Publications by authors named "Teresa Lagergard"

Haemophilus ducreyi and Klebsiella (Calymmatobacterium) granulomatis are sexually transmitted bacteria that cause characteristic, persisting ulceration on external genitals called chancroid and granuloma inguinale, respectively. Those ulcers are endemic in developing countries or exist, as does granuloma inguinale, only in some geographic "hot spots."H.

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The following series of concise summaries addresses the evolution of infectious agents in relation to sex in animals and humans from the perspective of three specific questions: (1) what have we learned about the likely origin and phylogeny, up to the establishment of the infectious agent in the genital econiche, including the relative frequency of its sexual transmission; (2) what further research is needed to provide additional knowledge on some of these evolutionary aspects; and (3) what evolutionary considerations might aid in providing novel approaches to the more practical clinical and public health issues facing us currently and in the future?

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Pertussis is a highly contagious respiratory disease that is especially dangerous for infants and children. Despite mass vaccination, reported pertussis cases have increased in the United States and other parts of the world, probably because of increased awareness, improved diagnostic means, and waning vaccine-induced immunity among adolescents and adults. Licensed vaccines do not kill the organism directly; the addition of a component inducing bactericidal antibodies would improve vaccine efficacy.

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Haemophilus ducreyi causes genital ulceration (chancroid), a sexually transmitted infection and still an important factor which contributes to the spread of HIV in developing countries. The bacterium produces a cytolethal distending toxin (HdCDT) causing cell cycle arrest and apoptosis/necrosis of human cells and contributes to the aggravation of ulcers. The aim of the study was to induce toxin-neutralizing antibodies in the genital tract of mice.

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The Haemophilus ducreyi cytolethal distending toxin (HdCDT) catalytic subunit CdtB has DNase-like activity and mediates DNA damage after its delivery into target cells. We constructed a replication-deficient adenovirus type 5 (Ad5) vector expressing CdtB and investigated the toxic properties of this vector on HeLa cells. Ad5CdtB caused loss of cell viability, morphologic changes, and cell cycle arrest, findings similar to HdCDT intoxication.

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Haemophilus ducreyi, the chancroid-causing bacterium, produces lipooligosaccharides (HdLOS) that comprise 5-11 partially sialylated monosaccharides. Subcutaneous immunisation of mice with 5 microg of HdLOS purified from H. ducreyi strains 4438 and 7470 induced high levels of anti-HdLOS IgG.

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Cytolethal distending toxin, a bacterial exotoxin produced by a number of Gram-negative species, causes growth arrest and morphological alterations in host cells. Among these species are Haemophilus ducreyi, the etiological agent of chancroid, and the periodontal pathogen Aggregatibacter actinomycetemcomitans, highly implicated in localized aggressive periodontitis. CDT induces receptor activator of NF-kappaB ligand (RANKL) expression in periodontal fibroblasts, the key bone-resorbing cytokine.

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Herpes simplex virus type 2 (HSV-2), human papillomaviruses (HPVs), and Chlamydia trachomatis are the most common pathogens causing sexually transmitted infections (STIs). There is limited information about the prevalences of these STIs in Poland. Here, we estimated the occurrence of immunoglobulin G (IgG) antibodies against HSV-2, HPV, and C.

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The aim of this study was to estimate: the frequency of aerobic vaginitis, susceptibility of the GBS isolated from vagina of non-pregnant women with and without cervicitis to selected antibiotics and chemotherapeutics and the proinflammatory cytokines production by HeLa, THP-I, U - 937 cells after stimulation by vaginal GBS. Our results indicated low frequency of the aerobic vaginitis -4.5% among non-pregnant young women and ability of the vaginal GBS to release proinflammatory cytokines by human cell lines in vitro.

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Haemophilus ducreyi cytolethal distending toxin (HdCDT) is a tripartite AB toxin, which causes DNA damage in affected cells. We investigated the effects of formaldehyde on the chemical, biological, and immunological properties of the HdCDT complex, which was purified by immobilizing the glutathione S-transferase (GST)-CdtB fusion protein, followed by binding of the CdtA and CdtC recombinant proteins. The HdCDT was treated with increasing concentrations of formaldehyde in the presence of lysine.

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The bacterium Haemophilus ducreyi causes the sexually transmitted disease chancroid, which is characterized by the appearance of mucocutaneous, persistent ulcers on the external genitals. To identify carbohydrate receptors that mediate the attachment of this pathogen to host cells, we investigated the binding of 35S-methionine-labeled H. ducreyi strains to a panel of defined glycosphingolipids that were separated on thin layer chromatography plates.

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Herpes simplex virus type 2 (HSV-2) is a common sexually transmitted infection in sub-Saharan Africa. Glycoprotein G (gG) of HSV-2 elicits a type-specific antibody response and is widely used for serodiagnosis. gG is cleaved into a secreted portion (sgG-2) and a highly O-glycosylated mature portion (mgG-2).

