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1.
Inorg Chem ; 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38917407

RESUMEN

The InP-based quantum dots (QDs) have attracted much attention in the field of photocatalytic H2 evolution. However, a shell should be used for InP-based photocatalytic systems to passivate the numerous surface defects. Different from the traditional InP-based core/shell QDs with Type-I or Type-II band alignment, herein, the "reverse Type-II" core/shell QDs in which both the conduction and valence bands of shell materials are more negative than those of core materials have been well-designed by regulating the ratio of Cd/Zn of the alloyed ZnxCd1-xS shell. The reverse Type-II band alignment would realize the spatial separation of photogenerated carriers. More importantly, the photogenerated holes tend to rest on the shell in the reverse Type-II QDs, which facilitate hole transfer to the surface, the rate-determining step for solar H2 evolution using QDs. Therefore, the obtained InP/Zn0.25Cd0.75S core/shell QDs exhibit superior photocatalytic activity and stability under visible light irradiation. The rate of solar H2 evolution reaches 376.19 µmol h-1 mg-1 at the initial 46 h, with a turnover number of ∼2,157,000 per QD within 70 h irradiation.

2.
Gastric Cancer ; 25(3): 503-514, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34826008

RESUMEN

BACKGROUND: Fibroblasts are the predominant cell type in the stroma of tumor, and cancer-associated fibroblasts (CAFs) promote cancer chemoresistance by secreting various bioactive molecules. However, the differential expression between CAFs and normal fibroblasts (NFs) and how can CAFs uniquely impact cancer cells are still unexplored. METHODS: Primary CAFs and NFs were cultured from gastric cancer specimens, and their variant expression was analyzed by RNA-sequencing. Chemoresistance was evaluated by measuring cell viability, apoptosis, and 3D-coculture techniques. RESULTS: CAFs were isolated from gastric cancers and defined by specific cell-surface markers. CAFs decreased the sensitivity of gastric cancer cells to 5-FU. RNA-sequencing showed that CAFs expressed a higher level of NRP2 than NFs. And the high expression of NRP2 was correlated with worse oncological outcomes in gastric cancer patients. Further study showed that the knockdown of NRP2 eradicated the resistance to 5-FU. And the secretion of stromal cell-derived factor-1 (SDF-1) was reduced following NRP2 knockdown. Furthermore, we found that the increased sensitivity to 5-FU was induced by DNA damage. And this process was mediated by predominant effectors of the Hippo pathway, YAP/TAZ. CONCLUSIONS: The present study indicated that CAFs within gastric cancers promote chemoresistance through the expression of NRP2. The secretion of SDF-1 that mediated by VEGF/NRP2 signaling in CAFs and the activation of Hippo pathway in cancer cells in large part participated in this project.


Asunto(s)
Fibroblastos Asociados al Cáncer , Neoplasias Gástricas , Fibroblastos Asociados al Cáncer/patología , Línea Celular Tumoral , Proliferación Celular/fisiología , Resistencia a Antineoplásicos , Fibroblastos/patología , Fluorouracilo/farmacología , Humanos , ARN/metabolismo , Neoplasias Gástricas/patología
3.
Cancer Cell Int ; 21(1): 638, 2021 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-34844630

