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1.
Sci Adv ; 10(33): eadp4906, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39141724

RESUMEN

High-voltage phase transition constitutes the major barrier to accessing high energy density in layered cathodes. However, questions remain regarding the origin of phase transition, because the interlayer weak bonding features cannot get an accurate description by experiments. Here, we determined van der Waals (vdW) interaction (vdWi) in LixCoO2 via visualizing its electron density, elucidating the origin of O3─O1 phase transition. The charge around oxygen is distorted by the increasing Co─O covalency. The charge distortion causes the difference of vdW gap between O3 and O1 phases, verified by a gap corrected vdW equation. In a high charging state, excessive covalency breaks the vdW gap balance, driving the O3 phase toward a stable O1 one. This interpretation of vdWi-dominated phase transition can be applied to other layered materials, as shown by a map regarding degree of covalence. Last, we introduce the cationic potential to provide a solution for designing high-voltage layered cathodes.

2.
Heliyon ; 10(13): e33938, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39071710

RESUMEN

Purpose: Invasive micropapillary carcinoma (IMPC) of the breast has a high propensity for lymphovascular invasion and axillary lymph node metastasis and displays an 'inside-out' growth pattern, but the molecular mechanism of invasion, metastasis and cell polarity reversal in IMPC is unclear. Methods: and Patients: Cell growth curves, tumor sphere formation assays, transwell assays, mouse xenograft model and immunofluorescence were evaluated to investigate the effects of miR-30c and MTDH. Dual luciferase reporter assays was performed to confirm that the MTDH (metadherin) 3'UTR bound to miR-30c. MiRNA in situ hybridization (ISH) and immunohistochemistry (IHC) were carried out on IMPC patient tissues for miR-30c and MTDH expression, respectively. Results: We found miR-30c as a tumor suppressor gene in cell proliferation, metastasis and polarity reversal of IMPC. Overexpression of miR-30c inhibited cell growth and metastasis in vitro and in vivo. MiR-30c could directly target the MTDH 3'UTR. MiR-30c overexpression inhibited breast cancer cell proliferation, invasion and metastasis by targeting MTDH. Moreover, miR-30c/MTDH axis could also regulate cell polarity reversal of IMPC. By ISH and IHC analyses, miR-30c and MTDH were significantly correlated with tumor size, lymph nodule status and tumor grade, the 'inside-out' growth pattern, overall survival (OS) and disease-free survival (DFS) in IMPC patients. Conclusions: Overall, miR-30c/MTDH axis was responsible for tumor proliferation, metastasis and polarity reversal. It may provide promising therapeutic targets and prognostic biomarkers for patients with IMPC.

3.
BMC Cardiovasc Disord ; 24(1): 360, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39009987

RESUMEN

BACKGROUND: The atherogenic index of plasma (AIP) is considered an independent risk factor for coronary artery disease (CAD). The present study investigated whether AIP correlates with the formation of coronary collateral circulation (CCC) in CAD patients with chronic total occlusion (CTO). METHODS: This retrospective study included 1093 CAD patients with CTO confirmed by coronary angiography from January 2020 to December 2020 at Beijing Anzhen Hospital. Based on the Rentrop scoring system, the patients were divided into the good CCC group and the poor CCC group. AIP was calculated by log (triglyceride/high-density lipoprotein cholesterol). Meanwhile, the study population was further divided into four groups according to the quartiles of AIP. RESULTS: Patients in the poor CCC group exhibited significantly higher AIP compared to those in the good CCC group (0.31 ± 0.27 vs. 0.14 ± 0.24, p < 0.001). Multivariate logistic regression analysis revealed an independent association between AIP and poor CCC, regardless of whether AIP was treated as a continuous or categorical variable (p < 0.001), after adjusting for confounding factors. Besides, this association remained consistent across most subgroups. The incorporation of AIP into the baseline model significantly enhanced the accuracy of identifying poor CCC [area under the curve (AUC): baseline model, 0.661 vs. baseline model + AIP, 0.721, p for comparison < 0.001]. CONCLUSIONS: Elevated AIP is independently associated with an increased risk of poor CCC in CAD patients with CTO, and AIP may improve the ability to identify poor CCC in clinical practice.


