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1.
Antibody in sera from pigs carrying an abscess associated with Corynebacterium pyogenes and healthy pigs was examined by the agar gel diffusion test. In the test, the concentrated culture fluid containing the protease of C. pyogenes was used as antigen. As a result, precipitating antibody was demonstrated in sera from 25 of 30 abscessed pigs and a few of the healthy pigs. When the relationship between precipitating antibody and protease was examined by the immunoelectrophoresis and gel filtration of the concentrated culture fluid, the antibody was shown in the same position as the protease. From the result, it was clear that the precipitating antibody was against the protease of C. pyogenes. All the proteases produced by 27 strains of C. pyogenes of porcine and bovine origin were serologically identical with one another. They were, however, serologically different from those of Staphylococcus aureus, Bacillus cereus, and B. subtilis. In the inhibition test, the proteolytic activity of C. pyogenes was inhibited by the serum of the abscessed pig. It was also inhibited by healthy pig serum. From the results, it seems that the determination of precipitating antibody may be useful for the diagnosis of C. pyogenes infection.  相似文献   

2.
In a previous study the authors reported the characterization of some facultatively anaerobic, Gram-positive, non-sporeforming rods which were found in mixed cultures from various infectious processes, including patients with otitis, empyema, perianal abscesses and decubitus ulcers. Phenotypically these organisms closely resembled Actinomyces pyogenes although their precise taxonomic position remained unknown. In the present investigation the authors have determined the 16S rRNA gene sequences of some representative strains of the Actinomyces pyogenes -like bacteria and report the results of a comparative sequence analysis. On the basis of the results of the present and earlier findings two new Actinomyces species, Actinomyces radingae sp. nov. and Actinomyces turicensis sp. nov. are proposed. The type strains are DSM 9169T and DSM 9168T, respectively.  相似文献   

3.
Adsorption of 125I-labeled polyoma virions and capsids to the surface of mouse kidney cells (MKC) and guinea pig erythrocytes was examined. Purified polyoma capsids lack the ability to compete with polyoma virions for specific binding sites on the surface of MKC. These same capsids were, however, able to block virion adsorption to guinea pig erythrocytes. UV-inactivated virions blocked cellular receptors on MKC and thus inhibited infectious virions from infecting the cells. Capsids were unable to inhibit virion infection of MKC. Adsorption of polyoma virions to MKC and infection of these cells were found to be independent of the ability of the virions to agglutinate guinea pig erythrocytes.  相似文献   

4.
The concept of an anti-oxidant defence system as a means to prevent oxidative cell damage implies balanced activities of anti-oxidant defence enzymes. As well as positive correlations between anti-oxidant enzyme activities in human erythrocytes, it has been observed that sometimes when glutathione peroxidase activity is increased, CuZn-superoxide dismutase activity is decreased. In our current study we have examined the plasma lipid profile and the anti-oxidant defence enzymes in erythrocytes from humans, pigs, and bulls. We found that a negative correlation existed between CuZn-superoxide dismutase and glutathione peroxidase activities in human erythrocytes when the concentrations of both plasma triglycerides and total cholesterol were high. This correlation was also found in pig erythrocytes, but not in bull erythrocytes. We propose that cholesterol could affect membrane lipid peroxidation and superoxide generation in erythrocytes via the recently found fraction of cholesterol bound to haemoglobin, termed haemoglobin-cholesterol.  相似文献   

5.
One of the important factors contributing to the pathogenicity of bacteria is the presence of adhesins on cell surface, which facilitate colonisation in the macroorganism. The presence and type of adhesins occurring in four species of the genus Acinetobacter: A. baumannii (184), A. junii (59), A. lwoffii (65) and A. haemolyticus (22) was determined by haemagglutination test with a 3% suspension of fresh, tannic acid-treated of guinea pig, cow and human group O and AB erythrocytes, with or without the addition of one of sugar inhibitors (D-mannose, alpha-methylmannopyranoside, D-galactose-N-acetyl-D-glucosamine, L-fucose and D-ribose). In strains from all species, adhesines of the mannose-resistant (MR) type dominated. The mannose-sensitive (MS) type was present solely on the surface of one A. lwoffii strains. A. baumannii (36), A. junii (8), A. lwoffii (11) and A. haemolyticus (4) exhibited mannose-resistant hemagglutination in relation to fresh erythrocytes and that reaction was restrained by D-galactose, D-galactose and L-fucose (no other inhibitor used restrained it). The results achieved prove that cell adhesines other than those of MR type must be present on the cell surface. Additional adhesines occurred mainly in strains isolated from the respiratory and urinary tract infection simples, but were not found in isolates from blood cultures.  相似文献   