RESUMEN

BACKGROUND: The emergence of chemoresistance to 5-fluorouracil (5-FU)-based chemotherapy is the main cause of treatment failure in advanced and metastatic colorectal cancer (CRC) patients. Long noncoding RNAs (lncRNAs) have been reported to be involved in 5-FU resistance. Previously, we first detected that lncRNA cetuximab resistance-associated RNA transcript 16 (CRART16) could contribute to cetuximab resistance by upregulating V-Erb-B2 erythroblastic leukemia viral oncogene homologue 3 (ERBB3) expression by sponging miR-371a-5p in CRC cells. The current study aimed to explore the role of CRART16 in acquired 5-FU resistance in CRC cells and its possible mechanism. METHODS: Quantitative real-time PCR (RT-qPCR) was used to measure the expression levels of CRART16 in a 5-FU-resistant CRC cell subline (SW620/5-FU) and the parent cell line. Lentivirus transduction was performed to establish SW620 and Caco-2 cells stably overexpressing CRART16. Cell Counting Kit-8 (CCK-8) assays and colony formation assays were applied to measure cell chemosensitivity to 5-FU. Flow cytometric and immunofluorescence staining were adopted to assess cell apoptosis induced by 5-FU. The dual-luciferase reporter assay was used to validate the direct interactions between CRART16 and miR-193b-5p and between miR-193b-5p and high-mobility group AT-hook-2 (HMGA2). The expression levels of HMGA2, apoptosis-associated proteins and p-ERK were examined by western blotting. The statistical differences within any two groups were used Student's t test. RESULTS: CRART16 was upregulated in SW620/5-FU cells. Overexpression of CRART16 reduced the sensitivity of CRC cells to 5-FU by attenuating apoptosis. In addition, CRART16 promoted 5-FU resistance by suppressing the expression of miR-193b-5p. Furthermore, CRART16 modulated the expression of HMGA2 by inhibiting miR-193b-5p and activated the MAPK signaling pathway. CONCLUSIONS: CRART16 confers 5-FU resistance in CRC cells through the CRART16/miR-193b-5p/HMGA2/MAPK pathway.

4.
Molecules ; 27(1)2021 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-35011284

RESUMEN

Hollow-structured mesoporous silica has wide applications in catalysis and drug delivery due to its high surface area, large hollow space, and short diffusion mesochannels. However, the synthesis of hollow structures usually requires sacrificial templates, leading to increased production costs and environmental problems. Here, for the first time, amino-functionalized mesoporous silica hollow spheres were synthesized by using CO2 gaseous bubbles as templates. The assembly of anionic surfactants, co-structure directing agents, and inorganic silica precursors around CO2 bubbles formed the mesoporous silica shells. The hollow silica spheres, 200-400 nm in size with 20-30 nm spherical shell thickness, had abundant amine groups on the surface of the mesopores, indicating excellent applications for CO2 capture, Knoevenagel condensation reaction, and the controlled release of Drugs.

5.
Cancer Cell Int ; 20: 68, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32158358

RESUMEN

BACKGROUND: Long noncoding RNAs (lncRNAs) have been shown to participate in multiple biological processes and confer drug resistance. However, it remains unclear whether lncRNAs are involved in conferring cetuximab resistance in colorectal cancer (CRC) cells. METHODS: Cell Counting Kit-8 (CCK-8) assays were performed to assess the sensitivity of CRC cell lines to cetuximab treatment. We incubated Caco-2 cells, which are partially responsive to cetuximab, with increasing concentrations of cetuximab for approximately 6 months to generate Caco-2 cetuximab-resistant (Caco-2 CR) cells. Microarray analysis comparing Caco-2 CR with Caco-2 cells was used to identify lncRNAs that were potentially related to cetuximab resistance. Caco-2 cells were stably transduced with cetuximab resistance-associated RNA transcript 16 (CRART16) or an empty vector using lentiviral infection; the cells were designated Caco-2-CRART16 and Caco-2-NC, respectively, and were analyzed with RNA sequencing (RNA-seq). Quantitative real-time PCR (qRT-PCR) was performed to investigate RNA expression. Flow cytometry and TUNEL assays were used to assess apoptosis levels induced by cetuximab. The cell cycle, stemness biomarkers and membrane proteins of CRC cells were assessed via flow cytometry. RNA fluorescence in situ hybridization (FISH) was used to examine CRART16 localization and expression. Bioinformatics analysis was performed to predict the potential mechanism of CRART16, which was further validated by a dual-luciferase reporter assay. Differences in measurement data were compared using Student's t test, one-way ANOVA followed by Dunnett's test and two-way ANOVA. RESULTS: The novel lncRNA CRART16 was upregulated in Caco-2 CR cells. CRART16 overexpression reversed the effects of cetuximab on cell viability and reduced cetuximab-induced apoptosis. Meanwhile, CRART16 overexpression led to increases in the proportion of CD44+/CD133+ cells. In addition, CRART16 acts as a competing endogenous RNA (ceRNA) for miR-371a-5p to regulate V-Erb-B2 Erythroblastic Leukemia Viral Oncogene Homolog 3 (ERBB3) expression. MiR-371a-5p mimics counteracted the cetuximab resistance induced by CRART16 overexpression. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that after CRART16 was overexpressed, the resulting differentially expressed mRNAs were mainly enriched in the MAPK signaling pathway. CONCLUSIONS: CRART16 overexpression may contribute to cetuximab resistance through the miR-371a-5p/ERBB3/MAPK pathway. Additionally, CRART16 contributes to the acquisition of stemness properties.

