Showing papers on "Typing published in 1986"

Paleoepidemiologic investigation of Legionnaires disease at Wadsworth Veterans Administration Hospital by using three typing methods for comparison of legionellae from clinical and environmental sources.

Abstract: Multilocus enzyme electrophoresis, monoclonal antibody typing for Legionella pneumophila serogroup 1, and plasmid analysis were used to type 89 L. pneumophila strains isolated from nosocomial cases of Legionnaires disease at the Veterans Administration Wadsworth Medical Center (VAWMC) and from the hospital environment. Twelve L. pneumophila clinical isolates, obtained from patients at non-VAWMC hospitals, were also typed by the same methods to determine typing specificity. Seventy-nine percent of 33 VAWMC L. pneumophila serogroup 1 clinical isolates and 70% of 23 environmental isolates were found in only one of the five monoclonal subgroups. Similar clustering was found for the other two typing methods, with excellent correlation between all methods. Enzyme electrophoretic typing divided the isolates into the greatest number of distinct groups, resulting in the identification of 10 different L. pneumophila types and 5 types not belonging to L. pneumophila, which probably constitute an undescribed Legionella species; 7 clinical and 34 environmental VAWMC isolates and 2 non-VAWMC clinical isolates were found to be members of the new species. Twelve different plasmid patterns were found; 95% of VAWMC clinical isolates contained plasmids. Major VAWMC epidemic-bacterial types were common in the hospital potable-water distribution system and cooling towers. Strains of L. pneumophila which persisted after disinfection of contaminated environmental sites were of a different type from the prechlorination strains. All three typing methods were useful in the epidemiologic analysis of the VAWMC outbreak.

Comparison of serogrouping and polyacrylamide gel electrophoresis for typing Clostridium difficile.

Abstract: A typing scheme for Clostridium difficile based on slide agglutination with rabbit antisera was previously described. It allows the differentiation of 10 serogroups designated A, B, C, D, F, G, H, I, K, and X. We studied the correlation between serogrouping and polyacrylamide gel electrophoresis (PAGE) of whole-cell proteins. A total of 202 isolates from different sources were analyzed by PAGE after ultrasonic disintegration of cells from an 18-h liquid culture and treatment with sodium dodecyl sulfate and 2-mercaptoethanol. A total of 21 different patterns were observed. The reference strains from the 10 serogroups showed different profiles. For each serogroup except A, the patterns obtained with the clinical isolates were identical to the patterns obtained with the reference strains. For the 48 strains belonging to serogroup A, 12 different profiles were observed. Five of these involved strains isolated from patients with antibiotic-associated diarrhea. Typing by sodium dodecyl sulfate-PAGE thus correlates with serogrouping. In addition, it allows discrimination within the heterogeneous serogroup A.

The evaluation of a phage-typing system for Listeria monocytogenes for use in epidemiological studies.

Abstract: Summary A typing system for strains of Listeria monocytogenes based on the lytic properties of 28 phages has been evaluated with a set of strains isolated in the UK and tested in a blind trial. The system was highly reproducible and discriminatory, and 64% of all the strains tested could be typed.

Geographic distribution of restriction types of Mycobacterium bovis isolates from brush-tailed possums (Trichosurus vulpecula) in New Zealand.

Abstract: DNA restriction endonuclease analysis was used for intra-specific typing of Mycobacterium bovis isolates from 83 brush-tailed possums (Trichosurus vulpecula) obtained between 1982 and 1984 from the three major regions in New Zealand with endemic bovine tuberculosis. All the isolates were found to be genetically very similar. Differentiation of the isolates into 33 restriction types was achieved by using high-resolution electrophoresis and the combined results from separate digestions with the restriction enzymes Bst EII, Pvu II and Bcl I. The typing system was entirely reproducible. Isolates of the same type were usually found in adjacent localities and were always limited to one of the three major regions. In some cases, isolates of the same type were found in both 1982 and 1984. The phenotypic significance of the small genetic differences identified between different isolates is unknown. The typing system will be useful for monitoring the transmission of M. bovis to other species and the future spread of different M. bovis types through possum populations.

Joint report of the Third International Workshop on Canine Immunogenetics. I. Analysis of homozygous typing cells.

