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Currently, there is little evidence-based guidance on bacteriological aspects of thickeners or beverages for dysphagia patients in Germany that can be recommended to prevent aspiration pneumonia. Therefore, the aim of this study was to evaluate the lowest cell amount of E. coli on M9 agar media with beverages and thickeners.In the laboratory experiment 1 · 10The lowest E. coli cell amount was measured on water compared to beer, orange juice and all thickeners. A higher E. coli cell count was measured on maltodextrin-based thickeners than on potato starch-based and corn starch-based thickeners.In the present laboratory experiment, no individual risk factors for the development of aspiration pneumonia in humans were considered; however, initial bacteriological evidence for dysphagia patients could be collected. Due to the high growth of E. coli on maltodextrin, yeast, fructose and glucose, these ingredients should be used with caution by dysphagia patients. Further research on thickeners and beverages is needed to make a comprehensive recommendation for action in this aspect.HINTERGRUND: Gegenwärtig existieren in Deutschland für Dysphagiepatienten kaum Hinweise zu bakteriologischen Aspekten von Andickungsmitteln oder Getränken, die präventiv vor einer Aspirationspneumonie empfohlen werden können. Ziel dieser Studie war daher die Evaluierung der geringsten Zellzahl von E. coli auf M9-Agar-Nährmedien mit Getränken und Andickungsmitteln.In dem Laborexperiment wurden 1 · 10Auf Wasser wurde im Vergleich zu Bier, Orangensaft sowie zu allen Andickungsmitteln die geringste E. coli-Zellzahl gemessen. Es wurde eine höhere Zellzahl von E. coli auf Andickungsmitteln mit Maltodextrinbasis als auf Andickungsmitteln mit Kartoffel- und Maisstärkebasis gemessen.In dem vorliegenden Laborexperiment wurden keine individuellen Risikofaktoren für die Entwicklung einer Aspirationspneumonie beim Menschen berücksichtigt. Jedoch konnten erste bakteriologische Hinweise für Dysphagiepatienten gesammelt werden. Aufgrund des hohen Wachstums von E. coli auf Maltodextrin, Hefe, Fructose und Glucose sollten diese Inhaltsstoffe mit Vorsicht von Dysphagiepatienten verwendet werden. Es ist weitere Forschung zu Andickungsmitteln und Getränken notwendig, um eine umfassende Handlungsempfehlung diesbezüglich aussprechen zu können.

Introduction Mucosa-associated E.coli are commonly found in patients with Crohn’s disease (CD), colorectal cancer (CRC) and to a lesser extent in ulcerative colitis (UC)1,2. They are able to replicate within macrophage phagolysosomes and are found inside CD tissue macrophages3,4. Our aim here was to assess these mucosal E.coli isolates for ability to tolerate stress conditions characteristic of that found within the phagolysosome. Methods E.coli isolates from patients with CD (n = 16), UC (6), CRC (7), and those obtained from other patients (n = 7; IBS (2), sporadic polyps (3), piles (1), healthy individuals (3)) and laboratory strains (6) were grown in LB medium (OD600nm 0.1). Ten-fold dilutions were plated under stress conditions; 100 mM MES pH5 with or without 1 mM NaNO2 (low pH and nitrosative stress), 1 mM H2O2 pH7 (peroxidative stress), 1 mM methyl viologen pH7 (superoxidative stress) and compared to growth on LB agar pH7. Data was correlated with ability of isolates to replicate within J774 macrophages.4 Host oxidative stress response of macrophages infected with either CD isolate HM605 or E.coli K12EPI300 (susceptible to macrophage killing) were studied. cDNA synthesised from isolated RNA, was subjected to Qiagen RT2 PCR Oxidative stress arrays (n = 3 replicates/arrays performed for condition). Results CD isolates showed greater tolerance to superoxidative stress than isolates from UC, CRC and other patients/laboratory E.coli strains (p 2-fold) in both E.coli HM605- and K12EPI300-infected macrophages compared to uninfected controls (p Conclusion CD mucosa-associated E.coli are tolerant of superoxidative stress to support their survival and replication within host macrophages. Adaptation to the phagolysosome niche appears not to be through ability to alter host oxidative stress response to infection. References 1 Thomazini, et al. Int J Med Microbiol 2011;301:475–79. 2 Martin, et al. Gastroenterology 2004;127: 80–93. 3 Bringer, et al. Cell. Microbiol 2006;8:471–84. 4 Subramanian, et al. AAC 2008;52:427–34. Disclosure of Interest A. Tawfik: None Declared, J. Rhodes Consultant for: is/has been a member of advisory boards for Atlantic, Procter & Gamble and Falk, Conflict with: has received honoraria from Abbott, Falk, Ferring, Glaxo Smith Kline, Procter & Gamble and Schering Plough, B. Campbell Conflict with: has received honoraria from Amgen, Falk and Enterome

