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W H Traub

Publications and source records attributed to W H Traub.

At least 19 recordsLinked to original sources

Neutralization of human serum beta-lysin by sodium polyanetholsulfonate and sodium amylosulfate.

Normal fresh and heat-inactivated (56 degrees C, 30 min) human sera (80 vol%, i.e., 80% [vol/vol] of a 2-ml assay volume) killed Bacillus subtilis ATCC 6633 cell inocula of 1.5 x 10(4) colony-forming units per ml within 1 to 2 h after exposure. The B. subtilis assay strain proved slightly and reversibly susceptible to 5 mug of egg white lysozyme per ml. Seitz filtration of fresh human serum completely removed beta-lysin activity; significant amounts of serum lysozyme were removed as well, as determined with the bioassay strain Micrococcus lysodeikticus ATCC 4698. However, bactericidal activity of human serum via classical or alternative complement pathway activation remained intact. Addition of 0.01 M dithiothreitol to fresh human serum abolished beta-lysin activity, but not that of serum lysozyme. Chelation of fresh and heat-inactivated human serum with 0.01 M MgCl(2) + 0.01 M ethylene glycol tetraacetic acid, but not with 0.01 M ethylenediaminetetraacetic acid, markedly retarded beta-lysin activity; however, lysozyme activity remained unaffected. Chelation of serum with 0.01 M MgCl(2) + 0.01 M ethylene glycol tetraacetic acid + 0.01 M CaCl(2) completely abrogated beta-lysin activity, but not that of lysozyme. Absorption of human serum with 10 mg of bentonite per ml (10 min, 37 degrees C) completely removed beta-lysin and lysozyme activity, but failed to affect serum bactericidal activity against Escherichia coli control strain C. Reconstitution of 50 vol% of bentonite-absorbed serum with 40 vol% of heat-inactivated human serum restored both beta-lysin and lysozyme activity. Addition of either 63 to 500 mug of sodium polyanetholsulfonate per ml or 63 to 500 mug of sodium amylosulfate per ml to 80 vol% of fresh human serum completely neutralized beta-lysin activity for the entire observation period of 22 h.

Amylopectin

Variable neutralization of several nonspecific antibacterial systems in fresh, defibrinated human blood by sodium polyanetholsulfonate and sodium amylosulfate.

Fresh, defibrinated human blood (80 vol%, i.e., 80% [vol/vol] of a 2-ml final assay volume) from two healthy adult donors killed "delayed serum-sensitive" (DSS) and "promptly serum-sensitive" (PSS) strains of Serratia marcescens, PSS control strain Escherichia coli C, Bacillus subtilis strain ATCC 6633, and Micrococcus lysodeikticus ATCC 4698 in a kinetic manner comparable to that of fresh human serum (80 vol%). However, heat-inactivated (56 degrees C, 30 min), defibrinated human blood revealed markedly reduced or a total lack of beta-lysin activity against the B. subtilis assay strain. Similarly, lysozyme activity of defibrinated blood was diminished somewhat by heat treatment, as determined with the M. lysodeikticus assay strain. Addition of 500 mug of sodium polyanetholsulfonate (SPS) per ml to 80 vol% of fresh, defibrinated human blood completely neutralized blood bactericidal activity against all assay strains of S. marcescens, E. coli C, and B. subtilis; however, SPS at this concentration failed to abolish lysozyme activity for prolonged periods of incubation. Addition of 500 mug of sodium amylosulfate (SAS) per ml to 80 vol% of fresh defibtinated human blood resulted in protection of cell inocula of DSS strains of S. marcescens only; SAS failed to protect cell inocula of the PSS strains of S. marcescens, E. coli C, B. subtilis, and M. lysodeikticus for extended periods of observation. Based on these data, it is recommended that blood culture specimens that are first drawn into specimen containers (such as Vacutainer tubes or the like) at the patient's bedside, and which contain >/=250 mug of SPS per ml, be diluted into suitable broth media with at least >/=250 mug of SPS per ml by the receiving laboratory within 2 to 4 h after procurement of the specimen. This procedure would ensure continued, adequate neutralization of the specimen's inherent beta-lysin, lysozyme, and complement- and antibody-mediated bactericidal activities.

Amylopectin

Serotyping of Serratia marcescens: current status of seven recently described flagellar (H) antigens.

