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1.
Crit Care Med ; 52(6): e314-e322, 2024 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-38363176

RESUMEN

OBJECTIVES: Persistent pulmonary hypertension of the newborn (PPHN) is a life-threatening disease. Despite being considered the gold standard treatment scheme, inhaled nitric oxide (iNO) is not readily available in settings with limited resources. Therefore, in recent years, research on related drugs is being actively pursued. Herein, we aimed to use random-effects network meta-analysis to evaluate the efficacy and associated mortality of different PPHN therapies. DATA SOURCES: We electronically searched the PubMed, Embase, and Cochrane Library for data up to January 27, 2023. STUDY SELECTION: Randomized controlled trials involving neonates with PPHN assessing efficacy and mortality of various treatments. DATA EXTRACTION: Details of study population, treatments, and outcomes were extracted. DATA SYNTHESIS: Direct pairwise comparisons and a network meta-analysis was performed under random effects. The ranking probability was further assessed based on the surface under the cumulative ranking curve (SUCRA). We analyzed 23 randomized clinical trials involving 902 newborns with PPHN. Sixteen different treatment strategies were compared with each other and conventional therapy (CON). A median concentration of 10-20 parts per million (ppm) iNO (MNO) coupled with sildenafil orally administered at a dose of 1-3 mg/kg/dose every 6-8 hours (OSID) demonstrated the best efficacy (MNO + OSID vs. CON: odds ratio [OR] = 27.53, 95% CI, 2.36-321.75; SUCRA = 0.818, ranking first; moderate quality). OSID combined with milrinone administered IV also performed well in terms of efficacy (OSID + milrinone vs. CON: OR = 25.13, 95% CI = 1.67-377.78; SUCRA = 0.811, ranking second; low quality) and mortality reduction (CON vs. OSID + milrinone: OR = 25.13, 95% CI = 1.67-377.78; SUCRA = 0.786, ranking last; low quality). CONCLUSIONS: MNO + OSID is the most effective PPHN treatment. If iNO is not available, OSID + milrinone is preferred.


Asunto(s)
Metaanálisis en Red , Óxido Nítrico , Síndrome de Circulación Fetal Persistente , Citrato de Sildenafil , Humanos , Recién Nacido , Síndrome de Circulación Fetal Persistente/tratamiento farmacológico , Síndrome de Circulación Fetal Persistente/terapia , Óxido Nítrico/uso terapéutico , Óxido Nítrico/administración & dosificación , Citrato de Sildenafil/uso terapéutico , Citrato de Sildenafil/administración & dosificación , Administración por Inhalación , Vasodilatadores/uso terapéutico , Vasodilatadores/administración & dosificación , Milrinona/uso terapéutico , Milrinona/administración & dosificación , Ensayos Clínicos Controlados Aleatorios como Asunto
2.
Bioorg Med Chem Lett ; 97: 129563, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-38008336

RESUMEN

Biothiols play a crucial role in maintaining redox balance in organisms, and anomalous levels of biothiols in human organs can lead to various sicknesses and biological disorders. This work developed a novel sensitive fluorescent probe TZ-NBD with double channels for highly efficient recognition of biothiols. TZ-NBD adopts 4-Chloro-7-nitrobenzofurazan (NBD-Cl) as the recognition moiety with simultaneous fluorescence output. By incorporating NBD-Cl with the other fluorophore, benzothiazole dihydrocyclopentachromene derivative (TZ-OH), the dual-channel sensitive fluorescence probe TZ-NBD was built. The existence of Cys/ Hcy could significantly trigger both the green and red fluorescent emissions, which were derived from fluorophores amine-substituted NBD and TZ-OH, respectively. While exposing to GSH, only the red-channel fluorescence signal could be detected, indicating the release of TZ-OH. The phenomena was mainly attributed to the fact that sulfur-substituted NBD has nearly no fluorescence, while amine-substituted NBD shows obvious green fluorescence. In our study, TZ-NBD exhibited dual-channel sensitivity, fast response, and excellent selectivity to biothiols in vitro. Moreover, TZ-NBD was favorably utilized for recognition of biothiols in vivo. We believe that the sensitive fluorescence probe with double channels can afford an alternate approach for monitoring biothiols in organisms and would be useful for studying diseases associated with biothiols.