In static magnetic resonance elastography, the elasticity of an object is determined by measuring the internal displacement between two compression states. To reduce signal loss during the long time delay between application of external deformation and the static compression state, a STEAM sequence with a long mixing time is used This results in long scan times. The aim of this work was the development of a STEAM sequence with a multi-echo-readout, which allows the reduction of scan time and number of necessary external deformations. This new sequence was compared to the standard STEAM sequence on an agarose gel phantom with a hard inclusion. In addition, the elasticity of thermal tissue lesions was investigated, which were induced using high-intensity focused ultrasound (HIFU). During a given measurement time, more acquisitions per image can be taken using the multi-echo-readout. As a result the signal-to-noise ratio is increased and errors in the data become clearly smaller. Drawbacks of. the new sequence are its higher signal loss due to T2-decay and its greater sensitivity against ghosting artefacts caused by k-space segmentation. During the investigation of the thermally-induced lesions, a clear contrast in elasticity between normal tissue and the treated region was observed. Taking advantage of the greater accuracy of the new STEAM sequence, it was shown, that this contrast is significantly larger than the one in conventional MR parameters.

The aim of our study was to develop a practical test for assessing the effectiveness of the microbial barrier of packaging materials for sterile products. The suitability of the test was verified in the exemplary case of double-wrapped sterilized trays. During testing, the bacterial count of the ambient air was 35 and 440 colony-forming units/cubic metre. The test is based on the co-sterilization in the sterile packing of petri dishes containing CASO agar, which at the end of the test were investigated for re-contamination. The petri dishes covered the sterilizing sieves as completely as possible. After sterilization, the packaging was loaded 300 to 900 times at a pressure of 1 kg (5x/min). This was followed by incubation for 48 hours at 37 degrees C, and evaluation (No. of colonies). The ability of the agar to culture colonies of bacteria was preserved unchanged for a period of at least 3 weeks after sterilization. For double-wrapped trays it was shown that re-contamination increases with intensity of mechanical loading and the atmospheric bacterial count. Since the package was breached only for the analysis, confounding factors due to removal of contents for examination, were effectively excluded. This test procedure is characterised by simplicity in handling and high specificity. As a final pack test it effectively closes a gap in the quality assurance chain for sterile materials.

Differences of elasticity in tissue phantoms with inclusions of different elasticity were mapped by means of MR elastography (MRE). This new magnetic resonance imaging technique is based on the phase shift of the MR signal by switching a motion sensitizing magnetic field gradient simultaneously with the coupling of a shear wave. Wave patterns showing snapshots of the shear wave that propagates through the investigated substance were depicted in tomographic phase images. It was investigated wether a visualization of differences in elasticity of soft tissues was possible on the basis of differences in the wavelength. For this purpose, tissue phantoms with cylindrical inclusions were produced from agar gels, with agar concentrations between 1.0 and 1.5%. The diameters of the inclusions were of the order of a few centimetres. For diameters as small as 4 cm, there were still distinct differences in the wavelength between the matrix and the inclusion. The results of our study suggest that this technique has the potential for future application as an additional imaging method for tumor detection.

