Integrated metabolic profiles and microbial communities to reveal the beneficial effect of red pitaya on early constipation.

Pitaya is a well-known fruit widely cultivated in tropical and subtropical tropical regions, and is characterized by its flesh colour into red, white, and yellow pitaya. Red pitaya has dark red flesh and is the preferred choice among consumers due to its superior taste compared to other varieties. Red pitaya has been known to cause diarrhoea, and studies have reported that pitaya does this by drawing moisture into the intestines, resulting in defecation. However, the exact mechanism of action is still unclear. In this study, mass spectrometry was employed to identify small molecular compounds in red pitaya powder, and a loperamide hydrochloride-induced early constipation mouse model was used to assess the efficacy of red pitaya. 16S rDNA and non-targeted metabolomics techniques were used to systematically reveal the regulatory characteristics of the intestinal flora and to identify the intestinal metabolites associated with constipation. The results showed that 44 novel small molecular compounds were identified from red pitaya powder, including a variety of phenolic acids and flavonoids. Pathological results showed that administration of red pitaya powder at a high dose (1000 mg kg-1) significantly ameliorated the abnormal expansion of intestinal goblet cells observed in the early stages of constipation. In addition, early constipation increased metabolites such as serotonin and 5-hydroxytryptophol, which were normalized following the ingestion of red pitaya powder. Furthermore, Erysipelatoclostridium, Parasutterella, and other abnormal gut microbiota associated with early constipation returned to healthy levels after the ingestion of red pitaya powder. Finally, significant correlations were observed between the expression of 33 different serum metabolites and the abundance of eight kinds of intestinal flora. Consequently, red pitaya holds potential as a safe food supplement for the prevention or amelioration of early-stage constipation.

Copper(I)-Catalyzed Indolyl Ynamide Oxidation/Dearomatization: Divergent and Regioselective Synthesis of Valuable Indoline Scaffolds.

A highly convenient copper(I)-catalyzed oxidation-initiated cyclopropanation of indolyl ynamide for the rapid construction of indole-fused cyclopropane-lactams is described, which represents, to the best of our knowledge, the first non-noble-metal-catalyzed indolyl ynamide oxidation/dearomatization by the in situ generated α-oxo copper carbenes. Compared to hydrazone and diazo, the use of alkynes as carbene precursors allows cyclopropanation to occur under a safe and convenient pathway. Moreover, this transformation can lead to the divergent synthesis of pentacyclic spiroindolines involving the reversal of ynamide regioselectivity by engineering substrate structures.

Tissue expression of porcine transient receptor potential mucolipin protein channels and their differential responses to porcine reproductive and respiratory syndrome virus infection in vitro.

Introduction: Porcine reproductive and respiratory syndrome virus (PRRSV) infection results in a serious disease, posing a huge economic threat to the global swine industry. The transient receptor potential mucolipin proteins (TRPMLs) have been shown to be strongly associated with virus infection and other physiological processes in humans, but their tissue distribution and responses to PRRSV in pigs remain unknown. Material and Methods: Quantitative reverse-transcription PCR analysis was undertaken to determine the optimal primer for TRPML expression detection and for quantifying that expression individually in different pig tissue samples. Meat Animal Research Center 145 (MARC-145) monkey kidney cells and the TRPML-specific activator mucolipin synthetic agonist 1 (ML-SA1) were used to reveal the relationship between TRPML and PRRSV-2 infection. Results: The best primers for each TRPML gene used in a fluorescence-based quantitative method were identified and TRPML1 was found to be highly expressed in the kidneys and liver of pigs, while TRPML2 and TRPML3 were observed to be primarily expressed in the kidney and spleen tissues. The expression of TRPML2 was upregulated with the rise in PRRSV-2 infection titre but not the expression of TRPML1 or TRPML3, and ML-SA1 inhibited PRRSV-2 in a dose-dependent manner. Conclusion: Our research revealed the gene expression of TRPMLs in pigs and identified that TRPML channels may act as key host factors against PRRSV infection, which could lead to new targets for the prevention and treatment of pig infectious diseases.

Schizosthetus Athias-Henriot, 1982 (Mesostigmata: Parasitidae): the description of a new species from China.