Asunto(s)
Cisteína , Colorantes Fluorescentes , Humanos , Glutatión , Espectrometría de Fluorescencia , Aminas , Homocisteína
3.
Infection ; 52(5): 2071-2082, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38904890

RESUMEN

PURPOSE: C-reactive protein (CRP), as an acute phase protein, is a sensitive indicator of neonatal bacterial infection. Some recent studies have shown that there is a correlation between CRP levels in serum and saliva, and using saliva to detect CRP levels is expected to be an ideal and non-invasive method to predict neonatal infection. The purpose of this Meta-analysis was to evaluate the diagnostic value of salivary CRP for neonatal infection. METHODS: We searched PubMed, Embase, Web of Science, and Scopus databases in October 2023 and included observational studies that examined salivary CRP in newborns with bacterial infections. Data was extracted regarding the methodology, participant characteristics, and outcome measures. RESULTS: Nine articles were included, with a total of 696 newborns. Salivary CRP levels are significantly higher in neonates with infections compared to non-infected group (SMD = 0.58, 95%CI [0.40-0.76], P < 0.001). The accuracy for salivary CRP to predict serum CRP abnormality is high (sensitivity 86%, specificity 88%, area under the curve = 0.94). CONCLUSIONS: Our meta-analysis suggested that salivary CRP can be used as an alternative biomarker to serum CRP for detecting neonatal infection.


Asunto(s)
Biomarcadores , Proteína C-Reactiva , Saliva , Humanos , Proteína C-Reactiva/análisis , Saliva/química , Recién Nacido , Biomarcadores/análisis , Biomarcadores/sangre , Infecciones Bacterianas/diagnóstico , Sensibilidad y Especificidad , Enfermedades del Recién Nacido/diagnóstico
4.
Environ Res ; 262(Pt 2): 119973, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39260723

RESUMEN

Enzymatic hydrolysis has been considered as an eco-friendly pretreatment method for enhancing bioconversion process of food waste (FW). However, existing commercial enzymes and microbial monomer-based compound enzymes (MME) have the issues of uneven distribution of enzymatic activity and low matching degree with the components of FW, leading to low efficiency with enzymatic hydrolysis and removal of antibiotic resistance genes (ARGs). This study used FW as the substrate, under the co-culture system, produced a microbial consortium-based compound enzymes (MCE) with oriented and well-matching degree for FW hydrolysis and ARGs removal, of which the performance, metabolic pathways and microbial communities were also investigated in depth. Results showed that the best performance for ARGs was achieved by the MCE prepared by mixing 1:5 of Aspergillus oryzae and Aspergillus niger after 12 days fermentation. The highest soluble chemical oxygen demand (SCOD) concentration and ARGs removal could respectively reach 83.90 ± 1.67 g/L and 45.95% after MCE pretreatment. The analysis of metabolic pathways revealed that 1:5 MCE pretreatment strengthened the catalytic activity of carbohydrate-active enzymes, increased the abundances of genes involved in cellulose and starch degradation, polysaccharide synthesis, ATP binding cassette (ABC) transporters and global regulation, while decreased the abundances of genes involved in mating pair formation system, two-component regulatory systems and quorum sensing, thereby enhanced FW hydrolysis and restrained ARGs dissemination. Microbial community analysis further indicated that the 1:5 MCE pretreatment promoted growth, metabolism and richness of functional microbes, while inhibited the host microbes of ARGs. It is expected that this study can provide useful insights into understanding the fate of ARGs in food waste during MCE pretreatment process.