6.
Langmuir ; 36(8): 1851-1863, 2020 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-32036669

RESUMEN

Hierarchically porous materials have attracted great attention because of their potential applications in the fields of adsorption, catalysis, and biomedical systems. The art of manipulating different templates that are used for pore construction is the key to fabricating desired hierarchically porous structures. In this feature article, the polyelectrolyte-surfactant mesomorphous complex templating (PSMCT) approach, which was first developed by our group, is elaborated on. During the organic-inorganic self-assembly, the mesomorphous complex of the polyelectrolyte and oppositely charged surfactants would undergo in situ phase separation, which is the key to fabricating hierarchically porous materials. The recent progress in the utilization of the PSMCT method for the synthesis of hierarchically porous materials with tunable morphologies, mesophases, pore structures, and compositions is reviewed. Meanwhile, the functions of the hierarchically porous materials synthesized by the PSMCT method and their applications in adsorption, catalysis, drug delivery, and nanocasting are also briefly summarized.

7.
Small ; 12(17): 2334-43, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26900671

RESUMEN

A highly porous metal-organic framework (MOF) incorporating two kinds of second building units (SBUs), i.e., dimeric paddlewheel (Zn2 (COO)4 ) and tetrameric (Zn4 (O)(CO2 )6 ), is successfully assembled by the reaction of a tricarboxylate ligand with Zn(II) ion. Subsequently, single-crystal-to-single-crystal metal cation exchange using the constructed MOF is investigated, and the results show that Cu(II) and Co(II) ions can selectively be introduced into the MOF without compromising the crystallinity of the pristine framework. This metal cation-exchangeable MOF provides a useful platform for studying the metal effect on both gas adsorption and catalytic activity of the resulted MOFs. While the gas adsorption experiments reveal that Cu(II) and Co(II) exchanged samples exhibit comparable CO2 adsorption capability to the pristine Zn(II) -based MOF under the same conditions, catalytic investigations for the cycloaddition reaction of CO2 with epoxides into related carbonates demonstrate that Zn(II) -based MOF affords the highest catalytic activity as compared with Cu(II) and Co(II) exchanged ones. Molecular dynamic simulations are carried out to further confirm the catalytic performance of these constructed MOFs on chemical fixation of CO2 to carbonates. This research sheds light on how metal exchange can influence intrinsic properties of MOFs.

8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(11): 2961-7, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25752039

RESUMEN

There are many hydrogen bonds in coal, which affect the chemical structure and properties of coal. FTIR has been applied to the characterization study of the hydrogen bonds of Dongpang coals, which were under drop weight impact. There exists five kinds of hydrogen bonds in the coal: free OH groups, OH...π, OH...OH, cyclic OH tetramers and OH...N. Absorption strength of intermolecular hydrogen bonds markedly declined after impact. Free OH groups mechanical-power chemical reacted in drop weight impact testing. The infrared spectrum were curve-resolved into their component bands. The absorption strength of various hydrogen bonds decreased with the increase of impact energy, but the trend was slowing. By statistical relationship between then, we find then complying with power function relationship. By comparing the exponents of fitted equations, we concluded that failure sensitivity sequence of hydrogen bonds to the impact: free OH groups > cyclic OH tetramers > OH...N > OH...π > OH...OH.

