Estrogen Receptors Mediated Negative Effects of Estrogens and Xenoestrogens in Teleost Fishes-Review.

Estrogen receptors (ERs) play a key role in many biochemical and physiological processes, that are involved in maintaining organism homeostasis. At the most basic level, they can be divided into nuclear estrogen receptors and membrane estrogen receptors that imply their effect in two ways: slower genomic, and faster non-genomic. In these ways, estrogens and xenoestrogens can negatively affect animal health and welfare. Most of the available literature focuses on human and mammalian physiology, and clearly, we can observe a need for further research focusing on complex mutual interactions between different estrogens and xenoestrogens in aquatic animals, primarily fishes. Understanding the mechanisms of action of estrogenic compounds on the ERs in fishes and their negative consequences, may improve efforts in environmental protection of these animals and their environment and benefit society in return. In this review, we have summarized the ER-mediated effects of xenoestrogens and estrogens on teleost fishes metabolism, their carcinogenic potential, immune, circulatory, and reproductive systems.

The effect of infectious agents on the prevalence of allergies.

PURPOSE: The role of infectious agents in allergy development is ambivalent. On one hand, there are reports of an association between a previous infection (especially a viral respiratory tract infection) and developing hypersensitivity to inhaled allergens, which in turn may increase the risk of developing allergic reactions. On the other hand, there are reports emphasizing a protective effect of a number of infectious agents against allergy development. The aim the study was to find possible associations between a past infectious or parasitic disease and an allergic condition. MATERIAL AND METHODS: The study population was a group of 18,648 subjects. The study, which was a part of the project: 'Implementation of a System for the Prevention and Early Detection of Allergic Diseases in Poland', was conducted in 9 selected regions of Poland and used the ECRHS and ISAAC questionnaires adapted for Europe. The following statistical tools were used: Pearson's chi-squared test, Fisher's exact test, and logistic regression. RESULTS: This research was an attempt to clear association between a history of measles or viral hepatitis and the likelihood of developing asthma, especially in males (χ2 = 5.29; p<0.05). Past parasitic disease showed a clear association with a suspected allergic rhinitis in various groups of patients (differing both in terms of sex and age). CONCLUSIONS: A history of some forms of either infectious or parasitic diseases has a measurable effect on the risk of developing allergies.

Seroprevalence of six pathogens transmitted by the Ixodes ricinus ticks in asymptomatic individuals with HIV infection and in blood donors.

The objective of our study was to estimate the seroprevalence of six pathogens transmitted by ticks in HIV-infected persons and blood donors in Poland (B. burgdorferi s.l., A. phagocytophilum, Ehrlichia spp., Babesia spp., Rickettsia spp. Bartonella henselae) to assess the frequency of exposure to such microorganisms in immunocompetent and immunocompromised individuals in endemic regions for I. ricinus ticks. Serum samples were collected from 227 HIV-infected patients and 199 blood donors. All samples were analyzed for antibodies against six tick-borne pathogens and seroprevalence rates were statistically compared between two tested group as well as age, sex and lymphocyte T CD4+ level in HIV infected patients. The seroprevalence of tick-borne infections in HIV-infected patients is higher than that of the healthy population in Poland, although no association between serological status of patients and lymphocyte CD4+ T cell level has been observed. The frequency of tick-borne coinfections and doubtful results of serological tests were significantly higher in HIV-positive individuals. In Poland, the possibility of tick-borne diseases transmission with blood is rather negligible.

Risk factors and control of intestinal parasite infections in sled dogs in Poland.

