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At least 19 recordsLinked to original sources

PubMed1977

Adenine nucleotide transport in sonic submitochondrial particles. Kinetic properties and binding of specific inhibitors.

1. A procedure for preparation of sonic submitochondrial particles competent for adenine nucleotide transport is described. ADP or ATP transport was assayed, in the presence of oligomycin, in a saline medium made of 0.125 M KCl, 1 mM EDTA, 10 mM 4-morpholinopropane sulfonic acid buffer, pH 6.5. 2. Sonic particles transport ADP and ATP by an exchange diffusion process. Externally added ADP (or ATP) is exchanged with internal ADP and ATP with a stoichiometry of one to one. The V value for ADP transport 5 degrees C was between 2 and 3 nmol/min per mg protein. 3. The transport system in sonic particles is specific for ADP and ATP. It is strongly dependent on temperature. The activation energy between 0 and 9 degrees C is approx. 35 kcal/mol. The optimum pH is 6.5, 4, Like in intact mitochondria, externally added ADP is transported into sonic particles faster at a given concentration than externally added ATP. The V value for ADP transport is 1.5-2 times higher than the V value for ATP transport. 5. The transition from the energized to the deenergized state in sonic particles results in a decrease of the pH gradient across the membrane (internal pH less than external pH) and in a 2-4 fold increase in the Km value for ATP. This latter effect is opposite that found for transport of added ATP in intact mitochondria (Souverijn, J.H.M., Huisman, L.A., Rosing J. and Kemp, Jr., A. (1973) Biochim. Biophys. Acta 305, 185-198). Energization has no effect on the V value of ATP transport in sonic particles. 6. In contrast to intact mitochondria, inhibition of ADP transport in sonic particles by bongkrekic acid does not have any lag-time and does not depend on pH. The inhibition caused by bongkrekic acid is a mixed type inhibition with a Ki value of 1.2 micronM. Atractyloside and carboxyatractyloside do not inhibit ADP transport in sonic particles, unless the particles have been preloaded with these inhibitors during the sonication. 7. Palmityl-CoA added to sonic particles inhibits efficiently ADP transport. The mixed type inhibition found with palmityl-CoA has a Ki value of 1.6 micronM. 8. [3H]Bongkrekic acid binds to sonic particles readily and with high affinity. Bongkrekic acic binding to sonic particles does not depend on pH and it has a saturation plateau, corresponding approximately to 1.3 mol of site per mol of cytochrome a. The number of [3H]atracytloside binding sites is much lower (one-fifth of the bongkrekic acid). External carboxyatractyloside does not compete with [3H]bongkrekic acid for binding to sonic particles. However, when carboxyatractyloside is present inside the particles, it inhibits the binding of [3H]bongkrekic acid.

Adenine Nucleotides↗

PubMed1975

Inactivation of viruses and bacteria by ozone, with and without sonication.

Selected organisms with public health significance were placed in a reaction chamber for treatment by ozonation, by ozonation and sonication, by sonication, or by sonication during oxygenation. Vesicular stomatitis virus, encephalomyocarditis virus, GDVII virus, Staphylococcus aureus, Pseudomonas fluorescens, Salmonella typhimurium, enteropathogenic Escherichia coli, Vibrio cholerae, and Shigella flexneri were inactivated by treatment with ozone. When microorganisms were suspended in phosphate-buffered saline, they were inactivated rapidly by treatment with ozone. However, microorganisms suspended in secondary effluent from a wastewater treatment plant required longer contact times with ozone for complete inactivation. Simultaneous treatments by ozonation and sonication reduced the contact time for complete inactivation of microorganisms in secondary effluent. Treatment by sonication alone or sonication and oxygenation did not inactivate microorganisms. Therefore, the simultaneous treatment of microorganisms in secondary effluent with ozone and sonication resulted in a synergistic effect.

Animals↗

PubMed1979

The effect of sonicated serum on growth of normal and leukaemic human cells in agar cultures.