9.
Heliyon ; 10(4): e26501, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38420488

RESUMEN

A crucial industry for improving society's sustainable development is the power sector. To address issues with the ineffectiveness of electric power emergency response during emergencies and the unclear division of duty among emergency subjects. A prefecture-level city power supply company to respond to the "In-Fa" typhoon, for example, to build a "1 + N" two-level emergency rapid response unit. Furthermore, it is proposed from the emergency response, emergency coordination, emergency material reserves, etc., to build a "full-chain" type of power emergency quick reaction system. Case studies have revealed that the quick response system's emergency combat capability, catastrophe preventive and mitigation capability, and emergency security capability have all improved. The construction of a "full-chain" type of power emergency rapid response system specialized and standardized the power emergency response system and provided a reference basis for the power industry's emergency response.

10.
ChemSusChem ; : e202400832, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38845094

RESUMEN

The performance of zinc-air battery is constrained by the sluggish rate of oxygen electrode reaction, particularly under high current discharge conditions where the kinetic process of the oxygen reduction reaction (ORR) decelerates significantly. To address this challenge, we present a novel phase transition strategy that facilitates the creation of a heteroatom-doped heterointerface (CoN/CoS2). The meticulously engineered CoN/CoS2/NC electrocatalyst displays a superior ORR half-wave potential of 0.87 V and an OER overpotential of 320 mV at 10 mA cm-2. Experimental and computational analysis confirm that the CoN/CoS2 heterostructure optimizes local charge distribution, accelerates electron transfer, and tunes active sites for enhanced catalysis. Notably, this heterojunction improves stability by resisting corrosion and degradation under harsh alkaline conditions, thus demonstrating superior performance and longevity in a custom-made liquid zinc-air battery. This research provides valuable practical and theoretical foundations for designing efficient heterointerfaces in electrocatalysis applications.

11.
Am J Transl Res ; 16(2): 599-616, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38463603

RESUMEN

OBJECTIVE: This study aimed to analyze the efficacy of acupuncture alone or combined with physical therapy compared to other treatment interventions for relieving pain and improving function in rotator cuff diseases. METHODS: Our study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. After PROSPERO (CRD42023396740) registration, all randomized controlled trials (RCTs) published from the inception of the databases to October 10, 2023, evaluating the efficacy of acupuncture either alone or in combination with physical therapy for treating rotator cuff diseases, were extracted from seven databases, including PubMed, Embase, the Web of Science, the Cochrane Library, the China National Knowledge Infrastructure (CNKI), the VIP Database for Chinese Technical Periodicals (VIP), and the Wanfang Date. Two independent researchers assessed the quality of the included studies and extracted relevant data. Furthermore, a meta-analysis was conducted using Stata 14 software. RESULTS: We included 13 RCTs - 12 published in English and 1 in Chinese - that enrolled 1,371 patients. The meta-analysis results demonstrated that acupuncture alone or in combination with physical therapy was superior to other interventions for short-term shoulder joint function improvement (standardized mean difference [SMD] = -0.82, 95% confidence interval [95% CI]: -1.28 to -0.35, P = 0.001), medium-term shoulder joint function improvement (SMD = -1.00, 95% CI: -1.62 to -0.38, P = 0.002), short-term pain relief (weighted mean difference [WMD] = -1.37, 95% CI: -2.39 to -0.38, P = 0.006), medium-term pain relief (WMD = -1.66, 95% CI: -2.70 to -0.63, P = 0.002), and post-treatment shoulder joint abduction improvements (SMD = 0.68, 95% CI: 0.20 to 1.16, P = 0.005), external rotation (SMD = 0.62, 95% CI: 0.13 to 1.11, P = 0.012), and forward flexion (SMD = 0.71, 95% CI: 0.44 to 0.97, P < 0.001), with significant differences (P < 0.05). CONCLUSION: Based on the current clinical data, meta-analysis showed that acupuncture alone or combined with physical therapy is efficacious for short- and medium-term (< 3 months) pain relief and functional improvements. However, compared to other interventions, the efficacy of the long-term (3 to 12 months) period did not significantly differ. After treatment, these modalities displayed advantages such as improved shoulder joint abduction, external rotation, and forward flexion movements. However, no significant difference was noted in internal rotation movement. Thus, future studies might further investigate whether different acupuncture methods affect the efficacy of treating rotator cuff diseases and improving long-term outcome.

