Anisakid nematodes in dolphins (Cetacea: Delphinidae) from the Baltic Sea area.

Dolphins are rarely observed in the Baltic Sea, making only sporadic appearances as a result of their migrations. The study included six specimens: four white-beaked dolphins Lagenorhynchus albirostris and two striped dolphins Stenella coeruleoalba. Their gastrointestinal tracts were found to contain the nematodes Anisakis simplex (in both species) and Contracaecum sp. (only in the white-beaked dolphins). This is the first record of Anisakidae nematodes in dolphins found in the Baltic Sea.

A global checklist of the parasites of the harbor porpoise Phocoena phocoena, a critically-endangered species, including new findings from the Baltic Sea.

The common harbor porpoise is a widely-distributed marine mammal with three known subspecies, including P. phocoena phocoena, with a clearly distinct and critically endangered (CR) subpopulation from the Baltic Sea (Baltic Proper). As part of an assessment of the condition and health threats of these mammals, it is important to conduct parasitological monitoring. The aim of the study was therefore to compare the data on porpoise parasitofauna from this subpopulation with those on porpoises from other areas. The study included 37 individuals from 1995 to 2019; eight species of parasites were found (prevalence 83.8%, mean intensity 724.2, range 2-3940), with a predominance of lung nematodes - Stenurus minor (94.7%), Torynurus convolutus (69.4%), Pseudalius inflexus (63.8%), Halocercus invaginatus (22.2%); the highest intensity was recorded for S. minor (989, 53-2928). Two species of Anisakidae (Anisakis simplex - 33.3%, Contracaecum sp. - 20.0%) were found in the digestive tracts, which were a new record for this population. The fluke Campula oblonga was found in the livers of 31.3% of porpoises. The tapeworm Diphylobothrium stemmacephalum was also recorded in the intestine of one individual; this is typical for these hosts, but previously undetected in the Baltic subpopulation. Parasites coexisted in numerous hosts, constituting a heavy burden for them. The obtained data were compared with those from the P. phocoena parasitofauna from other regions, based on a compiled checklist (1809-2021) including all species of porpoise parasites (55 taxa). Compared to the worldwide porpoise parasitofauna checklist, the number of parasites found in the nominative subspecies (Baltic Proper subpopulation) is small: including only 10 taxa (eight in the current study). These species are typical of porpoises and usually the most common; however, the level of infection of Baltic porpoises (intensity and total parasite load) is very high, which can undoubtedly have a negative impact on their condition and overall health.

Anisakidae in beluga whales Delphinapterus leucas from Hudson Bay and Hudson Strait.

A total of 190 nematodes was isolated from the stomachs of 13 beluga whales Delphinapterus leucas from the Arctic part of Hudson Bay and Hudson Strait. Infection intensity ranged from 1 to 57 specimens and prevalence was 84.62%. Morphological examination of the nematodes revealed the presence of 3 species: Pseudoterranova decipiens sensu lato, Contracaecum osculatum s.l., and Anisakis simplex s.l. Molecular analysis by PCR-based restriction fragment length polymorphism (PCR-RFLP) resulted in the identification of 4 species: Pseudoterranova bulbosa, Contracaecum osculatum A and C, and Anisakis simplex sensu stricto. The nematodes were present in 3 developmental stages: L3 (159 specimens), L4 (16 larvae), and adults (15 worms: 11 males and 4 females).

Helminthofauna of Ohrid gudgeon (Gobio ohridanus Karaman, 1924) from the Lake Ohrid, Macedonia.

Total, 94 specimens of gudgeon (Gobio ohridanus Karaman, 1924) from the Macedonian part of the Lake Ohrid were examined and 61 fishes (64.89%) were infected with parasites. The presence of 4 parasite species was established: Dactylogyrus cryptomeres f. typica (Monogenea), Cystidicoloides tenuissima and Philometra ovata (Nematoda), and Pomphorhynchus laevis (Acanthocephala). The highest prevalence and intensity of infection was with Dactylogyrus cryptomeres f. typica (59.57%; mean intensity 6.07). The lowest one was with Cystidicoloides tenuissima and Philometra ovata (2.13%; 1.0). Dactylogyrus cryptomeres f. typica is recorded for the first time in the ichthyoparasitofauna of Lake Ohrid and Macedonia.

