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Biomedical subjects

G Terplan

Publications and source records attributed to G Terplan.

At least 19 recordsLinked to original sources
PubMed1994

Bacillus cereus in infant foods and dried milk products.

Dried milk products and infant food are known to be frequently contaminated with Bacillus cereus. Sources of the organism and its behaviour in the product and in the equipment during processing are discussed. With regard to the incidence of B. cereus in infant food, 261 samples distributed in 17 countries were collected and examined for its B. cereus content. Fifty-four percent of the samples were contaminated with B. cereus reaching levels from 0.3 to 600/g. Counts higher than 10/g were found in only 27 samples (10%). Most of the positive samples (44%) contained 0.3 to 10 B. cereus/g. Four samples (1.5%) were contaminated with more than 100 organisms/g reaching a maximum level of 600 B. cereus/g. When classified into different types of products about 50% of the infant formulae based on milk, the follow-on formulae and the weaning foods were contaminated with B. cereus as well as 69% of those based on soy protein and 92% of the special dietetic foods. Compared to our earlier studies from 1982/83, the percentage of contaminated samples from Germany increased from 31% to 70% in the case of infant formulae, from 28% to 55% in the case of follow-on formulae, and from 40% to 100% in the case of special dietetic food. The percentage of weaning food contaminated with B. cereus remained nearly unchanged. It should be stressed, however, that the numbers of B. cereus were almost the same in both studies with the highest count in 1982/83 being 460 and in 1992 600/g. Samples naturally contaminated with counts of about 100 B. cereus/g were reconstituted and incubated at a room temperature of 27 degrees C. Levels of 10(5) B. cereus/g were reached after 7-9 h. Toxigenicity of B. cereus in dried milk products and infant food as well as food poisoning outbreaks attributed to B. cereus are discussed.

Animals↗
PubMed1994

Enzyme immunoassay for the detection of isoxazolyl penicillin antibiotics in milk.

Polyclonal antibodies were raised against isoxazolyl penicillins in rabbits after immunization with a cloxacillin-human serum albumin conjugate. The antisera were tested in direct and indirect competitive enzyme immunoassays (EIAs), using glucose oxidase or horseradish peroxidase conjugates of oxacillin, cloxacillin, or dicloxacillin, respectively, as the labelled antigen. The relative cross-reactivities of each test system with oxacillin, cloxacillin, and dicloxacillin, determined from the amount of antibiotic required for 50% inhibition of labelled antigen binding, were dependent on the antibiotic used as the labelled antigen. Other beta-lactam antibiotics did not cross-react in these test systems. In a direct EIA using a cloxacillin-horseradish peroxidase conjugate, cloxacillin and dicloxacillin in milk were detected at levels of 10 and 30 ng ml-1; the average recoveries at these levels were 102 and 84%, respectively.

Animals↗
PubMed1992

Studies on the application of enzyme immunoassays for the Fusarium mycotoxins deoxynivalenol, 3-acetyldeoxynivalenol, and zearalenone.

Polyclonal antisera against zearalenone (ZEA) were produced in rabbits after immunization with ZEA-oxime coupled to human serum albumin. Using these antibodies and a ZEA-oxime-horseradish peroxidase conjugate in a competitive direct enzyme immunoassay (EIA), the detection limit for ZEA was 70 pg/ml. The relative cross-reactivities of the assay with ZEA, alpha-zearalenol, beta-zearalenol, zearalanone, alpha-zearalanol, and beta-zearalanol, respectively, were 100%, 37.3%, 7.2%, 59.2%, 5.3%, and 3.9%, respectively. This EIA and two EIAs for deoxynivalenol (DON) and 3-acetyldeoxynivalenol(3-AcDON) (Usleber et al., 1991) were used to analyze wheat samples. The limits of determination for DON, 3-AcDON, and ZEA in wheat were 200 ppb, 50 ppb, and 20 ppb, respectively. The analysis of reference materials (wheat flour) containing DON by EIA showed good agreement with the nominal values. The EIA for ZEA was in addition used to analyze biological fluids, obtained during a feeding trial. Two lactating cows were administered 25 mg and 100 mg ZEA per day, respectively, over a period of 6 days. Serum, milk, urine, and feces were assayed in the ZEA-EIA with and without sample treatment with beta-glucuronidase prior to the analysis. Maximum toxin levels (ZEA-equivalents) found in milk were 0.4 and 1.2 ppb (glucuronides). The toxin concentration in milk decreased rapidly after the last toxin administration. In the urine, maximum levels of toxin-glucuronide conjugates were 23 ppb and 24 ppb, respectively. The serum toxin levels corresponded to those found in milk. In the feces, mean values were 150 ppb and 500 ppb, respectively, no conjugated toxins were found in feces.

