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Biomedical subjects

M Ohta

Publications and source records attributed to M Ohta.

At least 1,369 records · Page 76Linked to original sources

Infantile neuroaxonal dystrophy. Ultrastructural study of peripheral nerve.

Ultrastructural study of the biopsied sural nerve in a case of infantile neuroaxonal dystrophy was made. The characteristic change in the ballooned axons is an accumulation of membranous profiles associated with mitochondria, glycogen like granules, dense bodies, vesicles and electron lucent material. The membranous profile is classified into three morphological types and discussed on each of them. Probably tubulomembranous profile of the first type is most common and may be cardinal deposit in this condition. These membranous structures of various types might be, however, only different manifestations occurring on the same morbid process. Enormous amount of glycogen like granules and mitochondria might be related to the metabolic derangement of carbohydrate in the ballooned axons. Electron lucent material we observed was not described in the previous papers on this condition. We added one more example showing that nerve biopsy is helpful to confirm the diagnosis in infantile neuroaxonal dystrophy.

Axons↗

Clinical observations of juvenile nonprogressive muscular atrophy localized in hand and forearm.

Twenty-seven patients with juvenile nonprogressive muscular atrophy localized in the hand and forearm were analyzed. The clinical characteristics were juvenile male occurrence, insidious onset, specific distribution of localized muscular atrophy and a stationary course. On electromyography, denervation voltage (or giant NMU) is found in the atrophied muscles and sometimes in contralateral nonatrophied ones. Sensory disturbance was not remarkable. Although the etiological factor was not known, strenuous exercise of arms in sports was noted frequently in the history.

Adolescent↗

Adjuvant action of capsular polysaccharide of Klebsiella pneumoniae on antibody response. V. Further biological properties of the active substance.

The neutral fraction (neutral CPS-K) of Klebsiella pneumoniae capsular polysaccharide (CPS-K) from type 1, Kasuya strain, has already been reported as the active substance responsible for the strong adjuvant effect of CPS-K. The present results demonstrate that neutral CPS-K exhibits further common biological activities with lipopolysaccharide (LPS) isolated from Salmonella enteritidis. The intensity of the lethality in mice of neutral CPS-K by the intraperitoneal route is very similar to that of LPS. Its lethality for mice by the intravenous (i.v.) route is significantly stronger than that of LPS, because the degree of increase in the sensitivity to their lethality by i.v. challenge is smaller for LPS than for neutral CPS-K. The intensity of the pyrogenicity of neutral CPS-K in rabbits is approximately one-tenth of that of LPS as judged by the minimal pyrogenic doses and fever indices. The skin-preparatory potency of neutral CPS-K for the dermal Shwartzman phenomenon in rabbits is also approximately one-tenth of that of LPS compared on the basis of the minimal skin-preparatory doses. When injected i.v., neutral CPS-K exhibits a provocative effect on hemorrhagic reactions in skin sites prepared with neutral CPS-K or LPS.

Adjuvants, Immunologic↗

Immunotherapy of cancer with cell wall skeleton of Myocabacterium bovis-Bacillus Calmette-Guérin: experimental and clinical results.

Adjuvant and antitumor activities of CWS prepared from cells of mycobacteria, nocardia, and corynebacteria were examined. Oil-attached CWS of M. bovis BCG (BCG-CWS) stimulated the generation of cell-mediated cytotoxic effector cells in mice. Tumor growth was suppressed in mice inoculated intradermally with a mixture of oil-attached CWS and living tumor cells. Systemic and specific tumor immunity was demonstrated in mice in which tumor growth was suppressed. Tumor growth was also suppressed by oil-attached CWS of BCG or N. rubra in autochthonous autografts of spontaneous mammary adenocarcinoma and methylcholanthrene-induced fibrosarcoma in mice. The intravenous injection of oil-attached BCG-CWS prevents the appearance of lung cancer in rabbits by the instillation of chemical carcinogens. It was also shown that treatment with oil-attached BCG-CWS was able to elevate the immunologically depressed state of tumor-bearing mice to a normal level, as determined by a cell-mediated cytotoxicity assay that empolyed chromium release as the standard. Preliminary results suggest that oil-attached BCG-CWS is useful as an immunotherapeutic agent for both lung cancer and for malignant melanoma, leukemia, Hodgkin's disease, and other neoplastic diseases and that this agent operates without any significant complications.

