In vitro and in vivo effects of 3-bromopyruvate against Echinococcus metacestodes

International audienceAbstractWhile searching for novel anti-echinococcosis drugs, we have been focusing on glycolysis which is relied on by Echinococcus for energy production and intermediates for other metabolic processes. The aim of this study was to investigate the potential therapeutic implication of glycolytic inhibitors on Echinococcus. Our results demonstrate that at an initial concentration of 40 μM, all inhibitors of glycolysis used in the current experiment [3-bromopyruvate (3-BrPA), ornidazole, clorsulon (CLS), sodium oxamate and 2,6-dihydroxynaphthalene (NA-P2)] show considerable in vitro effects against Echinococcus granulosus protoscoleces and Echinococcus multilocularis metacestodes. Among them, 3-BrPA exhibited the highest activity which was similar to that of nitazoxanide (NTZ) and more efficacious than albendazole (ABZ). The activity of 3-BrPA was dose dependent and resulted in severe ultrastructural destructions, as visualized by electron microscopy. An additional in vivo study in mice infected with E. multilocularis metacestodes indicates a reduction in parasite weight after the twice-weekly treatment of 25 mg/kg 3-BrPA for 6 weeks, compared to that of the untreated control. In particular, in contrast to ABZ, the administration of 25 mg/kg 3-BrPA did not cause toxicity to the liver and kidney in mice. Similarly, at the effective dose against Echinococcus larvae, 3-BrPA showed no significant toxicity to human hepatocytes. Taken together, the results suggest that interfering with the glycolysis of the parasite may be a novel chemotherapeutical option and 3-BrPA, which exhibited a remarkable activity against Echinococcus, may be a promising potential drug against cystic echinococcosis (CE) and alveolar echinococcosis (AE)

22.運動負荷時の血小板機能とヘモレオロジー(第636回千葉医学会例会・第3回千葉大学第三内科懇話会)

Additional file 2. Changes of residual nitrate concentration during the experiments

U-shaped Bolts Fracture Failure Analysis

AbstractLeft 1# u-shaped boltfractured when the automobile running 3766km in testing process, then 2# u-shaped bolt was repacked. Left 2# u-shaped bolt and right 3# u-shaped bolt were fractured whenthe automobile running 7778km. The failure mode and cause were analyzed by macro and micro observation, metallographic examination, hardness and tensile property testing, dimension examination.The results showed that u-shaped bolts were fatigue fracture. U-shaped bolts’ failure was related with densely distributed surface micro cracks, surface decarburization appearance, small dimension, and low strength of material

Sequential phototrophic–mixotrophic cultivation of oleaginous microalga Graesiella sp. WBG-1 in a 1000 m2 open raceway pond

Abstract Background Microalgae are an important feedstock in industries. Currently, efforts are being made in the non-phototrophic cultivation of microalgae for biomass production. Studies have shown that mixotrophy is a more efficient process for producing algal biomass in comparison to phototrophic and heterotrophic cultures. However, cultivation of microalgae in pilot-scale open ponds in the presence of organic carbon substrates has not yet been developed. The problems are heterotrophic bacterial contamination and inefficient conversion of organic carbon. Results Laboratory investigation was combined with outdoor cultivation to find a culture condition that favors the growth of alga, but inhibits bacteria. A window period for mixotrophic cultivation of the alga Graesiella sp. WBG-1 was identified. Using this period, a new sequential phototrophic–mixotrophic cultivation (SPMC) method that enhances algal biomass productivity and limits bacteria contamination at the same time was established for microalgae cultivation in open raceway ponds. Graesiella sp. WBG-1 maximally produced 12.5 g biomass and 4.1 g lipids m−2 day−1 in SPMC in a 1000 m2 raceway pond, which was an over 50% increase compared to phototrophic cultivation. The bacterial number in SPMC (2.97 × 105 CFU ml−1) is comparable to that of the phototrophic cultivations. Conclusions SPMC is an effective and feasible method to cultivate lipid-rich microalgae in open raceway ponds. Successful scale-up of SPMC in a commercial raceway pond (1000 m2 culture area) was demonstrated for the first time. This method is attractive for global producers of not only lipid-rich microalgae biomass, but also astaxanthin and β-carotene

Reversible Phase Transition for Durable Formamidinium-Dominated Perovskite Photovoltaics

Phase instability is one of the major obstacles to the wide application of formamidinium (FA)-dominated perovskite solar cells (PSCs). An in-depth investigation on relevant phase transitions is urgently needed to explore more effective phase-stabilization strategies. Herein, the reversible phase-transition process of FA1−xCsxPbI3 perovskite between photoactive phase (α phase) and non-photoactive phase (δ phase) under humidity, as well as the reversible healing of degraded devices, is monitored. Moreover, through in situ atomic force microscopy, the kinetic transition between α and δ phase is revealed to be the “nucleation–growth transition” process. Density functional theory calculation implies an enthalpy-driven α-to-δ degradation process during humidity aging and an entropy-driven δ-to-α healing process at high temperatures. The α phase of FA1−xCsxPbI3 can be stabilized at elevated temperature under high humidity due to the increased nucleation barrier, and the resulting non-encapsulated PSCs retain >90% of their initial efficiency after >1000 h at 60 °C and 60% relative humidity. This finding provides a deepened understanding on the phase-transition process of FA1−xCsxPbI3 from both thermodynamics and kinetics points of view, which also presents an effective means to stabilize the α phase of FA-dominated perovskites and devices for practical applications