12.
Aging (Albany NY) ; 15(13): 6545-6576, 2023 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-37450415

RESUMEN

BACKGROUND: Ubiquitin Specific Peptidase 28 (USP28), as a member of the DUBs family, has been reported to regulate the occurrence and development of some tumors, but its oncogenic role in tumor immunity is still unknown. METHODS: The comprehensive view of USP28 expression in tumor and normal samples was obtained from public databases, including The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), and Cancer Cell Line Encyclopedia (CCLE). We analyzed the genomic alterations of USP28 in various cancers using the cBioPortal dataset. Besides, gene set enrichment analysis was used to analyze the associated cancer hallmarks with USP28 expression, and TIMER2.0 was taken to investigate the immune cell infiltrations related to the USP28 level. RESULTS: USP28 is highly expressed in most tumors and has prognostic value across various cancer types. Moreover, a significant correlation exists between USP28 and immune regulators, clinical staging, checkpoint inhibitor response, MSI, TMB, CNV, MMR defects, and DNA methylation. Additionally, USP28 expression is strongly associated with the infiltration levels of neutrophils and NK cells in most tumor types. One of the most significant findings of our study was that USP28 could serve as a significant predictor of anti-CTLA4 therapy response in melanoma patients. Additionally, our molecular biology experiments validated that the knockdown of USP28 substantially reduced the proliferative and invasive abilities of the HCC cell lines. CONCLUSIONS: Our study suggests that USP28 could potentially serve as a biomarker for cancer immunologic infiltration and poor prognosis, with potential applications in developing novel cancer treatment strategies.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Pronóstico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Línea Celular , Proteasas Ubiquitina-Específicas , Ubiquitina Tiolesterasa
13.
Aging (Albany NY) ; 15(24): 15504-15524, 2023 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-38157278

RESUMEN

BACKGROUND: VRK1 is a member of the vaccinia-related kinase (VRK) family of serine/threonine protein kinases, which is related to the occurrence and development of malignant tumors. The expression pattern, predictive value, and biological function of VRK1 in various cancers remain largely elusive and warrant further investigation. METHODS: Public databases, such as TCGA, GTEx, and UCEC, were utilized to comprehensively analyze the expression of VRK1 across multiple cancer types. Prognostic significance was assessed through Univariate Cox regression and Kaplan-Meier analyses. Additionally, Spearman's correlation analysis was employed to explore the potential associations between VRK1 expression and various factors, including tumor microenvironment scores, immune cell infiltration, and immune-related genes. Moreover, to validate the findings, differential expression of VRK1 in HCC tissues and cell lines was further confirmed using qPCR, Western blot, and immunohistochemistry techniques. RESULTS: The upregulation of VRK1 was observed in most cancer types, and was associated with worse prognosis in ACC, KICH, KIRP, LGG, LIHC, LUAD, MESO, and PCPG. In various cancers, VRK1 expression exhibited positive correlations with immune infiltrating cells, immune checkpoint-related genes, TMB, and MSI. Furthermore, the promoter methylation status of VRK1 varied across different tumor types, and this variation was associated with patient prognosis in certain cancers. In our experimental analyses, we observed significantly elevated expression of VRK1 in both HCC tissues and HCC cells. Functionally, we found that the downregulation of VRK1 had a profound impact on HCC cells, leading to a significant decrease in their proliferation, migration, and invasion capabilities. CONCLUSION: The expression of VRK1 exerts a notable influence on the prognosis of several tumors and exhibits a strong correlation with tumor immune infiltration. Moreover, in the context of HCC, VRK1 may act as an oncogene, actively promoting tumor progression.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Vaccinia , Humanos , Carcinoma Hepatocelular/genética , Proteínas Serina-Treonina Quinasas/genética , Pronóstico , Neoplasias Hepáticas/genética , Serina , Microambiente Tumoral/genética , Péptidos y Proteínas de Señalización Intracelular
14.
Nanomaterials (Basel) ; 13(16)2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37630881