The existence of circulating factors in blood of possible importance for granulopoiesis was investigated by examining the effect of sonicated serum on agar cultures of human haematopoietic cells. Ultrasound treatment of serum can activate enzymes normally bound to carrier proteins. In normal bone marrow cultures, growth was inhibited by sonicated serum when the cells were cultured in a single layer without exogenous colony-stimulating factor (CSF) included in the culture, while an enhancing effect with a 2--5 fold increase in the number of colonies was seen in feeder layer-stimulated cultures. Morphologically, in contrast to the normal change to eosinophils and monocytes-macrophages during the culture period, the cultures with sonicated serum added showed continuous growth of neutrophils and no increase of other cell types. Experiments using tritiated thymidine indicated that the enhancing effect of sonicated serum involved marrow cells which were more prone to thymidine S-phase kill. The effect of sonicated serum was further evaluated in cultures from patients with leukaemia. In AML in relapse, feeder-layer stimulated cultures of bone marrow cells were inhibited (11/14 cases) by sonicated serum, while reversion to the normal enhancing pattern was seen for patients in remission.

Blood↗

PubMed1976

Interaction of ultrasound with neoplastic tissue. II. Systemic effects after local sonic irradiation.

Local sonic irradiation was applied to subcutaneously implanted Furth-Columbia rat Wilms' tumor. The weight and the rate of tritiated thymidine uptake were measured in host organs distal to the application field. Kidney and spleen weights were inhibited by the Wilms' tumor, and sonication of the tumor removed all or part of this inhibition. Liver weight was increased after sonication of tumor-bearing rats but not in nontumor-bearing rats. This may have been a response to tumor-specific substances released into the circulation by sonic destruction of tumor tissue. The adrenals enlarged as a response to the stresses of both tumor-bearing and of sonication. Animals were implanted on both sides with the Wilms' tumor and on without any break in the growth curve while the sonicated right tumor was inhibited. These data suggest that the therapeutic effect of ultrasound is due solely to local factors and that systemic sequelae of some irradiation are unrelated to tumor inhibition.

Adrenal Gland Neoplasms↗

PubMed1978

A defined molecular-weight distribution of deoxyribonucleic acid after extensive sonication.

Concentrated solutions of low-molecular-weight DNA (Mw=35000) with a known molecular-weight distribution can be prepared in several hours, and require no additional fractionation procedures. This is achieved by sonication of the DNA in 1.0 M-NaCl at high power at 0--2 degrees C. No denaturation of the DNA is detectable, even after 8h of continuous sonication. After 2h, the molecular-weight distribution of the total DNA sample is that of the most probably Schulz distribution, described by-Mn:-Mw:-Mz ...=1:2:3 ...etc. Such a molecular-weight distribution is expected for a random break-up of indefinitely long macromolecules and indicates that the sonication process is essentially by random double-strand scission. DNA was also sonicated in the presence of ligands capable of modifying the DNA tertiary structure. The results support the idea that inflexibility of the DNA is required for efficient sonic degradation.

Chromatography, Gel↗

PubMed1977

Sonication as a tool for the study of adenylyl cyclase activity.

The technique of sonication was applied in studying adenylyl cyclase activity of cultured fibroblasts. Exposure of BHK 21 c/13 to brief periods of low power sonication gives cell preparations with greater basal, fluoride and hormone sensitive adenylyl cyclase activites than those of broken cell preparations of homogenized cells. The sonicated cells provide a convenient method to study adenylyl cyclase since they are added directly to the adenylyl cyclase reaction vessels without further processing. Maximal epinephrine stimulated activity in sonicated cells is nearly equivalent to that activated by sodium fluoride, but the apparent affinity of the enzyme system is similar to that of broken cell preparations. Furthermore, broken cell preparations of sonicated cells possess greater adenylyl cyclase activity than broken cell preparations of unsonicated cells. This procedure may provide a useful tool for the analysis of the hormonal regulation of adenylyl cyclase activity of isolated cells.

