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PubMed1968

The purification and concentration of hog cholear virus with electron micrographs (a preliminary note).

Cell-cultured hog cholera virus was partially purified by chromatography on pulverized magnetic ferric oxide. Infectivity yields of 50 to 100% were obtained with a 90 to 95% reduction in extraneous organic nitrogen. Concentration and further purification of infectious virus were achieved by rate-zonal and isopycnic ultra-centrifugations in buffered cesium chloride. Density determinations obtained from the isopycnic experiments indicate a buoyant density of 1.14-1.15 gm/ml for the strain of virus used. Electron microscopy of negatively stained samples of concentrated infective virus from one isopycnic experiment revealed 40- to 40-mmicro virus-like particles and a large number of 12- to 15 mmicro entities. The 40- to 50-mmicro particles were surrounded by a poorly defined, asymmetrically arranged sac-like membrane or appendage. It is suggested that the images of the 40- to 50-mmicro particles represent the infective virion of hog cholera virus.

Animals↗
PubMed1975

The human leukocyte test system. III. Premature chromosome condensation from chemically and x-ray induced micronuclei.

Premature chromosome condensation (PCC) was induced in human leukocytes in vitro by a bifunctional alkylating agent 2,5-bis-(methoxyethoxy)-3,6-bis-ethylene-imino-p-benzoquinone (A 139), bleomycin and X-rays. Analysis shows that PCC originates from micronuclei that have been slowed down in their cell cycles in respect to the main nuclei. The mitosing chromatin of the main nuclei induced PCC in the associated micronuclei. Morphologically the PCC was mostly of the S-phase type with the chromatin exhibiting a more or less pulverized appearance; in some experiments this was verified by incorporation of (3H) thymidine (TdR). In a few cases the PCC looked like G2-phase PCC with ladder-like chromosomes. GI-phase PCC was not found. PCC of the type described in this work may be used as an indicator of induced lagging of chromatin that can be the result of chromosomal aberrations or of nondisjunction.

Alkylating Agents↗
PubMed1970

Effect of cellulose in the diet on the recovery of dietary plant sterols from the feces.

In one normal subject, J.S., fed several formula diets in a sterol balance study, only 25-58% of the ingested plant sterols were recovered from the stool. The dietary plant sterols were completely recovered from the stools of five other men. Plant sterol recovery was complete in all men when a diet of mixed general foods was consumed. Since the chief differences in composition of the formula and the diet of mixed general foods were related to the different contents of cellulose and lactose, these components were added to the formula diet of J.S., and plant sterol balance studies were then carried out. The addition of fresh celery or pulverized cellulose to the formula diet partially corrected the usual fecal loss of plant sterols (80% being recovered). Lactose in the formula was only slightly corrective. However, the addition of both cellulose and lactose led to complete recovery of the ingested plant sterols in the feces. Bacterial cultures of stools were incubated with added cholesterol-4-(14)C, and a linear relationship between losses of sterol during balance studies and in vitro incubations was observed; that is, a considerable loss of the labeled cholesterol from cultures after the formula diet, but not after the diet of mixed general foods. This in vitro loss was also corrected by the addition of cellulose and lactose to the formula diet. The loss of the sterol nucleus in the intestinal tract may occur at times because of the lack of certain dietary constituents. It is hypothesized that the metabolism of intestinal tract bacteria is altered when certain constituents are not present in the diet, and that these bacteria may then degrade the sterol nucleus.

Carbon Isotopes↗
PubMedDate not supplied

Comparison of bioavailability of two dipyridamole formulations.

The experiment carried out on 6 volunteers shows a better bioavailability of a 75 mg single oral dose of Persantin (Boehringer) than of the same dose of Curantyl (Germed). The difference is due to the manner in which the dragées are manufactured: the bioavailability of both preparations was the same when the dragées were pulverized before oral administration.

Adult↗
PubMed1977

[Effect of carbon disulfide on peripheral blood leukocytes. I. Effect of carbon disulfide on in vitro chromosome structure and division capability of leukocytes in man].

