Concurrent weekly cisplatin and simultaneous integrated boost intensity-modulated radiotherapy of locally advanced squamous cell carcinoma of the head and neck.

BACKGROUND: Radiotherapy of locally advanced head and neck cancer represents a major clinical challenge. Any treatment intensification aiming at improved treatment outcomes poten-tially results in a higher toxicity. The search for optimal treatment schedule involving conventional or altered fractionation of radiotherapy and the frequency and dose of concomitant cisplatin or other systemic agents has been spanning over several decades. PURPOSE: To evaluate long-term outcomes and toxicity of accelerated chemoradiotherapy of locally advanced squamous cell carcinoma of the head and neck (LA SCCHN). PATIENTS AND METHODS: Forty patients with stage III and IVA (TNM, 7th Ed.) LA SCCHN were treated with accelerated radiotherapy with a total dose of 67.5 Gy in 6 weeks delivered with simultaneous integrated boost intensity-modulated radiotherapy (SIB IMRT) and concomitant weekly cisplatin 40mg/m2. Five-year outcomes and early and late toxicity were evaluated. RESULTS: With the median follow-up of 47.8 months, a 5-year locoregional control rate (LCR) was 56.5%, distant control rate (DCR) was 87% and 5-year progression-free survival (PFS) and overall survival (OS) were 37 and 45%, respectively. Cisplatin cumulative dose of 200mg/m2 was administered in 83% of patients. Grade 2 late toxicity with dietary change was observed in 21 (53%) patients. Human papillomavirus (HPV) status determined by p16 immunohistochemistry was the only significant factor in 5-year treatment outcomes analysis with LCR 100 vs. 41% (P < 0.01), DCR 100 vs. 78% (P = 0.154), PFS 80 vs. 23% (P = 0.01) and OS 80 vs. 34% (P = 0.03) for HPV positive oropharyngeal cancer (OPC) and other HPV negative LA SCCHN. CONCLUSION: High proportion of patients with LA SCCHN received an adequate cumulative dose of concurrent cisplatin with accelerated radiotherapy with SIB IMRT. This study demonstrated that chemoradiotherapy with weekly cisplatin resulted in favorable local control rate and survival in patients with HPV+ OPC.

Radical external beam reirradiation of recurrent head and neck cancer.

BACKGROUND: Recurrent head and neck carcinomas represent a therapeutic challenge for the surgeons as well as for the treating radiation oncologists. Despite advances in the treatment of newly dia-gnosed head and neck carcinomas, relapses occur very frequently and contribute significantly to patient mortality. External beam reirradiation is still considered to be a controversial therapeutic intervention. Historically, in the era of 2- and 3-dimensional conformal radiotherapy, its narrow therapeutic ratio has long led to a general concern that the potential benefit could not sufficiently outweigh the high risk associated with the treatment. The unfavorable therapeutic ratio, however, could be positively influenced by the use of modern techniques of intensity-modulated radiation therapy (IMRT), volumetric-modulated arc therapy (VMAT), stereotactic body radiation therapy (SBRT) and heavy-ion radiotherapy (protons, carbon ions). PURPOSE: The purpose of this review is to create a practical tool for clinical decision-making on the type of patient suitable for reirradiation and the exact type of radiotherapy technique with respect to its expected therapeutic effect, toxicity profile and availability throughout the institutions. In the introductory section, selection of patients is defined with an emphasis on factors that significantly affect overall survival and may be particularly useful in shared decision-making approach within multidisciplinary teams. Furthermore, the text deals with the individual types of external beam radiotherapy techniques (IMRT, SBRT, heavy-ion radiotherapy) with a clear summary of therapeutic outcomes and toxicity from published scientific evidence that had a significant impact on clinical practice.

Significance of transcriptionally-active high-risk human papillomavirus in sinonasal squamous cell carcinoma: Case series and a meta-analysis.

