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Antimicrobial properties of some West African medicinal plants iv. Antimicrobial activity of xylopic acid and other constituente of the fruits of Xylopia aethiopica (Annonaceae).

Xylopic acid and four other isolates from the fresh ripe fruits of Xylopia aethiopica a common ingredient in several Ghanaian folklore medicines and foods, have been examined for antimicrobial activity against five micro-organisms, Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. Xylopic acid and two other diterpene isolates were found to have antimicrobial properties.

Anti-Bacterial Agents↗

PubMed1977

[Influence of N-serve on mineral nitrogen forms and microorganisms of the soil (author's transl)].

In a model experiment with soil, 2 stages of nitrogen (without additional N and with 200 kg N/ha in the form of ammonia) and 3 N-Serve stages (without inhibitor and with 0.25 per cent and 1 per cent of inhibitor, relative to 200 kg of N/ha) were followed up over a period of 3 and 6 weeks, respectively, with respect to the dynamics of the nitrification process, the saprophytic soil microorganisms, and the autotrophic nitrifiers. In a second experiment, the ammonia form of nitrogen was substituted by the nitrate and nitrite form, respectively. No serious influence on the heterotrophic soil micro-organisms could be detected in any experimental variant; N-Serve was slightly stimulating, the autotrophic nitrifiers were noticeably depressed by N-Serve. The nitrification process could clearly be proved after 3 weeks already; by N-Serve it was remarkably delayed. Nitrite that had been added to the soil was scarcely transformed into nitrate, whereas it was somewhat more ammonified. The high loss of nitrogen in the nitrite variant cannot be caused by denitrification alone. When nitrate was used, the nitrification was not delayed.

Ammonia↗

PubMed1978

[Effect of gum guar in diet on nitrogen balance, protein metabolism and food transit time in rats].

The addition of 5% gum guar to a diet containing 10% casein did not change the overall N retention of young rats but induced a significant shift in the N excretion from urine to feces, resulting in a markedly decreased apparent protein digestibility. The increase in total fecal dry matter over control values accounted for only 30% of the ingested gum guar implying that 70% was absorbed, possibly after being degraded by intestinal micro-organisms. The elimination of 14C activity following oral application of 14C protein indicated an accelerated turnover of amino acids during the first 3 h. After 25 h no difference between experimental and control animals was evident with respect to 14C activity remaining in the carcass. The transit time of food, as determined by neutron activation analysis of an Ytterbium marker, was somewhat decreased in the presence of gum guar.

Amino Acids↗

PubMed1978

Studies on gallium accumulation in inflammatory lesions: II. Uptake by Staphylococcus aureus: concise communication.

Gallium-67 was demonstrated to be taken up in significant amounts by a number of common micro-organisms. The mechanism of gallium-67 uptake was studied in S. aureus. It is found to involve two separate processes. One is insensitive to temperature or metabolic inhibitors, and is not inhibited by a high concentration of nonradioactive gallium. This process probably operates through nonspecific binding of Ga-67 to components of S. aureus. The second process is not inhibited by metabolic inhibitors either, but it is temperature-sensitive and is inhibited by high concentrations of stable gallium. This component of the Ga-67 uptake is most likely due to a carrier-mediated transport system (facilitated transfer).

Antimetabolites↗

PubMed1978

[Studies on the Microbiological Quality of Mammary Gland Tissues (author's transl)].

During the period from August to December 1976, 239 bovine udders were examined for their microbiological quality. Counts were made of the total number of aerobes, anaerobes, Enterobacteriaceae, coliform micro-organisms and staphylococci positive for coagulas and DNA-ase. The udders were examined for the presence or absence of Salmonella, E. coli and haemolytic streptococci. In addition, the Enterobacteriaceae were identified. The udders examined were from animals brought up for slaughter from all over the country. The studies were designed to examine whether udders are suited as raw material for products to be consumed by human individuals. The number of pathogenic bacteria isolated was found to be considerable and the average bacterial counts were rather high. The studies showed that the bacterial content of mammary-gland tissues has an adverse effect on the quality of raw meats made from these tissues so that they are not aceptable from the point of view of public health. Even when they are used as raw material for heated products, the risk of food poisoning caused by toxin produced by staphylococci cannot be entirely ruled out.

Animals↗

PubMed1978

Secretory antibody responses in axenic mice to perorally administered Staphylococcus aureus.

