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T Kawakami

Publications and source records attributed to T Kawakami.

At least 253 records · Page 14Linked to original sources
PubMed1995

Early detection of prostate cancer. Results of a prostate specific antigen-based detection program in Japan.

BACKGROUND: Prostate cancer increasingly is becoming a medical problem in Japan. To maximize the chance for cure, extensive effort is being made to detect prostate cancer while confined to the gland. METHODS: Determination was made of serum prostate specific antigen (PSA) in the early detection of prostate cancer in an Asian male population aged 55 years or older. Recommendation for biopsy was based solely on this parameter when its value exceeded 2.0 ng/ml in IMx immunoenzymetric assay. RESULTS: Of 1189 men, 150 (12.6%) had elevated values. The proportion of males with serum PSA greater than 4.0 ng/ml was only 3.4%. Of the 99 males who underwent ultrasound-guided biopsies, 16 cancers were detected, a cancer detection rate of 1.3%. Most of these (81.3%) were clinically localized cancers. Seven patients with cancer had serum PSA levels below 4.0 ng/ml including 5 less than 3.0 ng/ml. These tumors would have been overlooked if the conventional cutoff levels of 4.0 ng/ml had been applied. Radical prostatectomy was conducted on 13 patients. All had histologic features of clinically significant cancer and 69.2% were pathologically confined within the gland. CONCLUSIONS: Elderly Asian males appear to have lower serum PSA than their Western counterparts. The optimal cutoff of serum PSA for early detection should be examined further in Asian male populations. Differences in the incidence of prostate cancer between ethnic groups may have been overestimated in previous studies owing in part to unawareness by the physician and general public. Though the frequent use of more sophisticated diagnostic modalities will likely disclose greater numbers of prostate cancers in Japan, whether early detection reduces mortality by minimizing risk of death from cancer remains a point to be determined.

Aged↗
PubMed1995

Molecular cloning of LSIRF, a lymphoid-specific member of the interferon regulatory factor family that binds the interferon-stimulated response element (ISRE).

Interferon regulatory factor (IRF) genes encode a family of DNA-binding proteins that are involved in the transcriptional regulation of type-I interferon and/or interferon-inducible genes. We report here the characterization of LSIRF, a new member of the IRF gene family cloned from mouse spleen by the polymerase chain reaction using degenerate primers. LSIRF was found to encode a 51 kDa protein that shares a high degree of amino acid sequence homology in the DNA-binding domain with other IRF family members. LSIRF expression was detectable only in lymphoid cells. In contrast to other IRF genes, LSIRF expression was not induced by interferons, but rather by antigen-receptor mediated stimuli such as plant lectins, CD3 or IgM crosslinking. In in vitro DNA binding studies, LSIRF was able to bind to the interferon-stimulated response element (ISRE) of the MHC class I promoter. The expression pattern and DNA binding activities suggest that LSIRF plays a role in ISRE-targeted signal transduction mechanisms specific to lymphoid cells.

Amino Acid Sequence↗
PubMed1995

Effects of acetylcholine and adrenaline on axoplasmic transport at different regions of mouse superior cervical ganglion cells in culture.

Adrenaline and acetylcholine (ACh) were applied locally at three different positions in cultured superior cervical ganglion cells, i.e., cell body, neurite, and growth cone and the effects on the axoplasmic transport were measured with a video-enhanced microscope. Local ACh application to the cell body, neurite, and growth cone caused the same decreasing effect, but the effects of local adrenaline application were different from each other. Local adrenaline application to the cell body and growth cone caused an increase of axoplasmic transport, but local application at the neurite caused no effect. These data may indicate that there was a lack of beta 2 adrenergic receptors in the neurite. Desensitization of axoplasmic transport was also examined in the SCG neurons. Repetitive adrenaline application to the cell body caused desensitization to the stimulus of adrenaline application.

Acetylcholine↗
PubMed1995

Purification of a major tyrosine kinase from RBL-2H3 cells phosphorylating Fc epsilon RI gamma-cytoplasmic domain and identification as the Btk tyrosine kinase.

Immunoglobulin E high affinity receptor-mediated signal transduction in mast cells results in a number of protein tyrosine kinases being activated as very early events in the process leading to degranulation. Some of these, such as the src kinases and the syk kinase, are known to be involved in this receptor-associated activation. In this paper we describe the search for other activation-associated tyrosine kinases by the ability to phosphorylate a cytoplasmic domain peptide of the Fc epsilon RI gamma-subunit. In utilizing a purification step previously used to isolate the 72 kDa syk kinase, we detected another kinase of molecular weight 79 kDa which we designated cd gamma kinase. The kinase was purified to near homogeneity by Heparin-agarose, Mono Q, and CM Sepharose chromatographies. The yield of enzyme was approx. 200 micrograms/10(9) cells. We characterized this kinase by its ability to phosphorylate both the cd gamma peptide (Km = 0.2 mM) and the cytoplasmic fragment of the Band III protein. The cd gamma kinase was distinguished from syk by inability to be precipitated by anti-syk antiserum and by partial peptide mapping. Cd gamma kinase was also distinguished from syk by cd gamma peptide and Band III substrate specificity. We identified the cd gamma kinase by Western blotting and by partial phosphopeptide mapping as Btk, the B-cell tyrosine kinase found to be defective in X-linked agammaglobulinemia.

