Search results for " parasite"
showing 10 items of 133 documents
Protein sorting in Plasmodium falciparum-infected red blood cells permeabilized with the pore-forming protein streptolysin O
1996
Plasmodium falciparum is an intracellular parasite of human red blood cells (RBCs). Like many other intracellular parasites, P. falciparum resides and develops within a parasitophorous vacuole which is bound by a membrane that separates the host cell cytoplasm from the parasite surface. Some parasite proteins are secreted into the vacuolar space and others are secreted, by an as yet poorly defined pathway, into the RBC cytosol. The transport of proteins from the parasite has been followed mainly using morphological methods. In search of an experimental system that would allow (i) dissection of the individual steps involved in transport from the parasite surface into the RBC cytosol, and (ii…
Differentiation of Type 1 ILCs from a Common Progenitor to All Helper-like Innate Lymphoid Cell Lineages
2014
SummaryInnate lymphoid cells (ILCs) are a recently recognized group of lymphocytes that have important functions in protecting epithelial barriers against infections and in maintaining organ homeostasis. ILCs have been categorized into three distinct groups, transcriptional circuitry and effector functions of which strikingly resemble the various T helper cell subsets. Here, we identify a common, Id2-expressing progenitor to all interleukin 7 receptor-expressing, “helper-like” ILC lineages, the CHILP. Interestingly, the CHILP differentiated into ILC2 and ILC3 lineages, but not into conventional natural killer (cNK) cells that have been considered an ILC1 subset. Instead, the CHILP gave rise…
Oral trichomonosis: Description and severity of lesions in birds in Spain.
2020
Este artículo se encuentra disponible en la página web de la revista en la siguiente URL: https://www.sciencedirect.com/science/article/abs/pii/S1383576920301264 This is the pre-peer reviewed version of the following article: Martínez-Herrero, M.C., Sansano-Maestre, J., Ortega, J., González, F., López-Márquez, I., Gómez-Muñoz, M.T. et al. (2020). Oral trichomonosis: description and severity of lesions in birds in Spain. Veterinary Parasitology, vol. 283, art. 109196, which has been published in final form at https://doi.org/10.1016/j.vetpar.2020.109196. Este es el pre-print del siguiente artículo: Martínez-Herrero, M.C., Sansano-Maestre, J., Ortega, J., González, F., López-Márquez, I., Góme…
Conflict between parasites with different transmission strategies infecting an amphipod host
2005
Competition between parasites within a host can influence the evolution of parasite virulence and host resistance, but few studies examine the effects of unrelated parasites with conflicting transmission strategies infecting the same host. Vertically transmitted (VT) parasites, transmitted from mother to offspring, are in conflict with virulent, horizontally transmitted (HT) parasites, because healthy hosts are necessary to maximize VT parasite fitness. Resolution of the conflict between these parasites should lead to the evolution of one of two strategies: avoidance, or sabotage of HT parasite virulence by the VT parasite. We investigated two co-infecting parasites in the amphipod host, G…
Interleukin-15 in mycobacterial infection of antigen-presenting cells.
1999
Interleukin-15 (IL-15) shares many biological functions with IL-2 but also exhibits unique effects. Some of these represent the potent chemoattractant activity and expansion of distinct T-cell subsets, particularly memory T cells. IL-15 may therefore modulate the quality and quantity of cellular immune responses directed against intracellular pathogens. Immunohistochemical examination of skin lesions obtained from patients with the lepromatous or the tuberculoid form of Hansen's disease revealed intralesional IL-15 protein in both forms of the disease. In addition to Mycobacterium leprae, a number of different mycobacterial species are capable of effectively inducing IL-15 secretion in infe…
Blattabacteria, the endosymbionts of cockroaches, have small genome sizes and high genome copy numbers.
2008
Summary Blattabacteria are intracellular endosymbionts of cockroaches and primitive termites that belong to the class Flavobacteria and live only in specialized cells in the abdominal fat body of their hosts. In the present study we determined genome sizes as well as genome copy numbers for the endosymbionts of three cockroach species, Blattella germanica, Periplaneta americana and Blatta orientalis. The sole presence of blattabacteria in the fat body was demonstrated by rRNA-targeting techniques. The genome sizes of the three blattabacteria were determined by pulsed field gel electrophoresis. The resulting total genome sizes for the three symbionts were all approximately 650 15 kb. Compari…
Guinea Worm Infection in Dogs: A Case of Reverse Zoonosis that Impedes Dracunculus medinensis Eradication
2020
Dracunculus medinensis or Guinea worm was largely considered an exclusive human parasite. The adult female D. medinensis (up to 100 cm long and 1.5–2.0 mm thick) inhabits and moves in the connective tissue, including the skin. Large females protrude from the skin causing unusual and unambiguous signs. Hosts become infected by drinking water containing the crustacean intermediate hosts (cyclopoid copepods known as water fleas) infected with Guinea worm L3 larvae. After years of a successful eradication campaign (focused mainly on preventing humans from drinking unfiltered or untreated water), Guinea worm transmission has been eliminated from most, but not all, countries. An unforeseeable hig…
Effects of Diets Supplemented with Medicinal Mushroom Myceliated Grains on Some Production, Health, and Oxidation Traits of Dairy Ewes
2019
The beneficial properties of mushrooms’ bioactive compounds indicate their potential for use as performance-enhancing natural additives for livestock animals. A study was undertaken to evaluate the effects of diets supplemented with mushroom myceliated grains (MMGs) fed to dairy ewes on intestinal parasite load, milk production, milk fatty acid (FA) composition, and cheese oxidative stability. During an 8-week experimental period, 21 lactating Valle del Belice ewes were divided into 3 groups named MMG20, MMG10, and MMG0. Ewes in each group were fed hay ad libitum and 1.3 kg/day/head of 1 of 3 concentrates with MMGs at 20% (MMG20), 10% (MMG10), or 0% (MMG0). The ewes fed MMG20 had comparable…
Endoplasmic Reticulum Chaperones in Viral Infection: Therapeutic Perspectives
2021
SUMMARY Viruses are intracellular parasites that subvert the functions of their host cells to accomplish their infection cycle. The endoplasmic reticulum (ER)-residing chaperone proteins are central for the achievement of different steps of the viral cycle, from entry and replication to assembly and exit. The most abundant ER chaperones are GRP78 (78-kDa glucose-regulated protein), GRP94 (94-kDa glucose-regulated protein), the carbohydrate or lectin-like chaperones calnexin (CNX) and calreticulin (CRT), the protein disulfide isomerases (PDIs), and the DNAJ chaperones. This review will focus on the pleiotropic roles of ER chaperones during viral infection. We will cover their essential role …
Infection dynamics of two renal myxozoans in hatchery reared fry and juvenile Atlantic cod Gadus morhua L.
2010
SUMMARYIn order to study the infection dynamics of 2 renal myxozoans, Zschokkella hildae Auerbach, 1910 and Gadimyxa atlanticaKøie, Karlsbakk and Nylund, 2007 in cultured Atlantic cod, Gadus morhua L. aged 3–19 months, a specific single-round PCR assay and a double-label in situ hybridization protocol were developed. The results demonstrated that the 2 myxozoans show spatial separation of their development with regard to spore formation inside the renal tubules versus the collecting ducts and ureters, as well as temporal separation with Z. hildae proliferating and developing spores only once the G. atlantica infection decreases, despite the presence of both myxozoans in the smallest fry stu…