A new species, Schizosthetus baixuelii sp. nov., is described based on females from Ningxia Hui Autonomous Region, China. A key to the known species of the genus is presented.

Cascaded p-d Orbital Hybridization Interaction in Ultrathin High-Entropy Alloy Nanowires Boosts Complete Non-CO Pathway of Methanol Oxidation Reaction.

Designing high efficiency platinum (Pt)-based catalysts for methanol oxidation reaction (MOR) with high "non-CO" pathway selectivity is strongly desired and remains a grand challenge. Herein, PtRuNiCoFeGaPbW HEA ultrathin nanowires (HEA-8 UNWs) are synthesized, featuring unique cascaded p-d orbital hybridization interaction by inducing dual p-block metals (Ga and Pb). In comparison with Pt/C, HEA-8 UNWs exhibit 15.0- and 4.2-times promotion of specific and mass activity for MOR. More importantly, electrochemical in situ FITR spectroscopy reveals that the production/adsorption of CO (CO* ) intermediate is effectively avoided on HEA-8 UNWs, leading to the complete "non-CO" pathway for MOR. Theoretical calculations demonstrate the optimized electronic structure of HEA-8 UNWs can facilitates a lower energy barrier for the "non-CO" pathway in the MOR.

Impacts of climate change and host plant availability on the potential distribution of Bradysia odoriphaga (Diptera: Sciaridae) in China.

BACKGROUND: Chinese chives (Allium tuberosum Rottler ex Sprengel) are favored by consumers because of its delicious taste and unique fragrance. Bradysia odoriphaga (Diptera: Sciaridae) is a main pest that severely harms Chinese chives and other Liliaceae's production. Climate change may change the future distribution of B. odoriphaga in China. In this study, the CLIMEX was employed to project the potential distribution of B. odoriphaga in China, based on China's historical climate data (1987-2016) and forecast climate data (2021-2100). RESULTS: Bradysia odoriphaga distributed mainly between 19.8° N-48.3° N and 74.8° E-134.3° E, accounting for 73.25% of the total mainland area of China under historical climate conditions. Among them, the favorable and highly favorable habitats accounted for 30.64% of the total potential distribution. Under future climate conditions, B. odoriphaga will be distributed mainly between 19.8° N-49.3° N and 73.8° E-134.3° E, accounting for 84.89% of China's total mainland area. Among them, the favorable and highly favorable habitats will account for 35.23% of the total potential distribution, indicating an increase in the degree of fitness. Areas with relatively appropriate temperature and humidity will be more suitable for the survival of B. odoriphaga. Temperature was a more important determinant of the climatic suitability of the pest B. odoriphaga than humidity. Host plants (Liliaceae) availability also had impact on climate suitability in some regions. CONCLUSIONS: These projected potential distributions will provide supportive information for monitoring and early forecasting of pest outbreaks, and to reduce future economic and ecological losses. © 2024 Society of Chemical Industry.

The augmentation of cytotoxic immune cell functionality through physical exertion bolsters the potency of chemotherapy in models of mammary carcinoma.

BACKGROUND: Mammary carcinoma, a pervasive and potentially lethal affliction, is conjectured to be profoundly influenced by physical exercise, both in prophylaxis and therapeutic contexts. This study endeavors to explore the repercussions of exercise training on the progression of mammary carcinoma, particularly the mechanisms by which the amalgamation of an exercise regimen and doxorubicin induces tumor cell apoptosis. METHODS: Female BALB/c mice were categorized into four distinct groups: A sedentary group (SED), an exercise group (Ex), a doxorubicin group (Dox, 5 mg/kg), and a combined treatment group (Dox + Ex). The exercise training lasted for 21 days and included aerobic rotarod exercise and resistance training. The impact of exercise training on tumor growth, immune cell proportions, inflammatory factor levels, and cell apoptosis pathway was assessed. RESULTS: Exercise training significantly curtailed tumor growth in a mouse model of breast cancer. Both the Ex and Dox groups exhibited significant reductions in tumor volume and weight (p < 0.01) in comparison to the SED group, while the Dox + Ex group had a significantly lower tumor volume and weight than the Dox group (p < 0.01). Exercise training also significantly increased the proportion of NK and T cells in various parts of the body and tumor tissue, while decreasing tumor blood vessels density. Exercise training also increased IL-6 and IL-15 levels in the blood and altered the expression of apoptosis-related proteins in tumor tissue, with the combined treatment group showing even more significant changes. CONCLUSIONS: Physical training improves the effectiveness of doxorubicin in treating breast cancer by activating cytotoxic immune cells, releasing tumor suppressor factors, and initiating mt-apoptosis, all while mitigating the adverse effects of chemotherapy.