Asunto(s)
Biomarcadores , Circulación Colateral , Angiografía Coronaria , Circulación Coronaria , Oclusión Coronaria , Humanos , Masculino , Oclusión Coronaria/fisiopatología , Oclusión Coronaria/diagnóstico por imagen , Oclusión Coronaria/sangre , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Anciano , Enfermedad Crónica , Biomarcadores/sangre , Medición de Riesgo , Enfermedad de la Arteria Coronaria/fisiopatología , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/diagnóstico , Valor Predictivo de las Pruebas , Triglicéridos/sangre , HDL-Colesterol/sangre , Factores de Riesgo , Pronóstico
4.
J Clin Oncol ; : JCO2400447, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39052972

RESUMEN

PURPOSE: Validated and accurate prognostic testing is critical for precision medicine in uveal melanoma (UM). Our aims were to (1) prospectively validate an integrated prognostic classifier combining a 15-gene expression profile (15-GEP) and PRAME RNA expression and (2) identify clinical variables that enhance the prognostic accuracy of the 15-GEP/PRAME classifier. MATERIALS AND METHODS: This study included 1,577 patients with UM of the choroid and/or ciliary body who were enrolled in the Collaborative Ocular Oncology Group Study Number 2 (COOG2) and prospectively monitored across 26 North American centers. Test results for 15-GEP (class 1 or class 2) and PRAME expression status (negative or positive) were available for all patients. The primary end point was metastasis-free survival (MFS). RESULTS: 15-GEP was class 1 in 1,082 (68.6%) and class 2 in 495 (31.4%) patients. PRAME status was negative in 1,106 (70.1%) and positive in 471 (29.9%) patients. Five-year MFS was 95.6% (95% CI, 93.9 to 97.4) for class 1/PRAME(-), 80.6% (95% CI, 73.9 to 87.9) for class 1/PRAME(+), 58.3% (95% CI, 51.1 to 66.4) for class 2/PRAME(-), and 44.8% (95% CI, 37.9 to 52.8) for class 2/PRAME(+). By multivariable Cox proportional hazards analysis, 15-GEP was the most important independent predictor of MFS (hazard ratio [HR], 5.95 [95% CI, 4.43 to 7.99]; P < .001), followed by PRAME status (HR, 1.82 [95% CI, 1.42 to 2.33]; P < .001). The only clinical variable demonstrating additional prognostic value was tumor diameter. CONCLUSION: In the largest prospective multicenter prognostic biomarker study performed to date in UM to our knowledge, the COOG2 study validated the superior prognostic accuracy of the integrated 15-GEP/PRAME classifier over 15-GEP alone and clinical prognostic variables. Tumor diameter was found to be the only clinical variable to provide additional prognostic information. This prognostic classifier provides an advanced resource for risk-adjusted metastatic surveillance and adjuvant trial stratification in patients with UM.

5.
Natl Sci Rev ; 11(7): nwae175, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38883296

RESUMEN

Anisotropy is a significant and prevalent characteristic of materials, conferring orientation-dependent properties, meaning that the creation of original symmetry enables key functionality that is not found in nature. Even with the advancements in atomic machining, synthesis of separated symmetry in different directions within a single structure remains an extraordinary challenge. Here, we successfully fabricate NiS ultrafine nanorods with separated symmetry along two directions. The atomic structure of the nanorod exhibits rotational symmetry in the radial direction, while its axial direction is characterized by divergent translational symmetry, surpassing the conventional crystalline structures known to date. It does not fit the traditional description of the space group and the point group in three dimensions, so we define it as a new structure in which translational symmetry and rotational symmetry are separated. Further corroborating the atomic symmetric separation in the electronic structure, we observed the combination of stripe and vortex magnetic domains in a single nanorod with different directions, in accordance with the atomic structure. The manipulation of nanostructure at the atomic level introduces a novel approach to regulate new properties finely, leading to the proposal of new nanotechnology mechanisms.

