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1.
Proc Natl Acad Sci U S A ; 121(9): e2316580121, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38377204

RESUMEN

Achieving high-performance materials with superior mechanical properties and electrical conductivity, especially in large-sized bulk forms, has always been the goal. However, it remains a grand challenge due to the inherent trade-off between these properties. Herein, by employing nanodiamonds as precursors, centimeter-sized diamond/graphene composites were synthesized under moderate pressure and temperature conditions (12 GPa and 1,300 to 1,500 °C), and the composites consisted of ultrafine diamond grains and few-layer graphene domains interconnected through covalently bonded interfaces. The composites exhibit a remarkable electrical conductivity of 2.0 × 104 S m-1 at room temperature, a Vickers hardness of up to ~55.8 GPa, and a toughness of 10.8 to 19.8 MPa m1/2. Theoretical calculations indicate that the transformation energy barrier for the graphitization of diamond surface is lower than that for diamond growth directly from conventional sp2 carbon materials, allowing the synthesis of such diamond composites under mild conditions. The above results pave the way for realizing large-sized diamond-based materials with ultrahigh electrical conductivity and superior mechanical properties simultaneously under moderate synthesis conditions, which will facilitate their large-scale applications in a variety of fields.

2.
Environ Res ; 251(Pt 2): 118664, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38499222

RESUMEN

The extensive use of mineral fertilizers has a negative impact on the environment, whereas wastewater and microalgal biomass can provide crops with nutrients such as nitrogen, phosphorus, and potassium, and have the potential to be used as a source of fertilizers in circular agriculture. In this study, a step-by-step resource utilization study of algae-containing wastewater generated from microalgae treatment of swine wastewater was carried out. When wheat seedlings were cultivated in the effluent after microalgae separation, the root fresh weight, seedling fresh weight, and total seedling length were increased by 3.44%, 14.45%, and 13.64%, respectively, compared with that of the algae-containing wastewater, and there was no significant difference in seedling fresh weight, total seedling length, maximum quantum yields of PSII photochemistry (Fv/Fm), and performance index (PIABS) from that of the Hogland solution group, which has the potential to be an alternative liquid fertilizer. Under salt stress, microalgae extract increased the contents of GA3, IAA, ABA, and SA in wheat seedlings, antioxidant enzymes maintained high activity, and the PIABS value increased. Low-dose microalgae extract (1 mL/L) increased the root fresh weight, seedling fresh weight, longest seedling length, and total seedling length by 30.73%, 31.28%, 16.43%, and 28.85%, respectively. Algae extract can act as a plant biostimulant to regulate phytohormone levels to attenuate the damage of salt stress and promote growth.


Asunto(s)
Biomasa , Microalgas , Plantones , Triticum , Aguas Residuales , Triticum/crecimiento & desarrollo , Triticum/efectos de los fármacos , Microalgas/crecimiento & desarrollo , Microalgas/efectos de los fármacos , Plantones/crecimiento & desarrollo , Plantones/efectos de los fármacos , Animales , Aguas Residuales/química , Porcinos , Tolerancia a la Sal , Fertilizantes/análisis , Eliminación de Residuos Líquidos/métodos
3.
BMC Geriatr ; 24(1): 549, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918723

