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1.
Inorg Chem ; 63(19): 8615-8624, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38668738

RESUMEN

The design and synthesis of stable porous materials capable of removing both hard and soft metal ions pose a significant challenge. In this study, a novel metal-organic framework (MOF) adsorbent named CdK-m-COTTTB was developed. This MOF material was constructed using sulfur-rich m-cyclooctatetrathiophene-tetrabenzoate (m-H4COTTTB) as the organic ligand and oxygen-rich bimetallic clusters as the inorganic nodes. The incorporation of both soft and hard base units within the MOF structure enables effective removal of various heavy metal ions, including both soft and hard acid species. In single-component experiments, the adsorption capacity of CdK-m-COTTTB for Pb2+, Tb3+, and Zr4+ ions reached levels of 636.94, 432.90, and 357.14 mg·g-1, respectively, which is comparable to specific MOF absorbents. The rapid adsorption process was found to be chemisorption. Furthermore, CdK-m-COTTTB exhibited the capability to remove at least 12 different metal ions in both separate and multicomponent solutions. The material demonstrated excellent acid-base stability and renewability, which are advantageous for practical applications. CdK-m-COTTTB represents the first reported pristine MOF material for the removal of both hard and soft acid metal ions. This work serves as inspiration for the design and synthesis of porous crystalline materials that can efficiently remove diverse heavy metal pollutants.

2.
Exp Cell Res ; 432(2): 113778, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37741489

RESUMEN

While YTH N6-methyladenosine RNA binding protein 1 (YTHDF1) was recognized as a crucial contributor in the development and immune-related regulation of various types of tumors, its function in the immune response of breast cancer has largely remained uninvestigated. Through analysis of public databases, we found YTHDF1 as a highly expressed gene in breast cancers and confirmed this finding in breast cancer cells and clinical specimens from our center. Subsequently, we examined the link between YTHDF1 expression and immune cells and molecules by utilizing immune-related public databases and algorithm. We further validated our findings through cellular and animal experiments, as well as RNA sequencing. YTHDF1 was found highly expressed in tumor tissues of breast cancer, which negatively correlated with patient survival. The downregulation of YTHDF1 promoted the expression of pro-inflammatory markers and improved the anti-cancer ability of immune cells in breast cancer. RNA sequencing analysis revealed that YTHDF1 knockdown resulted in enrichment of differential genes in signal transduction pathways. Additionally, in vitro experiments showed that immune cells had higher cytotoxicity against breast cancer cells with decreased YTHDF1 expression. Moreover, in vivo studies indicated that YTHDF1 promoted breast cancer growth while inhibiting CD8+ T cell infiltration and function. Our study demonstrates that YTHDF1 plays a crucial role in establishing a "cold" tumor microenvironment in breast cancer by inhibiting the release of pro-inflammatory cytokines from cancer cells. As a result, the infiltration and functional differentiation of anti-tumor CD8+ T cells are hindered, ultimately resulting in the immune evasion of breast cancer.

3.
Angew Chem Int Ed Engl ; 63(16): e202401679, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38389160

RESUMEN

Electrically conductive metal-organic frameworks (cMOFs) have garnered significant attention in materials science due to their potential applications in modern electrical devices. However, achieving effective modulation of their conductivity has proven to be a major challenge. In this study, we have successfully prepared cMOFs with high conductivity by incorporating electron-donating fused thiophen rings in the frameworks and extending their π-conjugated systems through ring-closing reactions. The conductivity of cMOFs can be precisely modulated ranging from 10-3 to 102 S m-1 by regulating their dimensions and topologies. Furthermore, leveraging the inherent tunable electrical properties based on topology, we successfully demonstrated the potential of these materials as chemiresistive gas sensors with an outstanding response toward 100 ppm NH3 at room temperature. This work not only provides valuable insights into the design of functional cMOFs with different topologies but also enriches the cMOF family with exceptional conductivity properties.

