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1.
Rheuma Plus ; 19(4): 144-151, 2020.
Article in German | MEDLINE | ID: mdl-32837592

ABSTRACT

The SARS-CoV­2 has infected millions of humans worldwide in the past few months and hundreds of thousands have died as a result of an infection. The end of the pandemic is not in sight and many people are anxious of becoming infected in different settings. The Gastein Healing Gallery (GHG) is a unique outpatient facility combining heat, high humidity and mild radon radiation. Every year approximately 12,000 patients with inflammatory rheumatic, degenerative diseases and chronic pain are treated. We have therefore reviewed and analyzed the literature with respect to a possible increased risk of infection for patients during treatment in the GHG. On the one hand the climatic and physical conditions in the GHG can be viewed as hostile to viruses and on the other hand the mild radon hyperthermia and the geographic location of the GHG lead to positive effects on the patient's health via complex physiological processes. We therefore consider the likelihood of infection with viruses in the GHG in no way increased, in contrast, it is probably considerably lower compared to other settings.

2.
S Afr Med J ; 102(6): 525-7, 2012 May 23.
Article in English | MEDLINE | ID: mdl-22668955

ABSTRACT

BACKGROUND: Invasive meningococcal disease (MD), caused by Neisseria meningitidis infection, is endemic in South Africa, with a seasonal peak in winter and spring. There were 2 432 laboratory-confirmed cases between 2006 and 2010. Human deficiency of the fifth complement component (C5D) or complete absence of the sixth component (C6Q0) leads to increased risk of MD, which is often recurrent. All attacks are serious and can lead to death or severe long-term consequences. OBJECTIVE: To determine the frequency of specific disease-associated C5 and C6 gene mutations in patients presenting with MD in the Western Cape. RESULTS: In 109 patients with confirmed invasive MD investigated for local mutations known to cause C5D and C6Q0, 3 were C5D and 11 were C6Q0. In 46 black patients tested, 3 were C5D and 7 were C6Q0. In 63 coloured patients, none were C5D and 4 were C6Q0. All deficient patients were followed up and offered prophylaxis. CONCLUSION: C5D and C6Q0 are not rare genetic diseases in South Africa and affected patients are susceptible to repeated MD; 12.8% of MD patients tested were C5D or C6Q0. Blacks were at greatest risk with 21.7% being either C5D or C6Q0. We strongly recommend diagnostic testing for complement C5 and C6 deficiency in the routine work-up of all MD cases in South Africa. Prophylactic treatment should be started in susceptible individuals.


Subject(s)
Black People/genetics , Complement C5/genetics , Complement C6/genetics , Meningitis, Meningococcal/genetics , Complement C5/metabolism , Genetic Predisposition to Disease , Genetic Testing , Humans , Infant , Infant, Newborn , Meningitis, Meningococcal/ethnology , Mutation , Sequence Analysis, DNA , South Africa
3.
Int J Immunogenet ; 38(5): 383-7, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21649859

ABSTRACT

Typical haemolytic uraemic syndrome (HUS) is mainly caused by infections with enterohaemorrhagic Escherichia coli, whereas in atypical, nonbacteria-associated HUS, complement plays a dominant role. Recently, complement has also been shown to be involved in typical HUS. In this study, mostly weakly significant associations with homozygosities of complement allotype C7 M and inversely with factor H 402H were found, suggesting that 402Y and C7 M allotypes predispose to (typical) haemolytic uraemic syndrome.


