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1.
Immunity ; 49(4): 740-753.e7, 2018 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-30314759

RESUMEN

Caspase-11, a cytosolic endotoxin (lipopolysaccharide: LPS) receptor, mediates pyroptosis, a lytic form of cell death. Caspase-11-dependent pyroptosis mediates lethality in endotoxemia, but it is unclear how LPS is delivered into the cytosol for the activation of caspase-11. Here we discovered that hepatocyte-released high mobility group box 1 (HMGB1) was required for caspase-11-dependent pyroptosis and lethality in endotoxemia and bacterial sepsis. Mechanistically, hepatocyte-released HMGB1 bound LPS and targeted its internalization into the lysosomes of macrophages and endothelial cells via the receptor for advanced glycation end-products (RAGE). Subsequently, HMGB1 permeabilized the phospholipid bilayer in the acidic environment of lysosomes. This resulted in LPS leakage into the cytosol and caspase-11 activation. Depletion of hepatocyte HMGB1, inhibition of hepatocyte HMGB1 release, neutralizing extracellular HMGB1, or RAGE deficiency prevented caspase-11-dependent pyroptosis and death in endotoxemia and bacterial sepsis. These findings indicate that HMGB1 interacts with LPS to mediate caspase-11-dependent pyroptosis in lethal sepsis.


Asunto(s)
Caspasas/inmunología , Endotoxinas/inmunología , Proteína HMGB1/inmunología , Piroptosis/inmunología , Sepsis/inmunología , Animales , Caspasas/genética , Caspasas/metabolismo , Células Cultivadas , Células Endoteliales/inmunología , Células Endoteliales/metabolismo , Endotoxinas/metabolismo , Células HEK293 , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Humanos , Lipopolisacáridos/inmunología , Lipopolisacáridos/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Receptor para Productos Finales de Glicación Avanzada/inmunología , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Sepsis/genética , Sepsis/metabolismo , Células THP-1
2.
Nat Immunol ; 14(8): 793-803, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23832071

RESUMEN

The cell-to-cell transmission of viral resistance is a potential mechanism for amplifying the interferon-induced antiviral response. In this study, we report that interferon-α (IFN-α) induced the transfer of resistance to hepatitis B virus (HBV) from nonpermissive liver nonparenchymal cells (LNPCs) to permissive hepatocytes via exosomes. Exosomes from IFN-α-treated LNPCs were rich in molecules with antiviral activity. Moreover, exosomes from LNPCs were internalized by hepatocytes, which mediated the intercellular transfer of antiviral molecules. Finally, we found that exosomes also contributed to the antiviral response of IFN-α to mouse hepatitis virus A59 and adenovirus in mice. Thus, we propose an antiviral mechanism of IFN-α activity that involves the induction and intercellular transfer of antiviral molecules via exosomes.


Asunto(s)
Exosomas/virología , Virus de la Hepatitis B/inmunología , Hepatitis B/inmunología , Interferón-alfa/farmacología , Hígado/virología , Animales , Exosomas/inmunología , Células Hep G2 , Hepatitis B/tratamiento farmacológico , Humanos , Immunoblotting , Hígado/inmunología , Ratones , Transducción de Señal/inmunología , Replicación Viral/inmunología
3.
Chem Soc Rev ; 53(7): 3273-3301, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38507263

RESUMEN

Oral diseases are prevalent but challenging diseases owing to the highly movable and wet, microbial and inflammatory environment. Polymeric materials are regarded as one of the most promising biomaterials due to their good compatibility, facile preparation, and flexible design to obtain multifunctionality. Therefore, a variety of strategies have been employed to develop materials with improved therapeutic efficacy by overcoming physicobiological barriers in oral diseases. In this review, we summarize the design strategies of polymeric biomaterials for the treatment of oral diseases. First, we present the unique oral environment including highly movable and wet, microbial and inflammatory environment, which hinders the effective treatment of oral diseases. Second, a series of strategies for designing polymeric materials towards such a unique oral environment are highlighted. For example, multifunctional polymeric materials are armed with wet-adhesive, antimicrobial, and anti-inflammatory functions through advanced chemistry and nanotechnology to effectively treat oral diseases. These are achieved by designing wet-adhesive polymers modified with hydroxy, amine, quinone, and aldehyde groups to provide strong wet-adhesion through hydrogen and covalent bonding, and electrostatic and hydrophobic interactions, by developing antimicrobial polymers including cationic polymers, antimicrobial peptides, and antibiotic-conjugated polymers, and by synthesizing anti-inflammatory polymers with phenolic hydroxy and cysteine groups that function as immunomodulators and electron donors to reactive oxygen species to reduce inflammation. Third, various delivery systems with strong wet-adhesion and enhanced mucosa and biofilm penetration capabilities, such as nanoparticles, hydrogels, patches, and microneedles, are constructed for delivery of antibiotics, immunomodulators, and antioxidants to achieve therapeutic efficacy. Finally, we provide insights into challenges and future development of polymeric materials for oral diseases with promise for clinical translation.


