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1.
Nature ; 607(7918): 276-280, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35831597

RESUMEN

One of the main developments in unconventional superconductivity in the past two decades has been the discovery that most unconventional superconductors form phase diagrams that also contain other strongly correlated states. Many systems of interest are therefore close to more than one instability, and tuning between the resultant ordered phases is the subject of intense research1. In recent years, uniaxial pressure applied using piezoelectric-based devices has been shown to be a particularly versatile new method of tuning2,3, leading to experiments that have advanced our understanding of the fascinating unconventional superconductor Sr2RuO4 (refs. 4-9). Here we map out its phase diagram using high-precision measurements of the elastocaloric effect in what we believe to be the first such study including both the normal and the superconducting states. We observe a strong entropy quench on entering the superconducting state, in excellent agreement with a model calculation for pairing at the Van Hove point, and obtain a quantitative estimate of the entropy change associated with entry to a magnetic state that is observed in proximity to the superconductivity. The phase diagram is intriguing both for its similarity to those seen in other families of unconventional superconductors and for extra features unique, so far, to Sr2RuO4.

2.
Proc Natl Acad Sci U S A ; 119(18): e2200795119, 2022 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-35467986

RESUMEN

How larvae of the many phyla of marine invertebrates find places appropriate for settlement, metamorphosis, growth, and reproduction is an enduring question in marine science. Biofilm-induced metamorphosis has been observed in marine invertebrate larvae from nearly every major marine phylum. Despite the widespread nature of this phenomenon, the mechanism of induction remains poorly understood. The serpulid polychaete Hydroides elegans is a well established model for investigating bacteria-induced larval development. A broad range of biofilm bacterial species elicit larval metamorphosis in H. elegans via at least two mechanisms, including outer membrane vesicles (OMVs) and complexes of phage-tail bacteriocins. We investigated the interaction between larvae of H. elegans and the inductive bacterium Cellulophaga lytica, which produces an abundance of OMVs but not phage-tail bacteriocins. We asked whether the OMVs of C. lytica induce larval settlement due to cell membrane components or through delivery of specific cargo. Employing a biochemical structure­function approach with a strong ecological focus, the cells and OMVs produced by C. lytica were interrogated to determine the class of the inductive compounds. Here, we report that larvae of H. elegans are induced to metamorphose by lipopolysaccharide produced by C. lytica. The widespread prevalence of lipopolysaccharide and its associated taxonomic and structural variability suggest it may be a broadly employed cue for bacterially induced larval settlement of marine invertebrates.


Asunto(s)
Lipopolisacáridos , Metamorfosis Biológica , Animales , Bacterias , Biopelículas , Invertebrados/fisiología , Larva/fisiología , Lipopolisacáridos/farmacología , Metamorfosis Biológica/fisiología
3.
BMC Plant Biol ; 24(1): 445, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38778277

RESUMEN

BACKGROUND: Acer is a taxonomically intractable and speciose genus that contains over 150 species. It is challenging to distinguish Acer species only by morphological method due to their abundant variations. Plastome and nuclear ribosomal DNA (nrDNA) sequences are recommended as powerful next-generation DNA barcodes for species discrimination. However, their efficacies were still poorly studied. The current study will evaluate the application of plastome and nrDNA in species identification and perform phylogenetic analyses for Acer. RESULT: Based on a collection of 83 individuals representing 55 species (c. 55% of Chinese species) from 13 sections, our barcoding analyses demonstrated that plastomes exhibited the highest (90.47%) species discriminatory power among all plastid DNA markers, such as the standard plastid barcodes matK + rbcL + trnH-psbA (61.90%) and ycf1 (76.19%). And the nrDNA (80.95%) revealed higher species resolution than ITS (71.43%). Acer plastomes show abundant interspecific variations, however, species identification failure may be due to the incomplete lineage sorting (ILS) and chloroplast capture resulting from hybridization. We found that the usage of nrDNA contributed to identifying those species that were unidentified by plastomes, implying its capability to some extent to mitigate the impact of hybridization and ILS on species discrimination. However, combining plastome and nrDNA is not recommended given the cytonuclear conflict caused by potential hybridization. Our phylogenetic analysis covering 19 sections (95% sections of Acer) and 128 species (over 80% species of this genus) revealed pervasive inter- and intra-section cytonuclear discordances, hinting that hybridization has played an important role in the evolution of Acer. CONCLUSION: Plastomes and nrDNA can significantly improve the species resolution in Acer. Our phylogenetic analysis uncovered the scope and depth of cytonuclear conflict in Acer, providing important insights into its evolution.