Subject(s)
Escherichia coli Infections/genetics , Hemolytic-Uremic Syndrome/genetics , Mutation , Complement Factor H/genetics , Complement Factor H/immunology , Complement System Proteins/genetics , Escherichia coli Infections/immunology , Escherichia coli Infections/pathology , Hemolytic-Uremic Syndrome/immunology , Hemolytic-Uremic Syndrome/microbiology , Humans
5.
Infection ; 36(4): 362-7, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18574554

ABSTRACT

BACKGROUND: The present study was aimed to searching for CTX-M-type extended-spectrum beta-lactamases in community- and hospital-acquired Escherichia coli (E. coli) collected in western Austria and to investigate their clonal relatedness and their ability to spread. PATIENTS AND METHODS: All patients with E. coli positive cultures collected from a catchment population of 186,000 between January and July 2006 were enrolled into the study. CTX-M-producing E. coli were identified by antibiotic susceptibility testing and blaCTX-M multiplex PCR. Clonal relatedness was analyzed by pulsed-field gel electrophoresis (PFGE). RESULTS: In 2,042 E. coli isolates, 20 isolates (16 from urine, 4 from blood cultures) demonstrated CTX-M-1-related genes and no CTX-M-2- or CTX-M-9-related enzymes or CTX-M-15-producing strains were identified. We did not find clonal relatedness among CTX-M-1 producers isolated from the same referring center. E. coli were investigated for plasmid transfer ability of CTX-M-1-encoding genes. Plasmid digest patterns were not consistent with episomal spread of resistance loci. Transfection of CTX-M-encoding plasmids failed. CONCLUSION: Our data suggest that the emergence of CTX-M-1-producing E. coli in western Austria may be attributed to multiple independent events.


Subject(s)
Escherichia coli Infections/microbiology , Escherichia coli/enzymology , beta-Lactamases/biosynthesis , Adult , Aged , Aged, 80 and over , Anti-Infective Agents/pharmacology , Austria , Bacteremia/microbiology , Bacterial Typing Techniques , Cluster Analysis , Community-Acquired Infections/microbiology , Cross Infection/microbiology , Drug Resistance, Bacterial/genetics , Escherichia coli/drug effects , Escherichia coli/genetics , Escherichia coli/isolation & purification , Female , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Plasmids/genetics , Urinary Tract Infections/microbiology , beta-Lactamases/genetics
6.
Mol Immunol ; 45(5): 1485-93, 2008 Mar.
Article in English | MEDLINE | ID: mdl-17915330

ABSTRACT

Pathogenic fungi represent a major threat particularly to immunocompromised hosts, leading to severe, and often lethal, systemic opportunistic infections. Although the impaired immune status of the host is clearly the most important factor leading to disease, virulence factors of the fungus also play a role. Factor H (FH) and its splice product FHL-1 represent the major fluid phase inhibitors of the alternative pathway of complement, whereas C4b-binding protein (C4bp) is the main fluid phase inhibitor of the classical and lectin pathways. Both proteins can bind to the surface of various human pathogens conveying resistance to complement destruction and thus contribute to their pathogenic potential. We have recently shown that Candida albicans evades complement by binding both Factor H and C4bp. Here we show that moulds such as Aspergillus spp. bind Factor H, the splicing variant FHL-1 and also C4bp. Immunofluorescence and flow cytometry studies show that the binding of Factor H and C4bp to Aspergillus spp. appears to be even stronger than to Candida spp. and that different, albeit possibly nearby, binding moieties mediate this surface attachment.


Subject(s)
Complement C4b-Binding Protein/metabolism , Complement Factor H/metabolism , Complement Inactivator Proteins/physiology , Immunity , Aspergillus/immunology , Complement C3b Inactivator Proteins , Humans , Protein Binding
7.
Eur J Clin Microbiol Infect Dis ; 26(2): 141-5, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17216421

ABSTRACT

In a case-control study that included a total of 98 patients and 83 controls, the possible link between various pathogens and abdominal aortic aneurysms was investigated. For 68 patients with abdominal aortic aneurysm and age-matched controls, no differences were detected in the levels of immunoglobulin (Ig)A and IgG Chlamydiaceae and Chlamydophila pneumoniae antibodies. Patients with IgA titers positive for Chlamydophila pneumoniae showed progressive disease (defined as an annual increase of the aneurysm diameter of > or = 0.5 cm) more frequently than patients with negative IgA titers (p = 0.046). Polymerase chain reactions performed to detect DNA for Chlamydophila pneumoniae, Chlamydia trachomatis, Chlamydophila psittaci, human cytomegalovirus, Borrelia burgdorferi and Helicobacter pylori in tissue specimens of 30 patients and 15 controls were negative. In summary, Chlamydophila pneumoniae may contribute to aortic aneurysm disease progression, but DNA of this and other pathogens was not found in patients' specimens.


