المؤلفون: Juliana Magalhães Chaves Barbosa, Yasmin Pedra-Rezende, Luíza Dantas Pereira, Tatiana Galvão de Melo, Helene Santos Barbosa, Joseli Lannes-Vieira, Solange Lisboa de Castro, Anissa Daliry, Kelly Salomão

المصدر: Frontiers in Cellular and Infection Microbiology, Vol 12 (2022)

مصطلحات موضوعية: Trypanosoma cruzi, Chagas disease, amiodarone, benznidazole, combined treatment, Microbiology, QR1-502

الوصف: Chagas disease (CD), a neglected tropical disease caused by the protozoan parasite Trypanosoma cruzi, is an important public health problem mainly in Latin America, leading to approximately 12,000 annual deaths. Current etiological treatment for CD is limited to two nitro compounds, benznidazole (Bz) and nifurtimox (Nif), both presenting relevant limitations. Different approaches have been employed to establish more effective and safer schemes to treat T. cruzi infection, mostly based on drug repurposing and combination therapies. Amiodarone (AMD), an antiarrhythmic medicament of choice for patients with the chronic cardiac form of CD, is also recognized as a trypanocidal agent. Therefore, our aim is to investigate the combined treatment Bz + AMD on trypomastigote viability, control of T. cruzi intracellular form proliferation, and recovery of the infection-induced cytoskeleton alterations in cardiac cells. The combination of Bz + AMD did not improve the direct trypanocidal effect of AMD on the infective blood trypomastigote and replicative intracellular forms of the parasite. Otherwise, the treatment of T. cruzi-infected cardiac cells with Bz plus AMD attenuated the infection-triggered cytoskeleton damage of host cells and the cytotoxic effects of AMD. Thus, the combined treatment Bz + AMD may favor parasite control and hamper tissue damage.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/articles/10.3389/fcimb.2022.975931/fullTest; https://doaj.org/toc/2235-2988Test

الوصول الحر: https://doaj.org/article/39b4615c95fa44f8aec504533d789357Test

المؤلفون: Mariana Acquarone, A. Poleto, A. F. Perozzo, P. F. R. Gonçalves, R. Panizzutti, J. R. L. Menezes, G. A. Neves, Helene Santos Barbosa

المصدر: Scientific Reports, Vol 11, Iss 1, Pp 1-9 (2021)

مصطلحات موضوعية: Medicine, Science

الوصف: Abstract Toxoplasma gondii is an opportunistic protozoan pathogen with a wide geographic distribution. The chronic phase of toxoplasmosis is often asymptomatic in humans and is characterized by tissue cysts throughout the central nervous system and muscle cells. T. gondii and other pathogens with tropism for the central nervous system are considered risk factors in the etiology of several neuropsychiatric disorders, such as schizophrenia and bipolar disorder, besides neurological diseases. Currently, it is known that cerebral toxoplasmosis increases dopamine levels in the brain and it is related to behavioral changes in animals and humans. Here we evaluate whether chronic T. gondii infection, using the cystogenic ME-49 strain, could induce behavioral alterations associated with neuropsychiatric disorders and glutamatergic neurotransmission dysfunction. We observed that the startle amplitude is reduced in the infected animals as well as glutamate and D-serine levels in prefrontal cortical and hippocampal tissue homogenates. Moreover, we did not detect alterations in social preference and spontaneous alternation despite severe motor impairment. Thus, we conclude that behavioral and cognitive aspects are maintained even though severe neural damage is observed by chronic infection of C57Bl/6 mice with the ME-49 strain.

وصف الملف: electronic resource

العلاقة: https://doaj.org/toc/2045-2322Test

الوصول الحر: https://doaj.org/article/bd2cc3c35f5f4550b7f9169b029849f7Test

المؤلفون: Paloma de Carvalho Vieira, Mariana Caldas Waghabi, Daniela Gois Beghini, Danilo Predes, Jose Garcia Abreu, Vincent Mouly, Gillian Butler-Browne, Helene Santos Barbosa, Daniel Adesse

المصدر: Frontiers in Cellular and Infection Microbiology, Vol 9 (2019)

مصطلحات موضوعية: Toxoplasma gondii, myogenesis, C2C12 cells, myotube, myogenic regulatory factor, congenital toxoplasmosis, Microbiology, QR1-502