Animals↗
PubMed1991

[Detection of antibodies against the larva of Anisakis simplex in the pollock Pollachius virens using ELISA].

From the fact that older saithes (more than 5 years old) are showing significantly lower prevalence of attack by Anisakis larvae in lateral muscle than younger saithes (3-4 years old), the question arises if this phenomenon is based on a specific immune response. Therefore we have investigated serum samples from saithes of different ages by using an indirect ELISA to estimate the antibody-titer against excretory-secretory Anisakis antigen. Results showing a moderate correlation (r = 0.66) between the height of titer and the age of underfeeding saithes (post spawning) and a close correlation (r = 0.93) of saithes in an optimal condition (pre spawning). It may be concluded that the migration-distance and the lifetime of Anisakis larvae in lateral-muscle is influenced by a specific immune response which increases with the age of the saithes.

Age Factors↗
PubMed1989

A survey on the occurrence of Fusarium mycotoxins in Bavarian cereals from the 1987 harvest.

Bavarian cereals and wheat flour from the 1987 harvest were analysed for nivalenol (NIV) and deoxynivalenol (DON) using high performance liquid chromatography (HPLC) and for T-2 toxin and zearalenone (ZEA) by enzyme-linked-immunosorbent assay (ELISA). The study included 190 field samples of wheat, barley, rye and oat with visibly damaged ears, 45 samples of wheat intended for feed production and two series of wheat flour (type 550) and whole wheat flour collected in October 1987 and June 1988. The field samples examined showed a high DON contamination of wheat (87%) with an average of 3.96 mg/kg and a maximum of 43.8 mg/kg. Mean levels between 0.33 mg/kg and 0.27 mg/kg DON could be detected in barley, rye and oat. Of the wheat samples, 58% contained ZEA with a maximum of 1.560 mg/kg. The highest levels of ZEA were detected in samples which also showed high concentrations of DON. The NIV and T-2 toxin levels were comparatively low. Thirty percent of the samples showed NIV concentrations between 0.04 mg/kg and 0.29 mg/kg and 38% contained between 0.005 and 0.60 mg/kg of T-2. In the wheat samples for feed production, only DON was detected with an average of 0.190 mg/kg and a maximum of 0.75 mg/kg. The highest DON levels (0.58 mg/kg) from October 1987 were found in the wheat flour samples which were lower than the highest DON concentration (3.24 mg/kg) detected in the samples collected during June 1988. This fact was probably due to a substantial amount of non-contaminated wheat from 1986. The toxin concentrations in the whole wheat flour were not higher than in the type 550 flour.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMed1989

Investigations on the pathogenicity of Listeria spp. by experimental infection of the chick embryo.

To investigate the pathogenicity of Listeria spp., chick embryos were infected by two methods. Very encouraging results were obtained with the inoculation of the chorioallantoic membrane (CAM) of 10 day old chick embryos: embryos inoculated with pathogenic strains (L. monocytogenes or L. ivanovii) died within 72 h, whereas those infected with apathogenic strains survived. This test could be a suitable method to replace the mouse pathogenicity test.

Allantois↗
PubMed1988

Development of a sensitive enzyme-linked immunosorbent assay for the detection of diacetoxyscirpenol.

An enzyme-linked immunosorbent assay (ELISA) for the detection of diacetoxyscirpenol (DAS) was developed. Antibodies against DAS were obtained after immunization of rabbits with DAS-hemiglutarate-human serum albumin (DAS-HG-HSA). After an immunization period of 6 weeks a sufficient level of specific antibodies was reached. A DAS-hemisuccinate-horseradish peroxidase-conjugate (DAS-HS-HRP) was prepared by an ester method and used as enzyme-labelled toxin in the competitive assay. The detection limit for DAS was about 10 pg/ml. The relative cross reactivity of the assay was 597.5, 5.2, 100.0, 2.5, and 1.5% for 3 alpha-acetyl-DAS, DAS, T-2 toxin, neosolaniol, and 15-acetoxyscirpenol, respectively.

