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W Kneifel

Publications and source records attributed to W Kneifel.

At least 19 recordsLinked to original sources
PubMed2002

Clustering of Saccharomyces boulardii strains within the species S. cerevisiae using molecular typing techniques.

AIMS: This study was undertaken to characterize and differentiate therapeutically relevant Saccharomyces yeasts. Among the isolates were so-called Saccharomyces boulardii strains, which are considered as probiotic agents, but whose taxonomic assignment is controversial. Moreover, the discriminative power of the applied molecular typing techniques should be evaluated. METHODS AND RESULTS: Genotyping was performed using species-specific polymerase chain reaction (PCR), randomly amplified polymorphic DNA-PCR, restriction fragment length polymorphism analysis of rDNA spacer regions and pulsed-field gel electrophoresis. Species-specific PCR assigned all of the product isolates to the species S. cerevisiae. By combining the other techniques, all isolates could be discriminated. Moreover, it could be demonstrated that probiotic S. boulardii strains form a separate cluster located within the species. CONCLUSIONS: With the exception of species-specific PCR, all of the applied methodologies were suitable for subspecies typing and indicated a close relationship between the probiotic strains. SIGNIFICANCE AND IMPACT OF THE STUDY: The methods applied in this study are considered powerful tools for quality control of therapeutically relevant yeasts. It is of crucial importance, especially regarding S. boulardii yeasts, to verify the identity of the correct strain, since the beneficial properties are considered to be strain-specific.

DNA, Fungal↗
PubMed2002

A collaborative study of a method for enumeration of probiotic enterococci in animal feed.

AIMS: Validation of an enumeration method to be used as an official control method in the framework of Council Directive 70/524/EEC for probiotic enterococci used as feed additives. METHODS AND RESULTS: Twenty laboratories in 12 European countries carried out a collaborative study. A plate count method using bile esculin azide (BEA) agar was used. Precision data in terms of repeatability (r) and reproducibility (R) of the method using different feeding stuffs and three inoculation levels were determined. Enterococci were present in the samples as a single component or in mixtures with other probiotic feed additives. The enumeration of enterococci on BEA agar showed a relative standard deviation (RSD)r of 1.5-3.6% and an RSD(R) between 2.9 and 7.4%. BEA agar was selective for enterococci in the presence of other probiotic micro-organisms such as pediococci, lactobacilli and yeast. CONCLUSIONS: For routine analysis of viable enterococci concentrations in feeding stuffs, the use of BEA is recommended. This methodology is not applicable for mineral feeds. SIGNIFICANCE AND IMPACT OF THE STUDY: An official control method for enumeration of authorized probiotic enterococci in feeding stuffs was validated. The results are intended for consideration for adoption as CEN and ISO standards.

Animal Feed↗
PubMed2001

Utilization of prebiotic carbohydrates by yeasts of therapeutic relevance.

AIMS: To investigate 17 strains of therapeutically relevant strains of Saccharomyces cerevisiae (including 10 strains of so-called S. boulardii) isolated from various pharmaceutical products, feed supplements and brewer's yeast for their capability of utilizing selected carbohydrates of prebiotic importance. METHODS AND RESULTS: Automated turbidimetric measurements and conventional test combinations were used to examine the basic sugar assimilation profiles of the test strains. It was shown that none of the so-called S. boulardii strains utilized galactose and palatinose. Among the prebiotic substrates, the yeasts indicated a pronounced preference for metabolizing the fructo-oligosaccharides. CONCLUSION: Yeast strains of therapeutic relevance can be successfully combined with certain prebiotics in symbiotic formulations. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study may serve as a basis for the development of new pharmaceutical preparations for medical therapy and a better understanding of intestinal micro-ecology.

Carbohydrate Metabolism↗
PubMed2001

Microbiological status of commercially available medicinal herbal drugs--a screening study.

