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Optical coherence tomography angiography (OCT-A) represents the most recent modality in retinal imaging for non-invasive and depth-selective visualization of blood flow in retinal vessels. With regard to quantitative OCTA measurements for early detection of subclinical alterations, it is of great interest, which intra- and extra-ocular factors affect the results of OCTA measurements. Here, we performed OCTA imaging of the central retina in 65 eyes of 65 young healthy female and male participants and evaluated individual physical fitness levels by standard lactate diagnostic using an incremental maximal performance running test. The main finding was that OCTA measurements of the foveal avascular zone (FAZ) area were associated with physical fitness. Using multivariate regression analysis, we found that running speed at the individual lactate threshold, a marker strongly associated with aerobic performance capacity, significantly contributed to differences in FAZ area (β = 0.111, p = 0.032). The data indicates that smaller FAZ areas are likely observed in individuals with higher aerobic exercise capacity. Our findings are also of interest with respect to the potential use of retinal OCTA imaging to detect exercise-induced microvascular adaptations in future studies.

The ability of selected manganese peroxidase (MnP) yeast strains, isolated from the mixed liquor of an activated sludge bioreactor treating melanoidins wastewater, was investigated in this work, aiming to examine the degradation potential of melanoidins, in the presence or absence of nutrients. Ten yeast strains were initially isolated from the mixed liquor; four yeast strains (Y1, Y2, Y3 and Y4) were selected for further studies, based on their tolerance towards synthetic melanoidins (SMs) degradation and MnP activity onto solid agar medium. The Y1 strain exhibited almost 98% homology to Candida glabrata yeast, based on 28S rRNA identification studies. During experiments carried out using SM at 30 °C, the four isolated yeast cultures showed a noticeable organic matter reduction and decolorization capacity reaching up to 70% within 2–5 days. However, the corresponding yeast cultures grown in glucose peptone yeast extract medium using real melanoidin wastewater at 30°C showed lower organic matter and color removal capacity, reaching about 60% within 2–5 days. Nevertheless, it was found that the removal of real and synthetic melanoidins could be carried out by these strains under non-aseptic conditions, without requiring further addition of nutrients.

Fractionation of stable carbon isotopes upon degradation of trichlorobenzenes was studied under aerobic and anaerobic conditions. Mineralization of 1,2,4-trichlorobenzene by the aerobic strain Pseudomonas sp. P51 which uses a dioxygenase for the initial enzymatic reaction was not accompanied by a significant isotope fractionation. In contrast, reductive dehalogenation by the anaerobic strain Dehalococcoides sp. strain CBDB1 revealed average isotope enrichment factors (ε) between -3.1 and -3.7 for 1,2,3- and 1,2,4-trichlorobenzene, respectively. The significant isotope fractionation during reductive dehalogenation would allow tracing the in situ biodegradation of halogenated benzenes in contaminated anoxic aquifers, whereas the lack of isotope fractionation during aerobic transformation limits the use of this approach in oxic environments. © 2004 Published by Elsevier B.V. on behalf of the Federation of European Microbiological Societies.

Rumen fluid from sheep (non adapted to glycerol) was incubated up to six hours under anaerobic conditions with buffer and mineral solution. Wheat starch was added as substrate in an amount of 1g DM per vessel. Glycerol was additionally admitted to rumen fluid in amounts of 5 to 50% of starch. Carrier-free 14C-glycerol (1.3-labelled) or 15N-labelled NH4Cl were added to different incubation vessels. The disappearance rate of glycerol depended from the amount of added glycerol and incubation time. More than 90% of glycerol disappeared in 2 hours (5% addition), 4 hours (10% addition) and 6 hours (15 to 25% addition) respectively. The sum of volatile fatty acids elevated significant with a higher glycerol addition and 6 hours incubation time. The concentration of propionic acid increased also in dependence of the added glycerol amount and the longer incubation time. The proportion of acetic acid to propionic acid changed from high values (3.5 to 4.0, without glycerol) to the lowest value from 2.5 after 6 hours incubation time and 25% glycerol addition. The most radioactivity of added 14C-glycerol was found in propionic acid and only up to 11% in CO2. 14C-radioactivity was not detected in methane, lactic acid and acetic acid respectively. The 15N-labelling of TCA-precipitable N-fraction was not influenced by glycerol supplementation but the 15N-incorporation in the bacterial nitrogen fraction was lower in the vessels with glycerol.

