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V Hingst

Publications and source records attributed to V Hingst.

At least 37 records · Page 2Linked to original sources
PubMed1992

[The determination of the discrepancy between the mathematically ascertained and experimentally provable efficiency of UV facilities for water disinfection].

Using three UV-plants of different technical designs for water disinfection, we studied the conformity between experimental germ reduction using standard test organisms and calculated UV-doses under various water flow conditions. Taking into consideration the style of construction of the UV-plants, the irradiation area and the layer thickness were used as constant parameters for dose calculations. This was also employed for the irradiation intensity, since the experiments were performed for a relatively short period compared of the life span of the UV-irradiators. Both exposure time and water transmission were employed as variable parameters in the dose calculations and experimental procedures respectively. The calculated UV-dose and experimentally obtained germ reduction values were comparatively the same for two of the three UV-plants studied. However, no correlation was observed between the reduction of E. coli and the corresponding calculated UV-dose values. Therefore, the calculated UV-dose values for any given UV-plant should be considered to be relative and by no means absolute values. We are of the opinion that within a certain range of water flow rate and transmission, antimicrobial effectiveness of different UV-plants should be demonstrated independent of dose values, technical and other construction characteristics. The applicability of the UV-plants studied is discussed.

Bacteria↗
PubMed1992

[The development of an enzyme immunoassay for the detection of the herbicide metolachlor in water samples].

Since December 1990, strict limits for pesticide content in drinking water have been in effect in the FRG. These limits have to be enforced and controlled regularly. Because the classical analytical methods, like GC/MS and HPLC are relatively expensive and complicated, concentration and clean up of the samples are necessary. Therefore, the significance of Enzyme Immunosorbent Assays has increased in environmental analysis. The topics of our research are synthesis of suitable Metolachlor conjugates for immunization and as coating antigen, as well as development of an Enzyme Immunosorbent Assay. The chloroacetanilide Metolachlor was coupled with an AMSA-Spacer on Sheep IgG and with AHT-Spacer on BSA. The epitope density was measured photometrically with TNB-derivate. Polyclonal antibodies were produced in white New Zealand rabbits. Metolachlor-AMSA-Sheep IgG conjugate was served as immunogen. The test is indirect and competitive. Microtiter plates are coated with the coating antigen (Metolachlor-AHT-BSA conjugate). In the next step the Metolachlor sample competes with the coating antigen for the antibodies. Detection of bounded antibodies is indirect with a peroxidase-labelled secondary antibody. The chromogenic substrates ABTS, TMB and OPD were tested. TMB showed the best qualities, fast turnover, as well as good and steady colour. Titer of serum and crossreactivity of other chloroacetanilide pesticides and their metabolites were tested. With the exception of Alachlor and Dimethachlor, no pesticide showed a high interaction with serum. Quantitative interpretation was done with the logit/log transformation, which allows comparison of different sera and test series. The antibodies are specific but the affinity is not good enough to detect the limits assigned by the "deutsche Trinkwasserverordnung". Raising the concentration, as is done in classical analytical methods, would solve the problems so that the test can be used as a screening test.

Acetamides↗
PubMed1991

[Elevation of the bacteriological content of milk of clinically unaffected lactating bitches of a canine research stock].

In the years 1987-1989 a bacteriological investigation of the milk was made in 44 clinically healthy postparturient bitches. In 30 animals bacteria most commonly isolated were staphylococci. 30.3% (40 samples) of the samples yielded pure cultures and 6.8% (9 samples) anacultures. Small numbers of bacteria were isolated in most of the samples; 67.4% showed moderate bacterial growth (less than or equal to 10(4)/ml sample). In vitro drug sensitivity tests revealed lincomycin, erythromycin and polymyxin B proved to be most efficient. Moreover neomycin, kanamycin and chloramphenicol showed low resistance rates while colistin sulfate and carbenicillin were less effective. A direct influence of lactiferous gland colonization with bacteria on mortality of puppies was not observed. With respect to clinical aspects, the application of antibiotics for sanitation of the lactiferous gland colonization with bacteria in clinically healthy bitches has to be considered carefully. However, for this the estimation of drug sensitivity tests is not satisfactory and should be completed by accurate bacteriological identification.

Animals↗
PubMed1990

[A rapid test procedure for the detection of B streptococci in the perinatal period].

At the Hospital of the Department of Gynaecology of the University of Heidelberg, a latex agglutination test (Strep B Patho Dx Test) was applied after extraction of antigens from amniotic fluid and gastric aspirate, parallel to the routine screening programme (vaginal and anal swabs) for maternal colonization with B streptococci. The latex agglutination test was applied in 1336 cases. Maternal vaginal colonization was detected in 14%, anal colonization in 17% of the cases. A comparison of the results obtained with the latex agglutination test and with conventional bacteriological procedures (no gradual bacteriology, incubation 48 hours) showed antigen identification in amniotic fluid in 54%, respectively 24%. In gastric aspirates a B streptococcal contamination was detected by bacteriology in 40% of cases, by the rapid latex agglutination test in 22%. If no streptococci were found in the mother, amniotic fluid or gastric aspirates were contaminated in 4% or 6%, respectively (agglutination test or bacteriology, respectively). With a sensitivity of approximately 50% and a specificity of 98%, the latex agglutination test proved superior to routine bacteriology. All clinically contaminated newborn (positive blood specimens) were clearly identified by this test. With this new latex agglutination test, a procedure is now available to detect B streptococcal contamination in newborns within less than half an hour, thus an intra- or postpartal antibiotic therapy can be applied early.

