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1.
Nano Lett ; 24(28): 8502-8509, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38949570

RESUMEN

N2O is a dominant atmosphere pollutant, causing ozone depletion and global warming. Currently, electrochemical reduction of N2O has gained increasing attention to remove N2O, but its product is worthless N2. Here, we propose a direct eight-electron (8e) pathway to electrochemically convert N2O into NH3. As a proof of concept, using density functional theory calculation, an Fe2 double-atom catalyst (DAC) anchored by N-doped porous graphene (Fe2@NG) was screened out to be the most active and selective catalyst for N2O electroreduction toward NH3 via the novel 8e pathway, which benefits from the unique bent N2O adsorption configuration. Guided by theoretical prediction, Fe2@NG DAC was fabricated experimentally, and it can achieve a high N2O-to-NH3 Faradaic efficiency of 77.8% with a large NH3 yield rate of 2.9 mg h-1 cm-2 at -0.6 V vs RHE in a neutral electrolyte. Our study offers a feasible strategy to synthesize NH3 from pollutant N2O with simultaneous N2O removal.

2.
Anal Chem ; 96(3): 1054-1063, 2024 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-38190445

RESUMEN

In this work, an integrated strategy with excellent accuracy and high throughput is proposed for the precise indication of single nucleotide polymorphism (SNP) in nonsmall cell lung cancer diseases. Two types of point mutations (L858R and T790M) and the corresponding wild types could be identified together in a single high-performance liquid chromatographic run. Signal amplification was achieved through a series of enzyme ligation, primer extension, and enzyme cleavage strategies, and a large number of DNA probes with different fluorescence signals were finally generated. The factors affecting the spatiotemporal separation efficiency of four DNA probes were systematically investigated. The limits of detection of wild types (WTs) or mutant types (MTs) abbreviated as L858R-MT, L858R-WT, T790M-MT, and T790M-WT were 26, 24, 19, and 22 aM, respectively. In addition, the levels of mutant types and wild types in the serum of 40 nonsmall cell lung cancer patients at different stages were detected using the method, and the correlation between the mutation ratios and cancer stages was preliminarily verified. The proposed highly selective and sensitive method may serve as an alternative approach for early diagnosis and staging of nonsmall cell lung cancer.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Receptores ErbB/metabolismo , Polimorfismo de Nucleótido Simple , Mutación , Inhibidores de Proteínas Quinasas , Cromatografía Liquida , Sondas de ADN
3.
Anal Chem ; 96(13): 5195-5204, 2024 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-38520334

RESUMEN

The detection of multiple single nucleotide polymorphisms (SNPs) of circulating tumor DNA (ctDNA) is still a great challenge. In this study, we designed enzyme-assisted nucleic acid strand displacement amplification combined with high-performance liquid chromatography (HPLC) for the simultaneous detection of three ctDNA SNPs. First, the trace ctDNA could be hybridized to the specially designed template strand, which initiated the strand displacement nucleic acid amplification process under the synergistic action of DNA polymerase and restriction endonuclease. Then, the targets would be replaced with G-quadruplex fluorescent probes with different tail lengths. Finally, the HPLC-fluorescence assay enabled the separation and quantification of multiple signals. Notably, this method can simultaneously detect both the wild type (WT) and mutant type (MT) of multiple ctDNA SNPs. Within a linear range of 0.1 fM-0.1 nM, the detection limits of BRAF V600E-WT, EGFR T790M-WT, and KRAS 134A-WT and BRAF V600E-MT, EGFR T790M-MT, and KRAS 134A-MT were 29, 31, and 11 aM and 22, 29, and 33 aM, respectively. By using this method, the mutation rates of multiple ctDNA SNPs in blood samples from patients with lung or breast cancer can be obtained in a simple way, providing a convenient and highly sensitive analytical assay for the early screening and monitoring of lung cancer.


Asunto(s)
ADN Tumoral Circulante , Neoplasias Pulmonares , Humanos , ADN Tumoral Circulante/genética , Mutación , Polimorfismo de Nucleótido Simple , Proteínas Proto-Oncogénicas B-raf/genética , Receptores ErbB/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Inhibidores de Proteínas Quinasas , Cromatografía Liquida
4.
PLoS One ; 19(8): e0307946, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39137190