RESUMEN

BACKGROUND: Surgery in geriatric patients often poses risk of major postoperative complications. Acute kidney injury (AKI) is a common complication following noncardiac surgery and is associated with increased mortality. Early identification of geriatric patients at high risk of AKI could facilitate preventive measures and improve patient prognosis. This study used machine learning methods to identify important features and predict AKI following noncardiac surgery in geriatric patients. METHODS: The data for this study were obtained from a prospective cohort. Patients aged ≥ 65 years who received noncardiac surgery from June 2019 to December 2021 were enrolled. Data were split into training set (from June 2019 to March 2021) and internal validation set (from April 2021 to December 2021) by time. The least absolute shrinkage and selection operator (LASSO) regularization algorithm and the random forest recursive feature elimination algorithm (RF-RFE) were used to screen important predictors. Models were trained through extreme gradient boosting (XGBoost), random forest, and LASSO. The SHapley Additive exPlanations (SHAP) package was used to interpret the machine learning model. RESULTS: The training set included 6753 geriatric patients. Of these, 250 (3.70%) patients developed AKI. The XGBoost model with RF-RFE selected features outperformed other models with an area under the precision-recall curve (AUPRC) of 0.505 (95% confidence interval [CI]: 0.369-0.626) and an area under the receiver operating characteristic curve (AUROC) of 0.806 (95%CI: 0.733-0.875). The model incorporated ten predictors, including operation site and hypertension. The internal validation set included 3808 geriatric patients, and 96 (2.52%) patients developed AKI. The model maintained good predictive performance with an AUPRC of 0.431 (95%CI: 0.331-0.524) and an AUROC of 0.845 (95%CI: 0.796-0.888) in the internal validation. CONCLUSIONS: This study developed a simple machine learning model and a web calculator for predicting AKI following noncardiac surgery in geriatric patients. This model may be a valuable tool for guiding preventive measures and improving patient prognosis. TRIAL REGISTRATION: The protocol of this study was approved by the Committee of Ethics from West China Hospital of Sichuan University (2019-473) with a waiver of informed consent and registered at www.chictr.org.cn (ChiCTR1900025160, 15/08/2019).


Asunto(s)
Lesión Renal Aguda , Aprendizaje Automático , Complicaciones Posoperatorias , Humanos , Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/etiología , Lesión Renal Aguda/epidemiología , Anciano , Femenino , Masculino , Estudios Prospectivos , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/etiología , Anciano de 80 o más Años , Medición de Riesgo/métodos , Procedimientos Quirúrgicos Operativos/efectos adversos , Factores de Riesgo
4.
Cell Commun Signal ; 21(1): 347, 2023 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-38049832

RESUMEN

T cell-based adoptive cell therapy (ACT) has exhibited excellent antitumoral efficacy exemplified by the clinical breakthrough of chimeric antigen receptor therapy (CAR-T) in hematologic malignancies. It relies on the pool of functional T cells to retain the developmental potential to serially kill targeted cells. However, failure in the continuous supply and persistence of functional T cells has been recognized as a critical barrier to sustainable responses. Conferring stemness on infused T cells, yielding stem cell-like memory T cells (TSCM) characterized by constant self-renewal and multilineage differentiation similar to pluripotent stem cells, is indeed necessary and promising for enhancing T cell function and sustaining antitumor immunity. Therefore, it is crucial to identify TSCM cell induction regulators and acquire more TSCM cells as resource cells during production and after infusion to improve antitumoral efficacy. Recently, four common cytokine receptor γ chain (γc) family cytokines, encompassing interleukin-2 (IL-2), IL-7, IL-15, and IL-21, have been widely used in the development of long-lived adoptively transferred TSCM in vitro. However, challenges, including their non-specific toxicities and off-target effects, have led to substantial efforts for the development of engineered versions to unleash their full potential in the induction and maintenance of T cell stemness in ACT. In this review, we summarize the roles of the four γc family cytokines in the orchestration of adoptively transferred T cell stemness, introduce their engineered versions that modulate TSCM cell formation and demonstrate the potential of their various combinations. Video Abstract.


Asunto(s)
Linfocitos T CD8-positivos , Citocinas , Inmunoterapia Adoptiva , Células Madre , Transducción de Señal
5.
J Chem Phys ; 158(13): 134711, 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-37031159

RESUMEN

As an important phase-change material, GeTe has many high-pressure phases as well, but its phase transitions under pressure are still lack of clarity. It is challenging to identify high-pressure GeTe crystal structures owing to the phase coexistence in a wide pressure range and the reversibility of phase transitions. Hence, first-principles calculations are required to provide further information in addition to limited experimental characterizations. In this work, a new orthorhombic Cmca GeTe high-pressure phase has been predicted via the CALYPSO method as the most energetically favorable phase in the pressure range between ∼30 and ∼38.5 GPa, which would update the GeTe high-pressure phase transition sequence. The crystal structure of the Cmca phase is composed of alternate stacking puckered layers of Ge six-membered rings and Te four-membered rings along the b direction. The high density of states near the Fermi level and delocalization of electrons from the two-dimensional electron localization function indicate a strong metallic property of the Cmca phase. Electron-phonon coupling calculations indicate that the Cmca phase is superconductive below ∼4.2 K at 35 GPa. The simulated x-ray diffraction pattern of the Cmca phase implies that this phase might coexist with the Pnma-boat phase under high pressure. These results offer further understanding on the high-pressure structural evolution and physical properties in GeTe and other IV-VI semiconductors.

