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2. Bacillus Calmette-Guérin-inoculation at different time points influences the outcome of C57BL/6 mice infected with Plasmodium chabaudi chabaudi AS
- Creator:
- Cao, Dong-Hua, Wang, Ji-Chun, Liu, Jun, Du, Yun-Ting, Cui, Li-Wang, and Cao, Ya-Ming
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- imunita (lékařství), parazitologie, immunity, parasitology, protective immunity, murine malarial parasite, BCG, co-infection, 2, and 59
- Language:
- English
- Description:
- Bacillus Calmette-Guérin (BCG) is an attenuated Mycobacterium tuberculosis vaccine. We performed a series of co-infection experiments with BCG-Plasmodium chabaudi chabaudi Landau, 1965 AS using C57BL/6 mice to analyse whether BCG can affect the development of protective immunity to infection with Plasmodium spp. and the mechanism of this protection. We divided mice into four groups: BCG-inoculation 4 weeks prior to P. c. chabaudi AS infection (B-4w-Pc); simultaneous BCG-inoculation and P. c. chabaudi AS infection (Pc+B); BCG-inoculation 3 days post P. c. chabaudi AS (Pc-3-B) infection; and mono-P. c. chabaudi AS infection as control (Pc). The parasitemia level in the B-4w-Pc group was noticeably higher than control group at 6-19 days post infection (dpi). Compared with the control group, the proportion of CD4+CD69+ T cells was significantly reduced 5, 8 and 12 dpi, but the proportion of CD4+CD25+Foxp3+ Tregs was significantly increased in the B-4w-Pc group on 5 and 8 dpi. The B-4w-Pc group also demonstrated reduced levels of IFN-γ and TNF-α on 5 and 8 dpi and significantly elevated level of IL-10 on 12 dpi. There were significantly fewer mDCs (CD11c+CD11b+) and pDCs (CD11c+B220+) in the B-4w-Pc group than the control group at all the time points post infection and the expression of MHC II was noticeably reduced on day 8 pi. Our findings confirmed that BCG inoculation prior to Plasmodium infection resulted in excessive activation and proliferation of Tregs and upregulation of anti-inflammatory mediators, which inhibited establishment of a Th1-dominant immune response during the early stages of Plasmodium infection by inhibiting dendritive cells response. BCG inoculation prior to P. c. chabaudi AS infection may contribute to overgrowth of parasites as well as mortality in mice., Dong-Hua Cao, Ji-Chun Wang, Jun Liu, Yun-Ting Du, Li-Wang Cui, Ya-Ming Cao., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3. Increased sialylation as a phenomenon in accommodation of the parasitic nematode Trichinella spiralis (Owen, 1835) in skeletal muscle fibres
- Creator:
- Milcheva, Rositsa, Ivanov, Dimitar, Iliev, Ivan, Russev, Russy, Petkova, Svetlozara, and Pavel Babál
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitologie, parasitology, glycosylation, sialic acid, nurse cell, 2, and 59
- Language:
- English
- Description:
- The biology of sialic acids has been an object of interest in many models of acquired and inherited skeletal muscle pathology. The present study focuses on the sialylation changes in mouse skeletal muscle after invasion by the parasitic nematode Trichinella spiralis (Owen, 1835). Asynchronous infection with T. spiralis was induced in mice that were sacrificed at different time points of the muscle phase of the disease. The amounts of free sialic acid, sialylated glycoproteins and total sialyltransferase activity were quantified. Histochemistry with lectins specific for sialic acid was performed in order to localise distribution of sialylated glycoconjugates and to clarify the type of linkage of the sialic acid residues on the carbohydrate chains. Elevated intracellular accumulation of α-2,3- and α-2,6-sialylated glycoconjugates was found only within the affected sarcoplasm of muscle fibres invaded by the parasite. The levels of free and protein-bound sialic acid were increased and the total sialyltransferase activity was also elevated in the skeletal muscle tissue of animals with trichinellosis. We suggest that the biological significance of this phenomenon might be associated with securing integrity of the newly formed nurse cell within the surrounding healthy skeletal muscle tissue. The increased sialylation might inhibit the affected muscle cell contractility through decreased membrane ion gating, helping the parasite accommodation process., Rositsa Milcheva, Dimitar Ivanov, Ivan Iliev, Russy Russev, Svetlozara Petkova, Pavel Babál., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4. Life cycle of Hepatozoon affluomaloti sp. n. (Apicomplexa: Haemogregarinidae) in crag lizards (Sauria: Cordylidae) and in culicine mosquitoes from South Africa