Animals↗

Cytotoxic activity of lymphocytes to bronchogenic carcinoma cells in patients with lung cancer.

Cytotoxicity of peripheral blood lymphocytes against a cultured cell line QG-56 of a bronchogenic squamous cell carcinoma was studied by a microcytotoxicity test in 33 cases of bronchogenic carcinoma. An augmented cytotoxicity was detected in the patients in early stages of the disease as compared to normal controls or the patients carrying other types of tumors. The cytotoxicity declined as the stages of cancer advanced. The patients with high degree of cytotoxicity appeared to show better clinical course after radiotherapy.

Carcinoma, Bronchogenic↗

[An experimental study of the effects of drilling with dental high speed turbine on culture cells (in vitro) (author's transl)].

A drilling at 500 000 R.P.M. with a dental high speed turbine was made either to a tissue culture bottle or to a test tube, in which mouse L fibroblasts were grown for 2 days with YLH medium supplemented with 10% bovine serum, in order to examine the effects of high speed drilling to the cells in vitro, Experiments were carried out with the following three conditions; (1) Drilling of outer surface of the glasswares at the inner surface on which the cells were attached, with a water coolant, (2) Drilling of the same place without a water coolant, and (3) Drilling of a remote area of the glasswares where no cells were grown. The last experimental condition permitted to give a sole effect of vibration accompanied with the drilling. Rates of cell multiplication and morphological observation were obtained on 2 days and 5 days after the glasswares were drilled. Rates of cell multiplication showed no change between the experimental conditions and control. This means that heat generation, vibration and/or their compound effects during drilling did not deter cells from growing. Morphological change of the cells due to the drilling was parallel to the results of cell multiplication except the drilling without a water coolant. When drilled without a water coolant, the cells around the drilled area was deteriorated and died after 24 hours. However, most of the cells away from the drilled area were not affected. The present results can not directly apply to the drilling in dental clinic, since in vivo condition has more complicated situation, some of which can not be simulated in in vitro environment. However, the in vitro results can surely be important information in resolving drilling effects in vivo.

Cell Division↗

Comparative studies on the actions of antigen and polyclonal B-cell activator in differentiation and proliferation of B-cells and B memory cells.

Using the capsular polysaccharide of Klebsiella pneumoniae (CPS-K) as a polyclonal B-cell activator (PBA) and sheep red blood cells (SRBC) as a T cell-dependent antigen, we compared the ability of PBA and antigen to differentiate (generate antibody-forming cells, AFC) and proliferate (generate immunological memory) virgin B cells and B memory cells. In vitro CPS-K induced the differentiation of IgM virgin B cells, IgM B memory cells and IgG B memory cells to AFC, as well as or better than SRBC. The differentiation of B memory cells to AFC by CPS-K did not require the participation of macrophages or T cells, whereas the action of SRBC depended strictly upon the helper actions of these cells. The responsiveness to CPS-K and SRBC of normal and antigen-primed spleen cells as judged by anti-SRBC PFC responses in vitro was markedly decreased after stimulation of virgin B cells and B memory cells in vivo by CPS-K injection into normal or primed mice but greatly increased after the injection of SRBC. The decrease in the responsiveness to CPS-K of spleen cells from mice treated with CPS-K appeared principally due to exhaustion of the functions of B cells and B memory cells. From the present data it has been concluded that the signals required for the differentiation and proliferation of B cells of B memory cells are different from each other, the signal for differentiation being provided by either antigen (SRBC) or PBA (CPS-K), while the signal for proliferation only by antigen.

Animals↗

Immunotherapy of human lung cancer with BCG cell-wall skeleton.

Effect of BCG cell-wall skeleton (BCG-CWS) on the recovery of responsiveness of lymphocytes and the survival period was studied in patients with lung cancer. (a) Responsiveness of lymphocytes as demonstrated by proliferative response to phytohemagglutinin (PHA) or microcytotoxicity test with cultured cells of a bronchogenic carcinoma was depressed in the patients at later stages of cancer and it was restored by treatment with BCG-CWS in many of such patients. (b) Survival period of the patients at later stages such as III or IV was prolonged by treatment with BCG-CWS. Such an effect was detected even in the patients with carcinomatous pleuritis. (c) A close correlation was found between the reactivity such as PHA response or cytotoxicity and clinical course of the patients given BCG-CWS. Assay system with PHA response and microcytotoxicity test appears to be reliable in anticipating the prognosis and in following clinical course after the BCG-CWS treatment.