RESUMEN

Lewis acid zeolites play an important role in industrially important green reactions closely related to fine chemical and biomass conversion. Titanium-doped TS-1 zeolite is a milestone Lewis acid zeolite widely used in industrially significant green oxidation processes with hydrogen peroxide as an oxidant under mild conditions. TS-1 zeolites are normally synthesized in basic conditions under hydrothermal treatment. Up to now, there has still been no success in synthesizing active TS-1 Lewis acid zeolites by using inorganic alkali, e.g., NaOH or KOH as base, which is cheaper and more stable compared to the quaternary ammonium hydroxide or organic amines used in traditional synthesis. Here, an inorganic base of NaOH was employed in synthesizing active TS-1 zeolites for the first time. The crucial factor was the control of adverse effects of sodium cations on the incorporation of active titanium cations. Higher catalytic activity was achieved by further reducing the size of the TS-1 crystal by using the seed-added strategy, which uses the catalytic activity of a commercial catalyst, the production cost being much lower than commercial TS-1 catalysts, indicating great commercial potential and the possibility of preparing other cheap Lewis acid catalysts by using inorganic alkali.

15.
Medicine (Baltimore) ; 102(51): e36655, 2023 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-38134093

RESUMEN

BACKGROUND: To evaluate the effects and safety of pediatric tuina for recurrent respiratory tract infections (RRTIs). METHODS: Web of Science, PubMed, Cochrane Library, Embase, CNKI, Wanfang Data, VIP, and CBM databases were searched from inception to September 20 2023. Two authors independently selected studies, collected data, and evaluated methodological quality using the Cochrane Risk of Bias tool. Revman 5.4 was used for the meta-analysis. RESULTS: Fifteen randomized controlled trials involving 1420 pediatric patients were included in this meta-analysis. The meta-analysis indicated that pediatric tuina significantly reduced the incidence of RRTIs [MD -1.11, 95% confidence interval (CI) (-1.77, -0.46)], decreased infection duration (MD -1.16 days, 95% CI [- 1.66, - 0.66]), improved IgA (MD 0.25 g/L, 95% CI [0.09, 0.41]), IgG (MD 1.64 g/L; 95% CI [0.82, 2.45]), CD3+ (MD 3.33%, 95% CI [0.74, 5.92]), CD4+ (MD 4.78%, 95% CI [2.08, 7.48]), CD4+/CD8+ ratio (MD 0.27%, 95% CI [0.08, 0.47]), and total effective rate (RR 1.19, 95% CI [1.13, 1.25]). However, IgM levels (MD 0.26 g/L, 95% CI [-0.26, 0.81]) and CD8+ (MD -1.36%, 95% CI [- 3.12, 0.41]) were not significantly different between the groups. Moreover, no Tuina-linked adverse reactions were observed. CONCLUSION: Pediatric tuina has shown positive effects in RRTIs treatment. However, these results should be interpreted with caution owing to study quality. Further large-scale and high-quality randomized controlled trials are warranted to confirm these findings.