A method was developed for the determination of microorganism concentrations on air filters of HVAC systems, and the influence of different test parameters on the microbiological results was examined by considering various used air filters from several such systems. Microorganisms are detected by shaking air filter samples in fluid, where their concentration is then determined as surface cultures. Since varying the shaking time (30, 60, 90 min) had no influence on the quantitative microorganism determination, a shaking time of 60 minutes was chosen for detection of bacteria, yeasts and moulds. Incubation of blood agar plates either for 4 days at 20 degrees C +/- 2 degrees C or for 2 days at 36 degrees C +/- 1 degree C yielded identical concentrations of bacteria and yeasts. Since results obtained with malt extract agar and Czapek-Dox agar are comparable, one of the two culture media is sufficient for the quantitative determination of moulds on air filters. For statistical evaluation, the inoculation of three parallel agar plates per growth medium was found to be adequate, and the arithmetic mean and the median proved to be equivalent. Investigation on the detection rate showed that, on the average, the method developed demonstrated 80% of the microorganisms detectable on an air filter sample. Thus a simple method is available for quantitative determination of microorganisms on air filters.

In bacteriology, the Etest has a broad field of application in bacteriology and is recently available for the antimycotics fluconazole and itraconazole. By means of the presence of gradient concentrations of the active substance on the carrier material, it is possible to obtain reproducible MICs of the antimycotic substances. The results of susceptibility testing of 326 clinical yeast isolates with the Etest were compared to those MICs obtained by microdilution and agar dilution. A 100% concordance of the MIC markers (mode-, MIC50- and MIC90-value, standard deviation of the mean log2-MIC-dilution steps) was given when compared by a +/- 1 MIC-dilution step range with microdilution and by +/- 2 MIC-dilution steps with agar dilution; species dependent all strains were within 2 x standard deviation of the individual MIC-mean of the species. By comparison of the individual MIC-values maximum differences of +/- 6 MIC-dilution steps were obtained, where 70% of all results were within +/- 2 MIC-dilution steps, and more than 92% of all strains were within +/- 3 MIC-dilution steps. The Pearson's correlation coefficients show a good agreement of the Etest with microdilution (r = 0.92) resp., agar dilution (r = 0.88) demonstrate, however, clearly insufficient correlations (r0.65) to the reference methods, for species with difficult to read Etest inhibition zones (e.g., Candida glabrata, Candida krusei, Candida parapsilosis). The differences between the proposed test methods recommended by the NCCLS and the working group "Clinical Mycology" of the German Speaking Mycological Society (AG-KMYK) are tabled.

In 23 patients, donor sites of split-thickness skin grafts were treated with Geliperm Hydrogel, a swellable polyacrylamide agar. Healing duration, toleration, exudation and pain were all noted during the daily change of dressing. In 22 of the 23 cases, good healing was obtained after an average of 12.3 days. We feel that Geliperm is excellently suitable for covering the donor sites of split-thickness skin grafts.

Methods and evaluation of the human tumor stem cell assay (HTSCA) are described. Advantages and disadvantages of the test system are elaborated. The in vitro/in vivo correlation in the drug screening of human ovarian carcinomas shows that the prediction of sensitivity to a cytotoxic agent is only possible in 64%. Prediction of drug resistance, however, seems to be possible in 95%. The number of patients that profit from the HTSCA seems to be only less than 10%. Our investigations describe the influence of various hormones and antiestrogens on the colony formation of human ovarian carcinoma cells. Tamoxifen and his major metabolite 4-hydroxy-tamoxifen were the most active agents. Both compounds inhibit the colony survival (70% at pharmacological concentrations) of 60% of the screened ovarian carcinomas. A significant correlation to the quantitative level of estrogen or progesterone receptors could not be proved. Colony formation of ovarian carcinoma cells was compared in the HTSCA as described by Hamburger and Salmon and in a methylcellulose-monolayer system. Our results show that the colony formation corresponds to the results of the original HTSCA: Cloning ovarian carcinoma cells in the methylcellulose-monolayer, however, seems to be technically easier and faster.

On serum albumin agar (bovine albumin) with initial pH-values of 5.0-6.0, Trichophyton rubrum showed a yellow pigmentation, and on the same medium with an initial pH-value of 7.0, a red pigmentation. Strains of Trichophyton mentagrophytes have never shown pigmentation until now, The scarce growth (submerged) of T. rubrum on serum albumin agar is associated with a pigment formation that may be used for diagnostic purposes. It could be read within 3-7 days. Serum albumin agar with the initial pH-value of 5.0 was introduced in 1964 for the detection of the strain-specific proteolytic activity of Candida albicans.