Asunto(s)
Acer , Código de Barras del ADN Taxonómico , ADN de Plantas , ADN Ribosómico , Filogenia , Acer/genética , Código de Barras del ADN Taxonómico/métodos , ADN Ribosómico/genética , ADN de Plantas/genética , Plastidios/genética , Especificidad de la Especie , Núcleo Celular/genética
4.
BMC Cancer ; 24(1): 655, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38811880

RESUMEN

PURPOSE: This study aims to compare treatment outcomes between neoadjuvant chemotherapy (NACT) followed by surgery and concurrent chemoradiotherapy (CCRT) in patients with stage IIB cervical squamous cell carcinoma (CSCC). MATERIALS AND METHODS: We conducted a retrospective cohort study involving patients with stage IIB CSCC treated at Guangxi Medical University Cancer Hospital between June 2012 and June 2019. We compared overall survival (OS), locoregional-free survival (LRFS), and distant metastasis-free survival (DMFS) between the NACT + surgery and CCRT groups. RESULTS: A total of 257 patients were enrolled: 165 underwent NACT + surgery and 92 received CCRT. Before propensity score matching, the NACT + surgery group exhibited lower 5-year OS (68.2% vs. 85.6%; hazard ratio [HR] = 2.50, 95% confidence interval [CI]: 1.26-4.96; P = 0.009), LRFS (85.2% vs. 96.9%; HR = 5.88, 95% CI: 1.33-25.94; P = 0.019), and DMFS (81.9% vs. 97.4%; HR = 6.65, 95% CI: 1.51-29.23; P = 0.012) compared to the CCRT group. After propensity score matching, OS, LRFS, and DMFS remained worse in the NACT + surgery group compared to the CCRT group. CONCLUSION: NACT followed by surgery is associated with decreased OS, LRFS, and DMFS compared to CCRT among patients with stage IIB CSCC.


Asunto(s)
Carcinoma de Células Escamosas , Quimioradioterapia , Terapia Neoadyuvante , Estadificación de Neoplasias , Neoplasias del Cuello Uterino , Humanos , Femenino , Neoplasias del Cuello Uterino/terapia , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/mortalidad , Estudios Retrospectivos , Terapia Neoadyuvante/métodos , Persona de Mediana Edad , Quimioradioterapia/métodos , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/mortalidad , Adulto , Anciano , Puntaje de Propensión , Resultado del Tratamiento
5.
BMC Cancer ; 24(1): 106, 2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38238689

RESUMEN

PURPOSE: To assess survival of treatment patterns based on concurrent chemoradiotherapy (CCRT) in patients with stage IIB cervical squamous cell carcinoma (CSCC). MATERIALS AND METHODS: Patients with stage IIB CSCC receiving CCRT were investigated from June 2012 to June 2019 in Guangxi Medical University Cancer Hospital. Baseline characteristics and treatment patterns were described. Survival between treatment patterns were compared using Kaplan-Meier methods. RESULTS: A total of 232 patients were included: 39.7% of patients received CCRT alone, 6.5% of patients received neoadjuvant chemotherapy (NACT) + CCRT, 45.6% of patients received CCRT + adjuvant chemotherapy (AC), and 8.2% of patients received NACT + CCRT + AC. CCRT + AC showed similar overall survival (OS; hazard ratio [HR] = 0.95, 95% confidence interval [CI]: 0.41-2.17; P = 0.894) and locoregional-free survival (LRFS; HR = 2.39, 95% CI: 0.45-12.63; P = 0.303) compared with CCRT. However, CCRT + AC had a worse distant metastasis-free survival (DMFS; HR = 5.39, 95% CI: 1.14-25.57; P = 0.034). After propensity score matching, CCRT + AC had comparable OS (HR = 0.89, 95% CI: 0.29-2.70; P = 0.833), LRFS (HR = 3.26, 95% CI: 0.30-35.38; P = 0.331), and DMFS (HR = 4.80, 95% CI: 0.55-42.26; P = 0.157) compared to CCRT. CONCLUSION: AC did not improve survival in patients with stage IIB CSCC receiving CCRT.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Nasofaríngeas , Neoplasias del Cuello Uterino , Femenino , Humanos , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma Nasofaríngeo/tratamiento farmacológico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/patología , China , Quimioradioterapia/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Nasofaríngeas/patología , Estudios Retrospectivos
6.
Langmuir ; 40(32): 16846-16854, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39094224