Histopathological diagnosis in parasitic diseases.

Histopathological research is very important in diagnosing human and animal diseases. Detection of histopathological changes during certain parasitic invasions is particularly important for differential diagnosis and often confirms the presence of parasitic diseases. Such studies allow also to conclude on the primary cause of the disease.

Anisakids of seals found on the southern coast of Baltic Sea.

In the present study 5 grey seals (Halichoerus grypus), 3 common seals (Phoca vitulina) and 1 ringed seal (Pusa hispida) bycaught or stranded on the Polish Baltic Sea coast in years 2000-2006 were investigated for the infestation of parasitic anisakid nematodes. 749 of anisakids were found. The most common were: Contracaecum osculatum (59.3%) and Pseudoterranova decipiens (31.0%). There were also small numbers of Anisakis simplex (0.8%). After performing RFLP three sibling species were found. C. osculatum was identified as C. osculatum C, P decipiens was identified as P. decipiens sensu stricto and A. simplex - A. simplex sensu stricto. Nematodes found in seals were mostly in L4 and adult life stage - both of them were equal with some minor variations among the specimens. Sex ratio was also equal, but there was slight excess of males in some cases. There was a minority of L3 larvae belonging to A. simplex species (0.8%).

Anisakid nematodes of Greenland halibut Reinhardtius hippoglossoides from the Barents Sea.

Parasitic nematodes from the body cavity of 94 Greenland halibut (Reinhardtius hippoglossoides) caught in the Barents Sea were examined. Nematode species were identified using both morphological and molecular methods. Four morphospecies were found: Anisakis simplex s.l., Contracaecum osculatum s.l., Pseudoterranova decipiens s.l., and Hysterothylacium aduncum. The most prevalent were C. osculatum s.l. (89.4%) and A. simplex s.l. (86.2%). Mean intensities for these 2 species were 7.8 and 45.2, respectively. The number of parasites was directly proportional to the fish length. The following 6 parasite species, including 3 cryptic species of Contracaecum sp., were identified using molecular methods: A. simplex sensu stricto, C. osculatum A, C. osculatum B and C (the last 2 as host records for halibut), Pseudoterranova bulbosa, and H. aduncum. Mixed infections of C. osculatum A, B, and C were observed.

Prevalence of zoonotic anisakid nematodes in Inuit-harvested fish and mammals from the eastern Canadian Arctic.

Human anisakidosis is a recognized Arctic zoonosis that is directly related to the consumption of traditional Inuit foods, particularly raw fish. The epidemiology of infections with the zoonotic anisakid nematodes Anisakis simplex and Pseudoterranova decipiens was investigated from August 2007 to July 2009 in Inuit-harvested fish and marine mammals from Inuit regions of Nunavik, Nunavut, and Nunatsiavut, Canada. Fish were tested for anisakid larvae using the pepsin-HCl digestion method, and the stomachs or stomach contents of beluga whales, walruses, and three seal species were examined for anisakids. Anisakids were found in seven of eight fish species, as well as in ringed seals (18.2%; 31/170), bearded seals (75.0%; 12/16), and beluga whales (78.9%; 15/19), but not walruses (0%; 0/15). In fish, the odds of being infected with A. simplex and/or P. decipiens was 68.6 (95% confidence interval, 11.6-627.7) times higher in marine fish than in anadromous fish, after adjusting for length of fish. Negative binomial models were created for animal species with large enough sample sizes and parasite prevalence estimates to assess risk factors associated with anisakid abundance. In seals, the only risk factor significantly associated with increasing anisakid abundance was increasing length (p < 0.01), while in beluga whales, the only significant risk factor was year of capture (p = 0.03). In fish, length was the variable most commonly associated with increased anisakid larval abundance, with longer fish having significantly higher larval abundances than shorter fish of the same species. The presence of A. simplex and P. decipiens in bearded seals, ringed seals, and beluga whales from Inuit hunting grounds suggests that they likely act as definitive hosts for these parasites in these environments. With respect to zoonotic disease risk associated with Inuit country foods, among the species of fish examined, Atlantic tomcod, polar cod, and sculpins represented the greatest risk of foodborne disease from A. simplex and P. decipiens.