Adenylyl Cyclases↗

PubMed1977

Identification of fibrin oligomers in sonicated fibrin clots.

Clots of bovine fibrin, with both coarse and fine structure, and ligated to different extents by fibrinoligase, have been broken up by ultrasonic agitation and the sonicates have been examined by ultracentrifugal sedimentation. Sonication is followed by gross aggregation of the fragments unless guanidine hydrochloride is introduced (order of 1 M). In that case, sonicates of gamma-ligated fine clots contain two species whose sedimentation coefficients correspond to fibrin monomer and an oligomer with twice the monomer cross-section area and at least 20 monomer units, presumably with the structure of lateral dimerization with staggered overlapping. If the gamma ligation is incomplete, shorter oligomers are identified. The monomer and oligomer with degree of polymerization greater than 20 appear also in sonicates of coarse clots, but in smaller amounts, the principal product consisting of larger aggregates. The implications of these results with respect to metastability of the fine clot and the pattern of polymerization are discussed.

Animals↗

PubMed1976

Effect of sonic treatment on pure cultures and aggregates of bacteria.

Pure cultures of a variety of bacteria were treated with ultrasonic energy using a sonic probe. Fractions of organisms killed at different sonic energies were calculated, and Streptococcus mutans was 600 times more resistant than Fusobacterium nucleatum, the most sensitive organism tested. The effects of sonic treatment on aggregates of bacteria were examined, and the results were interpreted as a model of the events that probably occur during the sonic dispersion of dental plaque.

Actinomyces↗

PubMed1976

Comparison of antigens in sonic and pressure cell extracts of Mycobacterium tuberculosis.

Comparisons were made of the yield, chemical content, and biological activity of filtrates and extracts obtained by sonic and pressure cell disruption of bacilli from 4- and 8-week-old Proskauer and Beck cultures of the H37Rv strain (TMC no. 102) of Mycobacterium tuberculosis. The culture filtrates were dialyzed, freeze-dried, reconstituted in saline, and sterilized by membrane filtration. The viable bacilli were washed and resuspended in distilled water and subsequently disrupted either by sonication in the cold for 15 or 30 min or by treatment at 20,000 or 40,000 lb/in2 in a pressure cell. The resulting extracts were clarified by centrifugation, concentrated, and sterilized by filtration. All preparations were adjusted to contain 10 mg of solids (dry weight)/ml and were analyzed quantitatively for protein, deoxyribonucleic acid, ribonucleic acid, polysaccharide, and lipid content. Separation patterns obtained by gradient acrylamide gel electrophoresis, as well as by one- and two-dimensional immunoelectrophoresis, provided the basis for qualitative comparisons of the culture filtrates and cell extracts. Three-point dose-response curves also were used to compare the preparations for skin test reactivity in BCG-vaccinated guinea pigs. It was concluded that, although there were no consistent differences in chemical content or biological activity between the preparations, a 15-min sonic treatment appeared to be the most suitable method for preparation of bacillary extracts based on yield of active components and ease of preparation.

Animals↗

PubMed1978

The effects of sonication, freezing and lyophilization on JMV leukosis strain.

JMV lymphoblastic leukemic cells were subjected to sonication, followed by freezing and lyophilization in an attempt to learn the tolerance of JMV cells to these treatments. Sonication experiments indicated that a high percentage of cell breakage (greater than 89%) is necessary for any decrease in lethality to be observed. Freezing experiments involving a wide range of cryoprotectors demonstrated 2M glycerol to be the best for JMV preservation. Subsequent freeze-drying of sonicated, frozen JMV preparations, of high titer, consistently resulted in all loss of lethality.

Animals↗

PubMed1977

Light-activated calcium release from sonicated bovine retinal rod outer segment disks.

