Showing papers on "Typing published in 1977"

Typing of Proteus strains by proticine production and sensitivity.

Abstract: SUMMARY A simple, reliable and highly discriminating scheme for the bacteriocine typing of Proteus has been developed. Strains are typed on MacConkey's agar according to their ability to produce a proticine active against one of 14 indicator strains having a single and specific proticine sensitivity and also according to their sensitivity to the different proticines of 13 proticine-producing strains. This new scheme of combined production and sensitivity typing was formulated after 250 strains of Proteus from clinical material had been examined for the production of proticines active against the 24 indicator strains of Cradock-Watson's proticine typing scheme and for proticine activity and sensitivity towards each other. Three new types of proticinogenic strains were discovered and defined. Strains producing proticines of types 1, 2 and 3 were isolated frequently. These common proticines could be subtyped by their different actions on newly characterised indicator strains. By means of this production/sensitivity (P/S) typing scheme, 250 Proteus strains were differentiated into 90 distinct types, whereas typing by sensitivity alone distinguished only 40 types and typing by production alone distinguished only 20 types (including subtypes).

Establishment of a new bacteriophage set for typing avian staphylococci.

Abstract: A new phage set was proposed for the typing of coagulase-positive staphylococci from chickens. The set was composed of 16 phages isolated from lysogenic staphylococci from chickens and 3 adapted phages derived from the international phage set. These phages were classified into 4 groups (I, II, III and IV) according to their host ranges. The 19 phages were used for typing 569 coagulase-positive staphylococci; 94.2% of the isolates were lysed by 1 or more phages, 88.0% at a routine test dilution, and 6.25% only at a routine test dilution X 100. The reacting ability of the phages seemed to be limited to staphylococci from chickens. It was proved that the phages were more accurate than the international phage set in typing staphylococci isolated from chicken in Japan.

A comparison of typing methods for Serratia marcescens

Abstract: SUMMARY A simple method for the bacteriocine typing of Serratia marcescens without the use of induction was sought. The results of a mutual inhibition e2rperiment with 89 unrelated cultures indicated that a bacteriocine-susceptibility method would give more discrimination between strains than would a bacteriocine-production method. A cross-streaking technique for bacteriocine-susceptibility typing without previous induction was developed, and its performance was compared with that of another susceptibility-typing method in which cell-free lysates of the producer strains were obtained by induction with mitomycin C. Replicate typing of the same collection of cultures by both methods indicated that small variations in pattern were common and that larger variations occurred occasionally. Differences in pattern of less than two strong reactions in the mitomycin-C induction method, and of less than three strong reactions in the crossstreaking method, should therefore not be taken as evidence that strains can be distinguished. Sets of cultures of Ser. marcescens, 178 in total, from a number of supposed incidents of infection in hospitals, were used to evaluate the two bacteriocinetyping methods; all of the cultures were also O serogrouped. Comparison of the typing patterns of members of the same O serogroup from clear-cut incidents of infection confirmed that results of acceptable reliability could be obtained by either bacteriocine-typing method by the application of the appropriate 'difference ' rule. When so interpreted, the cross-streaking method appeared to be slightly the more discriminatory. The greatest discrimination between strains was obtained by the use of a ' hierarchical ' typing system in which the strains were first O serogrouped, and the cross-streaking method of bacteriocine typing was then used to make subdivisions within O serogroups.

Broad antigenicity exhibited by some isolates of avian adenovirus.

Abstract: Ten of 16 isolates of avian adenovirus could be readily classified as members of serotypes 2, 5, or 7. However, 6 exhibited broad neutralization reactions which created typing problems. Detailed studies of these interactions revealed that our prototype for serotype 5 (i.e., T-8; subsequently found to be an "intermediate" strain) contributed to this broad cross-reactivity because it shared antigens with members of serotypes 5 and 7. As a result of this study, TR-59 or 58-1 is recommended as the suitable prototype for the serotype 5 viruses. The 6 broadly reactive isolates were classified as serologic "variants" of serotypes 5 and 7.

