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B E Anderson

Publications and source records attributed to B E Anderson.

At least 37 records · Page 2Linked to original sources
PubMed1999

Roles of glycoproteins and oligosaccharides found in human vaginal fluid in bacterial adherence.

Adherence of type 1-piliated Escherichia coli to carbohydrate structures of vaginal mucosa plays a major role in the pathogenesis of ascending urinary tract infections in women. Colonization of the vaginal introitus is influenced by interactions between pathogens, vaginal fluid, and vaginal epithelium. In this study, the type and amount of carbohydrates and glycoproteins present in vaginal fluid were determined. Free and protein-bound oligosaccharides in vaginal fluid specimens were analyzed by fluorophore-assisted carbohydrate electrophoresis (FACE) and high-pressure liquid chromatography (HPLC). Two-dimensional electrophoretic separations of vaginal fluid glycoproteins were performed together with bacterial overlay assays. The results of FACE showed that the majority of the oligosaccharides are in the free state and the bound oligosaccharides are undetectable. HPLC analysis of free sugars revealed glucose as the major sugar (3.3 +/- 0.3 mM), and the concentrations of mannose and glucosamine were 0.065 +/- 0.04 and 0.02 +/- 0.001 mM, respectively. Radiolabeled E. coli bound three vaginal fluid glycoproteins with the following molecular masses and pIs: 82 kDa and pI 5.5, 55 kDa and pI 4.5, and 55 kDa and pI 6.5. The binding was inhibited by mannose and by deglycosylation of the proteins prior to the overlay assay. One of these putative receptors was identified to be the heavy chain of secretory IgA (S-IgA). These data suggest that the free mannose in the fluid is less than that required to affect E. coli-epithelial cell binding interactions and that S-IgA may bind E. coli in the vaginal introitus.

Adult↗
PubMed1999

A holistic approach to environmental health research.

One of the most formidable questions facing the environmental health research community today is how to translate basic fundamental research into a product (e.g., disease outcome) that meets the needs of its stakeholders--the medical community, regulatory agencies, and ultimately, the citizens of our nation. Historically, a successful research program could be defined as one that received continuous funding, produced high-quality publications, and was respected by scientists in related fields. However, it is now apparent that this is not sufficient for attaining improved public health--the ultimate goal of these research efforts. Research results must be transferred in a more active way to the communities and professionals who have need of this information. The link must be recognized, and the roles of the stakeholders in the entire research process must be acknowledged to ensure full impact of the research endeavors.

Environmental Health↗
PubMed1998

Outer membrane proteins of Bartonella henselae and their interaction with human endothelial cells.

Members of the genus Bartonella are unique in that they are bacteria which cause proliferation of microvascular endothelial cells and neovascularization (angiogenesis). The mechanisms by which Bartonella henselae causes these processes are unknown. Given the importance of surface-exposed determinants in the pathogenesis of many organisms, outer membrane proteins (OMPs) of B. henselae were identified. Enrichment of the outer membrane fraction of B. henselae by sarkosyl treatment of total membranes, together with radioiodination and biotinylation of intact organisms, suggest that at least nine proteins, with molecular weights of 28, 30, 35, 43, 58, 61, 79, 92 and 171 kDa, are located in the outer membrane. Triton X-100-extracted biotinylated human umbilical vein endothelial cell (HUVEC) surface proteins bound to the 43 kDa B. henselae OMP after B. henselae whole-cell lysates and sarkosyl-fractionated OMPs were separated by SDS-PAGE and transferred onto nylon. Biotinylated B. henselae surface proteins of 28, 32, 43, 52 and 58 kDa were shown to bind intact HUVEC, with the 43 kDa protein being the major adhesin. Preincubation of HUVEC with an increasing concentration (20 microg/ml to 4 mg/ml) of sarkosyl-fractionated unlabelled B. henselae outer membrane proteins inhibited the attachment of all identified HUVEC binding proteins. The identification of B. henselae OMPs, as well as adhesins, should provide a basis for further investigation of the role of adherence in the pathogenesis of B. henselae.

Adhesins, Bacterial↗
PubMed1998

Conversion of native oligomeric to a modified monomeric form of human C-reactive protein.

