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1.
iScience ; 27(2): 108781, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38313053

RESUMEN

Tandem reactions involve multi-step processes conducted in one pot, offering a cost-effective, environmentally friendly, and efficient approach to chemical transformations with high atom economy. The catalytic systems employed in tandem reactions are crucial for achieving desirable activity, selectivity, and stability. Researchers worldwide have extensively explored catalytic processes driven by various energy fields, such as electrocatalysis, thermocatalysis, and photocatalysis, aiming to facilitate multiple reactions and bond transformations. Continuous advancements have been made in reaction conditions, catalyst design, and preparation methods. This review provides a comprehensive overview of recent progress in tandem reactions, specifically focusing on electro-, thermo-, and photocatalysis, and categorizes them into catalysts, reactors, and fields based on their applications. Furthermore, the review highlights the significance of rational design in nanomaterial catalysts and the integration of multiple energy sources, emphasizing their potential to enhance selectivity, performance, and the development of combined catalysis.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38294745

RESUMEN

Objective: This study aims to explore the predictive value of preoperative C-reactive protein (CRP) and other inflammatory biomarkers: platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) for postoperative complications (infection, diarrhea, etc.) in colorectal tumor patients. Methods: A cohort of 109 colorectal tumor patients who underwent surgical resection for colorectal cancer at the hospital from January 2021 to December 2022 were selected as the research subjects. Patients' postoperative complications were tracked, and they were split into the complication group and the non-complication group. All patients underwent preoperative biochemical tests. Serum levels of CRP, PLR, and NLR were compared between the two groups. The relationship between these markers and postoperative complications in colorectal tumor patients was analyzed. A Logistic regression model was established to analyze their impact on postoperative complications, and a Receiver Operating Characteristic (ROC) curve was drawn to assess predictive value. Results: Among the 109 colorectal tumor patients, 31 cases (28.44%) experienced postoperative complications. The complication group had larger tumor diameters and a higher proportion of open surgeries compared to the non-complication group (P < .05). Serum levels of CRP, PLR, and NLR were higher in the complication group compared to the non-complication group (P < .05). Correlation analysis showed that serum CRP, PLR, and NLR values were positively correlated with postoperative complications in colorectal tumor patients (r > 0, P < .05). The Logistic regression model revealed that high serum CRP levels (95%CI: 1.253-2.503), PLR (95%CI: 1.005-1.041), and NLR values (95%CI: 2.702-20.533) were risk factors for postoperative complications in colorectal tumor patients (OR>1, P < .05). The ROC curve demonstrated that serum CRP levels, PLR, and NLR values had certain predictive values for postoperative complications in colorectal tumor patients (AUC=0.811, 0.789, 0.870), the optimal predictive values were obtained when the cut-off values were set at 5.400 mg/L, 142.790, and 2.485, respectively and combined detection showed even higher predictive values (AUC=0.913). At 1 week post-surgery, the patient's CRP levels, PLR value, and NLR value were significantly lower than pre-surgery (P < .05). Conclusion: Preoperative serum CRP, PLR, and NLR values are closely related to postoperative complications in colorectal tumor patients, and they can be used to predict the risk of postoperative complications in colorectal tumor patients. Clinically, early prediction of postoperative complications in patients can be achieved by measuring the aforementioned indicators, allowing for the implementation of appropriate preventive measures such as detoxification and infection control to improve patient outcomes.

3.
Cell Mol Biol (Noisy-le-grand) ; 69(10): 244-247, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37953554

RESUMEN

Accumulating evidences have shown that Peptostreptococcus anaerobius (P.a) is abundantly enriched in the fetus of colorectal cancer (CRC) patients. P.a is reported able to invade colorectal tissues. This study intends to uncover the clinical significance of P.a in CRC. Mucosal tissues collected from CRC cases (n=109) and precancerous healthy ones (n=65) were subjected to the determination of the absolute copy number of P.a by droplet digital PCR. The positive rate of P.a in mucosal tissues of CRC and healthy ones was 79.8% (87/109), and 55.4% (36/65), respectively. The average absolute copy number of P.a in them was 2.3 copy/ng DNA, and 0.32 copy/ng DNA, respectively. The abundance of P.a in mucosal tissues of CRC, and age and TNM staging of CRC cases were correlated to its survival. The abundance of P.a in CRC cases was remarkably correlated to the relative level of SQLE. The abundance of P.a can be monitored to predict the prognosis of CRC.


