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Biomedical subjects

K Tsukamoto

Publications and source records attributed to K Tsukamoto.

At least 253 records · Page 14Linked to original sources

A comparison of erythrocytes, lymphocytes and blood plasma as samples in fatty acid analysis for the diagnosis of adrenoleukodystrophy.

We studied the very-long-chain fatty acids of blood plasma, erythrocyte membranes and lymphocytes in 4 adrenoleukodystrophy patients, 5 adrenoleukodystrophy obligate carriers, 12 normal controls and 81 patients with various neurological disorders by high-performance liquid chromatography and compared the reliabilities in the diagnosis of adrenoleukodystrophy of these 3 components of peripheral blood. Of 81 patients with various neurological disorders, 2 myotonic dystrophy and 2 spinocerebellar degeneration patients showed increased ratios of C26:0 to C22:0 in erythrocyte membranes, but not in blood plasma and lymphocytes. None of the 12 normal controls showed increased ratios of C26:0 to C22:0 in erythrocyte membranes, blood plasma and lymphocytes. These results suggest that fatty acid analysis for the diagnosis of adrenoleukodystrophy is more reliable when blood plasma and lymphocytes are used than when erythrocyte membranes are used.

Adolescent↗

Characteristics of mouse lymphoid cells proliferating in vitro by recombinant human interleukin 2 (TGP-3): comparison between normal and nude mice.

Various lymphoid cells obtained from BALB/c and BALB/c nu/nu mice were cultured in vitro with recombinant human interleukin 2 (rIL 2), and the characteristics of responder cells to rIL 2 were analyzed. Spleen cells, lymph node cells, and thymocytes except for bone marrow cells obtained from BALB/c mice remarkably proliferated in response to rIL 2. On the other hand, among lymphoid cells obtained from BALB/c nu/nu mice, only lymph node cells showed significant proliferation by rIL 2. Flow cytometric analysis revealed that mainly two types of lymphoid cells were proliferating in response to rIL 2 in BALB/c mice, i.e., Thy 1+, Lyt 1-, Lyt 2- and Thy 1+, Lyt 1-, Lyt 2+ cells. On the other hand, most of the proliferating cells were Thy 1+, Lyt 1-, Lyt 2- cells in BALB/c nu/nu mice. Treatment with various antibodies plus complement revealed that the majority of IL 2-responsive cells in BALB/c mice were Thy 1+, Lyt 1+, and Lyt 2+, although a minor part of them were Thy 1-, Lyt 1-, and Lyt 2-. On the other hand, a predominant type of the IL 2-responsive cells in BALB/c nu/nu mice were Thy 1-, Lyt 1-, and Lyt 2-, though some were Thy 1+. Nonspecific killer activity against tumor cells increased to variable extents in all of the lymphoid cells of both strains after culture with rIL 2. Our results indicate that mouse responder cells to rIL 2 have the following characteristics. First, the responder cells exist abundantly among spleen, lymph nodes, and thymus in normal mice, though their cell lineages are heterogeneous; one is of T cell lineage and the other of natural killer (NK) cell lineage. Second, nude mice are defective in the responder cells of T cell lineage but not of NK cell lineage. Moreover, the responder cells in nude mice predominantly accumulate in the lymph nodes but not other lymphoid organs.

Animals↗

[Production of human monoclonal auto-antibodies which recognize skin components].

Using human myeloma cell line, LICR-LON-HMy2, and human lymphocytes, we have produced human monoclonal auto-antibodies against skin-components by human-human hybridoma technique. Resulting monoclonal antibodies are classified as follows; 1. Antibodies which recognize cytoplasmic filamentous antigen(s) in epithelial and non-epithelial cells, which are presumably keratin cross-reacting with other classes of intermediate filament(s), 2. Antibody to keratinocyte cellular membrane which is specific to upper epidermal layers, 3. Antibody to sebaceus gland with some cross-reaction in horny layers, 4. Antibody to the innermost cell layer of outer root sheath. The immunoglobulin class of all the antibodies was human IgM. Although pathological roles of these monoclonal antibodies are unknown, it is suggested that auto-antibodies against skin components are more commonly produced in human than previously understood and may be associated with various skin diseases.

