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The studies described were designed to examine the question of cross-reactivity between basic protein of myein and a basic protein common to many human tumours. The lymphocytes from guines-pigs injected with acid extracts of human cancer tissue showed significant (p < 0.01) transformation on exposure to basic protein of human myelin. Conversely lymphocytes from guinea-pigs injected with basic protein of human myelina showed significant (p <0.01) transformation on exposure to the acid extracts of human cancer tissue. Lymphocytes from control non-injected guinea-pigs did not transform on exposure to either antigen. These findings demonstrate immunological cross-reactivity in guinea-pigs between basic proteins of human myelin and of human cancer tissue using an assay system other than the macrophage electrophoretic migration hitherto used to show this effect in man. [ABSTRACT FROM AUTHOR]

An acid ether-soluble, strongly growth-stimulating substance revealed by the Avena coleoptile straight-growth test in methanol extracts from bean seedlings (Phaseolus vulgaris L.) was identified as indol-3yl-aspartic acid (IAAsp). Points of agreement between synthetic IAAsp and the investigated growth stimulator were indicated by chromatographic behavior, elution stimulator were indicated by chromatographic behavior, elution volume in gel filtration, mobility in paper electrophoresis, "colour reaction" with DMCA reagent, ability to form indol-3yl-acetic acid (IAA) and aspartic acid after hydrolysis and, finally, biological activity in the Avena test. Furthermore, some experiments demonstrated the occurrence of an inhibitor in extracts from light-grown tissue. This masked the stimulation of IAAsp in the Avena test when the extracts had been chromatographed in isopropanol: NH3 : H2O. A comparison of the levels of IAAsp between green and etiolated tissue did not reveal any distinct difference, demonstrating that the IAA conjugate IAAsp does not participate in the regulation of the photomorphogenesis. [ABSTRACT FROM AUTHOR]

Cell-free extracts of NH4-grown and N2-grown Clostridium pasteurianum were found to catalyze the oxidation of carbon monoxide to CO2 under strictly anaerobic conditions. Free formate was not an intermediate. FAD, FMN, methylene blue and viologen dyes were effective as electron acceptors, while NAD+, NADP+ or oxidized ferredoxin were ineffective. The reaction was routinely followed by measuring the reduction of methyl viologen with carbon monoxide photometrically. The rate of carbon monoxide oxidation followed simple Michaelis-Menten kinetics. 0.1-0.2 µmol carbon monoxide was oxidized by methyl viologen per min and mg soluble protein at pH 8.7. Half-maximal velocities were obtained with 5 µM carbon monoxide and 0.4 mM methyl viologen. The rate increased with increasing pH with an inflection point near pH 8.4. The carbon monoxide oxidizing activity was acid-labile (pH 4.5), precipitable with acids at pH 5 and sensitive to molecular oxygen. It was relatively stabile to heat. At 90 °C only 50% of the activity were destroyed within 15 min. Incubation of the extracts with cyanide (10 µM) or with methyl iodide (2.5 mM) resulted in a reversible loss of the carbon monoxide oxidizing activity. The rate and extent of inactivation by cyanide was decreased in the presence of carbon monoxide by a factor of 100 and 10, respectively. On the contrary, the rate of inactivation by methyl iodide was increased in the presence of carbon monoxide by a factor of 6. The activity of extracts inactivated by cyanide in the absence of carbon monoxide was partially restored by incubation of the extracts with carbon monoxide; the inactivation by methyl iodide was reversed by exposure of the extracts to the light of a projection lamp. These properties are taken to indicate that a vitamin B12 compound is probably involved in the catalysis of anaerobic carbon monoxide oxidation. [ABSTRACT FROM AUTHOR]

Pigeon droppings are known to constitute a highly potent source of antigens involved in the interstitial pulmonary disease known as 'pigeon breeder's lung'. Among the heterogeneous mixture of components in extracts of the droppings, a powerful enzyme was encountered which exhibits hydrolytic activity on proteins and synthetic ester substrates. Some characteristics of the enzyme in crude extracts have been established. Preliminary results indicate that human blood serum contains no inhibitors for the enzyme. [ABSTRACT FROM AUTHOR]

