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Biomedical subjects

T Yasaka

Publications and source records attributed to T Yasaka.

At least 37 records · Page 2Linked to original sources
PubMed1983

Immunopathological characterization of the delayed hypersensitivity skin reaction to carrier protein.

Characteristics of the allergic skin reaction to free carrier protein in sensitized guinea pig with hapten-carrier conjugate have been studied. The animals sensitized with a low dose (4 micrograms) of dinitrophenylated bovine gamma globulin with Freund's complete adjuvant demonstrated a dermatitis when challenged intradermally with a small dose (10 micrograms) of bovine gamma globulin on the 10th or 14th day. The dermatitis was grossly and histologically similar to the classical form of delayed-type hypersensitivity skin reaction except lesser induration and less abundant neutrophil infiltration in the former. This reaction was clearly different from cutaneous basophil hypersensitivity because of the long lasting time course and fewer basophil infiltration in the former. No humoral antibody to carrier protein was detected in the sera of the sensitized animals by passive cutaneous anaphylaxis or by immunodiffusion in agar plates, and the state of the hypersensitivity could be passively transferred with peritoneal exudate cells and spleen cells. These observations indicated that the skin reaction to carrier protein might be of primarily delayed-type hypersensitivity. The vascular permeability change at the reaction sites was observed as a single phase delayed response and preceded the maximum erythema by about ten hours.

Animals↗
PubMed1983

Comparative studies of functional characteristics of mononuclear cell subsets and granulocytes.

Two human peripheral blood monocyte subsets and lymphocytes were isolated by counterflow centrifugal elutriation (CCE). The cell volumes of 303 mu3 and 380 mu3 were measured for the smaller and larger monocyte populations, respectively. Superoxide release by large monocytes exposed to opsonized zymosan was five times more active than that of the small monocytes. The production of colony stimulating activity was two-fold greater and the myeloperoxidase activity was 1.4-fold greater by the larger monocytes. Enriched fractions of cytotoxic cells responsible for natural killer (NK) activity against neuroblastoma cells were also obtained by counterflow centrifugal elutriation. Natural killer cells were obtained in larger lymphocyte fractions and had a mean cell volume of 180 mu3. Compared with the NK activity against the neuroblastoma cells, both the small and large monocytes displayed greater antibody-dependent cellular cytotoxicity (ADCC) activity against human erythrocytes. The larger peripheral blood monocytes aggregated in response to FMLP (N-formyl-methionyl-leucyl-phenyl alanine peptide) and PAF (platelet activating factor). Unlike the granulocyte, monocyte aggregation in response to FMLP was not accompanied by degranulation nor was it potentiated by cytochalasin B. In addition, monocyte aggregation could be blocked by benoxaprofen, unlike the granulocyte. Thus, CCE provides a means of isolating subsets of monocytes and lymphocytes and obtaining large numbers of peripheral blood monocytes for functional studies.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1983

On the calculation of a "reference change" for comparing two consecutive measurements.

We describe a statistical method for calculating a "reference change," defined as that difference between two consecutive test results in an individual that is statistically significant in a given proportion of all similar persons. By allowing for variation in within-person variances, this procedure computes a reference change that is more specific (i.e., less prone to false positives) than that obtained directly from the distribution of observed differences between measurements. Moreover, the method may easily be extended to a test for trend in three successive measurements. The method has been applied to semi-annual measurements of serum calcium and alkaline phosphatase in 698 men and women enrolled in a large health-maintenance program. We believe that these ideas may also be usefully applied to successive laboratory tests in carefully defined patient populations--but this introduces special problems, which are discussed briefly.

Alkaline Phosphatase↗
PubMed1982

Monocyte aggregation and superoxide anion release in response to formyl-methionyl-leucyl-phenylalanine (FMLP) and platelet-activating factor (PAF).

Like the PMN, human peripheral blood monocytes were capable of aggregating in response to FMLP and PAF. Monocyte aggregation was dependent on glycolysis and the presence of divalent cations. Unlike the PMN, monocyte aggregation in response to FMLP was not accompanied by degranulation, nor was it potentiated by cytochalasin B. Furthermore, cytochalasin B and its cogenitor, dihydrocytochalasin B, inhibited aggregation in response to PAF. PAF and FMLP appeared to react with the monocyte at separate receptors because sequential challenge of the monocyte with the same agents failed to elicit further aggregation, whereas rechallenge with the alternative agent induced further aggregation. Because the monocyte will aggregate to chemotactic agents in vitro, it is likely that the cell will be affected by these agents in vivo, which could lead to leukoembolization of circulating monocytes.