Adult↗

[Assembly of the membrane attack complex of complement in pemphigus vulgaris skin].

The time course of the deposition of the membrane attack complex of complement (MAC) in the skin of a case of pemphigus vulgaris was studied by immunofluorescence technique using monoclonal antibodies to human C5, C6, C7, C8, C9 and C5b-9 neoantigens. Biopsy specimens of skin lesions always contained the MAC-related antigens in the ICS areas. No MAC could be detected in the non-lesional skin. It was also noted that MAC could be generated in vitro on cryostat-sectioned normal human skin by the patient serum in the presence of complement. The titer of this complement-fixing antibody rose during the clinically active phase. Results of these studies suggest that complement activation, with subsequent assembly of MAC, may be related to acantholysis in the pemphigus skin.

Complement Membrane Attack Complex↗

Detection and characterization of anti-tumour effector cells in Meth-A-bearing mice treated with recombinant human interleukin 2.

When Meth-A fibrosarcoma-bearing BALB/c mice were injected subcutaneously with 10 micrograms of recombinant human interleukin 2(rIL-2) once a day for 10 days, tumour growth inhibition was in the range of 22-31% of that of the control animals. Anti-tumour effector cells against Meth-A were detected in the spleen cells of the tumour-bearing BALB/c mice injected with rIL-2, using a modified Winn-type neutralization assay with the auxiliary injection of rIL-2. To induce the strongest anti-tumour activity in this assay system, the following were necessary: 1) the effector cells were derived from tumour-bearing BALB/c mice; 2) the donors of the effector cells were injected with rIL-2; 3) the recipient mice in the Winn assay were auxiliarily injected with rIL-2 (a modified Winn assay). The anti-tumour effector activity detected in the modified Winn assay was inhibited by treatment with anti-CD8 or anti-asialo GM1 antibodies plus complement (C), but not completely. We supposed that at least two kinds of anti-Meth-A effector cells with different surface antigens, positive for CD8 and asialo GM1 antigens, were induced in the Meth-A-bearing BALB/c mice injected with rIL-2; these populations seemed to function independently and at least partly as anti-tumour effector cells in this tumour-host system. These spleen cells showed in vitro cytotoxicity against Meth-A cells, which are resistant to NK cells, if the activity was measured in a 24 h 51Cr-release assay in the presence of rIL-2.

Animals↗

Carrier detection for adrenoleukodystrophy by high-performance liquid chromatography.

With a newly devised method of high-performance liquid chromatography (HPLC), we scrutinized lipid extraction of very-long-chain fatty acids of cultured skin fibroblasts from obligate (n = 4) and possible (n = 3) carriers for adrenoleukodystrophy (ALD) in order to establish the best method to detect a carrier for the ALD gene. All four methods (total esterified fatty acids, total fatty acids with acetonitrile-HCl, total fatty acids with methanolic-HCl, and triacylglycerol fraction) were applicable to carrier detection, but from the standpoint of simplicity and sensitivity, the method using total fatty acids with acetonitrile-HCl seemed to be the best. This is the first study of ALD carrier detection in which cultured skin fibroblasts are investigated using HPLC as an analytical method.

Adrenoleukodystrophy↗

[Clinical evaluation of pyeloplasty of ureteropelvic junction obstruction].

Twenty-five of 34 patients who underwent pyeloplasty operation for ureteropelvic junction obstruction were able to be followed up for three months or more after operation. Postoperative results were compared in twenty-six kidneys of these patients according to clinical conditions such as age, duration of indwelling nephrostomy tube and splint catheter, operative method (one-stage or two-stage operation), preoperative urinary tract infections, preoperative grade of hydronephrosis and the postoperative period evaluated. Postoperative results evaluated at three months after operation, revealed no case with excellent improvement. At 36 months after operation excellent improvement rate was 46.7% and there was a significant difference in excellent improvement rate between these times. At 3, 6, 12 and 36 months after operation, improvement rate was 35.7, 55.0, 52.9 and 86.7%, respectively. At 3 and 6 months or more, deterioration rate was 29 and 0%, respectively. It is concluded that evaluation of pyeloplasty should be done at least 6 months after operation and even if renal function is stable at this period, more improvement in renal function can be expected at one year or more after operation.

