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At least 1,099 records · Page 61Linked to original sources
PubMed1989

Occurrence of intracytoplasmic inclusion bodies in the digestive epithelium of fallow deer (Dama dama L).

Intracytoplasmic inclusion bodies were observed in the digestive epithelium of fallow deer (Dama dama L) suffering from bovine virus diarrhea/mucosal disease. Similar inclusion bodies were also found in the ruminal epithelium of fallow deer subjected to overfeeding by supplementary food. Inclusion bodies were not found in the upper alimentary mucosa of clinically healthy deer but were frequently found when these tissues were subjected to autolysis. At electron microscopical studies the inclusion bodies were found to consist of granular protein-like material encircled by a single membrane. Such inclusion bodies may constitute a non-specific degenerative cell response which could be elicited by diverse factors including autolysis.

Animals↗
PubMedDate not supplied

[Affinity chromatography of human gamma-thrombin on fibrin-agarose].

gamma-Thrombin was produced during autolysis or limited proteolysis of coagulant gamma-thrombin. This thrombin form loses its ability to coagulate fibrinogen but preserves the esterase and amidase activity on the low-molecular-weight synthetic substrates. This evidences for the integrity of the active site of gamma-thrombin and for the integrity break of the enzyme molecule region responsible for the binding with fibrinogen. gamma-Thrombin with the minimal coagulating activity, possessing high esterase and amidase activity is obtained. Fibrin-agarose possessing affinity to gamma-thrombin and specifically not binding gamma-thrombin was used to remove admixtures of the coagulant gamma-thrombin from the preparations of gamma-thrombin obtained during the enzyme autolysis.

Catalysis↗
PubMed1988

Fine structural alteration in the atrioventricular junctional conduction tissues of the dog heart during severe ischaemia.

To define the fine structural changes produced in the atrioventricular junctional conduction tissues by severe ischaemia, 3 sets of specimens from 37 dogs were examined by light and electron microscopy using a large specimen resin-embedding method. Surgical control material was taken from 18 open-chest animals maintained under anaesthesia for up to 6 h, autolysis control material from 10 excised normal hearts maintained at 37 degrees C in vitro for up to 4 h, and ischaemic material from 8 animals in which the septal and distal left circumflex coronary arteries were occluded for 15 min to 3 h. Surgical control material was found to be within normal limits, whereas both autolysed and ischaemic showed initially mild fine structural alteration, which increased progressively in severity with time and was comparable in both sets. All cell types showed loss of glycogen granules, mitochondrial swelling, dilatation of sarcoplasmic reticulum vesicles, clumping of nuclear chromatin and ultimately varying degrees of generalised cell swelling. Intramitochondrial dense inclusions also were prominent in autolysis but not ischaemia. These changes progressed faster in nodal cells than in His bundle/bundle branch cells, which retained considerable quantities of glycogen for at least 60 min. The slower development of irreversible alteration in His-Purkinje cells suggests that they may be relatively more resistant to ischaemia, whilst the low incidence of intramitochondrial dense inclusions in vivo suggests a beneficial effect of collateral blood flow.

Animals↗
PubMed1985

Acid proteases and histologic correlations in experimental ulceration in vitamin A deficient rabbit corneas.

Although xerophthalmia due to severe vitamin A deficiency is the leading cause of childhood blindness in the underdeveloped countries, little is known about the proteases (other than collagenase) that are involved in the degradative mechanism. The degree of cellular autolysis and stromal degradation observed histologically in early stages of xerophthalmia and in ulcerating corneas in vitamin A deficient rabbits in this study were, in general, proportional to the levels of the proteases studied. The only major histologic and ultrastructural alteration observed in early xerophthalmic corneas was autolysis of superficial epithelial and stromal cells. In contrast, in the ulcerating corneas the stroma was infiltrated heavily with inflammatory cells and extensive stromal degradation was observed in the central necrotic region of the lesions. Maximal proteolytic activity toward hemoglobin was observed at pH 3.3 for corneal extracts from normal (N) and pair-fed control (C) rabbits and rabbits with early xerophthalmia (X) and ulcerating xerophthalmia (U) corneas. This activity was a cathepsin D-like enzyme per cornea that had a ratio of 1:1:3:16 in the N, C, X, and U corneas. The ratio of cathepsin B-like activity per cornea for N, C, X, and U corneas was 1:2:2:10.