The peripheral blood leukocytes in normal subjects were cultured according to Moorhead with addition of CS2 (0,75 microliter/ml of culture). It has been found that CS2 decreases the mitotic index, and in some cultures inhibits totally the cell division. Moreover, it causes structural disturbances of chromosomes being of pre- and postreplicative character as well as their viscous degeneration, lesser spiralization and sometimes pulverization. The presence of greater amount of erythrocytes of the donor's blood in the culture markedly diminished the intensity of these changes.

Adolescent↗
PubMed1980

[Preparation of hard crown and bridge resin without PMMA powder (III) (author's transl)].

We have been studying hard crown and bridge resins. Mixtures of several polyfunctional monomers and a composite filler finely pulverized, prepared by polymerization of trimethylolpropane trimethacrylate in the presence of hydrophobic colloidal silica, were polymerized and their mechanical properties were studied. They were excellent and a sample from 2.6 E.UDMA comonomer was the best among them. The new filler possessed better affinity with matrices than composite fillers reported previously, presumably due to the reactivity with matrices. Introduction of this new filler into the hard crown and bridge resin preparation must improved the resins remarkably.

Crowns↗
PubMedDate not supplied

Lung parenchyma response of rats stimulated with living pneumococci by respiratory way. A histologic, histochemical and electron microscopic study.

The pulmonary intralobular connective tissue of albino rats stimulated by a pulverized suspension of living pneumococci is the site of an abundant cell proliferation and pyronine-plasma cell reaction, having as molecular substratum enhanced activity of Alk-Ph-ase, ATP-ase, SDH-ase and LDH-ase. Cells in varying degree of plasmacytic differentiation were evidenced electron microscopically at alveolar wall level.

Animals↗
PubMed1984

[Combined endoscopic-endographic diagnosis of the larynx and trachea with contrast medium powders].

The endographic examination by means of pulverized contrast media such as tantalum or visotrast acid has proved to be appropriate in laryngotracheobronchial diseases as a simple and safe, endoscopy-complementing method. It gives diagnostic radiological information in addition to endoscopic, orthograde evaluation by the frontal and sagittal image of the organ in which details of the structure and alterations can be detected. In 170 different examinations of the organ no threatening side-effects could be observed, even not in cases of remarkably obstructive changes. When giving contrast media containing iodine any known iodine allergies should be avoided, despite the water-insolubility of the complex iodine compound.

Diatrizoate↗
PubMed1984

Relationship between the induction of chromosome damage and cytotoxicity for amsacrine and congeners.

The antitumor drug amsacrine causes chromosomal aberrations both in cultured cells (L1210 murine leukemia and HeLa cells) and in vivo (L1210 leukemia). The proportions of different types of aberrations, mainly chromatid gaps, chromatid exchanges, and acentric chromosome fragments, are similar in both the in vivo and in vitro experiments. A small proportion of cells, particularly after drug exposure for 24 hours, show extensively damaged or pulverized chromosomes. In in vitro experiments using HeLa cells and amsacrine together with two analogs of amsacrine with differing cytotoxic activity, an inverse relationship between the frequency of chromosomal aberrations and cell survival has been demonstrated. The results are consistent with the proposal that for this class of drugs, the induction of chromosomal aberrations, both in vivo and in vitro, leads to cell death.

Aminoacridines↗
PubMed1983

A food pelleter for experimental diets for rats.

Food pellets for an experimental diet for laboratory rats were produced for long-term nephrotoxicity study using a modified, commercially available pasta machine. This method eliminated the disadvantages of powdered diets and provided the advantages of pelleted diets at low production cost. A commercially available, pelleted diet was pulverized, the test agent and water added, and the mixture repelletized. No special feeding equipment was required because the repelletized diet was fed in standard lid-type feeders. It was not necessary to sterilize the diet.

Animal Feed↗
PubMed1983

[Identification of crystalline phases and various metal content of fibrous minerals (Polish asbestos) found in nickel ore deposits].

Nickel ore deposits near Szklary in Lower Silesia are accompanied by minerals of clearly fibrous structure ("Polish asbestos"). The pulverization process of those minerals yields particles resembling fibres. Basing on the diffractometric characteristics and absorptive spectra analysis in infrared, crystalline phases were identified in five dust samples of those minerals. The major crystalline phases were found to be: anthophyllite (samples 1, 2, 3), quartz (samples 2, 3, 5) and antigorite (samples 4 and 5). Tests on X-ray spectrometer SPARK-1 indicated that all the samples contained ferrum (1-2%), nickel (0,08-0,15%), copper (below 0,005%), in one sample the content of zinc amounted to 0.006%, in the other the content of zinc and chromium was lower than their detectability limit. Air dustiness in the nickel ore mine and nickel ore processing plant may result in serious diseases in those inhaling the dust. The pollution of air, water and soil in the mine environs cannot be neglected, either.