Integrated multi-omics profiling highlights the benefits of resveratrol hydroxypropyl-ß-cyclodextrin inclusion complex for A53T transgenic mice through the microbiota-gut-brain axis.

Parkinson's disease (PD) is a neurological disorder characterized by motor and gastrointestinal dysfunctions. Resveratrol is a potent antioxidant and anti-inflammatory phytoalexin known for its health-promoting benefits. However, little is known about its potential in treating PD by modulating the microbial gut-brain axis, and its clinical application has been limited due to poor water solubility, rapid metabolism, and limited systemic bioavailability. Our study aimed to evaluate the therapeutic potential of RHSD, a resveratrol-cyclodextrin inclusion complex, in treating PD through the gut-brain axis in human SNCA-transgenic (A53T) mice PD models. Building on our previous study, we prepared RHSD and compared its efficacy with uncoated resveratrol for PD treatment. The study results demonstrated that RHSD exhibited several advantages in improving motor function, alleviating cognitive impairment, restoring intestinal barrier function, and inhibiting neuropathy. Subsequently, a series of analyses, including fecal microbiota metagenomic sequencing, non-target metabolic assays, host transcriptome sequencing, and integrative analysis were performed to reveal the potential therapeutic pathways of RHSD in A53T mice. The metagenomic sequencing results indicated a significant increase in the levels of Lactobacillus murinus, Lactobacillus reuteri, Enterorhabduscaecimuris, Lactobacillus taiwanensis, and Lactobacillus animals following RHSD administration. Furthermore, metabolomics profiling showed that the levels of gut microbiome metabolites were reversed after RHSD treatment, and differential metabolites were significantly correlated with motor function and intestinal function in PD mice. The integrated analysis of microbial metabolites and host transcriptomics suggested that abnormal amino acid metabolism, mitochondrial dysfunction, oxidative stress, and neuroinflammation in the PD model were associated with the diffusion of abnormal metabolites. This study illustrates the profound impact of RHSD administration on rectifying gut microbiota dysbiosis and improving the A53T mouse model. Notably, we observed significant alterations in the proliferation and metabolism of multiple probiotic strains of Lactobacillus. Furthermore, our research supports the hypothesis that microbiota-related metabolites may regulate the transcription of host genes, including dopamine receptors and calcium stabilization. Consequently, our findings underscore the potential of RHSD as a promising therapeutic candidate for the treatment of PD through the modulation of several signaling pathways within the microbiota-gut-brain axis.

Black carp RIOK3 suppresses MDA5-mediated IFN signaling in the antiviral innate immunity.

In mammals, right open reading frame kinase 3 (RIOK3) is related with cancer development and immune regulation. To explore the role of teleost RIOK3 in the antiviral innate immunity, the homolog of RIOK3 (bcRIOK3) from black carp (Mylopharyngodon piceus) has been cloned and characterized in this study. Sequence analysis revealed that bcRIOK3 is conserved in vertebrates. The transcription of bcRIOK3 varied in host cells in response to the stimulation of spring viremia of carp virus (SVCV), poly (I:C), and LPS. Immunoblotting (IB) and immunofluorescence (IF) assays identified bcRIOK3 as a cytoplasmic protein with a molecular weight of ∼60 kDa. It was interesting that bcRIOK3 knockdown led to the decreased basal mRNA levels of IFNa, IFNb and Viperin; however, triggered obviously higher mRNA levels of the above genes after viral infection and enhanced host resistance to SVCV. Like its mammalian counterpart, bcRIOK3 overexpression in EPC cells showed a significant inhibitory effect on black carp MDA5 (bcMDA5)-mediated transcription of interferon promoters and antiviral activity. Co-immunoprecipitation and immunofluorescent assays identified the association between bcRIOK3 and bcMDA5. Further analysis revealed that bcRIOK3 enhanced the K48-linked ubiquitination and proteasome-dependent degradation of bcMDA5, and it weakened the oligomerization of bcMDA5 under poly (I:C) stimulation. In summary, our data conclude that RIOK3 dampens MDA5-mediated IFN signaling by promoting its degradation in black carp, which provide new insights into the regulation of IFN signaling in teleost.

