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1.
J Colloid Interface Sci ; 675: 326-335, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38972120

RESUMO

Water splitting is a promising technique for clean hydrogen production. To improve the sluggish hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), the development of efficient bifunctional electrocatalysts for both HER and OER is urgent to approach the scale-up applications of water splitting. Nowadays transition metal oxides (TMOs) are considered as the promising electrocatalysts due to their low cost, structural flexibility and stability, however, their electrocatalytic activities are eager to be improved. Here, we synthesized waxberry-like hydrophilic Co-doped ZnFe2O4 electrocatalysts as bifunctional electrocatalysts for water splitting. Due to the enhanced active sites by electronic structure tuning and modified super-hydrophilic characteristics, the spinel ZFO-Co0.5 electrocatalyst exhibits excellent catalytic activities for both OER and HER. It exhibits a remarkable low OER overpotential of 220 mV at a current density of 10 mA cm-2 and a Tafel slope of 28.2 mV dec-1. Meanwhile, it achieves a low overpotential of 73 mV at a current density of 10 mA cm-2 with the Tafel slope of 87 mV dec-1 for HER. In addition, for water electrolysis device, the electrocatalytic performance of ZFO-Co0.5||ZFO-Co0.5 surpasses that of commercial IrO2||Pt/C. Our work reveals that the hydrophilic morphology regulation combined with metallic doping strategy is a facile and effective approach to synthesize spinel TMOs as excellent bifunctional electrocatalyst for water splitting.

2.
Anal Chem ; 96(28): 11603-11610, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38953495

RESUMO

Long noncoding RNAs (lncRNAs) act as the dynamic regulatory molecules that control the expression of genes and affect numerous biological processes, and their dysregulation is associated with tumor progression. Herein, we develop a fluorescent light-up aptasensor to simultaneously measure multiple lncRNAs in living cells and breast tissue samples based on the DNAzyme-mediated cleavage reaction and transcription-driven synthesis of light-up aptamers. When target lncRNAs are present, they can be recognized by template probes to form the active DNAzyme structures, initiating the T4 PNK-catalyzed dephosphorylation-triggered extension reaction to generate double-strand DNAs with the T7 promoter sequences. The corresponding T7 promoters can initiate the transcription amplification catalyzed by the T7 RNA polymerase to generate abundant Broccoli aptamers and malachite green aptamers, which can bind DFHBI-1T and MG to generate strong fluorescence signals. Taking advantage of the good selectivity of DNAzyme-mediated cleavage of lncRNAs, high amplification efficiency of T7 transcription-driven amplification reaction, and bright fluorescence of the RNA aptamer-fluorophore complex, this method exhibits high sensitivity with a detection limit of 21.4 aM for lncRNA HOTAIR and 18.47 aM for lncRNA MALAT1, and it can accurately measure multiple lncRNAs in both tumor cell lines and breast tissue samples, providing a powerful paradigm for biomedical research and early clinic diagnostics.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , DNA Catalítico , Corantes Fluorescentes , RNA Longo não Codificante , DNA Catalítico/química , DNA Catalítico/metabolismo , RNA Longo não Codificante/análise , RNA Longo não Codificante/metabolismo , RNA Longo não Codificante/genética , Humanos , Aptâmeros de Nucleotídeos/química , Corantes Fluorescentes/química , Limite de Detecção , Fluorescência
3.
Infect Drug Resist ; 17: 2823-2832, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39005857

RESUMO

Introduction: Recent studies suggested the potential benefits of extended infusion times to optimize the treatment efficacy of ceftazidime/avibactam, which indicated that the current pharmacokinetic/pharmacodynamic (PK/PD) target may not be sufficient, especially for severe infections. The purpose of this study is to assess the adequacy of dosing strategies and infusion durations of ceftazidime/avibactam when applying higher PK/PD targets. Methods: This study utilized published PK parameters to conduct Monte Carlo simulations. Different dosages including the recommended regimen based on renal function were simulated and evaluated by the probability of target attainment (PTA) and cumulative fraction of response (CFR). Different PK/PD targets were set for ceftazidime and avibactam. MIC distributions from various sources were used to calculate the CFR. Results: Multiple PK/PD targets have been set in this study, All recommended dosage could easily achieve the target of 50%fT ≥ MIC (ceftazidime) and 50%fT ≥ CT=1.0 mg/L (avibactam). However, for severe infection patients with normal renal function and augmented renal clearance at the recommended dosage (2000 mg/500 mg, every 8 hours), the infusion duration needs to be extended to 3 hours and 4 hours to achieve the targets of 100%fT ≥ MIC and 100%fT ≥ CT=1.0 mg/L. Only continuous infusion at higher dosages achieved 100%fT ≥ 4×MIC and 100%fT ≥ CT=4.0 mg/L targets to all currently recommended regimens. According to the varying MIC distributions, higher concentrations are needed for Pseudomonas aeruginosa, with the attainment rates vary across different regions. Conclusion: The current recommended dosing regimen of ceftazidime/avibactam is insufficient for severe infection patients, and continuous infusion is suggested.