6.
Inorg Chem ; 61(21): 8144-8152, 2022 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-35576525

RESUMEN

In recent years, skutterudite filled with electronegative elements (S, Se, Cl, Br) has attracted the extensive attention of researchers. By doping electron donors (Pb, Ni, or Te, S, Se) at the Co or Sb sites, the electronegative elements can form thermodynamically stable compounds in the intrinsic pores of the skutterudite, substantially expanding the research scope of skutterudite. In this study, S0.05Co4Sb11.3Te0.6Se0.1 skutterudite was synthesized at high pressure and high temperature, with a pressure range of 2.0-3.5 GPa. The phase composition, micro-morphology, and electrical and thermal transport properties were systematically characterized. The micromorphology analysis shows that the introduction of S element and substituting Te and Se at the Sb sites inhibit the grain growth in a suitable high-pressure environment. Substantial differences are observed in the directions of the lattice stripes in the samples, and rich grain boundaries and many lattice distortions and dislocation defects occur. The carrier concentration can be optimized by filling the voids of the skutterudite with a few S atoms, and the thermoelectric properties can be optimized by scattering phonons through resonance scattering and defect scattering. The samples synthesized at a pressure of 3.0 GPa and a temperature of 900 K have a maximum power factor of 23.85 × 10-4 W m-1 K-2 and a maximum zT value of 1.30 at a test temperature of 773 K.

7.
Neuromodulation ; 2022 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-36522251

RESUMEN

OBJECTIVES: Autonomic nervous activity imbalance plays an important role in atrial fibrillation (AF). AF can be treated by acupuncture at the Neiguan point (PC6), but the mechanism remains elusive. Here, we investigated autonomic nervous system activity in electroacupuncture (EA) at PC6 in a rat AF model. MATERIAL AND METHODS: In this study, we established a rat AF model via tail vein injection with ACh-CaCl2 for ten consecutive days with or without EA at PC6. AF inducibility and heart rate variability (HRV) were assessed by electrocardiogram. Next, we completed in vivo recording of the activity of cervical sympathetic and vagal nerves, respectively. Finally, the activities of brain regions related to autonomic nerve regulation were assessed by c-Fos immunofluorescence and multichannel recording. RESULTS: EA at PC6 decreased AF inducibility and prevented changes in HRV caused by ACh-CaCl2 injection. Meanwhile, EA at PC6 reversed the increased sympathetic and decreased vagal nerve activity in AF rats. Furthermore, EA treatment downregulated increased c-Fos expression in brain regions, including paraventricular nucleus, rostral ventrolateral medulla, and dorsal motor nucleus of the vagus in AF, while c-Fos expression in nucleus ambiguus was upregulated with EA. CONCLUSION: The protective effect of EA at PC6 on AF is associated with balance between sympathetic and vagal nerve activities.

8.
Dev Psychobiol ; 63(4): 713-724, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-32974928

RESUMEN

Trial-to-trial intraindividual reaction time variability (IIRTV) serves as an index of attentional control and related endogenous brain function. What determinants contribute to preschoolers' attentional control indexed by IIRTV remains unknown. The present study examined how catechol-o-methyltransferase (COMT) rs4680 polymorphism interacted with family functioning (cohesion and adaptability) to impact on preschoolers' attentional control indexed by IIRTV. One hundred forty-four preschool children (Mage  = 4.19, SD = 0.63) completed the flanker task to assess their IIRTV. Their parents were asked to fill out the Family Adaptability and Cohesion Evaluation Scale II to assess family functioning. After controlling for age, socioeconomic status (SES) and mean reaction time, results showed that the COMT rs4680 polymorphism was positively associated with preschoolers' IIRTV at the 5% significance level (p = .02) but not after multiple testing adjustment (p = .08). Moreover the COMT rs4680 polymorphism significantly interacted with family functioning to impact on preschoolers' IIRTV and the interaction effects remained significant after correction for multiple testing (p = .01, ΔR2  = 0.06 in congruent conditions; p = .04, ΔR2  = 0.04 in combined conditions). In addition, the significant interaction between SES and COMT rs4680 polymorphism was also found in the present study (p = .01, ΔR2  = 0.05 in congruent conditions; p = .05, ΔR2  = 0.03 in combined conditions). No sex differences were found in the present sample. The findings of the present study expand our knowledge about the gene × environment underpinnings of children's attentional control and endogenous brain function, and provide evidence for the Vantage Sensitivity model on children's development.


