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J L Penner

Publications and source records attributed to J L Penner.

At least 55 records · Page 3Linked to original sources
PubMed1988

MR/K hemagglutination of Providencia stuartii correlates with adherence to catheters and with persistence in catheter-associated bacteriuria.

Providencia stuartii was the most prevalent bacterial species isolated, for one year, from weekly urine specimens from 51 long-term catheterized patients. Significantly more strains causing bacteriuric episodes of long duration expressed MR/K (mannose-resistant/Klebsiella-like) hemagglutination (74%) than did those causing episodes of short duration (26%; P = .004). Isolates expressing MR/K hemagglutinin bound in higher numbers to catheter material (P = .023) than did those not expressing this hemagglutinin. Significantly more strains causing bacteriuric episodes of short duration expressed the mannose-sensitive (MS) hemagglutinin (43%) than did those causing episodes of long duration (7%; P = .014). Isolates expressing MS hemagglutinin bound significantly more 125I-labeled Tamm-Horsfall protein (THP) than did isolates not expressing this hemagglutinin (P = .0001). Our results indicate that MR/K hemagglutinin plays an important role in the ability of P. stuartii to persist and suggest that MR/K adheres to the catheter. Conversely, MS hemagglutinin binds to THP and may prevent persistence of P. stuartii in the catheterized urinary tract.

Aged↗
PubMed1988

The genus Campylobacter: a decade of progress.

In 1977, microbiologists and clinicians were awakened to the importance of the genus Campylobacter when it was learned that one species, Campylobacter jejuni, was a major cause of human enteritis. In the following decade substantial advances were made in diagnosis, isolation technology, identification, classification, serotyping, and epidemiology. The genus has undergone rapid expansion as advantage was taken of the deoxyribonucleic acid-deoxyribonucleic acid hybridization technique in defining new species. The 14 species now included in the genus, however, constitute a widely diverse group, and one species, C. pylori, which is associated with human gastroduodenitis, is under consideration for reassignment to another genus. The nomenclature of the subspecies of C. fetus has been resolved and the role of C. fetus subsp. fetus as an agent of human infections has been more clearly defined. The thermophilic campylobacteria that are etiological agents of human enteritis now include three species, C. jejuni, C. coli, and C. laridis. Recently defined species that have also been implicated as enteritis-causing agents include C. hyointestinalis, "C. upsaliensis," "C. cinaedi," and "C. fennelliae." The aerotolerant campylobacteria are now included in the species C. cryaerophila, and the campylobacteria isolated from salt marshes are included in C. nitrofigilis. The taxonomy and nomenclature of C. sputorum have been revised. C. sputorum now consists of three biovars (biotypes). Two of these, biovar sputorum and biovar bubulus, were previously considered to be separate subspecies and the third, biovar fecalis, was previously regarded as a separate species and known as "C. fecalis." The former subspecies C. sputorum subsp. mucosalis has been elevated to the rank of species. C. mucosalis is metabolically closely related to C. consisus. Human pathogens have not been identified among C. sputorum, C. mucosalis, or C. concisus. The goal of this article is to review developments during the last 10 years with emphasis on changes in taxonomy that are important from the perspective of the clinical microbiologist.

Animals↗
PubMed1988

Role of the 92.5-kilodalton outer membrane protein of Campylobacter jejuni in serological reactions.

Outer membrane proteins from 12 strains of Campylobacter jejuni were examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting with rabbit antisera prepared against Formalin-treated cell suspensions of three of the strains. The 92.5-kilodalton protein was confirmed to be a minor outer membrane protein and exhibited serological heterogeneity. Serological specificities of the proteins, however, were found not to correlate with serotypic specificities of the strains, as demonstrated by slide agglutination tests with whole-cell suspensions. The results suggested that the 92.5-kilodalton proteins were not likely to be participating antigenic determinants in the immunological reactions that give rise to agglutination of live-cell suspensions in the slide test.