4.
Ecol Evol ; 14(7): e70013, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39011133

RESUMO

Amaranthaceae s.l. is a widely distributed family consisting of over 170 genera and 2000 species. Previous molecular phylogenetic studies have shown that Amaranthaceae s.s. and traditional Chenopodiaceae form a monophyletic group (Amaranthaceae s.l.), however, the relationships within this evolutionary branch have yet to be fully resolved. In this study, we assembled the complete plastomes and full-length ITS of 21 Amaranthaceae s.l. individuals and compared them with 38 species of Amaranthaceae s.l. Through plastome structure and sequence alignment analysis, we identified a reverse complementary region approximately 5200 bp long in the genera Atriplex and Chenopodium. Adaptive evolution analysis revealed significant positive selection in eight genes, which likely played a driving role in the evolution of Amaranthaceae s.l., as demonstrated by partitioned evolutionary analysis. Furthermore, we found that about two-thirds of the examined species lack the ycf15 gene, potentially associated with natural selection pressures from their adapted habitats. The phylogenetic tree indicated that some genera (Chenopodium, Halogeton, and Subtr. Salsolinae) are paraphyletic lineages. Our results strongly support the clustering of Amaranthaceae s.l. with monophyletic traditional Chenopodiaceae (Clades I and II) and Amaranthaceae s.s. After a comprehensive analysis, we determined that cytonuclear conflict, gene selection by adapted habitats, and incomplete lineage sorting (ILS) events were the primary reasons for the inconsistent phylogeny of Amaranthaceae s.l. During the last glacial period, certain species within Amaranthaceae s.l. underwent adaptations to different environments and began to differentiate rapidly. Since then, these species may have experienced morphological and genetic changes distinct from those of other genera due to intense selection pressure.

5.
Sci Total Environ ; 948: 174836, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39029761

RESUMO

The United Nations Sustainable Development Goals call for innovative proposals to ensure access to clean water and sanitation. While significant strides have been made in enhancing drinking water purification technologies, the role of drinking water distribution systems (DWDS) in maintaining water quality safety has increasingly become a focal point of concern. The presence of scale within DWDS can impede the secure and efficient functioning of the drinking water supply system, posing risks to the safety of drinking water quality. Previous research has identified that the primary constituents of scale in DWDS are insoluble minerals, such as calcium and magnesium carbonate. Elevated levels of hardness and alkalinity in the water can exacerbate scale formation. To address the scaling issue, softening technologies like induced crystallization, nanofiltration/reverse osmosis, and ion exchange are currently in widespread use. These methods effectively mitigate the scaling in DWDS by reducing the water's hardness and alkalinity. However, the application of softening technologies not only alters the hardness and alkalinity but also induces changes in the fundamental characteristics of water quality, leading to transition effects within the DWDS. This article reviews the impact of various softening technologies on the intrinsic properties of water quality and highlights the merits of electrochemical characteristic indicators in the assessment of water quality stability. Additionally, the paper delves into the factors that influence the transition effects in DWDS. It concludes with a forward-looking proposal to leverage artificial intelligence, specifically machine learning and neural networks, to develop an evaluation and predictive framework for the stability of drinking water quality and the transition effects observed in DWDS. This approach aims to provide a more accurate and proactive method for managing and predicting the impacts of water treatment processes on distribution system integrity and water quality over time.

