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1.
Small ; 20(11): e2306836, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37932023

ABSTRACT

The synthesis and characterization of an FeII /FeIII metal-organic framework (MOF) nanocrystal with spatial heterogeneity that arises from the non-uniform distribution of different valence states is disclosed. The FeII /FeIII -Ni Prussian blue analog (PBA) delivers superior photocatalytic performance in the selective CO2 reduction reaction thanks to the strong FeII /FeIII coupling, with CO yield up to 12.27 mmol g-1 h-1 and 90.6% selectivity under visible-light irradiation. Density functional theory calculation and experimental studies prove that the spatial heterogeneity of FeII /FeIII in the individual MOF nanocrystal not only directs and expedites the charge transfer within a catalyst particle but also creates the heterogeneity of catalytically-active Ni sites for efficient CO2 photoreduction. The current findings add to a growing literature of materials with compositional heterogeneity and provide a reference for future research.

2.
Small ; 19(16): e2206873, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36609921

ABSTRACT

Preparation of holey, single-crystal, 2D nanomaterials containing in-plane nanosized pores is very appealing for the environment and energy-related applications. Herein, an in situ topological transformation is showcased of 2D layered double hydroxides (LDHs) allows scalable synthesis of holey, single-crystal 2D transition metal oxides (TMOs) nanomesh of ultrathin thickness. As-synthesized 2D Co/NiO-2 nanomesh delivers superior photocatalytic CO2 -syngas conversion efficiency (i.e., VCO of 32460 µmol h-1 g-1 CO and V H 2 ${V_{{{\rm{H}}_2}}}$ of 17840 µmol h-1 g-1 H2 ), with VCO about 7.08 and 2.53 times that of NiO and 2D Co/NiO-1 nanomesh containing larger pore size, respectively. As revealed in high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), the high performance of Co/NiO-2 nanomesh primarily originates from the edge sites of nanopores, which carry more defect structures (e.g., atomic steps or vacancies) than basal plane for CO2 adsorption, and from its single-crystal structure adept at charge transport. Theoretical calculation shows the topological transformation from 2D hydroxide to holey 2D oxide can be achieved, probably since the trace Co dopant induces a lattice distortion and thus a sharp decrease of the dehydration energy of hydroxide precursor. The findings can advance the design of intriguing holey 2D materials with well-defined geometric and electronic properties.

3.
Chin J Integr Med ; 29(5): 424-433, 2023 May.
Article in English | MEDLINE | ID: mdl-35412217

ABSTRACT

OBJECTIVE: To investigate the effects of composite Sophora colon-soluble Capsule (CSCC) on gut microbiota-mediated short-chain fatty acids (SCFAs) production and downstream group 3 innate lymphoid cells (ILC3s) of dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mice model. METHODS: The main components of CSCC were analyzed by hybrid ultra-high-performance liquid chromatography ion mobility spectromety quadrupole time-of-flight mass spectrometry (UHPLC-IM-QTOF/MS). Twenty-four male BALB/c mice were randomly divided into 4 groups (n=6) by using a computer algorithm-generated random digital, including control, DSS model, mesalazine, and CSCC groups. A DSS-induced colitis mice model was established to determine the effects of CSCC by recording colonic weight, colonic length, index of colonic weight, and histological colonic score. The variations in ILC3s were assessed by immunofluorescence and flow cytometry. The results of gut microbiota and SCFAs were acquired by 16s rDNA and gas chromatography-mass spectrometry (GC-MS) analysis. The expression levels of NCR+ ILC3-, CCR6+ Nkp46- (Lti) ILC3-, and ILCreg-specific markers were detected by enzyme-linked immunosorbent assay, and real-time quantitative polymerase chain reaction and Western blot, respectively. RESULTS: The main components of CSCC were matrine, ammothamnine, Sophora flavescens neoalcohol J, and Sophora oxytol U. After 7 days of treatment, CSCC significantly alleviated colitis by promoting the reproduction of intestinal probiotics manifested as upregulation of the abundance of Bacteroidetes species and specifically the Bacteroidales_S24-7 genus (P<0.05). Among the SCFAs, the content of butyric acid increased the most after CSCC treatment. Meanwhile, compared with the model group, Lti ILC3s and its biomarkers were significantly downregulated and NCR+ ILC3s were significantly elevated in the CSCC group (P<0.01). Further experiments revealed that ILC3s were differentiated from Lti ILC3s to NCR+ ILC3s, resulting in interleukin-22 production which regulates gut epithelial barrier function. CONCLUSION: CSCC may exert a therapeutic effect on UC by improving the gut microbiota, promoting metabolite butyric acid production, and managing the ratio between NCR+ ILC3s and Lti ILC3s.