Training and racing constitute serious challenges for working sled dogs. Attainment of the highest levels of stamina and speed are possible only by completely healthy dogs. Infections with nematodes as whipworm Trichuris sp. or hookworms Uncinaria/Ancylostoma can significantly reduce the fitness of working dogs leading to anemia or even to death. In the middle of the racing season, between December 2009 and April 2010, 108 individual fecal samples were collected from 25 sled dog kennels situated in different regions of Poland. Saturated salt flotation was performed for helminth egg detection. The immunofluorescent assay MeriFluor Cryptosporidium/Giardia and nested PCRs on 18S rRNA (Cryptosporidium spp.) and TPI gene (Giardia spp.) were carried out for detection of intestinal protozoa. Overall prevalence of 6 species of intestinal parasites was 68% in sled dogs (73/108). In 51 samples the eggs of a single species of helminth were detected (47%), two nematode species were detected in 13%, three species of nematodes were found in two dogs. The most prevalent helminths were the hookworms Uncinaria/Ancylostoma-identified in 36% of kennels, and in 34% of sled dogs. Toxocara eggs were detected in 36% of kennels, in 17% of dogs. Trichuris sp. eggs were found in 20% of kennels (5/25), in 13% of dogs. Cysts/oocysts of intestinal protozoa were detected in 31% of sled dogs. The most prevalent was Giardia spp. infection-in 54% of kennels [13/24], in 28% of dogs. Cryptosporidium spp. infections were identified in 37.5% of kennels [9/24], in 13% of dogs. Two sequenced Giardia isolates presented 100% homology with G. intestinalis Assemblage C isolate (AY228641.1), specific for dogs. A range of factors was shown to affect the prevalence of intestinal parasites in sled dogs. The highest prevalence of parasites was found among dogs from large kennels (housing >3 dogs), in dogs less than 2 years old, and in kennels, where prophylactic treatment was carried out 1-4 times a year. The present study has demonstrated a high prevalence of intestinal parasites in working sled dogs in Poland, including the zoonotic human pathogens Toxocara or Cryptosporidium.

Genotyping of Cryptosporidium isolates from human clinical cases in Poland.

Cryptosporidium spp. infection is usually self-limited in immunocompetent hosts but can be severe and life threatening in children and in immunocompromised individuals including those with primary or acquired immunodeficiencies. One hundred and three faecal samples were collected from 35 hospitalised patients with different symptoms and tested for the presence of the parasite. Cryptosporidium oocysts were found in four of 35 patients (11.4%) using Ziehl-Neelsen staining of faecal smears and immunofluorescence assay, whereas 12 (34.3%) samples tested positive by nested polymerase chain reaction assay. Cryptosporidium DNA was detected in one bile sample but not in a liver tissue biopsy sample collected from a patient who suffered from sclerosing cholangitis. Sequence analysis of oocyst wall protein and beta-tubulin gene fragments revealed three different parasite species (Cryptosporidium hominis, Cryptosporidium meleagridis and Cryptosporidium parvum) in children with primary immunodeficiencies, whereas only C. parvum was found in immunocompetent individuals and in those with secondary immunodeficiencies. This study has revealed a high prevalence of Cryptosporidium infection in hospitalised patients in Poland and confirmed that molecular techniques enable a more sensitive detection of the parasite.

[Semi-aquatic animals as a source of water contamination with Cryptosporidium and Giardia]. / Zwierzeta ziemnowodne jako zródlo zanieczyszczenia wody Cryptosporidium i Giardia.

Cryptosporidium and Giardia spp. are parasitic protozoa localized in the alimentary tract of many animal species and humans. Each of these parasite species produces very resistant invasive forms (cysts and oocysts) excreted to the environment with feces of infected hosts. Water contaminated with cysts/oocysts constitutes one of the main transmission routes and is responsible for the majority of infections in humans. Cryptosporidium and Giardia spp. were found in many different species of animals, including livestock, pets and free living animals. The aim of our study was to determine the prevalence of these protozoa in selected species of semi-aquatic mammals and to estimate their role in water contamination. In years 1996-98 the prevalence of Cryptosporidium and Giardia infections was high in muskrats (Ondatra zibethicus) (58 and 87%, respectively). The origin of animals (farmed or free living) affected the prevalence of both parasites in European beavers (Castor fiber). The prevalence of infection increased in second period of study and was 4 and 19% for Cryptosporidium and 0 and 8% for Giardia spp. in the two studied periods, respectively. Both parasite species were also identified in water vole (Arvicola terrestris) and rat (Rattus norvegicus).

Cryptosporidium infection in patients with primary immunodeficiencies.

BACKGROUND: Cryptosporidium species infection is usually self-limited in immunocompetent populations, but can be severe and life-threatening among immunocompromised individuals, particularly in patients with AIDS and in these patients with primary immunodeficiencies (PIDs). PATIENTS AND METHODS: A group of 5 patients with genetically confirmed hyper-IgM syndrome type 1 (XHIM) and one patient with primary CD4 lymphopenia were enrolled in the study. At least 2 stool samples and a bile sample in one patient were examined for Cryptosporidium oocysts by a modified Ziehl-Neelsen technique, by immunofluorescence assay using a commercial kit, as well as by molecular analysis followed by genotyping. Immunological status at the time of PID diagnosis and the complex picture of disease are presented. RESULTS: Chronic cryptosporidiosis was confirmed in 3 patients with XHIM and in one patient with primary CD4 lymphopenia. Molecular diagnosis showed the presence of C parvum, C hominis, and C meleagridis in analyzed specimens. CONCLUSIONS: Cryptosporidium infection with serious clinical symptoms observed in patients with hyper-IgM syndrome calls for regular, repeated screening in this group of patients.

