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The Influenza A virus (IAV) is a zoonotic pathogen that infects humans and various animal species. Infection with IAV can cause fever, anorexia, and dyspnea and is often accompanied by pneumonia characterized by an excessive release of cytokines (i.e., cytokine storm). Nanodrug delivery systems and nanoparticles are a novel approach to address IAV infections. Herein, UiO-66 nanoparticles (NPs) are synthesized using a high-temperature melting reaction. The in vitro and in vivo optimal concentrations of UiO-66 NPs for antiviral activity are 200 μg mL−1 and 60 mg kg−1, respectively. Transcriptome analysis revealed that UiO-66 NPs can activate the RIG-I-like receptor signaling pathway, thereby enhancing the downstream type I interferon antiviral effect. These NPs suppress inflammation-related pathways, including the FOXO, HIF, and AMPK signaling pathways. The inhibitory effect of UiO-66 NPs on the adsorption and entry of IAV into A549 cells is significant. This study presents novel findings that demonstrate the effective inhibition of IAV adsorption and entry into cells via UiO-66 NPs and highlights their ability to activate the cellular RIG-I-like receptor signaling pathway, thereby exerting an anti-IAV effect in vitro or in mice. These results provide valuable insights into the mechanism of action of UiO-66 NPs against IAV and substantial data for advancing innovative antiviral nanomedicine. [ABSTRACT FROM AUTHOR]

Oral infection of mice with several strains of Toxoplasma gondii results in intestinal pathological lesions, which contributes to the invasion of this parasite. However, the exact mechanism is unclear, and only a few strains have been explored. Here, T. gondii TgSheepCHn5 and TgRedpandaCHn1 strains from sheep and red panda were evaluated. The TgSheepCHn5 and TgRedpandaCHn1 strains induced intestinal lesions, loss of Paneth cells, and gut commensal bacteria dysbiosis in Swiss Webster mice. The lesions and loss of Paneth cells were dependent on IFN-γ and gut commensal bacteria during T. gondii infection. Deleting IFN-γ or gut commensal bacteria suppressed the Th1 immune response, alleviated the lesions and parasite loading, and upregulated the number of Paneth cells. Loss of IFN-γ production accelerated mice death, whereas the deletion of gut commensal bacteria enhanced the survival time of the host. The Th1 cell immune responses have positive and negative effects on toxoplasmosis, resistance to T. gondii infection, and acceleration intestine lesions. Adjustment of Th1 cell responses and gut commensal bacteria may be effective treatments for toxoplasmosis. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii typically causes lifelong chronic infection and has been identified in a variety of intermediate and definitive hosts. Felids are capable of serving as both intermediate and definite hosts for T. gondii infection. However, there is no direct evidence to prove that servals are the intermediate host of T. gondii. In this study, T. gondii antibodies were detected in a serval by a modified agglutination test (titer, 1:200). Viable T. gondii was isolated from the striated muscles of the serval. This strain was further propagated in cell culture and designated as TgServalCHn1. Genetic characterization of DNA derived from cell culture was performed by RFLP‐PCR of 10 markers, as well as polymorphic ROP5 and ROP18 genes. Results showed that this strain of T. gondii belonged to the genotype ToxoDB#20. The ROP5 allele 4 and ROP18 allele 3 suggested that this strain was avirulent, which was further supported by infection in mice. Encephalitis, immune organ necrosis and focal mononuclear cell infiltration in multiple organs were the main pathology characteristics observed in BALB/C mice infected with the TgServalCHn1 strain. To our knowledge, the present study is the first to report the isolation of T. gondii from a serval, which gives direct evidence for servals serving as an intermediate host of T. gondii. The genotyping results revealed the presence of genotype ToxoDB#20 in central China, enriching the scope of the distribution of T. gondii genotypes in Asia. [ABSTRACT FROM AUTHOR]

Abstract: The current paper investigated the removal of the azo dye Orange II from water using advanced oxidation processes based on sulfate radicals. The cobalt oxide catalyst immobilized on graphene oxide (GO) can activate peroxymonosulfate (PMS) for the degradation of Orange II in water. The Co3O4/GO catalyst system was characterized via X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, and X-ray spectroscopy. Results showed that Co3O4 was distributed on GO. The Co3O4/GO catalyst system exhibited high activity in Orange II oxidation when the Co3O4/GO catalyst has an optimum Co3O4 loading. In addition, 100% decomposition could be achieved within 6min with 0.2mM Orange II, 0.1gL−1 catalyst, and 2mM PMS. Meanwhile, inductively coupled plasma analysis revealed that the leach of cobalt ions was low. The catalyst also exhibited stable performance after several rounds of regeneration. Several operational parameters, such as catalyst amount, oxidant amount, pH, temperature, and oxidation rate, affected the degradation of Orange II. [Copyright &y& Elsevier]