6.
Microbiol Res ; 285: 127774, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38833829

RESUMO

Extended-spectrumß-lactam producing Escherichia coli (ESBL-EC) readily colonizes live poultry and serves as a major source of contamination in retail chicken meat, posing significant threats to public health. This study aims to investigate the impact of inappropriate antibiotic use on the dissemination and exacerbation of antibiotic resistance in ESBL-EC and explore the underlying molecular mechanisms. Through experimental analysis, we propose a hypothesis that inappropriate antibiotic use may exacerbate resistance by affecting vesicle formation and protein secretion. Experimental results demonstrate that under the influence of amoxicillin, the concentration of proteins secreted in outer membrane vehicles (OMVs) by ESBL-EC significantly increases, along with a significant upregulation in the expression of the CTX-M-55-type Extended-spectrum beta-lactamase (CTX-M-55). Proteomic analysis and differential gene knockout experiments identified the key protein YdcZ, associated with OMVs formation and protein transportation in ESBL-EC under amoxicillin treatment. Further investigations reveal direct interactions between YdcZ and other proteins (YdiH and BssR). Upon ydcz gene knockout, a significant decrease in protein concentration within OMVs is observed, accompanied by a noticeable reduction in protection against sensitive bacteria. These findings suggest a critical role of YdcZ in regulating the process of protein transportation to OMVs in ESBL-EC under the influence of amoxicillin. In summary, our research uncovers the significant role of inappropriate antibiotic use in promoting the secretion of OMVs by ESBL-EC, aiding the survival of antibiotic-sensitive bacteria in the vicinity of infection sites. These findings provide new insights into the mechanisms underlying antibiotic-induced bacterial resistance dissemination and offer novel avenues for exploring prevention and control strategies against bacterial resistance propagation.


Assuntos
Amoxicilina , Antibacterianos , Proteínas de Escherichia coli , Escherichia coli , Transporte Proteico , beta-Lactamases , Antibacterianos/farmacologia , Escherichia coli/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , beta-Lactamases/metabolismo , beta-Lactamases/genética , Amoxicilina/farmacologia , Animais , Testes de Sensibilidade Microbiana , Proteômica , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas da Membrana Bacteriana Externa/genética , Galinhas/microbiologia , Farmacorresistência Bacteriana , Membrana Externa Bacteriana/efeitos dos fármacos , Membrana Externa Bacteriana/metabolismo , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/tratamento farmacológico
7.
Gerontologist ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38943547

RESUMO

BACKGROUND AND OBJECTIVES: This study examined the psychometric properties and measurement invariance of the 10-item Awareness of Age-Related Change Short Form (AARC-SF) questionnaire in a Chinese-speaking sample of older adults in Taiwan. RESEARCH DESIGN AND METHODS: Data from 292 participants (Mage = 77.64 years) in the Healthy Aging Longitudinal Study in Taiwan (HALST) cohort were used for Study 1, whereas data from young-old adult samples in Germany were used for Study 2. RESULTS: Study 1 showed that the AARC-SF had satisfactory reliability and validity for assessing adults' AARC in Taiwan. Analyses confirmed the two-factor structure of AARC-gains and AARC-losses. Study 2 demonstrated strong measurement invariance across men and women, whereas direct comparisons of the item scores between young-old adults and old-old adults need to be made with caution. Non-invariance of loadings indicated that certain items were more closely linked to AARC-gains and AARC-losses in Taiwan than in Germany. Non-invariance of intercepts suggested potential biases in comparing item scores between Taiwanese and German older adults. DISCUSSION AND IMPLICATIONS: The AARC-SF emerged as a reliable and valid instrument for capturing positive and negative subjective aging experiences among Taiwanese older adults. However, it is noteworthy that some items on the AARC-SF may solicit different responses from individuals of different ages and different countries of origin, requiring caution with age group and cross-cultural comparisons.

