Species distribution and susceptibility to azoles of vaginal yeasts isolated prostitutes.

Objective: We investigated the use of miconazole among female prostitutes in Costa Rica as well as the distribution of vaginal yeasts and the susceptibility pattern to azoles of strains obtained from this population. Our intention was to relate a frequent use of miconazole to occurrence of vaginal yeasts resistant to azoles.

Methods: Vaginal samples were taken from 277 patients that have previously used azoles.

Aggregates of ultrafine particles modulate lipid peroxidation and bacterial killing by alveolar macrophages.

We hypothesized that aggregates of ultrafine carbon and washed diesel particles impair the ability of alveolar macrophages (AM) to kill bacteria and enhance the AM lipid peroxidation (LPO) of lung surfactant. Rat AM were exposed, 5h, to particles 20 microg/ml. The AM, containing carbon or washed diesel particles, were incubated 2h, with Streptococcus pneumoniae, an American Type Culture Collection (ATCC) strain or clinical isolates.

Characterization of beta-lactam-resistant Bacteroides fragilis isolates by use of PCR fingerprinting.

PCR fingerprinting was used for characterization of 35 beta-lactam-resistant Bacteroides fragilis strains isolated in Sweden and Hungary. Ten B. fragilis strains showed unique PCR fingerprints by use of the M13 core primer.

Aggregates of ultrafine particles impair phagocytosis of microorganisms by human alveolar macrophages.

We investigated whether exposure of alveolar macrophages to aggregates of ultrafine carbon particles affected subsequent phagocytosis of microorganisms. Human alveolar macrophages were obtained by bronchoalveolar lavage and exposed to aggregates of ultrafine carbon particles or diesel exhaust particles (DEP) for 20 h before measurements of phagocytosis. The particle loads were estimated to be comparable to those of air pollution exposure with established health effects in humans.

Spontaneous breathing or mechanical ventilation alters lung compliance and tissue association of exogenous surfactant in preterm newborn rabbits.

In preterm infants with respiratory distress syndrome, surfactant administration followed by immediate extubation to spontaneous breathing with nasal continuous positive airway pressure reduces the need for mechanical ventilation. With this treatment approach, repeated doses of surfactant are rarely indicated. We used a rabbit model to test the hypothesis that exogenous surfactant therapy followed by spontaneous breathing results in a more sustained initial treatment response compared with treatment followed by mechanical ventilation.

Influence of modified natural and synthetic surfactant preparations on bacterial killing by polymorphonuclear leucocytes.

In addition to its biophysical functions, surfactant plays an important role in pulmonary host defense. In this investigation we studied the influence of various commercially available surfactants on the phagocytosis of bacteria that are common pathogens in the neonatal period. Group B streptococci (GBS), Escherichia coli and Staphylococcus aureus were cultured with isolated human polymorphonuclear leucocytes (PMN) and non-specific serum in the presence or absence of different modified natural (Curosurf, Alveofact, Survanta) or totally synthetic, protein-free surfactant preparations (Exosurf, Pumactant).

Lipid peroxidation of lung surfactant in experimental neonatal group B streptococcal pneumonia.

Group B streptococcal (GBS) pneumonia, with neutrophilic granulocytes immigrating into the lungs, may occur in neonates. The incidence is particularly high among preterm infants, who often are treated with exogenous surfactant. We have previously demonstrated in vitro that neutrophils stimulated by GBS cause lipid peroxidation (LPO) and functional impairment of lung surfactant.

Lipid peroxidation of lung surfactant due to reactive oxygen species released from phagocytes stimulated by bacteria from children with cystic fibrosis.

We used Pseudomonas aeruginosa, Burkholderia cepacia and Stenotrophomonas maltophilia, live or heat-killed, isolated from the airways of children with Cystic Fibrosis, to stimulate human neutrophils (PMN) and rat alveolar macrophages (AM) to produce reactive oxygen metabolites in the presence or absence of Curosurf, a natural porcine lung surfactant. We determined: (1) the amount of lipid peroxidation (LPO) as assessed by the amounts of malondialdehyde (MDA) and 4-hydroxyalkenals (4-HNE) using the LPO 586 test kit; (2) the production by AM of superoxide with the nitroblue tetrazolium test and (3) of nitric oxide (NO) with the Griess reaction. Stimulation of PMN or AM increases LPO of Curosurf and cell wall lipids.

Influence of partial liquid ventilation on bacterial growth and alveolar expansion in newborn rabbits with group B-streptococcal pneumonia.