Topical oral immunization of axenic mice with non-replicating Staphylococcus aureus resulted in the production of both serum and salivary agglutinins. A latent period of approximately 5 days was noted before salivary antibodies were detected against both a carbohydrate (ChoA) and a protein (PrA) antigen isolated from this micro-organism. The local response to ChoA exhibited a linear increase until day 9 when the reciprocal titres reached a plateau [32 (16--64)]. Salivary antibodies to PrA peaked by day 13 at a mean reciprocal titre of 60 (32--128). The agglutinin response in saliva was found to be initially IgG; however, by day 9 of a 14-day-immunization regimen, IgA became the predominant class of exocrine anti-S. aureus antibodies. The serum agglutinin response followed that found in saliva by approximately 2--4 days. By day 14, all sera (6/6) contained PrA agglutinins, while 4/6 sera agglutinated sheep erythrocytes coated with ChoA. Serum antibodies to ChoA were exclusively IgM, in contrast to IgM and IgA agglutinins elicited by PrA. Absorption studies provided evidence of a specific local and systemic immune response to both ChoA and PrA antigens of perorally administered S. aureus.

Agglutinins↗

PubMed1978

Infective endocarditis complicating congenital heart disease.

The pathological alterations in 34 patients with infective endocarditis complicating congenital heart defects were studied. The overall incidence of infective endocarditis in patients with major congenital cardiac defects was 4,7%. Most patients were under 31 years of age and males predominated. The infection was associated with Fallot's tetralogy in 10 patients (17%), ventricular septal defect in 7 (4%), bicuspid aortic valve in 7 (16%), coarctation of the aorta in 6 (8%), atrial septal defects in 2 (1%), and patent ductus arteriosus and pulmonary artery branch stenosis in 1 patient each. The causative micro-organisms were successfully cultured from only 29% of patients. Fourteen of the 34 patients had infection of an associated 'jet' lesion. Patients with isolated ventricular septal defect showed tricuspid valve endocarditis more commonly than did patients with Fallot's tetralogy. The infection had been missed clinically in 34,8% of patients, 50% of whom were aged 3 years or younger.

Adolescent↗

PubMed1978

[Intermediate moisture foods and water activity determination].

In order to define the concept of Intermediate Moisture Foods (IMF) some ideas concerning the water bonding state in foods are reminded: water molecules properties, polar groups of hydrophilic macromolecules, activity of water (aw); sorption and desorption isothermal curves. Between dried products (solids with friable and breakable texture) anv very hydrated products (meat or fresh fruits for example), the IMF are characterized by their high aw (from 0.65 to 0.90) and their generally soft texture. Some typical examples of traditional and new IMF are then given. The IMF alterations are induced by chemical (oxydation) or biochemical (enzyme), biological (micro-organisms) or biophysical (water migration) causes, each of them being controlled by aw, temperature, pH, and other parameters. IMF technology consists generally to formulate products, the aw of which are less than 0.9, with aw depressors. Precise measurements of aw are then one of the most important mean for controlling fabrication, the direct computation being generally impossible. A manometric reference method for determination of aw is described; it consists to measure directly the equilibrium water vapor pressure. This method is preferable to a dew point determination. Some practical methods are reported, in connection with their accuracy and facilities of use.

Food Analysis↗

PubMed1977

Microbial secondary metabolites with potential use in cancer treatment. (Plasmid involvement in biosynthesis and compounds.

Antibiotics and small molecular enzyme inhibitors produced by micro-organisms are microbial secondary metabolites which have no obvious function in the growth of microorganisms. Involvement of plasmids in their biosyntheses has been studied and the structure of the microbial world where various compounds with widely varying structures have been found has been shown to be due to the presence of a great variety of plasmids. On the basis of this structure of microbial world, the author has found the microbial products which have various activities useful in treatment of cancer or in suppression of carcinogenesis. In this paper, the author reviewed his following studies: the plasmid involvement in biosyntheses of bioactive microbial secondary metabolites; the mechanism of therapeutic effect of bleomycin, and the development of useful analogs and derivatives of bleomycin and anthracyclic antibiotics; the screening method to find compounds affecting immune system, and the action of bestatin in enhancing delayed-type hypersensitivity and therapeutic effects of anticancer agents; enzyme inhibitors with potential utility in treatment or prevention of cancer.

3',5'-Cyclic-AMP Phosphodiesterases↗

PubMed1978

Microbial degradation of diethanolamine and related compounds.

