library on the basis of binding to a monoclonal antibody.

Amino Acid Sequence↗

PubMed1993

cDNAs encoding the large subunit of human replication factor C.

Replication factor C (RFC) is a multisubunit, DNA polymerase accessory protein required for the coordinated synthesis of both DNA strands during simian virus 40 DNA replication in vitro. Previous studies have shown that RFC is a DNA-dependent ATPase that binds in a structure-specific manner to the 3' end of a primer hybridized to a template DNA, an activity thought intrinsic to the 140-kDa component of this multisubunit complex. Here, the isolation and analysis of cDNAs encoding this subunit is described. Analysis of the full-length coding sequence revealed an open reading frame of 3.4 kb, encoding an 1148-amino acid protein with a predicted molecular mass of 130 kDa. A putative ATP-binding motif was observed that is similar to a motif in several of the smaller subunits of RFC and in functionally homologous replication factors of bacterial and viral origin. A "DEAD" box is also conserved among these proteins. The predicted protein shows significant identity with a DNA-binding protein of murine origin (B. Luckow, P. Lichter, and G. Schütz, personal communication). Regions of similarity were also seen between the amino acid sequences of the 140-kDa subunit of RFC, poly(ADP-ribose) polymerase, and bacterial DNA ligases--possibly representing a conserved structural feature of these proteins that bind similar DNA substrates.

Amino Acid Sequence↗

PubMed1993

Purification and cDNA cloning of HeLa cell p54nrb, a nuclear protein with two RNA recognition motifs and extensive homology to human splicing factor PSF and Drosophila NONA/BJ6.

While searching for a human homolog of the S.cerevisiae splicing factor PRP18, we found a polypeptide that reacted strongly with antibodies against PRP18. We purified this polypeptide from HeLa cells using a Western blot assay, and named it p54nrb (for nuclear RNA-binding protein, 54 kDa). cDNAs encoding p54nrb were cloned with probes derived from partial sequence of the purified protein. These cDNAs have identical coding sequences but differ as a result of alternative splicing in the 5' untranslated region. The cDNAs encode a 471 aa polypeptide that contains two RNA recognition motifs (RRMs). Human p54nrb has no homology to yeast PRP18, except for a common epitope, but is instead 71% identical to human splicing factor PSF within a 320 aa region that includes both RRMs. In addition, both p54nrb and PSF are rich in Pro and Gln residues outside the main homology region. The Drosophila puff-specific protein BJ6, one of three products encoded by the alternatively spliced no-on-transient A gene (nonA), which is required for normal vision and courtship song, is 42% identical to p54nrb in the same 320 aa region. The striking homology between p54nrb, PSF, and NONA/BJ6 defines a novel phylogenetically conserved protein segment, termed DBHS domain (for Drosophila behavior, human splicing), which may be involved in regulating diverse pathways at the level of pre-mRNA splicing.

Amino Acid Sequence↗

PubMed1993

Phosphorylation of annexin XI (CAP-50) in SR-3Y1 cells.

Annexin XI (CAP-50) is a probable target protein of calcyclin. Being different from other annexins, annexin XI localizes mainly in nuclei of cultured fibroblasts. In rat embryonic fibroblasts transformed by Rous sarcoma virus oncogene, SR-3Y1 cells, phosphorylation of annexin XI was increased on both serine and threonine residues (Ser < Thr), compared with findings in control 3Y1 cells. The amount of phosphorylated annexin XI was approximately 8.5% of the total cellular annexin XI and the phosphorylated annexin XI migrated slightly slower on SDS-polyacrylamide gel electrophoresis than did the non-phosphorylated form of annexin XI. Phosphorylated annexin XI was recovered in the cytoplasmic fraction and did not bind to phosphatidylserine vesicle in the presence of high Ca2+ (over 1 mM). Annexin XI was phosphorylated by mitogen-activated protein (MAP) kinase, which was reported to be activated in v-src-transformed fibroblast (Gupta, S. K., Gallego, C. Johnson, G.L. and Heasley, L.E. (1992) J. Biol. Chem. 267, 7987-7990), on both serine and threonine residues (Ser >> Thr) in vitro. Comparative phosphopeptide mappings analyzed by reverse-phase high performance liquid chromatography suggested that the sites phosphorylated in situ in SR-3Y1 cells are distinct from the sites by MAP kinase. Annexin XI phosphorylated by MAP kinase still possessed the ability to bind to phosphatidylserine vesicle. These results suggest that annexin XI is a substrate for some Ser/Thr kinase(s) which is activated in v-src-transformed cells and that the phosphorylation may regulate the function of annexin XI in living cells.

