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1.
During a re-assessment of tapeworm collections from wild birds in Slovakia, two Anomotaenia spp. were recovered from the intestine of the little ringed plover Charadrius dubius Scop., 1786. One of them is described as Anomotaenia barusi sp. nov. The new taxon is distinguished from related congeneric species by the different shape and size of the rostellar hooks, the number of testes and the morphology of male and female reproductive organs. The other species was identified as Anomotaenia alata Spassky et Konovalov, 1969. The validity of this species has formerly been questioned because of its striking morphological similarity to the type-species of the genus, A. microrhyncha (Krabbe, 1869), described from the same host, Philomachus pugnax (L.). Present data revealed differences in the number and measurements of the rostellar hooks, the size of the cirrus-sac, the armament of the cirrus and the presence or absence of setae at the polar ends of the inner egg envelope, which supported the validity of A. alata. The finding of A. alata in C. dubius from Slovakia represents a new host and geographical record.  相似文献   

2.
Decorataria decorata (Cram, 1927) is redescribed on the basis of light-microscopy and SEM observations on specimens collected from the stomach of Podiceps cristatus and P. grisegena from Bulgaria. The SEM study revealed the presence of a porebearing field on each pseudolabium and a pair of spines (one dorsal and one ventral) situated between bases of the cordons. The deirids are spine-like and minute. The light-microscopy examination showed the presence of ornamentation situated under the dorsal surface of caudal alae. The occurrence of D. decorata in Bulgaria is a new geographical record.  相似文献   

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The ultrastructure of the spermatozoon of Calliobothrium verticillatum (Cestoda, Tetraphyllidea, Oncobothriidae) parasite of the smoothhound shark, Mustelus mustelus L. (Pisces, Carcharhiniformes), was studied by transmission electron microscopy. This spermatozoon presents five regions characterized by several ultrastructural elements: an apical cone, a crested body, two axonemes of 9 + “1” pattern, electron-dense granules, a nucleus and cortical microtubules. In the present study, three of these features were the subject of a detailed attention. The first is the presence of two axonemes, which confirms that the Tetraphyllidea, Oncobothriidae possess two axonemes whereas the Tetraphyllidea, Phyllobothriidae possess only one axoneme. The second is the presence of one crested body, a criterion homogeneous in the Tetraphyllidea but heterogeneous among the different orders of Cestoda. The third is the number and the disposition of cortical microtubules. These three criteria seem to be interesting for phylogeny.  相似文献   

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In this paper Steringotrema microacetabularis (Suriano et Martorelli, 1983) is redescribed and transferred to Bacciger Nicoll, 1924 in the Faustulidae Poche, 1926 based on newly collected material from the type-host, Paralichthys orbignyanus Valenciennes, 1839 and the type-locality, Mar Chiquita coastal lagoon, Buenos Aires Province, Argentina. A careful re-examination of the new specimens shows that some anatomical characteristics were ignored or incompletely described by the previous authors and they are included herein. The species is tentatively transferred to Bacciger with which it appears to have closest affinity. Despite the anatomical differences detailed in this paper, confirmation of this proposal must await further work, including molecular studies.  相似文献   

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The glands in the pseudoscolex of the echinophallid cestode Paraechinophallus japonicus (Bothriocephalidea), a parasite of the bathypelagic fish Psenopsis anomala (Perciformes, Centrolophidae), were studied using scanning and transmission electron microscopy. Two types of glands, with different morphological types of secretory granules and mechanisms for discharging their glandular secretion, were observed. Both types of gland cell bodies are localized in the parenchyma of the pseudoscolex. The syncytial glands of type I are characterized by the production of small (all ∼0.25 μm in diameter), rounded, dense secretory granules which pass though thin projections into the distal tegumental layer of the pseudoscolex. This type of gland has a unique method of discharging its secretory granules, which we call tumulogenesis. The elimination of the secretory products is realized by an encroachment of the basement membrane and underlying tegumental muscles into the surface region of the distal cytoplasm of the tegument, resulting in the formation of a ‘glandular stalk’ above which develops a superficial glandular tumulus. In the region of the glandular material of the tumulus, the basement membrane of the stalk forms a dilation, and the appearance of a membrane-bound area serves to separate the tumulus from the distal cytoplasm of the tegument. Unicellular glands of type II are characterized by large granules (0.4–0.9 μm in diameter), the presence of peripheral microtubules in the terminal region of their ducts and an eccrine mechanism for the discharge of their secretory granules. A comparative analysis of the distribution and morphology of the types of scolex glands among members of the different families of the ‘Pseudophyllidea’ (currently believed to represent two distinct orders, Bothriocephalidea and Diphyllobothriidea) is presented.  相似文献   