Animals↗
PubMed1979

Factors influencing mouse heart creatine kinase efflux and ultrastructure.

An isolated mouse heart model has been developed to study the extracellular factors which influence the loss of myocardial enzymes. When added to a tris-HCl buffer/salt mixture at 25 degrees C, glucose, phosphate ion, increased osmolarity, oxygen exclusion and calcium reduced enzyme leakage. Of these, calcium effects on enzyme leakage and ultrastructure were assessed in detail. Concentrations less than or equal to 10(-4) M had no significant effect on enzyme efflux over a 5 hour period. At higher concentrations (10(-3) and 10(-2) M Ca2+), creatine kinase (CK) efflux was significantly altered in a time dependent fashion. In the first hour, 10(-3) and 10(-2) M Ca2+ reduced CK leakage to 33% and 25% of the control values, respectively; and to about 50% of the control values in the second and third hours. This protective effect was lost between the third and fifth hours, when an enzyme efflux 80% greater than control was observed. These studies indicated that CK leakage from mouse heart can be retarded for up to 3 hours by appropriate Ca2+ concentrations. The initial ultrastructural change, in the absence of Ca2+, was a dilatation of the transverse tubules, which gradually enlarged by coalescence. This was followed by a gradual disintegration and ultimate condensation of the myofibrils leaving altered mitochondria floating freely in an apparently intact sarcolemmal bag. These changes appeared to be delayed by Ca2+ for 3 hours, after which no protective effect was evident. Thus, CK leakage is a measure of myocardial autolysis, and numerous simple measures can retard this autolysis for several hours. This raises the possibility of prolonging the preservation of the normal heart in vitro.

Animals↗
PubMed1984

Staining in normal and ischemic human myocardium. A study of myoglobin, IgG, glycogen, and diastase-PAS.

Using the indirect immunofluorescence technique, we studied the distribution of myoglobin in normal and ischemic human myocardium obtained at autopsy and at surgery. Glycogen, diastase-PAS staining of the sarcoplasm, and IgG were also studied and compared with the structure of the lesions and the distribution of myoglobin. The surgical material we used was largely free of autolysis and was the most satisfactory. Prolonged fixation of tissues in formaldehyde solution or perfusion fixation of autopsy specimens both proved to be unsatisfactory as myoglobin was absent from the myocardium. This loss presumably represents diffusion of myoglobin due to autolysis and the method of fixation. Another group of autopsy specimens that was briefly fixed by immersion in formaldehyde solution prior to processing was more satisfactory. Although they showed some extracellular diffusion of myoglobin, the autolyzed normal areas could still be clearly differentiated from the autolyzed ischemic areas.

Amylases↗
PubMed1978

A comparison of procedures to determine free fatty acids in rat heart.

The level of free fatty acids in intact tissues has been found to be low but is known to rise in proportion to the extent of autolysis. Therefore, the high levels of free fatty acid reported in the cardiac lipids of rats fed rapeseed oil were reinvestigated using two different procedures for homogenization. Quick freezing and pulverization at dry ice temperature followed by lipid extraction was found to give lower values of free fatty acids (200 microgram/g of wet heart tissue) than the more commonly used technique of employing rotating blade-type homogenizers (greater than 1700 microgram/g of wet heart tissue). The amount of diglycerides was found to be 3 times greater when the latter method was used. The high levels of free fatty acid and diglyceride suggest that extensive autolysis occurs during homogenization with a rotating blade-type homogenizer. Freezing and pulverization at dry ice temperature is therefore recommended for determining intact lipid classes in rat heart.

Animals↗
PubMedDate not supplied

[Peptide hydrolase activity of blood serum, myocardium and skeletal muscles of rats under different states of hyperbaric oxygenation].

Intensity of autolysis and proteolysis (hemoglobin as a substrate) of blood serum, myocardium and skeletal muscles was determined under normal conditions and under the effect of 2.0, 3.5 at. abs. of oxygen for 60 min and 5 at. abs. for 10 and 60 min. Under the effect of 3.5 and 5 at. abs. of oxygen there occurs a considerable increase in a degree of autolysis and proteolysis of the studied tissues as compared to the effect of 2 at. abs. of oxygen. But. these changes are not specific for the oxygen toxic doses.

Animals↗
PubMed1984

Avoidance of false-negative blood culture results by rapid detection of pneumococcal antigen.

