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Biomedical subjects

T Kambara

Publications and source records attributed to T Kambara.

At least 127 records · Page 7Linked to original sources
PubMed1986

Hageman factor dependent pathway in local vascular permeability enhancement.

The possibility of an involvement of the kallikrein-kinin system in increasing vascular permeability induced by intradermal injection of the guinea pig activated Hageman factor (beta HFa) was examined. In vitro system, the kinin generation was observed in guinea pig plasma when the plasma was incubated with beta HFa. This kinin generation was dependent upon the dose of beta HFa added and upon the presence of plasma prekallikrein, since 97 percent of the kinin release was diminished by removing the prekallikrein in plasma by treatment with anti-prekallikrein antibody. These results suggested that the Hageman factor-kallikrein-kinin cascade in guinea pig was similar to those in human and bovine plasma. In the permeability experiment in vivo, a simultaneous injection of soybean trypsin inhibitor (10(-6) M), which is the inhibitor of guinea pig plasma kallikrein, inhibited the permeability response to beta HFa by more than 90 percent. The permeability response to beta HFa was attenuated 5 fold in animals depleted of the circulating plasma prekallikrein by intraarterial antibody administration. These results indicated the participation of plasma prekallikrein in the permeability reaction to beta HFa. A simultaneous injection of a kinin destructive enzyme, carboxypeptidase B, diminished the permeability reaction to beta HFa, without any inhibition of the amidolytic activity of beta HFa or plasma kallikrein. A simultaneous injection of an inhibitor of a kinin destructive enzyme (kininase II), SQ 20,881(Glu-Tyr-Pro-Arg-Pro-Gln-Ile-Pro-Pro-OH), augmented the permeability reaction to beta HFa 10 fold, without any effect on the amidolytic activity of beta HFa or plasma kallikrein.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Immunohistochemical studies on synthesis and distribution of Hageman factor and kininogen.

Immunohistochemical localization of Hageman factor and high molecular weight kininogen were investigated in liver, skin and kidney of guinea pig using a new conjugation method with maleimide derivative as the coupling reagent at the level of light and electron microscopes. In the liver, the positive reactions of both factors were observed in the rough and smooth endoplasmic reticulums and the Golgi apparatus in hepatocytes. In Kupffer cells and sinusoidal endothelial cells, the reaction products were visible only in the endocytotic vesicles. These findings suggested that guinea pig Hageman factor and high molecular weight kininogen were synthesized only in hepatocytes at least the liver. In the skin, positive reactions were seen in the intercellular space of epidermis, and along the basement membranes of epidermis and vessels, and among the collagen fibers in interstitial tissue particularly in papillary dermis. This interstitial presence of these molecules was also seen in liver and kidney, which suggested that Hageman factor and high molecular weight kininogen were widely distributed in the interstitial tissue space even under normal conditions. In addition, positive reactions were obtained in the reabsorption vesicles and the lysosomes of the proximal convoluted tubules of kidney and in the pinocytotic vesicles of the basal cells of epidermis. According to these findings, it was suggested that both factors were produced in hepatocytes, secreted into the blood stream, distributed in the interstitial tissue by vascular permeability even under normal condition, and reabsorbed and catabolized in the kidney and the skin.

Animals↗
PubMed1986

Failure of guinea pig plasma kallikrein to cause neutrophil migration.

Guinea pig plasma kallikrein was apparently chemotactic for guinea pig neutrophils when assayed in Boyden's chamber. However, it was concluded that this phenomenon was artificial due to the following reasons: Kallikrein was only chemotactic in the presence of bovine serum albumin (BSA) in the chamber but not when BSA was substituted by guinea pig serum albumin or egg albumin. Kallikrein injection failed to cause dermal tissue leukocytosis. Kallikrein did not polarize neutrophils. A chemoattractant(s) seemed to be generated from BSA preparation time dependently. Although this generation required the enzymatic activity of kallikrein, the chemotactic activity once generated was resistant to a kallikrein inhibitor (diisopropylfluorophosphate) and antiprekallikrein antibody.