The slightly revised, current scheme of 20 flagellar (H) antigens of Serratia marcesens was examined. The seven new H antigens were demonstrated to be antigenically distinct as determined with Le Minor's H-immobilization test. The H-immobilization antibodies of rabbit anti-H immune sera proved resistant to treatment with 2-mercaptoethanol and dithiothreitol, respectively. On the other hand, dual absorptions of rabbit anti-H immune sera with killed cells of Staphylococcus aureus strain Cowan I, i.e., protein A, failed to reduce significantly H-immobilization titers of rabbit sera, although human immunoglobulins G and M were bound by protein A. It was tentatively concluded that the 2-mercaptoethanol- and dithiothreitol-refractory H-immobilizing rabbit antibodies belonged to the immunoglublin M class. H-antigen (phase) variation was not demonstrable in several extramural, clinical isolates of S. marcescens for which this phenomenon had been claimed. Rather, four of these six isolates were found to consist of cell populations of two distinct serotypes, as also borne out by bacteriocin typing; the flagellar H-antigens of the remaining two isolates were stable, with minor, hterologous H-antigen cross-reactivity.

Antigens, Bacterial

In vitro additive effect of nitrofurantoin combined with trimethoprim-sulfamethoxazole against Serratia marcescens.

The combination of nitrofurantoin (NF) plus trimethoprim-sulfamethoxazole (TMP-SMZ) was found to be additively effective against all of 12 clinical isolates of Serratia marcescens that represented 7 nosocomially significant strains, some of which were mulitple-drug-resistant. All isolates were resistant against NF; minimal inhibitory concentrations (MICs) ranged from 320 to 1,280 microgram NF/ml. The isolates were inhibited by TMP-SMZ concentrations ranging from 0.03 microgram TMP + 0.57 microgram SMZ/ml to 8 microgram TMP + 152 microgram SMZ/ml. Significantly, NF combined with TMP-SMZ proved effective against isolates with decreased susceptibility to TMP-SMZ as well. The observed in vitro additive effect of NF + TMP-SMZ might prove of clinical relevance with respect to the chemotherapy of hospital-acquired urinary tract infections due to multiple-drug-resistant strains of S. marcescens.

Drug Combinations

Nonspecific resistance of Serratia marcescens against antimicrobial drugs. Resistance or decreased susceptibility of phenotypic variants against chloramphenicol, nalidixic acid, nitrofurantoin, sulfonamides and trimethoprim.

Several clinical isolates and O-antigen reference strains of Serratia marcescens were shown to yield spontaneously phenotypic variants with nonspecific, combined resistance or decreased susceptibility for chloramphenicol, nalidixic acid, nitrofurantoin, sulfonamides, and trimethoprim, including cotrimoxazole. Additional presumptive evidence indicated that this resistance phenomenon is not mediated extrachromosomally, but rather chromosomally. The nature of this novel resistance mechanism remains to be elucidated.

Chloramphenicol

Nonspecific aminoglycoside cross-resistance of Serratia marcescens.

10 of 11 clinical isolates of Serratia marcescens yielded small numbers (10(-7) to 10(-8)) of 'gray' colony-type variants after selection with either amikacin, gentamicin or kanamycin, of which most proved resistant against all of the following aminoglycoside antibiotics: amikacin, gentamicin, kanamycin, neomycin, netilmicin, sisomicin and streptomycin. The level of resistance was not absolute, but rather low-level to intermediate. All except two of these 'gray', resistant phenotypic variants yielded 'opaque' revertants which were essentially indistinguishable from the parent (wild type) strains in terms of colonial morphology and antibiotic susceptibility. The 'gray' variants kinetically were more susceptible to the bactericidal activity of fresh human serum than the 'opaque' variants. Preliminary evidence afforded the tentative conclusion that this nonspecific aminoglycoside-resistance mechanism was not plasmid-mediated.

Amikacin

Serotyping of Serratia marcescens: simplified tube O-agglutination test and comparison with other serological procedures.