The Impacts and Origins of A-site Instability in Formamidinium-Cesium Lead Iodide Perovskite Solar Cells Under Extended Operation

Improved understanding of the origins of instability during photovoltaic operation of perovskite solar cell materials must be established to overcome barriers to commercialization. In this study, we analyze the microscopic mechanisms of degradation in high-performing methylammonium free (FA0.9Cs0.1PbI3) perovskite solar cells (PSC) over 600 hours of operation under stressors inherent to PV operation, including heat, illumination, and a load while excluding atmospheric effects by testing in a water-and oxygen-free atmosphere. While the PSCs exhibit reasonable thermal stability, they show considerable performance loss under constant illumination or stable power output. Synchrotron-based nanoprobe X-ray fluorescence and X-ray beam induced current (XRF/XBIC) measurements reveal segregation of current-blocking Cs-rich phases during stress testing. The decrease in performance correlates with the resulting number density of the Cs-rich clusters, which varies by stress condition. These findings unveil cation-dependent instability in FA0.9Cs0.1PbI3 perovskites and provide a framework for understanding the energy landscape in alloy perovskites to guide the engineering of long-lived halide perovskite devices

Phase transformation barrier modulation of CsPbI3 films via PbI3− complex for efficient all-inorganic perovskite photovoltaics

Cesium lead iodide (CsPbI3) has gained great attention due to its thermal stability and appropriate bandgap (≈1.73 eV) at black (γ) phase potentially suitable for tandem solar cells. However, it is challenging to obtain CsPbI3 film with desired black phase. Herein, we fabricate kinetically favorable γ-CsPbI3 thin films by stoichiometry modulation, where in-situ 2D GIWAXS measurement was innovatively performed to illustrate the phase transition process of the precursor films, to aid a full picture study on the entire film evolution process. Conceptually different from introducing other extrinsic species, the cogenetic doping by excessive cesium iodide is found to tailor energy barriers for phase transformations during both the film formation and ageing process simultaneously. During film growth, excessive CsI affects the formation of Pb−I complex in the precursor solution, which facilitates the δ to γ phase transformation. Also, the Cs-rich resultant film could suppress γ to δ phase transformation. The corresponding CsPbI3 solar cells deliver a PCE of 16.68% without performance loss at continuous maximum power point output (MPP) for ~175 h under continuous illumination in a N2 glovebox. This work highlights the importance of precursors chemistry and provides guidelines to adjust the phase transformation barrier in CsPbI3 films without any foreign additives

Microscopic Degradation in Formamidinium-Cesium Lead Iodide Perovskite Solar Cells under Operational Stressors

The most important obstacle to widespread use of perovskite solar cells is their poor stability under operational stressors. Here, we systematically monitor the evolution of the photovoltaic performance of perovskite solar cells based on formamidinium-cesium lead iodide (FA0.9Cs0.1PbI3) for 600 h, under a series of controlled operational stressors. Although these devices exhibit reasonable thermal stability, their stability under illumination or stabilized power output (SPO) is far from commercial demands. Synchrotron-based nanoprobe X-ray fluorescence and X-ray-beam-induced current measurements reveal that current-blocking Cs-rich phases segregate during stress tests. The decrease in performance is in line with the increasing density of the Cs-rich clusters in area upon illumination. Theoretical calculations indicate that light-generated carriers provide the thermodynamic driving force for that phase segregation. Our findings correlate device performance to microscopic behavior and atomistic mechanisms and shed light on inhibiting the cation-dependent phase segregation during device operation

First molecular detection of tick-borne pathogens in dogs from Jiangxi, China

In this study, blood samples obtained from 162 dogs in Jiangxi, China, were employed in molecular screening of canine tick-borne pathogens by PCR and sequencing. Babesia spp. gene fragment was detected in 12 (7.41%) dogs. All samples were negative for Hepatozoon spp., Ehrlichia canis, Coxiella spp., Borrelia spp., Rickettsia spp. and Anaplasma platys. Species-specific PCR analysis further confirmed that 8 (4.94%) and 4 (2.47%) dogs were infected by Babesia canis vogeli and Babesia gibsoni, respectively. Based on our analyses, Babesia spp. infection in Jiangxi appeared not related to age, gender, breed, usage, activity and health status or tick infestation history of the dogs. This is the first molecular report of Babesia canis vogeli and Babesia gibsoni in dogs from Jiangxi, China