6.
ACS Synth Biol ; 13(6): 1831-1841, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38863339

RESUMEN

Antimicrobial resistance poses a significant global challenge, demanding innovative approaches, such as the CRISPR-Cas-mediated resistance plasmid or gene-curing system, to effectively combat this urgent crisis. To enable successful curing of antimicrobial genes or plasmids through CRISPR-Cas technology, the development of an efficient broad-host-range delivery system is paramount. In this study, we have successfully designed and constructed a novel functional gene delivery plasmid, pQ-mini, utilizing the backbone of a broad-host-range Inc.Q plasmid. Moreover, we have integrated the CRISPR-Cas12f system into the pQ-mini plasmid to enable gene-curing in broad-host of bacteria. Our findings demonstrate that pQ-mini facilitates the highly efficient transfer of genetic elements to diverse bacteria, particularly in various species in the order of Enterobacterales, exhibiting a broader host range and superior conjugation efficiency compared to the commonly used pMB1-like plasmid. Notably, pQ-mini effectively delivers the CRISPR-Cas12f system to antimicrobial-resistant strains, resulting in remarkable curing efficiencies for plasmid-borne mcr-1 or blaKPC genes that are comparable to those achieved by the previously reported pCasCure system. In conclusion, our study successfully establishes and optimizes pQ-mini as a broad-host-range functional gene delivery vector. Furthermore, in combination with the CRISPR-Cas system, pQ-mini demonstrates its potential for broad-host delivery, highlighting its promising role as a novel antimicrobial tool against the growing threat of antimicrobial resistance.


Asunto(s)
Antibacterianos , Sistemas CRISPR-Cas , Bacterias Gramnegativas , Plásmidos , Sistemas CRISPR-Cas/genética , Plásmidos/genética , Bacterias Gramnegativas/genética , Bacterias Gramnegativas/efectos de los fármacos , Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Técnicas de Transferencia de Gen , Edición Génica/métodos
7.
Microbiol Spectr ; 12(8): e0430723, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-38916339

RESUMEN

Mycophenolate mofetil (MMF) is commonly utilized for the treatment of neuromyelitis optica spectrum disorders (NMOSD). However, a subset of patients experience significant gastrointestinal (GI) adverse effects following MMF administration. The present study aims to elucidate the underlying mechanisms of MMF-induced GI toxicity in NMOSD. Utilizing a vancomycin-treated mouse model, we compiled a comprehensive data set to investigate the microbiome and metabolome in the GI tract to elucidate the mechanisms of MMF GI toxicity. Furthermore, we enrolled 17 female NMOSD patients receiving MMF, who were stratified into non-diarrhea NMOSD and diarrhea NMOSD (DNM) groups, in addition to 12 healthy controls. The gut microbiota of stool samples was analyzed using 16S rRNA gene sequencing. Vancomycin administration prevented weight loss and tissue injury caused by MMF, affecting colon metabolomes and microbiomes. Bacterial ß-glucuronidase from Bacteroidetes and Firmicutes was linked to intestinal tissue damage. The DNM group showed higher alpha diversity and increased levels of Firmicutes and Proteobacteria. The ß-glucuronidase produced by Firmicutes may be important in causing gastrointestinal side effects from MMF in NMOSD treatment, providing useful information for future research on MMF. IMPORTANCE: Neuromyelitis optica spectrum disorder (NMOSD) patients frequently endure severe consequences like paralysis and blindness. Mycophenolate mofetil (MMF) effectively addresses these issues, but its usage is hindered by gastrointestinal (GI) complications. Through uncovering the intricate interplay among MMF, gut microbiota, and metabolic pathways, this study identifies specific gut bacteria responsible for metabolizing MMF into a potentially harmful form, thus contributing to GI side effects. These findings not only deepen our comprehension of MMF toxicity but also propose potential strategies, such as inhibiting these bacteria, to mitigate these adverse effects. This insight holds broader implications for minimizing complications in NMOSD patients undergoing MMF therapy.