6.
Species-specific distribution of cathepsin E in mammalian blood cells   总被引:1,自引:0,他引:1  
The distribution of cathepsins D and E in leukocytes and erythrocyte ghosts of several mammalian species, and in HL-60 and K-562 cells was examined by means of a combined application of electrophoretic and immunochemical methods. Cathepsin D was found in leukocytes of all species examined, but the distribution of cathepsin E was found to be species-specific: pigs, cows and goats had no cathepsin E activity in leukocytes or erythrocytes at all. In humans, cathepsin E occurred in erythrocytes but not in leukocytes, which contrasted with the guinea pig pattern of its presence in leukocytes and its absence in erythrocytes. No cathepsin E-related enzymes were found in HL-60 or K-562 cells, but these human leukemic cells contained cathepsin D-related enzyme forms that are electrophoretically distinct from normal leukocyte cathepsin D. The present results are inconsistent with the view that cathepsin E may be involved as an essential factor in the biological functions of leukocytes or erythrocytes.  相似文献   

7.
Erythrocytes from the Yucatan miniature pig, like those from the normal domestic pig, lack functional glucose transporters and were unable to utilize plasma glucose as an energy source. In contrast, inosine and adenosine entered the cells rapidly. The nucleoside transporter responsible for this uptake was identified as a band 4.5 polypeptide (5000 copies per cell; apparent Mr 45 000-66 000). Inosine concentrations in the physiological plasma range (1.6-2.5 microM) were found to maintain normal erythrocyte ATP levels and ATP/ADP ratios during prolonged in vitro incubation of cells at 37 degrees C, an effect that was blocked by the specific nucleoside transport inhibitor, nitrobenzylthioguanosine. In the absence of extracellular nucleoside, cells 'protected' themselves against some of the consequences of deprivation of energy substrate by glycolyzing the ribose moiety of inosine produced during ATP catabolism. Although erythrocytes from the miniature pig were capable of utilizing extracellular adenosine as an energy substrate, plasma samples from these animals contained less than 0.4 microM adenosine. It is concluded that inosine is a major physiological energy source of pig erythrocytes.  相似文献   

8.
Kinetic and regulatory properties of the plasma membrane Ca(2+)-ATPase activity from chicken (nucleated) erythrocytes were studied and compared to those from pig (anucleated) erythrocytes. In the absence of known activators: (1) Ca(2+) affinity for the Ca(2+)-ATPase activity from nucleated erythrocytes was 12-fold higher than that from pig erythrocytes, and thus the enzyme is sensitive to physiological Ca(2+) concentrations; (2) the enzyme from chicken erythrocytes showed two apparent Km values for ATP, as compared to one apparent Km value displayed by pig erythrocytes; (3) Ca(2+)-ATPase inserted in chicken erythrocyte membranes showed a low sensitivity to activation by phosphatidylinositol-4-phosphate; (4) when p-NPP was used as substrate, the activity of chicken erythrocytes was high, similar to that attained by pig erythrocytes, but barely sensitive to activation by dimethylsulfoxide and calmodulin. ATP hydrolysis was 10-fold lower than that displayed by pig erythrocytes and the maximal velocity was activated three-fold by calmodulin. The enzyme was insensitive to alkaline phosphatase treatment and showed a single phosphorylation band in electrophoresis, ruling out the possibility of previous modulation by endogenous kinases and/or by partial proteolysis. The differences may be attributed to some endogenous modulator, to distinct isoforms, or to a difference in the E(1)/E(2) states of the enzyme.  相似文献   