Asunto(s)
Neoplasias Colorrectales , Humanos , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , Peptostreptococcus/genética , Biomarcadores , ADN , Biomarcadores de Tumor/genética
4.
Artículo en Inglés | MEDLINE | ID: mdl-36901150

RESUMEN

The Macau peninsula is close to the tropical ocean, with a high population density and a large number of high-rise buildings, which require a windy environment with good ventilation and heat dissipation. Based on residential samples and the degree of agglomeration, the high-rise residential area in Areia Preta was selected as the focus of this study. Meanwhile, summer typhoons pose serious safety risks to high-rise buildings. Therefore, it is necessary to study the connection between spatial form and the wind environment. First of all, this research is based on relevant concepts and the wind environment evaluation system of high-rise buildings and conducts research on high-rise residential areas in Areia Preta. PHOENICS software is used to simulate the prevailing monsoon in winter and summer, as well as a typhoon in an extreme wind environment, and summarize the wind environment's characteristics. Secondly, by comparing the parameter calculation and simulation results, the possible relationship between the causes of each wind field is studied. Finally, conclusions are drawn about the urban form and wind environment of the site, and corresponding control strategies are proposed to reduce the shielding effect between buildings and typhoon damage. It can be used as a theoretical basis and reference point for urban construction and high-rise building planning and layout.


Asunto(s)
Programas Informáticos , Viento , Macao , Simulación por Computador , Estaciones del Año
5.
Biosens Bioelectron ; 196: 113721, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34673482

RESUMEN

2-Aminopurine (2-AP), a fluorescent isomer of adenine, is a popular fluorescent tag for DNA-based biosensors. The fluorescence of 2-AP is highly dependent on its microenvironment, i.e., almost non-fluorescent and merely fluorescent in dsDNA and ssDNA, respectively, but can be greatly brightened as mononucleotide. In most 2-AP-based biosensors, DNA transformation from dsDNA to ssDNA was employed, while selective digestion of 2-AP-labeled DNA with nucleases represents an appealing approach for improving the biosensor sensitivity. However, some detailed fundamental information, such as the reason for nuclease digestion, the influence of the labeling site, neighboring bases, or the label number of 2-AP for final signal output, are still largely unknown, which greatly limits the utility of 2-AP-based biosensors. In this work, using both steady- and excited-state fluorescence (lifetime), we demonstrated that nuclease digestion resulted in almost full liberation of 2-AP mononucleotides, and was free from labeling site and neighboring bases. Furthermore, we also found that nuclease digestion could lead to multiplexed sensitivity from increasing number of 2-AP labelling, but was not achievable for the conventional biosensors without full liberation of 2-AP. Considering the popularity of 2-AP in biosensing and other related applications, the above obtained information in sensitivity boosting is fundamentally important for future design of 2-AP-based biosensors.


Asunto(s)
2-Aminopurina , Técnicas Biosensibles , ADN , Digestión , Espectrometría de Fluorescencia
6.
Talanta ; 210: 120651, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31987189

RESUMEN

MicroRNAs (miRNAs) are important biomarkers because their abnormal expressions or mutations can usually indicate the development of cancers or other diseases. However, their high family sequence homology and low abundance pose a major challenge for the analysis of miRNAs. In the present work, we developed a dual strand extension recycling signal amplification strategy for non-label detection of miRNA-155 with high sensitivity on the basis of DNA polymerase and the G-quadruplex/thioflavin T (ThT) complexes. The specific miRNA-155 target sequences could initiate two strand extension-based independent recycling cycles under the function of the DNA polymerase, resulting in the production of many active G-quadruplex segments. The dye of ThT further bound the G-quadruplexes to induce greatly enhanced fluorescence for ultra-sensitively detecting miRNA-155 sequences at the low concentration of 35 fM in the dynamic range from 0.1 pM to 100 pM. The proposed detection strategy used the completely unmodified and synthetic DNA as probes and could be performed in homogeneous solutions. This method with a high selectivity could also be used for diluted serum samples. The demonstration of our new method for miRNA detection thus offers it with high potentials for miRNA biomarker analyses with the purpose of clinical diagnostics and biomedical applications.


Asunto(s)
MicroARNs/sangre , MicroARNs/genética , Técnicas de Amplificación de Ácido Nucleico , Humanos
7.
ACS Appl Mater Interfaces ; 11(27): 24132-24139, 2019 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-31251572

RESUMEN

Highly repeatable fabrication of compact perovskite films is crucial for large-area perovskite cells (PSCs) in commercial applications. In this work, a vapor-assisted method with the combination of spin-coating and thermal evaporation is employed to fabricate the double-layer PbI2/PbIxBr(2-x) precursor. It is found that surface morphologies of perovskite films could be tailored through tuning the spin-coating speed (the first precursor layer) and chemical compositions (the second precursor layer). The continuous pinhole-free perovskite films are successfully fabricated by double-layer PbI2/PbBr2 precursors. The open-circuit voltages of all the corresponding cells exceed 1.00 V, showing an average value of 1.02 V. The high mean voltage and small variation reveals high repeatability of this method. This work provides a potential method to achieve large-area and high-efficiency PSCs.