Asunto(s)
Antiinfecciosos , Polímeros , Polímeros/química , Materiales Biocompatibles/química , Antiinflamatorios , Factores Inmunológicos
4.
Biochem Biophys Res Commun ; 707: 149726, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38493747

RESUMEN

Real-time reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) is an important method for the early diagnosis of coronavirus disease 2019 (COVID-19). This study investigated the effects of storage solution, temperature and detection time on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid detection by RT-qPCR. Various concentrations of SARS-CoV-2 were added to inactive and non-inactive storage solution and the viral suspensions were stored at various temperatures (room temperature, 4, -20 and -80 °C). Then, at five different detection time points, the Ct values were determined by RT-qPCR. Active and inactive storage solutions and storage temperature have a great impact on the detection of N gene of SARS-CoV-2 at different concentration corridors but have little impact on the ORF gene. The storage time has a greater impact on the N gene and ORF gene at high concentrations but has no effect on the two genes at low concentrations. In conclusion, storage temperature, storage time and storage status (inactivated, non-inactivated) have no effect on the nucleic acid detection of SARS-CoV-2 at the same concentration. For different concentrations of SARS-CoV-2, the detection of N gene is mainly affected.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/diagnóstico , Temperatura , ARN Viral/genética , ARN Viral/análisis , Prueba de COVID-19 , Sensibilidad y Especificidad , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos
5.
Small ; 20(14): e2308600, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37974554

RESUMEN

The rise of MXene-based materials with fascinating physical and chemical properties has attracted wide attention in the field of biomedicine, because it can be exploited to regulate a variety of biological processes. The biomedical applications of MXene are still in its infancy, nevertheless, the comprehensive evaluation of MXene's biosafety is desperately needed. In this review, the composition and the synthetic methods of MXene materials are first introduced from the view of biosafety. The evaluation of the interaction between MXene and cells, as well as the safety of different forms of MXene applied in vivo are then discussed. This review provides a basic understanding of MXene biosafety and may bring new inspirations to the future applications of MXene-based materials in biomedicine.


Asunto(s)
Contención de Riesgos Biológicos , Nitritos , Elementos de Transición
6.
Fungal Genet Biol ; 173: 103910, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38897560

RESUMEN

The homologous recombination strategy has a long history of editing Saccharomyces cerevisiae target genes. The application of CRISPR/Cas9 strategy to editing target genes in S. cerevisiae has also received a lot of attention in recent years. All findings seem to indicate that editing relevant target genes in S. cerevisiae is an extremely easy event. In this study, we systematically analyzed the advantages and disadvantages of homologous recombination (HR) strategy, CRISPR/Cas9 strategy, and CRISPR/Cas9 combined homology-mediated repair (CRISPR/Case9-HDR) strategy in knocking out BY4742 ade2. Our data showed that when the ade2 was knocked out by HR strategy, a large number of clones appeared to be off-target, and 10 %-80 % of the so-called knockout clones obtained were heteroclones. When the CRISPR/Cas9 strategy was applied, 60% of clones were off-target and the rest were all heteroclones. Interestingly, most of the cells were edited successfully, but at least 60 % of the clones were heteroclones, when the CRISPR/Cas9-HDR strategy was employed. Our results clearly showed that the emergence of heteroclone seems inevitable regardless of the strategies used for editing BY4742 ade2. Given the characteristics of BY4742 defective in ade2 showing red on the YPD plate, we attempted to build an efficient yeast gene editing strategy, in which the CRISPR/Cas9 combines homology-mediated repair template carrying an ade2 expression cassette, BY4742(ade2Δ0) as the start strain. We used this strategy to successfully achieve 100 % knockout efficiency of trp1, indicating that technical challenges of how to easily screen out pure knockout clones without color phenotype have been solved. Our data showed in this study not only establishes an efficient yeast gene knockout strategy with dual auxotrophy coupled red labeling but also provides new ideas and references for the knockout of target genes in the monokaryotic mycelium of macrofungi.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Recombinación Homóloga , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Edición Génica/métodos , Sistemas CRISPR-Cas/genética , Recombinación Homóloga/genética , Genoma Fúngico/genética , Técnicas de Inactivación de Genes/métodos , Proteínas de Saccharomyces cerevisiae/genética
7.
Mol Phylogenet Evol ; 196: 108084, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38688440