Asunto(s)
Atención , Catecol O-Metiltransferasa , Catecol O-Metiltransferasa/genética , Preescolar , Genotipo , Humanos , Padres , Polimorfismo de Nucleótido Simple , Tiempo de Reacción
10.
Arch Microbiol ; 202(5): 1005-1013, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31932863

RESUMEN

Pectinase is widely used in numerous industrial fields, including the food, wine, and paper industries. In this work, seven bacteria were isolated from orange peel and their pectinase production activity was assayed. One bacterium (OR-B2) identified as a Bacillus sp. showed the highest enzyme activity towards others. A gene encoding a pectate lyase designed as PelB-B2 in this work was amplified and heterogeneous expressed in E.coli. PelB-B2 was defined as a member of the PelB pectate lyase family after phylogenic tree analysis. 3D model of PelB-B2 was constructed by SWISS-MODEL and PelB-B2 showed conserved para-ß structure. After inducing culture and purified by Ni-affinity chromatography, the properties of the purified PelB-B2 were assayed. Optimal pH and temperature for PelB-B2 was pH 8.0 and 50 °C, respectively. PelB-B2 showed excellent pH stability and thermostability. It was stable within pH range 3.0-11.0 and retained more than 51% activity after incubation at 40 °C, 50 °C, or 60 °C for 1 h. Furthermore, we determined that PelB-B2 was a Ca2+-dependent pectinase and the pectin extracted from citrus was the benefit substrate for PelB-B2. The Km and Vmax of PelB-B2 were 1.64 g/L and 232.56 mol/(L min), respectively. The OR-B2 can be a new resource for pectinase production and the PelB-B2 has potential for industrial application. 7 bacteria were isolated from orange peel, namely OR-B1 to OR-B7 and their pectinase activities were assayed. One pectate lyase belongs to PelB family was cloned from OR-B2 and heterogeneous expressed in E. coli. Purified PelB-B2 was further studied with its properties. Effects of pH, temperature, chemicals, substrate on the enzyme activity were assayed and the enzyme kinetic was also measured.


Asunto(s)
Bacillus/enzimología , Pectinas/metabolismo , Poligalacturonasa/metabolismo , Bacillus/genética , Bacillus/metabolismo , Citrus/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Concentración de Iones de Hidrógeno , Cinética , Poligalacturonasa/biosíntesis , Polisacárido Liasas/metabolismo , Temperatura
11.
Molecules ; 26(1)2020 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-33379377

RESUMEN

This study developed a nano-magnetite-modified biochar material (m-biochar) using a simple and rapid in situ synthesis method via microwave treatment, and systematically investigated the removal capability and mechanism of chromium (VI) by this m-biochar from contaminated groundwater. The m-biochar was fabricated from reed residues and magnetically modified by nano-Fe3O4. The results from scanning electron microscopy (SEM) and X-ray diffraction (XRD) characterisations confirmed the successful doping of nano-Fe3O4 on the biochar with an improved porous structure. The synthesised m-biochar exhibited significantly higher maximum adsorption capacity of 9.92 mg/g compared with that (8.03 mg/g) of the pristine biochar. The adsorption kinetics followed the pseudo-second-order model and the intraparticle diffusion model, which indicated that the overall adsorption rate of Cr(VI) was governed by the processes of chemical adsorption, liquid film diffusion and intramolecular diffusion. The increasing of the pH from 3 to 11 significantly affected the Cr(VI) adsorption, where the capabilities decreased from 9.92 mg/g to 0.435 mg/g and 8.03 mg/g to 0.095 mg/g for the m-biochar and pristine biochar, respectively. Moreover, the adsorption mechanisms of Cr(VI) by m-biochar were evaluated and confirmed to include the pathways of electrostatic adsorption, reduction and complexation. This study highlighted an effective synthesis method to prepare a superior Cr(VI) adsorbent, which could contribute to the effective remediation of heavy metal contaminations in the groundwater.