Asunto(s)
Modelos Animales de Enfermedad , Microbioma Gastrointestinal , Ácido Micofenólico , Neuromielitis Óptica , Ácido Micofenólico/efectos adversos , Ácido Micofenólico/uso terapéutico , Neuromielitis Óptica/tratamiento farmacológico , Neuromielitis Óptica/microbiología , Humanos , Animales , Ratones , Microbioma Gastrointestinal/efectos de los fármacos , Femenino , Adulto , Persona de Mediana Edad , Vancomicina/efectos adversos , ARN Ribosómico 16S/genética , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/microbiología , Diarrea/inducido químicamente , Diarrea/microbiología , Masculino , Enfermedades Gastrointestinales/inducido químicamente , Heces/microbiología , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/clasificación
8.
Nano Lett ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38842462

RESUMEN

The aggravated mechanical and structural degradation of layered oxide cathode materials upon high-voltage charging invariably causes fast capacity fading, but the underlying degradation mechanisms remain elusive. Here we report a new type of mechanical degradation through the formation of a kink band in a Mg and Ti co-doped LiCoO2 cathode charged to 4.55 V (vs Li/Li+). The local stress accommodated by the kink band can impede crack propagation, improving the structural integrity in a highly delithiated state. Additionally, machine-learning-aided atomic-resolution imaging reveals that the formation of kink bands is often accompanied by the transformation from the O3 to O1 phase, which is energetically favorable as demonstrated by first-principles calculations. Our results provide new insights into the mechanical degradation mechanism of high-voltage LiCoO2 and the coupling between electrochemically triggered mechanical failures and structural transition, which may provide valuable guidance for enhancing the electrochemical performance of high-voltage layered oxide cathode materials for lithium-ion batteries.

9.
Nat Commun ; 15(1): 3954, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38729958

RESUMEN

Defense-associated sirtuin 2 (DSR2) systems are widely distributed across prokaryotic genomes, providing robust protection against phage infection. DSR2 recognizes phage tail tube proteins and induces abortive infection by depleting intracellular NAD+, a process that is counteracted by another phage-encoded protein, DSR Anti Defense 1 (DSAD1). Here, we present cryo-EM structures of Bacillus subtilis DSR2 in its apo, Tube-bound, and DSAD1-bound states. DSR2 assembles into an elongated tetramer, with four NADase catalytic modules clustered in the center and the regulatory-sensing modules distributed at four distal corners. Interestingly, monomeric Tube protein, rather than its oligomeric states, docks at each corner of the DSR2 tetramer to form a 4:4 DSR2-Tube assembly, which is essential for DSR2 NADase activity. DSAD1 competes with Tube for binding to DSR2 by occupying an overlapping region, thereby inhibiting DSR2 immunity. Thus, our results provide important insights into the assembly, activation and inhibition of the DSR2 anti-phage defense system.


Asunto(s)
Bacillus subtilis , Proteínas Bacterianas , Bacteriófagos , Microscopía por Crioelectrón , Bacillus subtilis/inmunología , Bacillus subtilis/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/química , Proteínas Bacterianas/inmunología , Bacteriófagos/genética , Bacteriófagos/inmunología , Evasión Inmune , Sirtuinas/metabolismo , Sirtuinas/genética , Proteínas Virales/metabolismo , Proteínas Virales/inmunología , Proteínas Virales/química , Proteínas Virales/genética , Unión Proteica , Modelos Moleculares , NAD/metabolismo
10.
Nat Mater ; 23(8): 1077-1084, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38589541