5.
Environ Res ; 255: 119125, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38740293

RESUMEN

With the drastic growth of the economic and population, the global energy requirement is on the rise, and massive human and material resources have been put into the development of alternative and renewable energy sources. Biodiesel has been recognized as a green and sustainable alternative energy, but the raw materials-associated source and cost makes it difficult to achieve large-scale commercial production. Microbial lipids (ML) produced by oleaginous microbes have attracted more and more topics as feedstocks for biodiesel production because of their unique advantages (fast growth cycle, small footprint and so on). However, there are still many problems and challenges ahead towards commercialization of ML-based biodiesel, especially the cost of feedstock for ML production. Food waste (FW) rich in organic matters and nutrients is an excellent and almost zero-cost feedstock for ML production. However, current biological routes of FW-based ML production have some defects, which make it impossible to achieve full industrialization at present. Therefore, this review intends to provide a critical and comprehensive analysis of current biological routes of FW-based ML production with the focus on the challenges and solutions forward. The biological routes towards future FW-based ML production must be able to concurrently achieve economic feasibility and environmental sustainability. On this condition, an innovative integrated biological route for FW-based ML production has thus been put forward, which is also elucidated on its economic and environmental sustainability. Moreover, the prospective advantages, limitations and challenges for future scale-up of FW-based ML production have also been outlined, together with the perspectives and directions forward.


Asunto(s)
Biocombustibles , Biocombustibles/economía , Lípidos , Alimento Perdido y Desperdiciado
6.
Mol Divers ; 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38687400

RESUMEN

In this paper, a series of novel 1,2,4-trizaole-substituted 1,3,4-oxadiazole derivatives with a dual thioether moiety were constructed. The synthetic compounds were characterized by 1H NMR, 13C NMR, HRMS, and single crystal diffraction. The antimicrobial activities of title compounds against fungi (Pyricutaria oryzae Cav., Phomopsis sp., Botryosphaeria dothidea, cucumber Botrytis cinerea, tobacco Botrytis cinerea, blueberry Botrytis cinerea) and bacteria (Xanthomonas oryzae pv. oryzicola, Xoc; Xanthomonas axonopodis pv. citri, Xac) revealed these compounds possessed excellent antibacterial activity through mycelial growth rate method and turbidity method, respectively. Among them, compounds 7a, 7d, 7g, 7k, 7l, and 7n had the antibacterial inhibition rate of 90.68, 97.86, 93.61, 97.70, 97.26, and 92.34%, respectively. The EC50 values of 7a, 7d, 7g, 7k, 7l, and 7n were 58.31, 48.76, 58.50, 40.11, 38.15, and 46.99 µg/mL, separately, superior to that of positive control pesticide thiodiazole copper (104.26 µg/mL). The molecular docking simulation of compound 7l and glutathione s-transferase also confirmed its good activity. The in vivo bioassay toward Xac infected citrus leaves was also performed to evaluate the potential of compounds as efficient antibacterial reagent. Further study of antibacterial mechanism was also carried out, including extracellular polysaccharide production, permeability of bacterial membrane, and scanning electron microscope observations. The excellent antibacterial activities of these compounds provided a strong support for its application for preventing and control plant diseases.

7.
J Environ Manage ; 365: 121614, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38943750

RESUMEN

Low methane production and long retention time are the main dilemmas in current anaerobic digestion (AD) of waste activated sludge (WAS). This work used WAS as only substrate to prepare oriented multi-enzyme (ME) that directly used for WAS pretreatment. Under the optimal parameters, the highest activities of protease and amylase in ME could respectively reach 16.5 U/g and 580 U/g, and the corresponding methane production attained 197 mLCH4/g VS, which was increased by 70.4% compared to blank group. It was found that ME pretreatment could strengthen WAS disintegration and organic matters dissolution, lead to the soluble chemical oxygen demand (SCOD) was increased from the initial 486 mg/L to 2583 mg/L, and the corresponding volatile suspended solid (VSS) and extracellular polymeric substances (EPS) were reduced by 27% and 73.8%, respectively. The results of three-dimensional excitation-emission matrix (3D-EEM) and Fourier transform infrared spectroscopy (FTIR) indicated that protein disintegration may be the critical step during the process of WAS hydrolysis with ME, of which the release of tyrosine-like proteins achieved the better biodegradability of WAS, while the results of X-ray photoelectron spectroscopy (XPS) showed that the formation of protein derivatives was the main harmful factor that could extend the lag phase of AD process. Microbial communities analysis further suggested that ME pretreatment facilitated the enrichment of acetogenic bacteria and acetotrophic methanogens, which caused the transition of the methanogenesis pathway from hydrogenotrophic to acetotrophic. This study is expected to furnish valuable insight for ME pretreatment on enhancing WAS disintegration and methane production.