C-reactive protein (CRP) is a pentameric oligoprotein composed of identical 23 kD subunits which can be modified by urea-chelation treatment to a form resembling the free subunit termed modified CRP (mCRP). mCRP has distinct physicochemical, antigenic, and biologic activities compared to CRP. The conditions under which CRP is converted to mCRP, and the molecular forms in the transition, are important to better understand the distinct properties of mCRP and to determine if the subunit form can convert back to the pentameric native CRP form. This study characterized the antigenic and conformational changes associated with the interconversion of CRP and mCRP. The rate of dissociation of CRP protomers into individual subunits by treatment in 8 M urea-10 mM EDTA solution was rapid and complete in 2 min as assayed by an enzyme-linked immunofiltration assay using monoclonal antibodies specific to the mCRP. Attempts to reconstitute pentameric CRP from mCRP under renaturation conditions were unsuccessful, resulting in a protein retaining exclusively mCRP characteristics. Using two-dimensional urea gradient gel electrophoresis, partial rapid unfolding of the pentamer occurred above 3 M urea, a subunit dissociation at 6 M urea, and further subunit unfolding at 6-8 M urea concentrations. The urea gradient electrophoresis results suggest that there are only two predominant conformational states occurring at each urea transition concentration. Using the same urea gradient electrophoresis conditions mCRP migrated as a single molecular form at all urea concentrations showing no evidence for reassociation to pentameric CRP or other aggregate form. The results of this study show a molecular conversion for an oligomeric protein (CRP) to monomeric subunits (mCRP) having rapid forward transition kinetics in 8 M urea plus chelator with negligible reversibility.

C-Reactive Protein↗
PubMed1997

Bartonella spp. as emerging human pathogens.

Members of the genus Bartonella (formerly Rochalimaea) were virtually unknown to modern-day clinicians and microbiologists until they were associated with opportunistic infections in AIDS patients about 6 years ago. Since that time, Bartonella species have been associated with cat scratch disease, bacillary angiomatosis, and a variety of other disease syndromes. Clinical presentation of infection with Bartonella ranges from a relatively mild lymphadenopathy with few other symptoms, seen in cat scratch disease, to life-threatening systemic disease in the immunocompromised patient. In some individuals, infection manifests as lesions that exhibit proliferation of endothelial cells and neovascularization, a pathogenic process unique to this genus of bacteria. As the spectrum of disease attributed to Bartonella is further defined, the need for reliable laboratory methods to diagnose infections caused by these unique organisms also increases. A brief summary of the clinical presentations associated with Bartonella infections is presented, and the current status of laboratory diagnosis and identification of these organisms is reviewed.

Animals↗
PubMed1996

[Human ehrlichiosis: report of the 1st case in Venezuela].

Human ehrlichiosis is a zoonotic disease, caused by a rickettsia that infects leukocytes. It was described for the first time in the United States of America in 1986. More than 300 cases have been reported in that country. One case has been reported in Portugal, two in France and one more in a tourist coming from Mali (Africa). In Venezuela, a tropical country, where ehrlichiosis is endemic in dogs and horses, the first case of human ehrlichiosis is reported in a seventeen month old girl. She initially had symptoms compatible with a viral illness. Then she developed a rash, acute respiratory failure, hepato-splenomegaly, neurologic abnormalities, renal failure and hematologic alterations including pancytopenia and disseminated intravascular coagulation (DIC). Different diagnoses were given before it was concluded that it was a case of ehrlichiosis. She was treated with tetracycline and very soon recovered. The initial diagnosis was made using buffy coat blood smears stained with Diff Quick Stain. Indirect Immunofluorescence (IFA) test was used to detect antibodies against Ehrlichia chaffeensis (1:126) but not to other rickettsias. Also the presence of platelets with ehrlichia bodies similar to E. platys from dogs, it was demonstrated, in peripheral blood from the child. The presence of these bodies in human platelets has not been previously reported. In this case, it could not be proved that the disease was transmitted by a tick bite. The presence of ehrlichia bodies in platelets from the girl's peripheral blood is also described.

Adolescent↗
PubMed1995

An immunofiltration apparatus for accelerating the visualization of antigen on membrane supports.

