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Biomedical subjects

K Takatsuki

Publications and source records attributed to K Takatsuki.

At least 289 records · Page 16Linked to original sources

[Studies on the role of leukocytes in the activation of intravascular coagulation in septicemia].

To elucidate the role of leukocytes in intravascular clotting in patients with septicemia, plasma levels of thrombin-antithrombin III complex (TAT), soluble fibrin monomer complex (SFMC) and fibrinogen (Fbg) were determined in 33 patients with septicemia. Twenty out of 33 patients revealed a marked leukopenia (leukocyte count was less than 1,000/microliters) due to suppression of hematopoiesis by the administration of chemotherapeutic agents for the treatment of hematological malignancies. Thirteen out of 33 patients showed normal or increased leukocyte counts. Plasma levels of TAT and SFMC in septicemic patients with leukopenia were significantly lower than those in patients whose leukocyte counts were higher than 1,000/microliters. Plasma fibrinogen levels were significantly lower in patients whose leukocyte counts were higher than 1,000/microliters than those in patients with leukopenia. Plasma TAT levels were found to correlate well with the number of leukocytes in these patients with the correlation coefficient (R) of 0.67 (p less than 0.001). Significantly high positive correlation was observed between plasma TAT levels and the number of monocytes (R = 0.92, p less than 0.001). Significant correlation was also observed between plasma SFMC levels and the number of monocytes (R = 0.72, p less than 0.001). No significant correlation was found between the number of platelets and TAT levels. These findings suggest that leukocytes (especially monocytes) play a critical role in activating intravascular coagulation in septicemic patients.

Antithrombin III↗

[Plasma concentration of polymorphonuclear leukocyte elastase-alpha 1-proteinase inhibitor complex in patients with gastric ulcer].

To test the possible participation of activated leukocytes in the pathogenesis of gastric ulcer, plasma levels of polymorphonuclear leukocyte-elastase-alpha 1-proteinase inhibitor complex (PMN-EC), a discerning indicator for the activation of leukocytes, were determined in patients with gastric ulcer. Plasma levels of PMN-EC in patients with gastric ulcer (185.2 +/- 21.6 micrograms/l, mean +/- S.E.M.) were significantly higher than those in normal healthy subjects (67.6 +/- 4.4 micrograms/l, p less than 0.01). On the other hand, plasma levels of C-reactive protein and sialic acid increased in only 17.8% and 7.1% of patients with gastric ulcer, respectively. No significant correlation was observed between PMN-EC and the plasma levels of CRP or sialic acid. Plasma levels of PMN-EC decreased with the healing of the ulcerative lesion as judged by gastro-endoscopic observation. These findings suggested that activation of leukocytes might deeply be correlated with the pathologic mechanism of gastric ulceration and the measurement of PMN-EC might be useful for monitoring the patients with gastric ulcer.

Humans↗

[Administration of recombinant erythropoietin to a patient with malignant lymphoma who refused blood transfusion].

A 30-year-old female patient with malignant lymphoma was admitted to the hospital because of large mass in the left pelvic cavity and of severe anemia. Since she had refused blood transfusion (Jehovah's witness), recombinant human erythropoietin (Epo) was used together with both chemotherapy and irradiation; this led to rapid recovery of the anemia and marked reduction of the mass volume. These findings may suggest the possible application of Epo administration as a supportive therapy in treatment of malignancy.

Adult↗

[Sick sinus syndrome as an initial symptom of B-cell malignant lymphoma involving the heart].

We present a rare case of B-cell malignant lymphoma in whom lymphoma cell infiltration into heart caused sick sinus syndrome (S.S.S) as an initial symptom and premortem diagnosis of heart involvement was made. A 62-year-old woman was admitted to the orthopedic hospital because of pain in the lower extremities and discomfort in the chest. Chest roentgenogram showed an enlarged cardiac shadow and electrocardiogram (ECG) showed a sinus node dysfunction. A diagnosis of S.S.S. was made by the examination of sinus node recovery time. Myelography disclosed complete block between the 3rd and 4th lumbar vertebra. Pacemaker was inserted and laminectomy was done. The diagnosis of malignant lymphoma was made by the cytological study of the resected tissue. Gallium isotope study showed markedly increased isotope uptake in heart and abdomen. After chemotherapy the enlarged shadow of heart reduced in size and the uptake of gallium disappeared. ECG showed a sinus regular rhythm. Afterwards her general condition got worse and leukemic convergence of malignant lymphoma occurred. Monoclonal antibody study of these cells disclosed positive CD 19 (OK B1), CD 20 (OK B4), and surface IgM-lambda.