Asunto(s)
Biodegradación Ambiental , Metano , Aguas del Alcantarillado , Anaerobiosis , Metano/metabolismo , Análisis de la Demanda Biológica de Oxígeno , Eliminación de Residuos Líquidos/métodos , Espectroscopía Infrarroja por Transformada de Fourier , Reactores Biológicos
8.
Angew Chem Int Ed Engl ; : e202415445, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39410669

RESUMEN

Converting greenhouse gases into valuable products has become a promising approach for achieving a carbon-neutral economy and sustainable development. However, the conversion efficiency depends on the energy yield of the substrate. In this study, we developed an electro-biocatalytic system by integrating electrochemical and microbial processes to upcycle CO2 into a valuable product (ectoine) using renewable energy. This system initiates the electrocatalytic reduction of CO2 to methane, an energy-dense molecule, which then serves as an electrofuel to energize the growth of an engineered methanotrophic cell factory for ectoine biosynthesis. The scalability of this system was demonstrated using an array of ten 25 cm2 electrochemical cells equipped with a high-performance carbon-supported isolated copper catalyst. The system consistently generated methane at the cathode under a total partial current of approximately -37 A (~175 mmolCH4 h-1) and O2 at the anode under a total partial current of approximately 62 A (~583 mmolO2 h-1). This output met the requirements of a 3-L bioreactor, even at maximum CH4 and O2 consumption, resulting in the high-yield conversion of CO2 to ectoine (1146.9 mg L-1). This work underscores the potential of electrifying the biosynthesis of valuable products from CO2, providing a sustainable avenue for biomanufacturing and energy storage.

9.
Anal Chem ; 95(48): 17577-17585, 2023 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-38050673

RESUMEN

Early detection and effective treatment of thyroid cancer are vital due to the aggressiveness and high mortality rate of the cancer. Nevertheless, the exploration of dipeptidyl peptidase-IV (DPP-IV) as a biomarker for thyroid diseases has not been widely conducted. In this study, we developed a novel non-π-conjugated near-infrared fluorescent probe, MB-DPP4, specifically designed to visualize and detect endogenous DPP-IV. Traditional DPP-IV-specific fluorescent probes rely primarily on the intramolecular charge transfer mechanism. For this reason, these probes are often hampered by high background levels that can inhibit their ability to achieve a fluorescence turn-on effect. MB-DPP4 successfully surmounts several drawbacks of traditional DPP-IV probes, boasting unique features such as exceptional selectivity, ultrahigh sensitivity (0.29 ng/mL), innovative structure, low background, and long-wavelength fluorescence. MB-DPP4 is an "off-on" chemosensor that exhibits strong fluorescence at 715 nm and releases a methylene blue (MB) fluorophore upon interacting with DPP-IV, resulting in a visible color change from colorless to blue. Given these remarkable attributes, MB-DPP4 shows great promise as a versatile tool for advancing research on biological processes and for evaluating the physiological roles of DPP-IV in living systems. Finally, we conducted a comprehensive investigation of DPP-IV expression in human serum, urine, thyroid cells, and mouse thyroid tumor models. Our findings could potentially establish a foundation for the early diagnosis and treatment of thyroid diseases.


Asunto(s)
Dipeptidil Peptidasa 4 , Neoplasias de la Tiroides , Animales , Ratones , Humanos , Dipeptidil Peptidasa 4/metabolismo , Colorantes Fluorescentes/química , Detección Precoz del Cáncer , Neoplasias de la Tiroides/diagnóstico por imagen
10.
Appl Environ Microbiol ; 89(1): e0188322, 2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36622175