Partial liquid ventilation (PLV) with perfluorocarbons has been considered as an alternative therapy for severe inflammatory lung disease. The present study was performed to test whether PLV influences bacterial growth and lung histology in a rabbit model of congenital pneumonia caused by group B streptococci. Near-term newborn rabbits were tracheotomized, inoculated via the airways with group B streptococci, and subsequently ventilated for 5 h with either PLV or conventional ventilation.

Effects of antioxidants on surfactant peroxidation by stimulated human polymorphonuclear leukocytes.

Production of oxygen radicals by stimulated phagocytes followed by surfactant lipid peroxidation (LPO) and loss of surfactant function have all been implicated in the pathogenesis of acute lung injury. We studied the interactions between natural lung surfactant (Curosurf) and neutrophils in vitro, and compared various antioxidants; (superoxide dismutase (SOD), vitamin E, vitamin C, ebselen and melatonin), or combinations of them in duplicate and triplicate regarding their ability to decrease superoxide production and the peroxidation level of surfactant caused by activated phagocytes. The superoxide production of neutrophils activated by Candida albicans was measured with the nitroblue tetrazolium (NBT) test.

Experimental and calculated parameters on particle phagocytosis by alveolar macrophages.

Phagocytosis of three types of fluorescein-labeled test particles by rat alveolar macrophages (AM) were studied: spherical silica (3.2 microm), heat-killed Candida albicans (3.8 microm), and heat-killed Cryptococcus neoformans (6.

Lipid peroxidation caused by oxygen radicals from Fusobacterium-stimulated neutrophils as a possible model for the emergence of periodontitis.

Objective: The possible contribution of bacteria and polymorphonuclear neutrophils (PMN) to the disease process of periodontitis was evaluated.

Design: Fusobacterium nucleatum has been associated with chronic adult periodontitis. Intracellular production and extracellular release of reactive oxygen species (ROS) by PMN stimulated by fusobacteria were evaluated.

Antibodies against a truncated Staphylococcus aureus fibronectin-binding protein protect against dissemination of infection in the rat.

Staphylococcus aureus bacteraemia (SAB) originating from local infections can lead to severe secondary infections such as endocarditis. The protective effect of antibodies against secondary infections was studied in a rat model, where a local joint infection leads to bacteraemia and endocarditis on damaged aortic valves. In this study, immunizations with a truncated D2-domain of the S.

Effect of surfactant and specific antibody on bacterial proliferation and lung function in experimental pneumococcal pneumonia.

Objective: To investigate the effect of surfactant and specific antibody on bacterial proliferation in experimental pneumococcal pneumonia.

Methods: Near-term newborn rabbits received a standard dose (10(7)) of type 3 pneumococci via the airways. Control animals were sacrificed 1 minute later.

Lipid peroxidation by alveolar macrophages challenged with Cryptococcus neoformans, Candida albicans or Aspergillus fumigatus.

Increased formation of oxygen radicals has previously been shown for alveolar macrophages (AM) challenged with Cryptococcus neoformans cells opsonized with fresh serum or polyclonal immunoglobulin G. AM show similar responses to Candida albicans or Aspergillus fumigatus. Oxygen radicals are capable of damaging various macromolecules, including lipids.

Direct and phagocyte-mediated lipid peroxidation of lung surfactant by group B streptococci.

In newborn infants, group B streptococci (GBS) often cause pneumonia, with polymorphonuclear leukocytes (PMN) migrating into the lungs. Because surfactant therapy may be needed in such patients, we evaluated the interaction between GBS or GBS-stimulated PMN and a surfactant preparation (Curosurf) in vitro. The superoxide production of GBS strains or GBS-activated PMN was measured, using the nitroblue tetrazolium (NBT) test and the subsequent lipid peroxidation (LPO) as the content of malondialdehyde (MDA) and 4-hydroxyalkenals (4-HNE).

Cytokine, elastase and oxygen radical release by Fusobacterium nucleatum-activated leukocytes: a possible pathogenic factor in periodontitis.

Periodontitis is characterised by tissue destruction caused by reactive oxygen species (ROS) and proteolytic enzymes, which are released by the interaction between bacteria and phagocytes. We estimated the ability of Fusobacterium species to induce release of tissue destructive and proinflammatory mediators from in vitro activated peripheral leukocytes. ROS was measured with the nitroblue tetrazolium (NBT) method, elastase with a specific chromogenic substrate and cytokines, including interleukin 1beta (IL-1beta), tumour necrosis factor alpha (TNF-alpha), and interleukin 8 (IL-8) with a sandwich ELISA method.

Treatment of experimental Cryptococcus neoformans infection in newborn rabbits by airway instillation of specific antibody and surfactant.