False-negative blood culture results may occur in children with pneumococcal bacteremia due to bacterial autolysis. We describe four patients with pneumococcal bacteremia whose aerobic blood cultures showed partial or complete autolysis of the pneumococci. Pneumococcal antigen, however, was rapidly detected in media from the blood culture bottles, using an agglutination assay. Processing of the media before analysis was necessary to prevent nonspecific agglutination and to allow the detection of a specific reaction. It is important that physicians and laboratory personnel be aware that pneumococci may rapidly autolyze during incubation, yielding false-negative culture results. Antigen detection methods may provide rapid and specific identification of the etiologic agent.

Agglutination Tests↗
PubMed1984

Characterization of cathepsin B-like proteinase from ascitic fluid of patients with primary liver cancer.

Ascitic fluid of patients with primary liver cancer was shown to contain a latent thiol proteinase which can be activated by pepsin treatment or by autolysis at acidic environment. This enzyme resembles cathepsin B (EC 3.4.22.1) in many physical-chemical properties including substrate specificity, requirement for thiol activators and inhibition both by thiol blocking reagents and by peptidyl diazomethyl ketones, but has a higher molecular size even after activation. Pepsin treatment and autolysis reduce its Mr from 41 800 to 33 400 and 27 700, respectively, but all these forms are larger than human liver cathepsin B. The latent enzyme may be, therefore, an enzyme--inhibitor complex or an inactive precursor of cathepsin B due to an altered processing in Golgi endoplasmatic reticulum-lysosome compartment.

Ascitic Fluid↗
PubMed1983

Studies on the mechanism of bacterial resistance to complement-mediated killing. III. C5b-9 deposits stably on rough and type 7 S. pneumoniae without causing bacterial killing.

Gram-positive cocci resist direct killing by serum. The mechanism of resistance was studied by measuring consumption of terminal complement components from serum and uptake of purified, radiolabeled C7 and C9 on rough and encapsulated type 7 Streptococcus pneumoniae. Extensive consumption of C5, C7, and C9 occurred when 5 X 10(8) rough or type 7 pneumococci were incubated for 1 hr in 10% pooled normal human serum (PNHS). Approximately 10,000 molecules of C7 and C9 bound per organism during the same period of incubation. Twenty to 30% of C7 and C9 was released from rough organisms. Release was not due to autolysis since it occurred with glutaraldehyde-fixed organisms as well as in S. pneumoniae that were rendered resistant to autolysis by growth in ethanolamine. Between 10 and 30% of bound 125IC9 counts were eluted from the rough and type 7 organisms by incubation in 1 M NaCl or 0.01 M EDTA, which suggests that bound C5b-9 was not attached by predominantly ionic interactions. Elution of 44 to 74% of 125IC9 from live and glutaraldehyde-fixed organisms by 1% sodium deoxycholate suggests that hydrophobic bonds are involved in C5b-9 attachment. Trypsin cleaved 67 and 55% of 125IC9 counts from live rough and type 7 S. pneumoniae, respectively which indicates that the bound complex is not protected by the cell wall from proteolytic attack. Serum resistance in S. pneumoniae does not represent a failure to form C5b-9 on the bacterial cell wall but apparently reflects a failure of the bound complex to penetrate the thick peptidoglycan layer.

Blood Bactericidal Activity↗
PubMedDate not supplied

[Activity of arginase and proteolytic processes in the brain and liver of rats in cold acclimatization].

The activity of arginase, neutral peptidohydrolase (protaminase) and total intensity of autolysis were determined in the brain and liver of rats on the 1st, 3d, 30th and 45th days animal stay at a temperature of 2-4 degrees C. in the process of rats acclimatization to cold there occurs a correlation in the brain - between the activity of arginase and neutral peptidohydrolase, in the liver - between the arginase activity and total proteolytical activity (autolysis).

Acclimatization↗
PubMed1980

[Bimolecular protein-protein interactions in microcapsules].

It was shown that protein-protein interactions in microcapsules are possible. A mixture of two proteins at high concentrations was microencapsulated at acidic pH values of the aqueous phase under the following conditions: use of the double emulsification method, use of the inert filler--5% polyethylenimine for the formation of spherical non-aggregated microcapsules containing a small quantity of the protein in the membrane, and use of polycarbonate as a film-forming polymer. The kinetics of trypsin inhibition by soya inhibitor, trypsin autolysis and trypsinogen autoactivation were studied. Encapsulation did not influence the rate constant of the trypsin autolysis reaction and decreased to some extent the specific rate of trypsinogen autoactivation.

