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1.
Langmuir ; 40(22): 11526-11533, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38767843

ABSTRACT

This study investigates the optimization of hematite (α-Fe2O3) photoanodes for enhanced photoelectrochemical (PEC) performance and reproducibility, which are crucial for photocatalytic applications. Despite hematite's potential, hindered by inherent limitations, significant improvements were realized by introducing a titanium dioxide (TiO2) underlayer and ethanol-modified deposition. The influence of the deposition methods was understood by potential-dependent photoelectrochemical impedance spectroscopy analysis. The introduction of the TiO2 underlayer effectively increased the density of states, preferable for the electron transport in the bulk hematite, and the ethanol deposition on a TiO2 underlayer led to a stable surface state formation (S1 state) for the photoexcited hole transfer. This analysis illuminated the intricate interplay between electron transport in the bulk and photogenerated hole transfer at the solution interface, thereby facilitating smoother charge transfer. These findings underscore the viability of surface engineering and meticulous process optimization in addressing critical challenges in photocatalyst development.

2.
Analyst ; 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38984992

ABSTRACT

Machine learning (ML) is increasingly applied across various fields, including chemistry, for molecular design and optimizing reaction parameters. Yet, applying ML to experimental data is challenging due to the limited number of synthesized samples, which restricts its broader application in device development. In energy harvesting, photoanodes are crucial for solar-driven water splitting, generating hydrogen and oxygen. We explored electrodes like hematite and bismuth vanadate for photocatalytic uses, noting varied photoelectrochemical performances despite similar preparations. To understand this variability, we applied a data-driven ML approach, predicting photocurrent values and identifying key performance influencers even with limited experimental data in the research development of inorganic devices. We have utilized multiple machine learning algorithms to predict the target value in the calculation process, where the contributions of the dominant descriptors were unknown. We introduced a novel methodology, incorporating clustering to manage multicollinearity from correlated analytical data and Shapley analysis for clear interpretation of contributions to performance prediction. This method was validated on hematite and bismuth vanadate, showing superior predictability and factor identification, and then extended to tungsten oxide and bismuth vanadate heterojunction photoanodes. Despite their complexity, our approach achieved determination coefficients (R2) with a prediction accuracy over 0.85, successfully pinpointing performance-determining factors, demonstrating the robustness of the new scheme in advancing photodevice research.

3.
J Chem Phys ; 160(16)2024 Apr 28.
Article in English | MEDLINE | ID: mdl-38647310

ABSTRACT

Photocatalytic water-splitting represents a promising avenue for clean hydrogen production, necessitating an in-depth understanding of the photocatalytic reaction mechanism. The majority of the photocatalytic materials need cocatalysts to enhance the photo-oxidation or reduction reactions. However, the working mechanism, such as collecting charge carriers or reducing the reaction barrier, is not clear because they disperse inhomogeneously on a surface, and it is difficult to follow the local charge carrier behavior. This study employs the pattern-illumination time-resolved phase microscopy (PI-PM) method to unravel the spatial charge carrier behavior in photocatalytic systems, utilizing time-resolved microscopic image (refractive index change) sequences and their clustering analyses. This approach is robust for studying the change in local charge carrier behavior. We studied two major cocatalyst effects on photocatalysts: TiO2 with/without Pt and hematite with/without CoPi. The PI-PM method, supported by charge type clustering and the effects of scavengers, allowed for the analysis of local activity influenced by cocatalysts. This approach revealed that the introduction of cocatalysts alters the local distribution of charge carrier behavior and significantly impacts their decay rates. In TiO2 systems, the presence of Pt cocatalysts led to a local electron site on the micron scale, extending the lifetime to a few tens of microseconds from a few microseconds. Similarly, in hematite films with CoPi, we observed a notable accumulation of holes at cocatalyst sites, emphasizing the role of cocatalysts in enhancing photocatalytic efficiency. The study's findings highlight the complexity of charge carrier dynamics in photocatalytic processes and the significant influence of cocatalysts.