RESUMEN

Robust ferroelectricity in nanoscale fluorite oxide-based thin films enables promising applications in silicon-compatible non-volatile memories and logic devices. However, the polar orthorhombic (O) phase of fluorite oxides is a metastable phase that is prone to transforming into the ground-state non-polar monoclinic (M) phase, leading to macroscopic ferroelectric degradation. Here we investigate the reversibility of the O-M phase transition in ZrO2 nanocrystals via in situ visualization of the martensitic transformation at the atomic scale. We reveal that the reversible shear deformation pathway from the O phase to the monoclinic-like (M') state, a compressive-strained M phase, is protected by 90° ferroelectric-ferroelastic switching. Nevertheless, as the M' state gradually accumulates localized strain, a critical tensile strain can pin the ferroelastic domain, resulting in an irreversible M'-M strain relaxation and the loss of ferroelectricity. These findings demonstrate the key role of ferroelastic switching in the reversibility of phase transition and also provide a tensile-strain threshold for stabilizing the metastable ferroelectric phase in fluorite oxide thin films.

11.
RSC Adv ; 14(15): 10714-10725, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38567330

RESUMEN

Conventional Au nanomaterial synthesis typically necessitates the involvement of extensive surfactants and reducing agents, leading to a certain amount of chemical waste and biological toxicity. In this study, we innovatively employed ultra-small graphene oxide as a reducing agent and surfactant for the in situ generation of small Au nanoparticles under ultraviolet irradiation (UV) at ambient conditions. After ultra-small GO-Au seeds were successfully synthesized, we fabricated small star-like Au nanoparticles on the surface of GO, in which GO effectively prevented Austar from aggregation. To further use GO-Austar for cancer PTT therapy, through the modification of reduced human serum albumin-folic acid conjugate (rHSA-FA) and loading IR780, the final probe GO-Austar@rHSA-FA@IR780 was prepared. The prepared probe showed excellent biocompatibility and superb phototoxicity towards MGC-803 cells in vitro. In vivo, the final probe dramatically increased tumor temperature up to 58.6 °C after 5 minutes of irradiation by an 808 nm laser, significantly inhibiting tumor growth and nearly eradicating subcutaneous tumors in mice. This research provides a novel and simple method for the synthesis of GO-Au nanocomposites, showcasing significant potential in biological applications.

12.
Talanta ; 273: 125868, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38458085

RESUMEN

Magnetic nanoparticle (MNP)-based immunochromatographic tests (ICTs) display long-term stability and an enhanced capability for multiplex biomarker detection, surpassing conventional gold nanoparticles (AuNPs) and fluorescence-based ICTs. In this study, we innovatively developed zwitterionic silica-coated MNPs (MNP@Si-Zwit/COOH) with outstanding antifouling capabilities and effectively utilised them for the simultaneous identification of the nucleocapsid protein (N protein) of the severe acute respiratory syndrome coronavirus (SARS-CoV-2) and influenza A/B. The carboxyl-functionalised MNPs with 10% zwitterionic ligands (MNP@Si-Zwit 10/COOH) exhibited a wide linear dynamic detection range and the most pronounced signal-to-noise ratio when used as probes in the ICT. The relative limit of detection (LOD) values were achieved in 12 min by using a magnetic assay reader (MAR), with values of 0.0062 ng/mL for SARS-CoV-2 and 0.0051 and 0.0147 ng/mL, respectively, for the N protein of influenza A and influenza B. By integrating computer vision and deep learning to enhance the image processing of immunoassay results for multiplex detection, a classification accuracy in the range of 0.9672-0.9936 was achieved for evaluating the three proteins at concentrations of 0, 0.1, 1, and 10 ng/mL. The proposed MNP-based ICT for the multiplex diagnosis of biomarkers holds substantial promise for applications in both medical institutions and self-administered diagnostic settings.