Amino Acid Sequence↗
PubMed1995

Stimulation of NK-like YT cells via leukocyte function-associated antigen (LFA)-1. Possible involvement of LFA-1-associated tyrosine kinase in signal transduction after recognition of NK target cells.

The YTA-1 anti-LFA-1 alpha mAb activates protein tyrosine kinase (PTK), augments NK cytotoxicity, and induces proliferation of fresh CD3- large granular lymphocytes. We demonstrate here that LFA-1 is physically associated in the YT human NK-like cell line cells with a PTK(s) that is distinct from Src family PTKs such as Lck, Fyn, or Lyn. In vitro kinase assays revealed similar association of protein kinase activity with LFA-1 in normal CD3- large granular lymphocytes. Tyrosine phosphorylation of the proteins associated with LFA-1 drastically increased in YT cells after stimulation with NK-sensitive K562 cells but not with NK-resistant P815 cells. Furthermore, pretreatment of YT cells with TS1/22 anti-LFA-1 alpha and TS1/18 anti-LFA-1 beta mAbs abrogated not only the cytotoxicity against K562 cells but also an increase in tyrosine phosphorylation of LFA-1-associated molecules induced by K562 stimulation. These results provide biochemical evidence that the PTK(s) associated with LFA-1 is involved in the signal transduction that follows the recognition of NK target cells.

Antibodies, Monoclonal↗
PubMed1995

Possible involvement of the transcription factor ISGF3 gamma in virus-induced expression of the IFN-beta gene.

Two virus-inducible transcription factors, IRF-1 and IRF-2 have been identified as an activator and a repressor, respectively, of the type I interferon (IFN) genes. Recent studies with mice carrying null mutations for the IRF-1 or IRF-2 alleles have revealed the existence of IRF-1-dependent and -independent pathways mediating IFN-beta gene induction. Here we report that the expression of an IRF family member ISGF3 gamma is induced upon viral infection in IRF-1-/-, IRF-2-/- embryonic fibroblasts. Furthermore, ISGF3 gamma can bind to a virus-inducible promoter element in the IFN-beta gene. These results suggest that ISGF3 gamma or complex containing ISGF3 gamma is involved in the IRF-1-independent pathway mediating IFN-beta gene regulation.

Amino Acid Sequence↗
PubMed1995

Separation and characterization of Arabidopsis thaliana proteins by two-dimensional gel electrophoresis.

Arabidopsis (Arabidopsis thaliana) proteins were isolated from five tissues (leaf, stem, root, seed and callus), and separated by two-dimensional gel electrophoresis (2-DE). 2-DE was carried out by immobilized pH gradient (IPG) in the first dimension, and by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in the second dimension. With the aid of comigrated five-marker proteins, the patterns of 2-DE gels for each tissue were graphically combined by a computer into a single synthetic image for the integrated Arabidopsis protein spots. The protein spot images, altogether 4763, were characterized by both molecular mass and isoelectric point. Partial amino(N)-terminal sequences of 101 protein spots were analyzed by Edman degradation. Fifty seven proteins were partially sequenced and 46 proteins appeared to have blocked N-termini. Deblocking by hydrazine vapor was carried out on 14 proteins and two of them were found to be pyroglutamyl-blocked N-termini. Forty seven new proteins were found by the present investigation.

Amino Acid Sequence↗
PubMed1995

Calcitonin gene-related peptide and substance P in the pharynx and lung of the bullfrog, Rana catesbeiana.

Indirect double immunofluorescence labelling in the pharynx and lung of the bullfrog, Rana catesbeiana, demonstrated the occurrence, distribution, and coexistence of two neuropeptides. In the pharynx, immunoreactive calcitonin gene-related peptide (CGRP) and substance P (SP) were localized in nerve fibers distributed within and just beneath the ciliated epithelium. In the lung, CGRP and SP were localized in nerve fibers in five principal locations: 1) within the smooth muscle layer in the interfaveolar septa; 2) in the luminal thickened edges of the septa; 3) around the pulmonary vasculature; 4) within, and 5) under the ciliated epithelium. Within the smooth muscle layer in the septa, luminal thickened septa, and around blood vessels, almost all fibers showed coexistence of CGRP and SP. Within and just beneath the ciliated epithelium in the thickened septa, all fibers showed coexistence of CGRP and SP. No immunoreactivity for vasoactive intestinal polypeptide, neuropeptide Y, galanin, somatostatin, FMRFamide, and leucine- and methionine-enkephalins was detected in the nerve fibers within the larynx and the lung. Together with our previous data, the present findings suggest that peptidergic mechanisms are involved in the regulation of amphibian respiratory systems throughout their life.