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Genomic in situ hybridization (GISH) was used to make a detailed study of chromosome pairing at metaphase I (MI) of meiosis in six F(1) hybrid plants of the allotetraploid Festuca pratensis x Lolium perenne (2n = 4x = 28; genomic constitution FpFpLpLp). The mean chromosome configurations for all hybrids analysed were 1.13 univalents + 11.51 bivalents + 0.32 trivalents + 0.72 quadrivalents, and the mean chiasma frequency was 21.96 per cell. GISH showed that pairing was predominantly intragenomic, with mean numbers of L. perenne (Lp/Lp) and F. pratensis (Fp/Fp) bivalents being virtually equal at 5.41 and 5.48 per cell, respectively. Intergenomic pairing between Lolium and Festuca chromosomes was observed in 33.3% of Lp/Fp bivalents (0.62 per cell), in 79.7% of trivalents - Lp/Lp/Fp and Lp/Fp/Fp (0.25 per cell), and in 98.4% of quadrivalents - Lp/Lp/Fp/Fp and Lp/Lp/Lp/Fp (0.71 per cell). About 4.0% of the total chromosome complement analysed remained as univalents, an average 0.68 Lp and 0.45 Fp univalents per cell. It is evident that in these hybrids there is opportunity for recombination to take place between the two component genomes, albeit at a low level, and this is discussed in the context of compromising the stability of Festulolium hybrid cultivars and accounting for the drift in the balance of the genomes over generations. We speculate that genotypic differences between hybrids could permit selection for pairing control, and that preferences for homologous versus homoeologous centromeres in their spindle attachments and movement to the poles at anaphase I could form the basis of a mechanism underlying genome drift.  相似文献   

13.
The parasite Trichomonas vaginalis causes one of the most common non-viral sexually transmitted infections in humans. Mycoplasmas are frequently found with trichomonads but the consequences of this association are not yet known. In the present study, the effects of T. vaginalis harboring M. hominis on human vaginal epithelial cells and on MDCK cells are described. The results were analyzed by light, scanning and transmission electron microscopy, as well as using cell viability assays. There was an increase in the cytopathic effects on the epithelial cells infected with T. vaginalis associated with M. hominis compared to T. vaginalis alone. The epithelial cells exhibited an increase in the intercellular spaces, a lesser viability, and increased destruction provoked by the infected T. vaginalis. In addition, the trichomonads presented a higher amoeboid transformation rate and an intense phagocytic activity, characteristics of higher virulence behavior.  相似文献   

14.
To evaluate the use of c-erbB-2 oncogene and p21 WAF1/CIP1 suppressor gene products as the prognosis markers for canine mammary tumors, expression of these gene products were examined immunohistochemically using tumor tissues and clinical data from 96 dogs with malignant mammary tumors. Semiquantitative data was compared with histopathological grades, proliferating cell nuclear antigen (PCNA)-positive index, and clinicopathological matters. The expression c-erbB-2 protein was found in the cellular membrane and cytoplasm of neoplastic epithelial cells, and the positive index had no significant relation to the histopathological features and PCNA-positive index, except for the individual age of affected dogs (P < 0.05). The product of p21 WAF1/CIP1 was mostly found in cytoplasm and occasionally in the nucleus of neoplastic cells. The quantitative data had significant association to the malignancy grade and size of tumors (P < 0.05). However, that had no significant relationship to the PCNA-positive index. The present study concluded that both gene products could not apply as the direct markers to evaluate the prognosis of canine mammary tumors. The detection of c-erbB-2 product may be partly beneficial to the differential diagnosis of epithelial type of mammary cancer. The use of p21 WAF1/CIP1 product in prognosis of canine mammary cancer needs further investigation.  相似文献   

15.
Sand lizards (Lacerta agilis) were trapped and examined for ticks from May to September in 2002 and 2003 in Northeastern Poland. A total of 233 Ixodes ricinus (L.) ticks (76 larvae and 157 nymphs) was found on 31 of 235 captured lizards (13.2%). The tick infestation is relatively low compared to that of mammals and passerine birds from the same area (Siński et al. 2006, Gryczyńska et al. 2002). Tick infestation depended on the month of capture, being the highest in spring. In autumn no ticks were recorded on any of the captured lizards. The oldest lizards carried the highest number of ticks but no differences related to sex of the host were found. All the collected ticks were analysed by PCR for the presence of Borrelia burgdorferi sensu lato, the etiological agents of Lyme disease. Spirochetes were detected in 11 out of 233 (4.7%) ticks tested. Genetic analysis confirmed that the spirochetes are members of the Borrelia afzelii, B. garinii and B. burgdorferi sensu stricto genospecies. Mixed infection were not detected. The prevalence of infection was analysed in relation to months of the capture, age and sex of the lizards, but differences were not statistically significant. The obtained results suggest that lizards are probably not B. burgdorferi reservoirs, but further studies are required to confirm this.  相似文献   