4.
Breast J ; 2023: 9035266, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37435101

RESUMEN

Background: Intraoperative radiotherapy (IORT) is a novel promising technology that may replace external beam radiation therapy (EBRT) as boost for patients receiving breast-conserving surgery. To better evaluate the efficacy of IORT using low-kilovoltage (low-kV) X-rays as boost, we presented this meta-analysis according to the PRISMA checklist. Methods: Studies reported survival outcomes of intraoperative radiation using low-kilovoltage X-rays system (Intrabeam®, Carl Zeiss Meditec, Dublin, CA, USA) as boost were identified through electronic bibliographic database: PUBMED. The meta-analysis module in Stata (16.0) is used to pool the studies. A Poisson regression model is used to predict a 5-year local recurrence rate. Results: Twelve studies including 3006 cases were included in the final analysis, with a median follow-up of 55 months weighted by sample size. The pooled local recurrence rate is 0.39% per person-year (95% CI: 0.15%-0.71%), with a low degree of heterogeneity (I2 = 0%). The predicted 5-year local recurrence rate was 3.45%. No difference in pooled local recurrence rate was found between non-neoadjuvant patients studies and neoadjuvant patients studies (0.41% per person-year vs. 0.58% per person-year, P = 0.580). Conclusions: This study shows that low-kV IORT is an effective method as boost in breast cancer patients, with a low pooled local recurrence rate and low predicted 5-year local recurrence rate. Besides, no difference in the local recurrence rate was found between non-neoadjuvant patients studies and neoadjuvant patients studies. Low-kV IORT boost may be a promising alternative to EBRT boost in the future, which is being tested in the ongoing TARGIT-B trial.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Rayos X , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Lista de Verificación , Mastectomía Segmentaria , Terapia Neoadyuvante
5.
J Am Chem Soc ; 144(13): 5728-5733, 2022 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-35319193

RESUMEN

The connectivity of building units for 3D covalent organic frameworks (COFs) has long been primarily 4 and 6, which have severely curtailed the structural diversity of 3D COFs. Here we demonstrate the successful design and synthesis of a porphyrin based, 8-connected building block with cubic configuration, which could be further reticulated into an unprecedented interpenetrated pcb topology by imine condensation with linear amine monomers. This study presents the first case of high-connectivity building units bearing 8-connected cubic nodes, thus greatly enriching the topological possibilities of 3D COFs.

6.
J Am Chem Soc ; 142(51): 21279-21284, 2020 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-33295765

RESUMEN

We propose a dynamic covalent chemistry (DCC)-induced linker exchange strategy for the structural transformation between covalent organic frameworks (COFs) and cages for the first time. Studies have shown that the COF-to-cage and cage-to-COF transformations were realized by using borate bonds and imine bonds, respectively, as linkages. Self-sorting experiments suggested that borate cages and imine COFs are thermodynamic minimum compounds. This research builds a bridge between discrete and polymeric organic scaffolds and broadens the knowledge of chemistry and materials for porous materials science.

7.
Cancer Cell Int ; 20: 123, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32322170

RESUMEN

BACKGROUND: Kinesin superfamily (KIFs) has a long-reported significant influence on the initiation, development, and progress of breast cancer. However, the prognostic value of whole family members was poorly done. Our study intends to demonstrate the value of kinesin superfamily members as prognostic biomarkers as well as a therapeutic target of breast cancer. METHODS: Comprehensive bioinformatics analyses were done using data from TCGA, GEO, METABRIC, and GTEx. LASSO regression was done to select tumor-related members. Nomogram was constructed to predict the overall survival (OS) of breast cancer patients. Expression profiles were testified by quantitative RT-PCR and immunohistochemistry. Transcription factor, GO and KEGG enrichments were done to explore regulatory mechanism and functions. RESULTS: A total of 20 differentially expressed KIFs were identified between breast cancer and normal tissue with 4 (KIF17, KIF26A, KIF7, KIFC3) downregulated and 16 (KIF10, KIF11, KIF14, KIF15, KIF18A, KIF18B, KIF20A, KIF20B, KIF22, KIF23, KIF24, KIF26B, KIF2C, KIF3B, KIF4A, KIFC1) overexpressed. Among which, 11 overexpressed KIFs (KIF10, KIF11, KIF14, KIF15, KIF18A, KIF18B, KIF20A, KIF23, KIF2C, KIF4A, KIFC1) significantly correlated with worse OS, relapse-free survival (RFS) and distant metastasis-free survival (DMFS) of breast cancer. A 6-KIFs-based risk score (KIF10, KIF15, KIF18A, KIF18B, KIF20A, KIF4A) was generated by LASSO regression with a nomogram validated an accurate predictive efficacy. Both mRNA and protein expression of KIFs are experimentally demonstrated upregulated in breast cancer patients. Msh Homeobox 1 (MSX1) was identified as transcription factors of KIFs in breast cancer. GO and KEGG enrichments revealed functions and pathways affected in breast cancer. CONCLUSION: Overexpression of tumor-related KIFs correlate with worse outcomes of breast cancer patients and can work as potential prognostic biomarkers.