One hundred and thirty-eight medicinal herbal drugs obtained from different suppliers were examined for microbial contaminants and for the detectability of pathogenic microorganisms. For this purpose, several microbiological standard parameters (total aerobic mesophilic count, enterobacteria, coliforms, aerobic sporeformers, yeasts and moulds, enterococci, lactobacilli, pseudomonades and aeromades) and selective methods for the detection of indicator microorganisms and pathogens (E. coli, enterohaemorrhagic E. coli [EHEC], Salmonella, Campylobacter jejuni, Pseudomonas aeruginosa, Bacillus cereus, Clostridium perfringens, Listeria, coagulase-positive staphylococci, Candida albicans, potentially aflatoxigenic moulds) were applied. The microbial load of the samples varied considerably. While none of the samples contained EHEC, Salmonellae, Pseudomonas aeruginosa, Listeriae, Staphylococcus aureus or Candida albicans, four samples were E. coli positive, two samples were presumptively Campylobacter jejuni positive and nine herbal drugs contained a potentially aflatoxigenic mould flora. Further details regarding different viable count classes as well as preparation techniques are discussed.

Bacteria↗
PubMed2001

Endocarditis by Lactobacillus rhamnosus due to yogurt ingestion?

A young man who ate large quantities of probiotic yogurt developed endocarditis and septic arthritis caused by Lactobacillus rhamnosus. The pathogenic isolate could not be distinguished from the yogurt microflora using methods routinely used in the clinical microbiology laboratory. Only by using more appropriate methodology, including PCR, the pathogen could be distinguished from the yogurt isolate.

Adult↗
PubMed2001

Continuous venovenous hemofiltration improves arterial oxygenation in endotoxin-induced lung injury in pigs.

BACKGROUND: Hypoxemia is common in septic acute lung failure. Therapy is mainly supportive, and most trials using specific inhibitors of key inflammatory mediators (ie., tumor necrosis factor alpha, interleukin 1) have failed to prove beneficial. The authors investigated if a nonspecific blood purification technique, using zero-balanced high-volume continuous venovenous hemofiltration (CWH), might improve arterial oxygenation in a fluid-resuscitated porcine model of endotoxin-induced acute lung injury. METHODS: Piglets of both sexes weighing 25-30 kg were anesthetized and mechanically ventilated. After baseline measurements, animals received an intravenous infusion of 0.5 mg/kg endotoxin (Escherichia coli lipopolysaccharide). One hour after endotoxin, animals were randomly assigned to either treatment with CWH (endotoxin + hemofiltration, n = 6) or spontaneous course (endotoxin, n = 6). At 4 h after randomization, animals were killed. Hemofiltration was performed from femoral vein to femoral vein using a standard circuit with an EF60 polysulphone hemofilter. RESULTS: Endotoxin challenge induced arterial hypoxemia, an increase in peak inspiratory pressure, pulmonary hypertension, and systemic hypotension. Treatment with CWH did not improve systemic or pulmonary hemodynamics. However, arterial oxygenation was increased in endotoxin-challenged animals at 5 h after completion of endotoxin infusion, as compared with animals not receiving CVVH (arterialoxygen tension, 268+/-33 vs. 176+/-67 mm/Hg, respectively, P < 0.01). In addition, treatment with CWH attenuated the endotoxin-induced increase in peak inspiratory pressure and increased lung compliance. CONCLUSION: These results suggest that nonspecific blood purification with high-volume CWH improves arterial oxygenation and lung function in endotoxin-induced acute lung injury in pigs, independent of improved hemodynamics, fluid removal, or body temperature.

Animals↗
PubMed2000

Influence of a synbiotic mixture consisting of Lactobacillus acidophilus 74-2 and a fructooligosaccharide preparation on the microbial ecology sustained in a simulation of the human intestinal microbial ecosystem (SHIME reactor).

