The effect of UVB radiation on skin microbiota in patients with atopic dermatitis and healthy controls.

Objectives: To investigate Staphylococcus aureus and Staphylococcus epidermidis quantitatively in adult patients with atopic dermatitis and in healthy controls treated with UVB radiation.

Study Design: Twenty-three adult patients (of these, 3 were excluded) with flexural atopic dermatitis and 20 healthy controls were randomly selected at the outpatient clinic of the Dermatological Department, University Hospital, North Norway.

Methods: Adult patients with atopic dermatitis (n = 20) and healthy controls (n = 20) were given 20 UVB treatments.

No detectable Chlamydia pneumoniae and cytomegalovirus DNA in leukocytes in subjects with echolucent and echogenic carotid artery plaques.

Background: Controversy exists whether persistent Chlamydia pneumoniae or cytomegalovirus infections cause initiation or progression of atherosclerosis. C. pneumoniae DNA in peripheral blood mononuclear cells (PBMC) has been proposed to be a more reliable marker of cardiovascular risk than are C.

Staphylococcus aureus small colony variants are resistant to the antimicrobial peptide lactoferricin B.

Objectives: To determine whether Staphylococcus aureus small colony variants (SCVs) are resistant to the antimicrobial peptide lactoferricin B. To assess if deficiency in transmembrane potential, a common characteristic of SCVs that are haemin- or menadione-auxotrophs, affects the uptake of the peptide into the bacterial cytoplasm.

Methods: A broth microdilution technique was used for susceptibility testing to determine the MIC of lactoferricin B for SCVs with three different auxotrophisms (haemin, menadione or thymidine) and their isogenic parent strains.

Induced resistance to the antimicrobial peptide lactoferricin B in Staphylococcus aureus.

This study was designed to investigate inducible intrinsic resistance against lactoferricin B in Staphylococcus aureus. Serial passage of seven S. aureus strains in medium with increasing concentrations of peptide resulted in an induced resistance at various levels in all strains.

Lactoferricin B inhibits bacterial macromolecular synthesis in Escherichia coli and Bacillus subtilis.

Most antimicrobial peptides have an amphipathic, cationic structure, and an effect on the cytoplasmic membrane of susceptible bacteria has been postulated as the main mode of action. Other mechanisms have been reported, including inhibition of cellular functions by binding to DNA, RNA and proteins, and the inhibition of DNA and/or protein synthesis. Lactoferricin B (Lfcin B), a cationic peptide derived from bovine lactoferrin, exerts slow inhibitory and bactericidal activity and does not lyse susceptible bacteria, indicating a possible intracellular target.

Anti-complement effects of lactoferrin-derived peptides.

Lactoferrin is an important biological molecule with many functions such as modulation of the inflammatory response, iron metabolism and antimicrobial defense. One effect of lactoferrin is the inhibition of the classical complement pathway. This study reports that antimicrobial peptides derived from the N-terminal region from both human and bovine lactoferrin, lactoferricin H and lactoferricin B, respectively, inhibit the classical complement pathway.

Evidence for a direct antitumor mechanism of action of bovine lactoferricin.

Background: Bovine lactoferrin (LFB) and its pepsin-generated peptide lactoferricin (LfcinB) possess antitumor activities. The mechanism underlying the antitumor activities of LfcinB in vivo has not been elucidated. In this study the antitumor activities exerted by LFB, LfcinB and murine lactoferricin (LfcinM) on murine tumor cell lines and experimental tumors were investigated.

Proteases in Escherichia coli and Staphylococcus aureus confer reduced susceptibility to lactoferricin B.

Lactoferricin B is a cationic antimicrobial peptide derived from the N-terminal part of bovine lactoferrin. The effect of bacterial proteases on the antibacterial activity of lactoferricin B towards Escherichia coli and Staphylococcus aureus was investigated using various protease inhibitors and protease-deficient E. coli mutants.

Chlamydia pneumoniae IgA- and IgG antibodies in young survivors of myocardial infarction. A comparison of antibody detection by a microimmunofluorescence test and an enzyme immunoassay.

Objectives: Chronic Chlamydia pneumoniae infection is considered as a cardiovascular risk factor and antibodies are commonly analysed by the subjective microimmunofluorescence (MIF) test. We wanted to investigate the C. pneumoniae IgA- and IgG seroprevalence in young survivors of myocardial infarction and matched controls, and to compare the agreement of detecting antibodies between a MIF test and an enzyme immunoassay (EIA).

[Natural antimicrobial peptides--promising new antibiotics or a problem later on?].

Background: Antimicrobial proteins and peptides are important elements of host defence that are found in virtually all living species examined so far.

Material And Methods: This review is based on the author's own research and a search of Medline (key words: antimicrobial peptides, biochemistry, mode of action, resistance).

Results: In animals, antimicrobial peptides are found on mucosal epithelial surfaces, in body fluids and in the microbicidal organelles of phagocytic cells.

The prevalence of antibiotic resistance in bacterial respiratory pathogens from Norway is low.