Subject(s)
Colitis, Ulcerative , Colitis , Gastrointestinal Microbiome , Sophora , Male , Animals , Mice , Colitis, Ulcerative/chemically induced , Colitis, Ulcerative/drug therapy , Colitis, Ulcerative/pathology , Immunity, Innate , Butyric Acid/metabolism , Butyric Acid/pharmacology , Butyric Acid/therapeutic use , Lymphocytes , Colon , Colitis/chemically induced , Colitis/metabolism , Colitis/pathology , Disease Models, Animal , Mice, Inbred C57BL
4.
ACS Appl Mater Interfaces ; 14(47): 52868-52876, 2022 Nov 30.
Article in English | MEDLINE | ID: mdl-36395169

ABSTRACT

This work disclosed the trade-off effect of two metal sites, which display distinct, key functionalities in naturally occurring and artificial catalysts for developing an advanced CO2 reduction system. To exploit the metal-organic frameworks (MOFs) as advanced catalysts, we prepared a series of Prussian blue analogues (FeNix PBAs) of tunable Ni/Fe molar ratio without changing the oxidation state of Fe and Ni for use as a photocatalyst in the CO2 reduction reaction (CRR). The FeNi0.66 PBA gives a superior CO yield rate (14.28 mmol·g-1·h-1) with nearly 100% CO selectivity, but the PBA would be basically CRR-inactive without either Ni or Fe. Experimental and calculation studies demonstrate that Fe and Ni display distinct functionalities. Specifically, Fe is an efficient mediator that boosts the electron transfer both from the photosensitizer to FeNix PBA and from FeNix PBA to CO2, and Ni serves as the active site for CO2 adsorption and reduction. Intriguingly, when there is already sufficient Ni in the catalyst, further increase of the Ni content gives marginal gains in the CO2 adsorption affinity that cannot offset the weakened electron transfer due to the Ni excess. The findings can help advance the design of bimetallic MOF catalysts that mimic naturally occurring bimetallic catalysts.

5.
Small ; 18(28): e2201668, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35833293

ABSTRACT

Exploitation of atomic-level principles to optimize the charge transfer on ultrathin 2D heterostructures is an emerging frontier in relieving the energy and environmental crisis. Herein, a facile "topological-atom-extraction" protocol is disclosed, i.e., selective extraction of Zn from ultrathin half-unit-cell ZnIn2 S4 (HZIS) can embed thin In2 O3 domain into 1.60 nm thick HZIS layer to create an atomically thin in-plane In2 O3 /HZIS heterostructure. Thanks to the optimal distance and capability of charge separation, the in-plane In2 O3 /HZIS heterostructure is among the best ZnIn2 S4 -based CO2 reduction reaction (CRR) photocatalysts, and indeed demonstrates a significant increase (from 6.8- to 128-fold) in CO production rate compared with those of out-plane ZIS@In2 O3 and out-plane In2 O3 -HZIScalcined heterostructures. Density Functional Theory simulation reveals that whereas the out-plane heterostructure has a much smaller ∆q of 0.2-0.25 e, the in-plane heterostructure with "zero distance contact" has an optimal ∆q of 1.05 e between In2 O3 and HZIS that induces remarkable charge redistribution on the in-plane heterojunction interface and creates local electric field confined within the ultrathin layer. The charge redistribution efficiently directs the charge-carrier separation in S-scheme photocatalytic system and endows long-lifetime carrier to CRR active HZIS. The findings demonstrate the strong versatility of engineering atomic-level heterojunctions for efficient catalysts design.