We investigated the opportunistic pathogen Candida albicans in a continuous flow culture with regard to particular growth conditions. Germ counts of only 10(7) cfu/ml were obtained in a steady state of an anaerobic culture. In a parallel experiment with aerobic conditions excessive growth occurred and the invasive forms of Candida, i.e. germ tubes and pseudomycelium, also developed. Neither by different carbohydrates and concentration of nutrients in the culture medium nor by changing the flow rate the growth of Candida could be influenced. Excessive overgrowth was triggered by a sufficient oxygen supply.

From 1990 to 1992 we carried out 158 Conconi-Tests on children aged from 7 to 15. Of these tests 128 were carried out on the 400 m-track, and further 30 were Conconi-Intervall-Tests (Probst-Test). The testing was done on the members of the Swiss Figure-Skating Team, on the best runners of the Volksbank Grand Prix St. Gallen 1991/92 and on the youngest girls and boys of the Athletic Club Brühl St. Gallen. 89 tests were performed on girls and 69 tests on boys. In 84% of all cases (133 tests) the results were open to unambiguous interpretation, and were determined by the anaerobic threshold, 14% (22 tests), however, could not be clearly interpreted or had to be done again, and in 2% of all cases (3 tests) the results delivered no analysable information. In the results we only considered the 133 tests where clear interpretation was possible (114 from 128 Conconi-Tests, i.e. 89%, and 19 from 30 Probst-Tests, i.e. 63%). Thus we achieved the first aim of our research, which was to investigate the feasibility of carrying out Conconi-Tests on children and analysing the subsequent results thereof (with very interesting threshold results). From this, it is hoped, that norm data can be established, on which the anaerobic threshold and the threshold pulse of children active in sports can be based. At this point it must be stated that the classical Conconi-Test was found to deliver data easily and clearly interpretable, while the Intervall-Test was less easily analyzable.(ABSTRACT TRUNCATED AT 250 WORDS)

The survival of two genetically engineered E. coli strains (L+, CAG+) compared to that of 4 control strains (N0, K12, L-, CAG-), was investigated in drinking water, surface water, sewage and soil under different conditions. Both genetically manipulated strains are able to produce Prourokinase, an anticoagulant. It was found, that all strains died off inspite of high inoculated bacterial densities. In drinking water, no bacteria could be recultivated immediately following inoculation. Upon inoculation in surface water, the genetically manipulated strains L+ and CAG+ were more sensitive than the other strains. The same was found for sewage under aerobic conditions, whereby, the control strains N0 and K12 as well as the wild-strains of the genetically manipulated organisms, L- and CAG- survived the whole experimental period and kept their numbers at a level between 100 and 1000 CFU/ml. Under anaerobic conditions, a die-off of all tested strains was similarly registered with time. The influence of the autochthonous microflora of sewage water could be documented in that, under these conditions, all test strains survived the whole experimental period of 31 days with the exception of the genetically manipulated strain CAG+. In soil experiments, it was found that the humus-rich garden soil was more effective in eliminating the E. coli strains than sand. The antagonistic effect of the autochthonous soil microflora was only clearly seen in experiments with garden soil. However, these results did not meet the expectations for the two CAG strains, for which a longer survival period had been previously established for in nutrient rich soil. In contrast to the E. coli control strains N0 and K12, the two L strains and the CAG+ strain survived the whole test period of 36 days. It can be concluded that under these simulated environmental conditions, all tested strains of E. coli die off more or less in a short period of time following inoculation with the autochthonous microflora of environmental samples.

Niridazole which is chemically related to metronidazole is endowed with much better antibacterial activity. First, several genera of aerobic bacteria, such as Salmonella and Escherichia, are susceptible to niridazole, whereas metronidazole is completely ineffective. There exist, however, some particular strains which are naturally resistant to niridazole. The in vitro activity of niridazole is still increased, if these facultative anaerobic bacteria are tested under anaerobic growth conditions. Second, niridazole has a higher in vitro activity against anaerobic bacteria, such as Bacteroides spp., Clostridium spp., Fusobacterium spp. and Peptococcus sp., than metronidazole. Extremely low MIC values of niridazole were found ranging from 0.0037 to 0.06 microgram/ml. Propionibacterium acnes, which are resistant to the action of metronidazole, are also relatively resistant to niridazole.

Streptococcus salivarius synthesizes extracellular polysaccharides (EPS) from saccharose under aerobic and anaerobic conditions. Under aerobic conditions primarily soluble fructanes are formed. There are no differences between the EPS synthesized by r- and s-forms under aerobic conditions; anaerobically the s-forms produce more EPS and more fructane than the r-forms. As compared to streptococcus mutans, the streptococcus salivarius produces considerably more fructane and insoluble glucane under the conditions used.