Adenocarcinoma↗

Effect of fasting on two postheparin plasma triglyceride lipases and triglyceride removal in obese subjects.

A new method was used for selective measurement of lipoprotein lipase and hepatic lipase in human postheparin plasma. Hepatic lipase was assayed in 1.0 M NaCl withour addition of serum, and the activity of lipoprotein lipase was determined in 0.1 M NaCl after immunoprecipitation of hepatic lipase with specific antiserum. The activity of both these enzymes and the total lipolytic activity were measured in plasma samples taken during a 4-h infusion of heparin. Each of the activities was related to basal serum triglyceride concentration and to the fractional removal constant (K) of Intralipid in 13 obese subjects before and after prolonged fasting. During a normal isocaloric diet the lipolytic activities showed a biphasic response to heparin infusion in all subjects. A peak activity was reached within 30 minutes ("early response") and thereafter the lipase activities decreased to a constant level maintained during the rest of the heparin infusion ("late response"). The early response of lipoprotein lipase showed a significant inverse correlation with the basal serum triglyceride level (r = -0.85) and a significant positive correlation with the fractional removal rate of Intralipid (r = 0.84). The late response of lipoprotein lipase was not related to either of these parameters. The early response of hepatic lipase was not correlated with basal triglyceride concentration or Intralipid removal, whereas the late response of this enzyme showed a significant negative correlation with the removal rate of Intralipid (r = -0.82). After fasting for several days the acute response of all lipolytic activities to heparin was markedly decreased or totally abolished, but the magnitude of the late response was similar to that seen in the fed state. The fractional removal rate of Intralipid was slightly increased by starvation. All correlations between postheparin plasma lipases and serum triglyceride concentration and removal disappeared in fasting subjects. It is concluded that the rapidly releasable lipoprotein lipase probably reflects the activity of the tissue enzyme(s) which is responsible for the primary removal of very low density lipoprotein (VLDL) triglycerides and chylomicrons. It is probable that this component of the postheparin plasma lipolytic activity is derived from the endothelial lipoprotein lipase pool. This enzyme plays a key role in the efflux of plasma triglycerides under normal conditions, and it is thus one determinant of plasma triglyceride level. Prolonged fasting obviously changes the triglyceride removal sites and mechanism but does not impair the removal efficiency.

Adult↗

Giant axonal neuropathy. A clinical entity affecting the central as well as the peripheral nervous system.

An 8-year-old girl had progressive muscle weakness and a unique posture of the lower limbs, areflexia, distal sensory impairment, and remarkably kinky hair. Histologic examination of the sural nerve showed giant axons filled with neurofilamentous masses. The clinical and histologic findings resembled those of recent cases reported as "giant axonal neuropathy." Our patient's precocious puberty, Babinski's sign, and electroencephalographic abnormalities suggested central nervous system involvement. Two cases previously reported and the present one appear to represent a new clinical entity that affects the central and the peripheral nervous system.

Axons↗

Chronic inflammatory polyradiculoneuropathy.

The diagnostic criteria, natural history, nerve conduction characteristics, pathology, laboratory features, and efficacy of corticosteroid treatment have been evaluated personally in 53 patients with chronic inflammatory polyradiculoneuropathy (CIP) who were followed up for an average of about 7.5 years. These were patients whose monophasic neurologic deficit had not crested by 6 months, patients with recurrences, and patients with a steady or stepwise progression. The typical features of CIP include absence of an associated disease, frequent history of preceding infection or receipt of foreign protein, and tendency to involve cranial, truncal, and proximal as well as distal limb structures and to have diffusely slow conduction velocity of peripheral nerves. The most marked slowing is often very proximal. The pathologic features include serous edema, mononuclear cell infiltrates (especially in perivascular areas, but without evidence of vasculitis), macrophage-induced segmental demyelination, and hypertrophic neuritis. If our patients are representative, complete recovery occurs only infrequently; about 60% of patients are able to be ambulatory and work, 25% become confined to a wheelchair or become bedridden, and approximately 10% die from their disease. Although the bulk of the pathologic changes affect spinal roots and proximal nerves, the brain and spinal cord may be involved also. Degeneration into linear rows of myelin ovoids is the predominant type of myelinated fiber degeneration of the sural nerve at the ankle.

Adolescent↗