Animals↗
PubMed1995

Distribution of immunoreactive neuropeptides in the pancreas of the bullfrog, Rana catesbeiana, demonstrated by immunofluorescence.

Indirect double immunofluorescence labelling for eight neuropeptides in the pancreas of the bullfrog, Rana catesbeiana, demonstrated the occurrence, distribution, and coexistence of certain neuropeptides in the exocrine and endocrine pancreas. Immunoreactivity of substance P (SP), calcitonin gene-related peptide (CGRP), vasoactive intestinal polypeptide (VIP), neuropeptide Y (NPY), FMRFamide (FMRF), and galanin (GAL) was localized in nerve fibers distributed between the acini and around the duct system and vasculature of the exocrine pancreas. In these regions, CGRP-immunoreactive fibers were more numerous than those containing the other five peptides. Almost all SP fibers showed coexistence of SP with CGRP, and about one third of fibers also showed coexistence of SP with VIP, NPY, FMRF, and GAL. In the endocrine pancreas, SP, CGRP, VIP, and GAL were recognized in the nerve fibers around and within the islets of Langerhans, and VIP and GAL fibers were more numerous than SP and CGRP fibers. All CGRP fibers, and about half of the VIP and GAL fibers were immunoreactive for SP. NPY- and FMRF-immunoreactive cells were found at the periphery of the islets. These findings suggest that the exocrine and endocrine pancreatic functions of the bullfrog are under the control of peptidergic innervation.

Animals↗
PubMed1995

Distribution of galanin-immunoreactive nerve fibers in the carotid labyrinth of the bullfrog, Rana catesbeiana: Comparison with substance P-immunoreactive fibers.

Immunoreactivity of galanin (GAL) was detected in the nerve fibers distributed within the intervascular stroma of the bullfrog carotid labyrinth. GAL-immunoreactive fibers are numerous, and some are close to the sinusoidal plexus. Most GAL fibers appear as thin processes with some varicosities. A combination of indirect double immunofluorescence labelling and image processing clearly demonstrated that the distribution pattern of GAL fibers is different from that of SP fibers. This indicates that GAL and SP do not coexist in the same nerve fibers. The role of GAL fibers may be different from that of previously reported neuropeptides (substance P, calcitonin gene-related peptide, vasoactive intestinal polypeptide, neuropeptide Y, and others) as a neuromodulator in controlling vascular tone of the labyrinth.

Animals↗
PubMed1995

Differential suppression of axoplasmic transport: effects of light irradiation to the growth cone of cultured dorsal root ganglion neurons.

1. Growth cones of cultured dorsal root ganglion neurons from mice were irradiated using a mercury lamp. 2. The flux of particles of fast retrograde axoplasmic transport decreased promptly after light irradiation without a change in velocity. 3. That of anterograde transport decreased as well, but with a significant latency. The decrease in anterograde flux was attributed to decreased velocity of particles. 4. Video-enhanced contrast microscopy of growth cones revealed transient swelling of growth cones and transient stagnation of particles in growth cones. 5. The longer the neurite, the larger the latency of the change of the anterograde transport; peripheral information was calculated to be conveyed to the cell body at a speed of 6 microns/min. 6. The mechanism of this information conveyance and the export of materials from the cell body are discussed.

Animals↗
PubMed1995

Inhibitors of DNA topoisomerase I and II isolated from the Coptis rhizomes.

A water extract of Coptis chinensis was found to have the ability to stabilize the cleavable complex with mammalian DNA topoisomerase I. As the result of bioassay-guided fractionation, two protoberberine alkaloids, epiberberine and groenlandicine, were identified as active principles with topoisomerase I-mediated DNA cleavage activity in vitro. These two alkaloids did not induce topoisomerase II-mediated DNA cleavage. During further examination of the structurally related protoberberine alkaloids, berberrubine which is produced during the processing of Coptis rhizome as traditional medicine, was identified as a specific inducer of topoisomerase II-mediated DNA cleavage in vitro. These results indicated that protoberberine alkaloids are a chemical family which can induce cleavable complexes with topoisomerases I and II.

Alkaloids↗
PubMed1995

Generalized lichen nitidus appearing subsequent to lichen planus.