Lactobacillus acidophilus 74-2, which is used in probiotic products, was administered, with fructo-oligosaccharide in a milk-based product, to the second vessel (duodenum/jejunum) of the SHIME reactor, an in vitro simulation of the human intestinal microbial ecology. The main focus of this study was to monitor the changes of the population density of selected bacterial species in the intestine and the changes of metabolic activities during the supplementation of L. acidophilus and fructooligosaccharide in the SHIME reactor. Interestingly, the addition of L. acidophilus 74-2 with fructooligosaccharide gave rise to an increase of bifidobacteria. Moreover, major positive changes occurred in the production of volatile fatty acids: a strong upward trend was observed especially in the case of butyric acid and propionic acid. Furthermore a noticeable increase of beta-galactosidase activity was monitored, while the activity of beta-glucuronidase, generally considered undesirable, declined.

Animals↗
PubMed1997

The HELLP syndrome.

Explore the source record for details and available documents.

Analgesia, Obstetrical↗
PubMed1993

Microflora and acidification properties of yogurt and yogurt-related products fermented with commercially available starter cultures.

Yogurts and yogurt-related milk products were produced using 44 commercially available starter cultures from 8 suppliers. The yogurt starters consisted of the classical yogurt microflora and the yogurt-related cultures containing Lactobacillus acidophilus and/or Bifidobacterium spp. instead of or in addition to the yogurt bacteria. The counts of lactobacilli in the fresh yogurts varied between 5.5 x 10(7) and 6.5 x 10(8) CFU/ml, and the counts of streptococci varied from 3.5 x 10(7) to 1.2 x 10(9) CFU/ml. About 80% of the yogurts had higher counts of cocci than rods. During storage of the products for 2 weeks at 6 degrees C the stability of the microflora differed markedly among the cultures. In the fresh yogurt-related products the L. acidophilus counts ranged from 4.0 x 10(5) to 2.6 x 10(8) CFU/ml; bifidobacteria were found at levels between 4.0 x 10(6) and 2.6 x 10(8) CFU/ml. In most products reduced viable counts of these bacteria were observed after 2 weeks. Titratable acidity increased on average by 22.3% in the yogurts, and by 14.9% in the yogurt-related products during storage. In most products a higher amount of L(+)- than D(-)-lactic acid was found.

Bifidobacterium↗
PubMed1992

Adaptation of two commercially available DNA probes for the detection of E. coli and Staphylococcus aureus to selected fields of dairy hygiene--an exemplary study.

The application of two commercially available colorimetric DNA hybridization tests (GENE-TRAK E. coli and Staphylococcus aureus) to selected aspects of dairy hygiene was investigated. Bacterial isolates of different origin, naturally contaminated cheese varieties, nonfat dry milk, milk concentrates, artificially contaminated milk and raw milks from udder quarters were examined. Based on the observation that the sensitivity of the E. coli DNA probe was comparable to that of the beta-D-glucuronidase-based fluorescence reaction (with 4-methyl-umbelliferyl-beta-D-glucuronide) of E. coli strains in Fluorocult lauryl sulfate broth, a Most Probable Number technique for enumerating E. coli in cheese using the DNA probe was developed. Another specific DNA probe was applied for the detection of S. aureus as a mastitis agent. By using a modified sample preparation, specific diagnosis of this microorganism in milk from udder quarters was enabled within 6 hours. This procedure is recommended to be used in screening tests. Based on the examples presented the potential of these tests in several fields of hygiene was illustrated.

Animals↗
PubMed1991

Fluorogenic and chromogenic substrates used in bacterial diagnostics.

Methods based on the application of chromogenic and fluorogenic substrates enable specific and rapid detection of a variety of bacterial enzymatic activities. By using these techniques, enzymatic reactions can be examined simultaneously or individually, either directly on the isolation plate or in cell suspensions. For this purpose, various testing principles and test kits for clinical and food microbiology have been introduced successfully during the last few years. In this paper we present a survey of different enzymes of microbial origin that are utilized for microbiological identification and differentiation and the corresponding methods. Particular emphasis is given to the examination of Escherichia coli and the description of the different techniques as used in routine analysis.