Sinonasal cancers represent a highly heterogeneous group of head and neck cancers, for which etiological and prognostic significance of high-risk human papillomavirus (HPV) infections has not yet been conclusively established. We investigated the presence of transcriptionally-active high-risk HPV in a series of 34 sinonasal squamous cell cancer (SNSCC) cases and evaluated the effect of transcriptionally-active HPV on the overall survival. In addition, we performed a meta-analysis of previously published studies, including this study, to summarize the prevalence of HPV positivity across histological subtypes of SNSCC. The presence of transcriptionally-active HPV was detected by HPV mRNA using the polymerase chain reaction (PCR) or in situ hybridization (ISH). p16 expression was evaluated as a surrogate marker for transcriptionally-active HPV infection by immunohistochemistry (IHC), the presence of high-risk HPV DNA was tested by PCR and the HPV genotypes were determined by sequencing of PCR amplicons. Transcriptionally-active HPV infections were found in ~25% of the SNSCC cases. The role of HPV infection in keratinizing SNSCC may be higher than previously reported (~32% in our study vs. ~0-6.3% in all other studies). Patients with transcriptionally-active HPV-positive SNSCCs were more likely to be diagnosed at earlier stages (p<0.05) and displayed better mean overall survival, although the difference between HPV-positive and HPV-negative groups was not statistically significant. In contrast to other non-oropharyngeal squamous cell carcinomas (non-OPSCCs) of the head and neck, in SNSCCs, p16/IHC and p16/IHC+HPV DNA displayed high specificity as surrogate markers of transcriptionally-active HPV infections. However, p16/IHC may have significantly lower sensitivity as a surrogate marker of transcriptionally-active HPV in SNSCCs compared to OPSCCs. Furthermore, in our group of SNSCCs, all cases positive for high-risk HPV DNA by PCR were also transcriptionally-active (causative) infections with positive HPV mRNA by ISH. Our results imply a possible different role of HPV-mediated carcinogenesis of squamous cell epithelium in oropharyngeal and sinonasal sites with the latter displaying a lower proportion of causative HPV infections; nevertheless, most cases positive for high-risk HPV DNA, p16/IHC or combination thereof were also found positive for transcriptionally-active HPV. The prognostic significance of HPV status in SNSCCs remains inconclusive and future studies should investigate the presence of transcriptionally-active HPV by direct HPV testing.

Human papillomavirus and Epstein-Barr virus in nasopharyngeal carcinoma in a non-endemic eastern european population.

Nasopharyngeal carcinoma (NPC) is a rare malignancy in the Czech Republic and Slovakia, with the standardized incidence rate of < 1:100000 person-years. Viral status of NPC in these non-endemic Eastern European regions is currently unknown. In a retrospective study, we evaluated the presence of EBV and HPV in 62 NPC cases. EBV status was determined by the use of in situ hybridization (ISH) for EBV encoded small RNA 1 (EBER1). HPV status was examined with p16 immunohistochemistry, DNA ISH and DNA polymerase chain reaction. Sixty-one studied cases showed non-keratinizing morphology and one was keratinizing squamous cell carcinoma. Only one NPC with non-keratinizing morphology was scored as p16-positive (nuclear and cytoplasmic staining ≥ 70% of tumor cells). This case was positive for high-risk HPV by ISH and the DNA PCR confirmed the presence of HPV18 type. At the same time, this case was found negative for EBV. Remaining sixty-one cases that were scored as p16-negative were all found HPV-negative by ISH and the DNA PCR. EBV was detected in 85.5% (53/62) of cases and 9 cases were EBV-negative, including the case of keratinizing NPC. In contrast with previous reports on the prevalence of EBV-positivity in Caucasian patients with NPC, the majority of patients coming from this non-endemic region show EBV-positivity; therefore, they may be candidates for novel EBV-targeting therapies. Conversely, HPV-positive NPC is very rare and HPV does not seem to play a significant role in the etiopathogenesis of NPC in these Eastern European populations.

Prediction of toxicities of prostate cancer radiotherapy.

