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1.
Sci Total Environ ; 944: 173804, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-38848922

RESUMEN

Soil and groundwater contamination by organic pollutants from chemical plants presents significant risks to both environmental and human health. We report a significant field trial where a chemical plant in operation showed soil and groundwater pollution, as verified by sampling and laboratory tests. While many remediation methods are effective, they often require the temporary shutdown of plant operations to install necessary equipment. This paper introduces a novel combination of low-disturbance contaminant remediation technologies, including groundwater circulation well (GCW), pump and treat (P&T), and in-situ chemical oxidation (ISCO) technologies, that can be applied on the premises of an active plant without halting production. The groundwater with dissolved contaminants is removed through P&T and GCW, while GCW enhances ISCO that focus on eliminating the remaining hard-to-pump contaminants. Results show: (1) after two years of remediation effort, the contaminant levels in soil and groundwater were significantly reduced; (2) the average concentration reduction rate of four contaminants, including 1,2-dichloroethane, methylbenzene, ethylbenzene, and M&P-xylene, exceeds 98 %; (3) the presented remediation strategy results in the improvement of remediation efficiency. Specifically, the concentration of 1,2-dichloroethane in observation wells dropped from 40,550.7 µg/L to 44.6 µg/L. This study offers a first-of-its-kind commercial deployment of a GCW-based remediation strategy in an active plant setting. Moreover, the combined remediation approach presented here can serve as a model for designing contaminant remediation projects that require minimal operational disruption.

2.
Cereb Cortex ; 34(2)2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38314605

RESUMEN

The aim of this study was to investigate brain structure and corresponding static and dynamic functional connectivity (sFC & dFC) abnormalities in untreated, first-episode pediatric idiopathic generalized epilepsy (IGE), with the goal of better understanding the underlying pathological mechanisms of IGE. Thirty-one children with IGE and 31 age-matched healthy controls (HC) were recruited. Structural magnetic resonance imaging (sMRI) data were acquired, and voxel-based morphometry (VBM) analysis were performed to reveal abnormal gray matter volume (GMV). Moreover, sFC and dFC analyses were conducted using the brain areas exhibiting abnormal GMV as seed regions to explore abnormal functional couplings. Compared to HC, the IGE group exhibited increased GMV in left middle cingulate cortex (MCC) and right parahippocampus (ParaHipp). In addition, the analyses of dFC and sFC with MCC and ParaHipp as seeds revealed more extensive functional connectivity (FC) changes in dFC. Notably, the structurally and functionally abnormal brain areas were primarily localized in the default mode network (DMN). However, our study did not find any significant associations between these altered neuroimaging measurements and clinical outcomes. This study uncovered microstructural changes as well as corresponding sFC and dFC changes in patients with new-onset, untreated pediatric IGE. The affected brain regions were primarily located within the DMN, highlighting the DMN's crucial role in the development of pediatric IGE.


Asunto(s)
Mapeo Encefálico , Epilepsia Generalizada , Humanos , Niño , Mapeo Encefálico/métodos , Encéfalo , Imagen por Resonancia Magnética/métodos , Inmunoglobulina E
3.
Chem Rev ; 124(3): 889-928, 2024 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-38231473

RESUMEN

With unlimited selectivity, full post-translational chemical control of biology would circumvent the dogma of genetic control. The resulting direct manipulation of organisms would enable atomic-level precision in "editing" of function. We argue that a key aspect that is still missing in our ability to do this (at least with a high degree of control) is the selectivity of a given chemical reaction in a living organism. In this Review, we systematize existing illustrative examples of chemical selectivity, as well as identify needed chemical selectivities set in a hierarchy of anatomical complexity: organismo- (selectivity for a given organism over another), tissuo- (selectivity for a given tissue type in a living organism), cellulo- (selectivity for a given cell type in an organism or tissue), and organelloselectivity (selectivity for a given organelle or discrete body within a cell). Finally, we analyze more traditional concepts such as regio-, chemo-, and stereoselective reactions where additionally appropriate. This survey of late-stage biomolecule methods emphasizes, where possible, functional consequences (i.e., biological function). In this way, we explore a concept of late-stage functionalization of living organisms (where "late" is taken to mean at a given state of an organism in time) in which programmed and selective chemical reactions take place in life. By building on precisely analyzed notions (e.g., mechanism and selectivity) we believe that the logic of chemical methodology might ultimately be applied to increasingly complex molecular constructs in biology. This could allow principles developed at the simple, small-molecule level to progress hierarchically even to manipulation of physiology.