Antineoplastic Combined Chemotherapy Protocols↗

Monoclonal antibody to galactosylceramide: discrimination of structural difference in the ceramide moiety.

A mouse monoclonal antibody (mAb) was developed against monohexaosylceramide. This mAb differentially reacted on thin-layer chromatograms with 3 types of galactosylceramide (GalCer) obtained from bovine brain. Structural analysis of the 3 glycolipids revealed that they consisted of the same galactose and sphingosine but of apparently different fatty acids. Among the GalCers, the mAb reacted with teh two GalCers which contained alpha-hydroxy fatty acids, but not with GalCer composed of nonhydroxy fatty acids. These findings suggest that not only that the mAb discriminated the fatty acid composition in the ceramide moiety of GalCer, but also that the ceramide structure defines the immunological epitope as it is known to do for the carbohydrate moiety of glycosphingolipid.

Animals↗

Cytotoxicity of interleukin 2-toxin toward lymphocytes from patients with adult T-cell leukemia.

The inhibitory effect of a diphtheria toxin-related interleukin 2 fusion protein, IL-2-toxin, on protein synthesis in adult T-cell leukemia/lymphoma (ATL) cells was examined in vitro. Peripheral blood ATL cells from 12 patients (six acute type, four chronic type, and two smoldering type ATL) and the lymph node cells from three ATL patients (two acute type and one lymphoma type ATL) were examined. At a concentration of 10(-8) M, IL-2-toxin inhibited protein synthesis by 60 to 98% in lymph node ATL cells, whereas protein synthesis in peripheral blood ATL cells was inhibited from 20 to 57% in acute type, and from 3 to 13% in chronic type. In contrast, IL-2-toxin had no measurable effect on T-cells from either patients with smoldering type ATL or normal controls. The cytopathic effects of IL-2-toxin were blocked by the addition of anti-CD25 monoclonal antibody, suggesting that the inhibition of protein synthesis in target cells was mediated by the IL-2 receptor (IL-2R). The degree of inhibition of protein synthesis, however, was not closely correlated with expression of CD25 antigen (low-affinity Mr 55,000 glycoprotein, IL-2R, Tac antigen) on ATL cells. There was an apparent correlation between the degree of inhibition and the rate of protein synthesis in ATL cells. We demonstrate that ATL cells from patients with acute or lymphoma type disease were more sensitive to IL-2-toxin than cells from chronic or smoldering disease. These findings suggest that the high affinity IL-2R present on acute and lymphoma type ATL cells may serve as a target for therapy with this recombinant chimeric toxin.

Adult↗

The prevalence of antibody to p42 of HTLV-I among ATLL patients in comparison with healthy carriers in Japan.

A gene product (p42) of the long open reading frame, now termed tax, of the viral genome of human T-cell leukemia virus type I (HTLV-I) may be related to the transformation of T cells in adult T-cell leukemia-lymphoma (ATLL). To evaluate its association with the disease, we compared the prevalence of antibody to p42 in sera obtained from 105 HTLV-I carriers and 64 ATLL patients from southwest Japan. The prevalence of the anti-p42 antibody reactivity was 63% among carriers and 31% among cases. The cases were more than 3 times as likely to lack antibody to p42 than carriers, the relative odds (OR) = 3.4, p = 0.001. When the samples were tested for antibody against p24, the most immunogenic core protein, the prevalence was somewhat higher among carriers (65%) than in cases (52%), but not significantly so (p = 0.15). Among the healthy carriers, the correlation between the prevalence of both antibodies was high (p = 0.001), and only 25% of those who had antibody to p24 lacked antibody to p42. However, among the cases, reactivity to both antigens was independent (p = 0.52), and 65% of those with antibody to p24 lacked antibody to p42, OR = 6.3, p = 0.0004. Thus the strongest serologic marker of ATLL following diagnosis was lack of reactivity to p42, particularly among those subjects with anti-p24. Whether this altered response is present prior to disease remains to be determined.