The effects were studied of extracts from the chrysophyte Ochromonas malhamensis on Staphylococcus aureus, Bacillus megaterium, Bacillus subtilis and Escherichia coli. The extracts contained three different antibiotically active substances, one of which was produced during the extraction. The other two had no effect on E. coli, but inhibited the growth of the three other bacteria. The present experiments show that one of the products increases its antibiotic activity when exposed to visible light, and that its activity is enhanced by boiling the extracts for 5 minutes. The other active substance is not affected by light, but shows increased activity after being boilt for 5 minutes. [ABSTRACT FROM AUTHOR]

The article focuses on biochemical research of aqueous extracts of dentin and dental enamel in relation to dental caries. It states that solutions of dental enamel had a pH value of 7.55 while dentin had a pH value of 7.85, with both extracts containing calcium, magnesium, potassium, and carbon dioxide-yielding materials. It mentions that protein levels of dentin was higher for non-carious teeth, while it was unclear if dental enamel contains soluble protein.

The percentage activation of the enzyme phosphorylase in extracts prepared from the epidermis of psoriatic lesions was found to be significantly lower than normal. This observation lends strong support to the concept of a reduced level of cyclic AMP in the lesion of this disease. [ABSTRACT FROM AUTHOR]

An optical technique for the assay of glyceraldehyde-3-phosphate dehydrogenase in skin extracts is described. This has been used to confirm the presence of this enzyme in mouse and human skin; the results obtained were in agreement with previous reports. Recovery experiments were carried out, using the pure enzyme, which indicated that the technique is valid in the presence of other interfering enzymes in the skin extract. [ABSTRACT FROM AUTHOR]

An optical technique for the assay of triosephosphate isomerase in skin extracts is described. This has been used to confirm the presence of this enzyme in mouse and human skin. Certain properties of the skin enzyme were examined; in its solubility, its pH curve, and the degree of inhibition by orthophosphate it was identical to triosephosphate isomerase preparations from other tissues. [ABSTRACT FROM AUTHOR]

The C.S.I.R.O. Division of Textile Physics is engaged in developing apparatus to increase the speed and accuracy of the yield-testing of greasy wool. One objective is to produce an automatic sample washer that will reduce the level of ash contents and alcohol extractables to some low, reproducible range, such as (0.5 ± 0.25%) of the greasy weight. This could lead to simplification of the present residuals-toting procedures. This paper describes the results of ash-content and ethanol-extract determinations on wool washed in experimental models of the new sample washer. It also describes experiments on careful laboratory-scouring of greasy wools and the effect of repeatedly scouring samples in machines. The following are the conclusions of this work. (i) By careful laboratory-scouring and mechanical-opening treatments, the ash content of all the merino and Corriedale wools tested could be reduced to below 0.1%. (ii) Other work, which showed that successive soxhlet treatments with ethanol continued to extract material from wool, has been confirmed. (iii) Successive machine-scouring of wool samples results in the attainment of equilibrium values of ash content and ethanol extractives. Typical values are 0.6% of the fibre weight for ash and 1% for ethanol extractives. (iv) Wool can absorb significant quantities of contaminants from ordinary tap water. (v) Excluding very burry wools, more than 95% of the ash contents and ethanol extracts obtained on a range of wools scoured in experimental models of the new sample washer were in the range (0.5 ± 0.25)% of the greasy weight. [ABSTRACT FROM AUTHOR]

1. The optimal pH value for the germination of ergot conidia is 4.8 in the presence of citric acid sodiumphosphate buffer. The growth of germ tubes is not as sensitive to pH as the germination percentage. 2. Ergot is not only able to live as a parasite on ears and nodes but also on internodes. 3. Germination of ergot conidia proceeds most satisfactorily at an osmotic pressure of 3.8 atm. 4. Extracts from different parts of the rye plant did not stimulate germination of ergot conidia. 5. Autoclaved extracts of different organs of the rye plant stimulated the growth of saprophytic cultures of ergot. The strongest effect was shown by extracts of ears. 6. Extracts of infected as well as of healthy rye stimulated the growth of saprophytic cultures of ergot. It was thus impossible to show by this method that in ergot as a result of infection substances injurious lo the parasite might be produced. 7. Saphophytic cultures grew well in cultures of rye embryos and on isolated wheat roots, but did not affect the host-plant. In such cultures it was not possible to detect the presence of alkaloids. [ABSTRACT FROM AUTHOR]