Subject(s)
Antibodies, Bacterial/blood , Aorta, Abdominal/microbiology , Aortic Aneurysm, Abdominal/microbiology , Chlamydiaceae/immunology , Chlamydophila pneumoniae/immunology , DNA, Bacterial/analysis , Aged , Aged, 80 and over , Case-Control Studies , Chlamydia Infections/immunology , Chlamydia Infections/microbiology , Chlamydiaceae/genetics , Chlamydiaceae/isolation & purification , Chlamydiaceae Infections/immunology , Chlamydiaceae Infections/microbiology , Chlamydophila pneumoniae/genetics , Chlamydophila pneumoniae/isolation & purification , Female , Humans , Immunoglobulin A/blood , Immunoglobulin G/blood , Male
8.
Epidemiol Infect ; 134(4): 719-23, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16371175

ABSTRACT

This study investigates a sorbitol-fermenting enterohaemorrhagic Escherichia coli (SF EHEC) O157 infection in a farmer's family in the Austrian province of Salzburg. The investigation commenced after a 10-month-old boy was admitted to hospital with the clinical diagnosis of a haemolytic-uraemic syndrome (HUS) and his stool specimen grew SF EHEC O157:H-. In a subsequent environmental survey, a stool specimen of the 2-year-old brother and faecal samples of two cattle from the family's farm were also found to be positive for SF EHEC O157:H-. All four isolates had indistinguishable phenotypic and molecular characteristics and were identical to the first strain detected in Bavaria in 1988. Despite identical isolates being demonstrated in Bavaria after 1988, and until this report, increased surveillance in neighbouring Austria had not found this organism. We propose that the strain may have recently spread from Bavaria to Austria. Although SF EHEC O157:H- strains are still rare, they may represent a considerable health threat as they can spread from farm animals to humans and between humans.


Subject(s)
Bacterial Toxins/genetics , Escherichia coli O157/isolation & purification , Escherichia coli Proteins/genetics , Hemolytic-Uremic Syndrome/microbiology , Shiga Toxins/genetics , Animals , Austria , Cattle , Child , Escherichia coli Infections/epidemiology , Escherichia coli Infections/microbiology , Escherichia coli Infections/transmission , Escherichia coli Proteins/metabolism , Feces/microbiology , Fermentation , Hemolytic-Uremic Syndrome/epidemiology , Hemolytic-Uremic Syndrome/genetics , Humans , Male , Risk Factors , Shigella/genetics , Sorbitol/metabolism , Surveys and Questionnaires , Virulence/genetics
9.
Arch Virol ; 150(10): 2077-90, 2005 Oct.
Article in English | MEDLINE | ID: mdl-15868096

ABSTRACT

Stably transfected Chinese hamster ovary (CHO24S) cells were the source for Rubella virus-like particles (RVLP) containing all structural proteins (E1, E2, C and their dimers). RVLP are secreted from the CHO24S cells into the medium and the time-point for collecting the medium with the highest yield of >100 kDa proteins (with 17 mg protein from 10 ml cell culture supernatant) was after 2 days of incubation. Different methods for RVLP isolation from the cell culture supernatants were assessed by SDS-PAGE and Western blotting (using sera positive or negative for Rubella virus (RV)-specific antibodies or an anti-E1 monoclonal antibody). A combination of membrane filtration with a rapid, novel gradient ultracentrifugation step (using Coomassie brilliant blue G crystals as adsorbens for RVLP that facilitated virus isolation) was the most suitable technique. 132 RV-positive human sera (RV IgG > 20 IU/ml by commercial ELISA) were tested by our "self made" immunoblot test stripes (using RVLP adsorbed to dye crystals as antigen) for the presence or absence of antibodies specific for RV structural proteins. 57.6% of these sera had antibodies against E1, E2 and C, 31% against E1 and C, and 1.5% against E1 only, whereas 3.8% had no RV specific antibodies and only 6.0% were equivocal which demonstrated that these "self made" test stripes can reliably differentiate RV antibody specificities.


