Time filter

Source Type

Staniszewska M.,Narodowy Instytut Zdrowia Publicznego
Przegla̧d epidemiologiczny | Year: 2012

Candida albicans is the most common etiological factor of opportunistic human fungal infections. In this review, we focus on the major virulence factors that mediate the pathogenesis of C. albicans. Among these virulence factors, secreted aspartyl proteases, adherence, pleomorphism are the most important features of C. albicans infections. Ability to exist as different pleomorphic forms is defined as pleomorphism. A number of quorum sensing (QS) molecules have been described which affect morphogenesis process in C. albicans. Furthermore, the morphological transition of C. albicans in response to changing environmental conditions represent a means by which the strain adapts to different biological niches. Furthermore, every morphotype has own virulence profile and each pleomorphic form provide critical functions required for pathogenesis. Candida albicans is a producer of extracellular hydrolytic enzymes. Among them lipases, phospholipases and secreted aspartyl proteinases (Sap) are most significant in virulence. Sap proteins contribute to pathogenesis by digestion of host cell membranes and molecules of the host immune system to avoid antimicrobial attack by the host. One of the key features in the development of candidiasis is adhesion ofC. albicans to buccal and vaginal epithelial cells. The adhesion to host cells represents the first step in the internalization process which involves adhesins. Knowledge of the role of the various C. albicans' virulence factors during in vivo infections is still incomplete, therefore further studies including quantification of genes expression and histopathological examination of tissues damage are required to fully understand pathogenesis of this opportunistic pathogen. Source

Introduction: Over 8000 cases of tuberculosis (TB) are diagnosed annually in Poland. People infected with Mycobacterium tuberculosis (MTB) have a risk of active disease around 10% during whole life, the risk is biggest in the first two years after infection. Recognizing infection before TB disease occurred enables prophylaxis against its activation and ceases transmission of infection. Knowledge about proportion of infected people in the population is crucial to predict the number of new cases of active disease. Material and methods: Prevalence of latent TB infection (LTBI) was tested in 700 healthy adult inhabitants of Mazovia Region in different age groups, using both tuberculin skin test (TST) and interferon gamma release assay (IGRA). Commercial test QuantiFERON®-TB-Gold In Tube (QFT) was used. All participants were mandatory BCG vaccinated according to Polish vaccination schedule. Results: Twenty three per cent of participants tested positively for QFT, which was significantly less than positive results of TST (50.3%). Prevalence of positive QFT result increased with age, as does the incidence of TB in Poland. Positive QFT was most frequent in the oldest age group (48.8%) and rare in the youngest (7.1%). On the contrary, positive TST occurred more often in younger participants (45%), who rarely suffer from TB. Among people over 60, who have the highest TB incidence rate, only 33.8% tested positively with TST. Concordance between both tests was low, with kappa value 0.198. Prevalence of LTBI defined as positive QFT among health care workers (HCW) was significantly higher than in other participants (32.2% v. 20.4%, p < 0.01). Conclusions: LTBI was diagnosed in 23.3% of tested population of Mazovia Region. QFT is a better tool for diagnosing LTBI as it shows positive correlation with age, the same as incidence of TB disease does. Concordance between both tests is low. Prevalence of LTBI in HCW is higher than in other participants. © 2011 Via Medica. Source

C. diphtheriae, C. ulcerans and C. pseudotuberculosis are closely related species possessing the ability to produce the lethal diphtheria toxin. The toxin is considered as the main virulence factor, but these species express also other virulence factors so nontoxigenic strains of the species are also able to cause serious infections. The interest in the virulence factors other then diphtheria toxin has been increasing and new factors and virulence mechanisms have been investigated. This paper is an overview of C. diphtheriae, C. ulcerans and C. pseudotuberculosis infections in humans, presenting the mechanism of action of diphtheria toxin adhesive factors, iron uptake systems and other putative virulence factors. Source

Teunis P.F.M.,Center for Infectious Disease Control | Teunis P.F.M.,Emory University | Falkenhorst G.,Statens Serum Institute | Ang C.W.,VU University Amsterdam | And 10 more authors.
Epidemiology and Infection | Year: 2013

As a major foodborne pathogen, Campylobacter is frequently isolated from food sources of animal origin. In contrast, human Campylobacter illness is relatively rare, but has a considerable health burden due to acute enteric illness as well as severe sequelae. To study silent transmission, serum antibodies can be used as biomarkers to estimate seroconversion rates, as a proxy for infection pressure. This novel approach to serology shows that infections are much more common than disease, possibly because most infections remain asymptomatic. This study used antibody titres measured in serum samples collected from healthy subjects selected randomly in the general population from several countries in the European Union (EU). Estimates of seroconversion rates to Campylobacter were calculated for seven countries: Romania, Poland, Italy, France, Finland, Denmark and The Netherlands. Results indicate high infection pressures in all these countries, slightly increasing in Eastern EU countries. Of these countries, the differences in rates of notified illnesses are much greater, with low numbers in France and Poland, possibly indicating lower probability of detection due to differences in the notification systems, but in the latter case it cannot be excluded that more frequent exposure confers better protection due to acquired immunity. © Cambridge University Press 2012. Source

Gorski J.,University Im ckiewicza znaniu | Latour T.,Narodowy Instytut Zdrowia Publicznego | Siepak M.,University Im ckiewicza znaniu | Drobnik M.,Narodowy Instytut Zdrowia Publicznego | Sziwa D.,Narodowy Instytut Zdrowia Publicznego
Biuletyn - Panstwowego Instytutu Geologicznego | Year: 2012

The Miocene aquifer formations of the Wielkopolska region are marked by the zonal occurrence of "brown water" with the colour intensity ranging from several hundred to several thousand mg Pt/1. Its origin is linked to the presence of organic matter dispersed in the sand formations, and the zonal character of its occurrence results from the paleohydrogeological conditions of water circulation and exchange. Brown water is not suitable for drinking purposes, and its co-occurrence with the water of low colour intensity impedes the exploitation of usable water. However, in view of the conducted pharmacodynamic analysis, such water shows high biological activity and has beneficial influence on living organisms. Therefore, it can be applied in balneotherapy. The article presents basic information on the occurrence and origin of brown water in the Wielkopolska region, as well as the results of preliminary chemical analyses of brown water collected from five selected wells. The study revealed that brown water containing humus substances amounting to over 200 mg/1 and showing high colour durability following its collection from the water-bearing layer is especially useful for the purposes of therapy. Such water was found in two out of the five studied wells, and it can be used for baleotherapeutical purposes. Source

Discover hidden collaborations