Asunto(s)
Infecciones del Sistema Respiratorio , Niño , Humanos , Relación CD4-CD8 , Ensayos Clínicos Controlados Aleatorios como Asunto
16.
Nanomaterials (Basel) ; 13(13)2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37446438

RESUMEN

Titanium silicalite-1 (TS-1) is a milestone heterogeneous catalyst with single-atom tetrahedral titanium incorporated into silica framework for green oxidation reactions. Although TS-1 catalysts have been industrialized, the strategy of direct hydrothermal synthesis usually produces catalysts with low catalytic activities, which has still puzzled academic and industrial scientists. Post-treatment processes were widely chosen and were proven to be an essential process for the stable production of the high-activity zeolites with hollow structures. However, the reasons why post-treatment processes could improve catalytic activity are still not clear enough. Here, high-performance hollow TS-1 zeolites with nano-sized crystals and nano-sized cavities were synthesized via post-treatment of direct-synthesis nano-sized TS-1 zeolites. The influencing factors of the fabricating processes on their catalytic activities were investigated in detail, including the content of alkali metal ions, the state of titanium centers, hydrophilic/hydrophobic properties, and accessibility of micropores. The post-treatment processes could effectively solve these adverse effects to improve catalytic activity and to stabilize production. These findings contribute to the stable preparation of high-performance TS-1 catalysts in both factories and laboratories.

17.
Chem Sci ; 14(24): 6564-6571, 2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37350827

RESUMEN

Ligand shells of gold nanoclusters play important roles in regulating their molecular and electronic structures. However, the similar but distinct impacts of the homologous analogues of the protecting ligands remain elusive. The C2v symmetric monoarsine-protected cluster [Au13(AsPh3)8Cl4]+ (Au13As8) was facilely prepared by direct reduction of (Ph3As)AuCl with NaBH4. This cluster is isostructural with its previously reported stibine analogue [Au13(SbPh3)8Cl4]+ (Au13Sb8), enabling a comparative study between them. Au13As8 exhibits a blue-shifted electronic absorption band, and this is probably related to the stronger π-back donation interactions between the Au13 core and AsPh3 ligands, which destabilize its superatomic 1P and 1D orbitals. In comparison to the thermodynamically less stable Au13Sb8, Au13As8 achieves a better trade-off between catalytic stability and activity, as demonstrated by its excellent catalytic performance towards the aldehyde-alkyne-amine (A3) coupling reaction. Moreover, the ligand exchange reactions between Au13As8 with phosphines, as exemplified by PPh3 and Ph2P(CH2)2PPh2, suggest that Au13As8 may be a good precursor cluster for further cluster preparation through the "cluster-to-cluster" route.

18.
Medicine (Baltimore) ; 102(45): e36010, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37960757

RESUMEN

RATIONALE: Gefitinib is a potent and selective orally active growth factor receptor (EGFR)-tyrosine kinase inhibitor that is commonly used to treat advanced non-small cell lung cancer patients with activating EGFR mutations. Hearing impairment with gefitinib was sparsely reported. In this report, we describe a case of sensorineural deafness associated with the administration of gefitinib, with a Naranjo score of 7. PATIENT CONCERNS: An 81-year-old female was diagnosed with lung adenocarcinoma with bone metastasis and an EGFR-activating mutation. The patient was prescribed gefitinib tablets at a daily dose of 250 mg for lung adenocarcinoma treatment. However, the patient experienced moderate to severe bilateral sensorineural deafness, primarily in her right ear, after taking gefitinib. Following the cessation of gefitinib administration, the patient exhibited partial restoration of auditory function. Upon resuming the medication, she experienced a worsening of deafness. DIAGNOSES: The otoscopic audiogram and hearing test indicated moderate to severe bilateral sensorineural deafness. INTERVENTIONS: The otolaryngologist recommended bilateral hearing aids to enhance hearing function. OUTCOMES: Throughout our follow-up period, the patient did not receive a hearing aid implant. LESSONS: This article first reported the ototoxicity caused by gefitinib. While rare, our report highlights that gefitinib-induced sensorineural deafness is possible and its mechanisms are still unclear. This adverse reaction should be monitored closely during clinical application of gefitinib to improve patient outcomes.


