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1.
J Nutr ; 154(4): 1262-1270, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38367806

RESUMEN

BACKGROUND: The relationship between whole grain intake and chronic kidney disease (CKD) remains uncertain. OBJECTIVE: This study aimed to evaluate the association between whole grain intake and risk of CKD in Chinese adults. METHODS: The present cross-sectional study used data from the China Health and Nutrition Survey conducted in 2009. Whole grain intake was measured using 3 consecutive 24-h dietary recalls and a household food inventory. A multivariable logistic regression model was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for risk of CKD. In addition, a restricted cubic spline was used to investigate the dose‒response relationship between whole grain and risk of CKD. RESULTS: A total of 6747 participants were included, 728 of whom had CKD. Compared with those in the lowest whole grain intake group, those in the higher grain intake group had an inverse association with risk of CKD (Q2: adjusted OR 0.70, 95% CI: 0.54, 0.89; Q3: adjusted OR 0.54, 95% CI: 0.42, 0.69; and Q4: adjusted OR 0.29, 95% CI: 0.21, 0.41). The association between whole grain intake and CKD seems to be stronger for individuals who were male (P for interaction = 0.008) or smokers (P for interaction = 0.013). In addition, the restricted cubic spline suggested an obvious L-shaped correlation. CONCLUSIONS: Increased whole grain intake was associated with a decreased risk of CKD in Chinese adults.


Asunto(s)
Insuficiencia Renal Crónica , Granos Enteros , Adulto , Humanos , Masculino , Femenino , Estudios Transversales , Insuficiencia Renal Crónica/epidemiología , Dieta , Encuestas Nutricionales
2.
World J Urol ; 42(1): 21, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38198015

RESUMEN

OBJECTIVE: This research aims to explore the efficiency and safety of endoscopic combined intrarenal surgery (Micro-ECIRS) composed of micro-percutaneous nephrolithotomy (Micro-perc) and retrograde intrarenal surgery (RIRS) in the Galdakao-modified supine Valdivia (GMSV) position for a single session for the treatment of complex nephrolithiasis in children. MATERIALS AND METHODS: This study retrospectively reviewed patients aged < 18 years who underwent Micro-ECIRS in the GMSV position for renal stones larger than 2 cm under ultrasound guidance between August 2020 to May 2022 at our institution. RESULTS: A total of 13 patients (8 males and 5 females) received Micro-ECIRS for renal stones under ultrasound guidancewhile adopting the GMSV position. The average stone size was 2.7 cm (range: 2.1-3.7 cm). Among them, 6 patients had left kidney stones, 5 patients had right kidney stones, and 2 patients had bilateral kidney stones. The mean operative time was 70.5 min (range: 54-93 min). The mean hospital stay was 6.4 days (range: 4-9 days). The mean hemoglobin decrease was 8.2 g/L (range: 5.1-12.4 g/L). The total number of kidneys that had complete stone clearance was 8 kidneys at 48 h postoperatively, 11 kidneys at 2 weeks postoperatively, and 14 kidneys at 1 month postoperatively. CONCLUSION: Our results demonstrate that Micro-ECIRS while patients are in the GMSV position is a safe and effective method for the treatment of complex children nephrolithiasis. However, all children made three hospital visits and received anesthesia three times. Further research is needed to confirm these findings.


Asunto(s)
Anestesiología , Cálculos Renales , Nefrolitotomía Percutánea , Niño , Femenino , Masculino , Humanos , Estudios Retrospectivos , Cálculos Renales/diagnóstico por imagen , Cálculos Renales/cirugía , Riñón/diagnóstico por imagen , Riñón/cirugía
3.
Eur J Nutr ; 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38814365