Asunto(s)
Carbón Orgánico/química , Cromo/química , Óxido Ferrosoférrico/química , Agua Subterránea/química , Contaminantes Químicos del Agua/química , Adsorción , Concentración de Iones de Hidrógeno , Cinética , Magnetismo/métodos , Microondas , Nanopartículas
12.
Anal Chem ; 90(6): 3849-3855, 2018 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-29451779

RESUMEN

Optical detection has become a convenient and scalable approach to read out information from microfluidic systems. For the study of many key biomolecules, however, including peptides and proteins, which have low fluorescence emission efficiencies at visible wavelengths, this approach typically requires labeling of the species of interest with extrinsic fluorophores to enhance the optical signal obtained - a process which can be time-consuming, requires purification steps, and has the propensity to perturb the behavior of the systems under study due to interactions between the labels and the analyte molecules. As such, the exploitation of the intrinsic fluorescence of protein molecules in the UV range of the electromagnetic spectrum is an attractive path to allow the study of unlabeled proteins. However, direct visualization using 280 nm excitation in microfluidic devices has to date commonly required the use of coherent sources with frequency multipliers and devices fabricated out of materials that are incompatible with soft lithography techniques. Here, we have developed a simple, robust, and cost-effective 280 nm LED platform that allows real-time visualization of intrinsic fluorescence from both unlabeled proteins and protein complexes in polydimethylsiloxane microfluidic channels fabricated through soft lithography. Using this platform, we demonstrate intrinsic fluorescence visualization of proteins at nanomolar concentrations on chip and combine visualization with micron-scale diffusional sizing to measure the hydrodynamic radii of individual proteins and protein complexes under their native conditions in solution in a label-free manner.


Asunto(s)
Técnicas Analíticas Microfluídicas/instrumentación , Proteínas/análisis , Animales , Bovinos , Pollos , Difusión , Dimetilpolisiloxanos/química , Diseño de Equipo , Fluorescencia , Hidrodinámica , Dispositivos Laboratorio en un Chip , Muramidasa/análisis , Albúmina Sérica Bovina/análisis , Soluciones , Cadena B de alfa-Cristalina/análisis
13.
Inorg Chem ; 56(18): 11275-11281, 2017 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-28853562

RESUMEN

We developed suitable high-pressure and high-temperature (HPHT) conditions for improvement of the thermoelectric properties of nonstoichiometric TiO1.80. X-ray diffraction, scanning transmission microscopy, transmission electron microscopy, and ultraviolet spectral measurements demonstrate that the crystal structures and microstructures are strongly modulated by our HPHT. The electrical properties and thermal conductivity are improved simultaneously by raising the reactive sintering pressure. The band gap was narrowed, contributing to the increase of the electrical properties with the pressure. In addition, relatively low thermal conductivities were obtained here as a result of a full spectrum of phonon scattering, benefiting from our deliberately engineered microstructures via HPHT. As a consequence, a high dimensionless figure of merit (zT) of 0.36 was obtained at 700 °C in the sample fabricated at 5 GPa. As far as we know, this is higher than all of the results of nonstoichiometric titanium oxide by other means and an enhancement of 57% of the best ever result. HPHT offers us a promising alternative for optimization of the thermoelectric properties, and it is worthwhile to popularize it.