Calcium trapped within sonicated and resealed bovine rod outer segment disks is released upon light exposure with a stoichiometry of 0.75 +/- 0.05 calcium for each rhodopsin bleached. The amount of calcium liberated is proportional to the amount of bleaching in the range of 20 to 100% bleaching and is relatively insensitive to the internal trapped calcium concentration. The results are obtained using a flow system in which the disk membrane vesicles are adsorbed on glass particle supported by a filter. The external calcium is washed away and subsequent calcium release is monitored by collecting fractions of the effluent before, during, and after light exposure. Disks that are sonicated and allowed to reseal prior to incubation with 45Ca show no change in calcium efflux upon bleaching. The light-activated calcium release is also eliminated if disks sonicated in the presence of 45Ca are treated with a calcium ionophore prior to bleaching. The results demonstrate that the light-released calcium comes from the disks and not from the external disk surface. Lowering temperature to 3--4 degrees C surpresses the light-stimulated release, implicating a transition after the formation of metarhodopsin I in the transport process. The resluts suggest a model for the disk in which each bleached rhodopsin functions as a "one-shot carrier" to transport a single calcium ion across the membrane.

Animals↗

PubMed1979

The 'enzyme-probe' method for characterizing metabolite pools. The use of NAD-glycohydrolase in human erythrocyte sonicate as a model system.

1. An approach for testing the homogeneity of metabolite pools is described. An alien enzyme that can attack the metabolite in question is introducted into the system studied. By analyzing the time-course of decomposition of the metabolite it can be decided whether the pool is homogeneous in respect of reactivity towards the probe-enzyme or can be divided into fractions of different reactivities. 2. The information obtainable from such experiments is illustrated by the case of human erythrocyte sonicate as model system with NAD-glycohydrolase as probe-enzyme. The nicotinamide adenine dinucleotide pool in the concentrated sonicate could be resolved into three fractions (I, II and III) with half-lives of about 1, 7 and 240 min, respectively. Fraction I is free NAD, fraction II is NAD bound to glyceraldehyde-3-phosphate dehydrogenase, and fraction III is coenzyme strongly bound to some, so far unidentified, protein. Sonicate glycolysis seems to require only fraction II and is unable to use fraction III under the experimental conditions applied. 3. The scope of application of the enzyme-probe method is discussed.

Erythrocytes↗

PubMed1976

Sonic fragility of the head-tail bond of bacteriophage P22.

The binding of tail parts to the head of phage P22 is normally irreversible, but after adsorption to host cells sonication releases many of the tail parts intact. This release is dependent on the power of sonication, but is independent of the length of sonication from 2 to 32 s. This phenomenon has been used to show that the upper limit of the number of P22 particles that can bind to a cell is no lower than 700.

Adsorption↗

PubMed1978

Temperature dependence of calcium-induced fusion of sonicated phosphatidylserine vesicles.

We have measured the temperature dependence calcium-induced fusion of sonicated phosphatidylserine vesicles. The vesicles were incubated in the presence of calcium at a specified temperature until the resulting aggregation or fusion process had gone to completion. EDTA was then added and the resulting final size of the vesicle population was measured by using dynamic light scattering. This final size was plotted against incubation temperature to show the temperature dependence of calcium-induced fusion. This curve has a peak near 11 degrees C which may be associated with the phase transition of the sonicated phosphatidylserine vesicles in the presence of calcium prior to the aggregation or fusion process.

Animals↗

PubMedDate not supplied

Extraction of human and rabbit acrosomes: a comparison of sequential and sonication methods.