Thirteen diethanolamine compounds were tested for their biodegradability employing (1) a bacterium selectively isolated from an industral cutting fluid, and (2) an acclimatized sewage population obtained from a domestic waste treatment plant. Pure culture growth and biochemical oxygen demand studies with the isolate showed that only diethanolamine, methyl-diethanolamine, triethanolamine, and laurylsulphate-diethanolamine were degradable. Biochemical oxygen demand techniques using the acclimatized sewage micro-organisms as seed yielded similar results with only diethanolamine, methyl-diethanolamine, triethanolamine, and laurylsulphate-diethanolamine being oxidized to any meaningful extent. Cyclohexyldiethanolamine, phenyl-diethanolamine, and m-tolyl-diethanolamine had oxygen demands of less than 1% of their theoretically calculated values, while ethyl-diethanolamine and benzyl-diethanolamine accounted for 3.6 and 2.3% of their theoretical values respectively. In both systems employed substitution of the tertiary hydrogen of the amine group with isopropyl, 3-aminopropyl, n-butyl, or t-butyl resulted in biologically recalcitrant compounds.

Bacteria↗

PubMed1976

Design of metabolic and enzymic machinery to fit lifestyle and environment.

Biochemical theory, spectacular as its growth has been in the last half-century, finds its experimental basis in a remarkably few organisms. The rat, the ox, the pig, the hen plus a few micro-organisms consitute the primary source of biochemistry's experimental material, while, by contrast, modern systematics estimates a bewildering and often overlooked diversity of over 10(6) animal species. As a result of this highly limited 'sampling' of nature, classical biochemistry has supplied an equally limited insight into how far biochemical mechanisms can be extended or adapted for (1) allowing an organism's exploitation of its environment and (2) accommodating environmental change. The situation has improved in more recent years, so that it is now possible to decipher at least the broad strategic outlines of biochemical adaptation to the environment. This essay focuses particular attention on the influence of O2 availability on muscle metabolic organization and control. By drawing examples of muscle metabolism spanning a range from obligate-anaerobic to obligate-aerobic organization, it is possible to demonstrate that certain kinds of metabolic features are highly conserved, whereas others are changed time and time again, in different combinations and permutations. The latter properties constitute the 'raw material' for adapting metabolism to specific O2 regimes, and include (1) the kinds and amounts of enzymes present in muscle, (2) the fine regulatory circuitry allowing for controlled transition from low to high work loads and (3) compensation mechanisms for the adjustment of enzyme reactions with respect to such external parameters as temperature, pressure, salinity and so forth. Within the inescapable limitations of phylogenetic origins and the time available for responding to specific environmental conditions, adequate adaptations of the fundamental design of muscle metabolism have evolved to exploit environments differing greatly in O2 availability and to accommodate a wide range of muscle functions.

Acetylcholinesterase↗

PubMed1976

Peripheral dissemination of bacteria in contaminated wounds; role of devitalized tissue: evaluation of therapeutic measures.

The role of available therapeutic agents in the management of infection has long been a continuing source of debate. This study assessed the rapidity of lateral dissemination of three common pyogenic organisms from wounds. The Streptococcus spreads peripherally with greater speed than the Staphylococcus or E. coli. Appraisal of the role and effectiveness of jet wound irrigation, debridement, and penicillin provides firm evidence that, of these three therapeutic agents, the only one that can control bacterial proliferation in a contaminated wound is the antibiotic. The primary role of energized jet irrigation is to remove clots and wound debris. The specific function of debridement is removal of devitalized tissue, in which role it has no effective competitor. These studies demonstrate that devitalized tissue in a contaminated wound quickens the rapidity of peripheral spread of all three micro-organisms. Systemic penicillin plus saline irrigation is the most effective therapeutic measure at both the second and fourth postinoculation hours in nondevitalized contaminated wounds. Debridement proved to be the most effective therapeutic device at the second, fourth, and sixth postinoculation hours in devitalized wounds.

Animals↗

PubMed1976

[Comparative clinical and experimental studies of various denture cleansers. 2. Testing of antimicrobial efficiency].

Agar diffusion plate tests were performed on five strains of micro-organisms to characterize the disinfecting properties of nine denture cleaners. Furthermore, the liberation of oxygen was determined as a function of time, and the course of pH variation of the various cleaning solutions was studied. The highest oxygen concentrations and the best antimicrobic activities were achieved by the preparations Eladent G and T.