Asbestos↗
PubMed1983

Some electron microscopy characteristics of lung immune response in the rats stimulated by respiratory and parenteral ways with pneumococcal suspensions.

Conventional albino rats of either sexes, weighing about 100 grams, were stimulated, one group by inhalation of pulverized suspensions of living type III pneumococci, in 6 exposures, and the second group, by 5 intramusculary injections, one a week, of 0,1 ml, emulision of killed germs, in complete Freund's adjuvant submitted after a week free interval to the inhalation of aerosolized living pneumococci. The tissue fragments sampled at two and respective five weeks after the beginning of the experiment, from central and peripherical sites of lungs, inclusively from a control group, were fixed in glutaraldehide-osmic acid and prepared for electron-microscopical examination. In the thickened, densely cellular alveolar walls there are numerous mature plasma cells, intermediate elements between reticular septal cells and plasmablast and also histiocytic cells which phagocytic inclusions and shape suggests their movement in the interalveolar septa. The swollen free alveolar macrophages contain an increased number of lysosomes and ribosomes. The hyperplastic granular pneumocytes possess enlarged cytosomes excreting osmiophilic material in the air spaces. There are discussed the problems of local plasma cell differentiation, alveolar macrophage physiology and transparietal migration of histiocytes.

Aerosols↗
PubMed1984

Chromosome breakage induced by thymidylate stress in thymidylate synthase-negative mutants of mouse FM3A cells.

In thymidylate synthase-negative mutants of mouse FM3A cells, thymidine starvation rapidly decreased mitotic activity and resulted in cell death (thymineless death). When the thymidine starvation was reversed by an addition of thymidine, mitotic activity was recovered, but the majority of mitotic cells exhibited extensive chromosome aberrations, including chromatid breaks, chromatid exchanges, and pulverizations. Autoradiographic examination revealed that chromosome instability was induced only in cells arrested in the S phase during thymidine starvation. Furthermore, the most sensitive sites to the chromosome-damaging effect appeared to be sites which had replicated just prior to thymidine starvation. During thymidine starvation, cells at other stages in the cell cycle were accumulated at the G1-S boundary, and they were insensitive to the chromosome-damaging effect. Thymidine starvation was also found to be recombinagenic. Complete removal from the medium of a thymidine analogue, 5-bromo-2'-deoxyuridine, resulted in a dramatic increase in the frequency of sister chromatid exchanges. These results support the view that thymidine starvation in mammalian cells results in thymineless death via induction of DNA double-strand breaks, leading to chromosome fragmentation as well as rearrangements in the cells synthesizing DNA.

Animals↗
PubMed1978

[Constitutional stereotyped gap in human chromosomes (author's transl)].

The stereotyped break with gap of a chromosomal variant is rarely observed. This anomaly is transmitted according to autosomal dominant rule. The distal part of the broken chromosome may either be still bound to the sister chromatid through mitotic non-disjunction, forming a triradial figure, or take a moniliform and pulverized appearance, evoking premature chromosome condensation.

Cells, Cultured↗
PubMed1981

Serum reserve cholesterol binding capacity (SRCBC): the relative importance of different lipoprotein classes.

Findings by several authors have motivated studies in our laboratory on the relationship between HDL and "serum reserve cholesterol binding capacity" (SRCBC). We found that incubation for 25 hours at 37 degrees C provided optimal conditions for uptake and saturation when 14 mg sonicated and pulverized cholesterol was added to 1 ml serum. Upon separation of serum to which 14C labelled cholesterol had been added, into lipoprotein classes, a higher cpm:protein ratio than expected (from the free cholesterol:protein ratio, assuming isotope exchange exclusively) was found in LDL and the HDL fraction. In a second series of experiments, the different lipoprotein classes were separated prior to addition of 14C-cholesterol. The highest capacity for uptake of labelled cholesterol was found in the HDL fraction. The major part of the 14C-cholesterol appeared in the LDL density area when this HDL fraction was subjected to repeated ultracentrifugation. This suggested that the uptake of added cholesterol by HDL had led to the formation of an altered particle with density characteristics similar to those of LDL particles. This was confirmed by the demonstration of a "new" particle which contained apoA-I, apoA-II, and apoE, but no apoB or Lp(a) antigen. Its electrophoretic mobility was similar to that of HDL. Electron microscopy revealed that this particle is larger than normal HDL. The findings suggest that a sub-population of HDL molecules may be responsible for serum binding of added excess cholesterol.