RESUMEN

Films of the discotic liquid crystalline hexabenzocoronene (HBC) derivative, HBC-1,3,5-Ph-C12, were prepared on the quartz substrate by the bar-coating method. Depending on the coating speed, regularly spaced stripes or continuous films were observed. In the former case, columns of the HBC derivatives align more along the stripes, which are perpendicular to the coating direction, whereas in the latter case, columns of the HBC derivatives in the film align more along the coating direction. These distinctive structures are confirmed via polarized optical microscopy (POM), polarized UV-vis spectroscopy, and grazing incidence small-angle X-ray scattering measurements.

7.
Inorg Chem ; 63(10): 4697-4706, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38407040

RESUMEN

Benefiting from the unique photoluminescence behavior of the lanthanide(III) ions and organic ligands, a lanthanide(III) metal-organic framework (Ln-MOF) material can simultaneously demonstrate photoluminescence of lanthanide(III) cations and organic molecules and endow its superior applications of fluorescence sensing behaviors. Herein, we present a europium(III) MOF material {[Eu2(BPTA)·(CH3COO)2·3DMA]·0.5DMA·3H2O}n (1) (where H4BPTA is 3,3',5,5'-biphenyltetracarboxylic acid) for photoluminescence performance of quantitatively sensing the inflammatory marker neopterin (Neo). The obtained 1 comprises Eu2(COO)4 paddlewheel secondary building units, which could be bridged by BPTA4- ligands to extend a 2D framework. The fluorescence titration indicates 1 can achieve simultaneous fluorescence behavior of Eu3+ ions and Neo via on-off ratiometric effects and thus could be exploited as the ratiometric fluorescence sensor matrix. Such a fluorescence phenomenon of 1 as a ratiometric sensor for quantitative detection of Neo via an on-off ratiometric effect is never observed in MOF chemistry. Moreover, naked-eye visible color variations of the fluorescence for 1 could be observed from red to blue with increasing concentrations of Neo, confirmed by fluorescent test strips as well as portable fluorescent hydrogels. And 1 also shows a low detection limit of 15.11 nM. A synergetic contribution of the competitive absorption, fluorescence resonance energy-transfer, and photoinduced electron-transfer mechanisms between Neo and the framework of 1 realizes the on-off ratiometric fluorescence behavior for Neo detection, supported by the UV-vis spectral overlap experiment and DFT calculations.

8.
Proc Natl Acad Sci U S A ; 118(10)2021 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-33653958

RESUMEN

A key question regarding the unconventional superconductivity of [Formula: see text] remains whether the order parameter is single- or two-component. Under a hypothesis of two-component superconductivity, uniaxial pressure is expected to lift their degeneracy, resulting in a split transition. The most direct and fundamental probe of a split transition is heat capacity. Here, we report measurement of heat capacity of samples subject to large and highly homogeneous uniaxial pressure. We place an upper limit on the heat-capacity signature of any second transition of a few percent of that of the primary superconducting transition. The normalized jump in heat capacity, [Formula: see text], grows smoothly as a function of uniaxial pressure, favoring order parameters which are allowed to maximize in the same part of the Brillouin zone as the well-studied van Hove singularity. Thanks to the high precision of our measurements, these findings place stringent constraints on theories of the superconductivity of [Formula: see text].