Calcium↗
PubMed1982

Comparing multivariate and univariate subject-specific reference regions for blood constituents in healthy persons.

We examined the comparative behavior of subject-specific multivariate and univariate reference regions, using both computer-generated data and serial (semi-annual) measurements of selected analytes in subjects from a large health-maintenance program. Univariate studies under both homeostatic and random-walk time-series models were helpful in defining expected results, but only the homeostatic model was used in multivariate as well as univariate forms. Analysis of the computer-generated data and the real biochemical series produced similar findings, which showed the multivariate subject-specific reference region to be much more conservative than corresponding univariate intervals. That is, a multidimensional point of p correlated observations is quite likely to lie within the individual's multivariate reference region (based on past observation vectors), even when one or more of the observations lie outside their separate reference intervals for that individual. One consequence of this high specificity against univariate false positives in a large surveillance program is a higher than expected proportion of positive multivariate vectors in which none of the values lie outside their univariate ranges. Thus, although the development of multivariate reference regions should be encouraged, they should be used in conjunction with, not instead of, univariate ranges.

Analysis of Variance↗
PubMed1982

Enrichment by counterpart centrifugal elutriation of human lymphocytes cytotoxic to human tumour cells.

The enriched fractions of cytotoxic cells responsible for natural killer (NK) activity against both human sarcoma and neuroblastoma (LA-N2) cell lines were readily obtained by countercurrent centrifugal elutriation (CCE). The NK cells were obtained in the larger lymphocyte fractions (fraction 6 +/- 1), having a mean cell volume of 180 u3. The cytotoxic-enriched fraction contained 51% large lymphocytes having cytoplasmic granules. On the other hand, monocytes were purified to greater than 90% and isolated in another fraction (final fraction) and these cells had the lowest NK activity against both human tumour cell lines. However, compared with the lymphocyte fractions, small and large monocytes displayed greater antibody-dependent cellular cytotoxicity (ADCC) activity against human B erythrocytes. These results indicate that NK found to have activity against both tumour cells lines were larger lymphocytes, not small monocytes. Thus, countercurrent centrifugal elutriation (CCE) can provide a sensitive method to obtain enriched fractions of large lymphocytes contained tumoricidal activity against human sarcoma and neuroblastoma cell lines.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1981

The role of polymorphonuclear leukocytes in delayed hypersensitivity skin reactions: suppressive effects of anti-polymorphonuclear leukocyte serum.

Rabbit antisera (APS) against normal guinea pig peritoneal exudate polymorphonuclear leukocytes (PMN), when injected intraperitoneally three times within 24 h into guinea pigs, lead to a marked fall in the blood PMN count (below 100/mm3) 24-72 h after the injection and a mild depression in the number of circulating mononuclear leukocytes (MNC) at 36-72 h. APS treatment of guinea pigs led to a marked suppression of delayed hypersensitivity skin reactions in response to dinitrophenylated bovine gamma-globulin. The volume, induration, mean diameter of the reaction and leukocyte (both PMN and MNC) emigration into local sites were suppressed, as was, to a lesser extent, vascular permeability. Based on these observations it appears that circulating PMN are required for the full expression of delayed hypersensitivity reaction engendered by bovine gamma-globulin.

Animals↗
PubMed1981

Functions of human monocyte and lymphocyte subsets obtained by countercurrent centrifugal elutriation: differing functional capacities of human monocyte subsets.

Two monocyte subsets from the peripheral blood of healthy humans were isolated by countercurrent centrifugal elutriation (CCE), and their functional heterogeneity was assessed. Cell volume of the smaller monocyte population was (332 +/- 32 mu 3), compared with the larger monocytes (380 +/- 30 mu 3). Superoxide release by large monocytes exposed to opsonized zymosan was 1.5-fold more active than those of small monocytes. Furthermore, the production of colony-stimulating factor (CSF) and myeloperoxidase activity by the larger monocytes was 2-fold and 1.4-fold greater than that of small monocytes, respectively. Thus, CCE provides a useful means to isolate 2 subsets of monocytes with similar functional properties but quantitatively different activities. This suggests that the 2 subsets may be closely related in their developmental spectrum.

Bone Marrow Cells↗
PubMed1981

Acceleration of lipid peroxidation in human paraquat poisoning.

