RESUMEN
The present study introduces a novel fungus, Cystoderma yongpingense, which was identified in the southwestern region of China. The new species is characterized by a pileus that ranges in color from light orange-red to orange-red; the pileus has a wrinkled surface and is accompanied by a persistent annulus that is membranous and floccose-scaly. Above the annulus, the color transitions from white to yellowish brown. This proposal is substantiated through analyses encompassing both morphological characteristics and phylogenetic relationships. The phylogenetic position of the newly discovered species has been further corroborated through comprehensive maximum likelihood and Bayesian sequence analyses of the ITS + nrLSU DNA regions. Additionally, the technical description of C. yongpingense is enhanced by detailed illustrations and comparative studies with species that are closely related.
RESUMEN
Methanol (MeOH) oxidation reaction (MOR) at Pt electrodes under potentiostatic conditions has been investigated by electrochemical in situ FTIR spectroscopy (FTIRS) in attenuated-total-reflection configuration under controlled flow conditions in 0.1 M HClO(4) with 2 M MeOH, where the mass transport effects are largely eliminated using a flow cell. Our results reveal that (i) at constant potentials, the methanol dehydrogenation rate decreases while the CO(ad) oxidation rate increases with the accumulation of CO(ad) until the maximum CO(ad) coverage (ca. 0.5 ML i.e., the steady state) is reached; (ii) at fixed CO(ad) coverage, the rates for MeOH decomposition to CO(ad) and CO(ad) oxidation increases with potential from 0.3 to 0.7 V (vs. RHE), with Tafel slopes for MeOH dehydrogenation of ca. 440 ± 30 mV/dec, which is independent of CO(ad) coverage; (iii) the current efficiency of the CO pathway in MOR at 0.6 and 0.7 V is below 20% and it decreases toward higher potentials. The mechanisms as well as the potential induced change in the kinetics of different pathways involved in MOR are briefly discussed.
RESUMEN
The effects of temperature, CO(ad) surface coverage, and electrode potential on the desorption of CO(ad) from Pt film electrodes in 0.5 M H(2)SO(4) have been investigated by electrochemical in situ FTIR spectroscopy under an attenuated-total-reflection configuration (EC-FTIRS). The major findings are: (i) When theta(rel)>or= 0.53 (theta(CO) is the relative CO(ad) coverage), CO(ad) desorption takes place at T > 40 degrees C (as confirmed by the decrease in both of the C-O(L) stretching frequency as well as the CO(ad) stripping charge), and when theta(rel) is below 0.39, no CO(ad) desorption is observed at temperatures up to 70 degrees C; (ii) A slight increase in CO(ad) desorption rate with electrode potential from 0.1 to 0.3 V and fast adsorption/desorption equilibrium in solution saturated with CO are observed; (iii) From the temperature-dependent changes in CO(ad) surface coverage, the activation energies for CO(ad) desorption are determined to be in the range of 104 and 117 kJ mol(-1), which increases with decreasing CO(ad) coverage.
RESUMEN
BACKGROUND: Neospora caninum is an obligate intracellular protozoan that causes neosporosis, N. caninum infection is a major cause of abortion in cattle worldwide. Currently, specific treatment for neosporosis is not available. The NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome is a cytoplasmic protein complex that plays an important role in host defense against N. caninum infection, but the underlying mechanisms are poorly understood. METHODS: The reactive oxygen species (ROS) inhibitor and the ROS inducer, wild-type (WT) and NLRP3-deficient peritoneal macrophages or mice were used to investigate the role of ROS in NLRP3 inflammasome activation and controlling parasite burdens. ROS production, cell death and cell viability, production of inflammasome-mediated IL-1ß or IL-18, cleavage of caspase-1 and NLRP3 expression, as well as parasite burdens were detected. RESULTS: In vitro, N. caninum induced ROS generation in a dose-dependent manner in peritoneal macrophages. The pretreatment of ROS inhibitor N-acetyl-L-cysteine (NAC) significantly attenuated N. caninum-induced ROS production, LDH release, IL-1ß secretion and NLRP3 expression, whereas N. caninum proliferation was notably increased. In contrary, the ROS inducer pyrogallol (PG) significantly enhanced ROS production and NLRP3 inflammasome activity and decreased the parasite burden in N. caninum-infected peritoneal macrophages. NADPH-dependent ROS-mediated NLRP3 inflammasome activation induced by N. caninum can also be confirmed by using the NADPH oxidase inhibitor diphenyleneiodonium chloride (DPI). However, the NAC or DPI pre-treatment or PG treatment did not significantly alter N. caninum-induced inflammasome activities and parasite proliferation in Nlrp3-/- peritoneal macrophages. In vivo, IL-18 releases in serum and parasite burdens in peritoneal exudate cells were significantly increased in PG-treated WT mice after infection with N. caninum; however, IL-18 productions and parasite burdens were not changed in PG-treated Nlrp3-/- mice. Furthermore, PG treatment in WT mice infected with N. caninum significantly decreased the mortality, weight loss and parasite burdens in tissues and histopathological lesions. CONCLUSIONS: Neospora caninum-induced NADPH-dependent ROS generation plays an important role in NLRP3 inflammasome activation and controlling parasites. The ROS inducer PG can control N. caninum infection mainly by promoting NLRP3 inflammasome activation. ROS-mediated NLRP3 inflammasome axis can be a potential therapeutic target for neosporosis.