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Unlabelled: In an open study, 502 10-year-old children, who had received primary vaccination against diphtheria and tetanus in infancy and had varying histories of pertussis disease and vaccination, were vaccinated with diphtheria-tetanus vaccine (DT) alone or with the addition of 20 microg or 40 microg of pertussis toxoid. Diphtheria toxin neutralising antibodies, pertussis toxin IgG and tetanus toxoid IgG antibodies were measured before and 1 month after the booster. All toxoids were highly immunogenic.

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Streptococcus agalactiae, also designated group B streptococcus (GBS), is an important pathogen in neonates, pregnant women, and nonpregnant adults with predisposing conditions. We used multilocus sequence typing (MLST) to characterize 158 GBS isolates that were associated with neonatal and adult invasive disease and that were collected in northern and western Sweden from 1988 to 1997. Five major genetic lineages (sequence type [ST] 19, ST-17, ST-1, ST-23, and ST-9 complexes) were identified among the isolates, including serotype Ia, Ib, and II to V isolates, indicating a highly clonal population structure among invasive GBS isolates.

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IgG antibodies against Haemophilus influenzae type b (Hib) capsular polysaccharide (CPS) and tetanus toxoid (TT) were measured for 53 children, 10 years of age, before and 1 month after a booster dose of diphtheria-tetanus vaccine (DT). All children had been vaccinated at 3, 5 and 12 months of age with DT and a Hib-TT conjugate. Geometric mean concentrations of Hib CPS serum IgG antibody were 4.

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Haemophilus ducreyi, the etiologic agent of the sexually transmitted disease chancroid, produces a cytolethal distending toxin (HdCDT) that inhibits cultured cell proliferation, leading to cell death. A rabbit model of dermal infection was used to investigate the roles of H. ducreyi bacteria and HdCDT in the development, clinical appearance, and persistence of infection.

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We investigated the impact of highly purified Haemophilus ducreyi cytolethal distending toxin (HdCDT) on the apoptosis and necrosis of various human cells; including myeloid cells, epithelial cells, keratinocytes, and primary fibroblasts. The levels of apoptosis and necrosis induced in these cells were compared to those induced by HdCDT in human T cells and in the Jurkat T cell line. Levels of caspase-3 activity were measured, and membrane changes like phosphatidylserine (PS) translocation was evaluated after double-staining with the fluorescein isothiocyanate (FITC)-labeled annexin V and propidium iodide (PI) using flow cytometry.

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The effect of pertussis toxoid on the immunogenicity of diphtheria and tetanus toxoids (DT) was studied during a double blind efficacy trial of an acellular pertussis vaccine. Infants received DT with or without pertussis toxoid at 3, 5 and 12 months of age. Geometric mean concentrations were higher in the DT than in the DT-pertussis toxoid group 1 month (diphtheria toxoid 4.

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To evaluate the early stages of the host response to chancroid bacterium Haemophilus ducreyi, we investigated the in vitro responses of monocyte-derived dendritic cells (DCs) and macrophages (MQs) to this pathogen and Haemophilus influenzae. The phagocytic activities and pro-inflammatory cytokine secretion profiles of the antigen-presenting cells (APCs) were analyzed after exposure to gentamycin-killed bacteria, H. ducreyi lipooligosaccharide (LOS), and purified cytolethal distending toxin (HdCDT).

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Antibodies specific for the cytolethal-distending toxin of Haemophilus ducreyi (HdCDT) complex and for the CdtA, CdtB, and CdtC components were measured by ELISA in the sera of 50 patients with culture and/or PCR proven chancroid, 42 patients with periodontitis, 50 blood donors from Tanzania, 50 blood donors from Sweden. In addition, the biological activity e.g.

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Background: The etiological agent is usually not established in cases of genital ulcer disease (GUD) in Tanzania, since diagnosis and treatment of this disease are based mainly on clinical rather than microbiologic parameters. GUD increases the risk of infection with HIV. However, the association between specific GUD infections and HIV infection has not been fully investigated.

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The cytolethal distending toxin of Haemophilus ducreyi (HdCDT) is a three-component toxin that induces the arrest of the mammalian cell cycle in the G2 phase. All of the individual gene products, CdtA, CdtB and CdtC, are required for toxic activity on cultured mammalian cells. The CdtB component alone exerts nuclease activity.

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Haemophilus ducreyi, the etiologic agent of the sexually transmitted disease chancroid, produces a cytolethal distending toxin (HdCDT) that inhibits mammalian cell proliferation. We investigated the effects of HdCDT on normal human endothelial cells and on tubule formation in an in vitro model of angiogenesis. Endothelial cells were arrested in the G2 phase of the cell cycle, and tubule formation was inhibited in a dose-dependent manner.

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We investigated the phagocytosis of Haemophilus ducreyi both in vitro and in vivo. Human granulocyte and monocyte phagocytosis of opsonized and nonopsonized, fluorescence-labeled H. ducreyi was assessed by flow cytometry.

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