الوصف: Toxoplasma gondii is the causative agent of toxoplasmosis, a parasitic disease with a wide global prevalence. The parasite forms cysts in skeletal muscle cells and neurons, although no evident association with inflammatory infiltrates has been typically found. We studied the impact of T. gondii infection on the myogenic program of mouse skeletal muscle cells (SkMC). The C2C12 murine myoblast cell line was infected with T. gondii tachyzoites (ME49 strain) for 24 h followed by myogenic differentiation induction. T. gondii infection caused a general decrease in myotube differentiation, fusion and maturation, along with decreased expression of myosin heavy chain. The expression of Myogenic Regulatory Factors Myf5, MyoD, Mrf4 and myogenin was modulated by the infection. Infected cultures presented increased proliferation rates, as assessed by Ki67 immunostaining, whereas neither host cell lysis nor apoptosis were significantly augmented in infected dishes. Cytokine Bead Array indicated that IL-6 and MCP-1 were highly increased in the medium from infected cultures, whereas TGF-β1 was consistently decreased. Inhibition of the IL-6 receptor or supplementation with recombinant TGF-β failed to reverse the deleterious effects caused by the infection. However, conditioned medium from infected cultures inhibited myogenesis in C2C12 cells. Activation of the Wnt/β-catenin pathway was impaired in T. gondii-infected cultures. Our data indicate that T. gondii leads SkMCs to a pro-inflammatory phenotype, leaving cells unresponsive to β-catenin activation, and inhibition of the myogenic differentiation program. Such deregulation may suggest muscle atrophy and molecular mechanisms similar to those involved in myositis observed in human patients.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/article/10.3389/fcimb.2019.00395/fullTest; https://doaj.org/toc/2235-2988Test

الوصول الحر: https://doaj.org/article/bb98879370a74f49ab53a400f6066fdfTest

المؤلفون: Tainá Carneiro de Castro Monte, Brunna Vianna Braga, Maurício Carvalho de Vasconcellos, Arnon Dias Jurberg, Ester Maria Mota, Helene Santos Barbosa, Juberlan Silva Garcia, Arnaldo Maldonado Júnior

المصدر: Revista Brasileira de Parasitologia Veterinária, Iss 0 (2018)

مصطلحات موضوعية: Modelo experimental, herbicida, ensaios in vitro, morfologia, trematódeo, Animal culture, SF1-1100

الوصف: Abstract Helminth parasites have been studied as potential accumulators for different pollutants. Echinostoma paraensei is a foodborne trematode whose vertebrate host, the rodent Nectomys squamipes, is naturally exposed to environmental pesticides. However, little information exists regarding the pesticide’s effects on helminths. This study investigated the morphological effects on the trematode, E. paraensei, after experimental Roundup® herbicide exposure, in concentrations below those recommended for agricultural use. After two hours of exposure, scanning electron microscopy (SEM) showed changes to the tegument, such as furrowing, shrinkage, peeling, spines loss on the peristomic collar, and histopathological evidence of altered cells in the cecum and acinus vitelline glands with vacuoles and structural changes to the muscular layers. Glycidic content was decreased, primarily in the connective tissue. As E. paraensei is an intestinal parasite of the semi-aquatic wild rodent, N. squamipes, it is predisposed to pesticide exposure resulting from agricultural practices. Therefore, we emphasize the need to evaluate its impact on helminth parasites, due to their pivotal role in regulating host populations.

وصف الملف: electronic resource

العلاقة: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-29612018005001104&lng=en&tlng=enTest; https://doaj.org/toc/1984-2961Test

الوصول الحر: https://doaj.org/article/097fac52362b42b283682e85fbde4363Test

المؤلفون: Maria Clara Pamplona-Basilio, Helene Santos Barbosa, Simone Chinicz Cohen

المصدر: Revista Brasileira de Parasitologia Veterinária, Vol 20, Iss 4, Pp 342-346 (2011)

مصطلحات موضوعية: Monogenea, parasitos, peixes, topografia da superfície, parasites, fishes, surface topography, Animal culture, SF1-1100

الوصف: Gotocotyla acanthura (Parona & Perugia, 1896) Meserve, 1938 collected from the gills of Pomatomus saltatrix from the coast of the state of Rio de Janeiro state was analyzed using scanning electron microscopy (SEM). The study demonstrated the presence of a buccal cavity, a genital atrium on the ventral surface and a muscular structure on the dorsal surface at the level of the body constriction. An elongated haptor with 80 to 120 pedunculated clamps symmetrically distributed in two rows, with rib-like thickenings and a curved lappet bearing a pair of hooks at the posterior extremity of the body were also observed. The cirrus could be seen protruding from the genital atrium, armed with pectinate spines along its length and presenting up to eight pointed spines around the genital atrium.Gotocotyla acanthura (Parona & Perugia, 1896) Meserve, 1938, coletado das brânquias de Pomatomus saltatrix do litoral do Estado do Rio de Janeiro, foi estudado por microscopia eletrônica de varredura (MEV). O estudo demonstrou a presença de uma cavidade bucal, átrio genital na superfície ventral e uma estrutura muscular na superficie dorsal ao nível da constricção do corpo. Na extremidade posterior do corpo, foi observado o haptor alongado, apresentando 80 a 120 pinças pedunculadas, distribuídas em duas fileiras simétricas e uma porção terminal curvada provida de um par de ganchos. O cirro foi visualizado projetando-se do átrio genital, armado com espinhos pectinados ao longo do seu comprimento, apresentando até 8 espinhos pontiagudos ao redor do átrio.