RESUMEN

Methanotrophs play key roles in global methane cycling and are promising platforms for methane bioconversion. However, major gaps existing in fundamental knowledge undermines understanding of these methane-consuming microorganisms. To associate genes with a phenotype at the genome-wide level, we developed a Cre/lox-mediated method for constructing a large-scale CRISPRi library in a model methanotroph Methylotuvimicrobium buryatense 5GB1C. The efficiency of this Cre mediated integration method was up to a level of 105 CFU/µg DNA. Targeting 4,100 predicted protein-coding genes, our CRISPRi pooled screening uncovered 788 core genes for the growth of strain 5GB1C using methane. The core genes are highly consistent with the gene knockout results, indicating the reliability of the CRISPRi screen. Insights from the core genes include that annotated isozymes generally exist in metabolic pathways and many core genes are hypothetical genes. This work not only provides functional genomic data for both fundamental research and metabolic engineering of methanotrophs, but also offers a method for CRISPRi library construction. IMPORTANCE Due to their key role in methane cycling and their industrial potential, methanotrophs have drawn increasing attention. Genome-wide experimental approaches for gene-phenotype mapping accelerate our understanding and engineering of a bacterium. However, these approaches are still unavailable in methanotrophs. This work has two significant implications. First, the core genes identified here provide functional genetic basics for complete reconstruction of the metabolic network and afford more clues for knowledge gaps. Second, the Cre-mediated knock-in method developed in this work enables large-scale DNA library construction in methanotrophs; the CRISPRi library can be used to screen the genes associated with special culture conditions.


Asunto(s)
Metano , Reproducibilidad de los Resultados , Biblioteca de Genes , Metano/metabolismo
11.
Luminescence ; 38(2): 152-158, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36597958

RESUMEN

Over the past few years, ratiometric fluorescent nanoprobes have garnered substantial interest because of their self-calibration characteristics. This research developed a ratiometric fluorescent sensor to detect phosphate. Through encapsulating luminescent materials, gold nanoclusters (AuNCs) and carbon dots (CDs) into a zeolitic imidazolate framework-8 (ZIF-8), the fluorescence signal of AuNCs was enhanced, while that of CDs was suppressed. After phosphate was added, it could decompose ZIF-8, and AuNCs and CDs were released, which weakened the fluorescence signal of the AuNCs while restoring that of the CDs. Thereby, this makes CDs/AuNCs@ZIF-8 a potential fluorescent sensor for phosphate determination. The ratiometric sensor had facile synthesis, good selectivity, and a low detection limit. Therefore, this sensor was an effective tool for the detection of phosphate.


Asunto(s)
Nanopartículas del Metal , Puntos Cuánticos , Zeolitas , Colorantes Fluorescentes , Fosfatos , Cobre , Espectrometría de Fluorescencia , Carbono , Oro , Límite de Detección
12.
Molecules ; 28(18)2023 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-37764273

RESUMEN

To explore more efficient and less toxic antibacterial and antifungal pesticides, we utilized 2,6-difluorobenzamide as a starting material and ultimately synthesized 23 novel benzoylurea derivatives containing a pyrimidine moiety. Their structures were characterized and confirmed by 1H NMR, 13C NMR, 19F NMR, and HRMS. The bioassay results demonstrated that some of the title compounds exhibited moderate to good in vitro antifungal activities against Botrytis cinerea in cucumber, Botrytis cinerea in tobacco, Botrytis cinerea in blueberry, Phomopsis sp., and Rhizoctonia solani. Notably, compounds 4j and 4l displayed EC50 values of 6.72 and 5.21 µg/mL against Rhizoctonia solani, respectively, which were comparable to that of hymexazol (6.11 µg/mL). Meanwhile, at 200 and 100 concentrations, the target compounds 4a-4w exhibited lower in vitro antibacterial activities against Xanthomonas oryzae pv. oryzicola and Xanthomonas citri subsp. citri, respectively, compared to those of thiodiazole copper. Furthermore, the molecular docking simulation demonstrated that compound 4l formed hydrogen bonds with SER-17 and SER-39 of succinate dehydrogenase (SDH), providing a possible explanation for the mechanism of action between the target compounds and SDH. This study represents the first report on the antifungal and antibacterial activities of novel benzoylurea derivatives containing a pyrimidine moiety.


