Revealing the elevation of Zn2+ in the brain of depressed mice by a ratiometric fluorescent probe with dual near-infrared emissions.

A mitochondria-targeted ratiometric fluorescent probe (Mito-Zn) was first designed and synthesized with dual emissions both located in the near-infrared region, for Zn2+ detection with high sensitivity and selectivity. By using the developed Mito-Zn, a high level of Zn2+ in the depressed mouse brain was discovered for the first time.

The Preparation of Golgi Apparatus-Targeted Polymer Dots Encapsulated with Carbon Nanodots of Bright Near-Infrared Fluorescence for Long-Term Bioimaging.

As a vital organelle in eukaryotic cells, the Golgi apparatus is responsible for processing and transporting proteins in cells. Precisely monitoring the status of the Golgi apparatus with targeted fluorescence imaging technology is of enormous importance but remains a dramatically challenging task. In this study, we demonstrate the construction of the first Golgi apparatus-targeted near-infrared (NIR) fluorescent nanoprobe, termed Golgi-Pdots. As a starting point of our investigation, hydrophobic carbon nanodots (CNDs) with bright NIR fluorescence at 674 nm (fluorescence quantum yield: 12.18%), a narrow emission band of 23 nm, and excellent stability were easily prepared from Magnolia Denudata flowers using an ultrasonic method. Incorporating the CNDs into a polymer matrix modified with Golgi-targeting molecules allowed for the production of the water-soluble Golgi-Pdots, which showed high colloidal stability and similar optical properties compared with pristine CNDs. Further studies revealed that the Golgi-Pdots showed good biocompatibility and Golgi apparatus-targeting capability. Based on these fascinating merits, utilizing Golgi-Pdots for the long-term tracking of the Golgi apparatus inside live cells was immensely successful.

Magnetic field-assisted fabrication of quasi-bilayered, multi-responsive and patternable actuators.

Quasi-bilayered actuators composed of Fe3O4-decorated graphene oxide and polyvinylidene fluoride have been fabricated in a magnetic field. The actuators could stably respond to multiple stimuli including infrared light, acetone vapour and a magnetic field. The actuator is also patternable because of the magnetism-induced spatial distribution of fillers in the matrix.

Removal of tetracycline from water by catalytic photodegradation combined with the microalga Scenedesmus obliquus and the responses of algal photosynthesis and transcription.

The antibiotic tetracycline (TC) and its degradation products (TDPs) in degradation solution present serious environmental problems, such as human health damage and ecological risk; thus further treatment is required before being released into the aquatic environment. Furthermore, their environmental impact on microalgae remains unclear. In this study, TC was degraded by photocatalysis using birnessite and UV irradiation, followed by biological purification using the microalga Scenedesmus obliquus. In addition, the photosynthetic activity and transcription of the microalgae were examined to evaluate the toxicity of TC and TDPs. The results show that photocatalytic degradation efficiency reached 92.7% after 30 min, and 11 intermediate products were detected. The microalgae achieved a high TC removal efficiency (99.7%) after 8 days. Exposure to the degraded TC solution (D) resulted in significantly lower (p < 0.05) biomass than the pure TC (T), and S. obliquus in the T treatment showed better resilience than the D treatment. Transcriptomic assays for different treatments revealed differential gene expression mainly involving the photosynthesis, ribosome, translation and peptide metabolic progresses. The up-regulation of photosynthesis-related genes and differential expression of chloroplast genes may be important for S. obliquus to acquire high photosynthetic efficiency and growth recovery when exposed to TC and TDPs. Our study provides a reference for TC removal using a combination of catalytic degradation and microalgal purification, and it is also helpful for understanding the environmental risk of TDPs in natural aquatic environments.

Metabolomics revealed the photosynthetic performance and metabolomic characteristics of Euglena gracilis under autotrophic and mixotrophic conditions.