14.
Artículo en Inglés | MEDLINE | ID: mdl-38954799

RESUMEN

Alzheimer's disease (AD) has a complex etiology and diverse pathological processes. The therapeutic effect of single-target drugs is limited, so simultaneous intervention of multiple targets is gradually becoming a new research trend. Critical stages in AD progression involve amyloid-ß (Aß) self-aggregation, metal-ion-triggered fibril formation, and elevated reactive oxygen species (ROS). Herein, red blood cell membranes (RBC) are used as templates for the in situ growth of cerium oxide (CeO2) nanocrystals. Then, carbon quantum dots (CQDs) are encapsulated to form nanocomposites (CQD-Ce-RBC). This strategy is combined with photothermal therapy (PTT) for AD therapy. The application of RBC enhances the materials' biocompatibility and improves immune evasion. RBC-grown CeO2, the first application in the field of AD, demonstrates outstanding antioxidant properties. CQD acts as a chelating agent for copper ions, which prevents the aggregation of Aß. In addition, the thermal effect induced by near-infrared laser-induced CQD can break down Aß fibers and improve the permeability of the blood-brain barrier. In vivo experiments on APP/PS1 mice demonstrate that CQD-Ce-RBC combined with PTT effectively clears cerebral amyloid deposits and significantly enhances learning and cognitive abilities, thereby retarding disease progression. This innovative multipathway approach under light-induced conditions holds promise for AD treatment.

15.
J Colloid Interface Sci ; 663: 856-868, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38447400

RESUMEN

Mitochondrial dysfunction and metal ion imbalance are recognized as pathological hallmarks of Alzheimer's Disease (AD), leading to deposition of ß-amyloid (Aß) thereby and inducing neurotoxicity, activating apoptosis, eliciting oxidative stress, and ultimately leading to cognitive impairment. In this study, the red blood cell membrane (RBC) was used as a vehicle for encapsulating carbon quantum dots (CQD) and polydopamine (PDA), creating a nanocomposite (PDA-CQD/RBC). This nanocomposite was combined with near-infrared light (NIR) for AD treatment. The RBC offers anti-immunorecognition properties to evade immune clearance, PDA exhibits enzyme-mimicking activity to mitigate oxidative stress damage, and CQD acts as a chelating agent for metal ions (Cu2+), effectively preventing Cu2+-mediated aggregation of Aß. Furthermore, the local heating induced by near-infrared laser irradiation can dismantle the formed Aß fibers and enhance the blood-brain barrier's permeability. Both in vitro and animal experiments have shown that PDA-CQD/RBC, in combination with NIR, mitigates neuroinflammation, and ameliorates behavioral deficits in mice. This approach targets multiple pathological pathways, surpassing the limitations of single-target treatments and enhancing therapeutic efficacy while decelerating disease progression.


Asunto(s)
Enfermedad de Alzheimer , Indoles , Polímeros , Puntos Cuánticos , Ratones , Animales , Enfermedad de Alzheimer/tratamiento farmacológico , Membrana Eritrocítica/metabolismo , Membrana Eritrocítica/patología , Péptidos beta-Amiloides , Metales , Rayos Infrarrojos , Carbono/farmacología
16.
Colloids Surf B Biointerfaces ; 238: 113887, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38581835

RESUMEN

Alzheimer's disease (AD) is complex and multifactorial, and its pathogenesis involves multiple factors and processes. This study pioneered the in situ growth of cerium oxide nanoparticles on macrophage membranes (Ce-RAW). Further, carbon quantum dots (CQD) were biomimetically modified by Ce-RAW, leading to the synthesis of a multifunctional nanocomposite (CQD-Ce-RAW). Within the framework of this research, CQD-Ce-RAW was strategically combined with photothermal therapy (PTT), aiming to achieve a more significant therapeutic effect. The macrophage membrane confers the system with anti-phagocytic and anti-inflammatory biological functions. More importantly, the ultra-small size of cerium oxide grown on the membrane acts as a reactive oxygen species (ROS) scavenger and alleviates the degree of oxidative stress. Meanwhile, CQD as a photosensitizer helps dissociate amyloid-ß (Aß) aggregates and chelates excess copper ions, thus further inhibiting Aß aggregation. Cell experiments showed that CQD-Ce-RAW combined with PTT could effectively degrade and inhibit the aggregation of Aß, remove ROS, and improve cell survival rate. The results of in vivo photothermal experiments demonstrated that near-infrared light enhanced the efficiency of drug penetration through the blood-brain barrier and facilitated its accumulation in brain tissue. This comprehensive therapeutic approach can intervene in the disease progression from multiple pathways, providing a new prospect for treating AD.