Asunto(s)
Proteómica
4.
ACS Cent Sci ; 9(3): 405-416, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36968537

RESUMEN

Chemical post-translational methods allow convergent side-chain editing of proteins without needing to resort to genetic intervention. Current approaches that allow the creation of constitutionally native side chains via C-C bond formation, using off-protein carbon-centered C· radicals added to unnatural amino acid radical acceptor (SOMOphile, singly occupied molecular orbital (SOMO)) "tags" such as dehydroalanine, are benign and wide-ranging. However, they also typically create epimeric mixtures of d/l-residues. Here, we describe a light-mediated desulfurative method that, through the creation and reaction of stereoretained on-proteinl-alanyl Cß· radicals, allows Cß-Hγ, Cß-Oγ, Cß-Seγ, Cß-Bγ, and Cß-Cγ bond formation to flexibly generate site-selectively edited proteins with full retention of native stereochemistry under mild conditions from a natural amino acid precursor. This methodology shows great potential to explore protein side-chain diversity and function and in the construction of useful bioconjugates.

5.
Small Methods ; 7(6): e2201554, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36929696

RESUMEN

Metal-organic frameworks (MOFs) with inherent porosity, controllable structures, and designable components are recognized as attractive platforms for designing advanced electrodes of high-performance potassium-ion batteries (PIBs). However, the poor electrical conductivity and low theoretical capacity of many MOFs lead to inferior electrochemical performance. Herein, for the first time, a confined bismuth-organic framework with 3D porous matrix structure (Bi-MOF) as anode for PIBs via a facile wet-chemical approach is reported. Such a porous structure design with double active centers can simultaneously ensure the structure integrity and efficient charge transport to enable high-capacity electrode with super cycling life. As a result, the Bi-MOF for PIBs exhibits high reversible capacity (419 mAh g-1 at 0.1 A g-1 ), outstanding cycling stability (315 mAh g-1 at 0.5 A g-1 after 1200 cycles), and excellent full battery performance (a high energy density of 183 Wh kg-1 is achieved, outperforming all reported metal-based anodes for PIBs). Moreover, the K+ storage mechanisms of the Bi-MOF are further unveiled by in situ Raman, ex situ high-resolution transmission electron microscopy, and ex situ Fourier-transform infrared spectroscopy. This ingenious electrode design may provide further guidance for the application of MOF in energy storage systems.

6.
Nat Commun ; 14(1): 842, 2023 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-36792600

RESUMEN

RNA ligases are present across all forms of life. While enzymatic RNA ligation between 5'-PO4 and 3'-OH termini is prevalent in viruses, fungi, and plants, such RNA ligases are yet to be identified in vertebrates. Here, using a nucleotide-based chemical probe targeting human AMPylated proteome, we have enriched and identified the hitherto uncharacterised human protein chromosome 12 open reading frame 29 (C12orf29) as a human enzyme promoting RNA ligation between 5'-PO4 and 3'-OH termini. C12orf29 catalyses ATP-dependent RNA ligation via a three-step mechanism, involving tandem auto- and RNA AMPylation. Knock-out of C12ORF29 gene impedes the cellular resilience to oxidative stress featuring concurrent RNA degradation, which suggests a role of C12orf29 in maintaining RNA integrity. These data provide the groundwork for establishing a human RNA repair pathway.


Asunto(s)
ARN Ligasa (ATP) , ARN , Animales , Humanos , ARN Ligasa (ATP)/genética , ARN Ligasa (ATP)/metabolismo , ARN/genética
7.
Angew Chem Int Ed Engl ; 62(8): e202213279, 2023 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-36524454

RESUMEN

Diadenosine polyphosphates (Apn As) are non-canonical nucleotides whose cellular concentrations increase during stress and are therefore termed alarmones, signaling homeostatic imbalance. Their cellular role is poorly understood. In this work, we assessed Apn As for their usage as cosubstrates for protein AMPylation, a post-translational modification in which adenosine monophosphate (AMP) is transferred to proteins. In humans, AMPylation mediated by the AMPylator FICD with ATP as a cosubstrate is a response to ER stress. Herein, we demonstrate that Ap4 A is proficiently consumed for AMPylation by FICD. By chemical proteomics using a new chemical probe, we identified new potential AMPylation targets. Interestingly, we found that AMPylation targets of FICD may differ depending on the nucleotide cosubstrate. These results may suggest that signaling at elevated Ap4 A levels during cellular stress differs from when Ap4 A is present at low concentrations, allowing response to extracellular cues.