Adolescent↗

[The recovery of energy metabolism from hypothermic preservation in the rat liver].

Functional recovery of the preserved organ depends on the recovery of energy metabolism. To assess this recovery, adenosine triphosphate (ATP) level and tissue pH were measured by phosphorus nuclear magnetic resonance. Oxygen consumption, bile flow rate and glucose output were also measured before and after preservation. During preservation with Euro-Collins solution at 0 degrees C, ATP signal decreased to noise-level. After preservation, liver was reperfused with modified Krebs-Henseleit solution at 37 degrees C. ATP level of the 6 and 24h preserved liver recovered to 92%, and 76% of the pre-preservation level, respectively. Tissue pH recovered to the pre-preservation level after both 6 and 24h preservation. However, oxygen consumption of the 24h preserved liver was higher than that of the fresh liver. These findings support the idea that the efficiency of oxidative phosphorylation decreases after 24h preservation, but still remains the possibility of increase in ATP hydrolysis by other processes than bile secretion. In another experiment, gluconeogenesis was activated with norepinephrine (NE), and changes in energy metabolism were examined. Glucose output was less increased by NE stimulation in the 24h preserved liver than in the fresh liver. By NE administration, ATP level decreased 5-10% in the fresh liver, and 20-25% in the 24h preserved liver. In the 24h preserved liver, the increment in oxygen consumption induced by NE administration was less than a half of the fresh liver. These results suggest that a supply of ATP is short when an energy demand is increased in the 24h preserved liver, and that this shortage of ATP supply is mainly due to the deterioration of mitochondrial respiration.

Animals↗

Establishment of hybridoma secreting human monoclonal antibody against hepatitis B virus surface antigen.

The HAT (hypoxanthine, aminopterin, thymidine) sensitive and ouabain resistant human B lymphoblastoid cell line TAW-925 was obtained from 6-thioguanine resistant B lymphoblastoid cell line WI-L2. Hybridomas were obtained at a high frequency (10(-4)-10(-5) when TAW-925 was hybridized with cells transformed with Epstein-Barr virus. Using TAW-925 as a parental cell line, we have obtained a hybridoma which stably secretes human monoclonal antibody against hepatitis B virus surface antigen.

Antibodies, Monoclonal↗

Monoclonal antibodies to human interferon-gamma. II: Antibodies with neutralizing activity.

Two types of hybridomas secreting monoclonal antibodies (MAB) with neutralizing activity against human interferon-r (HuIFN-r) were obtained by somatic cell hybridization between mouse myeloma P3UI cells and spleen cells from BALB/c mice immunized with purified recombinant HuIFN-r and a conjugate of a synthetic amino-terminal peptide (residues 4-21) of HuIFN-r and bovine thyroglobulin. One of these MAB recognized the amino-terminal region (residues 4-21) of HuIFN-r, and the other recognized some region in the internal part (residues 22-130) of the molecule. These results suggest that another region, in addition to the amino-terminal region, contributed to the biological activity of rHuIFN-r. A combination of one of these MAB and a previously described MAB directed to the carboxyl-terminal region (residues 131-146) of HuIFN-r enables a quantitative and sensitive assay method of biologically active rHuIFN-r.

Antibodies, Monoclonal↗

The metabolism of roxatidine acetate hydrochloride in rat and dog liver homogenates.

The metabolites were identified by gas chromatography-mass spectrometry (GC-MS). When an equimolar mixture of roxatidine acetate hydrochloride and its deuterated compound, labeled with ten deuterium atoms in the piperidine ring, was incubated with the 9000 X g supernatant (S-9) fraction of either rat or dog liver homogenate, the oxygenated metabolites of the piperidine ring such as the 3-hydroxypiperidine derivative (M1) and the 2-oxopiperidine derivative (M2) were isolated from rats but M2 was not isolated from dogs. These results suggested that the species differences in the metabolism of the piperidine ring in vitro are similar to that in vivo. The deuterium isotope effect (H/D) was 1.34 for M1 and 1.47 for M2 in rats, while the value for M1 in dogs was 1.69. On the other hand, the formation of these oxidative metabolites was inhibited by carbon monoxide in incubations using hepatic microsomes, suggesting that the reaction was catalyzed by cytochromes P-450.

Animals↗