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6,217 result(s) for "Toxoplasma Gondii"
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Prevalence of Toxoplasma gondii-like oocyst shedding in feral and owned cats in Damascus, Syria
Abstract Background The incidence of toxoplasmosis in humans in Syria indicates an increase in the number of infections with this disease. Cats are the only definitive host of Toxoplasma gondii and excrete environmentally resistant oocysts in their feces. Objectives Estimate the prevalence of T. gondii-like oocyst shedding in the cat population in Damascus, Syria. Animals One-hundred domestic cats. Methods One-hundred fecal samples from cats (68 feral cats and 32 owned cats) were collected in Damascus between October and December 2017 and examined for T. gondii-like oocysts by direct microscopic examination using Sheather's sugar flotation procedure. Results Examination of the samples showed that 36% (36/100) of the cats were shedding T. gondii-like oocysts. Sporulated or unsporulated oocysts morphologically consistent with T. gondii were detected in 38.2% (26/68) of the samples collected from feral cats and in 31.3% (10/32) of the samples collected from client-owned cats. Conclusion The clinical importance of Toxoplasmosis in humans lies in the transmission of Toxoplasma to the fetus especially in the first trimester, resulting in severe clinical symptoms in the infant and leading to spontaneous abortion, stillbirth or other serious health problems and severe sequelae (e.g., mental retardation, blindness, hearing, and neurological disorders). Our results showed higher prevalence in Syria than in Lebanon. High amounts of T. gondii-like oocyst shedding were detected in both feral and client-owned cats in Damascus, emphasizing the importance of further research to understand T. gondii infection in people and animals in this region.
Anti- Toxoplasma activity of various molecular weights and concentrations of chitosan nanoparticles on tachyzoites of RH strain
Natural polysaccharides such as chitosan (CS) are widely used as antimicrobial agents. In recent years, and considering that CS has a strong antimicrobial potential, interest has been focused on antimicrobial activity of chitosan nanoparticles (CS NPs). The main factors affecting the antibacterial activity of chitosan include molecular weight (MW) and concentration. In this regard, the aim of this study was to produce various MWs and concentrations of CS NPs, through the ionic gelation method, and investigate their potential anti-parasitic activity against tachyzoites of RH strain. The MWs and degree of deacetylation of the CS were characterized using viscometric and acid-base titration methods, respectively. The efficacy of various MWs and concentrations of NPs was assessed by performing in vitro experiments for tachyzoites of RH strain, such as MTT assay, scanning electron microscopy, bioassay in mice and PCR. In vivo experiment was carried out in BALB/c mice which were inoculated with tachyzoites of RH strain and treated with various MWs of CS NPs. The results of in vitro and in vivo experiments revealed that anti- activity strengthened as the CS NPs concentration increased and the MW decreased. In vitro experiment showed 100% mortality of tachyzoites at 500 and 1,000 ppm concentrations of low molecular weight (LMW) CS NPs after 180 min and at 2,000 ppm after 120 min. Furthermore, a 100% mortality of tachyzoites was observed at 1,000 and 2,000 ppm concentrations of medium molecular weight (MMW) CS NPs and at 2,000 ppm concentration of high molecular weight (HMW) CS NPs after 180 min. Growth inhibition rates of tachyzoites in peritoneal exudates of mice receiving low, medium and high MWs of CS NPs were found to be 86%, 84% and 79% respectively, compared to those of mice in sulfadiazine treatment group (positive control). Various MWs of CS NPs exhibited great anti- efficiency against tachyzoites of RH strain, with the greatest efficacy shown by LMW CS NPs in both experiments. It seems that CS NPs can be used as an alternative natural medicine in the treatment of toxoplasmosis.
Development and validation of a gra1–bag1 RT-qPCR assay as an alternative to the mouse bioassay for assessing Toxoplasma gondii viability
Toxoplasmosis is a major foodborne zoonosis causing high global disease burden and economic losses in sheep and goat industries. The gold standard for detecting viable Toxoplasma gondii is the mouse bioassay, which involves inoculating tissues from infected animals into laboratory mice. Here, we describe a faster, cost-effective, and ethical alternative method to assess T. gondii presence and viability. The procedure is based on reverse transcription quantitative PCR (RT-qPCR) targeting messenger RNA transcripts of genes highly expressed during infection, including the bradyzoite-specific gene bag1 , indicative of chronic infection and gra1 , which detects both acute and chronic infections due to high transcription in tachyzoites and bradyzoites. This RT-qPCR assay was evaluated alongside the mouse bioassay and two molecular methods, 529 bp-specific qPCR and nested ITS-1 PCR, using tissues from experimentally infected piglets and sheep. Cohen’s kappa coefficient showed moderate agreement between gra1–bag1 RT-qPCR and the mouse bioassay (κ = 0.557), comparable to 529-qPCR (κ = 0.556). The assay detected gra1 and bag1 transcripts in all bioassay-positive samples, demonstrating high predictive value for viable parasites. The gra1–bag1 RT-qPCR provides a reliable prescreening tool for predicting parasite viability in tissues, supporting ethical research by reducing reliance on the mouse bioassay.