4.
Proc Natl Acad Sci U S A ; 117(12): 6376-6382, 2020 03 24.
Article in English | MEDLINE | ID: mdl-32161133

ABSTRACT

Redox cocatalysts play crucial roles in photosynthetic reactions, yet simultaneous loading of oxidative and reductive cocatalysts often leads to enhanced charge recombination that is detrimental to photosynthesis. This study introduces an approach to simultaneously load two redox cocatalysts, atomically dispersed cobalt for improving oxidation activity and anthraquinone for improving reduction selectivity, onto graphitic carbon nitride (C3N4) nanosheets for photocatalytic H2O2 production. Spatial separation of oxidative and reductive cocatalysts was achieved on a two-dimensional (2D) photocatalyst, by coordinating cobalt single atom above the void center of C3N4 and anchoring anthraquinone at the edges of C3N4 nanosheets. Such spatial separation, experimentally confirmed and computationally simulated, was found to be critical for enhancing surface charge separation and achieving efficient H2O2 production. This center/edge strategy for spatial separation of cocatalysts may be applied on other 2D photocatalysts that are increasingly studied in photosynthetic reactions.

5.
Angew Chem Int Ed Engl ; 62(46): e202312938, 2023 Nov 13.
Article in English | MEDLINE | ID: mdl-37786233

ABSTRACT

Photocatalytic water splitting is a simple means of converting solar energy into storable hydrogen energy. Narrow-band gap oxysulfide photocatalysts have attracted much attention in this regard owing to the significant visible-light absorption and relatively high stability of these compounds. However, existing materials suffer from low efficiencies due to difficulties in synthesizing these oxysulfides with suitable degrees of crystallinity and particle sizes, and in constructing effective reaction sites. The present work demonstrates the production of a Gd2 Ti2 O5 S2 (λ<650 nm) photocatalyst capable of efficiently driving photocatalytic reactions. Single-crystalline, plate-like Gd2 Ti2 O5 S2 particles with atomically ordered surfaces were synthesized by flux and chemical etching methods. Ultrafine Pt-IrO2 cocatalyst particles that promoted hydrogen (H2 ) and oxygen (O2 ) evolution reactions were subsequently loaded on the Gd2 Ti2 O5 S2 while ensuring an intimate contact by employing a microwave-heating technique. The optimized Gd2 Ti2 O5 S2 was found to evolve H2 from an aqueous methanol solution with a remarkable apparent quantum efficiency of 30 % at 420 nm. This material was also stable during O2 evolution in the presence of a sacrificial reagent. The results presented herein demonstrates a highly efficient narrow-band gap oxysulfide photocatalyst with potential applications in practical solar hydrogen production.

6.
Phys Chem Chem Phys ; 24(29): 17485-17495, 2022 Jul 27.
Article in English | MEDLINE | ID: mdl-35822609

ABSTRACT

Visible-light responsive photocatalytic materials are expected to be deployed for practical use in photocatalytic water splitting. One of the promising materials as a p-type semiconductor, oxysulfides, was investigated in terms of the local charge carrier behavior for each particle by using a home-built time-resolved microscopic technique in combination with clustering analysis. We could differentiate electron and hole trapping to the surface states and the following recombination on a micron-scale from the nanosecond to microsecond order. The map of the charge carrier type revealed that charge trapping sites for electrons and holes were spatially separated within each particle/aggregate. Furthermore, the effect of the rhodium cocatalyst was recognized as a new electron pathway, trapping to the rhodium site and the following recombination, which was delayed compared with the original electron recombination process. The Rh effect was discussed based on the phenomenological simulation, revealing a possible reason for the decay was due to the anisotropic diffusion of charge carriers in oxysulfides or the interfacial energy barrier at the interface.