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 construction, workwise and handling of a system for cultivation of bacteria to follow up gas production is described.

In 18 out of 39 strains of E. corrodens twitching motility was observed. Spreading colonies were associated with this kind of motility.

Bacteriological examinations of decubitus ulcers were performed in 34 geriatric patients. A total of 179 wound swabs were analyzed for aerobic and anaerobic bacteria. The decubitus ulcers were divided into three groups according to wound healing: group A with progressive worsening, group B, stationary, and group C with healing within 10 weeks. The aerobic bacteria isolated from the three groups were significantly different (p less than 0.0001). In group A Pseudomonas aeruginosa was isolated in 88%, enterococci in 73% and Providentia in 34%, whereas in group B staphylococci were found in 69%, enterococci in 62% and E. coli in 32%. In group C staphylococci dominated with 91%, followed by enterococci (51%) and E. coli (25%). Anaerobic microorganisms were significantly (p less than 0.01) more frequent in decubitus ulcers with poor healing tendency (group A and B) than in healing ulcers (group C). These results suggest that bacterial growth on decubital ulcers significantly influences decubital ulcer healing. Furthermore, bacteriological examinations are of prognostic value and the results should be considered in treatment.

Vaginal swabs obtained from 100 IUD-users were examined bacteriologically. Fifty-one women had vaginal discharge and 49 women used as control group had no complaints originating either from the IUD or from the genital tract. In the group of IUD-users with vaginal discharge the number of bacterial isolates was higher and the cultures were more diversified. The nulliparous patients in this group exhibited more anaerobic cultures than the IUD-users without discharge. The significance of vaginal discharge in IUD-users is its function as a pool for pathogenic bacteria which may provoke and/or maintain inflammatory diseases of the female genital tract. IUD-users with vaginal discharge do therefore need not only bacteriologic diagnosis, but also consequent treatment of the discharge.Examinations for vaginal bacteria were given to 100 IUD users. 51 of the patients had fluor vaginalis (32 nulliparae), and 49 of the patients did not have fluor vaginalis (19 nulliparae). In 87 cases, potentially or definitely pathogenic bacteria were found. Anerobic bacteria colonies tended to occur more often among the nulliparae than among the multiparae. Bacteria were found slightly more often among the patients with fluor vaginalis, as was an increase in the diversity of the bacteria. IUD users with fluor vaginalis should be treated in order to avoid possible pelvic inflammation of the genital tract.

We analysed a total of 36 strains of the obligately anaerobic Bacteroides species B. vulgatus, B. fragilis, B. thetaiotaomicron, and B. distasonis to test their faculties to metabolize chenodeoxycholate. For experiments with growing cultures, we used a synthetic medium with inorganic salts, glucose, citrate, amino acids, vitamins, and hemin. The same medium, but without amino acids and vitamins was used for experiments with resting cells, incubated aerobically. After preincubation in a medium containing bile and deoxycholate, we observed that 26 strains of 35 (74 per cent) could degrade this bile acid, when cultivated anaerobically, compared to 30 strains of 36 (83 per cent), when incubated aerobically. To sum up the number of active strains, there are 32, corresponding 89 per cent. With the exception of two strains, which formed two transformation products, all active strains formed one degradation product only. All strains but one, active when cultured anaerobically, belong to the species B. fragilis and B. thetaiotaomicron. As can be seen by the results of aerobic incubation most strains of the species B. vulgatus posses the degradative activity, found inactive, however, under anerobic conditions. We therefore suppose that its regulatory mechanism is different from the other species. Thin-layer, gas chromatography, and combined gas chromatography-mass spectrometry were used for the identification of transformation products. With these methods, we were able to demonstrate the bacteria to metabolize chenodeoxycholate to 3 alpha-hydroxy-7-oxo-5 beta-cholanoate, either if growing anaerobically or incubated aerobically. The second degradation products of two strains, found in traces or as by-product, could not be identified on account of minor amounts.

