Experimental studies on circulating antigen of toxoplasma gondii in intermediate hosts: Criteria for detection and structural properties

Typically illustrating the ‘manipulation hypothesis’, Toxoplasma gondii is widely known to trigger sustainable behavioural changes during chronic infection of intermediate hosts to enhance transmission to its feline definitive hosts, ensuring survival and dissemination. During the chronic stage of infection in rodents, a variety of neurological dysfunctions have been unravelled and correlated with the loss of cat fear, among other phenotypic impacts. However, the underlying neurological alteration(s) driving these behavioural modifications is only partially understood, which makes it difficult to draw more than a correlation between T. gondii infection and changes in brain homeostasis. Moreover, it is barely known which among the brain regions governing fear and stress responses are preferentially affected during T. gondii infection. Studies aiming at an in-depth dissection of underlying molecular mechanisms occurring at the host and parasite levels will be discussed in this review. Addressing this reminiscent topic in the light of recent technical progress and new discoveries regarding fear response, olfaction and neuromodulator mechanisms could contribute to a better understanding of this complex host–parasite interaction.

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Theoretical and experimental studies on the electronic, optical, and structural properties of poly-pyrrole-2-carboxylic acid films

Chemical Physics ◽

10.1016/j.chemphys.2013.08.006 ◽

2013 ◽

Vol 425 ◽

pp. 91-95 ◽

Cited By ~ 2

Author(s):

Mauricio Foschini ◽

Hugo Santos Silva ◽

Raigna A. Silva ◽

Alexandre Marletta ◽

Débora Gonçalves

Keyword(s):

Carboxylic Acid ◽

Structural Properties ◽

Experimental Studies

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Experimental Studies of the Effective Sintering Temperature on Electrical and Structural Properties of HgBa2Ca2Cu3O8+δ Compound

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/871/1/012078 ◽

2020 ◽

Vol 871 ◽

pp. 012078

Author(s):

Firas Kadhim Nsaif ◽

Kareem Ali Jasim ◽

Kassim Mahdi Wadi ◽

B. Alshafaay ◽

Ahlam Rashid Khazaal

Keyword(s):

Structural Properties ◽

Sintering Temperature ◽

Experimental Studies

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Molecular identification of Toxoplasma gondii in roadkill wild animals in Yucatan, Mexico

Veterinaria México OA ◽

10.22201/fmvz.24486760e.2019.1.511 ◽

2019 ◽

Vol 6 (1) ◽

Author(s):

Marco Antonio Torres-Castro ◽

Rodrigo Adán Medina-Pinto ◽

Henry René Noh-Pech ◽

Fernando I. Puerto ◽

Roger Iván Rodríguez-Vivas

Keyword(s):

Toxoplasma Gondii ◽

Animal Health ◽

Negative Control ◽

Molecular Evidence ◽

Wild Animals ◽

Intermediate Hosts ◽

Nested Polymerase Chain Reaction ◽

Muscle Sample ◽

Wild Mammals ◽

Lung Sample

Toxoplasma gondii is an obligate intracellular protozoan parasite, recognized as the etiologic agent of toxoplasmosis, a zoonotic endemic disease in several countries, including Mexico. In the Yucatan State of Mexico, Toxoplasma infection has a high impact in both human and domestic animal health. Wild animals can also host zoonotic pathogens such as Toxoplasma gondii. The presence of Toxoplasma gondii DNA in roadkill wild animals in Yucatan was detected using a nested Polymerase Chain Reaction. Toxoplasma gondii DNA was identified in several organs retrieved from a Yucatan squirrel (Sciurus yucatanensis), a coatimundi (Nasua narica), and a greater grison (Galictis vittata). The amplified fragments of Toxoplasma gondii DNA were purified, sequenced, and certified by BLAST analysis. Our results confirm that Toxoplasma gondii can infect wild mammals from Yucatan, which could act as intermediate hosts and contribute to the transmission of the disease to humans and domestic animals, as well as other wild animal species. We present the first molecular evidence of Toxoplasma gondii in a squirrel and a coatimundi from Yucatan, and quite possibly in a greater grison at a global level.Figure 1. Agarose gel presenting PCR amplicons (560 bp) positive to Toxoplasma gondii. 1) C+: positive control; A: Yucatan squirrel liver sample; B: great grison femoral muscle sample; C: coatimundi kidney sample; C-: negative control. 2) A: Yucatan squirrel brain sample; B: great grison lung sample; C-: negative control.