Animals↗
PubMed1986

Inflammatory activity of a trypsin-like protease in the tuberculin reaction sites in guinea pig skin.

A trypsin-like protease(s) was found in the extracts from tuberculin reaction sites in the guinea pig skin. Extractable enzyme activities were chronologically paralleled with the gross appearance of the inflammation, and the maximum activity from 24-hour old inflamed sites was about 12 times stronger than that from control skin, suggesting a potential role in the pathogenesis of the delayed hypersensitivity reaction (DHR). The enzyme suitably hydrolyzed t-butyloxycarbonyl-phenylalanyl-seryl-arginine 4-methylcoumaryl-7-amide, and was partially purified by gel filtration. It showed an apparent molecular weight of 700,000 with optimal pH of 9.0-9.5. The activity was inhibited by various serine protease inhibitors but not by thiol or metal protease inhibitors. It was relatively heat-stable. These findings suggest that the protease is similar to a trypsin-like protease from DHR to bovine gamma-globulin. Intradermal injection of the enzyme into normal guinea pigs induced a mixed neutrophil-mononuclear infiltrate. The reaction was reduced in intensity with the diisopropylfluorophosphate-inhibited enzyme preparation. The enzyme did not induce any increased vascular permeability. These findings suggest that the protease may be present generally in the DHR sites and probably participates in the cellular response of DHR.

Animals↗
PubMed1986

Pseudomembranous colitis in a patient of paraquat intoxication.

A 49 year-old man drank paraquat 7-8 fold of human fatal dose, and died of severe respiratory failure in 24 days in spite of intensive therapy. The autopsy revealed diffuse pulmonary fibrosis caused by prolonged intoxication of paraquat. An interesting finding was many raised plaques from 1 mm to 10 mm in diameter, observed in whole colon. Histologically, these plaques were composed of necrotic mucosa ("pseudomembrane"), disrupted crypts and edematous submucosa with fibrin education, intervening in normal colon tissue with sharp margins, and diagnosed as non-antibiotic-induced pseudomembranous colitis. Since the edematous submucosa of the raised plaque had a stratified fibrin education around a dilated capillary, it was speculated that the vessel injury by paraquat might play a role in the pathogenesis of pseudomembranous colitis.

Administration, Oral↗
PubMed1986

Chemotactic activity for polymorphonuclear and mononuclear leukocytes in rheumatoid synovial fluids.

In order to why polymorphonuclear leukocytes (PMNs) are predominant and mononuclear leukocytes (MNLs) are few in rheumatoid synovial fluids, chemotactic factor(s) for PMNs and MNLs were studied in the synovial fluids of rheumatoid arthritis (RA-SF) and osteoarthritis (OA-SF) using both Boyden's and agarose methods. The RA-SF showed strong chemotactic activity for human peripheral blood PMNs compared with non-rheumatoid OA-SF. The chemotactic activity for PMNs was well correlated with the number of PMNs in RA-SF, suggesting that it was a natural mediator for PMN emigration into rheumatoid joint cavity. The major chemotactic factor for PMN in RA-SF was of apparent molecular weight of 14,000 and its activity was suppressed to less than 10 percent by anti-C5a antibody, but it failed to show any anaphylatoxin activity which was an attribute of C5a. It was, therefore, suggested to be C5a-like molecule but not C5a itself. The possibility that the factor may be a C5a des-Arg was discussed. On the contrary, the chemotactic activity for MNLs was not found neither in RA-SF nor OA-SF. These findings may explain the fact that PMNs are predominant in rheumatoid synovial fluids.

Arthritis, Rheumatoid↗
PubMed1985

Molecular mechanism of water oxidation in photosynthesis based on the functioning of manganese in two different environments.