9.
Biomed Chromatogr ; 38(5): e5840, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38402901

RESUMEN

The incidence of colibacillosis in poultry is on the rise, significantly affecting the chicken industry. Ceftiofur sodium (CS) is frequently employed to treat this disease, resulting in lipopolysaccharide (LPS) buildup. Processing plays a vital role in traditional Chinese veterinary medicine. The potential intervention in liver injury by polysaccharides from the differently processed products of Angelica sinensis (PDPPAS) induced by combined CS and LPS remains unclear. This study aims to investigate the protective effect of PDPPAS on chicken liver injury caused by CS combined with LPS buildup and further identify the polysaccharides with the highest hepatoprotective activity in chickens. Furthermore, the study elucidates polysaccharides' intervention mechanism using tandem mass tag (TMT) proteomics and multiple reaction monitoring (MRM) methods. A total of 190 1-day-old layer chickens were randomly assigned into 12 groups, of which 14 chickens were in the control group and 16 in other groups, for a 10-day trial. The screening results showed that charred A. sinensis polysaccharide (CASP) had the most effective and the best hepatoprotective effect at 48 h. TMT proteomics and MRM validation results demonstrated that the intervention mechanism of the CASP high-dose (CASPH) intervention group was closely related to the protein expressions of FCER2, TBXAS1, CD34, AGXT, GCAT, COX7A2L, and CYP2AC1. Conclusively, the intervention mechanism of CASPH had multitarget, multicenter regulatory features.


Asunto(s)
Angelica sinensis , Pollos , Hígado , Polisacáridos , Proteómica , Espectrometría de Masas en Tándem , Animales , Angelica sinensis/química , Proteómica/métodos , Polisacáridos/farmacología , Polisacáridos/química , Polisacáridos/análisis , Espectrometría de Masas en Tándem/métodos , Hígado/efectos de los fármacos , Hígado/metabolismo , Proteoma/análisis , Proteoma/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/química , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control
10.
J Environ Manage ; 366: 121855, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39025005

RESUMEN

Anaerobic membrane bioreactor (AnMBR) offer promise in municipal wastewater treatment, with potential benefits including high-quality effluent, energy recovery, sludge reduction, and mitigating greenhouse gas emissions. However, AnMBR face hurdles like membrane fouling, low energy recovery, etc. In light of net-zero carbon target and circular economy strategy, this work sought to evaluate novel AnMBR configurations, focusing on performance, fouling mitigation, net-energy generation, and nutrients-enhancing integrated configurations, such as forward osmosis (FO), membrane distillation (MD), bioelectrochemical systems (BES), membrane photobioreactor (MPBR), and partial nitrification-anammox (PN/A). In addition, we highlight the essential role of AnMBR in advancing the circular economy and propose ideas for the water-energy-climate nexus. While AnMBR has made significant progress, challenges, such as fouling and cost-effectiveness persist. Overall, the use of novel configurations and energy recovery strategies can further improve the sustainability and efficiency of AnMBR systems, making them a promising technology for future sustainable municipal wastewater treatment.


Asunto(s)
Reactores Biológicos , Eliminación de Residuos Líquidos , Aguas Residuales , Eliminación de Residuos Líquidos/métodos , Anaerobiosis , Membranas Artificiales
11.
Bull Environ Contam Toxicol ; 113(2): 19, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39080019

RESUMEN

Environmental concentrations of antimicrobials can inhibit Cyanobacteria, but little is known about their effects on Cyanobacteria-blooming freshwater ecosystem. Here, a 21 days' outdoor freshwater mesocosm experiment was established to study effects of single and combined tetracycline, triclocarban and zinc at environmental concentrations on microbial community, microbial function and antimicrobial resistance using amplicon- and metagenomic-based methods. Results showed that three chemicals reshaped the microbial community with magnified effects by chemical combinations. Relative abundance of Cyanobacteria was decreased in all chemical groups, especially from 74.5 to 0.9% in combination of three chemicals. Microbial community networks were more simplified after exposure. Proteobacteria and Bacteroidetes predominated in Cyanobacteria-degraded ecosystems, and their relative abundances were significantly correlated with antibiotic resistome, suggesting that they might host antibiotic resistance genes. Notably, relative abundance (copy per 16 S rRNA gene) of total antibiotic resistome reached five to nine folds higher than the initial abundance in chemical-combined groups. The affected antibiotic resistance genes referred to a wide range of antibiotic classes. However, weak effects were detected on biocide/metal resistance and microbial virulence. Three chemicals posed complicated effects on microbial function, some of which had consistent variations across the groups, while some varied greatly in chemical groups. The findings highlight sensitivity of Cyanobacteria-blooming ecosystem to antimicrobials.