Anal Canal↗
PubMed1990

[Microbiological studies of the significance of natural and simulated water transmission in the evaluation of UV plants for water disinfection].

The efficiency of UV-irradiation for water disinfection was tested using an UV-plant with constant flow between 0.7 and 11.5 m3/h. Within the range of water transmission (254 nm) between 40% and 98% (1 cm), which naturally was found in tap water, water from the Neckar river and biologically treated sewage water in an amount of 96%, 78% and ca. 60%, simulation was performed by artificial addition of fluorescein to demineralized water. Data obtained show similar results for the reduction of E. faecium and C. albicans, which were used as test strains. The investigation show no major discrepancies in the range of transmission from 80-96%, which is relevant for tap water disinfection. Water transmission at 254 nm was confirmed as important factor for UV-irradiation. Also found suitable was fluorescein for simulation of the natural water transmission without affecting the test strains. Thus UV-sensitivity of test strains could be detected by combination of flow rate and simulated water transmission using fluorescein. P. aeruginosa and E. coli were found to be more UV-sensitive than S. enteritidis and S. marcescens. UV-resistance increased on the scale from E. faecium, S. aureus, M. luteus up to C. albicans. The efficiency of an UV-plant can be experimentally defined by a specific combination of flow rate (up to a certain amount) and water transmission. Thus the question can be answered whether and UV-plant is able to fulfill the specific requirements in use. These results, regarding the artificial variation of transmission values, are to be considered important for the specification of an additional measure of safety for minimal irradiation exposure times.

Candida albicans↗
PubMed1990

[Metastasis of bronchial carcinoma in the temporomandibular joint. Case report].

Within 35 years 1008 patients were treated that were taken ill in a malignant tumor of face, jaw and mouth. There was found in five patients a distant metastasis of a carcinoma in lower yaw. One case with metastasis in left mandibular condyle is being described. The diagnosis was found by using conventional X-ray examination, Computertomography and aspiration cytology.

Aged↗
PubMed1990

A quantitative test method for the examination of antimycobacterial disinfection procedures.

Various aspects of the test methods currently established in western industrial countries for the qualitative and to a certain extent quantitative measurement of the antimycobacterial efficacy of disinfection procedures have recently been increasingly criticized in the international literature. For this reason, a quantitative test method for suspension trials and carrier trials, which includes the test strain Mycobacterium terrae ATCC 15755, has been developed. Experience with the new methods has proved them easy to learn and to reproduce. Before the methods, presented here in detail, can be recommended to the German Society for Hygiene and Microbiology (Deutsche Gesellschaft für Hygiene und Mikrobiologie, DGHM) as official testing procedures, their acceptability should be tested in a multicenter study. Taking the results thus obtained into consideration, recommendations for the reduction factors required for the declaration of a safe antimycobacterial disinfection procedure should be made.

Colony Count, Microbial↗
PubMed1989

[The significance of the contamination of dental care articles. The results of a field study].

Permissible conclusions both from recent available literature and our own field-study results concerning the problematic nature of microbial contamination of dental hygiene articles and the resulting possible health hazard for the consumer can be summarized as follows: Manufacturing practices as are given in the basic instructions for production sites of the cosmetic industry, render a possible degree of microbial contamination. This largely rules out the danger of infection of the consumer upon acquisition of the dental hygiene product. Secondary contamination of these products, as inevitably is the case during use of dental hygiene articles, leads to microbial colonization especially of toothbrush bristles. The extent of this colonization depends at least partially upon the utilization age of the toothbrush. Also for this reason a toothbrush should be replaced by a new one after period of three months, six months at the latest and in all cases of inflammatory changes of the mouth and throat region. The contamination of both the glass or plastic container used for rinsing the teeth after brushing or for gargling can be held within certain limits by dry storage. Only in exceptional cases do mouthwashes show a small degree of contamination. Provided they contain antimicrobial substances, no therapeutically serviceable possibilities worth mentioning follow for the reduction of oropharyngeal flora. Microbial colonization of toothpastes as a result of secondary contamination following use is observed only in exceptional cases due to their preservative content. Significant germination of stagnated residual water in waterpicks often occurs, achieving germ counts up to more than 10(7) cfu per ml. Moreover, waterpicks can represent a biotope for Pseudomonas aeruginosa, and should be used neither by patients with open wounds or mucous membrane lesions in the oropharyngeal area, nor by patients with reduced immune resistance. Manufacturers of waterpicks are urged to impede or prevent the stagnation of residual water more effectively by introducing constructive improvements. Denture and retainer cleansing agents presently on the market display a sufficient antimicrobial effect within the frame of their application, however do not meet the standards set for disinfectants. Dental hygiene products are without relevance for the epidemiology of Legionnaires' disease.