Photosynthetic and metabolomic performance of Euglena gracilis was examined and compared under autotrophic and mixotrophic conditions. Autotrophic protozoa (AP) obtained greater biomass (about 33% higher) than the mixotrophic protozoa (MP) after 12 days of growth. AP maintained steady photosynthesis, while MP showed a remarkable decrease in photosynthetic efficiency and dropped to an extremely low level at day 12. In MP, low light absorption and photosynthetic electron transport efficiency, and high energy dissipation were reflected by the chlorophyll (chl a) fluorescence (OJIP) of the protozoa. The values of ΨO, ΦEo, and ETO/RC of MP decreased to extremely low levels, to 1/15, 1/46, and 1/9 those of AP, respectively, while DIO/RC increased to approximately 16 times that of AP. A total of 137 metabolites were showed significant differences between AP and MP. AP accumulated more monosaccharide, lipids, and alkaloids, while MP produced more amino acids, peptides, and long-chain fatty acids including poly-unsaturated fatty acids. The top nine most important enriched pathways obtained from KEGG mapping were related to ABC transporters, biosynthesis of amino acids, purine metabolism, and carbohydrate metabolism. There were significant differences between AP and MP in photosynthetic activity, metabolites, and metabolic pathways. This work presented useful information for the production of high value bioproducts in E. gracilis cultured under different nutritional conditions.

Inhibit inflammation and apoptosis of pyrroloquinoline on spinal cord injury in rat.

BACKGROUND: Pyrroloquinoline quinone (PQQ) is a redox cofactor that can participate in a variety of physiological and biochemical processes, such as anti-inflammatory, cytoprotection, anti-aging, and anti-apoptosis. PQQ plays an important protective role in the central nervous system (CNS). However, the effects of PQQ on astrocytes of the CNS and spinal cord injury (SCI) of rats is still unclear. The present study investigates the role of PQQ in inflammation, apoptosis, and autophagy after SCI in rats. And the effect of PQQ on lipopolysaccharide (LPS)-induced apoptosis and inflammation of astrocytes in vitro, to explore the neuroprotective mechanism of PQQ. METHODS: Sixty specific pathogen free (SPF) SD male rats (200-250 g) were randomly divided into Normal group, Sham group, SCI group, and SCI + PQQ group, with 15 rats in each group. BBB score, HE staining, Nissl staining, Western blot, immunofluorescence, and other methods were used for detection. RESULTS: Our results showed that PQQ could upregulate BBB score in SCI rats. In the second place, PQQ can increase the number and improve the morphology of neurons after SCI. The expression of IL-1ß, TNF-α, IL-6 was significantly decreased after PQQ treatment. And then, the ratio of B-cell lymphoma-2 (Bcl-2)/Bcl-2 associated X protein (Bax) increased significantly, and the positive signal of NeuN increased obviously after PQQ treatment. There are a large number of co-localizations between Bcl-2 and NeuN. Meanwhile, PQQ could down-regulate the expression of Active-Caspase3, and PQQ treatment could reverse the transfer of Active-Caspase3/Caspase3 from the cytoplasm to the nucleus in neurons and astrocytes after SCI. At the same time, PQQ had no significant effect on the LC3b/a ratio. PQQ could decrease the LAMP2 expression in spinal cord after injury. The expression level of phospho-Akt (p-AKT) increased after SCI and decreased after PQQ treatment. In primary astrocytes, LPS could induce the expression levels of IL-1ß, TNF-α, and IL-6, and which were inhibited by PQQ treatment at 12 hours. After treatment with LPS, the expression level of Active-Caspase3 increased, which could be reversed by PQQ treatment for 24 h. CONCLUSIONS: These results suggest that PQQ can ameliorate the motor function of hind limbs and the pathological changes of neurons and injured spinal cord after SCI, down-regulate the expressions of IL-1ß, TNF-α, and IL-6, inhibit apoptosis after SCI, and inhibit LPS-induced apoptosis and inflammation of astrocytes.

Effect of pyrroloquinoline quinone on lipopolysaccharide-induced autophagy in HAPI microglia cells.