Objectives: To determine the degree of bacterial susceptibility to the most commonly used drugs for respiratory infections in Norway, and to find if bacterial resistance is emerging.

Methods: Clinical isolates of Streptococcus pneumoniae, Haemophilus influenzae and group A streptococci from respiratory tract specimens and from the eye were collected from different parts of Norway during two study periods. During the first period (1993-1994), three laboratories, covering 15% of the Norwegian population, participated.

[What makes bacteria pathogenic?].

Pathogenicity represents a form of specialization that enables certain microorganisms to replicate within specific animals and damage host cells. The outcome is as dependent on the host as it is upon the properties of the pathogen. The ability of the human body to prevent most of the bacteria it encounters from doing harm is the result of an evolutionary course that has produced a complex set of overlapping defenses.

The antimicrobial peptides lactoferricin B and magainin 2 cross over the bacterial cytoplasmic membrane and reside in the cytoplasm.

The localization of immunolabelled antimicrobial peptides was studied using transmission electron microscopy. Staphylococcus aureus and Escherichia coli were exposed to lactoferricin B (17-41), lactoferricin B (17-31) and D-lactoferricin B (17-31). E.

Remarkable attachment of lactoferrin to Streptococcus pyogenes during acute pharyngotonsillitis.

The purpose of this study was to establish whether lactoferrin (hLf) attached to Streptococcus pyogenes, one causative agent of acute pharyngotonsillitis (AT), during the course of the disease. Bacterial samples were obtained from the tonsillar surfaces of 7 patients (6 females, 1 male; median age 26 years; range 16-50 years) suffering from AT who were culture-positive for S. pyogenes and from 5 healthy adult controls who were culture-negative for this pathogen.

Post-antibiotic effect of the antimicrobial peptide lactoferricin on Escherichia coli and Staphylococcus aureus.

Lactoferricin is an antimicrobial peptide generated by gastric pepsin cleavage of lactoferrin. A possible post-antibiotic effect (PAE) of bovine lactoferricin (Lfcin B) and two shorter peptide derivatives against Staphylococcus aureus and Escherichia coli was studied. A drug removal technique involving centrifugation and washing was used.

Laboratory diagnosis of respiratory diseases: PCR versus serology.

We present a comparison between serology and genetic detection of three bacterial pathogens causing lower respiratory tract infection (LRI). We evaluated serology and PCR for the detection of Mycoplasma pneumoniae, Bordetella pertussis and Chlamydia pneumoniae from 1712 nasopharyngeal and serum samples. For 856 nasopharyngeal samples, average PCR time was 7.

Bactericidal kinetics of 3 lactoferricins against Staphylococcus aureus and Escherichia coli.

Bovine lactoferricin is an antimicrobial, cationic peptide generated upon gastric pepsin cleavage of bovine lactoferrin. We investigated the bactericidal effects of native lactoferricin [Lfcin B(17-41)], a shortened derivative [Lfcin B(17-31)] and the all-D-amino acid counterpart of Lfcin B(17-31) against Escherichia coli and Staphylococcus aureus. The results revealed different activities for the peptides against Gram-positive and -negative bacteria.

Lactoferrin and cyclic lactoferricin inhibit the entry of human cytomegalovirus into human fibroblasts.

Lactoferrin is mainly produced by polymorphonuclear leukocytes and has been demonstrated in mammalian milk and external secretions. Lactoferrin is an iron-binding, multifunctional protein and may play an important role in immune regulation and in defense mechanisms against bacteria, fungi and viruses. Lactoferricin is a potent antimicrobial peptide generated from the N-terminal part of lactoferrin by pepsin cleavage.

Lactoferricin B causes depolarization of the cytoplasmic membrane of Escherichia coli ATCC 25922 and fusion of negatively charged liposomes.

Antimicrobial peptides have been extensively studied in order to elucidate their mode of action. Most of these peptides have been shown to exert a bactericidal effect on the cytoplasmic membrane of bacteria. Lactoferricin is an antimicrobial peptide with a net positive charge and an amphipatic structure.

[Guidelines for diagnosis and treatment of sore throat].

Background: Available guidelines for the diagnosis and treatment of sore throat give conflicting recommendations. Our aim was to develop evidence-based guidelines.

Material And Methods: We searched The Cochrane Library, Medline and other sources for systematic reviews and other evidence that met explicit inclusion criteria for all of the relevant options and outcomes we identified.

[Guidelines for diagnosis and treatment of sore throat].

Background: Available guidelines for the diagnosis and treatment of sore throat give conflicting recommendations. Our aim was to develop evidence-based guidelines.

Material And Methods: We searched The Cochrane Library, Medline and other sources for systematic reviews and other evidence that met explicit inclusion criteria for all of the relevant options and outcomes we identified.

[Guidelines for diagnosis and treatment of acute urinary tract problems in women].

Background: Available guidelines for the management of symptoms of lower urinary tract infections (UTI) in women give conflicting recommendations.

Material And Methods: We searched The Cochrane Library, Medline and other sources for evidence that met explicit inclusion criteria for the relevant options and outcomes identified. The validity of included studies was assessed.