« Previous |
1 - 10 of 11
|
Next »
Number of results to display per page
Search Results
2. Cloning, expression and characterisation of a cysteine protease from Trichinella spiralis
- Creator:
- Song, Yan Yan, Wang, Li Ang, Ren, Hua Na, Qi, Xin, Sun, Ge Ge, Liu, Ruo Dan, Jiang, Peng, Zhang, Xi, Cui, Jing, and Wang, Zhong Quan
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitologie, parasitology, Trichinellosis, cysteine protease, invasion, development, 2, and 59
- Language:
- English
- Description:
- Cysteine protease is a superfamily of widespread proteolytic enzymes and plays a major role in larval invasion, migration, exsheathing, survival and immune evasion in parasites. In the present study, the gene coding cysteine proteinase of the nematode Trichinella spiralis (Owen, 1835) was cloned into pQE-80L and subsequently expressed in E. coli JM109. The rTsCP was purified and its antigenicity was identified by Western blot and ELISA. Using anti-rTsCP serum the native TsCP was identified in muscle larval crude proteins. The results of quantitative real-time PCR and immunofluorescence test demonstrated that the TsCP was expressed in all stages of T. spiralis and located mainly in cuticle, stichosome and reproductive organs. The immunisation of mice with rTsCP elicited Th2-predominant immune responses. Anti-rTsCP antibodies could partially inhibit the in vitro larval invasion of intestinal epithelial cells and kill the newborn larvae by an antibody-dependent cell-mediated dose-dependent cytotoxicity. The vaccinated mice exhibited a 54% reduction of adults and a 33% reduction of muscle larvae following challenge infection. The results suggested that the TsCP might be an indispensable protein in Trichinella invasion, development and survival of T. spiralis in hosts, and could be a potential vaccine target against infection., Yan Yan Song, Li Ang Wang, Hua Na Ren, Xin Qi, Ge Ge Sun, Ruo Dan Liu, Peng Jiang, Xi Zhang, Jing Cui, Zhong Quan Wang., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3. Experimental microsporidiosis in immunocompetent immunodeficient mice and monkeys
- Creator:
- Didier, E.S., Varner, P.W., Didier, P.J., Aldras, A.M., Millichamp, N.J., Murphey-Corb, M., Bohm, R., and Shadduck, J.A.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Microsporidia, AIDS, opportunistic infection, Nosema, Encephalitozoon, encephaiitozoonosis, and microsporidiosis
- Language:
- English
- Description:
- Microsporidia cause opportunistic infections in AIDS patients and commonly infect laboratory animals, as well. Euthymie C57B1/6 mice experimentally infected with intraperitoneal injections of lxlO6 Encephalitozoon cuniculi Levaditi, Nicolau et Schoen, 1923, Encephalitozoon hellem Didier et al., 1991, or Nosema comeum Shadduck et al., 1990 displayed no clinical signs of disease. Athymic mice, however, developed ascites and died 8-16 days after inoculation with N. comeum, 21-25 days after inoculation with E. cuniculi, and 34-37 days after inoculation with E. hellem. All athymic mice displayed hepatomegaly, dilated intestine and accumulation of ascites fluid. Granulomatous lesions were primarily located in the liver, lung, pancreas, spleen, and on serosal surfaces of abdominal organs.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Fantastično, váhání a víra
- Creator:
- Zuska, Vlastimil
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Czech and English
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. New information on morphology and molecular data of camallanid nematodes parasitising Xenopus laevis (Anura: Pipidae) in South Africa
- Creator:
- Svitin, Roman, Schoeman, Anneke L, and Preez, Louis H. du
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitické organismy, hlístice, parasitic organisms, Nematodes, African clawed frog, parasites, Camallanidae, Camallanus, C. kaapstaadi, C. xenopodis, Batrachocamallanus, B. slomei, Procamallanus, 2, and 59
- Language:
- English
- Description:
- Three species of nematodes from the Camallanidae that are known to infect Xenopus laevis Daudin (Anura: Pipidae) were collected from several localities across South Africa. New data on morphology, partial 28S and cox1 genes, infection levels and distribution are presented herein. The most common species, Batrachocamallanus slomei Southwell et Kirshner, 1937, from the stomach and less often oesophagus, was found in eight localities. Camallanus kaapstaadi Southwell et Kirshner, 1937, also from the oesophagus, was found in two localities and C. xenopodis Jackson et Tinsley, 1995, from the intestine, at a single locality. New localities for both C. kaapstaadi and C. xenopodis provide a geographical range extension. Males of C. xenopodis are described for the first time herein. The existence of a left spicule in the males of both the species of Camallanus Railliet and Henry, 1915 is confirmed and measurements are provided. Although C. xenopodis is distinguished from C. mazabukae Kung, 1948 in the present study, we suggest greater sampling effort in other African amphibians to confirm the species status of the latter taxon. Finally, the new molecular data showed distant relationships between collected species of Camallanus and species parasitising fish and freshwater turtles., Roman Svitin, Anneke L. Schoeman, Louis H. du Preez., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
6. Reproductive innovation and the recognition of a new genus within the Polystomatidae (Monogenea) infecting chelonian vertebrates
- Creator:
- Tinsley, Richard C
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- rozmnožování (biologie), evoluce (biologie), děloha, reproduction, evolution (biology), uterus, Polystomoides, Uteropolystomoides nelsoni, oötype, helminth egg production, key, 2, and 59
- Language:
- English
- Description:
- Polystomatid monogeneans have a wide diversity of life cycles correlated with the varied ecology and behaviour of their aquatic vertebrate hosts. Typically, transmission involves a swimming infective larva but most hosts are amphibious and invasion is interrupted when hosts leave water. A key life cycle adaptation involves a uterus that, in the most specialised cases, may contain several hundred fully-developed larvae prepared for instant host-to-host transmission. By contrast, one subfamily of the Polystomatidae - the Polystomoidinae, specific to chelonians (freshwater turtles) - has a simplified reproductive system without a uterus. Recently, Polystomoides nelsoni Du Preez et Van Rooyen, 2015 has been described with a uterus containing multiple eggs. The present study explores the exceptional interest of this parasite - for the functional biology of egg production, for the evolution of a reproductive system unique amongst ca 60 species in the subfamily, and for systematic relationships. A new genus is proposed, Uteropolystomoides gen. n., separate from the four currently-recognised genera Polystomoides Ward, 1917, Uropolystomoides Tinsley et Tinsley, 2016, Neopolystoma Price, 1939 and Polystomoidella Price, 1939 which lack a uterus. In addition, U. nelsoni (Du Preez et Van Rooyen, 2015) comb. n. has a suite of distinctive copulatory stuctures: a massive genital bulb with an exceptionally large number of very long genital spines and hyper-development of the vaginal openings. These characters set U. nelsoni apart from all other polystomoidines worldwide except Polystomoides multifalx Stunkard, 1924 and P. stunkardi Harwood, 1931. Missing data for these latter species preclude definitive assessment of inter-relationships but the distinguishing characters of U. nelsoni, especially the unique occurrence of the uterus, suggest a novel evolutionary pathway isolated from other lineages of polystomatids infecting chelonians., Richard C. Tinsley., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7. Scolex morphology of monozoic tapeworms (Caryophyllidea) from the Nearctic Region: taxonomic and evolutionary implications
- Creator:
- Oros, Mikuláš, Uhrovič, Dalibor, Choudhury, Anindo, Mackiewicz, John S, and Tomáš Scholz
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- tasemnice, ryby, srovnávací mytologie, skenovací elektronová mikroskopie, tapeworms, fishes, comparative mythology, scanning electron microscopy, Catostomidae, Cestoda, scolex terminology, identification, 2, and 59
- Language:
- English
- Description:
- A comparative study of the scoleces of monozoic tapeworms (Cestoda: Caryophyllidea), parasites of catostomid and cyprinid fishes (Teleostei: Cypriniformes) in the Nearctic Region, was carried out using light and scanning electron microscopy. Scoleces of 22 genera of North American caryophyllideans were characterised and their importance for taxonomy, classification and phylogenetic studies was critically reviewed. Nearctic genera exhibit a much higher variation in the shape and form of scoleces compared with taxa in other biogeographical regions. The following basic scolex types can be recognised in Nearctic caryophyllideans: monobothriate (Promonobothrium Mackiewicz, 1968), loculotruncate (Promonobothrium, Dieffluvium Williams, 1978), bothrioloculodiscate (Archigetes Leuckart, 1878, Janiszewskella Mackiewicz et Deutsch, 1976, Penarchigetes Mackiewicz, 1969, Pseudoglaridacris Oros, Uhrovič et Scholz, 2018), fixomegabothriate (Capingens Hunter, 1927), bulbate and bulboacuminate (Atractolytocestus Anthony, 1958), cuneiloculate (Hypocaryophyllaeus Hunter, 1927, Rowardleus Mackiewicz et Deutsch, 1976, Spartoides Hunter, 1929), biacetabulate, bulboloculate, bothrioloculodiscate (Biacetabulum Hunter, 1927), tholate (Hunterella Mackiewicz et McCrae, 1962), cuneifimbriate (Khawia Hsü, 1935), cuneiform (Calentinella Mackiewicz, 1974, Caryophyllaeides Nybelin, 1922, Edlintonia Mackiewicz, 1970), hastate (Pseudolytocestus Hunter, 1929), loculotholate (Bialovarium Fischthal, 1953, Pliovitellaria Fischthal, 1951), and cuneiformoloculate (Glaridacris Cooper, 1920, Isoglaridacris Mackiewicz, 1965). The same type of scolex may be shared by species of different genera or families and species of the same genus can have a scolex of conspicuously different morphology, e.g. in Promonobothrium. Scolex morphology may be therefore of limited use in generic designation., Mikuláš Oros, Dalibor Uhrovič, Anindo Choudhury, John S. Mackiewicz and Tomáš Scholz., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
8. The molecular phylogeny of the digenean family Opecoelidae Ozaki, 1925 and the value of morphological characters, with the erection of a new subfamily
- Creator:
- Rodney Alan Bray, Cribb, Thomas H, Littlewood, D. Timothy J, and Waeschenbach, Andrea
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- fylogeneze, motolice, phylogeny, Trematoda, Digenea, Opecoelinae, Plagioporinae, Stenakrinae, Opecoelininae, rDNA sequence, Helicometrinae, 2, and 59
- Language:
- English
- Description:
- Large and small rDNA sequences of 41 species of the family Opecoelidae are utilised to produce phylogenetic inference trees, using brachycladioids and lepocreadioids as outgroups. Sequences were newly generated for 13 species. The resulting Bayesian trees show a monophyletic Opecoelidae. The earliest divergent group is the Stenakrinae, based on two species which are not of the type-genus. The next well-supported clade to diverge is constituted of three species of Helicometra Odhner, 1902. Based on this tree and the characters of the egg and uterus, a new subfamily, the Helicometrinae, is erected and defined to include the genera Helicometra, Helicometrina Linton, 1910 and Neohelicometra Siddiqi et Cable, 1960. The subfamily Opecoelinae is found to be monophyletic, but the Plagioporinae is paraphyletic. The single representative of the Opecoelininae (not of the type genus) is nested within a group of deep-sea 'plagioporines'. The two representatives of the Opistholebetidae are embedded within a group of shallow-water 'plagioporine' species. The Opistholebetidae is reduced to subfamily status pro tem as its morphological and biological characteristics are distinctive. This implies that as opecoelid systematics develops with more molecular evidence, several further subfamilies will be recognised. Many of the morphological characters were found to be homoplasious, but the characters defining the Helicometrinae and Opecoelinae, such as filamented eggs, reduced cirrus-sac and uterine seminal receptacle, are closely correlated with the inferred phylogeny., Rodney A. Bray, Thomas H. Cribb, D. Timothy J. Littlewood, Andrea Waeschenbach., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
9. Toxoplasma gondii seropositivity and substance use in US adults
- Creator:
- Berrett, Andrew N, Gale, Shawn D, Erickson, Lance D, Thacker, Evan L, Brown, Bruce L, and Hedges, Dawson W
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- toxoplazmóza, tabák, alkoholy, marihuana, kokain, heroin, pervitin, užívání drog, toxoplasmosis, tobacco, alcohols, marijuana, cocaine, methamphetamine, drug abuse, 2, and 59
- Language:
- English