وصف الملف: electronic resource

العلاقة: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-29612011000400016Test; https://doaj.org/toc/0103-846XTest; https://doaj.org/toc/1984-2961Test

الوصول الحر: https://doaj.org/article/dcb0e80ba4ee4569bc2f280660ffcc75Test

المؤلفون: Marialice da Fonseca Ferreira-da-Silva, Renata Mendonça Rodrigues, Elisabete Ferreira de Andrade, Laís de Carvalho, Uwe Gross, Carsten G K Lüder, Helene Santos Barbosa

المصدر: Memorias do Instituto Oswaldo Cruz, Vol 104, Iss 2, Pp 196-200 (2009)

مصطلحات موضوعية: Toxoplasma gondii, stage conversion, T. gondii-host cell interaction, skeletal muscle cell, tachyzoite, bradyzoite, Microbiology, QR1-502, Infectious and parasitic diseases, RC109-216

الوصف: Although the predilection for Toxoplasma gondii to form cysts in the nervous system and skeletal and heart muscles has been described for more than fifty years, skeletal muscle cells (SkMCs) have not been explored as a host cell type to study the Toxoplasma-host cell interaction and investigate the intracellular development of the parasite. Morphological aspects of the initial events in the Toxoplasma-SkMC interaction were analysed and suggest that there are different processes of protozoan adhesion and invasion and of the subsequent fate of the parasite inside the parasitophorous vacuole (PV). Using scanning electron microscopy,Toxoplasma tachyzoites from the mouse-virulent RH strain were found to be attached to SkMCs by the anterior or posterior region of the body, with or without expansion of the SkMC membrane. This suggests that different types of parasite internalization occurred. Asynchronous multiplication and differentiation of T. gondii were observed. Importantly, intracellular parasites were seen to display high amounts of amylopectin granules in their cytoplasm, indicating that tachyzoites of the RH strain were able to differentiate spontaneously into bradyzoites in SkMCs. This stage conversion occurred in approximately 3% of the PVs. This is particularly intriguing as tachyzoites of virulent Toxoplasma strains are not thought to be prone to cyst formation. We discuss whether biological differences in host cells are crucial to Toxoplasma stage conversion and suggest that important questions concerning the host cell type and its relevance in Toxoplasma differentiation are still unanswered.

وصف الملف: electronic resource

العلاقة: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0074-02762009000200012Test; https://doaj.org/toc/0074-0276Test; https://doaj.org/toc/1678-8060Test

الوصول الحر: https://doaj.org/article/24247f2894bd4df3806845e30c0f9d80Test

المؤلفون: Erick Vaz Guimarães, Laís de Carvalho, Helene Santos Barbosa

المصدر: Memorias do Instituto Oswaldo Cruz, Vol 104, Iss 2, Pp 170-174 (2009)

مصطلحات موضوعية: Toxoplasma gondi, tissue cysts, bradyzoites, cystogenesis, skeletal muscle cells, Microbiology, QR1-502, Infectious and parasitic diseases, RC109-216

الوصف: Infection by the protozoan parasite Toxoplasma gondii is widely prevalent in humans and animals. To prevent human infection, all meat should be well cooked before consumption, since the parasite is present in skeletal muscle. In this context, the use of skeletal muscle cells (SkMCs) as a cellular model opens up new approaches to investigate T. gondii-host cell interactions. Immunofluorescent detection of proteins that are stage-specific for bradyzoites indicated that complete cystogenesis of T. gondii in in vitro cultures of SkMCs occurs after 96 h of infection. Ultrastructural analysis showed that, after 48 h of interaction, there were alterations on the parasitophorous vacuole membrane, including greater thickness and increased electron density at the inner face of the membrane. The present study demonstrates the potential use of primary cultures of SkMCs to evaluate different molecular aspects of T. gondii invasion and cystogenesis and presents a promising in vitro model for the screening of drug activities toward tissue cysts and bradyzoites.