UNLABELLED: We treated a cohort of 116 patients with prostate cancer with three-dimensional conformal hypofractionated radiotherapy to a total dose of 52.8 Gy in 16 fractions (3.3 Gy per fraction). The correlation between acute and late gastrointestinal (GI) and genitourinary (GU) toxicity and dose-volume parameters was analysed. Comparison of observed incidence of toxicity and normal tissue complication probability calculated from dose-volume histograms (DVH) of all patients using radiobiological Lyman-Kutcher-Burman model was performed. The results of our study suggest that acute gastrointestinal toxicity ≥ grade 2 (G2) is the significant predictor of late toxicity ≥ G2 (p=0.006). Observed incidence of acute and late GI toxicities ≥ G2 was 9.7% and 11.5%, respectively. NTCPs of acute and late GI complications ≥ G2 were 11.3% and 2.5%. Observed incidence of late GU toxicity ≥ G2 was 14.2%, NTCP was 0.8%. Comparison of calculated probability of acute GI toxicity ≥ G2 and observed incidence indicates that parameters of radiobiological models are set appropriately. Comparison of observed incidence of late GI and GU complications ≥ G2 and calculated NTCPs shows the need of refinement of LKB model parameters for acute and late GI and GU complications ≥ G2. KEYWORDS: prostate cancer, radiotherapy, acute and late toxicity, radiobiological modeling.

Molecular diagnosis of Toxoplasma gondii in pregnant women.

BACKGROUND: Novel approaches in the diagnostics of T. gondii have enabled a detection of the parasite in the amniotic fluid or blood of pregnant women. OBJECTIVE: The high titres of IgM and IgG antibodies against T. gondii are not always indicative of the presence of this parasite in pregnant women, therefore the molecular assays can be used to diagnose and genetically characterise T. gondii in amniotic fluids and blood samples. METHODS: The study analysed 15 samples of amniotic fluid and 1 sample of the blood from pregnant women suspected for toxoplasmosis. The serological ELISA test was used for the immunological study and molecular analyses, PCR at SAG2 locus followed by RFLP analysis were used for Toxoplasma gondii genotyping. CONCLUSION: Using PCR assay with TGR1E gene we have confirmed the presence of T. gondii in the blood of a pregnant woman. The parasite was typed as genotype I, belonging to virulent strains (Tab. 1, Fig. 2, Ref. 30).

Dirofilaria infections in working dogs in Slovakia.

A monitoring programme aimed at the diagnosis of subcutaneous dirofilariasis and heartworm disease in working (police and military) dogs in Slovakia has been performed during the period of September 2007 to February 2008. In co-operation with the Ministry of the Interior and the Ministry of Defence, in total, 710 dogs (591 police dogs and 119 military dogs) were investigated for the presence of microfilariae in blood. All police and military dogs in active service held on the territory of Slovakia were included. Microfilariae were detected in 118 (20.0%) police dogs and 10 (8.4%) military dogs. The most infected individuals originated from southern parts of Slovakia (Trnava region 53.6% and Nitra region 39.6%); the prevalence was low in northern regions (Zilina 3.1% and Presov 6.6%). In several districts of southern Slovakia, the prevalence of subcutaneous dirofilariasis in working dogs exceeded 40%. In all infected animals, the autochthonous origin of the disease was confirmed; however, due to the frequent movement of working dogs, it was not possible to identify the exact locality of infection. At present, a dog living in Nemsová village in Trencín district (north-western part of the country) is regarded as the northernmost localized autochthonous case of subcutaneous dirofilariasis in Slovakia. In three dogs, co-infection of Dirofilaria repens and Dirofilaria immitis was detected. High prevalence rates in working dogs and the zoonotic characteristic of the disease represent an undoubtedly important veterinary and medical problem that requires the urgent introduction of prophylactic and control measures.

The first finding of Neospora caninum and the occurrence of other abortifacient agents in sheep in Slovakia.

Neosporosis is an infection of animals caused by an intracellular coccidian parasite, Neospora caninum, closely related to Toxoplasma gondii. The parasite is one of important abortifacient agents of bovine abortions worldwide. The aim of the study was to detect the prevalence of anti-Neospora antibodies in dairy aborting sheep from two eastern Slovak regions and to compare it with the occurrence of other potential abortifacient agents. Sera of 382 sheep, mainly the Improved Valachian and Merino breed, were tested for the presence of anti-Neospora and anti-Toxoplasma antibodies by ELISA, anti-Leptospira sp. by micro-agglutination-assay and anti-Chlamydophila antibodies using the complement fixation test. The mean seroprevalence of N. caninum was 3.7% and of T. gondii, 24.3%. This phenomenon of higher susceptibility of sheep to T. gondii is in the opposite of N. caninum infection in cattle. Anti-Leptospira antibodies were observed in 2.9% of serum samples with titres from 800 to 1600, whereas IgG antibodies against Chlamydophila abortus were found in 13.6% with titres from 64 to 1024. Half of N. caninum positive sera were simultaneously positive for T. gondii and one sample for C. abortus. From examined abortifacient agents the most important, from the frequency point of view, were toxoplasmosis (24.3%) and chlamydiosis (13.6%). No significant association between the frequencies of the abortions and mean seroprevalence of the abortifacient agents in Kosice region was determined. Likewise, no significant differences between the mean seroprevalence of neosporosis and toxoplasmosis in the two regions were detected. The first survey of neosporosis in aborting sheep from eastern Slovakia revealed a low prevalence resulting in a lower impact on reproduction losses in these small ruminants.

