Biomedical subjects

D W Lambe

Publications and source records attributed to D W Lambe.

At least 37 records · Page 2Linked to original sources

PubMed1986

An electron microscopic study of the effect of clindamycin therapy on bacterial adherence and glycocalyx formation in experimental Staphylococcus aureus osteomyelitis.

After induction of experimental osteomyelitis with Staphylococcus aureus in a rabbit tibia model, clindamycin phosphate (280 mg/kg/day) was used to treat the infected animals for 1, 2 and 3 week periods. Scanning electron microscopy of samples of infected bone tissue taken at necropsy revealed masses of coccoid profiles embedded in a matrix of condensed exopolysaccharide material which adhered to the bone in both infected control animals and in infected animals treated for 1 week with clindamycin phosphate. After 2 and 3 weeks of clindamycin phosphate treatment, the infecting bacteria could not be cultured from tissue samples, and scanning electron microscopy of these samples revealed few coccoid profiles adhering to the bone and marrow. Radiological, microbiological, clinical, histological and electron microscopic findings all indicated recovery from the diseased state with increased length of clindamycin phosphate treatment.

Animals↗

PubMed1984

Bacterial adherence and glycocalyx formation in osteomyelitis experimentally induced with Staphylococcus aureus.

A surgical procedure allowed the placement of a silicone rubber catheter in the marrow cavity of the tibia of a rabbit and also allowed the introduction of a sclerosing agent (sodium morrhuate) and cells of Staphylococcus aureus. Osteomyelitis developed in 60% of the animals so treated, and the infecting microorganism was recovered from the infected tibias of the animals that developed this disease. All blood cultures taken 24 h after the infection were negative for S. aureus. Radiological findings consisted of osteolytic changes, the occurrence of sequestration and periosteal reactions, and sclerosis in the infected bones. Sections of bone prepared for histological examination confirmed the diagnosis of osteomyelitis. Transmission and scanning electron microscopy of samples of bone marrow, bone chips, and the catheters taken from the infected tibiae revealed gram-positive cocci embedded in a very extensive matrix of ruthenium red-staining glycocalyx adhering to the bone and the implanted catheter. It is proposed that this extensive glycocalyx served a protective function for the bacteria and was important in bacterial adherence and thus played an important role in bacterial persistence and the development of osteomyelitis in these rabbits.

Adhesiveness↗

PubMed1984

Differentiation of Campylobacter species by protein banding patterns in polyacrylamide slab gels.

Soluble protein extracts of 37 catalase-positive strains of Campylobacter species were examined by polyacrylamide slab gel electrophoresis (PAGE). Electrophoretic banding patterns showed good correlation with biochemical tests and with available DNA homology data in distinguishing species of Campylobacter but did not differentiate subspecies or biotypes. PAGE patterns indicated that Campylobacter coli is a distinct species. Furthermore, the PAGE patterns indicated that C. jejuni and nalidixic acid-resistant thermophilic Campylobacter species (C. laridis) are each distinct species. The protein banding patterns of C. fetus subsp. venerealis and C. fetus subsp. fetus strains were distinctly different from those of the three thermophilic species.

Bacterial Proteins↗

PubMed1984

Morphological stabilization of the glycocalyces of 23 strains of five Bacteroides species using specific antisera.

Cells of five Bacteroides species were examined following treatment with homologous antisera and staining with ruthenium red. They were enveloped by glycocalyces and these extensive fibrous exopolysaccharide matrices were fully retained as an integral "capsule" by some cells, while other cells showed "capsule" as well as detached glycocalyx components forming an intercellular "slime.". These extensive glycocalyces collapsed during dehydration for electron microscopy and formed electron-dense accretions on cell surfaces and electron-dense reticula in intercellular spaces when the cells were treated with heterologous antiserum or when antibody stabilization was omitted. The glycocalyces of all strains, both stabilized and unstabilized, were observed outside the outer membranes of cell walls that showed the "classic" gram-negative structural organization. Appropriate modifications of the indirect fluorescent antibody test demonstrated an integral "capsule" on all strains examined; detached glycocalyx and varying amounts of slime were demonstrated after stabilization with homologous, but not heterologous, antiserum.

Antibody Specificity↗

PubMed1983

Production of phenylacetic acid by Bacteroides melaninogenicus ssp. intermedius serogroup C-1.