Asunto(s)
Carbanilidas , Cianobacterias , Ecosistema , Agua Dulce , Contaminantes Químicos del Agua , Zinc , Cianobacterias/efectos de los fármacos , Cianobacterias/genética , Zinc/toxicidad , Carbanilidas/toxicidad , Agua Dulce/microbiología , Contaminantes Químicos del Agua/toxicidad , Antibacterianos/toxicidad , Antibacterianos/farmacología , Tetraciclina/farmacología , Tetraciclina/toxicidad , Microbiota/efectos de los fármacos
12.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 46(3): 425-434, 2024 Jun.
Artículo en Zh | MEDLINE | ID: mdl-38953267

RESUMEN

Alzheimer's disease (AD) is a severe threat to human health and one of the three major causes of human death.Double-stranded RNA-dependent protein kinase (PKR) is an interferon-induced protein kinase involved in innate immunity.In the occurrence and development of AD,PKR is upregulated and continuously activated.On the one hand,the activation of PKR triggers an integrated stress response in brain cells.On the other hand,it indirectly upregulates the expression of ß-site amyloid precursor protein cleaving enzyme 1 and facilitates the accumulation of amyloid-ß protein (Aß),which could activate PKR activator to further activate PKR,thus forming a sustained accumulation cycle of Aß.In addition,PKR can promote Tau phosphorylation,thereby reducing microtubule stability in nerve cells.Inflammation in brain tissue,neurotoxicity resulted from Aß accumulation,and disruption of microtubule stability led to the progression of AD and the declines of memory and cognitive function.Therefore,PKR is a key molecule in the development and progression of AD.Effective PKR detection can aid in the diagnosis and prediction of AD progression and provide opportunities for clinical treatment.The inhibitors targeting PKR are expected to control the activity of PKR,thereby controlling the progression of AD.Therefore,PKR could be a target for the development of therapeutic drugs for AD.


Asunto(s)
Enfermedad de Alzheimer , eIF-2 Quinasa , Enfermedad de Alzheimer/metabolismo , Humanos , eIF-2 Quinasa/metabolismo , Péptidos beta-Amiloides/metabolismo , Proteínas tau/metabolismo , Fosforilación , Encéfalo/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo
13.
Mol Phylogenet Evol ; 189: 107928, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37714444

RESUMEN

The Irano-Turanian region is one of the world's richest floristic regions and the centre of diversity for numerous xerophytic plant lineages. However, we still have limited knowledge on the timing of evolution and biogeographic history of its flora, and potential drivers of diversification remain underexplored. To fill this knowledge gap, we focus on the Eurasian genus Jurinea (ca. 200 species), one of the largest plant radiations that diversified in the region. We applied a macroevolutionary integrative approach to explicitly test diversification hypotheses and investigate the relative roles of geography vs. ecology and niche conservatism vs. niche lability in speciation processes. To do so, we gathered a sample comprising 77% of total genus richness and obtained data about (1) its phylogenetic history, recovering 502 nuclear loci sequences; (2) growth forms; (3) ecological niche, compiling data of 21 variables for more than 2500 occurrences; and (4) paleoclimatic conditions, to estimate climatic stability. Our results revealed that climate was a key factor in the evolutionary dynamics of Jurinea. The main diversification and biogeographic events that occurred during past climate changes, which led to colder and drier conditions, are the following: (1) the origin of the genus (10.7 Ma); (2) long-distance dispersals from the Iranian Plateau to adjacent regions (∼7-4 Ma); and (3) the diversification shift during Pliocene-Pleistocene Transition (ca. 3 Ma), when net diversification rate almost doubled. Our results supported the pre-adaptation hypothesis, i.e., the evolutionary success of Jurinea was linked to the retention of the ancestral niche adapted to aridity. Interestingly, the paleoclimatic analyses revealed that in the Iranian Plateau long-term climatic stability favoured old-lineage persistence, resulting in current high species richness of semi-arid and cold adapted clades; whereas moderate climate oscillations stimulated allopatric diversification in the lineages distributed in the Circumboreal region. In contrast, growth form lability and high niche disparity among closely related species in the Central Asian clade suggest adaptive radiation to mountain habitats. In sum, the radiation of Jurinea is the result of both adaptive and non-adaptive processes influenced by climatic, orogenic and ecological factors.