We present a model of photosynthetic water oxidation that utilizes the property of higher-valent Mn ions in two different environments and the characteristic function of redox-active ligands to explain all known aspects of electron transfer from H(2)O to Z, the electron donor to P680, the photosystem II reaction center chlorophyll a. There are two major features of this model. (i) The four functional Mn atoms are divided into two groups of two Mn each: [Mn] complexes in a hydrophobic cavity in the intrinsic 34-kDa protein; and (Mn) complexes on the hydrophilic surface of the extrinsic 33-kDa protein. The oxidation of H(2)O is carried out by two [Mn] complexes, and the protons are transferred from a [Mn] complex to a (Mn) complex along the hydrogen bond between their respective ligand H(2)O molecules. (ii) Each of the two [Mn] ions binds one redox-active ligand (RAL), such as a quinone (alternatively, an aromatic amino acid residue). Electron transfer occurs from the reduced RAL to the oxidized Z. When the experimental data concerning atomic structure of the water-oxidizing center (WOC), electron transfer between the WOC and Z, the electronic structure of the WOC, the proton-release pattern, and the effect of Cl(-) are compared with the predictions of the model, satisfactory qualitative and, in many instances, quantitative agreements are obtained. In particular, this model clarifies the origin of the observed absorption-difference spectra, which have the same pattern in all S-state transitions, and of the effect of Cl(-)-depletion on the S states.

Journal Article↗
PubMed1985

Application of a new method of antibody-enzyme conjugation with maleimide derivative for immunohistochemistry: hepatocellular production, interstitial tissue distribution, and renal cell reabsorption of plasma albumin in guinea pig.

A new sophisticated method for enzyme-antibody conjugation developed in quantitative solid-phase enzyme immunoassay was revealed to be an applicable method for immunohistochemistry; one that offered several advantages over present methods. Using a new maleimide derivative as a coupling reagent, monomeric conjugate of horseradish peroxidase and Fab' antibody was easily prepared with high efficiency and reproducibility. Nonspecific staining was greatly reduced in the presence of this monomeric conjugate. Since the enzyme activity and antigen-binding activity were well preserved in the conjugate, the reaction was strong enough to analyze the antigen localization in intracellular organelles or in interstitial tissue space by both light and electron microscopy. The fate of plasma albumin was investigated in liver, skin, and kidney using the new method with rabbit anti-guinea pig albumin antibody, and satisfactory results were obtained. In the liver, the reaction products were observed in the rough and smooth endoplasmic reticulum and the Golgi apparatus in hepatocytes, which confirmed the synthesis of plasma albumin in hepatocytes of guinea pig. In a study of the distribution of albumin, reaction products were seen in the intercellular space of the epidermis, along the basement membranes of epidermis and of proximal convoluted tubules in kidney, and among the collagen fibers in interstitial tissue, particularly at papillary dermis, suggesting the wide distribution of plasma albumin in interstitial extravascular tissue spaces. In addition, positive reaction was obtained in the apical vesicles and the lysosomes of the proximal convoluted tubules and in the pinocytotic vesicles of the basal cells of epidermis, suggesting the reabsorption and destruction of albumin in the kidney and the skin.

Animals↗
PubMed1984

A self-consistent chain model for the phase transitions in lipid bilayer membranes.

We presented a mechanical model of a lipid bilayer membrane. The internal conformations of a polar head group and double hydrocarbon chains in a lipid molecule were described on the basis of the isomeric bond-rotation scheme. The thermodynamic properties of the lipid membranes were represented by a density matrix that described the rotational isomeric states of the head groups and chains. The parameters that determined the density matrix were obtained in the presence of the intermolecular interactions, which depend on the conformation of the molecules. The interchain interaction was given by the Kihara potential, which depends on the shape of the chains. The Coulomb interaction between the polar head groups and the lateral pressure were considered. The calculation was made for the three lipid molecules corresponding to DMPC, DPPC, and DSPC. The model agreed well with the following experimental results: the temperature, the latent heat of the gel-to-liquid crystalline phase transition, the temperature dependencies of (a) the intermolecular distance, (b) the number of gauche bonds in a hydrocarbon chain, (c) the order parameter for the bond orientation, (d) the volume of the membrane, (e) the thermal expansion coefficients, and (f) the birefringence.