The ERalpha coactivator, HER4/4ICD, regulates progesterone receptor expression in normal and malignant breast epithelium.

The HER4 intracellular domain (4ICD) is a potent estrogen receptor (ERalpha) coactivator with activities in breast cancer and the developing mammary gland that appear to overlap with progesterone receptor (PgR). In fact, 4ICD has recently emerged as an important regulator and predictor of tamoxifen response, a role previously thought to be fulfilled by PgR. Here we investigated the possibility that the 4ICD coactivator regulates PgR expression thereby providing a mechanistic explanation for their partially overlapping activities in breast cancer. We show that 4ICD is both sufficient and necessary to potentiate estrogen stimulation of gene expression. Suppression of HER4/4ICD expression in the MCF-7 breast tumor cell line completely eliminated estrogen stimulated expression of PgR. In addition, the HER4/4ICD negative MCF-7 variant, TamR, failed to express PgR in response to estrogen. Reintroduction of wild-type HER4 but not the gamma-secretase processing mutant HER4V673I into the TamR cell line restored PgR expression indicating that 4ICD is an essential PgR coactivator in breast tumor cells. These results were substantiated in vivo using two different physiologically relevant experimental systems. In the mouse mammary gland estrogen regulates expression of PgR-A whereas expression of PgR-B is estrogen independent. Consistent with a role for 4ICD in estrogen regulated PgR expression in vivo, PgR-A, but not PgR-B, expression was abolished in HER4-null mouse mammary glands during pregnancy. Coexpression of PgR and 4ICD is also commonly observed in ERalpha positive breast carcinomas. Using quantitative AQUA IHC technology we found that 4ICD potentiated PgR expression in primary breast tumors and the highest levels of PgR expression required coexpression of ERalpha and the 4ICD coactivator. In summary, our results provide compelling evidence that 4ICD is a physiologically important ERalpha coactivator and 4ICD cooperates with ERalpha to potentiate PgR expression in the normal and malignant breast. We propose that direct coupling of these signaling pathways may have important implications for mammary development, breast carcinogenesis, and patient response to endocrine therapy.

Effect of temperature, NaCl concentration and aeration of solutions on the survivability of II stage larvae of Contracaecum rudolphii Hartwich, 1964.

Determinations were carried out for the effect of temperature, NaCl concentration and aeration of solutions on the survivability of stage II larvae of Contracaecum rudolphii nematode. Stage II larvae hatched from egg shells were placed in tap water as well as in 1% and 3% solutions of NaCl. Part of the culture was run on Petri dishes and aerated each day. The second part was transferred into high beakers and left non-aerated. All cultures were run in three replications at temperatures of 4, 10, 20 and 30 degrees C. Microscopic observations of the survivability and activity of the larvae were conducted every day in all samples. The larvae incubated for 30 days at a temperature of 4 degrees C were viable and non-motile. The longest life span was noted in the case of the larvae incubated in the aerated 1% solution of NaCl at a temperature of 10 degrees C, which also recorded the lowest mobility. The shortest life span was reported for the larvae incubated in the non-aerated 3% solution of NaCl at a temperature of 30 degrees C. The results obtained in this study indicate that the II stage larvae of C. rudolphii may live both in both fresh and salt waters and a significant factor determining their life span is water saturation with oxygen.

Identification of lipids in the cuticle of the parasitic nematode Anisakis simplex and the somatic tissues of the Atlantic cod Gadus morhua.