This paper deals with 1) Analysis of the agar droplet technique for viable bacterial counts with respect to a new technical aid (Colworth DROPLETTETM); 2) Comparison of the results obtained from two conventional plate count techniques and the agar-droplet method; 3) Examples for the practical use of this new technique. As a helpful aid for the agar-droplet technique there now exists an apparatus (Colworth DROPLETTETM, Fig.1) which facilitates dilution and dispension of bacteria containing agar, as well as counting of colonies grown in agar droplets. Precision and reproducibility of the diluter/dispenser was found to be within the limits of the usual sampling error (Tab.1, Fig. 2, Fig. 3). The visibility of colonies grown in agar droplets is improved by a ten-fold enlargement on the ground glass screen of the viewer (Fig. 7). In order to obtain droplets of equal size a standardised dropping-technique is required. The fluid agar must not exceed a constant temperature of 50 degrees C as otherwise four of the five species tested (Staph. aureus, E. coli, Kl. aerogenes, Ps. aeruginosa and Enterococci) were significantly reduced in number during the manipulation (Fig. 4, Fig. 5). Agar droplet technique, flooding technique and pour plates gave similar results with gram-positive and gram-negative bacteria from medical routine materials. Comparing the arithmetic means, viable counts of Staph. aureus were slightly higher from pour plates while E. coli and Kl. aerogenes gave the highest counts on flooded plates (Tab. 8-11). All of the three methods produced relatively too low counts when the number of bacteria per sample surmounted 300. Counts below 10 allow only a very poor estimation of the actual number of bacteria (Tab. 12). The variability of droplet counts with bacterial numbers higher than 25 was less then the one of corresponding plate counts (Tab. 14-16). Significant savings in materials, labour and incubator space are made with the agar droplet method. As examples for the practical use of the new method the results of the kinetics of thermally inactivated as well as of growing bacteria are presented.

Experiments with 5 commercial- and 4 testpreparations of Metachrome Yellow have been conducted. Results of this investigations show that the value of Gassners Medium is depending on the quality of the inhibitory substance. The microbiologically active substance (inhibition of grampositive bacteria and prevention of swarming of Proteus) was chemically identified as "Beizengelb GT Color Index 14025" correlating with CI Mordant Yellow I. Test sample II of CHROMA-GESELL-SCHAFT, STUTTGART is recommended as the best "Metachrom-Yellow for preparation of Gassners-Medium Now. Presumable this medium was modified repeatedly after its introduction in bacteriology in 1918 by Gassner. This can be an explanation for the different evaluations of Gassners medium and also for the numerous experiments which have been conducted to modify the medium. Indentity control of chemicals used in microbiology is done by thin layer and paper chromatography. This control should be done in cooperation with chemists more frequently than before.

Geliperm is a synthetic skin substitute, consisting of polysaccharid-polyacrylic plates. It is available as a soaked or a dried form (Geliperm dry). Geliperm dry can be soaked in antibiotic or antiseptic solutions. The in vitro inhibition of bacterial growth has been measured. The optimal concentrations have been evaluated. Geliperm dry soaked in antibiotic or antiseptic solutions can be used in the treatment of burns, but does not replace early excision of burned tissue or infected necrosis.

In vitro effects of 2 water-soluble prednisolon-derivatives on 10 Candida albicans and 10 Candida tropicals species were investigated. Tests were performed during resting and proliferation phases. Changes of cell metabolism were measured by O2-consumption by the Warburg technique. With increasing corticosteroid concentrations (10-10000 gammaml) a dose dependent increase of cell respiration was found with and without addition of nutritive substrates. Even high concentrations of corticosteroid did not cause an antimetabolic effect. The tests did not yield different results for the two Candida species examined.

At least 4 different colony form of Clostridium perfringens on the surface of yeast extract blood agar after overnight incubation were demonstrated. A: glossy colonies with entire margins, mostly surrounded by narrow zones of complete hemolysis and a much wider zone of incomplete hemolysis (colonies typical for C. perfringens (Fig. 1), B: dwarf colonies, similar to A, but very small (Fig. 2), C:rough colonies slightly raised with lobate margins (Fig. 3-4), D: flat colonies with irregular surface and filamentous margins (Fig. 5). Three strains out of 126 gave rise to glossy and rough colony forms (Fig. 6).