8.
Lab Chip ; 24(14): 3422-3433, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38860416

RESUMO

Thrombosis, characterized by blood clot formation within vessels, poses a significant medical challenge. Despite extensive research, the development of effective thrombosis therapies is hindered by substantial costs, lengthy development times, and high failure rates in medication commercialization. Conventional pre-clinical models often oversimplify cardiovascular disease, leading to a disparity between experimental results and human physiological responses. In response, we have engineered a photothrombosis-on-a-chip system. This microfluidic model integrates human endothelium, human whole blood, and blood flow dynamics and employs the photothrombotic method. It enables precise, site-specific thrombus induction through controlled laser irradiation, effectively mimicking both normal and thrombotic physiological conditions on a single chip. Additionally, the system allows for the fine-tuning of thrombus occlusion levels via laser parameter adjustments, offering a flexible thrombus model with varying degrees of obstruction. Additionally, the formation and progression of thrombosis noted on the chip closely resemble the thrombotic conditions observed in mice in previous studies. In the experiments, we perfused recalcified whole blood with Rose Bengal into an endothelialized microchannel and initiated photothrombosis using green laser irradiation. Various imaging methods verified the model's ability to precisely control thrombus formation and occlusion levels. The effectiveness of clinical drugs, including heparin and rt-PA, was assessed, confirming the chip's potential in drug screening applications. In summary, the photothrombosis-on-a-chip system significantly advances human thrombosis modeling. Its precise control over thrombus formation, flexibility in the thrombus severity levels, and capability to simulate dual physiological states on a single platform make it an invaluable tool for targeted drug testing, furthering the development of organ-on-a-chip drug screening techniques.


Assuntos
Dispositivos Lab-On-A-Chip , Trombose , Humanos , Lasers , Técnicas Analíticas Microfluídicas/instrumentação , Animais , Rosa Bengala
9.
Sci Rep ; 14(1): 11486, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769368

RESUMO

The purpose of this study was to investigate the relationship between circulating cytokines and liver function and prognosis of patients with advanced hepatocellular carcinoma (HCC) treated with radiotherapy combined with tislelizumab and anlotinib. The liver function indexes and pre-treatment levels of cytokines in 47 patients were measured by chemical method and flow cytometry. The median follow-up was 23.1 months. The objective response and the disease control rates were 46.8% and 68.1%, while overall survival (OS) and progression-free survival (PFS) were 12.6 and 11.4 months, respectively. Adverse events (2.1%) were grade 3-4. In addition to stage, intrahepatic metastasis and Child-Pugh score, pre-treatment interleukin-6 (IL-6) was the main cytokine affecting OS and PFS (p < 0.05). The OS (14.63 pg/mL as cutoff value) and PFS (9.85 pg/mL as cutoff value) of patients with low IL-6 levels exceeded those with high levels (21.0 and 6.9, 15.8 and 10.0 months, respectively). The risks of death and disease progression were reduced by 63.0% (HR = 0.37, 95% CI: 0.19-0.72) and 43.0% (HR = 0.57, 95% CI: 0.22-1.47), respectively. Pre-treatment IL-6 levels may be a simple and effective prognostic indicator for patients with advanced HCC treated with radiotherapy combined with immunotargeted therapy.


Assuntos
Anticorpos Monoclonais Humanizados , Carcinoma Hepatocelular , Citocinas , Indóis , Neoplasias Hepáticas , Quinolinas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/radioterapia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Quinolinas/uso terapêutico , Quinolinas/administração & dosagem , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Idoso , Indóis/uso terapêutico , Indóis/administração & dosagem , Prognóstico , Citocinas/sangue , Adulto , Interleucina-6/sangue , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
10.
Phys Chem Chem Phys ; 26(23): 16664-16673, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38808589

RESUMO

For the conversion of fructose/methylglucoside (MG) into both methyl formate (MF) and methyl levulinate (MLev), the C-source of formate [HCOO]- remains unclear at the molecular level. Herein, reaction mechanisms catalyzed by [CH3OH2]+ in a methanol solution were theoretically investigated at the PBE0/6-311++G(d,p) level. For the conversion of fructose into MF and MLev, the formate [HCOO]- comes from the C1-atom of fructose, in which the rate-determining step lies in the reaction of 5-hydroxymethylfurfural (HMF) with CH3OH to yield MF and MLev. The reaction of fructose with CH3OH kinetically tends to generate HMF intermediates rather than yield (MF + MLev). When MG is dissolved in a methanol solution, its O2, O3, and O4 atoms are closer to the first layer of the solvent than O1, O5, and O6 atoms. For the dehydration of MG with methanol into MF and MLev, the formate [HCOO]- stems from the dominant C1- and secondary C3-atoms of MG. Kinetically, MG is ready to yield (MF + MLev), whereas fructose can induce the reaction to remain at the HMF intermediate, inhibiting the further conversion of HMF with CH3OH into MF and MLev. If MG isomerizes into fructose, the reaction will be more preferable for yielding HMF rather than (MF + MLev).