Cystic echinococcosis in Turkey: genetic variability and first record of the pig strain (G7) in the country.

A sample of 22 Echinococcus granulosus isolates collected from 12 sheep and ten humans from a focus of cystic echinococcosis in western Turkey was examined by DNA sequencing of four mitochondrial genes (cox1, atp6, nad1, rrnS). Results demonstrated the presence of two species of E. granulosus complex, E. granulosus sensu stricto and E. canadensis. Of E. granulosus sensu stricto, the G1 genotype (including three microvariants) was found in 17 isolates from humans and sheep, the G3 genotype and an intermediate form G1/G3 in one isolate each (both from sheep). Of E. canadensis, the pig strain G7 was found in three isolates from sheep and human. This is the first report of this strain in Turkey. Its presence has implications for local control programs due to its shorter maturation rate in dogs compared with E. granulosus sensu stricto. Goat and/or wild boar are likely reservoirs for G7 in the region. We provided further data on the pattern and frequency of nucleotide substitutions within the G1/G3 cluster. Based on our results and GenBank records, G2 (Tasmanian sheep strain) is not considered as a discrete genotypic unit, as its sequences at polymorphic sites conform to microvariants of both G1 and (more often) G3.

The first finding of Echinococcus multilocularis in dogs in Slovakia: an emerging risk for spreading of infection.

Alveolar echinococcosis, caused by the metacestode Echinococcus multilocularis, is a zoonosis of public health significance. Apart from red foxes, other carnivore species can also serve as definitive hosts of this parasite. This study aimed to determine the occurrence of E. multilocularis in dogs in the Slovak Republic and identify risk factors for acquiring the infection. Out of 289 dogs examined, E. multilocularis was detected in eight samples (2.8%). Positive results were observed in shepherd dogs (12.5%), guard dogs (7.1%), hunting dogs (2.4%) and in one dog with unknown usage (2.5%). Catching rodents and feeding with raw viscera were confirmed to be the most important risk factors for E. multilocularis infection. On the contrary, the way of dog use, frequency of going to the rural areas, the age and gender of animals seem not to be risk factors for infection. No significant association was observed between the positivity of dogs coming from high endemic or non-endemic regions. This is the first report of E. multilocularis in dogs in the Slovak Republic that confirms substantial contribution of dogs to the transmission of the tapeworm in this territory and urges the necessity of prophylactic measures for dog owners.

Long-term survey on Trichinella prevalence in wildlife of Slovakia.

In Slovakia, monitoring the prevalence of Trichinella spp. in wildlife was performed since 2000 in the main reservoir animals, the red fox (Vulpes vulpes) and wild boar (Sus scrofa), using artificial digestion method as recommended by International Commission on Trichinellosis. The results of investigation performed in 5270 red foxes showed that Trichinella infection is widespread across Slovakia and prevalence increased significantly from 4.9% in 2000 to 20.5% in 2007. Recently, a higher Trichinella prevalence (0.11%) in wild boars was also demonstrated. The results indicate that foxes and wild boars are involved in the spread of Trichinella, although the latter host species seems to play a secondary role in the maintenance of the sylvatic cycle in Slovakia. Trichinella britovi is the predominant species circulating in Slovakia, both in foxes and wild boars, and Trichinella spiralis occurs only sporadically. Mixed infections of T. britovi and Trichinella pseudospiralis were recorded in 2005 in one wild boar from Eastern Slovakia and in 2006 in one red fox from the same region. These findings are important with respect to an outbreak caused by T. pseudospiralis in a pig farm in the same district 3 years ago. This study provides a complex picture on Trichinella occurrence in all regions of Slovakia and may be a good basis for evaluating the risk of parasite transmission to the domestic cycle and human beings.