RESUMEN

The tribe Collabieae (Epidendroideae, Orchidaceae) comprises approximately 500 species. Generic delimitation within Collabieae are confusing and phylogenetic interrelationships within the Collabieae have not been well resolved. Plastid genomes and nuclear internal transcribed spacer (ITS) sequences were used to estimate the phylogenetic relationships, ancestral ranges, and diversification rates of Collabieae. The results showed that Collabieae was subdivided into nine clades with high support. We proposed to combine Ancistrochilus and Pachystoma into Spathoglottis, merge Collabium and Chrysoglossum into Diglyphosa, and separate Pilophyllum and Hancockia as distinctive genera. The diversification of the nine clades of Collabieae might be associated with the uplift of the Himalayas during the Late Oligocene/Early Miocene. The enhanced East Asian summer monsoon in the Late Miocene may have promoted the rapid diversification of Collabieae at a sustained high diversification rate. The increased size of terrestrial pseudobulbs may be one of the drivers of Collabieae diversification. Our results suggest that the establishment and development of evergreen broadleaved forests facilitated the diversification of Collabieae.


Asunto(s)
Orchidaceae , Filogenia , Orchidaceae/genética , Orchidaceae/clasificación , Bosques , Genoma de Plastidios/genética , Filogeografía , ADN Espaciador Ribosómico/genética , Análisis de Secuencia de ADN , Asia , ADN de Plantas/genética
8.
Blood ; 139(21): 3181-3193, 2022 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-35040907

RESUMEN

Anemia of inflammation, also known as anemia of chronic disease, is refractory to erythropoietin (EPO) treatment, but the mechanisms underlying the EPO refractory state are unclear. Here, we demonstrate that high mobility group box-1 protein (HMGB1), a damage-associated molecular pattern molecule recently implicated in anemia development during sepsis, leads to reduced expansion and increased death of EPO-sensitive erythroid precursors in human models of erythropoiesis. HMGB1 significantly attenuates EPO-mediated phosphorylation of the Janus kinase 2/STAT5 and mTOR signaling pathways. Genetic ablation of receptor for advanced glycation end products, the only known HMGB1 receptor expressed by erythroid precursors, does not rescue the deleterious effects of HMGB1 on EPO signaling, either in human or murine precursors. Furthermore, surface plasmon resonance studies highlight the ability of HMGB1 to interfere with the binding between EPO and the EPOR. Administration of a monoclonal anti-HMGB1 antibody after sepsis onset in mice partially restores EPO signaling in vivo. Thus, HMGB1-mediated restriction of EPO signaling contributes to the chronic phase of anemia of inflammation.


Asunto(s)
Anemia , Eritropoyetina , Proteína HMGB1 , Sepsis , Anemia/genética , Animales , Eritropoyesis/genética , Eritropoyetina/metabolismo , Inflamación , Ratones , Receptores de Eritropoyetina/metabolismo , Sepsis/complicaciones
9.
J Neurol Neurosurg Psychiatry ; 95(10): 902-911, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-38503484