Agglutination Tests↗
PubMed1988

Identification of an antigen common to different species of the genus Campylobacter.

Affinity-purified antibody specific for a determinant on flagellin from Campylobacter jejuni was used to screen by immunoblotting strains of C. coli, C. laridis, C. fetus, "C. upsaliensis," C. pylori, and C. sputorum biovar fecalis. The antigen was detected in each of these species, but the molecular weights of the proteins bearing the common antigen varied considerably.

Antibodies, Bacterial↗
PubMed1987

Structural and antigenic properties of lipopolysaccharides from serotype reference strains of Campylobacter jejuni.

To investigate the molecular basis for heat-stable antigenic diversity in Campylobacter jejuni, lipopolysaccharides (LPSs) from serotype reference strains and serotyped isolates were examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis coupled with silver staining and immunoblotting. By silver staining, only low-Mr components, consisting of one major band and as many as three minor bands ranging in Mr from 4,500 to 5,000, were detected. However, by immunoblotting with homologous antisera, 10 of 34 strains were shown to have a series of high-Mr LPS components characteristic of molecules with O side chains of various lengths. Isolates of the same serotype as the reference strain that had high-Mr LPS molecules were also found to have high-Mr LPS and in one case of cross-reacting strains it was found that the cross-reaction was associated with antibodies against high-Mr LPS. The reactions of LPSs with homologous and heterologous antisera indicated that both high- and low-Mr-type LPSs were strain-specific antigens, but in some cases cross-reactions were noted. Evidently, all C. jejuni strains possess low-Mr LPS that is readily detectable by silver staining, but some serotypes also possess high-Mr LPS components that can be visualized by immunoblotting.

Antigens, Bacterial↗
PubMed1987

Urease activity of Proteus penneri.

Ten strains of Proteus penneri isolated from geographically diverse laboratories were tested for urease activity. Cell lysates from urea-induced cells had a mean activity of 4.9 +/- 4.1 mumol of NH3 per min per mg of protein. On nondenaturing 6% polyacrylamide activity gels, the enzymes of P. penneri had very similar electrophoretic mobilities within species and within the Proteus genus but were distinct from the ureases of Providencia and Morganella species. On lower-percentage polyacrylamide, differences in mobilities of the ureases could be detected between the Proteus species. From representative strains, the P. penneri urease was found to be inducible by growth in urea and had an apparent molecular weight of 246,000 +/- 9,000, an isoelectric point of 5.1, and a Km for urea of 14 mM and was inhibitable by acetohydroxamic acid, hydroxyurea, and EDTA. In an in vitro model of struvite formation, a P. penneri strain produced abundant crystals on a glass rod submerged in synthetic urine in the absence but not presence of acetohydroxamic acid (500 micrograms/ml).

Chromatography, Gel↗
PubMed1987

Expanded clinical spectrum of infections caused by Proteus penneri.

Strains of Proteus penneri from seven abdominal wounds (after bowel resection), five urine samples, and eight other sites were isolated in mixed cultures. Seven urine isolates were in pure cultures. All infections were nosocomially acquired, indicating that complete identification of P. penneri in the clinical laboratory is warranted.

Aged↗
PubMed1987

Problems in identification of Campylobacter jejuni associated with acquisition of resistance to nalidixic acid.

In a patient with campylobacteriosis, we observed development of resistance to nalidixic acid and norfloxacin under adequate treatment with the latter antibiotic. Isolates before and after treatment differed in their total protein profile but were otherwise identical with respect to enzymatic activity, serotype, crude membrane protein profiles, and other phenotypic characteristics.

Adult↗
PubMed1987

Investigation of a Providencia rettgeri strain that has enterobacterial common antigen in the immunogenic state.