Asunto(s)
Antifúngicos , Fungicidas Industriales , Antifúngicos/farmacología , Antifúngicos/química , Simulación del Acoplamiento Molecular , Antibacterianos/farmacología , Antibacterianos/química , Pirimidinas/farmacología , Relación Estructura-Actividad , Fungicidas Industriales/farmacología , Fungicidas Industriales/química
13.
Appl Microbiol Biotechnol ; 106(8): 3191-3199, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35384448

RESUMEN

Methanotrophs capable of converting C1-based substrates play an important role in the global carbon cycle. As one of the essential macronutrient components in the medium, the uptake of nitrogen sources severely regulates the cell's metabolism. Although the feasibility of utilizing nitrogen gas (N2) by methanotrophs has been predicted, the mechanism remains unclear. Herein, the regulation of nitrogen fixation by an essential nitrogen-fixing regulator (NifA) was explored based on transcriptomic analyses of Methylomicrobium buryatense 5GB1. A deletion mutant of the nitrogen global regulator NifA was constructed, and the growth of M. buryatense 5GB1ΔnifA exhibited significant growth inhibition compared with wild-type strain after the depletion of nitrate source in the medium. Our transcriptome analyses elucidated that 22.0% of the genome was affected in expression by NifA in M. buryatense 5GB1. Besides genes associated with nitrogen assimilation such as nitrogenase structural genes, genes related to cofactor biosynthesis, electron transport, and post-transcriptional modification were significantly upregulated in the presence of NifA to enhance N2 fixation; other genes related to carbon metabolism, energy metabolism, membrane transport, and cell motility were strongly modulated by NifA to facilitate cell metabolisms. This study not only lays a comprehensive understanding of the physiological characteristics and nitrogen metabolism of methanotrophs, but also provides a potentially efficient strategy to achieve carbon and nitrogen co-utilization.Key points• N2 fixation ability of M. buryatense 5GB1 was demonstrated for the first time in experiments by regulating the supply of N2.• NifA positively regulates nif-related genes to facilitate the uptake of N2 in M. buryatense 5GB1.• NifA regulates a broad range of cellular functions beyond nif genes in M. buryatense 5GB1.


Asunto(s)
Fijación del Nitrógeno , Transcriptoma , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Carbono/metabolismo , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Genes Bacterianos , Methylococcaceae , Nitrógeno/metabolismo , Fijación del Nitrógeno/genética
14.
J Sep Sci ; 45(3): 697-705, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34817924

RESUMEN

In the present study, we propose a novel method for the extraction of parabens in personal care products. A new, simple adsorptive material was obtained by combining metal-organic frameworks and melamine sponges using the adhesive property of polyvinylidene fluoride. This new material, metal-organic frameworks/melamine sponges, was found to be particularly suitable for solid-phase extraction. The structural characteristics of metal-organic frameworks/melamine sponges were first analyzed by scanning electron microscopy. Subsequently, solid-phase extraction was performed on sample solutions, and the extracted substances were then analyzed by high-performance liquid chromatography. Following optimization of important experimental conditions, excellent recovery rates were obtained. Our novel method was then applied to the extraction of four parabens (methylparahydroxybenzoates, ethylparahydroxybenzoates, propylparahydroxybenzoates, and butylparahydroxybenzoates) from real samples. The results yielded limits of detection of 0.26-0.41 ng/mL. The inter- and intra-day recoveries were 104.0-109.7% and 91.2-98.1%, respectively (relative standard deviation, <13.8%).


Asunto(s)
Parabenos , Extracción en Fase Sólida , Cromatografía Líquida de Alta Presión/métodos , Parabenos/análisis , Extracción en Fase Sólida/métodos , Triazinas/análisis
15.
Anal Chem ; 93(10): 4434-4440, 2021 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-33660978