Abstract: The Third International Workshop on Canine Immunogenetics involved 80 potentially DLA-D homozygous typing cells obtained from dogs of various breeds and submitted from five laboratories in Europe and the United States. Mutual reactivity of all cells was studied in mixed leukocyte cultures, and stabilized relative responses were used for analysis. Intralaboratory and interlaboratory comparisons of results suggest that a stabilized relative response of 30% represents an acceptable parameter for "typing responses" indicating phenotypic DLA-D identity of stimulator and responder cells. Using this criterion, 10 clusters of homozygous typing cells were defined and accepted on an international level, and they were assigned the specificities Dw1 to Dw10. At least six additional (provisional) specificities were recognized that were well characterized within individual laboratories but require additional testing before workshop specificities can be assigned. These data show that DLA-D typing is feasible and represents a useful tool in the genetic analysis of the canine major histocompatibility complex. Much work is needed to confirm the present results in family studies, to determine gene frequencies, and to analyze at a molecular level the antigens responsible for mixed leukocyte culture reactivity.

Immunoblotting to demonstrate antigenic and immunogenic differences among nine standard strains of Clostridium difficile.

Abstract: The epidemiology of Clostridium difficile-associated disease is being elucidated with the development of typing schemes for the organism. We recently described a new typing scheme based on the incorporation of [35S]methionine into bacterial proteins followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography. Nine standard strains were identified. We report here some observations on the antigenic differences among these nine strains when studied by immunoblotting. Type-specific rabbit antiserum was raised against each of the nine standard strains. Immunoblotting of the strains with these antisera demonstrated, in addition to the presence of shared, common proteins, a type-specific response with homologous antisera. When [35S]methionine-labeled C. difficile proteins were immunoblotted with homologous and heterologous antisera, both the immunoblots and the autoradiographs demonstrated the same strain-specific response. These strain-specific proteins, which have been so useful for epidemiological and typing purposes, were also immunogenic. Images

HLA Typing Using DNA Probes

Abstract: We discuss the genetic organization of the human major histocompatibility complex (the HLA region), and review recent advances in HLA typing achieved by analysis at the DNA level The use of HLA Class II DNA probes, labelled either with 32P or non–radioactively, has revealed polymorphisms not detectable with conventional serologic typing reagents These DNA polymorphisms, identified by restriction fragment length analyses, or by allele–specific oligonucleotide probes, have proved informative in transplantation tissue–typing, paternity determinations, and for disease susceptibility studies

Typing of strains of Staphylococcus aureus by Western Blot analysis of culture supernates.

Abstract: Summary Extracellular proteins produced by Staphylococcus aureus strains were examined by Western Blot analysis with blood donor plasma as a source of antibodies. Comparison of epidemiologically related strains showed strong concordance between plot pattern and phage type.

Phage-typing patterns and lysogenicity of methicillin -resistant strains of Staphylococcus aureus from Sydney, Australia, 1965-85

Abstract: Summary. Methicillin-resistant strains of Staphylococcus aureus isolated at the Royal Prince Alfred Hospital since 1965 were differentiated by phage-typing and by their lysogenic status. Most of these strains were isolated during two periods, 1965-72 and 1976-85. Nearly all of the strains isolated in the first period had one of four phagetyping patterns. Strains with each typing pattern carried two prophages; these eight phages were all different, as characterised by serological grouping and lytic spectrum. Lysogenisation of the non-lysogenic strain 1489 with each of these phages narrowed its phage-typing pattern; the typing pattern of the double lysogens was generally similar to and occasionally identical with that of the host strain that had yielded the pair of phages. In the second period, strains with one of five other phage-typing patterns predominated. Representatives of each of these carried the lysogenic phage C. The first methicillin-resistant strain carrying this phage had been isolated in 1974. The current methicillin-resistant S. aureus strains thus appear to form a distinct group that can be differentiated from those seen in earlier years.

Studies on the Serology of Flagellar Antigens of Yersinia Enterocolitica and Related Yersinia Species

Abstract: A total of 1242 strains of Y. enterocolitica , 104 strains of Y. frederiksenii , 95 strains of Y. kristensenii and 85 strains of Y. intermedia were serotyped with antisera against 56 O antigens and 19 H antigens according to the extended antigenic scheme of Wauters , and with additional antisera against 4 somatic and 19 flagellar antigens not previously described. H antigens of Y. frederiksenii, Y. kristensenii , and Y. intermedia turned out to be rather homogeneous without distinct subfactors. In these species the scope of identified serovars was narrow. Flagellar antigens of Y. enterocolitica were mostly composed of several subfactors, leading to a total of 117 serovars identified in the species. A number of cross-reactions between Yersinia H antigens were observed which could be avoided by absorption without significant lowering of the titre. Flagellar antigens of Yersinia were monophasic, and species specific. The antigens remained stable after storage in agar stabs and repeated subcultures. The epidemiological value of serotyping is demonstrated by strains from three different sources. It is suggested serotyping of Yersinia strains should be performed in three steps: — O typing of the prevailing enteropathogenic Y. enterocolitica serogroups in the medical routine laboratory; — O and H typing of Y. enterocolitica by National Reference Centres applying a typing scheme reduced to this species; and — O and H typing of Y. enterocolitica, Y. frederiksenii, Y. kristensenii and Y. intermedia by specialized International Centres using an extended typing scheme. The need for international standards comparable to those established for Salmonella is emphasized.