Cryptococcosis in AIDS patients has a slow response to antifungal chemotherapy, and passive antibody treatment has thus been considered as an adjunct. Polyclonal anticryptococcal IgG dissolved in a suspension of modified natural surfactant was given intratracheally to near-term rabbits. Killing of Cryptococcus neoformans within the lungs was determined by counting the colony forming units (cfu).

Interaction between lung surfactant and nitric oxide production by alveolar macrophages stimulated by group B streptococci.

The major etiologic agent in neonatal pneumonia and meningitis is group B streptococci (GBS). Nitric oxide (NO) production by alveolar macrophages (AM) in response to Gram-positive bacteria such as GBS and the effect of surfactant on this production have received little attention. We studied production of NO by GBS-stimulated AM using the Griess reaction, the effect of lung surfactant on this NO production, and the possible lipid peroxidation (LPO) of surfactant caused by NO.

Mercury intolerance in relation to superoxide dismutase, glutathione peroxidase, catalase, and the nitroblue tetrazolium responses.

Through percutaneous provocation with metallic mercury and phenyl mercuric acetate in patients stating the presence of subjective psychosomatic symptoms following dental amalgam treatment, it has been possible to categorize and score two extreme groups of patients, mercury-intolerant and mercury-tolerant patients reacting and not reacting, respectively, to low doses of mercury. The intolerant patients had a high psychosomatic score and the tolerant patients had a low or null score when exposed to low doses of the two mercury compounds. Determination of the scavenger enzymes superoxide dismutase, glutathione peroxidase, and catalase showed no significant differences between the mercury-intolerant and the mercury-tolerant patients and the controls.

In vitro effect of lung surfactant on alveolar macrophage defence mechanisms against Cryptococcus neoformans.

The effects of a modified natural porcine surfactant (Curosurf) on phagocytosis and killing of Cryptococcus neoformans by alveolar macrophages and on the production of superoxide anions were investigated in vitro. Attachment and ingestion were evaluated separately by a fluorescent quenching technique. The nitroblue tetrazolium reduction test was used as an indirect measurement of superoxide anion production.

Production of nitric oxide by rat alveolar macrophages stimulated by Cryptococcus neoformans or Aspergillus fumigatus.

Cryptococcus neoformans and Aspergillus fumigatus are airborne fungi and the alveolar macrophages (AM) constitute a first line of host defence against both pathogens. We investigated the ability of rat AM to produce nitric oxide (NO) when challenged in vitro with C. neoformans, A.

Phagocyte-induced lipid peroxidation of different intravenous fat emulsions and counteractive effect of vitamin E.

Unsaturated fatty acids, a major component of fat emulsions used in parenteral nutrition, are prone to peroxidation which is an important feature of oxygen-associated tissue damage. We used the nitroblue tetrazolium (NBT) reduction test to measure the production of superoxide radicals by stimulated polymorphonuclear neutrophils (PMN) in the presence of different fat emulsions: Intralipid (containing 100% long-chain triacylglycerols, LCT), Vasolipid (a physical mixture of 50% LCT and 50% medium-chain triacylglycerols, MCT) and Structolipid (structured triacylglycerols containing 63% LCT and 37% MCT). We measured the amount of malonaldehyde (MDA) and 4-hydroxyalkenal to determine the lipid peroxidation of the three fat emulsions in the presence of stimulated neutrophils.

Combined treatment with surfactant and specific immunoglobulin reduces bacterial proliferation in experimental neonatal group B streptococcal pneumonia.

Neonates suffering from group B streptococcal (GBS) pneumonia often lack type-specific opsonizing antibodies. We studied the influence of combined intratracheal treatment with surfactant and a specific antibacterial polyclonal antibody (IgG fraction) on bacterial proliferation and lung function in an animal model of GBS pneumonia. Near-term newborn rabbits received an intratracheal injection of either the specific IgG antibody, nonspecific IgG, surfactant, a mixture of surfactant and the antibody, or 0.

Phagocyte-induced lipid peroxidation of lung surfactant.

Surfactant therapy is given routinely to premature newborns with respiratory failure. However, alterations in surfactants have been shown to be a significant factor in some forms of respiratory failure in newborns in animal models of lung injury. To investigate whether antioxidant supplementation might help to protect exogenous surfactant from damage by oxygen free radicals, we examined the influence of vitamin E in combination with surfactant on superoxide production as estimated by the nitroblue tetrazolium reduction test, and measured surfactant peroxidation with a new colorimetric method with or without addition of superoxide dismutase (SOD) or vitamin E.