RESUMEN

BACKGROUND: This study aimed to investigate the efficacy of circuits-based paired associative stimulation (PAS) in adults with amnestic mild cognitive impairment (aMCI). METHODS: We conducted a parallel-group, randomised, controlled clinical trial. Initially, a cohort of healthy subjects was recruited to establish the cortical-hippocampal circuits by tracking white matter fibre connections using diffusion tensor imaging. Subsequently, patients diagnosed with aMCI, matched for age and education, were randomly allocated in a 1:1 ratio to undergo a 2-week intervention, either circuit-based PAS or sham PAS. Additionally, we explored the relationship between changes in cognitive performance and the functional connectivity (FC) of cortical-hippocampal circuits. RESULTS: FCs between hippocampus and precuneus and between hippocampus and superior frontal gyrus (orbital part) were most closely associated with the Auditory Verbal Learning Test (AVLT)_N5 score in 42 aMCI patients, thus designated as target circuits. The AVLT_N5 score improved from 2.43 (1.43) to 5.29 (1.98) in the circuit-based PAS group, compared with 2.52 (1.44) to 3.86 (2.39) in the sham PAS group (p=0.003; Cohen's d=0.97). A significant decrease was noted in FC between the left hippocampus and left precuneus in the circuit-based PAS group from baseline to postintervention (p=0.013). Using a generalised linear model, significant group×FC interaction effects for the improvements in AVLT_N5 scores were found within the circuit-based PAS group (B=3.4, p=0.017). CONCLUSIONS: Circuit-based PAS effectively enhances long-term delayed recall in adults diagnosed with aMCI, which includes individuals aged 50-80 years. This enhancement is potentially linked to the decreased functional connectivity between the left hippocampus and left precuneus. TRIAL REGISTRATION NUMBER: ChiCTR2100053315; Chinese Clinical Trial Registry.


Asunto(s)
Amnesia , Disfunción Cognitiva , Hipocampo , Recuerdo Mental , Humanos , Disfunción Cognitiva/fisiopatología , Disfunción Cognitiva/terapia , Masculino , Femenino , Anciano , Hipocampo/diagnóstico por imagen , Hipocampo/fisiopatología , Recuerdo Mental/fisiología , Amnesia/fisiopatología , Amnesia/diagnóstico por imagen , Amnesia/terapia , Imagen de Difusión Tensora , Persona de Mediana Edad , Pruebas Neuropsicológicas
10.
Exp Physiol ; 109(4): 524-534, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38213082

RESUMEN

Hindlimb ischaemia-reperfusion (IR) is among the most prominent pathophysiological conditions observed in peripheral artery disease (PAD). An exaggerated arterial blood pressure (BP) response during exercise is associated with an elevated risk of cardiovascular events in individuals with PAD. However, the precise mechanisms leading to this exaggerated BP response are poorly elucidated. The P2X3 signalling pathway, which plays a key role in modifying the exercise pressor reflex (EPR), is the focus of the present study. We determined the regulatory role of P2X3 on the EPR in a rat model of hindlimb IR. In vivo and in vitro approaches were used to determine the expression and functions of P2X3 in muscle afferent nerves and EPR in IR rats. We found that in IR rats there was (1) upregulation of P2X3 protein expression in the L4-6 dorsal root ganglia (DRG); (2) amplified P2X currents in isolated isolectin B4 (IB4)-positive muscle DRG neurons; and (3) amplification of the P2X-mediated BP response. We further verified that both A-317491 and siRNA knockdown of P2X3 significantly decreased the activity of P2X currents in isolated muscle DRG neurons. Moreover, inhibition of muscle afferents' P2X3 receptor using A-317491 was observed to alleviate the exaggerated BP response induced by static muscle contraction and P2X-induced BP response by α,ß-methylene ATP injection. P2X3 signalling pathway activity is amplified in muscle afferent DRG neurons in regulating the EPR following hindlimb IR.


Asunto(s)
Ganglios Espinales , Neuronas Aferentes , Fenoles , Compuestos Policíclicos , Ratas , Animales , Ganglios Espinales/metabolismo , Ratas Sprague-Dawley , Neuronas Aferentes/fisiología , Reflejo , Neuronas/metabolismo , Músculo Esquelético/metabolismo , Isquemia/metabolismo , Miembro Posterior/metabolismo , Receptores Purinérgicos P2X3/metabolismo
11.
Immunity ; 43(4): 764-75, 2015 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-26453377

RESUMEN

Sheep red blood cells (SRBCs) have long been used as a model antigen for eliciting systemic immune responses, yet the basis for their adjuvant activity has been unknown. Here, we show that SRBCs failed to engage the inhibitory mouse SIRPα receptor on splenic CD4(+) dendritic cells (DCs), and this failure led to DC activation. Removal of the SIRPα ligand, CD47, from self-RBCs was sufficient to convert them into an adjuvant for adaptive immune responses. DC capture of Cd47(-/-) RBCs and DC activation occurred within minutes in a Src-family-kinase- and CD18-integrin-dependent manner. These findings provide an explanation for the adjuvant mechanism of SRBCs and reveal that splenic DCs survey blood cells for missing self-CD47, a process that might contribute to detecting and mounting immune responses against pathogen-infected RBCs.