BACKGROUND: Pyrroloquinoline quinone (PQQ) is involved in various physiological and biochemical processes, including antioxidant, cell proliferation, and mitochondrial formation. It plays a vital role in protecting neurons. However, the effect of PQQ on microglia, an inflammatory cell of the central nervous system (CNS), is still unclear. This study aimed to investigate the biological role and neuroprotective mechanism of PQQ in HAPI microglial cells exposed to lipopolysaccharide (LPS). METHODS: Western blot (WB) was used to detect apoptosis and autophagy-related molecules Bax, Bcl2, active-caspase-3, caspase-3, LC3, lysosomal associated membrane protein 2 (LAMP2), AKT, tumor necrosis factor receptor (TNFR) 1, and TNFR2 expression. The phosphatidylinositol 3-kinase (PI3K)/Akt inhibitor LY294002 was used to block the Akt pathway. WB detected the effects of PI3K on autophagy and TNFR1 and TNFR2 expression. The localization of active-caspase-3, caspase-3, LC3, LAMP2, TNFR1, and TNFR2 in cells was observed by immunofluorescence staining. The effect of PQQ on the cell cycle was examined by flow cytometry. We used 5-Ethynyl-2'-deoxyuridine (EdU) assay to detect cell proliferation. The migration ability of cells under different conditions was detected by scratch test and Transwell assay. RESULTS: Our results showed that there were different effects on the apoptosis-related molecules Bcl2/Bax and active-caspase-3/caspase in HAPI microglial cells treated with PQQ at different times. PQQ had no significant effect on the LC3b/a ratio in the early stage, which was upregulated in the later stage. The expression of LAMP2 was significantly increased in both early and late stages after PQQ treatment. At the same time, we found that PQQ can reverse the translocation of LAMP2 from the cytoplasm to the nucleus in LPS-induced HAPI microglia. After PQQ treatment, TNFR1 was significantly decreased, but TNFR2 increased in LPS-induced HAPI microglia. It may be that PQQ works through the PI3K/Akt signaling pathway to up-regulate LC3, LAMP2, and TNFR1 and down-regulate TNFR2 in LPS-induced HAPI microglia. However, PQQ has little effect on LPS-induced proliferation, cell cycle, and migration of HAPI microglia. CONCLUSIONS: In LPS-induced HAPI microglia, PQQ reduces the apoptosis level and increases that of autophagy. In addition, PQQ changes the distribution of LAMP2 in the cytoplasm and nucleus, which is regulated through the PI3K/Akt signaling pathway.

The Impact of ß-1,4-Galactosyltransferase V on Microglial Function.

ß-1,4 Galactosyltransferase V (ß-1,4-GalT V) belongs to the ß-1,4 galactosyltransferase family, which modifies proteins and plays a vital role in biological function. Our previous study revealed that ß-1,4-GalT V was expressed in the cortex and hippocampus and participated in the recovery of spatial learning and memory in rats with traumatic brain injury. However, the expression of ß-1,4-GalT V in microglia, resident immune cells in the central nervous system, and its impact on microglia in resting and lipopolysaccharide-triggered activated stages are elusive. In this study, we clarified that ß-1,4-GalT V expresses in microglia, and it regulates microglial migration, proliferation, and release of the inflammatory factors. We also observed that ß-1,4-GalT V affects the expression level of tumor necrosis factor receptor (TNFR)2 instead of TNFR1. These results strongly support the fact that ß-1,4-GalT V is involved in microglial function.

Thermal hydrolyzed food waste liquor as liquid organic fertilizer.

Thermal hydrolysis (TH) is an efficient technology for food waste (FW) management. This study investigated the nutrients released from FW under various TH temperature (140, 160, 180, 200 and 220 °C) and evaluated the feasibility of the hydrolyzed liquor (HL) as liquid organic fertilizer. The phytotoxicity and biotoxicity of HL was analyzed using wheat seed and Pseudomonas putida. Results revealed that TH could effectively solubilize FW and release nutrients (N, P and K) and organic substances. The highest content of total nitrogen (TN, 1685 mgN/L) and phosphorus (TP, 235 mgP/L) in the HL was obtained under 180 °C. The K+ was 278-293 mg/L regardless of treatment temperature. Secondary nutrients (Ca and Mg) and micro metals (Fe, Cu, Zn, Al, Co and Mn) were all detected at relatively high level, while heavy metals (As and Cd) were generally lower than 0.5 mg/L. Twenty types of free amino acid were identified and the maximum total concentration was 4965.13 mg/L. 2% HL displayed higher germination index (>80%) and enhanced root and shoot lengths. No biotoxicity was observed as confirmed by the bioassay. This study proposes a feasible method to solubilize food waste and produce liquid organic fertilizer.