Neospora caninum, potential cause of abortions in dairy cows: the current serological follow-up in Slovakia.

Neosporosis is considered to be a contributing risk factor for abortions in dairy cows and other farm animals and has negative economic impact on their breeding. In respect of the rapid spread of neosporosis in herds throughout the world, our aim was to detect the prevalence of anti-Neospora antibodies in cows post-abortion (PA) (PA Group n=716) and in cows without any reproduction problems (Control Group n=247) on large breeding farms from Eastern Slovakia. The overall mean seropositivity in PA Group (20.1%) was significantly higher (p<0.0001) in comparison with the Control Group (2.3%), and this demonstrates the causal dependency of abortions on neosporosis. On farms from south-east region, 15.6% of cows were seropositive on average ranging from 7.8% to 25.8% in different districts. In the northern region, significantly (p=0.0002) higher 26.2% mean seropositivity was detected. The seroprevalence in different districts ranged from 2.9% to 39.4%. In the PA Group a high seropositivity to infectious bovine rhinotracheitis (41.5%) and sporadic occurrence of Q-fever, leptospirosis and chlamydiosis was also detected. From 11 Toxoplasma-seropositive cows, only one animal was simultaneously positive to Neospora. The relatively high prevalence rate in cows warrants the attention and a need of surveillance in Slovak herds. A better knowledge of epidemiology of this etiological agent and the mechanisms of its transmission may help in the introduction of more effective preventive and control measures.

First case of cutaneous human dirofilariosis in Slovak Republic.

Dirofilariosis is a zoonotic disease caused by several species of the genus of Dirofilaria. The causative agent initiates a dangerous canine disease reported from many parts of the globe. The parasites are transmitted by arthropods, which act either as a vector or intermediate hosts. In humans the parasites do not usually reach the adult stage but microfilaremia is absent because of mating impossibility. Human dirofilariosis is caused by D. immitis or D. repens and has been reported from many parts of the world including European countries, namely Italy, France, Spain and Greece. Sporadically, this parasitosis is detected in Central European countries such as Hungary and Switzerland. The presented paper reports the first case of human cutaneous dirofilariosis in Slovakia. The clinical manifestation was a typical subcutaneous granuloma with the adult worm in the center. The identification of Dirofilaria repens was made based on morphological appearance of the parasite. The patient 60 years old, lives in the area where in 2005 six cases of canine dirofilariosis caused by the same species were reported (Fig. 2, Ref. 16).

Trichinella spiralis-outbreak in the Slovak Republic.

BACKGROUND: Trichinellosis is a zoonosis caused by nematode worms of the genus Trichinella and acquired through the consumption of raw or undercooked meat or meat products that harbour parasite larvae. The present report was designed to evaluate the course and circumstances surrounding the trichinellosis outbreak that occurred due to consumption of pork from a backyard pig in the southwest area of Slovakia in 2001. PATIENTS AND METHODS: Patients suspected of acquiring infection were serologically examined by ELISA, sera of patients with symptoms of clinical trichinellosis were additionally tested by Western Blot. In symptomatic patients haematological and biochemical parameters were assessed on day 45 p.i. RESULTS: An epidemiological investigation showed that the disease was linked to the consumption of infected pork and/or smoked pork products and affected the household members of four families. Out of 23 persons who had consumed the infected meat, 11 showed anti-Trichinella IgA, IgM and IgG antibodies in their sera by an ELISA against somatic and excretory-secretory antigens. Six of them developed clinical symptoms. Sera from symptomatic patients recognised bands of 64, 47, 45 and 43 kDa of crude T. spiralis antigens by Western blot. Using multiplex PCR analysis, parasite larvae isolated from pork were identified as T. spiralis, rarely occurring in Slovakia. CONCLUSION: The outbreak of human trichinellosis in an area where feral animals have been previously considered free of Trichinella was unexpected. Following the suspicion of trichinellosis being addressed, larvae were detected in meat and meat products from pig and the course of disease in patients was successfully controlled and managed.