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Arctigenin ameliorates depression-like behaviors in Toxoplasma gondii-infected intermediate hosts via the TLR4/NF-κB and TNFR1/NF-κB signaling pathways

International Immunopharmacology ◽

10.1016/j.intimp.2020.106302 ◽

2020 ◽

Vol 82 ◽

pp. 106302 ◽

Cited By ~ 3

Author(s):

Jia-Hui Cheng ◽

Xiang Xu ◽

Ying-Biao Li ◽

Xu-Dong Zhao ◽

Fumie Aosai ◽

...

Keyword(s):

Toxoplasma Gondii ◽

Signaling Pathways ◽

Intermediate Hosts

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Tissue cyst tropism in Toxoplasma gondii: a comparison of tissue cyst formation in organs of cats, and rodents fed oocysts

Parasitology ◽

10.1017/s0031182097008949 ◽

1997 ◽

Vol 115 (1) ◽

pp. 15-20 ◽

Cited By ~ 52

Author(s):

J. P. DUBEY

Keyword(s):

Toxoplasma Gondii ◽

Cyst Formation ◽

Tissue Cyst ◽

Intermediate Hosts ◽

Mesenteric Lymph Nodes ◽

Marked Contrast ◽

Mesenteric Lymph ◽

Time Period ◽

Rats And Mice ◽

The Brain

The persistence of Toxoplasma gondii tissue cysts in organs of cats (definitive host) and rodents (intermediate hosts) was studied. Nine cats, 12 rats, and 12 mice were fed T. gondii oocysts and their organs were digested in pepsin and then bioassayed for bradyzoites in mice. Of 9 cats killed 37 or 51 days after feeding 102 (2 cats), 103 (3 cats) or 104 (4 cats) oocysts of the VEG strain, tissue cysts were found in each cat; in the tongue of 9, in the heart of 5, in the brain of 4, and in the eyes of 1 cat. The dose had no effect on the distribution of tissue cysts in cats. Twelve rats were each fed 105 oocysts of the VEG strain of T. gondii and killed 21, 29, 64 or 237 days later. At each time-period, 11 tissues of 3 rats were pooled and bioassayed in mice. Tissue cysts were found in the brain, skeletal muscle, heart and kidneys of rats at each killing time; in the lungs, intestines, and mesenteric lymph nodes in 3 of 4 instances; in the tongue, liver, and eyes in 2 instances and in the spleen in 1 instance. Also, using the same procedures and sampling the same 11 tissues as used for rats, tissue cysts were seen in all organs except in the tongue and liver of 3 mice killed on day 82 after feeding the VEG strain. In 9 mice (3 with each strain) fed oocysts of the ME-49, GT-1, or P89 T. gondii strain and killed 62–130 days later, tissue cysts were found consistently only in the brain. Thus, in rats and mice, most tissue cysts were found in the brain and rarely in the tongue. This was in marked contrast to the distribution of tissue cysts in cats.

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Toxoplasma gondii antibodies and related risk factors in mammals at Sorocaba zoo, São Paulo, BrazilToxoplasma gondii antibodies and related risk factors in mammals at Sorocaba zoo, São Paulo, Brazil

Semina Ciências Agrárias ◽

10.5433/1679-0359.2017v38n4supl1p2845 ◽

2017 ◽

Vol 38 (4Supl1) ◽

pp. 2845

Author(s):

Renata Bezerra Marujo ◽

Helio Langoni ◽

Leila Sabrina Ullmann ◽

Maysa Pellizzaro ◽

Ramiro Das Neves Dias Neto ◽

...