Although proteins can be transferred and bound to a membrane with several different methods such as capillary transfer, electroblotting, etc., only the "shaker/incubation" method is commonly used for visualization of the proteins. We have tested an apparatus for the immunofiltration of solutions through nitrocellulose membrane which greatly accelerates the kinetics for the visualization of proteins. As a model system, avidin, bound on nitrocellulose membrane, was detected with 5-min filtering steps of a 1:2000 dilution of ascites of murine monoclonal antibody against avidin followed by a 1:5000 dilution of goat anti-mouse IgG-horseradish peroxidase and 0.5 mg/ml chloronapthol in the presence of 0.01% peroxide. The same solutions used with 5-min incubation steps with the shaker/incubation method could not detect avidin at almost 10 times that amount. Further studies with monoclonal antibodies specific for native C-reactive protein and modified-CRP, 15.1D6 and 13.3H12 respectively, showed that immunofiltration did not result in altered specificity compared to the shaker/incubation method. Also, data are presented showing the advantages of a 10-slot top for the immunofiltration of solutions through distinct areas of a membrane.

Antibodies, Monoclonal↗
PubMed1995

Protection of guinea-pigs from experimental Rocky Mountain spotted fever by immunization with baculovirus-expressed Rickettsia rickettsii rOmpA protein.

Baculovirus recombinants that express the Rickettsia rickettsii rOmpA protein were constructed. Monoclonal antibodies (mAbs) against the rOmpA protein reacted with recombinant-infected Spodoptera frugiperda (Sf9) cells in indirect immunofluorescence assays. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting of infected Sf9 cell lysates with a mAb against rOmpA showed that the recombinant-expressed rOmpA protein migrated slightly below rOmpA extracted from R. rickettsii. Guinea-pigs immunized with lysates of recombinant-infected Sf9 cells developed antibodies reactive with R. rickettsii and were protected against challenge, indicating that the baculovirus-expressed rOmpA protein could be useful in subunit vaccines and for studies of the immune response to R. rickettsii infection.

Animals↗
PubMed1995

Cat-scratch disease in Hawaii: etiology and seroepidemiology.

OBJECTIVE: To study the etiology and seroepidemiology of cat-scratch disease (CSD) in Hawaii. METHODS: Blood and fine-needle aspirate (FNA) from the lymph nodes of 39 consecutive patients with clinical CSD were cultured for Bartonella henselae, and blood samples from index cats, stray cats, and dogs were cultured and their sera were tested by indirect fluorescence antibody test for antibodies to B. henselae and Afipia felis. Sera from age- and sex-matched human subjects without cat exposure served as controls. RESULTS: Warthin-Starry staining showed positive results in only 4 of 32 FNAs, and B. henselae was isolated from only one FNA specimen. All of 38 patients who had two or more sera tested had elevated titers of antibody to B. henselae. Only 1 of 48 human control sera had antibody to B. henselae. Of 31 kittens, 21 had positive blood culture results and elevated antibody titers to B. henselae. Of three adult cats, all had negative blood culture results, but they had serologic evidence of past infection. Of 23 adult stray cats, 18 had elevated titers of antibody to B. henselae, but in only one was the blood culture result positive. Results of IFA tests were marginally positive for A. felis in 1 of 29 patients with CSD and in one adult stray cat and one dog. CONCLUSIONS: This study shows that the B. henselae IFA test is both highly sensitive and specific for the detection of infection caused by B. henselae and for the laboratory diagnosis of CSD, and that FNA is seldom helpful in confirming the diagnosis. We further demonstrated that CSD in Hawaii is due to B. henselae and that infection is directly linked to the scratch or bite of a kitten. Older cats seldom have bacteremia but often have serologic evidence of past infection. Our study fails to implicate dogs in the epidemiology of CSD in Hawaii, and A. felis was not etiologically implicated in CSD in the human subjects and animals we studied.

Adolescent↗
PubMed1995

Bartonella henselae endocarditis in an immunocompetent adult.

We describe a case of aggressive Bartonella henselae endocarditis in an immunocompetent man who owned a cat. Aortic valve replacement was required, and his infection was diagnosed by histology, serology, and polymerase chain reaction analysis. The manifestations of his disease included mediastinal lymphadenopathy, glomerulonephritis, myocarditis, and a petechial rash; the unusual finding of a positive titer of c-antineutrophil cytoplasmic antibodies was noted. Serological titers were markedly elevated for > 1 year despite clinical improvement.

Adult↗
PubMed1995

Effect of vaginal fluid on adherence of type 1 piliated Escherichia coli to epithelial cells.