Echinococcus multilocularis in the red fox Vulpes vulpes from the East Carpathian region of Poland and the Slovak Republic.

The occurrence of Echinococcus multilocularis in the Poland-Slovak frontier zone of the East Carpathian region was assessed, for comparison with that in adjacent regions in both countries. A total of 392 red foxes from Poland and 427 red foxes from the Slovak Republic were examined from 2001 to 2004. Significant differences in prevalences were observed in foxes captured from the borderland and adjacent zones in both countries. The mean prevalence of E. multilocularis in the Polish borderland reached 45.7+/-18.6% and in the Slovak border 35.0+/-10.7%. In both countries, the prevalence of E. multilocularis in red foxes from adjacent districts, outside the frontier Carpathian region, was considerably lower (18.9+/-9.2% in Poland and 20.8+/-9.0% in Slovakia). These differences are probably due to geomorphological and ecological factors, which contribute to the survival of the tapeworm eggs and the subsequent spread of infection. The Carpathian regions of northeast Slovakia and southeast Poland are characterized by specific climatic conditions such as low mean annual air temperatures, low temperatures in active soil surfaces, high soil humidities and a high mean annual rainfall.

Influence of Toxocara canis infection during pregnancy on offspring resistance towards re-infection.

The impact of Toxocara canis infection of Balb/c mice mothers on the future immune response of their offspring towards reinfection with the same parasite was studied. Two groups of offspring, the first originating from the mothers infected with a single dose of 1000 Toxocara canis eggs and the second from non-infected mothers, were both challenged with 500 T. canis eggs per animal at 6 weeks of age. The proportions of spleen CD4+ and CD8+ T lymphocytes, the level of serum cytokines IFN-gamma and IL-5, eosinophilia in peripheral blood, the production of specific antibodies and the number of migrating larvae were monitored. In both groups of offspring, the challenge infection resulted in an increase in CD4+ T-cell subtype in comparison with the non-infected healthy control, although after an initial decline a subsequent increase in CD8+ was observed. The immunoregulation index (CD4+/CD8+) was lower in the group of mice originating from infected mothers throughout the whole experiment compared to the offspring of non-infected mothers as well as in healthy control mice of the same age. In the offspring of infected mothers mainly, a reduced production of IFN-gamma and of IL-5, suppressed eosinophilia and a higher level of protective antibodies was detected, compared to the control second group, in which the INF-gamma concentration significantly increased after day 42 p.i. In the first group of offspring before challenge, 12.7 +/- 2.5 larvae in the brains and 32 +/- 2.1 larvae in the muscles transmitted from the infected mothers were detected. There was a significant reduction in larval recovery from brain on days 42 and 49 p.i. (56.7 and 56.8%, respectively), while from muscles in the same time there was a reduction of 46.7 and 39%, respectively, compared to the offspring of non-infected mothers. These results indicate a significant protective memory of immune mechanisms against T. canis induced in offspring of Toxocara-infected mother mice.

Field evaluation of an intravital diagnostic test of Echinococcus multilocularis infection in red foxes.

Echinococcus multilocularis parasitizes the small intestine of red foxes (Vulpes vulpes) and other carnivores, and has a wide distribution throughout the northern hemisphere. This cestode is the causative agent of human alveolar echinococcosis, a life-threatening helminth zoonosis. In 2000-2002, 2130 red foxes were examined for its presence in Slovakia, with a total prevalence of 30.7%. The data on occurrence were obtained by the combination of necropsy of small intestines from red foxes and coproantigen detection in faecal samples. The correlation between the number of detected specimens and the value of optical density of copro-ELISA test was found. When worm burdens were low (1-25 specimens) the sensitivity of the method was 31.3+/-8.64%, when worm burdens were >50 specimens, 81.8+/-0.66%, and with high worm burdens (>1000 specimens) the sensitivity reached 100+/-0.34%. E. multilocularis presence was detected using the nested PCR method from the eggs in the faecal samples with a 100% specificity. In epidemiological surveys of this zoonosis, it is of crucial importance to detect animals with a high level of infection, which are responsible for the bulk of environmental contamination. The advantage of copro-ELISA test lies in allowing the intravital diagnostics to be employed within the epidemiological survey of E. multilocularis occurrence in the protected and urban areas.