Antigenic material obtained by phenol-water extraction from Providencia rettgeri strains, Escherichia coli O:14 strains, and mutants of the E. coli O:14 strain were examined by the passive (indirect) hemagglutination technique, by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and by immune blotting (lipopolysaccharide (LPS) blotting). Providencia rettgeri 965, like E. coli O:14, was demonstrated to have an enterobacterial common antigen (ECA) in the immunogenic form but, unlike E. coli O:14, it possessed characteristics of a smooth strain. Two populations of molecules were observed to occur in P. rettgeri 965 phenol-water extracts: one consisting of LPS identifiable with specific O antisera and the other of ECA molecules identifiable with E. coli O:14 antiserum or with a monoclonal antibody against ECA.

Antigens, Bacterial↗
PubMed1986

Speciation, serotyping, antimicrobial sensitivity and plasmid content of Proteeae from the environment of calf-rearing units in South West England.

A survey was undertaken of the occurrence, serotype, antimicrobial sensitivity and plasmid content of members of the tribe Proteeae in the environment of two calf-rearing units in the county of Avon in South West England. Examples of the following species were found: Proteus mirabilis, Prot. vulgaris, Prot. vulgaris Biogroup 2, Morganella morganii, Providencia stuartii, Prov. alcalifaciens and Prov. rettgeri. A wide range of serotypes was found, many having been previously reported from nosocomial isolates. A total of 15% of isolates carried plasmids; six pairs of isolates were identified which had identical serotypes but different patterns of plasmid carriage. The antimicrobial sensitivity of the isolates was generally similar to isolates of Proteeae from humans. Although no truly aminoglycoside-resistant isolates were found, some isolates of Prov. stuartii and Prov. rettgeri had MIC's higher than the other isolates to gentamicin and netilmicin, suggesting the presence of low levels of the enzyme AAC 2'. The study demonstrates that there is a considerable diversity of species and types of Proteeae associated with calves and their environment. It seems likely that a potential cause of colonization of the human gut by Proteeae is the consumption of meat.

Animals↗
PubMed1986

Distribution of sero-biotypes of Campylobacter jejuni and C. coli isolated from paediatric patients.

During a one-year period, 258 isolates of Campylobacter jejuni and C. coli were obtained from children with gastroenteritis or bacteraemia at the Red Cross Children's Hospital, Cape Town, South Africa. These isolates were biotyped by hippurate hydrolysis, H2S production and tolerance to 2,3,5-triphenyltetrazolium chloride (TTC). Our study indicated that 95.4% of the isolates were C. jejuni biotype 1, 1.5% were C. jejuni biotype 2 and 3.1% were C. coli; 70% of the isolates were resistant to TTC. Serotyping on the basis of soluble, thermostable antigens detected by a passive-haemagglutination technique revealed that 79% of the Cape Town isolates were typable and that the most common serotypes, in order, were: 4, 2, 12, 23/36 and 19, together comprising 25% of the isolates. About 37% of the typable isolates belonged to nine serotypes. The finding that 21% of the isolates were non-typable suggests the existence of antigenic specificities different from those defined by the 60 antisera in current use.

Campylobacter↗
PubMed1986

Effects of erythromycin and ciprofloxacin on chronic fecal excretion of Campylobacter species in marmosets.

Ciprofloxacin was compared with erythromycin for the eradication of Campylobacter species that were chronically excreted in the stools of marmosets (Saguinus labiatus labiatus, Saguinus fuscicollis nigrifrons, and Saguinus fuscicollis illigeri). Stool cultures were negative within 48 h of the beginning of treatment with either agent. Within 10 days after the end of therapy, however, Campylobacter species were again isolated from the stools of six animals that had received erythromycin. During an 8-week follow-up period, no animal that had received ciprofloxacin relapsed. High levels of ciprofloxacin in the stool (mean, 49.2 micrograms/g) possibly contributed to the efficacy of this agent.

Animals↗
PubMed1986

Isolation and characterization of a common antigen in Campylobacter jejuni and Campylobacter coli.