Distribution of Cryptosporidium and Giardia spp. in selected species of protected and game mammals from North-Eastern Poland.

Cryptosporidium spp. and Giardia spp. are wide-spread pathogens of humans and many species of mammals. The ways of transmission are very complex and difficult to define. Both parasites occur in similar environments and share a broad host range. However, in Poland there is still little known about the epidemiology of these parasites due to the paucity of data on human cases and only few studies in wildlife. The aim of our study was to determine the distribution of two intestinal protozoa in a few species of protected and game mammals in North-Eastern Poland. Additionally, we wanted to compare prevalence and abundance of these parasites between wild and farm animals, and to determine the species/genotypes of Cryptosporidium. Fecal samples collected from protected species (European beaver-22, grey wolf-14, European bison-55, Polish Konik (horse)-5) and game mammals (red deer-52, roe deer-22, boar-5) were examined by IFA. We also studied a group of samples collected from farm animals: beaver-30, red deer-66, Polish konik-5. Cryptosporidium oocysts were identified in 5 of 7 studied animal species (prevalence from 9% in roe deer to 36% in wolves), Giardia cysts in 4 of 6 studied species (prevalence from 1.7% in red deer to 7.7% in European beaver). Sequencing analysis of COWP gene fragment revealed that 5 Cryptosporidium isolates from wolves were C. parvum genotype 2 (zoonotic). The results show the important role of examined species in maintaining the natural sources of Cryptosporidium spp. and Giardia spp. infections in the environment.

Fluorescent in situ hybridization as a tool to retrospectively identify Cryptosporidium parvum and Giardia lamblia in samples from terrestrial mammalian wildlife.

Fecal samples of five terrestrial mammalian wildlife species stored at 4 degrees C or at -20 degrees C for up to 36 months have been tested for human zoonotic enteric parasites (i.e., Cryptosporidium parvum and Giardia lamblia) using combined fluorescent in situ hybridization (FISH) and direct fluorescent antibody techniques. The prevalence of C. parvum and G. lamblia varied from 20 to 63% (mean, 45.8%) and from 13 to 100% (mean, 53.2%), respectively. The prevalence of C. parvum and G. lamblia infections was higher in small rodents (mean, 68.5%) than in other wildlife (mean, 21%). Overall, 31.1% of animals were coinfected, and coinfections were more prevalent in small rodents (mean, 52%) than in other wildlife species (mean, 13.2%). The present study has shown that the FISH assay can be retrospectively applied to fecal samples for the identification of C. parvum oocysts, but is less suitable for the identification of G. lamblia cysts in such samples. Terrestrial mammalian wildlife, particularly small rodents, can contribute to watershed contamination with C. parvum oocysts and G. lamblia cysts. To control contamination, the management of pristine watersheds used for drinking water purposes should incorporate control measures for terrestrial wildlife, especially field rodents residing within such watersheds.

Intestinal macro- and microparasites of wolves (Canis lupus L.) from north-eastern Poland recovered by coprological study.

Wolf scats collected during ecological studies in Mazury lake district in NE Poland were analysed for intestinal micro- and macroparasites. Five nematode species were identified: Ancylostoma caninum (Ercolani, 1859), Uncinaria stenocephala (Railliet, 1884), Trichuris vulpis (Froelich, 1789), Toxocara canis (Werner, 1782) and Toxascaris leonina (von Linstow, 1902). Among cestode species there were identified infections with Dipylidium caninum (Linnaeus, 1785). The overall helminth prevalence was 63.5 % and average intensity was 15.4 +/- 8.0 eggs /1g of sample. The most prevalent parasite was T. vulpis (38.5 %) and the most abundant infections were by T. canis. Almost 55 % of samples (28/51) were positive for C. parvum oocysts and 46.7 % (14/30) for Giardia spp. cysts. The pack factor affected the distribution of some of macro- and microparasites. The identified parasite fauna of wolves in Mazury lake district consists of several micro- and macroparasites of interest for public health.