RESUMEN

IMPORTANCE: Epidemiological evidences regarding the association between whole grain intake and the risk of new-onset hypertension are still controversial. OBJECTIVE: We aimed to investigate the relationship between whole grain intake and new-onset hypertension and examine possible effect modifiers in the general population. METHODS: A total of 10,973 participants without hypertension from the China Health and Nutrition Survey were enrolled, with follow-up beginning in 1997 and ending in 2015. Whole grain intake was assessed by 3 consecutive 24-h dietary recalls combined with a household food inventory. Multivariable hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards regression model after adjusting for potential risk factors. RESULTS: During a median follow-up of 7.0 years, 3,733 participants developed new-onset hypertension. The adjusted HRs (95% CIs) were as follows: for quartile 2 (HR: 0.52; 95% CI: 0.47-0.57), quartile 3 (HR: 0.46; 95% CI: 0.42-0.51), and quartile 4 (HR: 0.35; 95% CI: 0.31-0.38), compared with quartile 1. Different types of whole grain types, including wheat (adjusted HR, 0.35; 95% CI, 0.32-0.39), maize (adjusted HR, 0.50; 95% CI, 0.42-0.59), and millet (adjusted HR, 0.38; 95% CI, 0.30-0.48), showed significant associations with a reduced risk of hypertension. The association between whole grain intake and new-onset hypertension was stronger in individuals with older age (P for interaction < 0.001) and higher BMI (P for interaction < 0.001). CONCLUSION: Higher consumption of whole grains was significantly associated with a lower risk of new-onset hypertension. This study provides further evidence supporting the importance of increasing whole grain intake for hypertension prevention among Chinese adults.

4.
Cereb Cortex ; 33(23): 11287-11299, 2023 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-37804238

RESUMEN

In recent years, speech perception research has benefited from low-frequency rhythm entrainment tracking of the speech envelope. However, speech perception is still controversial regarding the role of speech envelope and temporal fine structure, especially in Mandarin. This study aimed to discuss the dependence of Mandarin syllables and tones perception on the speech envelope and the temporal fine structure. We recorded the electroencephalogram (EEG) of the subjects under three acoustic conditions using the sound chimerism analysis, including (i) the original speech, (ii) the speech envelope and the sinusoidal modulation, and (iii) the fine structure of time and the modulation of the non-speech (white noise) sound envelope. We found that syllable perception mainly depended on the speech envelope, while tone perception depended on the temporal fine structure. The delta bands were prominent, and the parietal and prefrontal lobes were the main activated brain areas, regardless of whether syllable or tone perception was involved. Finally, we decoded the spatiotemporal features of Mandarin perception from the microstate sequence. The spatiotemporal feature sequence of the EEG caused by speech material was found to be specific, suggesting a new perspective for the subsequent auditory brain-computer interface. These results provided a new scheme for the coding strategy of new hearing aids for native Mandarin speakers.


Asunto(s)
Percepción del Habla , Humanos , Ruido , Percepción del Timbre , Acústica del Lenguaje , Electroencefalografía , Estimulación Acústica
5.
Molecules ; 29(13)2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38999112

RESUMEN

With the rapid development of industry, the discharge of heavy metal-containing wastewater poses a significant threat to aquatic and terrestrial environments as well as human health. This paper provides a brief introduction to the basic principles of ion-imprinted polymer preparation and focuses on the interaction between template ions and functional monomers. We summarized the current research status on typical heavy metal ions, such as Cu(II), Ni(II), Cd(II), Hg(II), Pb(II), and Cr(VI), as well as metalloid metal ions of the As and Sb classes. Furthermore, it discusses recent advances in multi-ion-imprinted polymers. Finally, the paper addresses the challenges faced by ion-imprinted technology and explores its prospects for application.

6.
J Am Chem Soc ; 145(26): 14260-14266, 2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37347164

RESUMEN

Photoelectrodes consisting of metal-insulator-semiconductor (MIS) junctions are a promising candidate architecture for water splitting and for the CO2 reduction reaction (CO2RR). The photovoltage is an essential indicator of the driving force that a photoelectrode can provide for surface catalytic reactions. However, for MIS photoelectrodes that contain metal nanoparticles, direct photovoltage measurements at the metal sites under operational conditions remain challenging. Herein, we report a new in situ spectroscopic approach to probe the quasi-Fermi level of metal catalyst sites in heterogeneous MIS photoelectrodes via surface-enhanced Raman spectroscopy. Using a CO2RR photocathode, nanoporous p-type Si modified with Ag nanoparticles, as a prototype, we demonstrate a selective probe of the photovoltage of ∼0.59 V generated at the Si/SiOx/Ag junctions. Because it can directly probe the photovoltage of MIS heterogeneous junctions, this vibrational Stark probing approach paves the way for the thermodynamic evaluation of MIS photoelectrodes with varied architectural designs.