Synergetic enhancement of methane production and system resilience during anaerobic digestion of food waste in ammonia-tolerant anaerobic sludge system.

The anaerobic digestion (AD) of food waste (FW) was augmented with ammonia-tolerant anaerobic sludge (ATAS). Different inoculum substrate ratios (ISR) under an initial ammonia stress of 4220 mg N/L were investigated. Results showed that the average specific methane production (SMP) of FW in the ATAS system increased by 36% compared with that in un-acclimated anaerobic sludge. SMP with ISR of 1:2.5 increased by approximately 6 times. Volatile fatty acids (VFAs) accumulation and sharp pH decline were not detected. These results revealed the high performance of ATAS in simultaneously relieving ammonia and acid stress. This improvement was attributed to multiple factors. ATAS had high ammonia tolerance and ability in conversion of acetate into methane. The equilibrium of NH3/NH4+, CO2/H2CO3/HCO3-, and CxHyCOOH/CxHyCOO- could promote VFAs and ammonia ionization, reduce the levels of free VFAs and ammonia, neutralize pH, and thus enhance the system's buffering capacity to be less susceptible to fluctuations. These results demonstrated that employing ATAS in improving AD performance and resilience from acid and ammonia inhibition is feasible and effective.

Treatment of anaerobically digested effluent from kitchen waste using combined processes of anaerobic digestion-complete nitritation-ANAMMOX based on reflux dilution.

In this study, an anaerobically digested effluent from kitchen waste with high concentrations of chemical oxygen demand (COD) and ammonia nitrogen was treated using combined processes of anaerobic digestion (AD), complete nitritation (CN), and anaerobic ammonium oxidation (ANAMMOX). The COD and nitrogen removal efficiency of each treatment unit were investigated. The feasibility of using the final treatment effluent to dilute the original wastewater was also discussed. Findings showed that as a pretreatment step, AD resulted in the decline in biodegradability and increase in NH 4 + - N concentration. CN was successfully and stably achieved for 106 days with an average nitritation rate of 95% by maintaining the dissolved oxygen at 2-3 mg/L and hydraulic retention time of 24 hr under 30 ± 1°C. High NH 4 + - N and NO 2 - - N . removal efficiencies of over 88% and 96% were attained in the following ANAMMOX reactor. The reflux of ANAMMOX-treated effluent for the dilution of raw wastewater or an influent of CN and ANAMMOX ensured the stable operation of the combined system. PRACTITIONER POINTS: Anaerobic digestion effluent of kitchen waste had low COD/ NH 4 + - N ratio and poor biodegradability. Stable and efficient nitritation was realized by controlling DO, HRT and TEMP. High NH 4 + - N and NO 2 - -N removal efficiency were obtained by ANAMMOX process. Average nitrogen removal rate of 0.94 kg N/m3 /day were obtained by ANAMMOX. Reflux dilution with the effluent guaranteed the system's successful operation.

Biochar enhanced microbial degradation of 17ß-estradiol.

Steroid estrogens (SEs), especially 17ß-estradiol (E2), can be a serious threat to the health of organisms. The removal of E2 from the natural environment is mainly carried out by microbial degradation partly mediated by biochar, which contains quinone structures. In this study, reed straw biochar samples made at four different heat treatment temperatures (HTTs) were used to mediate E2 microbial degradation by Shewanella oneidensis MR-1. The removal efficiency of E2 (95%) was highest in the presence of HTT - 500 °C biochar under anaerobic conditions after 120 h of microbial degradation. The effect of biochar on promoting microbial degradation was far more superior under anaerobic conditions than under aerobic conditions. The redox-activity and types of surface functional groups of biochar reveal that biochar can accept electrons generated by microorganisms in a timely manner. This mechanism promotes the metabolic process of cells and microbial degradation of E2 (exponential increase). Biochar particles rather than biochar-derived water-soluble organic compounds are responsible for this stimulating effect. These results highlight the impact that biochar has on microbial degradation of trace pollutants in a natural environment.