7.
Int J Mol Sci ; 24(1)2022 Dec 28.
Article in English | MEDLINE | ID: mdl-36613925

ABSTRACT

Lung adenocarcinoma (LUAD) is a major subtype of lung cancer, and its prognosis is still poor due to therapy resistance, metastasis, and recurrence. In recent years, increasing evidence has shown that the existence of lung cancer stem cells is responsible for the propagation, metastasis, therapy resistance, and recurrence of the tumor. During their transition to cancer stem cells, tumor cells need to inhibit cell differentiation and acquire invasive characteristics. However, our understanding of the property and role of such lung cancer stem cells is still limited. In this study, lung adenocarcinoma cancer stem cells (LCSCs) were enriched from the PC-9 cell line in a serum-free condition. PC-9 cells grew into spheres and showed higher survival rates when exposed to gefitinib: the drug used for the treatment of LUAD. Additionally, we found that the canonical stemness marker protein CD44 was significantly increased in the enriched LCSCs. Then, LCSCs were inoculated into the groin of nude mice for 1.5 months, and tumors were detected in the animals, indicating the strong stemness of the cells. After that, we performed single-cell RNA sequencing (scRNA-seq) on 7320 LCSCs and explored the changes in their transcriptomic signatures. We identified cell populations with a heterogeneous expression of cancer stem marker genes in LCSCs and subsets with different degrees of differentiation. Further analyses revealed that the activation of the FOXM1 (oncoprotein) transcription factor is a key factor in cell dedifferentiation, which enables tumor cells to acquire an epithelial-mesenchymal transition phenotype and increases the LCSC surface marker CD44. Moreover, we found that the combination of CD44, ABCG2, and ALCAM was a specific marker for LCSCs. In summary, this study identified the potential factors and molecular mechanisms underlying the stemness properties of LUAD cancer cells; it could also provide insight into developing novel and effective therapeutic approaches.


Subject(s)
Adenocarcinoma of Lung , Lung Neoplasms , Animals , Mice , Transcriptome , Mice, Nude , Adenocarcinoma of Lung/pathology , Lung Neoplasms/pathology , Neoplastic Stem Cells/metabolism , Cell Line, Tumor
8.
J Am Chem Soc ; 143(28): 10633-10641, 2021 07 21.
Article in English | MEDLINE | ID: mdl-34235922

ABSTRACT

Charge separation is crucial for an efficient artificial photosynthetic process, especially for narrow-bandgap metal sulfides/selenides. The present study demonstrates the application of a p-n junction to particulate metal selenides to enhance photocatalytic Z-scheme overall water splitting (OWS). The constructed p-n junction of CdS-(ZnSe)0.5(CuGa2.5Se4.25)0.5 significantly boosted charge separation. A thin TiO2 coating layer also was introduced to inhibit photocorrosion of CdS and suppress the backward reaction of water formation from hydrogen and oxygen. By employing Pt-loaded TiO2/CdS-(ZnSe)0.5(CuGa2.5Se4.25)0.5 as a hydrogen evolution photocatalyst (HEP), we assembled a Z-scheme OWS system, together with BiVO4:Mo and Au as an oxygen evolution photocatalyst and electron mediator, respectively. An apparent quantum yield of 1.5% at 420 nm was achieved, which is by far the highest among reported particulate photocatalytic Z-scheme OWS systems with metal sulfides/selenides as HEPs. The present work demonstrates that a well-tailored p-n junction structure is effective for promoting charge separation in photocatalysis and opens new pathways for the development of efficient artificial photosynthesis systems involving narrow bandgap photocatalysts.

9.
J Am Chem Soc ; 143(27): 10059-10064, 2021 Jul 14.
Article in English | MEDLINE | ID: mdl-34196527

ABSTRACT

The simultaneous control of the defect species and surface properties of semiconducting materials is a crucial aspect of improving photocatalytic performance, yet it remains challenging. Here, we synthesized Mg-Zr-codoped single-crystalline Ta3N5 (Ta3N5:Mg+Zr) nanoparticles by a brief NH3 nitridation process, exhibiting photocatalytic water reduction activity 45 times greater than that of pristine Ta3N5 under visible light. A coherent picture of the relations between the defect species (comprising reduced Ta, nitrogen vacancies and oxygen impurities), surface properties (associated with dispersion of the Pt cocatalyst), charge carrier dynamics, and photocatalytic activities was drawn. The tuning of defects and simultaneous optimization of surface properties resulting from the codoping evidently resulted in the generation of high concentrations of long-lived electrons in this material as well as the efficient migration of these electrons to evenly distributed surface Pt sites. These effects greatly enhanced the photocatalytic activity. This work highlights the importance and feasibility of improving multiple properties of a catalytic material via a one-step strategy.