Asunto(s)
Enfermedad de Alzheimer , Biopelículas , Cerio , Nanopartículas , Terapia Fototérmica , Especies Reactivas de Oxígeno , Cerio/química , Cerio/farmacología , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/terapia , Enfermedad de Alzheimer/patología , Animales , Ratones , Nanopartículas/química , Biopelículas/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Puntos Cuánticos/química , Péptidos beta-Amiloides/metabolismo , Supervivencia Celular/efectos de los fármacos , Tamaño de la Partícula , Células RAW 264.7 , Humanos , Propiedades de Superficie , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos
17.
Spectrochim Acta A Mol Biomol Spectrosc ; 321: 124693, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38909555

RESUMEN

In this paper, a method for indirect diagnosis of transformer faults based on the fluorescence spectrum and characteristic wavelength screening of transformer oil has been proposed. Specifically, a hybrid strategy (BiPLS-RF) for establishing the fluorescence spectrum feature screening of transformer oil using backward interval partial least squares (BiPLS) and random forest (RF) has been proposed. Aiming at the problem of transformer fault diagnosis, the laser induced fluorescence (LIF) spectroscopy of transformer oil in different states was first collected, and it is found that the fluorescence spectrum intensity of normal transformer oil was stronger than that of faulty transformer oil. Then the characteristic bands of the original fluorescence spectra were screened by BiPLS. It is found that when the original fluorescence spectra were divided into 15 sub-intervals, the minimum root mean squares error of cross-validation can be obtained by selecting 3 sub-intervals (including 411 wavelengths). On this basis, RF was employed to further screen the characteristic wavelengths and realized the identification of the fluorescence spectrum. It is found that in the RF model composed of 54 trees, the selected 196 characteristic wavelengths of the fluorescence spectrum can minimize the analysis error (0.56%). In addition, the selected characteristic wavelength information was fed into other common classifiers to construct a fluorescence spectrum identification model, which further proved the effectiveness of BiPLS-RF for wavelength selection for LIF spectroscopy of power transformer oil. The results show that it is feasible to use BiPLS-RF to screen the characteristic wavelength of LIF spectroscopy and apply it to transformer fault diagnosis, which provides a new solution for transformer fault diagnosis.

18.
Int J Radiat Biol ; 100(2): 248-255, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37747796

RESUMEN

BACKGROUND: The relationship among body mass index (BMI), setup error and radiation pneumonitis is not clearly illustrated. OBJECTIVE: The present study aimed to investigate the role of BMI in non-small cell lung cancer (NSCLC) patients' radiation treatment, focusing on its relationship with setup error of patient positioning, the dosimetric parameters of intensity-modulated radiation therapy (IMRT) and the incidence of radiation pneumonitis. METHODS: This prospective observational study included 523 cases of NSCLC patients during 2020-2022. Patients were divided into different groups by different BMI. The setup error was obtained by cone beam CT (CBCT) at three positions, lateral (LAT), longitudinal (LNG) and vertical (VRT). IMRT dosimetric parameters of V5, V20, and mean dose were collected. RESULTS: Patients with BMI ≥28 kg/m2 showed significantly higher absolute values of LAT, LNG and VRT, higher V5, V20, mean dose, as well as higher total incidence of radiation pneumonitis and grade III radiation pneumonitis compared with patients with BMI <24 kg/m2 or 24-28 kg/m2. Spearman's analysis demonstrated that the absolute values of LAT, LNG and VRT were positively correlated with BMI, and positive correlation existed among BMI, dosimetric parameters and setup errors. ROC curves showed that LAT in setup errors and V5 in dosimetric parameters had the best diagnostic value for prediction of radiation pneumonitis. Only BMI, LAT, V5 and V20 were the independent risk factors for radiation pneumonitis. CONCLUSIONS: Setup error caused by higher BMI might be associated with the dosimetric parameters, as well as the incidence of radiation pneumonitis in NSCLC patients.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Neumonitis por Radiación , Radioterapia de Intensidad Modulada , Humanos , Carcinoma de Pulmón de Células no Pequeñas/complicaciones , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neumonitis por Radiación/epidemiología , Neumonitis por Radiación/etiología , Radioterapia de Intensidad Modulada/efectos adversos , Índice de Masa Corporal , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/radioterapia , Incidencia , Dosificación Radioterapéutica , Estudios Retrospectivos
19.
Microbiol Spectr ; 11(1): e0366722, 2023 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-36651776