Subject(s)
Antigens, Viral , Immunoblotting/methods , Rubella virus/immunology , Animals , Antibodies, Viral/analysis , Antibody Specificity , Antigens, Viral/genetics , CHO Cells , Coloring Agents , Cricetinae , Crystallization , Humans , Macromolecular Substances , Rubella/diagnosis , Rubella/immunology , Rubella virus/genetics , Rubella virus/isolation & purification , Transfection , Virion/immunology , Virion/isolation & purification
10.
Eur J Clin Microbiol Infect Dis ; 24(4): 268-71, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15902533

ABSTRACT

A local outbreak of Shiga toxin (Stx)-producing enterohemorrhagic Escherichia coli (EHEC) O157:H7 causing severe hemolytic-uremic syndrome (HUS) was found to be caused by environmental transmission. Automated ribotyping and pulsed-field gel electrophoresis revealed that four stx2-positive EHEC isolates obtained from two unrelated children, one mother and one cow were identical. Results of an epidemiological investigation strongly suggest that both children were infected via a meadow strewn with manure containing EHEC-positive feces from the infected cow a few days prior to the onset of illness. The cow belonged to a cattle farm neighboring the meadow. This report highlights the risk of acquiring EHEC O157 through indirect contact with a farm environment.


Subject(s)
Environmental Microbiology , Escherichia coli Infections/transmission , Escherichia coli O157/isolation & purification , Hemolytic-Uremic Syndrome/microbiology , Adult , Animals , Cattle , Child, Preschool , Deer , Disease Outbreaks , Feces/microbiology , Female , Humans , Infant , Male , Manure/microbiology , Sheep
11.
J Immunol Methods ; 296(1-2): 187-98, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15680163

ABSTRACT

Primary defence against invading microorganisms depends on a functional innate immune system and the complement system plays a major role in such immunity. Deficiencies in one of the components of the complement system can cause severe and recurrent infections, systemic diseases, such as systemic lupus erythematosus (SLE) and renal disease. Screening for complement deficiencies in the classical or alternative complement pathways has mainly been performed by haemolytic assays. Here, we describe a simple ELISA-based format for the evaluation of three pathways of complement activation. The assays are based on specific coatings for each pathway in combination with specific buffer systems. We have standardized these assays and defined cut off values to detect complement deficiencies at the different levels of the complement system. The results demonstrate the value of these ELISA-based procedures for the functional assessment of complement deficiencies in clinical practice. The assay is now available commercially in kit form.


Subject(s)
Complement Activation/immunology , Complement System Proteins/deficiency , Enzyme-Linked Immunosorbent Assay/standards , Reagent Kits, Diagnostic , Complement Pathway, Alternative , Complement Pathway, Classical , Complement Pathway, Mannose-Binding Lectin , Complement System Proteins/analysis , Complement System Proteins/immunology , Humans , Lupus Erythematosus, Systemic/diagnosis , Lupus Erythematosus, Systemic/immunology , Mannose-Binding Lectin/blood , Mannose-Binding Lectin/immunology
12.
Eur J Clin Microbiol Infect Dis ; 23(6): 502-5, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15148653

ABSTRACT

In order to ascertain the epidemiology of rubella infections in Austria, a seroepidemiological study was performed. Data collected from 115 cases diagnosed at the Institute of Hygiene and Social Medicine of the University of Innsbruck during 2001 were evaluated. The results indicate this infection can no longer be categorised as a paediatric disease (mean age, 18.5 years), and several other findings were particularly striking: (i) 47% of the patients had elevated C-reactive protein levels and 50% had increased anti-streptolysin O titres; (ii) only a few patients complained of fever, while symptoms such as rash and lymphadenopathy, which are also associated with several other viral infections, including HIV, were found frequently; and (iii) the 115 rubella cases detected in the 1-year study period represented an incidence of >13 per 100,000 population. This high incidence of infection underlines the need for further improvement of diagnostic tests and more successful vaccine strategies.