Asunto(s)
Aprendizaje Profundo , Gripe Humana , Nanopartículas del Metal , Humanos , Oro/química , Nanopartículas del Metal/química , Gripe Humana/diagnóstico , Inmunoensayo/métodos , Biomarcadores , Fenómenos Magnéticos
13.
AIDS Behav ; 28(5): 1731-1740, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38361170

RESUMEN

Mental illness (MI) and substance use (SU) are highly prevalent among people with HIV (PWH) and impact care outcomes. The Substance Abuse and Mental Illness Symptoms Screener (SAMISS) is a validated screener for MI and SU, but it is unknown how screening results at entry to care correlate with subsequent HIV outcomes. This is a retrospective chart review of individuals newly diagnosed with HIV between 2016 and 2019 in a Southern US, safety-net clinic. Baseline demographics, HIV risk factors, socioeconomic variables, and SAMISS screening scores were collected. Outcomes included retention in care, achieving virologic suppression (VS), and continuous VS. Data analyses included stepwise Cox and logistic multivariate regression modeling. Among the 544 newly diagnosed PWH, mean age was 35, 76% were male, 46% non-Hispanic Black, 40% Hispanic/other. Overall, 35% screened positive for SU and 41% for MI. A positive SU (odds ratio (OR) 0.66, p = 0.04) or MI (OR 0.65, p = 0.03) SAMISS screening was associated with lower retention in care in univariate analysis, but was not statistically significant after adjusting for other variables. Positive SAMISS screening for SU and MI were both associated with reduced continuous VS in univariate and multivariate analyses (SU: adjusted OR (aOR) 0.67, p = 0.05; MI: aOR 0.66, p = 0.03). SAMISS is a useful tool for prospectively identifying individuals at risk for low retention in care and for not achieving sustained VS. Future interventions guided by SAMISS may improve HIV care continuum outcomes.


Asunto(s)
Continuidad de la Atención al Paciente , Infecciones por VIH , Tamizaje Masivo , Trastornos Mentales , Trastornos Relacionados con Sustancias , Humanos , Masculino , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/psicología , Adulto , Trastornos Relacionados con Sustancias/epidemiología , Estudios Retrospectivos , Trastornos Mentales/diagnóstico , Trastornos Mentales/epidemiología , Tamizaje Masivo/métodos , Persona de Mediana Edad , Factores de Riesgo , Retención en el Cuidado/estadística & datos numéricos , Estados Unidos/epidemiología
14.
J Int Assoc Provid AIDS Care ; 23: 23259582241228164, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38297512

RESUMEN

Rapid start of antiretroviral therapy (ART) has been associated with improvement in several HIV-related outcomes in clinical trials as well as demonstration projects, but how regional and contextual differences may affect the effectiveness of this intervention necessitates further study. In this study of a large, urban, Southern US clinic-based retrospective cohort, we identified 544 patients with a new diagnosis of HIV during 2016 to 2019 and compared HIV care continuum outcomes for the first 12 months of care before and after rapid start implementation. Kaplan-Meier time-to-event curves were used to summarize time to virologic suppression, and stepwise Cox, linear, and logistic regression models were used to create multivariate models to evaluate the association between rapid start and time to virologic suppression, medication adherence, and retention in care and sustained virologic suppression, respectively. We found that rapid start was significantly associated with improved medication adherence scores (+15.37 points, 95% confidence interval [CI] 9.36-21.39, P < .01) and retention in care (adjusted odds ratio = 1.51, 95% CI 1.05-2.19, P = .03). Time to virologic suppression (median 2.46 months before, 2.56 months after rapid start) and sustained virologic suppression were not associated with rapid start in our setting. Though rapid start was associated with improved medication adherence and retention in care, more support may be needed to achieve the same outcomes seen in other studies and sustained over the entire HIV care continuum, especially in settings with significant patient and systemic barriers to care such as unstable housing, lack of Medicaid expansion, and frequent coverage interruptions.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Humanos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Fármacos Anti-VIH/uso terapéutico , Estudios Retrospectivos , Carga Viral , Continuidad de la Atención al Paciente , Cumplimiento de la Medicación
15.
Int J Biol Macromol ; 264(Pt 1): 130145, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38382789