8.
J Org Chem ; 83(19): 12154-12163, 2018 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-30173515

RESUMEN

On the basis of three new building blocks, dithieno[3,2- b:2',3'- d]selenophene ( tt-DTS), diseleno[3,2- b:2',3'- d]thiophene ( tt-DST), and diseleno[3,2- b:2',3'- d]selenophene ( tt-DSS), four thiophene- and selenophene-based heteroacenes (3a-d) with up to seven fused rings were designed and synthesized. Another two selenophene-based heteroacenes (1 and 2) with three and five fused rings were prepared. The molecular structures of 1, 2, 3a, and 3c were confirmed by single-crystal analysis. The results showed that molecular structures, spectroscopy features, and cyclic voltammetry behaviors could be modulated by changing the heteroatoms from sulfur to selenium for 3a-d or changing the numbers of selenophene rings for 1, 2, and 3d.

9.
J Org Chem ; 82(20): 11192-11197, 2017 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-28952725

RESUMEN

New building blocks, 2,5-di(trimethylsilanyl)diseleno[2,3-b:3',2'-d]selenophene ((TMS)2-DSS) and 2,5-di(trimethylsilanyl)diseleno[2,3-b:3',2'-d]thiophene ((TMS)2-DST), for helicenes were obtained from selenophene with total yields of 54 and 61%. From (TMS)2-DSS and (TMS)2-DST, selenophene-based hetero[7]helicenes, 5,5'-di(trimethylsilanyl)benzo[1,2-b:3,4-b']bis(diseleno[2,3-b:3',2'-d]thiophene) (rac-1), and 5,5'-di(trimethylsilanyl)benzo[1,2-b:3,4-b']bis(diseleno[2,3-b:3',2'-d]selenophene) (rac-2) were prepared. The overall yields from selenophene were approximately 6.5 and 6.1%, respectively. Intermolecular interactions such as C-Se, C-S, and Se-Se were observed in the crystal packings of rac-1 and rac-2. In addition, the absorption behaviors of rac-1 and rac-2 were investigated.

10.
World J Surg Oncol ; 14(1): 213, 2016 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-27514796

RESUMEN

BACKGROUND: Surgery remains the first choice of treatment for tongue cancer. Immediate reconstruction should be performed after wide resection of tumour. The aim of this study was to evaluate the anterolateral thigh flap for reconstruction of lingual defects. METHODS: We report 39 consecutive oral tongue squamous cell carcinoma patients who underwent lingual reconstruction with the anterolateral thigh flap between 2009 and 2010. RESULTS: The width of the skin island was 4 to 5 cm and the length of the skin island was 6 to 8 cm in 31 patients with T2 tumour, while the width of the skin island was 5.5 to 6 cm and the length of the skin island was 9 to 12 cm in 8 patients with T3/4 tumours. The all flap survival rate was 97.5 % in our series. CONCLUSIONS: We could obtain sufficient flap volume using the anterolateral thigh flap for tongue reconstruction. The single perforator-based anterolateral thigh flap is a good option for soft tissue reconstruction in patients with oral tongue squamous cell carcinoma.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Colgajos Tisulares Libres/trasplante , Procedimientos de Cirugía Plástica/métodos , Neoplasias de la Lengua/cirugía , Adulto , Anciano , Femenino , Supervivencia de Injerto , Humanos , Masculino , Persona de Mediana Edad , Muslo/cirugía , Resultado del Tratamiento
11.
Cell Physiol Biochem ; 36(4): 1359-70, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26159387