In 24 patients (aged from 5 to 21 years) afflicted with the tetralogy of Fallot and in 11 healthy subjects of the same age, the authors studied, using correlation and spectrum analysis, the coupling and the vibrational behaviour of modulated oscillations (in a rhythm of ca. 1 min.) of some psychophysiologic functions (heart and respiratory rates, blood pressure, sensomotor reaction times, short-time memory for ten-digit numbers) as expression of the central nervous coordination. The examinations were performed when the individuals were in the lying position, in the erect position and again at rest, during 10--30 min. In the subjects afflicted with the tetralogy of Fallot, the degree of synchronization or coupling (35%) was significantly lower than in the control subjects (65%). The decrease in the degree of coupling under orthostatic load was significant (P = 0.05) only in in the patients. One year after causal correction, the degree of coupling was normal (63%). From more than 400 autocorrelation functions and performance spectra (calculated to verify frequency and performance) it was deduced that the mean cycle of oscillation of the 1-minute rhythm was significantly shorter in the pre-operative state than in the postoperative state and in the control subjects. A change from the lying to the erect position manifested itself by a non-significant tendency towards period extension. The frequency deviations occurring in case of cyanotic vitium are discussed as an expression of the overall frequency behaviour of the oscillations which are continuously generated in coupled metabolic multienzyme systems, e. g., in case of anaerobic energy generation.

The wastewater pretreatment plant of Braunschweig works as a conventional, one step activated sludge plant without primary settling tanks. There were about 37,000 m3 per day of effluent during our investigations. During some months daily quantitative determinations of salmonellae were performed in the raw wastewater, in the activated sludge, and in the effluent. The mean concentrations of salmonellae were in the raw wastewater 2 X 10(5)/l and in the effluent after 11h of aeration and then settling 2 X 10(4) cells/l. The concentrations of salmonellae varied about the factor 10(3) (limits 10(2) to 10(5)). A small peak in the spring, a big peak in the late summer, and a week pattern were observed. The most salmonellae were adsorbed to unsoluble flocs of sludge, about 30-35% of the salmonellae only were found freely in the water and from that about 60% were concentrated round the flocs. Therefore, one step of settling removes about 90% of all salmonellae. In generally terms, the settling seems to be the most important step of removal of salmonellae from wastewater. Furthermore, the rate of removal is depending of the concentration. High concentrations of salmonellae cause a strong reduction and conversely. An immediate removal of salmonellae was observed in about 60%, however, there was a propagation of salmonellae in 30% of all samples, especially under conditions of low aeration, in an anaerobic environment, respectively.

By means of the Warburg technique, whether and to what extent microorganisms of the human plaque can metabolize xylitol under both aerobic and anaerobic conditions was studied, and the results were compared with those for saccharose. Under the chosen test conditions, this sugar alcohol was metabolized, if at all, in negligibly small traces only, during eight hours.

S. mutans OMZ 176 produced from mono-, disaccharides and hexitols in microbiological culture up to the log. growth phase different amounts of acid. Lactate was the gas chromatographically analyzed prevailing end product. Microbial suspensions of the same living mass prepared from the cultures produced homofermentatively lactate from glucose and sucrose whereas all other substrates (galactose, lactose, sorbitol, mannitol) were turned over partial heterofermentatively.

26 strains of obligate anaerobic bacteria, which had been isolated from clinical specimens, were tested for their survival on artificially contaminated cotton swabs after storage. All strains could hardly if at all be cultivated, if the cotton swabs had been stored in empty test tubes at 4 degrees C for 48 hrs. In contrast to that it was possible to cultivate all strains without significant reduction of their number from swabs, which were stored at 4 degrees C for 48 hrs in test tubes containing Stuart's transport medium. The necessity of an improvement of techniques and transport-methods to isolate anaerobic bacteria is discussed. The use of a special transport medium is recommended as an important aid to the early recognition of anaerobic infection.

Current methods for isolation and identification of obligately anaerobic bacteria are laborious and time-consuming. Direct gas-liquid chromatography of purulent and serous specimens for short-chain fatty acids allows a presumptive diagnosis of anaerobic infection. Good correlation was found for the cultural recovery of anaerobic bacteria and the presence of propionic acid in concentrations of greater than or equal to 1 muMol/ml, isobutyric, butyric, isovaleric, valeric, isocaproic and caproic acid at greater than or equal to 0.1 muMol/ml, and succinic acid at greater than or equal to 2 muMol/ml (either as single acids or in combination). Specimens yielding no anaerobic bacteria in culture contained only acetic, lactic and small amounts of succinic acid, but none of the volatile acids.

A CO2-dependent mutant of Salmonella typhi was isolated from anaerobic but not from aerobic blood-cultures of two patients with typhoid fever. Both patients diseased after return from their home country Turkey. The strains developed in a CO2-enriched atmosphere and under anaerobic but not aerobic culture conditions. This property remained stable during 20 subcultures. The fermentative and serological pattern was identical with S. typhi T2. Both strains were of lysovar E1a.