10.
BMC Cancer ; 21(1): 1218, 2021 Nov 13.
Article in English | MEDLINE | ID: mdl-34774019

ABSTRACT

BACKGROUND: MicroRNAs (miRNAs) have been reported to play significant roles in non-small-cell lung cancer (NSCLC). However, the roles of microRNA (miR)-1915-3p in NSCLC remain unclear. In this study, we aimed to explore the biological functions of miR-1915-3p in NSCLC. METHODS: The expression of miR-1915-3p and SET nuclear proto-oncogene (SET) in NSCLC tissues were examined by quantitative real-time PCR (qRT-PCR). Migratory and invasive abilities of lung cancer were tested by wound healing and transwell invasion assay. The direct target genes of miR-1915-3p were measured by dual-luciferase reporter assay and western blot. Finally, the regulation between METTL3/YTHDF2/KLF4 axis and miR-1915-3p were evaluated by qRT-PCR, promoter reporter assay and chromatin immunoprecipitation (CHIP). RESULTS: miR-1915-3p was downregulated in NSCLC tissues and cell lines, and inversely associated with clinical TNM stage and overall survival. Functional assays showed that miR-1915-3p significantly suppressed migration, invasion and epithelial-mesenchymal transition (EMT) in NSCLC cells. Furthermore, miR-1915-3p directly bound to the 3'untranslated region (3'UTR) of SET and modulated the expression of SET. SET inhibition could recapitulate the inhibitory effects on cell migration, invasion and EMT of miR-1915-3p, and restoration of SET expression could abrogate these effects induced by miR-1915-3p through JNK/Jun and NF-κB signaling pathways. What's more, miR-1915-3p expression was regulated by METTL3/YTHDF2 m6A axis through transcription factor KLF4. CONCLUSIONS: These findings demonstrate that miR-1915-3p function as a tumor suppressor by targeting SET and may have an anti-metastatic therapeutic potential for lung cancer treatment.


Subject(s)
Carcinoma, Non-Small-Cell Lung/genetics , DNA-Binding Proteins/genetics , Gene Expression , Histone Chaperones/genetics , Lung Neoplasms/genetics , MicroRNAs/physiology , A549 Cells , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/mortality , Carcinoma, Non-Small-Cell Lung/pathology , Cell Movement/genetics , DNA-Binding Proteins/antagonists & inhibitors , DNA-Binding Proteins/metabolism , Down-Regulation , Epithelial-Mesenchymal Transition/genetics , Female , Genes, Reporter , Genes, Tumor Suppressor/physiology , Histone Chaperones/antagonists & inhibitors , Histone Chaperones/metabolism , Humans , Kruppel-Like Factor 4/genetics , Kruppel-Like Factor 4/metabolism , Lung Neoplasms/metabolism , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Male , Methyltransferases/genetics , Methyltransferases/metabolism , MicroRNAs/genetics , Middle Aged , Neoplasm Invasiveness/genetics , Neoplasm Proteins/genetics , Neoplasm Proteins/metabolism , RNA-Binding Proteins/genetics , RNA-Binding Proteins/metabolism
11.
Angew Chem Int Ed Engl ; 60(19): 10469-10480, 2021 May 03.
Article in English | MEDLINE | ID: mdl-32926513

ABSTRACT

Hydrogen peroxide (H2 O2 ), as a green fuel and oxidant, has drawn increasing attention in the energy and environmental research. Compared with the traditional anthraquinone process, the electrochemical (EC) and photoelectrochemical (PEC) syntheses of H2 O2 are cost-effective and environmentally friendly. In order to construct membraneless EC/PEC devices for the full H2 O2 synthesis, anodic H2 O2 production by water oxidation, which is less developed than cathodic H2 O2 generation, is highly desirable. Here, we review recent developments for the EC/PEC H2 O2 production by water oxidation, including fundamental aspects, benchmarking activity evaluation, material/catalyst selection, and strategies for increasing selectivity, efficiency, and accumulation. Furthermore, we discuss the challenges and outlook of water oxidation for H2 O2 production, especially device-level development, accumulation and stability, and industrial applications. Our review is intended to stimulate studies further improving EC/PEC H2 O2 production.