RESUMEN

Cross-linking mass spectrometry (XL-MS) has made significant progress in understanding the structure of protein and elucidating architectures of larger protein complexes. Current XL-MS applications are limited to targeting lysine, glutamic acid, aspartic acid, and cysteine residues. There remains a need for the development of novel cross-linkers enabling selective targeting of other amino acid residues in proteins. Here, a novel simple cross-linker, namely, [4,4'-(disulfanediylbis(ethane-2,1-diyl)) bis(1,2,4-triazolidine-3,5-dione)] (DBB), has been designed, synthesized, and characterized. This cross-linker can react selectively with tyrosine residues in protein through the electrochemical click reaction. The DBB cross-links produced the characteristic peptides before and after electrochemical reduction, thus permitting the simplified data analysis and accurate identification for the cross-linked products. This is the first time a cross-linker is developed for targeting tyrosine residues on protein without using photoirradiation or a metal catalyst. This strategy might potentially be used as a complementary tool for XL-MS to probe protein 3D structures, protein complexes, and protein-protein interaction.


Asunto(s)
Proteínas , Tirosina , Reactivos de Enlaces Cruzados , Espectrometría de Masas , Péptidos
16.
Mikrochim Acta ; 189(1): 13, 2021 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-34870756

RESUMEN

A H2O2-free colorimetric protocol based on urchin-like Au@Pt nanoparticles (Au@Pt NPs) has been developed for the sensitive and selective determination of cysteine (Cys). We verified the intrinsic oxidase-like activity of the Au@Pt NPs. They can act as artificial mimic oxidases to catalyse the oxidization of 3,3',5,5'-tetramethylbenzidine (TMB) with the assistance of dissolved oxygen, avoiding the use of H2O2 in the colorimetric determination of Cys. In addition, the discrimination of Cys from the other two biothiol analogues, homocysteine and glutathione, can be easily realized through a simple ageing process. HNO3 is added to this colorimetric system to terminate the reaction by oxidizing ox-TMB (oxidized form of TMB) to diphenoquinone (DPQ), thus generating a characteristic absorption peak of DPQ at 450 nm. By recording the absorbance at 450 nm, interference from the aggregated Au@Pt NPs (absorption peak at 670 nm) when 650 nm (the characteristic absorption peak of ox-TMB) is used as the absorption wavelength can be eliminated. We investigated this H2O2-free colorimetric protocol and obtained high sensitivity, with a detection limit of 1.5 nM and relatively high selectivity. The analytical performance for real samples was further explored. The Au@Pt NP-based H2O2-free colorimetric protocol is of great significance for the sensitive and selective determination of Cys in practical samples in different scenarios.

17.
Cancer Cell Int ; 20: 232, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32536820

RESUMEN

BACKGROUND: Dysregulation of long non-coding RNAs (lncRNAs) results in development of human diseases including hepatocellular carcinoma (HCC). Although several HCC related lncRNAs have been reported, the biological functions of many lncRNAs during the development of HCC remains unknown. METHODS: The expression of ST8SIA6-AS1 was studied by realtime PCR (RT-qPCR) and bioinformatic analysis. The biological functions of ST8SIA6-AS1 was examined by CCK-8 assay and flow cytometry analysis. The target of ST8SIA6-AS1 was analyzed by bioinformatic analysis and validated by dual luciferase reporter assay, western blotting and RT-qPCR. RESULTS: In this study we demonstrated that ST8SIA6-AS1 was an upregulated lncRNA in hepatocellular carcinoma. SiRNA-mediated knockdown of ST8SIA6-AS1 repressed cell proliferation and induced cell apoptosis in HCC cells. Bioinformatic analysis and RT-qPCR further showed that ST8SIA6-AS1 mainly located in cytoplasm. Dual luciferase reporter assay further revealed that ST8SIA6-AS1 interacted with miR-4656 in HCC cells. In addition, HDAC11 was identified as a target gene in HCC cells and ST8SIA6-AS1 could upregulate HDAC11 via sponging miR-4656. Transfection of recombinant HDAC11 partially rescued the inhibition of cell proliferation and increase of cell apoptosis inducing by knockdown of ST8SIA6-AS1. CONCLUSION: In conclusion, our findings suggested that ST8SIA6-AS1 was a novel upregulated lncRNA in HCC and could facilitate cell proliferation and resistance to cell apoptosis via sponging miR-4656 and elevation of HDAC11, which might be a promising biomarker for patients with HCC.