Apolipoprotein A-I↗
PubMed1982

[Effect of preventive treatment of acute hypomagnesemia on the biochemical and morphological indicators in cows during the grazing period].

From each of 2 tetanic herds and 1 control herd 20 cows were randomly selected to determine serum levels of Mg, Ca, inorganic P, Na, K, Cl-, total protein, urea, GOT-activity and blood-glucose level. In rumen fluid the number of ciliates, ammonia, level, pH and total acidity were examined. Haematological investigations were carried out. Moreover dry matter and height of the herbage were measured, and meteorological measurements were utilized. The investigations were carried out before grazing and than on the 4th, 8th, 12th, and 16th day of grazing. Symptoms of metabolic disturbances and alcalic indigestion were found to be more distinct in the tetanic herds than in control herd. The method of MgO-pulverization on pastures was found to be useless. On the other hand, MgO-food-supplementation according to generally known methods was found to be of high usefulness. MgO-treatment at a dose of 50 g per cow and day in a period of 14 days before grazing effectively prevented the outbreak of hypomagnesaemia in spite of such tetanogenic factors as unfavourable weather, insufficience of dry matter in the herbage and subclinical alcalic indigestion with disturbed nitrogen metabolism.

Animal Feed↗
PubMed1982

Carcinogenic and mutagenic activity of an alkaloidal extract of Senecio nemorensis ssp. fuchsii.

The alkaloidal residue obtained after extraction of dried and pulverized Senecio nemorensis ssp. fuchsii contains two pyrrolizidine alkaloids, i.e. fuchsisenecionine and senecionine. In a chronic experiment doses of 8 mg/kg and 40 mg/kg b.w. of the alkaloidal extract were given five times a week by gavage to male and female Sprague-Dawley rats. The study was terminated after 114 weeks. Repeated serum analysis demonstrated a dose-related elevation of serum glutamic oxalacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT) and alkaline phosphatase (AP). Beside its hepatotoxic effect, the treatment proved to be hepatocarcinogenic, showing female rats to be more sensitive than males. Tumors diagnosed were of hepatocellular and angiogenic origin. In age-adjusted analysis the occurrence of these neoplasms revealed a clear dose-related trend (p less than 0.00005). In the in-vitro mutagenicity test system with V 79 Chinese hamster cells, the alkaloidal extract exerted a weak but dose-related mutagenic activity. Under the conditions used the alkaloidal extract of Senecio nemorensis ssp. fuchsii is a genotoxic carcinogen.

Alkaline Phosphatase↗
PubMed1980

Kinetics of nitrosamine formation in mice following oral administration of trace-level precursors.

Groups of 3-5 Swiss CD1 mice were gavaged with aqueous solutions of sodium nitrite (250 micrograms), followed immediately by morpholine (5 micrograms) or dimethylamine (250 micrograms). At subsequent intervals, up to 30-60 min, mice were frozen, pulverized in liquid nitrogen and extracted with methylene chloride. Volatile nitrosamines were then quantitatively determined using a Thermal Energy Analyzer, interfaced to GC or HPLC. Biosynthesis of both N-nitrosodimethylamine (NDMA) and N-nitrosomorpholine (NMOR) showed a time-dependent increase for 3 and 9 min, respectively, followed by a steady decline. Levels of NDMA and NMOR were generally less than 0.1 ng/g in control mice gavaged with amine or nitrite alone. Zero-time recovery of NDMA and NMOR ranged from 50-70% and 70-90%, respectively. Biosynthesis of NDMA and NMOR was inhibited by prior administration of ascorbic acid, sodium ascorbate or ammonium sulfamate.

Administration, Oral↗