7.
J Am Chem Soc ; 145(5): 2860-2869, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36715560

RESUMEN

Photoelectrochemical solar fuel generation at the semiconductor/liquid interface consists of multiple elementary steps, including charge separation, recombination, and catalytic reactions. While the overall incident light-to-current conversion efficiency (IPCE) can be readily measured, identifying the microscopic efficiency loss processes remains difficult. Here, we report simultaneous in situ transient photocurrent and transient reflectance spectroscopy (TRS) measurements of titanium dioxide-protected gallium phosphide photocathodes for water reduction in photoelectrochemical cells. Transient reflectance spectroscopy enables the direct probe of the separated charge carriers responsible for water reduction to follow their kinetics. Comparison with transient photocurrent measurement allows the direct probe of the initial charge separation quantum efficiency (ϕCS) and provides support for a transient photocurrent model that divides IPCE into the product of quantum efficiencies of light absorption (ϕabs), charge separation (ϕCS), and photoreduction (ϕred), i.e., IPCE = ϕabsϕCSϕred. Our study shows that there are two general key loss pathways: recombination within the bulk GaP that reduces ϕCS and interfacial recombination at the junction that decreases ϕred. Although both loss pathways can be reduced at a more negative applied bias, for GaP/TiO2, the initial charge separation loss is the key efficiency limiting factor. Our combined transient reflectance and photocurrent study provides a time-resolved view of microscopic steps involved in the overall light-to-current conversion process and provides detailed insights into the main loss pathways of the photoelectrochemical system.

8.
J Am Chem Soc ; 145(1): 676-688, 2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36538810

RESUMEN

Exploiting noble-metal-free systems for high-performance photocatalytic CO2 reduction still presents a key challenge, partially due to the long-standing difficulties in developing potent and durable earth-abundant photosensitizers. Therefore, based on the very cheap aluminum metal, we have deployed a systematic series of homoleptic Al(III) photosensitizers featuring 2-pyridylpyrrolide ligands for CO2 photoreduction. The combined studies of steady-state and time-resolved spectroscopy as well as quantum chemical calculations demonstrate that in anerobic CH3CN solutions at room temperature, visible-light excitation of the Al(III) photosensitizers leads to an efficient population of singlet excited states with nanosecond-scale lifetimes and notable emission quantum yields (10-40%). The results of transient absorption spectroscopy further identified the presence of emissive singlet and unexpectedly nonemissive triplet excited states. More importantly, the introduction of methyl groups at the pyrrolide rings can greatly improve the visible-light absorption, reducing power, and durability of the Al(III) photosensitizers. With triethanolamine, BIH (1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole), and an Fe(II)-quaterpyridine catalyst, the most methylated Al(III) photosensitizer achieves an apparent quantum efficiency of 2.8% at 450 nm for selective (>99%) CO2-to-CO conversion, which is nearly 28 times that of the unmethylated one (0.1%) under identical conditions. The optimal system realizes a maximum turnover number of 10250 and higher robustness than the systems with Ru(II) and Cu(I) benchmark photosensitizers. Quenching experiments using fluorescence spectroscopy elucidate that the photoinduced electron transfer in the Al(III)-sensitized system follows a reductive quenching pathway. The remarkable tunability and cost efficiency of these Al(III) photosensitizers should allow them as promising components in noble-metal-free systems for solar fuel conversion.