Typing of Herpes Simplex Virus with Synthetic DNA Probes

Abstract: Three single-stranded oligonucleotide probes, 22 bases long, homologous to unique regions of herpes simplex virus (HSV) types 1 (HSV-1) and 2 (HSV-2) and a region common to both were chemically synthesized with use of a modified phosphochloridite protocol. For hybridization experiments each probe was labeled with use of polynucleotide kinase and [gamma-32P] ATP to a specific activity of approximately 2 X 10(9) cpm/micrograms. Two hundred one clinical isolates of HSV (96 HSV-1 and 105 HSV-2) collected from vesicles in the mucocutaneous junction of the mouth or from the genital area were analyzed. There was a 99% (199 of 201) agreement between hybridization and monoclonal antibody typing; the two discrepant isolates of HSV-2 that were negative by monoclonal antibody typing were confirmed as HSV-2 by restriction endonuclease analysis. The probes detected between 10(4) and 10(5) HSV infectious units and from 150 to 600 HSV-infected Vero cells. No binding was detected between any of the three probes and isolates of cytomegalovirus, Epstein-Barr virus, and varicella-zoster virus.

Bacterial Agglutination and Polyacrylamide Gel Electrophoresis for Typing Clostridium difficile

Abstract: Bacterial agglutination and polyacrylamide gel electrophoresis (PAGE) were methods evaluated for typing strains of Clostridium difficile. A panel of four antisera, obtained by immunizing rabbits with washed whole cells of different strains of C. difficile, produced distinctive patterns of agglutination. Ethylenediaminetetraacetate (EDTA) extracts subjected to PAGE also produced distinctive protein profiles. Excellent correlation between the two methods was observed when geographically distant isolates were typed without knowledge of their clinical origin. Both typing methods should receive further evaluation for their value as tools for epidemiological studies.

An inhibitor typing scheme for Streptococcus uberis

Abstract: A typing scheme was used to test 15 strains of Streptococcus uberis according to their production of (P-type) and sensitivity to (S-type) bacteriocin-like inhibitory substances. Twelve of the strains were inhibitor producers and nine different P-types were detected. All of the strains were typable according to inhibitor sensitivity, ten different S-types being distinguished. Both the P-type and S-type designations of the strains were reproducible on repeated testing. By combination of P-typing and S-typing, highly discriminatory inhibitor 'fingerprints' of the strains could be obtained. This scheme would appear to have considerable potential for typing isolates of Str. uberis as an aid to investigations into the epidemiology of Str. uberis mastitis in dairy cattle.

HLA-DR2, -DR5, and DRw6 associated Dw subtypes correlate with HLA-DR beta and -DQ beta restriction fragment length polymorphisms

Abstract: DNAs extracted from peripheral blood leukocytes of 24 individuals, selected for their HLA-DR types, -DR2, -DR5, and -DRw6, were analyzed with four restriction enzymes, BamHI, EcoRV, HindIII, and Taq I, using the Southern technique. This panel includes 16 individuals with homozygous typing cells and 8 heterozygous individuals who carry rare Dw subtypes or unusual DR-DQ associations. Eighty-five polymorphic fragments were detected and assigned to the DR or DQ gene families according to their hybridization signals. Thirty-eight fragments (DR or DQ) were found to correlate with single DR or Dw specificities or rare associations such as DRw14-DQw3. Forty-two fragments correlated with the association of immunologically defined specificities. In total, these 85 fragments constituted 44 different patterns, each comprising 1-9 fragments. For each homozygous typing cell a combination of patterns was observed. Fourteen different combinations of 10-20 patterns were found among the 16 individuals with homozygous typing cells, showing that Dw18, Dw19, Dw9, and Dw5 are heterogeneous at the genomic level whereas only the Dw2 individuals tested here are identical.

Molecular typing of methicillin and gentamicin resistant Staphylococcus aureus in Dublin.