A simplified tube O-agglutination test was developed and evaluated for the determination of somatic serogroup (O) antigens of Serratia marcescens. Use was made of Tryptic Soy broth (TSB)-grown O-cells that had been boiled for 1 hour; 0.145 M NaCl proved a satisfactory diluent. Various technical parameters of this test were examined as well. Rabbit anti-O immune sera, that had been elicited with 5 x concentrated, TSB-grown, 1 hour-boiled O-cells of all 15 currently employed O-antigen reference strains of S. marcescens yielded satisfactory O-agglutinin titers. The tube O-agglutination test compared favorably with the indirect hemagglutination technic, although the latter technic yielded significantly higher O-agglutinin titers with merely 7 of the 15 O-antigens of S. marcescens. The tube O-agglutination test permitted detection of higher O-agglutinin titers than a microtiter O-agglutination test utilizing O-cells that had been stained with safranin O. Conversely, titers obtained with TTC-stained O-cells in a microtiter agglutination procedure approximated those yielded by the tube O-agglutination test, but O-cells of the various S. marcescens strains were stained nonuniformly by triphenyltetrazolium chloride (TTC). As before, there existed marked serologic cross-reactivity between O-antigens O6 and O14. A new O6 candidate strain, S. marcescens isolate S 1i, serotype O6:H20, was proposed. Contrary to O-agglutinins of human control serum, the O-agglutinins of rabbit anti-O immune sera proved refractory to treatment with 0.1 M of 2-mercaptoethanol (2-ME) and 0.01 M dithiothreitol (DTT) respectively. Dual absorptions of rabbit anti-O immune sera with killed cells of Staphylococcus aureus Cowan I (protein A), failed to significantly reduce O-agglutinin titers, although human IgG and IgM was bound by protein A. It was tentatively concluded that the 2-ME- and DTT-refractory rabbit anti-S. marcescens O-agglutinins resided in the IgM immunoglobulin class.

Agglutination Tests

Mammalian serum susceptibility of Serratia marcescens: detection of three human serum susceptibility categories.

A total of 65 strains of S. marcescens, including 36 currently employed O- and H-antigen reference strains, were examined for their susceptibility to the bactericidal activity of 80 vol % of fresh human serum. The majority of strains (57 = 87.6%) proved 'delayed serum-sensitive' (DSS); 4 strains (6.2%) were 'promptly serum-sensitive' (PSS), whereas 4 strains (6.2%) resisted (NSS) complement-mediated killing by human serum. Fresh sera obtained from 7 adult human volunteers yielded essentially identical kinetic killing data against representative NSS, DSS and PSS strains of S. marcescens. These observations were interpreted as further justification for the assignment of clinical isolates of S. marcescens to 3 categories of human serum susceptibility: DSS, PSS and NSS. Species differences among fresh sera from sheep, rabbits and guinea pigs, as contrasted with fresh human serum, were noted. In general, PSS strains of S. marcescens were killed in a slightly delayed fashion; DSS strains of S. marcescens were killed in an unpredictable kinetic pattern by sheep and rabbit sera, whereas fresh guinea pig serum entirely failed to kill selected DSS isolates of S. marcescens.

Adult

Further characterization of "promptly" and "delayed" human serum-sensitive strains of Serratia marcescens.

The kinetics of the bactericidal activity of 80 vol% of fresh human serum against representative 'delayed serum-sensitive' (DSS) and 'promptly serum-sensitive' (PSS) strains of Serratia marcescens were further examined with regard to various chemical and absorption procedures known to affect various components of the alternative and classical pathways of human complement activation. Inulin treatment of fresh human serum failed to diminish serum bactericidal activity against DSS and PSS assay strains. Fresh human serum that had been depleted of properdin (factor P) through absorption with zymosan, was as active as control serum against DSS strains of S. marcescens; however, PSS strains were killed in a 'delayed' fashion. Human serum that had been heat-inactivated at 50 degrees C for minutes (depletion of factor B), no longer killed DSS strains, whereas PSS strains of S. marcescens and the PSS control strain Escherichia coli C were killed in a slightly delayed fashion. Hydrazine-hydrate treatment (inactivation of C3 of the complement system) and exposure of fresh human serum to dithiothreitol completely abolished serum bactericidal activity. Bentonite-absorbed fresh human serum no longer killed DSS strains of S. marcescens; some PSS strains of S. marcescens were killed in a delayed manner, whereas control strain E. coli C was as PSS as before. Addition of Seitz-filtered fresh human serum, that lacked beta-lysin and was deficient in lysozyme, to bentonite-absorbed human serum restored bactericidal activity against DSS and PSS strains of S. marcescens; addition to heat-inactivated or Seitz-filtered, heat-inactivated human serum failed to do so. Therefore, bentonite absorption removed to a heat-labile component from fresh human serum clearly different from beta-lysin and lysozyme. Furthermore, human serum beta-lysin and lysozyme were not required for serum-mediated killing of S. marcescens strains of either serum susceptibility category.

Absorption

Neutralization of human serum lysozyme by sodium polyanethol sulfonate but not by sodium amylosulfate.