Asunto(s)
Guanosina Pentafosfato , Proteínas , Humanos , Guanosina Pentafosfato/metabolismo , Proteínas/metabolismo , Adenosina Monofosfato/metabolismo , Fosfatos de Dinucleósidos/metabolismo , Procesamiento Proteico-Postraduccional
8.
Psychoradiology ; 3: kkad014, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38666130

RESUMEN

Background: Major depressive disorder (MDD) has different clinical presentations in males and females. However, the neuroanatomical mechanisms underlying these sex differences are not fully understood. Objective: The purpose of present study was to explore the sex differences in brain cortical thickness (CT) and surface area (SA) of MDD and the relationship between these differences and clinical manifestations in different gender. Methods: High-resolution T1-weighted images were acquired from 61 patients with MDD and 61 healthy controls (36 females and 25 males, both). The sex differences in CT and SA were obtained using the FreeSurfer software and compared between every two groups by post hoc test. Spearman correlation analysis was also performed to explore the relationships between these regions and clinical characteristics. Results: In male patients with MDD, the CT of the right precentral was thinner compared to female patients, although this did not survive Bonferroni correction. The SA of several regions, including right superior frontal, medial orbitofrontal gyrus, inferior frontal gyrus triangle, superior temporal, middle temporal, lateral occipital gyrus, and inferior parietal lobule in female patients with MDD was smaller than that in male patients (P < 0.01 after Bonferroni correction). In female patients, the SA of the right superior temporal (r = 0.438, P = 0.008), middle temporal (r = 0.340, P = 0.043), and lateral occipital gyrus (r = 0.372, P = 0.025) were positively correlated with illness duration. Conclusion: The current study provides evidence of sex differences in CT and SA in patients with MDD, which may improve our understanding of the sex-specific neuroanatomical changes in the development of MDD.

9.
Front Neurosci ; 16: 814410, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35431791

RESUMEN

Some important clinical characteristics of major depressive disorder (MDD) differ between sexes. We explored abnormal spontaneous neuronal activity in MDD patients using the amplitude of low-frequency fluctuation (ALFF) and its relationship to clinical manifestations in male and female patients, to seek the neural mechanisms underlying sex-related differences in depression. Twenty-five male MDD patients, 36 female MDD patients, and 25 male and 36 female matched healthy controls (HC) were included. The ALFF difference was investigated among four groups, and partial correlation analysis was used to explore a possible clinical relevance. The main effect results of sex difference were located in the bilateral caudate nucleus and posterior cingulate gyrus. Post hoc comparisons found that the male MDD patients showed decreased ALFF in the bilateral caudate nucleus and posterior cingulate gyrus when compared with female MDD patients/female HCs, and female MDD patients showed increased ALFF in the bilateral caudate nucleus and posterior cingulate gyrus when compared with male HCs. The average ALFF of the right caudate nucleus was positively correlated with illness duration in female MDD patients. Our results suggest that the sex-specific abnormal brain activity might be a potential pathomechanism of different symptoms in male and female MDD patients.

10.
Nat Commun ; 12(1): 5808, 2021 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-34608152

RESUMEN

The nucleotides diadenosine triphosphate (Ap3A) and diadenosine tetraphosphate (Ap4A) are formed in prokaryotic and eukaryotic cells. Since their concentrations increase significantly upon cellular stress, they are considered to be alarmones triggering stress adaptive processes. However, their cellular roles remain elusive. To elucidate the proteome-wide interactome of Ap3A and Ap4A and thereby gain insights into their cellular roles, we herein report the development of photoaffinity-labeling probes and their employment in chemical proteomics. We demonstrate that the identified ApnA interactors are involved in many fundamental cellular processes including carboxylic acid and nucleotide metabolism, gene expression, various regulatory processes and cellular response mechanisms and only around half of them are known nucleotide interactors. Our results highlight common functions of these ApnAs across the domains of life, but also identify those that are different for Ap3A or Ap4A. This study provides a rich source for further functional studies of these nucleotides and depicts useful tools for characterization of their regulatory mechanisms in cells.