A 20-year-old man ingested approximately 15 to 20 mL of a 24% solution of paraquat. Acute renal and liver failure developed. The patient began undergoing hemodialysis and receiving vitamin E, but he died of pulmonary fibrosis the 27th day after the ingestion. During a two-week period of observation, evidence of lipid peroxidation in his serum was noted by determining malondialdehyde levels. Guinea pigs exposed to paraquat showed similar patterns of malondialdehyde presence in plasma. These results indicate that increased serum or plasma levels of lipid peroxide occurring in paraquat poisoning might reflect production of highly reactive oxygen free radicals and that, possibly, levels of lipid peroxides could serve as indicators of the efficacy of therapy directed toward scavenging free radicals.

Adult↗
PubMed1979

Different effects of concanavalin A and its succinylated derivative on superoxide release in peritoneal macrophages.

The effects of tetravalent conconavalin A and its succinylated derivative on the intracellular production of superoxide anion (O-2) and its release into cell exterior of peritoneal macrophages were observed. Both tetravalent concanavalin A and its succinylated derivative induced marked enhancement of intracellular reduction of nitroblue tetrazolium, which could be inhibited by alpha-methyl-D-glucoside. The extent of activation of nitroblue tetrazolium reduction induced by both types of the lectin paralleled the activation ratio of oxygen consumption. There was little difference in the extent of intracellular O-2 production induced by two types of the lectin. Nitroblue tetrazolium reduction was not affected significantly by pretreatment with colchicine, rotenone or malonate, inhibitors of the cytoskeletal system and of the electron transport system. In contrast, tetravalent concanavalin A induced a higher rate of superoxide release than did succinylated divalent concanavalin A, which lacks the cross-linking activity of surface glycoproteins. These results indicate that superoxide production following oxygen consumption and superoxide release into cell exterior are controlled independently by a separate membrane mechanism and that superoxide production system is not essentially dependent on the involvement of the cytoskeletal system.

Animals↗
PubMed1978

Effect of concanavalin A and its succinylated derivative on the oxidative metabolism of guinea pig peritoneal macrophages.

The effect of concanavalin A and its succinylated derivative on the metabolic regulation of guinea pig peritoneal macrophages was observed. The binding of tetravalent concanavalin A to the surface glycoproteins of macrophages caused a marked increase in the rate of oxygen consumption due to the activation of the hexose monophosphate shunt. Divalent succinylated concanavalin A, also induced a similar change in the rate of oxygen metabolism. The metabolic change induced by these two types of lectin was reversibly inhibited by alpha-methyl-D-glucoside, a haptenic inhibitor of these lectins, and was temperature dependent (observed at above 15 degrees C). It is suggested that the binding of these lectins to the surface glycoproteins, and not their cross-linking into caps, is required for the activation of oxygen metabolism of macrophages, and that highly fluid state of the plasma membrane seems to be an essential requirement for the transduction of glycoprotein perturbation on the macrophage surface into cellular interior via transmembrane control mechanism.

Animals↗
PubMed1978

Clinical data evaluation and the PL health control information system.

In a health control service environment, that is, a periodic, membership AMHTS type of comprehensive health check-up system, where clinical data evaluation especially an evaluation in terms of subject-specific normal ranges, is most important, the medical information system is required to handle: (1) Various network types files; (2) real-time immediacy; (3) an asserted reliability to meet personal health control purposes. As in other computer applications already successfully used, an indexed direct assess method (IDAM) developed is our solution. It allows us to provide multiple indices for the file network, instead of inverted files, a unique index-to-record relationship, preventing any unrecoverable chaining destruction and, thereby, provides any network type access a stable access time. Furthermore, for research purposes, a data integrity for on-line access and batch access was attained as well as a retrieval language system with a multiple key retrieval function.

Diagnosis, Computer-Assisted↗
PubMed1978

A family of Gardner's syndrome with report of an autopsy case.

A family with Gardner's syndrome including one autopsy case is reported. A 22 year-old man had multiple polyposis of the colon and the small intestine, epidermal cysts, soft part tumor of the abdominal skin and osteomas in the calvarium and rib, and died of a carcinoma in the transverse colon and embolism of the brain. Histologically, all polyps were diagnosed as adenomatous polyp. The greater their diameter, the higher the tendency of atypism was observed. However, the polyps around the cancer were few, small, and with low atypism, and we could not obtain evidence showing direct transformation of adenomatous polyps into carcinoma. His two elder brothers had multiple polyposis of the colon, epidermal cysts and osteomas in the calvarium or mandibular bone, but are still alive.

Adult↗