RESUMEN

AIMS: To explore the expression of miR-24-3p in human arteries with arteriosclerosis obliterans (ASO) as well as the role of miR-24-3p in the pathogenesis of ASO. METHODS: We used quantitative real-time PCR (qRT-PCR) and in situ hybridization to monitor miR-24-3p expression in human arteries. To investigate the effect of miR-24-3p on human arterial smooth muscle cells (HASMCs), we applied cell counting and EdU assays to monitor proliferation and transwell and wound healing assays to investigate migration and flow cytometry to investigate apoptosis. Furthermore, we applied 3'-untranslated region (3'-UTR) luciferase assays to investigate the role of miR-24-3p in targeting platelet-derived growth factor receptor B (PDGFRB) and c-Myc. RESULTS: MiR-24-3p was mainly located in the media of arteries and was downregulated in ASO arteries compared with normal arteries. Platelet-derived growth factor BB (PDGF-BB) treatment reduced the expression of miR-24-3p in primary cultured HASMCs. MiR-24-3p mimic oligos inhibited the proliferation and migration, and promotes apoptosis of HASMCs. Our 3'-UTR luciferase assays confirmed that PDGFRB and c-Myc were targets of miR-24-3p. CONCLUSION: The results suggest that miR-24-3p regulates the proliferation and migration of HASMCs by targeting PDGFRB and c-Myc. The PDGF/miR-24-3p/PDGFRB and PDGF/miR-24-3p/c-Myc pathways may play critical roles in the pathogenesis of ASO. These findings highlight the potential for new therapeutic targets for ASO.


Asunto(s)
Apoptosis , Arteriosclerosis Obliterante/genética , Movimiento Celular , Proliferación Celular , Regulación de la Expresión Génica , MicroARNs/genética , Miocitos del Músculo Liso/patología , Arteriosclerosis Obliterante/patología , Secuencia de Bases , Células Cultivadas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Miocitos del Músculo Liso/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética
12.
Yao Xue Xue Bao ; 50(5): 565-8, 2015 May.
Artículo en Zh | MEDLINE | ID: mdl-26234137

RESUMEN

The PET tracer 5-([11C]methyloxy)-L-tryptophan (5-(11)CMTP) was prepared by nucleophilic fluorination and alkylation reaction via a two-step procedure in order to develop specific tumor probe. The biodistribution and microPET imaging of 5-(11)CMTP were executed. The results unveiled that the overall radiochemical yield with no decay correction was (14.6 ±7.2) %, the radiochemical purity was more than 95% and high uptake and long retention time of 5-(11)CMTP in liver, kidney and blood were observed but low uptake in brain and muscle were found, furthermore, high uptake of 5-(11)CMTP in tumor tissue was observed. It seems that 5-(11)CMTP will be a potential amino acid tracer for tumors imaging with PET.


Asunto(s)
Neoplasias/diagnóstico por imagen , Tomografía de Emisión de Positrones , Triptófano , Aminoácidos , Animales , Trazadores Radiactivos , Distribución Tisular , Triptófano/análogos & derivados
13.
J Oral Maxillofac Surg ; 72(12): 2497.e1-10, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25454713

RESUMEN

PURPOSE: This study investigated prognostic factors and useful predictors for survival in patients with oral squamous cell carcinoma. PATIENTS AND METHODS: The medical records of all patients with oral squamous cell carcinoma who underwent curative surgery with or without adjuvant radiation from 2009 through 2011 were retrospectively reviewed. RESULTS: Seventy-seven patients (63 men and 14 women) were enrolled. The 2-year disease-free and overall survival rates were 67.5% and 74%, respectively. Multivariate analyses showed that a diagnostic delay longer than 2 months (hazard ratio [HR]=4.43; 95% confidence interval [CI], 1.26-15.51; P=.02), T3 or T4 tumor (HR=4.40; 95% CI, 1.91-10.12; P=.001), neck metastasis (HR=1.96; 95% CI, 1.21-4.37; P=.01), and stage III or IV disease (HR=3.94; 95% CI, 1.64-9.47; P=.002) were independent adverse factors for survival rate. CONCLUSION: Oral squamous cell carcinoma is an important health issue associated with poor survival. A diagnostic delay longer than 2 months, T3 or T4 tumor, neck metastasis, and stage III or IV disease were independent adverse factors for subsequent survival rate and locoregional recurrence in patients with oral squamous cell carcinoma.