12.
Nat Mater ; 18(8): 827-832, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31209390

ABSTRACT

Oxysulfide semiconductors have narrow bandgaps suitable for water splitting under visible-light irradiation, because the electronegative sulfide ions negatively shift the valence band edges of the corresponding oxides1,2. However, the instability of sulfide ions during the water oxidation is a critical obstacle to simultaneous evolution of hydrogen and oxygen3. Here, we demonstrate the activation and stabilization of Y2Ti2O5S2, with a bandgap of 1.9 eV, as a photocatalyst for overall water splitting. On loading of IrO2 and Rh/Cr2O3 as oxygen and hydrogen evolution co-catalysts, respectively, and fine-tuning of the reaction conditions, simultaneous production of stoichiometric amounts of hydrogen and oxygen was achieved on Y2Ti2O5S2 during a 20 h reaction. The discovery of the overall water splitting capabilities of Y2Ti2O5S2 extends the range of promising materials for solar hydrogen production.

13.
J Am Chem Soc ; 139(4): 1675-1683, 2017 02 01.
Article in English | MEDLINE | ID: mdl-28059504

ABSTRACT

Development of sunlight-driven water splitting systems with high efficiency, scalability, and cost-competitiveness is a central issue for mass production of solar hydrogen as a renewable and storable energy carrier. Photocatalyst sheets comprising a particulate hydrogen evolution photocatalyst (HEP) and an oxygen evolution photocatalyst (OEP) embedded in a conductive thin film can realize efficient and scalable solar hydrogen production using Z-scheme water splitting. However, the use of expensive precious metal thin films that also promote reverse reactions is a major obstacle to developing a cost-effective process at ambient pressure. In this study, we present a standalone particulate photocatalyst sheet based on an earth-abundant, relatively inert, and conductive carbon film for efficient Z-scheme water splitting at ambient pressure. A SrTiO3:La,Rh/C/BiVO4:Mo sheet is shown to achieve unassisted pure-water (pH 6.8) splitting with a solar-to-hydrogen energy conversion efficiency (STH) of 1.2% at 331 K and 10 kPa, while retaining 80% of this efficiency at 91 kPa. The STH value of 1.0% is the highest among Z-scheme pure water splitting operating at ambient pressure. The working mechanism of the photocatalyst sheet is discussed on the basis of band diagram simulation. In addition, the photocatalyst sheet split pure water more efficiently than conventional powder suspension systems and photoelectrochemical parallel cells because H+ and OH- concentration overpotentials and an IR drop between the HEP and OEP were effectively suppressed. The proposed carbon-based photocatalyst sheet, which can be used at ambient pressure, is an important alternative to (photo)electrochemical systems for practical solar hydrogen production.

14.
Nat Mater ; 15(6): 611-5, 2016 06.
Article in English | MEDLINE | ID: mdl-26950596

ABSTRACT

Photocatalytic water splitting using particulate semiconductors is a potentially scalable and economically feasible technology for converting solar energy into hydrogen. Z-scheme systems based on two-step photoexcitation of a hydrogen evolution photocatalyst (HEP) and an oxygen evolution photocatalyst (OEP) are suited to harvesting of sunlight because semiconductors with either water reduction or oxidation activity can be applied to the water splitting reaction. However, it is challenging to achieve efficient transfer of electrons between HEP and OEP particles. Here, we present photocatalyst sheets based on La- and Rh-codoped SrTiO3 (SrTiO3:La, Rh; ref. ) and Mo-doped BiVO4 (BiVO4:Mo) powders embedded into a gold (Au) layer. Enhancement of the electron relay by annealing and suppression of undesirable reactions through surface modification allow pure water (pH 6.8) splitting with a solar-to-hydrogen energy conversion efficiency of 1.1% and an apparent quantum yield of over 30% at 419 nm. The photocatalyst sheet design enables efficient and scalable water splitting using particulate semiconductors.