Asunto(s)
Inmunidad Adaptativa , Antígeno CD47/sangre , Células Dendríticas/inmunología , Eritrocitos/inmunología , Receptores Inmunológicos/inmunología , Autotolerancia/inmunología , Bazo/inmunología , Adyuvantes Inmunológicos , Animales , Secuencia de Bases , Antígenos CD18/fisiología , Antígenos CD4/análisis , Antígeno CD47/inmunología , Movimiento Celular , Células Dendríticas/metabolismo , Eritrocitos/química , Integrinas/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fagocitosis , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Quimera por Radiación , Receptores Inmunológicos/antagonistas & inhibidores , Ovinos , Organismos Libres de Patógenos Específicos , Subgrupos de Linfocitos T/inmunología , Familia-src Quinasas/deficiencia , Familia-src Quinasas/fisiología
12.
Langmuir ; 40(32): 16722-16730, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39093056

RESUMEN

Cervical cancer is among the most common malignant tumors in women. The development of rapid screening techniques plays an important role in early screening for cancer treatment. We have developed an HPV screening method, which effectively combines the high-efficiency nucleic acid enrichment of chitosan-modified filter paper and the rapid visual detectability of colorimetric LAMP, along with the enhancement of the tolerance ability of the pH-sensitive LAMP reagent to acidic original samples, making the detection of HPV 16/18 easy to carry out and reliable, which is helpful for the epidemiological prevention and control strategies of HPV-induced cancer. This technique can simultaneously exhibit the "in situ amplification" capability of chitosan-modified filter paper and the nontemperature cycle dependence of visual LAMP detection. Therefore, DNA extraction and amplification can be performed efficiently and quickly within a single reaction where all DNA is concentrated in the QF paper disc. By embedding amino-modified filter paper into the plastic chip, a simple and reliable disposable chip was prepared for rapid HPV16 and HPV18 detection from clinical endometrial samples, and the results were 100% consistent with clinical diagnosis. More importantly, even after the sample was diluted 100-fold, HPV16/18-infected cells could be accurately identified, showing the advantages of the system in early cancer screening. Moreover, for endometrial samples containing plenty of cells, the filter paper could be used to enrich cells by filtration, preventing the acidic fluid from impacting pH-induced colorimetric LAMP detection and realizing direct amplification for HPV identification without nucleic acid extraction. This easy-to-operate system that can analyze a wide range of samples will be suitable for routine on-site HPV screening, dramatically extending the applications and utility for rapid, near-patient nucleic acid testing.


Asunto(s)
Colorimetría , Papillomavirus Humano 16 , Papillomavirus Humano 18 , Técnicas de Amplificación de Ácido Nucleico , Papel , Humanos , Colorimetría/métodos , Papillomavirus Humano 18/genética , Papillomavirus Humano 18/aislamiento & purificación , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/aislamiento & purificación , Técnicas de Amplificación de Ácido Nucleico/métodos , Femenino , ADN Viral/análisis , ADN Viral/genética , Quitosano/química , Virus del Papiloma Humano
13.
Mol Cell Biochem ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38740701

RESUMEN

Pulmonary arterial hypertension (PAH) is a pathophysiological syndrome that is extremely difficult to manage, and there is currently no effective treatment. We want to elucidate the therapeutic effect of ethyl pyruvate (EP) on PAH and its possible mechanism. Pulmonary artery endothelial cells (PAECs) were cultured in conventional low-oxygen environments, and cellular proliferation was monitored after treatment with EP. Expression of p-PI3K/Akt, LC3-II, and Beclin-1 was detected by Western blot. After hyperkinetic PAH rabbits' models were treated with EP, hemodynamic data were collected. Right ventricular hypertrophy and pulmonary vascular remodeling were evaluated. Expression of p-PI3K/Akt, LC3-II, and Beclin-1 protein was also detected after using autophagy inhibitor and agonists. We found that EP could inhibit PAECs proliferation. After EP treatment, expression of p-PI3K/Akt was upregulated in vitro and in vivo. LC3-II and Beclin-1 were inhibited and their expression was lower after autophagy inhibitor was given, while after administration of autophagy agonists, their expression was higher than that in the EP alone group. Besides, EP attenuated PAH, and right ventricular hypertrophy and pulmonary vascular remodeling were also reversed. EP can reduce PAH and reverse vascular remodeling which is associated with inhibition of autophagy in PAECs based on PI3K-Akt signaling pathway. The results of this study can provide surgical opportunities for patients with severe PAH caused by congenital heart disease in clinical cardiovascular surgery.