Flagellin protein was isolated and purified from two serotype reference strains of Campylobacter jejuni, Pen 1 and Pen 3. Each preparation was shown by sodium dodecyl sulfate-polyacrylamide gel electrophoresis to consist of a diffuse band with a molecular mass of approximately 62 kilodaltons. Antisera were prepared against flagellin from Pen 1, and specific antibody was isolated by affinity chromatography with flagellin protein covalently bound to cyanogen bromide-activated Sepharose. The high-affinity antibody was used to immune blot purified flagellin from Pen 1 and Pen 3, as well as whole-cell preparations and acid-glycine extracts from the 60 reference strains of the thermostable antigen serotyping system. From each of the 60 strains, a protein with a molecular mass of approximately 62 kilodaltons was identified which shared a common antigenic determinant. When the affinity-purified antibody was used in a coagglutination assay, washed whole cells were not agglutinable unless they had been pretreated with an acid buffer (glycine-hydrochloride [pH 2.0]). This indicated that the antigenic determinant common to strains of both C. jejuni and Campylobacter coli may not be exposed in the native state.

Agglutination Tests↗
PubMed1986

Antibody response in patients infected with one common strain of Campylobacter jejuni. Evidence for production of antibodies against thermostable soluble antigens.

Antibody production was investigated for ten patients from a group of 20 who had contracted infections with a strain of Campylobacter jejuni of serotype PEN 6,7. Production of antibody was determined by titrating ten sets of paired sera for agglutination of formalin-treated and heat-treated cell suspensions and by passive hemagglutination using both sheep and human O Rh-red blood cells sensitized with extracted soluble thermostable antigens. All patients had demonstrable antibodies against the formalin-treated cells, six had a four-fold or greater increase in antibody levels. Nine patients showed antibodies against the heat-inactivated cells of whom five showed a fourfold or greater rise in antibody levels. Three patients developed antibodies against the extracted thermostable antigens. Sera from 100 blood donors served as controls. Six paired sera from patients that had antibodies against the heated suspension were analyzed by an immunofluorescence technique for determining IgM, IgA and IgG antibodies against live and heat-inactivated bacteria. Each of the six sera displayed antibody response primarily of the IgM and IgA class with highest levels against live cell suspensions.

Antibodies, Bacterial↗
PubMed1985

Serotyping of Campylobacter jejuni isolated from sporadic cases and outbreaks in northern Norway.

In the northern regions of Norway, 123 cases of Campylobacter jejuni gastroenteritis were either sporadic infections or due to five separate outbreaks during 1980-83. Using a serotyping scheme based on thermostable antigens and the passive haemagglutination technique, 92 isolates were serotyped. Excluding duplicates from the outbreaks, the serotype distribution based on 79 isolates showed that serotypes 6, 7 and 12, 40 were the most frequent in occurrence. Each included 11 (13.9%) of the isolates and each serotype was also identified twice as the epidemic strain in four different outbreaks. A fifth outbreak strain was serotype 13, 16, 50. The number of isolates that reacted in one or more antisera of the cross reacting group of serotypes 4, 13, 16, 43 and 50 was 21 (26.6%). The other 23 isolates fell into 19 other serotypes and 13 (16.5%) were untypable.

Campylobacter Infections↗
PubMed1985

Basis for serological heterogeneity of thermostable antigens of Campylobacter jejuni.

Lipopolysaccharides (LPS) were extracted from eight strains of Campylobacter jejuni and purified by enzyme treatment to remove traces of RNA, DNA, and protein. This material was used to sensitize sheep erythrocytes for the passive hemagglutination assay that is presently used to serotype C. jejuni. The results confirmed that the thermostable antigen typing scheme is based on LPS (O) antigens. The LPS after sodium dodecyl sulfate-polyacrylamide gel electrophoresis and silver staining was found to consist of a series of slow migrating bands which could not be eliminated by treatment with NaOH, urea, or EDTA. However, the use of LPS double labeled with 14C and 32P yielded evidence that the bands of high molecular weight were indeed aggregations of low-molecular-weight LPS molecules.

Antigens, Bacterial↗