Asunto(s)
Asteraceae , Evolución Biológica , Filogenia , Irán , Filogeografía
14.
Inorg Chem ; 62(35): 14168-14179, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37606309

RESUMEN

A lanthanide-based molecular crystalline material endows metal-organic frameworks (MOFs) with many fascinating applications such as fluorescence detection and CO2 chemical fixation. Herein, we describe and study a multipurpose europium(III) MOF with the formula of {[Eu2(TATAB)2]·2.5H2O·2DMF}n (Eu-MOF) (where H3TATAB is 4,4',4″-((1,3,5-triazine-2,4,6-triyl)tris(azanediyl))tribenzoic acid ligand) for photoluminescence sensor matrix and CO2 chemical fixation. This Eu-MOF features 1D square channels along the c direction with a pore size of ca.14.07 Å × 14.07 Å, occupied by lattice water and DMF molecules. The obtained Eu-MOF can achieve simultaneous luminescence of the H3TATAB ligand and Eu3+ ions, which can be developed as the sensor matrix for ratiometric fluorescence thermometry. The luminescence of the Eu-MOF demonstrates an obvious color change from red to yellow as temperature rises from 303 to 373 K and the Eu-MOF has a satisfying relative sensitivity of 3.21% K-1 and a small temperature uncertainty of 0.0093 K at 333 K. Moreover, sensitive detection of gossypol was achieved with a quenching constant Ksv of 1.18 × 105 M-1 and a detection limit of 4.61 µM. A combination of the competitive absorption and photoinduced electron transfer caused by host-guest interactions and strengthened π-π packing effect synergistically between gossypol molecules and the Eu-MOF skeleton realizes the "turn-off" sensing of gossypol. Importantly, the nature of the Eu-MOF allows showing CO2 chemical fixation under mild conditions. Thus, the Eu-MOF can be utilized as a multipurpose material for ratiometric fluorescence thermometry, quantitative gossypol detection, and CO2 chemical fixation.

15.
Phys Chem Chem Phys ; 25(41): 28034-28042, 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37846110

RESUMEN

Nanopore-based biomolecule detection has emerged as a promising and sought-after innovation, offering high throughput, rapidity, label-free analysis, and cost-effectiveness, with potential applications in personalized medicine. However, achieving efficient and tunable biomolecule capture into the nanopore remains a significant challenge. In this study, we employ all-atom molecular dynamics simulations to investigate the capture of double-stranded DNA (dsDNA) molecules into graphene nanopores with varying positive charges. We discover a non-monotonic relationship between the DNA capture rate and the charge of the graphene nanopore. Specifically, the capture rate initially decreases and then increases with an increase in nanopore charge. This behavior is primarily attributed to differences in the electrophoretic force, rather than the influence of electroosmosis or counterions. Furthermore, we also observe this non-monotonic trend in various ionic solutions, but not in ionless solutions. Our findings shed light on the design of novel DNA sequencing devices, offering valuable insights into enhancing biomolecule capture rates in nanopore-based sensing platforms.


Asunto(s)
Grafito , Nanoporos , ADN/análisis , Simulación de Dinámica Molecular , Electroforesis
16.
Gut ; 71(7): 1340-1349, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34489309

RESUMEN

OBJECTIVE: Circulating tumour DNA (ctDNA) sequencing is increasingly used in the clinical management of patients with colorectal cancer. However, the genomic heterogeneity in ctDNA during treatments and its impact on clinical outcomes remain largely unknown. DESIGN: We conducted a prospective cohort study (NCT04228614) of 171 patients with unresectable metastatic colorectal cancer (mCRC) who underwent first-line treatment and prospectively collected blood samples with or without tumour samples from patients at baseline and sequentially until disease progression or last follow-up. RESULTS: The RAS/BRAF alterations in paired baseline tissue and plasma samples from 63 patients displayed a favourable concordance (81.0%, 51/63). After a period of first-line treatment (median time between baseline and last liquid biopsy, 4.67 months), 42.6% (26/61) of RAS-mutant patients showed RAS clearance and 50.0% (5/10) of BRAF-mutant patients showed BRAF clearance, while 3.6% (3/84) and 0.7% (1/135) of patients showed new RAS or BRAF mutations in ctDNA. Patients with plasma RAS/BRAF clearance showed similar progression-free survival (PFS) and overall survival (OS) with patients who remained RAS/BRAF wild-type, while much better outcomes than those who remained RAS/BRAF mutant. Patients who gained new RAS/BRAF mutations showed similar prognosis as those who maintained RAS/BRAF mutations, and shorter PFS and OS than those who remained RAS/BRAF wild-type. CONCLUSION: This prospective, serial and large-scale ctDNA profiling study reveals the temporal heterogeneity of mCRC-related somatic variants, which should be given special attention in clinical practice, as evidenced by the finding that the shift in plasma RAS/BRAF mutational status can yield a drastic change in survival outcomes.