Animals↗

PubMed1993

Cone dysfunction and supernormal scotopic electroretinogram with a high-intensity stimulus. A report of three cases.

An unusual form of scotopic electroretinogram with a bright white stimulus, which consisted of a rectangular a-wave of normal amplitude and a b-wave of supernormal amplitude, was recorded in three patients with cone dysfunction. In addition to poor visual acuity, abnormal color vision and reduced amplitude of the photopic electroretinogram, these patients showed a 2-log unit elevation of the dark-adaptation threshold. Funduscopic examination and fluorescein angiography revealed fine granular pigment disturbances at the macula. The relationship between the response of the dark-adapted electroretinogram versus stimulus intensity was unique to these patients. The b-wave thresholds were elevated by 1 log unit. The b-waves were reduced in amplitude and markedly delayed in implicit time to dim stimuli, but supernormal in amplitude and normal in implicit time to bright stimuli.

Adolescent↗

PubMed1993

Indications for an expandable metallic stent for tracheobronchial stenosis.

An expandable metallic stent was used in 9 patients with tracheobronchial stenosis. Of the 8 patients with malignant stenosis, 6 had extrinsic compression and 2 had intraluminal tumor invasion. The 1 patient with nonmalignant stenosis had postreconstruction bronchomalacia and granulation tissue affecting different parts of the tracheobronchial tree. The expandable metallic stent successfully dilated tracheobronchial stenosis due to extrinsic tumor compression and malacia. However, it was not effective for stenosis due to intraluminal tumor invasion or granulation tissue because of the growth of tumor or granulation tissue between the wires of the stent. However, an expandable metallic stent covered with Dacron mesh was effective in 1 patient with intraluminal tumor invasion because tumor growth was blocked by the mesh. We conclude that an expandable metallic stent is effective for tracheobronchial stenosis due to extrinsic tumor compression, but not for stenosis due to intraluminal tumor invasion or granulation tissue.

Adult↗

PubMed1993

Jumping translocations of 1q in Burkitt lymphoma and acute nonlymphocytic leukemia.

"Jumping translocations" have been observed mostly in cultured cells. Reports of such translocations in hematologic malignancies are few, and the associated clinical picture is unclear. We report three cases of hematologic malignancies with various unbalanced translocations (so-called jumping translocation) involving trisomy of the long arm of chromosome 1. The first case was a 13-year-old boy with Burkitt lymphoma who showed a very aggressive clinical course. The second case was a 10-month-old girl with acute nonlymphocytic leukemia [ANNL, French-American-British (FAB) classification M0] who had high risk factors, including hyperleukocytosis with a peripheral white blood cell (WBC) count of 300,000/microliters, and who died 7 months after diagnosis. The third case was a 6-year-old boy with Burkitt-like leukemia whose first remission lasted only 1 month. Only 10 cases with jumping translocations, including two cases with Burkitt-like leukemia/lymphoma, have been reported previously. This rare phenomenon may occur with increased frequency in Burkitt-like leukemia/lymphoma and may be an adverse prognostic factor.

Adolescent↗

PubMed1993

Characteristics of those who refuse to attend school in Fukuoka City: an analysis based on teachers' reports.

In 1988, we investigated the characteristics of children who refused to attend elementary and junior high schools in Fukuoka City, mainly from the viewpoint of their present status. The main results were as follows: Prevalence of school refusers in elementary schools (0.13%) was much higher in Fukuoka City than in all Japan, but almost similar in junior high schools (0.47%). About one-third of the school refusers didn't mind their absence so much, and more school refusers in junior high schools could not understand the significance of school attendance. These results suggest that school refusers, who may have a borderline personality organization, are likely to prevail.

Absenteeism↗