Development of central nervous system (CNS) is regulated by both intrinsic and peripheral signals. Previous studies have suggested that environmental factors affect neurological activities under both ...physiological and pathological conditions. Although there is anatomical separation, emerging evidence has indicated the existence of bidirectional interaction between gut microbiota, i.e., (diverse microorganisms colonizing human intestine), and brain. The cross-talk between gut microbiota and brain may have crucial impact during basic neurogenerative processes, in neurodegenerative disorders and tumors of CNS. In this review, we discuss the biological interplay between gut-brain axis, and further explore how this communication may be dysregulated in neurological diseases. Further, we highlight new insights in modification of gut microbiota composition, which may emerge as a promising therapeutic approach to treat CNS disorders.
Abstract
As one of the most important photocatalysts, TiO
2
has triggered broad interest and intensive studies for decades. Observation of the interfacial reactions between water and TiO
2
at ...microscopic scale can provide key insight into the mechanisms of photocatalytic processes. Currently, experimental methodologies for characterizing photocatalytic reactions of anatase TiO
2
are mostly confined to water vapor or single molecule chemistry. Here, we investigate the photocatalytic reaction of anatase TiO
2
nanoparticles in water using liquid environmental transmission electron microscopy. A self-hydrogenated shell is observed on the TiO
2
surface before the generation of hydrogen bubbles. First-principles calculations suggest that this shell is formed through subsurface diffusion of photo-reduced water protons generated at the aqueous TiO
2
interface, which promotes photocatalytic hydrogen evolution by reducing the activation barrier for H
2
(H–H bond) formation. Experiments confirm that the self-hydrogenated shell contains reduced titanium ions, and its thickness can increase to several nanometers with increasing UV illuminance.
For a long time, optical imaging of the deep brain with high resolution has been a challenge. Recently, with the advance in second near‐infrared (NIR‐II) bioimaging techniques and imaging contrast ...agents, NIR‐II window bioimaging has attracted great attention to monitoring deeper biological or pathophysiological processes with high signal‐to‐noise ratio (SNR) and spatiotemporal resolution. Assisted with NIR‐II bioimaging, the modulation of structure and function of brain is promising to be noninvasive and more precise. Herein, in this review, first the advantage of NIR‐II light in brain imaging from the interaction between NIR‐II and tissue is elaborated. Then, several specific NIR‐II bioimaging technologies are introduced, including NIR‐II fluorescence imaging, multiphoton fluorescence imaging, and photoacoustic imaging. Furthermore, the corresponding contrast agents are summarized. Next, the application of various NIR‐II bioimaging technologies in visualizing the characteristics of cerebrovascular network and monitoring the changes of the pathology signals will be presented. After that, the modulation of brain structure and function based on NIR‐II bioimaging will be discussed, including treatment of glioblastoma, guidance of cell transplantation, and neuromodulation. In the end, future perspectives that would help improve the clinical translation of NIR‐II light are proposed.
Second near‐infrared (NIR‐II) light opens up a new nonradiative and cheap opportunity for understanding brain physiological structure and modulating brain function. Given the advances in bioimaging systems and nanomaterials, nanoprobes‐assisted NIR‐II bioimaging technologies have broad application prospects in the fields of imaging brain structure, diagnosing pathological signals, and treating neurological diseases.