RESUMEN

Physical capital stock is the basic indicator of macroeconomic empirical studies and also an important manifestation of macroeconomic activity capacity. When measuring China's provincial physical capital stock by the perpetual inventory method, the treatment for the depreciation rate and the initial physical capital stock in the existing literature has some defects in reflecting the economic performance. The purpose of this paper is to build the most reliable and reasonable statistical series of China's provincial physical capital stock. We establish a measurement formula in form of the variable depreciation rate and improve the treatment for the depreciation rate and the initial physical capital stock. For the depreciation rate, we measure the benchmark depreciation rate of physical capital and determine the variable depreciation rate according to the economic growth rate, which makes the variable depreciation rate reflect the economic growth. For the initial physical capital stock, we measure the initial physical capital stock according to the capital output ratio, which makes the initial physical capital stock reflect the economic aggregate. Based on these improvements, we measure China's provincial physical capital stock from 1952 to 2022 by the perpetual inventory method. Through analyzing the measurement results, we have a more distinct insight into the temporal and spatial characteristics of China's provincial physical capital stock: The growth rate of physical capital stock at the provincial level has slowed in spite of remaining high; The eastern region is much higher than the central and western regions. According to these two characteristics, it is suggested that policymakers need to improve market mechanisms and adjust investment policies to promote a benign profile of economic growth and a regional optimization of capital formation.


Asunto(s)
Desarrollo Económico , China , Humanos , Modelos Económicos , Inversiones en Salud/economía
5.
Chem Commun (Camb) ; 60(37): 4918-4921, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38628069

RESUMEN

To avoid the unexpected aggregation and reduce the cytotoxicity of nanomaterials as optical probes in cell imaging applications, we propose a programmed DNA-cube as a carrier for silver nanoparticles (Ag NPs) to construct a specific hydrogen sulfide (H2S) responsive platform (Ag NP@DNA-cube) for diagnosing colorectal cancer (CRC) in this study. The DNA-cube maintains good dispersion of Ag NPs while providing excellent biocompatibility. Based on the characteristic overexpression of endogenous H2S in CRC cells, the Ag NPs are etched by H2S within target cells into silver sulfide quantum dots, thereby selectively illuminating the target cells. The Ag NP@DNA-cube exhibits a specific fluorescence response to CRC cells and achieves satisfactory imaging.


Asunto(s)
Neoplasias Colorrectales , ADN , Sulfuro de Hidrógeno , Nanopartículas del Metal , Plata , Sulfuro de Hidrógeno/análisis , Sulfuro de Hidrógeno/química , Humanos , Nanopartículas del Metal/química , Neoplasias Colorrectales/patología , Plata/química , ADN/química , Imagen Óptica , Puntos Cuánticos/química , Línea Celular Tumoral
6.
Heliyon ; 10(15): e35716, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39170323

RESUMEN

Purpose: Capillary Refill Time (CRT) measurement has gained increasing attention in the field of sepsis and septic shock. Recognizing pressure as a fundamental determinant in CRT measurement is crucial for establishing a standardized CRT measurement procedure. In this preliminary study, we elucidated the optimal pressing strength for CRT measurement by analyzing the CRTs measured under varying pressures. Method: Seventeen healthy individuals were enlisted to undergo CRT tests on their fingertips at various pressure levels. The applied force was initiated at 0.5N and incrementally increased by 0.5N until it reached 10.5N. An integrated Photoplethysmography (PPG) device was employed to capture fluctuations in light intensity. The CRT was automatically derived from the PPG signals via a specialized algorithm. The study included correlation assessment and reliability evaluation. Box plot and Bland-Altman plot were used to visualize the impact of pressure levels on CRTs. Results: A dataset of 1414 CRTs across 21 pressures showed significant differences (Kruskal-Wallis test, p < 0.0001), highlighting the impact of pressure on CRT. CRT values between 4.5N and 10.5N pressures varied less, with an Intraclass Correlation Coefficient (ICC) of 0.499 indicating moderate consistency. Notably, CRTs at 10N and 10.5N pressures revealed a high ICC of 0.790, suggesting strong agreement. Conclusion: A pressure range of 4.5N-10.5N is recommended for stable CRT measurements, with 10.0N-10.5N providing optimal consistency and reliability.