9.
World J Urol ; 41(3): 837-841, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36749393

RESUMEN

OBJECTIVE: We aimed to explore the applicability and safety of micro-percutaneous nephrolithotomy (micro-perc) in the treatment of children with kidney stones in the Galdakao-modified supine Valdivia (GMSV) position under the guidance of whole-course ultrasound. MATERIALS AND METHODS: Patients were aged < 18 years in the GMSV position who underwent micro-perc for kidney stones under ultrasound guidance between August 2020 and May 2022 at our institution were reviewed retrospectively. RESULTS: A total of 23 patients, 15 males and 8 females, received micro-perc. The average stone size was 1.6 cm (range 1.1-2.0 cm). Among them, 12 patients had left kidney stones, 10 patients had right kidney stones, and 1 patient had bilateral kidney stones. The mean operative time was 55.3 min (range 35-86 min). The mean hospital stay was 2.9 days (range 2-4 days). The mean hemoglobin decrease was 1.7 g/L (range 0.9-3.2 g/L). A total of 17 patients had complete stone clearance at 48 h postoperatively. A total of 22 patients had complete stone clearance at 2 weeks postoperatively. CONCLUSION: Our results demonstrate that micro-perc under ultrasound guidance is a safe and effective method for the treatment of children with kidney stones in the GMSV position. Further research is warranted to confirm these results.


Asunto(s)
Cálculos Renales , Nefrolitotomía Percutánea , Nefrostomía Percutánea , Masculino , Femenino , Humanos , Niño , Estudios Retrospectivos , Nefrostomía Percutánea/métodos , Cálculos Renales/diagnóstico por imagen , Cálculos Renales/cirugía , Riñón/cirugía , Nefrolitotomía Percutánea/métodos , Posición Supina , Resultado del Tratamiento
10.
Methods ; 204: 410-417, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35447360

RESUMEN

The human auditory system extracts valid information in noisy environments while ignoring other distractions, relying primarily on auditory attention. Studies have shown that the cerebral cortex responds differently to the sound source locations and that auditory attention is time-varying. In this work, we proposed a data-driven encoder-decoder architecture model for auditory attention detection (AAD), denoted as AAD-transformer. The model contains temporal self-attention and channel attention modules and could reconstruct the speech envelope by dynamically assigning weights according to the temporal self-attention and channel attention mechanisms of electroencephalogram (EEG). In addition, the model is conducted based on data-driven without additional preprocessing steps. The proposed model was validated using a binaural listening dataset, in which the speech stimulus was Mandarin, and compared with other models. The results showed that the decoding accuracy of the AAD-transformer in the 0.15-second decoding time window was 76.35%, which was much higher than the accuracy of the linear model using temporal response function in the 3-second decoding time window (increased by 16.27%). This work provides a novel auditory attention detection method, and the data-driven characteristic makes it convenient for neural-steered hearing devices, especially those who speak tonal languages.


Asunto(s)
Percepción del Habla , Percepción Auditiva/fisiología , Corteza Cerebral , Electroencefalografía/métodos , Humanos , Habla , Percepción del Habla/fisiología
11.
Epilepsy Behav ; 145: 109354, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37473654