Abstract: Graphene oxide and cobalt oxide nanocomposites (Co3O4/GO) are fabricated in situ as heterogeneous catalysts by the decomposition of cobalt nitrate through heat and crystal growth of Co3O4 on the surface of GO sheets in 1-hexanol solvent. The Co3O4/GO catalyst is characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM). Results show that the Co3O4/GO catalysts are large GO sheets decorated homogenously with well-dispersed Co3O4 nanoparticles. Although Co3O4 or GO alone exhibit little catalytic activity, their hybrid (Co3O4/GO) exhibits an unexpectedly high catalytic activity in the degradation of Orange II in water by advanced oxidation technology based on sulfate radicals, and 100% decomposition can be achieved in 6min. These phenomena suggest a synergistic catalytic activity of Co3O4 and GO in the hybrid. [Copyright &y& Elsevier]

Abstract: Graphene oxide (GO) nanosheets as functional material have a unique planar structure and intriguing mechanical that have attracted intensive interests recently. A method was developed for the immobilization protease on GO sheets using glutaraldehyde as cross-linking reagent. The results showed that the thermostability and reusability of immobilized protease have been obviously improved compared to the free enzyme. However, there was no significant change in optimum pH value between the free and immobilized protease. The immobilized protease exhibited good operational stability. The apparent K m and V max for free and immobilized alkaline protease were determined, and the bio-catalytic activity was not impaired by immobilization. [Copyright &y& Elsevier]

Toxoplasmosis is one of the most common foodborne diseases in the world. The objective of this study was to determine Toxoplasma gondii infection in lambs from Henan province, China. A total of 166 lamb hearts were collected from 2017 to 2019. T. gondii infection was determined by the Modified Agglutination Test (MAT) using heart juice of lambs. 11 isolates (TgSheepCHn3 - TgSheepCHn13) were obtained from samples with MAT titers ≥1:100. The rate of T. gondii isolation increased with antibody titer against T. gondii (P < 0.05). No isolate was obtained from samples with titer 1:25 and 1:50, suggesting the cut-off titer for MAT is better set at 1:100. With cut-off value of 1:100, IgG antibodies to T. gondii were found in 25.3% (42/166) of the lambs by MAT. T. gondii parasite was not found in IHC and HE-stained tissue sections of lamb hearts (0/166). Sixty-seven heart tissues with ≥1:25 MAT titers were subjected to acid pepsin digestion and detected T. gondii by PCR. Only 7.5% (5/67) of DNA amplified products were found in heart tissues by the primer TOX5/TOX8. Brain tissue cysts were observed in all mice infected with the 11 isolates at day 60 post infection, suggesting these isolates are non-lethal to mice. PCR-RFLP analysis revealed that 7 isolates belonged to ToxoDB#2, 4 isolates belonged to ToxoDB#4. This is the first isolation of ToxoDB#2 and ToxoDB#4 from lambs in China. Interestingly, none of these isolates belongs to the ToxoDB#9 that is common in China. Our results suggest that the genetic diversity and population structure of T. gondii from China maybe more abundant and magical than previous speculation. • A total of 25.3% (42/166) lambs showed sera conversion of T. gondii antibodies (cut-off titer for MAT: 1:100). • 11 viable T. gondii isolates were obtained from lambs, ToxoDB genotype #2 and #4 were identified. • The rate of isolation T. gondii increased with antibody titer against T. gondii in lamb (P < 0.05). [ABSTRACT FROM AUTHOR]

Toxoplasma gondii is widely distributed and can infect many species of warm-blooded animals, including swine. This study aimed to evaluate the prevalence of T. gondii in swines from the central of China. A total of 2798 samples, including 305 hearts, 2086 diaphragms, and 407 sera were collected from different swine in Henan Province, China. The modified agglutination test was used to detect antibodies against T. gondii in sera from jugular vein blood and heart blood (cut-off: 1:25), diaphragm juice (cut-off: 1:10). T. gondii DNA was screened from the digestive fluids of all diaphragm tissue samples and seropositive hearts, and attempt to isolate viable T. gondii strain by bioassay in mice. A total of 9.94% (278/2798) swine tested positive for T. gondii antibodies. Region, but not gender, was associated with T. gondi seropositivity in swine. T. gondii nucleic acid was not found in the tissue digestive fluids (2090 swines). Three groups of mice showed T. gondii antibodies after having been bioassayed with diaphragm samples (n = 81, which came from 2090 swine). No viable T. gondii strain was isolated from muscle of swine. This is the first large-scale survey T. gondi infection in swine from the central of China. Overall, the prevalence of viable T. gondii in swine was low. Nevertheless, T. gondii infection is present in swine from the central of China. Consumers may acquire T. gondii infection from ingestion of raw or undercooked pork. [ABSTRACT FROM AUTHOR]