9.
Brief shift of purified C5 and C6 at 0 degrees C to pH 6.4, followed by immediate neutralization, results in the generation of a factor, designated C(56)a, that lyses erythrocytes together with C7, C8, and C9. We compared C(56)a and C5b6 generated by an alternative-pathway convertase, with regard to their action on different target cells. We found tht C(56)a is similar to C5b6 in the following properties: 1) Together with C7, C(56)a forms a stable intermediate on either sheep or guinea pig erythrocytes. 2) Membrane-bound C3b, or A2C incorporated in the membrane, enhances lysis by C(56)a-9, as well as lysis by C5b6-9. We also found that the lysis of EC(56)a7 or EC5b67 intermediates by C8 and C9 depends on the species of the erythrocytes and the species of C8 and C9. Thus, lysis of sheep erythrocytes is more efficient with guinea pig C8 and C9 than with human C8 and C9. In the case of guinea pig erythrocytes, this relationship is reversed, i.e., these cells lyse more efficiently when human C8 and C9 are used. Enhancement of lysis by membrane-bound C3b or A2C does not abrogate this species incompatibility pattern.  相似文献   

10.
It is known that a medium conditioned by erythrocytes (ECM) reduces 59Fe uptake into haem in hemopoietic cell cultures. In order to evaluate if the release of this factor in conditioned media is correlated with the whole erythrocyte surface, the same volume of packed erythrocytes of Mammals characterized by different MCV were incubated according to the method of Cole and Regan (1977). The influence of these conditioned media upon 59Fe uptake into haem in cultures of Guinea pig bone marrow cells was studied. Our results demonstrate that ECM of lamb erythrocytes (MCV = 28) caused a more marked depression of haem synthesis in vitro than ECM of calf (MCV = 34) and Guinea pig (MCV = 69) erythrocytes, and that this inhibitory effect is correlated to the MCV of considered erythrocytes.  相似文献   

11.
Mouse, rat, rabbit, hamster, cow, pig, sheep, guinea-pig, dog and human erythrocytes were studied. A 0.9% or stronger solution of sodium chloride completely prevented haemolysis; sheep and pig erythrocytes appeared the more fragile, while human and dog erythrocytes were not haemolized in concentrations of 0.4% or more. Haemolysis of human, rabbit, cow, hamster, guineapig, pig and sheep erythrocytes was not observed in solutions of 0.4% or more of glucose. Except for sheep, human and dog erythrocytes, haemolysis was depressed in rate but not completely prevented by phosphate-buffer solution of pH 7.0.  相似文献   

12.
Antibodies against purified Ca2+-transport ATPase from human erythrocytes were raised in rabbits. Immunodiffusion experiments revealed that precipitating antibodies had been developed. The immunoglobulin fraction inhibited solely the calmodulin-dependent fraction of erythrocyte Ca2+-transport ATPase activity, whereas the basal (in the absence of added calmodulin) activity of the enzyme was not significantly affected by the antibodies. The antibodies produced similar doseresponse curves for the calmodulin- and the oleic acid-stimulated enzyme. However, the immunoglobulin fraction was considerably less effective in inhibiting Ca2+-transport ATPase activated by limited proteolysis. The results obtained with our antibodies are compatible with the interpretation that at least one subpopulation of the antibodies attacks the enzyme at or close to the calmodulin-binding site of the ATPase. The antibodies also inhibited the calmodulin-regulated Ca2+-transport ATPase from pig smooth-muscle plasma membrane, though with lower potency. However, the immunoglobulin fraction failed to suppress pig cardiac sarcoplasmicreticulum Ca2+-transport ATPase activity in the concentration range investigated. In addition, the activity of phosphodiesterase from rat brain, another enzyme modulated by calmodulin, was not at all affected by the immunoglobulin fraction.  相似文献   