Autoradiography↗

Ca2+ influx stimulated by vasopressin is mediated by phosphoinositide hydrolysis in rat smooth muscle cells.

The mechanism of Ca2+ influx stimulated by arginine vasopressin (AVP) was studied in cultured rat smooth muscle cells. AVP stimulated 45Ca2+ influx even in the presence of nifedipine, a Ca2+ antagonist that inhibits voltage-dependent Ca2+ channel. NaF, a GTP-binding protein activator, mimicked the AVP-stimulated 45Ca2+ influx. The 45Ca2+ influx stimulated by a combination of AVP and NaF was not additive. The affinity of AVP receptor was decreased by guanosine 5'-O-(3-thiotriphosphate). Pertussis toxin failed to affect the AVP-stimulated 45Ca2+ influx. AVP did not stimulate cAMP production, but increased inositol trisphosphate generation. Both AVP-stimulated 45Ca2+ influx and inositol trisphosphate generation were inhibited by neomycin, a phospholipase C inhibitor, in a dose-dependent manner, and the patterns of both inhibitions were similar. These results suggest that, in rat smooth muscle cells, AVP-stimulated Ca2+ influx is mediated exclusively through phosphoinositide hydrolysis.

Animals↗

[Radioimmunoassay of vasopressin in unextracted random urine; clinical application for screening of central diabetes insipidus].

The concentration of unextracted urinary arginine vasopressin (UAVP) was directly measured by high-sensitive radioimmunoassay (AVP-RIA Kit, Mitsubishi Petrochemical Co., Ltd.). Urine was diluted to eliminate interference of nonspecific substance without prior extraction. When urine aliquots were diluted in 4 to 32 fold in assay buffer, the relationship between UAVP concentration and dilution ratio corresponded exactly in a linear regression line. The elution pattern on Sephadex G-25 of UAVP immunoreactivity was identical with that of synthesized AVP. The AVP concentration in unextracted urine was not significantly different from that of extracted urine by Sep-Pak C18 column (Water Associates, Milford MA). The mean recovery of added AVP to urine specimens was 101.1 +/- 9.8% (mean +/- SD). The immunoreactivity of UAVP was not modified by either albuminuria (50 and 100 mg/dl) or glycosuria (1000 g/dl). Mean coefficients of variance between-assay and within-assay were 8.3% and 6.6% respectively. In normal subjects (n = 28), significant correlation was observed between UAVP concentration and simultaneously measured plasma AVP (r = 0.701, p less than 0.001). Moreover, AVP concentration in random urine was significantly correlated with AVP excretion in 24 hr-urine (r = 0.703, p less than 0.05, n = 9), and this suggested that random UAVP concentration may indicate daily UAVP secretion. In normal subjects, AVP concentration in random urine was widely scattered from 9.2 to 470.6 pg/mg Cr (89.5 +/- 76.4 pg/mg Cr, n = 211). In patients with diabetes insipidus (DI), UAVP concentration (1.6 to 13.0 pg/mg Cr, 6.94 +/- 2.77 pg/mg Cr, n = 25) was significantly lower (p less than 0.001) than that of normal subjects. UAVP concentration in a patient with primary polydipsia (43.2 pg/mg Cr) was not similar to that of ID but to that of normal subjects. UAVP concentration in 2 patients with SIADH was not more than that of normal subjects, indicating that random UAVP concentration is not suitable for detecting inappropriate AVP secretion. In this study, it is suggested that patients of random UAVP concentration below 13.0 pg/mg Cr should be recommended other intensive examination to diagnose DI, even though 2 normal subjects (0.9%) were incorrectly estimated as DI. In conclusion, radioimmunoassay of AVP in unextracted random urine is easy to sample and assay, and useful in screening polyuric patients.

Diabetes Insipidus↗

Involvement of tryptase-related cellular protease(s) in human immunodeficiency virus type 1 infection.

Trypstatin, a new cellular Kunitz-type protease inhibitor purified from rat mast cells, inhibited syncytium formation in human immunodeficiency virus type 1 (HIV-1)-infected CCRF-CEM and uninfected Molt-4 clone 8 at a concentration of 1 microM. Anti-rat tongue mast cell tryptase antibodies reacted with Molt-4 clone 8 cells, as determined by Western blot and by immunofluorescence. In addition, the antibody inhibited syncytium formation. These findings along with homologous sequences with trypstatin and a neutralizing epitope of gp120 of HIV-1 suggest that a tryptase-like cellular enzyme(s) is involved in HIV-1 infection.