RESUMEN

BACKGROUND: Studies have shown conflicting results in the correlation between serotonin-1A (5-HT1A) receptor binding levels in the brain and temporal lobe epilepsy (TLE). There is a need to systematically evaluate the correlation between the 5-HT1A binding level and TLE from the perspective of the brain using molecular imaging. METHODS: Chinese and English databases, such as the China National Knowledge Infrastructure (CNKI), the China Science and Technology Journal Database (VIP), WanFang, the Chinese Biomedical Literature Service System (SinoMed), PubMed and Web of Science, were searched. RESULTS: Two evaluators independently screened the literature, extracted data, and evaluated the risk of bias in the included studies according to the inclusion and exclusion criteria. RevMan 5.4.1 was used to analyze the data. A total of 196 participants were included; of these, 95 had TLE and 131 were healthy controls who had never had a seizure before participating in the study. Meta-analysis results suggested that 1) decreased 5-HT1A binding was found on the affected side of patients with TLE (standard mean difference (SMD) = -1.45, 95% confidence interval (CI) [-2.27, -0.64], Z = 3.48, P = 0.0005); 2) decreased 5-HT1A binding was found in the ipsilateral hippocampus of patients with TLE (SMD = -1.76, 95% CI [-2.51, -1.00], Z = 4.57, P<0.00001); 3) decreased 5-HT1A binding was found in the ipsilateral temporal lobe cortex of patients with TLE (SMD = -0.46, 95% CI [-0.80, -0.12], Z = 2.66, P = 0.008); 4) decreased 5-HT1A binding was found in the ipsilateral amygdala in patients with TLE (SMD = -1.36, 95% CI [-2.48, -0.23], Z = 2.37, P = 0.02); and 5) decreased 5-HT1A binding was found in the frontal lobe of patients with TLE(SMD = -0.75, 95% CI [-1.29, -0.20], Z = 2.67, P = 0.008). CONCLUSION: A reduction in 5-HT1A binding in the hippocampus, temporal cortex, amygdala, and frontal lobe was observed on the affected side of patients with TLE. The decrease in 5-HT1A binding can be considered related to TLE. Potentially relevant factors should be considered in future molecular imaging studies.


Asunto(s)
Epilepsia del Lóbulo Temporal , Humanos , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/metabolismo , Hipocampo/metabolismo , Imagen por Resonancia Magnética/métodos , Convulsiones/metabolismo , Lóbulo Temporal/metabolismo
12.
Angew Chem Int Ed Engl ; 62(23): e202302152, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-36972027

RESUMEN

We report a ternary hybrid photocatalyst architecture with tailored interfaces that boost the utilization of solar energy for photochemical CO2 reduction by synergizing electron and heat flows in the photocatalyst. The photocatalyst comprises cobalt phthalocyanine (CoPc) molecules assembled on multiwalled carbon nanotubes (CNTs) that are decorated with nearly monodispersed cadmium sulfide quantum dots (CdS QDs). The CdS QDs absorb visible light and generate electron-hole pairs. The CNTs rapidly transfer the photogenerated electrons from CdS to CoPc. The CoPc molecules then selectively reduce CO2 to CO. The interfacial dynamics and catalytic behavior are clearly revealed by time-resolved and in situ vibrational spectroscopies. In addition to serving as electron highways, the black body property of the CNT component can create local photothermal heating to activate amine-captured CO2 , namely carbamates, for direct photochemical conversion without additional energy input.

13.
Clin Chem ; 68(2): 332-343, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-34942001

RESUMEN

BACKGROUND: Although major advances have been made in the histopathological diagnosis of high-grade astrocytoma (HGA), methods for effective and noninvasive diagnosis remain largely unknown. Exosomes can cross the blood-brain barrier and are readily accessible in human biofluids, making them promising biomarkers for HGA. Circular RNAs (circRNAs) have potential as tumor biomarkers owing to their stability, conservation, and tissue specificity. However, the landscape and characteristics of exosome circRNAs in HGA remain to be studied. METHODS: CircRNA deep sequencing and bioinformatics approaches were used to generate a circRNA profiling database and analyze the features of HGA cell circRNAs and HGA cell-derived exosome circRNAs. Exosome circRNA expression in the serum and tissues of healthy individuals and patients with HGA was detected using reverse transcription-quantitative PCR. Additionally, the receiver operating characteristic curve and overall survival curves were analyzed. RESULTS: By investigating the characteristics of HGA cell-derived exosome circRNAs and HGA cell circRNAs, we observed that exosomes were more likely to enrich short-exon and suppressor circRNAs than HGA cells. Moreover, a serum exosome circRNA panel including hsa_circ_0075828, hsa_circ_0003828, and hsa_circ_0002976 could be used to screen for HGA, whereas a good prognosis panel comprised high concentrations of hsa_circ_0005019, hsa_circ_0000880, hsa_circ_0051680, and hsa_circ_0006365. CONCLUSIONS: This study revealed a comprehensive circRNA landscape in HGA exosomes and cells. The serum exosome circexosome circRNA panel and tissue circRNAs are potentially useful for HGA liquid biopsy and prognosis monitoring. Exosome circRNAs as novel targets should facilitate further biomarker discovery and aid in HGA diagnosis and therapy monitoring.