Birefringence↗
PubMed1984

A high-molecular-weight trypsinlike protease in the skin sites of delayed hypersensitivity in guinea pigs.

A trypsinlike protease was extracted from the delayed hypersensitivity skin sites in guinea pigs. Extractable amounts of the enzyme were chronologically paralleled with the gross appearance of the inflammation, and the maximum activity from the inflamed sites at 24-36 hours was about 20 times stronger than that from normal skin, suggesting a potential role in the pathogenesis of the delayed hypersensitivity reaction. The enzyme, which suitably hydrolyzed t-butyloxycarbonyl-phenylalanyl-seryl-arginine 4-methylcoumaryl-7-amide, was partially purified by isoelectric focusing or by gel filtration. The enzyme demonstrated a single peak of activity on the former column with an apparent isoelectric point of 4.2, and in the latter it showed an apparent molecular weight of 600,000 (600K-protease). When incubated with 3H-diisopropylfluorophosphate, the enzyme lost all amidolytic activity and yielded a single band of radioactivity in polyacrylamide disk gel electrophoresis in the presence of sodium dodecyl sulfate, and a single peak of radioactivity in gel filtration, both having an apparent molecular weight of 31,000-33,000 (31K-protease). That the 600K-protease might be a complex with alpha 2-macroglobulin was ruled out. The 31K-protease was separated from the 600K-protease by gel filtration in the presence of 6 M guanidine hydrochloride, and was renatured to an active form. An apparent isoelectric point of the 31K-protease observed was 9.4, suggesting that the 600K-protease may be a complex of 31K-protease with an acidic carrier molecule(s). Both proteases, 31K- and 600K-protease, had identical substrate specificity, a pH profile of amidolytic activity, and susceptibility to exogenous protease inhibitors. However, when sensitivities to intrinsic protease inhibitors in guinea pig plasma, two kinds of trypsin inhibitor, and alpha 2-macroglobulin were compared, the 600K-protease was at least 100 times more resistant than the 31K-protease. It was supposed that one of the pathophysiologically significant functions of the complex formation might be to maintain the enzyme activity longer in vivo.

Amidohydrolases↗
PubMed1984

Guinea pig macroalbumin. A major inhibitor of activated Hageman factor in plasma with an alpha 2-macroglobulin-like nature.

A major inhibitor of the beta form of activated Hageman factor (beta-HFa) with an apparent molecular weight of 28,000, which was reported as a strong permeability factor (Yamamoto and Cochrane, Am J Pathol 1981, 105: 164-175), was purified from guinea pig plasma. When it was depleted in vitro, the plasma lost 71% of the total inhibitory activity toward beta-HFa. The inhibitor, termed "macroalbumin," with an apparent molecular weight of 720,000 and an apparent pI of 4.6, seemed to be an inhibitor similar to alpha 1- or alpha 2-macroglobulin of man and other mammalian species in physicochemical characteristics and in enzymologic properties. Though the inhibitory activity to beta-HFa was negligible in normal skin extract, a significant inhibitory activity appeared in extracts of permeability-enhanced skin sites which were induced by intradermal beta-HFa injection. The inhibitory activity that appeared was macroalbumin-dependent, with more than a 10-fold increase in the concentration. These results indicate the roles of macroalbumin as a negative feedback regulator in situ to the Hageman-factor-dependent pathway in a permeability enhancement system.

Animals↗
PubMed1984

The chemical mediation of delayed hypersensitivity skin reactions. IV. Activation of chemotactic factor precursor by a trypsin-like protease in guinea pig plasma.

