Pinctada martensii Hydrolysate Modulates the Brain Neuropeptidome and Proteome in Diabetic (db/db) Mice via the Gut-Brain Axis.

Pinctada martensii hydrolysate (PMH) has been proved to have the effect of ameliorating disorders of glucose and lipid metabolism in db/db mice, but the mechanism of its hyperglycemia effect is still unclear. Bacterial communities in fecal samples from a normal control group, a diabetic control group, and a PMH-treated diabetes mellitus type 2 (T2DM) group were analyzed by 16S gene sequencing. Nano LC-MS/MS was used to analyze mice neuropeptides and proteomes. The 16S rDNA sequencing results showed that PMH modulated the structure and composition of the gut microbiota and improved the structure and composition of Firmicutes and Bacteroidetes at the phylum level and Desulfovibrionaceae and Erysipelatoclostridiaceae at the family level. Furthermore, the expressions of functional proteins of the central nervous system, immune response-related protein, and proteins related to fatty acid oxidation in the brain disrupted by an abnormal diet were recovered by PMH. PMH regulates the brain neuropeptidome and proteome and further regulates blood glucose in diabetic mice through the gut-brain axis. PMH may be used as a prebiotic agent to attenuate T2DM, and target-specific microbial species may have unique therapeutic promise for metabolic diseases.

Diatomite-Based Recyclable and Green Coating for Efficient Radiative Cooling.

Radiative cooling is a promising strategy to address energy challenges arising from global warming. Nevertheless, integrating optimal cooling performance with commercial applications is a considerable challenge. Here, we demonstrate a scalable and straightforward approach for fabricating green radiative cooling coating consisting of methyl cellulose matrix-random diatomites with water as a solvent. Because of the efficient scattering of the porous morphology of diatomite and the inherent absorption properties of both diatomite and cellulose, the aqueous coating exhibits an excellent solar reflectance of 94% in the range of 0.25-2.5 µm and a thermal emissivity of 0.9 in the range of 8-14 µm. During exposure to direct sunlight at noon, the obtained coating achieved a maximum subambient temperature drop of 6.1 °C on sunny days and 2.5 °C on cloudy days. Furthermore, diatomite is a naturally sourced material that requires minimal pre-processing, and our coatings can be prepared free from harmful organic compounds. Combined with cost-effectiveness and environmental friendliness, it offers a viable path for the commercial application of radiative cooling.

NIR-II-activated biocompatible hollow nanocarbons for cancer photothermal therapy.

Photothermal therapy has attracted extensive attentions in cancer treatment due to its precise spatial-temporal controllability, minimal invasiveness, and negligible side effects. However, two major deficiencies, unsatisfactory heat conversion efficiency and limited tissue penetration depth, hugely impeded its clinical application. In this work, hollow carbon nanosphere modified with polyethylene glycol-graft-polyethylenimine (HPP) was elaborately synthesized. The synthesized HPP owns outstanding physical properties as a photothermal agent, such as uniform core-shell structure, good biocompatibility and excellent heat conversion efficiency. Upon NIR-II laser irradiation, the intracellular HPP shows excellent photothermal activity towards cancer cell killing. In addition, depending on the large internal cavity of HPP, the extended biomedical application as drug carrier was also demonstrated. In general, the synthesized HPP holds a great potential in NIR-II laser-activated cancer photothermal therapy.

[Preventing role of warmth-promotion needling in reducing intracellular Ca2＋ overload of in vitro hippocampal neuronal cells of vascular dementia rats].