Harnessing the immune system to eradicate malignant cells is becoming a most powerful new approach to cancer therapy. FDA approval of the immunotherapy-based drugs, sipuleucel-T （Provenge）, ...ipilimumab （Yervoy, anti-CT- LA-4）, and more recently, the programmed cell death （PD）-I antibody （pembroliznmab, Keytruda）, for the treatment of multiple types of cancer has greatly advanced research and clinical studies in the field of cancer immunotherapy. Furthermore, recent clinical trials, using NY-ESO-l-specific T cell receptor （TCR） or CD19-chimeric antigen re- ceptor （CAR）, have shown promising clinical results for patients with metastatic cancer. Current success of cancer immunotherapy is built upon the work of cancer antigens and co-inhibitory signaling molecules identified 20 years ago. Among the large numbers of target antigens, CD19 is the best target for CAR T cell therapy for blood cancer, but CAR-engineered T cell immunotherapy does not yet work in solid cancer. NY-ESO-1 is one of the best targets for TCR-based immunotherapy in solid cancer. Despite the great success of checkpoint blockade therapy, more than 50% of cancer patients fail to respond to blockade therapy. The advent of new technologies such as next-generation sequencing has enhanced our ability to search for new immune targets in onco-immunology and accelerated the de- velopment of immunotherapy with potentially broader coverage of cancer patients. In this review, we will discuss the recent progresses of cancer immunotherapy and novel strategies in the identification of new immune targets and mu- tation-derived antigens （neoantigens） for cancer immunotherapy and immunoprecision medicine.
Millions of waste plastic express packaging bags (PEPBs) were generated with the rapid development of the express delivery industry due to the boom of electronic commerce. Waste PEPBs contain ...polyethylene (PE) material and large number of pollutants such as plasticizers and flame retardants. In this study, two effective and environmental-friendly methods were proposed to produce valuable products and remove pollutants from waste PEPBs by supercritical water degradation (SCWD) and supercritical water partial oxidation (SCWPO) treatments. Both SCWD and SCWPO treatments could effectively obtain valuable products (wax, liquid oil, CaCO3) and remove bisphenol A (BPA) and di-(2-ethylhexyl) phthalate (DEHP) from waste PEPBs. No obvious difference about the conversion could be found between SCWD and SCWPO treatments. 425 °C, 60 min, solid-to-liquid ratio of 1:20 g/mL, and V(H2O2):V(H2O) ratio of 1:3 mL/mL were the optimal conditions for the conversion of waste PEPBs by SCWD and SCWPO treatments. The maximum conversion could reach 98.13%. The produced wax and liquid oil were easily separated from each other. The produced wax mainly included long-chain olefins or long-chain alkanes, and a small amount of alcohols, ethers and aldehydes. SCWD treatment was favorable for obtaining long-chain alkenes, while SCWPO treatment was favorable for obtaining long-chain alkanes. The main chemical compounds contained in the produced liquid oil were decomposed from DEHP and BPA. DEHP was decomposed to produce 2-ethyl-1-hexanol and acetophenone. BPA was decomposed to produce 4-tert-butylphenol and other alkylated derivatives of benzene and phenol. In comparison with SCWD treatment, DEHP and BPA could be decomposed more thoroughly by SCWPO treatment.
Display omitted
•We report two effective processes for recycling of waste plastic express bags.•Resources transformation and pollutants removal could be synchronously achieved.•SCWD treatment was favorable for obtaining long-chain alkenes.•SCWPO treatment was favorable for obtaining long-chain alkanes.•Both BPA and DEHP could be effectively decomposed by SCWD and SCWPO.
In this study, subcritical water-NaOH (CW–NaOH) and subcritical water-C2H5OH (CW–C2H5OH) processes were developed for diethylhexyl phthalate (DEHP) degradation and dechlorination of polyvinyl ...chloride (PVC) waste. The introduction of NaOH or C2H5OH in subcritical water had a noticeable influence on the mechanism of DEHP degradation and dechlorination. For both CW-NaOH and CW-C2H5OH treatments, the increase in temperature could increase dechlorination efficiency (DE) of PVC. The DE of CW-NaOH is much higher than that of CW-C2H5OH under the same conditions. The DE of CW-NaOH could exceed 95% at 300 °C. Hydroxyl nucleophilic substitution was the main dechlorination mechanism in CW-NaOH, while nucleophilic substitution and direct dehydrochlorination were equally important in CW-C2H5OH. In CW-NaOH treatment, 2-ethyl-1-hexanol, benzaldehyde, and toluene were obtained by hydrolysis and reduction reactions of DEHP. Acetophenone was produced by the further cyclization, dehydrogenation and rearrangement reactions of 2-ethyl-1-hexanol. Transesterification was the main degradation pathway of DEHP in CW-C2H5OH at 300 °C. The cyclization and dehydration of 2-ethyl-1-hexanol resulted in producing a high level of ethyl-cyclohexane and 1-ethyl-cyclohexene in CW-C2H5OH at 350 °C. Furthermore, high concentration of ethyl palmitate and ethyl stearate could be prepared in CW-C2H5OH system by the strong reactivity of C2H5OH with the lubricants in PVC.