Trends of Toxoplasma gondii and common transfusable venereal infections among blood donors in Menoufia Province, Egypt
Blood transfusion has a hazard of transmission of many pathogens, including Toxoplasma gondii ( T. gondii ) and other venereal infections. It is crucial to conduct epidemiological surveillance to detect the prevalence of these pathogens. The study aimed to assess the seroprevalence of T. gondii and common transfusable venereal infections among healthy blood donors in Menoufia Province, Egypt, and identify associated risk factors. Four hundred twenty individuals were recruited between January and April 2023 for cross-sectional descriptive research from the blood banks of Menoufia University medical hospitals. Collected blood samples were screened for anti- T. gondii IgM and IgG, HBsAg, anti-HCV antibodies, HIV p24 antigen and anti-HIV antibodies, and anti- Treponema pallidum antibodies. 46 (11.0%) and 22 donors (5.2%) individuals tested positive for anti- T. gondii IgG with a 95% CI (8.3–14.6) and IgM with a 95% CI (3.5–8.1), respectively, while one patient (0.2%) was positive for both antibodies. Regarding venereal infections, 12 (2.9%) were positive for HBV, 6 (1.4%) were positive for HCV, 7 (1.7%) were positive for HIV, and none of the tested population showed positivity for syphilis. Female gender, consumption of raw meat, agricultural environment, poor awareness about T. gondii , and blood group type (especially AB and O groups) were identified as independent risk factors for T. gondii infection. The study highlights the importance of testing blood donors for T. gondii and common transfusable venereal illnesses. Starting health education programs and preventative measures, such as suitable meat handling and cleanliness practices, is critical for minimizing the occurrence of these illnesses. Larger-scale additional study is advised to confirm these results and provide guidance for public health initiatives.
Curcumin nanoemulsion as a novel chemical for the treatment of acute and chronic toxoplasmosis in mice
The aim of this study was to prepare curcumin nanoemulsion (CR-NE) to solve the problems associated with poor water solubility and low bioavailability of CR and to test its efficiency in the treatment of acute and chronic toxoplasmosis in mouse models. CR-NE 1% was prepared using spontaneous emulsification by soybean as oil phase; a mixture of Tween 80 and Tween 85 as surfactant; ethanol as cosurfactant and distilled water. Particle size and zeta potential of NE were assessed using Nano-ZS90 dynamic light scattering. Stability testing of NE was assessed after storage for 2 months at room temperature. In vivo experiments were carried out using 50 BALB/c mice inoculated with virulent RH strain (type I) and 50 BALB/c mice inoculated with avirulent Tehran strain (type II) of and treated with CR-NE (1% w/v), CR suspension (CR-S, 1% w/v), and NE without CR (NE-no CR). The mean particle size and zeta potential of CR-NE included 215.66±16.8 nm and -29.46±2.65 mV, respectively, and were stable in particle size after a three freeze-thaw cycle. In acute phase experiment, the survival time of mice infected with RH strain of and treated with CR-NE extended from 8 to 10 days postinoculation. The differences were statistically significant between the survival time of mice in CR-NE-treated group compared with negative control group ( <0.001). Furthermore, CR-NE significantly decreased the mean counts of peritoneum tachyzoites from 5,962.5±666 in negative control group to 627.5±73 in CR-NE-treated mice ( <0.001). Growth inhibition rates of tachyzoites in peritoneum of mice receiving CR-NE, CR-S, and NE-no CR included 90%, 21%, and 11%, respectively, compared with negative control group. In chronic phase experiment, the average number and size of tissue cysts significantly decreased to 17.2±15.6 and 31.5±6.26 µm, respectively, in mice inoculated with bradyzoites of Tehran strain and treated with CR-NE compared with that in negative control group ( <0.001). Decrease of cyst numbers was verified by downregulation of BAG1 in treatment groups compared with negative control group with a minimum relative expression in CR-NE (1.12±0.28), CR-S (11.76±0.87), and NE-no CR (14.67±0.77), respectively, ( <0.001). Results from the current study showed the potential of CR-S and CR-NE in treatment of acute and chronic toxoplasmosis in mouse models for the first time. However, CR-NE was more efficient than CR-S, and it seems that CR-NE has a potential formula for the treatment of acute and chronic toxoplasmosis, especially in those with latent bradyzoites in brain.