Background: Sarcocystis species are intracellular protozoan parasites that can pose a threat to animal health and food safety. The aim of this study was to investigate the prevalence of infection with Sarcocystis infection in sheep from China. Results: In total, 52.51% (335/638) of tissue samples from domestic sheep contained sarcocysts through examination by light microscopy. The organisms were identified as S. tenella and S. arieticanis by molecular assays. Macroscopic S. gigantea and S. medusiformis were not found. The average sarcocysts loading was 18.07 ± 29.87 per square centimeter in the myocardium of domestic sheep. Furthermore, two specimens of argali (Ovis ammon) were examined and sarcocysts were found in the myocardium of one animal. According to the sequence of the cox1 gene of sarcocysts from argali, it was speculated as S. tenella. Conclusions: We found a high prevalence and parasite load of Sarcocystis in sheep from both central and northwest China. This report is the first to indicate that argali may be a natural intermediate host for S. tenella. [ABSTRACT FROM AUTHOR]

Abstract Myocardium and diaphragm samples of cattle (n = 521) from HeNan Province (China) were screened for Sarcocystis sarcocysts by histological examination, pepsin digestion, and molecular assays. Morphology and molecular assays were used for identification. The prevalence of Sarcocystis infection in cattle was 41.5% (216/521). Histological examination identified sarcocysts in the myocardium (49.4%, 200/405) and diaphragm (13.8%, 16/116) of cattle. Two species were identified, namely S. cruzi (41.3%, 215/521) and S. hominis (0.2%, 1/521). The findings of the present study indicate a high prevalence of S. cruzi infection in cattle from central China. Graphical abstract Unlabelled Image Highlights • The prevalence of Sarcocystis infection in cattle was 41.5% from central China. • Season and age were the risk factors of Sarcocystis infection in cattle. • The prevalence of Sarcocystis infection in cattle from China was summarized. [ABSTRACT FROM AUTHOR]

Influenza A virus (IAV) H1N1 infection is a constant threat to human health and it remains so due to the lack of an effective treatment. Since melatonin is a potent antioxidant and anti-inflammatory molecule with anti-viral action, in the present study we used melatonin to protect against H1N1 infection under in vitro and in vivo conditions. The death rate of the H1N1-infected mice was negatively associated with the nose and lung tissue local melatonin levels but not with serum melatonin concentrations. The H1N1-infected AANAT-/- melatonin-deficient mice had a significantly higher death rate than that of the WT mice and melatonin administration significantly reduced the death rate. All evidence confirmed the protective effects of melatonin against H1N1 infection. Further study identified that the mast cells were the primary targets of melatonin action, i.e., melatonin suppresses the mast cell activation caused by H1N1 infection. The molecular mechanisms involved melatonin down-regulation of gene expression for the HIF-1 pathway and inhibition of proinflammatory cytokine release from mast cells; this resulted in a reduction in the migration and activation of the macrophages and neutrophils in the lung tissue. This pathway was mediated by melatonin receptor 2 (MT2) since the MT2 specific antagonist 4P-PDOT significantly blocked the effects of melatonin on mast cell activation. Via targeting mast cells, melatonin suppressed apoptosis of alveolar epithelial cells and the lung injury caused by H1N1 infection. The findings provide a novel mechanism to protect against the H1N1-induced pulmonary injury, which may better facilitate the progress of new strategies to fight H1N1 infection or other IAV viral infections. Author summary: IAV is one of the most common respiratory pathogens, leading to acute lung injury and a high morbidity rate. Melatonin has important regulatory roles in modulating immune responses during acute inflammatory conditions. It is of great significance to explore the protection effect of melatonin against the H1N1-induced pulmonary injury. Here, we found that melatonin had essential impacts on protection against IAV infection in mice. For the first time, we proved that melatonin had the capacity to suppress the activation of mast cells and the associated inflammatory response during H1N1 infection. The molecular mechanisms involved melatonin down-regulation of gene expression for the HIF-1 pathway mediated by MT2 and inhibition of proinflammatory cytokine release from mast cells, ultimately, leading to a reduction in the migration and activation of the macrophages and neutrophils in the lung tissue. Consequently, melatonin suppressed apoptosis of alveolar epithelial cells and the lung injury caused by H1N1 infection. Our findings highlight a novel mechanism to protect against the H1N1-induced pulmonary injury, and also provide insights into the new strategies to fight IAV infections. [ABSTRACT FROM AUTHOR]

Highlights: [•] A NOx absorption equipment was developed. [•] The key parameters of the pneumatic atomizing absorption system were optimized. [•] The equipment was an atomizing stream gas–liquid reactor for removal NOx. [ABSTRACT FROM AUTHOR]