Abstract: The high incidence of infection in Dublin hospitals caused by non-typable strains of methicillin- and gentamicin-resistant Staphylococcus aureus (MGRSA) has created an important epidemiological problem as conventional methods of sub-dividing these organisms have not been useful. This report describes a novel approach to the typing and analysis of MGRSA strains, particularly non-typable isolates, by comparing restriction endonuclease HindIII digest patterns of total cellular DNA; and by using Southern hybridization analysis to detect size variations or polymorphisms in restriction endonuclease cleavage fragments within small regions of the chromosome. Non-typable MGRSA strains and isolates belonging to two phenotypically related groups of phage-type 77 and 77/84 strains were readily subdivided on the basis of molecular size differences in high molecular weight DNA fragments generated by the enzyme HindIII. Restriction endonuclease fragment size polymorphisms were readily detected in many of the non-typable strains tested in hybridization experiments, and these were used for strain sub-division. Both techniques were useful tools for the separation of closely related MGRSA strains.

Improved, computer-generated system for pyocin typing of Pseudomonas aeruginosa.

Abstract: We applied numerical clustering algorithms to the selection of a new indicator strain set for the pyocin typing of Pseudomonas aeruginosa The new indicator set is composed of selected indicator strains from the sets described in 1966 by Gillies and Govan (J Pathol Bacteriol 91:339-345) and in 1974 by Jones, Zakanycz, Thomas, and Farmer (Appl Microbiol 27:400-406) and is designated the G-F set This indicator set consists of 14 indicator strains which typed 995% of 114 test cultures, has a high degree of discrimination (10 patterns encompass 50% of the test strains), and provides 623% reproducibility of the same typing pattern in duplicate tests done on different days The G-F set of indicator strains provides slightly higher percentages of typable cultures than either of the other two sets, has greater discriminatory capability, and is more reproducible than they are We recommend that the G-F set of indicator strains be used instead of the two other sets for pyocin typing of P aeruginosa We also tested a recently described overlay procedure for pyocin testing of P aeruginosa and found it to be superior to previous methods in that it is easier to perform, it provides answers in only 24 h instead of 48 h, and it can be used to type mucoid strains (which previous techniques could not readily do) Thus, the application of numerical clustering algorithms and use of a revised typing procedure have produced an improved system for pyocin typing of P aeruginosa Similar procedures may be applicable to other typing systems

Assessment of multi-organ system engraftment by genotypic typing using restriction fragment-length polymorphisms and by phenotypic typing using a microcytotoxicity assay.

Abstract: We report the first application of Southern blotting techniques for the quantitative assessment of the donor or host origin of cell populations present in recipients of allogeneic or sex-mismatched syngeneic murine donor marrow grafts. The sensitivity of this assay system was noted to 1 to 5% for detection of a minor cell population by using cDNA probes that hybridize to single-copy sequences in the murine genome. The use of probes that generate distinguishing autoradiographic patterns due to strain-specific genomic sequence variations obviates the need for retroviral vector transfections (which potentially skew engraftment quantitation). Southern blotting analysis has provided definitive engraftment data in multiple cell populations isolated from both short-term and long-term allogeneic and syngeneic radiation chimeras. In contrast, H-2 typing in a microcytotoxicity assay, a standard typing technique for allogeneic murine donor cell engraftment, was noted to be less sensitive than Southern blotting. This occurred particularly in selected cell populations, in ill-appearing recipients, and in the early post-BMT period. Furthermore, because H-2 typing is a phenotypic assay, the results may be substantially influenced by the passive cell surface acquisition of host H-2 antigens, a process that is not evident with the use of genotyping techniques. Our results establish the superiority of Southern blotting techniques for the quantitation of donor cell engraftment and demonstrate the potential of this methodology when low-level detection of engrafted donor or residual host cells is of critical physiologic importance.

Serological and pyocin typing and antibiotic sensitivity of Pseudomonas aeruginosa strains.

Abstract: 94 strains of Pseudomonas aeruginosa, isolated from hospitalized patients, were typed with serological and pyocinic methods, also testing their sensitivity to 6 antibiotics. The serological method allowed for the typing of almost all the strains (98.9%), (the 0-11 serotype was the most frequent -23.4%-) vs. 80.6% by the pyocinic method. Among those tested, ceftazidime was the most active antibiotic, against the P. aeruginosa strains examined.

Plasmid profiling of epidemic staphylococci from around 1960: a comparison of epidemiological techniques.

Abstract: Plasmid profiles have been established for 68 isolates of Staphylococcus aureus from 13 episodes of epidemic spread in hospital wards between 1958 and 1962. Despite the original lack of care in preservation of strains the profiles give, in general, the same epidemiological patterns as were established originally on the basis of phage type, antibiotic sensitivity, ward and date of isolation.

Coagulase typing of Staphylococcus aureus isolated from animals

Abstract: Coagulase typing was performed on Staphylococcus aureus isolated from various animals. Of the 383 strains examined, 209 (54.6%) strains were typable and could be differentiated into 8 coagulase types. The remaining 174 strains were non-typable with antisera against the 8 known types of coagulases. This suggests that many strains of S. aureus of animal origin may possess unknown types of coagulases.