OBJECTIVE: To investigate the underlying mechanisms of warming-promotion needling (WPN) for vascular dementia (VD) by observing its effect on the expression of L-type calcium channel current (Ica.L), changes of intracellular [Ca2＋]i in neurons and pathomorphological changes of brain in VD rats. METHODS: One hundred and eight male SD rats were randomized into normal control, model, medication, WPN, uniform reinforcing-reducing needling (URRN), and needle-twirling groups (n＝18 in each group). The VD model was established by repeated occlusion and reperfusion of the bilateral common carotid arteries. Rats of the medication group were treated by gavage of Nimodipine twice a day for 14 days. For rats of the 3 acupuncture groups, WPN or URRN or needle-twirling was applied to "Dazhui" (GV14), "Baihui"(GV20) and "Shuigou"(GV26) for 30 min, once a day for 14 days. Changes of Ica.L in hippocampal neurons were observed by whole-cell patch clamp technique, and levels of [Ca2＋]i in neuronal cells of living brain slice of hippocampal CA1 area were observed by laser confocal microscope. Histopathological changes of hippocampal CA1 area were observed under light microscope after H．E. stain. RESULTS: Compared with the normal control group, the current density of Ica.L, and the intracellular[Ca2＋]i levels were significantly increased (P<0.05), and the I-V curves of Ica.L was apparently shifted down in the model group. In comparison with the model group, the current density of Ica.L was obviously reduced (P<0.05), the I-V curves of Ica.L shifted up and the intracellular Ca2＋ content notably decreased in the medication, WPN, URRN and needle-twirling groups (P<0.05). The effect of WPN was significantly superior to those of URRN and needle-twiiling (P<0.05). H．E. stain showed a reduction in the number of hippocampal neurons, dilation of intercellular space, swelling of cell body, karyopyknosis, disordered arrangement and increased number of gliacytes in the model group, which was apparently milder in the medication and 3 acupuncture groups (the WPN group in particular). CONCLUSION: The WPN can reduce Ica.L current density and [Ca2＋]i content of hippocampal neurons in brain slices of VD rats, which may contribute to its effect in relieving VD by suppressing calcium overload.

Biocompatible Mesoporous Hollow Carbon Nanocapsules for High Performance Supercapacitors.

A facile and general method for the controllable synthesis of N-doped hollow mesoporous carbon nanocapsules (NHCNCs) with four different geometries has been developed. The spheres (NHCNC-1), low-concaves (NHCNC-2), semi-concaves (NHCNC-3) and wrinkles (NHCNC-4) shaped samples were prepared and systematically investigated to understand the structural effects of hollow particles on their supercapacitor performances. Compared with the other three different shaped samples (NHCNC-1, NHCNC-2, and NHCNC-4), the as-synthesized semi-concave structured NHCNC-3 demonstrated excellent performance with high gravimetric capacitance of 326 F g-1 (419 F cm-3) and ultra-stable cycling stability (96.6% after 5000 cycles). The outstanding performances achieved are attributed to the unique semi-concave structure, high specific surface area (1400 m2 g-1), hierarchical porosity, high packing density (1.41 g cm-3) and high nitrogen (N) content (up to 3.73%) of the new materials. These carbon nanocapsules with tailorable structures and properties enable them as outstanding carriers and platforms for various emerging applications, such as nanoscale chemical reactors, catalysis, batteries, solar energy harvest, gas storage and so on. In addition, these novel carbons have negligible cytotoxicity and high biocompatibility for human cells, promising a wide range of bio applications, such as biomaterials, drug delivery, biomedicine, biotherapy and bioelectronic devices.

Highly efficient solar seawater desalination with environmentally friendly hierarchical porous carbons derived from halogen-containing polymers.

Desalination of seawater using solar energy is a promising solution to the global freshwater shortage. Ultrahigh surface area (up to 1740 m2 g-1) hierarchical porous carbons (HPC) have been prepared by the carbonization of precursors derived from the room temperature dehalogenation of low cost, widely available polyvinyl chloride (PVC) with simple, low cost, environmentally friendly processes. The broad hierarchical pores (from 2 nm to 20 µm) facilitate and ensure fast water and vapor transportation. Flexible photothermal steam generation devices were successfully fabricated with these hierarchical porous carbons on hydrophilic ultrathin (200 µm) paper. An evaporation rate record of 7.87 kg m-2 h-1 and high energy conversion of 95.8% have been obtained under the concentrated solar intensity of 5 kW m-2. Our research leads to a new approach to converting halogenated plastics into environmentally friendly and useful porous carbon materials by simple, low-cost processes. It establishes and validates the concept of creating a sustainable and economic pathway to simultaneously recycle halogenated polymers, harvest solar energy and produce clean freshwater.

Effect of water presence on choline chloride-2urea ionic liquid and coating platings from the hydrated ionic liquid.

In the present study, hygroscopicity of the choline chloride-urea (ChCl-2Urea) ionic liquid (IL) was confirmed through Karl-Fisher titration examination, indicating that the water content in the hydrated ChCl-2Urea IL was exposure-time dependent and could be tailored by simple heating treatment. The impact of the absorbed water on the properties of ChCl-2Urea IL, including viscosity, electrical conductivity, electrochemical window and chemical structure was investigated. The results show that water was able to dramatically reduce the viscosity and improve the conductivity, however, a broad electrochemical window could be persisted when the water content was below ~6 wt.%. These characteristics were beneficial for producing dense and compact coatings. Nickel (Ni) coatings plating from hydrated ChCl-2Urea IL, which was selected as an example to show the effect of water on the electroplating, displayed that a compact and corrosion-resistant Ni coating was plated from ChCl-2Urea IL containing 6 wt.% water doped with 400 mg/L NA at a moderate temperature. As verified by FTIR analysis, the intrinsic reason could be ascribed that water was likely linked with urea through strong hydrogen bond so that the water decomposition was suppressed during plating. Present study may provide a reference to prepare some similar water-stable ILs for plating.