11.
Small ; : e2401447, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38693087

RESUMO

Topological defects are widely recognized as effective active sites toward a variety of electrochemical reactions. However, the role of defect curvature is still not fully understood. Herein, carbon nanomaterials with rich topological defect sites of tunable curvature is reported. The curved defective surface is realized by controlling the high-temperature pyrolytic shrinkage process of precursors. Theoretical calculations demonstrate bending the defect sites can change the local electronic structure, promote the charge transfer to key intermediates, and lower the energy barrier for oxygen reduction reaction (ORR). Experimental results convince structural superiority of highly-curved defective sites, with a high kinetic current density of 22.5 mA cm-2 at 0.8 V versus RHE for high-curvature defective carbon (HCDC), ≈18 times that of low-curvature defective carbon (LCDC). Further raising the defect densities in HCDC leads to the dual-regulated products (HCHDC), which exhibit exceptionally outstanding ORR activity in both alkaline and acidic media (half-wave potentials: 0.88 and 0.74 V), outperforming most of the reported metal-free carbon catalysts. This work uncovers the curvature-activity relationship in carbon defect for ORR and provides new guidance to design advanced catalysts via curvature-engineering.

12.
Int J Med Sci ; 21(6): 1117-1128, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774761

RESUMO

In this study, we developed a microfluidic device that is able to monitor cell biology under continuous PM2.5 treatment. The effects of PM2.5 on human alveolar basal epithelial cells, A549 cells, and uncovered several significant findings were investigated. The results showed that PM2.5 exposure did not lead to a notable decrease in cell viability, indicating that PM2.5 did not cause cellular injury or death. However, the study found that PM2.5 exposure increased the invasion and migration abilities of A549 cells, suggesting that PM2.5 might promote cell invasiveness. Results of RNA sequencing revealed 423 genes that displayed significant differential expression in response to PM2.5 exposure, with a particular focus on pathways associated with the generation of reactive oxygen species (ROS) and mitochondrial dysfunction. Real-time detection demonstrated an increase in ROS production in A549 cells after exposure to PM2.5. JC1 assay, which indicated a loss of mitochondrial membrane potential (ΔΨm) in A549 cells exposed to PM2.5. The disruption of mitochondrial membrane potential further supports the detrimental effects of PM2.5 on A549 cells. These findings highlight several adverse effects of PM2.5 on A549 cells, including enhanced invasion and migration capabilities, altered gene expression related to ROS pathways, increased ROS production and disruption of mitochondrial membrane potential. These findings contribute to our understanding of the potential mechanisms through which PM2.5 can impact cellular function and health.


Assuntos
Movimento Celular , Sobrevivência Celular , Neoplasias Pulmonares , Potencial da Membrana Mitocondrial , Material Particulado , Espécies Reativas de Oxigênio , Humanos , Material Particulado/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo , Células A549 , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Movimento Celular/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dispositivos Lab-On-A-Chip , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Invasividade Neoplásica/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Microfluídica/métodos
13.
Phys Chem Chem Phys ; 26(20): 14613-14623, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38739028

RESUMO

A Ru-containing complex shows good catalytic performance toward the hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) with the assistance of organic base ligands (OBLs) and CO2. Herein, we report the competitive mechanisms for the hydrogenation of LA to GVL, 4-oxopentanal (OT), and 2-methyltetrahydro-2,5-furandiol (MFD) with HCOOH or H2 as the H source catalyzed by RuCl3 in aqueous solution at the M06/def2-TZVP, 6-311++G(d,p) theoretical level. Kinetically, the hydrodehydration of LA to GVL is predominant, with OT and MFD as side products. With HCOOH as the H source, initially, the OBL (triethylamine, pyridine, or triphenylphosphine) is responsible for capturing H+ from HCOOH, leading to HCOO- and [HL]+. Next, the Ru3+ site is in charge of sieving H- from HCOO-, yielding [RuH]2+ hydride and CO2. Alternatively, with H2 as the H source, the OBL stimulates the heterolysis of H-H bond with the aid of Ru3+ active species, producing [RuH]2+ and [HL]+. Toward the [RuH]2+ formation, H2 as the H source exhibits higher activity than HCOOH as the H source in the presence of an OBL. Thereafter, H- in [RuH]2+ gets transferred to the unsaturated C site of ketone carbonyl in LA. Afterwards, the Ru3+ active species is capable of cleaving the C-OH bond in 4-hydroxyvaleric acid, yielding [RuOH]2+ hydroxide and GVL. Subsequently, CO2 promotes Ru-OH bond cleavage in [RuOH]2+, forming HCO3- and regenerating the Ru3+-active species owing to its Lewis acidity. Lastly, between the resultant HCO3- and [HL]+, a neutralization reaction occurs, generating H2O, CO2, and OBLs. Thus, the present study provides insights into the promotive roles of additives such as CO2 and OBLs in Ru-catalyzed hydrogenation.

