Biomedical subjects
Publications and source records attributed to K Fujiwara.
Desmoplastic fibroma of the bone appears in a wide variety of bones but rarely involves the spine. A 24-year-old male with desmoplastic fibroma of the axis treated by complete resection and posterior spinal fusion is reported. There was no recurrence of the tumor three years after surgery. Complete resection and reconstructive surgery for spinal instability are recommended for this benign spinal tumor.
As one method of multidisciplinary treatment for cancer of the uterine cervix, a combination IAC using CDDP and 5-FU was applied. Six operable and three inoperable, advanced patients were treated with a single 100-120 mg/body IAC bolus of CDDP followed by a continuous IA infusion of 2,500 mg/body of 5-FU. This was combined with surgical therapy in the former group and radiotherapy in the latter group. In operable cases, the extirpated tissues were examined histopathologically for effects of the combination IAC. Microscopic findings included atrophy and swelling of the cancer cell nucleus, plus variable diffused reduction of the cancer cell nest accompanied by vacuolation of the cytoplasm. In inoperable cases, observations carried out by graphical scintigram, and clinical investigation at 10 days after the IAC, indicated improved conditions. Among the adverse reactions, renal dysfunction recovered two weeks after IAC. No evidence of severe myelosuppression was observed. Therefore, IAC with CDDP and 5-FU, plus surgery or radiotherapy, against carcinoma of the cervix had favorable laboratory and clinical results.
A pyridoxal 5'-phosphate-containing peptide which contained 54 amino acid residues was isolated from chicken liver P-protein of the glycine cleavage system following reduction with NaB3H4, carboxymethylation, and proteolysis with lysylendopeptidase. Two peptides which comprise the two halves of the phosphopyridoxyl peptide were isolated from apo-P-protein. Sequence analysis of these three peptides provided the primary structure of the phosphopyridoxyl peptide and revealed that the cofactor is linked to Lys-35. The pyridoxal 5'-phosphate-binding site has the His-Lys(PLP)-X structure characteristic of known pyridoxal 5'-phosphate-dependent amino acid decarboxylases, tryptophan synthase, and serine hydroxymethyltransferase.
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T-protein, one of the components of the glycine cleavage system, catalyzes the synthesis of the H-protein-bound intermediate from methylenetetrahydrofolate, ammonia, and H-protein having a reduced lipoyl prosthetic group (Okamura-Ikeda, K., Fujiwara, K., and Motokawa, Y. (1982) J. Biol. Chem. 257, 135-139). Spectroscopic studies indicated that the utilization of methylenetetrahydrofolate occurred only in the presence of the three substrates, indicating the formation of a quaternary complex. The amount of methylenetetrahydrofolate consumed was equal to that of methylene carbon attached to H-protein. Steady-state kinetic studies show that the reaction proceeds through an Ordered Ter Bi mechanism. Reduced H-protein is the first substrate that binds T-protein followed by methylenetetrahydrofolate and ammonia. The order of release of products is tetrahydrofolate and the H-protein-bound intermediate. Km values for H-protein, methylenetetrahydrofolate, and ammonia are 0.55 microM, 0.32 mM, and 22 mM, respectively.
A heterobifunctional crosslinking agent N-[beta-(4-diazophenyl)ethyl]maleimide (DPEM) was newly synthesized and characterized to possess the maleimide group with a stability greater than that previously reported for N-(4-diazophenyl)maleimide. Using the peptide hormone neurotensin (NT) as a model hapten, DPEM was used in the conjugation reaction with bovine serum albumin (BSA) and with beta-D-galactosidase (beta-Gal) in developing an enzyme immunoassay (EIA) for NT. The NT-DPEM-BSA conjugate elicited anti-NT antibodies in rabbits and the NT-beta-Gal conjugate behaved as an enzyme marker of NT in the EIA. The EIA developed double antibody was reproducible and sensitive in detecting NT at concentrations as low as 30 fmol per tube. The specificity of anti-NT serum seems to be primarily toward the carboxy-terminal region of NT, showing cross-reactions with such NT fragments as NT2-13, NT8-13, and NT1-8 for 120, 22, and less than 0.1%, respectively. The utility of this assay was also demonstrated by measuring the NT immunoreactivity in several rat organs. DPEM could be useful for developing EIAs for other peptide hormones (even those which contain neither a free amino group nor a free carboxyl group), using the imidazole, phenolic, or indole group(s) of amino acids as a binding site for carrier proteins.
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The F(ab')2 fragments were prepared from three monoclonal antibodies (MAbs) reactive with either peplomer glycoprotein (E2) or nucleocapsid protein (NP) of a low-virulence mouse hepatitis virus (MHV), MHV-NuU. All the three MAbs could protect mice from challenge infection with virulent MHV-2, whereas only one of the anti-E2 MAbs was capable of neutralizing the virus in vitro. The F(ab')2 fragment of neutralizing anti-E2 MAb was shown to protect mice from challenge infection, but those of non-neutralizing anti-E2 and anti-NP MAbs were not protective.
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Polyamines are low molecular weight organic cations, necessary for cell proliferation and implicated in numerous biochemical events. Their light microscopical distribution has previously been studied by the use of two fluorescence cytochemical methods. With the aid of an antibody recognizing the two main polyamines, spermidine and spermine, we now report on their immunocytochemical localization in animal tissues. Polyamine immunocytochemistry was found to require very well controlled conditions of fixation in order to prevent diffusion, loss and redistribution of endogenous polyamines. Moreover, in certain cellular compartments, polyamine immunoreactivity was masked by proteins, necessitating proteolytic pretreatment of sections prior to staining. The fluorescence cytochemical methods, employing low molecular weight reagents, did not require such unmasking. The results of the optimized immunocytochemical procedure were in complete agreement with the results obtained by the fluorescence cytochemical methods. Although fluorescence cytochemistry, is simpler and quicker to perform than immunocytochemistry, the latter technique may be extended to studies of polyamines at the ultrastructural level.