Two-birds with one stone: Improving both cathode and anode electrochemical performances via two-dimensional Te-CoTe2/rGO ultrathin nanosheets as sulfur hosts in lithium-sulfur batteries.

A Te-doped CoTe2 film could be grown in situ on reduced graphene oxide (rGO) to develop a Te-CoTe2/rGO composite with an ultrathin layered structure, which has multiple protective effects on both the sulfur positive electrode and lithium negative electrode in lithium sulfur (Li-S) batteries. The Te-CoTe2/rGO composite as a sulfur host not only shows a strong adsorbing ability for lithium polysulfides (LiPSs) but can also accelerate the conversion reaction of active material sulfur during the charging/discharging process. More importantly, this host can turn the shuttle effect from an unfavorable factor to a favorable factor, which could improve the electrochemical performance of the lithium anode with uniform lithium plating/stripping resulting from the intermediate polytellurosulfide species (Li2TexSy), which could be generated on the cathode surface via Te reacting with soluble Li2Sn (4 ≤ n ≤ 8). As a result, the S@Te-CoTe2/rGO cathode shows a discharge capacity of 970.0 mA h g-1 in the first cycle at 1 C and retains a high capacity of 545.5 mA h g-1 after 1000 cycles, corresponding to a low capacity decay rate of only 0.043% per cycle. In addition, in situ X-ray diffraction (XRD) and in situ Raman were used to explore the sulfur conversion process. This study not only demonstrates that a two-dimensional (2D) ultrathin Te-CoTe2/rGO composite is successfully developed with multiple effects on Li-S batteries but also opens a new pathway for designing unique sulfur hosts to promote the electrochemical performance of Li-S batteries.

Gene expression of TRPMLs and its regulation by pathogen stimulation.

The transient receptor potential mucolipin (TRPML) subfamily in mammalian has three members, namely TRPML1, TRPML2, and TRPML3, who play key roles in regulating intracellular Ca2+ homeostasis, endosomal pH, membrane trafficking and autophagy. Previous studies had shown that three TRPMLs are closely related to the occurrence of pathogen invasion and immune regulation in some immune tissues or cells, but the relationship between TRPMLs expression and pathogen invasion in lung tissue or cell remains elusive. Here, we investigated the expression distribution of three TRPML channels in mouse different tissues by qRT-PCR, and then found that all three TRPMLs were highly expressed in the mouse lung tissue, as well as mouse spleen and kidney tissues. The expression of TRPML1 or TRPML3 in all three mouse tissues had a significant down-regulation after the treatment of Salmonella or LPS, but TRPML2 expression showed a remarkable increase. Consistently, TRPML1 or TRPML3 but not TRPML2 in A549 cells also displayed a decreased expression induced by LPS stimulation, which shared a similar regulation pattern in the mouse lung tissue. Furthermore, the treatment of the TRPML1 or TRPML3 specific activator induced a dose-dependent up-regulation of inflammatory factors IL-1ß, IL-6 and TNFα, suggesting that TRPML1 and TRPML3 are likely to play an important role in immune and inflammatory regulation. Together, our study identified the gene expression of TRPMLs induced by pathogen stimulation in vivo and in vitro, which may provide novel targets for innate immunity or pathogen regulation.

Two Dual-Function Zr/Hf-MOFs as High-Performance Proton Conductors and Amines Impedance Sensors.

