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prokaryotic cells; NAD (coenzyme); serine proteinases; chemical reactions; Human immunodeficiency virus 1; organic compounds; antibiotics; carbohydrates; boric acid; boron; inflammation; human health; chemical bonding; human nutrition; dietary minerals; purine nucleotides
... SUMMARY: An attempt has been made so to combine rapid acid-producing streptococci that on daily subculture the individual components in the mixture will remain present in even proportions. Some such combinations have been made, but frequently the proportions of the components alter until one culture becomes dominant. When one culture dominates rapidly this is due to the production of antibiotic fa ...
... SynopsisChopped alfalfa was treated with several antibiotics in concentration of from 1 to 200 parts per million before being ensiled in containers ranging from one quart to 40 tons capacity. In the first year, the initiation of fermentation was greatly delayed by antibiotic treatment, with ultimately much improved silage resulting; in 1955 and 1956, no differences between treated and untreated si ...
... Microbial products of an antibiotic nature produced in the rhizosphere may affect root growth and development. Twenty newer antibiotics have been tested to determine their activity in repressing elongation of roots of cucumber and growth of barley roots as measured by weight changes. Potency in repressing root elongation was found in most; 7 caused 50% repression at concentrations < 10 µg. per ml. ...
... The author reviews granulomas caused by chemical agents. Since there is insufficient knowledge with which to classify them fundamentally, they are classified practically as inflammation caused by endogenous and exogenous chemicals. Deposits of urate crystals, cutaneous calcinosis and cholesterin granulomas are endogenous. Exogenous inflammations in human medicine are the occupational diseases of t ...
... Physical, chemical, and plankton conditions were studied during two winters in three Colorado mountain lakes. Black Lake is mesotrophic, Pass Lake is highly oligotrophic, and Tea Lake is shallow, eutrophic, and pondlike. The lower waters of Black and Pass lakes absorb heat from the basin so that their winter temperatures are above 4.0°C and as high as 5.4°C. The substrate and bottom waters reach e ...
... Mice of two strains (a laboratory strain of white mouse and a fancy strain of coloured mouse) were fed on a proprietary cubed diet and were given to drink tap water, or water containing 26 mg per litre of one of the following antibiotics: chortetracycline hydrochloride, ampicillin, or tylosin tartrate. In the first experiment growing mice were given these diets for 8 weeks from 4 weeks of age. Amp ...
... The Soil microfungi in 36 northern Wisconsin conifer—hardwood forests have been surveyed by the dilution plate technique. Populations of 180 isolates from six sites in each forest examined, and frequency (sites of occurrence) was used to assess species importance. The 6,461 isolates represented 476 taxonomic entities, but only 87 (18%) of these occurred in three or more forests or had one frequenc ...
antibiotics; antifungal properties; screening; India
Abstract:
... A systematic screening of 170 different West Bengal plants was carried out to find antifungal antibiotics, using Aspergillus niger and Trichophyton rubrum as test organisms. From them, four plant species, viz. Curcuma zedoaria, C. aromatica, C. amada, and a Brassica sp. have been found to contain active antibiotic principles with strong inhibitory effects against both test organisms. ...
... The hide beetle Dermestes maculatus DeG. can be reared, and can complete its development on a semi-synthetic diet which is lipid-free, except for cholesterol. Any microbial source of lipids was eliminated by applying antibiotics, and the latter did not affect the insect growth. Fatty acid analysis indicates that D. maculatus neither synthesizes polyunsaturated fatly acids nur requires them for the ...
... A technique has been devised for maintaining the virulence of the endophyte of Alnus glutinosa L. during in vitro cultivation. Essential to the technique are the inclusion of an ether extract of Alnus roots and cycloheximide and chloramphenicol to the artificial medium. Using the devised medium, endophyte virulence has been maintained for 14 days whereas in the absence of the ether extract and ant ...