14.
Chem Rev ; 122(13): 11432-11473, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35537069

RESUMEN

Metal ions are ubiquitous in nature and play significant roles in assembling functional materials in fields spanning chemistry, biology, and materials science. Metal-phenolic materials are assembled from phenolic components in the presence of metal ions through the formation of metal-organic complexes. Alkali, alkali-earth, transition, and noble metal ions as well as metalloids interacting with phenolic building blocks have been widely exploited to generate diverse hybrid materials. Despite extensive studies on the synthesis of metal-phenolic materials, a comprehensive summary of how metal ions guide the assembly of phenolic compounds is lacking. A fundamental understanding of the roles of metal ions in metal-phenolic materials engineering will facilitate the assembly of materials with specific and functional properties. In this review, we focus on the diversity and function of metal ions in metal-phenolic material engineering and emerging applications. Specifically, we discuss the range of underlying interactions, including (i) cation-π, (ii) coordination, (iii) redox, and (iv) dynamic covalent interactions, and highlight the wide range of material properties resulting from these interactions. Applications (e.g., biological, catalytic, and environmental) and perspectives of metal-phenolic materials are also highlighted.


Asunto(s)
Complejos de Coordinación , Metales , Álcalis , Complejos de Coordinación/química , Iones , Ciencia de los Materiales , Metales/química , Fenoles
15.
Environ Sci Technol ; 58(9): 4381-4391, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38381810

RESUMEN

Organophosphate diesters (di-OPEs), as additives in industrial applications and/or transformation products of emerging environmental pollutants, such as organophosphate triesters (tri-OPEs), have been found in the environment and biological matrices. The metabolic fate of di-OPEs in biological media is of great significance for tracing the inherent and precursor toxicity variations. This is the first study to investigate the metabolism of a suite of di-OPEs by liver microsomes and to identify any metabolite of metabolizable di-OPEs in in vitro and in vivo samples. Of the 14 di-OPEs, 5 are significantly metabolizable, and their abundant metabolites with hydroxyl, carboxyl, dealkylated, carbonyl, and/or epoxide groups are tentatively identified. More than half of the di-OPEs are detectable in human serum and/or wild fish tissues, and dibenzyl phosphate (DBzP), bis(2,3-dibromopropyl) phosphate (BDBPP), and isopropyl diphenyl phosphate (ip-DPHP) are first reported at a detectable level in humans and wildlife. Using an in vitro assay and a known biotransformation rule-based integrated screening strategy, 2 and 10 suspected metabolite peaks of DEHP are found in human serum and wild fish samples, respectively, and are then identified as phase I and phase II metabolites of DEHP. This study provides a novel insight into fate and persistence of di-OPE and confirms the presence of di-OPE metabolites in humans and wildlife.


Asunto(s)
Dietilhexil Ftalato , Retardadores de Llama , Animales , Humanos , Organofosfatos , Retardadores de Llama/análisis , Ésteres , Biotransformación , Fosfatos , China , Monitoreo del Ambiente
16.
Environ Sci Technol ; 58(41): 18098-18108, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39367834