Sodium polyanethol sulfonate (SPS) at 500 microgram/ml, but not sodium amylosulfate (SAS) at 500 microgram/ml, precipitated egg white lysozyme (1 mg and 50 microgram of lysozyme per ml) as determined with the assay strain Micrococcus lysodeikticus ATCC 4698. Fresh and heat-inactivated (56 degrees C, 30 min) human serum (80%, vol/vol) killed M. lysodeikticus (10(4) bacteria per ml at zero time) within 1 to 2 h after exposure. Addition of 250 to 500 microgram of SPS per ml to fresh human serum protected M. lysodeikticus for 22 h as effectively as absorption of either fresh or heat-inactivated human serum with bentonite (10 mg/ml of serum, 10 min, 37 degrees C); the latter procedure is known to remove serum lysozyme. In contrast, SAS at 250 and 500 microgram/ml of serum retarded killing of the assay bacteria for periods of 4 h; after overnight (22 h) incubation, however, the number of M. lysodeikticus survivors had decreased significantly. The finding that SPS, but not SAS, at 250 to 500 microgram/ml effectively neutralized serum lysozyme-mediated killing of a lysozyme-sensitive assay strain may be of relevance with respect to laboratory processing of human blood culture specimens.

Absorption

Serotyping of Serratia marcescens: evaluation of Le Minor's H-immobilization test and description of three new flagellar H antigens.

The H-immobilization test of Le Minor for determining flagellar (H) antigens was evaluated and compared with tube and slide H-agglutination tests. The test proved specific and easy to perform, and titration end points were clearly discernible. The degree of serological cross-reactivity between H antigen reference strains of Serratia marcescens was low. Consequently, this test was adopted for routine serological analysis of H antigens, using unabsorbed rabbit immune anti-H sera. As a result of using this procedure, three new provisional H antignes, designated H14, H15, and H16, are proposed.

Antigens, Bacterial

Inactivation of classical and alternative pathway-activated bactericidal activity of human serum by sodium polyanetholsulfonate.

Sodium polyanetholsulfonate (SPS) at a final concentration of at least 250 microng/ml (0.025%) was required for inhibition of the bactericidal activity of 80% (vol/vol) of fresh human serum against "promptly serum-sensitive" strains of Serratia marcescens and control strain Escherichia coli C, i.e., for inhibition of the classical pathway of complement activation. In contrast, SPS at 125 microng/ml (0.0125%) was sufficient for neutralization of the bactericidal activity of 80% (vol/vol) fresh human serum against "delayed serum-sensitive" strains of S. marcescens known to activate the alternative pathway of human complement. Addition of up to 500 microng of SPS per ml to 80% (vol/vol) fresh human serum failed to neutralize transferrin-mediated, "late" bacteriostasis against control strain E. coli C, an effect that was demonstrable only after prolonged, i.e., overnight, incubation of the test strain. However, this late inhibitory effect against E. coli C was not observed in SPS-treated 20% (vol/vol) fresh human serum or in 10 or 20% (vol/vol) conventionally heat-inactivated human serum. Immunoelectrophoretic examination disclosed that SPS did not precipitate transferrin from either fresh or heat-inactivated human serum. Thus, SPS, at 250 microng/ml, was demonstrated to be sufficient for the inhibition of both classical and alternative complement pathway-activated bactericidal activity of 80% (vol/vol) human serum. However, SPS at a concentration of 500 microng/ml failed to antagonize one antimicrobial system of 80% (vol/vol) human serum, namely transferrin-mediated bacteriostasis.

Benzenesulfonates

Studies on neutralization of human serum bactericidal activity by sodium amylosulfate.

The synthetic anticoagulant sodium amylosulfate (SAS) at concentrations of 125 to 2,000 microgram/ml failed to completely neutralize the bactericidal activity of 80 and 50% (by volume) fresh human serum. Furthermore, SAS failed to inhibit the alternative pathway of complement activation in 80% (by volume) fresh human serum that had been chelated with 0.01 M magnesium ions plus 0.01 M ethyleneglycol-bis(beta-aminoethylether)-N,N-tetraacetic acid. However, SAS at 250 to 1,000 microgram/ml effectively neutralized the bactericidal activity of 20% (by volume) fresh human serum. Therefore, SAS (at 250 to 1,000 microgram/ml) should be used only in blood samples that have been diluted at least fivefold (less than or equal to 20% [by volume]) in suitable broth media.

Amylopectin