Animals↗
PubMed1988

Enzyme immunoassay for the macrocyclic trichothecene roridin A: production, properties, and use of rabbit antibodies.

Antisera against roridin A were prepared by using a roridin A-hemisuccinate derivative coupled to human serum albumin as the immunogen. Antibodies could be detected in the sera of the immunized rabbits as early as 4 weeks after the initial exposure. After one booster injection at week 14, high antibody titers were measured over a period of 21 weeks. The specificity and sensitivity of the antibodies were tested by using roridin A-hemisuccinate coupled to horseradish peroxidase as an enzyme-linked toxin in a competitive assay with a double-antibody solid phase. The assay was most specific for the tested macrocyclic trichothecenes, and the relative cross-reactivities with roridin A, roridin J, verrucarin A, satratoxin H, and satratoxin G were 1, 0.41, 0.15, 0.15, and 0.07, respectively. When 16 nonmacrocyclic trichothecenes were tested, only diacetylverrucarol (0.0015) and verrucarol (0.0005) showed minor cross-reactivity. The sensitivity of the enzyme immunoassay for the detection of roridin A was in the range of 5 to 50 ng/ml (0.16 to 1.6 ng per assay).

Animals↗
PubMed1988

Production and characterization of monoclonal antibodies to the macrocyclic trichothecene roridin A.

Two murine monoclonal antibodies to the macrocyclic trichothecene roridin A are described. Screening for antibody production was performed on absorbed anti-mouse immunoglobulin serum as double-antibody solid phase, and further characterization was done on affinity-purified anti-mouse IgG serum. The antibodies, designated 5G11 and 4H10, had affinity constants for roridin A of 9.25 X 10(7) and 1.7 X 10(7) liters/mol, respectively. In monoclonal antibody-based direct enzyme immunoassays, these IgG1 antibodies had detection limits for roridin A of 0.4 ng/ml (0.02 ng per assay) and 1.8 ng/ml (0.09 ng per assay), respectively. Both antibodies were most specific for the tested macrocyclic trichothecenes. The relative cross-reactivities of antibody 5G11 with roridin A, roridin J, verrucarin A, satratoxin G, and satratoxin H were 100.0, 43.8, 16.7, 3.7, and 18.9%, respectively; for antibody 4H10 they were 100.0, 6.3, 64.0, 4.4, and 4.9%, respectively.

Animals↗
PubMed1984

[Incidence of Bacillus cereus and various pathogenic microorganisms in food for infants and small children].

206 samples of commercially available infant food and their ingredients were examined for the content of B. cereus and coagulase-positive staphylococci as well as for the presence of salmonellae. B. cereus could be isolated from 64 samples with numbers between 3 and 460/g (only 2 samples greater than 100/g). Two samples contained coagulase-positive staphylococci (4/g each), and no sample salmonellae. Growth of B. cereus in reconstituted samples with counts of less than or equal to 100/g incubated at 20 and 25 degrees C, reached counts of 10(3)-10(4)/g after 6-9 h and 3-6 h, respectively. With regard to productivity and selectivity no differences between the media used (mannitol-egg yolk-phenolred-polymyxin-agar according to Mossel, Koopman and Jongerius, and polymyxin-pyruvate-egg yolk-mannitol-bromthymol blue-agar according to Holbrook and Anderson) could be observed.

Bacillus cereus↗
PubMed1983

Chromatofocusing: a new method for purification of staphylococcal enterotoxins B and C1.

A new chromatographic procedure was developed which obtained highly purified preparations of staphylococcal enterotoxins B and C1 in yields of 60% from cultures of Staphylococcus aureus and which is faster than any of the separation methods used previously. The procedure involves chromatography on carboxymethylcellulose, removal of alpha-toxin by adsorption to rabbit erythrocyte membranes, and finally, chromatofocusing as the fundamental new step. Enterotoxins were obtained in highly purified form and behaved in a homogeneous manner as determined by ultracentrifugation and electrophoresis on polyacrylamide gel in the presence of sodium dodecyl sulfate, with molecular weights of 34,000 for staphylococcal enterotoxin B and 30,000 for staphylococcal enterotoxin C1. Using chromatofocusing as the final purification step, we isolated three B and six C1 distinct but immunologically identical enterotoxin fractions, which were found to be devoid of any impurities and to possess a marked degree of toxicity in monkeys.