Bacteriophage typing of Corynebacterium diphtheriae.

Abstract: Bacteriophage types of over 3,000 strains of Corynebacterium diphtheriae isolated in Canada have been determined. The typing scheme used involved the use of nine phages. Results indicated that phage types correlate with biotypes to a large degree. Corynecin types were also determined for a limited number of cultures, and results indicated that the indicator strains presently available are unsuitable for the typing of C. diphtheriae strains isolated in North America. The distribution of phage types is similar throughout Canada, and the types present correspond to types reported from other countries. Phage typing could be of value in the study of circumscribed outbreaks and in epidemiological surveillance of types over long periods. Phage typing of bacterial cultures has been found to be useful in tracing epidemiological relationships among strains. Among the schemes in use are those for Salmonella typhi, Salmonella typhimurium, Staphylococcus aureus, and Pseudomo

Histocompatibility typing in spontaneous regression of retinoblastoma.

Abstract: Human Leukocyte Antigen (HLA) Typing of Caucasian patients with retinoblastoma fails to show any difference in antigen frequency compared to a control population. In family studies where several members are affected with retinoblastoma the tumor does not segregate with the HLA type. There is also no significant difference in antigen frequency between spontaneous regression of retinoblastoma, unregressed retinoblastoma, and normal controls. In several families with one member showing spontaneous regression of retinoblastoma, other generations inheriting the same haplotypes have tumors which have failed to regress.

Relation Between HLA-DW and the B-Lymphocyte Specificities

Abstract: Homozygous DW typing cells were tested for six B-lymphocyte specificities. All four of the second locus specificities of B lymphocytes were strongly associated with the DW specificities. DW1 typing cells were B group 6, DW2 were B4, DW3 were B5, and LD107 were B3. The first B-cell locus antigens 1 and 2 tended to be uniform within the DW groups. From an analysis of the typing responses of a panel of cells to the homozygous typing cells, it has become apparent that the first B-locus specificity present on the homozygous typing cells also plays a role in determining whether a typing response is obtained or not. Thus, the DW3 typing cells were themselves B2 and B5, and cells having B2-B5 were most frequently nonreactive to DW3 in mixed lymphocyte culture. Homozygous typing cells therefore mainly detect the second B-cell locus antigens and, to a lesser degree, the first locus specificities. Stated another way, homozygous typing cells do not define a single specificity, but rather the presence of two B-lymphocyte specificities, even though their responses often reflect matching of only the second B-locus specificity.

Evaluation of a new bacteriophage set for typing of Staphylococcus epidermidis strains.

Abstract: A new set of typing phages was evaluated for typing 821 Staphylococcus epidermidis strains isolated from normal human skin and from acne lesions. This method was compared with two different systems for biochemical differentiation of S. epidermidis. Distinct subgroups of cocci, which differed in phage susceptibility as well as in biochemical properties, were found. A tentative subdivision of S. epidermidis strains by use of 16 phages arranged into four groups is proposed, together with additional biochemical differentiation of non-typable strains.

Epidemiological Information from Active and Passive Pyocine Typing of Pseudomonas Aeruginosa

Abstract: An investigation was carried out to determine the value of active and passive pyocine typing in the study of Pseudomonas aeruginosa infections acquired in hospital. Active typing was a more reliable and reproducible method than passive typing. Both methods were used in studies of nine outbreaks of infection. In six of these episodes there was good agreement between the two methods. Less clear-cut results were achieved in the remaining three episodes. In one of these, active typing gave more valuable information. However, both methods are easy, convenient and of value in epidemiological studies.

Detection of HLA-D clusters using primed LD typing.