15.
Acta Pharmacol Sin ; 38(4): 539-550, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28112178

ABSTRACT

Isothiocyanates, such as allyl isothiocya¬nate (AITC), benzyl isothiocyanate (BITC), phenethyl isothio¬cyanate (PEITC) and sulforaphane (SFN), are natural compounds abundant in cruciferous vegetables, which have substantial chemopreventive activities against various human malignancies. However, the mechanisms underlying the inhibition of tumor cell growth by isothiocyanates are not fully understood. Since autophagy has dual functions in cancer, in the present study we investigated the effects of BITC on autophagy induction in human lung cancer cells in vitro and in vivo. BITC (1-100 µmol/L) dose-dependently inhibited the growth of 3 different human lung cancer cell lines A549 (adenocarcinoma), H661 (large cell carcinoma) and SK-MES-1 (squamous cell carcinoma) with IC50 values of 30.7±0.14, 15.9±0.22 and 23.4±0.11 µmol/L, respectively. BITC (10-40 µmol/L) induced autophagy in the lung cancer cells, evidenced by the formation of acidic vesicular organelles (AVOs), the accumulation of LC3-II, the punctate pattern of LC3, and the expression of Atg5. Pretreatment with the autophagy inhibitor 3-MA (5 mmol/L) significantly enhanced the BITC-caused growth inhibition in the lung cancer cells. Furthermore, BITC (20-40 µmol/L) activated ER stress, as shown by the increased cytosolic Ca2+ level and the phosphorylation of the ER stress marker proteins PERK and eIF2α in the lung cancer cells. Pretreatment with the ER stress inhibitor 4-PBA (5 mmol/L) attenuated the autophagy induction and potentiated the BITC-induced cell growth inhibition. In nude mice bearing A549 xenografts, administration of BITC (100 mg·kg-1·d-1, ip) for 8 weeks markedly suppressed the lung tumor growth, and significantly enhanced both autophagy and ER stress in the tumor tissues. Our results demonstrate that BITC inhibits human lung cancer cell growth in vitro and in vivo. In addition, BITC induces autophagy in the lung cancer cells, which protects the cancer cells against the inhibitory action of BITC; the autophagy induction is mediated by the ER stress response.


Subject(s)
Autophagy/drug effects , Endoplasmic Reticulum Stress/drug effects , Isothiocyanates/therapeutic use , Lung Neoplasms/drug therapy , Adenine/analogs & derivatives , Adenine/pharmacology , Animals , Autophagy-Related Protein 5/metabolism , Cell Line, Tumor , Female , Heterografts , Humans , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Mice, Inbred BALB C , Microtubule-Associated Proteins/metabolism , Neoplasm Transplantation , Phenylbutyrates/pharmacology
16.
PLoS Genet ; 9(7): e1003613, 2013.
Article in English | MEDLINE | ID: mdl-23874216

ABSTRACT

The human gene encoding the cleavage/polyadenylation (C/P) factor CstF-77 contains 21 exons. However, intron 3 (In3) accounts for nearly half of the gene region, and contains a C/P site (pA) with medium strength, leading to short mRNA isoforms with no apparent protein products. This intron contains a weak 5' splice site (5'SS), opposite to the general trend for large introns in the human genome. Importantly, the intron size and strengths of 5'SS and pA are all highly conserved across vertebrates, and perturbation of these parameters drastically alters intronic C/P. We found that the usage of In3 pA is responsive to the expression level of CstF-77 as well as several other C/P factors, indicating it attenuates the expression of CstF-77 via a negative feedback mechanism. Significantly, intronic C/P of CstF-77 pre-mRNA correlates with global 3'UTR length across cells and tissues. In addition, inhibition of U1 snRNP also leads to regulation of the usage of In3 pA, suggesting that the C/P activity in the cell can be cross-regulated by splicing, leading to coordination between these two processes. Importantly, perturbation of CstF-77 expression leads to widespread alternative cleavage and polyadenylation (APA) and disturbance of cell proliferation and differentiation. Thus, the conserved intronic pA of the CstF-77 gene may function as a sensor for cellular C/P and splicing activities, controlling the homeostasis of CstF-77 and C/P activity and impacting cell proliferation and differentiation.