The results of 42 fecal flora analysis of healthy adult men were compared by using a newly developed method and an old conventional method. Statistical estimate indicate, that with the new method the total counts and the counts of bifidobacteria, catenabacteria (eubacteria and anaerobic lactobacilli), peptostreptococci, and clostridia (except Cl. perfringens) as well as the occurences of peptostreptococci and spirillaceae were significant higher than with the use of the old method. On the other hand the counts and occurences of bifidobacteria, veillonellae, Cl. perfringens, Megasphaerae and aerobes were similar with both method. With the new method the total counts of feces of healthy adult men nubmered 1-2 X 10(11) per g wet weight, and fastidious anaerobes, such as bacteroides, catenabacteria and peptostreptococci, were always occurred as predominant flora. The results suggest that the conventional anaerobic jar method is inadequate for the isolation of fastidiuos anaerobes and indicate that the use of modified medium 10 in combination with strict anaerobic technique is necessary for the analysis of fecal flora.

The growth promoting properties of seven commercially manufactured and two recently developed culture media are compared according to a standardized method. The study is carried out alternately without and with the addition of 10% fresh human blood to the culture media. The carefully selected test strains include 20 species of bacteria and 2 species of yeasts which represent obligatory aerobic, facultative anaerobic and obligatory anaerobic microorganisms with quite different nutritional and atmospherical requirements. The 9 tested media are good enough for the purpose of culturing nonfastidious bacteria. However, most of the commercially prepared media failed to detect small inocula of very fastidious microbial agents, especially when no blood is added. Collectively, thiol broth is the most noneffective medium. The last but one is thioglycollate medium. Three culture media based on brain heart infusion formula prove to be effective. Those are the commercial brain heart dextrose and the two media recently developed by the authors, namely brain heart dipeptone (BHD) and brain heart dipeptone cysteine (BHDC). BHD is the most suitable medium for the detection of obligatory aerobic and facultative anaerobic fastidious microorganisms. BHDC detects anaerobic fastidious bacteria quite effectively. The other media, namely Columbia, trypticase soy, trypticase soy sucrose, and Rosenow are of limited value with regard to the detection of small inocula of fastidious microorganisms. The causes of the unsatisfactory results with different commercial media are discussed in detail. The authors point out to the possible use of hypertonic media in special cases. Properties that should be fulfilled by blood culture media are proposed.

The protective effect of low temperatures during irradiation on vitamin B1 and E levels in foods is not abolished by subsequent storage or heating. Egg powder irradiated at 1 Mrad in the presence of air and stored for 4 months at ambient temperature lost 68% of its thiamin content when irradiated at 20 degrees C, 33% when irradiated at -30 degrees C. Sunflower oil irradiated at 3 Mrad in the presence of air and subsequently heated for 1 hour at 180 degrees C lost 98% of its alpha-tocopherol content when irradiated at 20 degrees C, 65% when irradiated at -30 degrees C. Exclusion of atmospheric oxygen by packaging under nitrogen reduced the loss of alpha-tocopherol in irradiated (0.1 Mrad) rolled oats after 8 months of storage from 56 to 5% and the loss of thiamin from 86 to 26%. Vacuum packaging was equally effective during the first 3 months and somewhat less effective during the following 5 months. Packaging under carbon dioxide showed no advantage over packaging in air. Sensory evaluation of rolled oats, raw or cooked, 1 and 3 months after irradiation with 0.1 Mrad indicated no significant quality difference between unirradiated and irradiated samples packaged under nitrogen.

Metronidazol was employed in the endodontic treatment of 200 gangrenous teeth, with symptoms of acute and chronic periodontitis. In 50 cases aerobic and anaerobic microbiological cultivations have been performed. The number of the necessary treatments was less, symptoms of irritation in the periapical region could not be observed. The favourable clinical and microbiological results in the course of the Metronidazol treatment point to the role of the anaerobic microorganisms in connection with the inflammatory symptoms of the gangrenous pulp.

On the basis of model concepts on physical gas exchange a technique was developed for studying the complex interrelationships existing between the characteristics indicating the suitability of a particular material for ensilage and the specific local conditions for silage making at the farm and in a silo. (degree of anaerobic conditions). Conclusions were drawn as to quantitative relations existing between the thickness of the marginal layers of a silage stack that are subject to losses and the compaction of the silage material and the sealing of the silage top during the periods of filling and storage. On the basis of these considerations limits are given for minimum filling of a silo per day of ensilage as depending on the compactness of the consolidated fresh or wilted silage material. Data are given for silage losses at the edged of the silage stack.