The main aim of this work was to assign the cuticular lipids identified in a parasitic nematode and to distinguish those originating from its host. The hypothesis that long-chained fatty acids and sterols are imported by the parasite in the absence of certain enzymes was also tested. The organisms (Anisakis simplex and Gadus morhua) were extracted in petroleum ether and dichloromethane. Matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF) was used to identify unknown components, and electrospray ionization mass spectrometry (ESI/MS) to verify recognized groups of lipids. The lipid classes identified in the surface layer were free saturated and unsaturated fatty acids, triacylglycerols, sterols and non-polar sphingolipids (ceramides, sphingoid bases). The most abundant fraction consisted of fatty acids. The predominant saturated acids were tetradecanoic acid in the petroleum ether extract of A. simplex, hexadecanoic acid in the dichloromethane extract of A. simplex, and also the polyunsaturated octadecahexaenoic and octadecatrienoic acids in both extracts of the parasitic nematode. The mass spectrum revealed the presence of fatty acids with different numbers of carbons, and with odd and even numbers of unsaturated bonds. The MALDI-TOF mass spectrum also identified triacylglycerols (TAGs). The dominant short-chain TAGs were CoCoCy:(1), CoCoPg and Bu0:0B:(6). The majority of TAGs were found in the ether and dichloromethane extracts of A. simplex. Sterols were the least common class of lipids found in the nematode extracts; most likely, this is the fraction that is entirely incorporated from the host organism because of the parasite's inability to synthesize them. MALDI-TOF also identified non-polar sphingolipids--ceramides and sphingoid bases. The signals due to N-octanoyl-D-erythro-octasphinganine (m/z 288.3) and N-tetranoyl-D-erythro-tetradecasphinganine (m/z 316.4) were dominant on the mass spectra; quite a large number of short-chain non-polar sphingolipids were also identified.

Mitochondrial DNA of Anisakis simplex s.s. as a potential tool for differentiating populations.

Anisakis simplex s.s. specimens from Gadus morhua, Gadus ogac, Reinhardtius hippoglossoides, Clupea harengus, Micromesistius poutassou, Pleurogrammus monopterygius, and Oncorhynchus nerka, caught in the north Atlantic and Pacific, were examined. Identity of the parasite species was confirmed using a molecular key. All specimens were used for amplifying a part of the non-coding sequence of the AT-rich region, flanked by the nad6-nad4L-trnW-trnE-rrnS-trnS2, and trnN-trnY-nad1 genes. This part of the mtDNA was chosen as a promising fragment, which could yield information regarding population differentiation. The number of samples and their geographical origin was sufficient to compare the 2 regions. The Bayesian analysis provided strong support for a population split into 2 groups, one representing A. simplex s.s. samples from the Pacific, and the other representing all the Atlantic samples. It is highly probable that observed subpopulations were constituted after the connection between the Atlantic and Pacific had been closed and movement between these 2 oceans was prevented.

Anisakid parasites of fishes caught on the African shelf.

Anisakids of Scomber japonicus, Trachyrincus scabrus, Sardina pilchardus, Merluccius polli, Trachurus trachurus, and Hoplostethus cadenati from African shelf are reported. Parasites were extensively studied with respect to their morphology and sequence analysis of the rDNA fragment (containing internal transcribed spacer [ITS]-1, 5.8S subunit and ITS-2); all of them are approximately 1,000 base pairs. Digestion of the amplified region and its sequencing revealed the presence of a sibling species (A. simplex s.s. and A. pegreffii). Still other sequences represented closely related, but not sibling, species, i.e., Anisakis brevispiculata, A. ziphidarum, and A. physeteris; there were also 2 undescribed anisakid species. These species were temporarily described as Anisakis sp. HC-2005 and Anisakis sp. MP-2005 (found, respectively, in Hoplostethus cadenati and Merluccius polli). The study shows that the parasitic fauna of fishes reflects not only the geographic range of anisakid nematodes but also the feeding behavior of the hosts serving as links in the parasites' life cycles.