The methyl derivatives of broth cultures of black-pigmented Bacteroides were examined by gas chromatography for production of phenylacetic acid. Two serogroups of B. melaninogenicus ssp. intermedius described by Lambe differed in the ability to produce phenylacetate. Serogroup C failed to produce phenylacetic acid while serogroup C-1 produced small amounts of phenylacetate, which contributed 2.2-5.7% to the total nonvolatile acid profile. Holdeman's newly proposed species "B. intermedius" and "B. corporis" correspond to serogroups C and C-1, respectively. These data support the elevation of the two serogroups of B. melaninogenicus ssp. intermedius to species status. Bacteroides gingivalis produced phenylacetate in significantly larger quantities than B. corporis. Bacteroides melaninogenicus ssp. melaninogenicus, "B. melaninogenicus ssp. levii," and B. asaccharolyticus did not produce phenylacetic acid. These results indicate that phenylacetic acid production may be useful in distinguishing "B. corporis" and B. gingivalis from the other black-pigmented Bacteroides.

Bacteroides↗

PubMed1982

Characterization of Bacteroides gingivalis by direct fluorescent antibody staining and cellular fatty acid profiles.

Bacteroides gingivalis is a newly proposed species which includes strains isolated from the mouth. Thirteen strains of B. gingivalis isolated from three geographic locations in the United States and France were examined with direct fluorescent antibody staining and analysis of total cellular fatty acids and compared with 16 strains of B. asaccharolyticus of nonoral origin by the same methods. Bacteroides gingivalis strains reacted with the B. gingivalis conjugate (fluorescein isothiocyanate labeled antibody reagent) only, while the B, asaccharolyticus strains reacted with the B. asaccharolyticus conjugate only. The B. gingivalis strains showed negative fluorescence with fluorescein isothiocyanate conjugates for other black-pigmented Bacteroides species. The specificity of the B. gingivalis conjugate was demonstrated by its failure to stain 88 strains of aerobic and anaerobic bacteria other than B. gingivalis. The fatty acid profiles of B. gingivalis and B. asaccharolyticus were readily distinguishable. The B. gingivalis profile was also distinguishable from those of other pigmenting Bacteroides species on the basis of concentration ratios among the characteristic components. These results support the species separation of B. gingivalis and B. asaccharolyticus. Further, they indicate the usefulness of cellular fatty acid profiles as an adjunct to the use of specific fluorescent antibody conjugates for identification of Bacteroides species.

Bacteroides↗

PubMed1981

Outbreak of acute pulmonary histoplasmosis in members of a wagon train.

In August 1980, an outbreak of acute pulmonary histoplasmosis occurred among participants in a wagon train as it traveled through eastern Tennessee. Of the 85 people on the train 69 (81 percent) had evidence of infection with Histoplasma capsulatum. Fifty-four people had symptomatic disease. The source of infection was traced to the site of a former winter blackbird roost in Charleston, Tennessee, that had been partially cleared five years earlier to make a park. Fourteen of 25 soil samples from this site were culture-positive for H. capsulatum. This is the first reported outbreak to involve a large migrant group. The outbreak is unusual in that exposure occurred without excavation, construction or tree-cutting at the site.

Adult↗

PubMed1981

Campylobacter fetus ssp jejuni: isolation from patients with gastroenteritis.

Within a seven-month period, Campylobacter fetus ssp jejuni was isolated in East Tennessee from 18 patients with gastroenteritis; 83% of these patients had bloody diarrhea. Absence of other enteric organisms such as Salmonella, Shigella, and Yersinia implicated C fetus ssp jejuni as the causative agent. A fourfold increase in titer by tube agglutination from four of eight patients studied supported the pathogenicity of this organism. Treatment with erythromycin alleviated gastroenteritis symptoms within 24 to 48 hours, with concurrent disappearance of the organism from the feces. An isolation rate of 8% in our patients indicates that C fetus ssp jejuni is more common as a cause of human diarrhea than Salmonella or Shigella. The severity of the C fetus ssp jejuni gastroenteritis poses a possible reclassification from diarrhea or gastroenteritis to acute dysentery syndrome.

Adult↗

PubMed1979

Characterization of a polyvalent conjugate of Bacterroides fragilis by fluorescent antibody staining.

A polyvalent conjugate (fluorescein-isothiocyanate-labeled antibody reagent) prepared for Bacteroides fragilis contained conjugates prepared against three strains of B. fragilis. This conjugate stained 93% of the 111 B. fragilis test strains; the other 7% of B. fragilis stained at certain times but not others. The conjugate was specific for B. fragilis, 91 strains of anaerobes other than B. fragilis and aerobes failed to give a positive fluorescence. The advantage of this conjugate is that it provides a quicker and less expensive identification of B. fragilis than the use of pre-reduced biochemical media and gas chromatography.

Bacteroides fragilis↗

PubMed1979

Serologic studies of Streptococcus intermedius, Streptococcus constellatus, and Streptococcus morbillorum by crossed immunoelectrophoresis.