RESUMEN

Mycophenolate mofetil (MMF) is a viable therapeutic option against various immune disorders as a chemotherapeutic agent. Nevertheless, its application has been undermined by the gastrotoxic metabolites (mycophenolic acid glucuronide, MPAG) produced by microbiome-associated ß-glucuronidase (ßGUS). Therefore, controlling microbiota-produced ßGUS underlines the potential strategy to improve MMF efficacy by overcoming the dosage limitation. In this study, the octyl gallate (OG) was identified with promising inhibitory activity on hydrolysis of PNPG in our high throughput screening based on a chemical collection of approximately 2000 natural products. Furthermore, OG was also found to inhibit a broad spectrum of BGUSs, including mini-Loop1, Loop 2, mini-Loop 2, and mini-Loop1,2. The further in vivo experiments demonstrated that administration of 20 mg/kg OG resulted in predominant reduction in the activity of BGUSs while displayed no impact on the overall fecal microbiome in mice. Furthermore, in the MMF-induced colitis model, the administration of OG at a dosage of 20 mg/kg effectively mitigated the gastrointestinal toxicity, and systematically reverted the colitis phenotypes. These findings indicate that the OG holds promising clinical potential for the prevention of MMF-induced gastrointestinal toxicity by inhibition of BGUSs and could be developed as a combinatorial therapy with MFF for better clinical outcomes.


Asunto(s)
Colitis , Ácido Gálico/análogos & derivados , Microbioma Gastrointestinal , Ratones , Animales , Ácido Micofenólico/farmacología , Ácido Micofenólico/uso terapéutico , Inmunosupresores/uso terapéutico , Glucuronidasa/metabolismo , Bacterias/metabolismo , Colitis/tratamiento farmacológico
16.
Ecotoxicol Environ Saf ; 271: 115993, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38271890

RESUMEN

Bisphenol A (BPA) is one of the environmental endocrine disruptors, due to its chemical stability it exists in abundant concentrations in water and soil consequently accumulating in the food chain and causing many endocrine-related health problems. So far, studies on the effects of BPA on marine invertebrates have focused on acute toxicity, endocrine regulation, reproduction, and development. However, fewer studies have been conducted on marine benthos. The current study aimed to detect the accumulation of BPA and its impact on tissue structure, antioxidant capacity, and immune indexes in marine worm, Urechis unicinctus. U. unicinctus, as a common marine benthic animal, were exposed to different concentrations of BPA. Blood cells and intestinal tract were taken for tissue structure inspection, and supernatant of the coelomic fluid was collected for oxidative and antioxidant biomarkers. Results showed that the accumulation of BPA in muscles of U. unicinctus tended to increase with exposure time. BPA induced a rise in H2O2 and MDA content, and altered the activities of CAT, T-SOD, GST, LSZ and ACP, weaken the immune system functions. Moreover, pathological observation showed that BPA caused severe histopathology in the respiratory intestine, stomach, and midgut. These results will be helpful to understand the response mechanism of U. unicinctus under BPA exposure and provide a reference for controlling the aquaculture conditions and marine water quality of U. unicinctus.


Asunto(s)
Antioxidantes , Fenoles , Poliquetos , Animales , Antioxidantes/farmacología , Peróxido de Hidrógeno/farmacología , Compuestos de Bencidrilo/toxicidad
17.
ACS Appl Mater Interfaces ; 16(5): 6122-6132, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38272468

RESUMEN

One-dimensional conductive fibers that can simultaneously accommodate multiple deformations are crucial materials to enable next-generation electronic textile technologies for applications in the fields of healthcare, energy harvesting, human-machine interactions, etc. Stretchable conductive fibers (SCFs) with high conductivity on their external structure are important for their direct integration with other electronic components. However, the dilemma to achieve high conductivity and concurrently large stretchability is still quite challenging to resolve among conductive fibers with a conductive surface. Here, a three-layer coaxial conductive fiber, which can provide robust electrical performance under various deformations, is reported. A dual conducting structure with a semisolid metallic layer and a stretchable composite layer was designed in the fibers, providing exceptional conductivity and mechanical stability under mechanical strains. The conductive fiber achieved an initial conductivity of 2291.83 S cm-1 on the entire fiber and could be stretched up to 600% strains. With the excellent electromechanical properties of the SCF, we were able to demonstrate different electronic textile applications including physiological monitoring, neuromuscular electrical stimulation, and energy harvesting.