13.
The effect of extracellular NADH on the rate of reduction of nitrite-induced methaemoglobin in erythrocytes from man, cattle, dog, horse, grey kangaroo, pig and sheep was investigated. Extracellular NADH was found to enhance the rate of methaemoglobin reduction in man, dog, pig and kangaroo erythrocytes, but had essentially no effect on the rate of methaemoglobin reduction in erythrocytes from cattle, horse and sheep. In erythrocytes of those animals affected by extracellular NADH the rate of reduction of metHb in the presence of NADH was the same or greater than that observed in the presence of nutrients such as glucose and inosine. The combination of nutrient and NADH produced a more profound increase in the rate of methaemoglobin reduction. The rate of methaemoglobin reduction in all cases was significantly less than that observed with methylene blue, the standard treatment of methaemoglobinaemia. Extracellular NADH was found to indirectly increase the intracellular NADH concentration through displacement of the pseudo-equilibrium of the intracellular LDH reaction and relied upon the presence of sufficient LDH activity released into the extracellular medium through haemolysis. The lack of response of cattle, horse and sheep RBCs to extracellular NADH was found to derive mainly from their low extracellular LDH activity, but also correlated with their lower NADH-methaemoglobin reductase activity compared to the other species.  相似文献   

14.
Untreated rabbit erythrocytes adhere to thymus-dependent areas of guinea pig lymphatic tissues as shown with frozen sections. The adherence reaction is temperature dependent. Optimal results were obtained by incubation of the tissue section with the erythrocytes at temperatures between 0 ° and 4 °C. At 37 °C no adherence of erythrocytes was observed. Out of other erythrocytes tested (human, sheep, chicken, rat, mouse) only rat and mouse cells showed weak adherence to guinea pig thymus sections.  相似文献   

15.
16.
Three monoclonal antibodies have been raised against partially purified band 4.5 polypeptides [Steck (1974) J. Cell Biol. 62, 1-19] from pig erythrocyte membranes. The antibodies were capable of binding to both intact pig erythrocytes and protein-depleted membrane preparations and recognized detergent-solubilized polypeptides from adult and neonatal pig erythrocytes that were photolabelled with [G-3H]nitrobenzylthioinosine (NBMPR), a potent specific inhibitor of nucleoside transport. The antibodies did not recognize polypeptides from neonatal pig erythrocytes that were photolabelled with the glucose-transport inhibitor [3H]cytochalasin B. Reactivity with polypeptides of apparent Mr 64,000 [10% (w/v) acrylamide gels] was demonstrated by Western-blot analysis. The antibodies recognized pig band 4.5 polypeptides after prolonged treatment with endoglycosidase F, a finding consistent with reactivity against polypeptide, rather than carbohydrate, determinants. Trypsin digestion of NBMPR-labelled protein-depleted pig erythrocyte membranes generated two labelled polypeptide fragments (Mr 43,000 and 26,000). Two of the antibodies recognized both fragments on Western blots, whereas the third bound to the larger, but not to the smaller, fragment. The antibodies had no significant effect on reversible binding of NBMPR to protein-depleted pig erythrocyte membranes and did not bind to NBMPR-labelled polypeptides in human, rabbit or mouse erythrocytes.  相似文献   

17.
A cell line sensitive enough for the recovery of all parainfluenza viruses and free of simian virus contamination frequently occurring in monkey kidney cells was sought. The VERO cell obtained from African monkey kidney was found suitable for the initial isolation of types 1, 2 and 3 parainfluenza viruses, although the cells did not always allow the successive transfer. Mixed cultures of VERO and HEp-2 cells were also useful in the recovery of various respiratory viruses including parainfluenza viruses. The characteristics of hemagglutinins of parainfluenza viruses were examined, and type 2 parainfluenza and SV5 viruses agglutinated both guinea pig and green monkey erythrocytes at 36 C, whereas types 1 and 3 parainfluenza viruses agglutinated only guinea pig erythrocytes. Thus parainfluenza viruses were divided into two groups by the presence or absence of hemagglutinins for green monkey erythrocytes. Identification of these parainfluenza isolates, employing HI microtechnique was simple and reliable, even with the first passage harvest, when guinea pig erythrocytes were used and the test read at 36 C. Specific standard antisera for these parainfluenza viruses were prepared by immunizing chickens intravenously and bleeding within a short period. These type-specific antisera were useful for the identification of parainfluenza isolates by HI test.  相似文献   