Asunto(s)
Carcinoma de Células Escamosas/fisiopatología , Neoplasias de la Boca/fisiopatología , Tasa de Supervivencia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
14.
Quant Imaging Med Surg ; 14(3): 2391-2404, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38545047

RESUMEN

Background: Metastatic burden of sentinel lymph node (SLN) in breast cancer patient is the basis for the decision to choose SLN biopsy or axillary lymph node dissection (ALND). However, the diagnostic performance of the previous percutaneous contrast-enhanced ultrasound (P-CEUS) and intravenous contrast-enhanced ultrasound (IV-CEUS) pattern were not satisfied. This study aimed to establish new classification based on structural characteristics for P-CEUS and IV-CEUS of SLN in breast cancer and evaluate the diagnostic efficacy. Methods: This retrospective study included consecutive breast cancer patients who had not received neoadjuvant therapy in the First Affiliated Hospital of Sun Yat-sen University between June 2019 and December 2021. Conventional ultrasound, P-CEUS and IV-CEUS were performed. The new classification methods for P-CEUS and IV-CEUS of SLN were established based on structural characteristics of SLN. Pathology was considered as the gold standard, the diagnostic efficacy of P-CEUS, IV-CEUS and combined contrast-enhanced ultrasound in SLNs was analyzed. Results: The detection rate of SLN by P-CEUS in 368 patients was 95.42%. The P-CEUS pattern of SLNs was divided into six types. The IV-CEUS sequence was divided into three types. The IV-CEUS mode was divided into four types. Among the 438 SLNs detected by P-CEUS, 105 (23.97%) were malignant and 333 (76.03%) were benign. Among the previously classified P-CEUS, P-CEUS, IV-CEUS and combined contrast-enhanced ultrasound, the latter had the highest diagnostic efficacy (P<0.05), with sensitivity, specificity, positive predictive value, negative predictive value, accuracy and area under curve (AUC) of 81.90% (86/105), 97.30% (324/333), 90.53% (86/95), 94.46% (324/343), 93.61% (410/438) and 0.896 (0.864-0.923), respectively. Conclusions: The new classification of the P-CEUS and IV-CEUS features of SLNs was performed based on structural characteristics of lymph nodes. Compared with the previously classified P-CEUS, the new classification method has higher diagnostic performance. The combination of new classified P-CEUS and IV-CEUS is helpful to further improve the diagnostic performance of SLNs.

15.
Zhonghua Yi Xue Za Zhi ; 93(29): 2271-4, 2013 Aug 06.
Artículo en Zh | MEDLINE | ID: mdl-24300143

RESUMEN

OBJECTIVE: To explore the outcomes of anticoagulation, systematic thrombolysis and catheter-directed thrombolysis (CDT) in the treatment of lower extremity acute deep venous thrombosis (DVT). METHODS: The clinical data of 152 patients with lower extremity acute DVT from January 2005 to December 2009 were analyzed retrospectively. They were divided into single anticoagulation group (A), systematic thrombolysis plus anticoagulation group (B) and CDT plus anticoagulation group (C).Follow-up studies were performed to inquire about patient symptoms, check the status of affected extremities and examine venous patency with venous ultrasonography or anterograde venous radiography. The incidence rate of post-thrombotic syndrome (PTS) was evaluated with the Villalta score while the quality of life with CIVIQ-2 questionnaire. And the post-discharge anticoagulation time and use of compression stockings were analyzed in each group. RESULTS: (1)The venous patency rate was 69.1%, 70.8%, 85.1% in groups A, B and C respectively. The differences was significant between groups A and C (P < 0.05). The differences was insignificant between groups C and B (P > 0.05). And the venous patency rate of group C was higher than that of group B. The difference was insignificant between groups A and B (P > 0.05).Such remodeling effects as venous valvular destruction and intravenous wall thickening were observed in PTS patients with venous ultrasonography and anterograde venous radiography. (2) The incidence of PTS was 56.8%, 54.2%, 38.3% in groups A, B and C. Compared with groups A and B, the difference was significant in group C (P < 0.05). The difference was insignificant between groups A and B (P > 0.05). (3) CIVIQ-2 score was 20.2 ± 14.4, 20.1 ± 12.5, 16.6 ± 11.0 in groups A, B and C. Compared with groups A and B, the difference was insignificant in group C (P > 0.05). And it was lower in group C than groups A and B. (4) The differences of average anticoagulant time and compression stocking use were insignificant in 3 groups (P > 0.05). CONCLUSION: Compared with anticoagulant and systematic thrombolysis, a combination of CDT and anticoagulation may reduce the risk for PTS, alleviate clinical symptoms and improve quality of life.