Asunto(s)
Fosfatos de Dinucleósidos/metabolismo , Proteómica , Adenosina Trifosfato/metabolismo , Fosfatos de Dinucleósidos/química , Endorribonucleasas/metabolismo , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Células HEK293 , Humanos , L-Lactato Deshidrogenasa/metabolismo , Fosfoglicerato Quinasa/metabolismo , Etiquetas de Fotoafinidad/síntesis química , Etiquetas de Fotoafinidad/química , Etiquetas de Fotoafinidad/metabolismo , Unión Proteica , Enzimas Activadoras de Ubiquitina/metabolismo
11.
Chemistry ; 21(46): 16395-9, 2015 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-26418889

RESUMEN

A cationic cobalt(III)-catalyzed direct C-H amidation of unactivated (hetero)arenes and alkenes by using 1,4,2-dioxazol-5-ones as the amidating reagent has been developed. This transformation proceeds efficiently under external oxidant-free conditions with a broad substrate scope. Moreover, 6-arylpurine compounds, which often exhibit high potency in antimycobacterial, cytostatic, and anti-HCV activities, can be smoothly amidated, thus offering a mild protocol for their late stage functionalization.

12.
Org Lett ; 17(12): 2886-9, 2015 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-26010555

RESUMEN

An efficient and practical system for inexpensive bromination and iodination of arenes as well as heteroarenes by using readily available dimethyl sulfoxide (DMSO) and HX (X = Br, I) reagents is reported. This mild oxidative system demonstrates a versatile protocol for the synthesis of aryl halides. HX (X = Br, I) are employed as halogenating reagents when combined with DMSO which participates in the present chemistry as a mild and inexpensive oxidant. This oxidative system is amenable to late-stage bromination of natural products. The kilogram-scale experiment (>95% yield) shows great potential for industrial application.


Asunto(s)
Ácidos/química , Derivados del Benceno/química , Productos Biológicos/síntesis química , Dimetilsulfóxido/química , Ácido Bromhídrico/química , Compuestos de Yodo/química , Productos Biológicos/química , Halogenación , Estructura Molecular , Oxidación-Reducción
13.
Org Lett ; 17(9): 2206-9, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25875319

RESUMEN

An intermolecular nitrogenation reaction toward the synthesis of phenanthridines has been developed. This metal-free protocol provides a novel nitrogen-incorporation transformation using azides as the nitrogen source. Phenanthridines, which are of great interest in pharmaceutical and medicinal chemistry, are synthesized efficiently in one step. Moreover, the byproducts derived from the Schmidt reaction are inhibited, which further demonstrated the high chemoselectivity of this transformation.


Asunto(s)
Azidas/química , Nitrógeno/química , Fenantridinas/síntesis química , Metales/química , Estructura Molecular , Fenantridinas/química
14.
J Am Chem Soc ; 136(42): 14858-65, 2014 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-25251943

RESUMEN

The Cu-catalyzed aerobic oxidative esterification of simple ketones via C-C bond cleavage has been developed. Varieties of common ketones, even inactive aryl long-chain alkyl ketones, are selectively converted into esters. The reaction tolerates a wide range of alcohols, including primary and secondary alcohols, chiral alcohols with retention of the configuration, electron-deficient phenols, as well as various natural alcohols. The usage of inexpensive copper catalyst, broad substrate scope, and neutral and open air conditions make this protocol very practical. (18)O labeling experiments reveal that oxygenation occurs during this transformation. Preliminary mechanism studies indicate that two novel pathways are mainly involved in this process.


Asunto(s)
Aire , Cetonas/química , Oxígeno/química , Catálisis , Ésteres , Oxidación-Reducción , Especificidad por Sustrato
15.
Chem Commun (Camb) ; 50(31): 4115-8, 2014 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-24622694

RESUMEN

A novel iron-catalyzed efficient approach to construct sulfone-containing oxindoles, which play important roles in the structural library design and drug discovery, has been developed. The use of readily available benzenesulfinic acids, an inexpensive iron salt as the catalyst, and air as the oxidant makes this sulfur incorporation protocol very efficient and practical.


Asunto(s)
Alquenos/química , Indoles/química , Hierro/química , Aire , Catálisis , Oxidantes/química , Oxindoles , Oxígeno/química , Ácidos Sulfínicos/química , Sulfonas/química
16.
Chem Commun (Camb) ; 50(5): 554-6, 2014 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-24266027

RESUMEN

A novel and direct metal-free nitro-carbocyclization of activated alkenes leading to valuable nitro-containing oxindoles via cascade C-N and C-C bond formation has been developed. The mechanistic study indicates that the initial NO and NO2 radical addition and the following C-H functionalization processes are involved in this transformation.


Asunto(s)
Indoles/química , Alquenos/química , Carbono/química , Ciclización , Metales/química , Nitrógeno/química , Oxidación-Reducción , Oxindoles
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