[Antioxidants of Contracaecum rudolphii (Nematoda)]. / Antyoksydanty Contracaecum rudolphii (Nematoda).

Contracaecum rudolphii is the parasitic nematode of fish-eating birds. In the extracts from female, male and larvae L3 and L4 isolated from the alimentary tracts of black cormorants the activity of five antioxidant enzymes: superoxide dismutase (SOD), glutathione peroxidase (GPX), glutathione transferase (GST), glutathione reductase (GR), catalase (CAT) and the content of ascorbate and total antioxidative status (TAS) were determined. They can be put in order according to the activity growth: GPX, SOD, GST, CAT and GR. The activity of GPX were very low in the nematodes' extracts (1.23-7.67 microU/mg). CAT had higher activity (0.47-0.72 U/mg). The activity of GR was the highest (50.51-69.88 U/mg). SOD activity in the female was higher by ca. 50% than in the male while GST activity was at similar levels. GR and CAT activities were higher by ca. 30% in the male than in the female nematodes. GST and GPX activity and TAS in larvae L3 were significantly lower than in the adult nematodes or in L4 larvae. The activity of GPX, GR and CAT was lower in L4 larvae than in the adult male (p<0.05). The content of ascorbate was almost the same in all stages of parasite development (0.21-0.38 mg/g). The above results indicate differences in antioxidant systems related to both the sex and the developmental stage of C. rudolphii.

[Professor Wincenty Wisniewski's complex experiments about circulation of parasites in the ecosystem of Lake Druzno as a model for activities of the Ichtyoparasitological Section of the Student Scientific Association at the University of Gdansk]. / Kompleksowe badania prof. Wincentego Wisniewskiego nad krazeniem pasozytów w ekosystemie jeziora Druzno jako model dzialan Sekcji Ichtioparazytologicznej Studenckiego Kola Naukowego Biologów Uniwersytetu Gdanskiego.

Druzno Lake is hypertrophic basin located on Zulawy polders (delta of Vistula). Due to the high number of free-living and parasitic species, this lake is unique place for parasitological research. Professor Wisniewski valued Druzno Lake as great area for studying the parasitic species life-cycles. He and his research team lead intensive studies on parasites' circulation in environment. Models compiled by prof. Wisniewski are basal for work of Ichtyoparasitological Section of Student Scientific Association at University of Gdansk.

Experimental infection of Carassius auratus (L., 1758) with the second stage larvae of the nematode Contracaecum rudolphii Hartwich, 1964.

Susceptibility of the goldfish to infection with the newly hatched second stage larvae of Contracaecum rudolphii was investigated under laboratory condition. A week after the larvae had been placed in the fish tank, the autopsied goldfish showed the nematodes in their intestine lumen. The majority of the larvae were dead. In week 2 and 3 of exposure, the larvae were being found exclusively in the intestinal wall; in week 4 and 5, the larvae, in addition to being present in the intestinal wall, were also found in the body cavity. No larvae were found in the fish autopsied in subsequent weeks.

[Contamination of playgrounds in Gdansk city with parasite eggs]. / Skazenie placów zabaw Gdanska jajami pasozytów.

INTRODUCTION: Nematodes of Toxocara genus are common parasites of dogs and cats. These animals are the main source of dangerous zoonoses. The main source of toxocarosis among children are sandpits which are contaminated with dog and cat faeces. We examined the contamination of playgrounds with parasite eggs in Gdatisk city, and frequency of infections of dogs and cats in the area under study. MATERIAL AND METHODS: Samples of sand were taken from a surface of sandpits (to depth about 3 cm). All samples were collected in amount of 100 g. Samples of faeces were taken from various places of the playgrounds. Two methods were applied: flotation and decantation by Fülleborn-Willis in modification by W6jcik. RESULTS: Out of 162 sand samples examined 21 (13%) were positive. Out of 54 faeces samples examined 23 (42.6%) were positive. We observed some differences in the degree of parasite species occurrence. The most dominated were Toxocara spp. (6.2% in sand samples and 11% in faeces samples) and Toxascaris leonina (11% in faeces). Eggs of Uncinaria stenocephala and Ancylostoma canimum, as well as proglotides of Dipylidium caninum were found sporadically.