A reference antigen-antibody system for Streptococcus intermedius, Streptococcus constellatus, and Streptococcus morbillorum was established with crossed immunoelectrophoresis. A comparison of S. intermedius, S. constellatus, and S. morbillorum with crossed immunoelectrophoresis and crossed immunoelectrophoresis with intermediate gel indicated that S. intermedius and S. constellatus are closely related antigenically with as many as six common cytoplasmic antigens. S. morbillorum was antigenically more distinct; antiserum of one strain of S. morbillorum was monospecific, indicating that specific serogroups of S. morbillorum exist. Crossed immunoelectrophoresis and tandem crossed immunoelectrophoresis revealed that S. intermedius, S. constellatus, and S. morbillorum also share some common antigens with Streptococcus sanguis and Streptococcus mitis, but S. intermedius, S. constellatus, and S. morbillorum are antigenically distinct from Streptococcus mutans and Streptococcus bovis.

Antibodies, Bacterial↗

PubMed1976

Corynebacterium vaginale (Haemophilus vaginalis) in women with leukorrhea.

Corynebacterium vaginale was recovered from vaginal-cervical swab specimens in 164 of 288 women with leukorrhea and in four of 30 women without signs or symptoms of lower genital tract infection. The amount and character of the leukorrhea observed in association with C. vaginale infection were variable; in typical cases the discharge had the appearance of a thin paste. In a series of 100 patients studied to determine the apparent causes of leukorrhea, noninfectious causes were inferred in seven patients and no cause ascertained in six. Candida or other yeasts, C. vaginale, and Trichomonas vaginalis were identified alone or in combination in 87 patients; 53 had yeasts, 35 had C. vaginale, and 15 had T. vaginalis.

Adolescent↗

PubMed1976

Susceptibility testing of anaerobic bacteria with 100-microg carbenicillin disks.

A total of 245 strains of anaerobic bacteria were examined for their susceptibility to carbenicillin by the disk test method and by minimum inhibitory concentration (MIC) determinations. Standard-curve studies with a strain of Bacteroides fragilis subsp. fragilis that was minimally susceptible to carbenicillin and Escherichia coli (ATCC 25922) demonstrated that a disk containing 100 mug of carbenicillin was suitable for testing susceptibility of anaerobes to carbenicillin. Thus, the diameter of zones around the 100-mug carbenicillin disks and MIC values were determined under the following test conditions: Mueller-Hinton agar supplemented with sheep blood, vitamin K(1), and hemin; an incubation temperature of 35 C; and an atmosphere of 80% N(2), 10% H(2), and 10% CO(2). The strains were separated into two populations by correlating zone diameters and geometric mean MICs. The disk test more clearly separated the resistant and susceptible populations and was more reproducible than the MIC test. Thus, a statistical analysis based on the distribution of zone diameters of susceptible and resistant strains was used to derive an interpretive scheme for anaerobic bacteria tested with 100-mug carbenicillin disks. The following interpretive scheme is recommended for testing anaerobes with 100-mug disks of carbenicillin: resistant, 8 mm or less; indeterminate, 9 to 12 mm; and susceptible, 13 mm or greater.

Anaerobiosis↗

PubMed1976

Clinical comparison of aerobic, hypertonic, and anaerobic culture media for the radiometric detection of bacteremia.

The BACTEC 225 was used to test 5,811 routine blood cultures over a 20-month period. Aerobic, anaerobic, and hypertonic media were employed. The BACTEC 225 detected 511 positive cultures; 407 of these were considered significant organisms, and 104 were presumed contaminants. Of the significant positive cultures, 15% were detected within the first 12 h of incubation, 52% within 24 h, 82% within 48 h and 92% within 72 h. Aerobic, anaerobic, and hypertonic media are recommended for each venipuncture since 56 cultures were isolated from the aerobic medium only, 110 from the anaerobic medium only, and 94 from the hypertonic medium only. There were 16 patients who had multiple venipunctures from which organisms were repeatedly isolated from only one medium: two from the aerobic medium, four from the anaerobic medium, and ten from the hypertonic medium only. Detection times were not significantly different for the aerobic and hypertonic media. However, there were five patients with multiple venipunctures in which growth was detected radiometrically at least 48 h earlier in the hypertonic than in the aerobic medium. False-positive growth index readings were noted in 1,085 (19%) of the aerobic vial, 11 (0.19%) of the anaerobic vials, microorganisms were isolated from at least one of the companion vials. Using 5% co2 to flush the aerobic vials. With some false-positive aerobic and hypertonic vials decreased the number of false positives to about 6% of the total.

Aerobiosis↗

PubMed1976

Description of a polyvalent conjugate and a new serogroup of Bacteroides melaninogenicus by fluorescent antibody staining.