Abstract: Using a set of 17 primed LD typing (PLT) cells tested on a panel of 35 unrelated cells, we showed that certain groups of PLT cells tended to detect similar unrelated cells. The PLT cells were grouped into seven clusters and these tended to correlate with the seven HLA-D specificities represented on the panel, as determined by HTC testing. These data suggest that the antigens that cause restimulation in PLT are similar to those HLA-D antigens detected by the homozygous typing cell (HTC) test or, alternatively but more unlikely, that the two typing methods are detecting genes in close linkage disequilibrium with the HLA-D region.

Pi (antitrypsin) typing methods. A comparison of acid starch-gel electrophoresis and isoelectric focusing.

Abstract: The Pi typing methods acid starch-gel electrophoresis (ASGE) and isoelectric focusing (IEF) have been compared by three reference laboratories: 564 samples of phenotypes Pi M, MS and MZ were tested in each of the three laboratories with a 96% agreement on initial typing. The discrepancies are recorded and reasons for disagreement discussed. IEF is a reliable method for Pi typing and gives results comparable to those obtained by ASGE.

Detection by three cellular immunological techniques of the antigenic determinants of the Ly-Li system, expressed on human B lymphocytes.

Abstract: A clear correlation was observed between the presence of an Ia-like antigenic B-cell system Ly-Li, detected serologically, and three cellular immunological techniques: [1] mixed lymphocyte reaction (MLR) inhibition by an anti-Li antiserum; [2] level of restimulation of anti-Ly-Li in-vitro-primed lymphocytes; and [3] detection of HLA-D alleles by homozygous typing cells. These results suggested that the allelic products detected serologically may be identical to those detected by the first two techniques, namely MLR inhibition and in-vitro-primed lymphocyte typing, and, possibly, HLA-D typing using homozygous typing cells, although the correlation was repeatedly found to be less clear for the last technique.

Bacteriophage typing of chicken staphylococci by adapted phages.

Abstract: Phage typing was performed on 452 strains of Staphylococcus aureus Iso-fated from diseased or apparently healthy chickens and from air samples in poultry houses.By use of 26 phages of the International Series, 260 (57.5%) of 452 strains were typed.On the other hand, four adapted phages (CHAT, CHA2, CHA3 and CHA4) were estabIished from phages 3A, 3C and 75 of the International Series, and their usefulness fortyping of chicken staphylococci was evaluated. As a result, 336 (74.3%) of 452 strains testedwere successfully typed with one or more of the four adapted phages, 284 strains at routinetest dilution (RTD) and 336 strains at 100 RTD. About 70% of strains untypable by thephages of the International Series were lysed by one or more of the adapted phages. The336 typable strains were differentiated into 13 phage patterns. The phages seemed to behighly specific to chicken staphylococci, because they lysed only a few strains of animalorigin other than chicken strains. Thus, the 4 phages newly established were found to bevery useful for typing of chicken strains.

Response of primed LD typing cells to homozygous typing cells.

Abstract: At least two different methods using cellular responses have been described for defining the determinants of the HLA-D region: typing with HLA-D homozygous cells and primed LD typing. Primed LD typing cells were generated in one-haplotype-different combinations and grouped on the basis of two or more cells appearing to define the same HLA-D-region-determined PL antigen. Such cells were restimulated with homozygous typing cells for several of the presently known HLA DW clusters. A very strong correlation was noted: PLT cells defining the antigen PL1 were restimulated with homozygous typing cells for DW3, those PLT cells defining the antigen PL2 were restimulated by homozygous typing cells for DW2, and those defining PL5 were restimulated by homozygous typing cells for DW1.

Streptococcus group B typing: comparison of counter-immunoelectrophoresis with the precipitin method.