Asunto(s)
Astrocitoma , Exosomas , Astrocitoma/diagnóstico , Astrocitoma/genética , Biomarcadores de Tumor/genética , Exosomas/genética , Humanos , ARN/genética , ARN Circular/genética , Análisis de Secuencia de ARN
14.
Acc Chem Res ; 54(1): 70-80, 2021 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-33141563

RESUMEN

The semiconductor-nanocrystal-sensitized, three-component upconversion system has made great strides over the past 5 years. The three components (i.e., triplet photosensitizer, mediator, and emitter) each play critical roles in determining the input and output photon energy and overall quantum efficiency (QE). The nanocrystal photosensitizer converts the absorbed photon into singlet excitons and then triplet excitons via intersystem crossing. The mediator accepts the triplet exciton via either direct Dexter-type triplet energy transfer (TET) or sequential charge transfer (CT) while extending the exciton lifetime. Through a second triplet energy-transfer step from the mediator to the emitter, the latter is populated in its lowest excited triplet state. Triplet-triplet annihilation (TTA) between two triplet emitters generates the emitter in its bright singlet state, which then emits the upconverted photon. Quantum dots (QD) have a tunable band gap, large extinction coefficient, and small singlet-triplet energy losses compared to metal-ligand charge-transfer complexes. This high triplet exciton yield makes QDs good candidates for photosensitizers. In terms of driving triplet energy transfer, the triplet energy of the mediator should be slightly lower than the triplet exciton energy of the QD sensitizer for a downhill energy landscape with minimal energy loss. The same energy cascade is also required for the transfer from the mediator to the emitter. Finally, the triplet energy of the emitter must be slightly larger than one-half of its singlet energy to ensure that TTA is exothermic. Optimization of the sensitizer, mediator, and emitter will lead to an increase in the anti-Stokes shift and the total quantum efficiency. Evaluating each individual step's efficiency and kinetics is necessary for the understanding of the limiting factors in existing systems.This review summarizes chalcogenide QD-based photon upconversion systems with a focus on the mechanistic aspects of triplet energy transfer conducted by the Tang and Lian groups. Via time-resolved spectroscopy, the rates and major loss pathways associated with the two triplet energy-transfer steps were identified. The studies are focused on the near-infrared (NIR) to visible (VIS) PbS-tetracene-based systems as they allow systematic control of the QD, mediator, and emitter. Our results show that the mediator triplet state is mostly formed by direct TET from the QD and the transfer rate is influenced by the density of bound mediator molecules. Charge transfer, a loss pathway, does not produce triplet excitons and can be minimized by adding an inert shell to the QD. This transfer rate decreases exponentially with the distance between the QD and mediator molecule. The second TET rate was found to be much slower than the diffusion-limited collision rate, which results in the triplet lifetime of the mediator being the main factor limiting its efficiency. Finally, the total quantum efficiency can be calculated using these measured quantities including the TET1 and TET2 efficiencies. The agreement between calculated and measured quantum efficiencies suggests a firm understanding of QD-sensitized photon upconversion. We believe the above conclusions are general and should be widely applicable to similar systems, including singlet fission in hybrid organic-nanocrystal materials.