RESUMEN

There is growing evidence of the frequent detection of tire rubber-derived contaminants p-phenylenediamine-derived quinones (PPD-Qs) (e.g., highly toxic N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine quinone (6PPD-Q)) in the environment and biota and the adverse impact on organisms. Hence, a better understanding of their biotransformation/metabolism in humans is essential. However, relevant data are lacking owing to recent discoveries. Herein, the biotransformation patterns of 6PPD-Q and other five commonly detected PPD-Qs were characterized via combined in vitro assay and maternal cord blood screening monitoring. Rapid metabolism was found for each PPD-Q incubated with human liver S9 fraction and microsomes, resulting in the formation of abundant phase I and phase II metabolites. The subsequent screening for potential PPD-Q metabolites in blood samples showed the presence of suspect metabolites. Three detected metabolites were confirmed by matching the mass spectra and retention times of in vitro metabolites. N-Dealkylated, carboxy, carbonyl, and reductive metabolites and glucose, cysteine, and methionine conjugates were observed for the first time. The semiquantitative concentrations of metabolites were higher than those of the parent PPD-Qs, and several metabolites such as carboxy products were proposed as candidate biomarkers of PPD-Q exposure to humans. 6PPD-Q and N,N'-diphenyl-p-phenylenediamine quinone were detected in maternal and/or cord whole blood samples for the first time. This study holds great importance in elucidating the potential risks and health effects of PPD-Qs.


Asunto(s)
Biomarcadores , Fenilendiaminas , Goma , Humanos , Fenilendiaminas/metabolismo , Quinonas/metabolismo , Femenino
17.
J Phys Chem A ; 128(41): 8996-9014, 2024 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-39360616

RESUMEN

n-Pentanol is acknowledged as a prospective alternative and a supplement to traditional fossil fuels. H-abstraction reaction assumes a pivotal role in initiating the chain reaction during n-pentanol combustion. To investigate the oxidation characteristics of n-pentanol, the composite quantum chemical methods CBS-QB3 and G4 are employed to obtain thermochemical and kinetic parameters in the H-abstraction reaction of n-pentanol. The calculated isobaric heat capacity provides accurate predictions of the experimental results. Branching ratios underscore that H-abstraction at the Cα site serves as the primary channel between n-pentanol and H/CH3/È®H2. For the reaction between n-pentanol and È®H, the Cß site emerges as the most favorable channel due to the significant variational effect. The overall rate coefficient for H-abstraction from n-pentanol by È®H radicals is expressed as k = 3565.11 × T2.93 exp (1465.44/T) (cm3 mol-1 s-1), and the data obtained at the CBS-QB3 level demonstrate good agreement with experimental observations. Furthermore, the original model is modified based on current results, and the improved model demonstrates superior predictive capabilities for jet-stirred reactor (JSR) data and ignition delay times. Reaction path and sensitivity analyses are employed to identify fuel consumption pathways and critical reactions in the combustion of n-pentanol.

18.
Nature ; 554(7691): 234-238, 2018 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-29420476

RESUMEN

High species diversity may result from recent rapid speciation in a 'cradle' and/or the gradual accumulation and preservation of species over time in a 'museum'. China harbours nearly 10% of angiosperm species worldwide and has long been considered as both a museum, owing to the presence of many species with hypothesized ancient origins, and a cradle, as many lineages have originated as recent topographic changes and climatic shifts-such as the formation of the Qinghai-Tibetan Plateau and the development of the monsoon-provided new habitats that promoted remarkable radiation. However, no detailed phylogenetic study has addressed when and how the major components of the Chinese angiosperm flora assembled to form the present-day vegetation. Here we investigate the spatio-temporal divergence patterns of the Chinese flora using a dated phylogeny of 92% of the angiosperm genera for the region, a nearly complete species-level tree comprising 26,978 species and detailed spatial distribution data. We found that 66% of the angiosperm genera in China did not originate until early in the Miocene epoch (23 million years ago (Mya)). The flora of eastern China bears a signature of older divergence (mean divergence times of 22.04-25.39 Mya), phylogenetic overdispersion (spatial co-occurrence of distant relatives) and higher phylogenetic diversity. In western China, the flora shows more recent divergence (mean divergence times of 15.29-18.86 Mya), pronounced phylogenetic clustering (co-occurrence of close relatives) and lower phylogenetic diversity. Analyses of species-level phylogenetic diversity using simulated branch lengths yielded results similar to genus-level patterns. Our analyses indicate that eastern China represents a floristic museum, and western China an evolutionary cradle, for herbaceous genera; eastern China has served as both a museum and a cradle for woody genera. These results identify areas of high species richness and phylogenetic diversity, and provide a foundation on which to build conservation efforts in China.