18.
Erythrocytes of different animal species have variable hemolytic sensitivity to staphylococcal alpha toxin. Specific and non-specific binding of toxin was measured using fluorescein-labelled toxoid. These studies indicate that toxoid binding to erythrocytes increases with concentration for all species tested. Scatchard plot analyses of 35 animals representing seven species indicate that rabbit, pig, cow, and chicken erythrocytes possess 125 980, 103 920, 82 500, and 41 200 receptors per cell, respectively. The number of receptors remains constant over a period of at least 10 days. No detectable receptors were found for human, rat, and guinea pig erythrocytes. A correlation coefficient of 0.992 exists between receptor number and hemolytic sensitivity for those species having receptors. Variation in hemolytic sensitivity is governed by receptor number and not by variation in the dissociation constant. A threshold sensitivity of 37 000 receptors per cell has been calculated. Since species lacking detectable receptors have considerable sensitivity to hemolysis, it is proposed that two binding mechanisms, specific and non-specific, exist which prepare erythrocytes for destruction.  相似文献   

19.
Rapid kinetic techniques were used to measure the transport of uridine in pig erythrocytes in zero-trans entry and exit and equilibrium exchange protocols. The kinetic parameters were computed by fitting appropriate integrated rate equations to the time-courses of transmembrane equilibration of radiolabeled uridine. Transport of uridine conformed to the simple carrier model with directional symmetry, but differential mobility of substrate-loaded and empty carrier. At 5 degrees C, the carrier moved about 30-times faster when loaded than when empty. Uridine transport was inhibited in a concentration-dependent manner by nitrobenzylthioinosine and dipyridamole and the inhibition correlated with the binding of the inhibitors to high-affinity binding sites on the cells (Kd about 1 and 10 nM, respectively). Thus, in its kinetic properties, differential mobility when empty and loaded, and sensitivity to inhibition by nitrobenzylthioinosine and dipyridamole, the transporter of pig erythrocytes is very similar to that of human erythrocytes. Also, the total number of high-affinity binding sites for nitrobenzylthioinosine and dipyridamole/cell were similar for the two cell types and the [3H]nitrobenzylthioinosine-labeled carrier of pig erythrocytes, just as that of human red cells, was mainly recovered in the band 4.5 protein fraction of Triton X-100-solubilized membranes. However, sodium dodecylsulfate-polyacrylamide gel electrophoresis of photoaffinity-labeled band 4.5 membrane proteins indicated a slightly higher molecular weight for the transporter from pig than human erythrocytes. We have also confirmed the lack of functional sugar transport in erythrocytes from adult pigs by measuring the uptake of various radiolabeled sugars. But in spite of the lack of functional sugar transport we recovered as much band 4.5 protein from pig as from human erythrocyte membranes.  相似文献   

20.
Hemolysin and Peroxide Activity of Mycoplasma Species   总被引:13,自引:3,他引:10  
Various methods for the detection of hemolysin production by Mycoplasma species were compared. Inoculation of blood-agar by the push-block method and by use of concentrated mycoplasma cell suspensions was compared with the agar-overlay technique. The preferred method was direct surface inoculation of concentrated suspensions onto the blood-agar. Among the conditions tested, refrigeration of 48-hr cultures gave the best results. A wide variety of mycoplasma species were tested for hemolytic activity towards rabbit, sheep, guinea pig, duck, and chicken bloods. Guinea pig erythrocytes were found to be the most susceptible to lysis by mycoplasma, and rabbit erythrocytes were found to be the least susceptible. A sensitive technique for the detection of peroxide production by mycoplasma strains, employing agar containing benzidine and sheep blood, was used. With this method, peroxide production could be correlated with hemolysis on blood-agar. Peroxidase and catalase inhibited both the benzidine reaction and hemolysis. It was concluded that the major hemolysin of the Mycoplasma species examined is a peroxide.  相似文献   

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