Subject(s)
Cell Differentiation/genetics , Cleavage Stimulation Factor/genetics , Introns/genetics , Polyadenylation/genetics , Ribonucleoprotein, U1 Small Nuclear/genetics , 3' Untranslated Regions/genetics , Cell Proliferation , Cleavage Stimulation Factor/metabolism , Exons/genetics , Genome, Human , HeLa Cells , Humans , RNA Splice Sites/genetics , RNA, Messenger/genetics , Ribonucleoprotein, U1 Small Nuclear/antagonists & inhibitors
17.
Zhonghua Yi Xue Za Zhi ; 95(25): 2022-6, 2015 Jul 07.
Article in Zh | MEDLINE | ID: mdl-26710815

ABSTRACT

OBJECTIVE: To investigate the effects of hydrogen-rich saline on cardiomyocyte autophagy during myocardial ischemia-reperfusion in aged rats. METHODS: One hundred and fifty healthy male Sprague Dawley rats, 18 months old, weighing 400-540 g were selected. The rats were then randomly divided into 5 groups (n = 30): Normal control group (group I); Sham operation group (group II); Myocardial ischemia-reperfusion group (group III); Hydrogen-rich saline group (group IV); Normal saline group (group V). No any processing in group I. In group II, the anterior descending branch was only exposed but not ligated. Myocardial I/R was induced by occlusion of anterior descending branch of left coronary artery for 30 min followed by 12 h and 24 h of reperfusion with Bimbaum. Hydrogen-rich saline 1 ml/100 g were injected intraperitoneally 5 min before reperfusion in group IV. Normal saline 1 ml/100 g were injected intraperitoneally 5 min before reperfusion in group V. The rats were sacrificed at 12 h and 24 h of reperfusion and hearts were removed. The pathological changes of myocardial tissue were detected by HE staining. The rate of cardiomyocyte autophagy were detected by the MDC fluorescent dye and flow cytometry instrument. The expression of AMPK, mTOR, Beclin1, LC3 in myocardial tissue was investigated by Western blot. RESULT: Compared with groups I and II, the rate of cardiomyocyte autophagy, the expression of AMPK, mTOR, Beclin1, LC3 in myocardial tissue were significantly increased at 12 h, 24 h in groups III, IV and V (F = 23.45, 26.65, 25.58; F = 23.16, 25.15, 27.85; F = 21.04, 24.83, 27.43; F = 22.15, 25.79, 29.05; F = 22.58, 27.25, 28.46), P < 0.05. Compared with group III and V, the rate of cardiomyocyte autophagy, the expression of AMPK, mTOR, Beclin1, LC3 were significantly decreased at 12 h, 24 h in group IV (F = 21.29, 24.71; F = 22.37, 25.84; F = 20.48, 22.38; F = 21.76, 28.43; F = 22.54, 27.21), P < 0.05. CONCLUSION: Hydrogen-rich saline can attenuate myocardial reperfusion injury through inhibiting cardiomyocyte autophagy. The mechanism may be associated with decreasing the expression of AMPK, mTOR, Beclin1, LC3 in myocardial tissue.


Subject(s)
Autophagy , Myocardial Reperfusion Injury , Myocytes, Cardiac , Aging , Animals , Disease Models, Animal , Hydrogen , Ischemia , Male , Myocardium , Rats , Rats, Sprague-Dawley , Sodium Chloride
18.
Expert Rev Pharmacoecon Outcomes Res ; 24(2): 285-292, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37855081

ABSTRACT

BACKGROUND: The aim of the current analysis was to evaluate the cost-effectiveness of toripalimab plus chemotherapy compared with chemotherapy alone as the first-line option for patients with advanced esophageal squamous cell carcinoma (ESCC) from the perspective of Chinese health-care system. METHODS: A partitioned survival model was conducted to track 3-week patients' transition and evaluate the health and economic outcomes in 10-year horizon of the two competing first-line treatment among toripalimab plus chemotherapy and chemotherapy alone. The survival data were gathered from the JUPITER-06 trial, and cost and utility values were obtained from the local charges and published studies. Total costs, life-years, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratio (ICER) were the model outcomes. Sensitivity and subgroup analyses were conducted. RESULTS: Treatment with toripalimab plus chemotherapy yields marginal cost of $8,639.74 and additional 0.65 QALYs, resulting in an ICER of $13,280.97 per additional QALY gained, which was lower than the willingness-to-pay (WTP) threshold of $38,224 in China. Sensitivity and subgroup analyses confirmed the robustness of the model outcomes. CONCLUSIONS: Toripalimab plus chemotherapy was likely to be the cost-effective first-line option for patients with advanced ESCC compared with chemotherapy alone with the WTP threshold of $38,224 per additional QALY gained from the perspective of the Chinese health-care system.