A single-chain precursor protein for macrophage chemotactic factor was previously reported (Ueda et al, Am J Pathol, 1982, 108:291-298). Apparent chemotactic activity was spontaneously generated in the precursor fraction during a long period of incubation, correlating with the cleavage of the precursor molecule into a two-chain protein. Generation and the limited proteolysis were both inhibited by phenylmethylsulfonyl fluoride (PMSF), a serine protease inhibitor, suggesting the presence and the role of a serine protease in the fraction. A serine protease was actually activated and separated from the precursor fraction with a benzamidine-conjugated cellulose affinity column. The protease was heat-labile, and the substantial molecular weight was 20,000 by gel filtration on a Sephadex G-75 column and 23,000 by SDS-polyacrylamide gel electrophoresis. It hydrolyzed [3H-acetyl casein and also fluorogenic synthetic substrates, butyloxycarbonylphenylalanylserylarginine methylcoumarylamide and butyloxycarbonylisoleucylglutamylglycylarginine methylcuomarylamide, and was inhibited by diisopropylfluorophosphate, PMSF, trasylol, soybean trypsin inhibitor, and tosyllysine chloromethylketone, but not by tosylphenylalanine chloromethylketone, chymostatin, p-chloromercuricbenzoate or ethylenediaminetetraacetate. By incubation of the precursor with the protease, rapid generation of chemotactic activity for macrophages was observed. The fact that the chemotactic factor newly generated in vitro was identical with a macrophage chemotactic factor previously separated from extract of delayed type hypersensitivity skin sites immunologically and physicochemically suggested an essential role of the protease in macrophage chemotactic factor generation in the delayed hypersensitivity skin reaction.

Animals↗
PubMed1984

Guinea pig plasma kallikrein as a vascular permeability enhancement factor. Its dependence on kinin generation and regulation mechanisms in vivo.

Plasma kallikrein (mol wt 80,000) was purified from guinea pig plasma, and it caused vascular permeability enhancement when injected into guinea pig skin. The activity had a linear relationship to the logarithm of kallikrein concentrations from 5 X 10(-9) M to 5 X 10(-6) M and was blocked by immunopurified anti-prekallikrein F(ab')2 rabbit antibody and soybean trypsin inhibitor. Carboxypeptidase B(1.7 units), a kinin-destructive enzyme, decreased the permeability activity to 1/20, while SQ 20,881 (10(-6) M), an inhibitor to a kinin-destructive enzyme, augmented the activity 5.4-fold. These results suggested that the permeability activity of kallikrein was performed finally through kinin generation in the skin. The permeability activity was short-lasting, and was completely blocked by a kallikrein inhibitor purified from guinea pig plasma, suggesting the presence of a down-regulation system for the permeability activity in vivo. Prostaglandin E2 (25 ng), a hyperemia inducer in microcirculation, augmented the permeability activity 12-fold, suggesting the presence of an up-regulation system in vivo. Accordingly, it was assumed that kallikrein-kinin system might play a role as a vascular permeability enhancement system in guinea pig skin.

Animals↗
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↗
PubMed1982

An alkaline proteinase which has inflammatory activity isolated from guinea pig lymphoid cells.

A phosphate buffer extract of regional lymph node cells (more than 90% lymphocytes) of guinea pigs immunized with bovine immunoglobulin G contained acid and alkaline proteinase activities. The immunized cells contained approximately twice as much proteinase activities than the normal cells. The alkaline proteinase was purified and two forms could be separated. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that one form labeled with [3H]diisopropylfluorophosphate was localized at Mr 28,000 in a single peak in the presence and absence of reducing agent. The enzyme was inhibited by diisopropylfluorophosphate, p-chloromercuribenzoate, N-ethylmaleimide and iodoacetic acid, and was also partially inhibited by phenylmethylsulfonyl fluoride. It was relatively heat-stable. Intradermal injection of the purified form into normal guinea pigs induced a mixed neutrophil-mononuclear infiltrate. The immune reaction was reduced in intensity with the diisopropylfluorophosphate-inhibited enzyme. These findings suggest that the proteinase probably participates in the inflammatory response of cellular hypersensitivity.

Animals↗