Tobacco pith tissue (Nicotiana tabacum, Variety Wisconsin no. 38) fails to grow on a modified White's nutrient agar medium, but undergoes marked enlargement resulting in a ca. tenfold increase in size of cells when optimal concentrations (ca. 2-3 mg./l.) of indoleacetic acid (IAA) are added to the medium. Higher and lower concentrations elicit less response, and 20 mg./I. IAA are often completely inhibitory. No cell divisions have been found in pure pith tissue either in the absence of added IAA or in connection with the cell enlargement in response to optimal concentrations of IAA even though there is an increase in nuclear material in the expanding cells. Cell divisions do occur, however, in pith tissues with attached vascular strands, or in severed pith tissue placed in contact with vascular tissues. The material active in inducing cell division is obtained in water extracts from vascular tissue and various plant products such as coconut milk or malt. It is diffusible through agar, but is not replaceable by traumatic acid. In its presence callus formation and organ differentiation as well as continued in vitro growth of the pith tissue are obtained. The marked differential growth responses of pith tissue to IAA and various plant extracts make it an excellent material for studies of metabolic and compositional changes associated specifically with the process of enlargement or proliferation of plant cells. [ABSTRACT FROM AUTHOR]

Thymus cells were examined for Ig by exposing them to purified anti-mouse L chain Ig labeled with 125I and examining, by bulk counting and radioautography, the amount of reagent bound. In addition, cell extracts were assayed for total Ig by a quantitative microprecipitin inhibition method. Most cells in thymus contained little Ig, but a minor subpopulation, varying in structure, did contain demonstrable Ig. This small proportion of cells (∼ 1%) appeared to be intrinsic to the thymus, and dose response data indicated that there was a hierarchy of Ig-positive cells. They were enriched in the cortisone-resistant fraction. Most were resistant to both anti-0 and an anti-B-anti-macrophage serum, leaving their identity in doubt. Some further properties, and suggestions as to the possible role of these cells in thymus, are discussed. [ABSTRACT FROM AUTHOR]

Effects of a number of spice extracts on streptococcal acid formation and enamel decalcification were tested in vitro. Of those which produced appreciable reductions, five were tested further to determine the nature of the effective components. Results demonstrated that both inorganic and organic factors play a part in reducing enamel solubility. [ABSTRACT FROM AUTHOR]

The purpose of this article was to determine whether the hypothesis that an osteogenic extract could stimulate bone repair in the healing of extraction wounds could be substantiated. Provided is a discussion of the problems and limitations in the control and evaluation of the selection of extraction wounds in human beings. Methods and materials and a discussion of the results are also provided.

ABSTRACT This research aim to study antibacterial activity of aqueous, alcoholic and methanolic extracts of aerial parts of Euphorbia helioscopia which belong to Euphorbiaceae family against some pathogenic bacteria. The results showed that aqueous extract was more active than alcoholic and methanolic extracts on growth of Staphylococcus aureus , Bacillus subtilis, Klebsiella pneumoniae, Escherichia coli , Pseudomonas aeruginosa and Salmonella typhi, comparing with Amoxycillin as a typical antibiotic. Methanolic extract showed no antibacterial activity against all bacteria studied except in Bacillus subtilis and Salmonella typhi. Minimum Inhibitory Concentration (MIC) and Minimum bactericidal concentration (MBC) value ranged from (25 ــ 200) mg/cm³, The antibacterial activity of the extracts are enhanced under acidic condition at pH = 2 and basic condition at pH = 10.

The article presents a study which examined the presence and role of carbonic anhydrase in the submaxillary gland extract of bovines. The role of carbonic anhydrase in the formation of dental calculus is mentioned. Results suggest that carbonic anhydrase is present in bovine submaxillary gland extract.