RESUMEN

With the spread of multidrug-resistant bacteria, there has been an increasing focus on molecular classes that have not yet yielded an antibiotic. A key capability for assessing and prescribing new antibacterial treatments is to compare the effects antibacterial agents have on bacterial growth at a phenotypic, single-cell level. Here, we combined time-lapse microscopy with microfluidics to investigate the concentration-dependent killing kinetics of stationary-phase Escherichia coli cells. We used antibacterial agents from three different molecular classes, ß-lactams and fluoroquinolones, with the known antibiotics ampicillin and ciprofloxacin, respectively, and a new experimental class, protein Ψ-capsids. We found that bacterial cells elongated when treated with ampicillin and ciprofloxacin used at their minimum inhibitory concentration (MIC). This was in contrast to Ψ-capsids, which arrested bacterial elongation within the first two hours of treatment. At concentrations exceeding the MIC, all the antibacterial agents tested arrested bacterial growth within the first 2 h of treatment. Further, our single-cell experiments revealed differences in the modes of action of three different agents. At the MIC, ampicillin and ciprofloxacin caused the lysis of bacterial cells, whereas at higher concentrations, the mode of action shifted toward membrane disruption. The Ψ-capsids killed cells by disrupting their membranes at all concentrations tested. Finally, at increasing concentrations, ampicillin and Ψ-capsids reduced the fraction of the population that survived treatment in a viable but nonculturable state, whereas ciprofloxacin increased this fraction. This study introduces an effective capability to differentiate the killing kinetics of antibacterial agents from different molecular classes and offers a high content analysis of antibacterial mechanisms at the single-cell level. IMPORTANCE Antibiotics act against bacterial pathogens by inhibiting their growth or killing them directly. Different modes of action determine different antibacterial responses, whereas phenotypic differences in bacteria can challenge the efficacy of antibiotics. Therefore, it is important to be able to differentiate the concentration-dependent killing kinetics of antibacterial agents at a single-cell level, in particular for molecular classes which have not yielded an antibiotic before. Here, we measured single-cell responses using microfluidics-enabled imaging, revealing that a novel class of antibacterial agents, protein Ψ-capsids, arrests bacterial elongation at the onset of treatment, whereas elongation continues for cells treated with ß-lactam and fluoroquinolone antibiotics. The study advances our current understanding of antibacterial function and offers an effective strategy for the comparative design of new antibacterial therapies, as well as clinical antibiotic susceptibility testing.


Asunto(s)
Ampicilina , Antibacterianos , Antibacterianos/farmacología , Ampicilina/farmacología , Ciprofloxacina/farmacología , Fluoroquinolonas/farmacología , Bacterias , beta-Lactamas/farmacología , Escherichia coli , Pruebas de Sensibilidad Microbiana
20.
Int J Hypertens ; 2023: 1432727, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36959846

RESUMEN

Objectives: Previous studies reported that there were disparities in hypertension management among different ethnic groups, and this study aimed to systematically determine the prevalence, awareness, treatment, and control rates of hypertension in multiple Chinese ethnic groups. Methods: We searched Embase, PubMed, and Web of Science for articles up to 25 October, 2022. The pooled prevalence, awareness, treatment, and control rates of hypertension were estimated with 95% confidence intervals (CI). The heterogeneity of estimates among studies was assessed by the Cochran Q test and I 2 statistic. Meta-regression analyses were conducted to identify the factors influencing the heterogeneity of the pooled prevalence, awareness, treatment, and control rate of hypertension. Results: In total, 45 publications including 193,788 cases and 587,826 subjects were eligible for the analyses. The lowest prevalence was found in the Han group (27.0%), and the highest prevalence was in the Mongolian population (39.8%). The awareness rates ranged from 24.4% to 58.0% in the four ethnic groups. Both the highest treatment and control rates were found in the Mongolian population (50.6% and 16.0%, respectively), whereas the Yi group had the lowest control rate (8.0%). In addition, the study year, the mean age of subjects, mean body mass index of subjects, tobacco use (%), alcohol use (%), residence (urban%), and education (primary school%) had varied effects on heterogeneity. Conclusions: These findings highlight the disparities in prevalence, awareness, treatment, and control rates of hypertension in a different ethnic population of China, which could provide suggestions for making targeted prevention measures.

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