Asunto(s)
ADN Tumoral Circulante , Neoplasias del Colon , Neoplasias Colorrectales , Neoplasias del Recto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/genética , ADN Tumoral Circulante/genética , Neoplasias del Colon/tratamiento farmacológico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Genómica , Humanos , Mutación , Estudios Prospectivos , Proteínas Proto-Oncogénicas B-raf/genética
17.
Anal Bioanal Chem ; 414(22): 6541-6555, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35819475

RESUMEN

The presence of benzothiazoles (BTHs) and organic ultraviolet filters (UV filters) in aquatic ecosystems has emerged as a significant environmental issue, requiring urgent and efficient determination methods. A new, rapid, and sensitive determination method using gas chromatography triple quadrupole mass spectrometer (GC-MS/MS) was developed for the simultaneous extraction and analysis of 10 commonly used BTHs and 10 organic UV filters in surface water, wastewater, sediment, and sludge. For aqueous samples, solid-phase extraction (SPE) method was employed with optimizing of SPE cartridge type, pH, and elution solvent. For solid samples, ultrasonic extraction-solid-phase extraction purification (UE-SPE) and pressurized liquid extraction (PLE) methods were compared. And extraction conditions for ultrasonic extraction method (extraction solvents and extraction times) and PLE method (extraction temperatures and extraction cycles) were optimized. The limits of quantification for the 20 target compounds in surface water and wastewater were 0.01-2.12 ng/L and 0.05-6.14 ng/L, while those for sediment and sludge with UE-SPE method were 0.04-5.88 ng/g and 0.22-6.61 ng/g, respectively. Among the 20 target compounds, the recoveries ranged from 70 to 130% were obtained for 16, 15, 15, and 15 analytes in the matrix-spiked samples of surface water, wastewater, sediment, and sludge with three levels, respectively. And the precision was also acceptable with relative standard deviation (RSD) below 20% for all analytes. The developed methods were applied for the determination and quantification of target compounds in surface water, sediment, wastewater, and sludge samples collected from two wastewater treatment plants (WWTPs) and the Pearl River in Guangzhou, China. BTHs were frequently detected in surface water and wastewater, while UV filters were mainly found in sediment and sludge. Benzotriazole (BT) and 2-hydroxybenzothiazole (2-OH-BTH) were the two major BTHs in influent wastewater and surface water, respectively, with concentrations up to 966 and 189 ng/L. As for sediment and sludge, 2-(2'-hydroxy-5'-octylphenyl)-benzotriazole (UV-329) was a predominant chemical, detected at concentrations of 111 and 151 ng/g, respectively.


Asunto(s)
Aguas del Alcantarillado , Contaminantes Químicos del Agua , Benzotiazoles/análisis , Ecosistema , Cromatografía de Gases y Espectrometría de Masas , Aguas del Alcantarillado/análisis , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/métodos , Aguas Residuales/análisis , Agua/química , Contaminantes Químicos del Agua/análisis
18.
Proc Natl Acad Sci U S A ; 116(27): 13404-13413, 2019 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-31213539

