Search PubMed⌕ Search

Biomedical subjects

C Nakamura

Publications and source records attributed to C Nakamura.

At least 127 records · Page 7Linked to original sources
PubMed1988

Assessing alcoholism as a risk factor for acquired immunodeficiency syndrome (AIDS).

Acquired Immunodeficiency Syndrome (AIDS) is characterized by a range of risk factors that determine susceptibility to HIV and the clinical expression of the disease. These include sexual practices, intravenous drug use, and blood exchange. Appropriate preventive measures have been formulated for these risk factors. This paper reviews alcohol abuse as a prominent feature of the homosexual experience, and suggests that it may merit consideration as a risk factor in relation to AIDS. The presumably high prevalence of alcohol abuse among homosexuals and the damaging effects of alcohol on the immune system are discussed as a basis for linking alcoholism, homosexuality, and AIDS. The implications of the potentiating effects of alcohol misuse as the human immunodeficiency virus infiltrates the heterosexual population are presented in terms of high risk populations and the need for additional preventive measures.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Solubilization and Characterization of a Membrane-Bound Auxin-Binding Protein from Cell Suspension Cultures of Nicotiana tabacum.

A membrane-bound auxin-binding protein (MABP) was solubilized by Triton X-100 from cell suspension cultures of Nicotiana tabacum L. Solubilization of MABP was dependent on the detergent concentration and more than 80% of naphthalene-1-acetic acid (NAA)-binding activity was recovered by an optimum concentration of 0.2%. The solubilized MABP was highly heat-unstable and sensitive to protease. The properties of MABP (affinity, temperature dependence, pH optimum, and analog specificity for auxin binding) did not significantly change after solubilization, e.g. the solubilized MABP showed no or very low levels of NAA-binding at 0 to 4 degrees C but showed a high-affinity binding (dissociation constant K(d) = 2.7 +/- 0.3 x 10(-7)m) at 25 degrees C at an optimum pH of 5.0. NAA-binding of the solubilized MABP proceeded very slowly, i.e. a time of half-maximum binding was at least 15 minutes, although the solubilized MABP showed higher rates of association (k(1) = 1.3 versus 0.9 x 10(5)m(-1) min(-1)) and dissociation (k(-1) = 2.2 versus 1.6 x 10(-2) min(-1)) with NAA than the bound MABP. These results show that specific, saturable, and reversible auxin binding to MABP from dicotyledonous N. tabacum differs from that from monocotyledonous Zea mays, and confirm that MABP is distinct from a soluble auxin-binding protein which also is present in N. tabacum.

Journal Article↗
PubMed1988

Correlation between Auxin Resistance and the Lack of a Membrane-Bound Auxin Binding Protein and a Root-Specific Peroxidase in Nicotiana tabacum.

The levels of a membrane-bound auxin binding protein (MABP) and a root-specific peroxidase (RSP) were studied in several tobacco (Nicotiana tabacum L.) cell lines including an auxin-resistant variant. Groups of cell lines were distinguished which behaved differentially with respect to MABP and RSP depending on the hormonal composition of the medium. In cell lines in which there existed a correlation between the presence or absence of MABP and that of RSP both phenotypes were expressed if kinetin (1-2 micromolar) was supplied. In contrast, neither MABP nor RSP could be detected under any hormonal conditions tested in the auxin-resistant variant which retains the ability to differentiate shoots but lacks the ability to differentiate roots. About an eightfold increase in the concentration of MABP and a dramatic increase in the activity of RSP occurred in a transformant by a mutant strain of Agrobacterium tumefaciens lacking an intact cytokinin gene when it was grown on medium containing 1 to 2 micromolar kinetin. A correlation between auxin resistance and the lack of MABP and RSP suggests that MABP might be involved in auxin-mediated root differentiation in tobacco.

Journal Article↗
PubMed1987

Ultrastructural study of initial calcification in the rat subcutaneous tissues elicited by a root canal filling material.

The ultrastructural aspects of initial calcification in the rat subcutaneous tissues elicited by the root canal filling material Vitapex, made up of calcium hydroxide and iodoform with the addition of silicone oil, were studied by means of electron microscopic and cytochemical techniques. The embedded paste caused heterotopic calcifications. These were divided into two types: dystrophic calcification and matrix vesicle calcification which resembled that of bone tissue. These data suggest that Vitapex may be an excellent root canal filling material for differentiation of osteoblasts or cementoblasts from mesenchymal cells in the periodontal ligament.

Animals↗
PubMed1987

Primary spinal epidural Burkitt's lymphoma.

Three Japanese children suffered from symptoms of spinal cord compression, and myelography demonstrated extradural masses compressing the spinal cord at different levels. Decompressive laminectomy revealed epidural tumors which were resected as completely as possible. Histologic pictures of the tumors showed Burkitt's lymphoma, and the diagnosis of primary epidural Burkitt's lymphoma with clinical stage A was made in each case after postoperative examination. Though postoperative radiotherapy and systemic chemotherapy were administered to all patients, they only survived for a short period of time.

Burkitt Lymphoma↗
PubMed1986

Ultrastructural study of calcinosis universalis with dermatomyositis.

Calcinosis universalis associated with dermatomyositis occurred in a 58-year-old woman. Tissues removed from the sublingual region in the patient were studied by ordinary microscopy, electron microscopy, and an electron-microanalytic method. The calcified materials were distributed on collagen fibers and seemed to have a relationship with foci of fibrinoid degeneration. Moreover, globular and/or membranous structures, considered to originate from the degenerate cells of the stroma, were observed in these calcified zones. Some of them contained electron-dense materials. Therefore, the globular and/or membranous structures were thought to be concerned with initial calcification in this case. Furthermore, irregular bone tissue was formed adjacent to the calcified masses. In addition, the calcified materials were identified by X-ray diffraction examination and electron microscopy as hydroxyapatite.

Calcinosis↗
PubMed1986

Neuroepidemiology of acquired immune deficiency syndrome.

Neuroepidemiology is that branch of chronic disease epidemiology dealing with disorders that affect the nervous system. The potential for neurological involvement in the diagnosis and pathogenesis of Acquired Immune Deficiency Syndrome (AIDS) has recently been noted. The following review outlines the spectrum of neurological conditions seen in AIDS patients to date. These conditions include: infectious central nervous system complications of viral, bacterial, fungal or protozoan origin; noninfectious central nervous system complications such as neoplasms or cerebral vascular accidents, and cranial and peripheral neuropathy. The incidence of neurological abnormalities among AIDS cases may be seriously underestimated due to a delay in the presentation of an overt neurological syndrome and/or the overlooking of subtle neurological signs and symptoms in such an overwhelming systemic disease.

Acquired Immunodeficiency Syndrome↗