Subject(s)
Rubella Vaccine/administration & dosage , Rubella virus/isolation & purification , Rubella/epidemiology , Rubella/prevention & control , Adolescent , Adult , Age Distribution , Austria/epidemiology , Child , Child, Preschool , Cohort Studies , Female , Humans , Male , Middle Aged , Prevalence , Rubella/diagnosis , Severity of Illness Index , Sex Distribution , Vaccination/standards , Vaccination/trends
13.
Lupus ; 13(2): 139-41, 2004.
Article in English | MEDLINE | ID: mdl-14995009

ABSTRACT

We describe the case of a female patient with hereditary complete C4 deficiency and systemic lupus erythematosus. She had suffered from lupus nephritis in early childhood. At the age of 23 years she developed severe lupus with skin disease and life-threatening cerebral vasculitis. Her cerebral disease was unresponsive to high-dose steroids, intravenous immunoglobulin, fresh frozen plasma and plasma exchange. Improvement was achieved with immunoadsorption in combination with mycophenolate mofetil. The patient made a complete recovery and is maintained in complete remission on mycophenolate and low-dose steroids.


Subject(s)
Cerebrovascular Disorders/etiology , Complement C4/deficiency , Lupus Erythematosus, Systemic/complications , Mycophenolic Acid/analogs & derivatives , Vasculitis, Central Nervous System/etiology , Adult , Cerebrovascular Disorders/therapy , Female , Humans , Lupus Nephritis/complications , Mycophenolic Acid/therapeutic use , Prednisolone/therapeutic use , Vasculitis, Central Nervous System/therapy
14.
Verh Dtsch Ges Pathol ; 88: 85-8, 2004.
Article in German | MEDLINE | ID: mdl-16892537

ABSTRACT

Transplantation-associated infections are caused by an infected transplanted organ or the endogenic or exogenic environment of the recipient in a state of induced immunodeficiency. The best therapy would be to reconstitute the immunodeficiency, but this is usually impossible as it endangers the transplanted organ. Thus, a specific, standardised anti-infectious therapy is needed even in the absence of clearly identified micro-organisms [bacteria (in two thirds gram-positive rods), parasites (in central Europe predominantly Toxoplasma), fungi (especially Candida spp. or Aspergillus spp.) or viruses (such as Parvovirus B19 and Cytomegalovirus)]. Origins of infection (e.g., hygiene), types of infection (e.g., reactivation), typical localisations, diagnostic tools (e.g., blood cultures, antigenic tests, PCR, CT, advantages and disadvantages of antibody assays) and possible therapies are briefly discussed. The take home messages are to avoid economy measures in microbial diagnostics and to use CMV-seronegative donors whenever possible.


Subject(s)
Infections/etiology , Organ Transplantation/adverse effects , Transplantation Immunology , Candida albicans/isolation & purification , Communicable Disease Control , Escherichia coli/isolation & purification , Gram-Positive Bacterial Infections/etiology , Gram-Positive Bacterial Infections/pathology , Gram-Positive Bacterial Infections/prevention & control , Humans , Hygiene , Immunologic Deficiency Syndromes/complications , Immunologic Deficiency Syndromes/etiology , Immunologic Deficiency Syndromes/pathology , Infections/classification , Infections/pathology , Streptococcus/isolation & purification
15.
Eur J Clin Microbiol Infect Dis ; 22(9): 543-7, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12938008

ABSTRACT

In order to evaluate the seroprevalence of human granulocytic ehrlichiosis in western Austria, sera from 357 Tyrolean blood donors were tested by an immunofluorescence assay. To assess the concomitant seroreactivity against Borrelia burgdorferi sensu lato, sera were further investigated by enzyme-linked immunoassay and Western blot. Thirty-two sera (9.0%) showed antibodies to Anaplasma phagocytophilum at a titre of 1:128 or higher, and 30 (8.4%) were seroreactive against Borrelia burgdorferi sensu lato. Infection with these two pathogens seems to occur in all Tyrolean districts except Landeck, the most upstream district of the Inn River Valley.