RESUMEN

BRUCE/Apollon is a membrane-associated inhibitor of apoptosis protein that is essential for viability and has ubiquitin-conjugating activity. On initiation of apoptosis, the ubiquitin ligase Nrdp1/RNF41 promotes proteasomal degradation of BRUCE. Here we demonstrate that BRUCE together with the proteasome activator PA28γ causes proteasomal degradation of LC3-I and thus inhibits autophagy. LC3-I on the phagophore membrane is conjugated to phosphatidylethanolamine to form LC3-II, which is required for the formation of autophagosomes and selective recruitment of substrates. SIP/CacyBP is a ubiquitination-related protein that is highly expressed in neurons and various tumors. Under normal conditions, SIP inhibits the ubiquitination and degradation of BRUCE, probably by blocking the binding of Nrdp1 to BRUCE. On DNA damage by topoisomerase inhibitors, Nrdp1 causes monoubiquitination of SIP and thus promotes apoptosis. However, on starvation, SIP together with Rab8 enhances the translocation of BRUCE into the recycling endosome, formation of autophagosomes, and degradation of BRUCE by optineurin-mediated autophagy. Accordingly, deletion of SIP in cultured cells reduces the autophagic degradation of damaged mitochondria and cytosolic protein aggregates. Thus, by stimulating proteasomal degradation of LC3-I, BRUCE also inhibits autophagy. Conversely, SIP promotes autophagy by blocking BRUCE-dependent degradation of LC3-I and by enhancing autophagosome formation and autophagic destruction of BRUCE. These actions of BRUCE and SIP represent mechanisms that link the regulation of autophagy and apoptosis under different conditions.


Asunto(s)
Autofagia , Proteínas de Unión al Calcio/metabolismo , Proteínas Inhibidoras de la Apoptosis/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Animales , Apoptosis , Autofagosomas/metabolismo , Daño del ADN , Fibroblastos , Técnicas de Silenciamiento del Gen , Células HEK293 , Humanos , Ratones , Ubiquitinación
19.
J Environ Manage ; 316: 115243, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35598450

RESUMEN

Vitrification technology provides a solution for the issue of safe disposal of hazardous waste containing harmful chemical composition and organic pollutants. This review discusses application of vitrification technologies to treat hazardous waste including, asbestos, fly ash, electronic sludge, nuclear waste, medical waste and radioactive waste. Vitrification processes via Joule heating, microwave heating, plasma technology, electric arc furnaces and incinerators are compared herein. Stabilization of hazardous waste can be achieved by vitrification with the addition of flux agents/additives. Furthermore, crystalline structures, containing the silicate-glass network, are formed as a result of vitrification, depending on the type of flux agents/additives used. In addition, the concentration of heavy metals can be degraded in the final residue and leaching resistance can be achieved. Moreover, energy consumption, pollution prevention and the foreground of the practical application of vitrification are discussed. Vitrification with the advantage of encapsulating pollutants from the hazardous waste is proven to be a promising approach for hazardous waste treatment.


Asunto(s)
Contaminantes Ambientales , Metales Pesados , Eliminación de Residuos , Ceniza del Carbón/química , Residuos Peligrosos , Incineración , Metales Pesados/química , Residuos Sólidos , Tecnología , Vitrificación
20.
Pharmacogenomics J ; 21(2): 200-215, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33097827

RESUMEN

The correlations between hydroxytryptamine receptor 2A (HTR2A) gene polymorphisms (1438A/G, 102T/C, and rs7997012G/A) and the safety and efficacy of antidepressants in depression patients were constantly reported, but conclusions are debatable. This meta-analysis ascertained forty-two studies on the efficacy (including response and remission) and side-effect issued before February 2020. Pooled analyses indicated significant associations of 1438A/G polymorphism (16 studies, 1931 subjects) and higher response within dominant model (OR: 1.40, 95% CI: 1.12-1.76); rs7997012G/A polymorphism (nine studies, 1434 subjects) and higher remission in overall models (dominant model: OR: 1.30, 95% CI: 1.01-1.66; recessive model: OR: 2.20, 95% CI: 1.53-3.16; homozygote model: OR: 2.73, 95% CI: 1.78-4.17); 102T/C polymorphism (eight studies, 804 subjects) and reduced risk of side-effect within recessive (OR: 0.57, 95% CI: 0.4-0.83) and homozygote models (OR: 0.54, 95% CI: 0.29-0.99). For depression patients, genotyping of HTR2A polymorphisms is a promising tool for estimating the outcome and side-effect of antidepressants.


Asunto(s)
Antidepresivos/efectos adversos , Antidepresivos/uso terapéutico , Depresión/tratamiento farmacológico , Depresión/genética , Polimorfismo de Nucleótido Simple/genética , Receptor de Serotonina 5-HT2A/genética , Adolescente , Adulto , Anciano , Femenino , Predisposición Genética a la Enfermedad/genética , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
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