Hydrolases of Hysterothylacium aduncum (Nematoda).

BACKGROUND: Enzymatic activity is an indicator of an organism's metabolic rate which depends on, i.e., environmental conditions, developmental stage, physiological stage, and sex. The API ZYM test was applied to compare activities of 19 hydrolases of female and male Hysterothylacium aduncum. MATERIAL AND METHODS: Sexually mature nematodes were isolated from eelpout individuals caught in the Gulf of Gdansk. Enzymatic activity of the hydrolases and the protein content was determined in nematode extracts using API ZYM and Bradford's method, respectively. RESULTS: The females and males tested showed a total of 13 enzymes to be active. The males showed additionally the presence of alpha-fucosidase. Acidic and alkaline phosphatases had very high activities in both sexes; short-chain fatty acid esterases, leucine and valine aminopeptidases, alpha-glucosidase, and N-acetylglucosaminidase were highly active. H. aduncum showed no trypsin- and chymotrypsin-specific activities; similarly, no activity of alpha-galactosidase, alpha-mannosidase, and beta-glucuronidase was revealed. Except for lipase (C14), hydrolases were more active in females than in males, which is related to metabolic rate being higher in females due to their reproductive function. CONCLUSION: Comparison of the results obtained with earlier data produced with API ZYM allowed suggesting that the hydrolase pattern may be more affected by habitat in the host than by the taxonomic affiliation of nematode.

Parasite fauna of the eel, Anguilla anguilla (Linnaeus, 1758), from the Polish part of the Vistula Lagoon.

INTRODUCTION: Eel is one of the most valuable commercial fish species of the Vistula Lagoon. For this reason its infection by non-indigenous species of parasites is the subject of the interest of sciencists. MATERIAL AND METHODS: A total of 90 eel specimens caught in the Polish part of the Vistula Lagoon were examined over the period of May-August 2005. The fish were subjected to standard procedures of parasitological examination and parasite identification. The fish were divided into two length classes: smaller and larger than 50 cm. To assess the effects of parasites on fish condition, the Fulton coefficient, expressed with the formula: WF = G x L(-3) x 100, was calculated. RESULTS: The fish were found to be hosts to 17 parasite taxa. The Ciliophora were represented by Trichodinella epizootica (Raabe, 1950); the Myxozoa by Myxidium giardi Cépede, 1906; the Digenea by Bunodera luciopercae (Müller, 1784), Deropristis inflata (Molin, 1859), Diplostomum spp., and Ichthyocotylurus platycephalus (Creplin, 1852); the Cestoda by Bothriocephalus claviceps (Goeze, 1782), Proteocephalus macrocephalus (Creplin, 1815), and Proteocephalus sp.; the Nematoda by Anguillicola crassus Kuwahara, Niimi et Itagaki, 1974, Camallanus lacustris (Zoega, 1776), C. truncatus (Rudolphi, 1814), and Hysterothylacium aduncum (Rudolphi, 1802); the Acanthocephala by Acanthocephalus lucii (Müller, 1776) and Corynosoma strumosum (Rudolphi, 1802); the Hirudinea by Piscicola geometra (Linnaeus, 1761); and the Copepoda by Ergasilus sieboldi Nordmann, 1832. All fishes were infected, and the mean intensity of all parasites was 4.8 inds. The nematode Anguillicola crassus was the most frequent parasite (67.8%, 4.2 inds), represented by all developmental stages, but mostly by adult specimens. The fish condition coefficient was somewhat higher in the eel larger than 50 cm (0.1746) than in those smaller than 50 cm (0.1734); in addition, only Anguillicola crassus-free fish showed a higher condition coefficient (0.1861), compared to the infected specimens (0.1715).