Colonization of the vaginal mucosa with uropathogens from fecal flora is an important step in ascending urinary tract infections (UTIs) in women. Colonization is influenced by interactions between uropathogens, vaginal fluid, and epithelial cells. In this study, vaginal fluid from 21 women was assessed for effects on adherence of type 1 piliated Escherichia coli to the A431 cell line. Adherence to cells was enhanced by all fluid specimens when tested at low fluid protein concentrations in an in vitro assay. At higher concentrations, certain specimens maintained enhanced binding whereas others resulted in diminished binding. Increases in adherence were associated with increased binding of E. coli to vaginal fluid in vitro and with higher vaginal fluid pH. These results demonstrate that vaginal fluid significantly alters the adherence of type 1 piliated E. coli to epithelial cells in vitro and, therefore, should be studied as a potential modifier in bacterial colonization and UTIs in vivo.

Adult↗
PubMed1995

Binding of type 1-piliated Escherichia coli to vaginal mucus.

To better understand the interactions involved in bacterial adherence and the role of mucus in the pathogenesis of urinary tract infections, we developed a system to study the binding of a recombinant Escherichia coli strain, HB101/pWRS1-17, expressing type 1 pili, to vaginal mucus collected from 28 women. Bacteria bound to differing extents to all specimens examined, and preincubation of bacteria with mannose inhibited binding by 50 to 89%. Additionally, all mucus samples showed reactivity with anti-mannose antibody, and the levels of reactivity correlated with the levels of bacterial binding, suggesting that the mannose-terminal saccharides present on these glycoproteins are the receptors for the binding of type 1-piliated bacteria. Mucus specimens collected over periods of 5 days and 12 weeks exhibited significant variation in bacterial binding, indicating temporal differences in the ability of vaginal mucus to act as a receptor for type 1-piliated E. coli. The results show that vaginal mucus can bind bacteria and may thus influence the initial attachment and subsequent colonization of the vaginal and urinary tract epithelium by E. coli.

Bacterial Adhesion↗
PubMed1994

Variation of blood group antigen expression on vaginal cells and mucus in secretor and nonsecretor women.

The expression of blood group antigens on the surface of urothelial cells and in mucus is controlled partly by the blood type and secretor status of the individual. To our knowledge, the possibility that the levels of these antigens vary with time has not been previously assessed. We determine if the pattern and/or intensity of blood group antigen expression on vaginal epithelial cells and mucus changed with time. Cell and mucus specimens were collected weekly for 3 months from 10 women: 5 (2 secretors and 3 nonsecretors) with and 5 (3 secretors and 2 nonsecretors) without a history of urinary tract infections. In addition, samples were collected on 5 consecutive days from 5 of these individuals. The cell and mucus samples were assayed for ABH and Lewis blood group antigens using monoclonal antibodies in cell concentration immunofluorescence and enzyme-linked fluorogenic assays, respectively. Although the pattern of antigen expression in the vaginal cell and mucus samples was consistent with the blood type and secretor status of an individual, in all women the level of antigen expression changed significantly and rapidly during the 3-month and 5-day periods. The results show a previously unrecognized phenomenon and demonstrate that the expression of blood group antigens on vaginal cells and in mucus is a dynamic process.

ABO Blood-Group System↗
PubMed1994

Blood group antigen expression on vaginal cells and mucus in women with and without a history of urinary tract infections.

Adherence of bacteria to carbohydrate receptors on the surface of vaginal epithelial cells is a critical event that precedes bacterial colonization of the vaginal mucosa and subsequent urinary tract infection. Blood group antigens, carbohydrate structures bound to lipids or proteins, constitute an important component of the uroepithelial cell membrane and may affect susceptibility to urinary tract infections. To determine if the ABH and Lewis antigen expression in women with a history of urinary tract infections differed from that of women without such a history, vaginal specimens from 87 women (42 patients and 45 controls) were analyzed for the detection of these antigenic determinants using monoclonal antibodies in quantitative immunoassays. The profile of ABH antigen expression was generally consistent with the ABO phenotype of the individual and appeared to be influenced by the secretor status. Secretors expressed higher levels of A, B and H determinants than nonsecretors. In addition, Lewis antigens were detected on vaginal cells and in mucus. Samples from nonsecretors expressed higher levels of Le(a) and Le(x) antigens, whereas secretors expressed higher levels of Le(b) and Le(y) antigens. The levels of antigen expression varied widely among individuals with the same blood type and secretor status. Comparisons between patient and control groups showed no significant differences in ABH or Lewis antigen expression overall, or when controlling for ABO or secretor phenotypes, respectively. These findings confirm our previous observations on healthy women, and document the heterogeneity of blood group antigen expression on vaginal epithelial cells and mucus from women with a history of urinary tract infections.