Asunto(s)
Biodiversidad , Magnoliopsida/clasificación , Filogenia , China , Conservación de los Recursos Naturales/métodos , Evolución Molecular , Mapeo Geográfico , Análisis de Regresión , Análisis Espacio-Temporal
19.
Environ Res ; 258: 119406, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38871277

RESUMEN

To carry out the diagnosis and evaluation of the ecosystem health in Yuxi three-lake watershed, this paper presents the changing trend of its health state, and predicts the future development. This also provides ideas for maintaining the regional ecosystem health, and then gradually improves the ecological environment quality. Taking Fuxian Lake, Qilu Lake and Xingyun Lake (the three-lake watershed) in Yuxi City, Yunnan Province, Southwest China as the research object, a model combining pressure-state-response and kernel density estimation (PSR-KDE) adopts to diagnose and evaluate the ecosystem health of the "three lake" watershed from 2010 to 2020, and the distribution map of ecosystem health index has obtained by the evaluation indexes integration based on GIS spatial analysis. Hence, the evaluation results have visualized on the map. The results show that: The distribution of ecosystem health index in the study area was 0.1530-0.7045 in 2010, 0.2056-0.7512 in 2015, and 0.2248-0.7662 in 2020. 0.12% was in the pathological area in 2010. After 2015, the pathological condition of ecosystem health has completely solved, and the proportion of unhealthy ecosystems was 11.95% in 2010, 7.38% in 2015, and 5.97% in 2020. The ecosystem health index of the study region was 0.5523 in 2010, 0.5807 in 2015, and 0.5815 in 2020, it indicates that the ecosystem was in a sub-health state. From 2010 to 2020, the ecosystem health around Qilu Lake was the most worrying, followed by the northwest of Fuxian Lake and the northern and southern regions of Xingyun Lake. The ecosystem health of the three-lake watershed showed significant improvement from 2010 to 2020. The study ecosystem health assessment and early warning in the three-lake watershed is significant to the ecological environment protection and management of the plateau lake basin, the restoration of the territorial space ecology and the economic development of the surrounding area.


Asunto(s)
Ecosistema , Monitoreo del Ambiente , Lagos , China , Monitoreo del Ambiente/métodos , Modelos Teóricos
20.
J Comput Assist Tomogr ; 48(2): 303-310, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37654056

RESUMEN

INTRODUCTION: In glioma patients that have undergone surgical tumor resection, the ability to reliably distinguish between pseudoprogression (PsP) and a recurrent tumor (RT) is of key clinical importance. Accordingly, this meta-analysis evaluated the utility of dynamic susceptibility contrast-enhanced perfusion-weighted imaging as a means of distinguishing between PsP and RT when analyzing patients with high-grade glioma. MATERIALS AND METHODS: The PubMed, Web of Science, and Wanfang databases were searched for relevant studies. Pooled analyses of sensitivity, specificity, positive likelihood ratio (PLR), and negative likelihood ratio (NLR) values were conducted, after which the area under the curve (AUC) for summary receiver operating characteristic curves was computed. RESULTS: This meta-analysis ultimately included 21 studies enrolling 879 patients with 888 lesions. Cerebral blood volume-associated diagnostic results were reported in 20 of the analyzed studies, and the respective pooled sensitivity, specificity, PLR, and NLR values were 86% (95% confidence interval [CI], 0.81-0.89), 83% (95% CI, 0.77-0.87), 4.94 (95% CI, 3.61-6.75), and 0.18 (95% CI, 0.13-0.23) for these 20 studies. The corresponding AUC value was 0.91 (95% CI, 0.88-0.93), and the publication bias risk was low ( P = 0.976). Cerebral blood flow-related diagnostic results were additionally reported in 6 of the analyzed studies, with respective pooled sensitivity, specificity, PLR, and NLR values of 85% (95% CI, 0.78-0.90), 85% (95% CI, 0.76-0.91), 5.54 (95% CI, 3.40-9.01), and 0.18 (95% CI, 0.12-0.26). The corresponding AUC value was 0.92 (95% CI, 0.89-0.94), and the publication bias risk was low ( P = 0.373). CONCLUSIONS: The present meta-analysis results suggest that dynamic susceptibility contrast-enhanced perfusion-weighted imaging represents an effective diagnostic approach to distinguishing between PsP and RT in high-grade glioma patients.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Sensibilidad y Especificidad , Glioma/diagnóstico por imagen , Glioma/patología , Angiografía por Resonancia Magnética , Perfusión
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