Comparison of cytopathic effect and an enzyme-linked immunosorbent assay using monoclonal antibodies for typing herpes simplex viras isolates

Abstract: 2. Nicolas, J. C., Cohen, J., Fortier, B., Lourenco, M. H., Bricout, F.: Isolation of human pararotavirus. Virology 1983, 124:181 184. 3. Dimitrov, D.H., Estes, M. K., Rangelova, S. M., Shindarov, L.M., Melnick, J. L., Graham, D.Y.: Detection of antigenically distinct rotaviruses from infants. Infection and Immunity 1983,41: 523-526. 4. Tao, H., Changan, W., Zhaowing, F., Zinyi, C., Xuejian, C., Xiaoquang, L., Gungmu, C., Henli, Y., Tungxin, C., Weiwe, Y., Shuasen, D., Weieheng, C.: Waterborne outbreak of rotavirus diarrhoea in adults in China caused by a novel rotavirus. Lancet 1984, ii: 1139-1142. 5. Espejo, R. T., Puerto, F., Soler, C., Gonzales, N.: Characterisation of a human pararotavirus. Infection and Immunity 1984, 44: 112-116. 6. Bridger, J.C.: Detection by electron microscopy of caliciviruses, astroviruses and rotavirus-like particles in the feces of piglets with diarrhoea. Veterinary Record 1980, 107: 532-533. 7. Saif, L. J., Bohl, E. H., Theft, K. W., Cross, R. F., House, J.A.: Rotavirus-like, calicivirus-like, and 23-nm viruslike particles associated with diarrhoea in young pigs. Journal of Clinical Microbiology 1980, 12:105-111. 8. Bohl, E. H., Saif, L. J., Theft, K. W., Agnes, A. G., Cross, R.F.: Porcine pararotavirus: detection, differentiation from rotavirus, and pathogenesis in gnotobiotic pigs. Journal of Clinical Microbiology 1982, 15: 312-319. 9. McNulty, M. S., Allan, G. M., Todd, D., MeFerran, 5. B., McCracken, R.M.: Isolation from chickens of a rotavirus lacking the rotavirus group antigen. Journal of General Virology 1981, 55: 405-413. 10. Chasey, D., Davies, P.: Atypical rotaviruses in pigs and cattle. Veterinary Record 1984, 115:16 17. 11. Snodgrass, D. R., Herring, A. J., Campbell, I., Inglis, J. M., Hargreaves, F. D.: Comparison of atypical rotaviruses from calves, piglets, lambs and man. Journal of General Virology 1984, 65: 909-914. 12. Herring, A. J., lnglis, N. F., Ojeh, C. K., Snodgrass, D. R., Menzies, J. D.: Rapid diagnosis of rotavirus infection by direct detection of viral nucleic acid in silver-stained polyacrylamide gels. Journal of Clinical Microbiology 1982, 16: 473-477. 13. Bridget, 5. C., Brown, J. F.: Prevalence of antibody to typical and atypical rotaviruses in pigs. Veterinary Record 1985, 116: 50. 14. Chasey, D., Banks, J.: The commonest rotaviruses from neonatal lamb diarrhoea in England and Wales have atypical electropherotype. Veterinary Record 1984, 115: 326-327. Comparison of Cytopathic Effect and an Enzyme-Linked Immunosorbent Assay Using Monoclonal Antibodies for Typing Herpes Simplex Virus Isolates

Typing of Staphylococcus aureus resistant to methicillin.

Abstract: resistance quite apart from obesity.367 (3) Without specifically exaning the responses in those who are glucose intolerant it is difficult to draw conclusions regarding pathophysiology, as not all first degree relatives are equally at risk.2 (4) It is extremely difficult to interpret insulin values during oral glucose tolerance tests, and it is even possible that an initially impaired response during the first half hour may induce hyperglycaemaia and subsequent hyperinsulinaemia-a pattern which has been shown since the first immunoassay.8 Because ofthe poor repeatability ofthe oral glucose tolerance test, and the difficulty of interpreting the insulin responses, we prefer to study the response to a continuous infusion of glucose for epidemiological and pathophysiological studies.9

Prevalence of protease and elastase production by clinical isolates of Pseudomonas aeruginosa in relation to aeruginocine typing patterns.

Abstract: Sixty six consecutive P. aeruginosa isolates from heterogeneous clinical specimens were subjected to aeruginocine (pyocine) typing and assayed for in vitro protease and elastase production by a simple and reproducible qualitative test.