... This chapter focuses on nomenclature of antibiotic-producing fungi, and discusses the problem of nomenclature for fungi used in industrial fermentations. Only three groups of antibiotics are produced by fungi in the United States: cephalosporins, penicillins, and fumagillin. Fungi, including Myxomycetes, Phycomycetes, Ascomycetes, Basidiomycetes, Lichens, and Fungi Imperfecti, are covered by the I ...
... Feeding and choise experiments were performed with Phyllodecta laticollis using different extracts of Salix and Populus leaves. Specific polar phagostimulants are responsible for the choice of Populus by the insect. No effective deterrent was detected in Salix, and the physical texture of its leaves was shown to have little or no adverse effect on the insect's feeding. Various rearing experiments ...
... The proper disposal of organic wastes is one of our most pressing problems. Applications of these materials to agricultural land are becoming increasingly popular and information concerning nitrogen mineralization rates is necessary to ensure sufficient nitrogen for optimum plant growth and to prevent ground water contamination. The objectives of this study were to determine the nitrogen mineraliz ...
... Laminaria longicrucis De la Pylaie took up exogenous nitrate under both summer and winter conditions. During July and August no NO₃ ‐ was detected in the ambient water or in algal tissues although it was present in both in February. Discs (2.3 cm diam.) of thin blade tissue were incubated with NO₃ ‐ at four temperatures, with and without illumination. Similar values Jor NO₃ ‐ uptake were found for ...
... Disc‐diffusion, agar‐dilution and microdilution methods were compared for testing the antibiotic sensitivity of anaerobic bacteria. Eight antibiotics and 31 test organisms were used. There was a poor correlation between MIC values obtained by the agar‐dilution and microdilution procedures. The test organisms showed an apparently increased sensitivity to the antibiotics when tested by the agar‐dilu ...
... A 5-year-old cat with clinical colitis had histiocytic inflammation of colonic mucosa. Light and electron microscopy demonstrated bacilli, 0.7 × 3.0 micrometers, in various stages of degradation within macrophage cytoplasm. The disease is similar to histiocytic granulomatous bowel disease of other species. The cat responded to long-term treatment with antibiotics. ...
Ames test; antibiotics; body weight; males; mixed function oxidase; mortality; mutagenicity; mutagens; patulin; rats; synergism; unspecific monooxygenase
Abstract:
... The toxic interactions of patulin and rubratoxin B were studied in terms of either antagonistic or synergistic effects. A range of sublethal doses of test substance(s) (patulin, rubratoxin B or their combination) was administered to mature male rats. Mortality elicited by 0.25 mg of rubratoxin B/kg was prevented by the simultaneous administration of 1 mg of patulin/kg. Dose-related reductions in b ...
... Spores of Encephalitozoon cuniculi were exposed to various temperatures or to disinfectants, and their infectivity was then tested on monolayer cultures of canine kidney cells. The maximum survival time for spores suspended in medium 199 was 1 day at –20°C, 98 days at 4°C, 6 days at 22°C, and 2 days at 37°C. Only 2·5% survived 30 min at 56°C. Boiling for 5 min or autoclaving at 120°C for 10 min ki ...
... Intact soil cores were used to evaluate decomposition, NH₃ volatilization, N transformations, and metal movement in soils treated with sewage sludges and antibiotic processing wastes. Soil cores were leached monthly with water and incubated for 1 year. An insignificant amount (<1%) of the NH₄⁺-N applied was lost through NH₃ volatilization. The addition of wastes to five soils established that soil ...
... Developments and research in the present decade on the antibacterial finishing and disinfection of textiles are reviewed. Definitions and concepts of terms such as antimicrobial agent, antibacterial agent, disinfectant, and sanitizers are discussed from both a regulatory and scientific perspective. Quantitative tests for determining antibacterial activity of textiles usually involve sterilization ...
... Spontaneous renal disease in the pigtailed macaque was evaluated in a prospective study of 20 apparently healthy monkeys that were killed and a retrospective study of 674 monkeys that died of spontaneous disease. Many apparently normal pigtailed macaques have a mesangioproliferative glomerulonephritis of slight to moderate severity. Deposition of immunoglobulins, particularly IgM, was common in re ...