15.
Chem Soc Rev ; 50(22): 12679-12701, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34636824

RESUMEN

The past few decades have seen emerging growth in the field of soft materials for synthetic biology. This review focuses on soft materials involved in biological and artificial membranes. The biological membranes discussed here are mainly those involved in the structure and function of cells and organelles. As building blocks in medicine, non-native membranes including nanocarriers (NCs), especially liposomes and DQAsomes, and polymeric membranes for scaffolds are constructed from amphiphilic combinations of lipids, proteins, and carbohydrates. Artificial membranes can be prepared using synthetic, soft materials and molecules and then incorporated into structures through self-organization to form micelles or niosomes. The modification of artificial membranes can be realized using traditional chemical methods such as click reactions to target the delivery of NCs and control the release of therapeutics. The biomembrane, a lamellar structure inlaid with ion channels, receptors, lipid rafts, enzymes, and other functional units, separates cells and organelles from the environment. An active domain inserted into the membrane and organelles for energy conversion and cellular communication can target disease by changing the membrane's composition, structure, and fluidity and affecting the on/off status of the membrane gates. The biological membrane targets analyzing pathological mechanisms and curing complex diseases, which inspires us to create NCs with artificial membranes.


Asunto(s)
Membrana Dobles de Lípidos , Membranas Artificiales , Membrana Celular , Liposomas , Polímeros
16.
Sensors (Basel) ; 22(17)2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-36081164

RESUMEN

Aiming at the problems of nonlinearity and inaccuracy in the model of the pneumatic control valve position in the industrial control process, a valve position control method based on a fractional-order PID controller is proposed. The working principle of the pneumatic control valve is analyzed, and its mathematical model is established. In order to improve the accuracy of the model, an improved biogeography-based optimization algorithm is proposed to tune the parameters of the fractional-order PID controller in view of the wide range and high complexity of the fractional-order PID controller. The initialization of the chaotic graph, the adjustment of the migration model, and the improvement of the migration operator and the mutation operator are introduced to improve the algorithm optimization ability, which is used for the model identification of the control valve control system. The simulation and experimental results clearly show that, compared with the integer-order PID controller, the designed fractional-order PID controller has faster response speed and control accuracy, which can better meet the requirements of pneumatic control valve position control.

17.
Nano Lett ; 21(19): 8017-8024, 2021 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-34569798

RESUMEN

Nanoscale oxide layer protected semiconductor photoelectrodes show enhanced stability and performance for solar fuels generation, although the mechanism for the performance enhancement remains unclear due to a lack of understanding of the microscopic interfacial field and its effects. Here, we directly probe the interfacial fields at p-GaP electrodes protected by n-TiO2 and its effect on charge carriers by transient reflectance spectroscopy. Increasing the TiO2 layer thickness from 0 to 35 nm increases the field in the GaP depletion region, enhancing the rate and efficiency of interfacial electron transfer from the GaP to TiO2 on the ps time scale as well as retarding interfacial recombination on the microsecond time scale. This study demonstrates a general method for providing a microscopic view of the photogenerated charge carrier's pathway and loss mechanisms from the bulk of the electrode to the long-lived separated charge at the interface that ultimately drives the photoelectrochemical reactions.


Asunto(s)
Óxidos , Titanio , Electrodos , Luz Solar
18.
J Am Chem Soc ; 143(24): 8987-8992, 2021 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-34102836

RESUMEN

We developed an effective method for reductive radical formation that utilizes the radical anion of carbon dioxide (CO2•-) as a powerful single electron reductant. Through a polarity matched hydrogen atom transfer (HAT) between an electrophilic radical and a formate salt, CO2•- formation occurs as a key element in a new radical chain reaction. Here, radical chain initiation can be performed through photochemical or thermal means, and we illustrate the ability of this approach to accomplish reductive activation of a range of substrate classes. Specifically, we employed this strategy in the intermolecular hydroarylation of unactivated alkenes with (hetero)aryl chlorides/bromides, radical deamination of arylammonium salts, aliphatic ketyl radical formation, and sulfonamide cleavage. We show that the reactivity of CO2•- with electron-poor olefins results in either single electron reduction or alkene hydrocarboxylation, where substrate reduction potentials can be utilized to predict reaction outcome.