16.
We propose to name as Lamellodiscus theroni sp. nov., the gill parasite of Diplodus puntazzo (Cetti) that was reported by Euzet (1984) as L. ergensi Euzet and Oliver, 1966 in Kerkennah Island (Tunisia). L. theroni sp. nov. was also found specific to D. puntazzo in Algiers Bay (Algeria) and in Gulf of Lion (France). The host specificity of various Lamellodiscus species on D. puntazzo is briefly discussed. Within Lamellodiscus, L. theroni belongs to the “ignoratus” group characterized by a “lyre” shaped male copulatory organ and to the “ergensi” subgroup, characterized by a complex morphology of the haptoral dorsal bars. L. theroni differs from the five other species of this subgroup (L. ergensi, L. kechemirae, L. tomentosus, L. sanfilippoi, L. baeri) by the morphology and the size of the haptoral dorsal bar. L. theroni, as well as, L. hilii, L. bidens, L. impervius, was only reported on the sparid Diplodus puntazzo. These parasite species are all considered as oioxenic.  相似文献   

17.
Biofilm formation is an important part of the bacterial life cycle. Biofilms provide bacterial resistance to external stresses and protozoan grazing. Biofilm formation by the wild type of B. cenocepacia strain 370 in the presence of the free-living ciliate Tetrahymena pyriformis was studied. T. pyriformis grazed on planktonic bacteria and reduced the planktonic bacterial subpopulation while it noticeably stimulated biofilm formation. When cultivated alone, T. pyriformis did not form visible biofilms. Confocal laser scanning microscopy was used to demonstrate the inclusion and further destruction of protozoan cells within the biofilms formed by the bacteria. The destruction of protozoan cells was accompanied by the exit of bacteria from vacuoles and intracytoplasmic multiplication; changes in the form of protozoan cells; the demolition of internal structures; and the visual exit of the cytoplasmic content from destructing cells. Microcolonies of a characteristic round shape were revealed in the biofilms formed by B. cenocepacia in the presence of T. pyriformis. These structures were absent in the biofilms formed by B. cenocepacia alone. Insertion of protozoan cells within biofilms seems to be a driving force that promotes biofilm proliferation and influences their structure. The mortality of protozoan cells in the biofilms caused a decrease in the T. pyriformis population under conditions advantageous to B. cenocepacia biofilm formation. The mutant B. cenocepacia strain Bcb-1, which is unable to form biofilms, was isolated by plasposon mutagenesis. In contrast to the parental strain, the cocultivation with Bcb-1 bacteria improved the growth of T. pyriformis. A mutation was mapped in the ompR gene. The text was submitted by the authors in English.  相似文献   

18.
Zygosaccharomyces rouxii is a hemiascomycetous yeast known for its high osmotolerance, the basis of which still remains unknown. By exploring the Génolevures I database, four Z. rouxii fragments homologous to Saccharomyces cerevisiae centromeres were identified. Two of them were subjected to further analysis. Their function as centromeres in Z. rouxii was proved, and they were localized to Z. rouxii chromosomes II and VII, respectively. The species-specificity of centromeres was observed; plasmids with a Z. rouxii centromere were not recognized as centromeric in S. cerevisiae, and a S. cerevisiae centromere did not function as a centromere in Z. rouxii. Constructed plasmids bearing Z. rouxii centromeres serve as the first specific centromeric plasmids, and thus contribute to the so-far limited set of genetic tools needed to study the Z. rouxii specific features.  相似文献   

19.
Plasmodium, Haemoproteus, and leukocytozoon are the most important hematozoa in birds, which have been reported in different areas of the world. The present study was undertaken to find which blood protozoans exist in indigenous chickens in Shiraz, southern Iran and to evaluate hematological parameters in birds infected with hematozoas. Plasmodium and Aegyptianella were the two parasites found in 740 blood samples examined from indigenous chickens of which 29 (3.91%) were positive for Aegyptianella pullorum, 106 (14.32%) for Plasmodium gallinaceum, and 12 (1.62%) for A. pullorum and Plasmodium gallinaceum together. There was no significant difference between hematological parameters of non-infected and naturally infected chickens with Plasmodium gallinaceum, A. pullorum, and both (P > 0.05). Low infection of indigenous chickens with A. pullorum, Plasmodium gallinaceum, and both had no significant effects on hematological parameters (P > 0.05), which is probably due to low parasitemia rate and immunity against these two parasites.  相似文献   

20.
Ultrastructural study of spermiogenesis and of the spermatozoon of Carmyerius endopapillatus has enabled to describe some characteristics of this digenea. The intercentriolar body situated between the two striated roots and the two centrioles, presents a symmetric organization. Both external bands of this intercentriolar body are made up of a row of granules. During spermiogenesis, a flagellar rotation of 90° is described. The old spermatid does not present external ornamentations. The spermatozoon is characterized, in its anterior region, by the presence of a lateral expansion exhibiting one spinelike body. In C. endopapillatus, external ornamentations are localized only at the level where the lateral expansion appears. The posterior extremity of spermatozoon exhibits a nucleus surrounded by a plasmic membrane lacking microtubules, but presenting a small lateral expansion. This is the first species of Gastrothylacidae family studied by transmission electron microscopy.  相似文献   

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