6.
mSystems ; 5(4)2020 Aug 04.
Article in English | MEDLINE | ID: mdl-32753503

ABSTRACT

Many Gram-negative bacteria infect hosts and cause diseases by translocating a variety of type III secreted effectors (T3SEs) into the host cell cytoplasm. However, despite a dramatic increase in the number of available whole-genome sequences, it remains challenging for accurate prediction of T3SEs. Traditional prediction models have focused on atypical sequence features buried in the N-terminal peptides of T3SEs, but unfortunately, these models have had high false-positive rates. In this research, we integrated promoter information along with characteristic protein features for signal regions, chaperone-binding domains, and effector domains for T3SE prediction. Machine learning algorithms, including deep learning, were adopted to predict the atypical features mainly buried in signal sequences of T3SEs, followed by development of a voting-based ensemble model integrating the individual prediction results. We assembled this into a unified T3SE prediction pipeline, T3SEpp, which integrated the results of individual modules, resulting in high accuracy (i.e., ∼0.94) and >1-fold reduction in the false-positive rate compared to that of state-of-the-art software tools. The T3SEpp pipeline and sequence features observed here will facilitate the accurate identification of new T3SEs, with numerous benefits for future studies on host-pathogen interactions.IMPORTANCE Type III secreted effector (T3SE) prediction remains a big computational challenge. In practical applications, current software tools often suffer problems of high false-positive rates. One of the causal factors could be the relatively unitary type of biological features used for the design and training of the models. In this research, we made a comprehensive survey on the sequence-based features of T3SEs, including signal sequences, chaperone-binding domains, effector domains, and transcription factor binding promoter sites, and assembled a unified prediction pipeline integrating multi-aspect biological features within homology-based and multiple machine learning models. To our knowledge, we have compiled the most comprehensive biological sequence feature analysis for T3SEs in this research. The T3SEpp pipeline integrating the variety of features and assembling different models showed high accuracy, which should facilitate more accurate identification of T3SEs in new and existing bacterial whole-genome sequences.

7.
Article in English | MEDLINE | ID: mdl-29805466

ABSTRACT

Fluid resuscitation could hardly be performed immediately after fatal hemorrhagic shock in outpatients. We investigated whether electroacupuncture (EA) at Zusanli (ST36) could prevent fatal hemorrhagic shock induced heart failure with delayed fluid resuscitation and whether the protective role of EA is related to the autonomic nervous system. Sixty Sprague Dawley rats were randomly divided into five groups (n = 12 each): group of sham hemorrhagic shock (SHAM), group of EA, group of sham EA (SEA), group of delayed fluid resuscitation with EA (EA + DR), and group of delayed fluid resuscitation with SEA (SEA + DR). After blood loss for 6 hours, caspase-3 activity and positive rate of TUNEL in EA + DR group were significantly lower than in other hemorrhagic shock groups (e.g., versus SEA + DR: 0.156 ± 0.039 versus 0.301 ± 0.042; P < 0.05). Immediately EA treatment after the blood loss enhanced the protective effect of delayed resuscitation on the cardiac tissue of hemorrhagic shock rats. Considering the significant changes of epinephrine (137.8 ± 6.9 ng/L versus 98.6 ± 7.4 ng/L; P < 0.05) and acetylcholine (405 ± 8.6 pmol/L versus 341 ± 10.1 pmol/L; P < 0.05) after EA treatment (SEA + DR versus EA + DR), this cardiac protective effect may be related to regulation of the autonomic nervous system.