- Description:
- The intracellular parasite Toxoplasma gondii (Nicolle et Manceaux, 1908) infects humans resulting in acute toxoplasmosis, an infection that in immunocompetent people is typically mild but results in persistent latent toxoplasmosis. In that T. gondii appears to affect dopamine synthesis and because addicting drugs affect midbrain dopamine transmission, latent toxoplasmosis could influence substance use. Using both the third and continuous National Health and Nutrition Examination Surveys from the US Centers for Disease Control and Prevention, we used logistic regression to test for associations between T. gondii seropositivity and subject self-report of having ever used tobacco, alcohol, marijuana, cocaine, heroin, or methamphetamine. In the third NHANES dataset, which included data for tobacco, alcohol, marijuana and cocaine, T. gondii seropositivity was associated with a reduced likelihood of self-reported marijuana (OR = 0.71 [95% CI: 0.58; 0.87]; p = 0.001) and cocaine use (OR = 0.72 [95% CI: 0.56; 0.91]; p = 0.006). In the continuous National Health and Nutrition Examination Surveys dataset, which included data for all six substances, T. gondii seropositivity was associated with a reduced likelihood of self-reported tobacco (OR = 0.87 [95% CI: 0.76; 1.00]; p = 0.044), marijuana (OR = 0.60 [95% CI: 0.50; 0.72]; p < 0.001), heroin (OR = 0.60 [95% CI: 0.42; 0.85]; p = 0.005) and methamphetamine use (OR = 0.54 [95% CI: 0.38; 0.77]; p = 0.001). We observed interactions between sex and T. gondii seropositivity in the prediction of self-reported use of tobacco and alcohol. Further, T. gondii seropositivity appeared to remove the protective effect of education and economic status against self-reported cigarette smoking. These findings suggest that T. gondii seropositivity may be inversely associated with some but not all types of substance use in US adults., Andrew N. Berrett, Shawn D. Gale, Lance D. Erickson, Evan L. Thacker, Bruce L. Brown, Dawson W. Hedges., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10. Two new species of Hepatozoon (Apicomplexa: Hepatozoidae) parasitising species of Philothamnus (Ophidia: Colubridae) from South Africa
- Creator:
- Cook, Courtney Antonia, Netherlands, Edward Charles, As, Johann van, and Smit, Nico Jacobus
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- hadi, fylogeneze, snakes, phylogeny, serpents, haemogregarines, adeleorid taxonomy, 18S rDNA, haemoparasites, 2, and 59
- Language:
- English
- Description:
- To date, only a few species of Hepatozoon Miller, 1908 have been described from amphibians and reptiles of South Africa, including two species from anuran hosts, three from saurians, one from chelonians, and two from ophidians. Hepatozoon bitis (Fantham, 1925) and Hepatozoon refringens (Sambon et Seligmann, 1907), parasitising Bitis arientans (Merrem) and Pseudoaspis cana (Linnaeus), respectively, were described in the early 1900s and since then there have been no further species of Hepatozoon described from snakes in South Africa. Blood smears, used in peripheral blood haemogregarine stage morphometrics, and whole blood used in molecular characterisation of haemogregarines were collected from the caudal vein of six snakes of three species, namely Philothamnus hoplogaster (Günther), Philothamnus semivariegatus (Smith) and Philothamnus natalensis natalensis (Smith). For comparison, a comprehensive table summarising available information on species of Hepatozoon from African snakes is presented. Haemogregarines found infecting the snakes from the present study were morphologically and molecularly different from any previously described from Africa and are thus here described as Hepatozoon angeladaviesae sp. n. and Hepatozoon cecilhoarei sp. n. Both haemogregarine species were observed to cause considerable dehaemoglobinisation of the host cell, in case of infection with H. angeladaviesae resulting in a characteristic peripheral undulation of the host cell membrane and karyorrhexis. To the authors' knowledge, these are the first haemogregarines parasitising snakes of the genus Philothamnus Smith described using both morphological and molecular characteristics in Africa., Courtney Antonia Cook, Edward Charles Netherlands, Johann van As, Nico Jacobus Smit., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public