Display omitted
•We report two effective processes for DEHP degradation and dechlorination of PVC.•CW-NaOH and CW-C2H5OH have different DEHP degradation and dechlorination mechanism.•Hydrolysis and reduction were the main degradation pathways of DEHP in CW-NaOH.•Transesterification was the main degradation pathway of DEHP in CW-C2H5OH.•Nucleophilic substitution and dehydrochlorination co-existed in dechlorination.
Innate immunity is the first defense system against invading pathogens. Toll-like receptors (TLRs) are well-defined pattern recognition receptors responsible for pathogen recognition and induction of ...innate immune responses. Since their discovery, TLRs have revolutionized the field of immunology by filling the gap between the initial recognition of pathogens by innate immune cells and the activation of the adaptive immune response. TLRs critically link innate immunity to adaptive immunity by regulating the activation of antigen-presenting cells and key cytokines. Furthermore, recent studies also have shown that TLR signaling can directly regulate the T cell activation, growth, differentiation, development, and function under diverse physiological conditions. This review provides an overview of TLR signaling pathways and their regulators and discusses how TLR signaling, directly and indirectly, regulates cell-mediated immunity. In addition, we also discuss how TLR signaling is critically important in the host's defense against infectious diseases, autoimmune diseases, and cancer.
Electrochemical nitrate reduction to ammonia (eNO3RR) is a green and appealing method for ammonia synthesis, but is hindered by the multistep chemical reaction and competitive hydrogen generation. ...Herein, the synthesis of 2D SnS nanosheets with tailored interlayer spacing is reported, including both expansion and compression, through the active diatomic Pt‐Ce pairs. Taking together the experimental results, in situ Raman spectra, and DFT calculations, it is found that the compressed interlayer spacing can tune the electron density of localized p‐orbital in Sn into its delocalized states, thus enhancing the chemical affinity towards NO3− and NO2− but inhibiting hydrogen generation simultaneously. This phenomenon significantly facilitates the rate‐determining step (*NO3→*NO2) in eNO3RR, and realizes an excellent Faradaic efficiency (94.12%) and yield rate (0.3056 mmol cm−2 h−1) for NH3 at −0.5 V versus RHE. This work provides a powerful strategy for tailoring flexible interlayer spacing of 2D materials and opens a new avenue for constructing high‐performance catalysts for ammonia synthesis.
An interlayer spacing engineering of 2D SnS nanosheets is reported that involves adopting active diatomic Pt‐Ce, that tunes the electron density of localized p‐orbitals in Sn into its delocalized states, thus significantly improving NO3−‐to‐NH3 conversion for both activity and selectivity.
Model predictive current control of permanent magnet synchronous motor(PMSM), which inherits from the vector control framework, has become a promising control strategy because of its simple structure ...and fast dynamic response. In order to protect the stator current prediction model from the influence of mismatched parameters, a simple and robust predictive current control with stator current predictor and target-oriented cost function (abbreviated as SCP-TOSF-PCC) is proposed in this paper. The feedback mechanism is introduced into the prediction equation in the discrete domain, and its design principle and stability analysis are also described in detail. In addition, different from the traditional cost function design method which is constructed by the tracking errors of stator current, this paper proposes a direct target-oriented cost function, which takes the average pulsations of <inline-formula> <tex-math notation="LaTeX">{d} </tex-math></inline-formula>-axis current and <inline-formula> <tex-math notation="LaTeX">{q} </tex-math></inline-formula>-axis current as the judge index. The design method of this cost function takes into account the influence of historical values on the voltage vector selection. The experimental results show that compared with the traditional methods, the proposed method has better dynamic, steady-state and robust performance.
PDF