Acquired Immunodeficiency Syndrome↗

Profiles of expression of activated cell antigens on peripheral blood and lymph node cells from different clinical stages of adult T-cell leukemia.

The expression of activated cell antigens (Ags) on adult T cell leukemia (ATL) cells at different clinical stages (acute, chronic, and smoldering), and ATL cells from enlarged lymph nodes were studied using monoclonal antibodies (MoAbs). The expressions of CD25 (Tac), CD28, T9 (transferrin receptor), and Ki-67 (proliferating cell nuclear antigen) Ags were high, and that of CD7 Ag was low in both acute and chronic ATL cells compared with that in normal T cells. The expressions of T9 and Ki-67 Ags were higher in acute ATL cells than in chronic ATL cells. The expression of CD38 Ag was higher in acute ATL cells but not in chronic ATL cells compared with normal T cells. On the contrary, the expression of HLA-DR Ag on the cell surface and the transcript of the HLA-DR Ag gene were high in chronic ATL cells, but not in acute ATL cells. A high percentage of lymph node ATL cells expressed T9, CD38, and Ki-67 Ags, although the peripheral blood ATL cells of the same patients showed significantly lower levels of expression of the same Ags. Interestingly, CD7 and HLA-DR Ags were detected on the majority of lymph node ATL cells. Moderately high percentage of smoldering ATL cells expressed CD25, CD28, and HLA-DR Ags, though a few numbers of leukemic cells were present in the samples. These findings confirm that the modes of activation of ATL cells in different clinical stages differ, and suggest that the differences might be reflected in the clinical features. The low expression of HLA-DR Ag in acute ATL cells, despite high expression of the Ag in chronic ATL cells, suggests that successive events that suppress HLA-DR Ag expression are necessary for the transformation of chronic ATL cells into acute ATL cells. Moreover, the high expressions of T9, CD38, Ki-67, CD7, and HLA-DR Ags on lymph node ATL cells indicate that ATL cells preferentially proliferate in lymph nodes.

Antibodies, Monoclonal↗

Homozygous variant of antithrombin III that lacks affinity for heparin, AT III Kumamoto.

Abnormal antithrombin III (AT III) was found in the plasma of a 31-year-old female who suffered from recurrent thrombotic episodes. Heparin cofactor activity was 28% of normal and undetectable when measured by inhibition of thrombin and factor Xa (F.Xa), while both progressive antithrombin and antifactor Xa activities were normal. The concentration of plasma AT III antigen was 37 mg/dl. Analysis by crossed-immunoelectrophoresis (CIE) in the presence of heparin and affinity chromatography on heparin-Sepharose revealed that the propositus' AT III did not bind to heparin. When heparin cofactor II (HC II) was removed from propositus' plasma, heparin cofactor activity of AT III was not detected. Thus, HC II seemed to account for the plasma heparin cofactor activity found in the presence of thrombin. The patient's parents and three of her brothers demonstrated qualitative abnormality of AT III; heparin cofactor activity was 30-50% of normal levels in the presence of both thrombin and F.Xa. These findings indicate that the propositus' AT III lacks affinity for heparin and the mode of its inheritance seems to be autosomal dominant and, hence, the propositus would be a homozygote. For this variant, the name of AT III Kumamoto is proposed.

Adult↗

Characteristic mode of action of gangliosides in selective modulation of CD4 on human T lymphocytes.

We have explored the possible mechanisms for selective modulation by gangliosides of CD4 on human T lymphocytes and subsequent re-expression of CD4. Indirect immunofluorescence staining with anti-CD4 antibodies revealed newly internalized CD4 in ganglioside-treated cells after membrane permeabilization with 0.1% saponin. Cycloheximide and other metabolic inhibitors did not alter the modulation but inhibited significantly the re-expression of CD4. These results suggest both selective modulation of CD4 by a process of endocytosis and re-expression of CD4 through de novo protein synthesis.

Antigens, Differentiation, T-Lymphocyte↗