A polyvalent conjugate (fluorescein isothiocyanate-labeled antibody reagent) containing serogroups A, B, and C conjugates was prepared. This polyvalent conjugate gave a positive fluorescent antibody (FA) stain with 49 stains of Bacteroides melaninogenicus representing serogroups A, B, and C. When additional strains (92 strains) of the three subspecies of B. melaninogenicus were examined by the FA stain, with A, B, and C, and polyvalent conjugates, nine strains of B. melaninogenicus subsp. intermedius failed to give a positive stain with any conjugate. Therefore, an FA conjugate was prepared with the antiserum to one of these strains (532-70A); all nine strains stained positively with this conjugate. These nine strains were biochemically characteristic of B. melaninogenicus subsp. intermedius; thus, these strains were designated as a new serogroup, serogroup C-1. A new polyvalent conjugate containing serogroups A, B, C, and C-1 was prepared. This polyvalent conjugate stained positively with 23 representative strains from serogroups A, B, C, and C-1. The new conjugates failed to stain positively with other anaerobes and aerobes tested. The four individual conjugates, as well as the polyvalent conjugate, may be used for a more rapid identification of B. melaninogenicus than is possible by biochemical testing.

Bacteroides↗

PubMed1976

Serogrouping of Bacteroides fragilis subsp. fragilis by the agglutination test.

The agglutination technique was used to establish a serological classification scheme for 98 strains of Bacteroides fragilis subsp. fragilis isolated from clinical specimens and normal human feces. Absorbed antisera were prepared to seven strains of B. fragilis subsp. fragilis. These seven absorbed antisera were species as well as subspecies specific and provided the basis of the serological classification scheme. This scheme was composed of 21 serogroups; seven of these serogroups contained only one group component. There was a total of 45 serological patterns. This serological scheme may be used for the serological classification of strains of B. fragilis subsp. fragilis and to study the epidemiology of this organism.

Agglutination Tests↗

PubMed1976

Epidemiologic characteristics of women infected with Corynebacterium vaginale (Haemophilus vainalis).

In a group of 184 women infected with Corynebacterium vaginale (Haemophilus vaginalis), 34% over age 30 were divorced or separated and 8% gave a history of induced abortion. Fifty-one percent were taking an oral contraceptive drug, as compared to 36% of 140 women in a control group. Various sexually transmitted diseases were diagnosed either concomitantly or at another time in 52% of women in the study group and 38% of those in the control group. The rate of cervical neoplasia (invasive carcinoma, carcinoma in situ, and dysplasia) was 13.6% in the study group and 5.7% in the control group, the rate in the study group being several times that in the general population. These and other available epidemiologic data support the conclusion that C vainale is transmitted sexually.

Adolescent↗

PubMed1975

Immune responses in eight patients infected with Bacteroides fragilis.

Sera from eight patients with either septicemia or pyothorax caused by Bacteroides fragilis were assayed for specific antibody by the agglutination, immunofluorescence, and agar gel diffusion techniques. Antibodies were detected in the sera of all eight patients by all three serological tests employed; titers as high as 1:160 and 1:320 were detected by the agglutination test and the immunofluorescence technique, respectively, and all patients had precipitating antibody. Failure of B. fragilis sub-species thetaiotaomicron to react with any heterologous antisera from the other seven patients infected with B. fragilis subspecies fragilis thetaiotaomicron was not serologically related to any of the other strains studied. Demonstration of an immune response to anaerobic infection supported the pathogenesis of anaerobes in infectious disease processes and indicated the possible diagnostic role that serological tests may serve in the diagnosis of anaerobic infections in humans.

Adult↗

PubMed1974

Proposed standardized method for testing and interpreting susceptibility of Bacteroides fragilis to tetracycline.

One hundred twenty-four strains of Bacteroides fragilis were examined for susceptibility to tetracycline disks and by minimal inhibitory concentration (MIC) determinations. MIC values and zone sizes around 30-mug tetracycline disks were determined by using selected test conditions which included Mueller-Hinton agar supplemented with sheep blood, vitamin K, and hemin and an incubation temperature of 35 C in an atmosphere of 80% N(2), 10% H(2), and 10% CO(2). Strains were separated into two distinct populations by geometric mean MIC and dis tests. Of the 124 strains, 78 were resistant and 46 were susceptible. The resistant strains had geometric mean MIC's of 8 mug/ml or greater, whereas the geometric mean MIC's of sensitive strains were 5 mug/ml or less. The disk test proved to be more reproducible than the MIC test and completely separated the resistant and susceptible populations. An interpretive scheme for B. fragilis to tetracycline was statistically derived on the basis of the distribution of zone sizes of susceptible and resistant strains: resistant, 18 mm or less; indeterminant, 19 to 20 mm; and susceptible, 21 mm or greater. These zone sizes compared closely with the Kirby-Bauer criteria for aerobic bacteria.

Anti-Bacterial Agents↗