Asunto(s)
Cateterismo Periférico/métodos , Terapia Trombolítica/métodos , Trombosis de la Vena/tratamiento farmacológico , Enfermedad Aguda , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticoagulantes/administración & dosificación , Anticoagulantes/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
16.
Rev Sci Instrum ; 94(1): 015110, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36725570

RESUMEN

When the load and speed of rotating machinery change, the vibration signal of rolling bearing presents an obvious nonstationary characteristic. Stochastic resonance (SR) mainly is convenient to analyze the stationary feature of vibration signals with high signal-to-noise ratio. However, it is difficult for SR to extract the nonstationary feature of rolling bearings under strong noise background. For one thing, the frequency change of nonstationary signals makes the occurrence of SR very difficult. For another, the features of rolling bearings are large parameters and further prevent the SR method from performing well. Therefore, combined with order analysis (OA), adaptive frequency-shift SR is presented in this paper. To solve the problem of frequency change, OA is used to convert the nonstationary feature into stationary feature, which resamples the nonstationary signal in the time domain to stationary signal in the angular domain. To solve the other problem, the frequency-shift method based on Fourier transform is adopted to move the fault feature frequency to low frequency, and thus SR is more likely to occur under small parameter conditions. The simulated and experimental results indicate that not only the amplitude of fault feature but also the signal-to-noise ratio is significantly improved. These demonstrate that the fault features of rolling bearing in variable speed conditions are extracted successfully.

17.
ACS Appl Mater Interfaces ; 15(29): 35350-35357, 2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37433068

RESUMEN

Covalent organic frameworks (COFs) are polymer networks with a precise structure and permanent porosity, making them an attractive platform for the detection of volatile analytes due to their chemical stability and accessible active sites. In this study, based on electron-rich N,N,N',N'-tetrakis(4-aminophenyl)-1,4-benzenediamine moiety, two 2D COFs with different topological structures and stacking models were designed by the strategy of spatial effect. The conductivity of the AB-stacked COF-NUST-20 was an order of magnitude higher than that of the AA-stacked COF-NUST-30. With the protonation of the imine bond, both COFs exhibited a strong, rapid, and reversible visible color change in response to corrosive HCl vapor. In addition, the AB-stacked COF-NUST-20, which facilitates both interlayer and intralayer charge transfer, shows better sensing performance. These findings demonstrate the usefulness of all-aromatic 2D COFs as real-time responsive chemosensors and provide insight into the design of sensing materials with high sensitivity.

18.
Huan Jing Ke Xue ; 44(11): 6215-6225, 2023 Nov 08.
Artículo en Zh | MEDLINE | ID: mdl-37973104

RESUMEN

Chengde's transitional region from plateau to plain is located in the transition zone of agriculture and livestock and is extremely sensitive to climate change and human activities. This study used the net primary productivity(NPP) of vegetation as an evaluation index to quantify the degree impacts of climate change and human activities on vegetation change in the region. The Thornthwaite Memorial model was used to calculate the potential NPP, and the actual NPP was obtained based on MODIS NPP remote sensing images, using the difference between the actual and potential NPPs to express the amount of change in NPP owing to human activities. We used the slope trend and coefficient of variation method to analyze the trend and stability distribution of the actual NPP, potential NPP, and NPP influenced by human activities, and the correlation between actual NPP and annual precipitation and annual average temperature was analyzed using the correlation coefficient method. Finally, we quantified the impact of climate change and human activities on vegetation change in the region. The results showed that 99.87% of the vegetation in the region was improved and changed steadily, and the proportions of the areas showing positive correlation between actual NPP and annual precipitation and annual average temperature were 99.87% and 91.66%, respectively. The potential NPP showed an increasing trend from northwest to southeast, whereas the trend and stability of the potential NPP both showed an increasing trend from west to east. The area where climate change and human activities played a role in vegetation improvement accounted for 99.71%, and that affected by climate change accounted for 0.14%, with the proportion of human activities leading to vegetation degradation being 0.15%.