7.
Endocrine ; 84(3): 1064-1071, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38172344

RESUMEN

OBJECTIVE: This study utilized the stimulated thyroglobulin (sTg) to thyroid stimulating hormone (TSH) ratio to predict the long-term efficacy of 131I therapy in patients with moderate-to-high-risk differentiated thyroid cancer (DTC). METHODS: This study retrospectively analyzed 960 DTC patients with a median follow-up time of 30 months (6-92 months). The median age was 44 years. All patients underwent total thyroidectomy, lymph node dissection, and at least one 131I therapy. Patients were subjected to a final efficacy evaluation according to American Thyroid Association's 2015 guidelines. Patients were grouped according to their TSH levels before the initial 131I therapy and the final efficacy evaluation, and factors influencing TSH levels and final efficacy were analyzed. Construction of nomograms using independent risk factors affecting long-term outcomes. The cut-offs of sTg and sTg/TSH ratios were calculated for different long-term outcomes. Progression-free survival (PFS) of patients was analyzed by making Kaplan-Meier survival according to the cut-offs of sTg and sTg/TSH ratio. RESULTS: TSH (mU/L) levels were more concentrated at 60-90 in females (71.5%) and 30-60 in males (39.0%), while patients with younger age, more lymph node metastases, shorter time interval between surgery and the first 131I therapy, and lower dose of levothyroxine sodium taken prior to the first 131I therapy would have higher TSH levels (All P < 0.05).Patients who are male, have primary tumor involvement of the strap muscles, lymph node metastasis, distant metastasis, and higher sTg and sTg/TSH are more likely to have poor long-term outcomes (All P < 0.05).The cut-offs of sTg and sTg/TSH for long-term efficacy were 7.515 and 0.095. STg, sTg/TSH, tumor size, lymph node metastasis, and distant metastasis were shown to be independent risk factors for long-term efficacy. The mean PFSs were longer for patients who had sTg/TSH ≤ 0.095 and/or sTg≤7.515 ug/L. CONCLUSIONS: For patients with moderate-to-high-risk DTC, when sTg>7.515 ug/L and/or sTg/TSH > 0.095 before the first 131I therapy, patients are more likely to have a poor long-term efficacy after full 131I therapy. This means that this group of patients may require further surgical treatment or targeted drug therapy after 131I therapy.


Asunto(s)
Radioisótopos de Yodo , Tiroglobulina , Neoplasias de la Tiroides , Tiroidectomía , Tirotropina , Humanos , Femenino , Masculino , Neoplasias de la Tiroides/sangre , Neoplasias de la Tiroides/radioterapia , Neoplasias de la Tiroides/cirugía , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/terapia , Estudios Retrospectivos , Radioisótopos de Yodo/uso terapéutico , Adulto , Persona de Mediana Edad , Tirotropina/sangre , Tiroglobulina/sangre , Resultado del Tratamiento , Anciano , Adulto Joven , Adolescente
8.
Metabolism ; 156: 155934, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38762141

RESUMEN

BACKGROUND AND AIM: Clinically, septic males tend to have higher mortality rates, but it is unclear if this is due to sex differences in cardiac dysfunction, possibly influenced by hormonal variations. Cardiac dysfunction significantly contributes to sepsis-related mortality, primarily influenced by metabolic imbalances. Peroxisome proliferator-activated receptor delta (PPARδ) is a key player in cardiac metabolism and its activation has been demonstrated to favor sepsis outcomes. While estradiol (E2) is abundant and beneficial in females, its impact on PPARδ-mediated metabolism in the heart with regards to sex during sepsis remains unknown. METHODS AND RESULTS: Here, we unveil that while sepsis diminishes PPARδ nuclear translocation and induces metabolic dysregulation, oxidative stress, apoptosis and dysfunction in the heart thereby enhancing mortality, these effects are notably more pronounced in males than females. Mechanistic experiments employing ovariectomized(OVX) mice, E2 administration, and G protein-coupled estrogen receptor 1(GPER-1) knockout (KO) mice revealed that under lipopolysaccharide (LPS)-induced sepsis, E2 acting via GPER-1 enhances cardiac electrical activity and function, promotes PPARδ nuclear translocation, and subsequently ameliorates cardiac metabolism while mitigating oxidative stress and apoptosis in females. Furthermore, PPARδ specific activation using GW501516 in female GPER-1-/- mice reduced oxidative stress, ultimately decreasing NLRP3 expression in the heart. Remarkably, targeted GPER-1 activation using G1 in males mirrors these benefits, improving cardiac electrical activity and function, and ultimately enhancing survival rates during LPS challenge. By employing NLRP3 KO mice, we demonstrated that the targeted GPER-1 activation mitigated injury, enhanced metabolism, and reduced apoptosis in the heart of male mice via the downregulation of NLRP3. CONCLUSION: Our findings collectively illuminate the sex-specific cardiac mechanisms influencing sepsis mortality, offering insights into physiological and pathological dimensions. From a pharmacological standpoint, this study introduces specific GPER-1 activation as a promising therapeutic intervention for males under septic conditions. These discoveries advance our understanding of the sex differences in sepsis-induced cardiac dysfunction and also present a novel avenue for targeted interventions with potential translational impact.


Asunto(s)
Estradiol , Proteína con Dominio Pirina 3 de la Familia NLR , Sepsis , Transducción de Señal , Animales , Femenino , Masculino , Ratones , Estradiol/farmacología , Estradiol/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Miocardio/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Estrés Oxidativo , PPAR delta/metabolismo , Receptores de Estrógenos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Sepsis/metabolismo , Sepsis/complicaciones , Caracteres Sexuales
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