Bacteria↗

PubMed1976

Numerical immunotaxonomy of Leishmania. I. Differentiation of four strains of Leishmania by serological tests.

This paper describes the application of numerical methods to the arrangement of four leishmanial strains according to their reactivity and cross-reactivity in tests of parasite agglutination, indirect immunofluorescence and passive cutaneous anaphylaxis with antisera prepared by immunization or infection of rabbits, guinea-pigs and mice. Using corresponding pools of animal sera as test 'reagents' the antigenic reactivity of the four leishmanial strains (L. enriettii, L. tropica major, L. aethiopica and L. mexicana amazonensis) was scaled by reference to end-point serum titres; and antigenic relationships between individual strain pairs were expressed as mean similarity coefficients, giving equal weight to the results of the different serological tests. Overall analysis of the results revealed that L. mexicana amazonensis and L. tropica major were the two most closely related strains, clustering with an overall similarity coefficient of 89%, whereas coefficients of similarity between other strain combinations fell between 75 and 80%. Although different sera had different discriminatory capacity for the leishmanial strains, two combinations of serum reagent and test system yielded relationships between the four strains that most closely approximated to the overall values. These were: (a) immunofluorescence tests with mouse antisera; and (b) agglutination tests with selected rabbit antisera. The results illustrate the use of a number of immunological parameters in relating micro-organisms of a given genus, and reveal a serological classification of the four leishmanial strains at variance with their geographical origin.

Agglutination Tests↗

PubMed1976

Bladder defense mechanism.

In order for micro-organisms to infect the urinary tract they must adhere to the vesical mucosa so that they remain after voiding. Experiments in our laboratory demonstrated that the bladder has a self-protective mechanism capable of preventing bacterial adherence to the surface. Histochemical staining demonstrated that this substance is a mucopolysaccharide. Treatment of the mucosa with acid disrupted the protective layer and resulted in a 20 to 100-fold increase in bacterial adherence. Within 24 hours this layer reappeared and binding was again reduced to normal. This phenomenon was not related to microbial species or metabolic activity.

Adhesiveness↗

PubMed1975

[Penicillin V potassium in tonsillar tissue and serum (author's transl)].

1.2 mega U Penicillin V potassium was given to 20 patients 2 hours (group 1) and another 19 patients 3 hours (group 2) before tonsillectomy. After the operation biological determinations of the levels of active principle were made from tonsillar tissue and serum with statistical evaluation of the results (Spearman's rank correlation). There was a significant connection between the serum and tonsillar tissue concentrations (in children and adults) in both groups. The level of the active principle in group 2 was only slightly lower than in group 1. Many of the micro-organisms responsible for tonsillitis can be influenced by the concentrations found here, so that application of Penicillin V can often be expected to have a good therapeutic effect.

Adolescent↗

PubMed1975

Alpha chain disease: immunoglobulin abnormalities, pathogenesis and current concepts.

The laboratory findings upon which the diagnosis of alpha chain disease relies and the main results of immunochemical, structural and biosynthetic studies of the pathological immunoglobulin are reviewed briefly. The pathogenesis of the disease is discussed in view of its possibly non-malignant nature at the early stage and of its peculiar geographic distribution, suggesting the triggering role of an intestinal micro-organism.

Diagnosis, Differential↗

PubMed1979

[Immunotherapy of malignant growths (author's transl)].

Our knowledge of antigens which are associated with different types of malignant tumours is steadily increasing. These antigens exist in considerable numbers, but, so far with few exceptions, only their presence can be demonstrated by certain methods; to isolate and identify them has not yet been possible. These antigens are, therefore, suitable not so much for the primary diagnosis, but rather, like the carcinoembryonic antigen, the tissue-polypeptide antigen or the alpha-feto-protein, for assessing the success of treatment. Active immunization has recently received a fresh impulse by the use of the enzyme neuraminidase, derived from Vibrio cholerae, in the treatment of tumour cells. There is no passive specific immunotherapy in human cancer. As to specific active immunotherapy BCG, Corynebacterium parvum and preparations of these and other micro-organisms together with polynucleotides, levamisol, statolon, tilorone have been employed. Although the results are not uniform they are promising. Attempts at cellular transfer of immunity are not very encouraging. It should be emphasized that the findings apply to human cancer. Experimental studies have produced very interesting results.

Animals↗