Bacteria↗
PubMed1987

[The enzymatic degradation of formaldehyde by isolates of Pseudomonas aeruginosa].

The capacity of 12 Ps. aeruginosa-strains to enzymatically degrade Formaldehyde was tested. These strains, derived from environmental and patient samples, were previously passaged 25 times in increasing formaldehyde-concentrations, in a micromodification of the bacteriostasis test. The formaldehyde-degradation was detected photometrically with the sulfite-pararosaniline-method. Furthermore, in 4 of the 12 strains the activity of a formaldehyde dehydrogenase assumed to be the degrading agent was determined. The tested strains exhibited a markedly differing resistance to formaldehyde, some environmental isolates growing even at concentrations in the range of commonly used disinfectant solutions. The exponential growth phase of the inoculum and the reduction of formaldehyde-content coincided. The strains with the highest formaldehyde-resistance showed a formaldehyde-dehydrogenase activity higher by approximately a factor 100 compared with the rather sensitive ATCC-strain. This dehydrogenase activity, in addition to possible extra- and intracellular penetration barriers, could be a causal factor for an increased formaldehyde-resistance.

Aldehyde Oxidoreductases↗
PubMed1985

Evaluation of API 20 NE in routine diagnostics of nonfermenting gram-negative rod-shaped bacteria.

292 strains of non-fermenting Gram-negative rod-shaped bacteria were determined by standard methods and tested in a new commercial microidentification-system, the API 20 NE (api Biomérieux). A total of 282 (= 96,6%) strains were identified conformably; 130 (= 46,1%) after 24 h and 77 (= 27,3%) within 48 h. In 75 (= 26,6%) cases different conventional additional tests for determination to species level were necessary. The reasons for divergent results of 10 strains are discussed. The new microidentification system API 20 NE might be a simple and reliable tool in hand of the skilled medical microbiologist.

Alcaligenes↗
PubMed1985

[Differentiation of nonfermenting gram-negative human-pathogenic rod bacteria from sewage water].

In the present paper the examination of the new microidentification-system API 20 NE for clinically important nonfermenters is reported. The origin of all strains tested was non-clinical (sewage, tap-water, food-stuff and other environmental sources). One hundred thirty four strains were examined simultaneously in the API 20 NE and by standard tests. One hundred twenty three strains, which included 23 species could be identified conformably. Out of 11 strains, not or misidentified in the API-system only 2 could be classified to species level by conventional means, the remainder were diagnosed to genus level only. Causes are discussed. Our data suggest that the API 20 NE is also a useful aid in routine diagnosis in environmental hygiene for clinically important nonfermenters. It allows a short-time-diagnosis with a high degree of specificity and reliability.

Food Microbiology↗
PubMed1985

[Formaldehyde resistance to gram-negative aerobic rods from municipal sewage water].

In a municipal sewage works, a total of 30 sewage samples (19 from the inlet and 11 from the outlet of the sewage works) were analyzed for the quantitative and orientative qualitative content of microorganisms. With an incidence peak of the total bacterial count of greater than or equal to 1 X 10(6) cfu/ml in the inlet, both samples showed bacterial contents of 1 to 9 X 10(5) cfu/ml with use of MC agar and Endo agar. Fuchsin glistening colonies as well as the total bacterial counts on Sabouraud agar and Leifson agar as well as on kanamycin-esculin agar showed frequency peaks which were one power of ten lower. For pathogenic staphylococci, a distribution below the limit of detection (down to 9 X 10(3) cfu/ml) was found, and in a single case in the region of 10(4) cfu/ml. As a rule, the samples drawn from the outlet of the municipal sewage works showed values which were one power of ten lower than in the inlet. With admixture of formaldehyde in bacteriostatically active concentrations, colonies could still be cultured to a small extent with a final concentration of 0.03 weight % HCHO in the inlet, whereas values were below the limit of detection in all outlet samples. The differentiated Gram-negative aerobic rods were mainly representatives of the species Pseudomonas aeruginosa and Pseudomonas putida. In a modified quantitative suspension trial, only occasional Gram-negative rods in the inlet samples survived 30 min exposure to 0.5 weight % HCHO. In comparison, the results of the outlet samples showed a very much lower resistance to formaldehyde. The 11 strains isolated under these conditions could be classified under six species, including four Pseudomonas aeruginosa strains. Gram-negative rods which had previously tolerated a concentration of 0.12 weight % formaldehyde in the bacteriostasis revealed a raised resistance to formaldehyde only to an inappreciable extent under the conditions of the qualitative suspension trial. Overall, enhancements of resistance to formaldehyde such as we observed in isolates from hospital sewage could not be detected in bacterial strains isolated from the inlet or outlet of a municipal sewage works. The investigations carried out thus do not indicate that a quantitatively significant increase or a persistence of the resistance to formaldehyde is to be expected outside the actual hospital environment.

Drug Resistance, Microbial↗