Five years of the biggest outbreak of human toxoplasmosis in Santa Maria, Brazil: a review
Toxoplasmosis is a parasitic disease caused by infection with the protozoan Toxoplasma gondii . In 2018, the first cases of people with clinical signs of acute febrile syndrome were reported, and in the same year, the largest outbreak of human toxoplasmosis ever described in the literature was reported. In this sense, the present work sought to describe the evolution of the outbreak cases in the municipality of Santa Maria, Rio Grande do Sul State, Brazil, as well as the studies conducted and published during and after the outbreak in the municipality (the period between 2018 and 2023). In addition, the discussion of public policies and their modifications after the notification of this outbreak. As a result of this research, verifying the evolution of notified and confirmed cases, the possibility of detection and genotypic characterization of T. gondii and the possibility of co-infections and evaluation of the humoral response is possible. With regard to public policies, the importance of detecting the agent through the heel prick test and increasing the monitoring of water quality to prevent outbreaks.
The acyl-CoA synthetase TgACS1 allows neutral lipid metabolism and extracellular motility in Toxoplasma gondii through relocation via its peroxisomal targeting sequence (PTS) under low nutrient conditions
Apicomplexa parasites cause major diseases such as toxoplasmosis and malaria that have major health and economic burdens. These unicellular pathogens are obligate intracellular parasites that heavily depend on lipid metabolism for the survival within their hosts. Their lipid synthesis relies on an essential combination of fatty acids (FAs) obtained from both de novo synthesis and scavenging from the host. The constant flux of scavenged FA needs to be channeled toward parasite lipid storage, and these FA storages are timely mobilized during parasite division. In eukaryotes, the utilization of FA relies on their obligate metabolic activation mediated by acyl-co-enzyme A (CoA) synthases (ACSs), which catalyze the thioesterification of FA to a CoA. Besides the essential functions of FA for parasite survival, the presence and roles of ACS are yet to be determined in Apicomplexa. Here, we identified TgACS1 as a Toxoplasma gondii cytosolic ACS that is involved in FA mobilization in the parasite specifically during low host nutrient conditions, especially in extracellular stages where it adopts a different localization. Heterologous complementation of yeast ACS mutants confirmed TgACS1 as being an Acyl-CoA synthetase of the bubble gum family that is most likely involved in β-oxidation processes. We further demonstrate that TgACS1 is critical for gliding motility of extracellular parasite facing low nutrient conditions, by relocating to peroxisomal-like area.IMPORTANCEToxoplasma gondii, causing human toxoplasmosis, is an Apicomplexa parasite and model within this phylum that hosts major infectious agents, such as Plasmodium spp., responsible for malaria. The diseases caused by apicomplexans are responsible for major social and economic burdens affecting hundreds of millions of people, like toxoplasmosis chronically present in about one-third of the world’s population. Lack of efficient vaccines, rapid emergence of resistance to existing treatments, and toxic side effects of current treatments all argue for the urgent need to develop new therapeutic tools to combat these diseases. Understanding the key metabolic pathways sustaining host-intracellular parasite interactions is pivotal to develop new efficient ways to kill these parasites. Current consensus supports parasite lipid synthesis and trafficking as pertinent target for novel treatments. Many processes of this essential lipid metabolism in the parasite are not fully understood. The capacity for the parasites to sense and metabolically adapt to the host physiological conditions has only recently been unraveled. Our results clearly indicate the role of acyl-co-enzyme A (CoA) synthetases for the essential metabolic activation of fatty acid (FA) used to maintain parasite propagation and survival. The significance of our research is (i) the identification of seven of these enzymes that localize at different cellular areas in T. gondii parasites; (ii) using lipidomic approaches, we show that TgACS1 mobilizes FA under low host nutrient content; (iii) yeast complementation showed that acyl-CoA synthase 1 (ACS1) is an ACS that is likely involved in peroxisomal β-oxidation; (iv) the importance of the peroxisomal targeting sequence for correct localization of TgACS1 to a peroxisomal-like compartment in extracellular parasites; and lastly, (v) that TgACS1 has a crucial role in energy production and extracellular parasite motility.