Accelerating wavefront-sensing-based autofocusing using pixel reduction in spatial and frequency domains.

The wavefront-sensing-based autofocus method can precisely determine the focal plane only with few captured images; however, the required phase retrieval, numerical wavefront propagation, and in-focus determination are often time consuming, inevitably limiting its high-speed applications. To accelerate its processing speed, the pixel-reduced wavefront-sensing-based autofocus (PRWSA) method is proposed: with field of interest selection as pixel reduction in the spatial domain and image compression as pixel reduction in the frequency domain, the wavefront with fewer pixels can be used for autofocusing, significantly decreasing the processing time. With simulations, pixel reduction criteria in both the spatial and frequency domains are first determined and tested; next certificated by experiments, the PRWSA method is proved to be well implemented for different specimens. Considering it can precisely locate the focal plane with simple setup, and accelerate the processing speed, this PRWSA method can be a potential tool for high-speed autofocusing.

Influence of three microalgal-based cultivation technologies on different domestic wastewater and biogas purification in photobioreactor.

To investigate the effects of different microalgae and culture methods on the purification of domestic wastewater and biogas, Chlorella vulgaris and Scenedesmus obliquus were selected. Three different culture methods (monoculture, microalgal-fungi cocultivation, and microalgal-activated sludge cocultivation) were used to remove nutrients from four different domestic wastewaters and remove CO2 from raw biogas in a photobioreactor. The results show that the effluent from the centrate of pretreated urban wastewater (WW4) achieved the highest nutrient and CO2 removal efficiency. Cocultivation of C. vulgaris and activated sludge achieved the highest COD, TP, and CO2 removal efficiencies of 79.27%, 81.25%, and 60.39% with WW4, respectively. Cocultivation of C. vulgaris and fungi achieved the highest TN removal efficiency of 78.46% with WW4. The contents of C, N, and P in the microalgal-activated sludge symbiont after treatment exceeded 50%, 8%, and 0.8%, respectively. Highly economically efficient energy consumption was achieved with WW4 for both C. vulgaris and S. obliquus. Microalgal-activated sludge cocultivation was identified as the optimal option for the simultaneous purification of wastewater and biogas based on its high pollution and CO2 removal efficiency. This provides a reference for the microalgal-based purification of actual domestic wastewater and raw biogas. PRACTITIONER POINTS: Nutrient and CO2 were efficiently removed by C. vulgaris with activated sludge. CO2 was removed up to 60.4% and was economically viable. Cocultivation of C. vulgaris and fungi could achieve the highest TN removal with WW4.

Refractive index sensing using the metal layer in DVD-R discs.

In recent years, grating based bio-sensors have received much attention due to their promising applications in integrated sensing devices. However, production of high quality, large scale and low cost metal gratings is still challenging. Here, we introduce an extremely simple and low cost method to fabricate metal gratings by peeling off the metal layer from a DVD-R disc. An atomic force microscope image shows that the metal layer is a high quality grating, the period and depth of which are 740 nm and 86 nm, respectively. Based on the fabricated metal grating, refractive index sensing is experimentally achieved using two configurations, where either the resonant wavelength or the modulated laser power is measured. The sensitivity of the sensor by wavelength modulation reaches as high as 637 nmRIU-1, which is comparable with or even higher than that of the existing grating coupled sensors. Our method largely reduces the cost to fabricate high quality metal gratings and will promote the development of grating based SPR sensors.

The Functional Mechanisms and Application of Electron Shuttles in Extracellular Electron Transfer.