14.
Anal Chem ; 96(19): 7738-7746, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38690966

RESUMO

Telomerase is an important biomarker for early diagnosis of cancers, but current telomerase assays usually rely on measuring the extension products of telomerase substrates, which increases the assay complexity. More evidence indicates that human telomerase RNA (hTR), as a core component of telomerase, is positively correlated with the telomerase activity. Herein, we demonstrate the development of a duplex-specific nuclease (DSN)-propelled 3D quantum dot (QD) nanoassembly with two-step Föster resonance energy transfer (FRET) for the one-step sensing of hTR in breast cancer cells and tissues. This assay involves only one hairpin probe modified with a Cy5 at the sixth base from the 5'-biotin end and a BHQ2 at the 3'-terminus, which integrates three functions of target recognition, target recycling amplification, and signal readout. The anchoring of the hairpin probe on the 605QD surface results in the formation of a 3D 605QD-Cy5-probe-BHQ2 nanoassembly in which two-step FRET occurs among the 605QD, Cy5, and BHQ2 quencher. Notably, the formation of 605QD-Cy5-probe-BHQ2 nanoassembly facilitates the reduction of background signal and the increase of signal-to-background ratio due to its dense, highly oriented nucleic acid shell-induced steric hindrance effect. This assay can achieve one-step and rapid detection of hTR with a detection limit of 2.10 fM, which is the simplest and most rapid hTR assay reported so far. Moreover, this assay can efficiently distinguish single-base mismatched sequences, and it can discriminate the hTR level between breast cancer patients and healthy donors with a high accuracy of 100%, with great prospects for early diagnosis of cancers.


Assuntos
Neoplasias da Mama , Transferência Ressonante de Energia de Fluorescência , Pontos Quânticos , RNA , Telomerase , Humanos , Telomerase/metabolismo , Telomerase/análise , Pontos Quânticos/química , RNA/metabolismo , RNA/análise , Feminino , Carbocianinas/química , Técnicas Biossensoriais/métodos
15.
J Nanobiotechnology ; 22(1): 290, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802884

RESUMO

Corneal neovascularization (CNV) is one of the common blinding factors worldwide, leading to reduced vision or even blindness. However, current treatments such as surgical intervention and anti-VEGF agent therapy still have some shortcomings or evoke some adverse effects. Recently, SU6668, an inhibitor targeting angiogenic tyrosine kinases, has demonstrated growth inhibition of neovascularization. But the hydrophobicity and low ocular bioavailability limit its application in cornea. Hereby, we proposed the preparation of SU6668 pure nanoparticles (NanoSU6668; size ~135 nm) using a super-stable pure-nanomedicine formulation technology (SPFT), which possessed uniform particle size and excellent aqueous dispersion at 1 mg/mL. Furthermore, mesenchymal stem cell membrane vesicle (MSCm) was coated on the surface of NanoSU6668, and then conjugated with TAT cell penetrating peptide, preparing multifunctional TAT-MSCm@NanoSU6668 (T-MNS). The T-MNS at a concentration of 200 µg/mL was treated for CNV via eye drops, and accumulated in blood vessels with a high targeting performance, resulting in elimination of blood vessels and recovery of cornea transparency after 4 days of treatment. Meanwhile, drug safety test confirmed that T-MNS did not cause any damage to cornea, retina and other eye tissues. In conclusion, the T-MNS eye drop had the potential to treat CNV effectively and safely in a low dosing frequency, which broke new ground for CNV theranostics.