Subject(s)
Ehrlichia/isolation & purification , Ehrlichiosis/diagnosis , Ehrlichiosis/epidemiology , Adult , Age Distribution , Aged , Austria/epidemiology , Blotting, Western , Borrelia burgdorferi Group/isolation & purification , Chi-Square Distribution , Ehrlichiosis/blood , Enzyme-Linked Immunosorbent Assay , Female , Humans , Incidence , Male , Middle Aged , Probability , Risk Factors , Seroepidemiologic Studies , Serologic Tests , Sex Distribution
17.
Int J Antimicrob Agents ; 21(3): 229-33, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12636983

ABSTRACT

In order to investigate the influence of different hyphal inoculum sizes on minimal inhibition concentrations (MICs) and minimum fungicidal concentrations (MFCs) of amphotericin B (AMB), voriconazole and itraconazole, five isolates each of Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger and Aspergillus terreus were studied using a broth microdilution method. Three inoculum sizes were used: 1 x 10(3)-5 x 10(3), 1 x 10(4)-5 x 10(4) and 1 x 10(5)-5 x 10(5) cfu/ml. MICs and MFCs were read at 24 and 48 h at 35 degrees C. For all species tested, AMB MICs and MFCs were minimally affected by inoculum size on. However inoculum size significantly affected MICs and MFCs of voriconazole and itraconazole; there was an increase of up to 6-fold in MICs and MFCs for the various aspergilli when the inoculum increased from 10(3) to 10(5) cfu/ml (P<0.05). Thus azoles showed significant inoculum effects, while AMB showed comparatively minimum inoculum effects against Aspergillus spp.


Subject(s)
Antifungal Agents/administration & dosage , Aspergillus/drug effects , Amphotericin B/administration & dosage , Aspergillus/growth & development , Aspergillus/isolation & purification , Aspergillus/pathogenicity , Aspergillus flavus/drug effects , Aspergillus flavus/growth & development , Aspergillus fumigatus/drug effects , Aspergillus fumigatus/growth & development , Aspergillus niger/drug effects , Aspergillus niger/growth & development , Colony Count, Microbial , Dose-Response Relationship, Drug , Drug Resistance, Fungal , Humans , In Vitro Techniques , Itraconazole/administration & dosage , Pyrimidines/administration & dosage , Triazoles/administration & dosage , Voriconazole
18.
Infect Immun ; 70(9): 5185-92, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12183569

ABSTRACT

The human facultative pathogenic yeast Candida albicans causes mucocutaneous infections and is the major cause of opportunistic fungal infections in immunocompromised patients. C. albicans activates both the alternative and classical pathway of the complement system. The aim of this study was to assay whether C. albicans binds human complement regulators in order to control complement activation at its surface. We observed binding of two central complement regulators, factor H and FHL-1, from normal human serum to C. albicans by adsorption assays, immunostaining, and fluorescence-activated cell sorter (FACS) analyses. Specificity of acquisition was further confirmed in direct binding assays with purified proteins. The surface-attached regulators maintained their complement regulatory activities and mediated factor I-dependent cleavage of C3b. Adsorption assays with recombinant deletion mutant proteins were used to identify binding domains. Two binding sites were localized. One binding domain common to both factor H and FHL-1 is located in the N-terminal short consensus repeat domains (SCRs) 6 and 7, and the other one located in C-terminal SCRs 19 and 20 is unique to factor H. These data indicate that by surface acquisition of host complement regulators, the human pathogenic yeast C. albicans is able to regulate alternative complement activation at its surface and to inactivate toxic complement activation products.