In the field of sensing, finding high-performance amine molecular sensors has always been a challenging topic. Here, two highly stable 3D MOFs DUT-67(Hf) and DUT-67(Zr) with large specific surface areas and hierarchical pore structures were conveniently synthesized by solvothermal reaction of ZrCl4/HfCl4 with a simple organic ligand, 2,5-thiophene dicarboxylic acid (H2TDC) according to literature approach. By analyzing TGA data, it was found that the two MOFs have defects (unsaturated metal sites) that can interact with substrates (H2O and volatile amine gas), which is conducive to proton transfer and amine compound identification. Further experiments showed that at 100 °C and 98% relative humidity (RH), the optimized proton conductivities of DUT-67(Zr) and DUT-67(Hf) can reach the high values of 2.98 × 10-3 and 3.86 × 10-3 S cm-1, respectively. Moreover, the room temperature sensing characteristics of MOFs' to amine gases were evaluated at 68, 85 and 98% RHs, respectively. Impressively, the prepared MOFs-based sensors have the desired stability and higher sensitivity to amines. Under 68% RH, the detection limits of DUT-67(Zr) or DUT-67(Hf) for volatile amine gases were 0.5 (methylamine), 0.5 (dimethylamine) and 1 ppm (trimethylamine), and 0.5 (methylamine), 0.5 (dimethylamine) and 0.5 ppm (trimethylamine), respectively. As far as we know, this is the best performance of ammonia room temperature sensors in the past proton-conductive MOF sensors.

SNHG1 functions as a ceRNA in hypertrophic scar fibroblast proliferation and apoptosis through miR-320b/CTNNB1 axis.

Hypertrophic scar (HS) is a fibrotic disease caused by skin injury. Competing endogenous RNA (ceRNA) has been demonstrated to implicate in the regulation of cell malignant phenotypes. This research aims to reveal the effect of catenin beta 1 (CTNNB1) on the functions of hypertrophic scar fibroblasts (HSFBs) and its role in a ceRNA network. RNA expression level was assessed by quantitative reverse transcription polymerase chain reaction (RT-qPCR). The proliferation and apoptosis of HSFB was detected via Cell Counting Kit-8 (CCK-8) assay and flow cytometry analysis. Mechanism experiments included RNA pull down assay, luciferase reporter assay and RNA-binding protein immunoprecipitation (RIP) assay were applied to analyze the upstream molecular mechanism of CTNNB1. CTNNB1 was highly expressed in HSFB. CTNNB1 depletion repressed malignant growth of HSFB. Mechanically, CTNNB1 was targeted by microRNA-320b (miR-320b) in HSFB. Small nucleolar RNA host gene 1 (SNHG1) aced as a ceRNA to upregulate CTNNB1 expression via sponging miR-320b in HSFB. CTNNB1 overexpression could reverse the impact of SNHG1 depletion on the proliferation and apoptosis of HSFB. SNHG1 acts as a ceRNA in modulating HSFB proliferation and apoptosis through miR-320b/CTNNB1 axis. SNHG1 act as a ceRNA to promote HSFB growth by sponging miR-320b to upregulate CTNNB1.

Rational Construction of Metal Organic Framework Hybrid Assemblies for Visible Light-Driven CO2 Conversion.

Photocatalytic reduction of CO2 to value-added chemicals is known to be a promising approach for CO2 conversion. The design and preparation of ideal photocatalysts for CO2 conversion are of pivotal significance for the sustainable development of the whole society. In this work, we integrated two functional organic linkers to prepare a novel metal organic framework (MOF) photocatalyst {[Co(9,10-bis(4-pyridyl)anthracene)0.5(bpda)]·4DMF} (Co-MOF). The existence of anthryl and amino groups leads to a wide range of visible light absorption and efficient separation of photogenerated electrons. To extend the lifetime of photogenerated electrons in the photocatalytic system, we modified Co-MOF particles onto g-C3N4. As expected, Co-MOF/g-C3N4 composites exhibited an ultrahigh selectivity (more than 97%) in the photocatalytic process, and the highest CO production rate (1824 µmol/g/h) was 7.1 and 27.2 times of Co-MOFs and g-C3N4, respectively. What's more, we also discussed the reaction mechanism of the Co-MOF/g-C3N4 photocatalytic CO2 reduction, and this work paves the pathway for designing photocatalysts with ideal CO2 reduction performance.

The role of selenium vacancies functionalized mediator of bimetal (Co, Fe) selenide for high-energy-density lithium-sulfur batteries.