Electron shuttles extensively exist in various environments. Some kinds of organic substances can be applied by microorganisms to produce electrons, and then the electrons can be transferred to other substances or microorganisms through electron shuttles, resulting in coexistence and interaction of diverse species of microbes. In this review, the functional mechanisms of extracellular electron transfer mediated by different electron shuttles are described. And different subtypes as well as the application of electron shuttles in microbial degradation of pollutants, microbial electricity, and the promotion of energy generation are also discussed. Summary results show that extracellular electron transfer is based on the electrogenesis microorganism with the structure of cytochromes or pili. Materials were usually used in long-distance electron transfer because of their widespread presence and abundance. Therefore, the review is beneficial to perceive the pathways of extracellular electron transfer mediated by electron shuttles and explore the contribution of different electron shuttles in extracellular electron transfer.

Subwavelength imaging by a nonlinear negative refraction lens through four wave mixing.

We propose a new approach for subwavelength imaging using a nonlinear negative refraction lens based on four wave mixing process. Here a thin metal film is implemented as the nonlinear negative refraction lens to bend the incident signal waves to negatively refracted FWM ones according to the partial phase matching along its surface. The imaging process can be described by the nonlinear optical transfer function over the entire spatial spectra including the evanescent ones. Analytical calculations and numerical simulations are performed to demonstrate the capability of such imaging. Compared with the existing techniques, our method works on non-resonant condition over a broad range of spectrum, therefore, it may open up a new avenue for super-resolution imaging applications.

Wavefront-sensing-based autofocusing in microscopy.

Massive image acquisition is required along the optical axis in the classical image-analysis-based autofocus method, which significantly decreases autofocus efficiency. A wavefront-sensing-based autofocus technique is proposed to increase the speed of autofocusing and obtain high localization accuracy. Intensities at different planes along the optical axis can be computed numerically after extracting the wavefront at defocus position with the help of the transport-of-intensity equation method. According to the focus criterion, the focal plane can then be determined, and after sample shifting to this plane, the in-focus image can be recorded. The proposed approach allows for fast, precise focus detection with fewer image acquisitions compared to classical image-analysis-based autofocus techniques, and it can be applied in commercial microscopes only with an extra illumination filter.

Synthesis and antifungal activity of 2-allylphenol derivatives against fungal plant pathogens.

2-Allylphenol (2-AP) is an effective fungicide against a number of plant pathogens, which can be metabolized and bio-transformed to four chemical compounds by Rhizoctonia cerealis. To determine if its degradation affects antifungal activity, two major metabolites derived from 2-AP including 2-(2-hydroxypropyl) phenol and 2-(3-hydroxypropyl) phenol were synthesized. Inhibition of mycelial growth of several plant pathogens by the metabolites was evaluated, and structures of two metabolites were determined by hydrogen nuclear magnetic resonance (1H NMR). Among these metabolites, only 2-(2-hydroxypropyl) phenol inhibited test pathogens effectively. EC50 values of 2-(2-hydroxypropyl) phenol for inhibition of mycelial growth of R. cerealis, Pythium aphanidermatum, Valsa mali and Botrytis cinerea ranged from 1.0 to 23.5µg/ml, which were lower than the parental fungicide 2-AP that ranged from 8.2 to 48.8µg/ml. Hyphae of R. cerealis and P. aphanidermatum treated with 2-(2-hydroxypropyl) phenol were twisted. Newly developed hyphae were slender, twisted and swollen on the tip, while old hyphae were hollow and ruptured. This is the first report indicating the formation of 2-(2-hydroxypropyl) phenol may have contributed to toxicity of 2-allylphenol in control of plant pathogens.

[Measuring Method of Cardiac Output and Its Progress].

As one of the important indexes for the diagnosis and treatment of cardiovascular diseases, cardiac output can reflect the state of cardiovascular system timely, and can play a guiding role in the treatment of related diseases. In recent years detection technology of cardiac output has caused great attention, especially minimally invasive and non-invasive methods. In this paper, the principle of non-invasive detection methods and their recent developments are described, and various detection methods are also analyzed.