A human erythroleukemia cell line, K-562 T1, was adapted to a protein-free chemically defined medium; that is, the medium does not contain any proteins such as exogenous hormones, growth factors, serum and serum albumin. The K-562 T1 cells which can proliferate in a protein-free medium are one of the model systems suitably supporting the autocrine hypothesis, which claims that cancer cells produce and respond to their own growth factors. The K-562 T1 cells were cultured in a protein-free medium at large scale and the growth factors were purified from the conditioned medium. It was found that K-562 T1 cells produce at least two growth factors; one is LGF-I (leukemia-derived growth factor-I) which can stimulate the proliferation of a wide range of human leukemia cell lines and the other is LGF-II (leukemia-derived growth factor-II), which can contribute to the growth of fibroblasts. LGF-I was purified using QAE-Sephadex, Bio Gel P-60 and Mono S FPLC. The purified protein was found to be homogenous by SDS-polyacrylamide gel electrophoresis and NH2-terminal sequence analysis. The molecular weight of LGF-I was 20,000 by SDS-polyacrylamide gel electrophoresis. The 30 NH2-terminal residues of LGF-I are the same as that of ubiquitin. Ubiquitin is a protein found in eukaryotic cells with molecular weight of 8,600. In the nucleus ubiquitin is conjugated to histone 2A to form the nuclear protein A24 which may play a role in regulation of chromatin structure, and in the cytoplasm is part of an ATP-dependent non-lysosomal proteolytic pathway. However, its physiological significance has not yet been fully resolved. Ubiquitin purified from bovine thymus did not show cell proliferating activity for any cells tested. The results suggest that LGF-I is a new autocrine growth factor with a molecular weight of 20,000 daltons, containing ubiquitin at the NH2-terminal end.
Pericytes and endothelial cells from the same sample of adult rat lung have been separately established in culture by use of selective growth media. The endothelial cells are positive and the pericytes negative for angiotensin-converting enzyme activity and tissue plasminogen activator. Morphologically in culture, the pericytes are similar to pericytes from bovine retina and other sites and show positive immunofluorescence to both human platelet (non-muscle) myosin and smooth muscle myosin. In this respect they resemble smooth muscle cells grown from the rat main pulmonary artery, but lack the myofilaments and dense bodies characteristic of muscle cells. Lung endothelial cells and fibroblasts are positive only for platelet myosin. Pericytes in culture demonstrate an unusual growth response to endothelial substrate, obtained by removing confluent endothelial monolayers with nonionic detergent or alkali. When plated onto this material at low density, pericyte growth is inhibited. By contrast, the substrate stimulates the growth of endothelial cells and has no effect on smooth muscle cells. Initial attachment of endothelial cells and pericytes to the substrate is similar.
A case of proliferative myositis of the buccinator muscle is reported. To our knowledge, the present case is the second reported in the oromaxillary region. From immunohistochemical and electron microscopic studies, it seems likely that the ganglion-like cells are derived from myofibroblasts or macrophages rather than from striated muscle cells.
Occupational asthma caused by isonicotinic acid hydrazide (INH) inhalation occurred in a 26-year-old female hospital pharmacist after symptoms of allergic rhinitis. Intradermal, inhalation, and Prausnitz-Küstner tests were performed with INH dissolved in saline, INH dissolved in the subject's serum and incubated at 25 degrees C for 4 hours, and an INH conjugate with human serum albumin. An INH conjugate with bovine serum albumin was also used in the prick tests alone. All preparations caused rapid positive skin reaction in the patient. Prausnitz-Küstner tests on the subject's mother were also rapidly positive. Furthermore, positive results were obtained not only in the inhalation tests with the three antigens but also in the environmental provocation tests. These results strongly suggested that the asthmatic symptoms of the subject were not caused by physical irritation from INH or other drugs and might be mediated by an IgE antibody specific to INH, a suggestion subsequently confirmed by in vitro enzyme-linked allergosorbent test for the antibody previously reported. This is the first precise description of INH-induced bronchial asthma, and the four kinds of INH preparations used in these tests might be very useful as tools of clinical diagnosis in INH allergy.
Detection by in vitro serologic techniques of circulating antibody directed against isonicotinic acid hydrazide (INH, known as isoniazid) in humans has not been reported. In the past few months, however, sera from a patient with a recent history of isoniazid hypersensitivity of the immediate type have been studied, and reaginic antibodies (IgE) specific to INH were detected by means of an enzyme-linked allergosorbent test. Preliminary enzyme-linked allergosorbent tests also demonstrated that INH-specific IgE occurred in the serum of two of 150 patients with tuberculosis who had been treated with INH.
A cell-surface modulator of DNA synthesis by cultured rat hepatocytes was studied in relation to the liver regeneration process. When rat hepatocytes isolated 24 h after partial hepatectomy were cultured, the first burst of DNA synthesis peaked at 5-8 h and declined until 24 h, followed by the second burst. Rat liver plasma membranes added 2 h after plating inhibited only the second burst, while in the case of the normal hepatocytes where the DNA synthesis began to increase after 5 h, this inhibition was observed at 16 h but not at 8 h. The inhibition did not differ when the membranes obtained from regenerating livers 12 h after partial hepatectomy were used. Epidermal growth factor binding to the cultured hepatocytes was not hindered by the membranes. These results suggest that the modulator inhibits hepatocyte proliferation at the early G1-phase of the cell cycle and that its action might be controlled by other factors in the process of liver regeneration.