Lithium-sulfur (Li-S) batteries are currently only in the basic research stage and have not been commercialized, which is mainly affected by the poor conductivity of sulfur/lithium sulfide (S/Li2S), volume expansion effect of sulfur and the shuttle effect of lithium polysulfides (LiPSs). Herein, a three dimensional (3D) carbon nanotubes (CNTs) decorated cubic Co9Se8-x/FeSe2-y (0 ï¼œ x ï¼œ 8, 0 ï¼œ y ï¼œ 2) composite (Co9Se8-x/FeSe2-y@CNTs) is developed, and used as the functionalized mediator on polypropylene (PP) in Li-S batteries. Benefiting from the good electrical conductivity, large number of Se vacancies and the triple block/adsorption/catalytic effects of Co9Se8-x/FeSe2-y@CNTs, the cell with Co9Se8-x/FeSe2-y@CNTs//PP modified separator delivers a high reversible capacity (1103.5 mA h g-1) at 1C after three cycles activation at 0.5C and remains 446 mA g h-1 after 750 cycles with a 0.08% capacity decay rate each cycle. Moreover, at 0.2C, a high areal capacity of 3.63 mA h cm-2 after 100 cycles with a high sulfur loading of 4.1 mg cm-2 is obtained. The in-situ XRD tests revealing the transition path of α-S8 â†’ Li2S â†’ ß-S8 during the first charge-discharge process, then ß-S8 â†’ Li2S â†’ ß-S8 conversion reaction in the next cycles, and firstly determine the sulfur-selenide active intermediates (Se1.1S6.9) during cycles. The work provides a new insight into the development of bimetallic selenide composites by defect engineering with highly adsorptive and catalytic properties for Li-S batteries.

High Water-Assisted Proton Conductivities of Two Cadmium(II) Complexes Constructed from Zwitterionic Ligands.

Finding more metal complexes with outstanding water stability and high proton conductivity still has important research significance for the energy field. Herein, two highly proton-conductive complexes, one hydrogen-bonded supramolecular framework (HSF) [Cd(CBIA)2(H2O)4]·2H2O (1) and one coordination polymer (CP), {[Cd2(CBIA)2(4,4'-bipy)2(H2O)2]·(CBIA)·(OH)·2H2O}n (2) (4,4'-bipy = 4,4'-bipyridine), were triumphantly assembled using a zwitterionic organic compound, 2-(1-(carboxymethyl)-1H-benzo[d]imidazol-3-ium-3-yl)acetate (HCBIA). In the structure of HSF 1, there are several coordination and lattice H2O units except for the two monodentate CBIA- anions. CP 2 with a one-dimensional (1D) cylindrical structure has free CBIA- units and free H2O units located in the cavity. Thanks to the ability of the uncoordinated carboxyl groups and coordination/lattice water molecules to construct the rich H-bonding networks, both complexes exhibit super-high proton conductivities, reaching 5.09 × 10-3 and 3.41 × 10-3 S cm-1 under 100 °C/98% relative humidity (RH), respectively. Based on the exploration of crystal structure data, combined with the calculated activation energy, and adsorption/desorption plots of nitrogen and water vapor, the causes and differences in proton conductivity of the two complexes, especially the proton-conductive mechanism, are compared and analyzed. This study again confirms that the zwitterionic ligands can exert important effects on forming organo-inorganic hybrid materials with high proton conductivity.

Long-lasting photocatalytic activity of trace phosphorus-doped g-C3N4/SMSO and its application in antibacterial ceramics.