وصف الملف: electronic resource

العلاقة: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0074-02762009000200007Test; https://doaj.org/toc/0074-0276Test; https://doaj.org/toc/1678-8060Test

الوصول الحر: https://doaj.org/article/37003942fe52437a8e963094263eda88Test

المؤلفون: Susana Balmant Emerique Simões, Helene Santos Barbosa, Cláudia Portes Santos

المصدر: Memorias do Instituto Oswaldo Cruz, Vol 104, Iss 1, Pp 106-111 (2009)

مصطلحات موضوعية: Pygidiopsis macrostomum, Heterophyidae, Digenea, Heleobia australis, Poecilia vivipara, life cycle, Microbiology, QR1-502, Infectious and parasitic diseases, RC109-216

الوصف: The life history of the trematode Pygidiopsis macrostomum Travassos, 1928 is described for the first time. Rediae and cercariae were obtained from naturally infected snails Heleobia australis (d´Orbigny), a new first intermediate host. Metacercariae were found encysted in the mesenteries of three naturally infected guppies, Phalloptychus januarius (Hensel), Jenynsia multidentata (Jenyns) (new host records) and Poecilia vivipara Bloch and Schneider. Experimental infections were successfully completed in the intermediate hosts H. australis and Poe. vivipara reared in the laboratory and hamsters Mesocricetus auratus Waterhouse were utilised as a definitive host.

وصف الملف: electronic resource

العلاقة: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0074-02762009000100016Test; https://doaj.org/toc/0074-0276Test; https://doaj.org/toc/1678-8060Test

الوصول الحر: https://doaj.org/article/2ba00b9ea9c745f6935c049cbe244479Test

المؤلفون: Andréia Pires Dantas, Kelly Salomão, Helene Santos Barbosa, Solange Lisboa De Castro

المصدر: Memorias do Instituto Oswaldo Cruz, Vol 101, Iss 2, Pp 207-211 (2006)

مصطلحات موضوعية: propolis, natural products, Trypanosoma cruzi, Chagas disease, Microbiology, QR1-502, Infectious and parasitic diseases, RC109-216

الوصف: Propolis has shown activity against pathogenic microorganisms that cause diseases in humans and animals. The ethanol (Et-Blg) and acetone (Ket-Blg) extracts from a Bulgarian propolis, with known chemical compositions, presented similar activity against tissue culture-derived amastigotes. The treatment of Trypanosoma cruzi-infected skeletal muscle cells with Et-Blg led to a decrease of infection and of the intracellular proliferation of amastigotes, while damage to the host cell was observed only at concentration 12.5 times higher than those affecting the parasite. Ultrastructural analysis of the effect of both extracts in epimastigotes revealed that the main targets were the mitochondrion and reservosomes. Et-Blg also affected the mitochondrion-kinetoplast complex in trypomastigotes, offering a potential target for chemotherapeutic agents.

وصف الملف: electronic resource

العلاقة: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0074-02762006000200013Test; https://doaj.org/toc/0074-0276Test; https://doaj.org/toc/1678-8060Test

الوصول الحر: https://doaj.org/article/0b7be00003af4972b84784a0a7c3531dTest

المؤلفون: Maria Beatriz Araújo Silva, José Jurberg, Helene Santos Barbosa, Dayse da Silva Rocha, Rodolfo U Carcavallo, Cleber Galvão

المصدر: Memorias do Instituto Oswaldo Cruz, Vol 100, Iss 6, Pp 549-561 (2005)

مصطلحات موضوعية: Triatoma vandae, Triatoma williami, nymphs, Chagas disease, vectors, Microbiology, QR1-502, Infectious and parasitic diseases, RC109-216

الوصف: Eggs and all nymphs of these species were studied employing light microscopy (LM) and scanning electron microscopy (SEM). The major differences observed by LM in the eggs were related to the presence and the distribution of pores on the surface of their chorion. Morphological differences among three nymphal stages (1st, 3rd, and 5th) development of each species were observed. The differential characteristics are chromatic and in the shape of connexival spots. The ultrastructure of the ventral region of the head and the IX, X, and XI abdominal segments (anal tube) of the both species were described demonstrating morphological differences that can be used for diagnosis of the species.

وصف الملف: electronic resource

العلاقة: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0074-02762005000600009&lng=en&tlng=enTest; https://doaj.org/toc/1678-8060Test

الوصول الحر: https://doaj.org/article/5bbc76308ae3449f981ca24518c7a954Test