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Toxoplasma gondii primarily invades the central nervous system, causing latent infections. Cysts persist in the host for life and there is currently no effective treatment. T. gondii infects human hosts through contaminated meat, invading the intestinal tissue and leading to changes in the number and composition of the gut microbiota. Since probiotic ingestion modulates intestinal microbiota changes, we hypothesized that intestinal microbiota dysbiosis caused by T. gondii infection would be restored following probiotic supplementation. To this end, we orally infected C57BL/6 mice with 10 T. gondii cysts and administered supplemental probiotics daily. We analyzed the levels of T. gondii B1 gene DNA, indicative of T. gondii infection, in brain tissue. We investigated alterations in the gut microbiota composition and functional pathways between the probiotic and non-probiotic treatment groups via next-generation sequencing analysis of each fecal sample. The infection level in the probiotic-treated group was significantly reduced after 4 weeks (P<0.05). Probiotic supplementation notably changed the gut microbiota after 2 weeks of infection, increasing the relative abundance of Intestinimonas massiliensis and Lawsonibacter asaccharolyticus. Probiotic supplements appear to modulate the gut microbiota, activating functional pathways involved in intestinal short-chain fatty acid production and strengthening the intestinal barrier, thereby impeding T. gondii infection and subsequent proliferation. Our findings provide valuable insights into T. gondii infection control and future study directions. [ABSTRACT FROM AUTHOR]

Sepsis, a leading cause of death worldwide, is a harmful inflammatory condition that is primarily caused by an endotoxin released by Gram-negative bacteria. Effective targeted therapeutic strategies for sepsis are lacking. In this study, using an in vitro and in vivo mouse model, we demonstrated that CM1, a derivative of the natural polyphenol chrysin, exerts an anti-inflammatory effect by inducing the expression of the ubiquitin-editing protein TNFAIP3 and the NAD-dependent deacetylase sirtuin 1 (SIRT1). Interestingly, CM1 attenuated the Toll-like receptor 4 (TLR4)-induced production of inflammatory cytokines by inhibiting the extracellular-signal-regulated kinase (ERK)/MAPK and nuclear factor kappa B (NF-κB) signalling pathways. In addition, CM1 induced the expression of TNFAIP3 and SIRT1 on TLR4-stimulated primary macrophages; however, the anti-inflammatory effect of CM1 was abolished by the siRNA-mediated silencing of TNFAPI3 or by the genetic or pharmacologic inhibition of SIRT1. Importantly, intravenous administration of CM1 resulted in decreased susceptibility to endotoxin-induced sepsis, thereby attenuating the production of pro-inflammatory cytokines and neutrophil infiltration into the lung compared to control mice. Collectively, these findings demonstrate that CM1 has therapeutic potential for diverse inflammatory diseases, including sepsis. [ABSTRACT FROM AUTHOR]

Aim: To investigate the anticancer mechanisms of silver nanoparticles (AgNPs) in colorectal cancer. Methods: Anticancer effects of AgNPs were determined in colorectal cancer HCT116 cells and xenograft mice using cellular and molecular methods. Results: AgNPs induced mitochondrial reactive oxygen species production, mitochondrial dysfunction and endoplasmic reticulum (ER) stress responses through NOX4 and led to HCT116 cell apoptosis. Pretreatment with DPI or 4-PBA significantly inhibited mitochondrial reactive oxygen species production, apoptosis, ER stress response, NOX4 expression and mitochondrial dysfunction in AgNP-treated HCT116 cells. AgNPs also significantly suppressed HCT116 cell-based xenograft tumor growth in nude mice by inducing apoptosis and ER stress responses. Conclusion: AgNPs exert anticancer effects against colorectal cancer via ROS- and ER stress-related mitochondrial apoptosis pathways. [ABSTRACT FROM AUTHOR]

This paper proposes a novel indexing method for complex similarity queries in high-dimensional image and video systems. In order to provide the indexing method with the flexibility in dealing with multiple features and multiple query objects, we treat every dimension independently. The efficiency of our method is realized by a specialized bitmap indexing that represents all objects in a database as a set of bitmaps. The percentage of data accessed in our indexing method is inversely proportional to the overall dimensionality, and thus the performance deterioration with the increasing dimensionality does not occur. To demonstrate the efficacy of our method we conducted extensive experiments and compared the performance with the VA-file-based index and the linear scan by using real image and video datasets, and obtained a remarkable speed-up over them. [ABSTRACT FROM AUTHOR]

Omega-3 polyunsaturated fatty acids (ω3-PUFAs) have potential protective activity in a variety of infectious diseases, but their actions and underlying mechanisms in Toxoplasma gondii infection remain poorly understood. Here, we report that docosahexaenoic acid (DHA) robustly induced autophagy in murine bone marrow-derived macrophages (BMDMs). Treatment of T. gondii-infected macrophages with DHA resulted in colocalization of Toxoplasma parasitophorous vacuoles with autophagosomes and reduced intracellular survival of T. gondii. The autophagic and anti-Toxoplasma effects induced by DHA were mediated by AMP-activated protein kinase (AMPK) signaling. Importantly, BMDMs isolated from Fat-1 transgenic mice, a well-known animal model capable of synthesizing ω3-PUFAs from ω6-PUFAs, showed increased activation of autophagy and AMPK, leading to reduced intracellular survival of T. gondii when compared with wild-type BMDMs. Moreover, Fat-1 transgenic mice exhibited lower cyst burden in the brain following infection with the avirulent strain ME49 than wild-type mice. Collectively, our results revealed mechanisms by which endogenous ω3-PUFAs and DHA control T. gondii infection and suggest that ω3-PUFAs might serve as therapeutic candidate to prevent toxoplasmosis and infection with other intracellular protozoan parasites. [ABSTRACT FROM AUTHOR]