Conventional photocatalysts generate numerous active species-primarily hydroxyl radicals (•OH)-under solar light excitation to exert photocatalytic activity for especially antibacterial effects. However, the light dependence limits their competitiveness against other antimicrobial materials since they do not work at night. Herein, a P-g-C3N4/Sr2MgSi2O7:Eu2+,Dy3+ (P-g-C3N4/SMSO) composite day-night photocatalyst is synthesized, using a model methyl orange (MO) substrate, and the impacts of trace P doping and the SMSO composite on the activity of the photocatalyst in MO degradation is investigated; Its antibacterial effect against Escherichia coli and Staphylococcus aureus on ceramic surfaces is further examined. The morphology, structure, and composition of the photocatalyst are characterized by SEM, TEM, XRD, FT-IR, and UV-vis DRS. Finally, the photocatalytic mechanism is elucidated through active species capture experiments and ESR testing. P doping and the SMSO heterojunction structure reduce the width of the forbidden band of g-C3N4 and broaden its visible-light-response range. Moreover, SMSO acts as a light source to realize long-lasting photocatalytic performance of the composite, even in the dark. The photocatalytic process produces •O2-, 1O2, and h+ active species, with •O2- and 1O2 playing the dominant role-instead of •OH as previously thought.

[Comparison of the extraction methods of plasma exosomes from human umbilical cord blood].

We compared ultracentrifugation, sucrose gradient centrifugation, improved ultracentrifugation, and polyethylene glycol (PEG) precipitation in the extraction of plasma exosomes from human umbilical cord blood, aiming at screening out a stable and efficient method. The morphology, structure, and size of exosomes were observed based on transmission electron microscopy and dynamic light scattering. Total protein content of exosomes was determined by bicinchoninic acid (BCA) assay, and the expression of exosome markers CD63 and HSP70 and exosome negative marker GM130 (Golgi marker) by Western blotting. Results showed that sucrose gradient centrifugation was more stable and yielded exosomes of uniform particle size compared with ultracentrifugation which had been considered as the "gold standard" for exosome extraction. However, sucrose gradient centrifugation had the limitations of complex operation and time-intensiveness. The improved ultracentrifugation featured ease of implementation and the extracted exosomes were of high purity. PEG precipitation extracted the most exosomes in a shorter timeframe, but the purity of the exosomes was low. In conclusion, all the four methods can separate exosomes from human umbilical cord blood plasma, but they are different in operation time, product purity, and product content. Therefore, the method for extracting plasma exosomes from human umbilical cord blood should be selected based on the experimental purpose and specific requirements.

Extraordinary electrochemical performance of lithium-sulfur battery with 2D ultrathin BiOBr/rGO sheet as an efficient sulfur host.

There are many challenges such as the shuttling effect of soluble lithium polysulfides species (LiPSs) and the slow solid-state conversion between Li2S4 and Li2S in the development process of lithium-sulfur battery (LSB), so it is vital how to design and fabricate sulfur hosts with strong adsorption and good electrocatalysis. In this work, BiOBr in-situ forms onto both sides of reduced graphene oxide (rGO) to obtain a novel ultrathin BiOBr/rGO sheet, then self-constructing a hydrogel cylinder in shape, via a one-step hydrothermal process. The BiOBr/rGO composite with sandwich structure not only shows the outstanding adsorption effect on LiPSs, resulting from a strong bonding interaction between BiOBr/rGO and Li2S6 demonstrated by XPS technique, but also exhibits the extraordinary electrocatalytic performance on both the LiPSs conversion reaction in cyclic voltammetry experiment of symmetric cell and the Li2S nucleation process in potentiostatic deposited experiment, which will significantly improve the electrochemical performance of LSB. The S@BiOBr/rGO electrodes deliver the superior capacity and long cyclic stability with 882.2 mA h g-1 at 0.5 C after 1000 cycles, as well as displays the excellent rate performance with 823.9, 692.6 and 554.2 mA h g-1 at 1 C, 3 C and 5 C, respectively, after 400 cycles. Even though the sulfur loading reaches 4.9 mg cm-1, the reversible specific capacity of 424.6 mA h g-1can be maintained at 0.5 C after 400 cycles. Based on the in-situ X-ray diffraction and in-situ Raman spectroscopy, it could be revealed that the initial discharge process of active sulfur on the BiOBr/rGO cathode is α-S8 â†’ Li2S8 â†’ Li2S6 â†’ Li2S3 â†’ Li2S2 â†’ Li2S, while the charging progress is the corresponding reverse reaction, but the final substance is ß-S8. This research not only shows that the two-dimensional ultrathin BiOBr/rGO hybrid is successfully developed in LSB with excellent electrochemical performances, but also provides a strategy for exploring the construction of sulfur host materials.