Seroprevalence and Risk Factors for Toxoplasma gondii Infection in People Living with HIV: A Cross-Sectional Study from Maputo Central Hospital, Mozambique
This study aimed to determine the seroprevalence of toxoplasmosis in people living with HIV (PWH) in Maputo, Mozambique, exploring the interactions between HIV/acquired immunodeficiency syndrome (AIDS) and toxoplasmosis, including HIV-related factors such as the World Health Organization (WHO) HIV/AIDS clinical stage, degree of immunosuppression based on CD4 T-cell count, and associated risk factors. Additionally, it aimed to assess the prevalence of neurological and psychiatric disorders (NPD) among study participants and its possible association with toxoplasmosis seropositivity. We conducted a descriptive, cross-sectional study of 200 patients aged >18 years who were admitted to Maputo Central Hospital, Maputo, Mozambique, between March 2020 and October 2021. The participants were recruited by convenience, regardless of the reason for their admission. Sociodemographic and clinical data, such as age, sex, WHO HIV/AIDS stage, and CD4 T-cell count, were collected. NPD disorders were assessed using the International Classification of Diseases criteria. Venous blood (5 mL) was obtained from each participant to determine anti- IgM and IgG antibodies using commercial enzyme-linked immunosorbent assay. Participants were aged 18-72 years, with the majority being female (64%) and unemployed (57%). Overall, 54.5% of patients tested positive for at least one anti- IgG (52%) or IgM (6.5%). Risk factors for infection ( < 0.05) were associated with age group 18-28 years, being male and unemployed. Moreover, 68.5% of the participants had NPD and of those, 65.1% exhibited anti- antibodies. We found a significant association between anxiety and IgM seropositivity for = 0.016. Though three out of four participants with positive anti- IgG had mood disorders, no significant association was found between infection with mood disorders, nor with other NPD assessed (56% depression, 33% motor disorder, 25.5% psychosis, 17% cognitive impairment, 7.5% mental retardation). Toxoplasmosis may contribute to NPD in PWH patients. Further studies are recommended to better understand the complex interactions between , NPD disorders, and HIV.
Inhibition of Toxoplasma gondii by 1,2,4-triazole-based compounds: marked improvement in selectivity relative to the standard therapy pyrimethamine and sulfadiazine
A safer treatment for toxoplasmosis would be achieved by improving the selectivity profile of novel chemotherapeutics compared to the standard therapy pyrimethamine (PYR) and sulfadiazine (SDZ). We previously reported on the identification of the compounds with imidazole-thiosemicarbazide scaffold as potent and selective anti-Toxoplasma gondii (T. gondii) agents. In our current research, we report on the optimisation of this chemical scaffold leading to the discovery cyclic analogue 20 b with s-triazole core structure. This compound displayed prominent CC 30 to IC 50 selectivity index (SI) of 70.72, making it 160-fold more selective than SDZ, 11-fold more selective than PYR, and 4-fold more selective than trimethoprim (TRI). Additionally, this compound possesses prerequisite drug-like anti-Toxoplasma properties to advance into preclinical development; it showed ability to cross the BBB, did not induce genotoxic and haemolytic changes in human cells, and as well as it was characterised by low cellular toxicity.
Genetic Disruption of Toxoplasma gondii peroxiredoxin (TgPrx) 1 and 3 Reveals the Essential Role of TgPrx3 in Protecting Mice from Fatal Consequences of Toxoplasmosis
Toxoplasma gondii is a worldwide protozoan parasite that endangers human health and causes enormous economic losses to the animal production sector. A safe and effective vaccine or treatment is needed to reduce these hazards. In this study, we revealed the cyto-nuclear and mitochondrial localization of TgPrx1 and TgPrx3 proteins, respectively. We knocked out the T. gondii peroxiredoxin (TgPrxKO) 1 and 3 genes using a parental type II Prugniaud strain lacking KU80 and HXGPRT genes (PruΔku80Δhxgprt) via CRISPR-Cas9 technology. The successful KO was confirmed using PCR, IFAT, and Western blotting in two clones of both target genes, named TgPrx1KO and TgPrx3KO. Regarding in vitro assays, no significant variations between any of the knocked-out clones in TgPrx1KO or TgPrx3KO parasite strains, or even PruΔku80Δhxgprt, were obtained in rates of infection, proliferation, or egress. Nevertheless, mice that were infected with tachyzoites of the TgPrx3KO strain showed a marked decrease in survival rate compared with TgPrx1KO- and PruΔku80Δhxgprt-infected mice. This effect was confirmed using different mouse strains (ICR and C57BL/6J mice), sexes (male and female), and immunological backgrounds (ICR and SCID mice). In addition, TgPrx1KO and TgPrx3KO induced high levels of interferon gamma (IFN-γ) in infected mice at 8 days post infection, and increased IL-6 and IL-12p40 production from murine macrophages cultivated in vitro. The results of the present study suggested that TgPrx3 can induce anti-T. gondii immune responses that protect the mice from fatal consequences of toxoplasmosis. The results of our current and previous studies represent TgPrx3 as an excellent candidate for sub-unit vaccines, suggesting it may contribute to the control of toxoplasmosis for susceptible humans and animals.