ABO Blood-Group System↗
PubMed1994

Effect of Lewis blood group antigen expression on bacterial adherence to COS-1 cells.

Epithelial cells from secretor individuals demonstrate decreased bacterial adherence compared with cells from nonsecretors. Lewis blood group antigen expression is one component of the secretor/nonsecretor phenotype and several epidemiologic studies have suggested a link between Lewis blood group antigen phenotype and susceptibility to urinary tract infections. In this study, we examined the possibility that the expression of the difucosylated Lewis blood group determinants, Leb and Ley (associated with the secretor phenotype), made cells less susceptible to Escherichia coli adherence by masking receptors for pili. COS-1 cells, which do not produce Lewis (Lea, Leb, Le(x), and Ley) blood group antigens, were used as target cells for bacterial adherence. The surface blood group antigen expression pattern of the cells was then modified by cotransfection with plasmids containing DNA inserts encoding alpha (1,2)-fucosyltransferase and alpha (1,3)- and alpha (1,4)-fucosyltransferases, resulting in the expression of Leb and Ley. E. coli HB101 expressing various adhesins (type 1, PapJ96, PapIA2, PapAD110, Prs, and S) from recombinant plasmids bound equally well to untransfected cells and transfected cells expressing Lea and Le(x) (nonsecretor phenotype) and Leb and Ley (secretor phenotype) antigens. We conclude that the presence of Leb and Ley antigens on cells from secretors does not alone mask receptors for E. coli pili or hinder bacterial adherence.

Animals↗
PubMed1994

Cultural, molecular, and immunological characterization of the etiologic agent for atypical canine ehrlichiosis.

More than 100 cases of canine ehrlichiosis, with three fatalities, were serologically negative by the indirect immunofluorescent antibody (IFA) test with Ehrlichia canis or E. sennetsu antigen but were reactive at titers of 10 to 640 with E. risticii. Ehrlichia-like agents were isolated from three such cases. The agents isolated from those cases were morphologically indistinguishable from each other and from a prototype, E. risticii, the etiologic agent of equine monocytic ehrlichiosis, in terms of growth characteristics and by light or electron microscopy. The patterns of and products from PCR were identical to those of E. risticii. The 16S rRNA sequences were distinct from those of E. canis and E. ewingii but were identical to those of E. risticii. A PCR product corresponding to the 5' half of the 16S rRNA gene was obtained from amplification of DNA from E. risticii and both sources of the atypical canine ehrlichiosis agent but was not obtained from uninfected host cells. The entire sequence of 719 nucleotides was identical for all three sources. The percentages of relatedness of the partial 16S rRNA gene of the atypical canine ehrlichiosis agent to E. risticii, E. sennetsu, E. platys, E. equi, E. phagocytophila, E. canis, E. chaffeensis, and E. ewingii were 100.0, 98.9, 83.7, 83.0, 83.0, 82.2, 81.8, and 81.5, respectively. These data are consistent with the identity of these isolates as E. risticii. The caninotropic characteristics of naturally acquired infections due to E. risticii are herein described for the first time, and the epizootiological implications are discussed in relation to the host range of E. risticii, which may include dogs as reservoirs.

Animals↗
PubMed1994

Disseminated cat-scratch disease: detection of Rochalimaea henselae in affected tissue.

An immunocompetent 9-year-old boy with disseminated cat scratch disease involving spleen, cervical and abdominal lymph nodes, skull, and one clavicle is reported. Antibodies to Rochalimaea quintana and R. henselae were detected, at increasing, then decreasing concentration. DNA extracted from the biopsied skull lesion was amplified by polymerase chain reaction and hybridized with species-specific oligonucleotides proving the presence of R. henselae in affected tissue. Our findings suggest that R. henselae plays a pathogenic role in cat-scratch disease.

Antibodies, Bacterial↗