In the Institute of Bacteriology of Allgemeines Krankenhaus St. Georg, Hamburg, all clinical specimens received (except stools, sputum, and vaginal swabs) have been studied for the presence of anaerobians since 1947. More than 25 years' experience has convinced the authors that not infrequently, non-sporogenic anaerobians occur as infectious agents. Statistical data compiled for the period 1956-1972 revealed that from a total of 71,973 specimens contaminated with bacteria, 7,047 (9.8%) were containing non-sporogenic anaerobians. Pure anaerobic cultures were obtained in 2.404 cases (3.3%) and mixed cultures of aerobic and anaerobic bacteria in 4,643 cases (6.5%). The pathogenic importance was revealed by identifications from osteomyelitis cases: 11-13.7% pure cultures and 17% mixed cultures (with aerobians). Also in cases of total endoprosthesis of complicated course they were detected in up to 23%. On account of the frequent cultures of non-sporogenic anaerobians obtained from clinical specimens, the authors demand a routine analysis of all clinical specimens for the presence of anerobians...

The aim of this study is to check the clinical relevance of a new cultural method for the detection of urinary tract infection especially in urine samples containing residue of antimicrobial agents. The new procedure concerns a urine collecting and cultivating cup (UCCC Biotest Serum Institute), containing a recovery agar (RA5) with incorporated chemotherapeutica antagonists. The efficiency of the UCCC is compared with the familiar dip slide coated with cystein lactose electrolyte deficient (CLED) agar and MacConkey agar. A collective of 305 children is considered in this study. The investigation was carried out before starting, three to five days after starting and three to five days after stopping the chemotherapy. The highest correlation between the microbial count in urine samples and the whole clinical diagnosis was achieved with RA5. The lowest correlation was attained with MacConkey agar. With CLED agar a good correlation was determined before starting therapy, a modest correlation during therapy and very good correlation after stopping therapy. Regarding relapses and reinfections the detection quote of relevant bacteriuria during therapy amounted to 90% as RA5 was used, 62% with CLED agar and 34,5% with MacConkey. RA5 proved very useful for follow-up purposes, especially during treatment with antimicrobial agents and may be considered as a susceptibility testing in vivo.

In earlier publications [1-3] we reported on the retardation and protective effect of insulin-agar-embeddings in triglyceride suppositories by in vitro and in vivo tests on rabbits. The discovered effects were visually followed by gammascintigraphic test of adequate rectally applied 131I-insulin-specimens in the rectum and thyroid gland and, in relation with the glucose lowering course, the liberation, distribution and bioavailability of the immobilized hormone was illustrated.

The in-vitro and in-vivo liberation of insulin from embeddings in polymeric matrices was investigated dependent on the charging degree, the particle- and pore size, respectively, of the granules and the dissolution behaviour of the hormone. Polyacrylamide, agar-agar, dextrane and Sephadex G-100 were used as ground-mass. These polymers are characterized by a good swelling and a high binding capacity. If these properties quality them for insulin was investigated in model experiments. Information concerning the obtained retention effects of the matrix mould were produced by photochemical methods (application of insulin against citrate phosphate buffer; absorption region of 230 to 320 nm). The in-vitro effects yielded could be confirmed by means of representative in-vivo studies in eumetabolic insulin sensitive rabbits.

In 1946, DIENES observed that non-identical Proteus-strains, when swarming towards each other, were froming distinctly demarcated lines ("DIENES' phenomenon", demarcation (=AGL) phenomenon). Strains of the same origin were amalgamating without demarcation. In 1970, STURDZA studied this phenomenon and commented on its relevance for the epidemiology of nosocomial Proteus-infections. An increased number of Proteus-infections in Berlin was the reason that this procedure was tested for epidemiological purposes. Approx. 300 Proteus mirabilis-strains, tested on normal meat fluid agar, could be divided into 52 AGL-groups. When tested by several investigators, the coordination to any AGL-group seemed to be very subjective. Consequently, a DNase-agar with o-toluidinblue as an indicator, as had been mentioned by CHAMBERS in 1975, was used in order to give a more exact demonstration of AGL. This resulted in a reduction from 52 to 42 AGL-groups. Another 140 newly isolated Proteus-strains belonged to the 42 known as well as to another 42 new AGL-groups. Whether these 84 AGL-groups possess the constancy which is imperative for practical purposes, is however, still rather doubtful.