8.
Chin J Integr Med ; 18(9): 663-9, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22936319

ABSTRACT

OBJECTIVE: To investigate the effects of brachytherapy with computed tomography-guided percutaneous radioactive I-125 seeds interstitial implantation (ISI) synchronized chemotherapy and Chinese medicine (CM) for the treatment of advanced stage of non-small cell lung cancer (NSCLC). METHODS: Ninety patients diagnosed with NSCLC by biopsy were randomly assigned to three groups: the synchronized therapy group (A), the chemotherapy plus CM-treated group (B), and the chemotherapy-treated group (C); a 2-month course of treatment was administered to them all. The effectiveness of treatment was evaluated based on tumor size, tumor markers (carcinoembryonic, squamous cell carcinoma-associated antigen, and cytokeratin 19 fragment), clinical symptoms, and quality of life (QOL) in patients. RESULTS: The total effective rates of Groups A to C were 83.33%, 46.67%, and 43.33%, respectively. The tumor markers were reduced obviously in Group A, showing signifificant difference compared with those in the other two groups. Additionally, QOL was elevated and cancer-related symptoms were alleviated more signifificant in Group A than those in Group C (all P<0.05). CONCLUSION: The synchronized therapy of I-125 implantation with chemotherapy and CM was a safe therapeutic method and can be regarded as a new mode for treatment of advanced-stage NSCLC.


Subject(s)
Brachytherapy , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/radiotherapy , Drugs, Chinese Herbal/therapeutic use , Lung Neoplasms/drug therapy , Lung Neoplasms/radiotherapy , Antineoplastic Agents/adverse effects , Antineoplastic Agents/therapeutic use , Biomarkers, Tumor/metabolism , Brachytherapy/adverse effects , Combined Modality Therapy , Female , Humans , Iodine Radioisotopes , Male , Middle Aged , Quality of Life , Treatment Outcome
9.
Nan Fang Yi Ke Da Xue Xue Bao ; 31(2): 266-8, 2011 Feb.
Article in Chinese | MEDLINE | ID: mdl-21354908

ABSTRACT

OBJECTIVE: To observe the effect of Liangxuehuoxue Recipe (LXHXF), a compound traditional Chinese medicinal preparation, on the expressions of tumor necrosis factor-α (TNF-α) and transforming growth factor-ß (TGF-ß) in the lung tissue of rats exposed to X-ray radiation. METHODS: Seventy-two Wistar rats were randomized into exposure group (group A, without treatment) and small-, middle- and high-dose LXHXF groups (groups B, C, and D treated with LXHXF at the daily doses of 9, 18, and 36 g/kg, respectively). After X-ray exposure of the right lung at 3 Gy twice a week for 5 consecutive weeks, the rats were sacrificed at the end of the 5th, 12th and 26th weeks, and the lung tissues were taken for immunohistochemistry of the expressions of TNF-α and TGF-ß. RESULTS: In group A, the expression of TNF-α reached the peak level at 5 weeks and TGF-ß expression was the highest at 12 and 26 weeks. LXHXF, especially at the middle and high doses, obviously inhibited the expression of TNF-α at 5 weeks; the treatments also resulted in significantly lowered expressions of TGF-ß at all the time points of observation as compared with those in group A (P<0.01). The high- and middle-dose groups exhibited no significant difference in the expression levels of TNF-α and TGF-ß in the experiment (P>0.05). CONCLUSION: Treatment with LXHXF can effectively inhibit TNF-α expression in the lung tissue in the early stage following radiation exposure, causing even more obvious inhibitory effect on TGF-ß in the later stages. A higher dose of LXHXF produces more significant inhibitory effects on TNF-α and TGF-ß expressions.


Subject(s)
Drugs, Chinese Herbal/pharmacology , Lung/radiation effects , Radiation Injuries/prevention & control , Transforming Growth Factor beta/metabolism , Tumor Necrosis Factor-alpha/metabolism , Animals , Lung/metabolism , Male , Radiation Injuries/metabolism , Radiation-Protective Agents/pharmacology , Random Allocation , Rats , Rats, Wistar , Transforming Growth Factor beta/genetics , Tumor Necrosis Factor-alpha/genetics
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