18.
Small ; 20(11): e2306769, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37932007

RESUMEN

Fresh sweat contains a diverse range of physiological indicators that can effectively reflect changes in the body. However, existing wearable sweat detection systems face challenges in efficiently collecting and detecting fresh sweat in real-time. Additionally, they often lack the necessary deformation capabilities, resulting in discomfort for the wearer. Here, a fully elastic wearable electrochemical sweat detection system is developed that integrates a sweat-collecting microfluidic chip, a multi-parameter electrochemical sensor, a micro-heater, and a sweat detection elastic circuit board system. The unique tree-bionic structure of the microfluidic chip significantly enhances the efficiency of fresh sweat collection and discharge, enabling real-time detection by the electrochemical sensors. The sweat multi-parameter electrochemical sensor offers high-precision and high-sensitivity measurements of sodium ions, potassium ions, lactate, and glucose. The electronic system is built on an elastic circuit board that matches perfectly to wrinkled skin, ensuring improved wearing comfort and enabling multi-channel data sampling, processing, and wireless transmission. This state-of-the-art system represents a significant advancement in the field of elastic wearable sweat detection and holds promising potential for extending its capabilities to the detection of other sweat markers or various wearable applications.


Asunto(s)
Técnicas Biosensibles , Dispositivos Electrónicos Vestibles , Sudor/química , Microfluídica , Árboles , Biónica , Iones/análisis , Técnicas Biosensibles/métodos
19.
Angew Chem Int Ed Engl ; 63(1): e202315340, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-37985934

RESUMEN

Despite the fact that d-band center theory links the d electron structure of transition metals to their catalytic activity, it is yet unknown how the synergistic effect of multi-d electrons impacts catalytic performance. Herein, novel LaNi1-x Cox Ru intermetallics containing 5d, 4d, and 3d electrons were prepared. In these compounds, the 5d orbital of La transfers electrons to the 4d orbital of Ru, which provides adsorption sites for H*. The 3d orbitals of Ni and Co interact with the 5d and 4d orbitals to generate an anisotropic electron distribution, which facilitates the adsorption and desorption of OH*. The synergistic effect of multi-d electrons ensures efficient catalytic activity. The optimized LaNi0.5 Co0.5 Ru has an overpotential of 43mV at 10 mA cm-2 for alkaline electrocatalytic hydrogen evolution reaction. Beyond offering a variety of new electrocatalysts, this work reveals the multi-d electron synergy in promoting catalytic reaction.

20.
Nat Chem ; 16(3): 466-475, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38057367

RESUMEN

Although α-chiral C(sp3)-S bonds are of enormous importance in organic synthesis and related areas, the transition-metal-catalysed enantioselective C(sp3)-S bond construction still represents an underdeveloped domain probably due to the difficult heterolytic metal-sulfur bond cleavage and notorious catalyst-poisoning capability of sulfur nucleophiles. Here we demonstrate the use of chiral tridentate anionic ligands in combination with Cu(I) catalysts to enable a biomimetic enantioconvergent radical C(sp3)-S cross-coupling reaction of both racemic secondary and tertiary alkyl halides with highly transformable sulfur nucleophiles. This protocol not only exhibits a broad substrate scope with high enantioselectivity but also provides universal access to a range of useful α-chiral alkyl organosulfur compounds with different sulfur oxidation states, thus providing a complementary approach to known asymmetric C(sp3)-S bond formation methods. Mechanistic results support a biomimetic radical homolytic substitution pathway for the critical C(sp3)-S bond formation step.

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