Assuntos
Córnea , Neovascularização da Córnea , Nanopartículas , Soluções Oftálmicas , Neovascularização da Córnea/tratamento farmacológico , Animais , Nanopartículas/química , Soluções Oftálmicas/química , Córnea/metabolismo , Córnea/efeitos dos fármacos , Camundongos , Inibidores da Angiogênese/química , Inibidores da Angiogênese/uso terapêutico , Inibidores da Angiogênese/farmacologia , Tamanho da Partícula , Humanos , Masculino , Camundongos Endogâmicos C57BL , Coelhos
16.
World J Psychiatry ; 14(5): 695-703, 2024 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-38808087

RESUMO

BACKGROUND: Cognitive reserve (CR) and the catechol-O-methyltransferase (COMT) Val/Met polymorphism are reportedly linked to negative symptoms in schizophrenia. However, the regulatory effect of the COMT genotype on the relationship between CR and negative symptoms is still unexamined. AIM: To investigate whether the relationship between CR and negative symptoms could be regulated by the COMT Val/Met polymorphism. METHODS: In a cross-sectional study, 54 clinically stable patients with schizophrenia underwent assessments for the COMT genotype, CR, and negative symptoms. CR was estimated using scores in the information and similarities subtests of a short form of the Chinese version of the Wechsler Adult Intelligence Scale. RESULTS: COMT Met-carriers exhibited fewer negative symptoms than Val homozygotes. In the total sample, significant negative correlations were found between negative symptoms and information, similarities. Associations between information, similarities and negative symptoms were observed in Val homozygotes only, with information and similarities showing interaction effects with the COMT genotype in relation to negative symptoms (information, ß = -0.282, 95%CI: -0.552 to -0.011, P = 0.042; similarities, ß = -0.250, 95%CI: -0.495 to -0.004, P = 0.046). CONCLUSION: This study provides initial evidence that the association between negative symptoms and CR is under the regulation of the COMT genotype in schizophrenia.

17.
Adv Mater ; 36(26): e2401857, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38594018

RESUMO

Defect-engineered bimetallic oxides exhibit high potential for the electrolysis of small organic molecules. However, the ambiguity in the relationship between the defect density and electrocatalytic performance makes it challenging to control the final products of multi-step multi-electron reactions in such electrocatalytic systems. In this study, controllable kinetics reduction is used to maximize the oxygen vacancy density of a Cu─Co oxide nanosheet (CuCo2O4 NS), which is used to catalyze the glycerol electrooxidation reaction (GOR). The CuCo2O4-x NS with the highest oxygen-vacancy density (CuCo2O4-x-2) oxidizes C3 molecules to C1 molecules with selectivity of almost 100% and a Faradaic efficiency of ≈99%, showing the best oxidation performance among all the modified catalysts. Systems with multiple oxygen vacancies in close proximity to each other synergistically facilitate the cleavage of C─C bonds. Density functional theory calculations confirm the ability of closely spaced oxygen vacancies to facilitate charge transfer between the catalyst and several key glycolic-acid (GCA) intermediates of the GOR process, thereby facilitating the decomposition of C2 intermediates to C1 molecules. This study reveals qualitatively in tuning the density of oxygen vacancies for altering the reaction pathway of GOR by the synergistic effects of spatial proximity of high-density oxygen vacancies.