Tunable growth of silver nanobelts on monolithic activated carbon with size-dependent plasmonic response.

Silver is one of the most important materials in plasmonics. Tuning the size of various silver nanostructures has been actively pursued in the last decade. However, silver nanobelt, a typical one-dimensional silver nanostructure, has not been systematically studied as to tuning its size for controllable plasmonic response. Here we show that silver nanobelts, with mean width ranging from 45 to 105 nm and thickness at ca. 13 nm, can grow abundantly on monolithic activated carbon (MAC) through a galvanic-cell reaction mechanism. The widths of silver nanobelts are positively correlated to the growth temperatures. The width/thickness ratio of the silver nanobelts can be adjusted so that their transversal plasmonic absorption peaks can nearly span the whole visible light band, which endows them with different colours. This work demonstrates the great versatility of a simple, green and conceptually novel approach in controlled synthesis of noble metal nanostructures.

Morphosynthesis of cubic silver cages on monolithic activated carbon.

Cubic silver cages were prepared on monolithic activated carbon (MAC) pre-absorbed with Cl(-), SO4(2-), or PO4(3-) anions. Silver insoluble salts served as templates for the morphosynthesis of silver cages. The silver ions were reduced by reductive functional groups on MAC micropores through a galvanic cell reaction mechanism.

Full-color CO2 gas sensing by an inverse opal photonic hydrogel.

CO2 gas sensing is of great importance because of the impact of CO2 on global climate change. Here, utilizing an inverse opal hydrogel, we describe a CO2 gas sensing method that allows highly sensitive and selective detection over a wide concentration range. The CO2 sensor is specific, quantitative, interference tolerant and without the need for special instruments.

Green "planting" nanostructured single crystal silver.

Design and fabrication of noble metal nanocrystals have attracted much attention due to their wide applications in catalysis, optical detection and biomedicine. However, it still remains a challenge to scale-up the production in a high-quality, low-cost and eco-friendly way. Here we show that single crystalline silver nanobelts grow abundantly on the surface of biomass-derived monolithic activated carbon (MAC), using [Ag(NH3)2]NO3 aqueous solution only. By varying the [Ag(NH3)2]NO3 concentration, silver nanoplates or nanoflowers can also be selectively obtained. The silver growth was illustrated using a galvanic-cell mechanism. The lowering of cell potential via using [Ag(NH3)2]⁺ precursor, together with the AgCl crystalline seed initiation, and the releasing of OH⁻ in the reaction process, create a stable environment for the self-compensatory growth of silver nanocrystals. Our work revealed the great versatility of a new type of template-directed galvanic-cell reaction for the controlled growth of noble metal nanocrystals.

Wettability gradient colorimetric sensing by amphiphilic molecular response.

Herein we present a highly sensitive sensing method combining amphiphilic molecules and wettability gradient photonic hydrogels for molecular recognition and chemical sensing applications. These wettability gradient photonic films exhibit low analyte amount, fast response, as well as interference resistance, which enable them for applications in forgery detection and visual determination of analyte concentrations.

Photonic crystal coupled plasmonic nanoparticle array for resonant enhancement of light harvesting and power conversion.

Photonic crystal coupled with plasmonic nanoparticle arrays to form a periodic plasmonic architecture was prepared by loading Au nanoparticles inside the inverse opal TiO(2) film. The visible and near infrared light absorption was increased by 62% and the overall light-to-electricity conversion yield was thus increased by 41% compared with the control test.

Independent multifunctional detection by wettability controlled inverse opal hydrogels.

Utilizing the wettability of inverse opal hydrogels, we report a new strategy to construct photonic hydrogels with multiple types of reliable signals, such as non-wetting (transparent), image contrast (weak color) with shifts of diffraction maximum (bright color), developing optical sensors for multifunctional detection.

Tunable growth of nanodendritic silver by galvanic-cell mechanism on formed activated carbon.

Well-defined silver dendritic nanostructures have been prepared in large quantities in an ambient environment using formed activated carbon (FAC) only. A reasonable mechanism (step 1: reduction by surface reductive groups; step 2: growing in the form of a galvanic cell) is suggested.