Abstract: The method of counter-immunoelectrophoresis (CIE) was tested for its applicability to group B streptococcus typing. The results obtained were compared with the typing by the ring precipitin test. Identical antigens and identical hyperimmune typing serum batches had been used in both methods. A large majority of 75 freshly isolated strains were typed identically by both methods. Five strains with a weak antigenic outfit were untypable by the ring precipitin test but were typed by CIE owing to a higher sensitivity of CIE method. Two strains were typable by the precipitin test but not by CIE; an explanation for this phenomenon is lacking. The CIE method in group B typing is specific, rapid, highly sensitive and relatively simple. It requires strict maintenance of standard conditions. The method is economical with respect to manipulation and material, requires small amounts of diagnostic antisera. Potent antisera may be used diluted. Moreover, sera for CIE typing need not be absorbed to remove group B antibodies. CIE method is practicable for group B streptococcus typing, especially in laboratories carrying out routine large scale type identification.

Type specificity and use of human sera for rapid typing of herpes simplex virus isolates by an indirect peroxidase-labeled antibody technique: a comparison with three other methods.

Abstract: Human sera from patients showing seroconversion following a primary herpes simplex virus type 1 (HSV-1) or HSV type 2 (HSV-2) infection, as well as 19S and 7S fractions obtained from the same sera, have been used for typing 191 HSV isolates by an indirect peroxidase-labeled antibody (PLA) method. Typing has also been performed on all of the isolates using a microneutralization (MN) and the indirect hemagglutination (IHA) inhibition test. Furthermore, 30 isolates have been typed by a plaque method. Results obtained with the PLA method was in complete agreement with those of the other two procedures. The PLA method is rapid and simple, offers easy interpretation and a permanent record of results.

Joint report of the first workshop of the LD typing study group.

Abstract: In the first workshop of the American LD Typing Study Group, six exchanged typing cells were used by all participants. Several other homozygous typing cells were included in individual experiments by the participating laboratories. The data obtained from LD typing of 142 individuals, among whom were members of 33 families, were submitted for joint analysis by computer. Several typing cells appeared to recognize new HLA-D specificities. Their typing reactions were clearly discernible in the computer analysis of the results using the 25th percentile stabilization method. The next phase of this work will consist of an expanded study of the families included in the present report.

Hl-a as a diagnostic aid in incomplete rheumatic syndromes

Abstract: Incomplete Reiter's syndrome (ICRS) and incomplete Behcet's disease (ICBD) have many similar clinical features, making the diagnosis difficult. The association of RS and BD with different HL-A antigens is a help in differentiating between the two diseases. Eight patients with incomplete rheumatic syndrome are described. The results of HL-A typing suggest that five patients had incomplete RS and the other three incomplete BD. The value of tissue typing in the correct diagnosis of incomplete rheumatic syndrome is stressed.

Immunogenetic Studies of Rhesus Monkeys IX. The M and N Blood Group Systems

Abstract: Five alloimmune rhesus monkey blood typing reagents have been produced which define two new blood group loci in Macaca mulatta. Three of these reagents detect blood group factors at the M locus; the other two detect factors at the N locus. By typing over 1900 pedigreed monkeys we have established that these two loci are independent of each other and of any of our previously defined blood group systems.

New Staphylococcus aureus phage type 94/96(292) associated with a fatal septicemia.

Abstract: A fulminating septicemia due to Staphylococcus aureus phage type 94/96(292) resulting in the death of a patient with no previous history of illness. This newly characterized strain is identified by an additional typing reaction with experimental phage 292. The prevalence of this strain is discussed.

Etiologic role of bacteria of the genus Providencia in acute intestinal diseases

Abstract: A study was made of morphological, cultural, biochemical properties and antigenic structure (by O-antigen) of 59 strains isolated in group acute intestinal affection of children at the pioneer camp. By the combination of biochemical properties (31 tests) all the cultures isolated were referred to Providencia alcalifaciens of biotype 7. Serological typing with the aid of experimental diagnostic agglutinating O-sera showed these strains to be referred to serological group O2. Identity of the O-antigen of the isolated cultures to the standard O2 strain was confirmed by the results of cross reactions of agglutinin absorption. The results of bacteriological and clinico-epidemiological studies offered a possibility of regarding the isolated Providencia alcalifaciens of serological group O2 as the causative agents of the group intestinal disease in children.