18.
Luminescence ; 35(8): 1231-1237, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32500652

RESUMEN

A fluorescent probe L-Cu2+ based on quinoline, coumarin and Cu2+ has been synthesized and characterized for hypochlorite determination. After copper ion was added to the solution of ligand L, the fluorescence quenching at 490 nm might result from a ligand-metal charge transfer (LMCT) process and its strong coordination ability for Cu2+ . In the presence of hypochlorite, the structure of ligand L was destroyed to form 7-(diethylamino)-coumarin-3-carboxylic acid, and the fluorescence was restored at 460 nm. In this case, L-Cu2+ complex could be used as a fluorescent probe to detect hypochlorite, with the advantages of rapid, selective, wide linear range and low detection limit.


Asunto(s)
Ácido Hipocloroso , Quinolinas , Cobre , Cumarinas , Colorantes Fluorescentes , Espectrometría de Fluorescencia , Agua
19.
Luminescence ; 35(7): 1036-1042, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32515169

RESUMEN

A highly sensitive and selective colorimetric analysis method based on unmodified gold nanoparticles (AuNPs) to detect iodide ions (I- ) in solution in the presence of hexadecyl trimethyl ammonium bromide (CTAB) and mercury ions (Hg2+ ) has been successfully developed. Hg2+ could form a gold amalgam with AuNPs to protect AuNPs from CTAB-induced aggregation caused by the electrostatic attraction between CTAB and citrate ion-covered AuNPs. When a mixture of Hg2+ and I- was added to the solution of AuNPs, the formation of the HgI2 complex destroyed the protection of Hg2+ for AuNPs, which led to the aggregation of AuNPs accompanied with the change in colour of the solution from red to grey black and decrease in the absorbance of AuNPs at 520 nm. There was a good linear relationship between A520nm and I- concentration from 0 to 800 nM with a low limit of detection (LOD) of 4.2 nM. Furthermore, this simple and reliable colorimetric sensor has been applied successfully to the detection of I- in practical samples.


Asunto(s)
Mercurio , Nanopartículas del Metal , Colorimetría , Oro , Yoduros , Iones
20.
Zhonghua Nan Ke Xue ; 26(2): 118-122, 2020 Feb.
Artículo en Zh | MEDLINE | ID: mdl-33346413

RESUMEN

OBJECTIVE: To study the correlation between the brain regional homogeneity (ReHo) features and the clinical characteristics of the patients with psychogenic erectile dysfunction (pED). METHODS: Using IIEF-5 and the Self-Esteem and Relationship (SEAR) questionnaire, we evaluated the erectile function and psychosocial status of 32 pED patients and 28 healthy male subjects. Then, we compared the regional brain activity between the patients and healthy controls by resting-state functional magnetic resonance imaging (RS-fMRI) and the ReHo method, analyzed the correlation of the ReHo value of the altered brain regions with the results of IIEF-5 and SEAR questionnaire investigation, and explored the relationship between the ReHo features and the symptoms of the pED patients. RESULTS: Compared with the healthy male subjects, the pED patients obtained significantly lower IIEF-5 scores (22.21 ± 0.98 vs 13.97 ± 3.60, P < 0.01) and SEAR scores (61.92 ± 3.73 vs 37.58 ± 7.96, P < 0.01), a higher ReHo value of the left lateral cerebellum, and a lower ReHo value of the right precentral gyrus. The ReHo value of the left lateral cerebellum was correlated negatively with the IIEF-5 scores (r= -0.51, P < 0.01) and SEAR scores (r = -0.54, P < 0.01), while that of the right precentral gyrus positively with the IIEF-5 scores (r = 0.57, P < 0.01) and SEAR scores (r = 0.66, P < 0.01). CONCLUSIONS: Patients with pED had lateral cerebellum-mediated abnormal sensory integration and precentral gyrus-related dysfunction of motor imagery and motor execution.


Asunto(s)
Encéfalo/diagnóstico por imagen , Disfunción Eréctil/psicología , Estudios de Casos y Controles , Cerebelo/diagnóstico por imagen , Lóbulo Frontal/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino
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