Two methods for the extraction of acrosomal membranes and enzymes from both human and rabbit spermatozoa were compared. Treatment of spermatozoa with hypotonic MgCl2 (0.05 M) solution causes removal of the plasma membrane, vesiculation, disruption and removal of the outer acrosomal membrane posterior to the equatorial segment with accompanying loss of soluble acrosomal material. Subsequent exposure to Hyamine 2389 and Triton X-100 removes acrosomal material bound to the inner acrosomal membrane with concomitant solubilization of this membrane. The MgCl2 extract from rabbit spermatozoa contained a higher yield of hyaluronidase, acrosin, and total proteinase activities, whereas the subsequent detergent extracts contained higher yields of both arylsulfatase A and B activities. By comparison, after 4 minutes of sonication to separate heads and tails, both rabbit and human spermatozoa when viewed by transmission electron microscopy showed alterations of plasma and outer acrosomal membranes with considerable loss of the acrosomal contents. Analysis of acrosomal enzymes indicates the greatest percentage of all the enzymes assayed was located in the extract obtained by sonication in contrast to either the separated head or tail fractions used for further subcellular extraction. Subsequent treatment with Hyamine and Triton yields only minimal amounts of enzyme activity.

Acrosin↗

PubMed1979

Effects of pinealectomy and pineal incubation medium and sonicates on insulin release by isolated pancreatic islets in vitro.

The present studies were designed to investigate the mechanism of previously-reported nocturnal hyperinsulinemia in the pinealectomized rat. Isolated islets were obtained from anesthetized control, sham-pinealectomized and pinealectomized rats, with 5 rats per surgical groups, during the early dark phase of the daily lightdark cycle. Batches of 3 islets each were incubated in various combinations of 2, 10 or 30 mM glucose with control buffer, medium in which cerebral cortex or pineal glands had previously been incubated for 2 hours, or sonicates of these same tissues. Insulin released into the culture medium was measured by radioimmunoassay. A significant hypersecretion of insulin was demonstrable in the islets from the pinealectomized animals. A stimulatory effect of both pineal medium and sonicates upon insulin release was similarly observed. Neither of these effects displayed an interaction with the concentration of glucose in the islet incubation medium and they, therefore, appear to be mediated by a mechanism which operates independently of stimulation by glucose. These results indicate that the rat pineal gland can exert direct effects upon insulin release from the islets, possibly through a humoral route. Further studies are in progress to characterize the nature and mode of action of the insulinotropic agent present in and released from the pineal gland.

Animals↗

PubMed1978

Human response to house vibrations caused by sonic booms or air blasts.

Descriptions of the effects of sonic booms of air blasts by observers in buildings have included such statements as "noticeable vibrations" in addition to phrases such as "the house rattles," "the windows rattle," or "bric-à-brac rattles." Analysis of studies of human response to vibrations, vibration complaints in the Toronto area, special tests by Kryter at Edwards Air Force Base, and laboratory studies of human response to sonic booms show that perceived vibration is not normally a factor that contributes significantly to human response to airborne, large-amplitude impulse noise. Rather, human response is solely the result of the impulse noise itself and of audible noise due to induced radiation from vibrating surfaces.

Affect↗

PubMed1978

Degradation of the polysaccharide component of gonococcal lipopolysaccharide by gonococcal and meningococcal sonic extracts.

An extract made from the supernatant of Neisseria gonorrhoeae Gc2 strain 1291 degraded the Gc2 polysaccharide antigen. Chemical analysis of this polysaccharide indicated it contains glucose, galactose, glucosamine, galactosamine, glucosamine-6-phosphate, heptose, 2-keto-3-deoxyotonate, and ethanolamine and is the polysaccharide component of gonococcal lipopolysaccharide. Degradation of the polysaccharide by sonic extracts resulted either in complete loss of antigenicity and immunogenicity or in partial degradation to subunits that could inhibit the Gc2-specific hemagglutination inhibition. The factors responsible for degradation were destroyed by heating at 100 degrees C for 5 min or by Pronase digestion, but were unaffected by ribonuclease, deoxyribonuclease, Mg2+, Ca2+, or ethylenediaminetetraacetic acid. The process was pH dependent, with optimal activity occurring at pH 7. Sonic extract supernatants from group B and C meningococcal strains contained degrading properties, whereas similar extracts produced from Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Streptococcus pneumoniae type II failed to degrade the Gc2 polysaccharide.

Amino Acids↗