Bacteria have been found to grow differently at contact sites to both organic and anorganic solids as on pure agar media. Of 16 ad hoc selected bacterial strains, the following species (arranged in decreasing order) responded with stronger colony formation: Bacillus subtilis, B. cereus, Streptococcus sanguis, S. saprophyticus, S. faecalis, Escherichia coli, Micrococcus flavus, Actinomyces viscosus, Veillonella sp., Enterobacter liquefaciens, Yersinia enterocolitica. Lactobacillus casei behaved neutral. Proteus vulgaris, Y. enterocolitica and Chromobacterium violaceum grow on certain media only in the presence of solid particles. The yeasts Endomyces lactis, Saccharomyces cerevisiae, Rhodotorula mucilaginosa and Cryptococcus nigricans did not respond to solid particles during colony formation. The kind of protein-animal (meat) or vegetable (soy beans)-did not influence the behaviour of the microorganisms in these experiments.

In this paper studies for the standardization of the estimation of lysozyme in low concentrations concerning the lysoplate technique are reported. The influence of the conditions of diffusion, the concentration and the age of the bacteria as well as the judgement of different pictures of lysis and contrast resp. have been measured and compared. Sufficient results have been obtained with "Purified agar" (Difco) in a concentration of 0.9% and with living, 48 h old strains from Micrococcus luteus. After this a mixture of the bacteria in a concentration of 2.75 x 10(8)/ml with 5 ml "Purified agar" at 60 degrees C can be recommended. Using conditions of incubation with 50 degrees C and a final time of 4 h lysozyme can be estimated certainly with a sensitivity of 1 microgram/ml.

The number of chlorine-impaired E. coli organisms obtainable with the aid of the membrane-filtration-Endo-agar-method is so reduced that this method cannot be considered equivalent to liquid enrichment. Notwithstanding the well documented difficulties that arise from differences between batches of the same filters e. g. from problems to assure their standardization, the main obstacles do not stem from the questionable suitability of membrane filters but from the toxicity of the Endo-agar. The use of lactose-pepton (L.P.)-broth (German Standard Methods 1971) equally does not lead to satisfactory results if compared to the use of casein-soya (C.S.)-broth.

Not less than 1 nmol of methionine and phenylalanine were detected as fluorescent spots on agar plates with o-phthalaldehyde reagent under UV light. Microorganisms were grown on thin-agar-layer coated filter papers placed on nutrient agar plates, and then transferred onto new plates lacking nutrients by moving the papers. After the background amino compounds were removed by the diffusion to the bottom plates, the paper cultures were moved and incubated on assay plates containing N-acetylmethionine or N-acetylphenylalanine. The amino acids formed around the colonies were visualized by the o-phthaladehyde procedure to indicate aminoacylase activity of microorganisms. The substrate-and stereospecificity of the enzyme was shown for some strains on the agar plates by this procedure.

Since in some European countries the activity of antimicrobial substances are assessed on Disc-Sensitivity-Test (DST)-agar, routinely, it has been investigated whether and under which conditions Fosfomycin might be tested on DST-agar with the agar-dilution and -diffusion technique. A total of 320 strains representing 7 species were used as teststrains, and Mueller-Hinton (MH)-agar was employed as reference medium. On DST-agar the MIC-values were increased for some genera like Klebsiella by a factor of 128, a fact that was explained by the sixfold concentration of antagonistically acting Phosphate in DST-agar. Addition of glucose-6-phosphate (G-6-P) enhanced the sensitivity towards Fosfomycin only with some species. As the endpoint of growth is difficult to determine on DST-agar its use for agar-dilution tests with Fosfomycin can not be recommended. For agar-diffusion tests, however, this medium may be used provided that a thin film of growth or single colonies within the inhibition zones are being disregarded and that the disc content is increased from 50 microgram as being usual at present to 100 or 200 microgram. Diameters of inhibition zones that were obtained with such discs on DST-agar correlated very well (r = --0,89 und --0,93, respectively) with MIC-values derived from agar-dilution tests on MH-agar (+ G-6-P). With discs containing only 50 microgram no inhibition zones are formed by strains that should still be classified as "sensitive" (MIC: 8--32 microgram/ml).