Asunto(s)
Cambio Climático , Ecosistema , Humanos , Modelos Teóricos , Actividades Humanas , Temperatura , China
19.
Quant Imaging Med Surg ; 13(7): 4392-4404, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37456279

RESUMEN

Background: To retrospectively investigate the application of contrast-enhanced ultrasound on sentinel lymph node (SLN-CEUS) for SLN evaluation and mapping in breast cancer patients. Methods: Patients diagnosed with breast cancer at the First Affiliated Hospital of Sun Yat-sen University from June 2019 to March 2021 were conveniently evaluated by SLN-CEUS. The results of SLN-CEUS and B mode-ultrasound (BUS) were collected and compared. For patients who only underwent SLN-CEUS, we conducted a 1:1 propensity score matching (PSM). The diagnostic parameters, including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), false negative rate (FNR), false positive rate (FPR), and proportion of undetermined diagnoses were compared between the SLN-CEUS and BUS cohorts. The identification rate and FNR of sentinel lymph node biopsy (SLNB) were also assessed. Results: There were 327 patients in each of the SLN-CEUS and BUS cohorts. Among the entire cohort, both NPV [90.2% (95% CI, 85.4-93.5%) vs. 83.5% (95% CI, 77.8-88.0%), P=0.048] and accuracy [80.7% (95% CI, 76.5-85.0%) vs. 73.7% (95% CI, 68.9-78.5%), P<0.001] of SLN-CEUS were significantly higher than those of BUS. In non-neoadjuvant treatment (NAT) patients, the NPV [94.7% (95% CI, 89.9-97.4%) vs. 85.5% (95% CI, 79.1-90.2%), P=0.007] and accuracy [87.6% (95% CI, 83.2-92.0%) vs. 76.0% (95% CI, 70.4-81.5%), P<0.001] of SLN-CEUS were significantly higher than those of BUS. In NAT patients, no difference in diagnostic efficacy was found. The proportion of undetermined diagnoses of SLN-CEUS was significantly lower than that of BUS (5.8% vs. 15.3%, P<0.001). The identification rate of SLN-CEUS in overall patients, non-NAT patients, and NAT patients was 94.2%, 96.3%, and 89.9%, respectively. The FNR of SLNB with the blue-dye tracer in combination with SLN-CEUS in overall patients, non-NAT patients, and NAT patients was 7.3%, 4.0%, and 12.5%, respectively. Conclusions: Compared to BUS, SLN-CEUS is a better technique for diagnosing SLNs in early breast cancer patients, showing superiority in multiple diagnostic parameters. However, the diagnostic value of SLN-CEUS in NAT patients is still undetermined. SLN-CEUS is a promising mapping method in SLNB, with a high identification rate and a low FNR when used in combination with a blue-dye tracer.

20.
Sci Adv ; 9(45): eadi9442, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37939175

RESUMEN

Photoelectrochemical (PEC) organic transformations occurring at anodes are a promising strategy for circumventing the sluggish kinetics of the oxygen evolution reaction. Here, we report a free radical-mediated reaction instead of direct hole transfer occurring at the solid/liquid interface for PEC oxidation of benzyl alcohol (BA) to benzaldehyde (BAD) with high selectivity. A bismuth vanadate (BiVO4) photoanode coated with a 2,2'-bipyridine-based covalent organic framework bearing single Ni sites (Ni-TpBpy) was developed to drive the transformation. Experimental studies reveal that the reaction at the Ni-TpBpy/BiVO4 photoanode followed first-order reaction kinetics, boosting the formation of surface-bound ·OH radicals, which suppressed further BAD oxidation and provided a nearly 100% selectivity and a rate of 80.63 µmol hour-1 for the BA-to-BAD conversion. Because alcohol-to-aldehyde conversions are involved in the valorizations of biomass and plastics, this work is expected to open distinct avenues for producing key intermediates of great value.

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