First record of Trichinella pseudospiralis in the Slovak Republic found in domestic focus.

Infection of Trichinella spp. is widespread among wildlife in Slovakia and the red fox (Vulpes vulpes) is the main reservoir of Trichinella britovi. Trichinella spiralis has been rarely documented in sylvatic and domestic animals of this country. During routine examination of domestic pigs at the slaughter, Trichinella larvae were detected by artificial digestion in a domestic pig of a large-scale breeding farm in Eastern Slovakia. The parasite has been identified by molecular (PCR) and biochemical (allozymes) analyses and by the morphology of the nurse cell as the non-encapsulated species Trichinella pseudospiralis infecting both mammals and birds. The epidemiological investigation carried out at the farm level revealed the presence of the same parasite species in other three pigs of 192 examined (2.1%), in 3 of 14 (21.4%) examined synanthropic rats (Rattus norvegicus) and in a domestic cat. The farm was characterized by inadequate sanitary conditions, insufficient nutrition, cannibalism and the presence of rat population. A different profile has been observed at the phosphoglucomutase locus in T. pseudospiralis isolates from Slovakia in comparison with the T. pseudospiralis reference isolate from the Palearctic region. This is the first documented focus of T. pseudospiralis from Central Europe. The detection in domestic pigs of a non-encapsulated parasite infecting both mammals and birds stresses the need to avoid the use of trichinelloscopy to detect this infection at the slaughterhouse.

Circulation of Toxocara spp. in suburban and rural ecosystems in the Slovak Republic.

Toxocara spp., the common roundworms of domestic and wild animals, are the causative agents of larval toxocarosis in humans. The migration of Toxocara larvae in men causes clinical syndrome, called larva migrans visceralis or larva migrans ocularis. The objective of the present work was to investigate the prevalence of toxocarosis in dogs, red foxes (Vulpes vulpes), and small mammals in the Slovak Republic. T. canis infection was diagnosed in 16.6% out of 145 dogs examined. Young animals showed significantly higher positivity (50.0%) than adults (12.4%). Coprological investigation of 310 red foxes showed 8.1% prevalence of T. canis, with higher occurrence in animals from rural conditions (8.6%) than from suburban environment (5.6%). Out of 710 small mammals examined, anti-Toxocara antibodies were detected in 7.7% of the animals. The most frequently seropositive species was Apodemus agrarius (15.9%). Seropositivity of small mammals from suburban localities was higher (10%) compared with rural areas (5.8%), with adult animals exhibiting higher seropositivity (8.0%) than subadults (6.8%). Our results have confirmed the importance of dogs, red foxes and small mammals in circulation of this serious helminthozoonosis in suburban and rural ecosystems.

Influence of maternal infection on offspring immune response in murine larval toxocariasis.

The impact of Toxocara canis infection on the proportion of CD4+ and CD8+ T splenocytes, the serum concentrations of cytokine IFN-gamma and IL-5, and the production of Toxocara-specific antibodies were studied in two C57BL6/J mouse groups and their offspring. The mice were infected with 1000 T. canis eggs on the day of mating (early infection) and on day 14 of pregnancy (late infection). Early infection resulted in a significant increase of CD4+ T-cell subtype, however, a decline in CD8+ in comparison with late infection, as well as with non-infected control. The IFN-gamma serum concentrations decreased in infected mothers after the birth when compared with non-infected mothers, while in the offspring this cytokine was barely or not detectable. In the mothers of both infected groups, the humoral immune response included both parasite-specific IgM and IgG2 antibodies. While IgG1 levels remained constant throughout the whole experiment in mothers with early infection, late-infected mothers became seropositive only 3 weeks after delivery. IgM was not detectable in any offspring. Pups from early-infected mothers had IgG1 antibodies. Conversely, IgG2 was detectable in pups of both experimental infection groups. A significant difference was observed in the amounts of pups/litter of the infected mothers in comparison with the non-infected ones. Only 56% of females after early infection and 79% of those after late infection had a successful pregnancy. However, all mice of the control group produced a litter. The first T. canis larvae were detected in the muscles of the offspring of both groups on day 5 after the birth. These data show the changes in regulatory and cytotoxic immunity mechanisms of the infected mothers and their offspring and the high level of pregnancy loss as a result of larval toxocariasis.