Keyword(s):

Risk Factors ◽

Toxoplasma Gondii ◽

Feeding Habits ◽

Univariate Analysis ◽

Multivariate Logistic Regression Analysis ◽

Sao Paulo ◽

São Paulo ◽

Intermediate Hosts ◽

Serum Samples ◽

Related Risk

Toxoplasmosis is a parasitic zoonosis with worldwide distribution and different wild species either are involved in maintenance of the pathogen in the environment as definitive or intermediate hosts serving as font of feeding or prey to definitive hosts. The present study aimed to investigate Toxoplasma gondii antibodies and the risk factors relating to infection in mammals at Sorocaba Zoo, state of São Paulo, Brazil. Serum samples collected from 153 animals were analyzed using the modified agglutination test (MAT; cutoff ? 25). Seropositivity was found in 62 animals (40.5%; 95% CI: 33.1-48.5%), with different titers. Significant differences were observed in relation to the ages of the animals, origin, presence of free-ranging animals in the enclosure and feeding habits, through univariate analysis (p ? 0.05). Multivariate logistic regression analysis showed that only age (p = 0.03) had significance for the study. Adult animals were 3.5 more likely to become infected than were young ones. In relation to feeding habits, herbivores (80%) and carnivores (46.5%) were the animals most affected. These results highlight the presence of T. gondii in animals at Brazilian zoos, and suggest that continuous transmission is occurring at zoos.

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An updated meta-analysis of the association between Toxoplasma gondii infection and risk of epilepsy

Transactions of the Royal Society of Tropical Medicine and Hygiene ◽

10.1093/trstmh/trz025 ◽

2019 ◽

Vol 113 (8) ◽

pp. 453-462 ◽

Cited By ~ 4

Author(s):

Maryam Sadeghi ◽

Seyed Mohammad Riahi ◽

Mona Mohammadi ◽

Vafa Saber ◽

Somayeh Aghamolaie ◽

...

Keyword(s):

Toxoplasma Gondii ◽

Meta Analysis ◽

Experimental Studies ◽

Positive Association ◽

Final Analysis ◽

Toxoplasma Infection ◽

Significant Positive Association ◽

Worldwide Distribution ◽

Subgroup Analyses ◽

Toxoplasma Gondii Infection

Abstract Toxoplasma gondii is a neurotropic pathogen with worldwide distribution. To evaluate the association between Toxoplasma infection and the risk of epilepsy by meta-analysis, observational peer-reviewed studies were retrieved from PubMed, Embase, Web of Science, Scopus and Google Scholar (up to 10 October 2018) and by reference review. Pooled risk estimates were calculated using a random effects model. Heterogeneity was assessed using Cochrane’s Q-test and I2. In total, 16 eligible studies involving 19 data sets were included for the final analysis. A total 7897 participants (3771 epileptic patients, 4026 healthy controls) were included. The pooled odds ratio (OR) for Toxoplasma infection was increased to 1.72 (95% confidence interval [CI] 1.37 to 2.16) among patients with epilepsy. There was moderate heterogeneity among the studies (χ2=39.8, I2=62.3%, p=0.001). The ORs from subgroup analyses showed that both cryptogenic epilepsy (OR 2.65 [95% CI 1.91 to 3.68]) and active convulsive epilepsy (OR 1.37 [95% CI 1.09 to 1.72]) were significantly associated with Toxoplasma infection. Another subgroup analyses according to age showed a significant positive association in children (OR 1.33), adults (OR 1.57) and in all ages (OR 1.89). Our findings support the association between Toxoplasma infection and epilepsy. More prospective studies with larger sample sizes and more experimental studies are recommended to elucidate a causative relationship.

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