A 27-year-old man was seen with multiple, small, shiny papules on his shoulders, upper arms, and trunk, and hyperpigmented violaceous plaques on his feet. The former was diagnosed as generalized lichen nitidus and the latter, as lichen planus. It is not likely that the coexistence of the two diseases in this patient is a fortuitous one, since generalized lichen nitidus is a very rare condition. The association of lichen nitidus and lichen planus suggests that lichen nitidus is closely related to lichen planus and that the two diseases may be different manifestations of essentially the same pathogenetic process.

Adult↗
PubMed1995

Erythema gyratum repens unassociated with underlying malignancy.

A case of erythema gyratum repens occurring in a 62-year-old woman is presented together with a review of the literature. Evaluation and follow-up for the development of malignancy over a 32-month period failed to reveal any evidence of malignancy. Formerly, all cases of erythema gyratum repens were evaluated in terms of an association with an underlying malignant disorder. To date, only sixty cases have been reported in the literature; 14 (23%) were not found to be associated with any neoplasm. Therefore, this term is now also used for cases unassociated with malignancy. Erythema gyratum repens is a cutaneous eruption with a characteristic diagnostic morphology resembling a wood grain pattern.

Eosinophils↗
PubMed1995

Assessment of sextant biopsy of the prostate for detecting cancer prior to therapy in patients clinically diagnosed as benign prostatic hyperplasia.

Pathological results and perioperative morbidity were compared in 199 patients who had undergone prostatectomy and/or biopsy in order to determine the extent to which systematic biopsy is effective for detecting prostate cancer prior to therapy in patients clinically diagnosed as having benign prostatic hyperplasia. Seventeen (8.5%) cancers were detected in 199 patients following surgery and/or biopsy. Digitally-guided biopsy as a means of detecting prostate cancer was found to be just as effective as ultrasound-guided biopsy. Seven (12.5%) cancers were detected in 56 patients who had undergone biopsy and transurethral resection. Preprostatectomy biopsy detected only two of three patients with stage T1b disease. All four stage T1a and one stage T1b failed to be diagnosed. Of 90 patients who had biopsy prior to surgery other than TURP, seven (7.8%) cancers were found. Four of these were advanced. The incidence of postoperative fever > 38.0 degrees C and duration of postoperative pyuria did not differ significantly between groups with or without biopsy. Preoperative biopsy did not contribute to perioperative morbidity. Tumors detected by systematic biopsy are usually large and clinically significant. Positive biopsy results are often diagnostic, but the pathological features of a tumor together with clinical parameters should be considered to reduce the chance of overdiagnosing an insignificant tumor. Sextant biopsy would be most applicable to patients scheduled for any type of therapy other than TURP especially in those with markedly elevated serum PSA levels. This procedure may be beneficial particularly for younger patients with long life expectancy who will benefit from definitive therapy.

Aged↗
PubMed1995

Isolation and mapping of a human gene (PDCD2) that is highly homologous to Rp8, a rat gene associated with programmed cell death.

From a human fetal lung cDNA library we isolated and characterized a human cDNA highly homologous to Rp8, a rat gene associated with programmed cell death. This cDNA, termed PDCD2 (programmed cell death-2), contained an open reading frame of 1032 nucleotides encoding 344 amino acids; it revealed 81% identity in DNA sequence and 83% identity in amino acid sequence with rat Rp8. The gene represented by PDCD2 was expressed in all human tissues examined. We assigned the PDCD2 locus to chromosomal band 6q27 by fluorescence in situ hybridization (FISH).

Amino Acid Sequence↗
PubMed1995

[Clinicopathological study of nonpalpable and nonvisible (stage T1c) prostate cancer].

Clinical and pathologic characteristics of stage T1c disease (nonpalpable and nonvisible cancer) was studied retrospectively in men who underwent radical prostatectomy in order to better understand this disease entity. Findings in stage T1c disease (16 patients) were directly compared with those in stage T2b disease (11 patients). No significant difference was observed between these groups with regard to age, preoperative serum prostatic acid phosphatase level, prostatic weight, numbers of tumor foci, total tumor volume, volume of index cancer and tumor grade (p > 0.05). Preoperative prostate specific antigen concentration was significantly lower in stage T1c group (p < 0.05). Substantially larger number of patients with stage T1c disease had pathologically organ confined disease when compared with T2b group (86.7% versus 45.5%, p < 0.05). Seventy-five percent (12/16) of stage T1c and 90.9% (10/11) of stage T2b disease were considered clinically significant. Most of stage T1c disease is organ confined and clinically significant. Clinical and pathologic features of these tumors are similar to those in T2b disease. Twenty-five percent of stage T1c disease, however, are small and thus may potentially be overtreated. Enhanced detection of prostate cancer achieved with modern technology can lead to undesirable treatment of clinically insignificant tumors. Preoperative diagnostic modalities which can reliably distinguish groups of tumor with different biological potential are needed to overcome this contradiction.

Acid Phosphatase↗