Emulsions↗
PubMed1994

Purification of the extracellular acidic proteases of Dichelobacter nodosus.

Dichelobacter nodosus, a Gram negative obligate anaerobe and causative organism of ovine footrot, secretes a family of extracellular acidic serine proteases with pI's in the range of 5.2 to 5.6, and a basic serine protease with a pI of approximately 9.5. Four acidic proteases (V1, V2, V3 and V5) from virulent and five acidic proteases (B1 to B5) from benign strains of D. nodosus were purified by chromatography on Sephadex G-100 and DEAE-Sepharose CL-6B. Proteases V2, V5 and B5 were found to yield two forms (a and b) on purification which probably arise from limited autolysis of the parent molecule. Amino acid compositions, peptide profiles produced on autolysis and apparent Mr on SDS-PAGE of proteases V1-V3 showed that they were similar to each other and to proteases B1 to B4, and that these proteases were clearly distinct from proteases V5 and B5, which were found to be identical.

Amino Acid Sequence↗
PubMedDate not supplied

The difference in DNA ploidy pattern between some canine and human neoplasms appears to be genuine and a reflection of dissimilarities in DNA aneuploidy evolution.

In a reaction to the article by Deitch et al, (Anticancer Res 13: 2117-2118, 1993) evidence is presented that flow cytometrically detected DNA-hypodiploidy in canine neoplasms is genuine and not an artefact caused by autolysis or chemotherapy. Intervals between removal of tumors and freezing in our studies were much shorter (average 15 min, maximum 30 min) than e.g. for human breast tumors in which the percentage of hypodiploidy is about 2%. Also average CVs for the G0, 1 peaks in our FCM analysis of canine tumors (mammary 2.27 + 0.06, n = 179); thyroid 2.57 + 0.13, n = 88) were equal to or less than those usually found in the comparable human tumors. Biological arguments in favor of the existence of genuine hypodiploid stemlines are the finding of tetraploidized subclones of the original hypodiploid clone, the reappearance of the same hypodiploid stemline in distant metastases during clinical follow up, and the isolation of a cytogenetically and flow cytometrically hypodiploid cell line from a primary canine mammary carcinoma. It is concluded that Deitch et al, incorrectly have invoked autolysis as a source of hypodiploidy in our original studies on canine neoplasms. Our evidence for interspecies differences in the evolution of aneuploidy in tumors of the same organ therefore remains unchallenged.

Aneuploidy↗
PubMed1975

[Metabolites toxic for penicillin biosynthesis in P. chrysogenum fermentation].

Substances toxic for biosynthesis of penicillin accumulated in the medium at the end of the process during penicillin fermentation. Accumulation of such substances was associated with the mycelium autolysis. Addition of nutrient substances as soon as they are consumed prevented autolysis of the mycelium and accumulation of the toxic metabolites.

Absorption↗
PubMedDate not supplied

[Features of autolytic restructuring of lipids in plasma, serum, and blood clots].

Quantitative composition and amount of main lipid fractions were studied by means of microthin-layer chromatography in blood clot free of cell elements, in blood serum and plasma obtained from volunteers as well as their alterations were estimated in dynamics of autolysis. Dissimilar alterations were detected in total lipids and their individual fractions in the preparations studied. Under conditions of incubation the lipid component was found to be highly labile in blood plasma and serum, where total content of lipids was distinctly decreased, while the lipids content was not considerably altered in blood clot. Content of phospholipids was most distinctly decreased with simultaneous accumulation of free fatty acids in all the preparations studied. The most considerable transformations were observed within early steps of autolysis. Dissimilar composition and activity of the enzymatic systems involved in biodegradation and biotransformation of lipid components as well as specific metabolic relations between lipids may be responsible for these differences in the type and rate of autolytic transformations of lipid components in blood plasma, serum and clot.

Cholesterol↗
PubMedDate not supplied

[Study of autolytic changes in human myocardial proteins by two-dimensional electrophoresis].

Alterations of myocardial proteins were studied in the left ventricular tissue of adult persons and fetuses during natural autolysis. The most pronounced alterations were observed in proteins from regions of myosin light chains, region 119 and the region of muscle enzymes. When autolysis was studied in the myocardium and skeletal muscle, proteolytic alterations were observed in skeletal muscles later.

Adult↗