Asunto(s)
Adenocarcinoma del Pulmón , Carcinoma de Pulmón de Células no Pequeñas , Sordera , Pérdida Auditiva Sensorineural , Neoplasias Pulmonares , Humanos , Femenino , Anciano de 80 o más Años , Gefitinib/efectos adversos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/patología , Pérdida Auditiva Sensorineural/inducido químicamente , Receptores ErbB/metabolismo , Mutación
19.
Langmuir ; 28(23): 8600-7, 2012 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-22650968

RESUMEN

Mesoporous zeolite silicalite-1 and Al-ZSM-5 with intracrystalline mesopores were synthesized with polyelectrolyte-surfactant complex as the template. Complex colloids were first formed by self-assembly of the anionic polymer poly(acrylic acid) (PAA) and the cationic surfactant cetyltrimethylammonium bromide (CTAB) in basic solution. During the synthesis procedure, upon the addition of the silica source, microporous template (tetrapropylammonium hydroxide), and NaCl, these PAA/CTA complex colloids underwent dissociation and gave rise to the formation of hollow silica spheres with mesoporous shells templated by CTAB micelles and PAA domains as the core. Under hydrothermal treatment, the hollow silica spheres gradually merged together to form larger particles with the PAA domains embedded as the space occupant, which acted as a template for intracrystalline mesopores during the crystallization of the zeolite framework. Amphiphilic organosilane was used to enhance the connection between the PAA domain and the silica phase during the synthesis. After calcination, single crystal-like zeolite particles with intracrystalline mesopores of about 5-20 nm were obtained, as characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and N(2) adsorption measurements. With the addition of an aluminum source in the synthesis, mesoporous zeolite Al-ZSM-5 with intracrystalline mesopores was also synthesized, and enhanced catalytic property was observed with mesoporous Al-ZSM-5 in acetalization of cyclohexanone with methanol.

20.
Pain Res Manag ; 2022: 8331439, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36213180

RESUMEN

Background: Irritable bowel syndrome (IBS) is a clinical disease mainly characterized as a syndrome of abdominal pain and discomfort, which frequently occurs in humans aged 20-50. Abdomen massage is of great medical significance for the health of the human body, including promoting intestinal peristalsis, relieving constipation, and facilitating weight loss. However, its potential benefits in alleviating IBS and the underlying mechanisms remain elusive. Methods: In this study, we established an IBS model in rats to evaluate the effects of abdomen massage. Forty male Sprague Dawley (SD) rats were randomly assigned into 4 groups: the normal (control) group, IBS group, abdominal massage group, and abdominal massage + ketotifen treatment group (n = 10 rats in each group). Abdominal massage was performed once a day for 5 minutes for 14 days. On day 14, the rats were euthanized and the tissues were analyzed by transmission electron microscopy (TEM), immunohistochemistry or immunofluorescence staining, and laser confocal focus to visualize the micromorphology of the intestinal mucosa. The expression of TRPV1 and the release of trypase were determined by RT-qPCR and western blot. Results: We found that compared with the control group, the mast cells in the IBS group were significantly increased and the increased MC was partially decreased by an abdominal massage with or without ketotifen treatment. We also found that TRPV1 was upregulated in the IBS group. Abdominal massage with or without ketotifen treatment could attenuate the upregulation of TRPV1 in IBS. Mechanically, results of IHC and western Blot suggested that abdominal massage reduces the sensitivity of IBS by regulating the trypase-PAR2-PKCε pathway. Conclusion: Overall, our results suggested that abdominal massage produces a beneficial effect in improving the symptoms of IBS through reducing mast cell recruitment and attenuating the trypase-PAR2-PKCε pathway. Ketotifen could promote the effect of abdominal massage on IBS treatment, which can serve as a potential therapeutic strategy for IBS.


Asunto(s)
Síndrome del Colon Irritable , Animales , Humanos , Síndrome del Colon Irritable/terapia , Cetotifen/metabolismo , Cetotifen/farmacología , Cetotifen/uso terapéutico , Masculino , Masaje , Mastocitos/metabolismo , Proteína Quinasa C-epsilon/metabolismo , Ratas , Ratas Sprague-Dawley
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