Bacteria↗
PubMed1991

Fluorogenic and chromogenic substrates--a promising tool in microbiology.

During the last few years the use of fluorogenic and chromogenic substrates for rapid and sensitive detection of bacteria has proved to be a powerful alternative to traditional methods. These sophisticated substrates might find widespread application in, for instance, the assay of clinically important enzymes, flow cytometry, and direct epifluorescent filter technique. Specific enzyme detection offers another approach to differential identification and characterization of viable bacteria from a sample. The use of some chromogenic and fluorogenic substrates specific for bacterial enzymes and their applications to microbial identification is reported. Particular emphasis is given to the examination of Escherichia coli and the description of the different techniques as used in routine analysis.

Bacteria↗
PubMed1990

Rapid methods for differentiating gram-positive from gram-negative aerobic and facultative anaerobic bacteria.

Different tests based on lysis by KOH and on reaction with fluorogenic and chromogenic substrates, L-alanine-4-nitroanilide (LANA); L-alanine-4-methoxy- beta-naphthylamide (MNA); 4-alanine-2-amidoacridone (AAA); L-alanine-7-amido- 4-methylcoumarin (AAMC); 8-anilino-1-naphthalene-sulphonic acid (ANS) were compared for their suitability to distinguish Gram-positive from Gram-negative bacteria. A concentration of 100 micrograms/ml was chosen for incorporating LANA, AAA, AAMC and ANS into the growth medium, based on sensitivity tests. MNA did not show any detectable reaction over a concentration range from 50 to 200 micrograms/ml, and led to inhibition of all bacteria at 200 micrograms/ml. In the examination of a total of 146 bacterial strains, including Yersinia enterocolitica, Bacillus cereus, and B. subtilis the KOH test was not comparable with the Gram staining. A good correlation with Gram staining was found between LANA, AAA and AAMC added to plate count agar on one hand, and LANA and AAMC impregnated paper strips on the other hand, thereby utilizing the aminopeptidase activity. Agar containing ANS showed detectable fluorescence with all Gram-negative strains, but with Staphylococcus aureus and Staph. epidermidis a weak reaction was also observed. AAMC was selected for a rapid paper strip test. With this substrate a pronounced blue fluorescence was obtained with Gram-negative colonies.

Animals↗
PubMed1989

[A combined chromogenic-fluorogenic medium for the simultaneous detection of coliform groups and E. coli in water].

A comparison was made with different chromogenic and fluorogenic substrates, 4-methylumbelliferyl-beta-D-glucuronide (MUG), 4-nitrophenyl-beta-D-glucuronide (PNPG), 4-methylumbelliferyl-beta-D-galactopyranoside (MUGA), 2-nitrophenyl-beta-D-galactopyranoside (ONPG), 5-bromo-4-chloro-3-indolyl-beta-D-galactopyranoside (X-GAL), for the rapid and simultaneous enumeration of total coliforms and E. coli in water samples, based on 2 commercially available culture-media. The combination of the chromogenic compound X-GAL (for detecting coliforms) and of the fluorogenic compound MUG (for detecting E. coli) incorporated either into ECD agar or into lauryl sulfate broth proved to be most useful. The optimum concentration of the X-GAL/MUG supplement was (50 micrograms/ml/70 micrograms/ml) for the solid medium (EMX agar) and (60 micrograms/ml/70 micrograms/ml) for the fluid medium (LMX broth). As a result of the examination of 244 Enterobacteriaceae strains isolated from water samples and clinical material, it was shown that the use of EMX agar (LMX broth) had several advantages over conventional methods. A routine method for the analysis of water samples was proposed involving the EMX agar and the LMX broth.

Chromogenic Compounds↗