... The antibiotic activity of some compounds, and of plant extracts, was bioassayed by incorporating them in a wheat germ diet developed for rearing cotton spotted bollworm (Earias vittella F.). Acetone extract of square powder caused maximum mortality followed by gossypol, tannic acid, other tannins and anthocyanins. Hexane extract of bolls did not affect larval survival. Rutin, anthocyanins and eth ...
... Sodium borohydride in ethanol solution under mild conditions brings about the stepwise reduction of the 7‐keto and the 11‐keto groups of rutamycin and the oligomycins to the corresponding hydroxyl groups without further alterations of the macrocyclic lactone structure or other features of the molecule. The reduced compounds, as well as the parent antibiotics, inhibit the ADP‐dependent (state 3) re ...
... 2 cases of noma in cotton topped marmosets (Saguinus oedipus) are reported. The condition did not respond to antibiotic therapy, but was successfully treated in one animal by local application of ethacridine lactate. ...
... Fermentation residues are formed during the production of antibiotics and organic acids. If these residues are to be applied to agricultural land, information concerning nitrogen availability, crop response, and possible toxicity is needed so that appropriate application rates can be determined. Wastes were applied to an Enfield silt loam soil (coarse-silty over sandy-skeletal, mixed mesic, Typic ...
... Four blind duplicate milk samples containing β-lactam residues were analyzed by 149 analysts at 47 laboratories. Four official variations were used: (a) antibiotic 4 (A4) agar and 55°C incubation, (b) A4 agar and 64°C incubation, (c) PM indicator (PMI) agar and 55°C incubation, and (d) PMI agar and 64°C incubation. A β-lactam concentration of 0.008 IU/ml was detectable 100% of the time by variatio ...
... Supernatant fractions from different organs of rat and beef origin were tested for their effect on the mutagenic activity of N-methyl-N′-nitro-N-Nitrosoguanidine (MNNG), using Salmonella typhimurium tester strain (TA 1535). At equal protein concentrations their effects were quite different. Both beef and rat liver supernatant fluids (1.7 – 3.4 mg of protein per plate) completely inhibited the muta ...
... Kinetic analyses were performed to characterize the conversion of 1-aminocyclopropane-1-carboxylic acid (ACC) to ethylene (C₂H₄) in soils. Application of three linear transformations of the Michaelis-Menten equation indicated that the Kₘ values varied slightly among soils, but were similar in magnitude. By using the Lineweaver-Burk plot, the Kₘ values in three soils ranged from 2.7 to 6.1 (avg = 4 ...
Actinobacteria; Quartzipsamments; antibiotics; electron microscopy; gamma radiation; models; relative humidity; sand; sandy soils; temperature; water repellent soils; Florida
Abstract:
... The degree of resistance to water penetration of diverse water repellent soils was found to be controlled by their moisture states. Repellency was found to increase sharply when samples were incubated at 100% relative humidity and to decline when wetted or when incubated at humidities < 90%. A soil which was nonwater-repellent in the field did not become repellent at 100% relative humidity. A Flor ...
... Four antibiotic-resistance plasmids isolated from thermophilic bacilli were characterized in detail. Three tetracycline-resistance (Tcʳ) plasmids were designated as pTHT9 (7.7 kilobases (kb)), pTHT15 (4.5 kb) and pTHT22 (8.4 kb). From the results of restriction endonuclease analysis and the subsequent Southern hybridization, these were found to possess extensive genetic homology in the regions tha ...
... An aphid rate of increase index was used as a comparative measure of antibiotic resistance to Aphis fabae Scopoli (Homoptera: Aphididae) in five faba bean cultivars. The index was measured over a range of bioassays in laboratory and field, with seedlings and older plants, with three different previous aphid hosts and with two different aphid clones. Antixenotic resistance was measured by recording ...