Subject(s)
Blood Proteins/metabolism , Candida albicans/immunology , Candida albicans/pathogenicity , Complement Factor H/metabolism , Binding Sites/genetics , Blood Proteins/genetics , Complement Activation , Complement C3b Inactivator Proteins , Complement Factor H/genetics , Heparin/pharmacology , Humans , In Vitro Techniques , Protein Binding , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Sequence Deletion
19.
Mycoses ; 45(5-6): 166-9, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12100533

ABSTRACT

The minimum inhibitory concentrations (MICs) of amphotericin B and lipid-based amphotericin B formulations against isolates of Aspergillus spp. were tested using a broth microdilution method. Twelve isolates of Aspergillus fumigatus, eight of Aspergillus flavus, six of Aspergillus niger and seven of Aspergillus terreus were examined. In addition, an assay for hyphae of Aspergillus spp. was performed since the invasive form is manifested by the appearance of hyphal structures. MICs of hyphae against lipid-based amphotericin B formulations were within three dilutions higher than those against conidia for almost all isolates of Aspergillus spp. (P < 0.01). In contrast, the differences in the in vitro efficacies of amphotericin B were the lowest for Aspergillus spp. This study demonstrates the importance of the type of inoculum used to test antifungal susceptibilities of Aspergillus spp. The significance of these results for in vivo outcome needs to be determined.


Subject(s)
Amphotericin B/pharmacology , Antifungal Agents/pharmacology , Aspergillus/drug effects , Aspergillus/growth & development , Humans , Liposomes , Microbial Sensitivity Tests/methods
20.
FEMS Immunol Med Microbiol ; 31(1): 65-71, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11476984

ABSTRACT

Oropharyngeal candidiasis is one of the first and most commonly reported opportunistic infections of untreated AIDS patients. With the introduction of the new antiviral HAART therapy, including HIV protease inhibitors, this mucocutaneous infection is nowadays only rarely observed in treated patients. It was recently shown that HIV protease inhibitors have a direct attenuating effect on Candida albicans secreted aspartic proteinases (Saps), an investigation prompted by the fact that both Sap and HIV protease belong to the superfamily of aspartic proteinases and by the observation that mucocutaneous infections sometimes resolve even in the absence of an immunological improvement of the host. As these Saps are important fungal virulence factors and play a key role in adhesion to human epithelial cells we tried to assess the effect of the HIV protease inhibitors Ritonavir, Indinavir and Saquinavir on fungal adhesion to these cells. The effect on phagocytosis by polymorphonuclear leukocytes was also assessed. Ritonavir was found to be the most potent inhibitor of fungal adhesion. A dose-dependent inhibition of adhesion to epithelial cells was found already at 0.8 microM and was significant at 4 microM or higher, at 500 microM the inhibition was about 55%. Indinavir and Saquinavir inhibited significantly at 4 microM or 20 microM, respectively; at 500 microM the inhibition was 30% or 50%. In contrast, no protease inhibitor was able to modulate phagocytosis of Candida by polymorphonuclear leukocytes. In conclusion, inhibition of Saps by HIV protease inhibitors may directly help to ease the resolution of mucosal candidiasis. In future, derivatives of HIV protease inhibitors, being more specific for the fungal Saps, may form an alternative in the treatment of mucosal candidiasis insensitive to currently available antimycotics.


Subject(s)
Aspartic Acid Endopeptidases/antagonists & inhibitors , Candida albicans/drug effects , HIV Protease Inhibitors/pharmacology , Candida albicans/pathogenicity , Candida albicans/physiology , Cell Adhesion/drug effects , Dose-Response Relationship, Drug , HeLa Cells , Humans , Indinavir/pharmacology , Neutrophils/drug effects , Neutrophils/immunology , Phagocytosis , Ritonavir/pharmacology , Saquinavir/pharmacology
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