18.
Joint Bone Spine ; 91(4): 105728, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38580102

RESUMO

OBJECTIVE: Systemic Lupus Erythematosus (SLE) is an autoimmune disease that occurs at higher rates in young women. Evidence suggests that SLE may be associated with ovarian dysfunction. Therefore, it is crucial to investigate the possible effects of SLE on ovarian reserve function. METHODS: PubMed, Embase, Web of Science, Scopus, Cochrane Library, and ClinicalTrials.gov databases were searched from inception to July 2023 to identify studies that compared ovarian reserve in patients with SLE to that of healthy individuals. The study examined anti-müllerian hormone (AMH), antral follicle count (AFC), and follicle-stimulating hormone (FSH) as outcomes. RESULTS: Thirteen studies (n=1017) were eligible for meta-analysis. Females with SLE had significantly lower levels of AMH (weighted mean difference [WMD]: -1.07, 95% confidence interval [CI]: -1.37 to -0.76, P<0.001) and AFC (WMD: -3.46, 95% CI: -4.57 to -2.34, P<0.001). There was no significant difference in FSH levels. Subgroup analyses by age of onset revealed that SLE patients with adult-onset had significantly lower AMH levels (WMD: -1.44, 95% CI: -1.71 to -1.18, P<0.001), lower AFCs (WMD: -3.11, 95% CI: -3.60 to -2.61, P<0.001) and higher FSH levels (WMD: 0.60, 95% CI: 0.15 to 1.05, P<0.01). However, SLE patients with juvenile-onset did not exhibit significant differences in their AMH and FSH levels, except for AFCs (WMD: -7.27, 95% CI: -12.39 to -2.14, P<0.01). CONCLUSION: The impact of SLE on ovarian reserve is significant, and the effect may be particularly severe in cases of adult-onset SLE.


Assuntos
Hormônio Antimülleriano , Lúpus Eritematoso Sistêmico , Reserva Ovariana , Humanos , Lúpus Eritematoso Sistêmico/fisiopatologia , Lúpus Eritematoso Sistêmico/sangue , Reserva Ovariana/fisiologia , Feminino , Hormônio Antimülleriano/sangue , Hormônio Foliculoestimulante/sangue , Adulto
19.
Small ; : e2402397, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634268

RESUMO

Optimizing the local electronic structure of electrocatalysts can effectively lower the energy barrier of electrochemical reactions, thus enhancing the electrocatalytic activity. However, the intrinsic contribution of the electronic effect is still experimentally unclear. In this work, the electron injection-incomplete discharge approach to achieve the electron accumulation (EA) degree on the nickel-iron layered double hydroxide (NiFe LDH) is proposed, to reveal the intrinsic contribution of EA toward oxygen evolution reaction (OER). Such NiFe LDH with EA effect results in only 262 mV overpotential to reach 50 mA cm-2, which is 51 mV-lower compared with pristine NiFe LDH (313 mV), and reduced Tafel slope of 54.8 mV dec-1 than NiFe LDH (107.5 mV dec-1). Spectroscopy characterizations combined with theoretical calculations confirm that the EA near concomitant Vo can induce a narrower energy gap and lower thermodynamic barrier to enhance OER performance. This study clarifies the mechanism of the EA effect on OER activity, providing a direct electronic structure modulation guideline for effective electrocatalyst design.

20.
J Environ Sci (China) ; 143: 176-188, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38644015

RESUMO

One-stage partial nitrification coupled with anammox (PN/A) technology effectively reduces the energy consumption of a biological nitrogen removal system. Inhibiting nitrite-oxidizing bacteria (NOB) is essential for this technology to maintain efficient nitrogen removal performance. Initial ammonium concentration (IAC) affects the degree of inhibited NOB. In this study, the effect of the IAC on a PN/A biofilm was investigated in a moving bed biofilm reactor. The results showed that nitrogen removal efficiency decreased from 82.49% ± 1.90% to 64.57% ± 3.96% after the IAC was reduced from 60 to 20 mg N/L, while the nitrate production ratio increased from 13.87% ± 0.90% to 26.50% ± 3.76%. NOB activity increased to 1,133.86 mg N/m2/day after the IAC decreased, approximately 4-fold, indicating that the IAC plays an important inhibitory role in NOB. The rate-limiting step in the mature biofilm of the PN/A system is the nitritation process and is not shifted by the IAC. The analysis of the microbial community structure in the biofilm indicates that the IAC was the dominant factor in changes in community structure. Ca. Brocadia and Ca. Jettenia were the main anammox bacteria, and Nitrosomonas and Nitrospira were the main AOB and NOB, respectively. IAC did not affect the difference in growth between Ca. Brocadia and Ca. Jettenia. Thus, modulating the IAC promoted the PN/A process with efficient nitrogen removal performance at medium to low ammonium concentrations.


Assuntos
Compostos de Amônio , Biofilmes , Reatores Biológicos , Nitrificação , Nitrogênio , Compostos de Amônio/metabolismo , Reatores Biológicos/microbiologia , Eliminação de Resíduos Líquidos/métodos , Bactérias/metabolismo , Microbiota
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