Asunto(s)
Dióxido de Carbono/química , Aniones/química , Radicales Libres/química , Estructura Molecular , Oxidación-Reducción
19.
World J Urol ; 39(4): 1277-1285, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32448970

RESUMEN

OBJECTIVE: To evaluate the role of stone components in postoperative fever following RIRS, and to investigate the role of quick stone component analysis during RIRS procedure. PATIENTS AND METHODS: 1493 patients with RIRS were retrospectively reviewed. Propensity score matching (PSM) analysis was performed as infection stones (IS) vs. calcium-containing stones (CS) and IS vs. other compositions (OS). Independent risk factors of postoperative fever were identified by logistic analysis and nomogram was constructed. RESULTS: A total of 73 patients suffered postoperative fever (4.9%), 8 patients with sepsis (0.5%), 4 patients with septic shock (0.3%). In IS vs. CS, the incidence of positive urine test (28.4% vs. 14.7%, p = 0.001), residual stone (48.2% vs. 37.6%, p = 0.04), and postoperative fever (9.1% vs. 2.0%, p = 0.004) was significantly higher in IS. In IS vs. OS, IS had a higher incidence of positive urine test (30.9% vs. 9.3%, p < 0.001) and residual stone (47.4% vs. 18.6%, p < 0.001), while there was no significant difference in postoperative fever (10.3% vs. 4.1%, p = 0.17). Multivariate regression analysis revealed that gender (OR 1.82, CI 1.09-3.07, p < 0.001), stone components (OR 0.6, CI 0.37-0.97, p = 0.038), urine test (OR 3.72, CI 2.23-6.20, p < 0.001), and neutrophil ratio > 75% (OR 5.17, CI 3.03-9.16, p < 0.001) were independent risk factors for postoperative fever. A nomogram with moderate discriminative ability (c-index: 0.813) was constructed to predict postoperative fever. CONCLUSION: Infection stones were closely associated with postoperative fever following RIRS, as well as female gender, preoperative positive urine test, and postoperative neutrophil ratio > 75%. A quick stone component analysis would help in prevention of infectious complications. Early and longer duration of antimicrobial therapy was recommended for patients with infection stones.


Asunto(s)
Fiebre/epidemiología , Cálculos Renales/química , Cálculos Renales/cirugía , Complicaciones Posoperatorias/epidemiología , Infecciones Urinarias/epidemiología , Adulto , Femenino , Humanos , Riñón/cirugía , Masculino , Persona de Mediana Edad , Puntaje de Propensión , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Procedimientos Quirúrgicos Urológicos
20.
J Infect Chemother ; 27(2): 323-328, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33309627

RESUMEN

PURPOSE: We aimed to compare the efficacy of percutaneous nephrostomy (PCN) versus retrograde ureteric stent (RUS) for acute upper urinary tract obstruction with urosepsis. MATERIALS AND METHODS: We performed a random study, comparing PCN to RUS, for the treatment of patients requiring emergency drainage due to acute upper urinary tract obstruction with urosepsis between January 2019 to March 2020. Data collected included patient characteristics, stone material, microbiological characteristics, and laboratory data. Statistical analysis was performed by the student's t-test or Mann-Whitney U test or chi-squared test and Fisher exact test. RESULTS: At first, a total of 75 patients were eligibly assessed for enrollment. Among them, 3 cases were excluded for declining to participate and 7 cases were failed treated with RUS. At last, 35 PCN (53.85%) and 30 RUS (46.15%) patients were analyzed. There were 24 (36.92%) men and 41 (63.08%) women. The median age was 65 years. Emergency decompression was achieved by PCN in 35 (53.85%) patients and by RUS in 30 (46.15%). Urine culture was positive in 32 (49.23%) patients, of which 17 (53.13%) had E. coli. Postoperative C-reactive protein value and normal temperature recovery time in the PCN group were significantly lower than in the RUS group(P < .05). CONCLUSION: PCN had a better outcome than RUS in emergency drainage with urosepsis, especially for patients with severe inflammation and fever.


Asunto(s)
Nefrostomía Percutánea , Obstrucción Ureteral , Anciano , Escherichia coli , Femenino , Humanos , Masculino , Stents , Obstrucción Ureteral/cirugía
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