8.
Nanoscale Res Lett ; 12(1): 160, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28253562

RESUMEN

Coaxial structures exhibit great potential for the application of high-efficiency solar cells due to the novel mechanism of radial charge separation. Here, we intensively investigate the nonuniform effect of carrier separation efficiency (CSE) and light absorption in perovskite-based type-II coaxial nanowire solar cells (ZnO/CH3NH3PbI3). Results show that the CSE rapidly decreases along the radial direction in the shell, and the value at the outer side becomes extremely low for the thick shell. Besides, the position of the main light absorption gradually moves to the outer side with the increase of the shell thickness. As a result, the external quantum efficiency shows a positional dependence with a maximal value close to the border of the nanowire. Eventually, in our case, it is found that the maximal power conversion efficiency of the solar cells reduces from 19.5 to 17.9% under the effect of the nonuniformity of CSE and light absorption. This work provides a basis for the design of high-efficiency solar cells, especially type-II nanowire solar cells.

9.
Sci Rep ; 6: 29170, 2016 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-27403716

RESUMEN

Nanostructures decorated with noble metal nanoparticles (NPs) exhibit potential for use in highly sensitive optoelectronic devices through the localized surface plasmon resonance (LSPR) effect. In this study, Faraday rotation was significantly enhanced through the structural optimization of ferromagnetic (FM)/semiconductor composite nanostructures. Experimental and theoretical results revealed that the position of noble metal NPs significantly influenced the coupling of the LSPR-enhanced electromagnetic field with FM materials. Furthermore, nanostructures embedded with noble metals demonstrated an improved capability to efficiently use the electromagnetic field compared to other structures. The Faraday rotation of ZnO/Ag(NPs)/Fe was enhanced 58 fold compared to that of the ZnO(film)/Fe. This work provides a basis for the design of nanoarchitectures for miniaturized high-performance magneto-optical devices.

10.
Nanoscale Res Lett ; 10: 181, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25977654

RESUMEN

ZnO/Zn x Cd1-x Se coaxial nanowires (NWs) have been successfully synthesized by combining chemical vapor deposition with a facile alternant physical deposition method. The shell composition x can be precisely tuned in the whole region (0 ≤ x ≤ 1) by adjusting growth time ratio of ZnSe to CdSe. As a result, the effective bandgaps of coaxial nanowires were conveniently modified from 1.85 eV to 2.58 eV, almost covering the entire visible spectrum. It was also found that annealing treatment was in favor of forming the mixed crystal and improving crystal quality. An optimal temperature of 350°C was obtained according to our experimental results. Additionally, time resolved photo-luminescence spectra revealed the longest carrier lifetime in ZnO/CdSe coaxial nanowires. As a result, the ZnO/CdSe nanowire cell acquired the maximal conversion efficiency of 2.01%. This work shall pave a way towards facile synthesis of ternary alloys for photovoltaic applications.

11.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 33(7): 948-52, 2013 Jul.
Artículo en Chino | MEDLINE | ID: mdl-24063219

RESUMEN

OBJECTIVE: To explore the effect of Changji'an Capsule (CA) on mRNA expressions of neuropeptide Y (NPY) in the hypothalamus and colon and serum levels of adreno-cortico-tropic hormone (ACTH) in rats of diarrhea predominant irritable bowel syndrome (IBS-D) model rats. METHODS: Totally 48 SD rats were randomly divided into six groups, i.e., the normal control group, the model group, the Pinaverium Bromide group (PB, 0.018 g/kg), the high dose CA group (2.812 g/kg), the medium dose CA group (1.406 g/kg), and the low dose CA group (0.703 g/kg), 8 in each group. The IBS-D rat model was established by using separation of breast milk + stimulation of acetic acid + constraint of four limbs. Normal saline was given to rats in the normal control group and the model group. All medication lasted for 14 successive days by gastrogavage. The serum content of ACTH was detected by enzyme linked immunosorbent assay (ELISA). The expressions of NPY mRNA in the colon and the hypothalamus were detected using real-time fluorescence quantitative PCR. RESULTS: Compared with the normal control group, the serum ACTH content significantly increased (P < 0.01), the NPY mRNA expression in the colon and the hypothalamus obviously decreased (P < 0.01) in the model control group. Compared with the model group, the serum ACTH obviously decreased in the high dose CA group, the medium dose CA group, and the PB group (P < 0.01, P < 0.05). The NPY mRNA expression in the colon and the hypothalamus were obviously up-regulated in the high dose CA group, the medium dose CA group, the low dose CA group, and the PB group (P < 0.05). CONCLUSIONS: CA could modulate the abnormity of brain-gut axis of IBS-D rats possibly by up-regulating NPY mRNA expressions in the hypothalamus and the colon and down-regulating the ACTH content in the hypothalamic-pituitary-adrenal axis.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Síndrome del Colon Irritable/metabolismo , Neuropéptido Y/metabolismo , Hormona Adrenocorticotrópica/sangre , Animales , Colon/metabolismo , Modelos Animales de Enfermedad , Femenino , Hipotálamo/metabolismo , Masculino , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley
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