Chromatography↗
PubMed1983

[Suitability of current selective media for the detection of Staphylococcus aureus in food].

Three solid media (Baird-Parker-Agar (BP), BP with pig plasma instead of egg-yolk (BPP) and modified BP according to Devriese (BPA) as well as three liquid media (Brain-Heart-Infusion with 7.5% NaCl (BHIS), Liquid Baird-Parker-Medium (LBP) and Giolitti-Cantoni-Medium) were tested with regard to their suitability for the detection of Staph. aureus in foods. The following criteria were assessed: productivity for vital and thermally stressed Staph. aureus; selectivity against undesired microorganisms; practicality in routine examination. The microorganisms used in these studies were: Staph. aureus (vital and thermally stressed), "non-aureus" staphylococci, Streptococcus spp., Pseudomonas spp., Proteus spp., Bacillus spp. Using vital strains of Staph. aureus no significant differences in the productivity of the three solid media could be observed. On the other hand BPA showed a remarkable lower productivity than BP and BPP when thermally stressed cultures of Staph. aureus were examined. LBP was the most productive liquid enrichment medium. The selectivity of BPA was distinctly superior to BP and BPP, whereas no differences could be observed between the latter ones. The selectivity of LBP and GC against coagulase negative staphylococci and gramnegative microorganisms tested was relatively poor. Each culture under examination grew in BHIS. The combination of LBP and BPA yielded better results for enumeration of thermally stressed Staph. aureus from dried milk products than the other possible combinations of media. In view of their practicality dehydrated culture media are commonly preferred in routine examination. The additional time required for the preparation of LBP or BPA (which are not commercially available as dehydrated media) is negligible and is compensated by better productivity and selectivity of these media. At present BPP is not recommendable due to the problems in providing pig plasma. On the other hand this medium has the great advantage that further testing of suspicious colonies is not necessary as it is in the case of BP and BPA.

Animals↗
PubMed1980

[The role of water in the production and processing of milk (author's transl)].

Water is used in various ways in milk production and dairy industry, thereby becoming part of the food intentionally, inevitably or accidentally. The contamination of the food by water-borne microorganisms occurs directly, much more often, however, indirectly after multiplication of these microorganisms on the cleaned surfaces of the equipment used. Decisive for the influence of these microorganisms on the quality of milk and dairy products are the number and characteristics of the microorganisms, the extrinsic factors and the properties of the food. The various possibilities of an influence resulting from the microbiological quality of the water are exemplarily shown for raw milk, pasteurized milk, butter and cheese. The requirements concerning the water used in milk producing and processing plants are settled in the drinking-water-regulation. The bacteriological requirements of this regulation, however, don't absolutely guarantee a water of good technologic-hygienic quality. Doubts about the use of cooling water, which must not show the quality of drinking water, arise only with regard to pathogenic microorganisms.

Animals↗
PubMed1979

[Bovine mastitis: a problem of veterinary medicine, economics and food hygiene (author's transl)].

Veterinary medicine, dairying, and consumers are likewise interested in mastitis control. The veterinary point of view includes health and function of the udder as well as the production of milk of hygienic quality. Investigations in 6 dairy farms showed that a mastitis control program improved the udder health and resulted in economic benefits. Up to 67% of the subclinical infected udder quarters could be eliminated by prophylactical control measures, especially teat dipping and dry cow therapy. The frequency of clinical udder infections was reduced by about 50%. Furthermore in the first year 5.1% and 7.1% increase of milk and fat yield respectively could be noticed for cows being subject to the program for the whole time. These values could not be reached in the second year. In one herd the milk production increased by about 10% after a control period of two years. The owner of this herd (ca. 35 cows), who was very engaged in the program, obtained an economical benefit of ca. 3500 DM in the first and 7300 DM in the second year of the program. This realised a profit of1.85 DM in the first year and 3.85 DM in the second year per each DM cost in the control program. Mastitis as well as control measures do not implicate a special risk for the human health, because food and drug regulations enable the protection of the consumer in an optimal manner.

Animals↗