- Creator:
- As, Johann Van, Davies, Angela J, and Smit, Nico J
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitologie, parasitology, gamonts, merogonic stage, oocysts, sporocysts, sporozoites, transmission, 2, and 59
- Language:
- English
- Description:
- A new haemogregarine species Hepatozoon affluomaloti sp. n. is described from erythrocytes in the peripheral blood of crag lizards Pseudocordylus melanotus (Smith) and Pseudocordylus subviridis (Smith) (Sauria: Cordylidae) from mountainous regions in the Eastern Free State, South Africa. This species can be distinguished from all other congeners based on its large size, staining properties and life cycle development in its vector, Culex (Afroculex) lineata (Theobald) (Diptera: Culicidae). Mature gamonts stain mostly uniformly pinkish-purple with Giemsa, sometimes containing darker azurophilic granules anterior and posterior to the nucleus. The reflexed posterior extremity of the gamont stage sometimes stains slightly deeper purple and the nucleus is dense and placed in the posterior third of the parasite body. Merogonic stages of this haemogregarine occur in the liver tissues of P. melanotus with dizoic meronts. Macromeronts contains 2-7 macromerozoites and micromeronts contains 9-24 micromerozoites. Sporogonic developmental stages found in the proposed final host and vector, C. lineata, include large oocysts, measuring 54 × 48 µm on average. Sporulating oocysts with 8 nuclei are present in mosquitoes 6-7 days post-feeding on infected lizards. Sporocysts with mature sporozoites measure 31.0 × 21.8 µm on average and each contains 2-8 large sporozoites. It is suggested that transmission of infective sporozoites is achieved through predation of lizards on mosquitoes., Johann Van As, Angela J. Davies, Nico J. Smit., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
5. Pentastome assemblages of the Nile crocodile, Crocodylus niloticus Laurenti (Reptilia: Crocodylidae), in the Kruger National Park, South Africa
- Creator:
- Junker, Kerstin, Calitz, Frikkie, Govender, Danny, Boris Ronal'dovič Krasnov, and Boomker, Joop
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitologie, parasitology, Alofia, Leiperia, Sebekia, Pentastomida, abundance, prevalence, species richness, crocodilians, 2, and 59
- Language:
- English
- Description:
- Thirty-two specimens of the Nile crocodile, Crocodylus niloticus Laurenti (Reptilia: Crocodylidae), from the Kruger National Park, South Africa, and its vicinity were examined for pentastomid parasites during 1995 to 1999 and 2010 to 2011. Pentastomid parasites occurred throughout the year and were widespread in the study area with an overall prevalence of 97% and an overall mean abundance of 23.4 (0-81). Pentastome assemblages comprised six species in three sebekid genera: Alofia nilotici Riley et Huchzermeyer, 1995, A. simpsoni Riley, 1994, Leiperia cincinnalis Sambon, 1922, Sebekia cesarisi Giglioli in Sambon, 1922, S. minor (Wedl, 1861) and S. okavangoensis Riley et Huchzermeyer, 1995. The possible influence of host age, gender and geographic location (river system) on pentastome prevalence, abundance and species richness was investigated. Generally, neither host age, gender nor locality did affect infracommunities, likely because all hosts examined were adult or subadult and displayed comparable foraging behaviour, resulting in similar exposure pathways to fish intermediate hosts. Additionally, the longevity of pentastomids would contribute to accumulative infections as hosts mature. Structuring of pentastome assemblages was observed in as far as S. minor was the dominant species based on overall prevalence and abundance, followed by the equally common species S. cesarisi and L. cincinnalis. With an overall prevalence ranging from 34% to 41% and relatively low abundances, A. nilotici, A. simpsoni and S. okavangoensis form the rarer component of pentastome communities., Kerstin Junker, Frikkie Calitz, Danny Govender, Boris R. Krasnov, Joop Boomker., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public