Subject(s)
Antibodies, Monoclonal, Humanized , Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Humans , Esophageal Squamous Cell Carcinoma/drug therapy , Cost-Effectiveness Analysis , Esophageal Neoplasms/drug therapy , Cost-Benefit Analysis , Antineoplastic Combined Chemotherapy Protocols
19.
ACS Appl Mater Interfaces ; 16(26): 33611-33619, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38899937

ABSTRACT

In the quest for sustainable energy solutions, the optimization of the photoelectrochemical (PEC) performance of hematite photoanodes through cocatalysts represents a promising avenue. This study introduces a novel machine learning approach, leveraging subtraction descriptors, to isolate and quantify the specific effects of cobalt phosphate (Co-Pi) as a cocatalyst on hematite's PEC performance. By integrating data from various analytical techniques, including photoelectrochemical impedance spectroscopy and ultraviolet-visible spectroscopy, with advanced machine learning models, we successfully predicted the PEC performance enhancement attributed to Co-Pi. The Gaussian process regression (GPR) model emerged as the most effective, revealing the critical influence of the interfacial resistance, bulk resistance, and interfacial capacitance on the PEC performance. These findings underscore the potential of cocatalysts in improving charge separation and extending charge carrier lifetimes, thereby boosting the efficiency of photocatalytic reactions. This study not only advances our understanding of the cocatalyst effect in photocatalytic systems but also demonstrates the power of machine learning in modifying complex materials and guiding the development of optimized photocatalytic materials. The implications of this research extend beyond hematite photoanodes, offering a generalizable framework for enhancing the photoelectrochemical properties of a wide range of material modifications such as cocatalyst deposition, doping, and passivation.

20.
Orthop Surg ; 16(5): 1230-1238, 2024 May.
Article in English | MEDLINE | ID: mdl-38556478

ABSTRACT

OBJECTIVES: Unstable trimalleolar fractures are relatively complex and more difficult to manage if die-punch fracture is present. We aimed to evaluate the curative effect of homeopathic ankle dislocation on the unstable trimalleolar fractures involving posterior die-punch fragments. METHODS: A total of 124 patients diagnosed with unstable trimalleolar fractures combined with post-die punch fragment between June 2008 and June 2020 were retrospectively included. Patients who received homeopathic ankle dislocation were named as the experimental group, and patients who accepted conventional treatment were control group. The fracture healing time, wound healing, American Orthopedic Foot and Ankle Society ankle-hindfoot scale (AOFAS), visual analogue scale (VAS), the Kellgren-Lawrence arthritis grading scale (KLAGS) and short-form 36 score (SF-36) scores were collected. Student t-test was used for fracture healing time. Wound healing and SF-36 were compared using the Mann-Whitney test. Repeated measurement analysis of variance (ANOVA) was used for AOFAS and VAS. χ2-test was used for KLAGS. RESULTS: AOFAS showed statistically significant differences between the two groups (p = 0.001). In non-weight-bearing and weight-bearing conditions, VAS scores were significant different between the two groups, and there was an interaction between group and time point (p < 0.001). The experimental group was superior to the control group in terms of physical function (p = 0.022), role-physical (p = 0.018), general health (p = 0.001) and social function (p = 0.042).The operation time of experimental group was shorter than that of control group (p < 0.001). CONCLUSION: Homeopathic ankle dislocation is used for the unstable trimalleolar fractures involving posterior die-punch fragment, which can provide better functional outcomes while shortening the operation time and recovery period.


Subject(s)
Ankle Fractures , Humans , Retrospective Studies , Male , Female , Ankle Fractures/surgery , Adult , Middle Aged , Joint Dislocations/surgery , Fracture Healing , Homeopathy , Materia Medica/therapeutic use , Young Adult
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